Ecomorphological characterization of murines and non-arvicoline cricetids (Rodentia from south-western Europe since the latest Middle Miocene to the Mio-Pliocene boundary (MN 7/8–MN13

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Ana R. Gomez Cano

2017-09-01

Full Text Available Rodents are the most speciose group of mammals and display a great ecological diversity. Despite the greater amount of ecomorphological information compiled for extant rodent species, studies usually lack of morphological data on dentition, which has led to difficulty in directly utilizing existing ecomorphological data of extant rodents for paleoecological reconstruction because teeth are the most common or often the only micromammal fossils. Here, we infer the environmental ranges of extinct rodent genera by extracting habitat information from extant relatives and linking it to extinct taxa based on the phenogram of the cluster analysis, in which variables are derived from the principal component analysis on outline shape of the upper first molars. This phenotypic “bracketing” approach is particularly useful in the study of the fossil record of small mammals, which is mostly represented by isolated teeth. As a case study, we utilize extinct genera of murines and non-arvicoline cricetids, ranging from the Iberoccitanian latest middle Miocene to the Mio-Pliocene boundary, and compare our results thoroughly with previous paleoecological reconstructions inferred by different methods. The resultant phenogram shows a predominance of ubiquitous genera among the Miocene taxa, and the presence of a few forest specialists in the two rodent groups (Murinae and Cricetidae, along with the absence of open environment specialists in either group of rodents. This appears to be related to the absence of enduring grassland biomes in the Iberian Peninsula during the late Miocene. High consistency between our result and previous studies suggests that this phenotypic “bracketing” approach is a very useful tool.

Ecomorphological characterization of murines and non-arvicoline cricetids (Rodentia) from south-western Europe since the latest Middle Miocene to the Mio-Pliocene boundary (MN 7/8–MN13)

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Kimura, Yuri; Blanco, Fernando; Menéndez, Iris; Álvarez-Sierra, María A.; Hernández Fernández, Manuel

2017-01-01

Rodents are the most speciose group of mammals and display a great ecological diversity. Despite the greater amount of ecomorphological information compiled for extant rodent species, studies usually lack of morphological data on dentition, which has led to difficulty in directly utilizing existing ecomorphological data of extant rodents for paleoecological reconstruction because teeth are the most common or often the only micromammal fossils. Here, we infer the environmental ranges of extinct rodent genera by extracting habitat information from extant relatives and linking it to extinct taxa based on the phenogram of the cluster analysis, in which variables are derived from the principal component analysis on outline shape of the upper first molars. This phenotypic “bracketing” approach is particularly useful in the study of the fossil record of small mammals, which is mostly represented by isolated teeth. As a case study, we utilize extinct genera of murines and non-arvicoline cricetids, ranging from the Iberoccitanian latest middle Miocene to the Mio-Pliocene boundary, and compare our results thoroughly with previous paleoecological reconstructions inferred by different methods. The resultant phenogram shows a predominance of ubiquitous genera among the Miocene taxa, and the presence of a few forest specialists in the two rodent groups (Murinae and Cricetidae), along with the absence of open environment specialists in either group of rodents. This appears to be related to the absence of enduring grassland biomes in the Iberian Peninsula during the late Miocene. High consistency between our result and previous studies suggests that this phenotypic “bracketing” approach is a very useful tool. PMID:28966888

The Quequén Salado river basin: Geology and biochronostratigraphy of the Mio-Pliocene boundary in the southern Pampean plain, Argentina

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Beilinson, E.; Gasparini, G. M.; Tomassini, R. L.; Zárate, M. A.; Deschamps, C. M.; Barendregt, R. W.; Rabassa, J.

2017-07-01

The Quequén Salado river basin has been the focus of several contributions since the first decades of the XX century, namely dealing with the general geological features of the deposits and with the vertebrate remains. In this paper, the Neogene geological history documented by the Quequén Salado river exposures is reconstructed by means of stratigraphic, sedimentological and paleomagnetic studies along with the paleontological analysis of vertebrate remains. The study area is a crucial setting not only to better understand the evolution of the southern Pampas basin during the late Miocene-early Pliocene interval, but also to test the validity of the biochronologic and biostratigraphic schemes, especially the "Irenense". A geological model for the Quequén Salado river valley is proposed: a case of downcutting and headward erosion that contributes with a coherent interpretation to explain the spatial distribution of facies and fossil taxa: the younger in the distal sector of the Quequén Salado middle basin and the older in the lower basin. The sedimentary record is believed to represent the distal reaches of a distributary fluvial system that drained from the Ventania ranges. The stratigraphic section of Paso del Indio Rico results a key stratigraphic site to fully understand the stratigraphic nature of the boundary between the Miocene and the Pliocene (the Huayquerian and Montehermosan stages/ages). In this sense, two stratigraphically superposed range zones have been recognized in the area: Xenodontomys ellipticus Range Zone (latest Miocene-early Pliocene; late Huayquerian), and Eumysops laeviplicatus Range Zone (early Pliocene; Montehermosan). Taking into account the available geological and paleontological evidences, the "Irenense" would not represent a valid biostratigraphic unit, since, according to the geological model here proposed, it would be represented by elements of the Xenodontomys ellipticus Range Zone in the lower QS basin and by elements of the

Enamel hypoplasia in the middle pleistocene hominids from Atapuerca (Spain).

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Bermúdez de Castro, J M; Pérez, P J

1995-03-01

The prevalence and chronology of enamel hypoplasias were studied in a hominid dental sample from the Sima de los Huesos (SH) Middle Pleistocene site at the Sierra de Atapuerca (Burgos, northern Spain). A total of 89 permanent maxillary teeth, 143 permanent mandibular teeth, and one deciduous lower canine, belonging to a minimum of 29 individuals, were examined. Excluding the antimeres (16 maxillary and 37 mandibular cases) from the sample, the prevalence of hypoplasias in the permanent dentition is 12.8% (23/179), whereas the deciduous tooth also showed an enamel defect. No statistically significant differences were found between both arcades and between the anterior and postcanine teeth for the prevalence of hypoplasias. In both the maxilla and the mandible the highest frequency of enamel hypoplasias was recorded in the canines. Only one tooth (a permanent upper canine) showed two different enamel defects, and most of the hypoplasias were expressed as faint linear horizontal defects. Taking into account the limitations that the incompleteness of virtually all permanent dentitions imposes, we have estimated that the frequency by individual in the SH hominid sample was not greater than 40%. Most of the hypoplasias occurred between birth and 7 years (N = 18, X = 3.5, SD = 1.3). Both the prevalence and severity of the hypoplasias of the SH hominid sample are significantly less than those of a large Neandertal sample. Furthermore, prehistoric hunter-gatherers and historic agricultural and industrial populations exhibit a prevalence of hypoplasias generally higher than that of the SH hominids. Implications for the survival strategies and life quality of the SH hominids are also discussed.

Pliocene climate

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Dowsett, Harry J.; Caballero-Gill, R. P.

2010-01-01

The Pliocene Epoch, 5.3 Ma to 1.8 Ma, was a time when paleoclimate conditions ranged from very warm, equable climates (on a global scale), rhythmically varying every 40,000 years, to high-amplitude glacial-interglacial cycles that led to the “Ice Ages” of the Pleistocene. Evidence for paleoclimate conditions comes from fossils, geochemical data, and the integration of these data with sophisticated numerical models. The Pliocene exhibited a range in atmospheric CO2 concentrations with highs estimated to be at most ~425 ppm in the early Pliocene followed by overall decrease toward preindustrial levels by the close of the Pliocene Epoch (Pagani et al. 2010). Sea levels were estimated to be 25m higher than present day and the size and position of ice sheets in Greenland and Antarctica were decidedly different from today. On the other hand, by the mid-Pliocene, the majority of fauna and flora as well as continental configurations were basically the same as today. Man’s ability to adapt to or mitigate the effects of future climate require a deep understanding of the rates and magnitude of future climate change on an ever finer scale. Since conditions projected for the end of this century are not in the human experience, we depend upon a combination of numerical climate models and comparison to analogous conditions in the geologic past. The Pliocene contains what might be the closest analog to climate conditions expected in the near future, and therefore understanding the Pliocene is not only of academic interest but essential for human adaptation.

Evidence for widespread degradation of gene control regions in hominid genomes.

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Peter D Keightley

2005-02-01

Full Text Available Although sequences containing regulatory elements located close to protein-coding genes are often only weakly conserved during evolution, comparisons of rodent genomes have implied that these sequences are subject to some selective constraints. Evolutionary conservation is particularly apparent upstream of coding sequences and in first introns, regions that are enriched for regulatory elements. By comparing the human and chimpanzee genomes, we show here that there is almost no evidence for conservation in these regions in hominids. Furthermore, we show that gene expression is diverging more rapidly in hominids than in murids per unit of neutral sequence divergence. By combining data on polymorphism levels in human noncoding DNA and the corresponding human-chimpanzee divergence, we show that the proportion of adaptive substitutions in these regions in hominids is very low. It therefore seems likely that the lack of conservation and increased rate of gene expression divergence are caused by a reduction in the effectiveness of natural selection against deleterious mutations because of the low effective population sizes of hominids. This has resulted in the accumulation of a large number of deleterious mutations in sequences containing gene control elements and hence a widespread degradation of the genome during the evolution of humans and chimpanzees.

Dating of fossil hominid: problems and perspectives

International Nuclear Information System (INIS)

Poupeau, G.; Danon, J.; Baksi, A.K.

1984-01-01

The hominid dating anterior to the Homo Erectus has been based up to now on the rocks and minerals geochronology of vulcanic origem in stratigraphic relation with the fossils. Two methods are widely used, potassium-argon and uranium fission track dating. The vulcanic material dating; lava, lephra, associated with the hominid leavings show big difficults essentially connected to several types of contamination and modification. Two available examples inside the east-african rift show the probelms linked to these dating. The current progresses in the dating methods can contribute by one hand to a better utilization of the K-Ar and fisson track methods for the vulcanic materials. By other hand, with the introduction of new dating methods (thermoluminescence and electron paramagnetic resonance) will be possible to date directly whether the fossil bone itself or the associated sedimentar material. This open new perspectives in particular for every sites which are not inter-stratified with the vulcanic material. (L.C.) [pt

Lapa vermelha IV Hominid 1: morphological affinities of the earliest known American

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Neves Walter A.

1999-01-01

Full Text Available Several studies concerning the extra-continental morphological affinities of Paleo-Indian skeletons, carried out independently in South and North America, have indicated that the Americas were first occupied by non-Mongoloids that made their way to the New World through the Bering Strait in ancient times. The first South Americans show a clear resemblance to modern South Pacific and African populations, while the first North Americans seem to be at an unresolved morphological position between modern South Pacific and Europeans. In none of these analyses the first Americans show any resemblance to either northeast Asians or modern native Americans. So far, these studies have included affirmed and putative early skeletons thought to date between 8,000 and 10,000 years B.P. In this work the extra-continental morphological affinities of a Paleo-Indian skeleton well dated between 11,000 and 11,500 years B.P. (Lapa Vermelha IV Hominid 1, or "Luzia" is investigated, using as comparative samples Howells' (1989 world-wide modern series and Habgood's (1985 Old World Late Pleistocene fossil hominids. The comparison between Lapa Vermelha IV Hominid 1 and Howells' series was based on canonical variate analysis, including 45 size-corrected craniometric variables, while the comparison with fossil hominids was based on principal component analysis, including 16 size-corrected variables. In the first case, Lapa Vermelha IV Hominid 1 exhibited an undisputed morphological affinity firstly with Africans and secondly with South Pacific populations. In the second comparison, the earliest known American skeleton had its closest similarities with early Australians, Zhoukoudian Upper Cave 103, and Taforalt 18. The results obtained clearly confirm the idea that the Americas were first colonized by a generalized Homo sapiens population which inhabited East Asia in the Late Pleistocene, before the definition of the classic Mongoloid morphology.

Working Memory: A Cognitive Limit to Non-Human Primate Recursive Thinking Prior to Hominid Evolution

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Dwight W. Read

2008-10-01

Full Text Available In this paper I explore the possibility that recursion is not part of the cognitive repertoire of non-human primates such as chimpanzees due to limited working memory capacity. Multiple lines of data, from nut cracking to the velocity and duration of cognitive development, imply that chimpanzees have a short-term memory size that limits working memory to dealing with two, or at most three, concepts at a time. If so, as a species they lack the cognitive capacity for recursive thinking to be integrated into systems of social organization and communication. If this limited working memory capacity is projected back to a common ancestor for Pan and Homo, it follows that early hominid ancestors would have had limited working memory capacity. Hence we should find evidence for expansion of working memory capacity during hominid evolution reflected in changes in the products of conceptually framed activities such as stone tool production. Data on the artifacts made by our hominid ancestors support this expansion hypothesis for hominid working memory, thereby leading to qualitative differences between Pan and Homo.

A Task No Maritime Operational Commander Wants: Maritime Interception Operations (MIO) Are Not Going Away

National Research Council Canada - National Science Library

Dawley, Sterling

2003-01-01

Maritime Interception Operations (MIO) as a mission area for USN and USCG assets does not seem to be going away anytime soon The purpose of this essay is to assess past MIO efforts and offer recommendations to assist the operational...

Dental size variation in the Atapuerca-SH Middle Pleistocene hominids.

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Bermúdez de Castro, J M; Sarmiento, S; Cunha, E; Rosas, A; Bastir, M

2001-09-01

The Middle Pleistocene Atapuerca-Sima de los Huesos (SH) site in Spain has yielded the largest sample of fossil hominids so far found from a single site and belonging to the same biological population. The SH dental sample includes a total of 452 permanent and deciduous teeth, representing a minimum of 27 individuals. We present a study of the dental size variation in these hominids, based on the analysis of the mandibular permanent dentition: lateral incisors, n=29; canines, n=27; third premolars, n=30; fourth premolars, n=34; first molars, n=38; second molars, n=38. We have obtained the buccolingual diameter and the crown area (measured on occlusal photographs) of these teeth, and used the bootstrap method to assess the amount of variation in the SH sample compared with the variation of a modern human sample from the Museu Antropologico of the Universidade of Coimbra (Portugal). The SH hominids have, in general terms, a dental size variation higher than that of the modern human sample. The analysis is especially conclusive for the canines. Furthermore, we have estimated the degree of sexual dimorphism of the SH sample by obtaining male and female dental subsamples by means of sexing the large sample of SH mandibular specimens. We obtained the index of sexual dimorphism (ISD=male mean/female mean) and the values were compared with those obtained from the sexed modern human sample from Coimbra, and with data found in the literature concerning several recent human populations. In all tooth classes the ISD of the SH hominids was higher than that of modern humans, but the differences were generally modest, except for the canines, thus suggesting that canine size sexual dimorphism in Homo heidelbergensis was probably greater than that of modern humans. Since the approach of sexing fossil specimens has some obvious limitations, these results should be assessed with caution. Additional data from SH and other European Middle Pleistocene sites would be necessary to test

Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela)

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2015-01-01

The Urumaco stratigraphic sequence, western Venezuela, preserves a variety of paleoenvironments that include terrestrial, riverine, lacustrine and marine facies. A wide range of fossil vertebrates associated with these facies supports the hypothesis of an estuary in that geographic area connected with a hydrographic system that flowed from western Amazonia up to the Proto-Caribbean Sea during the Miocene. Here the elasmobranch assemblages of the middle Miocene to middle Pliocene section of the Urumaco sequence (Socorro, Urumaco and Codore formations) are described. Based on new findings, we document at least 21 taxa of the Lamniformes, Carcharhiniformes, Myliobatiformes and Rajiformes, and describe a new carcharhiniform species (†Carcharhinus caquetius sp. nov.). Moreover, the Urumaco Formation has a high number of well-preserved fossil Pristis rostra, for which we provide a detailed taxonomic revision, and referral in the context of the global Miocene record of Pristis as well as extant species. Using the habitat preference of the living representatives, we hypothesize that the fossil chondrichthyan assemblages from the Urumaco sequence are evidence for marine shallow waters and estuarine habitats. PMID:26488163

Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela.

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Jorge D Carrillo-Briceño

Full Text Available The Urumaco stratigraphic sequence, western Venezuela, preserves a variety of paleoenvironments that include terrestrial, riverine, lacustrine and marine facies. A wide range of fossil vertebrates associated with these facies supports the hypothesis of an estuary in that geographic area connected with a hydrographic system that flowed from western Amazonia up to the Proto-Caribbean Sea during the Miocene. Here the elasmobranch assemblages of the middle Miocene to middle Pliocene section of the Urumaco sequence (Socorro, Urumaco and Codore formations are described. Based on new findings, we document at least 21 taxa of the Lamniformes, Carcharhiniformes, Myliobatiformes and Rajiformes, and describe a new carcharhiniform species (†Carcharhinus caquetius sp. nov.. Moreover, the Urumaco Formation has a high number of well-preserved fossil Pristis rostra, for which we provide a detailed taxonomic revision, and referral in the context of the global Miocene record of Pristis as well as extant species. Using the habitat preference of the living representatives, we hypothesize that the fossil chondrichthyan assemblages from the Urumaco sequence are evidence for marine shallow waters and estuarine habitats.

Sawfishes and Other Elasmobranch Assemblages from the Mio-Pliocene of the South Caribbean (Urumaco Sequence, Northwestern Venezuela).

Science.gov (United States)

Carrillo-Briceño, Jorge D; Maxwell, Erin; Aguilera, Orangel A; Sánchez, Rodolfo; Sánchez-Villagra, Marcelo R

2015-01-01

The Urumaco stratigraphic sequence, western Venezuela, preserves a variety of paleoenvironments that include terrestrial, riverine, lacustrine and marine facies. A wide range of fossil vertebrates associated with these facies supports the hypothesis of an estuary in that geographic area connected with a hydrographic system that flowed from western Amazonia up to the Proto-Caribbean Sea during the Miocene. Here the elasmobranch assemblages of the middle Miocene to middle Pliocene section of the Urumaco sequence (Socorro, Urumaco and Codore formations) are described. Based on new findings, we document at least 21 taxa of the Lamniformes, Carcharhiniformes, Myliobatiformes and Rajiformes, and describe a new carcharhiniform species (†Carcharhinus caquetius sp. nov.). Moreover, the Urumaco Formation has a high number of well-preserved fossil Pristis rostra, for which we provide a detailed taxonomic revision, and referral in the context of the global Miocene record of Pristis as well as extant species. Using the habitat preference of the living representatives, we hypothesize that the fossil chondrichthyan assemblages from the Urumaco sequence are evidence for marine shallow waters and estuarine habitats.

Reexamination of the immature hominid maxilla from Tangier, Morocco.

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Minugh-Purvis, N

1993-12-01

Reexamination of the immature Upper Pleistocene hominid maxilla from Mugharet el-'Aliya (Tangier), Morocco is undertaken in light of new evidence on the growth and development of Upper Pleistocene hominids. Metric and qualitative comparisons were made with 17 immature Upper Pleistocene maxillae, and with a recent Homo sapiens sapiens sample. No unambiguous criteria for aligning the maxilla with Neandertals were found, although one character, the degree of maxillary flexion on the zygoma, strongly suggests that this child could be a representative of H.s. sapiens. The probable lack of a canine fossa in Mugharet el-'Aliya 1, the primary criterion used previously to align it with Neandertals, cannot be accurately extrapolated to its adult form from this juvenile. The present evidence suggests that it is inappropriate to refer to this fossil as "Neandertal-like" or as a North African "neandertaloid." Thus, the Tangier maxilla should not be cited as evidence for the presence of Neandertal facial features in North Africa during the Upper Pleistocene.

Age of the earliest known hominids in Java, Indonesia.

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Swisher, C C; Curtis, G H; Jacob, T; Getty, A G; Suprijo, A; Widiasmoro

1994-02-25

40Ar/39Ar laser-incremental heating of hornblende separated from pumice recovered at two hominid sites in Java, Indonesia, has yielded well-defined plateaus with weighted mean ages of 1.81 +/- 0.04 and 1.66 +/- 0.04 million years ago (Ma). The hominid fossils, a juvenile calvaria of Pithecanthropus and a partial face and cranial fragments of Meganthropus, commonly considered part of the Asian Homo erectus hypodigm, are at least 0.6 million years older than fossils referred to as Homo erectus (OH-9) from Olduvai Gorge, Tanzania, and comparable in age with the oldest Koobi Fora Homo cf. erectus (Homo ergaster) in Kenya. These ages lend further credence to the view that Homo erectus may have evolved outside of Africa. If the ancestor of Homo erectus ventured out of Africa before 1.8 Ma, the dispersal would have predated the advent of the Acheulean culture at 1.4 Ma, possibly explaining the absence of these characteristic stone cleavers and hand axes in East Asia.

Large-Scale Features of Pliocene Climate: Results from the Pliocene Model Intercomparison Project

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Haywood, A. M.; Hill, D.J.; Dolan, A. M.; Otto-Bliesner, B. L.; Bragg, F.; Chan, W.-L.; Chandler, M. A.; Contoux, C.; Dowsett, H. J.; Jost, A.;

Earliest Pleistocene hominid cranial remains from Dmanisi, Republic of Georgia: taxonomy, geological setting, and age.

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Gabunia, L; Vekua, A; Lordkipanidze, D; Swisher, C C; Ferring, R; Justus, A; Nioradze, M; Tvalchrelidze, M; Antón, S C; Bosinski, G; Jöris, O; Lumley, M A; Majsuradze, G; Mouskhelishvili, A

2000-05-12

Archaeological excavations at the site of Dmanisi in the Republic of Georgia have uncovered two partial early Pleistocene hominid crania. The new fossils consist of a relatively complete cranium and a second relatively complete calvaria from the same site and stratigraphic unit that yielded a hominid mandible in 1991. In contrast with the uncertain taxonomic affinity of the mandible, the new fossils are comparable in size and morphology with Homo ergaster from Koobi Fora, Kenya. Paleontological, archaeological, geochronological, and paleomagnetic data from Dmanisi all indicate an earliest Pleistocene age of about 1.7 million years ago, supporting correlation of the new specimens with the Koobi Fora fossils. The Dmanisi fossils, in contrast with Pleistocene hominids from Western Europe and Eastern Asia, show clear African affinity and may represent the species that first migrated out of Africa.

Posterior dental size reduction in hominids: the Atapuerca evidence.

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Bermúdez de Castro, J M; Nicolas, M E

1995-04-01

In order to reassess previous hypotheses concerning dental size reduction of the posterior teeth during Pleistocene human evolution, current fossil dental evidence is examined. This evidence includes the large sample of hominid teeth found in recent excavations (1984-1993) in the Sima de los Huesos Middle Pleistocene cave site of the Sierra de Atapuerca (Burgos, Spain). The lower fourth premolars and molars of the Atapuerca hominids, probably older than 300 Kyr, have dimensions similar to those of modern humans. Further, these hominids share the derived state of other features of the posterior teeth with modern humans, such as a similar relative molar size and frequent absence of the hypoconulid, thus suggesting a possible case of parallelism. We believe that dietary changes allowed size reduction of the posterior teeth during the Middle Pleistocene, and the present evidence suggests that the selective pressures that operated on the size variability of these teeth were less restrictive than what is assumed by previous models of dental reduction. Thus, the causal relationship between tooth size decrease and changes in food-preparation techniques during the Pleistocene should be reconsidered. Moreover, the present evidence indicates that the differential reduction of the molars cannot be explained in terms of restriction of available growth space. The molar crown area measurements of a modern human sample were also investigated. The results of this study, as well as previous similar analyses, suggest that a decrease of the rate of cell proliferation, which affected the later-forming crown regions to a greater extent, may be the biological process responsible for the general and differential dental size reduction that occurred during human evolution.

Africa's wild C4 plant foods and possible early hominid diets.

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Peters, Charles R; Vogel, John C

2005-03-01

A small minority of Africa's wild plant foods are C4. These are primarily the seeds of some of the C4 grasses, the rootstocks and stem/leaf bases of some of the C4 sedges (especially papyrus), and the leaves of some of the C4 herbaceous dicots (forbs). These wild food plants are commonly found in disturbed ground and wetlands (particularly the grasses and sedges). Multiple lines of evidence indicate that C4 grasses were present in Africa by at least the late Miocene. It is a reasonable hypothesis that the prehistory of the C4 sedges parallels that of the C4 grasses, but the C4 forbs may not have become common until the late Pleistocene. CAM plants may have a more ancient history, but offer few opportunities for an additional C4-like dietary signal. The environmental reconstructions available for the early South African hominid sites do not indicate the presence of large wetlands, and therefore probably the absence of a strong potential for a C4 plant food diet. However, carbon isotope analyses of tooth enamel from three species of early South African hominids have shown that there was a significant but not dominant contribution of C4 biomass in their diets. Since it appears unlikely that this C4 component could have come predominantly from C4 plant foods, a broad range of potential animal contributors is briefly considered, namely invertebrates, reptiles, birds, and small mammals. It is concluded that the similar average C4 dietary intake seen in the three South African hominid species could have been acquired by differing contributions from the various sources, without the need to assume scavenging or hunting of medium to large grazing ungulates. Effectively similar dominantly dryland paleo-environments may also be part of the explanation. Theoretically, elsewhere in southern and eastern Africa, large wetlands would have offered early hominids greater opportunities for a C4 plant diet.

Paléocontraintes et déformations syn- et post-collision Afrique Europe identifiées dans la couverture mésozoïque et cénozoïque du Haut Atlas occidental (Maroc)Syn- and post-collision Africa Europe palaeostresses and deformations identified in the West High-Atlas Mesozoic and Cenozoic cover (Morocco)

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Amrhar, Mostafa

Palaeostresses and deformation axis reconstruction related to the intracontinental High-Atlas uplift evidences two shortening phases from Upper Cretaceous to Quaternary. The first compression is oriented N20-30°E and is Maastrichtian to Oligocene age; the second one, oriented N120-160°E, is syn-Mio-Pliocene. Tectonic inversion of the lateral to compressive Jurassic regime is contemporaneous with the beginning of Africa and Europe collision. Rotation of the Mio-Pliocene shortening orientation could be linked to the change of the convergence direction between the Africa and Europe plates. To cite this article: M. Amrhar, C. R. Geoscience 334 (2002) 279-285.

Phenylalanine ammonia lyase catalyzed synthesis of amino acids by an MIO-cofactor independent pathway.

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Lovelock, Sarah L; Lloyd, Richard C; Turner, Nicholas J

2014-04-25

Phenylalanine ammonia lyases (PALs) belong to a family of 4-methylideneimidazole-5-one (MIO) cofactor dependent enzymes which are responsible for the conversion of L-phenylalanine into trans-cinnamic acid in eukaryotic and prokaryotic organisms. Under conditions of high ammonia concentration, this deamination reaction is reversible and hence there is considerable interest in the development of PALs as biocatalysts for the enantioselective synthesis of non-natural amino acids. Herein the discovery of a previously unobserved competing MIO-independent reaction pathway, which proceeds in a non-stereoselective manner and results in the generation of both L- and D-phenylalanine derivatives, is described. The mechanism of the MIO-independent pathway is explored through isotopic-labeling studies and mutagenesis of key active-site residues. The results obtained are consistent with amino acid deamination occurring by a stepwise E1 cB elimination mechanism. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pattern of dental development in Hominid XVIII from the Middle Pleistocene Atapuerca-Sima de los Huesos site (Spain).

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Bermudez De Castro, J M; Rosas, A

2001-04-01

. We describe the pattern of dental development of Hominid XVIII from the Middle Pleistocene Sima de los Huesos (SH) site of the Sierra de Atapuerca (Burgos, Spain). As expected, this pattern is similar to that of modern humans. A delay of development of the lower and upper canines was observed. In contrast, the relative advanced development of the lower second molars and, especially, the upper and lower third molars is noteworthy. This latter feature seems to be common in Pleistocene hominids, and suggests that the pattern of dental development evolved in the genus Homo during the Pleistocene. In European Middle Pleistocene hominids, this pattern probably was facilitated by the extra space available in the mandible and maxilla for developing teeth. Copyright 2001 Wiley-Liss, Inc.

Cerebral cortices of East african early hominids.

Science.gov (United States)

Falk, D

1983-09-09

An endocast of the frontal lobe of a reconstructed skull, which is approximately 2 million years old, from the Koobi Fora region of Kenya appears to represent the oldest human-like cortical sulcal pattern in the fossil record, while the endocast from another skull from the same region produces an endocast that appears apelike in its frontal lobe and similar to endocasts from earlier South African australopithecines. New analysis of paleoanatomical evidence thus indicates that at least two taxa of early hominids coexisted in East Africa.

Disturbed mitochondrial function restricts glutamate uptake in the human Müller glia cell line, MIO-M1

DEFF Research Database (Denmark)

Vohra, Rupali; Gurubaran, Iswariyaraja Sridevi; Henriksen, Ulrik

2017-01-01

Using the human Müller cell line, MIO-M1, the aim was to study the impact of mitochondrial inhibition in Müller glia through antimycin A treatment. MIO-M1 cell survival, levels of released lactate, mitochondrial function, and glutamate uptake were studied in response to mitochondrial inhibition...... and glucose restriction. Lactate release decreased in response to glucose restriction. Combined glucose restriction and blocked mitochondrial activity decreased survival and caused collapse of the respiratory chain measured by oxygen consumption rate and extracellular acidification rate. Mitochondrial...... inhibition caused impaired glutamate uptake and decreased mRNA expression of the glutamate transporter, EAAT1. Over all, we show important roles of mitochondrial activity in MIO-M1 cell function and survival....

Pliocene geomagnetic polarity epochs

Science.gov (United States)

Dalrymple, G.B.; Cox, A.; Doell, Richard R.; Gromme, C.S.

1967-01-01

A paleomagnetic and K-Ar dating study of 44 upper Miocene and Pliocene volcanic units from the western United States suggests that the frequency of reversals of the earth's magnetic field during Pliocene time may have been comparable with that of the last 3.6 m.y. Although the data are too limited to permit the formal naming of any new polarity epochs or events, four polarity transitions have been identified: the W10 R/N boundary at 3.7 ?? 0.1 m.y., the A12 N/R boundary at 4.9 ?? 0.1 m.y., the W32 N/R boundary at 9.0 ?? 0.2m.y., and the W36 R/N boundary at 10.8 ?? 0.3 - 1.0 m.y. The loss of absolute resolution of K-Ar dating in older rocks indicates that the use of well defined stratigraphic successions to identify and date polarity transitions will be important in the study of Pliocene and older reversals. ?? 1967.

Dating by fission tracks in archaeology. 3. Tephrochronology and Hominid dating

International Nuclear Information System (INIS)

Poupeau, G.; Zuleta, E.

1984-01-01

Tephras (or volcanic ashes) are excellent stratigraphic tracers. Its utilization in this domain, or tephrochronology, is shortly presented. The main archaeological utilization of the tephrochronology is related with the dating of fossil hominids, there where exist the volcano-fossil sedimentar series, at Ceylon or at East-African Rift. (L.C.) [pt

The face of Olduvai Hominid 12.

Science.gov (United States)

Antón, Susan C

2004-03-01

Facial remains of Homo erectus are rare and their scarcity hinders our understanding of the variability and relationships in this taxon. Previously undescribed fragments of the peri-orbital region and unidentified matches between fragments of Olduvai Hominid 12 (OH 12) enhance comparison of the African H. erectus hypodigm. The newly reconstructed upper face and maxilla of OH 12 is most similar in size and shape to that of KNM-ER 3733, despite being as much as one million years younger than the Koobi Fora hominin. However, the posterior vault and mastoid region of OH 12 are most similar to OH 9. This combination of morphology suggests that the relationship between the Olduvai and Koobi Fora portions of the H. erectus hypodigm requires reconsideration.

Buchi neri nel mio bagno di schiuma l’enigma di Einstein

CERN Document Server

Vishveshwara, C V

2008-01-01

"Le bolle stavano turbinando tutto intorno a me e massaggiavano il mio corpo ... Mentre me la godevo in questo fantastico bagno di bolle, i miei occhi si fecero pesanti e mi lasciaii trasportare in un dormiveglia sublimamente estatico". Così inizia l’incontro di Alfie con una vasca da bagno eccezionale e rivelatrice, acquistata da un vicino misterioso di nome Al. L’Enigma di Einstein, ovvero buchi neri nel mio bagno di schiuma, racconta la storia della teoria della gravitazione, dai suoi primordi fino agli ultimi sviluppi in astrofisica, focalizzandosi sulla teoria della relatività generale di Albert Einstein e sulla fisica dei buchi neri. Tramite conversazioni avvincenti e diagrammi scarabocchiati su tovaglioli di carta, si susseguono a ruota i rudimenti della relatività, dello spazio-tempo e di molti aspetti della fisica moderna. In scenette narrate con abilità pedagogica e notevole talento letterario, il lettore s’imbatterà nelle lezioni informali che un astrofisico cosmopolita tiene al suo amic...

Revisions of K/Ar ages for the Hadar hominid site, Ethiopia

Energy Technology Data Exchange (ETDEWEB)

Walter, R.C.; Aronson, J.L. (Case Western Reserve Univ., Cleveland, OH (USA). Dept. of Geology)

1982-03-11

Conventional K/Ar age measurements are reported for two volcanic units from the hominid-bearing Hadar Formation. These ages represent revision of previously published ages for the BKT-2 tephra and the Kadada Moumou basalt. BKT-2 is revised from 2.65 to 2.9 Myr BP and the Kadada Moumou basalt is revised from 3.0 to 3.6 Myr BP.

O Manicômio Judiciário: saúde ou justiça? The Judiciary Mental Hospital: a question of health or of law?

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Evelin Naked de Castro Sá

1985-10-01

Full Text Available O Manicômio Judiciário, por ser um hospital-presídio, pode estar subordinado tanto à Secretaria da Saúde como à Justiça. Como elementos de análise dessa decisão, são apresentadas comparações estruturais e de recursos humanos entre o Manicômio Judiciário e a Penitenciária de Araraquara, entre a situação de recursos humanos do Manicômio em 1981 e 1984 e entre os salários de algumas funções de servidores ligados àqueles tipos de instituições. As conclusões apontam a Secretaria da Justiça como a mais adequada para subordinar o Manicômio Judiciário, desde que tomadas algumas medidas de modernização organizacional. É sugerido um quadro de pessoal estruturado percentualmente por subgrupos de funções. As propostas relativas ao pessoal necessitam ser tratadas em leis complementares que garantam, por sua hierarquia, o atendimento das condições excepcionais de trabalho do Manicômio Judiciário.As the Manicômio Judiciário (a Judiciary Mental Health Hospital is a hospital-prison it could be subordinated either to the State Health Department or to the Department of Justice. In order to reach a sound decision regarding this issue, structural and human resource comparisons as between the Manicômio Judiciário on one side and the Araraquara Prison on the other are provided. Comparisons between the status of the human resources of the Manicômio Judiciário in 1981 and 1984 and between the wages earned by workers exercising similar functions and belonging to similar institutions are also presented. The conclusion points to the Department of Justice as the most adequate institution to which the Manicômio Judiciário should be subordinated, provided some up-to-date managerial measures are taken. A personnel chart is suggested, showing percentages of people organized according to subgroups of functions. The proposals regarding personnel must be dealt with by, supplementary laws which guarantee, adequate provision for the

A roe deer from the Pliocene of Hidalgo, central Mexico

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Eduardo Jiménez-Hidalgo

2015-12-01

Full Text Available Mexican Pliocene cervids are very poorly known. We report on new fossil material of the roe deer Capreolus constantini recovered from the Pliocene Atotonilco El Grande Formation of Santa María Amajac, Hidalgo (central Mexico. The specimens were collected from a series of layers of friable to moderately indurated polymictic conglomerate supported by a sandstone-tuffaceous-calcareous matrix. This species was formerly known only from the late Pliocene of Udunga, Russia, thus implying a dispersal event to North America around 4.0 Ma. This cervid is one of the very small number of mammals recorded from the poorly sampled Pliocene temperate deposits of Mexico.

Will dragonblood survive the next period of climate change? Current and future potential distribution of Dracaena cinnabari (Socotra, Yemen)

NARCIS (Netherlands)

Attorre, F.; Francesconi, F.; Taleb, N.; Scholte, P.; Saed, A.; Alfo, M.; Bruno, F.

2007-01-01

The potential impact of climate change on Dracaena cinnabari, a spectacular relict of the Mio-Pliocene Laurasian subtropical forest in Socotra (Yemen), was analysed. Current distribution, abundance and vertical structure of D. cinnabari populations were assessed with 74 plots in nine remnant areas.

Cuestiones de ecdótica en torno al Mio Cid

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Leonardo Funes

2007-11-01

Full Text Available This article proposes a revision of certain issues related to the critical edition of the Poema de Mio Cid, such as the discussion about how to consider or use the results of previous editors or the contemporary debate launched by partisans of hiper-conservative editions. It also discusses specific points of the editorial task, such as guides and criteria for enmendatory practice, and ilustrative loci selected from my own experience in editing the poem.

Pliocene Paleoenvironments of the Awash Valley, Ethiopia: The Isotope Record of Tooth Enamel and its Relevance to the Pliocene Paleoclimate of Northeastern Africa

Science.gov (United States)

Bedaso, Z. K.; Wynn, J. G.; Alemseged, Z.

2010-12-01

Understanding patterns of Pliocene environmental and climate change using data from terrestrial deposits helps to identify factors which govern the climate, and to unravel potential links between regional and global climate conditions. We use the stable carbon (C) and oxygen (O) isotopic composition of bioapatite from fossil tooth enamel to reconstruct Pliocene environmental and climatic changes at Dikika and Galili, in the Awash valley of Ethiopia. Our application of C and O isotopes aims principally at reconstructing shifts in floral composition, such as the relative abundance of C4 grasses, and its implications for climate indicators including temperature, aridity, and seasonality, and the role of climate in early hominin evolution. C isotopic composition of tooth enamel is based on differences in C isotope discrimination between plants that use the two major photosynthetic pathways (C3 and C4), the abundance of which are driven by climate variables, and the transfer of this “signature” between plant foods in the diet of mammals and mammalian tooth enamel δ13C values (ɛdiet-enamel). A change in δ13Cenamel values between 5.26 and 3.24 Ma provides insight to early hominin environments, which varied from open woodland and grassland to closed woodland in the early to mid Pliocene at Galili and wooded grassland both in Galili and Dikika in the late Pliocene. Similarly, the O isotopic composition of tooth enamel is a function of the isotopic composition of body water, which in turn is a function of meteoric and physiological processes, and therefore may also reflect local climatic conditions if the physiological factors can be constrained. Using an O isotope enrichment factor between δ18Oenamel carbonate and δ18Obody water (ɛEC-BW =26.3) and between evaporation sensitive and insensitive taxa (ɛES-EI = 2.1-4.2), we estimate the Pliocene δ18O value of meteoric water, which ranges from -2.4 to -5.2 ‰ in early and mid Pliocene respectively. An observed

Comparative morphometric analysis of the proximal femur of African hominids and felids

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Andrew Gallagher

2015-09-01

Full Text Available Size and shape of the mammalian proximal femur and taxon-specific distinctions in the relative proportions of the proximal articulation, the femoral neck and the proximal femoral diaphysis, are critical determinants in its adaptation to differential biomechanical stresses and observed locomotor habitus in different taxa. The morphometrics of the proximal femur are considered equally critical in the assessment of locomotor habitus of extinct fossil mammals, particularly extinct Miocene anthropoids and Plio-Pleistocene hominins. Analyses of size and shape of k=10 dimensions of the proximal femur were undertaken for a large sample series of two extant mammal families the Felidae and Hominidae using conventional multivariate statistical procedures, commonly used size-correction methods, and post-hoc tests of significance. While significant differences in form do exist, there are equally striking convergences in the functional morphology of extant hominid and felid taxa. Multivariate and bivariate allometric analyses confirm that the proximal femur of these two mammalian families share a common underlying structure manifest in a shared first common principal component. Nevertheless, while considerable convergences in general form of the proximal femur of African hominids and large-bodied felids are apparent, there exist equally discreet distinctions which are consistent with the differential structural demands imposed by their distinct locomotor and behavioural habitus.

Ages of tuff beds at East African early hominid sites and sediments in the Gulf of Aden

Science.gov (United States)

Sarna-Wojcicki, A. M.; Meyer, C.E.; Roth, P.H.; Brown, F.H.

1985-01-01

The early hominids of East Africa were dated by determining the ages of tuff beds at the sites. Despite much research using palaeomagnetic and K/Ar-dating techniques, some of those ages are still controversial 1,2. To obtain independent age estimates for these tephra layers, we have examined cores from DSDP Sites 231 and 232 in the Gulf of Aden (Fig. 1a) which consist mainly of calcareous nannofossil ooze, but also contain rare tephra horizons3 dated by interpolation from the established nannofossil stratigraphy (Fig. 1b). Chemical analysis confirms that the identity and sequence of these horizons is the same as that at the East African sites. We conclude that the age of the Tulu Bor Tuff is <3.4 Myr and hence that the Hadar hominid specimens are also

El Nino in the Pliocene

NARCIS (Netherlands)

von der Heydt, A.S.; Dijkstra, H.A.

2011-01-01

Whether interannual variability in the Pacific Ocean was a feature of the warm Pliocene climate is debated. Variance in reconstructed eastern tropical Pacific surface temperatures provides strong support for persistent El Niño activity at this time.

Teleconnections in a warmer climate: the pliocene perspective

Energy Technology Data Exchange (ETDEWEB)

Shukla, Sonali P. [Columbia University, Deptartment of Earth and Environmental Sciences and the NASA Goddard Institute for Space Studies, New York, NY (United States); Chandler, Mark A.; Sohl, Linda E.; Jonas, Jeff; Lerner, Jean [Columbia University, Center for Climate Systems Research, New York, NY (United States); Rind, David [National Aeronautics and Space Administration, Goddard Institute for Space Studies, New York, NY (United States)

2011-11-15

Migrations toward altered sea surface temperature (SST) patterns in the Indo-Pacific region are present in the recent observational record and in future global warming projections. These SSTs are in the form of ''permanent'' El Nino-like (herein termed ''El Padre'') and Indian Ocean Dipole (IOD)-like patterns. The Early Pliocene Warm Period, which bears similarity to future warming projections, may have also exhibited these Indo-Pacific SST patterns, as suggested by regional terrestrial paleo-climatic data and general circulation model studies. The ability to corroborate this assessment with paleo-data reconstructions is an advantage of the warm Pliocene period that is not afforded by future warming scenarios. Thus, the Pliocene period provides us with a warm-climate perspective and test bed for understanding potential changes to future atmospheric interactions given these altered SST states. This study specifically assesses how atmospheric teleconnections from El Padre/IOD SST patterns are generated and propagate to create the regional climate signals of the Pliocene period, as these signals may be representative of future regional climatic changes as well. To do this, we construct a holistic diagnostic rubric that allows us to examine atmospheric teleconnections, both energetically and dynamically, as produced by a general circulation model. We incorporate KE', a diagnostic adapted from the eddy kinetic energy generation field, to assess the available energy transferred to these teleconnections. Using this methodology, we found that relative to our Modern Control experiments, weaker atmospheric teleconnections prevail under warm Pliocene conditions, although pathways of propagation still appear directed toward the southwestern United States from our tropical Pacific sector forcing. Propagation directly emanating from the Indian Ocean forcing sector appears to be largely blocked, although indirect teleconnective

Hominid mandibular corpus shape variation and its utility for recognizing species diversity within fossil Homo.

Science.gov (United States)

Lague, Michael R; Collard, Nicole J; Richmond, Brian G; Wood, Bernard A

2008-12-01

Mandibular corpora are well represented in the hominin fossil record, yet few studies have rigorously assessed the utility of mandibular corpus morphology for species recognition, particularly with respect to the linear dimensions that are most commonly available. In this study, we explored the extent to which commonly preserved mandibular corpus morphology can be used to: (i) discriminate among extant hominid taxa and (ii) support species designations among fossil specimens assigned to the genus Homo. In the first part of the study, discriminant analysis was used to test for significant differences in mandibular corpus shape at different taxonomic levels (genus, species and subspecies) among extant hominid taxa (i.e. Homo, Pan, Gorilla, Pongo). In the second part of the study, we examined shape variation among fossil mandibles assigned to Homo (including H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster, late African H. erectus, Asian H. erectus, H. heidelbergensis, H. neanderthalensis and H. sapiens). A novel randomization procedure designed for small samples (and using group 'distinctness values') was used to determine whether shape variation among the fossils is consistent with conventional taxonomy (or alternatively, whether a priori taxonomic groupings are completely random with respect to mandibular morphology). The randomization of 'distinctness values' was also used on the extant samples to assess the ability of the test to recognize known taxa. The discriminant analysis results demonstrated that, even for a relatively modest set of traditional mandibular corpus measurements, we can detect significant differences among extant hominids at the genus and species levels, and, in some cases, also at the subspecies level. Although the randomization of 'distinctness values' test is more conservative than discriminant analysis (based on comparisons with extant specimens), we were able to detect at least four distinct groups among the

Hominid mandibular corpus shape variation and its utility for recognizing species diversity within fossil Homo

Science.gov (United States)

Lague, Michael R; Collard, Nicole J; Richmond, Brian G; Wood, Bernard A

2008-01-01

Mandibular corpora are well represented in the hominin fossil record, yet few studies have rigorously assessed the utility of mandibular corpus morphology for species recognition, particularly with respect to the linear dimensions that are most commonly available. In this study, we explored the extent to which commonly preserved mandibular corpus morphology can be used to: (i) discriminate among extant hominid taxa and (ii) support species designations among fossil specimens assigned to the genus Homo. In the first part of the study, discriminant analysis was used to test for significant differences in mandibular corpus shape at different taxonomic levels (genus, species and subspecies) among extant hominid taxa (i.e. Homo, Pan, Gorilla, Pongo). In the second part of the study, we examined shape variation among fossil mandibles assigned to Homo(including H. habilis sensu stricto, H. rudolfensis, early African H. erectus/H. ergaster, late African H. erectus, Asian H. erectus, H. heidelbergensis, H. neanderthalensis and H. sapiens). A novel randomization procedure designed for small samples (and using group ‘distinctness values’) was used to determine whether shape variation among the fossils is consistent with conventional taxonomy (or alternatively, whether a priori taxonomic groupings are completely random with respect to mandibular morphology). The randomization of ‘distinctness values’ was also used on the extant samples to assess the ability of the test to recognize known taxa. The discriminant analysis results demonstrated that, even for a relatively modest set of traditional mandibular corpus measurements, we can detect significant differences among extant hominids at the genus and species levels, and, in some cases, also at the subspecies level. Although the randomization of ‘distinctness values’ test is more conservative than discriminant analysis (based on comparisons with extant specimens), we were able to detect at least four distinct groups

Late Pliocene Depositional History and Paleoclimate Reconstructions of the Southwest Pacific

Science.gov (United States)

Royce, B.; Patterson, M. O.; Pietras, J.

2017-12-01

Drift deposits off the eastern margin of New Zealand are important archives for the paleoclimate and paleoceanographic history of the southwest Pacific. Ocean Drilling Program (ODP) Site 1123 is located on the North Chatham rise drift just North of the westerly wind driven Subtropical Front (STF) and provides a record of near continuous sediment deposition since the Miocene along the southwest Pacific deep western boundary current (DWBC). While the Miocene and Late Pleistocene portion of this record have been well studied, the Late Pliocene record is less well developed. Southern Ocean geological records demonstrate that Late Pliocene cooling is the transient time bracketing the warmer than present Early Pliocene and bipolar glaciation at 2.7 Ma. A newly developed, robust, and astronomically tuned long-term record of benthic δ13C from ODP Site 1123 spanning the Early to Late Pliocene implies a reduction in Southern Ocean ventilation and lowering of preformed values from waters sourced along the Antarctic margin during the Late Pliocene. Thus, Late Pliocene Southern Hemisphere cooling and sea ice expansion may have drastically reduced outgassing and increased the burial of heat into the deep ocean. South Atlantic records off the west coast of Africa demonstrate an increase in the flux of iron to the open ocean during this time potentially enhancing surface ocean productivity and providing an additional cooling mechanism. Currently, atmospheric transport of dust to the Southern Ocean is dominated by persistent mid-latitude circumpolar westerly winds; this is particularly relevant for dust sourced from New Zealand. The Late Pliocene to Early Pleistocene uplift of the North Island axial ranges and South Island southern alps potentially provided a greater amount of not only sediment to the deep ocean, but also wind blow dust to the Pacific sector of the Southern Ocean. We will present a detailed high-resolution sedimentological study on the development of the Chatham

Discovery of novel isoforms of huntingtin reveals a new hominid-specific exon.

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Albert Ruzo

Full Text Available Huntington's disease (HD is a devastating neurological disorder that is caused by an expansion of the poly-Q tract in exon 1 of the Huntingtin gene (HTT. HTT is an evolutionarily conserved and ubiquitously expressed protein that has been linked to a variety of functions including transcriptional regulation, mitochondrial function, and vesicle transport. This large protein has numerous caspase and calpain cleavage sites and can be decorated with several post-translational modifications such as phosphorylations, acetylations, sumoylations, and palmitoylations. However, the exact function of HTT and the role played by its modifications in the cell are still not well understood. Scrutiny of HTT function has been focused on a single, full length mRNA. In this study, we report the discovery of 5 novel HTT mRNA splice isoforms that are expressed in normal and HTT-expanded human embryonic stem cell (hESC lines as well as in cortical neurons differentiated from hESCs. Interestingly, none of the novel isoforms generates a truncated protein. Instead, 4 of the 5 new isoforms specifically eliminate domains and modifications to generate smaller HTT proteins. The fifth novel isoform incorporates a previously unreported additional exon, dubbed 41b, which is hominid-specific and introduces a potential phosphorylation site in the protein. The discovery of this hominid-specific isoform may shed light on human-specific pathogenic mechanisms of HTT, which could not be investigated with current mouse models of the disease.

Discovery of Novel Isoforms of Huntingtin Reveals a New Hominid-Specific Exon

Science.gov (United States)

Popowski, Melissa; Haremaki, Tomomi; Croft, Gist F.; Deglincerti, Alessia; Brivanlou, Ali H.

2015-01-01

Huntington’s disease (HD) is a devastating neurological disorder that is caused by an expansion of the poly-Q tract in exon 1 of the Huntingtin gene (HTT). HTT is an evolutionarily conserved and ubiquitously expressed protein that has been linked to a variety of functions including transcriptional regulation, mitochondrial function, and vesicle transport. This large protein has numerous caspase and calpain cleavage sites and can be decorated with several post-translational modifications such as phosphorylations, acetylations, sumoylations, and palmitoylations. However, the exact function of HTT and the role played by its modifications in the cell are still not well understood. Scrutiny of HTT function has been focused on a single, full length mRNA. In this study, we report the discovery of 5 novel HTT mRNA splice isoforms that are expressed in normal and HTT-expanded human embryonic stem cell (hESC) lines as well as in cortical neurons differentiated from hESCs. Interestingly, none of the novel isoforms generates a truncated protein. Instead, 4 of the 5 new isoforms specifically eliminate domains and modifications to generate smaller HTT proteins. The fifth novel isoform incorporates a previously unreported additional exon, dubbed 41b, which is hominid-specific and introduces a potential phosphorylation site in the protein. The discovery of this hominid-specific isoform may shed light on human-specific pathogenic mechanisms of HTT, which could not be investigated with current mouse models of the disease. PMID:26010866

Late Pliocene diatoms in a diatomite from Prydz Bay, East Antarctica

Science.gov (United States)

Mahood, A.D.; Barron, J.A.

1996-01-01

Very well-preserved Pliocene diatoms from a diatomite unit interbedded within glacial sediments at Ocean Drilling Program Site 742 in Prydz Bay, Antarctica are documented and illustrated. The presence of Thalassiosira kolbei, T. torokina, Actinocyclus actinochilus, A. karstenii and the absence of Nitzschia interfrigidaria. T. insigna and T. vulnifica in Sample 119-742A-15R-4, 44-46cm constrain its age to ca. 2.2-1.8 Ma (late Pliocene). Diatoms associated with sea ice constitute 35% of the Pliocene diatom assemblage, compared with 71% of the modern sediment assemblage at the site, suggesting that sea ice was present during the late Pliocene period of deposition of the sample, although it probably was not the significant feature it is today. Thalassiosira ellitipora (Donahue) Fenner is described and illustrated in detail and is validly published. An expanded description and numerous illustrations are also presented for T. torokina Brady.

Stratigraphy, artefact industries and hominid associations for Sterkfontein, member 5.

Science.gov (United States)

Kuman, K; Clarke, R J

2000-06-01

A revised stratigraphy for the early hominid site of Sterkfontein (Gauteng Province, South Africa) reveals a complex distribution of infills in the main excavation area between 2.8 and 1.4 m.y.a, as well as deposits dating to the mid to late Pleistocene. New research now shows that the Member 4 australopithecine breccia (2.8-2.6 Ma) extends further west than was previously thought, while a late phase of Member 4 is recognized in a southern area. The artefact-bearing breccias were defined sedimentologically as Member 5, but one supposed part of these younger breccias, the StW 53 infill, lacks in situ stone tools, although it does appear to post-date 2.6 Ma when artefacts first appear in the archaeological record. The StW 53 hominid, previously referred to Homo habilis, is here argued to be Australopithecus. The first artefact-bearing breccia of Member 5 is the Oldowan Infill, estimated at 2-1.7 Ma. It occupies a restricted distribution in Member 5 east and contains an expedient, flake-based tool industry associated with a few fossils of Paranthropos robustus. An enlarged cave opening subsequently admitted one or more Early Acheulean infills associated in Member 5 west with Homo ergaster. The artefacts attest to a larger site accumulation between ca. 1.7 and 1.4 Ma, with more intensive use of quartzite over quartz and a subtle but important shift to large flakes and heavier-duty tools. The available information on palaeoenvironments is summarized, showing an overall change from tropical to sub-tropical gallery forest, forest fringe and woodland conditions in Member 4 to more open woodland and grassland habitats in the later units, but with suggestions of a wet localized topography in the Paranthropus -bearing Oldowan Infill. Copyright 2000 Academic Press.

Pliocene Warm Period Upwelling in the Southern Benguela Region

Science.gov (United States)

Petrick, B. F.; McClymont, E.; Felder, S.; Leng, M. J.; Rosell Mele, A.; Rueda, G.

2014-12-01

The mid-Pliocene has been proposed as a possible analogue for understanding future climate change and testing climate models. Previous work has shown that during the Pliocene the major upwelling systems were relatively warm, and thus either inactive, contracted, or upwelling warmer waters than present. Here we examine evidence from a core site located on the margins of the modern Benguela upwelling system, to test whether the upwelling cells had migrated or contracted relative to present during the Pliocene. We applied several organic geochemistry proxies and foraminiferal analyses to reconstruct the Pliocene history of ODP site 1087 (31º28'S, 15º19'E, 1374m water depth), including the UK37' index and TEX86 index (for reconstructing sea surface temperatures), chlorins (for estimating primary productivity) and planktonic foraminifera assemblages (for inferring water mass changes). These proxies show that between 3.5 and 3.0 Ma the southern Benguela region was significantly cooler than the northern Benguela region, the latter where the main upwelling cells are found today. Coupled with higher primary production, a shift in planktonic foraminifera assemblage, and an offset between the UK37' index and TEX86 index, we infer that more extensive upwelling was present in the southern Benguela region during the Pliocene. We infer that the main Benguela upwelling cells had shifted southward relative to today, as a result of changes in the local wind field. We find evidence for pronounced cooling and a shift in the planktonic foraminifera assemblage during the M2 and KM2 glacial stages, showing a sensitivity of Benguela upwelling to these short-lived climate events.

Ação do paradiclorobenzeno sôbre os cromossômios somáticos

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Cândida H. T. Mendes Conagin

1950-01-01

Full Text Available Neste trabalho são apresentados os resultados obtidos com Coffea arabica, Allium cepa, Arachis prostrata e Aloë sp., pela aplicação do processo Meyer para o estudo dos cromossômios somáticos. Em linhas gerais, o processo consta das seguintes fases : a tratamento de raízes por uma solução saturada de paradiclorobenzeno ; b fixação em Carnoy ; c hidrólise em HCl a 10%, a 60°C durante dois minutos ; d lavagens em água destilada ; e lavagens em ácido acético a 45% ; f coloração dos esfregaços pela orceína acética. Em virtude dêsse tratamento, os cromossômios se contraem e se apresentam bem separados nas placas metafásicas, sendo facilitada a sua determinação numérica. As constrições, a duplicidade e os satélites nos cromossômios, ficam também postos em evidência. Trata-se de um processo que pode substituir, com a vantagem da rapidez, o processo lento, de exame dos cromossômios somáticos por meio de cortes de material incluído em parafina, nas espécies estudadas.The effects of a prefixation treatment with paradichlorobenzene on the somatic chromosomes of Coffea arabica, Allium cepa, Arachis prostrata and Aloë sp. have been studied. The following schedule was followed for treating root tips : a prefixation in a solution of paradichlorobenzene ; b fixation in Carnoy ; c hydrolisis in 10 per cent HCI for two minutes at 60°C ; d washing in distilled water ; e washing in 45 per cent acetic acid ; f smearing and staining in aceto-orcein. Good smears were obtained with root tips of Coffea arabica, Allium cepa and Aloe sp. The chromosomes of Coffea arabica were well scattered in the cells. The long chromosomes of Allium cepa and Aloe sp. were also well separated from each other. No difference in the chromosomes was noticed in smears made from paradichlorobenzene treated and untreated root tips of Arachis prostrata. This technique can substitute the paraffin method to advantage for counting chromosome number in root tip

Workshop on Pliocene Climate

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Nabil Khélifi

2010-04-01

Full Text Available The warm Pliocene epoch (5–3 million years ago is often cited as a good analog for the near future climate because of its striking resemblance to the predictions of the “Intergovernmental Panel on Climate Change” for the next decades. Indeed, relative to today, during the Pliocene epoch, surface temperatures were 3–4°C warmer, sea level was about 5–40 meters higher, atmospheric CO2 concentrationswere relatively similar or slightly higher (~400 ± 50 ppmv, and ice sheets were restrained to Antarctica. However, since 3.0 Ma ago, the Earth’s climate has undergone a major transition from a warm and relatively stable state towards cold conditions marked by amplified glacial/interglacial cycles and widespread ice sheets in the Northern Hemisphere (NHG, and to a lesser extent over Antarctica. The causes and consequences of this global climate transition—driving warm periods to “icehouse” conditions marked by “Quaternary-style” glacial/interglacial cycles—are still uncertain. Yet, they may include the interaction of several mechanisms tied to oceanic and atmospheric circulations, tectonic-, greenhouse gases-, and biological activity, biogeochemical processes, and changes in Earth’s orbit.

On the age of the hominid fossils at the Sima de los Huesos, Sierra de Atapuerca, Spain: paleomagnetic evidence.

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Parés, J M; Pérez-González, A; Weil, A B; Arsuaga, J L

2000-04-01

We report new paleomagnetic data for the Middle Pleistocene hominid-bearing strata in the Sima de los Huesos, North Spain. Sediments (brown muds with human and bear fossils and the underlying sterile clayey and sandy unit) preserve both normal and reversed magnetic components. The sterile unit has exclusively reversed magnetization, dating back to the Matuyama Chron, and thus is Lower Pleistocene in age. The overlying fossiliferous muds have a dominant normal magnetization that overprints a partially resolved reversed magnetization. These data are compatible with one of the reversal events that occurred during the Brunhes Chron. Combined with the existing U-series dates and evidence from the macro- and microfauna, these paleomagnetic results suggest an age of the hominid fossils between 325 to 205 ka, whereas the underlying sand and silts are older than 780 ka. Copyright 2000 Wiley-Liss, Inc.

Snapshots of the Greenland ice sheet configuration in the Pliocene to early Pleistocene

DEFF Research Database (Denmark)

Solgaard, Anne M.; Reeh, Niels; Japsen, Peter

2011-01-01

The geometry of the ice sheets during the Pliocene to early Pleistocene is not well constrained. Here we apply an ice-flow model in the study of the Greenland ice sheet (GIS) during three extreme intervals of this period constrained by geological observations and climate reconstructions. We study...... the extent of the GIS during the Mid-Pliocene Warmth (3.3-3.0 Ma), its advance across the continental shelf during the late Pliocene to early Pleistocene glaciations (3.0-2.4 Ma) as implied by offshore geological studies, and the transition from glacial to interglacial conditions around 2.4 Ma as deduced...... the variability of the GIS during the Pliocene to early Pleistocene and underline the importance of including independent estimates of the GIS in studies of climate during this period. We conclude that the GIS did not exist throughout the Pliocene to early Pleistocene, and that it melted during interglacials even...

Accuracy in correlation and ecological aspects of the planktonic foraminiferal zonation of the mediterranean pliocene

NARCIS (Netherlands)

Spaak, P.

1982-01-01

Pliocene planktonic foraminiferal assoclatlOns from Cretan, Sicilian and Calabrian sections have been studied qualitatively and quantitatively in order to evaluate the Pliocene biozonation for the Mediterranean. Six zones can be clearly distinguished and in the middle part of the Pliocene a

Interproximal grooving in the Atapuerca-SH hominid dentitions.

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Bermúdez de Castro, J M; Arsuaga, J L; Pérez, P J

1997-03-01

The dental sample recovered from the Sima de los Huesos (SH) Middle Pleistocene cave site of the Sierra de Atapuerca (Spain) includes 296 specimens. Interproximal wear grooves have been observed in 20 maxillary and mandibular posterior teeth belonging to at least five of the 32 individuals identified so far in the SH hypodigm. Interproximal grooving affected only the adults, and at an age between 25 and 40 years. The appearance, morphology, and location pattern of the SH wear grooves are similar to those reported in other fossil hominids and in more recent human populations. Two alternative proposals, the toothpicking and the fiber or sinew processing hypotheses, compete for explaining the formation of this anomalous wear. The characteristics observed in the wear grooves of the SH teeth are compatible only with the habitual probing of interdental spaces by means of hard and inflexible objects. Dietary grit may also have contributed to the abrasion of the root walls during the motion of the dental probes.

Analysis of the dental morphology of Plio-pleistocene hominids. I. Mandibular molars: crown area measurements and morphological traits.

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Wood, B A; Abbott, S A

1983-01-01

This study has used accurate measurements of crown area and precise assessments of the morphological traits of mandibular molars in an attempt to define the metrical and morphological characteristics of early hominid taxa. A total of 196 Plio-Pleistocene hominid molars were either allocated to one of six informal taxonomic groups or considered as individual cases. Accurate measurements of crown base area made from occlusal photographs have enabled us to estimate the effects of interproximal wear on crown areas. The average correction factor over the three molar types is around 2-4% with a maximum of 6%. The patterns of distribution of extra cusps show interesting differences between taxa. None of the M-1S in the two groups of 'gracile' hominids from East and South Africa bears a C6, but it is common in the two 'robust' taxa. The distribution of a C7 is the reverse of this, it being rare in the robust' taxa, and more common in the 'gracile' groups. There is thus no simple relationship between cusp number and tooth size. Our observations on the protostylid suggest that though it is more common in the 'robust' australopithecines than the 'graciles', when it does occur it is more strongly expressed in the 'gracile' group. The combination of simple metrical data, and the assessment of morphological traits, can help in the classification of enigmatic or incomplete specimens. Some isolated teeth from the collection at Koobi Fora can confidently be assigned to Australopithecus boisei, and useful guides have been provided for taxonomic assessment of the skull KNM-ER 1805, and the mandibles KNM-ER 1506 and 1820.

Plegarias y fórmulas devotas en el Poema de Mio Cid

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Irene Zaderenko

2007-11-01

Full Text Available This article tackles the question of authorship in the Poema de mio Cid placing the poet in a monastery at the end of the twelfth century. The prayers that appear throughout the text show that the author was educated and devout, the characteristics of a clergyman. The knowledge of biblical events and the presence of words with their original Latin spellings in Jimena's prayer signal the ecclesiastical origins of the poem, probably in the monastery of Cardeña where the Cid was buried.

Data-Model Comparison of Pliocene Sea Surface Temperature

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Dowsett, H. J.; Foley, K.; Robinson, M. M.; Bloemers, J. T.

2013-12-01

The mid-Piacenzian (late Pliocene) climate represents the most geologically recent interval of long-term average warmth and shares similarities with the climate projected for the end of the 21st century. As such, its fossil and sedimentary record represents a natural experiment from which we can gain insight into potential climate change impacts, enabling more informed policy decisions for mitigation and adaptation. We present the first systematic comparison of Pliocene sea surface temperatures (SST) between an ensemble of eight climate model simulations produced as part of PlioMIP (Pliocene Model Intercomparison Project) and the PRISM (Pliocene Research, Interpretation and Synoptic Mapping) Project mean annual SST field. Our results highlight key regional (mid- to high latitude North Atlantic and tropics) and dynamic (upwelling) situations where there is discord between reconstructed SST and the PlioMIP simulations. These differences can lead to improved strategies for both experimental design and temporal refinement of the palaeoenvironmental reconstruction. Scatter plot of multi-model-mean anomalies (squares) and PRISM3 data anomalies (large blue circles) by latitude. Vertical bars on data anomalies represent the variability of warm climate phase within the time-slab at each locality. Small colored circles represent individual model anomalies and show the spread of model estimates about the multi-model-mean. While not directly comparable in terms of the development of the means nor the meaning of variability, this plot provides a first order comparison of the anomalies. Encircled areas are a, PRISM low latitude sites outside of upwelling areas; b, North Atlantic coastal sequences and Mediterranean sites; c, large anomaly PRISM sites from the northern hemisphere. Numbers identify Ocean Drilling Program sites.

Assessing Confidence in Pliocene Sea Surface Temperatures to Evaluate Predictive Models

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Dowsett, Harry J.; Robinson, Marci M.; Haywood, Alan M.; Hill, Daniel J.; Dolan, Aisling. M.; Chan, Wing-Le; Abe-Ouchi, Ayako; Chandler, Mark A.; Rosenbloom, Nan A.; Otto-Bliesner, Bette L.;

A pliocene cliff-line around the Giza Pyramids Plateau, Egypt

OpenAIRE

Aigner, Thomas

1982-01-01

Aigner, T., 1983. A Pliocene cliff-line around the Giza Pyramids Plateau, Egypt. Palaeogeogr., Palaeoclimatol., Palaeoecol., 4 2 : 313—322. Escarpments bordering the Giza Pyramids Plateau represent the cliff-line of a Pliocene transgression up the pre-Nile ("Eonile") Valley. Geomorphologically, a limestone cliff can be distinguished from a slip-block shore associated with a distinct fining-up sequence. Differences in bedrock lithology and in structure (Joint pattern, faults) are morphogen...

Changes in ocean circulation in the South-east Atlantic Ocean during the Pliocene

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Petrick, B. F.; McClymont, E.; Felder, S.; Leng, M. J.

2013-12-01

The Southeast Atlantic Ocean is an important ocean gateway because major oceanic systems interact with each other in a relatively small geographic area. These include the Benguela Current, Antarctic Circumpolar Current, and the input of warm and saline waters from the Indian Ocean via the Agulhas leakage. However, there remain questions about circulation change in this region during the Pliocene, including whether there was more or less Agulhas Leakage, which may have implications for the strength of the global thermohaline circulation. ODP Site 1087 (31°28'S, 15°19'E, 1374m water depth) is located outside the Benguela upwelling region and is affected by Agulhas leakage in the modern ocean. Sea-surface temperatures (SSTs) are thus sensitive to the influence of Agulhas Leakage at this site. Our approach is to apply several organic geochemistry proxies and foraminiferal analyses to reconstruct the Pliocene history of ODP 1087, including the UK37' index (SSTs), pigments (primary productivity) and planktonic foraminifera (water mass changes). SSTs during the Pliocene range from 17 to 22.5 °C (mean SSTs at 21 °C), and show variability on orbital and suborbital time scales. Our results indicate that the Benguela upwelling system had intensified and/or shifted south during the Pliocene. We find no evidence of Agulhas leakage, meaning that either Agulhas Leakage was severely reduced or displaced during the mid-Pliocene. Potential causes of the observed signals include changes to the local wind field and/or changes in the temperature of intermediate waters which upwell in the Benguela system. Pronounced cooling is observed during cold stages in the Pliocene, aligned with the M2 and KM2 events. These results may indicate that changes to the extent of the Antarctic ice sheet had impact on circulation in the south east Atlantic during the Pliocene via displacement of the Antarctic Circumpolar Currents.

Hominid evolution: genetics versus memetics

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Carter, Brandon

2012-01-01

The last few million years on planet Earth have witnessed two remarkable phases of hominid development, starting with a phase of biological evolution characterized by rather rapid increase of the size of the brain. This has been followed by a phase of even more rapid technological evolution and concomitant expansion of the size of the population that began when our own particular ‘sapiens’ species emerged, just a few hundred thousand years ago. The present investigation exploits the analogy between the neo-Darwinian genetic evolution mechanism governing the first phase, and the memetic evolution mechanism governing the second phase. From the outset of the latter until very recently - about the year 2000 - the growth of the global population N was roughly governed by an equation of the form dN/Ndt=N/T*, in which T* is a coefficient introduced (in 1960) by von Foerster, who evaluated it empirically as about 200 000 million years. It is shown here how the value of this hitherto mysterious timescale governing the memetic phase is explicable in terms of what happened in the preceding genetic phase. The outcome is that the order of magnitude of the Foerster timescale can be accounted for as the product of the relevant (human) generation timescale, about 20 years, with the number of bits of information in the genome, of the order of 10 000 million. Whereas the origin of our ‘homo’ genus may well have involved an evolutionary hard step, it transpires that the emergence of our particular ‘sapiens’ species was rather an automatic process.

Analyses of plant biomarkers in modern ecosystems to improve vegetation reconstructions at hominid sites

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Uno, K. T.; Boisserie, J. R.; Cerling, T. E.; Polissar, P. J.

2017-12-01

Reconstructing vegetation at hominid localities in eastern Africa remains a significant challenge for examining the role of climate and environment in human evolution. Plant wax biomarker approaches, particularly carbon isotopes of n-alkyl lipids, have been increasingly used to estimate the proportion of C3 and C4­ vegetation in past environments. Identifying new biomarkers indicative of vegetation type, specifically those that can be used to identify (C3) grasses prior to the late Miocene C4 expansion, will enable vegetation reconstructions during the first half of the Neogene, where much remains to be learned about hominid environments. Here, we begin to look beyond carbon isotopes from n-alkyl lipids by analyzing molecular distributions and screening for new plant biomarkers that can be used to identify plant functional types or possibly, more specific taxonomic information. We evaluate molecular distributions, carbon isotope ratios, and pentacyclic triterpenoid methyl esters (PTMEs) in modern soils from a wide range of ecosystems in Ethiopia and Kenya where vegetation types, fraction woody cover, and climatic conditions are known. Preliminary data suggest PTMEs are associated with grassy ecosystems but absent from forested ones. We also find that woody cover can be estimated using n-alkane molecular distributions. This non-isotopic approach to reconstructing woody cover opens the door to reconstructing Neogene vegetation provided the molecular distributions of C3 grasses in the past are similar to those of modern C4 grasses.

A new horned crocodile from the Plio-Pleistocene hominid sites at Olduvai Gorge, Tanzania.

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Christopher A Brochu

Full Text Available BACKGROUND: The fossil record reveals surprising crocodile diversity in the Neogene of Africa, but relationships with their living relatives and the biogeographic origins of the modern African crocodylian fauna are poorly understood. A Plio-Pleistocene crocodile from Olduvai Gorge, Tanzania, represents a new extinct species and shows that high crocodylian diversity in Africa persisted after the Miocene. It had prominent triangular "horns" over the ears and a relatively deep snout, these resemble those of the recently extinct Malagasy crocodile Voay robustus, but the new species lacks features found among osteolaemines and shares derived similarities with living species of Crocodylus. METHODOLOGY/PRINCIPAL FINDINGS: The holotype consists of a partial skull and skeleton and was collected on the surface between two tuffs dated to approximately 1.84 million years (Ma, in the same interval near the type localities for the hominids Homo habilis and Australopithecus boisei. It was compared with previously-collected material from Olduvai Gorge referable to the same species. Phylogenetic analysis places the new form within or adjacent to crown Crocodylus. CONCLUSIONS/SIGNIFICANCE: The new crocodile species was the largest predator encountered by our ancestors at Olduvai Gorge, as indicated by hominid specimens preserving crocodile bite marks from these sites. The new species also reinforces the emerging view of high crocodylian diversity throughout the Neogene, and it represents one of the few extinct species referable to crown genus Crocodylus.

Auditory ERPs to stimulus deviance in an awake chimpanzee (Pan troglodytes: towards hominid cognitive neurosciences.

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Ari Ueno

Full Text Available BACKGROUND: For decades, the chimpanzee, phylogenetically closest to humans, has been analyzed intensively in comparative cognitive studies. Other than the accumulation of behavioral data, the neural basis for cognitive processing in the chimpanzee remains to be clarified. To increase our knowledge on the evolutionary and neural basis of human cognition, comparative neurophysiological studies exploring endogenous neural activities in the awake state are needed. However, to date, such studies have rarely been reported in non-human hominid species, due to the practical difficulties in conducting non-invasive measurements on awake individuals. METHODOLOGY/PRINCIPAL FINDINGS: We measured auditory event-related potentials (ERPs of a fully awake chimpanzee, with reference to a well-documented component of human studies, namely mismatch negativity (MMN. In response to infrequent, deviant tones that were delivered in a uniform sound stream, a comparable ERP component could be detected as negative deflections in early latencies. CONCLUSIONS/SIGNIFICANCE: The present study reports the MMN-like component in a chimpanzee for the first time. In human studies, various ERP components, including MMN, are well-documented indicators of cognitive and neural processing. The results of the present study validate the use of non-invasive ERP measurements for studies on cognitive and neural processing in chimpanzees, and open the way for future studies comparing endogenous neural activities between humans and chimpanzees. This signifies an essential step in hominid cognitive neurosciences.

Climatic implications of reconstructed early - Mid Pliocene equilibrium-line altitudes in the McMurdo Dry Valleys, Antarctica

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Krusic, A.G.; Prentice, M.L.; Licciardi, J.M.

2009-01-01

Early-mid Pliocene moraines in the McMurdo Dry Valleys, Antarctica, are more extensive than the present alpine glaciers in this region, indicating substantial climatic differences between the early-mid Pliocene and the present. To quantify this difference in the glacier-climate regime, we estimated the equilibrium-line altitude (ELA) change since the early-mid Pliocene by calculating the modern ELA and reconstructing the ELAs of four alpine glaciers in Wright and Taylor Valleys at their early-mid Pliocene maxima. The area-altitude balance ratio method was used on modern and reconstructed early-mid Pliocene hypsometry. In Wright and Victoria Valleys, mass-balance data identify present-day ELAs of 800-1600 m a.s.l. and an average balance ratio of 1.1. The estimated ELAs of the much larger early-mid Pliocene glaciers in Wright and Taylor Valleys range from 600 to 950 ?? 170 m a.s.l., and thus are 250-600 ??170 m lower than modern ELAs in these valleys. The depressed ELAs during the early-mid-Pliocene most likely indicate a wetter and therefore warmer climate in the Dry Valleys during this period than previous studies have recognized.

Patterns of myoxid evolution in the Pliocene and Pleistocene of Europe

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Adam Nadachoswki

1995-05-01

Full Text Available Abstract The origin of recent species belonging to the genera Myoxus, Muscardinus, Glirulus, Eliomys, Dryomys and Myomimus is discussed. Evolution of myoxids in the Pliocene and Pleistocene is expressed by gradual size increase of their cheek teeth. No gradual change in the dental pattern is observed. Riassunto Modelli di evoluzione dei Mioxidi nel Pliocene e Pleistocene in Europa - Viene discussa l'origine delle specie recenti appartenenti ai generi Myoxus, Muscardinus, Glirulus, Eliomys, Dryomys e Myomimus. L'evoluzione dei Mioxidi nel Pliocene e nel Pleistocene è espressa da un graduale aumento delle dimensioni dei molari. Non è stato osservato alcun cambiamento graduale nel pattern dentale.

Mid-Pliocene equatorial Pacific sea surface temperature reconstruction: a multi-proxy perspective

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Dowsett, Harry J.; Robinson, Marci M.

2009-01-01

The Mid-Pliocene is the most recent interval of sustained global warmth, which can be used to examine conditions predicted for the near future. An accurate spatial representation of the low-latitude Mid-Pliocene Pacific surface ocean is necessary to understand past climate change in the light of forecasts of future change. Mid-Pliocene sea surface temperature (SST) anomalies show a strong contrast between the western equatorial Pacific (WEP) and eastern equatorial Pacific (EEP) regardless of proxy (faunal, alkenone and Mg/Ca). All WEP sites show small differences from modern mean annual temperature, but all EEP sites show significant positive deviation from present-day temperatures by as much as 4.4°C. Our reconstruction reflects SSTs similar to modern in the WEP, warmer than modern in the EEP and eastward extension of the WEP warm pool. The east-west equatorial Pacific SST gradient is decreased, but the pole to equator gradient does not change appreciably. We find it improbable that increased greenhouse gases (GHG) alone would cause such a heterogeneous warming and more likely that the cause of Mid-Pliocene warmth is a combination of several forcings including both increased meridional heat transport and increased GHG.

Hybrid insolation forcing of Pliocene monsoon dynamics in West Africa

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R. R. Kuechler

2018-01-01

Full Text Available The Pliocene is regarded as a potential analogue for future climate with conditions generally warmer-than-today and higher-than-preindustrial atmospheric CO2 levels. Here we present the first orbitally resolved records of continental hydrology and vegetation changes from West Africa for two Pliocene time intervals (5.0–4.6 Ma, 3.6–3.0 Ma, which we compare with records from the last glacial cycle (Kuechler et al., 2013. Our results indicate that changes in local insolation alone are insufficient to explain the full degree of hydrologic variations. Generally two modes of interacting insolation forcings are observed: during eccentricity maxima, when precession was strong, the West African monsoon was driven by summer insolation; during eccentricity minima, when precession-driven variations in local insolation were minimal, obliquity-driven changes in the summer latitudinal insolation gradient became dominant. This hybrid monsoonal forcing concept explains orbitally controlled tropical climate changes, incorporating the forcing mechanism of latitudinal gradients for the Pliocene, which probably increased in importance during subsequent Northern Hemisphere glaciations.

Bathymetric controls on Pliocene North Atlantic and Arctic sea surface temperature and deepwater production

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Robinson, M.M.; Valdes, P.J.; Haywood, A.M.; Dowsett, H.J.; Hill, D.J.; Jones, S.M.

2011-01-01

The mid-Pliocene warm period (MPWP; ~. 3.3 to 3.0. Ma) is the most recent interval in Earth's history in which global temperatures reached and remained at levels similar to those projected for the near future. The distribution of global warmth, however, was different than today in that the high latitudes warmed more than the tropics. Multiple temperature proxies indicate significant sea surface warming in the North Atlantic and Arctic Oceans during the MPWP, but predictions from a fully coupled ocean-atmosphere model (HadCM3) have so far been unable to fully predict the large scale of sea surface warming in the high latitudes. If climate proxies accurately represent Pliocene conditions, and if no weakness exists in the physics of the model, then model boundary conditions may be in error. Here we alter a single boundary condition (bathymetry) to examine if Pliocene high latitude warming was aided by an increase in poleward heat transport due to changes in the subsidence of North Atlantic Ocean ridges. We find an increase in both Arctic sea surface temperature and deepwater production in model experiments that incorporate a deepened Greenland-Scotland Ridge. These results offer both a mechanism for the warming in the North Atlantic and Arctic Oceans indicated by numerous proxies and an explanation for the apparent disparity between proxy data and model simulations of Pliocene northern North Atlantic and Arctic Ocean conditions. Determining the causes of Pliocene warmth remains critical to fully understanding comparisons of the Pliocene warm period to possible future climate change scenarios. ?? 2011.

Active Pacific meridional overturning circulation (PMOC) during the warm Pliocene.

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Burls, Natalie J; Fedorov, Alexey V; Sigman, Daniel M; Jaccard, Samuel L; Tiedemann, Ralf; Haug, Gerald H

2017-09-01

An essential element of modern ocean circulation and climate is the Atlantic meridional overturning circulation (AMOC), which includes deep-water formation in the subarctic North Atlantic. However, a comparable overturning circulation is absent in the Pacific, the world's largest ocean, where relatively fresh surface waters inhibit North Pacific deep convection. We present complementary measurement and modeling evidence that the warm, ~400-ppmv (parts per million by volume) CO 2 world of the Pliocene supported subarctic North Pacific deep-water formation and a Pacific meridional overturning circulation (PMOC) cell. In Pliocene subarctic North Pacific sediments, we report orbitally paced maxima in calcium carbonate accumulation rate, with accompanying pigment and total organic carbon measurements supporting deep-ocean ventilation-driven preservation as their cause. Together with high accumulation rates of biogenic opal, these findings require vigorous bidirectional communication between surface waters and interior waters down to ~3 km in the western subarctic North Pacific, implying deep convection. Redox-sensitive trace metal data provide further evidence of higher Pliocene deep-ocean ventilation before the 2.73-Ma (million years) transition. This observational analysis is supported by climate modeling results, demonstrating that atmospheric moisture transport changes, in response to the reduced meridional sea surface temperature gradients of the Pliocene, were capable of eroding the halocline, leading to deep-water formation in the western subarctic Pacific and a strong PMOC. This second Northern Hemisphere overturning cell has important implications for heat transport, the ocean/atmosphere cycle of carbon, and potentially the equilibrium response of the Pacific to global warming.

Evaluating the Dominant Components of Warming in Pliocene Climate Simulations

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Hill, D. J.; Haywood, A. M.; Lunt, D. J.; Hunter, S. J.; Bragg, F. J.; Contoux, C.; Stepanek, C.; Sohl, L.; Rosenbloom, N. A.; Chan, W.-L.;

The 'temporal effect' in hominids: Reinvestigating the nature of support for a chimp-human clade in bone morphology.

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Pearson, Alannah; Groves, Colin; Cardini, Andrea

2015-11-01

In 2004, an analysis by Lockwood and colleagues of hard-tissue morphology, using geometric morphometrics on the temporal bone, succeeded in recovering the correct phylogeny of living hominids without resorting to potentially problematic methods for transforming continuous shape variables into meristic characters. That work has increased hope that by using modern analytical methods and phylogenetically informative anatomical data we might one day be able to accurately infer the relationships of hominins, including the closest extinct relatives of modern humans. In the present study, using 3D virtually generated models of the hominid temporal bone and a larger suite of geometric morphometric and comparative techniques, we have re-examined the evidence for a Pan-Homo clade. Despite differences in samples, as well as the type of raw data, the effect of measurement error (and especially landmark digitization by a different operator), but also a broader perspective brought in by our diverse set of approaches, our reanalysis largely supports Lockwood and colleagues' original results. However, by focusing not only mainly on shape (as in the original 2004 analysis) but also on size and 'size-corrected' (non-allometric) shape, we demonstrate that the strong phylogenetic signal in the temporal bone is largely related to similarities in size. Thus, with this study, we are not suggesting the use of a single 'character', such as size, for phylogenetic inference, but we do challenge the common view that shape, with its highly complex and multivariate nature, is necessarily more phylogenetically informative than size and that actually size and size-related shape variation (i.e., allometry) confound phylogenetic inference based on morphology. This perspective may in fact be less generalizable than often believed. Thus, while we confirm the original findings by Lockwood et al., we provide a deep reinterpretation of their nature and potential implications for hominid phylogenetics

Increased ventilation of Antarctic deep water during the warm mid-Pliocene.

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Zhang, Zhongshi; Nisancioglu, Kerim H; Ninnemann, Ulysses S

2013-01-01

The mid-Pliocene warm period is a recent warm geological period that shares similarities with predictions of future climate. It is generally held the mid-Pliocene Atlantic Meridional Overturning Circulation must have been stronger, to explain a weak Atlantic meridional δ(13)C gradient and large northern high-latitude warming. However, climate models do not simulate such stronger Atlantic Meridional Overturning Circulation, when forced with mid-Pliocene boundary conditions. Proxy reconstructions allow for an alternative scenario that the weak δ(13)C gradient can be explained by increased ventilation and reduced stratification in the Southern Ocean. Here this alternative scenario is supported by simulations with the Norwegian Earth System Model (NorESM-L), which simulate an intensified and slightly poleward shifted wind field off Antarctica, giving enhanced ventilation and reduced stratification in the Southern Ocean. Our findings challenge the prevailing theory and show how increased Southern Ocean ventilation can reconcile existing model-data discrepancies about Atlantic Meridional Overturning Circulation while explaining fundamental ocean features.

Pliocene palaeoceanography of the Arctic Ocean and subarctic seas.

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Matthiessen, Jens; Knies, Jochen; Vogt, Christoph; Stein, Ruediger

2009-01-13

The Pliocene is important in the geological evolution of the high northern latitudes. It marks the transition from restricted local- to extensive regional-scale glaciations on the circum-Arctic continents between 3.6 and 2.4Ma. Since the Arctic Ocean is an almost land-locked basin, tectonic activity and sea-level fluctuations controlled the geometry of ocean gateways and continental drainage systems, and exerted a major influence on the formation of continental ice sheets, the distribution of river run-off, and the circulation and water mass characteristics in the Arctic Ocean. The effect of a water mass exchange restricted to the Bering and Fram Straits on the oceanography is unknown, but modelling experiments suggest that this must have influenced the Atlantic meridional overturning circulation. Cold conditions associated with perennial sea-ice cover might have prevailed in the central Arctic Ocean throughout the Pliocene, whereas colder periods alternated with warmer seasonally ice-free periods in the marginal areas. The most pronounced oceanographic change occurred in the Mid-Pliocene when the circulation through the Bering Strait reversed and low-salinity waters increasingly flowed from the North Pacific into the Arctic Ocean. The excess freshwater supply might have facilitated sea-ice formation and contributed to a decrease in the Atlantic overturning circulation.

Geometric morphometric analysis of allometric variation in the mandibular morphology of the hominids of Atapuerca, Sima de los Huesos site.

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Rosas, Antonio; Bastir, Markus

2004-06-01

Allometry is an important factor of morphological integration that contributes to the organization of the phenotype and its variation. Variation in the allometric shape of the mandible is particularly important in hominid evolution because the mandible carries important taxonomic traits. Some of these traits are known to covary with size, particularly the retromolar space, symphyseal curvature, and position of the mental foramen. The mandible is a well studied system in the context of the evolutionary development of complex morphological structures because it is composed of different developmental units that are integrated within a single bone. In the present study, we investigated the allometric variation of two important developmental units that are separated by the inferior nerve (a branch of CN V3). We tested the null hypothesis that there would be no difference in allometric variation between the two components. Procrustes-based geometric morphometrics of 20 two-dimensional (2D) landmarks were analyzed by multivariate regressions of shape on size in samples from 121 humans, 48 chimpanzees, and 50 gorillas (all recent specimens), eight fossil hominids from Atapuerca, Sima de los Huesos (AT-SH), and 17 Neandertals. The findings show that in all of the examined species, there was significantly greater allometric variation in the supra-nerve unit than in the infra-nerve unit. The formation of the retromolar space exhibited an allometric relationship with the supra-nerve unit in all of the species studied. The formation of the chin-like morphology is an "apodynamic" feature of the infra-nerve unit in the AT-SH hominids. The results of this study support the hypothesis that allometry contributes to the organization of variation in complex morphological structures. Copyright 2004 Wiley-Liss, Inc.

Recent work on network application layer: MioNet, the virtual workplace for small businesses

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Hesselink, Lambertus; Rizal, Dharmarus; Bjornson, Eric; Miller, Brian; Chan, Keith

2005-11-01

Small businesses must be extremely efficient and smartly leverage their resources, suppliers, and partners to successfully compete with larger firms. A successful small business requires a set of companies with interlocking business relationships that are dynamic and needs-based. There has been no software solution that creates a secure and flexible way to efficiently connect small business computer-based employees and partners. In this invited paper, we discuss MioNet, a secure and powerful data management platform which may provide millions of small businesses with a virtual workplace and help them to succeed.

AN ANALYTIC OUTLOOK OF THE MADRIGAL MORO LASSO AL MIO DUOLO BY GESUALDO DA VENOSA

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MURARU AUREL

2015-09-01

Full Text Available The analysis of the madrigal Moro lasso al mio duolo reveals the melancholic, thoughtful and grieving atmosphere, gene­rating shady, silent, sometimes dark soundscapes. Gesualdo shapes the poliphony through chromatic licenses, in order to create a tense musical discourse, permanently yearning for stability and balance amidst a harmonic construction lacking any attempt for resolution. Thus the strange harmonies of Gesualdo are shaped, giving birth to a unique musical style, full of dissonances and endless musical tension.

Aleksander Wat. Mój wiek (1977 - Il mio secolo (2013. Premessa

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Luigi Marinelli

2013-03-01

Full Text Available At the beginning of the 1960s Czesław Miłosz recorded Aleksander Wat’s memories on tape. The recordings were then published with the title Moj Wiek (1977 and translated into many languages. A real “Odyssey of a Polish intellectual”, as the subtitle of the American version (1988 suggested, Wat’s memoir is regarded as one of the most important testimonies of the atrocities of the last century. Finally, after many years, it has been translated into Italian, and will be published in the Spring of 2013. An excerpt from Il mio secolo is published in this article with permission from the Sellerio publishing house. It is taken from the eighteenth chapter, where Wat describes the first Soviet jail in which he was detained.

Using tetraether lipids archived in North Sea Basin sediments to extract North Western European Pliocene continental air temperatures

Science.gov (United States)

Dearing Crampton-Flood, Emily; Peterse, Francien; Munsterman, Dirk; Sinninghe Damsté, Jaap S.

2018-05-01

The Pliocene is often regarded as a suitable analogue for future climate, due to an overall warmer climate (2-3 °C) coupled with atmospheric CO2 concentrations largely similar to present values (∼400 ppmv). Numerous Pliocene sea surface temperature (SST) records are available, however, little is known about climate in the terrestrial realm. Here we generated a Pliocene continental temperature record for Northwestern Europe based on branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids stored in a marine sedimentary record from the western Netherlands. The total organic carbon (TOC) content of the sediments and its stable carbon isotopic composition (δ13Corg) indicate a strong transition from primarily marine derived organic matter (OM) during the Pliocene, to predominantly terrestrially derived OM after the transition into the Pleistocene. This trend is supported by the ratio of branched and isoprenoid tetraethers (BIT index). The marine-terrestrial transition indicates a likely change in brGDGT sources in the core, which may complicate the applicability of the brGDGT paleotemperature proxy in this setting. Currently, the application of the brGDGT-based paleothermometer on coastal marine sediments has been hampered by a marine overprint. Here, we propose a method to disentangle terrestrial and marine sources based on the degree of cyclization of tetramethylated brGDGTs (#rings) using a linear mixing model based on the global soil calibration set and a newly developed coastal marine temperature transfer function. Application of this method on our brGDGT record resulted in a 'corrected' terrestrial temperature record (MATterr). This latter record indicates that continental temperatures were ∼12-14 °C during the Early Pliocene, and 10.5-12 °C during the Mid Pliocene, confirming other Pliocene pollen based terrestrial temperature estimates from Northern and Central Europe. Furthermore, two colder (Δ 5-7 °C) periods in the Pliocene MATterr

The Sima de los Huesos hominids date to beyond U/Th equilibrium (>350 kyr) and perhaps to 400-500 kyr: New radiometric dates

Science.gov (United States)

Bischoff, J.L.; Shamp, D.D.; Aramburu, Arantza; Arsuaga, J.L.; Carbonell, E.; Bermudez de Castro, Jose Maria

2003-01-01

The Sima de los Huesos site of the Atapuerca complex near Burgos, Spain contains the skeletal remains of at least 28 individuals in a mud breccia underlying an accumulation of the Middle Pleistocene cave bear (U. deningeri). Earlier dating estimates of 200 to 320 kyr were based on U-series and ESR methods applied to bones, made inaccurate by unquantifiable uranium cycling. We report here on a new discovery within the Sima de los Huesos of human bones stratigraphically underlying an in situ speleothem. U-series analyses of the speleothem shows the lower part to be at isotopic U/Th equilibrium, translating to a firm lower limit of 350 kyr for the SH hominids. Finite dates on the upper part suggest a speleothem growth rate of c. 1 cm/32 kyr. This rate, along with paleontological constraints, place the likely age of the hominids in the interval of 400 to 600 kyr. ?? 2002 Elsevier Science Ltd. All rights reserved.

Fire in the Pliocene: a Record from the Southwest Pacific Ocean

Science.gov (United States)

Rosell-Melé, A.; Moraleda, N.; Peterson, L.; Lawrence, K. T.

2015-12-01

There is a growing recognition of the importance of wildfires in the Earth system. The IPCC 5AR concluded that extensive areas of the world will increase substantially their probability to fire in the near future. This issue is of difficult evaluation given the multiplicity drivers of fire, including anthropogenic factors, and because fire was impossible to observe and analyse as a global phenomenon until well into the satellite era. The study of the Pliocene may however afford some glimpses to this issue as one of the best ancient-climate analogues of present-day and future greenhouse-warming conditions. The incidence of fire in the Pliocene has not been assessed in much detail. In fact, fossil evidence for fire activity over the last 50+ Ma from the Eocene through to the present day is scant, and is chiefly based on the presence of charred materials, or charcoal, which provides a partial perspective of fire occurrence, and the development of pyrophytic biomes such as savannahs and shrublands. Marine charcoal records, from widely separated geographic regions (North Pacific, Eastern south Atlantic, South China Sea), indicate low but significant fire activity throughout the Cenozoic until the late Miocene or Pliocene, when it increased, sometimes together with the rise of pyrophytic biomes. An alternative to the study of charcoal records is the analysis of polyaromatic hydrocarbons (PAHs), which are also generated in biomass combustion processes but are associated to soot and integrate the occurrence of fire over large regional provinces. One of the most abundant is retene, formed from the thermal degradation of resins. We have quantified PAHs in Site ODP 1125 which spans the Pliocene-Pleistocene, on the north slope of Chatham Rise, 600 km east of New Zealand's South Island. PAHs have been identified throughout the record, and namely during colder climatic episodes. Their abundance appears tightly linked to that of other terrigenous biomarkers like the n

Recidiva criminal em 100 internos do Manicômio Judiciário de Franco da Rocha

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Moscatello Roberto

2001-01-01

Full Text Available OBJETIVOS: Verificar a ocorrência de comportamento criminal recidivo em uma população de internos do Manicômio Judiciário de Franco da Rocha. MÉTODOS: Cem internos de um Manicômio Judiciário em cumprimento de medida de segurança foram entrevistados, sendo todos do sexo masculino e com idades variando de 26 a 80 anos. Os diagnósticos preencheram critérios da CID-10, e os delitos cometidos foram verificados segundo o Código Penal Brasileiro. RESULTADOS: Dos 100 internos avaliados, 41% cometeram um crime, e 59% cometeram mais de um crime. As psicoses esquizofrênicas foram os diagnósticos mais freqüentes nos internos que cometeram um crime e naqueles que cometeram mais de um crime. Os diagnósticos retardo mental e transtornos de personalidade seguiram em freqüência nos que cometeram um crime. Transtornos de personalidade e retardo mental foram os diagnósticos que seguiram em freqüencia nos que cometeram mais de um crime. CONCLUSÕES: As psicoses esquizofrênicas predominaram nos internos avaliados. Crimes contra a vida foram mais comuns entre os que cometeram um crime, enquanto crimes contra o patrimônio predominaram entre os que cometeram mais de um crime.

Pliocene warmth, polar amplification, and stepped Pleistocene cooling recorded in NE Arctic Russia.

Science.gov (United States)

Brigham-Grette, Julie; Melles, Martin; Minyuk, Pavel; Andreev, Andrei; Tarasov, Pavel; DeConto, Robert; Koenig, Sebastian; Nowaczyk, Norbert; Wennrich, Volker; Rosén, Peter; Haltia, Eeva; Cook, Tim; Gebhardt, Catalina; Meyer-Jacob, Carsten; Snyder, Jeff; Herzschuh, Ulrike

2013-06-21

Understanding the evolution of Arctic polar climate from the protracted warmth of the middle Pliocene into the earliest glacial cycles in the Northern Hemisphere has been hindered by the lack of continuous, highly resolved Arctic time series. Evidence from Lake El'gygytgyn, in northeast (NE) Arctic Russia, shows that 3.6 to 3.4 million years ago, summer temperatures were ~8°C warmer than today, when the partial pressure of CO2 was ~400 parts per million. Multiproxy evidence suggests extreme warmth and polar amplification during the middle Pliocene, sudden stepped cooling events during the Pliocene-Pleistocene transition, and warmer than present Arctic summers until ~2.2 million years ago, after the onset of Northern Hemispheric glaciation. Our data are consistent with sea-level records and other proxies indicating that Arctic cooling was insufficient to support large-scale ice sheets until the early Pleistocene.

Higher plant vegetation changes during Pliocene sapropel formation

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Menzel, D.; Schouten, S.; Bergen, P.F. van

2004-01-01

The 13C values of higher plant wax C27 33 n-alkanes were determined in three, time-equivalent Pliocene (2.943 Ma) sapropels and homogeneous calcareous ooze from three different sites forming an east-west transect in the eastern Mediterranean Basin in order to study the composition of the vegetation

El discutido influjo de la Historia Roderici en el Cantar de mio Cid

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Salvatore Luongo

2013-06-01

Full Text Available La hipótesis de una relación entre el Cantar de mio Cid y la Historia Roderici ha suscitado, como es sabido, una discusión animada que a día de hoy todavía no ha cesado. La presente contribución pretende volver a examinar la cuestión analizando de nuevo dos pasajes de la biografía poética de Rodrigo Díaz para los que se sospecha que se utilizó su biografía historiográfica: la exposición del conflicto con el conde barcelonés Ramón Berenguer y la exposición de la victoria del Campeador sobre el rey de Marruecos Yūsuf. El análisis revela una serie de correspondencias a distintos niveles (de organización estructural, de contenido, de unidades conceptuales menores, fraseológico, verbal que parecería confirmar un contacto directo entre los dos textos.L’hypothèse d’un rapport entre le Cantar de mio Cid et l’Historia Roderici a soulevé, comme on sait, une querelle vive et encore irrésolue. Cette étude se propose de revisiter la question en soumettant à un nouvel examen deux passages de la biographie poétique de Rodrigo Díaz pour lesquels l’utilisation de sa biographie historiographique a été soupçonnée: le récit du conflit avec le comte Barcelonais Ramón Berenguer et celui de la victoire du Campeador sur le roi du Maroc Yūsuf. L’analyse révèle une série de corrélations à plusieurs niveaux (d’organisation structurelle, de contenu, d’unités conceptuelles mineures, phraséologique, verbal qui semblerait confirmer un contact direct entre les deux textes.

Early Pliocene onset of modern Nordic Seas circulation related to ocean gateway changes.

Science.gov (United States)

De Schepper, Stijn; Schreck, Michael; Beck, Kristina Marie; Matthiessen, Jens; Fahl, Kirsten; Mangerud, Gunn

2015-10-28

The globally warm climate of the early Pliocene gradually cooled from 4 million years ago, synchronous with decreasing atmospheric CO2 concentrations. In contrast, palaeoceanographic records indicate that the Nordic Seas cooled during the earliest Pliocene, before global cooling. However, a lack of knowledge regarding the precise timing of Nordic Seas cooling has limited our understanding of the governing mechanisms. Here, using marine palynology, we show that cooling in the Nordic Seas was coincident with the first trans-Arctic migration of cool-water Pacific mollusks around 4.5 million years ago, and followed by the development of a modern-like Nordic Seas surface circulation. Nordic Seas cooling precedes global cooling by 500,000 years; as such, we propose that reconfiguration of the Bering Strait and Central American Seaway triggered the development of a modern circulation in the Nordic Seas, which is essential for North Atlantic Deep Water formation and a precursor for more widespread Greenland glaciation in the late Pliocene.

ESR analyses on tooth enamel from the Paleolithic layers at the Obi-Rakhmat hominid site, Uzbekistan: Tackling a dating controversy

International Nuclear Information System (INIS)

Skinner, Anne R.; Blackwell, Bonnie A.B.; Mian, Abubakar; Baboumian, Shaunte M.; Blickstein, Joel I.B.; Wrinn, Patrick J.; Krivoshapkin, A.I.; Derevianko, A.P.; Lundburg, Joyce A.

2007-01-01

In the Tien Shan Mt., northeastern Uzbekistan, the Obi-Rakhmat rockshelter has yielded newly discovered hominid remains associated with an abundant Paleolithic industry and a rich faunal assemblage in typical cave fill sediment. Eight bovid teeth were dated by standard and isochron ESR to resolve the 50 ky discrepancy between the 14 C and 234 Th/ 234 U ages for Obi-Rakhmat. All the dentine contained high U concentrations, up to 150 ppm. External dose rates of 470-820μGy/y were calculated from volumetrically averaged sediment geochemistry for all layers and mineralogies within 30 cm of the teeth. One tooth from Layer 12.3 averaged 57±2ka assuming linear U uptake, while three from Layer 13 averaged 66±2ka, that from Layer 14.3,73±4ka, and three from Layer 21.2,87±4ka. Isochron and 230 Th/ 234 U analyses suggest that the teeth did experience linear uptake with ∼5% recent secondary U remobilization. These dates indicate that the site was inhabitted during Oxygen Isotope Stages (OIS) 5a-4, as climates were generally cooling, but beginning to fluctuate more widely. Assuming a constant sedimentation rate of 22 cm/ky, the hominid remains date to ∼74ka

The Emergence of the Pacific Meridional Overturning Circulation (PMOC) Paced by Obliquity Cycles during the Pliocene

Science.gov (United States)

Burls, N.; Fedorov, A. V.; Sigman, D. M.; Jaccard, S.; Tiedemann, R.; Haug, G. H.

2016-12-01

Deep water formation in northern high latitudes, as part of the Atlantic meridional overturning circulation (AMOC), is a critical element of modern ocean circulation and climate. For the warm Pliocene, roughly 4 to 2.8 million years ago, we present measurements and modeling evidence that deep water formation also occurred in the North Pacific, supporting another overturning cell - the Pacific meridional overturning circulation (PMOC). The evidence includes calcium carbonate accumulation in Pliocene subarctic Pacific sediments rivaling that of the modern North Atlantic, with pigment, total organic carbon, and redox-sensitive trace metal measurements supporting deep ocean ventilation as the driver of the enhanced calcium carbonate preservation. Together with high accumulation rates of biogenic opal, this implies a bi-directional communication between surface waters and the waters overlying the deep seafloor, and hence deep convection. A Pliocene-like climate simulation reproduces this deep water formation, with co-occurring Atlantic and Pacific overturning cells. The PMOC emerges as a result of the less intense hydrological cycle under Pliocene conditions characterized by a reduced meridional SST gradient. This weaker hydrological cycle leads to the erosion of the North Pacific halocline, allowing deep convection. Examining the data in more detail shows that, while the opal accumulation rate was continuously high, maxima in calcium carbonate accumulation rate were sharp and intermittent. Most likely, these maxima occurred during Northern Hemisphere summer insolation maxima when, as supported by the modeling results, mid-latitude SSTs in the Northern Hemisphere were at a maximum and the meridional SST gradient was particularly weak. These findings suggest that the climate system fluctuated between periods of strong and weak PMOC during the Pliocene. Such fluctuations appear to be a crucial part of Pliocene climate variability on orbital timescales.

Development of the Philippine Mobile Belt in northern Luzon from Eocene to Pliocene

Science.gov (United States)

Suzuki, Shigeyuki; Peña, Rolando E.; Tam, Tomas A.; Yumul, Graciano P.; Dimalanta, Carla B.; Usui, Mayumi; Ishida, Keisuke

2017-07-01

The origin of the Philippine Archipelago is characterized by the combination of the oceanic Philippine Mobile Belt (PMB) and the Palawan Continental Block (PCB). This paper is focused on the geologic evolution of the PMB in northern Luzon from Eocene to Pliocene. The study areas (northern Luzon) are situated in the central part of the PMB which is occupied by its typical components made up of a pre-Paleocene ophiolitic complex, Eocene successions, Eocene to Oligocene igneous complex and late Oligocene to Pliocene successions. Facies analysis of the middle Eocene and late Oligocene to early Pliocene successions was carried out to understand the depositional environment of their basins. Modal sandstone compositions, which reflect the basement geology of the source area, were analyzed. Major element geochemistry of sediments was considered to reconstruct the tectonic settings. The following brief history of the PMB is deduced. During the middle Eocene, the PMB was covered by mafic volcanic rocks and was a primitive island arc. In late Eocene to late Oligocene time, the intermediate igneous complex was added to the mafic PMB crust. By late Oligocene to early Miocene time, the PMB had evolved into a volcanic island arc setting. Contributions from alkalic rocks are detected from the rock fragments in the sandstones and chemical composition of the Zigzag Formation. During the middle Miocene to Pliocene, the tectonic setting of the PMB remained as a mafic volcanic island arc.

A new malaria agent in African hominids.

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Benjamin Ollomo

2009-05-01

Full Text Available Plasmodium falciparum is the major human malaria agent responsible for 200 to 300 million infections and one to three million deaths annually, mainly among African infants. The origin and evolution of this pathogen within the human lineage is still unresolved. A single species, P. reichenowi, which infects chimpanzees, is known to be a close sister lineage of P. falciparum. Here we report the discovery of a new Plasmodium species infecting Hominids. This new species has been isolated in two chimpanzees (Pan troglodytes kept as pets by villagers in Gabon (Africa. Analysis of its complete mitochondrial genome (5529 nucleotides including Cyt b, Cox I and Cox III genes reveals an older divergence of this lineage from the clade that includes P. falciparum and P. reichenowi (approximately 21+/-9 Myrs ago using Bayesian methods and considering that the divergence between P. falciparum and P. reichenowi occurred 4 to 7 million years ago as generally considered in the literature. This time frame would be congruent with the radiation of hominoids, suggesting that this Plasmodium lineage might have been present in early hominoids and that they may both have experienced a simultaneous diversification. Investigation of the nuclear genome of this new species will further the understanding of the genetic adaptations of P. falciparum to humans. The risk of transfer and emergence of this new species in humans must be now seriously considered given that it was found in two chimpanzees living in contact with humans and its close relatedness to the most virulent agent of malaria.

La mise en voix del Cantar del Mio Cid y el Códice de Vivar

OpenAIRE

Higashi, Alejandro

2007-01-01

En los últimos años, en el estudio de la mise en voix del Cantar de Mio Cid se ha privilegiado el plano musical de la interpretación. Sin descuidar esta dimensión, propongo volver sobre el plano textual y codicológico, ante la pobre evidencia preservada sobre aspectos rigurosamente musicales: las condiciones de su conservación en un códice de interés historiográfico, el conocimiento indirecto de la interpretación musical de la épica medieval, lagunas en el conocimiento de las técnicas de cant...

Entre o delito e a loucura : a enfermagem em manicômio judiciário

OpenAIRE

Dayane de Aguiar Cicolella

2014-01-01

Os manicômios judiciários são instituições responsáveis pelo cuidado dos incapazes, destinados à proteção do todo social. Possuem o duplo objetivo de custodiar e tratar pessoas com doenças mentais declaradas perigosas, podendo ser considerados uma fusão entre hospital psiquiátrico e presídio. Essa instituição utiliza técnicas e procedimentos disciplinares com objetivo de normalizar loucos criminosos para torná-los aptos ao convívio social. A pesquisa propõe estudar os dispositivos disciplinar...

Morphometric variation in Plio-Pleistocene hominid distal humeri.

Science.gov (United States)

Lague, M R; Jungers, W L

1996-11-01

The magnitude and meaning of morphological variation among Plio-Pleistocene hominid distal humeri have been recurrent points of disagreement among paleoanthropologists. Some researchers have found noteworthy differences among fossil humeri that they believe merit taxonomic separation, while others question the possibility of accurately sorting these fossils into different species and/or functional groups. Size and shape differences among fossil distal humeri are evaluated here to determine whether the magnitude and patterns of these differences can be observed within large-bodied, living hominoids. Specimens analyzed in this study have been assigned to various taxa (Australopithecus afarensis, A. africanus, A. anamensis, Paranthropus, and early Homo) and include AL 288-1m, AL 288-1s, AL 137-48a, AL 322-1, Gomboré IB 7594, TM 1517, KNM-ER 739, KNM-ER 1504, KMN-KP 271 (Kanapoi), and Stw 431. Five extant hominoid populations are sampled to provide a standard by which to consider differences found between the fossils, including two modern human groups (Native American and African American), one group of Pan troglodytes, and two subspecies of Gorilla gorilla (G.g. beringei, G.g. gorilla). All possible pairwise d values (average Euclidena distances) are calculated within each of the reference populations using an exact randomization procedure. This is done using both raw linear measurements as well as scale-free shape data created as ratios of each measurement to the geometric mean. Differences between each pair of fossil humeri are evaluated by comparing their d values to the distribution of d values found within each of the reference populations. Principal coordinate analysis and an unweighted pair group method with arithmetic averages (UPGMA) cluster analysis are utilized to further assess similarities and differences among the fossils. Finally, canonical variates analysis and discriminant analysis are employed using all hominoid samples in order to control for

Pliocene benthonic foraminifera from homogeneous and laminated marls on Crete

NARCIS (Netherlands)

Jonkers, H.A.

1984-01-01

In the Pliocene, the paleogeography of central Crete consisted of a number of basins which were filled by predominantly marly sediments. In the sedimentary sequence numerous laminated sapropelic intercalations can be observed. At a higher stratigraphic level diatomaceous laminites appear.

Antarctic and Southern Ocean influences on Late Pliocene global cooling

NARCIS (Netherlands)

McKay, R.; Naish, T.; Carter, L.; Riesselman, C.; Dunbar, R.; Sjunneskog, C.; Winter, D.; Sangiorgi, F.; Warren, C.; Pagani, M.; Schouten, S.; Willmott, V.; Levy, R.; DeConto , R.M.; Powell, R.D.

2012-01-01

The influence of Antarctica and the Southern Ocean on Late Pliocene global climate reconstructions has remained ambiguous due to a lack of well-dated Antarctic-proximal, paleoenvironmental records. Here we present ice sheet, sea-surface temperature, and sea ice reconstructions from the ANDRILL

Fault zone architecture within Miocene–Pliocene syn-rift sediments ...

Indian Academy of Sciences (India)

The present study focusses on field description of small normal fault zones in Upper Miocene–Pliocene sedimentary rocks on the northwestern side of the Red Sea, Egypt. The trend of these fault zones is mainly NW–SE. Paleostress analysis of 17 fault planes and slickenlines indicate that the tension direction is NE–SW.

Highly variable Pliocene sea surface conditions in the Norwegian Sea

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P. E. Bachem

2017-09-01

Full Text Available The Pliocene was a time of global warmth with small sporadic glaciations, which transitioned towards the larger-scale Pleistocene glacial–interglacial variability. Here, we present high-resolution records of sea surface temperature (SST and ice-rafted debris (IRD in the Norwegian Sea from 5.32 to 3.14 Ma, providing evidence that the Pliocene surface conditions of the Norwegian Sea underwent a series of transitions in response to orbital forcing and gateway changes. Average SSTs are 2 °C above the regional Holocene mean, with notable variability on millennial to orbital timescales. Both gradual changes and threshold effects are proposed for the progression of regional climate towards the Late Pliocene intensification of Northern Hemisphere glaciation. Cooling from 4.5 to 4.3 Ma may be linked to the onset of poleward flow through the Bering Strait. This cooling was further intensified by a period of cool summers due to weak obliquity forcing. A 7 °C warming of the Norwegian Sea at 4.0 Ma suggests a major increase in northward heat transport from the North Atlantic, leading to an enhanced zonal SST gradient in the Nordic Seas, which may be linked to the expansion of sea ice in the Arctic and Nordic Seas. A warm Norwegian Sea and enhanced zonal temperature gradient between 4.0 and 3.6 Ma may have been a priming factor for increased glaciation around the Nordic Seas due to enhanced evaporation and precipitation at high northern latitudes.

Diatom evidence for the onset of Pliocene cooling from AND-1B, McMurdo Sound, Antarctica

Science.gov (United States)

Riesselman, Christina; Dunbar, R. B.

2013-01-01

The late Pliocene, ~ 3.3–3.0 Ma, is the most recent interval of sustained global warmth in the geologic past. This window is the focus of climate reconstruction efforts by the U.S. Geological Survey's Pliocene Research, Interpretation, and Synoptic Mapping (PRISM) Data/Model Cooperative, and may provide a useful climate analog for the coming century. Reconstructions of past surface ocean conditions proximal to the Antarctic continent are essential to understanding the sensitivity of the cryosphere to this key interval in Earth's climate evolution. An exceptional marine sediment core collected from the southwestern Ross Sea (78° S), Antarctica, during ANDRILL's McMurdo Ice Shelf Project preserves evidence of dramatic fluctuations between grounded ice and productive, open ocean conditions during the late Pliocene, reflecting orbitally-paced glacial/interglacial cycling. In this near-shore record, diatom-rich sediments are recovered from interglacial intervals; two of these diatomites, from ~ 3.2 Ma and 3.03 Ma, are within the PRISM chronologic window. The diatom assemblages identified in PRISM-age late Pliocene diatom-rich sediments are distinct from those in mid-Pliocene and later Pliocene/Pleistocene intervals recovered from AND-1B, and comprise both extant taxa with well-constrained ecological preferences and a diverse extinct flora, some members of which are previously undescribed from Antarctic sediments. Both units are dominated by Chaetoceros resting spores, an indicator of high productivity and stratification that is present at much lower abundance in materials both older and younger than the PRISM-age sediments. Newly described species of the genus Fragilariopsis, which first appear in the AND-1B record at 3.2 Ma, are the most abundant extinct members of the PRISM-age assemblages. Other extant species with established environmental affinities, such as Fragilariopsis sublinearis, F. curta, Stellarima microtrias, and Thalassiothrix antarctica, are

NOTES ON FOSSIL CHITONS. 5. POLYPLACOPHORA FROM THE PLIOCENE OF WESTERN LIGURIA, NORTHWEST ITALY

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BRUNO DELL'ANGELO

2013-03-01

Full Text Available This study describes the chiton fauna (Mollusca, Polyplacophora from deposits of the Pliocene marine sequence of Western Liguria in northwestern Italy between Genova (Genoa and Ventimiglia. The studied fossils consist of 9,657 valves from nine sites (Bussana, Rio Sant'Antonino, Garlenda, Salea, Caranchi, Rio Torsero, Zinola, Sestri Ponente, and Borzoli; see Fig. 1 taken from the lower clayey formation named Argille di Ortovero (Ortovero Clay. From these we identified 31 species, 22 of which were already known, 5 are identified only at generic level, and four are described as new: Leptochiton josei sp. n., Ischnochiton ligusticus sp. n., Connexochiton roccai sp. n., and Lepidochitona pliocinerea sp. n. Only three species (Lepidopleurus cajetanus, Chiton corallinus and Acanthochitona fascicularis occur in all the studied sites but, even so, it is difficult to evaluate their relative prevalence. Ch. corallinus and Lepidop. cajetanus are most common, representing 46%  and 31% respectively of the total valves found. Some species found are particularly noteworthy; Lept. alveolus previously not known as a fossil, except a dubiously identified record from the Eocene/Oligocene of Washington; Lept. bedullii and I. martinelli are known only from few Pliocene localities. Four species are described as new, and this increases the number of Mediterranean Pliocene determined species known to 37. Connexochiton roccai sp. n. represent the first report of Connexochiton as a fossil. Seventeen (55% of the species found are still living in the Mediterranean Sea and 13 of these also occur in the eastern Atlantic. Only one species, Lept. alveolus, occurs as a living species in the Atlantic but is absent from the Mediterranean Sea. Five determined species are known only from Mediterranean Pliocene, and 12 are recorded for the first time from the Ligurian Pliocene. The analysis of the Ligurian samples suggests a shallow water depositional environment, possibly from

Amplified North Atlantic Warming in the Late Pliocene by Changes in Arctic Gateways

Science.gov (United States)

Otto-Bliesner, B. L.; Jahn, A.; Feng, R.; Brady, E. C.; Hu, A.; Lofverstrom, M.

2017-12-01

Reconstructions of the late Pliocene (mid-Piacenzian, 3.3 - 3.0 million years ago) sea surface temperature (SST) find much warmer conditions in the North Atlantic than modern. The much warmer SSTs, up to 8.8°C from sites with good dating and replicates from several different types of proxies, have been difficult for climate models to reproduce. Even with the slow feedbacks of a reduced Greenland ice sheet and expansion of boreal forests to the Arctic Ocean over Canada and Eurasia, models cannot warm the North Atlantic sufficiently to match the reconstructed SSTs. An enhancement of the Atlantic Meridional Overturning Circulation (AMOC) during the late Pliocene, proposed as a possible mechanism based on ocean core records of δ13C, also is not present in the model simulations. Here, we present CESM simulations using a new reconstruction of late Pliocene paleogeography that has the Bering Strait (BS) and Canadian Arctic Archipelago (CAA) Straits closed. We find that the closure of these small Arctic gateways strengthens the AMOC, by inhibiting freshwater (FW) transport from the Pacific to the Arctic Ocean and from the Arctic Ocean to the Labrador Sea, leading to warmer sea surface temperatures in the North Atlantic. The cutoff of the short export route through the CAA results in a more saline Labrador and south Greenland Sea with increased deep convection. At the same time, as all FW now leaves the Arctic east of Greenland, there is a freshening of and decreased deepwater formation in the Norwegian Sea. Overall, the AMOC strengthens. This past time period has implications for a future Earth under more responsible scenarios of emissions. Late Pliocene atmospheric carbon dioxide concentrations are estimated to have ranged between 350 and 450 ppmv and the paleogeography is relatively similar to modern. Our study indicates that the state of the Arctic gateways may influence the sensitivity of the North Atlantic climate in complex ways, and better understanding of the

Using tetraether lipids archived in North Sea Basin sediments to extract North Western European Pliocene continental air temperatures

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Dearing Crampton-Flood, E.; Peterse, F; Munsterman, D.; Sinninghe Damsté, J.S.

2018-01-01

The Pliocene is often regarded as a suitable analogue for future climate, due to an overall warmer climate (2–3 °C) coupled with atmospheric CO2 concentrations largely similar to present values (∼400 ppmv). Numerous Pliocene sea surface temperature (SST) records are available, however, little is

NW-SE Pliocene-Quaternary extension in the Apan-Acoculco region, eastern Trans-Mexican Volcanic Belt

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García-Palomo, Armando; Macías, José Luis; Jiménez, Adrián; Tolson, Gustavo; Mena, Manuel; Sánchez-Núñez, Juan Manuel; Arce, José Luis; Layer, Paul W.; Santoyo, Miguel Ángel; Lermo-Samaniego, Javier

2018-01-01

The Apan-Acoculco area is located in the eastern portion of the Mexico basin and the Trans-Mexican Volcanic Belt. The area is transected by right-stepping variably dipping NE-SW normal faults. The Apan-Tlaloc Fault System is a major discontinuity that divides the region into two contrasting areas with different structural and volcanic styles. a) The western area is characterized by a horst-graben geometry with widespread Quaternary monogenetic volcanism and scattered outcrops of Miocene and Pliocene rocks. b) The eastern area is dominated by tilted horsts with a domino-like geometry with widespread Miocene and Pliocene rocks, scattered Quaternary monogenetic volcanoes and the Acoculco Caldera. Gravity data suggest that this structural geometry continues into the Mesozoic limestones. Normal faulting was active since the Pliocene with three stages of extension. One of them, an intense dilatational event began during late Pliocene and continues nowadays, contemporaneously with the emplacement of the Apan-Tezontepec Volcanic Field and the Acoculco caldera. Statistical analysis of cone elongation, cone instability, and the kinematic analysis of faults attest for a NW50°SE ± 7° extensional regime in the Apan-Acoculco area. The activity in some portions of the Apan-Tlaloc Fault System continues today as indicated by earthquake swarms recorded in 1992 and 1996, that disrupted late Holocene paleosols, and Holocene volcanism.

Paleomagnetism and geochronology of the Pliocene-Pleistocene lavas in Iceland

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McDougall, Ian; Wensink, H.

Potassium-argon dates are reported on five basalt samples from the Pliocene-Pleistocene sequence of lavas in the Jökuldalur area, northeastern Iceland. These dates confirm the correlations previously made with the geological time scale by means of paleomagnetic stratigraphy. The R1 and N2 polarity

A revision of the Pliocene and Quaternary Lutrinae from Europe

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Willemsen, G.F.

1992-01-01

In this paper, a revision of the Pliocene and Quaternary Lutrinae from Europe is presented. Such a revision, including fossil material, has not been published since the work of Pohle (1919). Three tribes within the Lutrinae are recognized: the Lutrini, the Aonyxini and the Enhydrini. The latter

A terrestrial Pliocene-Pleistocene temperature record from North-Western Europe

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Dearing Crampton Flood, Emily; Peterse, Francien; Munsterman, Dirk; Sinninghe Damste, Jaap

2016-04-01

The Mid-Pliocene Warm Period (MPWP) (ca 3.3 to 3.0 Ma) is the most recent geological interval that serves as an appropriate analogue to our current climate for two main reasons. Firstly, atmospheric CO2 levels were similar (400 - 450 ppmv) to present day levels. Secondly, continental configurations during the Pliocene were largely similar to the present day. The MPWP is especially interesting regarding future climate predictions as global temperatures were roughly 2 - 3 °C warmer than present, indicating that current climate may not yet be in equilibrium. Reconstructions of MPWP sea surface temperatures (SSTs) indicate SSTs were warmer than present, particularly at high latitudes (ΔSST = 2 - 6 °C). However, continental temperatures for this interval remain poorly constrained due to a lack of trustworthy proxies, and scarcity of terrestrial sedimentary archives. Here we analysed branched GDGTs (brGDGTs) in a sediment core from the Netherlands to reconstruct continental mean air temperatures (MAT) in North-Western Europe during the Early Pliocene to mid-Pleistocene. BrGDGTs are membrane lipids of organisms living predominantly in soils whose relative distributions relate with the temperature and pH of the soil in which they are biosynthesized. BrGDGTs can be delivered to coastal marine sediments by fluvially transported soil material. Due to the coastal position of the sample site, land-sea climate correlations can be studied by analysing temperature-sensitive marine biomarkers, i.e. alkenones and long chain diols, in the same sediment, and subsequently applying the Uk37', TEX86, and long chain diol index (LDI) paleothermometers. The obtained MAT record can be divided into four main events: two small 'glacial' events, the MPWP, and the onset of Northern Hemisphere glaciation marking the onset of the Pleistocene, the latter being characterized by unstable and fluctuating temperatures. The glacial periods have been tentatively assigned according to the De Schepper

The Transylvanian Basin (Romania) and its relation to the Carpathian fold and thrust belt: Insights in gravitational salt tectonics

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Krezsek, Csaba [SNGN ROMGAZ, 4 Unirii 551025 Medias (Romania); Bally, Albert W. [Department of Geology and Geophysics, University of Rice, 6100 South Main Street, Houston, TX 77005-1892 (United States)

2006-05-15

Interpretation of regional seismic profiles, stratigraphic and sedimentologic data improved insights in the evolution of the Transylvanian Basin. The basin evolution was coeval with the post-Mid-Cretaceous to recent deformation of the Carpathian Mts. Four tectonostratigraphic megasequences are differentiated: Upper Cretaceous (rift), Paleogene (sag), Lower Miocene (flexural basin) and Middle to Upper Miocene (backarc sequence dominated by gravitational tectonics). The Mid-Miocene continental collision in the Eastern Carpathians is associated with the rising Carpathians. This uplift enhanced the differential load, which, together with the high heat flow induced by Late Miocene to Pliocene arc volcanism, triggered large-scale Mio-Pliocene gravity spreading of the salt overburden. This 'mega-slide' comprises three structural domains, as follows: extensional weld (upslope), contractional folds (central) and contractional toe thrust (downslope). The diapirs in the east indicate a pre-shortening reactive/passive growth stage. The central folds are mostly the result of late shortening. Basement involved thrusting uplifted the toe thrust domain by the Late Pliocene. The Late Neogene to recent Carpathians uplift, backarc volcanism and gravity spreading are largely coeval. (author)

Diet and environment of a mid-Pliocene fauna from southwestern Himalaya: Paleo-elevation implications

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Wang, Yang; Xu, Yingfeng; Khawaja, Sofia; Passey, Benjamin H.; Zhang, Chunfu; Wang, Xiaoming; Li, Qiang; Tseng, Zhijie J.; Takeuchi, Gary T.; Deng, Tao; Xie, Guangpu

2013-08-01

A mid-Pliocene fauna (4.2-3.1 Ma) was recently uncovered in the Zanda (Zhada) Basin in the southwestern Himalaya, at an elevation of about 4200 m above sea level. These fossil materials provide a unique window for examining the linkage among tectonic, climatic and biotic changes. Here we report the results from isotopic analyses of this fauna and of modern herbivores and waters as well as paleo-temperature estimates from the Zanda Basin. The δ13C values of enamel samples from modern wild Tibetan asses, and domesticated horses, cows and goats in the area are -9.4±1.8‰, which indicate a diet comprising predominantly of C3 plants and are consistent with the current dominance of C3 vegetation in the region. The enamel-δ13C values of the fossil horses, rhinos, deer, and bovids are -9.6±0.8‰, indicating that these ancient mammals, like modern herbivores in the area, also fed primarily on C3 vegetation and lived in an environment dominated by C3 plants. The lack of significant C4 plants in the basin suggests that the area had reached high elevations (>2.5 km) by at least the mid-Pliocene. Taking into account the changes in the δ13C of atmospheric CO2 in the past, the enamel-δ13C values suggest that the average modern-equivalent δ13C value of C3 vegetation in the Zanda Basin in the mid-Pliocene was ∼1-2‰ lower than that of the C3 biomass in the basin today. This would imply a reduction in annual precipitation by about 200-400 mm in the area since then (assuming that the modern C3 δ13C-precipitation relationship applied to the past). Consistent with this inference from the δ13C data, the enamel-δ18O data show a significant shift to higher values after the mid-Pliocene, which also suggests a shift in climate to much drier conditions after ∼4-3 Ma. Paleo-temperature estimates derived from a fossil bone-based oxygen isotope temperature proxy as well as the carbonate clumped isotope thermometer for the mid-Pliocene Zanda Basin are higher than the present

African climate and vegetation at the roots of humankind during the Pliocene

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Contoux, Camille; Ramstein, Gilles; Banks, Will; Sepulchre, Pierre; Schuster, Mathieu; Zhang, Zhongshi

2017-04-01

This study is devoted to the intricate links between climate, vegetation and hominin population distribution during Pliocene, during which peculiar combinations of climate and vegetation conditions have favored the development of hominin species. The aridification of North Africa from the Late Oligocene to the Tortonian has been recently linked to the Tethys shrinkage and associated changes in monsoon patterns. Since the Tortonian the response to orbital forcing has drastically increased accompanied by the onset of the Sahara desert [Zhang et al , Nature 2014] . Therefore, the context of the emergence and development of hominins is marked by a succession of wet and dry periods driven by orbital forcing factors. We focus here on the Pliocene period during which fossils have been discovered West and East of the African Rift (in the Chad basin and Rift Valley respectively). In order to better understand the climate and vegetation relationships during this period allowing populations to live both West and East of the Rift, we simulated the climate of the Pliocene for different orbital configurations with the coupled model IPSL-CM5A (OAGCM). We then use these simulated climates to carry out an equilibrium vegetation model, BIOME4, for 4 different orbital configurations with high eccentricity. We found that australopithecines occur in areas were primary productivity and precipitation are low, suggesting they were adapted to semi-arid environments.

La mise en voix del Cantar del Mio Cid y el Códice de Vivar

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Alejandro Higashi

2007-11-01

Full Text Available In the last years, the musical performance has taken an important place in the study of the mise en voix of the Cantar de Mio Cid. Although this perspective is laudable in many ways, I propose to take care on the textual and codicological plane, because many of the musical traces are lost for distinct reasons: the condition of the copy, finished according to the historiographical patterns of the medieval scriptorium; the indirect knowledge of the medieval epic music; the gaps in the understanding of how medieval cantillation was performed during public workship, in the laic or clerical life; the influence (or not of the medieval chant dialects (especially, mozarabic and eugenian chants, etc.

Truncorotalia crassaformis from its type locality: Comparison with Caribbean plankton and Pliocene relatives

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Scott, George H.; Ingle, James C.; McCane, Brendan; Powell, Charles L.; Thunell, Robert C.

2015-01-01

Truncorotalia crassaformis has been identified in Pliocene-Holocene assemblages globally but there has been little analysis of specimens from its type locality at Lomita Quarry, California. This has led to confusion about some diagnostic criteria, particularly the presence of a peripheral keel. To better understand variation specimens are studied from the type locality (Pleistocene, c. 400–600 ka), supplemented by material from a plankton trap in Cariaco Basin and from ODP 925, Ceara Rise (Pliocene, c. 4.3 Ma). The damaged holotype has a weak topographic ridge (keel) at the periphery of early chambers of the outer whorl. Several well-preserved specimens have a keel on all chambers of the whorl. Encrustation obscures the periphery on some and masks shell shape. Several outliers in a morphometric analysis of axial shape have distinctive discoidal outlines but ventroconical (cone-like) forms are common. Lomita Marl was deposited on a sheltered, shallow shelf in Chron 1. Foraminifera reworked from the unconformably underlying Repetto Siltstone are present. Specimens resembling the holotype are very rare and often damaged. Morphological disparity is high. It is unlikely that an autochthonous population was sampled. The weak peripheral keel present on some living specimens from Cariaco Basin is built incrementally by a thin featureless calcitic veneer deposited between the morphogenesis of each chamber. The process progressively obscures pores in the primary wall. Its earliest stages have been misidentified as a poreless zone. Ventroconical form is weak in the Ceara Rise Pliocene specimens and is distinguishable from the Cariaco sample. There is only a veneer at the periphery. Although the study does not provide a population-based diagnosis of T. crassaformis it indicates that the name should not be applied to early Pliocene forms.

A revised geological range (Late Pliocene) for foraminifer taxon Bolliella adamsi Banner et Blow, 1959

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Reddy, A. Nallapa; Nagendra, R.

2017-12-01

The foraminifer taxon Bolliella adamsi Banner et Blow, 1959 is found to co-occur with index planktic foraminifer taxa of the Late Pliocene (Zone N21) in a core of 2.60 m at 1300 m water depth off Tuticorin, Bay of Bengal. This taxon has been previously known as a Holocene taxon of the Indo-Pacific province. This study significantly revises the known stratigraphic range of B. adamsi from the Late Pliocene (uppermost part of Zone N21) to the Holocene in the Bay of Bengal area.

Influence of the Eastern California Shear Zone on deposition of the Mio-Pliocene Bouse Formation: Insights from the Cibola area, Arizona

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Dorsey, Rebecca J.; O'Connell, Brennan; Homan, Mindy B.; Bennett, Scott E. K.

2017-01-01

The Eastern California Shear Zone (ECSZ) is a wide zone of late Cenozoic strike-slip faults and related diffuse deformation that currently accommodates ~20–25% of relative Pacific–North America plate motion in the lower Colorado River region (Fig. 1A; Dokka and Travis, 1990; Miller et al., 2001; Guest et al., 2007; Mahan et al., 2009). The ECSZ is kinematically linked southward to dextral faults in the northern Gulf of California (Bennett et al., 2016a), and it may have initiated ca. 8 Ma when major strike-slip faults developed in the northern Gulf and Salton Trough region (Bennett et al., 2016b; Darin et al., 2016; Woodburne, 2017). Thus deformation related to the ECSZ occurred in the lower Colorado River region during deposition of the Bouse Formation, which is commonly bracketed between 6.0 and 4.8 Ma (House et al., 2008; Sarna-Wojcicki et al., 2011; Spencer et al., 2013) and may be as old as 6–7 Ma in the south (McDougall and Miranda Martínez, 2014, 2016). Post-4.5 Ma broad sagging is recognized along the lower Colorado River (Howard et al., 2015), but the possibility that faults of the ECSZ influenced local to regional subsidence patterns during deposition of the Bouse Formation has received little attention to date (e.g., Homan, 2014; O’Connell et al., 2016). The Bouse Formation is a widespread sequence of late Miocene to early Pliocene deposits exposed discontinuously along the lower Colorado River corridor (Fig. 1A). In the southern Blythe basin it consists of three regionally correlative members: (1) Basal Carbonate, consisting of supratidal and intertidal mud-flat marls, intertidal and shallow subtidal bioclastic grainstone and conglomerate, and subtidal marl; (2) Siliciclastic member, consisting of Colorado River-derived green claystone, red mudstone and siltstone, and cross-bedded river channel sandstone; and (3) Upper Bioclastic member fossiliferous sandy calcarenite, coarse pebbly grainstone, and calcareous-matrix conglomerate (Homan, 2014

A strengthened East Asian Summer Monsoon during Pliocene warmth: Evidence from 'red clay' sediments at Pianguan, northern China

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Yang, Shiling; Ding, Zhongli; Feng, Shaohua; Jiang, Wenying; Huang, Xiaofang; Guo, Licheng

2018-04-01

The Pliocene epoch (5.3-2.6 Ma) is the most recent geological interval in which atmospheric CO2 levels were similar to those of the present day (∼400 ppmv). This epoch is therefore considered to be the best ancient analog for predicting a future anthropogenic greenhouse world. In order to determine the response of the East Asian Summer Monsoon (EASM) rainbelt during Pliocene warmth, a 71.9 m-thick aeolian 'red clay' sequence at Pianguan was investigated. Rock magnetic experiments suggest that magnetite of pseudo-single domain size is the dominant remanence carrier in the 'red clay' sequence. Magnetostratigraphic data, constrained by lithostratigraphy, show that the polarity zones of the 'red clay' section correlate with those between subchrons C2An.2r and C3An.2n of the geomagnetic polarity time scale (GPTS), yielding an age range of 6.9-2.9 Ma. The 'red clay' deposits exhibit enhanced weathering intensity over two time intervals, namely 5.23-4.3 Ma and 3.7-2.9 Ma, as evidenced by their well-developed pedogenic characteristics, as well as their high free to total Fe2O3 ratios and high redness (a∗) values, which in turn indicate an increased summer monsoon intensity during most of the Pliocene. Furthermore, the pedogenic characteristics of the well-weathered Pliocene soils were compared with those of paleosol unit S5 (one of the best-developed soil units found in Pleistocene loess) from the Yulin, Luochuan and Lantian sections, which constitute a north-south transect across the Chinese Loess Plateau (CLP). The Pliocene soils at Pianguan show a pedogenic development similar to the S5 (∼0.5 Ma) at Luochuan in the central Plateau, which is located some 3.7° latitude south of Pianguan, but this development is much stronger than that observed at Yulin in the north, and weaker than that seen at Lantian in the south. This may imply a more northerly penetration (∼400 km) of the monsoon rainbelt during Pliocene warmth compared with the Pleistocene interglacial

Shark-Cetacean trophic interaction, Duinefontein, Koeberg, (5 Ma, South Africa

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Romala Govender

2015-11-01

Full Text Available This study forms part of a larger project to reconstruct the Mio-Pliocene marine palaeoenvironment along South Africa’s west coast. It documents the shark–cetacean trophic interaction during the Zanclean (5 Ma at Duinefontein (Koeberg. The damage described on the fragmentary cetacean bones was compared with similar damage observed on fossils from Langebaanweg, a Mio-Pliocene site on the west coast of South Africa, and data present in the literature. This comparison showed that the damage was the result of shark bites. The state of preservation makes it difficult to determine if the shark bite marks were the cause of death or as a result of scavenging. The presence of the bite marks on the bone would, however, indicate some degree of skeletonisation. Bite marks on some cranial fragments would suggest that the cetacean’s body was in an inverted position typical of a floating carcass. The preservation of the material suggests that the bones were exposed to wave action resulting in their fragmentation as well as abrasion, polishing and rolling. It also suggests that the cetacean skeletons were exposed for a long time prior to burial. The morphology of the bites suggests that the damage was inflicted by sharks with serrated and unserrated teeth. Shark teeth collected from the deposit include megalodon (Carcharodon megalodon, white (Carcharodon carcharias as well as mako (Isurus sp. and Cosmopolitodus hastalis sharks, making these sharks the most likely predators/scavengers.

The endemic mollusks reveal history of the long-lived Pliocene Lake Slavonia in NW Croatia

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Mandic, Oleg; Kurečić, Tomislav; Neubauer, Thomas A.; Harzhauser, Mathias

2015-04-01

The present investigation deals with the fossil mollusk record of the long-lived Pliocene Lake Slavonia settled in the southern Pannonian Basin. The samples originate from Vukomeričke gorice, a low hill-range situated north of the Kupa River in the area between the towns of Zagreb, Sisak and Karlovac in NW Croatia. Representing the SW margin of the Lake Slavonia the freshwater deposits alternate there with the alluvial series, providing altogether about 400-m-thick, Pliocene continental succession, known in literature by informal name Paludina beds (acc. to a junior synonym of Viviparus). The endemic fauna of the Lake Slavonia became particularly well-known in the late 19th century after Melchior Neumayr demonstrated that the gradual evolutionary change of the mollusk phenotypes toward more complex morphology represents a function of adaptation to environmental change in the paleolake. Even Charles Darwin commented that result as by far the best case which I have ever met with, showing the direct influence of the conditions of life on the organization. The deposition in the Lake Slavonia (~4.5 to ~1.8 Ma) coincides with the Pliocene Climate Optimum (PCO), but captures also the transition into the Pleistocene climate marked by the initial Ice Age pulse at 2.59 Ma. The increase of polar temperatures resulted during PCO in a significant melting of the ice caps leading to a global sea level rise tentatively getting up to 25 m higher than today. Coincidence of the climate and geodynamic settings in southeastern Europe provided conditions supporting extended settlement of lacustrine environments including Lake Slavonia, Lake Kosovo, Lake Transylvania and Lake Dacia, all characterized by explosive adaptive radiations of viviparid snails. In particular, the latter adaptive radiations resulted in the regional phylostratigraphy of Lake Slavonia Viviparus species enabling excellent stratigraphic control for the investigated deposits. Hence, based on this evidence, the

A comparative study of large-scale atmospheric circulation in the context of a future scenario (RCP4.5 and past warmth (mid-Pliocene

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Y. Sun

2013-07-01

Full Text Available The mid-Pliocene warm period (~ 3.3–3.0 Ma is often considered as the last sustained warm period with close enough geographic configurations compared to the present one associated with atmospheric CO2 concentration (405 ± 50 ppm higher than the modern level. For this reason, this period is often considered as a potential analogue for the future climate warming, with the important advantage that for mid-Pliocene many marine and continental data are available. To investigate this issue, we selected the RCP4.5 scenario, one of the current available future projections, to compare the pattern of tropical atmospheric response with the past warm mid-Pliocene climate. We use three Atmosphere-Ocean General Circulation Model (AOGCM simulations (RCP4.5 scenario, mid-Pliocene and present-day simulation carried out with the IPSL-CM5A model and investigate atmospheric tropical dynamics through Hadley and Walker cell responses to warmer conditions, considering that the analysis can provide some assessment of how these circulations will change in the future. Our results show that there is a damping of the Hadley cell intensity in the northern tropics and an increase in both subtropics. Moreover, northern and southern Hadley cells expand poleward. The response of the Hadley cells is stronger for the RCP4.5 scenario than for the mid-Pliocene, but in very good agreement with the fact that the atmospheric CO2 concentration is higher in the future scenario than in the mid-Pliocene (543 versus 405 ppm. Concerning the response of the Walker cell, we show that despite very large similarities, there are also some differences. Common features to both scenarios are: weakening of the ascending branch, leading to a suppression of the precipitation over the western tropical Pacific. The response of the Walker cell is stronger in the RCP4.5 scenario than in the mid-Pliocene but also depicts some major differences, as an eastward shift of its rising branch in the future

Sea surface temperatures from the southern Benguela region from the Pliocene and Pleistocene: tracking Agulhas Current input into the SE Atlantic

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Petrick, B. F.; McClymont, E.; Felder, S.; Lloyd, J. M.; Leng, M. J.

2011-12-01

The Pliocene and-Pleistocene epochs provide a way to understand the effect of past climate changes on key ocean currents. Here, we show results from ODP Site1087 (31.28'S, 15.19'E, 1374m water depth) to investigate changes in ocean circulation over the period of the mid-Pliocene warm period 3.0-3.5 Ma and compare these to the time of the 100 kyr Pleistocene glacial cycles. ODP 1087 is located in the South-eastern Atlantic Ocean, outside of the Benguela upwelling region; reconstructing the temperature history of the site will therefore provide an important data set from a part of the ocean that has few orbital-scale and continuous Pliocene temperature reconstructions. ODP 1087 can be used to investigate the history of the heat and salt transfer to the Atlantic Ocean from the Indian Ocean via the Agulhas Retroflection, which plays an important part in the global thermohaline circulation (Lutjeharms, 2007). Climate models and reconstructions for the most recent glacial-interglacial cycles have shown that changes to the strength of the heat transfer may cause major climatic changes and may play a role in transitions from glacial to interglacial events (Knorr & Lohmann, 2003). It is unknown how this transfer reacted to generally warmer global temperatures during the mid-Pliocene. Because the mid-Pliocene is seen as a model for future climate change it might provide a model for ocean circulations in a warmer world. Our approach is to apply several organic geochemistry proxies and foraminiferal analyses to reconstruct the history of ODP 1087. The UK37' index records differences in the unsaturated bonds in the C37 alkenones to reconstruct sea surface temperatures (Brassell et al., 1986). We present SSTs generated for the mid-Pliocene Warm period with a resolution of 4000 years. We compare this data to the time of the 100 kyr glacial cycles during the late Pleistocene. Even though ODP 1087 is located outside the Benguela upwelling system, it has lower Pliocene temperatures

Late Pliocene History of Mediterranean Outflow Water in the Gulf of Cadiz (IODP Expedition 339, Site U1389)

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Grunert, P.; Balestra, B.; Flores, J. A.; Sierro, F. J.; García Gallardo, Á.; Piller, W. E.; Aubry, M. P.

2014-12-01

The opening and closure of ocean gateways play an important role amongst climate forcing mechanisms: surface and deep-water circulation are altered, and hence global heat transport. An important component of North Atlantic circulation patterns is the warm and saline Mediterranean Outflow Water (MOW) that enters the North Atlantic via the Gibraltar Strait. Its onset and early history after the opening of the Gibraltar Strait at 5.3 Ma are poorly constrained and its impact on oceanography and climate in the Pliocene are largely unexplored. Current research efforts in the scope of projects funded by the Austrian Science Fund (FWF-P25831-N29) and the Max Kade Foundation aim to improve our knowledge about this early phase of MOW. Research focuses on Sites U1387C (upper Miocene-lower Pliocene; ~5.8-3.8 Myrs) and U1389E (middle-upper Pliocene; ~3.7-2.8) drilled during IODP Expedition 339 in the northern Gulf of Cádiz close to the source area of MOW. At IODP Site U1389E, a 280m-thick sequence of upper Pliocene contourites is studied to reconstruct MOW behavior and potential paleoceanographic and paleoclimatic feedback mechanisms during the Mid-Pliocene Thermal Optimum. Currently, a reliable age model is developed for the studied interval based on bio-, chemo-, and cyclostratigraphy. Several biostratigraphic datums have been identified from analyses of calcareous nannoplankton and planktic foraminifera which indicate a depositional age between 3.65 Ma and 2.87 Ma. In some intervals of the record a further refinement of the age model at the millenial scale is complicated by poor recovery. However, preliminary results from high-resolution geochemical analyses of the bulk sediment (TOC, CaCO3 and S) and shells of the planktic foraminifer Globigerinoides ruber (δ18O, δ13C) reveal distinct cyclic patterns in several well recovered intervals. Based on an average sedimentation rate of ~25cm/ka, these cycles most likely reflect precessional forcing. Current paleoceanographic

Technical note: Late Pliocene age control and composite depths at ODP Site 982, revisited

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N. Khélifi

2012-01-01

Full Text Available Ocean Drilling Program (ODP Site 982 provided a key sediment section at Rockall Plateau for reconstructing northeast Atlantic paleoceanography and monitoring benthic δ¹⁸O stratigraphy over the late Pliocene to Quaternary onset of major Northern Hemisphere glaciation. A renewed hole-specific inspection of magnetostratigraphic reversals and the addition of epibenthic δ¹⁸O records for short Pliocene sections in holes 982A, B, and C, crossing core breaks in the δ¹⁸O record published for Hole 982B, now imply a major revision of composite core depths. After tuning to the orbitally tuned reference record LR04, the new composite δ¹⁸O record results in a hiatus, where the Kaena magnetic subchron might have been lost, and in a significant age reduction for all proxy records by 130 to 20 ky over the time span 3.2–2.7 million years ago (Ma. Our study demonstrates the general significance of reliable composite-depth scales and δ¹⁸O stratigraphies in ODP sediment records for generating ocean-wide correlations in paleoceanography. The new concept of age control makes the late Pliocene trends in SST (sea surface temperature and atmospheric pCO₂ at Site 982 more consistent with various paleoclimate trends published from elsewhere in the North Atlantic.

A new species of great ape from the late Miocene epoch in Ethiopia.

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Suwa, Gen; Kono, Reiko T; Katoh, Shigehiro; Asfaw, Berhane; Beyene, Yonas

2007-08-23

With the discovery of Ardipithecus, Orrorin and Sahelanthropus, our knowledge of hominid evolution before the emergence of Pliocene species of Australopithecus has significantly increased, extending the hominid fossil record back to at least 6 million years (Myr) ago. However, because of the dearth of fossil hominoid remains in sub-Saharan Africa spanning the period 12-7 Myr ago, nothing is known of the actual timing and mode of divergence of the African ape and hominid lineages. Most genomic-based studies suggest a late divergence date-5-6 Myr ago and 6-8 Myr ago for the human-chimp and human-gorilla splits, respectively-and some palaeontological and molecular analyses hypothesize a Eurasian origin of the African ape and hominid clade. We report here the discovery and recognition of a new species of great ape, Chororapithecus abyssinicus, from the 10-10.5-Myr-old deposits of the Chorora Formation at the southern margin of the Afar rift. To the best of our knowledge, these are the first fossils of a large-bodied Miocene ape from the African continent north of Kenya. They exhibit a gorilla-sized dentition that combines distinct shearing crests with thick enamel on its 'functional' side cusps. Visualization of the enamel-dentine junction by micro-computed tomography reveals shearing crest features that partly resemble the modern gorilla condition. These features represent genetically based structural modifications probably associated with an initial adaptation to a comparatively fibrous diet. The relatively flat cuspal enamel-dentine junction and thick enamel, however, suggest a concurrent adaptation to hard and/or abrasive food items. The combined evidence suggests that Chororapithecus may be a basal member of the gorilla clade, and that the latter exhibited some amount of adaptive and phyletic diversity at around 10-11 Myr ago.

Regional and global climate for the mid-Pliocene using the University of Toronto version of CCSM4 and PlioMIP2 boundary conditions

Directory of Open Access Journals (Sweden)

D. Chandan

2017-07-01

Full Text Available The Pliocene Model Intercomparison Project Phase 2 (PlioMIP2 is an international collaboration to simulate the climate of the mid-Pliocene interglacial, corresponding to marine isotope stage KM5c (3.205 Mya, using a wide selection of climate models with the objective of understanding the nature of the warming that is known to have occurred during the broader mid-Pliocene warm period. PlioMIP2 builds on the successes of PlioMIP by shifting the focus to a specific interglacial and using a revised set of geographic and orbital boundary conditions. In this paper, we present the details of the mid-Pliocene simulations that we have performed with a slightly modified version of the Community Climate System Model version 4 (CCSM4 and the enhanced variant of the PlioMIP2 boundary conditions. We discuss the simulated climatology through comparisons to our control simulations and to proxy reconstructions of the mid-Pliocene climate. With the new boundary conditions, the University of Toronto version of the CCSM4 model simulates a mid-Pliocene that is more than twice as warm as that with the boundary conditions used for PlioMIP Phase 1. The warming is more enhanced near the high latitudes, which is where most of the changes to the PlioMIP2 boundary conditions have been made. The elevated warming in the high latitudes leads to a better match between the simulated climatology and proxy-based reconstructions than possible with the previous version of the boundary conditions.

Dinoflagellate cysts and the paleoenvironment of Late-Pliocene early-pleistocene deposits of Brittany, Northwest France

Science.gov (United States)

Morzadec-Kerfourn, Marie Thérèse

The marine Pliocene facies of the Redon clay is widely distributed in the western part of Brittany. the decrease in the abundance of Tertiary pollen towards the top of the deposits, coupled with the increase of pollen of boreal forest taxa and the development of Ericaceae and Poaceae indicates a Late-Pliocene age. The occurrence of the transgression maximum is recorded in calcareous beds which contain the highest concentration of microforaminiferal linings and dinoflagellate cysts. Hystrichokolpoma rigaudae and Melitasphaeridium choanophorum, along with Achomosphaera andalousiensis and Operculodinium israelianum make up these aseemblages. The presence of dinoflagellate cyst assemblages with estuarine and neritic affinities but with an occasional oceanic form, indicates sedimentation in coastal waters with a neritic influence. The paleotopography exerts a control on the altitudinal distribution of the Redon clays in the western part of Brittany to the west of the Rennes Basin. The Pliocene-Pleistocene dinoflagelate cyst assemblages of southern England and northwestern france show a remarkable degree of homogeneity in their composition, chiefly expressed in the apparent contradictory association of A. andalousensis and O. israelianum that suggest sedimentation in an unusual type of environment which arose in the context of climatic change and sea-level variations at that time.

Impact of a permanent El Niño (El Padre) and Indian Ocean Dipole in warm Pliocene climates

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Shukla, Sonali P.; Chandler, Mark A.; Jonas, Jeff; Sohl, Linda E.; Mankoff, Ken; Dowsett, Harry J.

2009-01-01

 Pliocene sea surface temperature data, as well as terrestrial precipitation and temperature proxies, indicate warmer than modern conditions in the eastern equatorial Pacific and imply permanent El Niño–like conditions with impacts similar to those of the 1997/1998 El Niño event. Here we use a general circulation model to examine the global-scale effects that result from imposing warm tropical sea surface temperature (SST) anomalies in both modern and Pliocene simulations. Observed SSTs from the 1997/1998 El Niño event were used for the anomalies and incorporate Pacific warming as well as a prominent Indian Ocean Dipole event. Both the permanent El Niño (also called El Padre) and Indian Ocean Dipole (IOD) conditions are necessary to reproduce temperature and precipitation patterns consistent with the global distribution of Pliocene proxy data. These patterns may result from the poleward propagation of planetary waves from the strong convection centers associated with the El Niño and IOD.

Probing the active site of MIO-dependent 2,3-aminomutases, key catalysts in the biosynthesis of beta-amino acids incorporated in secondary metabolites

Science.gov (United States)

Bruner, Steven D.; Cooke, Heather

2012-01-01

The tyrosine aminomutase SgTAM produces (S)-β-tyrosine from l-tyrosine in the biosynthesis of the enediyne antitumor antibiotic C-1027. This conversion is promoted by the methylideneimidazole-5-one (MIO) prosthetic group. MIO was first identified in the homologous family of ammonia lyases, which deaminate aromatic amino acids to form α,β-unsaturated carboxylates. Studies of substrate specificity have been described for lyases but there have been no reports in altering the substrate specificity of aminomutases. Furthermore, it remains unclear as to what structural properties are responsible for catalyzing the presumed readdition of the amino group into the α,β-unsaturated intermediates to form β-amino acids. Attempts to elucidate specificity and mechanistic determinants of SgTAM have also proved to be difficult as it is recalcitrant to perturbations to the active site via mutagenesis. An X-ray co-crystal structure of the SgTAM mutant of the catalytic base with l-tyrosine verified important substrate binding residues as well as the enzymatic base. Further mutagenesis revealed that removal of these crucial interactions renders the enzyme inactive. Proposed structural determinants for mutase activity probed via mutagenesis, time-point assays and X-ray crystallography revealed a complicated role for these residues in maintaining key quaternary structure properties that aid in catalysis. PMID:20577998

Diet and environment of a mid-Pliocene fauna in the Zanda Basin (western Himalaya): Paleo-elevation implications

Science.gov (United States)

Wang, Y.; Xu, Y.; Khawaja, S. N.; Wang, X.; Passey, B. H.; Zhang, C.; Li, Q.; Tseng, Z. J.; Takeuchi, G.; Deng, T.; Xie, G.

2011-12-01

A mid-Pliocene fauna (3.1-4.0 Ma) was recently discovered in the Zanda Basin in western Himalaya, at an elevation of about 4200 m above sea level. These fossil materials provide a unique window for examining the linkage among tectonic, climatic and biotic changes. Here we report the initial results from isotopic analyses of this fauna and of modern herbivores in the Zanda Basin. The δ13C values of enamel samples from modern wild Tibetan ass, horse, cow and goat from the Zanda Basin are -9.1±2.1%, which indicate a diet comprising predominantly of C3 plants and are consistent with the current dominance of C3 vegetation in the area. The enamel-δ13C values of the fossil horse, rhino, deer, and bovid are -9.6±0.8%, indicating that these ancient mammals, like modern herbivores in the area, fed primarily on C3 vegetation and lived in an environment dominated by C3 plants. The enamel-δ18O values of mid-Pliocene obligate drinkers (i.e., horse and rhino) are lower than those of their modern counterpart, most likely indicating a shift in climate to much drier conditions after ~3-4 Ma. Preliminary paleo-temperature estimates derived from a fossil-based temperature proxy as well as the "clumped isotope" thermometer for the mid-Pliocene Zanda Basin, although somewhat equivocal, are close to the present-day mean annual temperature in the area, suggesting that the paleo-elevation of the Zanda Basin in the mid-Pliocene was similar to its present-day elevation.

Diet of Australopithecus afarensis from the Pliocene Hadar Formation, Ethiopia

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Wynn, Jonathan G.; Sponheimer, Matt; Kimbel, William H.; Alemseged, Zeresenay; Reed, Kaye; Bedaso, Zelalem K.; Wilson, Jessica N.

2013-06-01

The enhanced dietary flexibility of early hominins to include consumption of C4/crassulacean acid metabolism (CAM) foods (i.e., foods derived from grasses, sedges, and succulents common in tropical savannas and deserts) likely represents a significant ecological and behavioral distinction from both extant great apes and the last common ancestor that we shared with great apes. Here, we use stable carbon isotopic data from 20 samples of Australopithecus afarensis from Hadar and Dikika, Ethiopia (>3.4-2.9 Ma) to show that this species consumed a diet with significant C4/CAM foods, differing from its putative ancestor Au. anamensis. Furthermore, there is no temporal trend in the amount of C4/CAM food consumption over the age of the samples analyzed, and the amount of C4/CAM food intake was highly variable, even within a single narrow stratigraphic interval. As such, Au. afarensis was a key participant in the C4/CAM dietary expansion by early australopiths of the middle Pliocene. The middle Pliocene expansion of the eastern African australopith diet to include savanna-based foods represents a shift to use of plant food resources that were already abundant in hominin environments for at least 1 million y and sets the stage for dietary differentiation and niche specialization by subsequent hominin taxa.

Environmental significance of Upper Miocene phosphorites at hominid sites in the Lukeino Formation (Tugen Hills, Kenya)

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Dericquebourg, Perrine; Person, Alain; Ségalen, Loïc; Pickford, Martin; Senut, Brigitte; Fagel, Nathalie

2015-08-01

The Lukeino Formation contains an important sedimentary and fossiliferous record of the late Miocene (6.09-5.68 Ma), which has in particular yielded the fossil remains of the oldest East African bipedal hominid called Orrorin tugenensis. This fluvio-lacustrine sedimentary succession crops out in the Kenyan part of the East African Rift. It is mainly composed of clay to sandy clay deposits intercalated with volcanic ash horizons, and localized layers of carbonates and diatomites. A detailed sedimentological and mineralogical study of the Lukeino Formation was conducted to throw light on the environmental conditions in which the hominids lived. Several centimetric, relatively continuous and indurated phosphatic horizons, of sedimentary origin, were identified at two sites (Sunbarua and Kapcheberek). Mineralogical (XRD) and geochemical analyses as well as observations by SEM, which was coupled with an energy dispersive spectroscopy (EDS) microprobe, indicate that the autochthonous phosphate layers are composed of a micritic matrix of francolite (38-93%), with incorporation of silicates in variable proportions from one layer to another. The phosphate matrix contains very well preserved and abundant diatom frustules in the basal phosphate layer. These diatoms are identified as Aulacoseira granulata, implying a pH of 7.8-8.2 for freshwaters of the Palaeolake Lukeino. Calcitic tubular structures, linked to a possible bacterial origin, are also observed locally. Phosphate layers occur abruptly within a thick clay-sandy series, associated with an intense runoff phase during the deposition of this interval of the Lukeino Formation. The massive and cyclic input of phosphorus to the lake promoted productivity to the stage where it caused a diatom bloom. The establishment of several phosphate horizons testifies to successive phases of eutrophication of Palaeolake Lukeino. The diatom cells provided some of the organic matter, which was decomposed by bacterial activity at the

Estimates of Eastern Equatorial Pacific Sea Surface Temperatures During the Pliocene From Carbonate 'Clumped Isotope' Thermometry

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Thiagarajan, N.; Tripati, A.; Eiler, J.

2007-12-01

The early Pliocene (5 to 3 Ma) was an interval in Earth history that was globally warmer than the present; thus, study of the details of Pliocene climate can provide insights into the dynamics of warm climates. There are two competing models of the temperature structure of the tropical Pacific upper-ocean during the early Pliocene: the dynamical 'ocean thermostat' model [1,2] and the 'El Padre' (or permanent 'El Nino') model [3], each of which predict zonal temperature gradients and mean conditions in the Eastern Equatorial Pacific (EEP), and which differ markedly from one another in these predictions. The dynamical 'ocean thermostat' model predicts an increased temperature contrast between the Western Equatorial Pacific (WEP) and EEP, enhanced thermocline tilt and intensified upwelling under warmer conditions. In contrast, the 'El Padre' model postulates a collapse of the zonal temperature gradient, reduced thermocline tilt and a reduction in upwelling and/or warmer temperatures of upwelled waters. Existing reconstructions of tropical temperatures produce WEP sea surface temperatures which agree with each other, but yield very different results in the EEP [4,5]. We have reconstructed EEP sea surface temperatures at Ocean Drilling Program (ODP) Site 847 using a few samples spanning key intervals of the last 6 million years using carbonate clumped isotope thermometer [6,7,8]. This technique is based on the temperature dependence of the abundances of 13C-18O bonds in carbonate minerals. Initial measurements of planktonic foraminifera and coccoliths from ODP Site 847 indicate cool EEP sea surface temperatures, supporting models of Pliocene climate that have enhanced zonal temperature gradients, relative to modern. Analyses of Globigerinoides sacculifer (with sac) from sediments indicate calcification temperatures of 20.3°C ± 0.1°C and seawater δ18O values of -0.8‰ ± 0.1‰ from ~6.1 to 5.1 million years ago. Measurements of a mixed coccolith assemblage from the

Variations in Mediterranean-Atlantic exchange across the late Pliocene climate transition

Science.gov (United States)

García-Gallardo, Ángela; Grunert, Patrick; Piller, Werner E.

2018-03-01

Mediterranean-Atlantic exchange through the Strait of Gibraltar plays a significant role in the global ocean-climate dynamics in two ways. On one side, the injection of the saline and warm Mediterranean Outflow Water (MOW) contributes to North Atlantic deep-water formation. In return, the Atlantic inflow is considered a sink of less saline water for the North Atlantic Ocean. However, while the history of MOW is the focus of numerous studies, the Pliocene Atlantic inflow has received little attention so far. The present study provides an assessment of the Mediterranean-Atlantic exchange with a focus on the Atlantic inflow strength and its response to regional and global climate from 3.33 to 2.60 Ma. This time interval comprises the mid-Pliocene warm period (MPWP; 3.29-2.97 Ma) and the onset of the Northern Hemisphere glaciation (NHG). For this purpose, gradients in surface δ18O records of the planktonic foraminifer Globigerinoides ruber between the Integrated Ocean Drilling Program (IODP) Hole U1389E (Gulf of Cádiz) and Ocean Drilling Program (ODP) Hole 978A (Alboran Sea) have been evaluated. Interglacial stages and warm glacials of the MPWP revealed steep and reversed (relative to the present) W-E δ18O gradients suggesting a weakening of Mediterranean-Atlantic exchange likely caused by high levels of relative humidity in the Mediterranean region. In contrast, periods of stronger inflow are indicated by flat δ18O gradients due to more intense arid conditions during the severe glacial Marine Isotope Stage (MIS) M2 and the initiation of NHG (MIS G22, G14, G6-104). Intensified Mediterranean-Atlantic exchange in cold periods is linked to the occurrence of ice-rafted debris (IRD) at low latitudes and a weakening of the Atlantic Meridional Overturning Circulation (AMOC). Our results thus suggest the development of a negative feedback between AMOC and exchange rates at the Strait of Gibraltar in the latest Pliocene as it has been proposed for the late Quaternary.

Acerca del rol de Pedro Bermúdez en el Cantar de Mio Cid: Un acercamiento a su figura épica

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Érica Janín

2007-11-01

Full Text Available This work makes an attempt on getting close to the literary figure of Pedro Bermúdez in the Cantar de Mio Cid that allows it to characterize him as a peculiar hero; and proposes that Pedro represents a type of hero which is different to the model the Cantar means to coin, perhaps more primitive and alternative to the cidian paradigm, thus the virtues and values of the tradition of the most arcaic epic songs are not eliminated but displaced to a hero that seconds the protagonist, complementing him at the same time.

Earlier (late Pliocene) first appearance of the Caribbean reef-building coral Acropora palmata: Stratigraphic and evolutionary implications

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McNeill, Donald F.; Budd, Ann F.; Borne, Pamela F.

1997-10-01

An integrated stratigraphic study of reefal deposits on the Caribbean side of the Isthmus of Panama (Limon, Costa Rica) has discovered a significantly earlier first appearance of the major reef-building coral Acropora palmata. A. palmata is here reported from the early late Pliocene, constrained in age to within the Gauss chron (ca. 3.6 2.6 Ma). This coral was previously thought to have originated in the earliest Pleistocene and has subsequently been used as a Quaternary marker throughout the Caribbean and the Bahamas. An earlier appearance in the southern Caribbean implies a diachronous first appearance datum relative to the northern Caribbean. This older age also places A. palmata well within the transition phase of a Pliocene (4 1 Ma) faunal turnover that was marked by widespread extinction and origination of Caribbean coral species. An early late Pliocene origination is coincident with formation of the Isthmus, climate reorganization, and frequent sea-level changes associated with onset of Northern Hemisphere glaciations. The rapid growth and accumulation rates that characterize A. palmata may therefore be adaptive to these fluctuating environmental conditions, enabling its success during the subsequent Pleistocene glacial cycles.

Ocean circulation in the southern Benguela region from the Pliocene to the Pleistocene: tracking Agulhas leakage into the SE Atlantic

Science.gov (United States)

Petrick, Benjamin; McClymont, Erin; Felder, Sojna; Leng, Melanie

2013-04-01

The transition from the warmth of the middle Pliocene to the large amplitude, 100 kyr glacial-interglacial cycles of the late Pleistocene provides a way to understand the forcings and impacts of regional and global climate change. Here, we investigate changes in ocean circulation over the period from 3.5 Ma to present using a marine sediment core, ODP Site 1087 (31o28'S, 15o19'E, 1374m water depth). ODP 1087 is located in the South-east Atlantic Ocean, outside the Benguela upwelling region. Its location allows investigation of the history of the heat and salt transfer to the Atlantic Ocean from the Indian Ocean ("Agulhas leakage"), which plays an important part in the global thermohaline circulation. It is not known how this transfer reacted to generally warmer global temperatures during the mid-Pliocene, nor to the transition to a globally cooler climate in the early Pleistocene. Our approach is to apply several organic geochemistry proxies and foraminiferal analyses to reconstruct the history of ODP 1087. These include the U37K' index to reconstruct sea surface temperatures, pigment analysis for understanding productivity changes, and foraminifera assemblage analysis to detect the presence of different water masses at the site. We have identified changes in SSTs and biological productivity that we argue to reflect shifts in the position of the Benguela upwelling cells, and a changing influence of Agulhas leakage. Our new data reveal a different organization in the Southeast Atlantic. It shows that during the Pliocene ODP 1087 was dominated by Benguela upwelling which had shifted south. We find no evidence for Agulhas leakage during the mid Pliocene, which could mean that Agulhas Leakage was severely reduced during the mid Pliocene. The implications of these results for understanding Plio-Pleistocene climate changes will be explored here.

Pliocene-Quaternary history of Futuna island, south Vanuatu, southwest Pacific

International Nuclear Information System (INIS)

Neef, G.; McCulloch, M.T.

2001-01-01

Uranium-series ages from thermal ionisation mass spectrometry are reported here for the raised coral reefs of Futuna Island, which lies adjacent to the eastern margin of the backarc Futuna Trough in south Vanuatu, southwest Pacific. U-series ages from coral from the lowest raised reef indicate that its upper part is most likely to be ca 210 ka, whereas the most elevated raised reef has a likely age of ca 520 ka (range 600-440 ka). The inferred Pliocene-Quaternary history for Futuna Island and the adjacent Futuna Trough is: (i) formation of the Pliocene - Early Quaternary basaltic-andesite cone in a southeast part of the Vanuatu Island Arc; (ii) inception of the Futuna Trough (adjacent to the west margin of Futuna Island) since 1.8Ma; (iii) subsequent uplift of the volcanic cone above sea-level caused ∼ 500 m of its upper part to be removed by marine erosion; (iv) the island then subsided and at least 160 m of limestone was deposited on the truncated cone; and (v) during the period 520 ka to ca 210 ka seven fringing reefs formed at the margin of the cone as the island was uplifted. Since ca 210 ka Futuna further subsided and, as a result, the post ca 210 ka history of the island is obscure. Copyright (2001) Geological Society of Australia

The PRISM (Pliocene Palaeoclimate) reconstruction: Time for a paradigm shift

Science.gov (United States)

Dowsett, Harry J.; Robinson, Marci M.; Stoll, Danielle K.; Foley, Kevin M.; Johnson, Andrew L. A.; Williams, Mark; Riesselman, Christina

2013-01-01

Global palaeoclimate reconstructions have been invaluable to our understanding of the causes and effects of climate change, but single-temperature representations of the oceanic mixed layer for data–model comparisons are outdated, and the time for a paradigm shift in marine palaeoclimate reconstruction is overdue. The new paradigm in marine palaeoclimate reconstruction stems the loss of valuable climate information and instead presents a holistic and nuanced interpretation of multi-dimensional oceanographic processes and responses. A wealth of environmental information is hidden within the US Geological Survey's Pliocene Research,Interpretation and Synoptic Mapping (PRISM) marine palaeoclimate reconstruction, and we introduce here a plan to incorporate all valuable climate data into the next generation of PRISM products. Beyond the global approach and focus, we plan to incorporate regional climate dynamics with emphasis on processes, integrating multiple environmental proxies wherever available in order to better characterize the mixed layer, and developing a finer time slice within the Mid-Piacenzian Age of the Pliocene, complemented by underused proxies that offer snapshots into environmental conditions. The result will be a proxy-rich, temporally nested, process-oriented approach in a digital format - a relational database with geographic information system capabilities comprising a three-dimensional grid representing the surface layer, with a plethora of data in each cell.

Extension of the astronomically calibrated (polarity) time scale to the Miocene/Pliocene boundary

NARCIS (Netherlands)

Hilgen, F.J.

1991-01-01

The early Pleistocene to late Pliocene astronormcally calibrated time scale of Shackleton et al. [1] and Hllgen [2] is extended to the Mlocene/Pllocene boundary This is done by correlating the detailed record of CaCO 3 cycles in the Trubl and the lower part of the overlying Narbone Formation

Palaeobotanical data for climate change during the late Miocene - early Pliocene in Western Bulgaria

International Nuclear Information System (INIS)

Hristova, Viktoria; Ivanov, Dimiter; Bozukov, Vladimir

2015-01-01

The Coexistence Approach (CA) analysis was applied to plant macro- and microfossils from the Late Miocene to Early Pliocene sites in western Bulgaria to obtain quantitative climate data and reconstruct climate dynamics. Calculated new values for the Sofia macro flora confirmed a warm-temperate and humid climate with mean annual temperature (MAT) between 12–170C, mean temperature of the warmest month (WMT) 23.6–280C, mean temperature of the coldest month (CMT) 0–50C and mean annual precipitation (MAP) 843–1179 mm. This is consistent with the climatic parameters obtained from the microflora – MAT 13.6–16, WMT 23.6–27.9, CMT 3.7–6 and MAP 803–1308mm. All presented data are in good accordance with other regional palaeoclimate reconstructions from Bulgarian and Europaean floras. Key words: Late Miocene–Early Pliocene, palaeoclimate, Sofia Basin

Mid-Pliocene global climate simulation with MRI-CGCM2.3: set-up and initial results of PlioMIP Experiments 1 and 2

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Y. Kamae

2012-05-01

Full Text Available The mid-Pliocene (3.3 to 3.0 million yr ago, a globally warm period before the Quaternary, is recently attracting attention as a new target for paleoclimate modelling and data-model synthesis. This paper reports set-ups and results of experiments proposed in Pliocene Model Intercomparison Project (PlioMIP using a global climate model, MRI-CGCM2.3. We conducted pre-industrial and mid-Pliocene runs by using the coupled atmosphere-ocean general circulation model (AOGCM and its atmospheric component (AGCM for the PlioMIP Experiments 2 and 1, respectively. In addition, we conducted two types of integrations in AOGCM simulation, with and without flux adjustments on sea surface. General characteristics of differences in the simulated mid-Pliocene climate relative to the pre-industrial in the three integrations are compared. In addition, patterns of predicted mid-Pliocene biomes resulting from the three climate simulations are compared in this study. Generally, difference of simulated surface climate between AGCM and AOGCM is larger than that between the two AOGCM runs, with and without flux adjustments. The simulated climate shows different pattern between AGCM and AOGCM particularly over low latitude oceans, subtropical land regions and high latitude oceans. The AOGCM simulations do not reproduce wetter environment in the subtropics relative to the present-day, which is suggested by terrestrial proxy data. The differences between the two types of AOGCM runs are small over the land, but evident over the ocean particularly in the North Atlantic and polar regions.

A revision of the Pliocene and Quaternary Lutrinae from Europe

OpenAIRE

Willemsen, G.F.

1992-01-01

In this paper, a revision of the Pliocene and Quaternary Lutrinae from Europe is presented. Such a revision, including fossil material, has not been published since the work of Pohle (1919). Three tribes within the Lutrinae are recognized: the Lutrini, the Aonyxini and the Enhydrini. The latter comprises both Enhydra and the Enhydriodon group. The genus Nesolutra, consisting of three insular species, is not retained. Two are included in Lutra and for N. ichnusae a new genus, Sardolutra, is pr...

Pliocene to early Middle Pleistocene ursine bears in Europe: a taxonomic overview

Czech Academy of Sciences Publication Activity Database

Wagner, Jan

2010-01-01

Roč. 179, - (2010), s. 197-215 ISSN 1802-6842 R&D Projects: GA ČR GA205/09/0184; GA AV ČR IAA300130701 Institutional research plan: CEZ:AV0Z30130516 Keywords : Ursus * taxonomy * Pliocene * Pleistocene Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/publikace-download.php?name=File1&dir=archiv&table=tabPublikaceArchiv&id=2796

The impact of dynamic topography on the bedrock elevation and volume of the Pliocene Antarctic Ice Sheet

Science.gov (United States)

Austermann, Jacqueline; Pollard, David; Mitrovica, Jerry X.; Moucha, Robert; Forte, Alessandro M.; DeConto, Robert M.

2015-04-01

Reconstructions of the Antarctic ice sheet over long timescales (i.e. Myrs) require estimates of bedrock elevation through time. Ice sheet models have accounted, with varying levels of sophistication, for changes in the bedrock elevation due to glacial isostatic adjustment (GIA), but they have neglected other processes that may perturb topography. One notable example is dynamic topography, the deflection of the solid surface of the Earth due to convective flow within the mantle. Numerically predicted changes in dynamic topography have been used to correct paleo shorelines for this departure from eustasy, but the effect of such changes on ice sheet stability is unknown. In this study we use numerical predictions of time-varying dynamic topography to reconstruct bedrock elevation below the Antarctic ice sheet during the mid Pliocene warm period (~3 Ma). Moreover, we couple this reconstruction to a three-dimensional ice sheet model to explore the impact of dynamic topography on the evolution of the Antarctic ice sheet since the Pliocene. Our modeling indicates significant uplift in the area of the Transantarctic Mountains (TAM) and the adjacent Wilkes basin. This predicted uplift, which is at the lower end of geological inferences of uplift of the TAM, implies a lower elevation of the basin in the Pliocene. Relative to simulations that do not include dynamic topography, the lower elevation leads to a smaller Antarctic Ice Sheet volume and a more significant retreat of the grounding line in the Wilkes basin, both of which are consistent with offshore sediment core data. We conclude that reconstructions of the Antarctic Ice Sheet during the mid-Pliocene warm period should be based on bedrock elevation models that include the impact of both GIA and dynamic topography.

Hydrogen peroxide modulates energy metabolism and oxidative stress in cultures of permanent human Müller cells MIO-M1.

Science.gov (United States)

Peters, Sven; Griebsch, Max; Klemm, Matthias; Haueisen, Jens; Hammer, Martin

2017-09-01

In this study the influence of hydrogen peroxide (H 2 O 2 ) on the redox state, NADH protein binding, and mitochondrial membrane potential in Müller cells is investigated. Cultures of permanent human Müller cells MIO-M1 were exposed to H 2 O 2 in 75 µM and 150 µM concentration for two hours. Fluorescence emission spectra and lifetimes were measured by two-photon microscopy (excitation wavelength: 740 nm) at the mitochondria which were identified in the microscopic images by their fluorescence properties (spectra and intensity). Two hours of H 2 O 2 exposure did not impair viability of MIO-M1 cells in culture. Whereas the ratio of flavine- to NADH fluorescence intensity did not change under either H 2 O 2 concentration, the mean lifetime was significantly different between controls, not exposed to H 2 O 2 , and the 150 µM H 2 O 2 exposure (972 ± 63 ps vs. 1152 ± 64 ps, p = 0.014). One hour after cessation of the H 2 O 2 exposure, the value retuned to that of the control (983 ± 36 ps). A hyperpolarization of the mitochondrial membrane under 150 µM H 2 O 2 was found. These findings suggest a shift form free to protein-bound NADH in mitochondria as well as a hyperpolarization of their inner membrane which could be related to an impairment of Müller cell function despite their preserved viability. Exposure of human Müller cells to hydrogen peroxide for two hours results in a reversible change of protein binding of mitochondrial NADH upon unchanged redox ratio. The mitochondrial membrane potential is increased during exposure. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sedimentation and paleoecology of Pliocene lagoonal-shallow marine deposits on the island of Rhodes (Greece)

NARCIS (Netherlands)

Broekman, J.A.

1974-01-01

A detailed analysis of the depositional and paleontological characteristics of a section of the Pliocene Kritika Formation on the island of Rhodos is presented. The environmental significance of sedimentary structures, the paleoecology of benthonic Foraminifera, and the sequentional

Pliocene bats (Chiroptera) from Kanapoi, Turkana Basin, Kenya.

Science.gov (United States)

Gunnell, Gregg F; Manthi, Fredrick K

2018-04-05

Fossil bats from the Pliocene of Africa are extremely rare, especially in East Africa where meager records have been reported only from two localities in the Omo River Basin Shungura Formation and from a scattering of localities in the Afar Depression, both in Ethiopia. Here we report on a diverse assemblage of bats from Kanapoi in the Turkana Basin that date to approximately 4.19 million years ago. The Kanapoi bat community consists of four different species of fruit bats including a new genus and two new species as well as five species of echolocating bats, the most common of which are two new species of the molossid genus Mops. Additionally, among the echolocating bats, a new species of the emballonurid Saccolaimus is documented at Kanapoi along with an additional Saccolaimus species and a potentially new species of the nycterid Nycteris. Compared to other East African Pliocene bat assemblages, the Kanapoi bat community is unique in preserving molossids and curiously lacks any evidence of cave dwelling bats like rhinolophids or hipposiderids, which are both common at other East African sites. The bats making up the Kanapoi community all typically roost in trees, with some preferring deeper forests and larger trees (molossids), while the others (pteropodids, nycterids and emballonurids) roost in trees near open areas. Living fruit bats that are related to Kanapoi species typically forage for fruits along the margins of forests and in open savannah. The echolocating forms from Kanapoi consist of groups that aerially hawk for insects in open areas between patches of forest and along water courses. The habitats preferred by living relatives of the Kanapoi bats are in agreement with those constructed for Kanapoi based on other lines of evidence. Copyright © 2018. Published by Elsevier Ltd.

Magma evolution in the Pliocene Pleistocene succession of Kos, South Aegean arc (Greece)

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Pe-Piper, Georgia; Moulton, Ben

2008-11-01

This study investigates the petrogenesis of Pliocene-Quaternary andesites, dacites and rhyolites of the island of Kos. These volcanic rocks differ from other volcanic centres in the South Aegean arc in the narrow range of Pliocene volcanic products, the abundance of high-silica rhyolite, the lower ɛNd for a given Sr isotope composition, and greater depth to the subducting slab. Pliocene and early Pleistocene dacite stocks and rhyolite domes are succeeded by younger tuffs, notably the 0.16 Ma Kos Plateau Tuff derived from a super-eruption of an andesite stratocone now subsided beneath the sea south of Kos. Volcanic products in tuffs have been sampled from lithic clasts. Andesite, dacite and rhyolite all have ɛNd ˜+ 1.5 to -1.5 and 86Sr/ 87Sr ˜ 0.7042; this unusual composition is argued to be the result of subduction of sediments derived from the River Nile. All rock types show structures indicative of widespread magma mixing, including complexly zoned plagioclase, clinopyroxene and amphibole containing glass inclusions of trachyte and rhyolite compositions. The observed rocks result from fractionation and mixing of three principal magma types: (a) calc-alkaline high-Al basalt that fractionated to andesite at the base of crust; (b) partially melted metabasaltic amphibolite underplated at the base of crust, that fractionated to produce high-SiO 2 rhyolite; and (c) a minor component of trachytic magma from partial melting of enriched subcontinental lithospheric mantle. The complexly zoned phenocrysts with glass inclusions provide specific evidence for mixing of these three components. Specifically, it was the emplacement of the andesite into a voluminous rhyolite magma in a mid-crustal magma chamber that led to the explosive Kos Plateau Tuff super-eruption.

Late Pliocene diversity and distribution of Drynaria (Polypodiaceae in western Yunnan explained by forest vegetation and humid climates

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Yong-Jiang Huang

2016-08-01

Full Text Available The palaeodiversity of flowering plants in Yunnan has been extensively interpreted from both a molecular and fossil perspective. However, for cryptogamic plants such as ferns, the palaeodiversity remains poorly known. In this study, we describe a new ferny fossil taxon, Drynaria lanpingensis sp. nov. Huang, Su et Zhou (Polypodiaceae, from the late Pliocene of northwestern Yunnan based on fragmentary frond and pinna with in situ spores. The frond is pinnatifid and the pinnae are entirely margined. The sori are arranged in one row on each side of the primary vein. The spores have a semicircular to bean-shaped equatorial view and a tuberculate surface. Taken together with previously described fossils, there are now representatives of three known fossil taxa of Drynaria from the late Pliocene of western Yunnan. These finds suggest that Drynaria diversity was considerable in the region at that time. As Drynaria is a shade-tolerant plant, growing preferably in wet conditions in the understory of forests, its extensive existence may indicate forest vegetation and humid climates in western Yunnan during the late Pliocene. This is in line with results from floristic investigations and palaeoclimatic reconstructions based on fossil floras.

The evolution of the equatorial thermocline and the early Pliocene El Padre mean state

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Ford, Heather L.; Ravelo, A. Christina; Dekens, Petra S.; LaRiviere, Jonathan P.; Wara, Michael W.

2015-06-01

The tropical Pacific thermocline strength, depth, and tilt are critical to tropical mean state and variability. During the early Pliocene (~3.5 to 4.5 Ma), the Eastern Equatorial Pacific (EEP) thermocline was deeper and the cold tongue was warmer than today, which resulted in a mean state with a reduced zonal sea surface temperature gradient or El Padre. However, it is unclear whether the deep thermocline was a local feature of the EEP or a basin-wide condition with global implications. Our measurements of Mg/Ca of Globorotalia tumida in a western equatorial Pacific site indicate Pliocene subsurface temperatures warmer than today; thus, El Padre included a basin-wide thermocline that was relatively warm, deep, and weakly tilted. At ~4 Ma, thermocline steepening was coupled to cooling of the cold tongue. Since ~4 Ma, the basin-wide thermocline cooled/shoaled gradually, with implications for thermocline feedbacks in tropical dynamics and the interpretation of TEX86-derived temperatures.

Lower Pliocene Fast and Repetitive Vegetation Changes In Southwestern Romania As A Response To Milankovitch Cycles

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Popescu, S.-M.; Suc, J.-P.; Loutre, M. F.

High-resolution pollen analyses on the lignite-clay Lupoaia section (from 4.9 to 4.3 Ma) in southwestern Romania provide an accurate record of the Lower Pliocene veg- etation changes in the Danube paleodelta environment close to the Carpathians. Many major fluctuations concern thermophilous trees vs. altitudinal trees (chiefly in agree- ment with lignite-clay alternations) and have been referred to changes in temperature. Thanks to a reliable magnetostratigraphic calibration of the section, such changes are to be linked to eccentricity cycles, that provides a more precise chronologic control to the section (Popescu, in press). In addition, regular secondary fluctuations occur which oppose swamp trees (such as most of the Taxodiaceae) to marsh herbs (such as Cyperaceae). They evoke the present-day landscape of the Mississippi delta where swamp forests (constituted by Taxodium distichum mainly) are in competition with herbaceous marshes (made of Cyperaceae such as Mariscus jamaicensis in addition to some Cyrillaceae and Myrica). The latest require significantly more water than the swamps (Roberts, 1986). These plant environments cause two kinds of lignite deposition that have been also identified in the Lupoaia section (Ticleanu and Dia- conita, 1997). According to the chronologic frame previously defined, it is possible to evidence a precession forcing for these alternations. Minima in precession probably caused increasing rainfall over the region and expansion of marshes. So, it is sug- gested that during Lower Pliocene the West Asian monsoon influenced climate of the northeastern Mediterranean region. References. Popescu, S.-M., in press. Repetitive changes in Lower Pliocene vegetation revealed by high-resolution pollen analysis: revised cyclostratigraphy of Southwest- ern Romania. Rev. Palaeobot. Palynol. Roberts, H.H., 1986. Selected depositional en- vironments of the Mississippi River deltaic plain. Geol. Sc. America Centennial Field Guide-Southeastern Section

Eocene to mid-Pliocene landscape evolution in Scandinavia inferred from offshore sediment volumes and pre-glacial topography using inverse modelling

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Pedersen, Vivi K.; Braun, Jean; Huismans, Ritske S.

2018-02-01

The origin of high topography in Scandinavia is highly debated, both in terms of its age and the underlying mechanism for its formation. Traditionally, the current high topography is assumed to have formed by several Cenozoic (mainly Neogene) phases of surface uplift and dissection of an old peneplain surface. These same surface uplift events are suggested to explain the increased deposition observed in adjacent offshore basins on the Norwegian shelf and in the North Sea. However, more recently it has been suggested that erosion and isostatic rock uplift of existing topography may also explain the recent evolution of topography in Scandinavia. For this latter view, the increased sedimentation towards the present is assumed to be a consequence of a climate related increase in erosion. In this study we explore whether inverse modelling of landscape evolution can give new insight into Eocene to mid-Pliocene (54-4 Ma) landscape evolution in the Scandinavian region. We do this by combining a highly efficient forward-in-time landscape evolution model (FastScape) with an optimization scheme suitable for non-linear inverse problems (the neighbourhood algorithm - NA). To limit our approach to the fluvial regime, we exclude the most recent mid-Pliocene-Quaternary time period where glacial erosion processes are expected to dominate landscape evolution. The "goodness" of our landscape evolution models is evaluated using i) sediment fluxes based on decompacted offshore sediment volumes and ii) maximum pre-glacial topography from a mid-Pliocene landscape, reconstructed using geophysical relief and offshore sediment volumes from the mid-Pliocene-Quaternary. We find several tested scenarios consistent with the offshore sediment record and the maximum elevation for our reconstructed pre-glacial (mid-Pliocene) landscape reconstruction, including: I) substantial initial topography ( 2 km) at 54 Ma and no induced tectonic rock uplift, II) the combination of some initial topography ( 1

Late Pliocene Quaternary tectonics in the frontal part of the SE Carpathians: Insights from tectonic geomorphology

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Necea, Diana; Fielitz, W.; Matenco, L.

2005-12-01

The Romanian East Carpathians display large-scale heterogeneities along the mountain belt, unusual foredeep geometries, significant post-collisional and neotectonic activity, and major variations in topography, mostly developed in the aftermath of late Miocene (Sarmatian; ˜11 Ma) subduction/underthrusting and continental collision between the East European/Scythian/Moesian foreland and the inner Carpathians Tisza-Dacia unit. In particular, the SE corner of the arcuate orogenic belt represents the place of still active large-scale differential vertical movements between the uplifting mountain chain and the subsiding Focşani foredeep basin. In this key area, we have analysed the configuration of the present day landforms and the drainage patterns in order to quantify the amplitude, timing and kinematics of these post-collisional late Pliocene-Quaternary vertical movements. A river network is incising in the upstream a high topography consisting of the external Carpathians nappes and the Pliocene-Lower Pleistocene sediments of the foreland. Further eastwards in the downstream, this network is cross-cutting a low topography consisting of the Middle Pleistocene-Holocene sediments of the foreland. Geological observations and well-preserved geomorphic features demonstrate a complex succession of geological structures. The late Pliocene-Holocene tectonic evolution is generally characterised by coeval uplift in the mountain chain and subsidence in the foreland. At a more detailed scale, these vertical movements took place in pulses of accelerated motion, with laterally variable amplitude both in space and in time. After a first late Pliocene uplifting period, subsidence took place during the Earliest Pleistocene resulting in a basal Quaternary unconformity. This was followed by two, quantifiable periods of increased uplift, which affected the studied area at the transition between the Carpathians orogen and the Focşani foreland basin in the late Early Pleistocene and the

Simulations of the Mid-Pliocene Warm Period Using Two Versions of the NASA-GISS ModelE2-R Coupled Model

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Chandler, M. A.; Sohl, L. E.; Jonas, J. A.; Dowsett, H. J.; Kelley, M.

2013-01-01

The mid-Pliocene Warm Period (mPWP) bears many similarities to aspects of future global warming as projected by the Intergovernmental Panel on Climate Change (IPCC, 2007). Both marine and terrestrial data point to high-latitude temperature amplification, including large decreases in sea ice and land ice, as well as expansion of warmer climate biomes into higher latitudes. Here we present our most recent simulations of the mid-Pliocene climate using the CMIP5 version of the NASAGISS Earth System Model (ModelE2-R). We describe the substantial impact associated with a recent correction made in the implementation of the Gent-McWilliams ocean mixing scheme (GM), which has a large effect on the simulation of ocean surface temperatures, particularly in the North Atlantic Ocean. The effect of this correction on the Pliocene climate results would not have been easily determined from examining its impact on the preindustrial runs alone, a useful demonstration of how the consequences of code improvements as seen in modern climate control runs do not necessarily portend the impacts in extreme climates.Both the GM-corrected and GM-uncorrected simulations were contributed to the Pliocene Model Intercomparison Project (PlioMIP) Experiment 2. Many findings presented here corroborate results from other PlioMIP multi-model ensemble papers, but we also emphasize features in the ModelE2-R simulations that are unlike the ensemble means. The corrected version yields results that more closely resemble the ocean core data as well as the PRISM3D reconstructions of the mid-Pliocene, especially the dramatic warming in the North Atlantic and Greenland-Iceland-Norwegian Sea, which in the new simulation appears to be far more realistic than previously found with older versions of the GISS model. Our belief is that continued development of key physical routines in the atmospheric model, along with higher resolution and recent corrections to mixing parameterisations in the ocean model, have led

Constraints on sea level during the Pliocene: Records from the deep Pacific Ocean

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Woodard, S. C.; Rosenthal, Y.; Miller, K. G.; Wright, J. D.; Chiu, B. K.

2013-12-01

To reconstruct sea level during the transition from peak late Pliocene warmth (~3.15 Ma) to the onset of N. Hemisphere glaciation (~2.75 Ma), we generated high resolution stable isotope (δ18O, δ13C) and trace metal (Mg/Ca) records using benthic foraminifera, Uvigerina sp., from northwest Pacific ODP Site 1208 (3350 m water depth). During the peak late Pliocene warmth Mg/Ca-derived temperature records indicate deep Pacific interglacial temperatures were not significantly warmer (+0.6 ×0.8°C) than modern and glacial temperatures were near freezing similar to the LGM. In contrast, the deep N. Atlantic (Site 607) was apparently ~3°C warmer than the modern during both Pliocene glacial and interglacial periods (Sosdian and Rosenthal, 2009), based on the Mg/Ca of P. wuellerstorfi, which may be influenced by carbonate ion effect (Elderfield et al., 2009 and refs therein). δ18O records indicate a significant long-term increase in benthic δ18O in both the N. Atlantic and N. Pacific, although the rate of increase (Δδ18O) in the N. Atlantic is approximately 3x that of the N. Pacific (Site 1208), based on least squares regressions of all glacial-interglacial data. The discrepancy in the Δδ18O between the two basins is explained by Mg/Ca-derived temperature records. Results from Site 1208 show that the deep Pacific experienced no long-term cooling over the period 3.15-2.7 Ma when the deep N. Atlantic cooled by ~2.5°C on average. The relatively stable Pacific deep-water record provides the more reliable reconstructions of sea-level changes. From 3.15-2.7 Ma, Pacific δ18O data records an average increase of ~0.19× 0.08 per mil implying a sea level drop of 19 m × 8 m. After correcting the N. Atlantic record for temperature, we find the long term δ18O change from 3.15-2.7 Ma is ~0.23×0.1 per mil which equates to a peak of 23 m × 10 m. Our estimates are further corroborated by foraminiferal calcite δ18O recorded during Pliocene peak interglacials KM3 and G17. The �

The response of calcifying plankton to climate change in the Pliocene

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C. V. Davis

2013-09-01

Full Text Available As a result of anthropogenic pCO2 increases, future oceans are growing warmer and lower in pH and oxygen, conditions that are likely to impact planktic communities. Past intervals of elevated and changing pCO2 and temperatures can offer a glimpse into the response of marine calcifying plankton to changes in surface oceans under conditions similar to those projected for the future. Here we present new records of planktic foraminiferal and coccolith calcification (weight and size from Deep Sea Drilling Project Site 607 (mid-North Atlantic and Ocean Drilling Program Site 999 (Caribbean Sea from the Pliocene, the last time that pCO2 was similar to today, and extending through a global cooling event into the intensification of Northern Hemisphere glaciation (3.3 to 2.6 million years ago. Test weights of both surface-dwelling Foraminifera Globigerina bulloides and thermocline-dwelling Foraminifera Globorotalia puncticulata vary with a potential link to regional temperature variation in the North Atlantic, whereas in the tropics Globigerinoides ruber test weight remains stable. In contrast, reticulofenestrid coccoliths show a narrowing size range and a decline in the largest lith diameters over this interval. Our results suggest no major changes in plankton calcite production during the high pCO2 Pliocene or during the transition into an icehouse world.

The impact of dynamic topography change on Antarctic Ice Sheet stability during the Mid-Pliocene Warm Period

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Austermann, J.; Pollard, D.; Mitrovica, J. X.; Moucha, R.; Forte, A. M.; Deconto, R. M.; Rowley, D. B.; Raymo, M. E.

2015-12-01

The mid-Pliocene warm period (MPWP; ~ 3Ma), characterized by globally elevated temperatures (2-3º C) and carbon dioxide levels of ~400ppm, is commonly used as a testing ground for investigating ice sheet stability in a slightly warmer world. The central, unanswered question in this regard is the extent of East Antarctic melting during the MPWP. Here we assess the potential role of dynamic topography on this issue. Model reconstructions of the evolution of the Antarctic ice sheet during the ice age require an estimate of bedrock elevation through time. Ice sheet models account for changes in bedrock elevation due to glacial isostatic adjustment (GIA), often using simplified models of the GIA process, but they generally do not consider other processes that may perturb subglacial topography. One such notable process is dynamic topography, i.e. the deflection of the solid surface of the Earth due to convective flow and buoyancy variations within the mantle and lithosphere. Paleo-shorelines of Pliocene age reflect the influence of dynamic topography, but the impact of these bedrock elevation changes on ice sheet stability in the Antarctic region is unknown. In this study we use viscous flow simulations of mantle dynamics to predict changes in dynamic topography and reconstruct bedrock elevations below the Antarctic Ice Sheet since the MPWP. We furthermore couple this reconstruction to a three-dimensional ice sheet model in order to explore the impact of dynamic topography on the extent of the Antarctic Ice Sheet during the Pliocene. Our modeling indicates that uplift occurred in the area of the Transantarctic Mountains and the adjacent Wilkes Basin. This predicted uplift, which is consistent with geological inferences of uplift in the Transantarctic Mountains, implies a significantly (~100-200 m) lower elevation of the Wilkes Basin in the Pliocene. This lower elevation leads to ~400 km of additional retreat of the grounding line in this region relative to simulations

Modelling the mid-Pliocene Warm Period climate with the IPSL coupled model and its atmospheric component LMDZ5A

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C. Contoux

2012-06-01

Full Text Available This paper describes the experimental design and model results of the climate simulations of the mid-Pliocene Warm Period (mPWP, ca. 3.3–3 Ma using the Institut Pierre Simon Laplace model (IPSLCM5A, in the framework of the Pliocene Model Intercomparison Project (PlioMIP. We use the IPSL atmosphere ocean general circulation model (AOGCM, and its atmospheric component alone (AGCM, to simulate the climate of the mPWP. Boundary conditions such as sea surface temperatures (SSTs, topography, ice-sheet extent and vegetation are derived from the ones imposed by the Pliocene Model Intercomparison Project (PlioMIP, described in Haywood et al. (2010, 2011. We first describe the IPSL model main features, and then give a full description of the boundary conditions used for atmospheric model and coupled model experiments. The climatic outputs of the mPWP simulations are detailed and compared to the corresponding control simulations. The simulated warming relative to the control simulation is 1.94 °C in the atmospheric and 2.07 °C in the coupled model experiments. In both experiments, warming is larger at high latitudes. Mechanisms governing the simulated precipitation patterns are different in the coupled model than in the atmospheric model alone, because of the reduced gradients in imposed SSTs, which impacts the Hadley and Walker circulations. In addition, a sensitivity test to the change of land-sea mask in the atmospheric model, representing a sea-level change from present-day to 25 m higher during the mid-Pliocene, is described. We find that surface temperature differences can be large (several degrees Celsius but are restricted to the areas that were changed from ocean to land or vice versa. In terms of precipitation, impact on polar regions is minor although the change in land-sea mask is significant in these areas.

Hydrogeological geochemical and isotopic study of the coastal aquifer of Sousse Eastern, Tunisia

International Nuclear Information System (INIS)

Ben-Hamouda, M. F.; Carreira, P.; Marques, J. M.; Eggenkamp, H.

2012-12-01

At Sahel, near one of the seaside resort available in Tunisia, the water quantity and quality is a major problem ever at southern center of Tunisia. The Oued Laya coastal system is no exception. The levels, a shallow aquifer up to depths of about 60 m whose reservoir is mainly formed by Mio-Pliocnesediments (with some gypsum lenses dispersed within the geological formations) and deep aquifer, situated between 100 and 250 m depth, located in the Miocene sandstone formations. The results of geochemical and isotopic studies have shown that groundwater salinity seems not be linked with the increasing water well's abstraction. In contrast, water mineralization seems to acquired by dissolution of minerals in the aquifer system especially halie and gypsum. Besides ion exchange processes play also an important role in the groundwater mineralization. Therefore, it clearly appears that several sources might contribute with different mineralization to the selenization of the aquifer through the natural recharge and also through the return of water irrigation. The contamination of the Mio-Pliocene shallow aquifer by a mixture with seawater is confirmed, and stable isotopes data do not support the hypothesis of mixing with seawater. (Author)

The Pliocene initiation and Early Pleistocene volcanic disruption of the palaeo-Gediz fluvial system, Western Turkey

NARCIS (Netherlands)

Maddy, D.; Demir, T.; Bridgland, D.R.; Veldkamp, A.; Stemerdink, C.; Schriek, van der T.; Schreve, D.

2007-01-01

In this paper, we report our latest observations concerning a Pliocene and Early Pleistocene record from Western Turkey. The sedimentary sequence described comprises the fluvial deposits of an Early Pleistocene palaeo-Gediz river system and its tributaries prior to the onset of volcanism around Kula

Mio-Pliocene glaciations of Central Patagonia: New evidence and tectonic implications Glaciaciones mio-pliocenas en Patagonia central: nueva evidencia e implicancias tectónicas

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Yves Lagabrielle

2010-07-01

Full Text Available Patagonia is well known for spectacular oceurrences of a variety of glacial-derived landforms and deposits and for a long history of ancient glaciations. In this paper, we first review the diverse evidence that demonstrates the development of glacial-related sedimentary units within the Central Patagonian Cordillera since 7 Ma. Well preserved glacial landforms at the top surface of mesetas on both sides of the Lago General Carrera-Buenos Aires are described: the Meseta Guenguel to the north, and the volcanic Meseta del Lago Buenos Aires to the south. The latter meseta corresponds to a 3 Ma old, morphologically inverted paleo-piedmont, based on Ar/Ar dates of the uppermost lava flows. It shows evidence of glacier advances to the NE direction. Over a distance of 20 km, glacial landforms observed by remote sensing data and digital elevation model define glacial tongues that were fed by the Cordillera reliefs to the west. These lobes are now beheaded from their westward sources along a morpho-structural corridor that bounds the Meseta del Lago Buenos Aires to the west. These remnants can be correlated with the oldest glacial landforms recognized north of Lago General Carrera-Buenos Aires, on the Meseta Guenguel that form the Chipanque moraine system. From these features it is concluded that the glacial drainage network of Central Patagonia has been strongly modified following relief inversion in response to erosion processes and to tectonic causes. Changes occurred after 3 Ma, from a smooth piedmont surface covered by an extensive ice mantle ending with ampie glacial lobes, to the current series of deeply incised glacial valleys such as the Lago General Carrera-Buenos Aires depression. These new data bear important con-straints on the history and development of the first glaciations in southern South America.Patagonia es bien conocida por una espectacular geomorfología glacial y por una larga historia de antiguas glaciaciones. En este artículooprimero se describe la variada evidencia que demuestra el desarrolloo, desde hace 7 Ma, de unidades sedimentarias glacigénicas en la Cordillera Patagónica Central. Luego se describe una bien preservada geomorfología glacial en la cima de mesetas expuestas a ambos lados del lago General Carrera-Buenos Aires: en la Meseta Guenguel en el lado norte y en la meseta volcánica del lago Buenos Aires en el lado sur. Esta última corresponde a un paleo-piedemonte morfológicamente invertido de 3 Ma acorde a edades Ar/Ar de las lavas basálticas superiores. Exhibe evidencia del avance de glaciares hacia el NE. Observaciones hechas con sensores remotos y con modelos de elevación digital evidenciaron la presencia de formas glaciales a loolargo de una distancia de 20 km, las que fueron alimentadas desde los relieves cordilleranos ubicados al oeste. Estos lóbulos están ahora descabezados de su fuente ubicada al oeste a loolargo de un corredor morfoestructural que limita la Meseta del lago Buenos Aires por el oeste. Estos remanentes pueden ser correlacionados con las formas glaciales más antiguas reconocidas al norte del lago General Carrera-Buenos Aires en la Meseta Guenguel y que forman el sistema de morrenas Chipanque. Sobre la base de estos antecedentes se concluye que el sistema de drenaje de la Patagonia Central ha sido fuertemente modificado subsecuentemente a la inversion del relieve en respuesta a procesos erosivos y a causas tectónicas. Hubo cambios después de 3 Ma, desde una suave superficie de piedemonte cubierta por un extenso manto de hielooterminando con amplios lóbulos glaciales, hasta la actual serie de valles glaciales profundamente incididos tales como la depresión del lago General Carrera-Buenos Aires. Estos nuevos datos entregan importantes antecedentes a la historia y desarrolloode las primeras glaciaciones cenozoicas del sur de América del Sur.

Reservoir characteristics of middle pliocene deposits and their role in the formation of oil gas deposits of Azerbaijan shelf of the south Caspian

International Nuclear Information System (INIS)

Veliyeva, V.A.; Kabulova, A. Ya.

2002-01-01

Full text :Lithology-stratigraphical peculiarities of deposits of lower stage of productive series (P S) of Middle Pliocene their reservoir properties, correlation of individual horizons within the uplifts of the south Caspian was studied. Analysis of arenosity of lower stage of PS was studied. Azerbaijan shelf of South Caspian is located within depression zone of sedimentation basin generally, of Pliocene and post-Pliocene period of time, when sedimentation was mostly intensive and occurred in conditions of more deep sea basin. Azerbaijan shelf of south Caspian covers mainly two oil-gasp-bearing region as Absheron archipelago (north, north-eastern part of region) and Baku archipelago (southern part). Analysis of arenosity along the areas of the studied region showed, that in south-eastern direction and on the south eastern subsidence of each fold, as well as on the north-eastern wing their sand percent considerably increase whereas reservoir properties of sandy interbeds are improved

Diminuição do teor de óxido de crômio (III usado como marcador externo Reduction in chromium (III oxide level as an external marker

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Hermann Bremer Neto

2003-04-01

Full Text Available A sensibilidade do método espectrofotométrico da s-difenilcarbazida de determinação do crômio permite que esse metal possa ser determinado em teores e em massas de amostras tão pequenas que as concentrações atualmente usadas de óxido de crômio (III como marcador externo em ensaios biológicos poderiam ser drasticamente diminuídas. Utilizando-se do piauçu (Leporinus macrocephalus para um estudo sobre o coeficiente de digestibilidade aparente (CDA da fração protéica, seis níveis de óxido de crômio (III - 0,01% - 0,02% - 0,03% - 0,05% - 0,1% e 0,2% - foram incorporados em dietas isoprotéica e isoenergética, objetivando-se verificar se o cálculo do CDA seria afetado pela variação do teor do marcador. Os seis tratamentos foram dispostos em um delineamento em blocos inteiramente casualisados, sendo as fezes coletadas durante 16 dias. Verificou-se que os resultados do coeficiente de digestibilidade aparente da fração protéica não apresentaram diferenças estatísticas significativas devidas aos teores incorporados do marcador à ração e aos dias de coleta. Conseqüentemente, e em experimentos dessa natureza, nada impede que seja reduzido o teor de óxido de crômio (III ao menos até 0,01%: além da economia relativa ao consumo do mesmo e da facilidade na manipulação de menor quantidade de amostras de fezes, o método espectrofotométrico da s-difenilcarbazida permite dosar esse nível (e até menor do que 0,01% de modo simples e rápido, com precisão e exatidão.The objective of this study was to reduce the level of the biological marker Cr2O3 in animal diets, due to the sensibility of the sdiphenylcarbazide spectrophotometric method for chromium determination in feces, recently developed. Six levels of marker, chromium (III oxide (0.01% - 0.02% - 0.03% - 0.05% - 0.1% and 0.2%, were incorporated into isoproteic and isoenergetic diets, for the apparent digestibility assay of the "piauçu" (Leporinus macrocephalus, in a

Provenance analysis of the Pliocene Ware Formation in the Guajira Peninsula, northern Colombia: Paleodrainage implications

Science.gov (United States)

Pérez-Consuegra, Nicolás; Parra, Mauricio; Jaramillo, Carlos; Silvestro, Daniele; Echeverri, Sebastián; Montes, Camilo; Jaramillo, José María; Escobar, Jaime

2018-01-01

The Cocinetas Basin in the Guajira Peninsula, the northernmost tip of South America, today has a dry climate with low rainfall (ten months) and no year-long rivers or permanent standing bodies of fresh water. In contrast, the fossil and geological record indicate that the Cocinetas Basin was much wetter during the Miocene-Pliocene (∼17-2.8 Ma). Water needed to sustain the paleofauna could either have originated from local sources or been brought by a larger river system (e.g. proto Magdalena/Orinoco river) with headwaters either in Andean ranges or the Guyana shield. We present a provenance study of the Pliocene Ware Formation, using petrographic analysis of conglomerate clasts and heavy minerals, and U-Pb dating of 140 detrital zircons. Clasts and heavy minerals are typical of ensialic metamorphic and igneous sources. The detrital zircon age distribution indicates the Guajira ranges as the most probable sediment source. The overall results indicate that the fluvial system of the Ware Formation drained the surrounding ranges. The water was probably derived by local precipitation onto the Guajira peninsula.

Pliocene cooling enhanced by flow of low-salinity Bering Sea water to the Arctic Ocean.

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Horikawa, Keiji; Martin, Ellen E; Basak, Chandranath; Onodera, Jonaotaro; Seki, Osamu; Sakamoto, Tatsuhiko; Ikehara, Minoru; Sakai, Saburo; Kawamura, Kimitaka

2015-06-29

Warming of high northern latitudes in the Pliocene (5.33-2.58 Myr ago) has been linked to the closure of the Central American Seaway and intensification of North Atlantic Deep Water. Subsequent cooling in the late Pliocene may be related to the effects of freshwater input from the Arctic Ocean via the Bering Strait, disrupting North Atlantic Deep Water formation and enhancing sea ice formation. However, the timing of Arctic freshening has not been defined. Here we present neodymium and lead isotope records of detrital sediment from the Bering Sea for the past 4.3 million years. Isotopic data suggest the presence of Alaskan glaciers as far back as 4.2 Myr ago, while diatom and C37:4 alkenone records show a long-term trend towards colder and fresher water in the Bering Sea beginning with the M2 glaciation (3.3 Myr ago). We argue that the introduction of low-salinity Bering Sea water to the Arctic Ocean by 3.3 Myr ago preconditioned the climate system for global cooling.

Polar Frontal Migration in the Warm Late Pliocene: Diatom Evidence from The Wilkes Land Margin, East Antarctic

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Riesselman, C. R.; Taylor-Silva, B.; Patterson, M. O.

2017-12-01

The Late Pliocene is the most recent interval in Earth's history to sustain global temperatures within the range of warming predicted for the 21st century. Published global reconstructions and climate models find an average +2° C summer SST anomaly relative to modern during the 3.3-3.0 Ma PRISM interval, when atmospheric CO2 concentrations last reached 400 ppm. Here, we present a new diatom-based reconstruction of Pliocene interglacial sea surface conditions from IODP Site U1361, on the East Antarctic continental rise. U1361 biogenic silica concentrations document the alternation of diatom-rich and diatom-poor lithologies; we interpret 8 diatom-rich mudstones within this sequence to record interglacial periods between 3.8 and 2.8 Ma. We find that open-ocean conditions in the mid-Pliocene became increasingly influenced by sea ice from 3.6-3.2 Ma, prior to the onset of Northern Hemisphere glaciation. This cooling trend was interrupted by a temporary southward migration of the Antarctic Polar Front, bathing U1361 in warmer subantarctic waters during a single interglacial, marine isotope stage KM3 (3.17-3.15 Ma), that corresponds to a maximum in summer insolation at 65°S. Following this interval of transient warmth, interglacial periods became progressively cooler starting at 3 Ma, coinciding with a transition from obliquity to precession as the dominant orbital driver of Antarctic ice sheet fluctuations. Building on the identification of a single outlier interglacial within the PRISM interval, we have revisited older reconstructions to explore the response of the Southern Ocean/cryosphere system to peak late Pliocene warmth. By applying a modern chronostratigraphic framework to those low-resolution "mean interglacial" records, we identify the same frontal migration in 4 other cores in the Pacific sector of the Southern Ocean, documenting a major migration of the polar front during a key interval of warm climate. These new results suggest that increased summer

Direct radiocarbon dates for Vindija G1 and Velika Pećina Late Pleistocene hominid remains

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Smith, Fred H.; Trinkaus, Erik; Pettitt, Paul B.; Karavanić, Ivor; Paunović, Maja

1999-01-01

New accelerator mass spectrometry radiocarbon dates taken directly on human remains from the Late Pleistocene sites of Vindija and Velika Pećina in the Hrvatsko Zagorje of Croatia are presented. Hominid specimens from both sites have played critical roles in the development of current perspectives on modern human evolutionary emergence in Europe. Dates of ≈28 thousand years (ka) before the present (B.P.) and ≈29 ka B.P. for two specimens from Vindija G1 establish them as the most recent dated Neandertals in the Eurasian range of these archaic humans. The human frontal bone from Velika Pećina, generally considered one of the earliest representatives of modern humans in Europe, dated to ≈5 ka B.P., rendering it no longer pertinent to discussions of modern human origins. Apart from invalidating the only radiometrically based example of temporal overlap between late Neandertal and early modern human fossil remains from within any region of Europe, these dates raise the question of when early modern humans first dispersed into Europe and have implications for the nature and geographic patterning of biological and cultural interactions between these populations and the Neandertals. PMID:10535913

Pliocene taxodiaceous fossil wood from southwestern Ukraine and its palaeoenvironmental implications

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Yi Tiemei

2013-10-01

Full Text Available Mineralized wood collected from Late Pliocene strata near Gorbki village in the Transcarpathian region of Beregovo Kholmogor'e in southwestern Ukraine was anatomically studied and identified. The wood possesses distinctive anatomical features and has distinct growth rings with an abrupt transition from early- to late-wood. Wood consists of tracheids with 1–3 seriate, dominating bi-seriate, opposite pits on the radial walls and taxodioid cross-field pitting, indentures present. Rays are uni-seriate and 1 to 73 cells high. Ray parenchyma horizontal walls thin and smooth. Axial parenchyma distributed in early- and late-wood and is solitary and diffuse, with end walls nearly smooth or slightly nodular. The combination of features observed in the wood indicates it belongs to the conifer family Taxodiaceae and is most similar to modern Sequoia and assigned to the fossil genus Sequoioxylon. Comparison with species of Sequoioxylon show it is most similar to Sequoioxylon burejense, but ray tracheids were not found in our specimens. We describe the specimens here as Sequoioxylon cf. s. burejense noting this similarity. Extant Sequoia is distributed in the northern California coastal forest eco-region of northern California and southern Oregon in the United States where they usually grow in a unique environment with heavy seasonal precipitation (2500 mm annually, cool coastal air and fog drip. This study supplies magafossil evidence of Sequoioxylon as an element of the Late Pliocene forest community in Ukraine and indicates a climate with heavy seasonal precipitation and fog drip.

Sub-Milankovitch cycles in periplatform carbonates from the early Pliocene Great Bahama Bank

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Reuning, Lars; Reijmer, John; Betzler, C.; Timmermann, A.; Steph, Silke

2006-01-01

High-resolution bulk sediment (magnetic susceptibility and aragonite content) and δ18O records from two different planktonic foraminifera species were analyzed in an early Pliocene core interval from the Straits of Florida (Ocean Drilling Program site 1006). The δ18O record of the shallow-dwelling foraminifera G. sacculifer and the aragonite content are dominated by sub-Milankovitch variability. In contrast, magnetic susceptibility and the δ18O record of the deeper-dwelling foraminifera G. me...

The evolution of seabirds in the Humboldt Current: new clues from the Pliocene of Central Chile.

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Martín Chávez Hoffmeister

Full Text Available During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap.Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified.The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current.

Qualidade da carne de frangos de corte submetidos a dietas suplementadas com crômio, criados em diferentes temperaturas ambientais = Meat quality of broiler chicks submeted the supplemented diets with chromium and reared in differents enviromental temperatures

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Alexandre Oba

2007-04-01

Full Text Available Foram realizados dois experimentos. O experimento um objetivou avaliar a composição da carne do peito de frangos alimentados com dietas suplementadas com crômio (0, 400, 800 e 1.200 μg Cr kg-1 complexado a levedura, criados sob diferentes condições de temperatura (quente, termoneutra e fria. O experimento dois objetivou avaliar a qualidade da carne do peito de frangos alimentados com dietas suplementadas com crômio (0 e 400 μg Cr kg-1, criados nas mesmas condições do experimento um e desossados em diferentes períodos (0, 5 e 24 horas. Os resultados mostram que as aves criadas em ambiente frio apresentaram a carne com menor porcentagem de matéria mineral e crômio e maior intensidade de vermelho, enquanto as aves criadas em temperatura termoneutra apresentaram carne com menor porcentagem de umidade, e as aves criadas em temperatura quente, carne com maior luminosidade. Já a suplementação de crômio não proporcionou qualquer efeito na composição e na qualidade de carne, enquanto que o aumento no período de desossa proporcionou um menor comprimento de sarcômero, força de cisalhamento e intensidade de amarelo, porém uma maior luminosidade.Two experiments were conducted being the objective of the first experiment to evaluate the the composition of breast meat of broiler chicks fed with diets supplemented with chromium yeast (0; 400; 800and 1,200 μg Cr kg-1 reared in different environmental temperatures (hot, thermoneutral and cold. The second experiment aimed to evaluate the quality of breast meat of broiler chicks fed with diets supplemented with chromium yeast (0 and 400 μg Cr kg-1, reared in different environmental temperatures (hot, thermoneutral and cold and deboned in different periods (0, 5 and 24 hours. The results showed that birds reared in cold environmental temperature showed meat with lower mineral matter percentage and chromium and higher values of redness, whereas the birds reared in thermoneutral environment

Paleocommunity turnover in an Early Pliocene seamount from southeastern Spain

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García-Ramos, Diego Antonio; Zuschin, Martin

2017-04-01

Seamounts are topographic elevations under the sea, regardless of their size and relief. They support rich living communities and are important biodiversity hotspots, but many of the fundamental ecological processes that maintain seamount communities remain poorly understood. In contrast to snapshot observations conducted on extant seamounts, fossil examples may provide the opportunity to assess how temporal changes in physico-chemical parameters relate to paleocommunity turnovers in these particular biotopes. Here we deal with an Early Pliocene (Zanclean) small seamount in southeastern Spain. This classic locality is extremely rich in fossil macroinvertebrates and was subject to studies of some taxonomic groups in the late seventies. However, the detailed stratigraphy is herein outlined for the first time. The overall feature is a shallowing upward succession about 35 m thick which onlaps a Miocene volcanic ridge. The occurrence of the planktonic foraminifera Globorotalia margaritae and G. puncticulata allow attribution to the MPl3 biozone of the Mediterranean Pliocene. We measured two sections that can be divided in a lower interval of fine-grained bryozoan-rich deposits and a upper interval of biocalcarenite increasingly rich in rhodoliths upsection. The whole series is bioturbated, with Thalassinoides traces being more common upsection. Biofabrics comprise mostly densely-packed suites of disarticulated and fragmented shells of calcitic fauna (large oysters are often bioeroded by clionid sponges), suggesting relatively low sedimentation rates and reworking by storms (e.g., channelized shell-beds, tubular tempestites). The prevailing taxonomic groups are cheilostome bryozoans, oysters, brachiopods, pectinids, echinoderms, cirripedes and corals. The lower interval contains octocoral internodes (Isididae) (only recorded at the base of the section). Scleratinians like Balanophyllia? decrease in abundance upsection. Bryozoans are extremely abundant and diverse, with

Into Tibet: An Early Pliocene Dispersal of Fossil Zokor (Rodentia: Spalacidae) from Mongolian Plateau to the Hinterland of Tibetan Plateau.

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Li, Qiang; Wang, Xiaoming

2015-01-01

This paper reports the fossil zokors (Myospalacinae) collected from the lower Pliocene (~4.4 Ma) of Zanda Basin, southwestern Tibet, which is the first record in the hinterland of Tibetan Plateau within the Himalayan Range. Materials include 29 isolated molars belonging to Prosiphneus eriksoni (Schlosser, 1924) by having characters including large size, highly fused roots, upper molars of orthomegodont type, m1 anterior cap small and centrally located, and first pair of m1 reentrants on opposing sides, high crowns, and high value of dentine tract parameters. Based on the cladistics analysis, all seven species of Prosiphneus and P. eriksoni of Zanda form a monophyletic clade. P. eriksoni from Zanda, on the other hand, is nearly the terminal taxon of this clade. The appearance of P. eriksoni in Zanda represents a significant dispersal in the early Pliocene from its center of origin in north China and Mongolian Plateau, possibly via the Hol Xil-Qiangtang hinterland in northern Tibet. The fast evolving zokors are highly adapted to open terrains at a time when regional climates had become increasingly drier in the desert zones north of Tibetan Plateau during the late Miocene to Pliocene. The occurrence of this zokor in Tibet thus suggests a rather open steppe environment. Based on fossils of large mammals, we have formulated an "out of Tibet" hypothesis that suggests earlier and more primitive large mammals from the Pliocene of Tibet giving rise to the Ice Age megafauna. However, fossil records for large mammals are still too poor to evaluate whether they have evolved from lineages endemic to the Tibetan Plateau or were immigrants from outside. The superior record of small mammals is in a better position to address this question. With relatively dense age intervals and numerous localities in much of northern Asia, fossil zokors provide the first example of an "into Tibet" scenario--earlier and more primitive taxa originated from outside of the Tibetan Plateau and the

Cosmogenic nuclides constrain surface fluctuations of an East Antarctic outlet glacier since the Pliocene.

OpenAIRE

Jones, R.S.; Norton, K.P.; Mackintosh, A.N.; Anderson, J.T.H.; Kubik, P.; Vockenhuber, C.; Wittman, H.; Fink, D.; Wilson, G.S.; Golledge, N.R.; McKay, R.

2017-01-01

Understanding past changes in the Antarctic ice sheets provides insight into how they might respond to future climate warming. During the Pliocene and Pleistocene, geological data show that the East Antarctic Ice Sheet responded to glacial and interglacial cycles by remaining relatively stable in its interior, but oscillating at its marine-based margin. It is currently not clear how outlet glaciers, which connect the ice sheet interior to its margin, responded to these orbitally-paced climate...

Variations of the Indian summer monsoon over the Mio-Pliocene recorded in the Bengal Fan (IODP Exp354): implications for the evolution of the terrestrial biosphere.

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Galy, Valier; Feakins, Sarah; Karkabi, Elias; Ponton, Camilo; Galy, Albert; France-Lanord, Christian

2017-04-01

A pressing challenge in climate research is understanding the temporal evolution of the Indian monsoon system; its response to global and regional climatic controls (including warming); as well as implications in terms of vegetation (C4 expansion), erosion of the Himalaya and carbon sequestration in the Bengal Fan. Studies on climate dynamics have recently offered new insights into the mechanistic controls on the monsoon: the tectonic boundary of the Himalaya is implicated as the major control on Indian summer monsoon dynamics today. Since this region has been uplifted since at least the late Oligocene, it is possible to test the response of monsoon precipitation to global and regional climate change, and also understand feedbacks on the climate system via carbon sequestration in the Bengal Fan. The evidence for monsoon intensity changes across the Miocene and Pliocene is currently incomplete given temporal uncertainty and diagenesis in terrestrial records; biases in the records reconstructed from the distal fan; and conflicting evidence from wind speed and aridity metrics for a stronger or weaker monsoon. Our alternative approach is therefore to study the basin-wide hydrological changes recorded in a multi-proxy, multi-site study of the marine sediments of the Bengal Fan recovered during IODP expedition 354. In turbiditic sediments of Himalayan origin, the late Miocene C4 expansion was found in all three long records recovered during expedition 354 (i.e. at sites U1451, U1450 and U1455, from East to West) based on stable carbon isotope composition of terrestrial leaf-wax compounds. Cores from sites U1455 (a reoccupation of DSDP Leg 22 Site 218) provide the highest resolution record of the C4 transition, which appears to occur abruptly within a relatively continuous series of turbiditic sequences. Bio- and magneto-stratigraphic dating of these records by members of Expedition 354 science party is underway and will provide the best stratigraphic constraint of the C4

Application of groundwater sustainability indicators to the Upper Pliocene aquifer in Ho Chi Minh city, Viet Nam

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Ngo, T. M.; Lee, J.; Lee, H.; Woo, N. C.

2013-12-01

Groundwater plays an importance role for domestic, industrial, and agricultural uses in Ho Chi Minh city, Viet Nam. This study is objected to evaluate the sustainability of groundwater by using groundwater sustainability indicators (GWSIs) defined by UNESCO/IAEA/IAH Working Group on Groundwater Indicators at aquifer scale (the Upper Pliocene aquifer). There are four main indicators selected and one new indicator designed for the particular characteristic of Ho Chi Minh city which is under influence of by saline-water intrusion. The results indicated groundwater of the Upper Pliocene aquifer, the main groundwater supply source, is generally in the unsustainable state. The abstraction of groundwater, which was much greater than its capability, is probably causing the serious state of annual groundwater depletion and saline-water intrusion. The GWSIs, which expressed in such a simple way but scientifically-based and policy-relevant, proved its usefulness in evaluating the sustainability of groundwater at the aquifer scale in Ho Chi Minh city, and subsequently should be incorporated in water resource management practices.

Late Pliocene and Quaternary Eurasian locust infestations in the Canary Archipelago

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Meco, J.; Muhs, D.R.; Fontugne, M.; Ramos, A.J.; Lomoschitz, A.; Patterson, D.

2011-01-01

The Canary Archipelago has long been a sensitive location to record climate changes of the past. Interbedded with its basalt lavas are marine deposits from the principal Pleistocene interglacials, as well as aeolian sands with intercalated palaeosols. The palaeosols contain African dust and innumerable relict egg pods of a temperate-region locust (cf. Dociostaurus maroccanusThunberg 1815). New ecological and stratigraphical information reveals the geological history of locust plagues (or infestations) and their palaeoclimatic significance. Here, we show that the first arrival of the plagues to the Canary Islands from Africa took place near the end of the Pliocene, ca. 3Ma, and reappeared with immense strength during the middle Late Pleistocene preceding MIS (marine isotope stage) 11 (ca. 420ka), MIS 5.5 (ca. 125ka) and probably during other warm interglacials of the late Middle Pleistocene and the Late Pleistocene. During the Early Holocene, locust plagues may have coincided with a brief cool period in the current interglacial. Climatically, locust plagues on the Canaries are a link in the chain of full-glacial arid-cold climate (calcareous dunes), early interglacial arid-sub-humid climate (African dust inputs and locust plagues), peak interglacial warm-humid climate (marine deposits with Senegalese fauna), transitional arid-temperate climate (pedogenic calcretes), and again full-glacial arid-cold climate (calcareous dunes) oscillations. During the principal interglacials of the Pleistocene, the Canary Islands recorded the migrations of warm Senegalese marine faunas to the north, crossing latitudes in the Euro-African Atlantic. However, this northward marine faunal migration was preceded in the terrestrial realm by interglacial infestations of locusts. ??? Locust plagues, Canary Islands, Late Pliocene, Pleistocene, Holocene, palaeoclimatology. ?? 2010 The Authors, Lethaia ?? 2010 The Lethaia Foundation.

New fission-track ages of mio-pliocene tuffs in the Sierras Pampeanas and Precordillera of Argentina

International Nuclear Information System (INIS)

Tabbutt, K.; Naeser, C.W.; Jordan, T.E.; Cerveny, P.F.

1989-01-01

Fission-track dates were determined for 18 volcanic tuff horizons located in nine Neogene foreland basin sequences distributed throughout the Precordillera and Sierras Pampeanas of Northwestern Argentina, an area of nearly horizontal subduction. These and other data indicate that a lower age limit for the sedimentary sequences studied is approximately 17 Ma. Therefore these fission-track dates constrain both the history of volcanic activity and the time of deposition in several foreland basins from the middle Miocene to Recent. Although the dates range from 3.6±0.8 Ma to 17.0±1.9 Ma, there is a marked increase in the number of ashes younger than 9 Ma. This implies that two distinct episodes of volcanic activity affected the region. The source of some of these tuffs is unknown but they are probably limited to the 'flat-slab' region between 27 deg and 32 deg S. Tuffs at Rio Blanco and Santa Florentina that are spatially associated with the Mogotes dacite domes of the Famatina Range represented magmatism bracketed from about 7 to 4 Ma in the region underlain by the flat-subducted plate. The stratigraphic relations in the basins show that the faulting that uplifted Sierra de Famatina was contemporaneous with the volcanism which reached the surface along the bounding faults. (Author) [es

Septímio Severo e a Consecratio de Pertinax: rituais de morte e poder Septimius Severus and the Pertinaces' Consecratio: death and power rithuals

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Ana Teresa Marques Gonçalves

2007-01-01

Full Text Available Nosso objetivo neste artigo é analisar a cerimônia de deificação do Imperador Pertinax, que ocorreu após a sua morte, como definia a tradição romana, e foi promovida pelo seu sucessor, o Imperador Lúcio Septímio Severo. Esta cerimônia encontra-se descrita com riqueza de detalhes na obra de Dion Cássio, intitulada História Romana.Our aim is analyze the Emperor Pertinaces' deification cerimony, which occurred after his death, as defined by the Roman tradition, promoted by his successor, the Emperor Lucius Septimius Severus. That ceremony is described in detail in Dio Cassius' work, Roman History.

"En el monumento Resuçitest, fust alos ynfiernos": ¿Error del poeta o influencia de una fuente en el Cantar de Mio Cid?

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Marcelo Rosende

2007-11-01

Full Text Available The present work returns to verses 358-361 of the Cantar de Mio Cid, about a theme that disturbed to the critics: the text of the Códice de Vivar ar refers Jesus resuscitated first, and at last descended to Hell, and that means a reversal of the traditional plot order. Accordingly, I check the different opinions on the matter, in two groups: those that says the poet made a mistake, and those that affirm the autor of the poem suscribe to one model coming of the french epic or the liturgy. Besides, the work intends manage to a solution for considering more satisfactorily the specificity of the manuscript text.

Chronology of Miocene-Pliocene deposits at Split Mountain Gorge, Southern California: A record of regional tectonics and Colorado River evolution

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Dorsey, R.J.; Fluette, A.; McDougall, K.; Housen, B.A.; Janecke, S.U.; Axen, G.J.; Shirvell, C.R.

2007-01-01

Late Miocene to early Pliocene deposit at Split Mountain Gorge, California, preserve a record of basinal response to changes in regional tectonics, paleogeography, and evolution of the Colorado River. The base of the Elephant Trees Formation, magnetostratigraphically dated as 8.1 ?? 0.4 Ma, provides the earliest well-dated record of extension in the southwestern Salton Trough. The oldest marine sediments are ca. 6.3 Ma. The nearly synchronous timing of marine incursion in the Salton Trough and northern Gulf of California region supports a model for localization of Pacific-North America plate motion in the Gulf ca. 6 Ma. The first appearance of Colorado River sand at the Miocene-Pliocene boundary (5.33 Ma) suggests rapid propagation of the river to the Salton Trough, and supports a lake-spillover hypothesis for initiation of the lower Colorado River. ?? 2007 Geological Society of America.

Magnetic minerals in Pliocene and Pleistocene marine marls from Southern Italy : rock magnetic properties and alteration during thermal demagnetization

NARCIS (Netherlands)

Van Velzen, A.J.

1994-01-01

The rock magnetic properties of two different Pliocene to Pleistocene marine marls from southern Italy are studied. Different conditions during sedimentation have led to two completely different magnetic mineralogies in these marls. Chapters 2, 3 and 4 examine the rock magnetic properties of the

The Messinian/Early Pliocene transition in Eastern Mediterranean: New palaeoenvironmental data from the Kalamaki section (Zakynthos Island, Greece)

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Drinia, Hara; Antonarakou, Assimina; Tsourou, Theodora; Tzortzaki, Evi; Filippidi, Amalia; Nikolaou, Konstantinos

2010-05-01

The purpose of this study is to describe the Miocene-Pliocene microfaunal development, and to discuss its palaeoenvironmental and palaeogeographical significance. The studied section (Kalamaki section) is located in the eastern part of Zakynthos Island (western Greece). Details on lithology and stratigraphy of the section are given in Dermitzakis (1978) and Nikolaou (1986). Planktonic species indicate that sediments span the interval which corresponds to MPL1 Zone (Zanclean, early Pliocene) which is in accordance with the biostratigraphic configuration of Rouchy et al. (1992) and Pierre et al. (2006). The studied interval is characterized by the Sphaeroidinellopsis Acme Zone and the presence of Globorotalia margaritae. The recognized succession of microfossil assemblages serves to interpret the evolution of some palaeoenvironmental factors (waterdepth, salinity and oxygen content), whereas the planktonic foraminiferal zonation allows an age assignment to the events. During the Late Messinian brackish conditions became dominant. The early Pliocene is characterized by a sudden return to well oxygenated, open marine, outer shelf conditions. At the basal part of the record, the high abundance of the 'shallow water component' of the benthic foraminiferal fauna indicates a well-vegetated environment with either normal marine salinity or a tendency to hyposalinity (e.g. Murray, 2006). Open marine conditions are indicated by the diversity of benthic and planktonic foraminifera. The abundance of Lenticulina spp., Cibicidoides pseudoungerianus, Planulina ariminensis, Pullenia, Gyroidina, and the virtual absence of Cibicidoides dutemplei and other typical shelf-taxa, suggest an upper bathyal waterdepth of 300-400 m (cf. Pujos, 1976; Jorissen, 1988). Partly, the abundance of Cibicidoides pseudoungerianus, Bulimina costata and Uvigerina peregrina reflect fluctuations in oxygen content of the bottom waters. However, extreme conditions were never reached during deposition. The

Multi-proxy constraints on sapropel formation during the late Pliocene of central Mediterranean (southwest Sicily)

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Plancq, Julien; Grossi, Vincent; Pittet, Bernard; Huguet, Carme; Rosell-Melé, Antoni; Mattioli, Emanuela

2015-06-01

The late Pliocene (Piacenzian) in the Mediterranean region was punctuated by short-lived episodes of widespread deposition of organic-rich sedimentary layers known as sapropels. The causes of their formation remain a long-standing debate in the science community, and require disentangling the roles of climatic/oceanographic processes that triggered higher primary productivity or enhanced organic matter preservation. The lack of data, especially of sea temperatures at sufficient temporal resolution, is one of the main challenges to solve this debate. Here, we present new organic geochemistry and micropaleontological data from the late Pliocene at Punta Grande/Punta Piccola sections (southwest Sicily) that allow untangling the mechanisms that favored the formation of two sapropel series (noted S and A) in the central Mediterranean area during this period. Sea surface (SSTs) and subsurface temperatures were estimated using three distinct organic geochemical proxies namely the alkenone unsaturation index (UK‧37), the long-chain diol index (LDI) and the tetraether index (TEX86). Reconstructed SSTs are relatively stable throughout the late Pliocene and ∼4 °C higher than modern Mediterranean SSTs, which is consistent with the climatic conditions inferred for this period from paleoclimate modeling. An increase in SST is, however, recorded by UK‧37 and LDI proxies across each sapropel horizon, supporting that the two sapropel series S and A were formed during warmer climate conditions. The comparison of SST data with variations in accumulation rates of total organic carbon and lipid-biomarkers (alkenones, long-chain alkyl diols, archaeal and bacterial tetraethers), and with changes in calcareous nannofossil assemblages, indicates that the studied sapropels might have formed under different environmental conditions. The first series of sapropels (S), deposited between 3.1 and 2.8 Ma, is likely due to a better preservation of organic matter, induced by the development

Sea Surface Temperatures in the Indo-Pacific Warm Pool During the Early Pliocene Warm Period

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Dekens, P. S.; Ravelo, A. C.; Griffith, E. M.

2010-12-01

The Indo-Pacific warm pool (IPWP) plays an important role in both regional and global climate, but the response of this region to anthropogenic climate change is not well understood. While the early Pliocene is not a perfect analogue for anthropogenic climate change, it is the most recent time in Earth history when global temperatures were warmer than they are today for a sustained period of time. SST in the eastern equatorial Pacific was 2-4○C warmer in the early Pliocene compared to today. A Mg/Ca SST at ODP site 806 in the western equatorial Pacific indicates that SST were stable through the last 5Ma (Wara et al., 2005). We generated a G. sacculifer Mg/Ca record in the Indian Ocean (ODP sit 758) for the last 5 Ma, which also shows that IPWP SST has remained relatively stable through the last 5 Ma and was not warmer in the early Pliocene compared today. A recent paper suggests that the Mg/Ca of seawater may have varied through the last 5 Ma and significantly affected Mg/Ca SST estimates (Medina-Elizalde et al., 2008). However, there is considerable uncertainty in the estimates of seawater Mg/Ca variations through time. We will present a detailed examination of these uncertainties to examine the possible range of seawater Mg/Ca through the last 5 Ma. Due to the lack of culturing work of foraminifera at different Mg/Ca ratios in the growth water there is also uncertainty in how changes in seawater Mg/Ca will affect the temperatures signal in the proxy. We will explore how uncertainties in the record of seawater Mg/Ca variations through time and its effect on the Mg/Ca SST proxy potentially influence the interpretation of the Mg/Ca SST records at ODP sites 806 and 758 in the IPWP, and ODP site 847 in the eastern equatorial Pacific. We will also explore how adjustment of the Mg/Ca SST estimates (due to reconstructed Mg/Ca seawater variations) affects the δ18O of water when adjusted Mg/Ca SST estimates are paired with δ18O measurements of the same samples.

Pliocene and Pleistocene chronostratigraphy of continental sediments underlying the Altiplano at La Paz, Bolivia

Science.gov (United States)

Roberts, Nicholas J.; Barendregt, René W.; Clague, John J.

2018-06-01

Continental sediments underlying the Altiplano plateau provide insight into the late Cenozoic evolution of the Central Andes. We characterize the magnetostratigraphy and lithostratigraphy of the upper part of this fill sequence along a transect extending southwestward from the Cordillera Real at La Paz, Bolivia, where it is best exposed. Multiple polarity reversals and the locally extensive, 2.74-Ma Chijini Tuff enable correlation between our six sections and three previously reported sections. The tuff ties the composite polarity sequence to the geomagnetic polarity time scale, demonstrating that the stratigraphic record extends from the latest Gilbert Chron (ca. 3.8 Ma) to the late Olduvai subchron (ca. 1.8 Ma), or possibly Jaramillo subchron (ca. 1.0 Ma). The sequence provides Earth's longest known record of low-latitude glaciation and the only record of Pliocene tropical glaciation. It includes evidence for 16 late Pliocene and Early Pleistocene glaciations, separated by interglacials of sufficient length (>103-104 a) to produce mature soil profiles. Successively larger ice caps formed directly before, during, and after the globally warm mid-Piacenzian (3.265-3.025 Ma), and throughout Plio-Pleistocene climate deterioration. The late Pliocene glacial units predate the onset of widespread Northern Hemisphere continental glaciation and in most cases unambiguously correspond to specific cool peaks of the astronomically tuned, benthic oxygen isotope (δ18O) record, including marine isotope stages MG2, M2, KM2, and G10. The glacial events broadly coincide with those nearer both poles, suggesting inter-hemispheric climate linkages. The early formation and subsequent expansion of ice caps beyond glacier margins of the Last Glacial Maximum suggest that the Cordillera Real likely attained its modern height before ca. 3.4 Ma. The number and timing of glaciations, and long-term sediment accumulation and incision rates suggest that the local Altiplano surface formed by ca

Petrology and geochemistry of the Miocene-Pliocene fluvial succession, Katawaz Basin, Western Pakistan: Implications on provenance and source area weathering

DEFF Research Database (Denmark)

Kasi, Aimal K.; Kassi, Aktar Muhammad; Friis, Henrik

Petrology and geochemistry of sandstones and mudstones of the Miocene Dasht Murgha Group (DMG) and Pliocene Malthanai Formation (MF) of the Pishin Belt (Katawaz Basin), northwestern Pakistan have been carried out to find out their provenance and source area weathering. Sandstones of the Dasht...

Dental microwear texture analysis of late Pliocene Procynocephalus subhimalayanus (Primates: Cercopithecidae) of the Upper Siwaliks, India

Science.gov (United States)

Williams, Frank L'Engle; Holmes, Noelle A.

2012-09-01

Late Pliocene Procynocephalus subhimalayanus from the Upper Siwaliks, India is known from only three specimens. The dietary proclivities of this taxon have implications for reconstructing the paleoecology of the Upper Siwaliks. The dental microwear texture properties of Procynocephalus are compared to those from extant tropical forest primates including Alouatta palliata (n = 11), Cebus apella (n = 13), Gorilla gorilla (n = 9), Lophocebus albigena (n = 15) and Trachypithecus cristatus (n = 12). Dental microwear textures are generated by scanning the surface enamel of Facet 9 using white-light confocal microscopy at 100x. Four variables were extracted from scale-sensitive fractal analysis, and the data were ranked before ANOVA with post-hoc tests of significance and multivariate analyses were performed. Procynocephalus clusters closest to Lophocebus, Cebus and some Gorilla specimens suggesting hard-object feeding characterized a portion of its diet. The dental microwear texture of Procynocephalus supports interpretations of widespread grasslands of the Late Pliocene Kansal Formation (Pinjor zone). The extreme enamel complexity characterizing Procynocephalus may derive from consumption of underground storage organs, or other foods with high grit loads. Foods consumed near ground level carry a heavy load of abrasive minerals possibly contributing to greater enamel surface complexity and textural fill volume.

Integrating geological archives and climate models for the mid-Pliocene warm period.

Science.gov (United States)

Haywood, Alan M; Dowsett, Harry J; Dolan, Aisling M

2016-02-16

The mid-Pliocene Warm Period (mPWP) offers an opportunity to understand a warmer-than-present world and assess the predictive ability of numerical climate models. Environmental reconstruction and climate modelling are crucial for understanding the mPWP, and the synergy of these two, often disparate, fields has proven essential in confirming features of the past and in turn building confidence in projections of the future. The continual development of methodologies to better facilitate environmental synthesis and data/model comparison is essential, with recent work demonstrating that time-specific (time-slice) syntheses represent the next logical step in exploring climate change during the mPWP and realizing its potential as a test bed for understanding future climate change.

Using CAM3 and the Alkenone Method to Understand how Pliocene SST's Affect California and Other Climates Adjacent to Upwelling Regions

Science.gov (United States)

Searles, Z. A.; Otto-Bliesner, B. L.; Rosenbloom, N. A.; Dekens, P. S.

2008-12-01

The Intergovernmental Panel on Climate Change fourth assessment report established with 90% confidence that anthropogenic climate change will result in a warmer world. In order to more fully understand possible future climate, past analogues of warm periods should be analyzed. The early Pliocene is an appropriate analogue because the continental configuration was similar to today and CO2 levels were comparable to present (~100ppm higher than pre-anthropogenic levels). This project has two objectives: 1.To test the atmospheric sensitivity to USGS PRISM2 dataset revised to better approximate proxy data indicating warmer SST's in upwelling regions and 2. To provide early-Pliocene (2.7- 3.5 Ma) SST estimates for ODP site 1018 on the California Margin (36°59.4'N, 123°16.5'W) using the UK'37 SST proxy. Recent UK'37 proxy data reveals that PRISM2 underestimates SST's in Pacific and Atlantic coastal upwelling regions. The sensitivity of the atmosphere to significantly warmer SST's in upwelling regions was tested using the National Center for Atmospheric Research (NCAR) Community Atmospheric Model, version 3 (CAM3). Initial conditions were supplied by the USGS PRISM2 project and include Pliocene SST's, vegetation cover, sea level height, topography, marine and continental ice extent. Pliocene SST's along the Californian, Peruvian, North African and South African margin were modified to reflect proxy observations from 4 sites. The lack of observational coverage (1 data point per region) required interpolation of the areal extent of the SST warming anomaly indicated by the proxies. Experiment results show increased cumulative precipitation and humidity in regions where the original PRISM2 predicted drying. The predicted North American increase in precipitation is in better agreement with geologic proxies indicating wetter conditions. Warmer SST's also causes weaker wind velocities along the North American, Peruvian, and North African margins, and stronger winds along the

A new record of late Pliocene-early Pleistocene aeolian loess-red clay deposits from the western Chinese Loess Plateau and its palaeoenvironmental implications

Science.gov (United States)

Zan, Jinbo; Fang, Xiaomin; Zhang, Weilin; Yan, Maodu; Zhang, Dawen

2018-04-01

The loess-red clay sequences in northern China provide high-resolution terrestrial records of Asian monsoon evolution and aridification of the Asian interior. To date, however, aeolian deposits of late Pliocene-early Pleistocene age (3.5-2.4 Ma) have only rarely been reported from the western Chinese Loess Plateau (CLP), which significantly hinders our understanding of the distribution of aeolian deposits and the palaeoenvironmental evolution of the region. Here, we present magnetostratigraphic, lithologic and magnetic susceptibility results for two recently-drilled boreholes from the north bank of Baxie River, central Linxia Basin, which are highly correlative with those of the loess-red clay deposits spanning the interval from 3.6 to 2.4 Ma in the eastern CLP. Our results provide the first direct evidence for the occurrence of late Pliocene-early Pleistocene aeolian deposits in the western CLP and provide new insights into the distribution of aeolian deposits in northern China. The spatial coherence of the magnetic susceptibility fluctuations further indicates that magnetic susceptibility is a powerful tool for stratigraphic correlation of late Pliocene aeolian deposits in the western CLP. In addition, our results demonstrate that erosional events may have occurred in the early or middle Pleistocene, and they may provide new insights into the reasons for the absence of loess-red clay deposits from 3.5 to 2.4 Ma in most parts of the western CLP.

Latest Miocene-Pliocene Tiliviche Paleolake, Atacama Desert, Northern Chile 19.5°S: Paleoclimatic and Paleohydrologic Implications

Science.gov (United States)

Kirk-Lawlor, N. E.; Jordan, T. E.; Rech, J.; Lehmann, S.

2010-12-01

Endorheic paleolake deposits of diatomite, mudstone, sandstone, and evaporites are exposed in the Atacama Desert of northern Chile. This study focuses on a major latest Miocene-Pliocene paleolake system centered at 19.5°S, near Tiliviche. A diatiomite unit, up to 35m thick, composed of 0.2-1.5m thick beds of massive, white diatiomite, free of plant matter and root traces, is interpreted have formed from lacustrine diatom blooms. At its maximum extent, the lake would have had a surface area of roughly 200 km2, based on the extent of the diatomite unit, and might have been 50-100 m deep, as inferred by the relationship between the diatomite unit and modern topography. The Tiliviche paleolake initially formed before 6.4 Ma, and much of its sedimentary record formed under a wetter climatic and hydrologic regime than the present. Prior to 3.5 Ma, the lake had evolved into a groundwater-fed saltpan. Polygonally fractured efflorescent halite evaporite and bedded gypsum and gypsarenite evaporite deposits that overlie the diatomite unit are evidence of this saltpan environment. The modern Atacama Desert is hyperarid, with an average precipitation of 2 mm/yr in the driest areas. The paleosol record demonstrates that hyperarid conditions dominated this region since the middle Miocene, albeit with multiple fluctuations to less arid conditions of short to moderately long duration. This hyperaridity is due to the desert’s latitude, ocean currents and the rainshadow created by the Andes. There is no evidence that the rainshadow effect has diminished since the late Miocene, hence global climate changes affecting ocean temperatures and atmospheric patterns likely caused the wetter periods in the Atacama. In particular, prior workers noted wetter conditions in the region ~6-5 Ma, followed by a return to hyper-arid conditions. The regional Pliocene return to hyperaridity coincided with the desiccation of the Tiliviche endorheic lake system. During the late Miocene (~6-5 Ma) wetter

Information on governmental and industrial energy RD and expenditures for the year 1997 in Austria

International Nuclear Information System (INIS)

Faninger, G.

1998-04-01

Information on governmental and industrial energy RD and D expenditures for the year 1997 in Austria: The government (state and federal) energy RD and D budget in Austria was 137.6 Mio ATS in 1990, 245.0 Mio ATS in 1991, 210.7 Mio ATS in 1992, 286.9 Mio ATS in 1993, 324.6 Mio ATS in 1994, 332.1 Mio ATS in 1995, 334.3 Mio ATS in 1996 and 354.1 Mio ATS in 1997. The expenditures of the Austrian private industry for energy RD and D are estimated to be about 89 Mio ATS for the year 1990, about 122 Mio ATS for the year 1991, about 98 Mio ATS for the year 1992, about 124 Mio ATS for 1993, about 170 Mio ATS for 1994, about 128 Mio ATS for 1995, about 116 Mio ATS for 1996 and about 133 Mio ATS for 1997. The energy RD and D budget of the Austrian Electricity Companies was 133.3 Mio ATS for 1991, 181.1 Mio ATS for 1992, 192.4 Mio ATS for 1993, 126.6 Mio ATS for 1994, 191.0 Mio ATS for 1995, 207.3 Mio ATS for 1996 and 227.7 Mio ATS for 1997. (author)

Expenditures of the federation as well as the provinces and the industry for energy research, development and demonstration in Austria: inquiry 1996

International Nuclear Information System (INIS)

Faninger, G.

1997-03-01

The government (state and federal) energy RD and D budget in Austria was 137.6 Mio ATS in 1990, 245.0 Mio ATS in 1991, 210.7 Mio ATS in 1992, 286.9 Mio ATS in 1993, 324.6 Mio ATS in 1994, 332.1 Mio, ATS in 1995 and 334.3 Mio ATS in 1996. The expenditures of the Austrian private industry for energy RD and D are estimated to be about 89 Mio ATS for the year 1990, about 122 Mio ATS for the year 1991, about 98 Mio ATS for the year 1992, about 124 Mio AS for 1993, about 170 Mio ATS for 1994, about 128 Mio ATS for 1995 and about 116 Mio ATS for 1996. The energy RD and D budget of the Austrian Electricity Companies was 133.3 Mio ATS for 1991, 181.1 Mio ATS for 1992, 192.4 Mio, ATS for 1993, 126.6 Mio ATS for 1994, 191.0 Mio ATS for 1995 and 207.3 Mio ATS for 1996. (author)

A classe dos polinômios bivariados de Fibonacci (PBF: elementos recentes sobre a evolução de um modelo.

Directory of Open Access Journals (Sweden)

Francisco Regis Vieira Alves

2017-02-01

Full Text Available Se constata na abordagem, por parte dos autores de livros de História da Matemática – HM, uma apreciação lacônica, lúdica e desprovida de um vigor histórico-matemático que proporcione ao leitor um entendimento do processo evolutivo irrefreável hodierno do modelo de Fibonacci, originariamente correspondente ao processo biológico de produção de pares de coelhos. A partir dessa perspectiva, o trabalho atual discute a classe dos Polinômios Bivariados Complexos de Fibonacci – PBCF. Os mesmos constituem uma representação generalizada da Sequência de Fibonacci, em termos de uma variável real ‘x’ e a unidade imaginária ‘i’. Assim, o texto aborda e pormenoriza determinados resultados matemáticos que envidam uma perspectiva correlata ao processo ininterrupto evolutivo do modelo de Fibonacci, costumeiramente negligenciados por autores de livros.

Late Pliocene Northern Hemisphere glaciations: The continental and marine responses in the central Mediterranean

Science.gov (United States)

Nebout, Nathalie Combourieu; Grazzini, Colette Vergnaud

Detailed pollen analyses and oxygen isotope records of three foraminiferal species, Globigerina bulloides, Uvigerina peregrina and Cibicides pachyderma, from the Semaforo and Vrica composite sections (Crotone, southern Italy) have been compared to the global climatic changes depicted by late Pliocene-early Pleistocene foraminiferal δ 18O records of Site 607 in the North Atlantic, and Hole 653A in the Tyrrhenian basin, West Mediterranean. Major overturns in the mid-altitude vegetation are shown near isotopic stages 82, 60, 58 and 50, at about 2.03 Ma, 1.6 Ma and 1.37 Ma according to the Raymo et al. (1989) and Ruddiman et al. (1989) timescales. At the same dates, glacial 18O maxima either became higher or display step increases in the western Mediterranean or in the open ocean as well. This suggests that size increases of Northern Hemisphere ice sheets were the driving factor for regional or local marine and continental environmental changes within the Mediterranean basin. Near isotopic stages 62-60, close to the conventional Plio-Pleistocene boundary, the climatic conditions severed enough within the Mediterranean basin to modify the continental environment, as depicted by a sudden increase of Artemisia percentages, while the first significant southward migration of the North Polar Front may have been recorded by an influx of left coiling Neogloboquadrina pachyderma in the central Mediterranean. It also appears that 'Boreal Guests' entered the Mediterranean during phases of 18O enrichment of foraminiferal calcite. There does not seem to be any discrepancy between the climatic concept of the Pliocene-Pleistocene boundary and its chronostratigraphic definition.

Integrating geological archives and climate models for the mid-Pliocene warm period

Science.gov (United States)

Haywood, Alan M.; Dowsett, Harry J.; Dolan, Aisling M.

2016-01-01

The mid-Pliocene Warm Period (mPWP) offers an opportunity to understand a warmer-than-present world and assess the predictive ability of numerical climate models. Environmental reconstruction and climate modelling are crucial for understanding the mPWP, and the synergy of these two, often disparate, fields has proven essential in confirming features of the past and in turn building confidence in projections of the future. The continual development of methodologies to better facilitate environmental synthesis and data/model comparison is essential, with recent work demonstrating that time-specific (time-slice) syntheses represent the next logical step in exploring climate change during the mPWP and realizing its potential as a test bed for understanding future climate change. PMID:26879640

First record of the megatoothed shark Carcharocles megalodon from the Mio-Pliocene Purisima Formation of Northern California.

OpenAIRE

Boessenecker, Robert W.

2016-01-01

Megatoothed sharks (Family: Otodontidae) are among the most widely reported sharks in Cenozoic marine sediments worldwide, and certain species such as the famed Carcharocles megalodon are particularly abundant in Neogene deposits on the Atlantic margin of the United States. Cenozoic marine strata on the Pacific margin of North America have yielded one of the most densely sampled marine vertebrate records anywhere, but published occurrences of shark assemblages are uncommon. Rarer yet are publ...

Modelling the enigmatic Late Pliocene Glacial Event - Marine Isotope Stage M2

Science.gov (United States)

Dolan, Aisling M.; Haywood, Alan M.; Hunter, Stephen J.; Tindall, Julia C.; Dowsett, Harry J.; Hill, Daniel J.; Pickering, Steven J.

2015-01-01

The Pliocene Epoch (5.2 to 2.58 Ma) has often been targeted to investigate the nature of warm climates. However, climate records for the Pliocene exhibit significant variability and show intervals that apparently experienced a cooler than modern climate. Marine Isotope Stage (MIS) M2 (~ 3.3 Ma) is a globally recognisable cooling event that disturbs an otherwise relatively (compared to present-day) warm background climate state. It remains unclear whether this event corresponds to significant ice sheet build-up in the Northern and Southern Hemisphere. Estimates of sea level for this interval vary, and range from modern values to estimates of 65 m sea level fall with respect to present day. Here we implement plausible M2 ice sheet configurations into a coupled atmosphere–ocean climate model to test the hypothesis that larger-than-modern ice sheet configurations may have existed at M2. Climate model results are compared with proxy climate data available for M2 to assess the plausibility of each ice sheet configuration. Whilst the outcomes of our data/model comparisons are not in all cases straight forward to interpret, there is little indication that results from model simulations in which significant ice masses have been prescribed in the Northern Hemisphere are incompatible with proxy data from the North Atlantic, Northeast Arctic Russia, North Africa and the Southern Ocean. Therefore, our model results do not preclude the possibility of the existence of larger ice masses during M2 in the Northern or Southern Hemisphere. Specifically they are not able to discount the possibility of significant ice masses in the Northern Hemisphere during the M2 event, consistent with a global sea-level fall of between 40 m and 60 m. This study highlights the general need for more focused and coordinated data generation in the future to improve the coverage and consistency in proxy records for M2, which will allow these and future M2 sensitivity tests to be interrogated

Fish fauna of the Camp dels Ninots locality (Pliocene; Caldes de Malavella, province of Girona, Spain) - first results with notes on palaeoecology and taphonomy

Czech Academy of Sciences Publication Activity Database

Přikryl, Tomáš; Gómez de Soler, B.; Oms, O.; Roubach, S.; Blain, H-A.; Agustí, J.

2016-01-01

Roč. 28, č. 3 (2016), s. 347-357 ISSN 0891-2963 Institutional support: RVO:67985831 Keywords : Camp dels Ninots * Cyprinidae * maar lake * NE Spain * Pliocene * Teleostei Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.556, year: 2016

Cross-stratified Wood: Enigmatic Woody Debris Deposits in Warm-Polar Fluvial Sediments (Pliocene Beaufort Formation, Nunavut)

Science.gov (United States)

Davies, N. S.; Gosse, J. C.; Rybczynski, N.

2012-04-01

Woody debris has been an important sediment component and a significant geomorphic agent in pristine fluvial systems since the Devonian. In recent years a large volume of research has focussed on various aspects of the importance of woody debris within the fluvial realm; from the evolutionary significance of fossil wood accumulations in the rock record to studies of the biogeomorphological and ecological importance of woody debris in modern rivers. In this presentation we describe cross-stratified woody debris deposits comprising organic detritus from a boreal-type treeline forest that included species of pine, birch, poplar, alder, spruce, eastern cedar, and larch, in both shrub and tree form. The cross-stratified wood is an enigmatic subset of fine woody debris which, to our knowledge, has never before been described from either the global stratigraphic record or modern fluvial environments. The deposits we describe are located within the Pliocene Beaufort Formation on Meighen Island, Nunavut, Canada, at a latitude of 80°N, and are compared with other cross-stratified woody debris deposits that have been noted elsewhere in the Pliocene of the Canadian Arctic. We make the robust observation that these deposits appear to be geographically and stratigraphically restricted to polar latitudes from a period of warm climatic conditions during the Pliocene (15-20 °C warmer mean annual temperature than the present day). In this regard it is possible to speculate that the transport of large amounts of woody debris as bedload is potentially a unique feature of forested high latitude rivers. Such bedload deposition requires a large amount of woody debris with a greater density than the fluid transporting it. The softwood composition of the debris suggests that this was most likely attained by saturation and subsequent entrainment of extensive accumulations of deadwood, promoted by unusually high rates of tree mortality and low rates of bacterial decomposition arising from

Paleovegetation reconstruction of fossil forests dominated by Metasequoia and Glyptostrobus from the late Pliocene Kobiwako Group, central Japan

OpenAIRE

CHIYOMI, YAMAKAWA; ARATA, MOMOHARA; TOMOO, NUNOTANI; MIDORI, MATSUMOTO; YASUYUKI, WATANO; Lake Biwa Museum; Graduate School of Horticulture, Chiba University; Lake Biwa Museum; Graduate School of Science, Chiba University; Graduate School of Science, Chiba University

2008-01-01

A late Pliocene (1.8-1.9 Ma) wetland fossil forest community that was dominated by Metasequoia and Glyptostrobus was reconstructed based on the species composition of the stumps and other plant macrofossil assemblages. The plant fossils were recovered from a fossil forest preserved in deposits of the Kobiwako Group that are exposed in the Echi River, Shiga Prefecture, central Japan. Fossil wood of Metasequoia and Glyptostrobus was distinguished based on anatomical characteristics. Apportionme...

Contribution of changes in opal productivity and nutrient distribution in the coastal upwelling systems to Late Pliocene/Early Pleistocene climate cooling

Directory of Open Access Journals (Sweden)

J. Etourneau

2012-09-01

Full Text Available The global Late Pliocene/Early Pleistocene cooling (~3.0–2.0 million years ago – Ma concurred with extremely high diatom and biogenic opal production in most of the major coastal upwelling regions. This phenomenon was particularly pronounced in the Benguela upwelling system (BUS, off Namibia, where it is known as the Matuyama Diatom Maximum (MDM. Our study focuses on a new diatom silicon isotope (δ³⁰Si record covering the MDM in the BUS. Unexpectedly, the variations in δ³⁰Si signal follow biogenic opal content, whereby the highest δ³⁰Si values correspond to the highest biogenic opal content. We interpret the higher δ³⁰Si values during the MDM as a result of a stronger degree of silicate utilisation in the surface waters caused by high productivity of mat-forming diatom species. This was most likely promoted by weak upwelling intensity dominating the BUS during the Late Pliocene/Early Pleistocene cooling combined with a large silicate supply derived from a strong Southern Ocean nutrient leakage responding to the expansion of Antarctic ice cover and the resulting stratification of the polar ocean 3.0–2.7 Ma ago. A similar scenario is hypothesized for other major coastal upwelling systems (e.g. off California during this time interval, suggesting that the efficiency of the biological carbon pump was probably sufficiently enhanced in these regions during the MDM to have significantly increased the transport of atmospheric CO₂ to the deep ocean. In addition, the coeval extension of the area of surface water stratification in both the Southern Ocean and the North Pacific, which decreased CO₂ release to the atmosphere, led to further enhanced atmospheric CO₂ drawn-down and thus contributed significantly to Late Pliocene/Early Pleistocene cooling.

Tectonic imprints upon inferences of eustatic sea level history: the Pliocene warm period and the Orangeburg Scarp

Science.gov (United States)

Chandan, D.; Peltier, W. R.

2013-12-01

The issue of tectonic contamination of geological inferences of relative sea level history is an important one. The issue arises on timescales that range from the 21-26 kyrs that have passed since the Last Glacial Maximum, to the most recent time when periods as warm as the present are expected to have existed, such as the mid-Pliocene. The coral based record from Barbados, for example, is known to be contaminated by continuing tectonic uplift of the island at a rate of approximately 0.34 mm/yr. For the Pliocene warm period at ~3 Myr, records from geological sites, such as the Orangeburg Scarp in North Carolina, have played a prominent role in arguments underpinning the design of the ongoing international PlioMIP program. In connection with the latter site, Rowley et al (2013) have recently argued that this record is contaminated by a tectonic imprint sufficiently strong to suggest that the usual inferences of Pliocene eustatic sea level based upon it (eg. Miller et al, 2012) must be seen as highly suspect. Here we employ a tomographically constrained model of the mantle convection process to revisit the issue of the tectonic imprint on relative sea level at the Orangeburg site, as well as other similar locations. Our analysis is based upon the inferred time dependence of dynamic topography forced by the mantle's internal density heterogeneities delivered by the S20RTS seismic tomography model. We begin by comparing the static, present day dynamic topography predicted by the (linear) internal loading theory based on the formalism of Pari and Peltier (2000) with that predicted using using a full three dimensional version of the nonlinear time-dependent mantle convection model of Shahnas and Peltier (2010, 2011). We demonstrate first that these two methodologies produce extremely similar results for the static field. We then proceed to run the nonlinear convection model in data assimilation mode while continuously nudging the internal density field back towards the

First chelonian eggs and carapace fragments from the Pliocene of Rhodes, Greece

DEFF Research Database (Denmark)

Mueller-Töwe, Inken J.; Kjeldahl-Vallon, Tina A.; Milàn, Jesper

2011-01-01

Well-preserved fossil eggs and eggshell fragments from the Pliocene Apolakkia Formation of Rhodes (Greece) are described. The eggs were found in-situ in a clutch. They are sub-spherical with lengths of 53-60 mm and widths of about 40 mm. All eggs are diagenetically compressed and their original...... diameters are estimated at 45-50 mm. The eggshells are 0.3-0.5 mm thick, partly recrystallized, but widely still aragonitic. They consist of needle-like crystals that form individual shell units. A few pores are preserved between these shell units. This shell-structure allows assignment to chelonian eggs...... in the oofamily Testudoolithidae and the oogenus Testudolithus. The external morphology, microstructure and mineralogical composition of the eggshells show close resemblance to eggs of the extant tortoise Geochelone elephantopus. Together with a small association of turtle carapace fragments from the same...

Evaluating climatic response to external radiative forcing during the late Miocene to early Pliocene: New perspectives from eastern equatorial Pacific (IODP U1338) and North Atlantic (ODP 982) locations

Science.gov (United States)

Drury, Anna Joy; John, Cédric M.; Shevenell, Amelia E.

2016-01-01

Orbital-scale climate variability during the latest Miocene-early Pliocene is poorly understood due to a lack of high-resolution records spanning 8.0-3.5 Ma, which resolve all orbital cycles. Assessing this variability improves understanding of how Earth's system sensitivity to insolation evolves and provides insight into the factors driving the Messinian Salinity Crisis (MSC) and the Late Miocene Carbon Isotope Shift (LMCIS). New high-resolution benthic foraminiferal Cibicidoides mundulus δ18O and δ13C records from equatorial Pacific International Ocean Drilling Program Site U1338 are correlated to North Atlantic Ocean Drilling Program Site 982 to obtain a global perspective. Four long-term benthic δ18O variations are identified: the Tortonian-Messinian, Miocene-Pliocene, and Early-Pliocene Oxygen Isotope Lows (8-7, 5.9-4.9, and 4.8-3.5 Ma) and the Messinian Oxygen Isotope High (MOH; 7-5.9 Ma). Obliquity-paced variability dominates throughout, except during the MOH. Eleven new orbital-scale isotopic stages are identified between 7.4 and 7.1 Ma. Cryosphere and carbon cycle sensitivities, estimated from δ18O and δ13C variability, suggest a weak cryosphere-carbon cycle coupling. The MSC termination coincided with moderate cryosphere sensitivity and reduced global ice sheets. The LMCIS coincided with reduced carbon cycle sensitivity, suggesting a driving force independent of insolation changes. The response of the cryosphere and carbon cycle to obliquity forcing is established, defined as Earth System Response (ESR). Observations reveal that two late Miocene-early Pliocene climate states existed. The first is a prevailing dynamic state with moderate ESR and obliquity-driven Antarctic ice variations, associated with reduced global ice volumes. The second is a stable state, which occurred during the MOH, with reduced ESR and lower obliquity-driven variability, associated with expanded global ice volumes.

Paléointensités géomagnétiques absolues complémentaires de la Basse Californie : évaluation des données du Pliocène et du Pléistocène inférieur et moyen

Science.gov (United States)

Morales, Juan; Goguitchaichvili, Avto; Cañon-Tapia, Edgardo; Negrete, Raquel

2003-11-01

From a large collection (more than 300 oriented cores) of Baja California Mio-Pliocene volcanic units, sampled for magnetostratigraphy and tectonics, 46 samples were selected for Thellier paleointensity experiments because of their low viscosity index, stable remanent magnetization and close to reversible continuous thermomagnetic curves. 19 samples, coming from 4 individual basaltic lava flows, yielded reliable paleointensity estimates with the flow-mean virtual dipole moments (VDM) ranging from 3.6 to 6.2 ×10 22 A m 2. Our results, although not numerous, are of high technical quality and comparable to other paleointensity data recently obtained on younger lava flows. The NRM fractions used for paleointensity determination range from 38 to 79% and the quality factors vary between 4.8 and 16.7, being normally greater than 5. The combination of Baja California data with the available comparable quality Plio-Plesitocene paleointensity results yields a mean VDM of 6.3 ×10 22 A m 2, which is almost 80% of the present geomagnetic axial dipole. Reliable paleointensity results for the last 5 Ma are still scarce and of dissimilar quality, which makes it hard to draw any firm conclusions regarding the Pliocene and Early/Middle Pleistocene evolution of the geomagnetic field. To cite this article: J. Morales et al., C. R. Geoscience 335 (2003).

New potassium-argon basalt data in relation to the Pliocene Bluff Downs Local Fauna, northern Australia

International Nuclear Information System (INIS)

Mackness, B.S.

2000-01-01

A new radiometric date of 3.6 Ma for the basalt overlying fossiliferous units of the Allingham Formation, provides a minimum age for the Bluff Downs Local Fauna. Ground studies and interpretation of aerial photography has clarified the volcanic history of the area and a new basalt flow has been identified and named. Although the age of the capping basalt permits a younger age for the Bluff Downs Local Fauna than originally described, the stratigraphy, combined with the interpreted stage of evolution of the fauna, still supports an Early Pliocene age for the site. Copyright (2000) Geological Society of Australia

New Zealand's shallow-marine record of Pliocene-Pleistocene global sea-level and climate change

International Nuclear Information System (INIS)

Naish, T.R.

2005-01-01

It has now been 10 years since the first high resolution integrated studies of the Wanganui Basin glacio-eustatic cycles were published. During this time significant improvements have been made to the chronology and fine-scale stratigraphy of the basin fill. These improvements are a result of two main advances: (1) more detailed section (cycle) descriptions and mapping, constrained by new geochemically-characteristic tephra within the onshore basin, and (2) the use of onshore-offshore tephra correlations, which allow the highly resolved astrochronologies from the ODP 181 cores to be transferred onshore. In this issue we present the results from this latest phase of high resolution stratigraphic studies in the marine Pliocene-Pleistocene of New Zealand. (author). 45 refs., 2 figs

Sedimentary cycles and volcanic ash beds in the Lower Pliocene lacustrine succession of Ptolemais (NW Greece): discrepancy between 40 Ar/39 Ar and astronomical ages

NARCIS (Netherlands)

Steenbrink, J.; Vugt, N. van; Hilgen, F.J.; Wijbrans, J.R.; Meulenkamp, J.E.

1999-01-01

A high-resolution cyclostratigraphy for the rhythmically bedded lignite-marl sequences of the Lower Pliocene Ptole-mais Formation is combined with 40 Ar= 39 Ar dating results of intercalated volcanic ash beds. Detailed field reconnaissance in three open-pit lignite mines reveals three end-member

Relação anatômica do nervo supraescapular com o processo coracoide, articulação acromioclavicular e acrômio Anatomical relationship of the suprascapular nerve to the coracoid process, acromio clavicular joint and acromion

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Bernardo Barcellos Terra

2010-06-01

Full Text Available OBJETIVO: Estabelecer a relação anatômica do nervo supraescapular (NSE localizado na fossa supraescapular com a borda medial da base do coracoide, face articular acromial da articulação acromioclavicular e a borda anterolateral do acrômio. MÉTODOS: Foram dissecados 16 ombros de 16 cadáveres, sendo nove masculinos e sete femininos, mensurando com auxílio do paquímetro a distância do nervo supraescapular (na sua passagem sob o ligamento transverso com pontos fixos determinados na borda medial da base do processo coracoide, na face articular do acrômio da articulação acromioclavicular e na borda anterolateral do acrômio, correlacionando com a idade e o sexo. Foram excluídos cadáveres com intervenção cirúrgica prévia. RESULTADOS: Com relação à medida do nervo supraescapular, na sua fossa à borda medial da base do processo coracoide, obtivemos uma média de 3,9cm (variando de 3,1cm a 5,2cm; com relação à articulação acromioclavicular, a média foi de 4,7 (3,9cm a 5,2cm; e, com relação à borda anterolateral do acrômio, a média foi de 6,1cm (5,7cm a 6,8cm. CONCLUSÃO: É fundamental o conhecimento exato da anatomia dos nervos da região anterior do ombro para evitar lesões iatrogênicas e para conseguir resultados satisfatórios no tratamento cirúrgico das doenças do ombro, seja ele realizado de forma aberta ou artroscópica.OBJECTIVE: To establish the anatomic relationship of the suprascapular nerve (SSN located in the suprascapular notch to the medial border of the base of the coracoid process, the medial acromial surface of the acromioclavicular joint and the anterolateral edge of the acromion. METHODS: We dissected 16 shoulders of 16 cadavers, 9 males and 7 females. The distance from the suprascapular nerve (in its course beneath the transverse ligament to certain fixed points in the medial base of the coracoid process was measured with the aid of a caliper, as well as to the articular surface of the acromion

Sequence stratigraphy of the Nukumaruan stratotype (Pliocene-Pleistocene, c. 2.08-1.63 Ma), Wanganui Basin, New Zealand

International Nuclear Information System (INIS)

Abbott, S.T.; Naish, T.R.; Carter, R.M.; Pillans, B.J.

2005-01-01

Late Pliocene to Early Pleistocene (c. 2.08-1.63 Ma) strata exposed in coastal cliffs along Nukumaru and Ototoka beaches near Wanganui, between the top of the Nukumaru Limestone and the base of the Butlers Shell Conglomerate, comprise 11 depositional sequences of a total thickness of c. 86 m. The sequences consist predominantly of siliciclastic shoreline facies. Non-marine facies (including palaeosols), and a variety of shallow-marine shellbed facies, are also represented. Patterns in facies composition and sequence architecture reveal three sequence motifs (Maxwell, Nukumaru, and Birdgrove) that represent progressively increasing maximum palaeowater depths within a broadly basin-margin palaeogeographic setting. The sequence motif changes systematically up section and records a lower order tectonic influence on accommodation that has modulated the stacking patterns of individual sequences. Correlation of the sequences with oxygen isotope stages 77-57 is achieved using the basin-wide Ototoka tephra, and indicates that the sequences accumulated in response to obliquity driven (41 k.y. duration) glacio-eustatic sea-level oscillations. Correlation of the Nukumaru coast sequences with other sections along basin strike, and the global oxygen isotope record indicates that (i) 500 k.y. (δ 18 O stages MIS 56-34) is missing at the unconformity between the Nukumaruan and overlying Castlecliffian stratotypes on the Wanganui coast, and (ii) the Pliocene-Pleistocene boundary lies within sequence NC7 at the base of the Lower Maxwell Formation. (author). 52 refs., 15 figs., 2 tabs

Pliocene-Pleistocene (Nukumaruan) lithostratigraphy of the Tangoio block, and origin of sedimentary cyclicity, central Hawke's Bay, new Zealand

International Nuclear Information System (INIS)

Haywick, D.W.; Lowe, D.A.; Beu, A.G.; Henderson, R.A.; Carter, R.M.

1991-01-01

Eleven formations are defined within the Pliocene-Pleistocene Petane Group in a 450 km 2 uplifted area of central Hawkes Bay (Tangoio block). In ascending order these are: Waipunga Formation (new), Esk Formation, Tutira Formation (new), Aropaoanui Formation (new), Darkys Spur Formation (new), Mairau Formation (new), Tangoio Formation, Te Ngaru Formation, Waipatiki Formation, Devils Elbow Formation, and Kaiwaka Formation. Petane Group strata are cyclothemic and alternate between coarse-grained lithofacies (greywacke gravel, siliciclastic and carbonate sand/sandstone and bioclastic limestone) ascribed to nonmarine and inner shelf depositional environments, and sandy/muddy-silt ('papa') ascribed to mid-shelf deposition. The Petane Group is characterised by remarkable lateral continuity of formations, contrasting with conspicuous vertical changes. This stratigraphic style is consistent with glacio-eustatic sea-level fluctuations as proposed by Vella and Beu and Edwards, whereby coarse-grained lithofacies were deposited during sea-level low stands and fine-grained lithofacies were deposited during sea-level high stands. Foraminifera extracted from low-stand lithofacies display opposite δ 18 O signatures to that predicted for glacio-eustasy, a result of synsedimentary seawater dilution during sea-level low stands, and/or isotopic exchange during meteoric diagenesis. Stratigraphic and sedimentary criteria indicate that the Petane Group was deposited under unique circumstances of rapid basinal subsidence and a high rate of sedimentation. This offers an explanation for the general rarity of cyclothemic successions in the Pliocene-Pleistocene stratigraphic record. (author). 45 refs., 9 figs., 1 tab

Freshwater on the route of hominids "out of Africa" during the last interglacial revealed by U-Th in northern Red Sea fossil reefs

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Lazar, B.; Stein, M.; Agnon, A.; Shaked, Y.

2012-04-01

The migration of Anatomically Modern Hominids (AMH) "out of Africa" is a fundamental problem in the study of human culture concerning that the route passed through the presently hyperarid deserts surrounding the Red Sea. Here, we outline the evidence for significant presence of freshwater in a well developed phreatic coastal aquifer along the Red Sea shores during the last interglacial period. The fringing coral reefs were tectonically uplifted through the freshwater lens resulting in extensive recrystallization of reef framework from the primary aragonite into calcite. We developed a novel open-system U-Th dating methodology that enabled us estimating two ages for the calcitic reef terrace: 1. The original age of the reef terrace, deposited at ~190 ka BP; and 2. the time of freshwater recrystallization (from the primary aragonite into calcite) at ~140 ka BP. The age of freshwater recrystallization is consistent with other geological lines of evidence placing the time of AMH migration "out of Africa" at the onset of the last interglacial. It is likely therefore that during that time the hyperarid Red Sea area was wetter than today facilitating the migration of AMH to Europe and Asia.

Combined ESR/U-series chronology of Acheulian hominid-bearing layers at Trinchera Galeria site, Atapuerca, Spain

International Nuclear Information System (INIS)

Falgueres, Christophe; Bahain, Jean-Jacques; Shao, Qingfeng; Bischoff, James L.; Perez-Gonzalez, Alfredo; Ortega, Ana Isabel; Bermudez de Castro, Jose Maria; Olle, Andreu; Vallverdu, Josep; Quiles, Anita; Ghaleb, Bassam; Moreno, Davinia; Dolo, Jean-Michel; Vallverdu, Josep; Carbonell, Eudald; Arsuaga, Juan Luis

2013-01-01

The Sierra de Atapuerca, northern Spain, is known from many prehistoric and paleontologic sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galeria and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galeria archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galeria sites. The authors proposed for Galeria an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (≥530 ka) around 1 km away. In this paper, we present new results obtained by combined Electron Spin Resonance/Uranium-series (ESR/U-series) dating on 20 herbivorous teeth from different levels at the Galeria site. They are in agreement with the TL results for the upper part of the stratigraphic sequence (GIV and GIIIb), in the range of between 200 and 250 ka. But for the GIIIa to GIIb levels, the TL ages become abruptly older by 200 ka while ESR ages remain relatively constant. Finally, the TL and ESR data agree in the lowest part of the section (GIIa); both fall in the range of around 350-450 ka. Our results suggest a different interpretation for the GII, GIII and GIV units of Galeria and the upper part of Gran Dolina (TD10 and TD11) than obtained by TL. The ESR/U-series results are supported by a Bayesian analysis, which allows a better integration between stratigraphic information and radiometric data. (authors)

On the mechanisms of warming the mid-Pliocene and the inference of a hierarchy of climate sensitivities with relevance to the understanding of climate futures

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D. Chandan

2018-06-01

Full Text Available We present results from our investigation into the physical mechanisms through which the mid-Pliocene, with a pCO2 of only  ∼  400 ppmv, could have supported the same magnitude of global warmth as has been projected for the climate at the end of the 21st century when pCO2 is expected to be 3 times higher. These mechanisms allow us to understand the warming in terms of changes to the radiative properties of the surface, the clouds, greenhouse gases, and changes to the meridional heat transport. We find that two-thirds of the warming pervasive during the mid-Pliocene, compared to the preindustrial, could be attributed to the reduction in the planetary emissivity owing to the higher concentrations of the greenhouse gases CO2 and water vapor, and the remaining one-third to the reduction in planetary albedo. We also find that changes to the orography and the pCO2 are the leading causes of the warming with each contributing in roughly equal parts to a total of 87 % of the warming and changes to the polar ice sheets responsible for the remaining warming. Furthermore, we provide a mid-Pliocene perspective on ongoing efforts to understand the climate system's sensitivity at various timescales and using multiple lines of evidence. The similarities in the boundary conditions between the mid-Pliocene and the present day, together with the globally elevated temperatures, make the mid-Pliocene an ideal paleo time period from which to derive inferences of climate sensitivity and assess the impacts of various timescale-dependent feedback processes. We assess a hierarchy of climate sensitivities of increasing complexity in order to explore the response of the climate over a very large range of timescales. The picture that emerges is as follows: on the short timescale, owing to the influence of fast feedback processes, the climate sensitivity is 3.25 °C per doubling of CO2; sensitivity increases to 4.16 °C per doubling of CO2 on an intermediate

Vegetation Response to Upper Pliocene Glacial/Interglacial Cyclicity in the Central Mediterranean

Science.gov (United States)

Combourieu-Nebout, Nathalie

1993-09-01

New detailed pollen analysis of the lower part of the Upper Pliocene Semaforo section (Crotone, Italy) documents cyclic behavior of vegetation at the beginning of the Northern Hemisphere glaciations. The competition between four vegetation units (subtropical humid forest, deciduous temperate forest, altitudinal coniferous forest, and open xeric assemblage) probably reflects modifications of vegetation belts at this montane site. Several increases in herbaceous open vegetation regularly alternate with subtropical humid forest, which expresses rapid climatic oscillations. The complete temporal succession—deciduous forest (rich in Quercus), followed by subtropical humid forest (Taxodiaceae and Cathaya), then altitudinal coniferous forest ( Tsuga, Cedrus, Abies, and Picea), and finally herbaceous open vegetation (Graminae, Compositae, and Artemisia )—displays the climatic evolution from warm and humid interglaciation to cold and dry glaciation. It also suggests an independent variation of temperature and humidity, the two main climatic parameters. The vegetation history of southern Calabria recorded in the Semaforo section have been correlated with the ∂ 18O signal established in the Atlantic Ocean.

A reassessment of the study of cut mark patterns to infer hominid manipulation of fleshed carcasses at the Flk Zinj 22 site, Olduvai Gorge, Tanzania

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Domínguez-Rodrigo, Manuel

1997-12-01

Full Text Available Previous experimental studies on cut marks have suggested that cut mark percentages and their anatomical distribution (based on element type and bone section type could be used to differentiate primary access to fleshed carcasses from secondary access to defleshed carcasses. In this study, the experimental sample of this type of studies is increased and further data are included to infer a primary access by hominids to carcasses at the FLK Zinj site of Olduvai.

Estudios experimentales anteriores sobre marcas de corte han sugerido que los porcentajes de marcas de corte y su distribución (basada en tipo de hueso y tipo de sección ósea podrían usarse para diferenciar un acceso primario a carcasas con carne de un acceso secundario a carcasas descarnadas. En este estudio semejante muestra experimental se ve ampliada y se muestran más datos que sirven para inferir que los homínidos tuvieron un acceso primario a las carcasas representadas en el yacimiento FLK Zinj de Olduvai.

High-resolution U-series dates from the Sima de los Huesos hominids yields 600 +∞-66: implications for the evolution of the early Neanderthal lineage

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Bischoff, James L.; Williams, Ross W.; Rosenbauer, Robert J.; Aramburu, Arantza; Arsuaga, Juan Luis; Garcia, Nuria; Cuenca-Bescos, Gloria

2007-01-01

The Sima de los Huesos site of the Atapuerca complex near Burgos, Spain contains the skeletal remains of at least 28 individuals in a mud-breccia underlying an accumulation of the Middle Pleistocene cave bear (Ursus deningeri). We report here on new high-precision dates on the recently discovered speleothem SRA-3 overlaying human bones within the Sima de los Huesos. Earlier analyses of this speleothem by TIMS (thermal-ionization mass-spectrometry) showed the lower part to be indistinguishable from internal isotopic equilibrium at the precision of the TIMS instrumentation used, yielding minimum age of 350 kyr (kyr = 103 yr before present). Reanalysis of six samples of SRA-3 by inductively-coupled plasma-multicollector mass-spectrometry (ICP-MS) produced high-precision analytical results allowing calculation of finite dates. The new dates cluster around 600 kyr. A conservative conclusion takes the lower error limit ages as the minimum age of the speleothem, or 530 kyr. This places the SH hominids at the very beginnings of the Neandertal evolutionary lineage.

Pliocene episodic exhumation and the significance of the Munsiari thrust in the northwestern Himalaya

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Stübner, Konstanze; Grujic, Djordje; Dunkl, István; Thiede, Rasmus; Eugster, Patricia

2018-01-01

The Himalayan thrust belt comprises three in-sequence foreland-propagating orogen-scale faults, the Main Central thrust, the Main Boundary thrust, and the Main Frontal thrust. Recently, the Munsiari-Ramgarh-Shumar thrust system has been recognized as an additional, potentially orogen-scale shear zone in the proximal footwall of the Main Central thrust. The timing of the Munsiari, Ramgarh, and Shumar thrusts and their role in Himalayan tectonics are disputed. We present 31 new zircon (U-Th)/He ages from a profile across the central Himachal Himalaya in the Beas River area. Within a ∼40 km wide belt northeast of the Kullu-Larji-Rampur window, ages ranging from 2.4 ± 0.4 Ma to 5.4 ± 0.9 Ma constrain a distinct episode of rapid Pliocene to Present exhumation; north and south of this belt, zircon (U-Th)/He ages are older (7.0 ± 0.7 Ma to 42.2 ± 2.1 Ma). We attribute the Pliocene rapid exhumation episode to basal accretion to the Himalayan thrust belt and duplex formation in the Lesser Himalayan sequence including initiation of the Munsiari thrust. Pecube thermokinematic modelling suggests exhumation rates of ∼2-3 mm/yr from 4-7 to 0 Ma above the duplex contrasting with lower (middle-late Miocene exhumation rates. The Munsiari thrust terminates laterally in central Himachal Pradesh. In the NW Indian Himalaya, the Main Central thrust zone comprises the sheared basal sections of the Greater Himalayan sequence and the mylonitic 'Bajaura nappe' of Lesser Himalayan affinity. We correlate the Bajaura unit with the Ramgarh thrust sheet in Nepal based on similar lithologies and the middle Miocene age of deformation. The Munsiari thrust in the central Himachal Himalaya is several Myr younger than deformation in the Bajaura and Ramgarh thrust sheets. Our results illustrate the complex and segmented nature of the Munsiari-Ramgarh-Shumar thrust system.

Southern San Andreas Fault Slip History Refined Using Pliocene Colorado River Deposits in the Western Salton Trough

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Dorsey, R. J.; Bennett, S. E. K.; Housen, B. A.

2016-12-01

Tectonic reconstructions of Pacific-North America plate motion in the Salton Trough region (Bennett et al., 2016) are constrained by: (1) late Miocene volcanic rocks that record 255 +/-10 km of transform offset across the northern Gulf of California since 6 Ma (average 42 mm/yr; Oskin and Stock, 2003); and (2) GPS data that show modern rates of 50-52 mm/yr between Pacific and North America plates, and 46-48 mm/yr between Baja California (BC) and North America (NAM) (Plattner et al., 2007). New data from Pliocene Colorado River deposits in the Salton Trough provide an important additional constraint on the geologic history of slip on the southern San Andreas Fault (SAF). The Arroyo Diablo Formation (ADF) in the San Felipe Hills SW of the Salton Sea contains abundant cross-bedded channel sandstones deformed in the dextral Clark fault zone. The ADF ranges in age from 4.3 to 2.8 Ma in the Fish Creek-Vallecito basin, and in the Borrego Badlands its upper contact with the Borrego Formation is 2.9 Ma based on our new magnetostratigraphy. ADF paleocurrent data from a 20-km wide, NW-oriented belt near Salton City record overall transport to the SW (corrected for bedding dip, N=165), with directions ranging from NW to SE. Spatial domain analysis reveals radial divergence of paleoflow to the: W and NW in the NW domain; SW in the central domain; and S in the SE domain. Data near Borrego Sink, which restores to south of Salton City after removing offset on the San Jacinto fault zone, show overall transport to the SE. Pliocene patterns of radial paleoflow divergence strongly resemble downstream bifurcation of fluvial distributary channels on the modern Colorado River delta SW of Yuma, and indicate that Salton City has translated 120-130 km NW along the SAF since 3 Ma. We propose a model in which post-6 Ma BC-NAM relative motion gradually accelerated to 50 mm/yr by 4 Ma, continued at 50 mm/yr from 4-1 Ma, and decreased to 46 mm/yr from 1-0 Ma (split equally between the SAF and

Reescrituras divulgativas del mito cidiano. Descripción y análisis de adaptaciones y versiones contemporáneas representativas del Cantar de Mio Cid.

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Aldo Daparte Jorge

2014-12-01

Full Text Available Las polémicas adaptaciones de los clásicos al servicio de los mediadores en la enseñanza literaria o de la divulgación de obras canónicas han generado una literatura en segundo grado marcada por ricas relaciones hipertextuales (Genette. El objetivo de este trabajo es dar una visión panorámica de los elementos textuales y paratextuales implicados en una selección representativa de adaptaciones de la materia cidiana, preferentemente gestadas con intención didáctica, debidamente contextualizadas en la tradición de adaptaciones del Cantar de Mio Cid. Dicho análisis permite comprobar los rasgos específicos que caracterizan este proceso, sustancialmente distinto al seguido en la reescritura de otras obras del canon español, debido a factores como las fuentes histórico-legendarias y literarias de la materia argumental, la forma del relato o su performance.

Endothelin B Receptors on Primary Chicken Müller Cells and the Human MIO-M1 Müller Cell Line Activate ERK Signaling via Transactivation of Epidermal Growth Factor Receptors.

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Mohammad Harun-Or-Rashid

Full Text Available Injury to the eye or retina triggers Müller cells, the major glia cell of the retina, to dedifferentiate and proliferate. In some species they attain retinal progenitor properties and have the capacity to generate new neurons. The epidermal growth factor receptor (EGFR system and extracellular signal-regulated kinase (ERK signaling are key regulators of these processes in Müller cells. The extracellular signals that modulate and control these processes are not fully understood. In this work we studied whether endothelin receptor signaling can activate EGFR and ERK signaling in Müller cells. Endothelin expression is robustly upregulated at retinal injury and endothelin receptors have been shown to transactivate EGFRs in other cell types. We analyzed the endothelin signaling system in chicken retina and cultured primary chicken Müller cells as well as the human Müller cell line MIO-M1. The Müller cells were stimulated with receptor agonists and treated with specific blockers to key enzymes in the signaling pathway or with siRNAs. We focused on endothelin receptor mediated transactivation of EGFRs by using western blot analysis, quantitative reverse transcriptase PCR and immunocytochemistry. The results showed that chicken Müller cells and the human Müller cell line MIO-M1 express endothelin receptor B. Stimulation by the endothelin receptor B agonist IRL1620 triggered phosphorylation of ERK1/2 and autophosphorylation of (Y1173 EGFR. The effects could be blocked by Src-kinase inhibitors (PP1, PP2, EGFR-inhibitor (AG1478, EGFR-siRNA and by inhibitors to extracellular matrix metalloproteinases (GM6001, consistent with a Src-kinase mediated endothelin receptor response that engage ligand-dependent and ligand-independent EGFR activation. Our data suggest a mechanism for how injury-induced endothelins, produced in the retina, may modulate the Müller cell responses by Src-mediated transactivation of EGFRs. The data give support to a view in

Qualidade da carne de frangos de corte submetidos a dietas suplementadas com crômio, criados em diferentes temperaturas ambientais - DOI: 10.4025/actascianimsci.v29i2.218 Meat quality of broiler chicks submeted the supplemented diets with chromium and reared in differents enviromental temperatures - DOI: 10.4025/actascianimsci.v29i2.218

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Nívea Maria Brancaci Zeoula

2007-11-01

Full Text Available Foram realizados dois experimentos. O experimento um objetivou avaliar a composição da carne do peito de frangos alimentados com dietas suplementadas com crômio (0, 400, 800 e 1.200 μg Cr kg-1 complexado a levedura, criados sob diferentes condições de temperatura (quente, termoneutra e fria. O experimento dois objetivou avaliar a qualidade da carne do peito de frangos alimentados com dietas suplementadas com crômio (0 e 400 μg Cr kg-1, criados nas mesmas condições do experimento um e desossados em diferentes períodos (0, 5 e 24 horas. Os resultados mostram que as aves criadas em ambiente frio apresentaram a carne com menor porcentagem de matéria mineral e crômio e maior intensidade de vermelho, enquanto as aves criadas em temperatura termoneutra apresentaram carne com menor porcentagem de umidade, e as aves criadas em temperatura quente, carne com maior luminosidade. Já a suplementação de crômio não proporcionou qualquer efeito na composição e na qualidade de carne, enquanto que o aumento no período de desossa proporcionou um menor comprimento de sarcômero, força de cisalhamento e intensidade de amarelo, porém uma maior luminosidade.Two experiments were conducted being the objective of the first experiment to evaluate the the composition of breast meat of broiler chicks fed with diets supplemented with chromium yeast (0; 400; 800 and 1,200 μg Cr kg-1 reared in different environmental temperatures (hot, thermoneutral and cold. The second experiment aimed to evaluate the quality of breast meat of broiler chicks fed with diets supplemented with chromium yeast (0 and 400 μg Cr kg-1, reared in different environmental temperatures (hot, thermoneutral and cold and deboned in different periods (0, 5 and 24 hours. The results showed that birds reared in cold environmental temperature showed meat with lower mineral matter percentage and chromium and higher values of redness, whereas the birds reared in thermoneutral environment

Paleosoils and pedogenic calcretes formations in Fray Bentos (Oligocene - early miocene) Raigon (late pliocene and middle pleistocene) and Libertad (early - middle pleistocene)

International Nuclear Information System (INIS)

Tofalo, O.; Morras, H.; Sanchez-Bettucci, L.

2012-01-01

The Fray Bentos formation is composed by loessic deposits based on paleosoils and pedogenic calcretes (Oligocene - early miocene). In this deposits are tubular and lamellar formations which would have been formed in arid climates.The fluvial origen of Raigon Formation, (late pliocene and middle pleistocene) presents a paleosoil roof which is generated under a subhumid climate.The Libertad Formation during the glacial intervals consisted of loess deposits

The gold nuggets of the lower Pliocene Alhambra Formation (Betic Cordillera, Southern Spain)

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Somma, Roberta; Bonvegna, Piero; Sanchez-Navas, Antonio

2017-04-01

The present research was devoted to the geochemical and textural characterization of gold nuggets extracted from auriferous siliciclastic deposits of the lower Pliocene continental Alhambra Formation (Betic Cordillera, Southern Spain). This Formation is mainly composed of metamorphic lithoclasts deriving both by the erosion of the Mulhacen Unit of the Nevado-Filabride Complex and the reworking of the upper Tortonian marine Dudar-Pinos Genil Formation, on its turn previously formed by erosion of the Veleta Unit of the Nevado-Filabride Complex. Particularly, the studied gold nuggets were separated from 1m3 of auriferous conglomerates sampled along the right side of the Genil River, in the abandoned Lancha de Cenes Mine, exploited since Roman time for gold mining. The recovered gold nuggets were 24 for a total weight of 0.125 g/m3. Textural analysis of gold nuggets was made by means mechanical sieving and visual comparison of roundness and form. They are sand-sized rounded to sub-rounded grains with spheroidal and cubic form. Surface analyses of the nuggets by SEM-EDS indicated that external portions show textures more porous than in the nuggets nuclei. Chemical analyses by EMPA indicated that they are constituted by pure gold with Ag and Hg as trace elements. The gold mine capacity of the studied auriferous deposits is at least of 0.125 g/m3 (lower than 0.5 g/m3; minimum value to be gold mine economically exploitable). Notwithstanding this value, the auriferous conglomerates of the Alhambra Formation reveal to be interesting under a gold mine exploitation point of view because of the gold high pureness degree. Finally, under a geological point of view, considering that the Alhambra Formation is mainly composed of lower Pliocene alluvial fan conglomerates and sandstones formed during the uplift of the Sierra Nevada, the selected gold nuggets are secondary deposits originally derived from primary deposits related to hydrothermal gold-bearing quartz veins included in

Aminostratigraphic correlations and paleotemperature implications, Pliocene-Pleistocene high-sea-level deposits, northwestern Alaska

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Kaufman, Darrell S.; Brigham-Grette, Julie

Multiple periods of Late Pliocene and Pleistocene high sea level are recorded by surficial deposits along the coastal plains of northwestern Alaska. Analyses of the extent of amino acid epimerization in fossil molluscan shells from the Nome coastal plain of the northern Bering Sea coast, and from the Alaskan Arctic Coastal Plain of the Chukchi and Beaufort Sea coasts, allow recognition of at least five intervals of higher-than-present relative sea level. Three Late Pliocene transgressions are represented at Nome by the complex and protracted Beringian transgression, and on the Arctic Coastal Plain by the Colvillian, Bigbendian, and Fishcreekian transgressions. These were followed by a lengthy period of non-marine deposition during the Early Pleistocene when sea level did not reach above its present position. A Middle Pleistocene high-sea-level event is represented at Nome by the Anvilian transgression, and on the Arctic Coastal Plain by the Wainwrightian transgression. Anvilian deposits at the type locality are considerably younger than previously thought, perhaps as young as Oxygen-Isotope Stage 11 (˜410,000 BP). Finally, the last interglacial Pelukian transgression is represented discontinuously along the shores of northwestern Alaska. Amino acid epimerization data, together with previous paleomagnetic measurements, radiometric-age determinations, and paleontologic evidence provide geochronological constraints on the sequence of marine deposits. They form the basis of regional correlations and offer a means of evaluating the post-depositional thermal history of the high-sea-level deposits. Provisional correlations between marine units at Nome and the Artic Coastal Plain indicate that the temperature difference that separates the two sites today had existed by about 3.0 Ma. Since that time, the effective diagenetic temperature was lowered by about 3-4°C at both sites, and the mean annual temperature was lowered considerably more. This temperature decrease was

An initial examination of carbonate production in the western equatorial Pacific: XRF results from the Pliocene-Pleistocene of IODP Site U1490

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Chapman, J.; Kulhanek, D. K.; Rosenthal, Y.; Holbourn, A. E.

2017-12-01

International Ocean Discovery Program (IODP) Expedition 363 sought to determine the nature of and driving forces behind climate variability in the Western Pacific Warm Pool (WPWP) region throughout the Neogene on millennial, orbital, and geologic timescales. Our research focuses on the Pliocene to recent (4-0 Ma) sediment record from IODP Site U1490 to examine changes in carbonate production and burial in the WPWP as a record of variations in the regional/global carbon cycle. This interval is of particular interest because it spans the Middle Pliocene Warm Period, the initiation of Northern Hemisphere Glaciation, and the Mid-Pleistocene Transition. Site U1490 is located on the northern edge of Eauripik Rise at 05°58.95'N, 142°39.27'E in the northern part of the WPWP. At 2341 m water depth, today the site is bathed in Upper Circumpolar Deepwater. Pliocene to recent sediment primarily consists of foraminifer-rich nannofossil ooze, with the sedimentation rate varying between 1.5 and 3 cm/kyr. Initial shipboard measurement of calcium carbonate content shows little variation at low resolution (1 sample every few meters), varying between 90 and 95 wt%. We collected X-ray fluorescence (XRF) data at 2 cm resolution along the composite stratigraphic section to obtain a qualitative measure of the bulk chemistry of the sediment. We will use the weight percent calcium carbonate of discrete samples to calibrate the XRF data to generate a high-resolution carbonate record. We observe cyclical variations in the Ca/Ba, which may reflect variations in productivity and/or dissolution through this interval, although additional work is needed to fully interpret these data. Ultimately our research will allow for comparison between records obtained from these cores located in the western equatorial Pacific to those obtained in the eastern and central Pacific, which will better elucidate the nature of the carbon system during the Plio-Pleistocene.

Extreme diagenesis displayed by Pliocene-Pleistocene Calcareous Nannofossils in IODP Hole 1396A, adjacent to Montserrat Island in the Lesser Antilles

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Aljahdali, M. H.; Behzad, A.; Missimer, T. M.; Wise, S. W.; Scientists, E.

2013-12-01

Adjacent to Montserrat Island in the Lesser Antilles of the Caribbean Sea, Integrated Ocean Drilling Program (IODP) Site 1396 recovered lower Pliocene to Pleistocene calcareous nannofossil assemblages (CN11 to CN15) that range between common to abundant and display a variety of preservations. High-resolution Scanning Electron Microscopy (SEM) observation of calcareous nannofossil assemblages in selected samples from Hole 1396A, shows severe diagenesis (overgrowth and/or dissolution) even near the top of the sequence. The nannofossil assemblages in this relatively shallow basin (e.g., 800 m) reveal abnormal diagenesis for such young specimens that are quite similar to the heavy overgrowths and dissolution generally seen only in older deposits (e.g., Cretaceous). Our hypothesis is that volcanic activity in the region probably induced this extreme diagenesis. A more detailed examination of these samples should provide a better understanding of the progression of carbonate diagenesis in this basin. The nannofossil biostratigraphy and magnetostratigraphy at Site 1396 also suggest lower sedimentation rates in the Pleistocene than in the Pliocene. A comparison site (ODP Leg 165 Site 1000) in the Caribbean Sea also shows a similar sedimentation-rate pattern. This we interpret as a regional event caused by the closure of the Central American Seaway.

Late Miocene-Early Pliocene reactivation of the Main Boundary Thrust: Evidence from the seismites in southeastern Kumaun Himalaya, India

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Mishra, Anurag; Srivastava, Deepak C.; Shah, Jyoti

2013-05-01

Tectonic history of the Himalaya is punctuated by successive development of the faults that run along the boundaries between different lithotectonic terrains. The Main Boundary Fault, defining the southern limit of the Lesser Himalayan terrain, is tectonically most active. A review of published literature reveals that the nature and age of reactivation events on the Main Boundary Fault is one of the poorly understood aspects of the Himalayan orogen. By systematic outcrop mapping of the seismites, this study identifies a Late Miocene-Early Pliocene reactivation on the Main Boundary Thrust in southeast Kumaun Himalaya. Relatively friable and cohesionless Neogene sedimentary sequences host abundant soft-sediment deformation structures in the vicinity of the Main Boundary Thrust. Among a large variety of structures, deformed cross-beds, liquefaction pockets, slump folds, convolute laminations, sand dykes, mushroom structures, fluid escape structures, flame and load structures and synsedimentary faults are common. The morphological attributes, the structural association and the distribution pattern of the soft-sediment deformation structures with respect to the Main Boundary Fault strongly suggest their development by seismically triggered liquefaction and fluidization. Available magnetostratigraphic age data imply that the seismites were developed during a Late Miocene-Early Pliocene slip on the Main Boundary Thrust. The hypocenter of the main seismic event may lie on the Main Boundary Thrust or to the north of the study area on an unknown fault or the Basal Detachment Thrust.

Associação clínico-radiográfica do índice acromial e do ângulo de inclinação lateral do acrômio Association clinical-radiographic of the acromion índex and the lateral acromion angle

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Flavio Amado Hanciau

2012-01-01

Full Text Available OBJETIVO: Avaliar o perfil clínico-radiográfico correlacionando sintomatologia de doença subacromial com adaptação da medida do ângulo de inclinação lateral do acrômio para uma mensuração radiográfica e seu respectivo índice acromial. MÉTODOS: No período de outubro de 2010 a fevereiro de 2011 foram avaliados 55 ombros dolorosos, com teste de Neer e radiografia em anteroposterior verdadeiro. Os pacientes foram divididos em dois grupos, com teste de Neer positivo e negativo. A aferição do índice acromial e do ângulo de inclinação lateral do acrômio foi padronizada e comparada através de médias estatísticas em 0,7 e 75º, respectivamente. RESULTADOS: Houve predomínio na população sintomática, do sexo feminino (72,73%, idade menor que 59 anos (62,5% e lado dominante (65,31%. O índice acromial acima de 0,7 mostrou-se sintomático em 66,67% e a inclinação lateral do acrômio menor que 75º em 82,61%. Quando associados os métodos, 62,5% apresentavam clínica positiva (p OBJECTIVE: To evaluate the clinical-radiographic subacromial disease symptoms correlated with adaptation of the measure of lateral acromion angle and its respective measuring ra diographic acromial index. METHODS: In the period between october 2010 and february 2011 were evaluated 55 painful shoulders with Neer test and true anteroposterior radiogra phy. Patients were divided into two groups, with Neer test positive and negative. The index measuring the acromion and the lateral acromion angle have been standardized, and compared using statistical averages of 0.7 and 75º, respec tively. RESULTS: The predominant symptom in the population, females (72.73%, age less than 59 years (62.5% and domi nant side (65.31%. The acromion index above 0.7 was found to be symptomatic in 66.67% and lateral acromion angle less than 75 º in 82.61%. When associated methods, 62.5% had positive clinical (p<0.083. CONCLUSION: The determination of radiographic acromial index

Late cenozoic magmatism in the South Patagonian batholith: SHRIMP U-Pb zircon age evidence

International Nuclear Information System (INIS)

Fanning, C.M; Herve, F; Pankhurst, R.J; Thomson, S; Faundez, V

2001-01-01

The North Patagonian Batholith (NPB) has a zonal age pattern which includes a well defined belt of Miocene and Mio-Pliocene plutons in its central portion (Pankhurst et al., 1999) which are spatially, and probably genetically related to the Liquine-Ofqui Fault Zone. Previous geochronological studies in the Southern Patagonian Batholith (SPB), as summarized by Bruce et al. (1991), have yielded 9 late Cenozoic K-Ar or Ar-Ar ages out of a total of 116 age determinations. None of these young ages correspond to U-Pb determinations on zircons, and some of the young ages correspond to satellite plutons east of the SPB proper, such as the Torres del Paine intrusion. In this paper we present the first late Cenozoic SHRIMP U-Pb zircon ages in the area of the SPB. The morphology of the analysed zircon crystals is described and leads to some inferences on the methodology and on the geological interpretation of the obtained ages (au)

Geology of Isla de Mona, Puerto Rico

Science.gov (United States)

Frank, E.F.; Wicks, Carol M.; Mylroie, J.; Troester, J.; Alexander, E.C.; Carew, J.L.

1998-01-01

Isla de Mona is a carbonate island located in the Mona Passage 68 km west of Puerto Rico. The tectonically uplifted island is 12 km by 5 km, with an area of 55 km2, and forms a raised flat-topped platform or meseta. The meseta tilts gently to the south and is bounded by near vertical cliffs on all sides. These cliffs rise from 80 m above sea level on the north to 20 m above the sea on the southern coast. Along the southwestern and western side of the island a three- to six-meter-high Pleistocene fossil reef abuts the base of the cliff to form a narrow coastal plain. The meseta itself consists of two Mio-Pliocene carbonate units, the lower Isla de Mona Dolomite and the upper Lirio Limestone. Numerous karst features, including a series of flank margin caves primarily developed at the Lirio Limestone/Isla de Mona Dolomite contact, literally ring the periphery of the island.

The presence of Ursus ex gr. minimus-thibetanus in the late villányian and its position among the Pliocene and Pleistocene black bears in Europe

Czech Academy of Sciences Publication Activity Database

Wagner, Jan; Čermák, Stanislav; Horáček, I.

-, č. 4 (2011), s. 39-58 ISSN 1771-1150 R&D Projects: GA ČR GA205/09/0184 Institutional research plan: CEZ:AV0Z30130516 Keywords : Black bear * MN17 * Ursus aff. thibetanus * Villány 3 * Central Europe - Hungary * Ursus * Pleistocene * Pliocene Subject RIV: DB - Geology ; Mineralogy

AUTOCHTHONOUS BIOFACIES IN THE PLIOCENE LORETO BASIN, BAJA CALIFORNIA SUR, MEXICO

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MICHELE PIAZZA

1998-07-01

Full Text Available The present paper examines the molluscan and/or echinoid assemblages recovered from two lithostratigraphic units (Piedras Rodadas Sandstone and Arroyo de Arce Norte Sandstone outcropping in the Pliocene Loreto Basin, Baja California Sur, Mexico. Ten biofacies have been identified, i.e. Trachycardium procerum-Trachycardium senticosum Biofacies, Chione compta-Transennella modesta Biofacies, Laevicardium elenense-Chione kelletii Biofacies, Xenophora sp. 1-Strombus subgracilior Biofacies, Crassostrea californica osunai Biofacies, Myrakeena angelica Biofacies, Vermetid-Nodipecten Biofacies, Argopecten abietis abietis Biofacies, Aequipecten dallasi Biofacies and Encope Biofacies. The first four biofacies have been defined on the basis of statistical analyses (cluster analysis, MDS. The other six, which are monospecific or definitely low-diversity, were already identified during field work. The deduced paleoecological bearing of biofacies, largely relying upon the comparison to their closest modern counterparts, provides the basis for the paleoenvironmental reconstruction. The latter also considers sedimentological evidence and is framed within the tectonic and sedimentary context recently proposed by American workers. Biofacies point toward environments differing in terms of substrate texture, presence/absence of vegetal cover, energy level, variously distributed within the low tide mark-40 m bathymetric range. 

Foraminifera Models to Interrogate Ostensible Proxy-Model Discrepancies During Late Pliocene

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Jacobs, P.; Dowsett, H. J.; de Mutsert, K.

2017-12-01

Planktic foraminifera faunal assemblages have been used in the reconstruction of past oceanic states (e.g. the Last Glacial Maximum, the mid-Piacenzian Warm Period). However these reconstruction efforts have typically relied on inverse modeling using transfer functions or the modern analog technique, which by design seek to translate foraminifera into one or two target oceanic variables, primarily sea surface temperature (SST). These reconstructed SST data have then been used to test the performance of climate models, and discrepancies have been attributed to shortcomings in climate model processes and/or boundary conditions. More recently forward proxy models or proxy system models have been used to leverage the multivariate nature of proxy relationships to their environment, and to "bring models into proxy space". Here we construct ecological models of key planktic foraminifera taxa, calibrated and validated with World Ocean Atlas (WO13) oceanographic data. Multiple modeling methods (e.g. multilayer perceptron neural networks, Mahalanobis distance, logistic regression, and maximum entropy) are investigated to ensure robust results. The resulting models are then driven by a Late Pliocene climate model simulation with biogeochemical as well as temperature variables. Similarities and differences with previous model-proxy comparisons (e.g. PlioMIP) are discussed.

Pliocene –Pleistocene geomorphological evolution of the Adriatic side of Central Italy

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Gentili Bernardino

2017-02-01

Full Text Available This work is a significant contribution to knowledge of the Quaternary and pre-Quaternary morphogenesis of a wide sector of central Italy, from the Apennine chain to the Adriatic Sea. The goal is achieved through a careful analysis and interpretation of stratigraphic and tectonic data relating to marine and continental sediments and, mostly, through the study of relict limbs of ancient landscapes (erosional surfaces shaped by prevailing planation processes. The most important scientific datum is the definition of the time span in which the modelling of the oldest morphological element (the “summit relict surface” occurred: it started during Messinian in the westernmost portion and after a significant phase during middle-late Pliocene, ended in the early Pleistocene. During the middle and late Pleistocene, the rapid tectonic uplift of the area and the climate fluctuations favoured the deepening of the hydrographic network and the genesis of three orders of fluvial terraces, thus completing the fundamental features of the landscape. The subsequent Holocene evolution reshaped the minor elements, but not the basic ones.

Late Pliocene establishment of exorheic drainage in the northeastern Tibetan Plateau as evidenced by the Wuquan Formation in the Lanzhou Basin

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Guo, Benhong; Liu, Shanpin; Peng, Tingjiang; Ma, Zhenhua; Feng, Zhantao; Li, Meng; Li, Xiaomiao; Li, Jijun; Song, Chunhui; Zhao, Zhijun; Pan, Baotian; Stockli, Daniel F.; Nie, Junsheng

2018-02-01

The fluvial archives in the upper-reach Yellow River basins provide important information about drainage history of the northeastern Tibetan Plateau (TP) associated with geomorphologic evolution and climate change. However, the Pliocene fluvial strata within this region have not been studied in detail, hence limiting the understanding of the late Cenozoic development of regional fluvial systems. In this paper, we present the results of a study of the geochronology, sedimentology, and provenance of the fluvial sequence of the Wuquan Formation in the Lanzhou Basin in the northeastern TP. Magnetostratigraphic and cosmogenic nuclide burial ages indicate that the Wuquan Formation was deposited during 3.6-2.2 Ma. Furthermore, sedimentary facies, gravel composition, paleocurrent data, and detrital zircon Usbnd Pb age spectra reveal that the fluvial sequence resembles the terraces of the Yellow River in terms of source area, flow direction, and depositional environment. Our results indicate that a paleo-drainage system flowing out of the northeastern TP was established by ca. 3.6 Ma and that the upstream parts of the Yellow River must have developed subsequently from this paleo-drainage system. The late Pliocene drainage system fits well with the dramatic uplift of the northeastern TP, an intensified Asian summer monsoon, and global increase in erosion rates, which may reflect interactions between geomorphic evolution, tectonic deformation, and climate change.

Sensitivity of Pliocene Arctic climate to orbital forcing, atmospheric CO2 and sea ice albedo parameterisation

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Howell, Fergus W.; Haywood, Alan M.; Dowsett, Harry J.; Pickering, Steven J.

2016-01-01

General circulation model (GCM) simulations of the mid-Pliocene Warm Period (mPWP, 3.264 to 3.025 Myr ago) do not reproduce the magnitude of Northern Hemisphere high latitude surface air and sea surface temperature (SAT and SST) warming that proxy data indicate. There is also large uncertainty regarding the state of sea ice cover in the mPWP. Evidence for both perennial and seasonal mPWP Arctic sea ice is found through analyses of marine sediments, whilst in a multi-model ensemble of mPWP climate simulations, half of the ensemble simulated ice-free summer Arctic conditions. Given the strong influence that sea ice exerts on high latitude temperatures, an understanding of the nature of mPWP Arctic sea ice would be highly beneficial.

Calcareous nannoplankton assemblages across the Pliocene-Pleistocene transition in the southwestern Indian Ocean, IODP Site U1475

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Cares, Z.; Farr, C. L.; LeVay, L.; Tangunan, D.; Brentegani, L.

2017-12-01

International Ocean Discovery Program (IODP) Expedition 361 cored six sites along the greater Agulhas Current System to track its intensity through time and to better understand its role in global oceanic circulation and climate. One of the main scientific objectives of this expedition was to determine the dynamics of the Indian-Atlantic Ocean Gateway circulation during Pliocene-Pleistocene climate changes in association with changing wind fields and migrating ocean fronts. The Indian-Atlantic Ocean Gateway contains a pronounced oceanic frontal system, the position of which has the potential to influence global climate on millennial scales. Owing to the physical differences between the frontal zones, this region has complex biogeochemistry, changes in phytoplankton distribution, and variations in primary productivity. Site U1475 was cored on the Agulhas Plateau in the Southwestern Indian Ocean and recovered a complete sequence of calcareous ooze spanning the last 7 Ma. Previous studies at this locality have shown latitudinal migrations of the frontal zones over the past 350 kyr that resulted in prominent millennial shifts in primary production, biological pump efficiency, and microfossil assemblages that coincide with Antarctic climate variability. Here we present initial results comprised of calcareous nannoplankton assemblages in order to test if similar latitudinal frontal migrations occurred during the Pliocene-Pleistocene transition (PPT; 2.7 Ma). The calcareous nannoplankton assemblage shows an abundance increase of taxa associated with cooler water and higher primary production across the PPT interval. In addition to a change in species abudance, the Shannon diversity index drops notably across the transition, which is typical of nannoplankton communities in more productive regions. These data suggest that a long-term change in sea surface temperature and nutrient availability took place across the PPT, potentially linked to the northward migration of

Marine Isotope Stage (MIS) M2 ( 3.3 Ma) in the southern hemisphere: constraining the climatic drivers of a short-term glaciation event during the Pliocene warm Period.

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De Vleeschouwer, D.; Auer, G.; Bogus, K.; Groeneveld, J.; Henderiks, J.; Jatiningrum, R. S.; Christensen, B. A.

2017-12-01

Global climate was characterized by intriguing climate variability during the Late Pliocene (3.6 to 2.59 Ma): a brief (<100 kyr) but intense glaciation (MIS M2) interrupted the relatively warm climate state around 3.3 Ma. Until today, different hypotheses exist to explain why this glaciation event was so intense, and why the global climate system returned to warm Pliocene conditions relatively quickly. One of these proposed mechanisms is a reduced equator-to-pole heat transfer, in response to a tectonically reduced Indonesian Throughflow (ITF; De Schepper et al., 2014; Karas et al., 2011a, b). However, the scarcity of orbital-scale continuous climate archives in the outflow of the Indonesian Seaway hampers testing this hypothesis. To assess the supposed relationship between mid-Pliocene glaciations and latitudinal heat transport through the Indonesian Throughflow, we constructed a 3-kyr resolution planktonic δ18OG.sacculiferrecord for the 3.9 - 2.7 Ma interval from Site U1463 (18°59'S, 117°37'E; Northwestern Australian Shelf; IODP Expedition 356 "Indonesian Throughflow"). The U1463 oxygen isotope record concurs exceptionally well with the sea surface temperature (SST) record from Site 806 (0°19'N, 159°22'E) in the West Pacific Warm Pool (Wara et al., 2005), even during MIS M2. Hence, Site U1463 suggests an uninterrupted ITF signal during Pliocene glaciations. Surprisingly though, the U1463 δ18OG.sacculifer record exhibits a 0.5‰ offset with the nearby Site 763 record (20°35'S, 112°12'E) around MIS M2. This implies that Site 763, which lies a bit further offshore than U1463, fits better with Indian Ocean SST records (e.g. Site 214; Karas et al., 2009) across MIS M2. In conclusion, the U1463 data reveal that heat-transport through the Indonesian Throughflow did not shut down completely during MIS M2. However, its intensity decreased during MIS M2, causing Site 763 to temporarily reflect an Indian Ocean, rather than an ITF signal. References De Schepper, S

Stratigraphy, geochronology, and paleoenvironments of Miocene - Pliocene boundary of San Fernando, Belén (Catamarca, northwest of Argentina)

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Bonini, Ricardo A.; Georgieff, Sergio M.; Candela, Adriana M.

2017-11-01

The Santa María-Hualfín Basin was proposed as a regional synchronous lithostratigraphic depocenter in the geological province of Northwestern Pampean Ranges, Northwestern Argentina. However, new 40Ar-39Ar dating indicates that deposits toward the east, in Santa María Valley (Santa María Department), are younger than the western depocenter in San Fernando (Belén Department). Therefore, it would be more appropriate to study these valleys as separate basins, each one with its own tecto-sedimentary features. The east basin, named in this paper Villavil-Quillay, constitutes an elongated independent basin that developed along the front of the eastern Puna bordering with Papachacra and Durazno Ranges. This basin is composed of more than 3000 m of mudstone, sandstone, conglomerates, volcaniclastic and pyroclastic deposits. Villavil-Quillay basin develops onto a peneplain of Precambrian and lower Cambrian rocks, most of which are metamorphic and granites rocks. The sedimentary fill consists of Cretaceous? and Cenozoic continental deposits. The Cenozoic record is composed of a) the Santa María Group (Miocene-Pliocene), formed by Las Arcas, Chiquimil, Andalhuala and Corral Quemado Formations, and b) the Punaschotter unit (Puna's Gravels in German, Pleistocene). This study involves the Andalhuala, Corral Quemado and Punaschotter deposits cropping out in San Fernando area. The set of identified facies assemblage corresponding to the Andalhuala Formation shows a vertical variation of fluvial sub-environments, varying from permanent sandy braided rivers to gravel rivers and aeolian dunes culminating in an alluvial dry cycle. While facies assemblages of the Corral Quemado Formation allow inferring the development of ephemeral water bodies from secondary channels on the floodplain, the Punaschotter conglomerates indicate the development of gravel channels and bars. Three samples of tuffs interbedded in the sedimentary levels of Andalhuala Formation were dated indicating that

Alluvial systems as archives for environmental change at a Hominid site with Oldowan archaeological occurrences: the Homa Peninsula, southwestern Kenya

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Vincent, Thomas; Whitfield, Elizabeth; Kirby, Jason; Hunt, Christopher; Bishop, Laura; Plummer, Thomas; Ditchfield, Peter

2016-04-01

The Homa Peninsula, southwestern Kenya, preserves fossiliferous sedimentary sequences dating to the Plio-Pleistocene. Evidence of hominids inhabiting an open grassland setting and utilising Oldowan tools has been reported here, as well as some of the oldest known traces of hominin activity. Reconstructions of the palaeoenvironment have suggested that alluvial and lake marginal environments on a grassy plain, between wooded slopes and a permanent water body might be plausible. However, these interpretations are based only on field sedimentological analyses and stable isotope analysis at a single site on the peninsula (Kanjera South). It is the aim of this study to utilise a multiproxy approach to develop our understanding of the palaeoenvironmental characteristics here. Sediments will also be characterized at a new site (Nyayanga) through field analyses, as well as through analyses of particle size, siliceous microfossils (diatoms, phytoliths and sponge spicules), pollen and stable isotopes. By utilizing this approach, new insights into the palaeoecology, palaeohydromorphology and palaeoclimate of the locale may be revealed, expanding the limited data available to palaeoanthropological studies of Oldowan occurrences in east Africa. Efforts to refine palaeoenvironmental reconstructions of Kanjera South through particle size analysis have shown that sediments in the lower beds of the sequence are characterised by poor sorting, a bimodal distribution and sand/silty-sand grade material. This suggests rapid deposition and/or a variable hydrological regime and may represent the role of relatively unconfined ephemeral channels in the transportation and deposition of sediments. Fluvial reworking of aeolian sediments, most likely during unconfined flood events may also have occurred.

Sr isotope evidence for a lacustrine origin for the upper Miocene to Pliocene Bouse Formation, lower Colorado River trough, and implications for timing of Colorado Plateau uplift

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Spencer, J.E.; Patchett, P.J.

1997-01-01

The upper Miocene to Pliocene Bouse Formation in the lower Colorado River trough, which consists largely of siltstone with basal tufa and marl, has been interpreted as estuarine on the basis of paleontology. This interpretation requires abrupt marine inundation that has been linked to early rifting in the Gulf of California and Salton trough. New strontium isotope measurements reported here from carbonates and invertebrate shells in the Bouse Formation reveal no evidence of marine water, but are consistent with deposition in a lake or chain of lakes fed by the Colorado River. Furthermore, the absence of a southward decrease in 87Sr/86Sr within the Bouse Formation does not support the estuarine model in which low 87Sr/86Sr marine Sr would have dominated the mouth of the hypothetical Bouse estuary. Elevation of originally marine 87Sr/86Sr in the Bouse Formation to its present level, due to postdepositional interaction with ground water, is unlikely because Sr from secondary calcite above, below, and within the Bouse Formation is consistently less radiogenic, not more, than Bouse marl and shells. In contrast to Bouse Sr, strontium from mollusks in tidal-flat and delta-front paleoenvironments in the contemporaneous Imperial Formation in the Salton trough and from the subsurface south of Yuma was derived from sea water and confirms the dominance of marine strontium near or at the mouth of the late Miocene to early Pliocene Colorado River. Inferred post-early Pliocene uplift of the Bouse Formation from below sea level to modern elevations of up to 550 m has been used to support a late Cenozoic uplift age for the nearby Colorado Plateau. This constraint on uplift timing is eliminated if the Bouse Formation is lacustrine.

Influences of sediment redistribution on sea-level changes along the U.S. Atlantic margin since the mid-Pliocene

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Li, Q.; Ferrier, K.; Austermann, J.; Mitrovica, J. X.

2017-12-01

The Orangeburg Scarp is a paleo-shoreline formed along the southeastern U.S. Atlantic coast during the mid-Pliocene warm period (MPWP; 3.3 - 2.9 Ma). The MPWP is a time of interest because it is often cited as an analog for modern climate and thus an important target for understanding sea-level responses to climate change. The present Orangeburg Scarp exhibits 40-meter variations in elevation along its length, implying that it has been warped since its formation, which complicates efforts to infer global ice volume at the MPWP. Previous studies have shown that the effects of glacial isostatic adjustment (GIA) and dynamic topography (DT) on sea level can explain a significant fraction of the observed variability in elevation along the Orangeburg Scarp. Here we build on these studies by using a gravitationally self-consistent ice age sea-level model to compute the effects of sediment loading and unloading on paleo-shoreline elevation since the mid-Pliocene. To constrain the sediment loading history in this region, we present a new compilation of erosion and deposition rates along the U.S. Atlantic margin, from which we generate a range of sediment redistribution scenarios since the MPWP. We simultaneously drive the sea-level model with these sediment redistribution histories and existing ice and dynamic topography histories. Our results show that sediment loading and unloading is capable of warping the elevation of this paleo-shoreline by 20 meters since its formation, similar in magnitude to the contributions from GIA and DT over the same time period. These results demonstrate that sediment redistribution can induce significant perturbations in sea-level markers from the MPWP, and thus accounting for its influence will improve reconstructions of sea level and global ice volume during the MPWP and perhaps other periods of relative ice age warmth.

Simulated variations of eolian dust from inner Asian deserts at the mid-Pliocene, last glacial maximum, and present day: contributions from the regional tectonic uplift and global climate change

Energy Technology Data Exchange (ETDEWEB)

Shi, Zhengguo; Liu, Xiaodong; An, Zhisheng [Chinese Academy of Sciences, State Key Laboratory of Loess Quaternary Geology (SKLLQG), Institute of Earth Environment, Xi' an (China); Yi, Bingqi; Yang, Ping [Texas A and M University, College Station, TX (United States); Mahowald, Natalie [Cornell University, Ithaca, NY (United States)

2011-12-15

Northern Tibetan Plateau uplift and global climate change are regarded as two important factors responsible for a remarkable increase in dust concentration originating from inner Asian deserts during the Pliocene-Pleistocene period. Dust cycles during the mid-Pliocene, last glacial maximum (LGM), and present day are simulated with a global climate model, based on reconstructed dust source scenarios, to evaluate the relative contributions of the two factors to the increment of dust sedimentation fluxes. In the focused downwind regions of the Chinese Loess Plateau/North Pacific, the model generally produces a light eolian dust mass accumulation rate (MAR) of 7.1/0.28 g/cm{sup 2}/kyr during the mid-Pliocene, a heavier MAR of 11.6/0.87 g/cm{sup 2}/kyr at present, and the heaviest MAR of 24.5/1.15 g/cm{sup 2}/kyr during the LGM. Our results are in good agreement with marine and terrestrial observations. These MAR increases can be attributed to both regional tectonic uplift and global climate change. Comparatively, the climatic factors, including the ice sheet and sea surface temperature changes, have modulated the regional surface wind field and controlled the intensity of sedimentation flux over the Loess Plateau. The impact of the Tibetan Plateau uplift, which increased the areas of inland deserts, is more important over the North Pacific. The dust MAR has been widely used in previous studies as an indicator of inland Asian aridity; however, based on the present results, the interpretation needs to be considered with greater caution that the MAR is actually not only controlled by the source areas but the surface wind velocity. (orig.)

Evaluation of the corrosion resistance of an epoxy-polyamide coating containing different ratios of micaceous iron oxide/Al pigments

International Nuclear Information System (INIS)

Nikravesh, B.; Ramezanzadeh, B.; Sarabi, A.A.; Kasiriha, S.M.

2011-01-01

Research highlights: → The corrosion resistance of the coating was improved using MIO and Al pigments. → The greatest coating corrosion resistance was observed at MIO/Al ratio of 10/90. → The cathodic disbonded area of the coating was decreased using MIO and Al particles. → The lowest disbonded area was observed at MIO/Al ratio of 10/90. → Al particles had high capability of reacting with the OH - ions. - Abstract: The corrosion resistance of an epoxy coating reinforced with different ratios of MIO/Al pigments was studied. The coatings properties were investigated by an electrochemical impedance spectroscopy (EIS), salt spray test, cathodic disbonding and a scanning electron microscope (SEM). The corrosion resistance of the epoxy coating was improved using MIO (micaceous iron oxide) and Al pigments. The corrosion resistance of the purely Al pigmented coating was considerably greater than the purely MIO pigmented coating. The cathodic disbonded area of coating was decreased using MIO and Al pigments. The decrease in disbonded area was more pronounced in the presence of Al particles.

Paleoenvironmental implications from biomarker and stable isotope investigations on the Pliocene Velenje lignite seam (Slovenia)

Energy Technology Data Exchange (ETDEWEB)

Bechtel, A.; Sachsenhofer, R.F.; Markic, M.; Gratzer, R.; Lucke, A.; Puttmann, W. [Montan University of Leoben, Leoben (Austria)

2003-07-01

A Pliocene lignite seam up to 160 m thick occurs in the Velenje basin (Slovenia). The seam originated in a topogenous mire and evolved within a non-marine, transgressive setting. Differences in soluble organic matter yield and hydrocarbon content of borehole samples from the lignite are related to differences in the composition of free lipids of microbial origin and/or hydrocarbons derived from the biogeochemical degradation of plant tissue. Variations of the redox conditions within the mire are reflected by pristane/phytane ratios. The abundance of terpenoid biomarkers indicates the predominance of gymnosperms over angiosperms, which is consistent with palynomorphic spectra dominated by pollen of the Sequoia-Taxodium-Metasequoia plant community rather than by angiosperms. Evidence is also provided that the content of land plant derived biomarkers and the preservation of plant tissue is controlled by the input of resin-rich, decay-resistant conifers.

Fossil bird eggs from the Pliocene of Laetoli, Tanzania: Their taxonomic and paleoecological relationships

Science.gov (United States)

Harrison, Terry

2005-04-01

Recent paleontological investigations at the Pliocene site of Laetoli and at neighboring localities on the Eyasi Plateau of northern Tanzania have led to the recovery of a sizable collection of fossil bird eggs. The material comes from the Upper Laetolil Beds, dated at ˜3.6-3.8 Ma, and the Lower Laetolil Beds, dated at 3.8 Ma to older than 4.3 Ma. The preservation of relatively complete eggs (other than those of ratites) is an extremely rare occurrence in the fossil record, and Laetoli is the only locality in Africa that has produced such well-preserved eggs. Deposition of carbonatite air-fall tuffs led to the rapid burial of the eggs sub-aerially, and they were then preserved in paleosols that were geochemically conducive to their preservation. The collection of fossil eggs from Laetoli can be assigned to at least five different species of ground-nesting birds, including two or three species of francolins, a species of guineafowl, and a larger bird of uncertain taxonomic status about the size of a bustard. Most of the eggs can be assigned to a large species of Francolinus, similar in size to the extant F. afer and F. leucoscepus. A smaller species of francolin, about the size of Francolinus coqui or F. sephaena, is also represented, but is less common. A single egg may represent an even smaller species of francolin, about the size of Francolinus lathami or F. nahani, but its attribution to Francolinus is less certain. The evidence of at least two species of Francolinus at Laetoli indicates that francolins were already taxonomically diverse in East Africa by the mid-Pliocene. Three eggs are similar in their overall dimensions and morphology to the living Numida meleagris, the helmeted guineafowl. An avian community including at least one small species of francolin, a larger francolin, and a guineafowl (as well as ostriches and a vulture) implies that the paleoecology at Laetoli was likely to have been open woodland, bushland, savanna or grassland. However

Shape analysis of spatial relationships between orbito-ocular and endocranial structures in modern humans and fossil hominids.

Science.gov (United States)

Pereira-Pedro, Ana Sofia; Masters, Michael; Bruner, Emiliano

2017-12-01

The orbits and eyes of modern humans are situated directly below the frontal lobes and anterior to the temporal lobes. Contiguity between these orbital and cerebral elements could generate spatial constraints, and potentially lead to deformation of the eye and reduced visual acuity during development. In this shape analysis we evaluate whether and to what extent covariation exists between ocular morphology and the size and spatial position of the frontal and temporal areas in adult modern humans. Magnetic resonance imaging (MRI) was used to investigate patterns of variation among the brain and eyes, while computed tomography (CT) was used to compare cranial morphology in this anatomical region among modern humans, extinct hominids and chimpanzees. Seventeen landmarks and semi-landmarks that capture the outline of the eye, frontal lobe, anterior fossa/orbital roof and the position of the temporal tips were sampled using lateral scout views in two dimensions, after projection of the average grayscale values of each hemisphere, with midsagittal and parasagittal elements overlapped onto the same plane. MRI results demonstrated that eye position in adult humans varies most with regard to its horizontal distance from the temporal lobes and, secondly, in its vertical distance from the frontal lobes. Size was mainly found to covary with the distance between the eye and temporal lobes. Proximity to these cerebral lobes may generate spatial constraints, as some ocular deformation was observed. Considering the CT analysis, modern humans vary most with regard to the orientation of the orbits, while interspecific variation is mainly associated with separation between the orbits and endocranial elements. These findings suggest that size and position of the frontal and temporal lobes can affect eye and orbit morphology, though potential effects on eye shape require further study. In particular, possible effects of these spatial and allometric relationships on the eye and vision

Vicariance and Its Impact on the Molecular Ecology of a Chinese Ranid Frog Species-Complex (Odorrana schmackeri, Ranidae.

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Yongmin Li

Full Text Available Paleogeological events and Pleistocene climatic fluctuations have had profound influences on the genetic patterns and phylogeographic structure of species in southern China. In this study, we investigated the population genetic structure and Phylogeography of the Odorrana schmackeri species complex, mountain stream-dwelling odorous frogs, endemic to southern China. We obtained mitochondrial sequences (1,151bp of the complete ND2 gene and two flanking tRNAs of 511 individuals from 25 sites for phylogeographic analyses. Phylogenetic reconstruction revealed seven divergent evolutionary lineages, with mean pairwise (K2P sequence distances from 7.8% to 21.1%, except for a closer ND2 distance (3.4%. The complex geological history of southern China drove matrilineal divergence in the O. schmackeri species complex into highly structured geographical units. The first divergence between lineage A+B and other lineages (C-G had likely been influenced by the uplift of coastal mountains of Southeast China during the Mio-Pliocene period. The subsequent divergences between the lineages C-G may have followed the formation of the Three Gorges and the intensification of the East Asian summer monsoon during the late Pliocene and early Pleistocene. Demographic analyses indicated that major lineages A and C have been experienced recent population expansion (c. 0.045-0.245 Ma from multiple refugia prior to the Last Glacial Maximum (LGM. Molecular analysis suggest that these seven lineages may represent seven different species, three described species and four cryptic species and should at least be separated into seven management units corresponding to these seven geographic lineages for conservation.

Petrologic evolution of Miocene-Pliocene mafic volcanism in the Kangal and Gürün basins (Sivas-Malatya), central east Anatolia: Evidence for Miocene anorogenic magmas contaminated by continental crust

Science.gov (United States)

Kocaarslan, Ayça; Ersoy, E. Yalçın

2018-06-01

This study discusses the geochemical features of the Early-Middle Miocene and Pliocene basaltic (SiO2 = 46-52; MgO = 6-10 wt%) to andesitic (SiO2 = 59; MgO = 4 wt%) rocks exposed in the Gürün and Kangal basins (Sivas, eastern part of central Anatolia), respectively. The basaltic rocks are characterized by alkaline to tholeiitic affinities, while the more evolved andesitic samples show calc-alkaline affinity. Trace element variations reveal that they can be evaluated in three sub-groups, each represented by different contents of trace elements for given Nb contents. Primary magmas of each groups were likely produced by different degrees of partial melting ( 1-2, 2-3, 7-10% respectively) from a common mantle source, subsequently underwent different degrees of fractionation and crustal contamination. Derivation from a common mantle source of the primitive magmas of each group is supported by similar Sr, Nd and Pb isotopic ratios. Increasing degrees of partial melting seem to be responsible for the alkaline to tholeiitic variation among the basaltic samples, while higher degrees of crustal contamination (AFC) resulted in calc-alkaline affinity of the more evolved samples. Most primitive Pliocene samples show intra-plate (anorogenic) geochemical features, while the more evolved Miocene calc-alkaline samples resemble geochemically subduction-related (orogenic) magmatic rocks. However, on the basis of detailed geochemical models, we propose that the calc-alkaline affinity among the Miocene samples can also be gained by crustal contamination of their primary magmas which were also anorogenic in character. If this is true, overall, the Miocene and Pliocene basaltic to andesitic rocks in the Gürün and Kangal basins appear to may have formed by variable degrees of partial melting of a common anorogenic mantle that had not been subject to subduction-related metasomatism. This is an alternative approach to the general view assuming the Early-Middle Miocene magmatic activity

A primitive Late Pliocene cheetah, and evolution of the cheetah lineage

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Christiansen, Per; Mazák, Ji H.

2009-01-01

The cheetah lineage is a group of large, slender, and long-limbed cats with a distinctive skull and dental morphology, of which only the extant cheetah (Acinonyx jubatus) is present today. The lineage is characterized by having abbreviated, tall, and domed crania, and a trenchant dentition with a much reduced, posteriorly placed protocone on the upper carnassial. In this article, we report on a new discovery of a Late Pliocene specimen from China with an estimated age of ≈2.2–2.5 million years, making it one of the oldest specimens known to date. A cladistic analysis confirmed that it is the most primitive cheetah known, and it shares a number of unambiguous derived cranial traits with the Acinonyx lineage, but has more primitive dentition than previously known cheetahs, demonstrating that the many unusual skull and dental characters hitherto considered characteristic of cheetahs evolved in a gradual fashion. Isolated teeth of primitive cheetahs may not be recognizable as such, but can be confused with, for instance, those of leopards or other similar-sized pantherine cats or pumas. The age and morphology of the new specimen supports an Old World origin of the cheetah lineage, not a New World one, as has been suggested. We name the new species Acinonyx kurteni in honor of the late Björn Kurtén. PMID:19114651

Evidence for late Pliocene deglacial megafloods in the Gulf of Mexico

Science.gov (United States)

Wang, Z.; Gani, M. R.

2017-12-01

The paleoclimatic significance of giant sedimentary structures developed under unconfined Froude-supercritical sediment gravity flows in subaqueous settings is considerably under-examined. This research, for the first time, extensively documents >20-km-wide and 200-m-thick Plio-Pleistocene giant sediment waves in the northern Gulf of Mexico continental slope using 3D seismic data, showing waveform morphology in unprecedented detail. Published biostratigraphic data help constraining the geologic age of these deposits. The results of numerical and morphological analyses suggest that such large-scale bedforms were formed under sheet-like unconfined Froude-supercritical turbidity currents as cyclic steps. Paleohydraulic reconstruction (e.g., flow velocity, discharge, and unit flux), in association with other evidence like geologic age, published stable isotope records, and temporal rarity, points out that the responsible Froude-supercritical turbidity currents were most likely triggered by deglacial catastrophic outburst floods during the late Pliocene to early Pleistocene. Laurentide Ice Sheet outburst floods to the Gulf of Mexico have previously been documented based mainly on deep-sea cores during the last several interglacial episodes in the late Pleistocene. Our megaflood events constitute, by far, the oldest record of the glacial outburst floods during the Quaternary Ice Age anywhere in the world. This study suggests that such pervasive occurrence of large-scale sediment waves likely serve as a proxy for extreme events like catastrophic megafloods.

A primitive Late Pliocene cheetah, and evolution of the cheetah lineage.

Science.gov (United States)

Christiansen, Per; Mazák, Ji H

2009-01-13

The cheetah lineage is a group of large, slender, and long-limbed cats with a distinctive skull and dental morphology, of which only the extant cheetah (Acinonyx jubatus) is present today. The lineage is characterized by having abbreviated, tall, and domed crania, and a trenchant dentition with a much reduced, posteriorly placed protocone on the upper carnassial. In this article, we report on a new discovery of a Late Pliocene specimen from China with an estimated age of approximately 2.2-2.5 million years, making it one of the oldest specimens known to date. A cladistic analysis confirmed that it is the most primitive cheetah known, and it shares a number of unambiguous derived cranial traits with the Acinonyx lineage, but has more primitive dentition than previously known cheetahs, demonstrating that the many unusual skull and dental characters hitherto considered characteristic of cheetahs evolved in a gradual fashion. Isolated teeth of primitive cheetahs may not be recognizable as such, but can be confused with, for instance, those of leopards or other similar-sized pantherine cats or pumas. The age and morphology of the new specimen supports an Old World origin of the cheetah lineage, not a New World one, as has been suggested. We name the new species Acinonyx kurteni in honor of the late Björn Kurtén.

Antilopinae (Bovidae, Mammalia from the Lower Pliocene of Teruel Basin (Spain

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Morales, J.

2006-12-01

Full Text Available Two genera of Antilopinae are identified in the Lower Pliocene localities of the Teruel Basin: Hispanodorcas and Gazella. Hispanodorcas is represented at La Calera by a new species, Hispanodorcas heintzi nov. sp., which is characterised by the development of a strong anterior keel in the horn cores. Gazella is represented in La Calera and Villalba Alta localities by a new species, Gazella soriae nov. sp., which is defined by its small size and weak transversal compression of the horn cores. A species smaller than Gazella soriae, Gazella baturra nov. sp. is identified at La Gloria 4.En los yacimientos del Plioceno inferior de la Fosa de Teruel se han identificado dos géneros de Antilopinae: Hispanodorcas y Gazella. Hispanodorcas está representado en La Calera por una nueva especie: Hispanodorcas heintzi nov. sp., que está caracterizada por el desarrollo de una fuerte quilla anterior en sus núcleos óseos de cuerno. Gazella está representada en La Calera y Villalba Alta por una nueva especie, Gazella soriae nov. sp., que está definida por su pequeña talla y escasa compresión transversal de los núcleos óseos de cuerno. Una especie de menor talla todavía que Gazella soriae se clasifica como Gazella baturra nov. sp. en La Gloria 4.

A REVISION OF THE PLIOCENE NATICIDS OF NORTHERN AND CENTRAL ITALY. II. THE SUBFAMILY NATICINAE: ADDITIONS TO COCHLIS, TANEA AND TECTONATICA

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LUCA PEDRIALI

2008-03-01

Full Text Available The present paper is the second in a series devoted to the revision of the Pliocene naticids of Northern and Central Italy. It concludes the section covering the calcareous operculum-bearing Naticinae and expands to 18 the total number of species and subspecies of this subfamily recovered so far from the Pliocene deposits of Italy. Of the six taxa considered in this study, two (epigloafuniculata and fredianii fully match the characters of the genus Cochlis Röding, 1798, one (koeneni is assigned to the genus Tanea Marwick, 1931, the rest (astensis, prietoi and tectula belong to the genus Tectonatica Sacco, 1890. All the six taxa considered in this paper are described and commented in the systematic account. One, Cochlis fredianii, is proposed as new. In the chapter treating the generic assignment of the studied taxa, the range of Tanea, hitherto used to allocate several Indo-Pacific species, is extended to the Mediterranean Basin as well, and the relations between Tectonatica and Cryptonatica Dall, 1892 are discussed. This study further demonstrates that the morphological characters of the teleoconch are of low significance in species recognition. In fact, should the characters be ranked, the operculum comes first and is the primary element, sufficient to distinguish each species. The protoconch and the color pattern are the second and third relevant attributes that can be used diagnostically for several taxa, but not always. The other shell features appear to be useful tools in separating species only occasionally. Some species lack distinctive shell characters and do require operculate specimens in order to be confidently 

Characterization of Pliocene and Miocene Formations in the Wilmington Graben, Offshore Los Angeles, for Large-Scale Geologic Storage of CO₂

Energy Technology Data Exchange (ETDEWEB)

Bruno, Michael [Geomechanics Technologies, Incorporated, Monrovia, CA (United States)

2014-12-08

Geomechanics Technologies has completed a detailed characterization study of the Wilmington Graben offshore Southern California area for large-scale CO₂ storage. This effort has included: an evaluation of existing wells in both State and Federal waters, field acquisition of about 175 km (109 mi) of new seismic data, new well drilling, development of integrated 3D geologic, geomechanics, and fluid flow models for the area. The geologic analysis indicates that more than 796 MMt of storage capacity is available within the Pliocene and Miocene formations in the Graben for midrange geologic estimates (P50). Geomechanical analyses indicate that injection can be conducted without significant risk for surface deformation, induced stresses or fault activation. Numerical analysis of fluid migration indicates that injection into the Pliocene Formation at depths of 1525 m (5000 ft) would lead to undesirable vertical migration of the CO₂ plume. Recent well drilling however, indicates that deeper sand is present at depths exceeding 2135 m (7000 ft), which could be viable for large volume storage. For vertical containment, injection would need to be limited to about 250,000 metric tons per year per well, would need to be placed at depths greater than 7000ft, and would need to be placed in new wells located at least 1 mile from any existing offset wells. As a practical matter, this would likely limit storage operations in the Wilmington Graben to about 1 million tons per year or less. A quantitative risk analysis for the Wilmington Graben indicate that such large scale CO₂ storage in the area would represent higher risk than other similar size projects in the US and overseas.

Avaliação das condições de envelhecimento do sistema catalítico versatato de neodímio/hidreto de di-isobutilalumínio/cloreto de t-butila na polimerização de 1,3-butadieno

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Neusa Maria Tocchetto Pires

2014-01-01

Full Text Available O objetivo deste trabalho foi estudar sistemas catalíticos ternários constituídos por versatato de neodímio, cloreto de t-butila e hidreto de di-isobutil-alumínio para a polimerização de 1,4-cis de butadieno em hexano. Foi investigado o efeito do envelhecimento natural do catalisador (1 a 60 dias a 8,5°C sobre a conversão, a atividade catalítica e a micro- e macroestrutura do polibutadieno. Foi estudado também o efeito do envelhecimento forçado (40°C, das diferentes fases do preparo do catalisador sobre as características da polimerização e do polímero sintetizado. Os polímeros foram caracterizados por cromatografia de exclusão por tamanho (SEC, espectroscopia na região do infravermelho (FT-IR, viscosimetria em solução e no estado fundido. O envelhecimento forçado das diferentes fases do catalisador (F1, F2, F3 e F4 afetou a conversão e a atividade catalítica de maneiras distintas. Os resultados de conversão e atividade catalítica mostraram que a fase mais afetada pelo envelhecimento forçado a 40°C foi a F1, etapa em que o versatato de neodímio é adicionado à solução de hidreto de di-isobutil-alumínio (Catalisador 447. A microestrutura não se alterou com o envelhecimento natural do catalisador enquanto que a macroestrutura mostrou dependência desta variável. Foi observado um ligeiro aumento na conversão e na atividade catalítica à medida que o tempo de envelhecimento do catalisador aumentou de 1 para 10 dias.

Clavicles, scapulae and humeri from the Sima de los Huesos site (Sierra de Atapuerca, Spain).

Science.gov (United States)

Carretero, J M; Arsuaga, J L; Lorenzo, C

1997-01-01

The scapulae, clavicles and humeri recovered from the Sima de los Huesos (SH) site between 1976 and 1994 are studied. All elements are briefly described anatomically with metrics and compared with other fossil hominids in order to establish the morphological pattern of the SH hominids. A minimum of 13 individuals are represented by the humeri in the SH sample. Almost all of them can be classified as adolescents and young adults. The morphology of the SH hominid shoulder girdle and humeri indicates that much of the shoulder morphology recognized in the later true Neandertal was present in Europe long before they appeared. Thus, this morphological pattern is not exclusive to Neandertals alone. The SH clavicles, scapulae and humeri share with the Neandertals many traits usually considered to be Neandertal specializations. The comparative analysis of the SH evidence suggests that most of the SH and Neandertal shared traits are either primitive features within the genus Homo or even for all hominids, or display high variability within different hominid samples. These traits must be used with caution, or not used at all, in phylogenetic analysis. There are, however, traits that to date have only been detected in the SH hominids and the Neanderials, which could be exclusive to the European phyletic lineage (clade) of Homo.

Site characterization and site response in Port-au-Prince, Haiti

Science.gov (United States)

Hough, Susan E.; Yong, Alan K.; Altidor, Jean Robert; Anglade, Dieuseul; Given, Douglas D.; Mildor, Saint-Louis

2011-01-01

Waveform analysis of aftershocks of the Mw7.0 Haiti earthquake of 12 January 2010 reveals amplification of ground motions at sites within the Cul de Sac valley in which Port-au-Prince is situated. Relative to ground motions recorded at a hard-rock reference site, peak acceleration values are amplified by a factor of approximately 1.8 at sites on low-lying Mio-Pliocene deposits in central Port-au-Prince and by a factor of approximately 2.5–3 on a steep foothill ridge in the southern Port-au-Prince metropolitan region. The observed amplitude, predominant periods, variability, and polarization of amplification are consistent with predicted topographic amplification by a steep, narrow ridge. A swath of unusually high damage in this region corresponds with the extent of the ridge where high weak-motion amplifications are observed. We use ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery to map local geomorphology, including characterization of both near-surface and of small-scale topographic structures that correspond to zones of inferred amplification.

Thallium in mineral resources extracted in Poland

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Bojakowska I.

2013-04-01

Full Text Available Thallium concentrations in primary mineral commodities extracted in Poland and processed in high temperatures were determined by ICP-MS method. Samples of hard and brown coal, copper-silver and zinclead ores, argillaceous and calcareous rocks of different genesis and age were analyzed. The highest thallium concentrations occur in the zinc-lead ores, the average content being of 52.1 mg/kg. The copper ores contain in average 1.4 mg/kg of thallium. Hard coals from the Upper Silesian Coal Basin display higher thallium content than those exploited in the Lublin Coal Basin. Brown coals from Turow deposit distinguish by much higher values, 0.7 mg/kg Tl, than those from huge Bełchatów and smaller Konin-Turek region deposits. Average thallium concentrations in clays used for ceramic materials are lower than 1 mg/kg, except of Mio-Pliocene Slowiany deposit. The average content of thallium in the studied limestone and dolomite raw materials for cement, lime, and metallurgical flux, and refractories is very low in comparison to the average amounts in the world carbonate rocks.

Combined ESR/U-series chronology of Acheulian hominid-bearing layers at Trinchera Galería site, Atapuerca, Spain.

Science.gov (United States)

Falguères, Christophe; Bahain, Jean-Jacques; Bischoff, James L; Pérez-González, Alfredo; Ortega, Ana Isabel; Ollé, Andreu; Quiles, Anita; Ghaleb, Bassam; Moreno, Davinia; Dolo, Jean-Michel; Shao, Qingfeng; Vallverdú, Josep; Carbonell, Eudald; Bermúdez de Castro, Jose María; Arsuaga, Juan Luis

2013-08-01

The Sierra de Atapuerca, northern Spain, is known from many prehistoric and palaeontological sites documenting human prehistory in Europe. Three major sites, Gran Dolina, Galería and Sima del Elefante, range in age from the oldest hominin of Western Europe dated to 1.1 to 1.3 Ma (millions of years ago) at Sima del Elefante to c.a. 0.2 Ma on the top of the Galería archaeological sequence. Recently, a chronology based on luminescence methods (Thermoluminescence [TL] and Infrared Stimulated Luminescence [IRSL]) applied to cave sediments was published for the Gran Dolina and Galería sites. The authors proposed for Galería an age of 450 ka (thousands of years ago) for the units lower GIII and GII, suggesting that the human occupation there is younger than the hominid remains of Sima de los Huesos (>530 ka) around 1 km away. In this paper, we present new results obtained by combined Electron Spin Resonance/Uranium-series (ESR/U-series) dating on 20 herbivorous teeth from different levels at the Galería site. They are in agreement with the TL results for the upper part of the stratigraphic sequence (GIV and GIIIb), in the range of between 200 and 250 ka. But for the GIIIa to GIIb levels, the TL ages become abruptly older by 200 ka while ESR ages remain relatively constant. Finally, the TL and ESR data agree in the lowest part of the section (GIIa); both fall in the range of around 350-450 ka. Our results suggest a different interpretation for the GII, GIII and GIV units of Galería and the upper part of Gran Dolina (TD10 and TD11) than obtained by TL. The ESR/U-series results are supported by a Bayesian analysis, which allows a better integration between stratigraphic information and radiometric data. Copyright © 2013 Elsevier Ltd. All rights reserved.

The oldest record of Alligator sinensis from the Late Pliocene of Western Japan, and its biogeographic implication

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Iijima, Masaya; Takahashi, Keiichi; Kobayashi, Yoshitsugu

2016-07-01

The late Cenozoic fossil record of alligators in East Asia is crucial in understanding the origin and past distribution of Asian alligators that are now represented by a single species, Alligator sinensis. This study reports a partial skeleton of A. sinensis from the Late Pliocene (approximately 3.0 Ma) of western Japan. This Japanese A. sinensis is large in size (>200 cm total length), comparable to the maximum size of extant individuals. It demonstrates the oldest record of A. sinensis and wider distribution of this species in the past. Tectonic and geographic history of East Asia suggests that alligators presumably dispersed into Japan before 25 Ma or after 10 Ma, yet finally were wiped out from Japan due to the semi-isolated condition of the Japanese island arc and the deteriorated climate during the Plio-Pleistocene.

Scaldiporia vandokkumi, a new pontoporiid (Mammalia, Cetacea, Odontoceti from the Late Miocene to earliest Pliocene of the Westerschelde estuary (The Netherlands

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Klaas Post

2017-11-01

Full Text Available Background The family Pontoporiidae (Cetacea, Odontoceti, Inioidea is currently represented in our oceans by just one species of diminutive dolphin (Pontoporia blainvillei, franciscana. Although P. blainvillei is limited to coastal waters of the South Atlantic along Brazil, Uruguay and Argentina, multiple Miocene and Pliocene fossils indicate the past presence of members of the family in the South Atlantic, South Paciifc and North Atlantic oceans. Our comprehension of the origin and diversity of this clade and of the relationships of its members with other inioids is hampered by the fact that part of the described fossil specimens, especially from the North Atlantic realm, are cranial fragments often associated to limited stratigraphic information. Methods Based on an almost complete fossil cranium of pontoporiid from the Westerschelde estuary, The Netherlands, whose preservation allows for detailed morphological observations, we describe a new genus and species. The latter is compared to other pontoporiids, as well as a few non-pontoporiid inioids. A phylogenetic analysis is performed to investigate the relationship of S. vandokkumi with the best-known extinct and extant inioids. Palynological analysis of the sediment associated to the holotype is used to assess its geological age. Results and discussion The new genus and species Scaldiporia vandokkumi is characterized among others by greatly thickened premaxillary eminences reaching the level of the antorbital notch. Palynologically dated from the late Tortonian—earliest Zanclean (7.6–5 Ma, Late Miocene—earliest Pliocene, this new pontoporiid confirms the surprising past diversity of marine inioids in the North Atlantic area. Finally the content of the pontoporiid subfamily Brachydelphininae is briefly discussed.

Geological events and Pliocene climate fluctuations explain the phylogeographical pattern of the cold water fish Rhynchocypris oxycephalus (Cypriniformes: Cyprinidae) in China.

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Yu, Dan; Chen, Ming; Tang, Qiongying; Li, Xiaojuan; Liu, Huanzhang

2014-10-25

Rhynchocypris oxycephalus is a cold water fish with a wide geographic distribution including the relatively warm temperate regions of southern China. It also occurs in second- and third-step geomorphic areas in China. Previous studies have postulated that high-altitude populations of R. oxycephalus in southern China are Quaternary glacial relics. In this study, we used the mitochondrial gene Cytb and the nuclear gene RAG2 to investigate the species phylogeographical patterns and to test two biogeographic hypotheses: (1) that divergence between lineages supports the three-step model and (2) climatic fluctuations during the Quaternary resulted in the present distribution in southern China. Phylogenetic analysis detected three major matrilines (A, B, and C); with matrilines B and C being further subdivided into two submatrilines. Based on genetic distances and morphological differences, matriline A potentially represents a cryptic subspecies. The geographic division between matrilines B and C coincided with the division of the second and third geomorphic steps in China, suggesting a historical vicariance event. Pliocene climatic fluctuations might have facilitated the southwards dispersal of R. oxycephalus in matriline C, with the subsequent warming resulting in its split into submatrilines C1 and C2, leaving submatriline C2 as a relic in southern China. Our study demonstrates that geological events (three steps orogenesis) and climate fluctuations during the Pliocene were important factors in shaping phylogeographical patterns in R. oxycephalus. Notably, no genetic diversity was detected in several populations, all of which possessed unique genotypes. This indicates the uniqueness of local populations and calls for a special conservation plan for the whole species at the population level.

Sweet vernal grasses (Anthoxanthum) colonized African mountains along two fronts in the Late Pliocene, followed by secondary contact, polyploidization and local extinction in the Pleistocene.

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Tusiime, Felly Mugizi; Gizaw, Abel; Wondimu, Tigist; Masao, Catherine Aloyce; Abdi, Ahmed Abdikadir; Muwanika, Vincent; Trávníček, Pavel; Nemomissa, Sileshi; Popp, Magnus; Eilu, Gerald; Brochmann, Christian; Pimentel, Manuel

2017-07-01

High tropical mountains harbour remarkable and fragmented biodiversity thought to a large degree to have been shaped by multiple dispersals of cold-adapted lineages from remote areas. Few dated phylogenetic/phylogeographic analyses are however available. Here, we address the hypotheses that the sub-Saharan African sweet vernal grasses have a dual colonization history and that lineages of independent origins have established secondary contact. We carried out rangewide sampling across the eastern African high mountains, inferred dated phylogenies from nuclear ribosomal and plastid DNA using Bayesian methods, and performed flow cytometry and AFLP (amplified fragment length polymorphism) analyses. We inferred a single Late Pliocene western Eurasian origin of the eastern African taxa, whose high-ploid populations in one mountain group formed a distinct phylogeographic group and carried plastids that diverged from those of the currently allopatric southern African lineage in the Mid- to Late Pleistocene. We show that Anthoxanthum has an intriguing history in sub-Saharan Africa, including Late Pliocene colonization from southeast and north, followed by secondary contact, hybridization, allopolyploidization and local extinction during one of the last glacial cycles. Our results add to a growing body of evidence showing that isolated tropical high mountain habitats have a dynamic recent history involving niche conservatism and recruitment from remote sources, repeated dispersals, diversification, hybridization and local extinction. © 2017 John Wiley & Sons Ltd.

Development of Miocene-Pliocene reef trend, St. Croix, U. S. Virgin Islands

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Gill, I.; Eby, D.E.; Hubbard, D.K.; Frost, S.H.

1988-01-01

The Miocene-Pliocene reef trend on St. Croix, U.S. Virgin Islands, rims the present southern western coasts of the island and includes accompanying lagoonal and forereef facies. The reef trend was established on a foram-algal bank facies that represents basinal shallowing from the deep-water pelagic and hemipelagic facies of the Miocene Kingshill Limestone. Information on facies distribution and thickness is derived from rock exposures and 22 test wells drilled to a maximum depth of 91 m. The greatest thickness of the reef facies exists in a subsidiary graben on the south coast of St. Croix. The thickness of the reef section in this locality is due to preservation of the section in a downdropped block. Reef faunas include extant corals, as well as several extinct genera. Extant corals (e.g. Montastrea annularis, Diploria sp., and Porites porites) and extinct corals (e.g., Stylophora affinis, Antillea bilobata, and Thysanus sp.) are the main reef frame-builders. Coralline algea and large benthic foraminifera are significant contributors to the sediments both prior to and during scleractinian reef growth. Dolomitization and calcite cementation occur prominantly in an area corresponding to a Holocene lagoon. The spatial distribution of the dolomite suggests that the lagoon is a Tertiary feature directly related to the dolomitization process. Stable isotopic values suggest dolomitization of fluids of elevated salinity.

Possible brucellosis in an early hominin skeleton from sterkfontein, South Africa.

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Ruggero D'Anastasio

Full Text Available We report on the paleopathological analysis of the partial skeleton of the late Pliocene hominin species Australopithecus africanus Stw 431 from Sterkfontein, South Africa. A previous study noted the presence of lesions on vertebral bodies diagnosed as spondylosis deformans due to trauma. Instead, we suggest that these lesions are pathological changes due to the initial phases of an infectious disease, brucellosis. The macroscopic, microscopic and radiological appearance of the lytic lesions of the lumbar vertebrae is consistent with brucellosis. The hypothesis of brucellosis (most often associated with the consumption of animal proteins in a 2.4 to 2.8 million year old hominid has a host of important implications for human evolution. The consumption of meat has been regarded an important factor in supporting, directing or altering human evolution. Perhaps the earliest (up to 2.5 million years ago paleontological evidence for meat eating consists of cut marks on animal remains and stone tools that could have made these marks. Now with the hypothesis of brucellosis in A. africanus, we may have evidence of occasional meat eating directly linked to a fossil hominin.

Manganês, zinco, cádmio, chumbo, mercúrio e crômio no chorume de aterro sanitário em Dourados, MS, Brasil

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Priscilla Fracalossi Riguetti

2015-01-01

Full Text Available Neste estudo analisaram-se as concentrações de manganês, zinco, cádmio, chumbo, mercúrio e crômio, em amostras de chorume coletado no aterro sanitário de Dourados/MS. Foram retiradas amostras de dois reservatórios, um com tratamento aeróbio e outro com tratamento anaeróbio. Foram realizadas quatro coletas de 2012 a 2013, compreendendo períodos de seca e de chuvas. As concentrações dos metais foram determinadas por espectrometria de absorção atômica, modalidade chama. A comparação de resultados entre os dois reservatórios e entre as coletas foi realizada empregando-se análise de variância com nível de confiança de 95%. A análise dos resultados mostrou diferenças, quanto à concentração dos metais, somente entre as coletas. Os elementos manganês, zinco e chumbo apresentaram maiores concentrações nos períodos chuvosos e os demais elementos nos períodos de seca. De forma geral, apenas o índice pluviométrico interferiu nas concentrações dos metais estudados, também não se observaram variações de pH e condutividade elétrica ao longo do experimento.

The stratigraphic distribution of large marine vertebrates and shell beds in the Pliocene of Tuscany

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Dominici, Stefano; Benvenuti, Marco; Danise, Silvia

2015-04-01

The record of 337 shark fossils, 142 cetaceans and 10 sea cows from the Pliocene of Tuscany, mostly from historical museum collections, is revised. The majority of these fossils are concentrated at a few geographic sites from separated hinterland basins, on the South-Western side of the Northern Apennines. To better understand the meaning of these concentrations, the sequence stratigraphic distribution of more recent findings of large marine vertebrates is reconstructed against a high-resolution framework based on sedimentary facies analysis. These remains are usually covered by, or included in mudstones deposited far from the coast (N=12), skeletons being usually articulated, slightly displaced, and often bioeroded. A minor part of better preserved articulated skeletons is associated with sandstones from deltaic paleonenvironments (N=2). Marine mammal and shark remains may be associated with laterally-continuous shell accumulations, a type of concentration occurring at maximum flooding surfaces, separating relatively coarse-grained facies from open marine mudstones. Shell beds were bulk-sampled at 66 locations from six basins, covering a wide range of sedimentary facies, and spanning a chronologic interval of about 2.5 million years. A dataset of 62,655 mollusc specimens belonging to 496 species formed the basis of a statistical study to reconstruct the structure of the benthic communities, and to estimate paleodepths from intertidal to upper bathyal settings. Mollusc associations closely mirror the distribution of sedimentary facies, allowing for a fine tuning of the sequence stratigraphic architecture. Merging paleogeographic, stratigraphic and paleoecologic data, we conclude that the more abundant and diverse accumulations of large vertebrates took place in settings under the influence of coastal upwelling. A modern analogue occurs today in the Ligurian Sea, on the Tuscan offshore, where abundant nutrients carried by deep-marine currents of Western origin

Application of the authigenic 10Be/9Be dating method to Late Miocene-Pliocene sequences in the northern Danube Basin (Pannonian Basin System): Confirmation of heterochronous evolution of sedimentary environments

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Šujan, Michal; Braucher, Régis; Kováč, Michal; Bourlès, Didier L.; Rybár, Samuel; Guillou, Valéry; Hudáčková, Natália

2016-02-01

Authigenic 10Be/9Be dating method was applied to lacustrine, deltaic and alluvial sequences of the northern Danube Basin (Pannonian Basin System), to bridge the insufficiency of geochronological data for the Late Miocene to Pliocene period. The measurements of 51 samples (both lacustrine and floodplain), ranging from 11.6 to 0.95 Ma are consistent with the existing magnetostratigraphic and biostratigraphic data standing mainly on the evolution degree of endemic mollusk fauna, mammals and dinocysts. This agreement confirms our assumption that the incoming beryllium fluxes remained constant over the studied time period and thus that the two initial 10Be/9Be ratios determined in actual Holocene/Late Pleistocene sediments (lacustrine and floodplain) are valid for these environments. The obtained ages indicate gradual progradation of the deltaic depositional systems across the Danube Basin with a clear time-transgressional character, replacing basin floor and shelfal environments. Deltaic sedimentation occurred firstly in the north at foothills of the Western Carpathians from 11.0 Ma, and changed to the alluvial environment after 10.5 Ma. At the same time (~ 10.5 Ma), the paleo-Danube deltaic system draining the Eastern Alps entered the study area from the Vienna Basin situated on the West. Later, the deltaic systems were merged in the central part of the basin and reached its southeastern margin at ~ 9.4 Ma. Regression of the Lake Pannon from the southernmost part of the study area is evidenced after 8.7 Ma. Alluvial deposition of meandering rivers lasting until 6.0-5.0 Ma followed and was interrupted by the early Pliocene basin inversion. Sedimentation of braided streams took place during the late Pliocene and Pleistocene, reflecting uplift of mountains surrounding the basin margins. This study documents the powerful potential of the authigenic 10Be/9Be dating method and its reliability in a basin with complicated tectonic and sedimentary history. It demonstrates that

The role of tephra studies in African paleoanthropology as exemplified by the Sidi Hakoma Tuff

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WoldeGabriel, Giday; Endale, Tamrat; White, Tim D.; Thouveny, Nicolas; Hart, William K.; Renne, Paul R.; Asfaw, Berhane

2013-01-01

Beginning in the 1960s, geological and paleoanthropological exploration of the Ethiopian rift system's basins have led to the discovery and assembly of the most comprehensive record of human biological and technological change during the last 6 million years. The hominid fossils, including partial skeletons, were primarily discovered in the Afar Rift, the Main Ethiopian Rift, and in the Omo Basin of the broadly rifted zone of SW Ethiopia. The paleoanthropological research areas within the SW Afar Rift that have yielded many diverse hominid species and the oldest stone tools are, from north to south, Woranso-Mille (aff. Ardipithecus and Au. afarensis), Hadar (Au. afarensis, Homo sp.), Dikika (Au. afarensis), Gona (Ar. kadabba, Ar. ramidus, H. erectus, and oldest stone tools), Middle Awash (Ar. kadabba, Ar. ramidus, Au. anamensis, Au. afarensis, Au. garhi, H. erectus, H. rhodesiensis, H. sapiens idaltu, and the oldest paleo-butchery locality), and Galili (Au. afarensis). Additional hominid remains were discovered at Melka Kunture on the banks of the Awash River near its source along the western margin of the central part of the Main Ethiopian Rift (H. erectus), at Konso (H. erectus and A. boisei), and at the southern end of the MER, and in the Omo Basin (Au. anamensis, Au. afarensis, Au. aethiopicus, Au. boisei, H. habilis, and H. erectus). Distal and sometimes proximal tephra units interbedded within fossilifeous sedimentary deposits have become key elements in this work by providing chronological and correlative control and depositional contexts. Several regional tephra markers have been identified within the northern half of the eastern African rift valley in Ethiopia and Kenya, and in marine sediments of the Gulf of Aden Rift and the NW Indian Ocean. Out of the many regional tephra stratigraphic markers that range in age from the early Pliocene (3.97 Ma) to the late Pleistocene (0.16 Ma), the Sidi Hakoma Tuff (SHT) has been more widely identified and thoroughly

Can Cooler Heads Prevail?

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Rice, A. R.

2015-12-01

The significant correlation between dropping temperatures throughout the Pliocene and the concomitant explosive expansion of the Hominid brain has led a number of workers to postulate climate change drove human evolution. Our brain (that of Homo sapiens), comprises 1-2 percent of our body weight but consumes 20 -25 percent of the body's caloric intake. We are "hotheads". Brains are extremely sensitive to overheating but we are endowed with unparalleled thermal regulation, much of it given over to protecting the Central Nervous System (CNS). Will there be reversed trends with global warming? The human brain has been shrinking since the end of the Ice Ages, losing about 150cc over the past 10,000 years. Polar bear skulls have been downsizing as well. Almost all mass extinctions or evolutionary upheavals are attributed to global warming: e.g. the Permian/Triassic (P/T) event, i.e., "The Great Dying", 250 million years ago (~90% of all life forms wiped out); the Paleocene/ Eocene Thermal Maximum (PETM) 55 million years ago. They may be analogs for what might await us. Large creatures, whose body size inhibits cooling, melted away during the PETM. Horses, initially the size of dogs then, reduced to the size of cats. An unanticipated hazard for humans that may attend extreme global warming is dumbing down or needing to retreat to the Poles as did those creatures that survived the P/T event (some references: http://johnhawks.net/research/hawks-2011-brain-size-selection-holocene; Kandel, E. et al Principles of Neural Science 4th ed. New York (US): McGraw-Hill, 2000; Selective Brain Cooling in Early Hominids:phylogenetic and evolutionary implications, Reeser, H., reeser@flmnh.ufl.edu; How the body controls brain temperature; the temperature shielding effect of cerebral blood flow, Mingming Z. et al. J Appl Physiol. 2006 November; 101(5): 1481-1488; news.nationalgeographic.com/ news/2014/03/140327-climate-change-shrinks-salamanders-global-warming-science/; Heat illness and

Monitoring of incremental changes in maximum interincisal opening after gap arthroplasty omits the risk of Re-ankylosis.

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Khalifa, Ghada Amin

2018-01-01

The aim of this clinical study was to prospectively measure the incremental changes in the maximum interincisal opening (MIO) after 1 cm gap arthroplasty, compare these changes between unilateral and bilateral cases, and emphasize the importance of the monitoring of the MIO for at least 24 months. This prospective study enrolled 26 patients with TMJ ankylosis either unilateral or bilateral. The fingers assessment method was used to measure the MIO preoperatively, intraoperatively, and monthly postoperatively up to 24 months. All the patients had undergone 1 cm gap arthroplasty to release the ankylosis. The changes in MIO measurements of unilateral and bilateral cases were statistically compared. The physiotherapy was performed until the measurements had normal stable values. All the cases showed a significant decrease in MIO at the first three months. At 6 months, the MIO continuously increased up to 1 year. There was no difference between the unilateral and bilateral cases. At the end of the follow-up, all measurements showed normal stable values. The monitoring of MIO is important to detect the early signs of re-ankylosis. It is the only way that can be used in which the early signs cannot be detected in radiographs. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

A Pliocene marine diatom δ18O record of terrestrial-marine feedbacks and orbitally-paced cryogenic brine formation in the McMurdo Dry Valleys

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Dodd, J. P.; Abbott, T.; Gibbons, J. A.

2017-12-01

Orbital frequencies are well documented in a number of terrestrial and marine climate records throughout the Cenozoic; however, assessing the feedbacks and timing of terrestrial-marine systems on glacial-interglacial timescales is often challenging. This is particularly the case in high-latitude, near-shore environments where traditional proxy records like benthic foraminifera are absent. Here we present oxygen isotope (δ18O and δ17O) values from marine diatom silica in the mid-Pliocene (3.5 - 4.7Ma) section of the AND-1B core from McMurdo Sound, Antarctica. Diatom silica δ18O values range between +28.1 and +36.4‰ VSMOW. Over a range of temperatures (0 to 10°C) that reflect both growth and shallow (fall on a mixing line between marine and meteoric waters, which also supports our cryogenic brine hypothesis. The AND-1B δ18O values have an inverse relationship with the stacked benthic foraminifera δ18O record where lower δ18O values in the AND-1B diatom silica correspond with colder intervals, and we interpret variations in the diatom δ18O values as increased brine flux from the MDV to McMurdo Sound. Currently, subsurface brines in the MDV are hydrologically connected with McMurdo Sound. Density-driven transport of these brines from the MDV to the marine costal environments during the warm mid-Pliocene indicate a potentially overlooked terrestrial source of hypersaline waters. Although the lateral extent of these brines is not known, mixing between the terrestrial cryogenic brines and seawater may represent a significant flux of hypersaline water to the marine environment during warmer-than-present global conditions.

Emulation of long-term changes in global climate: application to the late Pliocene and future

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N. S. Lord

2017-11-01

Full Text Available Multi-millennial transient simulations of climate changes have a range of important applications, such as for investigating key geologic events and transitions for which high-resolution palaeoenvironmental proxy data are available, or for projecting the long-term impacts of future climate evolution on the performance of geological repositories for the disposal of radioactive wastes. However, due to the high computational requirements of current fully coupled general circulation models (GCMs, long-term simulations can generally only be performed with less complex models and/or at lower spatial resolution. In this study, we present novel long-term continuous projections of climate evolution based on the output from GCMs, via the use of a statistical emulator. The emulator is calibrated using ensembles of GCM simulations, which have varying orbital configurations and atmospheric CO2 concentrations and enables a variety of investigations of long-term climate change to be conducted, which would not be possible with other modelling techniques on the same temporal and spatial scales. To illustrate the potential applications, we apply the emulator to the late Pliocene (by modelling surface air temperature – SAT, comparing its results with palaeo-proxy data for a number of global sites, and to the next 200 kyr (thousand years (by modelling SAT and precipitation. A range of CO2 scenarios are prescribed for each period. During the late Pliocene, we find that emulated SAT varies on an approximately precessional timescale, with evidence of increased obliquity response at times. A comparison of atmospheric CO2 concentration for this period, estimated using the proxy sea surface temperature (SST data from different sites and emulator results, finds that relatively similar CO2 concentrations are estimated based on sites at lower latitudes, whereas higher-latitude sites show larger discrepancies. In our second illustrative application, spanning the next

The early Pleistocene deciduous hominid molar FS-72 from the Sangiran Dome of Java, Indonesia: A taxonomic reappraisal based on its comparative endostructural characterization.

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Zanolli, Clément; Grine, Frederick E; Kullmer, Ottmar; Schrenk, Friedemann; Macchiarelli, Roberto

2015-08-01

Among the ten fossil hominid deciduous teeth reported so far from the Pleistocene sediments of the Sangiran Dome of Java are two isolated lower second molars: specimens PCG.2 from the Kabuh Formation and FS-72 from the Pucangan Formation. While PCG.2 appears to be certainly attributable to Homo erectus, FS-72 is somewhat more problematic, even though it is commonly listed within the Indonesian H. erectus hypodigm. Largely because of its large size, it was originally attributed to Meganthropus paleojavanicus. Subsequent study highlighted a set of metric and nonmetric crown features also found in Australopith and African early Homo (notably H. habilis) homologues. An additional problem with the taxonomic assignment of isolated teeth from the Pleistocene of Java is the presence of Pongo in these same deposits. To assess the taxonomic affinity of FS-72, we investigated its inner structure (tissue proportions and enamel-dentine junction morphology) by using techniques of 2-3D virtual imaging coupled with geometric morphometric analyses. The results show that FS-72 has thinner enamel compared to fossil and recent humans and that its topographic repartition more closely follows the pongine pattern. It also exhibits a Pongo-like elongated morphology of the enamel-dentine junction, with proportionally lower and mesiodistally spaced dentine horns. Given the morphological and metric similarities between fossil orangutan and H. erectus molars, we tested the hypothesis that its internal morphology more closely resembles the patterns evinced by PCG.2 and modern humans than Pongo. Accordingly, we consider that FS-72 more likely represents a dm2 of Pongo rather than Homo. © 2015 Wiley Periodicals, Inc.

Sedimentology and Palynostratigraphy of a Pliocene-Pleistocene (Piacenzian to Gelasian) deposit in the lower Negro River: Implications for the establishment of large rivers in Central Amazonia

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Soares, Emílio Alberto Amaral; D'Apolito, Carlos; Jaramillo, Carlos; Harrington, Guy; Caputo, Mario Vicente; Barbosa, Rogério Oliveira; Bonora dos Santos, Eneas; Dino, Rodolfo; Gonçalves, Alexandra Dias

2017-11-01

The Amazonas fluvial system originates in the Andes and runs ca. 6700 km to the Atlantic Ocean, having as the main affluent the Negro River (second largest in water volume). The Amazonas transcontinental system has been dated to the late Miocene, but the timing of origin and evolutionary processes of its tributaries are still poorly understood. Negro River alluvial deposits have been dated to the middle to late Pleistocene. Recently, we studied a number of boreholes drilled for the building of a bridge at the lower course of the Negro River. A thin (centimetric) sedimentary deposit was found, laterally continuous for about 1800 m, unconformably overlaying middle Miocene strata and unconformably overlain by younger Quaternary deposits. This deposit consists predominantly of brownish-gray sandstones cemented by siderite and with subordinate mudstone and conglomerate beds. Palynological, granulometric, textural and mineralogical data suggest that the initial Negro River aggradation took place in the deep incised valley under anoxic conditions and subsequently along the floodplain, with efficient transport of mixed origin particles (Andean and Amazonic). Angiosperm leaves, wood and pollen are indicative of a tropical continental palaeoenvironment. A well preserved palynoflora that includes Alnipollenites verus, Grimsdalea magnaclavata and Paleosantalaceaepites cingulatus suggests a late Pliocene to early Pleistocene (Piacenzian to Gelasian) age for this unit, which was an age yet unrecorded in the Amazon Basin. These results indicate that by the late Pliocene-early Pleistocene, large scale river activity was occurring in Central Amazonia linking this region with the Andean headwaters, and therefore incompatible with Central Amazonia barriers like the Purus arch.

Stratigraphy of the Koobi Fora Formation (Pliocene and Pleistocene) in the Ileret region of northern Kenya

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Gathogo, Patrick N.; Brown, Francis H.

2006-08-01

Exposures of Pliocene and Pleistocene deposits in the Ileret region include all eight members of the Koobi Fora Formation and represent at least 533 m of section from the base of the Lonyumun Member to the top of the Chari Mb. This thickness is more than twice that reported by earlier workers (˜260 m) and compares well with the composite section of the Koobi Fora Formation (525 m). Thus the Ileret region provides a very complete and representative outcrop of the Koobi Fora Formation. As Koobi Fora Formation member boundaries are placed at the base of specified tuffs, not all member boundaries can be recognized in the Ileret region. For this reason, the stratigraphy is described in terms of the following members (thicknesses in parentheses): Lonyumun (110 m), undifferentiated Moiti and Lokochot (104 m), Tulu Bor (54 m), Burgi (55 m), KBS (74 m), Okote (45 m), and Chari (93 m). Moreover, the boundary between the Okote Member and the KBS Member in the Ileret region is placed at a prominent caliche which must closely approximate the age of the Okote Tuff in its type section.

Interhemispheric teleconnections: Late Pliocene change in Mediterranean outflow water linked to changes in Indonesian Through-Flow and Atlantic Meridional Overturning Circulation, a review and update

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Sarnthein, Michael; Grunert, Patrick; Khélifi, Nabil; Frank, Martin; Nürnberg, Dirk

2018-03-01

The ultimate, possibly geodynamic control and potential impact of changes in circulation activity and salt discharge of Mediterranean outflow waters (MOW) on Atlantic meridional overturning circulation have formed long-standing objectives in paleoceanography. Late Pliocene changes in the distal advection of MOW were reconstructed on orbital timescales for northeast Atlantic DSDP/ODP sites 548 and 982 off Brittany and on Rockall Plateau, supplemented by a proximal record from Site U1389 west off Gibraltar, and compared to Western Mediterranean surface and deep-water records of Alboran Sea Site 978. From 3.43 to 3.3 Ma, MOW temperatures and salinities form a prominent rise by 2-4 °C and 3 psu, induced by a preceding and coeval rise in sea surface and deep-water salinity and increased summer aridity in the Mediterranean Sea. We speculate that these changes triggered an increased MOW flow and were ultimately induced by a persistent 2.5 °C cooling of Indonesian Through-Flow waters. The temperature drop resulted from the northward drift of Australia that crossed a threshold value near 3.6-3.3 Ma and led to a large-scale cooling of the eastern subtropical Indian Ocean and in turn, to a reduction of African monsoon rains. Vice versa, we show that the distinct rise in Mediterranean salt export after 3.4 Ma induced a unique long-term rise in the formation of Upper North Atlantic Deep Water, that followed with a phase lag of 100 ky. In summary, we present evidence for an interhemispheric teleconnection of processes in the Indonesian Gateways, the Mediterranean and Labrador Seas, jointly affecting Pliocene climate.

Punctuated Sediment Discharge during Early Pliocene Birth of the Colorado River: Evidence from Regional Stratigraphy, Sedimentology, and Paleontology

Science.gov (United States)

Dorsey, Rebecca J.; O'Connell, Brennan; McDougall, Kristin; Homan, Mindy B.

2018-01-01

discharge are assessed by comparing the depositional chronology to the record of global sea-level change. The lower Colorado River Valley and Salton Trough experienced marine transgression during a gradual fall in global sea level between 6.3 and 5.5 Ma, implicating tectonic subsidence as the main driver of latest Miocene relative sea-level rise. A major fall of global sea level at 5.3 Ma outpaced subsidence and drove regional delta progradation, earliest flushing of Colorado River sand into the northern Gulf of California, and erosion of Bouse basal carbonate and siliciclastic members. The lower Colorado River valley was re-flooded by shallow marine waters during smaller changes in global sea level 5.1-4.8 Ma, after the river first ran through it, which requires a mechanism to stop delivery of sand to the lower river valley. We propose that tectonically controlled subsidence along the lower Colorado River, upstream of the southern Bouse study area, temporarily trapped sediment and stopped delivery of sand to the lower river valley and northern Gulf of California for 200-300 kyr. Massive progradation of the fluvial-deltaic system back down the river valley into the Salton Trough starting 4.8-4.5 Ma apparently was driven by a huge increase in sediment discharge that overwhelmed the sediment-storage capacity of sub-basins along the lower river corridor and established the fully integrated river channel network. Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology". Accompanies Dorsey et al. "Punctuated sediment discharge during early Pliocene birth of the Colorado River: Evidence from regional stratigraphy, sedimentology, and paleontology".

The fossil record as a tool in cyclo stratigraphy: the incidence of Milankovitch-scale palaeoenvironmental changes on palaeocommunities

Energy Technology Data Exchange (ETDEWEB)

Rodriguez-Tovar, F. J.

2013-06-01

Cyclo stratigraphic analysis at the Milankovitch scale has to date mainly been approached through the sedimentary record, although palaeontological data (the fossil record) is known to provide useful evidence of orbital-scale cycles of precession, obliquity and eccentricity. Orbit ally induced marine and terrestrial palaeoenvironmental changes determine variable responses on the part of the resident communities. Aside from the disruption of communities, complex evolutionary responses including stasis, speciation and extinction phenomena may take place. Cyclic variations in the marine past-biota at the community level, or in some particular taxa, have often been associated with orbit ally induced changes in palaeoenvironmental parameters. Cyclo stratigraphic research into foraminifera, radiol aria and nanno fossil data, mainly from Cretaceous sediments, may contribute significantly to our understanding of the planktonic community's response, whereas the response of the benthic community, deriving mainly from benthic foraminifera and trace fossils, has been studied to a lesser extent. Recognition of Milankovitch cycles from terrestrial palaeocommunities is relatively scarce and based mainly on the study of Pliocene-Miocene pollen assemblages. Astronomical forced climate changes determine well known variations in the distribution of terrestrial vegetation, but can also affect the terrestrial animal community, including hominid populations (migration, dispersion and colonisation). (Author)

The Once and Future North Atlantic: How the Mid-Pliocene Warm Period Can Increase Stakeholder Preparedness in a Warming World

Science.gov (United States)

Jacobs, P.; de Mutsert, K.

2013-12-01

Paleoclimatic reconstructions, particularly from periods that may serve as an analog to the present and future greenhouse-driven warming, are increasingly being used to validate climate models as well as to provide constraints on broad impacts such as global temperature and sea level change. However, paleoclimatic data remains under-utilized in decision-making processes by stakeholders, who typically rely on scenarios produced by computer models or naive extrapolation of present trends. We hope to increase the information available to stakeholders by incorporating paleoclimatic data from the mid-Pliocene Warm Period (mPWP, ~3ma) into a fisheries model of the North Atlantic. North Atlantic fisheries are economically important and are expected to be sensitive to climatic change. State of the art climate models remain unable to realistically simulate the North Atlantic, both over the observational record as well as during times in the geologic past such as the mPWP. Given that the mPWP shares many of the same boundary conditions as those likely to be seen in the near future, we seek to answer the question 'What if the climate of the future looks more like the climate of the past?' relative to what state of the art computer models currently project. To that end we have created a suite of future North Atlantic Ocean scenarios using output from the CMIP3 and CMIP5 modeling experiments, as well as the PRISM group's Mid-Pliocene ocean reconstruction. We use these scenarios to drive an ecosystem-based fisheries model using the Ecopath with Ecosim (EwE) software to identify differences between the scenarios as the North Atlantic Ocean changes through time. Additionally, we examine the spatial component of these differences by using the Ecospace module of EwE. Whereas the Ecosim realizations are intended to capture the dynamic response to changing oceanographic parameters (SST, SSS, DO) over time, the Ecospace experiments are intended to explore the impact of different

(U-Th)/He thermochronometric constraints on the late Miocene-Pliocene northern Cordillera Real, tectonic development of the northern Cordillera Real, tectonic development of the Interandean Depression, the Spikings, Ecuador.

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Spikings, R. A.; Crowhurst, P. V.

2004-12-01

The low sensitivity of apatite fission track (AFT) thermochronometry at temperatures less than ˜60 °C suggests that AFT data sets from the Andean Cordilleras may have frequently failed to identify specific periods after 9 Ma when cooling rates were high. Forward modeling of (U-Th)/He apatite age data obtained from the juxtaposed Paleozoic-Mesozoic Alao, Loja, and Salado terranes in the northern Cordillera Real, Ecuador, has improved the resolution of previous AFT thermal histories for the past 9 My. The Alao and Loja terranes form a coherent, structural block that resided at temperatures greater than 70-80 °C until ˜3.3-2.8 Ma and then cooled rapidly to less than 40 °C at rates of >15 °C/My. Intraterrane variations in the cooling and exhumation histories in the Salado terrane suggest that nonterrane-bounding faults played a significant role during its Pliocene-Recent evolution. The Salado terrane preserves an older history that reveals elevated cooling rates during 22-19 and 18-15 Ma. Subsequently, the terrane cooled rapidly from greater than 90 °C to less than 40 °C during 11-8 and 5.5-3.5 Ma at rates of >8 °C/My. Vertical reactivation of the Llanganates fault, which separates the Salado and Loja terranes, during the Pliocene-Recent coincides with the main stages of formation of the juxtaposed Interandean Depression, which provides further constraints on the growth phases of the depression and the Cordillera.

Insights into the quality of DnaA boxes and their cooperativity

DEFF Research Database (Denmark)

Hansen, Flemming G.; Christensen, Bjarke Bak; Nielsen, Christina Bang

2006-01-01

Plasmids carrying the mioC promoter region with its two DnaA boxes are as efficient in titration of DnaA protein as plasmids carrying a replicationinactivated oriC region with its five DnaA boxes. The two DnaA boxes upstream of the mioC promoter were mutated in various ways to study the cooperati......Plasmids carrying the mioC promoter region with its two DnaA boxes are as efficient in titration of DnaA protein as plasmids carrying a replicationinactivated oriC region with its five DnaA boxes. The two DnaA boxes upstream of the mioC promoter were mutated in various ways to study...... the cooperativity between the DnaA boxes, and to study in vivo the in vitrodefined 9mer DnaA box consensus sequence TTA/TTNCACA). The quality and cooperativity of the DnaA oxes were determined in two complementary ways: as titration of DnaA protein leading to derepression of the dnaA promoter, and as repression...... of the mioC promoter caused by the DnaA protein binding to the DnaA boxes. Titration of DnaA protein correlated with repression of the mioC promoter. The level of titration and repression with the normal promoter-proximal box (TTTTCCACA) depends strongly on the presence and the quality of a DnaA box...

Mid-Pliocene to Early Pleistocene land and sea surface temperature history of NW Australia based on organic geochemical proxies

Science.gov (United States)

Smith, R. A.; Castañeda, I. S.; Henderiks, J.; Christensen, B. A.; De Vleeschouwer, D.; Renema, W.; Groeneveld, J.; Bogus, K.; Gallagher, S. J.; Fulthorpe, C.; Expedition 356 Scientists, I.

2017-12-01

IODP Expedition 356 Site U1463 is located off the coast of NW Australia, and is sensitive to Indonesian Throughflow (ITF) variability. The ITF is a critical ocean gateway that affects global thermohaline circulation, and regulates the movement of water from the Pacific Ocean into the Indian Ocean. However, despite its importance to the global climate system, few SST reconstructions exist for this region that span the Plio-Pleistocene. Here we investigate both the land and sea-surface temperature (SST) history of NW Australia to constrain ITF variability across the Plio-Pleistocene interval. We apply multiple organic geochemical proxies to this site from 3.4-2.6 Ma, which includes the mid-Pliocene warm period, characterized by slightly higher (2-3°C) global temperatures and similar CO2 concentrations to modern values (e.g. Badger et al. 2013; Bartoli et al., 2011; Dowsett et al., 2009; Hönisch et al., 2009; Pagani et al. 2009; Raymo et al., 1996). SST was reconstructed using TEX86, based on isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs), and the long-chain diol index (LDI), based on the ratio of diols produced by marine diatoms (Rampen et al., 2012). The Uk'37 index, based on long-chain ketones, was analyzed but cannot be applied as a SST proxy at this site due to the influence of coastal alkenone producers. Additionally, a continental air temperature record was developed using the MBT'5ME proxy, based on branched GDGTs (De Jonge et al., 2014; Weijers et al., 2007). We find that TEX86, LDI and MBT'5Me exhibit similar trends and show relatively warm and stable temperatures from 3.5-2.4 Ma followed by a gradual cooling of 3-4°C from 2.4-1.5 Ma. This cooling corresponds with an arid interval previously identified on the same core by Christensen et al. (2017). Furthermore, we find that the TEX86 record agrees closely with the LR04 global benthic δ18O stack (Lisiecki and Raymo, 2005) and captures glacial/interglacial periods including Marine Isotope Stage

Millennial-scale Climate Variations Recorded As Far Back As The Early Pliocene

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Steenbrink, J.; Hilgen, F. J.; Lourens, L. J.

Quaternary climate proxy records show compelling evidence for climate variability on time scales of a few thousand years. The causes for these millennial-scale or sub- Milankovitch cycles are yet poorly understood, not in the least due to the complex feedback mechanisms of large ice-sheets during the Quaternary. We present evidence of millennial-scale climate variability in Early Pliocene lacustrine sediments from the intramontane Ptolemais Basin in northwestern Greece. The sediments are well ex- posed in a series of open-pit lignite mines and exhibit a distinct m-scale sedimentary cyclicity of alternating lignites and lacustrine marl beds that result from precession- induced variations in climate. A higher-frequency cyclicity is particular prominent within the marl segment of individual cycles. A stratigraphic interval of~115 kyr, cov- ering five precession-induced sedimentary cycles, was studied in nine parallel sections from two quarries located several km apart. Colour reflectance records were used to quantify the within-cycle variability and to determine its lateral continuity. Much of the within-cycle variability could be correlated between the parallel sections, even in fine detail, which suggests that these changes reflect basin-wide variations in environ- mental conditions related to (regional) climate fluctuations. Interbedded volcanic ash beds demonstrate the synchronicity of these fluctuations and spectral analysis of the reflectance time series shows a significant concentration of variability at periods of ~11,~5.5 and~2 kyr. Their occurrence at times before the intensification of the North- ern Hemisphere glaciation suggests that they cannot solely have resulted from internal ice-sheet dynamics. Possible candidates include harmonics or combination tones of the main orbital cycles, variations in solar output or periodic motions of the Earth and moon.

Mothering From the Inside Out: Results of a second randomized clinical trial testing a mentalization-based intervention for mothers in addiction treatment.

Science.gov (United States)

Suchman, Nancy E; DeCoste, Cindy L; McMahon, Thomas J; Dalton, Rachel; Mayes, Linda C; Borelli, Jessica

2017-05-01

Mothers with histories of alcohol and drug addiction have shown greater difficulty parenting young children than mothers with no history of substance misuse. This study was the second randomized clinical trial testing the efficacy of Mothering From the Inside Out (MIO), a 12-week mentalization-based individual therapy designed to address psychological deficits commonly associated with chronic substance use that also interfere with the capacity to parent young children. Eighty-seven mothers caring for a child between 11 and 60 months of age were randomly assigned to receive 12 sessions of MIO versus 12 sessions of parent education (PE), a psychoeducation active control comparison. Maternal reflective functioning, representations of caregiving, mother-child interaction quality, and child attachment were evaluated at baseline and posttreatment and 3-month follow-up. Mother-child interaction quality was assessed again at 12-month follow-up. In comparison with PE mothers, MIO mothers demonstrated a higher capacity for reflective functioning and representational coherence at posttreatment and 3-month follow-up. At 12-month follow-up, compared to PE cohorts, MIO mothers demonstrated greater sensitivity, their children showed greater involvement, and MIO dyads showed greater reciprocity. As addiction severity increased, MIO also appeared to serve as a protective factor for maternal reflective functioning, quality of mother-child interactions, and child attachment status. Results demonstrate the promise of mentalization-based interventions provided concomitant with addiction treatment for mothers and their young children.

Mothering from the Inside Out: Results of a second randomized clinical trial testing a mentalization-based intervention for mothers in addiction treatment

Science.gov (United States)

Suchman, Nancy E.; DeCoste, Cindy L.; McMahon, Thomas J.; Dalton, Rachel; Mayes, Linda C.; Borelli, Jessica

2016-01-01

Mothers with histories of alcohol and drug addiction have shown greater difficulty parenting young children than mothers with no history of substance misuse. This study was the second randomized clinical trial testing the efficacy of Mothering from the Inside Out (MIO), a 12-week mentalization-based individual therapy designed to address psychological deficits commonly associated with chronic substance use that also interfere with the capacity to parent young children. Eighty-seven mothers caring for a child between 11 and 60 months of age were randomly assigned to receive 12 sessions of MIO versus 12 sessions of Parent Education (PE)—a psychoeducation active control comparison. Maternal reflective functioning, representations of caregiving, mother-child interaction quality, and child attachment were evaluated at baseline and post-treatment and 3-month follow up. Mother-child interaction quality was assessed again at 12-month follow up. In comparison with PE mothers, MIO mothers demonstrated a higher capacity for reflective functioning and representational coherence at post-treatment and 3-month follow up. At 12-month follow up, compared to PE cohorts, MIO mothers demonstrated greater sensitivity, their children showed greater involvement, and MIO dyads showed greater reciprocity. As addiction severity increased, MIO also appeared to serve as a protective factor for maternal reflective functioning, quality of mother-child interactions, and child attachment status. Results demonstrate the promise of mentalization-based interventions provided concomitant with addiction treatment for mothers and their young children. PMID:28401850

Late Pleistocene acceleration of deformation across the northern Tianshan piedmont (China) evidenced from the morpho-tectonic evolution of the Dushanzi anticline

Science.gov (United States)

Charreau, Julien; Saint-Carlier, Dimitri; Lavé, Jérôme; Dominguez, Stéphane; Blard, Pierre-Henri; Avouac, Jean-Philippe; Brown, Nathan D.; Malatesta, Luca Claude; Wang, Shengli; Rhodes, Edward J.

2018-04-01

We document the temporal evolution of deformation in the northern Tianshan piedmont where the deformation is partitioned across several thrusts and folds. We focus on the Dushanzi anticline, where abandoned terraces and growth strata allow us to constrain the history of folding since the Miocene. Based on subsurface seismic imaging, structural measurements and morphological analysis, we show that this anticline is associated with two decollement levels. We use kink band migration in growth strata dated by paleomagnetism to constrain the shortening from the Mio-Pliocene to the Holocene. Our results show that the Dushanzi anticline has been active since at least 8 Ma and that the fold grew at a steady shortening rate of 0.6 ± 0.1 mm/yr from 8 to 1.5 Ma with possible variations from 2.5 to 1.5 Ma. Then it accelerated rapidly to a rate of 4.3 ± 1.0 mm/yr over at least the last 100 ka. These results, together with similar temporal shortening evolutions across other structures, suggest that the deformation rate across the eastern Tianshan piedmont increased relatively recently. This may reflect either a redistribution of the deformation from the internal structures toward the borders or a general acceleration of the deformation across the entire range.

Autogenic Versus Allogenic Controls on the Evolution of a Coupled Fluvial Megafan-Mountainous Catchment System: Insight from Numerical Modelling

Science.gov (United States)

Mouchene, M.; van der Beek, P.; Carretier, S.; Mouthereau, F.

2017-12-01

Alluvial megafans are sensitive recorders of landscape evolution, controlled by both autogenic processes and allogenic forcing, and they are influenced by the coupled dynamics of the fan with its mountainous catchment. The Mio-Pliocene Lannemezan megafan in the northern Pyrenean foreland (SW France) was abandoned by its mountainous feeder stream during the Quaternary and subsequently incised. The flight of alluvial terraces abandoned along the stream network may suggest a climatic control on the incision. We use a landscape evolution numerical model (CIDRE) to explore the relative roles of autogenic processes and external forcing in the building, abandonment and incision of a foreland megafan, and we compare the results with the inferred evolution of the Lannemezan megafan. Autogenic processes are sufficient to explain the building of a megafan and the long-term entrenchment of its feeding river on time and space scales that match the Lannemezan setting. Climate, through temporal variations in precipitation rate, may have played a role in the episodic pattern of incision on a shorter timescale. In contrast, base-level changes, tectonic activity in the mountain range or tilting of the foreland through flexural isostatic rebound do not appear to have played a role in the abandonment of the megafan.

Impact of climate changes during the last 5 million years on groundwater in basement aquifers.

Science.gov (United States)

Aquilina, Luc; Vergnaud-Ayraud, Virginie; Les Landes, Antoine Armandine; Pauwels, Hélène; Davy, Philippe; Pételet-Giraud, Emmanuelle; Labasque, Thierry; Roques, Clément; Chatton, Eliot; Bour, Olivier; Ben Maamar, Sarah; Dufresne, Alexis; Khaska, Mahmoud; Le Gal La Salle, Corinne; Barbecot, Florent

2015-09-22

Climate change is thought to have major effects on groundwater resources. There is however a limited knowledge of the impacts of past climate changes such as warm or glacial periods on groundwater although marine or glacial fluids may have circulated in basements during these periods. Geochemical investigations of groundwater at shallow depth (80-400 m) in the Armorican basement (western France) revealed three major phases of evolution: (1) Mio-Pliocene transgressions led to marine water introduction in the whole rock porosity through density and then diffusion processes, (2) intensive and rapid recharge after the glacial maximum down to several hundred meters depths, (3) a present-day regime of groundwater circulation limited to shallow depth. This work identifies important constraints regarding the mechanisms responsible for both marine and glacial fluid migrations and their preservation within a basement. It defines the first clear time scales of these processes and thus provides a unique case for understanding the effects of climate changes on hydrogeology in basements. It reveals that glacial water is supplied in significant amounts to deep aquifers even in permafrosted zones. It also emphasizes the vulnerability of modern groundwater hydrosystems to climate change as groundwater active aquifers is restricted to shallow depths.

Mixed carbonate-siliciclastic sedimentation on a tectonically active margin: Example from the Pliocene of Baja California Sur, Mexico

Science.gov (United States)

Dorsey, Rebecca J.; Kidwell, Susan M.

1999-10-01

Bioclast-rich, coarse-grained deposits in the Pliocene Loreto basin provide a record of mixed carbonate and siliciclastic sedimentation at the steep hanging-wall margin of this small, fault-controlled basin. Sedimentary facies consist of sand- to gravel-sized carbonate debris mixed with volcaniclastic sand and gravel in a proximal to distal facies tract that includes matrix-rich and matrix-poor shelly conglomerate, impure calcirudite and calcarenite, mixed-composition turbidites, and bioturbated calcarenitic sandstone. Carbonate material was produced by mollusks and other benthic organisms on a narrow, high-energy shelf and mixed with volcaniclastic sand and gravel in cross-shelf channels. These mixtures were transported down a steep subaqueous slope by debris flows, grain flows, and turbidity currents, forming foresets and bottomsets of marine Gilbert-type deltas. This style of mixed carbonate-siliciclastic sedimentation has not been documented in detail elsewhere but should be locally abundant in the stratigraphic record of fault-bounded basins, particularly those with cool or nutrient-rich waters that support relatively few binding and framework-building faunas. Recognition of similar facies in other settings can provide useful insights into ancient conditions of carbonate production, oceanography, climate, and tectonics.

The origin of volcanic rock fragments in Upper Pliocene Grad Member of the Mura Formation, North-Eastern Slovenia

Directory of Open Access Journals (Sweden)

Polona Kralj

2006-12-01

Full Text Available Fresh-water, coarse-grained and detritus-dominated Mura Formation in North Eastern Slovenia includes pyroclastic and volcaniclastic deposits originating from Upper Pliocene volcanic activity of basaltic geochemical character. Although localized in occurrence at the hamlet Grad, these pyroclastic and volcaniclastic sediments forma distinctive depositional unit, for which the term “Grad Member” is proposed and introduced in this paper.In the Grad area no lavas or cinder cones are preserved, and the origin of volcaniclastic fragments still uncertain. For this reason, chemical composition of basaltic rock fragments from the Grad Member volcaniclastics has been studied and compared with basaltic rocks from the neighboring locations at Klöch, Kindsberg, Dölling and Neuhaus. The Grad Member pyroclastic and volcaniclastic deposits seem to be fed from the same source which is different from the occurrences in Austria. That supports the idea about the existence of a local volcanic centre in the present Grad area. The old volcanic edificeswerepossiblydestroyed by the late-stage hydrovolcanic eruptions, and pyroclastic and volcaniclastic deposits subjected to constant reworking by fluvial currents in a dynamic sedimentary environment of alluvial fan and braided river systems.

Examining time trends in the Oldowan technology at Beds I and II, Olduvai Gorge.

Science.gov (United States)

Kimura, Yuki

2002-09-01

The lithic analysis of the Bed I and II assemblages from Olduvai Gorge reveals both static and dynamic time trends in early hominids' technology from 1.8 to 1.2 m.y.a. The Bed I Oldowan (1.87-1.75 m.y.a.) is characterized by the least effort strategy in terms of raw material exploitation and tool production. The inclusion of new raw material, chert, for toolmaking in the following Developed Oldowan A (DOA, 1.65-1.53 m.y.a.) facilitated more distinctive and variable flaking strategies depending on the kind of raw materials. The unique characters of DOA are explainable by this raw material factor, rather than technological development of hominids. The disappearance of chert in the subsequent Developed Oldowan B and Acheulian (1.53-1.2 m.y.a.) necessitated a shift in tool production strategy more similar to that of Bed I Oldowan than DOA. However, the evidence suggests that Bed II hominids might have been more skillful toolmakers, intensive tool-users, and engaged in more active transport of stone tools than the Bed I predecessors. Koobi Fora hominids maintained a more static tool-using behavior than their Olduvai counterparts due mainly to a stable supply of raw materials. They differed from Olduvai hominids in terms of less battering of cores, consistent transport behavior, and few productions of side-struck flakes, indicating a regional variation of toolmaking and using practice. However, they shared with Olduvai hominids a temporal trend toward the production of larger flakes from larger cores after 1.6 m.y.a. Increased intake of animal resources and the expansion of ranging area of Homo ergaster would have led to the development of technological organization. Technological changes in the Oldowan industry are attested at Olduvai Gorge, Koobi Fora, and Sterkfontein, suggesting that it was a pan-African synchronous phenomenon, beginning at 1.5 m.y.a.

Magnetostratigraphy of the Koobi Fora Formation, Lake Turkana, Kenya

Science.gov (United States)

Hillhouse, J. W.; Cerling, T. E.; Brown, F. H.

1986-10-01

The Koobi Fora Formation, a Pliocene and Pleistocene sequence of sedimentary deposits northeast of Lake Turkana, has yielded numerous fossils and stone artifacts of early hominids. Stratigraphic correlation of the hominid-bearing deposits throughout the Turkana region was established primarily by the chemistry and isotopic ages of volcanic tuffs and complemented by magnetostratigraphic studies. We have reinterpreted previously published magnetostratigraphy from the upper part of the Koobi Fora Formation because the original stratigraphy and dating of tuffs have been revised. In our reinterpretation we include previously unpublished data from the uppermost part of the formation. The upper magnetozones correlate with parts of the Brunhes Normal-Polarity Chron and Matuyama Reversed-Polarity Chron (about 0.6-0.85 Ma) and are separated from the magnetozones of the upper part of the Matuyama (2.0-1.25 Ma) by a disconformity. The Olduvai Normal-Polarity Subchron is represented within the Matuyama, but the lower part of the Matuyama (2.4-2.0 Ma) is missing due to an erosional disconformity. We have also determined magnetozones in the lower part of the Koobi Fora Formation, which had not been sampled for paleomagnetism during the earlier studies. Our time calibration of the magnetozones is made possible by isotopic dating of several tuffs and by chemical correlation of Koobi Fora tuffs with dated tuffs in the Shungura Formation of southern Ethiopia. The tephra correlations are corroborated by the excellent concordance between the magnetostratigraphies of the Koobi Fora and Shungura formations. The lower part of the Koobi Fora spans the interval from about 4 Ma to 2.4 Ma, within the Gilbert Reversed-Polarity and Gauss Normal-Polarity chrons. Rock magnetic studies indicate that detrital magnetite carries most of the stable remanence, although hematite contributes to the remanence as indicated by thermal demagnetization. The hematite, which presumably formed by

Investigating Music Information Objects

Science.gov (United States)

Weissenberger, Lynnsey K.

2016-01-01

This dissertation, titled "Investigating Music Information Objects," is a study of the nature, description, representations, and ideas related to music information objects (MIOs). This research study investigates how music practitioners from various traditions describe and conceptualize MIOs, using a theoretical framework to classify…

Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

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Robert W Boessenecker

Full Text Available Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings.Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies.Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical processes. The strong physical control on marine vertebrate preservation and preservational bias within the Purisima Formation has implications for paleoecologic and paleobiologic studies of marine vertebrates. Evidence of preservational bias among marine vertebrates suggests that careful consideration of taphonomic overprint must be undertaken before meaningful paleoecologic interpretations of shallow marine vertebrates is attempted.

Comparative taphonomy, taphofacies, and bonebeds of the Mio-Pliocene Purisima Formation, central California: strong physical control on marine vertebrate preservation in shallow marine settings.

Science.gov (United States)

Boessenecker, Robert W; Perry, Frank A; Schmitt, James G

2014-01-01

Taphonomic study of marine vertebrate remains has traditionally focused on single skeletons, lagerstätten, or bonebed genesis with few attempts to document environmental gradients in preservation. As such, establishment of a concrete taphonomic model for shallow marine vertebrate assemblages is lacking. The Neogene Purisima Formation of Northern California, a richly fossiliferous unit recording nearshore to offshore depositional settings, offers a unique opportunity to examine preservational trends across these settings. Lithofacies analysis was conducted to place vertebrate fossils within a hydrodynamic and depositional environmental context. Taphonomic data including abrasion, fragmentation, phosphatization, articulation, polish, and biogenic bone modification were recorded for over 1000 vertebrate fossils of sharks, bony fish, birds, pinnipeds, odontocetes, mysticetes, sirenians, and land mammals. These data were used to compare both preservation of multiple taxa within a single lithofacies and preservation of individual taxa across lithofacies to document environmental gradients in preservation. Differential preservation between taxa indicates strong preservational bias within the Purisima Formation. Varying levels of abrasion, fragmentation, phosphatization, and articulation are strongly correlative with physical processes of sediment transport and sedimentation rate. Preservational characteristics were used to delineate four taphofacies corresponding to inner, middle, and outer shelf settings, and bonebeds. Application of sequence stratigraphic methods shows that bonebeds mark major stratigraphic discontinuities, while packages of rock between discontinuities consistently exhibit onshore-offshore changes in taphofacies. Changes in vertebrate preservation and bonebed character between lithofacies closely correspond to onshore-offshore changes in depositional setting, indicating that the dominant control of preservation is exerted by physical processes. The strong physical control on marine vertebrate preservation and preservational bias within the Purisima Formation has implications for paleoecologic and paleobiologic studies of marine vertebrates. Evidence of preservational bias among marine vertebrates suggests that careful consideration of taphonomic overprint must be undertaken before meaningful paleoecologic interpretations of shallow marine vertebrates is attempted.

Fault Slip Partitioning in the Eastern California Shear Zone-Walker Lane Belt: Pliocene to Late Pleistocene Contraction Across the Mina Deflection

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Lee, J.; Stockli, D.; Gosse, J.

2007-12-01

Two different mechanisms have been proposed for fault slip transfer between the subparallel NW-striking dextral- slip faults that dominant the Eastern California Shear Zone (ECSZ)-Walker Lane Belt (WLB). In the northern WLB, domains of sinistral-slip along NE-striking faults and clockwise block rotation within a zone of distributed deformation accommodated NW-dextral shear. A somewhat modified version of this mechanism was also proposed for the Mina deflection, southern WLB, whereby NE-striking sinistral faults formed as conjugate faults to the primary zone of NW-dextral shear; clockwise rotation of the blocks bounding the sinistral faults accommodated dextral slip. In contrast, in the northern ECSZ and Mina deflection, domains of NE-striking pure dip-slip normal faults, bounded by NW-striking dextral-slip faults, exhibited no rotation; the proposed mechanism of slip transfer was one of right-stepping, high angle normal faults in which the magnitude of extension was proportional to the amount of strike-slip motion transferred. New geologic mapping, tectonic geomorphologic, and geochronologic data from the Queen Valley area, southern Mina deflection constrain Pliocene to late Quaternary fault geometries, slip orientations, slip magnitudes, and slip rates that bear on the mechanism of fault slip transfer from the relatively narrow northern ECSZ to the broad deformation zone that defines the Mina deflection. Four different fault types and orientations cut across the Queen Valley area: (1) The NE-striking normal-slip Queen Valley fault; (2) NE-striking sinistral faults; (3) the NW-striking dextral Coyote Springs fault, which merges into (4) a set of EW-striking thrust faults. (U-Th)/He apatite and cosmogenic radionuclide data, combined with magnitude of fault offset measurements, indicate a Pliocene to late Pleistocene horizontal extension rate of 0.2-0.3 mm/yr across the Queen Valley fault. Our results, combined with published slip rates for the dextral White Mountain

Molecular phylogenetics of the glass frog Hyalinobatrachium orientale (Anura: Centrolenidae): evidence for Pliocene connections between mainland Venezuela and the island of Tobago.

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Jowers, Michael J; Lehtinen, Richard M; Downie, Roger J; Georgiadis, Andrew P; Murphy, John C

2015-08-01

The presence of Hyalinobatrachium orientale in Tobago and in northeastern Venezuela is puzzling as this species is unknown from the island of Trinidad, an island often hypothesized to be a stepping-stone for the mainland fauna to colonize Tobago. A period of extended isolation on Tobago could result in the Hyalinobatrachium population becoming distinct from the mainland H. orientale. Here, we use 12S and 16S rDNA gene fragments from nine H. orientale specimens from Tobago and the mainland to assess their relationship and taxonomy, as well as the tempo and mode of speciation. The results suggest H. orientale from Venezuela and Tobago are monophyletic and the two populations diverged about 3 million years ago. This estimate corresponds with the drier climate and lower sea levels of the Pliocene glaciation periods. We hypothesize that lower sea levels resulted in land-bridge formations connecting the mainland and Tobago, with a corridor of habitat allowing H. orientale to colonize Tobago to the west of Trinidad.

Bovids as indicators of Plio-Pleistocene paleoenvironments in east Africa.

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Kappelman, J; Plummer, T; Bishop, L; Duncan, A; Appleton, S

1997-01-01

Reconstructions of the paleoenvironments of early hominids offer a framework for understanding hominid ecological and behavioral adaptations. Habitat reconstructions typically rely upon various biological or physical habitat indicators, and here we present reconstructions of the Plio-Pleistocene paleohabitats of Koobi Fora and Olduvai Gorge as based on fossil bovids (Artiodactyla: Bovidae). Bovids are the most common faunal element at most Neogene hominid and hominoid fossil localities and have been widely studied. This study addresses the functional morphology of the bovid femur through discriminant function analysis and provides additional support for the observation that certain features of the femur demonstrate clear correlations with the amount of vegetative cover in different modern habitats. The reconstructions for both Koobi Fora and Olduvai Gorge suggest that the full range of environments inhabited by living bovids was present during the Plio-Pleistocene. Koobi Fora appears to have had a somewhat higher percentage of more closed habitats than the relatively more open habitats of Olduvai Gorge. These habitat reconstructions are in broad agreement with other reconstructions based on a purely taxonomic approach to the bovid remains. Grounding our reconstructions of paleoenvironments in studies of functional morphology can help to develop a richer idea of the habitats and resources available to early hominids.

Minimally invasive oesophagectomy more expensive than open despite shorter length of stay.

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Dhamija, Anish; Dhamija, Ankit; Hancock, Jacquelyn; McCloskey, Barbara; Kim, Anthony W; Detterbeck, Frank C; Boffa, Daniel J

2014-05-01

The minimally invasive oesophagectomy (MIO) approach offers a number of advantages over open approaches including reduced discomfort, shorter length of stay and a faster recovery to baseline status. On the other hand, minimally invasive procedures typically are longer and consume greater disposable instrumentation, potentially resulting in a greater overall cost. The objective of this study was to compare costs associated with various oesophagectomy approaches for oesophageal cancer. An institutional Resource Information Management System (RIMS) was queried for cost data relating to hospital expenditures (as opposed to billings or collections). The RIMS was searched for patients undergoing oesophagectomy for oesophageal cancer between 2003 and 2012 via minimally invasive, open transthoracic (OTT) (including Ivor Lewis, modified McKeown or thoracoabdominal) or transhiatal approaches. Patients that were converted from minimally invasive to open, or involved hybrid procedures, were excluded. A total of 160 oesophagectomies were identified, including 61 minimally invasive, 35 open transthoracic and 64 transhiatal. Costs on the day of surgery averaged higher in the MIO group ($12 476 ± 2190) compared with the open groups, OTT ($8202 ± 2512, P < 0.0001) or OTH ($5809 ± 2575, P < 0.0001). The median costs associated with the entire hospitalization also appear to be higher in the MIO group ($25 935) compared with OTT ($24 440) and OTH ($15 248). The average length of stay was lowest in the MIO group (11 ± 9 days) compared with OTT (19 ± 18 days, P = 0.006) and OTH (18 ± 28 days P = 0.07). The operative mortality was similar in the three groups (MIO = 3%, OTT = 9% and OTH = 3%). The operating theatre costs associated with minimally invasive oesophagectomy are significantly higher than OTT or OTH approaches. Unfortunately, a shorter hospital stay after MIO does not consistently offset higher surgical expense, as total hospital costs trend higher in the MIO patients. In

PETROFACIES CHARACTERISTICS OF THE SANDSTONES OF THE UPPER MIOCENELOWER PLIOCENE AGED IN THE ULUMUHSİNE-TATKÖY (KONYA AREA

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A. Müjdat ÖZKAN

2000-03-01

Full Text Available In the study area, Upper Miocene-Lower Pliocene aged Ulumuhsine formation, was formed in a shallow, open lake and river environment. The lithologies of this formation are thin-medium bedded, laminated and fossil rich limestone, thin-thick bedded mudstone, thin-thick bedded marl, thin-thick bedded dolomite with stromatolite interbedded limestone, tuffite, chert bands and coal-rich levels. In addition, it includes conglomerates and sandstones of underwater distrubution channels in lacustrine, and channel and bar sediments in stream environments. Red, gray, rarely green colored sandstones are thin-thick bedded, and in some levels well sorting, in some levels proorly sorting. They present sedimentary structures, as graded, herringbone cross-bedding, symmetric ripple-marks, and laminate. Sandstones are named lithic arenite and lithic graywacke and litharenite, feldspathic litharenite and sublithic arenite. These sandstones are rich rock fragments and quartzs, in addition they contain plagioclase, biotite, muskovite, opaque mineral and epidote. Binding materials of sandstones are mainly calcite cements and clay matrix, and iron oxide cement in little amount. From the mineralogical and textural point of view. As a tectonic environment, the main source of sandstones are recycled orogen (thrust, collision and land uplift and recyded lithic fragments.

Early Pliocene Hiatus in Sand Output by the Colorado River: Evidence From Marine Deposits in the Salton Trough, Southern California

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Dorsey, R. J.; Bykerk-Kauffman, A.

2015-12-01

Early Pliocene deposits in the western Salton Trough preserve a high-fidelity record of sediment dispersal into the marine realm during initiation and early evolution of the Colorado River (CR). Grain-size fractionation, sediment routing, and transport dynamics of the early CR delta are recorded in sediments of the Fish Creek - Vallecito basin, which was located ~100 km south of Yuma along the transform plate boundary at 5 Ma. Early Pliocene delivery of CR sand to the basin took place in two distinct pulses: (1) deposition of sandy turbidites (Wind Caves Mbr of the Latrania Fm) in a restricted submarine canyon at Split Mt Gorge between ~5.3 and 5.1 Ma; and (2) progradation of a thick, widespread, coarsening-up deltaic sequence of marine mudstone, sandstone, and coquinas (Deguynos Fm) between ~4.8 and 4.2 Ma. Estimated flux of CR sediment during Wind Caves deposition was weak (~3-5 Mt/yr) compared to the long-term average (172±64 Mt/yr). The two pulses of CR sand input are separated by the Coyote Clay (CC, ~5.1-4.8 Ma), a regionally correlable, greenish-yellow-weathering marine claystone unit at the base of the Deguynos Fm. CC gradationally overlies Wind Caves turbidites in the area of the paleocanyon. In contrast, in the Coyote Mts 15-23 km to the south and SE, CC rests on coarse-grained locally-derived late Miocene sedimentary rocks, Alverson volcanics, and metamorphic basement rock along a regional unconformity. Identical claystone facies occur in the NW Indio Hills (restores to Yuma at the mouth of the CR at 5 Ma), and Sierra Cucapa in Mexico (~200 km south of Yuma at 5 Ma). Marine localities outside of the Wind Caves paleocanyon experienced slow to negligible sedimentation along a rugged rocky shoreline until abrupt arrival of CR-derived clay. CC accumulated in a sand-starved, pro-delta marine setting (Winker, 1987) over an inferred N-S distance of ~200 km. We therefore reject an alternate hypothesis that CC accumulated on the muddy slope of the prograding CR

Re-visiting the notion of Deep Incarnation in light of 1 Corinthians 15:28 and emergence theory

OpenAIRE

Bentley, Wessel

2016-01-01

Niels Hendrik Gregersen's 'Deep Incarnation' is opening up possibilities for engagement between science and theology. Recent discoveries, like that of Homo naledi, raise questions about how inclusive a Christian doctrine of Incarnation is. Is Jesus only God incarnate for Homo sapien sapiens, or is the incarnation inclusive of preceding hominid species as well? Does the incarnation stretch beyond the hominid line? This chapter engages Gregersen's understanding of Deep Incarnation in light of 1...

Strong spatial structure, Pliocene diversification and cryptic diversity in the Neotropical dry forest spider Sicarius cariri.

Science.gov (United States)

Magalhaes, Ivan L F; Oliveira, Ubirajara; Santos, Fabrício R; Vidigal, Teofânia H D A; Brescovit, Antonio D; Santos, Adalberto J

2014-11-01

The Brazilian Caatinga is part of the seasonally dry tropical forests, a vegetation type disjunctly distributed throughout the Neotropics. It has been suggested that during Pleistocene glacial periods, these dry forests had a continuous distribution, so that these climatic shifts may have acted as important driving forces of the Caatinga biota diversification. To address how these events affected the distribution of a dry forest species, we chose Sicarius cariri, a spider endemic to the Caatinga, as a model. We studied the phylogeography of one mitochondrial and one nuclear gene and reconstructed the paleodistribution of the species using modelling algorithms. We found two allopatric and deeply divergent clades within S. cariri, suggesting that this species as currently recognized might consist of more than one independently evolving lineage. Sicarius cariri populations are highly structured, with low haplotype sharing among localities, high fixation index and isolation by distance. Models of paleodistribution, Bayesian reconstructions and coalescent simulations suggest that this species experienced a reduction in its population size during glacial periods, rather than the expansion expected by previous hypotheses on the paleodistribution of dry forest taxa. In addition to that, major splits of intraspecific lineages of S. cariri took place in the Pliocene. Taken together, these results indicate S. cariri has a complex diversification history dating back to the Tertiary, suggesting the history of dry forest taxa may be significantly older than previously thought. © 2014 John Wiley & Sons Ltd.

"Species" radiations of symbiotic dinoflagellates in the Atlantic and Indo-Pacific since the Miocene-Pliocene transition.

Science.gov (United States)

Lajeunesse, Todd C

2005-03-01

Endosymbiotic dinoflagellates, or "zooxanthellae," are required for the survival of a diverse community of invertebrates that construct and dominate shallow, tropical coral reef ecosystems. Molecular systematics applied to this once understudied symbiont partner, Symbiodinium spp., divide the group into divergent lineages or subgeneric "clades." Within each clade, numerous closely related "types," or species, exhibit distinctive host taxon, geographic, and/or environmental distributions. This diversity is greatest in clade C, which dominates the Indo-Pacific host fauna and shares dominance in the Atlantic-Caribbean with clade B. Two "living" ancestors in this group, C1 and C3, are common to both the Indo-Pacific and Atlantic-Caribbean. With these exceptions, each ocean possesses a diverse clade C assemblage that appears to have independently evolved (adaptively radiated) through host specialization and allopatric differentiation. This phylogeographic evidence suggests that a worldwide selective sweep of C1/C3, or their progenitor, must have occurred before both oceans separated. The probable timing of this event corresponds with the major climactic changes and low CO(2) levels of the late Miocene and/or early Pliocene. Subsequent bursts of diversification have proceeded in each ocean since this transition. An ecoevolutionary expansion to numerous and taxonomically diverse hosts by a select host-generalist symbiont followed by the onset of rapid diversification suggests a radical process through which coral-algal symbioses respond and persist through the vicissitudes of planetary climate change.

Can uncertainties in sea ice albedo reconcile patterns of data-model discord for the Pliocene and 20th/21st centuries?

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Howell, Fergus W.; Haywood, Alan M.; Dolan, Aisling M.; Dowsett, Harry J.; Francis, Jane E; Hill, Daniel J.; Pickering, Steven J.; Pope, James O.; Salzmann, Ulrich; Wade, Bidget S

2014-01-01

General Circulation Model simulations of the mid-Pliocene warm period (mPWP, 3.264 to 3.025 Myr ago) currently underestimate the level of warming that proxy data suggest existed at high latitudes, with discrepancies of up to 11°C for sea surface temperature estimates and 17°C for surface air temperature estimates. Sea ice has a strong influence on high-latitude climates, partly due to the albedo feedback. We present results demonstrating the effects of reductions in minimum sea ice albedo limits in general circulation model simulations of the mPWP. While mean annual surface air temperature increases of up to 6°C are observed in the Arctic, the maximum decrease in model-data discrepancies is just 0.81°C. Mean annual sea surface temperatures increase by up to 2°C, with a maximum model-data discrepancy improvement of 1.31°C. It is also suggested that the simulation of observed 21st century sea ice decline could be influenced by the adjustment of the sea ice albedo parameterization.

Transitional changes in microfossil assemblages in the Japan Sea from the Late Pliocene to Early Pleistocene related to global climatic and local tectonic events

Science.gov (United States)

Itaki, Takuya

2016-12-01

Many micropaleontological studies based on data from on-land sections, oil wells, and deep-sea drilling cores have provided important information about environmental changes in the Japan Sea that are related to the global climate and the local tectonics of the Japanese Islands. Here, major changes in the microfossil assemblages during the Late Pliocene to Early Pleistocene are reviewed. Late Pliocene (3.5-2.7 Ma) surface-water assemblages were characterized mainly by cold-temperate planktonic flora and fauna (nannofossils, diatoms, radiolarians, and planktonic foraminifera), suggesting that nutrient-rich North Pacific surface waters entered the Japan Sea via northern straits. The common occurrence of Pacific-type deep-water radiolarians during this period also suggests that deep water from the North Pacific entered the Japan Sea via the northern straits, indicating a sill depth >500 m. A weak warm-water influence is recognized along the Japanese coast, suggesting a small inflow of warm water via a southern strait. Nannofossil and sublittoral ostracod assemblages record an abrupt cooling event at 2.75 Ma that correlates with the onset of the Northern Hemisphere glaciation. Subsequently, cold intermediate- and deep-water assemblages of ostracods and radiolarians increased in abundance, suggesting active ventilation and the formation of the Japan Sea Proper Water, associated with a strengthened winter monsoon. Pacific-type deep-water radiolarians also disappeared around 2.75 Ma, which is attributed to the intermittent occurrence of deep anoxic environments and limited migration from the North Pacific, resulting from the near-closure or shallowing of the northern strait by a eustatic fall in sea level and tectonic uplift of northeastern Japan. A notable reduction in primary productivity from 2.3 to 1.3 Ma also suggests that the nutrient supply from the North Pacific was restricted by the near-closure of the northern strait. An increase in the abundance of subtropical

Riandando al mio passato

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F. MODIGLIANI

2013-10-01

Full Text Available This article constitutes the slightly modified italian version of a conference held at Trinity College in San Antonio, Texas, the text of which is being published in Lives of the Laureates - Enlarges Edition, MIT Press, Cambridge, Mass. In it, Nobel laureate Franco Modigliani offers readers an informal lesson on modern economic thought through an autobiographical essay touching on his life, career and intellectual development.  JEL Codes: B31 

Petrogenesis of Pliocene Alkaline Volcanic Rocks from Southeastern Styrian Basin, Austria

Science.gov (United States)

Ali, Sh.; Ntaflos, Th.

2009-04-01

Petrogenesis of Pliocene Alkaline Volcanic Rocks from Southeastern Styrian Basin, Austria Sh. Ali and Th. Ntaflos Dept. of Lithospheric Research, University of Vienna, Austria Neogene volcanism in the Alpine Pannonian Transition Zone occurred in a complex geodynamic setting. It can be subdivided into a syn-extentional phase that comprises Middle Miocene dominantly potassic, intermediate to acidic volcanism and a post-extensional phase, which is characterized by eruption of alkaline basaltic magmas during the Pliocene to Quartenary in the Styrian Basin. These alkaline basaltic magmas occur as small eruptive centers dominating the geomorphology of the southeastern part of the Styrian Basin. The eruptive centers along the SE Styrian Basin from North to South are: Oberpullendorf, Pauliberg, Steinberg, Strandenerkogel, Waltrafelsen and Klöch. The suite collected volcanic rocks comprise alkali basalts, basanites and nephelinites. Pauliberg: consists of alkali basalts that exhibit a narrow range of SiO2 (44.66-47.70 wt %) and wide range of MgO (8.52-13.19-wt %), are enriched in TiO2 (3.74-4.18 wt %). They are enriched in incompatible trace elements such as Zr (317-483 ppm), Nb (72.4-138 ppm) and Y (30.7-42 ppm). They have Nb/La ratio of 1.89 (average) and Cen/Ybn=15.22-23.11. Oberpullendorf: it also consists of alkali basalts with higher SiO2 (50.39 wt %) and lower TiO2 (2.80 wt %) if compared with the Pauliberg suite. Incompatible trace elements are lower than in Pauliberg; Zr =217 ppm, Nb=49.8 ppm, Y=23.6 ppm and Nb/La=1.93. The Oberpullendorf alkalibasalts are relative to Pauliberg lavas more depleted in LREE (Cen/Ybn=12.78). Steinberg: it consists of basanites with SiO2=44.49-46.85 wt %, MgO=6.30-9.13-wt %, and TiO2 =2.09-2.26 wt %. They are enriched in incompatible trace elements such as Zr (250-333 ppm), Nb (94-130 ppm), Y (24.7-31.9 ppm) and Nb/La=1.59 (average). The Cen/Ybn ratio varies between 18.17 and 22.83 indicating relative steep REE chondrite normalized

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alle pareti disegnano fragili consonanze, muti spettri della mente ubriaca. Anch'io consumo il mio tempo quando spio i tuoi gesti ignorando lampi cristallini che illuminano facciate misteriose. Sono complice del tuo essere se il tuo silenzio riempie di parole il mio silenzio. “Vivo il tempo degli inganni, preda del grande spirito.

Recidivism of Offenders with Mental Illness Released from Prison to an Intensive Community Treatment Program

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Theurer, Gregory; Lovell, David

2008-01-01

An intensive case management treatment program for mentally ill offenders (MIOs) is outlined, and subsequent recidivism of participants is evaluated. Features of the program and its development are discussed. Sixty-four (64) participants released from state prison between 1998 and 2003 were matched with a group of MIOs released earlier on eight…

Pleistocene Homo sapiens from Middle Awash, Ethiopia.

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White, Tim D; Asfaw, Berhane; DeGusta, David; Gilbert, Henry; Richards, Gary D; Suwa, Gen; Howell, F Clark

2003-06-12

The origin of anatomically modern Homo sapiens and the fate of Neanderthals have been fundamental questions in human evolutionary studies for over a century. A key barrier to the resolution of these questions has been the lack of substantial and accurately dated African hominid fossils from between 100,000 and 300,000 years ago. Here we describe fossilized hominid crania from Herto, Middle Awash, Ethiopia, that fill this gap and provide crucial evidence on the location, timing and contextual circumstances of the emergence of Homo sapiens. Radioisotopically dated to between 160,000 and 154,000 years ago, these new fossils predate classic Neanderthals and lack their derived features. The Herto hominids are morphologically and chronologically intermediate between archaic African fossils and later anatomically modern Late Pleistocene humans. They therefore represent the probable immediate ancestors of anatomically modern humans. Their anatomy and antiquity constitute strong evidence of modern-human emergence in Africa.

Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

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Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.

1977-02-01

The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness.

New paleomagnetic and paleointensity results from late pliocene volcanic sequences from southern Georgia (Caucasus)

Energy Technology Data Exchange (ETDEWEB)

Calvo-Rathert, Manuel; Bogalo, Maria-Felicidad; Carrancho, Angel; Villalain, Juan Jose [Universidad de Burgos, Burgos (Spain). Departamento de Fisica, EPS; Goguichaichvili, Avto [Universidad Nacional Autonoma de Mexico, Morelia (Mexico). Laboratorio de Magnetismo Natural, Instituto de Geofisica; Vegas-Tubia, Nestor [Universidad del Pais Vasco, Bilbao (Spain). Departamento de Geodinamica; Sologashvili, Jemal [Ivane Javakhishvili State University of Tbilisi, Tbilisi (Georgia). Department of Geophysics

2009-07-01

Complete text of publication follows. Paleomagnetic and rock-magnetic experiments were carried out on 21 basaltic lava flows belonging to four different sequences of late Pliocene age from southern Georgia (Caucasus): Dmanisi (11 flows), Diliska (5 flows), Kvemo Orozmani (5 flows), and Zemo Karabulaki (3 flows). Paleomagnetic analysis generally showed the presence of a single component (mainly in the Dmanisi sequence) but also two more or less superimposed components in several other cases. All sites except one clearly displayed a normal-polarity characteristic component. Rock-magnetic experiments included measurement of thermomagnetic curves and hysteresis parameters. Susceptibility-versus-temperature curves measured in argon atmosphere on whole-rock powdered samples yielded low-Ti titanomagnetite as main carrier of remanence, although a lower T{sub C}-component was also observed in several cases. Both reversible and non-reversible k-T curves were measured. A pilot paleointensity study was performed with the Coe (1967) method on two samples of each of those sites considered suitable after interpretation of rock-magnetic and paleomagnetic data from all sites. The pilot study showed that reliable paleointensity results were mainly obtained from sites of the Dmanisi sequence. This thick sequence of basaltic lava flows records the upper end of the normal-polarity Olduvai subchron, a fact confirmed by {sup 40}Ar/{sup 39}Ar dating of the uppermost lava flow and overlying volcanogenic ashes, which yields ages of 1.8 to 1.85 My. A second paleointensity experiment was carried out only on samples belonging to the Dmanisi sequence. Preliminary results show that paleointensities often are low, their values lying between 10 and 20 muT in many cases. For comparison, present day field is 47 muT. The Dmanisi sequence of lava flows directly underlies the Dmanisi paleoanthropologic site, in which the end of the Olduvai subchron is recorded.

Uranium favorability of late Eocene through Pliocene rocks of the South Texas Coastal Plain

International Nuclear Information System (INIS)

Quick, J.V.; Thomas, N.G.; Brogdon, L.D.; Jones, C.A.; Martin, T.S.

1977-02-01

The results of a subsurface uranium favorability study of Tertiary rocks (late Eocene through Pliocene) in the Coastal Plain of South Texas are given. In ascending order, these rock units include the Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand. The Vicksburg Group, Anahuac Formation, and Fleming Formation were not considered because they have unfavorable lithologies. The Yegua Formation, Jackson Group, Frio Clay, Catahoula Tuff, Oakville Sandstone, and Goliad Sand contain sandstones that may be favorable uranium hosts under certain environmental and structural conditions. All except the Yegua are known to contain ore-grade uranium deposits. Yegua and Jackson sandstones are found in strand plain-barrier bar systems that are aligned parallel to depositional and structural strike. These sands grade into shelf muds on the east, and lagoonal sediments updip toward the west. The lagoonal sediments in the Jackson are interrupted by dip-aligned fluvial systems. In both units, favorable areas are found in the lagoonal sands and in sands on the updip side of the strand-plain system. Favorable areas are also found along the margins of fluvial systems in the Jackson. The Frio and Catahoula consist of extensive alluvial-plain deposits. Favorable areas for uranium deposits are found along the margins of the paleo-channels where favorable structural features and numerous optimum sands are present. The Oakville and Goliad Formations consist of extensive continental deposits of fluvial sandstones. In large areas, these fluvial sandstones are multistoried channel sandstones that form very thick sandstone sequences. Favorable areas are found along the margins of the channel sequences. In the Goliad, favorable areas are also found on the updip margin of strand-plain sandstones where there are several sandstones of optimum thickness

Mid-Pliocene shifts in ocean overturning circulation and the onset of Quaternary-style climates

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M. Sarnthein

2009-06-01

Full Text Available A major tipping point of Earth's history occurred during the mid-Pliocene: the onset of major Northern-Hemisphere Glaciation (NHG and of pronounced, Quaternary-style cycles of glacial-to-interglacial climates, that contrast with more uniform climates over most of the preceding Cenozoic and continue until today (Zachos et al., 2001. The severe deterioration of climate occurred in three steps between 3.2 Ma (warm MIS K3 and 2.7 Ma (glacial MIS G6/4 (Lisiecki and Raymo, 2005. Various models (sensu Driscoll and Haug, 1998 and paleoceanographic records (intercalibrated using orbital age control suggest clear linkages between the onset of NHG and the three steps in the final closure of the Central American Seaways (CAS, deduced from rising salinity differences between Caribbean and the East Pacific. Each closing event led to an enhanced North Atlantic meridional overturning circulation and this strengthened the poleward transport of salt and heat (warmings of +2–3°C (Bartoli et al., 2005. Also, the closing resulted in a slight rise in the poleward atmospheric moisture transport to northwestern Eurasia (Lunt et al., 2007, which probably led to an enhanced precipitation and fluvial run-off, lower sea surface salinity (SSS, and an increased sea-ice cover in the Arctic Ocean, hence promoting albedo and the build-up of continental ice sheets. Most important, new evidence shows that the closing of the CAS led to greater steric height of the North Pacific and thus doubled the low-saline Arctic Throughflow from the Bering Strait to the East Greenland Current (EGC. Accordingly, Labrador Sea IODP Site 1307 displays an abrupt but irreversible EGC cooling of 6°C and freshening by ~2 psu from 3.25/3.16–3.00 Ma, right after the first but still reversible attempt of closing the CAS.

Biochemical Characteristics of Organic Matter in a Guano Concretion of Late Miocene or Pliocene Age from Manchester Parish in Jamaica

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Adrian Spence

2013-01-01

Full Text Available The biogeochemical fate of organic matter (OM entering soils is an important issue that must be examined to better understand its roles in nitrogen cycling and as a natural modulator of soil-atmospheric carbon fluxes. Despite these critical roles, there are uncertainties in estimating the contribution of this feedback mechanism due in part to a lack of molecular-level information regarding the origin and labile and refractory inventories of OM in soils. In this study, we used a multi-analytical approach to determine molecular-level information for the occurrence and stabilization of OM in a bird guano concretion of the Late Miocene or Pliocene age in Jamaica. We determined the specific organic structures persisting in the concretion and the possible contribution of fossil organic matter to the OM pool in modern environments. Our results indicate that aliphatic species, presumably of a highly polymethylenic nature [(CH 2 n ], may significantly contribute to the stable soil-C pool. Although not as significant, proteins and carbohydrates were also enriched in the sample, further suggesting that fossil organic matter may contribute to carbon and nitrogen pools in present day soil organic matter.

Aberrant tryptophan transport in cultured fibroblast from patients with Male Idiopathic Osteoporosis: An in vitro study

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Ylva Pernow

2018-06-01

Full Text Available It has been demonstrated, that long-term chronic tryptophan deficiency, results in decreased serotonin synthesis, which may lead to low bone mass and low bone formation. Findings from studies in male patients with idiopathic osteoporosis suggested a decreased transport of tryptophan in erythrocytes of osteoporotic patients, indicating that serotonin system defects may be involved in the etiology of low bone mass. Tryptophan is the precursor of serotonin, and a disturbed transport of tryptophan is implicated in altered serotonin synthesis. However, no study has investigated the tryptophan transport kinetics in MIO patients. The aim of this study is to investigate the kinetic parameters of tryptophan transport in fibroblasts derived from MIO patients compared to age and sex matched controls.Fibroblast cells were cultured from skin biopsies obtained from 14 patients diagnosed with Male Idiopathic Osteoporosis and from 13 healthy age-sex matched controls, without a diagnosis of osteoporosis. Transport of the amino acid tryptophan across the cell membrane was measured by the cluster tray method. The kinetic parameters, maximal transport capacity (Vmax and affinity constant (Km were determined by using the Lineweaver-Burke plot equation.The results of this study have shown a significantly lower mean value for Vmax (p=0.0138 and lower Km mean value (p=0.0009 of tryptophan transport in fibroblasts of MIO patients compared to the control group. A lower Vmax implied a decreased tryptophan transport availability in MIO patients.In conclusion, reduced cellular tryptophan availability in MIO patients might result in reduced brain serotonin synthesis and its endogenous levels in peripheral tissues, and this may contribute to low bone mass/formation. The findings of the present study could contribute to the etiology of idiopathic osteoporosis and for the development of novel approaches for diagnosis, treatment and management strategies of MIO. Keywords: Male

Propellant Containers and Expulsion Charges for M483A1 and M509 Projectiles.

Science.gov (United States)

1986-08-01

program. This malfunction occurred when a 58 g charge of MIO propellant misfired at -65*F. Phase II The celcon/acrylic bags had a history of a high...polyethylene loaded bags, making a total of 38 bags, each type containing 51 g of MIO propellant, were submitted to EMD, Chemistry Brioch for the following

Facial orientation and facial shape in extant great apes: a geometric morphometric analysis of covariation.

Science.gov (United States)

Neaux, Dimitri; Guy, Franck; Gilissen, Emmanuel; Coudyzer, Walter; Vignaud, Patrick; Ducrocq, Stéphane

2013-01-01

The organization of the bony face is complex, its morphology being influenced in part by the rest of the cranium. Characterizing the facial morphological variation and craniofacial covariation patterns in extant hominids is fundamental to the understanding of their evolutionary history. Numerous studies on hominid facial shape have proposed hypotheses concerning the relationship between the anterior facial shape, facial block orientation and basicranial flexion. In this study we test these hypotheses in a sample of adult specimens belonging to three extant hominid genera (Homo, Pan and Gorilla). Intraspecific variation and covariation patterns are analyzed using geometric morphometric methods and multivariate statistics, such as partial least squared on three-dimensional landmarks coordinates. Our results indicate significant intraspecific covariation between facial shape, facial block orientation and basicranial flexion. Hominids share similar characteristics in the relationship between anterior facial shape and facial block orientation. Modern humans exhibit a specific pattern in the covariation between anterior facial shape and basicranial flexion. This peculiar feature underscores the role of modern humans' highly-flexed basicranium in the overall integration of the cranium. Furthermore, our results are consistent with the hypothesis of a relationship between the reduction of the value of the cranial base angle and a downward rotation of the facial block in modern humans, and to a lesser extent in chimpanzees.

Security and Privacy in the Medical Internet of Things: A Review

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Wencheng Sun

2018-01-01

Full Text Available Medical Internet of Things, also well known as MIoT, is playing a more and more important role in improving the health, safety, and care of billions of people after its showing up. Instead of going to the hospital for help, patients’ health-related parameters can be monitored remotely, continuously, and in real time, then processed, and transferred to medical data center, such as cloud storage, which greatly increases the efficiency, convenience, and cost performance of healthcare. The amount of data handled by MIoT devices grows exponentially, which means higher exposure of sensitive data. The security and privacy of the data collected from MIoT devices, either during their transmission to a cloud or while stored in a cloud, are major unsolved concerns. This paper focuses on the security and privacy requirements related to data flow in MIoT. In addition, we make in-depth study on the existing solutions to security and privacy issues, together with the open challenges and research issues for future work.

Antarctic climate and ice-sheet configuration during the early Pliocene interglacial at 4.23 Ma

Science.gov (United States)

Golledge, Nicholas R.; Thomas, Zoë A.; Levy, Richard H.; Gasson, Edward G. W.; Naish, Timothy R.; McKay, Robert M.; Kowalewski, Douglas E.; Fogwill, Christopher J.

2017-07-01

The geometry of Antarctic ice sheets during warm periods of the geological past is difficult to determine from geological evidence, but is important to know because such reconstructions enable a more complete understanding of how the ice-sheet system responds to changes in climate. Here we investigate how Antarctica evolved under orbital and greenhouse gas conditions representative of an interglacial in the early Pliocene at 4.23 Ma, when Southern Hemisphere insolation reached a maximum. Using offline-coupled climate and ice-sheet models, together with a new synthesis of high-latitude palaeoenvironmental proxy data to define a likely climate envelope, we simulate a range of ice-sheet geometries and calculate their likely contribution to sea level. In addition, we use these simulations to investigate the processes by which the West and East Antarctic ice sheets respond to environmental forcings and the timescales over which these behaviours manifest. We conclude that the Antarctic ice sheet contributed 8.6 ± 2.8 m to global sea level at this time, under an atmospheric CO2 concentration identical to present (400 ppm). Warmer-than-present ocean temperatures led to the collapse of West Antarctica over centuries, whereas higher air temperatures initiated surface melting in parts of East Antarctica that over one to two millennia led to lowering of the ice-sheet surface, flotation of grounded margins in some areas, and retreat of the ice sheet into the Wilkes Subglacial Basin. The results show that regional variations in climate, ice-sheet geometry, and topography produce long-term sea-level contributions that are non-linear with respect to the applied forcings, and which under certain conditions exhibit threshold behaviour associated with behavioural tipping points.

Significance of some previously unrecognized apomorphies in the nasal region of Homo neanderthalensis.

OpenAIRE

Schwartz, J H; Tattersall, I

1996-01-01

For many years, the Neanderthals have been recognized as a distinctive extinct hominid group that occupied Europe and western Asia between about 200,000 and 30,000 years ago. It is still debated, however, whether these hominids belong in their own species, Homo neanderthalensis, or represent an extinct variant of Homo sapiens. Our ongoing studies indicate that the Neanderthals differ from modern humans in their skeletal anatomy in more ways than have been recognized up to now. The purpose of ...

uno sguardo sul colonialismo italiano: gli scritti di erminia dell'oro

African Journals Online (AJOL)

User

un'esperienza vissuta accompagnando il mio nipotino al museo di. Storia Naturale di Milano. Da allora ho continuato a scrivere per i ragazzi l'ultimo mio libro s'intitola Il gatto rapito, edito dal Battello a. Vapore”. Nonostante abbia lasciato l'Eritrea a vent'anni e da quel momento abbia sempre vissuto a Milano, nel corso della ...

Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary.

Science.gov (United States)

Krause, Johannes; Unger, Tina; Noçon, Aline; Malaspinas, Anna-Sapfo; Kolokotronis, Sergios-Orestis; Stiller, Mathias; Soibelzon, Leopoldo; Spriggs, Helen; Dear, Paul H; Briggs, Adrian W; Bray, Sarah C E; O'Brien, Stephen J; Rabeder, Gernot; Matheus, Paul; Cooper, Alan; Slatkin, Montgomery; Pääbo, Svante; Hofreiter, Michael

2008-07-28

Despite being one of the most studied families within the Carnivora, the phylogenetic relationships among the members of the bear family (Ursidae) have long remained unclear. Widely divergent topologies have been suggested based on various data sets and methods. We present a fully resolved phylogeny for ursids based on ten complete mitochondrial genome sequences from all eight living and two recently extinct bear species, the European cave bear (Ursus spelaeus) and the American giant short-faced bear (Arctodus simus). The mitogenomic data yield a well-resolved topology for ursids, with the sloth bear at the basal position within the genus Ursus. The sun bear is the sister taxon to both the American and Asian black bears, and this clade is the sister clade of cave bear, brown bear and polar bear confirming a recent study on bear mitochondrial genomes. Sequences from extinct bears represent the third and fourth Pleistocene species for which complete mitochondrial genomes have been sequenced. Moreover, the cave bear specimen demonstrates that mitogenomic studies can be applied to Pleistocene fossils that have not been preserved in permafrost, and therefore have a broad application within ancient DNA research. Molecular dating of the mtDNA divergence times suggests a rapid radiation of bears in both the Old and New Worlds around 5 million years ago, at the Miocene-Pliocene boundary. This coincides with major global changes, such as the Messinian crisis and the first opening of the Bering Strait, and suggests a global influence of such events on species radiations.

Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary

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Rabeder Gernot

2008-07-01

Full Text Available Abstract Background Despite being one of the most studied families within the Carnivora, the phylogenetic relationships among the members of the bear family (Ursidae have long remained unclear. Widely divergent topologies have been suggested based on various data sets and methods. Results We present a fully resolved phylogeny for ursids based on ten complete mitochondrial genome sequences from all eight living and two recently extinct bear species, the European cave bear (Ursus spelaeus and the American giant short-faced bear (Arctodus simus. The mitogenomic data yield a well-resolved topology for ursids, with the sloth bear at the basal position within the genus Ursus. The sun bear is the sister taxon to both the American and Asian black bears, and this clade is the sister clade of cave bear, brown bear and polar bear confirming a recent study on bear mitochondrial genomes. Conclusion Sequences from extinct bears represent the third and fourth Pleistocene species for which complete mitochondrial genomes have been sequenced. Moreover, the cave bear specimen demonstrates that mitogenomic studies can be applied to Pleistocene fossils that have not been preserved in permafrost, and therefore have a broad application within ancient DNA research. Molecular dating of the mtDNA divergence times suggests a rapid radiation of bears in both the Old and New Worlds around 5 million years ago, at the Miocene-Pliocene boundary. This coincides with major global changes, such as the Messinian crisis and the first opening of the Bering Strait, and suggests a global influence of such events on species radiations.

Unmelted meteoritic debris in the Late Pliocene iridium anomaly - Evidence for the ocean impact of a nonchondritic asteroid

Science.gov (United States)

Kyte, F. T.; Brownlee, D. E.

1985-01-01

Ir-bearing particles have been recovered from two piston cores in the Antarctic Basin in the southeastern Pacific. In core E13-3, the particles closely correspond to the Late Pliocene Ir anomaly and have a fluence of about 100 mg/cm sq. In core E13-4, 120 km to the southwest, the particle fluence is about 4 mg/cm sq. Particles with diameters from 0.5 to 4 mm contain at least 35 percent of the Ir in this horizon. Three types of particles have been identified: (1) vesicular, (2) basaltic, and (3) metal. The vesicular particles appear to be shock-melted debris derived from the oceanic impact of a howarditic asteroid containing a minor metal component. These particles have recrystallized from a melt and impact into the ocean has resulted in the incorporation of Na, K, Cl, and radiogenic Sr from the ocean water target. The basaltic clasts appear to be unmelted fragments of the original asteroid which may have separated from the main body prior to impact. Combined vesicular and basaltic particles are believed to have formed by collisions in the debris cloud. Estimates of the diameter of the projectile range from 100 to 500 m. By many orders of magnitude, this is the most massive achondrite sampled by a single meteorite fall.

First report of bats (Mammalia: Chiroptera from the Gray Fossil Site (late Miocene or early Pliocene, Tennessee, USA

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Nicholas J. Czaplewski

2017-04-01

Full Text Available Thousands of vertebrate fossils have been recovered from the Gray Fossil Site, Tennessee, dating to the Miocene-Pliocene boundary. Among these are but eight specimens of bats representing two different taxa referable to the family Vespertilionidae. Comparison of the fossils with Neogene and Quaternary bats reveals that seven of the eight specimens pertain to a species of Eptesicus that cannot be distinguished from recent North American Eptesicus fuscus. The remaining specimen, a horizontal ramus with m3, is from a smaller vespertilionid bat that cannot confidently be assigned to a genus. Although many vespertilionid genera can be excluded through comparisons, and many extinct named taxa cannot be compared due to nonequivalence of preserved skeletal elements, the second taxon shows morphological similarities to small-bodied taxa with three lower premolar alveoli, three distinct m3 talonid cusps, and m3 postcristid showing the myotodont condition. It resembles especially Nycticeius humeralis and small species of Eptesicus. Eptesicus cf. E. fuscus potentially inhabited eastern North America continuously since the late Hemphillian land mammal age, when other evidence from the Gray Fossil Site indicates the presence in the southern Appalachian Mountains of a warm, subtropical, oak-hickory-conifer forest having autochthonous North American as well as allochthonous biogeographical ties to eastern Asia and tropical-subtropical Middle America.

Orbital time scale records of Asian eolian dust from the Sea of Japan since the early Pliocene

Science.gov (United States)

Zhang, Wenfang; De Vleeschouwer, David; Shen, Ji; Zhang, Zeke; Zeng, Lin

2018-05-01

A high-resolution potassium content record of sediments from Integrated Ocean Drilling Program (IODP) Site U1422 drilled in the northern Sea of Japan was employed to yield an astronomical timescale for this ∼205 m thick sedimentary archive. The K content was quantified using the natural gamma radiation (NGR) data routinely measured on DV JOIDES Resolution. The U1422 K (wt.%) series shows an increasing trend with time, which parallels the growth of North Hemisphere ice sheets since ∼4 Ma, as revealed by the global benthic foraminifer's oxygen isotope stack (LR04). We propose that K content variations reflect changes in the relative contributions of Asian eolian dust and volcanic weathering products, in response to changes in global ice volume. Using the shipboard age model, constrained by palaeomagnetism and nanofossils datums, we tuned the U1422 K content variations to the LR04 stack. Our tuned age model for site U1422 goes back to 3.9 Ma. The studied record indicates that Asian dust generation is enhanced during periods of global cooling. The synchronous variations between the U1422 K record and the LR04 stack also suggest that global cooling played a dominant role in promoting the central Asian aridification since ∼3.9 Ma, while the uplift of Tibetan Plateau plays a secondary role, considering many disagreements still exists between the timing and amplitude of the Qinghai-Tibetan uplift and the evolution of central Asian aridity since the early Pliocene.

The beginnings of human palaeontology: prehistory, craniometry and the 'fossil human races'.

Science.gov (United States)

Goodrum, Matthew R

2016-09-01

Since the nineteenth century, hominid palaeontology has offered critical information about prehistoric humans and evidence for human evolution. Human fossils discovered at a time when there was growing agreement that humans existed during the Ice Age became especially significant but also controversial. This paper argues that the techniques used to study human fossils from the 1850s to the 1870s and the way that these specimens were interpreted owed much to the anthropological examination of Stone, Bronze, and Iron Age skeletons retrieved by archaeologists from prehistoric tombs throughout Europe. What emerged was the idea that a succession of distinct human races, which were identified using techniques such as craniometry, had occupied and migrated into Europe beginning in the Ice Age and continuing into the historic period. This marks a phase in the history of human palaeontology that gradually gave way to a science of palaeoanthropology that viewed hominid fossils more from the perspective of evolutionary theory and hominid phylogeny.

Tertiary block rotations in the Fars Arc (Zagros, Iran)

Science.gov (United States)

Aubourg, C.; Smith, B.; Bakhtari, H. R.; Guya, N.; Eshraghi, A.

2008-05-01

The Fars arc accommodates the oblique convergence between the Arabic plate and the Iran block. Many geological observations suggest block rotations from regional to local scales. We present palaeomagnetic investigations in the Fars arc and its eastern termination, the Zagros-Makran syntaxis. Sixty-four sites have been sampled covering the Palaeocene Pabdeh Fm. to Mio-Pliocene Agha-Jhari Fm., the latest being the most sampled formation. We document pre-tilting components in all formations. However, coarse fractions of Agha-Jhari clastics formation retain a post-tilting remagnetization. As a whole, block rotations rarely exceed 20°. In the western Fars arc, clockwise and counter-clockwise rotations of small amplitudes are consistent with the torsions observed near the strike slip Kazerun and Mangarak faults. In the Zagros Makran syntaxis, counter-clockwise and clockwise rotations are observed, respectively, in the western and eastern part. This pattern is consistent with an amplification of the shape of the syntaxis. Between Zagros and Makran, palaeomagnetic data support that the present-day arcuate shape of the arc is secondary. We assume that most of the block rotations took place during the Plio-Pleistocene, during a blocking stage of the Zagros-Makran syntaxis. We emphasize the role of Oman Peninsula which plays as an indenter for the propagation of the Fars thrust belt.

Foramen magnum position in bipedal mammals.

Science.gov (United States)

Russo, Gabrielle A; Kirk, E Christopher

2013-11-01

The anterior position of the human foramen magnum is often explained as an adaptation for maintaining balance of the head atop the cervical vertebral column during bipedalism and the assumption of orthograde trunk postures. Accordingly, the relative placement of the foramen magnum on the basicranium has been used to infer bipedal locomotion and hominin status for a number of Mio-Pliocene fossil taxa. Nonetheless, previous studies have struggled to validate the functional link between foramen magnum position and bipedal locomotion. Here, we test the hypothesis that an anteriorly positioned foramen magnum is related to bipedalism through a comparison of basicranial anatomy between bipeds and quadrupeds from three mammalian clades: marsupials, rodents and primates. Additionally, we examine whether strepsirrhine primates that habitually assume orthograde trunk postures exhibit more anteriorly positioned foramina magna compared with non-orthograde strepsirrhines. Our comparative data reveal that bipedal marsupials and rodents have foramina magna that are more anteriorly located than those of quadrupedal close relatives. The foramen magnum is also situated more anteriorly in orthograde strepsirrhines than in pronograde or antipronograde strepsirrhines. Among the primates sampled, humans exhibit the most anteriorly positioned foramina magna. The results of this analysis support the utility of foramen magnum position as an indicator of bipedal locomotion in fossil hominins. Copyright © 2013 Elsevier Ltd. All rights reserved.

Molecular data and ecological niche modelling reveal a highly dynamic evolutionary history of the East Asian Tertiary relict Cercidiphyllum (Cercidiphyllaceae).

Science.gov (United States)

Qi, Xin-Shuai; Chen, Chen; Comes, Hans Peter; Sakaguchi, Shota; Liu, Yi-Hui; Tanaka, Nobuyuki; Sakio, Hitoshi; Qiu, Ying-Xiong

2012-10-01

East Asia's temperate deciduous forests served as sanctuary for Tertiary relict trees, but their ages and response to past climate change remain largely unknown. To address this issue, we elucidated the evolutionary and population demographic history of Cercdiphyllum, comprising species in China/Japan (Cercdiphyllum japonicum) and central Japan (Cercdiphyllum magnificum). Fifty-three populations were genotyped using chloroplast and ribosomal DNA sequences and microsatellite loci to assess molecular structure and diversity in relation to past (Last Glacial Maximum) and present distributions based on ecological niche modelling. Late Tertiary climate cooling was reflected in a relatively recent speciation event, dated at the Mio-/Pliocene boundary. During glacials, the warm-temperate C. japonicum experienced massive habitat losses in some areas (north-central China/north Japan) but increases in others (southwest/-east China, East China Sea landbridge, south Japan). In China, the Sichuan Basin and/or the middle-Yangtze were source areas of postglacial northward recolonization; in Japan, this may have been facilitated through introgressive hybridization with the cool-temperate C. magnificum. Our findings challenge the notion of relative evolutionary and demographic stability of Tertiary relict trees, and may serve as a guideline for assessing the impact of Neogene climate change on the evolution and distribution of East Asian temperate plants. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

Uso de teste de químio-sensibilidade para escolha da quimioterapia adjuvante no câncer gástrico avançado

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Wilson Shinjiro Matsuzaki

Full Text Available OBJETIVO: Introduzir e familiarizar em nosso meio o uso do teste de químio-sensibilidade MTT avaliando a ação de agentes quimioterápicos sobre células tumorais de 30 doentes com câncer gástrico avançado. Correlacionar os resultados do teste MTT com os aspectos clínicos, anátomo-patológicos e estádio utlizando a mesma metodologia do estudo realizado em pacientes japoneses na Universidade de Keio, Japão. MÉTODO: Foi realizado o teste MTT em tumores de 30 pacientes com diagnóstico de adenocarcinoma gástrico, submetidos ao tratamento cirúrgico no Departamento de Cirurgia da Faculdade de Ciências Médicas da Santa Casa de São Paulo. Foram estudados in vitro os seguintes agentes quimioterápicos: mitomicina C, doxorrubicina, cisplatina e 5-fluorouracil. RESULTADOS: Os índices de atividade sobre células tumorais foram: 16,6% para a mitomicina C, 10,0% para a doxorrubicina, 6,6% para a cisplatina e 6,6% para o 5-fluorouracil. Os resultados do teste MTT não tiveram correlação com a idade, sexo, aspectos microscópicos e estádio (p0,05. CONCLUSÕES: A ação dos agentes quimioterápicos estudados sobre células tumorais do câncer gástrico foi baixa. Os resultados da ação dos quimioterápicos in vitro não apresentou correlação estatística com a idade, sexo, aspectos microscópicos e estádio destes doentes. Utilizando a mesma metodologia, tanto em nosso meio como em pacientes japoneses, a quimio-sensibilidade se mostrou baixa em ambos os estudos, podendo-se deduzir também que os resultados da químiosensibilidade independe da etnia. Com o surgimento de novos agentes quimioterápicos, a expectativa é grande para melhores resultados na prática clínica. Com a utilização e difusão do teste MTT em nosso meio, poder-se-á criar protocolos e estudos multicêntricos para selecionar os quimioterápicos a serem utlizados.

Early Pliocene anuran fossils from Kanapoi, Kenya, and the first fossil record for the African burrowing frog Hemisus (Neobatrachia: Hemisotidae).

Science.gov (United States)

Delfino, Massimo

2017-07-13

Isolated amphibian bones from the early Pliocene of Kanapoi (West Turkana, Kenya) help to improve the scarce fossil record of the late Neogene and Quaternary amphibians from East Africa. All currently available 579 bones are referable exclusively to the Anura (frogs and toads). More than half of the remains (366) are identified as Hemisus cf. Hemisus marmoratus, an extant species that still inhabits Kenya, but apparently not the northwest of the country and the Turkana area in particular. The rest of the remains are identified simply as Anura indet. because of poor preservation or non congruence with the relatively few African extant taxa whose osteology is known in detail. The Hemisus material represents the first fossil record for Hemisotidae, an endemic African family of peculiar, head-first burrowing frogs, whose sister taxon relationships indicate a divergence from brevicipitids in the Late Cretaceous or early Paleocene. The ecological requirements of extant H. marmoratus suggest that the Kanapoi area surrounding the fluvial and deltaic settings, from where the fossil remains of vertebrates were buried, was likely a grassland or relatively dry, open low tree-shrub savanna. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dansk turisme savner en samlet plan

DEFF Research Database (Denmark)

Lyck, Lise; Jensen, Sune K.

2013-01-01

Turisterhvervet er internationalt set et væksterhverv. I 1950 holdt 25 mio. turister ferie i udlandet, i 2012 1.035 mio., og i 2030 forventes 1,8 mia. at rejse udenlands. Det var derfor rigtigt set af regeringen at nedsætte et vækstteam på området, for dansk turisme har potentialet til at skabe v...

Les leishmanioses cutanées à Leishmania major et à Leishmania tropica au Maroc: aspects épidémio-cliniques comparatifs de 268 cas

Science.gov (United States)

Chiheb, Soumia; Slaoui, Widad; Mouttaqui, Tarik; Riyad, Meriem; Benchikhi, Hakima

2014-01-01

Introduction Depuis 1995, le Maroc a connu une réactivation des foyers de leishmanioses cutanées (LC) à L. major et une nouvelle répartition géographique des foyers à L. tropica. Le but de cette étude est de comparer les aspects épidémio-cliniques associés aux LC potentiellement dûes à L. major et à L. tropica. Méthodes Une étude rétrospective a colligé 268 cas de LC au service de dermatologie du CHU Ibn Rochd de Casablanca entre Janvier 1995 et Septembre 2010. Les données étaient analysées par Epi info version 3.5.1. Le test X2 était appliqué (Différence significative = p< 0,05). Résultats Deux cent soixante-huit cas de LC ont été colligés, dont 160 femmes et 108 hommes. Ils ont été répartis en 123 patients originaires des foyers à L.major et 145 patients originaires des foyers à L. tropica. L'aspect ulcéronodulaire, ulcérovégétant ou végétant était retrouvé dans 58 cas (47,2%) des cas de LC à L. major versus 24 cas (16,7%) dans la L.C à L. tropica. L'aspect papulonodulaire était retrouvé dans 84 cas (58%) de LC à L. tropica contre 41 cas (33,3%) de LC à L. major. Conclusion Dans la LC à L. major, l'atteinte des membres et les aspects cliniques végétant ou ulcéro-végétant restent toujours prédominants. Dans la L.C à L. tropica, l'atteinte papulonodulaire unique du visage reste prédominante mais des formes ulcéronodulaires, végétantes ou ulcérovégétantes existent également dans les foyers récents à L. tropica, prêtant à confusion cliniquement avec des LC à L. major. PMID:25810796

A Comprehensive Exploration of Java Man: Bio-Cultural Evolution from Homo erectus to Homo sapiens

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Samuel J Haryono

2017-02-01

An overlap of time period between Homo erectus and Homo sapiens has not been confirmed. In the history of man, there have been two missing links: one between man and ape, and one between progressive Homo erectus and archaic Homo sapiens.  Specimen dating on Java Man has been discrepant among research groups, and the use of molecular biology in ancient specimens has been a novelty. This study intends to use fossilised specimens, to harvest DNA to be sequenced for ribosomal DNA analysis for comparative phylogeny among ancient and modern man and other hominids. Dental calculus will be analysed to identify starch, carbohydrate, and protein to illustrate paleo dietary pattern. Soil samples will be examined for pollen and phytoliths to elaborate on ancient ecosystem. Blood samples will be procured from indigenous people along the riverflow region of Bengawan Solo to analyse modern human DNA. We hope that we may reconstruct the evolution pathway, construct the phylogenetic tree between ancient and modern hominids, and discover the uniqueness of Homo sapiens sapiens. Keywords: Java Man, Ribosomal DNA, Hominid Phylogenetic,

Great apes prefer cooked food.

Science.gov (United States)

Wobber, Victoria; Hare, Brian; Wrangham, Richard

2008-08-01

The cooking hypothesis proposes that a diet of cooked food was responsible for diverse morphological and behavioral changes in human evolution. However, it does not predict whether a preference for cooked food evolved before or after the control of fire. This question is important because the greater the preference shown by a raw-food-eating hominid for the properties present in cooked food, the more easily cooking should have been adopted following the control of fire. Here we use great apes to model food preferences by Paleolithic hominids. We conducted preference tests with various plant and animal foods to determine whether great apes prefer food items raw or cooked. We found that several populations of captive apes tended to prefer their food cooked, though with important exceptions. These results suggest that Paleolithic hominids would likewise have spontaneously preferred cooked food to raw, exapting a pre-existing preference for high-quality, easily chewed foods onto these cooked items. The results, therefore, challenge the hypothesis that the control of fire preceded cooking by a significant period.

FOSSIL VERTEBRATES (MAMMALIA AND REPTILIA FROM CAPO MANNU (LATE PLIOCENE, WESTERN SARDINIA, ITALY, WITH DESCRIPTION OF A NEWTESTUDO (CHELONII, TESTUDINIDAE SPECIES

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LAURA ABBAZZI

2008-03-01

Full Text Available In the North-West Sinis Peninsula (Western Sardinia a stratigraphic sequence, the Capo Mannu Fm., that evolves from marine-littoral to continental-dunar, is present. A vertebrate fauna is reported within the middle part of this coastal dune complex. These new remains, here referred to as the Capo Mannu D4 Local Fauna, are slightly younger in the sedimentary succession than the Local Fauna known in the literature as Mandriola and here re-named the Capo Mannu D1 Local Fauna.Vertebrates from Capo Mannu D4 include reptiles (Chelonii and mammals (Bovidae and Suidae. The tortoise fossils show peculiarities of shape that require the naming of a new species. The suid material includes a fragmentary palate and a partial mandible, referable to the endemic species Sus sondaari. Bovids are well represented in the assemblage, although quite fragmentary. They have been identified as belonging to at least two forms. One of these is comparable in morphology to Nesogoral, one of the most characteristic taxa of the Late Pliocene-Early Pleistocene Sardinian endemic fauna (the so called "Nesogoral complex". On the whole, the Capo Mannu D4 assemblages open a new window on the Plio-Pleistocene terrestrial faunas of the Sardinian Island. 

The Pliocene Horcón Formation, Central Chile: a case study of earthquake-induced landslide susceptibility

Science.gov (United States)

Valdivia, D.; Elgueta, S.; Hodgkin, A.; Marquardt, C.; del Valle, F.; Yáñez Morroni, G.

2017-12-01

Stability slope analysis is typically focused on modeling using cohesion and friction angle parameters but in earthquake-induced landslides, susceptibility is correlated more to lithological and stratigraphic parameters. In sedimentary deposits whose cohesion and diagenesis are very low, the risk of landslides increases. The Horcón Formation, which crops out continuously along cliffs in Central Chile between 32.5° and 33°S, is a Miocene-Pliocene well preserved, horizontally stratified unit composed of marine strata which overlies Paleozoic-Mesozoic igneous basement. During the Quaternary, the sequence was tectonically uplifted 80 meters and covered by unconsolidated eolian deposits. Given that Seismotectonic and Barrier-Asperity models suggest the occurrence of a forthcoming megathrust earthquake in a segment which includes this area, the Horcón Formation constitutes a good case study to characterize the susceptibility of this type of sediment for mass movements triggered by earthquakes. Field mapping, stratigraphic and sedimentological studies, including petrographic analyses to determine lithological composition and paragenesis of diagenetic events, have been carried out along with limited gravimetric profiling and CPTU drill tests. High resolution digital elevation modeling has also been applied. This work has led to the recognition of a shallow marine lithofacies association composed of weakly lithified fossiliferous and bioturbated medium to fine grained litharenite, mudstone, and fine conglomerate. The low grade of diagenesis in the sedimentary deposits was in response to a short period of burial and a subsequent accelerated uplift evidenced along the coast of Chile during the Quaternary. We have generated a predictive model of landslide susceptibility for the Horcón Formation and for the overlying Quaternary eolian deposits incorporating variables such as composition and diagenesis of lithofacies, slope, structures, weathering and landcover. The model

Antarctic climate and ice-sheet configuration during the early Pliocene interglacial at 4.23 Ma

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N. R. Golledge

2017-07-01

Full Text Available The geometry of Antarctic ice sheets during warm periods of the geological past is difficult to determine from geological evidence, but is important to know because such reconstructions enable a more complete understanding of how the ice-sheet system responds to changes in climate. Here we investigate how Antarctica evolved under orbital and greenhouse gas conditions representative of an interglacial in the early Pliocene at 4.23 Ma, when Southern Hemisphere insolation reached a maximum. Using offline-coupled climate and ice-sheet models, together with a new synthesis of high-latitude palaeoenvironmental proxy data to define a likely climate envelope, we simulate a range of ice-sheet geometries and calculate their likely contribution to sea level. In addition, we use these simulations to investigate the processes by which the West and East Antarctic ice sheets respond to environmental forcings and the timescales over which these behaviours manifest. We conclude that the Antarctic ice sheet contributed 8.6 ± 2.8 m to global sea level at this time, under an atmospheric CO2 concentration identical to present (400 ppm. Warmer-than-present ocean temperatures led to the collapse of West Antarctica over centuries, whereas higher air temperatures initiated surface melting in parts of East Antarctica that over one to two millennia led to lowering of the ice-sheet surface, flotation of grounded margins in some areas, and retreat of the ice sheet into the Wilkes Subglacial Basin. The results show that regional variations in climate, ice-sheet geometry, and topography produce long-term sea-level contributions that are non-linear with respect to the applied forcings, and which under certain conditions exhibit threshold behaviour associated with behavioural tipping points.

Ultraviolet detecting properties of amorphous MgInO thin film phototransistors

International Nuclear Information System (INIS)

Lu, Huiling; Bi, Xiaobin; Zhang, Shengdong; Zhou, Hang

2015-01-01

The ultraviolet (UV) detecting properties of Mg doped In 2 O 3 (MgInO or MIO) bottom gate thin film transistors (TFTs) were investigated. The optical measurements show that the introduction of Mg dopants effectively widens the optical band gap of In 2 O 3 . The cutoff wavelength of MIO films is pushed to deep UV as Mg content increases. Fabricated MIO TFTs with high Mg content demonstrate appraisable UV detecting properties with a dark current of 10 −14 A, a UV to visible rejection ratio of 10 3 , a responsivity of 3.2 A/W (300 nm) and a cutoff wavelength of 320 nm, which can be put to good use in deep UV detection. The dynamic photo-response measurement shows that the persistent photo-conductivity (PPC) effect can be alleviated by imposing a transient positive gate pulse. (paper)

Re-visiting the notion of Deep Incarnation in light of 1 Corinthians 15:28 and emergence theory

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Wessel Bentley

2016-08-01

Full Text Available Niels Hendrik Gregersen’s ‘Deep Incarnation’ is opening up possibilities for engagementbetween science and theology. Recent discoveries, like that of Homo naledi, raise questions abouthow inclusive a Christian doctrine of Incarnation is. Is Jesus only God incarnate for Homo sapiensapiens, or is the incarnation inclusive of preceding hominid species as well? Does the incarnationstretch beyond the hominid line? This chapter engages Gregersen’s understanding of DeepIncarnation in light of 1 Corinthians 15:28 and emergence theory. It proposes that there is a directcorrelation between worldview and how we believe in the inclusive nature of divine incarnation.

A reappraisal of the stratigraphy and chronology of Early Pliocene palaeontological sites from Lanzarote Island containing fossil terrestrial animals

Science.gov (United States)

Lomoschitz, Alejandro; Sánchez Marco, Antonio; Huertas, María José; Betancort, Juan F.; Isern, Arnau; Sanz, Elena; Meco, Joaquín

2016-11-01

The Famara massif, in the north of Lanzarote Island, constitutes the remains of a former island inhabited by the oldest known vertebrate fauna of the Canary archipelago off the coast of Africa. In this study, new ages are offered for the underlying and overlying basaltic lava flows of two paleontological sites. The island's three major palaeontological sites, which contain remains of this ancient fauna (Valle Grande, Valle Chico and Fuente de Gusa), are intercorrelated according to their lithologies, sedimentology, palaeontological content and geochronology. The new K/Ar age interval for the fossiliferous sedimentary deposits ranges between 4.3 ± 0.7 and 3.78 ± 0.71 Ma, within the Early Pliocene, and shows that the first known terrestrial animals in Lanzarote were present on the island for about 500 ka. The principal component of the deposits is a bioclastic calcarenite of aeolian origin (sand sheet deposits), which is present in all three sites and constitutes 65% of the beds. The remaining 35% is of fluvial-aeolian origin (mainly stream deposits). All the beds contain the same fossils (insect egg pods, land snails, avian eggshells and tortoise eggshells). The local palaeogeography and the formation of the deposits were conditioned by a flat plain, larger than 16 km2, over which aeolian sands moved freely with a prevailing NNE-WSW wind direction. In agreement with previous investigations, the palaeoclimate in this interval (ca. 4.3 to 3.8 Ma) must have been mainly dry with some rainy episodes.

Phylogeography of Australia's king brown snake (Pseudechis australis) reveals Pliocene divergence and Pleistocene dispersal of a top predator

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Kuch, Ulrich; Keogh, J. Scott; Weigel, John; Smith, Laurie A.; Mebs, Dietrich

2005-03-01

King brown snakes or mulga snakes (Pseudechis australis) are the largest and among the most dangerous and wide-ranging venomous snakes in Australia and New Guinea. They occur in diverse habitats, are important predators, and exhibit considerable morphological variation. We infer the relationships and historical biogeography of P. australis based on phylogenetic analysis of 1,249 base pairs from the mitochondrial cytochrome b, NADH dehydrogenase subunit 4 and three adjacent tRNA genes using Bayesian, maximum-likelihood, and maximum-parsimony methods. All methods reveal deep phylogenetic structure with four strongly supported clades comprising snakes from New Guinea (I), localities all over Australia (II), the Kimberleys of Western Australia (III), and north-central Australia (IV), suggesting a much more ancient radiation than previously believed. This conclusion is robust to different molecular clock estimations indicating divergence in Pliocene or Late Miocene, after landbridge dispersal to New Guinea had occurred. While members of clades I, III and IV are medium-sized, slender snakes, those of clade II attain large sizes and a robust build, rendering them top predators in their ecosystems. Genetic differentiation within clade II is low and haplotype distribution largely incongruent with geography or colour morphs, suggesting Pleistocene dispersal and recent ecomorph evolution. Significant haplotype diversity exists in clades III and IV, implying that clade IV comprises two species. Members of clade II are broadly sympatric with members of both northern Australian clades. Thus, our data support the recognition of at least five species from within P. australis (auct.) under various criteria. We discuss biogeographical, ecological and medical implications of our findings.

Upper pliocene-lower pleistocene 40Ar/39Ar ages of Pudahuel ignimbrite (Diamante-Maipo volcanic complex), Central Chile (33.50S)

International Nuclear Information System (INIS)

Wall, R.M.; Lara, L.E.; Perez de Arce, C

2001-01-01

The Pudahuel Ignimbrite (Wall et al., 1996) is a characteristic pyroclastic flow deposit placed in the Central Depression, within the Maipo, Mapocho and Cachapoal valleys and, in the eastern side of the Andes, at Yaucha and Papagayos rivers as well (Harrington, 1989; Guerstein, 1993). Close to Santiago, Pudahuel Ignimbrite reaches 40 m in thickness (Dragicevic, 1962) which decreces up to 5 m 60 km to the west. The deposit is compounded by ash and lapilli size pumice within a cineritic matrix with shards, crystals and pumice fragments. Facies of both, laminar and turbulent flow regime can be distinguished, the latter prevailing near topographic barriers and on river plain floors. There, traction structures like cross-bedding and important amount of litic clasts are characteristic. Pumices are rhyolitic in composition (ca. 75% SiO 2 ; Stern et al., 1984; Guerstein, 1993) and have few 0.5-2 mm long biotite crystals. Two 40 Ar/ 39 Ar step-heating experiments on biotite from pumices of two localities, Maipu (Santiago) and Bollenar (Melipilla), show plateau ages of 2.3±0.3 Ma (RW-371) and 2.2±0.3 Ma (RW-1009). In both cases, the first step of the experiment indicates loss of Ar from the cristal rims wich was removed for the plateau calculus only in the second case. For the RW-371 sample an inverse isocrone age of 1.4±0.8 Ma (MSWD: 0.98) was obtained. Previously, the Pudahuel Ignimbrite was dated by Stern et al. (1984) in ca. 450 ka using zircon fission-tracks. Although inconsistent with our new ages, these pleistocene age seemed coherent with the discovery of an Antifer (deer) bone by Tavera (1978) within the ignimbrite close to Santiago. Nevertheless, as was apointed by Tavera (1978) himself, the Antifer genus is recognized in Argentina in the Pliocene-Quaternary interval and make possible a review of the well known 'pleistocene' mammal vertebrate associations in Chile. Another consequence of the new possible pliocene ages is that, since the ignimbrite does not show

Pliocene Te Aute limestones, New Zealand : expanding concepts for cool-water shelf carbonates

International Nuclear Information System (INIS)

Nelson, C.S.; Winefield, P.R.; Hood, S.D.; Caron, V.; Pallentin, A.; Kamp, P.J.J.

2003-01-01

Acceptance of a spectrum of warm- through cold-water shallow-marine carbonate facies has become of fundamental importance for correctly interpreting the origin and significance of all ancient platform limestones. Among other attributes, properties that have become a hallmark for characterising many Cenozoic non-tropical occurrences include: (1) the presence of common bryozoan and epifaunal bivalve skeletons; (2) a calcite-dominated mineralogy; (3) relatively thin deposits exhibiting low rates of sediment accumulation; (4) an overall destructive early diagenetic regime; and (5) that major porosity destruction and lithification occur mainly in response to chemical compaction of calcitic skeletons during moderate to deep burial. The Pliocene Te Aute limestones are non-tropical skeletal carbonates formed at paleolatitudes near 40-42 degrees S under the influence of commonly strong tidal flows along the margins of an actively deforming and differentially uplifting forearc basin seaway, immediately inboard of the convergent Pacific-Australian plate boundary off eastern North Island, New Zealand. This dynamic depositional and tectonic setting strongly influenced both the style and subsequent diagenetic evolution of the limestones. Some of the Te Aute limestones exhibit the above kinds of 'normal' non-tropical characteristics, but others do not. For example, many are barnacle and/or bivalve dominated, and several include attributes that at least superficially resemble properties of certain tropical carbonates. In this regard, a number of the limestones are infaunal bivalve rich and dominated by an aragonite over a calcite primary mineralogy, with consequently relatively high diagenetic potential. Individual limestone units are also often rather thick (e.g., up to 50-300 m), with accumulation rates from 0.2 to 0.5 m/ka, and locally as high as 1 m/ka. Moreover, there can be a remarkable array of diagenetic features in the limestones, involving grain alteration and

New technology for recycling materials from oily cold rolling mill sludge

Institute of Scientific and Technical Information of China (English)

Bo Liu; Shen-gen Zhang; Jian-jun Tian; De-an Pan; Ling Meng; Yang Liu

2013-01-01

Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of“hydrometallurgical treatment+hydrothermal synthesis”was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, eff ective, and economical technology off ers a new way to recycle oily CRM sludge.

New technology for recyclingmaterials from oily cold rollingmill sludge

Science.gov (United States)

Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Meng, Ling; Liu, Yang

2013-12-01

Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.

The Centers for Medicare and Medicaid Services (CMS) two midnight rule: policy at odds with reality.

Science.gov (United States)

Huntington, Ciara R; Blair, Laurel J; Cox, Tiffany C; Prasad, Tanushree; Kercher, Kent W; Augenstein, Vedra A; Heniford, B Todd

2016-02-01

To reduce costs, the Centers for Medicare and Medicaid Services (CMS) implemented new policies governing which patients are automatically admitted as inpatients (staying greater than "two midnights") and which require additional justification with physician documentation to be admitted. This study examines procedures missing from the Medicare Inpatient Only (MIO) list and uses national data to evaluate its appropriateness. Non-MIO procedures were identified from the current MIO list. Utilizing relevant billing codes, procedures were queried in the National Surgery Quality Improvement Program database for length of stay (LOS), percentage requiring >2 day stay, and inpatient status from 2005 to 2012. In addition, a separate analysis was performed for patients 65 years old or older who would qualify for Medicare. A majority of patients stayed more than 2 days for several procedures not included on the MIO list (% staying >2 days, mean LOS), including component separation (79.1%, 5.9 ± 12.3 days), diagnostic laparoscopy (64.2%, 5.5 ± 11.9 days), laparoscopic splenectomy (60.0%, 9.0 ± 13.6 days), open recurrent ventral hernia repair (58.2%, 6.3 ± 9.0 days), laparoscopic esophageal surgery (46.4%, 5.3 ± 13.3 days), and laparoscopic ventral hernia repair (24.7%, 2.5 ± 8.8 days). In patients ≥65 years, the average LOS was longer than the general population; for example, 40.2% of laparoscopic appendectomies and 38.7% of laparoscopic cholecystectomies in this older group required more than two nights in the hospital. In 92.3% of procedures examined, patients ≥65 years required greater than two nights in the hospital with an average LOS of 2.5-10.7 days. Commonly encountered non-MIO surgical procedures have national precedents for inpatient status. Before enacting policy, CMS and other regulatory bodies should consider current data to ensure rules are evidence-based and applicable.

The antler finds at Bilzingsleben, excavations 1969-1993

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Jürgen Vollbrecht

2000-09-01

Full Text Available 2820 antler remains from the Lower Palaeolithic site of Bilzingsleben, Thuringia, Germany (excavations 1969-1993 were the subject of detailed investigations. The two major goals were: 1.the consideration of taphonomic aspects 2.the critical evaluation of suggestions about artificial modifications to the antler material A detailed morphological description of the antler material provided the basis for the investigation. A prerequisite was the transfer of provenance data onto an x-y coordinate grid. Taphonomic aspects considered in this work include the relative frequencies of antler elements, estimates regarding the minimum number of individual deer, their age structure and seasonality, and, insofar as the condition of the antlers allowed, the classification of surface preservation, size classes and spatial distribution of the finds. The assemblage of antler finds, the majority of which seems to have come from red deer, is dominated by small fragments, mostly of tines. About one quarter of the finds are larger than 150 mm. Lower beams are more abundant than upper beams (e.g. crowns. Detailed counting, substantiated by systematic reconstruction, shows that in general the antlers are incomplete. After reconstruction of unshed antlers, it was possible to assess the minimum number of heads at 150 animals. Preliminary counting of postcranial and cranial (non antler cervid material points to about 70 cervids. Intentional accumulation of antlers by hominids can only be accepted as the reason for these disproportionate figures if other site formation processes can be ruled out. In fact, the correlation between sediment thickness and maximum antler densities, at least for finds smaller than 120mm, suggests that fluvial accumulation has to be taken into account as a probable element of the site formation history. Further, the mixture of unifacially abraded finds together with finds that exhibit bifacial abrasion points to a succession of changing fluvial

Reduced proliferation and osteocalcin expression in osteoblasts of male idiopathic osteoporosis.

Science.gov (United States)

Ruiz-Gaspà, Sílvia; Blanch-Rubió, Josep; Ciria-Recasens, Manuel; Monfort, Jordi; Tío, Laura; Garcia-Giralt, Natàlia; Nogués, Xavier; Monllau, Joan C; Carbonell-Abelló, Jordi; Pérez-Edo, Lluis

2010-03-01

Osteoporosis is characterized by low bone mineral density (BMD), resulting in increasing susceptibility to bone fractures. In men, it has been related to some diseases and toxic habits, but in some instances the cause of the primary--or idiopathic--osteoporosis is not apparent. In a previous study, our group compared histomorphometric measurements in cortical and cancellous bones from male idiopathic osteoporosis (MIO) patients to those of control subjects and found reduced bone formation without major differences in bone resorption. To confirm these results, this study analyzed the etiology of this pathology, examining the osteoblast behavior in vitro. We compared two parameters of osteoblast activity in MIO patients and controls: osteoblastic proliferation and gene expression of COL1A1 and osteocalcin, in basal conditions and with vitamin D(3) added. All these experiments were performed from a first-passage osteoblastic culture, obtained from osteoblasts that had migrated from the transiliac explants to the plate. The results suggested that the MIO osteoblast has a slower proliferation rate and decreased expression of genes related to matrix formation, probably due to a lesser or slower response to some stimulus. We concluded that, contrary to female osteoporosis, in which loss of BMD is predominantly due to increased resorption, low BMD in MIO seems to be due to an osteoblastic defect.

The geological, isotopic, botanical, invertebrate, and lower vertebrate contexts for aripithecus ramidus

Energy Technology Data Exchange (ETDEWEB)

Woldegabriel, Giday [Los Alamos National Laboratory; Ambrose, Stanley H [UNIV OF ILLINOIS; Barboni, Doris [CEREGE, FRANCE; Bonneffille, Raymond [CEREGE, FRANCE; Bremond, Laurent [MONTPELLIER, FRANCE; Currie, Brian [MIAMI UNIV, OXFORD, OHIO; Degusta, David [STANFORD UNIV.; Hart, William K [MIAMI UNIV, OXFORD, OHIO; Murray, Alison M [UNIV OF ALBERTA; Renne, Paul R [UC/BERKELEY; Jolly - Saad, M C [NANTERRE, FRANCE; Stewart, Kathlyn M [CANADA; White, Tim D [UC/BERKELEY

2009-01-01

Sediments containing Ardipithecus ramidus were deposited 4.4 million years ago on an alluvial floodplain in Ethiopia's western Afar rift. The Lower Aramis Member hominid-bearing unit, now exposed across a >9-kilometer structural arc, is sandwiched between two volcanic tuffs that have nearly identical {sup 40}Ar/{sup 39}Ar ages. Geological data presented here, along with floral, invertebrate, and vertebrate paleontological and taphonomic evidence associated with the hominids, suggest that they occupied a wooded biotope over the western three-fourths of the paleotransect. Phytoliths and oxygen and carbon stable isotopes of pedogenic carbonates provide evidence of humid cool woodlands with a grassy substrate.

Morphometric analysis of chameleon fossil fragments from the Early Pliocene of South Africa: a new piece of the chamaeleonid history.

Science.gov (United States)

Dollion, Alexis Y; Cornette, Raphaël; Tolley, Krystal A; Boistel, Renaud; Euriat, Adelaïde; Boller, Elodie; Fernandez, Vincent; Stynder, Deano; Herrel, Anthony

2015-02-01

The evolutionary history of chameleons has been predominantly studied through phylogenetic approaches as the fossil register of chameleons is limited and fragmented. The poor state of preservation of these fossils has moreover led to the origin of numerous nomen dubia, and the identification of many chameleon fossils remains uncertain. We here examine chameleon fossil fragments from the Early Pliocene Varswater formation, exposed at the locality of Langebaanweg "E" Quarry along the southwestern coast of South Africa. Our aim was to explore whether these fossil fragments could be assigned to extant genera. To do so, we used geometric morphometric approaches based on microtomographic imaging of extant chameleons as well as the fossil fragments themselves. Our study suggests that the fossils from this deposit most likely represent at least two different forms that may belong to different genera. Most fragments are phenotypically dissimilar from the South African endemic genus Bradypodion and are more similar to other chameleon genera such as Trioceros or Kinyongia. However, close phenetic similarities between some of the fragments and the Seychelles endemic Archaius or the Madagascan genus Furcifer suggest that some of these fragments may not contain enough genus-specific information to allow correct identification. Other fragments such as the parietal fragments appear to contain more genus-specific information, however. Although our data suggest that the fossil diversity of chameleons in South Africa was potentially greater than it is today, this remains to be verified based on other and more complete fragments.

Moessbauer spectroscopic study of corrosion products beneath primer coating containing anticorrosive pigments

International Nuclear Information System (INIS)

Kumar, A.V.R.; Nigam, R.K.

1998-01-01

The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Moessbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of non-stoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC > BLSC > ZP > MIO. (author)

Maturidade e Sucesso em Projetos sob a Perspectiva do Binômio Fornecedor e ClienteMaturity and Success in Projects from the Perspective if the Supplier and Customer BinomialMadurez y Éxito en Proyectos desde la Perspectiva del Binomio Proveedor y Cliente

Directory of Open Access Journals (Sweden)

JUNIOR RABECHINI, Roque

2010-03-01

Full Text Available RESUMOUma das preocupações que tem elevado a atenção de pesquisadores e profissionais de gestão nas empresas é a efetiva relação existente, no binômio fornecedor – cliente. Parece estar nos resultados dos projetos desenvolvidos, nessa via de mão dupla, o segredo do sucesso. Assim, quanto mais bem sucedidos forem os projetos que trafegam nessa via, em tese, melhor será a relação entre as partes. Entretanto, saber a exata capacidade em gerenciamento de projetos de ambas as partes é um desafio que pode ajudar a desvendar o entendimento deste fenômeno – caracterizado como sendo uma espécie de dueto da maturidade. Para entender como e quão é afinado esse dueto, este trabalho apresenta o resultado de uma pesquisa em que foram analisados 13 projetos, de 5 empresas, envolvidos no âmbito do binômio fornecedor – cliente. O estudo de múltiplos casos foi a opção escolhida para obter uma avaliação da maturidade das empresas em gerenciamento de projetos do referido binômio considerando-se os fatores internos de sucesso (custo, prazo e desempenho, bem como os fatores externos (utilidade, satisfação e eficácia. Como resultado foi possível verificar que, quanto maior a maturidade do fornecedor, maior a percepção de sucesso nos fatores internos, e quanto maior a maturidade do cliente, maior a percepção de sucesso nos fatores externos.ABSTRACTOne of the concerns that have accompanied the attention of business management researchers and professionals is the effective relationship in the binomial supplier - customer. The secret of a successful relationship seems to be in the results of projects developed in that two-way route. Thus, the most successful the projects that travel in this route are, in theory, the better the relationship between the parties. However, knowing the exact project management capacity from both sides is a challenge that can help unravel the understanding of this phenomenon - characterized as a kind of

Hydrogeochemistry and isotope geochemistry of Velenje Basin groundwater

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Tjaša Kanduč

2016-08-01

Full Text Available The geochemical and isotopic composition of groundwater in the Velenje Basin, Slovenia, was investigated between the years 2014 to 2015 to identify the geochemical processes in the major aquifers (Pliocene and Triassic and the water–rock interactions. Thirty-eight samples of groundwater were taken from the aquifers, 19 in the mine and 19 from the surface. Groundwater in the Triassic aquifer is dominated by HCO3–, Ca2+ and Mg2+ with δ13C DIC values in the range from -19.3 to -2.8 ‰, indicating degradation of soil organic matter and dissolution of carbonate minerals. In contrast, groundwater in the Pliocene aquifers is enriched in Mg2+, Na+, Ca2+, K+, and Si, and has high alkalinity, with δ13CDIC values in the range of -14.4 to +4.6 ‰. Based on the δ13CDIC values in all the aquifers (Pliocene and Triassic, both processes inflence the dissolution of carbonate minerals and dissolution of organic matter and in the Pliocene aquifers, methanogenesis as well. Based on Principal Component Analysis (PCA, and on geochemical and isotopic data we conclude that the following types of groundwater in Velenje Basin are present: Triassic aquifers with higher pH and lower conductivity and chloride, Pliocene, Pliocene 1 and Pliocene 2 aquifers with lower pH and higher conductivity and chloride contents, and Pliocene 3 and Pliocene 2, 3 aquifers with the highest pH values and lowest conductivities and chloride contents. 87Sr/86Sr tracer was used for the fist time in Slovenia to determine geochemical processes (dissolution of silicate versus carbonate fraction in Velenje Basin groundwater of different aquifers dewatering Pliocene and Triassic strata. 87Sr/86Sr values range from 0.70820 to 0.71056 in groundwater of Pliocene aquifers and from 0.70808 to 0.70910 in groundwater of the Triassic aquifer. This indicates that dissolution of the carbonate fraction prevails in both aquifers, while in Pliocene aquifers, an additional silicate weathering prevails with

Drilling Predation on Serpulid Polychaetes (Ditrupa arietina) from the Pliocene of the Cope Basin, Murcia Region, Southeastern Spain

Science.gov (United States)

Martinell, Jordi; Kowalewski, Michał; Domènech, Rosa

2012-01-01

We report quantitative analyses of drilling predation on the free-living, tube-dwelling serpulid polychaete Ditrupa arietina from the Cope Cabo marine succession (Pliocene, Spain). Tubes of D. arietina are abundant in the sampled units: 9 bulk samples from 5 horizons yielded ∼5925 specimens of D. arietina. Except for fragmentation, tubes were well preserved. Complete specimens ranged from 3.1 to 13.4 mm in length and displayed allometric growth patterns, with larger specimens being relatively slimmer. Drilled Ditrupa tubes were observed in all samples. Drillholes, identified as Oichnus paraboloides, were characterized by circular to elliptical outline (drillhole eccentricity increased with its diameter), parabolic vertical profile, outer diameter larger than inner diameter, penetration of one tube wall only, narrow range of drill-hole sizes, and non-random (anterior) distribution of drillholes. A total of 233 drilled specimens were identified, with drilling frequencies varying across horizons from 2.7% to 21% (3.9% for pooled data). Many tube fragments were broken across a drillhole suggesting that the reported frequencies are conservative and that biologically-facilitated (drill-hole induced) fragmentation hampers fossil preservation of complete serpulid tubes. No failed or repaired holes were observed. Multiple complete drillholes were present (3.9%). Drilled specimens were significantly smaller than undrilled specimens and tube length and drill-hole diameter were weakly correlated. The results suggest that drillholes were produced by a size-selective, site-stereotypic predatory organism of unknown affinity. The qualitative and quantitative patterns reported here are mostly consistent with previous reports on recent and fossil Ditrupa and reveal parallels with drilling patterns documented for scaphopod mollusks, a group that is ecologically and morphologically similar to Ditrupa. Consistent with previous studies, the results suggest that free-dwelling serpulid

Fator de retardamento e coeficiente de dispersão-difusão para o crômio (III em solos muito intemperizados, influenciados pelo pH, textura e matéria orgânica

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M. A. K. Alcântara

2001-03-01

Full Text Available O objetivo principal deste trabalho foi analisar a variação dos fatores de retardamento (R e dos coeficientes de dispersão-difusão (D para o crômio (III em dois solos muito intemperizados, considerando diferentes atributos edáficos: textura, pH e matéria orgânica. Utilizaram-se amostras dos horizontes A e B com diferença marcante no teor de matéria orgânica de dois solos coletados no estado de São Paulo: Latossolo Vermelho eutroférrico textura argilosa (LVe e Latossolo Vermelho-Amarelo distrófico textura média (LVd. A alteração do pH das amostras do horizonte superficial foi realizada com adição de carbonato de cálcio para elevar a saturação por bases a 70%. Foram realizados experimentos de adsorção em condições estáticas e de lixiviação em colunas de solo, utilizando a teoria do deslocamento miscível. Os Rs obtidos para o LVe foram maiores em comparação aos obtidos para o LVd. O aumento do pH do solo propiciado pela adição de carbonato de cálcio resultou em aumento no R. No LVe, a presença significativa de ácidos fúlvicos na matéria orgânica propiciou um R menor no horizonte superficial em relação ao subsuperficial. Não foi evidenciada relação nítida entre D e os diferentes solos, níveis de calagem e horizontes.

Pliocene-Lower Pleistocene shallow-water mixed siliciclastics and carbonates (Yanigua and Los Haitises formations) in eastern Hispaniola (Dominican Republic)

Science.gov (United States)

Braga, Juan C.; Díaz de Neira, Alberto; Lasseur, Eric; Mediato, José; Aguirre, Julio; Abad, Manuel; Hernaiz-Huerta, Pedro P.; Monthel, Jacques; Pérez-Valera, Fernando; Lopera, Eusebio

2012-07-01

The virtually unfolded sedimentary cover of the Cordilleras Central and Oriental in the eastern Dominican Republic (eastern Hispaniola, tropical North Atlantic) largely consists of Pliocene to Early Pleistocene mixed siliciclastics and carbonates. These deposits have been grouped into two laterally interfingering mapping units, the Yanigua and Los Haitises formations. The former (mainly siliciclastics) comprises marl, marly limestone, and minor conglomerate, sandstone, lignite, and carbonaceous clay and crops out closest to the basement. The Los Haitises Formation mainly consists of limestone and intercalating beds of marly limestone and marl. Lithological mapping at the 1:50,000 scale and facies analysis of twelve measured sections and of additional fourteen outcrops suggest that these deposits mainly formed on a shallow-water marine platform fringing the precursor reliefs of the Cordillera Oriental and the southeastern end of the Cordillera Central. Only a limited proportion of sediment formed in floodplains and marshes. Marl and marly limestone dominated the inner platform sediments. Terrigenous mud decreased away from the emergent basement and carbonate sedimentation dominated the more external platform. Corals, molluscs, echinoids, foraminifers, bryozoans, coralline algae, and Halimeda are the main components with varying amounts of carbonate mud. The platform was generally a low-energy environment with seagrass patches. In the inner platform, corals grew as isolated colonies or as small patch reefs dominated by Porites in marly and bioclastic substrates. Branching corals (Stylophora and Acropora) grew in extensive carpets in more distal areas. At least in the last stage of its development (Early Pleistocene), the platform was rimmed by a reef barrier similar to the Holocene Caribbean barrier reefs, with Acropora gr. palmata, A. cervicornis, Porites, Montastrea, Siderastrea, and Diploria as the main reef builders.

Sedimentary architecture and depositional controls of a Pliocene river-dominated delta in the semi-isolated Dacian Basin, Black Sea

Science.gov (United States)

Jorissen, Elisabeth L.; de Leeuw, Arjan; van Baak, Christiaan G. C.; Mandic, Oleg; Stoica, Marius; Abels, Hemmo A.; Krijgsman, Wout

2018-06-01

Sedimentological facies models for (semi-)isolated basins are less well developed than those for marine environments, but are critical for our understanding of both present-day and ancient deltaic sediment records in restricted depositional environments. This study considers an 835 m thick sedimentary succession of mid-Pliocene age, which accumulated in the Dacian Basin, a former embayment of the Black Sea. Detailed sedimentological and palaeontological analyses reveal a regression from distal prodelta deposits with brackish water faunas to delta-top deposits with freshwater faunas. Sediments contain frequent hyperpycnal plumes and an enrichment in terrestrial organic material, ichnofossils and in situ brackish and freshwater faunas. Deltaic progradation created thin, sharply-based sand bodies formed by multiple terminal distributary channels, covering a wide depositional area. The system experienced frequent delta-lobe switching, resulting in numerous thin parasequences. Parasequences are overlain by erosive reddish oxidized sand beds, enriched in broken, abraded brackish and freshwater shells. These beds were formed after sediment starvation, on top of abandoned delta lobes during each flooding event. A robust magnetostratigraphic time frame allowed for comparison between the observed sedimentary cyclicity and the amplitude and frequency of astronomical forcing cycles. Our results indicate that parasequence frequencies are significantly higher than the number of time equivalent astronomical cycles. This suggests that delta-lobe switching was due to autogenic processes. We consider the observed facies architecture typical for a delta prograding on a low-gradient slope into a shallow, brackish, protected, semi-isolated basin. Furthermore, in the absence of significant wave and tidal influence, sediment progradation in such a protected depositional setting shaped a delta, strongly river-dominated.

Guarani Paraguayo [Encyclopedia entry

OpenAIRE

Drude, S.

2005-01-01

Guaraní , Paraguaisches Guaraní, Eigen-Bez. Avañe’ẽ, Sprache in Paraguay (über 3,5 Mio. Sprecher, 95 % der Bev.), NO-Argentinien (bis zu 1 Mio. Sprecher) und S-Brasilien. Das zu den Tupí-Guaraní-Sprachen zählende G. ist eine der größten → Indianersprachen S-Amerikas (nach Ketschua und vor Aimara) und die einzige, die überwiegend von Nicht-Indianern gebraucht wird. Seit den 1990-Jahren ist das G. in Paraguay als Nationalsprache anerkannt und wird auch in Schulen verwendet. Das G. wurde durch d...

Capitolo IV. Socialismo utopico?

OpenAIRE

Gatto, Marco

2016-01-01

Io devo stare nell’isolamento. È assolutamente assurdo credere che uno come me possa tanto facilmente rinunciare a tutto ciò che è e scomparire tra la massa. La massa riconosce ben presto queste balordaggini e ti distrugge o cerca comunque di distruggerti. La massa espelle una persona come me che si è messa nelle sue mani al cento per cento, senza pietà, come un corpo estraneo. Il mio posto non è tra la massa, se do retta alla massa il mio posto è dentro di me, se do retta a me stesso. Visto ...

La spazialità dell’ascolto

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Cristina Mattiucci

2008-12-01

Full Text Available Hanno sistemato il mio computer da una settimana... finalmente l’audio funziona di nuovo! Ora sì che va meglio. Arrivo e mi metto le cuffie, ancora prima di scorrere l’archivio sul mio desktop. È un gesto che fanno quasi tutti intorno a me. È come se cercassero un’altra stanza all’interno di questa grande stanza che condividiamo. Ognuno si ritaglia nello spazio delle proprie orecchie il posto dove vorrebbe essere, più congeniale al lavoro quotidiano o dove, più semplicemente, ci si concentri meglio.

Rb/Sr ages of metamorphites of the Herbert Mountains, Shackleton Range, Antarctica

International Nuclear Information System (INIS)

Hofmann, J.; Pilot, J.; Schlichting, M.

1981-01-01

Results of Rb/Sr-age determinations from six mica schists, sampled in the upper part of the Shackleton metamorphic complex (Herbert Mountains, Shackleton Range, Antarctica) are reported. A three point isochrone gives an age of 470 +- 36 mio. yrs., a two point isochrone an age of 1414 +- 185 mio yrs. The first age marks a thermo-magmatic activation of early paleozoic age, the second one is interpretated as the age of regional metamorphism from the upper parts of the Shackleton metamorphic complex. The results are discussed under consideration of former age determinations. (author)

La châine andine du Pérou Central: chronologie, orientation et styles des phases tectoniques du Tertiaire Supérieur - Aperçus sur la Tectonique Quaternaire

Directory of Open Access Journals (Sweden)

1975-01-01

fase de deformaciones quebradizas del plioceno, según una dirección de acortamiento N 090 (entre 8 y 4,5 M A. Una fase mioceno reciente (entre 14 y 10,5 M.A. con dirección N 000 en las Altas Mesetas y quizás de dirección N 045 en la Cordillera Occidental da deformaciones quebradizas pero con una ligera tectónica flexible La fase mioceno antiguo (entre 21 y 14 M.A. está caracterizada por una dirección N 045, estructuras quebradizas y anchas estructuras flexibles. La fase oligoceno inferior (entre 21,5 y 40 M.A. concierne a esfuerzos mucho más importantes en estructuras mas profundas. Las fases mioceno y plioceno están superpuestas. El estudio de la falla de Gran Bretaña confirma estos resultados sin que se pueda tener la prueba de dos fases mioceno se trata de un accidente de descolgamiento con escasos desechos horizontales. Las fallas de la zona de La Oroya-Junín-Tarma tienen una geometría semejante al accidente de Gran Bretaña: se pueden observar tres fases sin que sea posible darles una fecha pero sus características corresponden a las fases plioceno, mioceno y oligoceno inferior. Algunas observaciones en la Cordillera Blanca parecen relacionarse a las del Sur de Huancavelica, pero quedan por precisar. El cuaternario muestra una tectónica compresiva de direcciones N 130 en la Cordillera Blanca y San Ramón, N 000 y N 040 en la cuenca de Huancayo (eventualmente también N 075 siguiendo la edad de la formación Jauja. No se ha observado fallas normales mas que en la Cordillera Blanca (¿distensión? ¿subida del macizo granítico?. The mio-pliocene tectonic episodes are studied in many sectors of the Central Peruvian Andes South of Huancavelica (Choclococha, Huachocolpa, Lircay, a pliocene episode of breaking compression but with a light folding tectonic The ancient miocene episode (between 8 and 4.5 m y.. A recent miocene episode (between 14 and 105 m.y of direction N 000 in the High Plateaux and may be of direction N 045 in the western chain of

A articulação acrômio-clavicular como ponto de referência alternativo para o nível flebostático La articulación acromion-clavicular como punto de referencia alternativo para el nivel flebostático Acromion-clavicular joint as an alternative reference point for the phlebostatic level

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Getúlio Rodrigues de Oliveira Filho

2001-12-01

Full Text Available JUSTIFICATIVA E OBJETIVOS: O nível flebostático corresponde ao ponto médio do diâmetro ântero-posterior do tórax, ao nível do 4º espaço intercostal e constitui-se no ponto de referência padrão para o nível zero da pressão venosa central. Freqüentemente, durante anestesia, o acesso à face lateral do tórax é impossível. Este estudo teve por objetivo, derivar uma equação que possibilite a estimativa do nível flebostático a partir de variáveis antropométricas e da altura da articulação acrômio-clavicular. MÉTODO: Foram estudados 200 pacientes. O grupo 1 foi utilizado para derivação da equação e o grupo 2, para sua validação. Foram coletados dados antropométricos. O nível flebostático e a altura da articulação acrômio-clavicular foram medidos em decúbito dorsal. Regressão linear múltipla foi utilizada no grupo 1, tendo como variável dependente o nível flebostático, e independentes, as variáveis antropométricas e a altura da articulação acrômio-clavicular. No grupo 2, a concordância entre os valores do eixo flebostático observados e preditos pela equação foi testada pelo método de Bland-Altman. RESULTADOS: A equação resultante do grupo 1 foi: nível flebostático = 49,57 + (0,19 x Idade + (0,31 x Peso + (0,20 x altura da articulação acrômio-clavicular. A diferença média entre os valores preditos e observados do nível flebostático, no grupo 2 foi de 2,79 ± 7,62 mm. CONCLUSÕES: A equação apresentada neste estudo pode prever com precisão o ponto flebostático.JUSTIFICATIVA Y OBJETIVOS: El nivel flebostático corresponde al punto medio del diámetro antero-posterior del tórax, al nivel del 4º espacio intercostal y se constituye en el punto de referencia patrón para el nivel cero de la presión venosa central. Frecuentemente, durante anestesia, el acceso a la fase lateral del tórax es imposible. Este estudio tuvo por objetivo, derivar una ecuación que posibilite la estimativa del

Taphonomy of a thick Terebratula bioherm from the Pliocene of southeastern Spain

Science.gov (United States)

García-Ramos, Diego A.

2015-04-01

Brachiopods were extremely abundant during the Paleozoic era but underwent a dramatic loss of biodiversity at the Permo-Triassic boundary. The comparison of brachiopod and bivalve diversity through geological time shows that the latter were the most successful counterpart at best recovering from mass extinction events. Nonetheless, there are cases where Post-Paleozoic brachiopods stand out as the dominant marine benthos in particular environments, forming paucispecific brachiopod-dominated bioherms. This note describes an example of shallow-water brachiopod bioherm dominated by the terebratulid Terebratula calabra. The shell bed is found in mixed siliciclastic-temperate carbonate deposits of late Early Pliocene age nearby Águilas (southeastern Spain). This unique brachiopod concentration may be helpful to understand the particular success of large-sized brachiopods like Terebratula in Cenozoic environments typically dominated by bivalves. The bioherm attains 1.5 meters in thickness and crops out along a band up to 140 meters wide. The lithology consists of bioturbated fine-grained sands containing poorly sorted bioclasts, mostly fragments of Terebratula. This shell bed also records a diverse fauna, including five brachiopod genera, pectinids (4 genera), oysters (3 genera), in addition to rare gastropods, echinoids, bryozoans, etc. The density and sorting of bioclasts is laterally variable, and the biofabrics range from loosely dispersed to densely-packed, including examples of concave-up vertical stacking and nesting of shells. Most of the fragments of Terebratula preserve the posterior part of the shell only. These fragments generally display corrasion (rounded fractured margins, rounded to completely missing symphytium), bioerosion (prevailing the ichnogenera Entobia, Gnathichnus and Podichnus) and encrustation (mainly by bryozoans, Ancistrocrania, and Pododesmus). The good preservation of Pododesmus contrasts with that of most fragments of Terebratula, although

Observações citológicas em Coffea: XV - Microsporogênese em Coffea arabica L.

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A. J. T. Mendes

1950-03-01

Full Text Available No presente trabalho são apresentadas as observações realizadas sôbre a microsporogênese nas variedades semperflorens e caturra, de Coffea arabica L. Notou-se que, no início da prófase, os cromossômios se colorem muito mal, não permitindo observações sôbre a sua morfologia; em paquitene, os cromossômios se apresentam com várias secções heteropicnóticas separadas por secções muito finas, que se colorem mal; o centrômero é bastante nítido e se acha ladeado de zonas bem heteropicnóticas; as extremidades dos braços dos cromossômios se colorem mal e se perdem no meio do citoplasma ; o nucléolo é bastante visível e a êle se acham ligados alguns cromossômios. É difícil determinar o número exato de cromossômios ligados ao nucléolo, tendo-se encontrado de 1 a 4. De paquitene a metáfase I, as fases se sucedem rapidamente. Em diplotene, os cromossômios são curtos, não mais se percebendo o centrômero. Em diaquinese os 22 pares de cromossômios se repelem pela sua parte mais colorida, onde se encontra o centrômero, e se unem pela parte clara, onde se notam os quiasmas ; o número de quiasmas, por célula, varia de 29 a 43 ; a média por bivalente é de 1,67, em semperjlorens, e 1,75, em caturra. Em metáfase I, o número médio de quiasmas, por bivalente,. é de 1,69, em semperjlorens, e 1,67, em caturra. Em anáfase I, os 22 pares de cromossômios se separam normalmente. Em telófase I, os cromossômios se colorem mal. Não há, praticamente, intercinese; os cromossômios contraem-se de novo e entram em anáfase II. A formação dos micrósporos é normal. Depois de soltos, ocorre a divisão nuclear, dando origem a dois núcleos com 22 cromossômios. Isto ocorre três a quatro dias antes da abertura das flores; o núcleo vegetativo é grande, esférico e homogêneo, colo-rindo-se mal; o núcleo reprodutivo é menor, reticulado, colore-se bem e se localiza na periferia da célula; ao seu redor se destaca uma por

Plio-quaternary deposits in the Eastern Rharb (Nw Morocco): Electrosequential characterization

Science.gov (United States)

Al Mazini, Imane; Mridekh, Abdelaziz; Kili, Malika; El Mansouri, Bouâbid; El Bouhaddioui, Mohamed; Magrane, Bouchaib

2018-02-01

The Rharb basin, of which our study area is part, is located at the western extremity of the south Rif corridor. It corresponds to a subsiding zone that appeared in the Upper Miocene, between two major structural domains: the Rif to the north and east and the Meseta domain to the south. The eastern part of this basin is characterized by a Plio-Quaternary continental fill. Its geographical position and its structural and paleo-environmental contexts are reflected by a great facies heterogeneity. This work aims to image the subsurface structure and to characterize the distribution mode of Plio-Quaternary deposits of the eastern Rharb. The use of a database consisting of geo-electrical cross sections, hydrogeological drilling and wireline logging integrated in a Geographic Information System (GIS) allowed us to establish a new three-dimensional model of the top of the Mio-Pliocene substratum, new geo-electrical cross sections, as well as the isopach maps of lower, intermediate, upper and superficial geo-electric interval. This approach allowed us to characterize the Plio-Quaternary deposits of the study area and to highlight the effects of the tectonic regime and the relative sea level fluctuations on the sequential organization of these deposits. Our new model shows the development of prograding, aggrading and retrograding parasequences denoting the existence of autogenic mechanisms in the organization of plio-quaternary deposits of the eastern part of the Rharb basin. Therefore, it opens new perspectives for the exploration of water resources and monitoring their quality throughout the basin.

Comparison of open reduction versus minimally invasive surgical approaches on screw position in canine sacroiliac lag-screw fixation.

Science.gov (United States)

Déjardin, Loïc M; Marturello, Danielle M; Guiot, Laurent P; Guillou, Reunan P; DeCamp, Charles E

2016-07-19

To compare accuracy and consistency of sacral screw placement in canine pelves treated for sacroiliac luxation with open reduction and internal fixation (ORIF) or minimally invasive osteosynthesis (MIO) techniques. Unilateral sacroiliac luxations created experimentally in canine cadavers were stabilized with an iliosacral lag screw applied via ORIF or MIO techniques (n = 10/group). Dorsoventral and craniocaudal screw angles were measured using computed tomography multiplanar reconstructions in transverse and dorsal planes, respectively. Ratios between pilot hole length and sacral width (PL/SW-R) were obtained. Data between groups were compared statistically (p sacroiliac luxations provides more accurate and consistent sacral screw placement than ORIF. With proper techniques, iatrogenic neurological damage can be avoided with both techniques. The PL /SW-R, which relates to safe screw fixation, also demonstrates that screw penetration of at least 60% of the sacral width is achievable regardless of surgical approach. These findings, along with the limited dissection needed for accurate sacral screw placement, suggest that MIO of sacroiliac luxations is a valid alternative to ORIF.

SEDIMENTATION AND BASIN-FILL HISTORY OF THE PLIOCENE SUCCESSION EXPOSED IN THE NORTHERN SIENA-RADICOFANI BASIN (TUSCANY, ITALY: A SEQUENCE-STRATIGRAPHIC APPROACH

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IVAN MARTINI

2017-08-01

Full Text Available Basin-margin paralic deposits are sensitive indicators of relative sea-level changes and typically show complex stratigraphic architectures that only a facies-based sequence-stratigraphic approach, supported by detailed biostratigraphic data, can help unravel, thus providing constraints for the tectono-stratigraphic reconstructions of ancient basins. This paper presents a detailed facies analysis of Pliocene strata exposed in a marginal key-area of the northern Siena-Radicofani Basin (Tuscany, Italy, which is used as a ground for a new sequence-stratigraphic scheme of the studied area. The study reveals a more complex sedimentary history than that inferred from the recent geological maps produced as part of the Regional Cartographic Project (CARG, which are based on lithostratigraphic principles. Specifically, four sequences (S1 to S4, in upward stratigraphic order have been recognised, each bounded by erosional unconformities and deposited within the Zanclean-early Gelasian time span. Each sequence typically comprises fluvial to open marine facies, with deposits of different sequences that show striking lithological similarities.The architecture and internal variability shown by the studied depositional sequences are typical of low-accommodation basin-margin settings, that shows: i a poorly-developed to missing record of the falling-stage systems tract; ii a lowstand system tract predominantly made of fluvio-deltaic deposits; iii a highstand system tract with substantial thickness variation between different sequences due to erosional processes associated with the overlying unconformity; iv a highly variable transgressive system tract, ranging from elementary to parasequential organization.

La morphologie karstique dans le canyon de la Cèze et sur le plateau de Méjannes-le-Clap (Garrigues nord, Gard, France – Rapports avec l'évolution paléogéographique mio-pliocène

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Claude Martin

2008-03-01

is clear that Messinian retrogressive erosion stopped at the edge of the Rhône valley. Therefore, the incision of the Cèze canyon predates the Messinian. It goes back certainly to the superior Burdigalian, in agreement with the model of evolution proposed by D. BESSON (2005 for the "Rhodano-Provençal" basin. This incision was followed in the Miocene by two phases of removing sediment (infra-Tortonian and Messinian, each occurring after a phase of filling.Traces left by lithophagous molluscs after flooding of the canyon during the Pliocene transgression can be found at various elevations between 135 and 160 m, due to later tectonic movements. During the Pliocene, the canyon filled up with land deposits that subsist today in the form of mostly quartzose pebbles embedded in reddish matrix rock, up to elevations of 245 m. Outliers of Pliocene alluvial formations subsist on shoulders and benches that are remnants from the Cèze canyon's different hollowing phases. Some of these topographical elements include subhorizontal karst systems at elevations of 180-220 m asl. The cavities with ascending passages that emerge by shafts at an altitude near 280 m are linked, for their part, to the Miocene transgression and/or filling phases.The most useful information about the sector's Messinian and Pliocene evolution is provided by other karst systems composed of subhorizontal and inclined passages with connecting-shafts. As with the Saint-Marcel Cave in Ardèche (L. MOCOCHAIN et al., 2006-a, 2006-b, these systems are the result of ascending karst genesis. The subhorizontal passages located at about 100 m asl under the Méjannes-le-Clap plateau must be interpreted in relation to the level reached by the Cèze canyon after it was hollowed out. These passages are currently functional, the base level being only a few metres below the level of superior Miocene hollowing. The Pliocene transgression caused karst formation to shift upwards to 140­150-m asl. Some of the systems

Osteometrical and functional analysis and evolution of autopodia in the genus Homo

Czech Academy of Sciences Publication Activity Database

Nývltová Fišáková, Miriam

2003-01-01

Roč. 49, - (2003), s. 107-109 ISSN 1210-048X Institutional research plan: CEZ:AV0Z8001916 Keywords : Pleistocene * Fossil Hominids * Palaeolithic Subject RIV: AC - Archeology, Anthropology, Ethnology

Millennial-scale climate variations recorded in Early Pliocene colour reflectance time series from the lacustrine Ptolemais Basin (NW Greece)

Science.gov (United States)

Steenbrink, J.; Kloosterboer-van Hoeve, M. L.; Hilgen, F. J.

2003-03-01

Quaternary climate proxy records show compelling evidence for climate variability on time scales of a few thousand years. The causes for these millennial-scale or sub-Milankovitch cycles are still poorly understood, not least due to the complex feedback mechanisms of large ice sheets during the Quaternary. We present evidence of millennial-scale climate variability in Early Pliocene lacustrine sediments from the intramontane Ptolemais Basin in northwestern Greece. The sediments are well exposed in a series of open-pit lignite mines and exhibit a distinct millennial-scale sedimentary cyclicity of alternating lignites and lacustrine marl beds that resulted from precession-induced variations in climate. The higher-frequency, millennial-scale cyclicity is particularly prominent within the grey-coloured marl segment of individual cycles. A stratigraphic interval of ˜115 ka, covering five precession-induced sedimentary cycles, was studied in nine parallel sections from two open-pit lignite mines located several km apart. High-resolution colour reflectance records were used to quantify the within-cycle variability and to determine its lateral continuity. Much of the within-cycle variability could be correlated between the parallel sections, even in fine detail, which suggests that these changes reflect basin-wide variations in environmental conditions related to (regional) climate fluctuations. Interbedded volcanic ash beds demonstrate the synchronicity of these fluctuations and spectral analysis of the reflectance time series shows a significant concentration of within-cycle variability at periods of ˜11, ˜5.5 and ˜2 ka. The occurrence of variability at such time scales at times before the intensification of the Northern Hemisphere glaciation suggests that they cannot solely have resulted from internal ice-sheet dynamics. Possible candidates include harmonics or combination tones of the main orbital cycles, variations in solar output or periodic motions of the Earth

The role of sediment supply in large-scale stratigraphic architecture of ancient Gilbert-type deltas (Pliocene Siena-Radicofani Basin, Italy)

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Martini, Ivan; Ambrosetti, Elisa; Sandrelli, Fabio

2017-04-01

Aggradation, progradation and retrogradation are the main patterns that define the large-scale architecture of Gilbert-type deltas. These patterns are governed by the ratio between the variation in accommodation space and sediment supply experienced during delta growth. Sediment supply variations are difficult to estimate in ancient settings; hence, it is rarely possible to assess its significance in the large-scale stratigraphic architecture of Gilbert-type deltas. This paper presents a stratigraphic analysis of a Pliocene deltaic complex composed of two coeval and narrowly spaced deltaic branches. The two branches recorded the same tectonic- and climate-induced accommodation space variations. As a result, this deltaic complex represents a natural laboratory for testing the effects of sediment supply variations on the stratigraphic architecture of Gilbert-type deltas. The field data suggest that a sediment supply which is able to counteract the accommodation generated over time promotes the aggradational/progradational attitude of Gilbert-type deltas, as well as the development of thick foreset deposits. By contrast, if the sediment supply is not sufficient for counterbalancing the generated accommodation, an aggradational/retrogradational stratigraphic architecture is promoted. In this case, the deltaic system is forced to withdraw during the different phases of generation of accommodation, with the subsequent flooding of previously deposited sub-horizontal topset deposits (i.e., the delta plain). The subsequent deltaic progradation occurs above these deposits and, consequently, the available space for foresets growth is limited to the water depth between the base-level and the older delta plain. This leads to the vertical stacking of relatively thin deltaic deposits with an overall aggradatational/retrogradational attitude.

Flow in the western Mediterranean shallow mantle: Insights from xenoliths in Pliocene alkali basalts from SE Iberia (eastern Betics, Spain)

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Hidas, Károly; Konc, Zoltán.; Garrido, Carlos J.; Tommasi, Andréa.; Vauchez, Alain; Padrón-Navarta, José Alberto; Marchesi, Claudio; Booth-Rea, Guillermo; Acosta-Vigil, Antonio; Szabó, Csaba; Varas-Reus, María. Isabel; Gervilla, Fernando

2016-11-01

Mantle xenoliths in Pliocene alkali basalts of the eastern Betics (SE Iberia, Spain) are spinel ± plagioclase lherzolite, with minor harzburgite and wehrlite, displaying porphyroclastic or equigranular textures. Equigranular peridotites have olivine crystal preferred orientation (CPO) patterns similar to those of porphyroclastic xenoliths but slightly more dispersed. Olivine CPO shows [100]-fiber patterns characterized by strong alignment of [100]-axes subparallel to the stretching lineation and a girdle distribution of [010]-axes normal to it. This pattern is consistent with simple shear or transtensional deformation accommodated by dislocation creep. One xenolith provides evidence for synkinematic reactive percolation of subduction-related Si-rich melts/fluids that resulted in oriented crystallization of orthopyroxene. Despite a seemingly undeformed microstructure, the CPO in orthopyroxenite veins in composite xenoliths is identical to those of pyroxenes in the host peridotite, suggesting late-kinematic crystallization. Based on these observations, we propose that the annealing producing the equigranular microstructures was triggered by melt percolation in the shallow subcontinental lithospheric mantle coeval to the late Neogene formation of veins in composite xenoliths. Calculated seismic properties are characterized by fast propagation of P waves and polarization of fast S waves parallel to olivine [100]-axis (stretching lineation). These data are compatible with present-day seismic anisotropy observations in SE Iberia if the foliations in the lithospheric mantle are steeply dipping and lineations are subhorizontal with ENE strike, implying dominantly horizontal mantle flow in the ENE-WSW direction within vertical planes, that is, subparallel to the paleo-Iberian margin. The measured anisotropy could thus reflect a lithospheric fabric due to strike-slip deformation in the late Miocene in the context of WSW tearing of the subducted south Iberian margin

A new species of Nyanzachoerus (Cetartiodactyla: Suidae from the late Miocene Toros-Ménalla, Chad, central Africa.

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Jean-Renaud Boisserie

Full Text Available During the latest Miocene and the early Pliocene, tetraconodontine suids were the most predominant large omnivorous mammals in Africa. Yet, new species were often identified on the grounds of limited evidence, a situation impacting their value for biochronological correlations as well as for environmental and biogeographical reconstructions. The description of the most abundant known collection of craniodental remains attributed to the tetraconodontine Nyanzachoerus helps to improve this situation. These specimens were collected in the upper Miocene deposits at Toros-Ménalla, northern Chad, central Africa, by the Mission Paléoanthropologique Franco-Tchadienne. We compared them with Nyanzachoerus from eastern and southern Africa, using extant species as a reference for patterns of morphological variation. Thanks to a large sample of observations, our work focused as much on craniomandibular morphology as on dental morphology and metrics (improved by an index scoring for the complexity of distal third molars and a detailed investigation of premolar-molar ratios. We recognized two taxa at Toros-Ménalla: Nyanzachoerus khinzir nov. sp. and Ny. cf. australis. We also revised the taxonomic status for other species, including: the restriction of Ny. syrticus to its holotype specimen from Sahabi (Libya, the resurrection of the nomen Ny. tulotos, and the synonymy of Ny. kuseralensis with Ny. waylandi. At Toros-Ménalla, Ny. khinzir was the only suid coexisting with the anthracotheriid Libycosaurus and the hominid Sahelanthropus, whereas Ny. cf. australis was associated with a different, probably younger faunal context. Nyanzachoerus. khinzir, which probably had a diversified diet, supports a latest Miocene biogeographical distinction between central Africa and eastern Africa.

Dragon's paradise lost: palaeobiogeography, evolution and extinction of the largest-ever terrestrial lizards (Varanidae.

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Scott A Hocknull

Full Text Available BACKGROUND: The largest living lizard species, Varanus komodoensis Ouwens 1912, is vulnerable to extinction, being restricted to a few isolated islands in eastern Indonesia, between Java and Australia, where it is the dominant terrestrial carnivore. Understanding how large-bodied varanids responded to past environmental change underpins long-term management of V. komodoensis populations. METHODOLOGY/PRINCIPAL FINDINGS: We reconstruct the palaeobiogeography of Neogene giant varanids and identify a new (unnamed species from the island of Timor. Our data reject the long-held perception that V. komodoensis became a giant because of insular evolution or as a specialist hunter of pygmy Stegodon. Phyletic giantism, coupled with a westward dispersal from mainland Australia, provides the most parsimonious explanation for the palaeodistribution of V. komodoensis and the newly identified species of giant varanid from Timor. Pliocene giant varanid fossils from Australia are morphologically referable to V. komodoensis suggesting an ultimate origin for V. komodoensis on mainland Australia (>3.8 million years ago. Varanus komodoensis body size has remained stable over the last 900,000 years (ka on Flores, a time marked by major faunal turnovers, extinction of the island's megafauna, the arrival of early hominids by 880 ka, co-existence with Homo floresiensis, and the arrival of modern humans by 10 ka. Within the last 2000 years their populations have contracted severely. CONCLUSIONS/SIGNIFICANCE: Giant varanids were once a ubiquitous part of Subcontinental Eurasian and Australasian faunas during the Neogene. Extinction played a pivotal role in the reduction of their ranges and diversity throughout the late Quaternary, leaving only V. komodoensis as an isolated long-term survivor. The events over the last two millennia now threaten its future survival.

Neanderthal teeth from Moula-Guercy, Ardèche, France.

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Hlusko, Leslea J; Carlson, Joshua P; Guatelli-Steinberg, Debbie; Krueger, Kristin L; Mersey, Ben; Ungar, Peter S; Defleur, Alban

2013-07-01

Here we describe dental remains from a Neanderthal fossil assemblage from Moula-Guercy, France. Our report demonstrates that the Moula-Guercy hominid remains contribute important morphological, developmental, and behavioral data to understanding Neanderthal evolutionary history. We include gross comparative morphological descriptions and enamel surface microstructure and microwear data. These teeth reveal numerous characteristics that are diagnostic of Neanderthals and provide no evidence for the presence of any other hominid taxa. Enamel growth increment data from the Moula-Guercy specimens yield evidence of a Neanderthal pattern of development, although at the lower end of the range of variation. The presence of a significant number of linear enamel hypoplasias indicates that these individuals were stressed during childhood. Molar microwear data suggest that these Neanderthals did not differ significantly from modern humans in terms of the fracture properties of the food they were consuming. The incisor microwear and macro striations provide evidence that these individuals may have been using their anterior teeth as tools, similar to the practices of several modern human populations such as the Inuit, Ipiutak, and Australian Aboriginals, and reminiscent of evidence from other Neanderthals from Krapina, Croatia, as well as the 600,000 year old hominids from Sima de los Huesos, Spain. Am J Phys Anthropol 151:477-491, 2013.© 2013 Wiley Periodicals, Inc. Copyright ©2013 Wiley Periodicals, Inc.

Cranial base morphology and temporal bone pneumatization in Asian Homo erectus.

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Balzeau, Antoine; Grimaud-Hervé, Dominique

2006-10-01

The external morphological features of the temporal bone are used frequently to determine taxonomic affinities of fossils of the genus Homo. Temporal bone pneumatization has been widely studied in great apes and in early hominids. However, this feature is rarely examined in the later hominids, particularly in Asian Homo erectus. We provide a comparative morphological and quantitative analysis of Asian Homo erectus from the sites of Ngandong, Sambungmacan, and Zhoukoudian, and of Neandertals and anatomically modern Homo sapiens in order to discuss causes and modalities of temporal bone pneumatization during hominid evolution. The evolution of temporal bone pneumatization in the genus Homo is more complex than previously described. Indeed, the Zhoukoudian fossils have a unique pattern of temporal bone pneumatization, whereas Ngandong and Sambungmacan fossils, as well as the Neandertals, more closely resemble the modern human pattern. Moreover, these Chinese fossils are characterized by a wide midvault and a relatively narrow occipital bone. Our results support the point of view that cell development does not play an active role in determining cranial base morphology. Instead, pneumatization is related to available space and to temporal bone morphology, and its development is related to correlated morphology and the relative disposition of the bones and cerebral lobes. Because variation in pneumatization is extensive within the same species, the phyletic implications of pneumatization are limited in the taxa considered here.

El registro más completo de un Hoplophorini (Xenarthra: Glyptodontidae para los Pisos/Edades Chapadmalalense-Marplatense (Plioceno tardío-Pleistoceno temprano The most complete record of a Hoplophorini (Xenarthra: Glyptodontidae for the Chapadmalalan-Marplatan Stages (Late Pliocene-Early Pleistocene

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Alfredo E Zurita

2011-06-01

by Paraglyptodon chapadmalensis (Ameghino in Rovereto, a fossil guide of the Upper Chapadmalalan Stage, and the Plohophorini Plohophorus figuratus Ameghino. On the other hand, the "Hoplophorinae" Hoplophorini are glyptodonts that have its first records during the Huayquerian (late Miocene and "Araucanian" Stages (late Miocene-early Pliocene, but they are almost absents during the Chapadmalalan-Marplatan Stages (Pliocene-early Pleistocene. Later, the Hoplophorini (Neosclerocalyptus Paula Couto are, together with Glyptodon Owen, the most common South American Pleistocene Glyptodontidae. In this contribution we report the first record of a Chapadmalalan Hoplophorini, assigned to the genus Eosclerocalyptus C. Ameghino (Eosclerocalyptus cf. E. lineatus, coming from the Mar del Plata locality, Buenos Aires province (Argentina. This new material, represented by a complete dorsal carapace, was exhumed from the upper section of the Chapadmalalan Formation. From a morphological perspective, this dorsal carapace shows an intermediate size between E. tapinocephalus Cabrera, E. proximus (Moreno & Mercerat and Neosclerocalyptus Paula Couto. Together with cf. Paraglyptodon chapadmalensis and Plohophorus figuratus Ameghino those records represents the most entire Pliocene Glyptodontidae known and, in addition, it partially complete the stratigraphical distribution of the Glyptodontidae Hoplophorini.

A new interdisciplinary approach to the study of the origins of traditional polyphony

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Jordania Joseph

2015-01-01

Full Text Available The article discusses a new model of the origins of choral singing in the context of human evolutionary history. Hominid interaction with predators is seen as a crucial force in the evolution of human morphology and behaviour. Group singing and dancing, with body painting and the use of masks, are perceived as critical elements of the strategy to deter predators and to put hominids into an altered state of consciousness. In this state, humans do not feel fear and pain and are ready to sacrifice their lives for the common goal. This psychological condition is still important to many human group activities, particularly in religion and the military. The mosaic distribution of polyphonic traditions is discussed in the context of the origins of language and articulated speech.

U-Pb ages of detrital zircon from Cenozoic sediments in the southwestern Tarim Basin, NW China: Implications for Eocene-Pliocene source-to-sink relations and new insights into Cretaceous-Paleogene magmatic sources

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Yang, Wei; Fu, Ling; Wu, Chaodong; Song, Yan; Jiang, Zhenxue; Luo, Qun; Zhang, Ziya; Zhang, Chen; Zhu, Bei

2018-05-01

A detailed investigation of potential provenance is still lacking in the southwestern Tarim Basin, which restricts our complete understanding of Cenozoic source-to-sink relations between the basin interior and the Pamir salient - western Kunlun Mountain Range. Debate also exists concerning the potential sources of the Paleogene and Cretaceous igneous detritus present in the Cenozoic sedimentary sequences. Here, we present U-Pb (LA-ICP-MS) ages of detrital zircons from the continuous Eocene-Pliocene sediment series in the well-exposed Aertashi section to investigate changes in sediment provenance through time. The U-Pb detrital zircon ages range widely from 45 to 3204 Ma and can be divided into seven main groups: 45-65 Ma (sub-peak at 49 Ma), 67-103 Ma (sub-peak at 95 Ma), 196-251 Ma (sub-peak at 208 Ma), 252-416 Ma (sub-peak at 296 Ma), 417-540 Ma (sub-peak at 446 Ma), 550-1429 Ma (sub-peaks at 614 Ma, 828 Ma and 942 Ma) and 1345-3204 Ma (sub-peaks at 1773 Ma and 2480 Ma). These zircons were mainly derived from the western Kunlun Mountain Range and northern Pamir salient to the west and south. The evolution of the provenance and source-to-sink relationship patterns in the southwestern Tarim Basin can be divided into three stages: (1) The Middle Eocene to Lower Oligocene sediments display a wide variety of detrital zircon ages, suggesting that the source area was extensive. (2) A major change in provenance occurred during the Late Oligocene to Early Miocene and was characterized by an abrupt increase in the proportion of Triassic and Lower Paleozoic igneous components, implying a significant adjustment in topography induced by the initial uplift and exhumation of the western Kunlun Mountain Range and northern Pamir salient. (3) In the Late Miocene, the source-to-sink system transformed again, and contributions of Triassic to Lower Paleozoic material weakened substantially due to the sufficient indentation of the Pamir salient. Our integrated analyses of zircon

Modeling the stable water isotope expression of El Niño in the Pliocene: Implications for the interpretation of proxy data

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Tindall, Julia C.; Haywood, Alan M.; Thirumalai, Kaustubh

2017-08-01

The El Niño-Southern Oscillation (ENSO) drives interannual climate variability; hence, its behavior over a range of climates needs to be understood. It is therefore important to verify that the paleoarchives, used for preinstrumental ENSO studies, can accurately record ENSO signals. Here we use the isotope enabled Hadley Centre General Circulation Model, HadCM3, to investigate ENSO signals in paleoarchives from a warm paleoclimate, the mid-Pliocene Warm Period (mPWP: 3.3-3.0 Ma). Continuous (e.g., coral) and discrete (e.g., foraminifera) proxy data are simulated throughout the tropical Pacific, and ENSO events suggested by the pseudoproxy data are assessed using modeled ENSO indices. HadCM3 suggests that the ability to reconstruct ENSO from coral data is predominantly dependent on location. However, since modeled ENSO is slightly stronger in the mPWP than the preindustrial, ENSO is slightly easier to detect in mPWP aged coral. HadCM3 also suggests that using statistics from a number of individual foraminifera (individual foraminifera analysis, IFA) generally provides more accurate ENSO information for the mPWP than for the preindustrial, particularly in the western and central Pacific. However, a test case from the eastern Pacific showed that for some locations, the IFA method can work well for the preindustrial but be unreliable for a different climate. The work highlights that sites used for paleo-ENSO analysis should be chosen with extreme care in order to avoid unreliable results. Although a site with good skill for preindustrial ENSO will usually have good skill for assessing mPWP ENSO, this is not always the case.

An-integrated seismic approach to de-risk hydrocarbon accumulation for Pliocene deep marine slope channels, offshore West Nile Delta, Egypt

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Othman, Adel A. A.; Bakr, Ali; Maher, Ali

2017-12-01

The Nile Delta basin is a hydrocarbon rich province that has hydrocarbon accumulations generated from biogenic and thermogenic source rocks and trapped in a clastic channel reservoirs ranging in age from Pliocene to Early Cretaceous. Currently, the offshore Nile Delta is the most active exploration and development province in Egypt. The main challenge of the studied area is that we have only one well in a channel system exceeds fifteen km length, where seismic reservoir characterization is used to de-risk development scenarios for the field by discriminating between gas sand, water sand and shale. Extracting the gas-charged geobody from the seismic data is magnificent input for 3D reservoir static modelling. Seismic data, being non-stationary in nature, have varying frequency content in time. Spectral decomposition analysis unravels the seismic signal into its initial constituent frequencies. Frequency decomposition of a seismic signal aims to characterize the time-dependent frequency response of subsurface rocks and reservoirs for imaging and mapping of bed thickness, geologic discontinuities and channel connectivity. Inversion feasibility study using crossplot between P-wave impedance (Ip) and S-wave impedance (Is) which derived from well logs (P-wave velocity, S-wave velocity and density) is applied to investigate which inversion type would be sufficient enough to discriminate between gas sand, water sand and shale. Integration between spectral analysis, inversion results and Ip vs. Is crossplot cutoffs help to generate 3D lithofacies cubes, which used to extract gas sand and water sand geobodies, which is extremely wonderful for constructing facies depositional static model in area with unknown facies distribution and sand connectivity. Therefore de-risking hydrocarbon accumulation and GIIP estimation for the field became more confident for drilling new development wells.

Cuba - energy management in crisis. Kuba - Energiewirtschaft in der Krise

Energy Technology Data Exchange (ETDEWEB)

Lechuga Vilarino, R. (Hochschule fuer Technik, Wirtschaft und Sozialwesen (HTWS), Zittau/Goerlitz F-H (Germany)); Riesner, W. (Hochschule fuer Technik, Wirtschaft und Sozialwesen (HTWS), Zittau/Goerlitz F-H (Germany))

1994-10-01

In 1993, the drastic decline of the Cuban economy resulted in a partial revelation of socialistic economic principles. A crisis in energy supply brings big parts of agriculture and industry to a standstill caused by a lack of foreign exchange. Collapses in public traffic, daily power cut lasting hours show that the vulnerable spot of the island is exposed with the energy supply. Despite increasing own crude oil extraction (1993: 1.1 mio. t), lack in energy is drastic through dropped subsidies of the former Soviet Union as well as wanting crude oil supplies from this region (decrease of crude oil imports from previously 13 mio. t/a to 13 up to 4 mio. t/a). On the other hand, this critical situation has forced to save energy to better use national owned reserves. It is also planned to continue a nuclear power station concept blocked in 1992. In lack of an own fossil basis of ressources, the utilization of regeneration energy sources is increasingly considered with this bagasse in the centre. Nevertheless it is clear that the gap in energy coverage cannot be managed with this alone. (orig./UA)

A First Look at Oxygen and Silicon Isotope Variations in Diatom Silica from a Pliocene Antarctic Marine Sediment Core

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Abbott, T.; Dodd, J. P.; Hackett, H.; Scherer, R. P.

2016-02-01

Coupled oxygen (δ18O) and silicon (δ30Si) isotope variations in diatom silica (opal-A) are increasingly used as a proxy to reconstruct paleoenvironmental conditions (water temperatures, water mass mixing, nutrient cycling) in marine environments. Diatom silica is a particularly significant paleoenvironmental proxy in high latitude environments, such as the Southern Ocean, where diatom blooms are abundant and diatom frustules are well preserved in the sediment. The Andrill-1B (AND-1B) sediment core from the Ross Sea (Antarctica) preserves several Pliocene ( 4.5 Ma) age diatomite units. Here we present preliminary δ18O and δ30Si values for a diatomite subunit in the AND-1B sediment core. Initial isotope values for the AND-1B diatoms silica record relatively high variability (range δ18O: 36.3‰ to 39.9‰) that could be interpreted as large-scale changes in the water temperature and/or freshwater mixing in the Ross Sea; however, a significant concern with marine sediment of this age is isotope fractionation during diagenesis and the potential formation of opal-CT lepispheres. The effects of clay contamination on the diatom silica δ18O values have been addressed through sample purification and quantified through chemical and physical analyses of the diatom silica. The isotopic effects of opal-CT are not as clearly understood and more difficult to physically separate from the primary diatom silica. In order to better understand the isotope variations in the AND-1B diatoms, we also evaluated silicon and oxygen isotope fractionation during the transition from opal-A to opal-CT in a controlled laboratory experiment. Opal-A from cultured marine diatoms (Thalassiosira weissflogii) was subjected to elevated temperatures (150°C) in acid digestion vessels for 4 weeks to initiate opal-CT precipitation. Quantifying the effects of opal-CT formation on δ18O and δ30Si variations in biogenic silica improves our understanding of the use of diatom silica isotope values a

Stratigraphic record of Pliocene-Pleistocene basin evolution and deformation within the Southern San Andreas Fault Zone, Mecca Hills, California

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McNabb, James C.; Dorsey, Rebecca J.; Housen, Bernard A.; Dimitroff, Cassidy W.; Messé, Graham T.

2017-11-01

A thick section of Pliocene-Pleistocene nonmarine sedimentary rocks exposed in the Mecca Hills, California, provides a record of fault-zone evolution along the Coachella Valley segment of the San Andreas fault (SAF). Geologic mapping, measured sections, detailed sedimentology, and paleomagnetic data document a 3-5 Myr history of deformation and sedimentation in this area. SW-side down offset on the Painted Canyon fault (PCF) starting 3.7 Ma resulted in deposition of the Mecca Conglomerate southwest of the fault. The lower member of the Palm Spring Formation accumulated across the PCF from 3.0 to 2.6 Ma during regional subsidence. SW-side up slip on the PCF and related transpressive deformation from 2.6 to 2.3 Ma created a time-transgressive angular unconformity between the lower and upper members of the Palm Spring Formation. The upper member accumulated in discrete fault-bounded depocenters until initiation of modern deformation, uplift, and basin inversion starting at 0.7 Ma. Some spatially restricted deposits can be attributed to the evolution of fault-zone geometric complexities. However, the deformation events at ca. 2.6 Ma and 0.7 Ma are recorded regionally along 80 km of the SAF through Coachella Valley, covering an area much larger than mapped fault-zone irregularities, and thus require regional explanations. We therefore conclude that late Cenozoic deformation and sedimentation along the SAF in Coachella Valley has been controlled by a combination of regional tectonic drivers and local deformation due to dextral slip through fault-zone complexities. We further propose a kinematic link between the 2.6-2.3 Ma angular unconformity and a previously documented but poorly dated reorganization of plate-boundary faults in the northern Gulf of California at 3.3-2.0 Ma. This analysis highlights the potential for high-precision chronologies in deformed terrestrial deposits to provide improved understanding of local- to regional-scale structural controls on basin

Brief communication: Is variation in the cranial capacity of the Dmanisi sample too high to be from a single species?

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Lee, Sang-Hee

2005-07-01

This study uses data resampling to test the null hypothesis that the degree of variation in the cranial capacity of the Dmanisi hominid sample is within the range variation of a single species. The statistical significance of the variation in the Dmanisi sample is examined using simulated distributions based on comparative samples of modern humans, chimpanzees, and gorillas. Results show that it is unlikely to find the maximum difference observed in the Dmanisi sample in distributions of female-female pairs from comparative single-species samples. Given that two sexes are represented, the difference in the Dmanisi sample is not enough to reject the null hypothesis of a single species. Results of this study suggest no compelling reason to invoke multiple taxa to explain variation in the cranial capacity of the Dmanisi hominids. (c) 2004 Wiley-Liss, Inc

The First Joke: Exploring the Evolutionary Origins of Humor

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Joseph Polimeni

2006-01-01

Full Text Available Humor is a complex cognitive function which often leads to laughter. Contemporary humor theorists have begun to formulate hypotheses outlining the possible innate cognitive structures underlying humor. Humor's conspicuous presence in the behavioral repertoire of humankind invites adaptive explanations. This article explores the possible adaptive features of humor and ponders its evolutionary path through hominid history. Current humor theories and previous evolutionary ideas on humor are reviewed. In addition, scientific fields germane to the evolutionary study of humor are examined: animal models, genetics, children's humor, humor in pathological conditions, neurobiology, humor in traditional societies and cognitive archeology. Candidate selection pressures and associated evolutionary mechanisms are considered. The authors conclude that several evolutionary-related topics such as the origins of language, cognition underlying spiritual feelings, hominid group size, and primate teasing could have special relevance to the origins of humor.

Uranium exploration in Bangladesh

International Nuclear Information System (INIS)

Faruquee, A.R.

1988-01-01

The sedimentary succession of Bangladesh has continental sandstones with lignite and organic matter which are favourable host rocks for sedimentary uranium. The shield areas around Bangladesh are considered good source areas for uranium. Encouraged by this idea, the Bangladesh Atomic Energy Commission (BAEC) started an exploration programme in 1976 with the assistance of the IAEA and the United Nations Development Programme. Preliminary reconnaissance radiometric surveys carried out in 1976-1977 in the Chittagong, Chittagong hill tract and Sylhet districts identified some anomalies with 3 to 5 times the background (XBG). This was followed by regional reconnaissance radiometric surveys which were carried out between 1977 and 1985 in some of the anticlines of the Chittagong and Sylhet districts, including an airborne (helicopter) survey over the Jaldi area. These surveys resulted in the discovery of more than 300 radiometric anomalies of 3 to 60 XBG. They occur in the medium to fine grained ferruginous sandstones of the Dupitila and Tipam Formations of Mio-Pliocene age. These anomalous beds show variation in slime and heavy mineral contents. Some samples collected from the anomalous beds contain uranium and thorium ranging from 20 to 100 ppm and 100 to 1000 ppm, respectively. Exploratory drilling to a depth of about 400 ft was carried out on a very limited scale in the northeastern part of the Sylhet district. Gamma logging of these holes indicated many subsurface anomalies (3 to 21 XBG) in the Dupitila Formation. These anomalies are linked to thin layers with restricted lateral extensions. Geochemical orientation studies and radon surveys were done in some selected areas of Sylhet to test their suitability for further surveys. 9 refs, 13 figs, 4 tabs

Probing atomic scale transformation of fossil dental enamel using Fourier transform infrared and nuclear magnetic resonance spectroscopy: a case study from the Tugen Hills (Rift Gregory, Kenya).

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Yi, Haohao; Balan, Etienne; Gervais, Christel; Ségalen, Loïc; Roche, Damien; Person, Alain; Fayon, Franck; Morin, Guillaume; Babonneau, Florence

2014-09-01

A series of fossil tooth enamel samples was investigated by Fourier transform infrared (FTIR) spectroscopy, (13)C and (19)F magic-angle spinning nuclear magnetic resonance (MAS NMR) and scanning electron microscopy (SEM). Tooth remains were collected in Mio-Pliocene deposits of the Tugen Hills in Kenya. Significant transformations were observed in fossil enamel as a function of increasing fluorine content (up to 2.8wt.%). FTIR spectroscopy revealed a shift of the ν1 PO4 stretching band to higher frequency. The ν2 CO3 vibrational band showed a decrease in the intensity of the primary B-type carbonate signal, which was replaced by a specific band at 864cm(-1). This last band was ascribed to a specific carbonate environment in which the carbonate group is closely associated to a fluoride ion. The occurrence of this carbonate defect was consistently attested by the observation of two different fluoride signals in the (19)F NMR spectra. One main signal, at ∼-100ppm, is related to structural F ions in the apatite channel and the other, at -88ppm, corresponds to the composite defect. These spectroscopic observations can be understood as resulting from the mixture of two phases: biogenic hydroxylapatite (bioapatite) and secondary fluorapatite. SEM observations of the most altered sample confirmed the extensive replacement of the bioapatite by fluorapatite, resulting from the dissolution of the primary bioapatite followed by the precipitation of carbonate-fluorapatite. The ν2 CO3 IR bands can be efficiently used to monitor the extent of this type of bioapatite transformation during fossilization. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Object-based 3D geomodel with multiple constraints for early Pliocene fan delta in the south of Lake Albert Basin, Uganda

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Wei, Xu; Lei, Fang; Xinye, Zhang; Pengfei, Wang; Xiaoli, Yang; Xipu, Yang; Jun, Liu

2017-01-01

The early Pliocene fan delta complex developed in the south of Lake Albert Basin which is located at the northern end of the western branch in the East African Rift System. The stratigraphy of this succession is composed of distributary channels, overbank, mouthbar and lacustrine shales. Limited by the poor seismic quality and few wells, it is full of challenge to delineate the distribution area and patterns of reservoir sands. Sedimentary forward simulation and basin analogue were applied to analyze the spatial distribution of facies configuration and then a conceptual sedimentary model was constructed by combining with core, heavy mineral and palynology evidences. A 3D geological model of a 120 m thick stratigraphic succession was built using well logs and seismic surfaces based on the established sedimentary model. The facies modeling followed a hierarchical object-based approach conditioned to multiple trend constraints like channel intensity, channel azimuth and channel width. Lacustrine shales were modeled as background facies and then in turn eroded by distribute channels, overbank and mouthbar respectively. At the same time a body facies parameter was created to indicate the connectivity of the reservoir sands. The resultant 3D facies distributions showed that the distributary channels flowed from east bounding fault to west flank and overbank was adhered to the fringe of channels while mouthbar located at the end of channels. Furthermore, porosity and permeability were modeled using sequential Gaussian simulation (SGS) honoring core observations and petrophysical interpretation results. Despite the poor seismic is not supported to give enough information for fan delta sand distribution, creating a truly representative 3D geomodel is still able to be achieved. This paper highlights the integration of various data and comprehensive steps of building a consistent representative 3D geocellular fan delta model used for numeral simulation studies and field

Development of CO{sub 2} emissions in Germany in 2016. However, an approach to the target for 2020 again fails to appear; Entwicklung der CO{sub 2}-Emissionen in Deutschland im Jahr 2016. Annaeherung an das Ziel fuer 2020 bleibt abermals aus

Energy Technology Data Exchange (ETDEWEB)

Ziesing, Hans-Joachim

2017-06-15

In 2016, the total CO{sub 2} emissions in Germany again rose slightly. Compared to the previous year, they were about 0.5% (4.2 million tonnes) higher than in the previous year. Temperature-adjusted, however, the emissions remained practical unchanged. Emissions of all greenhouse gases are likely to have risen by around 0.4% (just under 4 million tonnes) in 2016 or have remained almost constant at the previous year's level. Independent of the assessment of the changes in the values of origin or the temperature-adjusted values, the 2016 target route was clearly missed. To this end, the unadjusted greenhouse gas emissions would have to fall by around 3,6% or around 30 million tonnes in 2016. In order to achieve the 40% reduction target by 2020, emissions must be reduced by almost 39 million t CO{sub 2} equivalents every year over the four years from 2017 to 2020. Significant climate protection policy needs are evident. [German] Im Jahr 2016 sind die gesamten CO{sub 2}-Emissionen in Deutschland erneut leicht gestiegen. Gegenueber dem Vorjahr waren sie um etwa 0,5 % (4,2 Mio. t) hoeher als im Vorjahr. Temperaturbereinigt blieben die Emissionen allerdings praktisch unveraendert. Die Emissionen aller Treibhausgase duerften 2016 um rund 0,4% (knapp 4 Mio. t) zugenommen bzw. temperaturbereinigt fast auf dem Vorjahresniveau verharrt haben. Unabhaengig von der Einschaetzung nach den Veraenderungen der Ursprungswerte oder der temperaturbereinigten Werte ist auch 2016 der bis 2020 angestrebte Zielpfad deutlich verfehlt worden. Dazu haetten die unbereinigten Treibhausgasemissionen im Jahr 2016 um rund 3,6 % oder um etwa 30 Mio. t sinken muessen. Um das Reduktionsziel von 40 % bis 2020 noch zu erreichen, muessen die Emissionen in den 4 Jahren von 2017 bis 2020 jedes Jahr um nahezu 39 Mio. t CO{sub 2}-Aequivalente gesenkt werden. Ein erheblicher klimaschutzpolitischer Handlungsbedarf ist evident.

Enhancement of absorption and resistance of motion utilizing a multi-channel opto-electronic sensor to effectively monitor physiological signs during sport exercise

Science.gov (United States)

Alzahrani, Abdullah; Hu, Sijung; Azorin-Peris, Vicente; Barrett, Laura; Esliger, Dale; Hayes, Matthew; Akbare, Shafique; Achart, Jérôme; Kuoch, Sylvain

2015-03-01

This study presents an effective engineering approach for human vital signs monitoring as increasingly demanded by personal healthcare. The aim of this work is to study how to capture critical physiological parameters efficiently through a well-constructed electronic system and a robust multi-channel opto-electronic patch sensor (OEPS), together with a wireless communication. A unique design comprising multi-wavelength illumination sources and a rapid response photo sensor with a 3-axis accelerometer enables to recover pulsatile features, compensate motion and increase signal-to-noise ratio. An approved protocol with designated tests was implemented at Loughborough University a UK leader in sport and exercise assessment. The results of sport physiological effects were extracted from the datasets of physical movements, i.e. sitting, standing, waking, running and cycling. t-test, Bland-Altman and correlation analysis were applied to evaluate the performance of the OEPS system against Acti-Graph and Mio-Alpha.There was no difference in heart rate measured using OEPS and both Acti-Graph and Mio-Alpha (both p<0.05). Strong correlations were observed between HR measured from the OEPS and both the Acti-graph and Mio-Alpha (r = 0.96, p<0.001). Bland-Altman analysis for the Acti-Graph and OEPS found the bias 0.85 bpm, the standard deviation 9.20 bpm, and the limits of agreement (LOA) -17.18 bpm to +18.88 bpm for lower and upper limits of agreement respectively, for the Mio-Alpha and OEPS the bias is 1.63 bpm, standard deviation SD8.62 bpm, lower and upper limits of agreement, - 15.27 bpm and +18.58 bpm respectively. The OEPS demonstrates a real time, robust and remote monitoring of cardiovascular function.

Estudo clínico da aplicação de matriz inorgânica de osso associado a peptídeo sintético de adesão celular (MIO/P-15, PepGen P-15®, em lesões periodontais avançadas de cães Clinical study of effectiveness of an anorganic bone matrix and cell-binding peptide (ABM/P-15, PepGen-P15®: application in advanced periodontal lesions of dogs

Directory of Open Access Journals (Sweden)

Daniel G. Ferro

2009-02-01

Full Text Available Os mecanismos biológicos desenvolvidos para aumentar a qualidade da regeneração óssea e da reparação tecidual de sítios periodontais específicos continuam a ser um desafio e têm sido complementado pela capacidade de adesão celular do colágeno do tipo I, promovida por um peptídeo sintético de adesão celular (P-15, associado a uma matriz inorgânica de osso (MIO para formar MIO/P-15. O objetivo deste estudo foi avaliar a perda do nível clínico de inserção e a resposta da bolsa periodontal em dentes após 3 e 6 meses da aplicação de enxerto com MIO/P-15. Vinte e um cães do Hospital Veterinário da Universidade de São Paulo foram anestesiados para realização de tratamento periodontal e 132 faces dentais com perda de nível clínico de inserção foram tratadas, sendo que 36,4% (48 faces receberam o peptídeo de adesão celular e 63,6% (84 faces compuseram o grupo controle que recebeu tratamento convencional (retalho muco-gengival e aplainamento radicular. O procedimento foi documentado através de radiografia intra-oral e todas as sondagens de bolsas periodontais foram fotografadas. Depois de 3 e de 6 meses, os animais foram re-anestesiados a fim de se obter novas avaliações, radiografias, fotografias e sondagens periodontais. As 48 faces com perda de nível clínico de inserção que receberam material de enxertia apresentaram taxa de 40% de recuperação do nível clínico de inserção após 6 meses. O grupo controle de faces dentais não apresentou alteração do nível clínico de inserção. A face palatina foi a que apresentou melhor taxa de regeneração (40% e os dentes caninos e molares mostraram as melhores respostas (57,14% e 65%, respectivamente. Não houve sinais de infecção pós-cirúrgica relacionadas à falta de higienização oral dos animais. Pode-se concluir que o MIO/P-15 auxilia na regeneração e re-aderência das estruturas periodontais, incluindo osso alveolar. Sua aplicação mostrou-se fácil e

Sedimentology and paleoenvironments of a new fossiliferous late Miocene-Pliocene sedimentary succession in the Rukwa Rift Basin, Tanzania

Science.gov (United States)

Mtelela, Cassy; Roberts, Eric M.; Hilbert-Wolf, Hannah L.; Downie, Robert; Hendrix, Marc S.; O'Connor, Patrick M.; Stevens, Nancy J.

2017-05-01

This paper presents a detailed sedimentologic investigation of a newly identified, fossiliferous Late Neogene sedimentary succession in the Rukwa Rift Basin, southwestern Tanzania. This synrift deposit is a rare and significant new example of a fossiliferous succession of this age in the Western Branch of East Africa Rift System. The unit, informally termed the lower Lake Beds succession, is late Miocene to Pliocene in age based on cross-cutting relationships, preliminary biostratigraphy, and U-Pb geochronology. An angular unconformity separates the lower Lake Beds from underlying Cretaceous and Oligocene strata. Deposition was controlled by rapid generation of accommodation space and increased sediment supply associated with late Cenozoic tectonic reactivation of the Rukwa Rift and synchronous initiation of the Rungwe Volcanic Centre. The lower Lake Beds, which have thus far only been identified in three localities throughout the Rukwa Rift Basin, are characterized by two discrete lithologic members (herein A and B). The lower Member A is a volcanic-rich succession composed mostly of devitrified volcanic tuffs, and volcaniclastic mudstones and sandstones with minor conglomerates. The upper Member B is a siliciclastic-dominated succession of conglomerates, sandstones, mudstones and minor volcanic tuffs. Detailed facies analysis of the lower Lake Beds reveals various distinctive depositional environments that can be grouped into three categories: 1) alluvial fan; 2) fluvial channel; and 3) flood basin environments, characterized by volcanoclastic-filled lakes and ponds, abandoned channel-fills and pedogenically modified floodplains. Member A represents a shallow lacustrine setting filled by tuffaceous sediments, which grade up into a system of alluvial fans and high-energy, proximal gravel-bed braided rivers. An unconformity marks the contact between the two members. Member B shows an upward transition from a high-energy, gravel-bed braided river system to a sandy

Visible Korean human images on MIOS system

Science.gov (United States)

Har, Donghwan; Son, Young-Ho; Lee, Sung-Won; Lee, Jung Beom

2004-05-01

Basically, photography has the attributes of reason, which encompasses the scientific knowledge of optics, physics and chemistry, and delicate sensibility of individuals. Ultimately, the photograph pursues "effective communication." Communication is "mental and psychosocial exchange mediated by material symbols, such as language, gesture and picture," and it has four compositions: "sender, receiver, message and channel." Recently, a change in the communication method is on the rise in the field of art and culture, including photography. Until now, communication was mainly achieved by the form of messages unilaterally transferred from senders to receivers. But, nowadays, an interactive method, in which the boundary of sender and receiver is obscure, is on the increase. Such new communication method may be said to have arrived from the desire of art and culture societies, pursuing something new and creative in the background of utilization of a variety of information media. The multi-view screen we developed is also a communication tool capable of effective interaction using photos or motion pictures. The viewer can see different images at different locations. It utilizes the basic lenticular characteristics, which have been used in printing. Each motion picture is displayed on the screen without crosstalk. The multi-view screen is different in many aspects from other display media, and is expected to be utilized in many fields, including advertisement, display and education.

Land substitution effects of biofuel side products and implications on the land area requirement for EU 2020 biofuel targets

International Nuclear Information System (INIS)

Ozdemir, Enver Doruk; Haerdtlein, Marlies; Eltrop, Ludger

2009-01-01

The provision of biofuels today is based on energy crops rather than residual biomass, which results in the requirement of agricultural land area. The side products may serve as animal feed and thus prevent cultivation of other feedstock and the use of corresponding land area. These effects of biofuel provision have to be taken into account for a comprising assessment of land area requirement for biofuel provision. Between 18.5 and 21.1 Mio. hectares (ha) of land area is needed to meet the EU 2020 biofuel target depending on the biofuel portfolio when substitution effects are neglected. The utilization of the bioethanol side products distiller's dried grain and solubles (DDGS) and pressed beet slices may save up to 0.7 Mio. ha of maize cultivation area in the EU. The substitution effect due to the utilization of biodiesel side products (oil cakes of rape, palm and soy) as animal feed may account for up to 7.1 Mio. ha of soy cultivation area in Brazil. The results show that the substitution of land area due to use of side products might ease the pressures on land area requirement considerably and should therefore not be neglected in assessing the impacts of biofuel provision worldwide.

STUDY OF THE EFFECT OF ENDFACES POLISHING ANGLE FOR ANISOTROPIC WAVEGUIDES ON STATE CONVERSION OF LIGHT POLARIZATION

Directory of Open Access Journals (Sweden)

V. A. Shulepov

2016-05-01

Full Text Available The paper deals with optical scheme for research of polarization state transformation at the junction of anisotropic waveguides. It consists of a light source, polarization controller, multifunctional integrated optical scheme (MIOS, single-mode fiber for input and output of optical radiation in MIOS and the polarization scanning Michelson interferometer. Optical radiation from the source of the plant comes through the polarization controller in one of the MIOS ports. Further, in one of the opposite ports the radiation is received by different fibers, polished at the angles of 19.5˚, 10.5˚ and 0˚. After that, the optical radiation gets into polarization Michelson interferometer. With that, the picture visibility is analyzed at different displacement of one arm upon which the value has been determined in the polarization conversion point connections. At the course of work it was obtained that the polarization state conversion at a splicing point rises with the slant angle deviation from its optimal value. Anisotropic waveguides splicing is one of the main tasks during fabrication of any fiber-optic sensor with integrated optical elements. The results of this work are of great interest for the wide range of specialists in the optical waveguides application field.

Tüdimus ; Levant ; Agoonia ; Varjutus ; Mälestuseks ; Jõed ; Jõulud ; Kui sina mu vend ; Faas ; Maetud sadam ; Õhtul ; Needus ; Juuni ; Magada ; Rahu : [luuletused] / Giuseppe Ungaretti ; tõlk. Malle Talvet ja Auli Ott

Index Scriptorium Estoniae

Ungaretti, Giuseppe

2003-01-01

Andmed autori kohta lk. 28. Orig.: Noia ; Levante ; Agonia ; Chiaroscuro ; In memoria ; I fiumi ; Natale ; Se tu mio fratello ; Fase ; Il porto sepolto ; Stasera ; Dannazione ; Giugno ; Dormire ; Quiete

Biometrical studies upon hominoid teeth: the coefficient of variation, sexual dimorphism and questions of phylogenetic relationship.

Science.gov (United States)

Blumenberg, B

1985-01-01

Sexual dimorphism as a function of variation in hominoid tooth metrics has been investigated for four groups of taxa: Recent great apes (two subfamilies), Dryopiths (one subfamily), Ramapiths (one subfamily) and hominids (one family). Gorilla, and to a lesser extent Pan, appear characterized by very high levels of sexual dimorphism and meet several criteria for statistical outliers. Recent great apes are the only group exhibiting consistently high levels of sexual dimorphism. Ramapiths are the only group characterized by low levels of sexual dimorphism and their relative canine length is most similar to Dryopiths. Both Dryopiths and hominids contain taxa with low and intermediate levels of sexual dimorphism. The Gingerich and Shoeninger hypothesis relating coefficients of variation to occlusal complexity is supported. Non-parametric statistics suggest that homogeneity of coefficient of variation profiles over most of the tooth row is characteristic of only the Dryopiths and a composite data set composed of the Dryopith plus Ramapith tooth measurements. Oxnard's model for the multifactorial basis of multiple sexual dimorphisms is also supported. The Dryopith and hominid patterns of sexual dimorphism are similar, an observation that suggests phylogenetic relationship. At the taxonomic level of subfamily or family, sexual dimorphism is a character of cladistic usefulness and possible phylogenetic valence. Assuming that breeding system and sexual dimorphism are functional correlates as many workers suggest, then Ramapithecus sp. China, Sivapithecus indicus and possibly Australopithecus boisei are good candidates for having possessed monogamous breeding/social structures. All Dryopith taxa, S. sivalensis, Sivapithecus sp. China, A. afarensis, Homo habilis and H. erectus emerge as the best candidates for having possessed a polygynous breeding/social structure. No biometrical affinities of Ramapiths with hominids can be demonstrated and some phylogenetic relationship with

Trace-element and Sr, Nd, Pb, and O isotopic composition of Pliocene and Quaternary alkali basalts of the Patagonian Plateau lavas of southernmost South America

Science.gov (United States)

Stern, C.R.; Frey, F.A.; Futa, K.; Zartman, R.E.; Peng, Z.; Kurtis, Kyser T.

1990-01-01

The Pliocene and Quaternary Patagonian alkali basalts of southernmost South America can be divided into two groups. The "cratonic" basalts erupted in areas of Cenozoic plateau volcanism and continental sedimentation and show considerable variation in 87Sr/86Sr (0.70316 to 0.70512), 143Nd/144Nd (e{open}Nd) and 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios (18.26 to 19.38, 15.53 to 15.68, and 38.30 to 39.23, respectively). These isotopic values are within the range of oceanic island basalts, as are the Ba/La, Ba/Nb, La/Nb, K/Rb, and Cs/Rb ratios of the "cratonic" basalts. In contrast, the "transitional" basalts, erupted along the western edge of the outcrop belt of the Pliocene and Quaternary plateau lavas in areas that were the locus of earlier Cenozoic Andean orogenic arc colcanism, have a much more restricted range of isotopic composition which can be approximated by 87Sr/86Sr=0.7039??0.0004, e{open}Nd, 206Pb/204Pb=18.60??0.08, 207Pb/204Pb=15.60??0.01, and 208Pb/204Pb=38.50??0.10. These isotopic values are similar to those of Andean orogenic are basalts and, compared to the "cratonic" basalts, are displaced to higher 87Sr/86Sr at a given 143Nd/144Nd and to higher 207Pb/204Pb at a given 208Pb/204Pb. The "transitional" basalts also have Ba/La, Ba/Nb, La/Nb, and Cs/Rb ratios higher than the "cratonic" and oceanic island basalts, although not as high as Andean orogenic are basalts. In contrast to the radiogenic isotopes, ??18O values for both groups of the Patagonian alkali basalts are indistinguishable and are more restricted than the range reported for Andean orogenic are basalts. Whole rock ??18O values calculated from mineral separates for both groups range from 5.3 to 6.5, while measured whole rock ??18O values range from 5.1 to 7.8. The trace element and isotopic data suggest that decreasing degrees of partial melting in association with lessened significance of subducted slabderived components are fundamental factors in the west to east transition from arc

Volcanic history and petrography of the Pliocene Etrüsk Stratovolcano, E Turkey

Science.gov (United States)

Oyan, Vural; Keskin, Mehmet; Lebedev, Vladimir; Sharkov, Evgenii; Lustrino, Michele; Mattioli, Michele

2010-05-01

The Pliocene Etrusk volcano, with its 3100 m elevation and ~500 km2 area, is one of the major centers of the collision-related volcanism in E Anatolia. It is located in the northeast of Lake Van, sitting almost on the culmination of the "Lake Van dome" structure forming the vertex of the eastern Turkish high plateau (Sengor et al., 2008). A ~5-km-wide horseshoe-shaped caldera, open to the south, is located in the center of the volcano. Apart from two trace element analyses and two K/Ar dates, there are virtually no data available in the literature on this major eruption center. Our study intends to fill this gap with a detailed petrographical, geochemical and geochronological study. Our new K/Ar age determinations indicate that the main volcanic edifice of the Etrusk volcano was formed in period between 4.3 and 3.9 Ma, with the eruption of several intermediate to acid lavas from a central vent. This phase ended up with the formation of a small collapse caldera that produced pyroclastic material emplaced on the earlier lavas. The final impulse of the volcano activity from the Etrusk volcanic center was the eruption of a post-caldera rhyolitic lava flow from the southern flank of the volcano (~3.8-3.7 Ma). After about 2.7 Myr of magmatic quiescence, during the Quaternary time between ~1 and 0.43 Ma, basalts erupted from the SW flank of the Etrusk volcano. They were generated predominantly from a ~N-S extending fissure, as well as from a scoria cone (Karniyarik hill) and a maar-shaped volcanic center (i.e. Düzgeyikçukuru). Edifice-forming products of the Etrüsk stratovolcano are represented by sanidine-plagioclase-biotite-clinopyroxene-phyric trachytes and plagioclase-clinopyroxene-orthopyroxene-phyric trachyandesites containing sporadic olivine phenocrysts. K-feldspar is the most abundant mineral phase in trachitic lavas of the Etrüsk volcanic system. Post caldera lavas, on the other hand, have relatively more evolved compositions ranging from trachydacite to

The temporal bones from Sima de los Huesos Middle Pleistocene site (Sierra de Atapuerca, Spain). A phylogenetic approach.

Science.gov (United States)

Martínez, I; Arsuaga, J L

1997-01-01

Three well-preserved crania and 22 temporal bones were recovered from the Sima de los Huesos Middle Pleistocene site up to and including the 1994 field season. This is the largest sample of hominid temporal bones known from a single Middle Pleistocene site and it offers the chance to characterize the temporal bone morphology of an European Middle Pleistocene population and to study the phylogenetic relationships of the SH sample with other Upper and Middle Pleistocene hominids. We have carried out a cladistic analysis based on nine traits commonly used in phylogenetic analysis of Middle and Late Pleistocene hominids: shape of the temporal squama superior border, articular eminence morphology, contribution of the sphenoid bone to the median glenoid wall, postglenoid process projection, tympanic plate orientation, presence of the styloid process, mastoid process projection, digastric groove morphology and anterior mastoid tubercle. We have found two autapomorphies on the Home erectus temporal bone: strong reduction of the postglenoid process and absence of the styloid process. Modern humans, Neandertals and the Middle Pleistocene fossils from Europe and Africa constitute a clade characterized by a convex superior border of the temporal squama. The European Middle Pleistocene fossils from Sima de los Huesos, Petralona, Steinheim, Bilzingsleben and Castel di Guido share a Neandertal apomorphy: a relatively flat articular eminence. The fossils from Ehringsdorf, La Chaise Suardi and Biache-Saint-Vaast also display another Neandertal derived trait: an anteriorly obliterated digastric groove. Modern humans and the African Middle Pleistocene fossils share a synapomorphy: a sagittally orientated tympanic plate.

Beyond the Pleistocene: Using Phylogeny and Constraint to Inform the Evolutionary Psychology of Human Mating

Science.gov (United States)

Eastwick, Paul W.

2009-01-01

Evolutionary psychologists explore the adaptive function of traits and behaviors that characterize modern Homo sapiens. However, evolutionary psychologists have yet to incorporate the phylogenetic relationship between modern Homo sapiens and humans' hominid and pongid relatives (both living and extinct) into their theorizing. By considering the…

Louis Leakey and Mary Leakey

Indian Academy of Sciences (India)

Permanent link: https://www.ias.ac.in/article/fulltext/reso/020/08/0667-0679. Keywords. Palaeoanthropology; human evolution; Louis Leakey; Mary Leakey; Africa; Olduvai gorge; fossil hominids. Author Affiliations. Rajan Gaur1. Department of Anthropology, Panjab University, Sector 14, Chandigarh UT 160 014, India ...

Late Pliocene - Early Pleistocene paleoenvironmental reconstruction based on stable isotope compositions of Stephanorhinus sp. and Mammut sp. teeth

Science.gov (United States)

Szabó, Péter; Kovács, János; Kocsis, László; Gasparik, Mihály; Vennemann, Torsten; Demény, Attila; Virág, Attila

2014-05-01

Stable isotope measurements of skeletal apatite from herbivorous mammals are often used to provide information on the terrestrial paleoenvironment and paleoclimate. In this study fossil teeth of Stephanorhinus Kretzoi 1942 (rhinoceros) and Mammut Blumenbach 1799 (mastodon), amongst others, were investigated from the Carpathian Basin. According to the biostratigraphy, the age of the samples has a range from Late Pliocene to Early Pleistocene. Reconstructing paleoclimate and paleoenvironment of this era is important as it can be an analogue for the future climate. Oxygen and carbon isotopic compositions were measured from the tooth enamel, because it is believed to be the most resistant to diagenetic alteration (e.g., Kohn & Cerling, 2002). The carbon isotopic composition in the carbonate fraction of apatite can be related to the diet of the animal (Kohn & Cerling, 2002). Hence, it can reflect the photosynthetic pathway (C3 or C4) of the plants consumed by these herbivores. The δ18O values were determined in the phosphate fraction of apatite. In the case of large mammals that are obligate drinkers, the δ18O values closely track those of the environmental water (Bryant & Froelich, 1995). Knowing the δ18O values of environmental water and relating it to local precipitation, the mean annual temperature (MAT) of the site can be calculated (Dansgaard, 1964). The δ13C values range from -10 to -15 o (VPDB). The result clearly shows that these animals consumed C3 plants. Most of the δ13C values indicate mixed grassland-open woodland rather than a closed canopy forest. Although there is variation in the δ18O values (mean 14.2 ± 1.0 o VSMOW, n=17), most of the samples would support a MAT range of 8-12 ° C. This is in good agreement with other proxies for the localities and time period (Kovács et al., 2013). Bryant, D.J. & Froelich, P.N. (1995) A model of oxygen-isotope fractionation in bodywater of large-mammals. Geochimica et Cosmochimica Acta 59, 4523

The costs of power interruptions in Germany. An assessment in the light of the Energiewende

Energy Technology Data Exchange (ETDEWEB)

Growitsch, Christian; Malischek, Raimund; Nick, Sebastian; Wetzel, Heike

2013-04-15

The German Energiewende's potential effects on the reliability of electricity supply as well as the corresponding economic consequences have recently entered both the political and scientific debate. However, empirical evidence of power outage costs in Germany is rather scarce. Following a macroeconomic approach, we analyse the economic costs imposed by potential power interruptions in Germany. Investigating a rich data set on industry and households we estimate both Values of Lost Load (VoLLs) and associated costs of power interruptions for different German regions and sectors and every hour of the year. This disaggregated approach allows for conclusions for optimal load shedding in case of technical necessity and the economic efficiency of measures to improve security of supply. We find that interruption costs vary significantly over time, between sectors and regions. Peaking on midday of a Monday in December at 750 Mio Euro per hour, the average of total national outage costs amount to approximately 430 Mio Euro per hour. The industrial sectors facing the highest outage costs are the machinery and transport equipment sectors. Their aggregated hourly outage costs average out at approximately 20 Mio Euro. Our results emphasize the prominent regional aspect of the German Energiewende as the regions with the highest estimated cost of interruptions in South and West Germany coincide with the areas which face nuclear power plant shut downs in the near future.

A Multi-Channel Opto-Electronic Sensor to Accurately Monitor Heart Rate against Motion Artefact during Exercise

Directory of Open Access Journals (Sweden)

Abdullah Alzahrani

2015-10-01

Full Text Available This study presents the use of a multi-channel opto-electronic sensor (OEPS to effectively monitor critical physiological parameters whilst preventing motion artefact as increasingly demanded by personal healthcare. The aim of this work was to study how to capture the heart rate (HR efficiently through a well-constructed OEPS and a 3-axis accelerometer with wireless communication. A protocol was designed to incorporate sitting, standing, walking, running and cycling. The datasets collected from these activities were processed to elaborate sport physiological effects. t-test, Bland-Altman Agreement (BAA, and correlation to evaluate the performance of the OEPS were used against Polar and Mio-Alpha HR monitors. No differences in the HR were found between OEPS, and either Polar or Mio-Alpha (both p > 0.05; a strong correlation was found between Polar and OEPS (r: 0.96, p < 0.001; the bias of BAA 0.85 bpm, the standard deviation (SD 9.20 bpm, and the limits of agreement (LOA from −17.18 bpm to +18.88 bpm. For the Mio-Alpha and OEPS, a strong correlation was found (r: 0.96, p < 0.001; the bias of BAA 1.63 bpm, SD 8.62 bpm, LOA from −15.27 bpm to +18.58 bpm. These results demonstrate the OEPS to be capable of carrying out real time and remote monitoring of heart rate.

Denisovans, Melanesians, Europeans, and Neandertals: The Confusion of DNA Assumptions and the Biological Species Concept.

Science.gov (United States)

Caldararo, Niccolo

2016-08-01

A number of recent articles have appeared on the Denisova fossil remains and attempts to produce DNA sequences from them. One of these recently appeared in Science by Vernot et al. (Science 352:235-239, 2016). We would like to advance an alternative interpretation of the data presented. One concerns the problem of contamination/degradation of the determined DNA sequenced. Just as the publication of the first Neandertal sequence included an interpretation that argued that Neandertals had not contributed any genes to modern humans, the Denisovan interpretation has considerable influence on ideas regarding human evolution. The new papers, however, confuse established ideas concerning the nature of species, as well as the use of terms like premodern, Archaic Homo, and Homo heidelbergensis. Examination of these problems presents a solution by means of reinterpreting the results. Given the claims for gene transfer among a number of Mid Pleistocene hominids, it may be time to reexamine the idea of anagenesis in hominid evolution.

Tempo and mode in human evolution.

Science.gov (United States)

McHenry, H M

1994-01-01

The quickening pace of paleontological discovery is matched by rapid developments in geochronology. These new data show that the pattern of morphological change in the hominid lineage was mosaic. Adaptations essential to bipedalism appeared early, but some locomotor features changed much later. Relative to the highly derived postcrania of the earliest hominids, the craniodental complex was quite primitive (i.e., like the reconstructed last common ancestor with the African great apes). The pattern of craniodental change among successively younger species of Hominidae implies extensive parallel evolution between at least two lineages in features related to mastication. Relative brain size increased slightly among successively younger species of Australopithecus, expanded significantly with the appearance of Homo, but within early Homo remained at about half the size of Homo sapiens for almost a million years. Many apparent trends in human evolution may actually be due to the accumulation of relatively rapid shifts in successive species. PMID:8041697

Development and progress: advancing towards environmental crisis

International Nuclear Information System (INIS)

Gomez G, Luis Jair

2011-01-01

Physical, biological and social evolution is doubtless. One of its first manifestations is the arrival of technique when hominids emerge from pre-hominids. Those first technical developments implied a new relation man/environment that was expressed in three components that appeared successively and pushed each other in time and space like this: dominion over nature, population concentration (urbanism), and population growth. Techniques are to generate three notorious effects on the relation man/nature: 1. Deep intervention on the physical environment: mining and industrial transformation processes; 2. Deep intervention on the biological environment: development of agriculture with a decrease in biodiversity; and 3. Deep intervention on the social environment: going from a pre-modern communitarian world, to the individualism of modernity; and from the agrarian field to the big city. All these technical developments boosted dominion of the technosphere over the ecosphere, which led to the appearance of the Environmental Crisis, whose most notable manifestation is Climatic Change.

The relative cost of bent-hip bent-knee walking is reduced in water.

Science.gov (United States)

Kuliukas, Algis V; Milne, Nick; Fournier, Paul

2009-01-01

The debate about how early hominids walked may be characterised as two competing hypotheses: They moved with a fully upright (FU) gait, like modern humans, or with a bent-hip, bent-knee (BK) gait, like apes. Both have assumed that this bipedalism was almost exclusively on land, in trees or a combination of the two. Recent findings favoured the FU hypothesis by showing that the BK gait is 50-60% more energetically costly than a FU human gait on land. We confirm these findings but show that in water this cost differential is markedly reduced, especially in deeper water, at slower speeds and with greater knee flexion. These data suggest that the controversy about australopithecine locomotion may be eased if it is assumed that wading was a component of their locomotor repertoire and supports the idea that shallow water might have been an environment favourable to the evolution of early forms of "non-optimal" hominid bipedalism.

Aural exostoses (surfer's ear) provide vital fossil evidence of an aquatic phase in Man's early evolution.

Science.gov (United States)

Rhys Evans, P H; Cameron, M

2017-11-01

For over a century, otolaryngologists have recognised the condition of aural exostoses, but their significance and aetiology remains obscure, although they tend to be associated with frequent swimming and cold water immersion of the auditory canal. The fact that this condition is usually bilateral is predictable since both ears are immersed in water. However, why do exostoses only grow in swimmers and why do they grow in the deep bony meatus at two or three constant sites? Furthermore, from an evolutionary point of view, what is or was the purpose and function of these rather incongruous protrusions? In recent decades, paleoanthropological evidence has challenged ideas about early hominid evolution. In 1992 the senior author suggested that aural exostoses were evolved in early hominid Man for protection of the delicate tympanic membrane during swimming and diving by narrowing the ear canal in a similar fashion to other semiaquatic species. We now provide evidence for this theory and propose an aetiological explanation for the formation of exostoses.

Brains, tools, innovation and biogeography in crows and ravens

DEFF Research Database (Denmark)

Jønsson, Knud Andreas; Fabre, Pierre-Henri Fréderic; Irestedt, Martin

2012-01-01

BACKGROUND:Crows and ravens (Passeriformes: Corvus) are large-brained birds with enhanced cognitive abilities relative to other birds. They are among the few non-hominid organisms on Earth to be considered intelligent and well-known examples exist of several crow species having evolved innovative....... Hence, we propose that all crows and ravens have relatively large brains compared to other birds and thus the potential to be innovative if conditions and circumstances are right.......BACKGROUND:Crows and ravens (Passeriformes: Corvus) are large-brained birds with enhanced cognitive abilities relative to other birds. They are among the few non-hominid organisms on Earth to be considered intelligent and well-known examples exist of several crow species having evolved innovative...... Corvus. We date the phylogeny and determine ancestral areas to investigate historical biogeographical patterns of the crows. Additionally, we use data on brain size and a large database on innovative behaviour and tool use to test whether brain size (i) explains innovative behaviour and success...

THE BAIKAL RIFT: PLIOCENE (MIOCENE – QUATERNARY EPISODE OR PRODUCT OF EXTENDED DEVELOPMENT SINCE THE LATE CRETACEOUS UNDER VARIOUS TECTONIC FACTORS. A REVIEW

Directory of Open Access Journals (Sweden)

V. D. Mats

2015-01-01

Full Text Available The article reviews three typical concepts concerning the age of the Baikal rift (BR which development is still underway: 5 Ma (the BR development start in the Late Pliocene, 30 Ma (Miocene or Oligocene, and 60–70 Ma (the Late Cretaceous. Under the concept of the young BR age (Pliocene–Quaternary [Artyushkov, 1993; Nikolaev et al., 1985; Buslov, 2012], according to E.V. Artyushkov, BR is not a rift, but a graben due to the fact that the pre‐Pliocene structure of BR does not contain any elements that would be indicative of tensile stresses. However, field studies reported in [Lamakin, 1968; Ufimtsev, 1993; Zonenshain et al., 1995; Mats, 1993, 2012; Mats et al., 2001] have revealed that extension structures, such as tilted blocks and listric faults, are abundant in the Baikal basin (BB, and thus do not supportE.V. Artyushkov’s argumentation. The opinion that BR is young is shared by M.M. Buslov [2012]; he refers to studies of  Central Asia and states that only the Pliocene‐Quaternary structure of BB is a rift, while the oldest Cenozoic structures (Upper Cretaceous – Miocene are just fragments of the large Cenozoic Predbaikalsky submontane trough (PBT which are not related to the rift. However, the coeval Cenozoic lithological compositions, thicknesses of sediment layers and types of tectonic structures in PBT and BB have nothing in common. Across the area separating PBT and BB, there are no sediments or structures to justify a concept that BR and PBT may be viewed as composing a single region with uniform structures and formations. The idea of the Pliocene‐Quaternary age of BR should be rejected as it contradicts with the latest geological and geophysical data. Seismic profiling in BB has revealed the syn‐rift sedimentary bed which thickness exceeds 7.5 km. Results of drilling through the 600‐metre sedimentary sequence of Lake Baikal suggest the age of 8.4 Ma [Horiuchi et al., 2004], but M.M. Buslov believes

Quantum Field Theory in Curved Spacetime

Science.gov (United States)

Reynolds, Sally C.; Gallagher, Andrew

2012-03-01

List of contributors; Foreword J. T. Francis Thackeray; 1. African genesis: an evolving paradigm Sally C. Reynolds; 2. Academic genealogy Peter Ungar and Phillip V. Tobias; Part I. In Search of Origins: Evolutionary Theory, New Species, and Paths into the Past: 3. Speciation in hominin evolution Colin Groves; 4. Searching for a new paradigm for hominid origins in Chad (Central Africa) Michel Brunet; 5. From hominoid arboreality to hominid bipedalism Brigitte Senut; 6. Orrorin and the African ape/hominid dichotomy Martin Pickford; 7. A brief history and results of 40 years of Sterkfontein excavations Ronald J. Clarke; Part II. Hominin Morphology Through Time: Brains, Bodies and Teeth: 8. Hominin brain evolution, 1925-2011: an emerging overview Dean Falk; 9. The issue of brain reorganisation in Australopithecus and early hominids: Dart had it right Ralph L. Holloway; 10. The mass of the human brain: is it a spandrel? Paul R. Manger, Jason Hemingway, Muhammad Spocter and Andrew Gallagher; 11. Origin and diversity of early hominin bipedalism Henry M. McHenry; 12. Forelimb adaptations in Australopithecus afarensis Michelle S. M. Drapeau; 13. Hominin proximal femur morphology from the Tugen Hills to Flores Brian G. Richmond and William L. Jungers; 14. Daily rates of dentine formation and root extension rates in Paranthropus boisei, KNM-ER 1817, from Koobi Fora, Kenya M. Christopher Dean; 15. On the evolutionary development of early hominid molar teeth and the Gondolin Paranthropus molar Kevin L. Kuykendall; 16. Digital South African fossils: morphological studies using reference-based reconstruction and electronic preparation Gerhard W. Weber, Philipp Gunz, Simon Neubauer, Philipp Mitteroecker and Fred L. Bookstein; Part III. Modern Human Origins: Patterns, and Processes: 17. Body size in African Middle Pleistocene Homo Steven E. Churchill, Lee R. Berger, Adam Hartstone-Rose and Headman Zondo; 18. The African origin of recent humanity Milford H. Wolpoff and Sang-Hee Lee

Energy self-supply of large abattoir by sustainable waste utilization based on anaerobic mono-digestion

International Nuclear Information System (INIS)

Ortner, Markus; Wöss, David; Schumergruber, Alexander; Pröll, Tobias; Fuchs, Werner

2015-01-01

Highlights: • Successful implementation of a new waste and energy concept to large size abattoir. • 85% of slaughterhouse waste accumulated converted to energy by anaerobic digestion. • Coverage of abattoirs’ electrical and thermal energy demand between 50% and 60%. • Reduction of main energy and disposal cost by 63%. • Reduction of greenhouse gas emissions by 79%. - Abstract: Abattoirs have a large number of energy intensive processes. Beside energy supply, disposal costs of animal by-products (ABP) are the main relevant cost drivers. In this study, successful implementation of a new waste and energy management system based on anaerobic digestion is described. Several limitations and technical challenges regarding the anaerobic digestion of the protein rich waste material had to be overcome. The most significant problems were process imbalances such as foaming and floatation as well as high accumulation of volatile fatty acids and low biogas yields caused by lack of essential microelements, high ammonia concentrations and fluctuation in operation temperature. Ultimately, 85% of the waste accumulated during the slaughter process is converted into 2700 MW h thermal and 3200 MW h electrical energy in a biogas combined heat and power (CHP) plant. The thermal energy is optimally integrated into the production process by means of a stratified heat buffer. The energy generated by the biogas CHP-plant can cover a significant share of the energy requirement of the abattoir corresponding to 50% of heat and 60% of electric demand, respectively. In terms of annual cost for energy supply and waste disposal a reduction of 63% from 1.4 Mio € to about 0.5 Mio € could be achieved with the new system. The payback period of the whole investment is approximately 9 years. Beside the economic benefits also the positive environmental impact should be highlighted: a 79% reduction of greenhouse gas emissions from 4.5 Mio kg CO 2 to 0.9 Mio kg CO 2 annually was achieved

Inherited weaknesses control deformation in the flat slab region of Central Argentina

Science.gov (United States)

Stevens, A.; Carrapa, B.; Larrovere, M.; Aciar, R. H.

2015-12-01

The Sierras Pampeanas region of west-central Argentina has long been considered a geologic type-area for flat-slab induced thick-skinned deformation. Frictional coupling between the horizontal subducting plate and South American lithosphere from ~12 Ma to the present provides an obvious causal mechanism for the basement block uplifts that characterize this region. New low temperature thermochronometry data show basement rocks from the central Sierras Pampeanas (~ longitude 66 ̊ W) including Sierras Cadena de Paiman, Velasco and Mazan retain a cooling history of Paleozoic - Mesozoic tectonics events. Results from this study indicate that less than 2 km of basement has been exhumed since at least the Mesozoic. These trends recorded by both apatite fission track (AFT) and apatite helium (AHe) thermochronometry suggest that recent Mio-Pliocene thick-skinned deformation associated with flat-slab subduction follow inherited zones of weakness from Paleozoic terrane sutures and shear zones and Mesozoic rifting. If a Cenozoic foreland basin exisited in this region, its thickness was minimal and was controlled by paleotopography. Pre-Cenozoic cooling ages in these ranges that now reach as high as 4 km imply significant exhumation of basement rocks before the advent of flat slab subduction in the mid-late Miocene. It also suggests that thick-skinned deformation associated with flat slab subduction may at least be facilitated by inherited crustal-scale weaknesses. At the most, pre-existing zones of weakness may be required in regions of thick-skinned deformation. Although flat-slab subduction plays an important role in the exhumation of the Sierras Pampeanas, it is likely not the sole mechanism responsible for thick-skinned deformation in this region. This insight sheds light on the interpretation of modern and ancient regions of thick-skinned deformation in Cordilleran systems.

Gravimetry contributions to the study of the complex western Haouz aquifer (Morocco): Structural and hydrogeological implications

Science.gov (United States)

Chouikri, Ibtissam; el Mandour, Abdennabi; Jaffal, Mohammed; Baudron, Paul; García-Aróstegui, José-Luis; Manar, Ahmed; Casas, Albert

2016-03-01

This study provides new elements that illustrate the benefits of combining gravity, structural, stratigraphic and piezometric data for hydrogeological purposes. A combined methodology was applied to the western Haouz aquifer (Morocco), one of the main sources of water for irrigation and human consumption in the Marrakech region. First, a residual anomaly map was calculated from the Bouguer anomaly data. The computed map provided information on the ground density variation, revealing a strong control by a regional gradient. We then used various filtering techniques to delineate the major geological structures such as faults and basins: vertical and horizontal derivatives and upward continuation. This technique highlighted news structures and provided information on their dip. The gravity anomalies perfectly delineated the basement uplifts and the sedimentary thickening in depressions and grabens. The interpretation of gravimetric filtering, geological and hydrogeological data then highlighted two types of groundwater reservoirs, an unconfined aquifer hosted in conglomeratic mio-pliocene and quaternary rocks, covering the entire western Haouz and a deep confined aquifer contained in cenomanian-turonian limestone and eocene dolomitic formations in the south. Combining piezometric and residual anomaly maps revealed that groundwater flow and storage was in perfect agreement with the structures showing a negative anomaly, while structures with positive anomalies corresponded to groundwater divides. The study of gravity gradient zones by contact analysis enhanced the existing structural pattern of the study area and highlighted new structures, mainly oriented N70 and N130. The results of this study present a common framework and provide a notable step forward in the knowledge of the geometry and the groundwater flow pattern of the western Haouz aquifer, and will serve as a solid basis for a better water resource management.

Depósitos epitermales de baja sulfuración ricos en sulfuros de metales base, distrito aurífero La Carolina, San Luis, Argentina

Directory of Open Access Journals (Sweden)

Gallard-Esquivel María Cecilia

2011-12-01

Full Text Available Low-sulfidation epithermal base-metal sulfide-rich deposits, La Carolina gold-bearing district,San Luis, Argentina. La Carolina gold-bearing district is located at the western end of the Metallogenetic Belt of San Luis, which is spatially and genetically related to the mesosilicic volcanism of mio-pliocene age. The volcanic arc experienced an eastward migration, due to the flattening of the Nazca plate in the segment 27°-33°S, known as the Pampean flat-slab. At La Carolina, the volcanic activity occurred between 8.2 and 6.3 Ma. It encompasses lavas and pyroclastics of andesitic, dacitic, latitic and trachytic composition. The mesosilicic magmas belong to normal to high-k calc-alkaline and shoshonitic suites. Structural analysis shows that previous structures have strongly controlled the emplacement of volcanic rocks and related mineral deposits at La Carolina allowing to define a pullapart.In this gold-bearing district there are eigth small mineralized prospects. The mineralogy consists of pyrite, arsenic rich pyrite, galena, sphalerite, marcasite, melnikovite, chalcopyrite, pyrrhotite, arsenopyrite, tennantitetetrahedrite, digenite, covellite, bornite, pyrargiryte, hessite, silvanite, pearceite, argirodite, gold, silver, greigite, boulangerite, jamesonite and electrum. The gangue consists of quartz, calcite, chalcedony and minor adularia.The hydrothermal alteration is widespread and comprise phyllic and argillic mineral assemblages characterized by sericite, illite, interstratified I/S, and silicic; propylitic alteration is also present as an outer halo. Fluid inclusions studies show that the formation temperatures range between 230º to 330º C. Boiling and mixing with meteoric water led to mineral precipitation. Based on the mineralogy, textures, hydrothermal alteration, formation temperatures,fluid chemistry and prospective geochemistry the mineralizations have been classified as low-sulfidation epithermal base-metal sulfide-rich deposits.

First fossil insectivores from Flores

NARCIS (Netherlands)

Hoek Ostende, van den L.W.; Berch, van der G.; Awe Due, R.

2006-01-01

The hominid bearing strata from the Liang Bua cave on Flores have yielded a large amount of microvertebrate remains. Among these are three mandibles of shrews, the first record of fossil insectivores from the island. The fossils, representing two different species, are not referable to any of the

Global CO{sub 2} emissions 2017. Still no breakthrough can be seen, but the signs of a trend reversal are increasing; Weltweite CO{sub 2}-Emissionen 2017. Noch kein Durchbruch erkennbar, doch mehren sich die Zeichen einer Trendumkehr

Energy Technology Data Exchange (ETDEWEB)

Ziesing, Hans-Joachim

2017-09-15

In 2016 global CO{sub 2} emissions according to provisional calculations rose only slightly compared to 2015 with 0.4%. As a result, the average long-term growth of 1.7% (from 1990 to 2015) was once again clearly slowed down as in the previous year. As a result, CO{sub 2} emissions in 2016 reached a new peak of 33.3 billion tonnes. Although this still does not signal a trend reversal, but CO{sub 2} emissions have declined in many countries, particularly in some industrialized countries. For example. CO{sub 2} emissions in the Annex I countries were reduced by a total of 0.7% or around 94 million tonnes. This is mainly attributed to developments in the USA (-1.7% or 90.0 million tonnes), Russia (-2.0% or 32.6 million tonnes), Great Britain (-5.5% or 23.0 million tonnes) and Japan (-1.5% or 18.0 million tonnes). Encouraging is also the fact that CO{sub 2} emissions in China, the country with by far the highest emissions, have declined in 2016 as in the previous year - albeit with 0.2% quite weakly. It is less positive that CO{sub 2} emissions in the EU-28 have increased again, with the exception of Great Britain, Portugal, Spain and Bulgaria, contrary to EU-wide targets. [German] Im Jahr 2016 sind die weltweiten CO{sub 2}-Emissionen nach vorlaeufigen Berechnungen gegenueber 2015 mit 0,4 % nur schwach gestiegen. Damit wurde der langfristige Zuwachs von jahresdurchschnittlich 1,7 % (von 1990 bis 2015) wie schon im Vorjahr erneut deutlich gebremst. Im Ergebnis erreichten die CO{sub 2}-Emissionen 2016 mit reichlich 33,3 Mrd. t einen neuen Spitzenwert. Das signalisiert zwar noch keine Trendwende, doch sind die CO{sub 2}-Emissionen in zahlreichen Laendern, insbesondere in etlichen Industrielaendern, gesunken. Bspw. wurden die CO{sub 2}-Emissionen in den Annex-I-Laendern gesamthaft um 0,7 % oder rund 94 Mio. t reduziert. Dies ist vor allem auf die Entwicklung in den USA (-1,7 % oder 90,0 Mio. t), Russland (-2,0 % oder 32,6 Mio. t), Grossbritannien (-5,5 % oder 23,0 Mio. t

Fossil evidence for the origin of Homo sapiens.

Science.gov (United States)

Schwartz, Jeffrey H; Tattersall, Ian

2010-01-01

Our species Homo sapiens has never received a satisfactory morphological definition. Deriving partly from Linnaeus's exhortation simply to "know thyself," and partly from the insistence by advocates of the Evolutionary Synthesis in the mid-20th Century that species are constantly transforming ephemera that by definition cannot be pinned down by morphology, this unfortunate situation has led to huge uncertainty over which hominid fossils ought to be included in H. sapiens, and even over which of them should be qualified as "archaic" or as "anatomically modern," a debate that is an oddity in the broader context of paleontology. Here, we propose a suite of features that seems to characterize all H. sapiens alive today, and we review the fossil evidence in light of those features, paying particular attention to the bipartite brow and the "chin" as examples of how, given the continuum from developmentally regulated genes to adult morphology, we might consider features preserved in fossil specimens in a comparative analysis that includes extant taxa. We also suggest that this perspective on the origination of novelty, which has gained a substantial foothold in the general field of evolutionary developmental biology, has an intellectual place in paleoanthropology and hominid systematics, including in defining our species, H. sapiens. Beginning solely with the distinctive living species reveals a startling variety in morphologies among late middle and late Pleistocene hominids, none of which can be plausibly attributed to H. sapiens/H. neanderthalensis admixture. Allowing for a slightly greater envelope of variation than exists today, basic "modern" morphology seems to have appeared significantly earlier in time than the first stirrings of the modern symbolic cognitive system. Copyright © 2010 Wiley-Liss, Inc.

Early Acheulean technology in the Rietputs Formation, South Africa, dated with cosmogenic nuclides.

Science.gov (United States)

Gibbon, Ryan J; Granger, Darryl E; Kuman, Kathleen; Partridge, Timothy C

2009-02-01

An absolute dating technique based on the build-up and decay of (26)Al and (10)Be in the mineral quartz provides crucial evidence regarding early Acheulean hominid distribution in South Africa. Cosmogenic nuclide burial dating of an ancient alluvial deposit of the Vaal River (Rietputs Formation) in the western interior of South Africa shows that coarse gravel and sand aggradation there occurred ca 1.57+/-0.22Ma, with individual ages of samples ranging from 1.89+/-0.19 to 1.34+/-0.22Ma. This was followed by aggradation of laminated and cross-bedded fine alluvium at ca 1.26+/-0.10Ma. The Rietputs Formation provides an ideal situation for the use of the cosmogenic nuclide burial dating method, as samples could be obtained from deep mining pits at depths ranging from 7 to 16 meters. Individual dates provide only a minimum age for the stone tool technology preserved within the deposits. Each assemblage represents a time averaged collection. Bifacial tools distributed throughout the coarse gravel and sand unit can be assigned to an early phase of the Acheulean. This is the first absolute radiometric dated evidence for early Acheulean artefacts in South Africa that have been found outside of the early hominid sites of the Gauteng Province. These absolute dates also indicate that handaxe-using hominids inhabited southern Africa as early as their counterparts in East Africa. The simultaneous appearance of the Acheulean in different parts of the continent implies relatively rapid technology development and the widespread use of large cutting tools in the African continent by ca 1.6Ma.

Evolution of life history and behavior in Hominidae: towards phylogenetic reconstruction of the chimpanzee-human last common ancestor.

Science.gov (United States)

Duda, Pavel; Zrzavý, Jan

2013-10-01

The origin of the fundamental behavioral differences between humans and our closest living relatives is one of the central issues of evolutionary anthropology. The prominent, chimpanzee-based referential model of early hominin behavior has recently been challenged on the basis of broad multispecies comparisons and newly discovered fossil evidence. Here, we argue that while behavioral data on extant great apes are extremely relevant for reconstruction of ancestral behaviors, these behaviors should be reconstructed trait by trait using formal phylogenetic methods. Using the widely accepted hominoid phylogenetic tree, we perform a series of character optimization analyses using 65 selected life-history and behavioral characters for all extant hominid species. This analysis allows us to reconstruct the character states of the last common ancestors of Hominoidea, Hominidae, and the chimpanzee-human last common ancestor. Our analyses demonstrate that many fundamental behavioral and life-history attributes of hominids (including humans) are evidently ancient and likely inherited from the common ancestor of all hominids. However, numerous behaviors present in extant great apes represent their own terminal autapomorphies (both uniquely derived and homoplastic). Any evolutionary model that uses a single extant species to explain behavioral evolution of early hominins is therefore of limited use. In contrast, phylogenetic reconstruction of ancestral states is able to provide a detailed suite of behavioral, ecological and life-history characters for each hypothetical ancestor. The living great apes therefore play an important role for the confident identification of the traits found in the chimpanzee-human last common ancestor, some of which are likely to represent behaviors of the fossil hominins. Copyright © 2013 Elsevier Ltd. All rights reserved.

Littoral sedimentation of rift lakes: an illustrated overview from the modern to Pliocene Lake Turkana (East African Rift System, Kenya)

Science.gov (United States)

Schuster, Mathieu; Nutz, Alexis

2015-04-01

Existing depositional models for rift lakes can be summarized as clastics transported by axial and lateral rivers, then distributed by fan-deltas and/or deltas into a standing water body which is dominated by settling of fine particles, and experiencing occasional coarser underflows. Even if known from paleolakes and modern lakes, reworking of clastics by alongshore drift, waves and storms are rarely considered in depositional models. However, if we consider the lake Turkana Basin (East African Rift System, Kenya) it is obvious that this vision is incomplete. Three representative time slices are considered here: the modern Lake Turkana, the Megalake Turkana which developed thanks to the African Humid Period (Holocene), and the Plio-Pleistocene highstand episodes of paleolake Turkana (Nachukui, Shungura and Koobi Fora Formations, Omo Group). First, remarkable clastic morphosedimentary structures such as beach ridges, spits, washover fans, lagoons, or wave-dominated deltas are very well developed along the shoreline of modern lake Turkana, suggesting strong hydrodynamics responsible for a major reworking of the fluvial-derived clastics all along the littoral zone (longshore and cross-shore transport) of the lake. Similarly, past hydrodynamics are recorded from prominent raised beach ridges and spits, well-preserved all around the lake, above its present water-level (~360 m asl) and up to ~455 m. These large-scale clastic morphosedimentary structures also record the maximum extent of Megalake Turkana during the African Humid Period, as well as its subsequent regression forced by the end of the Holocene climatic optimum. Several hundreds of meters of fluvial-deltaic-lacustrine deposits spanning the Pliocene-Pleistocene are exposed in the Turkana basin thanks to tectonic faulting. These deposits are world famous for their paleontological and archeological content that documents the very early story of Mankind. They also preserve several paleolake highstand episodes with

Asymmetrical, inversely graded, upstream-migrating cyclic steps in marine settings: Late Miocene-early Pliocene Fish Creek-Vallecito Basin, southern California

Science.gov (United States)

Gong, Chenglin; Chen, Liuqin; West, Logan

2017-10-01

Cyclic steps are ubiquitous in modern sedimentary environments, yet their recognition remains sparse in the rock record. Here, we interpret three sets of undulating backsets (1 to 3) recognized in the late Miocene-early Pliocene Latrania Formation in the Anza-Borrego Desert, the Fish Creek-Vallecito Basin, southern California, USA as the first cm- to dm-scale outcrop record of cyclic steps, based on asymmetrical cross-sections, upstream migration, and inversely graded laminae. Upstream migration and asymmetrical cross-sections of backsets and concomitant backset laminae are attributed to supercritical-to-subcritical flow transitions through weak hydraulic jumps, which are composed of: (i) thin (tens of centimetres) and slower (reported as flow velocities (Ū) of 0.45 to 1.45 m s- 1, with mean value of Ū = 0.89 m s- 1) subcritical (represented by internal Froude numbers (Fr) of 0.67 to 0.99, with mean value of Fr = 0.84) turbidity currents on the stoss sides, and (ii) thin (tens of centimetres) and faster (reported as Ū of 0.99 to 4.03 m s- 1, with mean value of Ū = 2.24 m s- 1) supercritical (represented by Fr of 1.84 to 3.07, with mean value of Fr = 2.42) turbidity flows on the lee sides. The inversely graded laminae in the troughs of backsets are 2 to 5 cm thick, and consist of two discrete divisions: (i) 1 to 2 cm thick, lower finer-grained divisions made up of parallel laminated siltstones, overlain by very fine- to fine-grained sandstones, and (ii) 2 to 3 cm thick, upper divisions composed of medium- to coarse-grained sandstones, with sporadic occurrence of subrounded pebbles. These inversely graded laminae are related to stratified, collisional and/or frictional traction carpets under conditions of high fall-out rates. Due to the poor preservation potential of cyclic steps, the rock record of cyclic steps is generally considered to be rare. The present outcrop-based study presents a detailed analysis of sedimentary facies, growth patterns, and flow

Defend the Approaches

National Research Council Canada - National Science Library

Patterson, Mark A

2008-01-01

.... territories to provide for better discrimination by Maritime Interdiction Operations (MIO). This paper argues that given the nature of the WMD threat, the United States will be better defended by forces operating closer to U.S...

Sadhana | Indian Academy of Sciences

Indian Academy of Sciences (India)

As a non-hominid comparison set, we consider a random population of five-link robots with simplified joint angle and torque constraints. We generate 20,000 such robot models and sequentially optimize their throwing motion. Since good initial guesses are needed for each optimization, the robots are first arranged in ...

Evolution of Humans: Understanding the Nature and Methods of Science through Cooperative Learning

Science.gov (United States)

Lee, Yeung Chung

2011-01-01

This article describes the use of an enquiry-based approach to the study of human evolution in a practical context, integrating role-playing, jigsaw cooperative learning and scientific argumentation. The activity seeks to unravel the evolutionary relationships of five hominids and one ape from rather "messy" evidence. This approach enhanced the…

The evolutionary significance of the Wajak skulls

NARCIS (Netherlands)

Storm, P.

1995-01-01

Ever since their description by Dubois (1920, 1922) the Wajak skulls Java) have played an important role in the discussions on the evolution of modern humans in Australasia. Because of the robust morphology of the skull, Wajak Man was seen as a link between Pleistocene hominids from Java (Solo) and

Does improvement in maternal attachment representations predict greater maternal sensitivity, child attachment security and lower rates of relapse to substance use? A second test of Mothering from the Inside Out treatment mechanisms.

Science.gov (United States)

Suchman, Nancy E; DeCoste, Cindy; Borelli, Jessica L; McMahon, Thomas J

2018-02-01

In this study, we replicated a rigorous test of the proposed mechanisms of change associated with Mothering from the Inside out (MIO), an evidence-based parenting therapy that aims to enhance maternal reflective functioning and mental representations of caregiving in mothers enrolled in addiction treatment and caring for young children. First, using data from 84 mothers who enrolled in our second randomized controlled trial, we examined whether therapist fidelity to core MIO treatment components predicted improvement in maternal reflective functioning and mental representations of caregiving, even after taking fidelity to non-MIO components into account. Next, we examined whether improvement in directly targeted outcomes (e.g., maternal mentalizing and mental representations of caregiving) led to improvements in the indirectly targeted outcome of maternal caregiving sensitivity, even after controlling for other plausible competing mechanisms (e.g., improvement in maternal psychiatric distress and substance use). Third, we examined whether improvement in targeted parenting outcomes (e.g., maternal mentalizing, mental representations of caregiving and caregiving sensitivity) was associated in improvement in child attachment status, even after controlling for competing mechanisms (e.g., improvement in maternal psychiatric distress and substance use). Finally, we examined whether improvement in maternal mentalizing and caregiving representations was associated with a reduction in relapse to substance use. Support was found for the first three tests of mechanisms but not the fourth. Implications for future research and intervention development are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

Chromosome Connections: Compelling Clues to Common Ancestry

Science.gov (United States)

Flammer, Larry

2013-01-01

Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

The Power of Natural Selection: A Guided Investigation of Three Case Studies

Science.gov (United States)

Beachly, William

2010-01-01

I describe a quantitative approach to three case studies in evolution that can be used to challenge college freshmen to explore the power of natural selection and ask questions that foster a deeper understanding of its operation and relevance. Hemochromatosis, the peppered moth, and hominid cranial capacity are investigated with a common algebraic…

Original Synthetic Article: The relationships between occlusion and ...

African Journals Online (AJOL)

Materials and Methods: These correlations were analyzed by using a metric methodology applied to x-rays or CT scan images of extant and fossil skulls. Results and conclusions: This approach presents major interests for the study of occluso-postural balances in fossil hominids as well as for the analysis of the evolutionary ...

Power generation from water salinity gradient via osmosis and reverse osmosis

International Nuclear Information System (INIS)

Ivanov, Milancho

2015-01-01

To reduce dependence on fossil fuels, while at the same time to meet the growing energy demands of the world, it is necessary to explore and promote new alternative energy sources. One such type of renewable energy sources, which recently gained greater credibility is the energy extracted from the water salinity gradient, which is also called blue energy. In this research project will be described a new model of osmotic power plant (MIOS plant), which uses a combination of reverse osmosis and osmosis to convert the energy from the water salinity gradient into electricity. MIOS plant can be built as a vessel anywhere on the surface of the oceans or in the form of dam on the land, which will have a huge advantage over existing plants that can be built only on mouths of rivers. (author)

Patterns of dental development in Homo, Australopithecus, Pan, and Gorilla.

Science.gov (United States)

Smith, B H

1994-07-01

Smith ([1986] Nature 323:327-330) distinguished patterns of development of teeth of juvenile fossil hominids as being "more like humans" or "more like apes" based on statistical similarity to group standards. Here, this central tendency discrimination (CTD) is tested for its ability to recognize ape and human patterns of dental development in 789 subadult hominoids. Tooth development of a modern human sample (665 black southern Africans) was scored entirely by an outside investigator; pongid and fossil hominid samples (59 Pan, 50 Gorilla, and 14 fossil hominids) were scored by the author. The claim of Lampl et al. ([1993] Am. J. Phys. Anthropol. 90:113-127) that Smith's 1986 method succeeds in only 8% of human cases was not sustained. Figures for overall success of classification (87% humans, 68% apes) mask important effects of teeth sampled and age class. For humans, the power of CTD varied between 53% and 92% depending on the number and kind of teeth available--nearly that of a coin toss when data described only two nearby teeth, but quite successful with more teeth or distant teeth. For apes, only age class affected accuracy: "Infant" apes (M1 development or = root 1/4), however, were correctly discriminated in 87% of cases. Overall, CTD can be considered reliable (accuracy of 92% for humans and 88% for apes) when data contrast development of distant dental fields and subjects are juveniles (not infants). Restricting analysis of fossils to specimens satisfying these criteria, patterns of dental development of gracile australopithecines and Homo habilis remain classified with African apes. Those of Homo erectus and Neanderthals are classified with humans, suggesting that patterns of growth evolved substantially in the Hominidae. To standardize future research, the computer program that operationalizes CTD is now available.

Rapid subsidence and stacked Gilbert-type fan deltas, Pliocene Loreto basin, Baja California Sur, Mexico

Science.gov (United States)

Dorsey, Rebecca J.; Umhoefer, Paul J.; Renne, Paul R.

1995-08-01

Pliocene nonmarine to marine sedimentary rocks exposed in the Loreto basin, Baja California Sur, provide a record of syntectonic subsidence and sedimentation in a transform-rift basin that developed along the western margin of the Gulf of California. A thick sequence of twelve Gilbert-type fan deltas, having a total measured thickness of about 615 m, accumulated near the fault-bounded southwestern margin of this basin. Based on stratal geometries and lithofacies associations, sedimentary rocks are divided into Gilbert-delta topset, foreset and bottomset strata, shell beds and background shallow-marine shelf deposits. Topset strata of each Gilbert-type delta cycle are capped by laterally persistent molluscan shell beds containing diverse assemblages of bivalves, pectens, oysters, gastropods and echinoids. These shell beds are interpreted to be condensed intervals that record sediment starvation during abandonment of the fan-delta plain. Delta abandonment may have been caused by large episodic faulting events, which submerged each pre-existing fan-delta plain, substantially slowed detrital input by drowning of alluvial feeder channels, and created new accommodation space for each new Gilbert-type fan delta. Alternatively, it is possible that delta-plain abandonment was caused by upstream avulsions and autocyclic lateral switching of fan-delta lobes during relatively uniform rates of slip along the basin-bounding fault. Two contrasting, plausible basin models are proposed for the Loreto basin: (1) asymmetric subsidence along a high-angle oblique-slip normal fault, producing a classic half-graben basin geometry with vertically stacked Gilbert-type fan deltas; or (2) lateral stacking and horizontal displacement of strata away from a relatively fixed depocenter due to fault movement in the releasing bend of a listric strike-slip fault. We favor the first model because field relations and simple geometric constraints suggest that most of the total measured section

Geochemistry, mineralogy, and zircon U-Pb-Hf isotopes in peraluminous A-type granite xenoliths in Pliocene-Pleistocene basalts of northern Pannonian Basin (Slovakia)

Science.gov (United States)

Huraiová, Monika; Paquette, Jean-Louis; Konečný, Patrik; Gannoun, Abdel-Mouhcine; Hurai, Vratislav

2017-08-01

Anorogenic granite xenoliths occur in alkali basalts coeval with the Pliocene-Pleistocene continental rifting of the Pannonian Basin. Observed granite varieties include peraluminous, calcic to peralkalic, magnesian to ferroan types. Quartz and feldspars are dominant rock-forming minerals, accompanied by minor early ilmenite and late magnetite-ulvöspinel. Zircon and Nb-U-REE minerals (oxycalciopyrochlore, fergusonite, columbite) are locally abundant accessory phases in calc-alkalic types. Absence of OH-bearing Fe, Mg-silicates and presence of single homogeneous feldspars (plagioclase in calcic types, anorthoclase in calc-alkalic types, ferrian Na-sanidine to anorthoclase in alkalic types) indicate water-deficient, hypersolvus crystallization conditions. Variable volumes of interstitial glass, absence of exsolutions, and lacking deuteric hydrothermal alteration and/or metamorphic/metasomatic overprint are diagnostic of rapid quenching from hypersolidus temperatures. U-Pb zircon ages determined in calcic and calc-alkalic granite xenoliths correspond to a time interval between 5.7 and 5.2 Ma. Positive ɛHf values (14.2 ± 3.9) in zircons from a 5.2-Ma-old calc-alkalic granite xenolith indicate mantle-derived magmas largely unaffected by the assimilation of crustal material. This is in accordance with abundances of diagnostic trace elements (Rb, Y, Nb, Ta), indicating A1-type, OIB-like source magmas. Increased accumulations of Nb-U-REE minerals in these granites indicate higher degree of the magmatic differentiation reflected in Rb-enrichment, contrasting with Ba-enrichment in barren xenoliths. Incipient charnockitization, i.e. orthopyroxene and ilmenite crystallization from interstitial silicate melt, was observed in many granite xenoliths. Thermodynamic modeling using pseudosections showed that the orthopyroxene growth may have been triggered by water exsolution from the melt during ascent of xenoliths in basaltic magma. Euhedral-to-skeletal orthopyroxene growth

Buccal dental microwear variability in extant African Hominoidea: taxonomy versus ecology.

Science.gov (United States)

Galbany, Jordi; Estebaranz, Ferran; Martínez, Laura M; Pérez-Pérez, Alejandro

2009-07-01

Buccal microwear patterns on teeth are good indicators of the abrasiveness of foodstuffs and have been used to trace the dietary habits of fossil species, including primates and hominids. However, few studies have addressed the variability of this microwear. The abrasiveness of dietary components depends not only on the hardness of the particles ingested, but also on the presence of dust and other exogenous elements introduced during food processing. These elements are responsible for the microwear typology observed on the enamel surfaces of primate teeth. Here we analyzed the variability of buccal microwear patterns in African Great Apes (Gorilla gorilla and Pan troglodytes), using tooth molds obtained from the original specimens held in several osteological collections. Our results suggest that ecological adaptations at subspecies or population level account for differences in microwear patterns, which are attributed to habitat and ecological conditions within populations rather than differences between species. The findings from studies on the variability of buccal dental microwear in extant species will contribute to a better understanding of extinct hominids' diet and ecology.

Plio-Pleistocene climate sensitivity evaluated using high-resolution CO2 records.

Science.gov (United States)

Martínez-Botí, M A; Foster, G L; Chalk, T B; Rohling, E J; Sexton, P F; Lunt, D J; Pancost, R D; Badger, M P S; Schmidt, D N

2015-02-05

Theory and climate modelling suggest that the sensitivity of Earth's climate to changes in radiative forcing could depend on the background climate. However, palaeoclimate data have thus far been insufficient to provide a conclusive test of this prediction. Here we present atmospheric carbon dioxide (CO2) reconstructions based on multi-site boron-isotope records from the late Pliocene epoch (3.3 to 2.3 million years ago). We find that Earth's climate sensitivity to CO2-based radiative forcing (Earth system sensitivity) was half as strong during the warm Pliocene as during the cold late Pleistocene epoch (0.8 to 0.01 million years ago). We attribute this difference to the radiative impacts of continental ice-volume changes (the ice-albedo feedback) during the late Pleistocene, because equilibrium climate sensitivity is identical for the two intervals when we account for such impacts using sea-level reconstructions. We conclude that, on a global scale, no unexpected climate feedbacks operated during the warm Pliocene, and that predictions of equilibrium climate sensitivity (excluding long-term ice-albedo feedbacks) for our Pliocene-like future (with CO2 levels up to maximum Pliocene levels of 450 parts per million) are well described by the currently accepted range of an increase of 1.5 K to 4.5 K per doubling of CO2.

Plio-Pleistocene climate sensitivity evaluated using high-resolution CO2 records

Science.gov (United States)

Martínez-Botí, M. A.; Foster, G. L.; Chalk, T. B.; Rohling, E. J.; Sexton, P. F.; Lunt, D. J.; Pancost, R. D.; Badger, M. P. S.; Schmidt, D. N.

2015-02-01

Theory and climate modelling suggest that the sensitivity of Earth's climate to changes in radiative forcing could depend on the background climate. However, palaeoclimate data have thus far been insufficient to provide a conclusive test of this prediction. Here we present atmospheric carbon dioxide (CO2) reconstructions based on multi-site boron-isotope records from the late Pliocene epoch (3.3 to 2.3 million years ago). We find that Earth's climate sensitivity to CO2-based radiative forcing (Earth system sensitivity) was half as strong during the warm Pliocene as during the cold late Pleistocene epoch (0.8 to 0.01 million years ago). We attribute this difference to the radiative impacts of continental ice-volume changes (the ice-albedo feedback) during the late Pleistocene, because equilibrium climate sensitivity is identical for the two intervals when we account for such impacts using sea-level reconstructions. We conclude that, on a global scale, no unexpected climate feedbacks operated during the warm Pliocene, and that predictions of equilibrium climate sensitivity (excluding long-term ice-albedo feedbacks) for our Pliocene-like future (with CO2 levels up to maximum Pliocene levels of 450 parts per million) are well described by the currently accepted range of an increase of 1.5 K to 4.5 K per doubling of CO2.

Differentiation between the traces of predation of muricids and naticids in Spanish Pliocene Chlamys

Directory of Open Access Journals (Sweden)

Reyment, R. A.

1988-08-01

Full Text Available The statistical analysis of holes drilled in species of the bivalve genus Chlamys from localities in the Lower Pliocene of Southern Spain throws light on aspects of muricid and naticid predation. Discriminant function analysis was found to be a useful means of identifying the nature of boreholes, with but slight errors of identification for known specimens. In particular, significant differences in relationships between predators and prey could be established. The question as to whether preferred locations of boreholes occur could be answered affirmatively for muricids. Also for muricids, the majority of the observed boreholes (74.1% are concentrated to the region fo the adductor muscle: such a relationship could not be definitely proven for naticids (36.9% within the adduetor muscle field. An association between the site of the prey and predator could only be demonstrated for naticids in connexion with prey of several species and genera. There is a strong association between the size of the prey and the site chosen for drilling for both groups of predators. There is indecisive evidence for a correlation between the location and size a drillhole for naticids, but probably not for muricids. The strategy of seleetion of a drilling site by muricids seems to• be to weaken the function of the adductor muscle in the monomyarian Chlamys, hence facilitating access to the víscera. In general, multivariate analytical procedures, and especiaIly the method of canonical correlations, were found lo aid greatly the interpretation of the quantitative observations.El análisis estadístico de los orificios perforados en las especies del género Chlamys del Plioceno Inferior del Sur de España aclara algunos aspectos muy interesantes sobre la predacción de los murícidos y natícidos. El análisis de la función discriminante se ha determinado como un método muy útil para identificar la naturaleza de los orificios, son muy pocos los errores de

The evolution of lethal intergroup violence

OpenAIRE

Kelly, Raymond C.

2005-01-01

Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

The evolution of lethal intergroup violence.

Science.gov (United States)

Kelly, Raymond C

2005-10-25

Recent findings and analyses in evolutionary biology, archaeology, and ethnology provide a favorable conjuncture for examining the evolution of lethal intergroup violence among hominids during the 2.9-million-year Paleolithic time span. Here, I seek to identify and investigate the main turning points in this evolutionary trajectory and to delineate the periodization that follows from this inquiry.

Managing the Quality of Experience in the Multimedia Internet of Things: A Layered-Based Approach.

Science.gov (United States)

Floris, Alessandro; Atzori, Luigi

2016-12-02

This paper addresses the issue of evaluating the Quality of Experience (QoE) for Internet of Things (IoT) applications, with particular attention to the case where multimedia content is involved. A layered IoT architecture is firstly analyzed to understand which QoE influence factors have to be considered in relevant application scenarios. We then introduce the concept of Multimedia IoT (MIoT) and define a layered QoE model aimed at evaluating and combining the contributions of each influence factor to estimate the overall QoE in MIoT applications. Finally, we present a use case related to the remote monitoring of vehicles during driving practices, which is used to validate the proposed layered model, and we discuss a second use case for smart surveillance, to emphasize the generality of the proposed framework. The effectiveness in evaluating classes of influence factors separately is demonstrated.

Lithostratigraphy, petrography, biostratigraphy, and strontium-isotope stratigraphy of the surficial aquifer system of western Collier County, Florida

Science.gov (United States)

Edwards, L.E.; Weedman, S.D.; Simmons, R.; Scott, T.M.; Brewster-Wingard, G. L.; Ishman, S.E.; Carlin, N.M.

1998-01-01

In 1996, seven cores were recovered in western Collier County, southwestern Florida, to acquire subsurface geologic and hydrologic data to support ground-water modeling efforts. This report presents the lithostratigraphy, X-ray diffraction analyses, petrography, biostratigraphy, and strontium-isotope stratigraphy of these cores. The oldest unit encountered in the study cores is an unnamed formation that is late Miocene. At least four depositional sequences are present within this formation. Calculated age of the formation, based on strontium-isotope stratigraphy, ranges from 9.5 to 5.7 Ma (million years ago). An unconformity within this formation that represents a hiatus of at least 2 million years is indicated in the Old Pump Road core. In two cores, Collier-Seminole and Old Pump Road, the uppermost sediments of the unnamed formation are not dated by strontium isotopes, and, based on the fossils present, these sediments could be as young as Pliocene. In another core (Fakahatchee Strand-Ranger Station), the upper part of the unnamed formation is dated by mollusks as Pliocene. The Tamiami Formation overlies the unnamed formation throughout the study area and is represented by the Ochopee Limestone Member. The unit is Pliocene and probably includes the interval of time near the early/late Pliocene boundary. Strontium-isotope analysis indicates an early Pliocene age (calculated ages range from 5.1 to 3.5 Ma), but the margin of error includes the latest Miocene and the late Pliocene. The dinocyst assemblages in the Ochopee typically are not age-diagnostic, but, near the base of the unit in the Collier-Seminole, Jones Grade, and Fakahatchee Strand State Forest cores, they indicate an age of late Miocene or Pliocene. The molluscan assemblages indicate a Pliocene age for the Ochopee, and a distinctive assemblage of Carditimera arata and Chione cortinaria in several of the cores specifically indicates an age near the early/late Pliocene boundary. Undifferentiated sands

Relations between tectonics and sedimentation along the Eastern Sardinian margin (Western Tyrrhenian Sea) : from rifting to reactivation

Science.gov (United States)

Gaullier, Virginie; Chanier, Frank; Vendeville, Bruno; Lymer, Gaël; Maillard, Agnès; Thinon, Isabelle; Lofi, Johanna; Sage, Françoise; Giresse, Pierre; Bassetti, Maria-Angela

2014-05-01

The offshore-onshore project "METYSS-METYSAR" aims at better understand the Miocene-Pliocene relationships between crustal tectonics, salt tectonics, and sedimentation along the Eastern Sardinian margin, Western Tyrrhenian Sea. In this key-area, the Tyrrhenian back-arc basin underwent recent rifting (9-5 Ma), pro parte coeval with the Messinian Salinity Crisis (MSC, 5.96-5.33 Ma), sea-floor spreading starting during Pliocene times. Thereby, the Tyrrhenian basin and the Eastern Sardinian margin are excellent candidates for studying the mechanisms of extreme lithospheric stretching and thinning, the role of pre-existing structural fabric during and after rifting, and the reactivation of a passive margin and the associated deformation and sedimentation patterns during the MSC. We looked at the respective contributions of crustal and salt tectonics in quantifying vertical and horizontal movements, using especially the seismic markers of the MSC. Overall, we delineate the history of rifting and tectonic reactivation in the area. The distribution maps respectively of the Messinian Erosion Surface and of Messinian units (Upper Unit and Mobile Unit) show that a rifted basin already existed by Messinian time. This reveals a major pre-MSC rifting across the entire domain. Because salt tectonics can create fan-shaped geometries in sediments, syn-rift deposits have to be carefully re-examined in order to decipher the effects of crustal tectonics (rifting) and thin-skinned salt tectonics. Our data surprisingly show that there are no clues for Messinian syn-rift sediments along the East-Sardinia Basin and Cornaglia Terrace, hence no evidence for rifting after Late Tortonian times. Nevertheless, widespread deformation occurred during the Pliocene and can only be attributed to post-rift reactivation. This reactivation is characterized not only by normal faulting but also by contractional structures. Some Pliocene vertical movements caused localized gravity gliding of the mobile

Pliocene paleoenvironment evolution as interpreted from 3D-seismic data in the southern North Sea, Dutch offshore sector

Energy Technology Data Exchange (ETDEWEB)

Kuhlmann, Gesa [Faculty of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht (Netherlands); Wong, Theo E. [Faculty of Earth Sciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht (Netherlands); TNO-NITG, National Geological Survey of the Netherlands, Princetonlaan 6, 3584 CB Utrecht (Netherlands)

2008-02-15

A high-resolution 3D-seismic survey from the Dutch offshore sector has been interpreted and subsequently correlated with existing regional seismo-stratigraphic concepts derived from conventional 2D-seismic data sets. The interpreted 13 seismic units have been related to a newly established chrono-stratigraphic framework [Kuhlmann et al., 2006a, b. Chronostratigraphy of Late Neogene sediments in the southern North Sea Basin and paleoenvironmental interpretations. Palaeogeography, Palaeoclimatology, Palaeoecology, 239, 426-455; Integrated chronostratigraphy of the Pliocene-Pleistocene interval and its relation to the regional stratigraphical stages in the southern North Sea region. Netherlands Journal of Geosciences-Geologie en Mijnbouw, 85(1), 19-35] resulting in up-dated age control for the seismic units. The generation of amplitude maps, time slices and isopach maps from the 3D-seismic data enabled detailed spatial and temporal reconstruction regarding the paleoenvironmental and climatological development as depicted by Kuhlmann et al. [2006a. Chronostratigraphy of Late Neogene sediments in the southern North Sea Basin and paleoenvironmental interpretations. Palaeogeography, Palaeoclimatology, Palaeoecology, 239, 426-455]. The lowermost seismic units S1-S4 comprise condensed Middle Miocene to Piacencian sediments, deposited under warm open marine conditions. These sediments show a uniform seismic facies of low-amplitude reflectors. The boundary of seismic unit S4-S5 (around 2.6 Ma) delineates a shift towards generally colder climate conditions that are connected to the onset of Northern Hemisphere Glaciation. Seismic unit S5 includes alternations of warmer and colder periods. During warmer periods, bottom currents generated elongated structures (2.5-4 km long, 300-500 m wide) on the horizon display. These layers show as well shallow gas accumulations with a more regional extent and are related to coarser-grained sediments sealed by clayey sediments of the cold

Climate protection by reducing the emissions of greenhouse gases in households and the tertiary sector through climate-conscious behaviour. Vol. 2; Klimaschutz durch Minderung von Treibhausgasemissionen im Bereich Haushalte und Kleinverbrauch durch klimagerechtes Verhalten. Bd. 2. Gewerbe, Handel und Dienstleistung

Energy Technology Data Exchange (ETDEWEB)

Boede, U; Gruber, E [Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (ISI), Karlsruhe (Germany); Deutscher, P; Elsberger, M; Rouvel, L [Technische Univ., Muenchen (Germany). Lehrstuhl fuer Energiewirtschaft und Innovationsforschung; Brakhage, A; Jaekel, M [Abacus, Trier (Germany); Renner, G [Innovative Energieberatung, Koeln (Germany); Brohmann, B; Cames, M; Herold, A

2000-08-01

The aim of the project was to identify areas in households and the tertiary sector in which changes in behaviour could result in energy conservation and thus a reduction of greenhouse gas emissions, and to quantify the potentials for 1995, 2005 and 2020. A second focus was on the analysis and evaluation of programmes and instruments to realise the potentials. With literature evaluation, expert interviews, and a household servey potentials and further technical development have been identified. In sum, behavioural measures can contribute to the CO2 reduction by 64 million tons in 1995 in households and 27 in the commercial sector in which the potential decreases to 18 million tons in 2020 due to the autonomous technical development. Adequate promotion programmes can help to realise 20-30% of the potential by 2020. (orig.) [German] Ziel des Vorhabens war, im Sektor private Haushalte und Kleinverbrauch Bereiche zu identifizieren, in denen Verhaltensaenderungen zur Energieeinsparung fuehren koennen, und diese Potenziale fuer 1995, 2005 und 2020 zu quantifizieren. Darauf aufbauend waren Programme und Instrumente zur Umsetzung aufzuzeigen und zu bewerten. Gestuetzt auf Literaturrecherchen und Expertengespraeche wurden Einzelpotenziale, Rahmenbedingungen, Entwicklungstrends in der Technik und im Ausstattungsgrad ermittelt. Insgesamt koennten Verhaltensmassnahmen im Haushaltssektor die CO2-Emissionen im Basisjahr 1995 um 64 Mio, im Kleinverbrauch um 27 Mio t vermindern. Bis 2020 bleibt dieses Potenzial im Haushaltssektor in etwa gleich. Im Kleinverbrauch sinkt es infolge der autonomen Technikentwicklung auf 18 Mio t ab. Durch geeignete Programme koennen bis 2020 etwa 20-30% des Potenzials erreicht werden. (orig.)

Climate protection by reducing the emissions of greenhouse gases in households and the tertiary sector through climate-conscious behaviour. Vol. 1; Klimaschutz durch Minderung von Treibhausgasemissionen im Bereich Haushalte und Kleinverbrauch durch klimagerechtes Verhalten. Bd. 1. Private Haushalte

Energy Technology Data Exchange (ETDEWEB)

Brohmann, B; Cames, M

2000-06-01

The aim of the project was to identify areas in households and the tertiary sector in which changes in behaviour could result in energy conservation and thus a reduction of greenhouse gas emissions, and to quantify the potentials for 1995, 2005 and 2020. A second focus was on the analysis and evaluation of programmes and instruments to realise the potentials. With literature evaluation, expert interviews, and a household servey potentials and further technical development have been identified. In sum, behavioural measures can contribute to the CO2 reduction by 64 million tons in 1995 in households and 27 in the commercial sector in which the potential decreases to 18 million tons in 2020 due to the autonomous technical development. Adequate promotion programmes can help to realise 20-30% of the potential by 2020. (orig.) [German] Ziel des Vorhabens war, im Sektor private Haushalte und Kleinverbrauch Bereiche zu identifizieren, in denen Verhaltensaenderungen zur Energieeinsparung fuehren koennen, und diese Potenziale fuer 1995, 2005 und 2020 zu quantifizieren. Darauf aufbauend waren Programme und Instrumente zur Umsetzung aufzuzeigen und zu bewerten. Gestuetzt auf Literaturrecherchen und Expertengespraeche wurden Einzelpotenziale, Rahmenbedingungen, Entwicklungstrends in der Technik und im Ausstattungsgrad ermittelt. Insgesamt koennten Verhaltensmassnahmen im Haushaltssektor die CO2-Emissionen im Basisjahr 1995 um 64 Mio, im Kleinverbrauch um 27 Mio t vermindern. Bis 2020 bleibt dieses Potenzial im Haushaltssektor in etwa gleich. Im Kleinverbrauch sinkt es infolge der autonomen Technikentwicklung auf 18 Mio t ab. Durch geeignete Programme koennen bis 2020 etwa 20-30% des Potenzials erreicht werden. (orig.)

Declining Atmospheric pCO2 During the Late Miocene and Early Pliocene: New Insights from Paired Alkenone and Coccolith Stable Isotope Barometry

Science.gov (United States)

Phelps, S. R.; Polissar, P. J.; deMenocal, P. B.; Swann, J. P.; Guo, M. Y.; Stoll, H. M.

2015-12-01

806 combined with previous published measurements suggests atmospheric CO2 values declined across the late Miocene and early Pliocene. This decline is coincident with decreasing ocean temperatures suggesting the fundamental relationship between atmospheric CO2 and climate can qualitatively explain late Miocene warmth.

OECD's forskruede bistandsdefinition

DEFF Research Database (Denmark)

Fejerskov, Adam Moe

2014-01-01

Da en borgerlig regering i 2010 finansierede 300 mio. kroners ekstra asyludgifter over udviklingsbistanden, var det til stor vrede fra Socialdemokratiet. For få uger siden lagde selvsamme parti op til selvsamme manøvre, blot 8-9 gange større i volumen...

Histoire tertiaire de l'Arche de Brahmaputra ; son rôle dans la prospection des hydrocarbures du Haut Assam (Inde (résumé Tertiary History of Brahmaputra Arch. Its Role in Hydrocarbon Prospects of Upper Assam, India (Abstract

Directory of Open Access Journals (Sweden)

Murty K. N.

2006-10-01

sub-surface regional structure of the present Upper Assam Valley is a broad arch - Brahmaputra arch - parallel to and just a little south of Brahmaputra river, formed by two opposite tiltings: an initial palaeoslope towards south-east during Palaeocene-Oligocene and the other towards north-west during Mio-Pliocene. Two phases of migration of hydrocarbons con be recognised. The study enables assessment of future hydrocarbon prospects in Upper Assam. This arch has similar geological history as that of Bend-arch of north-central Texas and Huffon-Seminole-Ozark Arch of Oklahoma where rich pools have been found in nearby oil the rocks involved in the arching.

Impact of global SST gradients on the Mediterranean runoff changes across the Plio-Pleistocene transition

Science.gov (United States)

Colleoni, Florence; Cherchi, Annalisa; Masina, Simona; Brierley, Christopher M.

2015-06-01

This work explores the impact of the development of global meridional and zonal sea surface temperature (SST) gradients on the Mediterranean runoff variability during the Plio-Pleistocene transition, about 3 Ma. Results show that total annual mean Pliocene Mediterranean runoff is about 40% larger than during the preindustrial period due to more increased extratropical specific humidity. As a consequence of a weakened and extended Hadley cell, the Pliocene northwest Africa hydrological network produces a discharge 30 times larger than today. Our results support the conclusion that during the Pliocene, the Mediterranean water deficit was reduced relative to today due to a larger river discharge. By means of a stand-alone atmospheric general circulation model, we simulate the separate impact of extratropical and equatorial SST cooling on the Mediterranean runoff. While cooling the equatorial SST does not imply significant changes to the Pliocene Mediterranean hydrological budget, the extratropical SST cooling increases the water deficit due to a decrease in precipitation and runoff. Consequently, river discharge from this area reduces to preindustrial levels. The main teleconnections acting upon the Mediterranean area today, i.e., the North Atlantic Oscillation during winter and the "monsoon-desert" mechanism during summer already have a large influence on the climate of our Pliocene simulations. Finally, our results also suggest that in a climate state significantly warmer than today, changes of the Hadley circulation could potentially lead to increased water resources in northwest Africa.

Chimpanzee Food Preferences, Associative Learning, and the Origins of Cooking

Science.gov (United States)

Beran, Michael J.; Hopper, Lydia M.; de Waal, Frans B.M.; Sayers, Ken; Brosnan, Sarah F.

2015-01-01

A recent report suggested that chimpanzees demonstrate the cognitive capacities necessary to understand cooking (Warneken & Rosati, 2015). We offer alternate explanations and mechanisms that could account for the behavioral responses of those chimpanzees without invoking the understanding of cooking as a process. We discuss broader issues surrounding the use of chimpanzees in modeling hominid behavior and understanding aspects of human evolution. PMID:26659967

Chimpanzee Food Preferences, Associative Learning, and the Origins of Cooking

OpenAIRE

Beran, Michael J.; Hopper, Lydia M.; de Waal, Frans B.M.; Sayers, Ken; Brosnan, Sarah F.

2016-01-01

A recent report suggested that chimpanzees demonstrate the cognitive capacities necessary to understand cooking (Warneken & Rosati, 2015). We offer alternate explanations and mechanisms that could account for the behavioral responses of those chimpanzees without invoking the understanding of cooking as a process. We discuss broader issues surrounding the use of chimpanzees in modeling hominid behavior and understanding aspects of human evolution.

Chimpanzee food preferences, associative learning, and the origins of cooking.

Science.gov (United States)

Beran, Michael J; Hopper, Lydia M; de Waal, Frans B M; Sayers, Ken; Brosnan, Sarah F

2016-06-01

A recent report suggested that chimpanzees demonstrate the cognitive capacities necessary to understand cooking (Warneken & Rosati, 2015). We offer alternate explanations and mechanisms that could account for the behavioral responses of those chimpanzees, without invoking the understanding of cooking as a process. We discuss broader issues surrounding the use of chimpanzees in modeling hominid behavior and understanding aspects of human evolution.

Pliocene-Pleistocene lineage diversifications in the Eastern Indigo Snake (Drymarchon couperi) in the Southeastern United States.

Science.gov (United States)

Krysko, Kenneth L; Nuñez, Leroy P; Lippi, Catherine A; Smith, Daniel J; Granatosky, Michael C

2016-05-01

previously identified for other plants and animals, suggesting that these organisms might have shared a common evolutionary history related to historic sea level changes caused by Milankovitch cycles. Our estimated divergence times suggest that the most recent common ancestor (MRCA) between D. melanurus and southeastern United States Drymarchon occurred ca. 5.9Ma (95% HPD=2.5-9.8Ma; during the late Blancan of the Pleistocene through the Hemphillian of the Miocene), whereas the MRCA between the Atlantic and Gulf lineages in the southeastern United States occurred ca. 2.0Ma (95% HPD=0.7-3.7Ma; during the Irvingtonian of the Pleistocene through the Blancan of the Pliocene). During one or more glacial intervals within these times, these two lineages must have become separated and evolved independently. Despite numerous Milankovitch cycles along with associated forming of physical barriers (i.e., sea level fluctuations, high elevation sand ridges, clayey soils, and/or insufficient habitats) since their initial lineage diversification, these two lineages have likely come in and out of contact with each other many times, yet today they still illustrate near discrete geographic distributions. Although the Atlantic and Gulf lineages appear to be cryptic, a thorough study examining morphological characters should be conducted. We believe that our molecular data is crucial and should be incorporated in making conscious decisions in the management of a translocation program. We suggest that source populations for translocations include maintaining the integrity of the known genetic lineages found herein, as well as those coming from the closest areas that currently support sizable Drymarchon populations. Published by Elsevier Inc.

The Neogene lakes on the Balkan land

Directory of Open Access Journals (Sweden)

Krstić Nadežda

2012-01-01

Full Text Available Palaeogeographic maps of the lacustrine Miocene and Pliocene have been constructed according to all the known geological data. The Lakes of the Balkan Land, depending on the tectonics, migrated due to causes from the deep subsurface. There are several phases of the Miocene lakes: the lowermost Miocene transiting from marine Oligocene, Lower, Middle, Upper Miocene covering, in patches, the main part of the Land. The Pliocene lakes spread mostly to the north of the Balkan Land and covered only its marginal parts. Other lake-like sediments, in fact freshened parts of the Black Sea Kuialnician (Upper Pliocene, stretched along the middle and southern portions of the Balkan Peninsula (to the south of the Balkan Mt.. Subsequently, the Balkan Peninsula was formed.

Baboon feeding ecology informs the dietary niche of Paranthropus boisei.

Directory of Open Access Journals (Sweden)

Gabriele A Macho

Full Text Available Hominins are generally considered eclectic omnivores like baboons, but recent isotope studies call into question the generalist status of some hominins. Paranthropus boisei and Australopithecus bahrelghazali derived 75%-80% of their tissues' δ(13C from C4 sources, i.e. mainly low-quality foods like grasses and sedges. Here I consider the energetics of P. boisei and the nutritional value of C4 foods, taking into account scaling issues between the volume of food consumed and body mass, and P. boisei's food preference as inferred from dento-cranial morphology. Underlying the models are empirical data for Papio cynocephalus dietary ecology. Paranthropus boisei only needed to spend some 37%-42% of its daily feeding time (conservative estimate on C4 sources to meet 80% of its daily requirements of calories, and all its requirements for protein. The energetic requirements of 2-4 times the basal metabolic rate (BMR common to mammals could therefore have been met within a 6-hour feeding/foraging day. The findings highlight the high nutritional yield of many C4 foods eaten by baboons (and presumably hominins, explain the evolutionary success of P. boisei, and indicate that P. boisei was probably a generalist like other hominins. The diet proposed is consistent with the species' derived morphology and unique microwear textures. Finally, the results highlight the importance of baboon/hominin hand in food acquisition and preparation.

Palaeontological evidence for the last temporal occurrence of the ancient western Amazonian river outflow into the Caribbean.

Directory of Open Access Journals (Sweden)

Orangel Aguilera

Full Text Available Fossil catfishes from fluvio-lacustrine facies of late Miocene Urumaco, early Pliocene Castilletes and late Pliocene San Gregorio formations provide evidence of a hydrographic connection in what is today desert regions of northern Colombia and Venezuela. New discoveries and reevaluation of existing materials leads to the recognition of two new records of the pimelodid Brachyplatystoma cf. vaillantii, and of three distinct doradid taxa: Doraops sp., Rhinodoras sp., and an unidentified third form. The presence of fossil goliath long-whiskered catfishes and thorny catfishes are indicative of the persistence of a fluvial drainage system inflow into the South Caribbean during the Pliocene/Pleistocene boundary, complementary to the previous western Amazonian hydrographic system described from the Middle Miocene Villavieja Formation in central Colombia and Late Miocene Urumaco Formation in northwestern Venezuela. The Pliocene Castilletes and San Gregorio formations potentially represent the last lithostratigraphic units related with an ancient western Amazonian fish fauna and that drainage system in the Caribbean. Alternatively, it may preserve faunas from a smaller, peripheral river basin that was cut off earlier from the Amazon-Orinoco, today found in the Maracaibo basin and the Magdalena Rivers.

Mid-Piacensian mean annual sea surface temperature: an analysis for data-model comparisons

Science.gov (United States)

Dowsett, Harry J.; Robinson, Marci M.; Foley, Kevin M.; Stoll, Danielle K.

2010-01-01

Numerical models of the global climate system are the primary tools used to understand and project climate disruptions in the form of future global warming. The Pliocene has been identified as the closest, albeit imperfect, analog to climate conditions expected for the end of this century, making an independent data set of Pliocene conditions necessary for ground truthing model results. Because most climate model output is produced in the form ofmean annual conditions, we present a derivative of the USGS PRISM3 Global Climate Reconstruction which integrates multiple proxies of sea surface temperature (SST) into single surface temperature anomalies. We analyze temperature estimates from faunal and floral assemblage data,Mg/Ca values and alkenone unsaturation indices to arrive at a single mean annual SST anomaly (Pliocene minus modern) best describing each PRISM site, understanding that multiple proxies should not necessarily show concordance. The power of themultiple proxy approach lies within its diversity, as no two proxies measure the same environmental variable. This data set can be used to verify climate model output, to serve as a starting point for model inter-comparisons, and for quantifying uncertainty in Pliocene model prediction in perturbed physics ensembles.

Evolution of division of labor: emergence of different activities among group members.

Science.gov (United States)

Nakahashi, Wataru; Feldman, Marcus W

2014-05-07

The division of labor is an important component of the organization of human society. However, why this division evolved in hominids requires further investigation. Archeological evidence suggests that it appeared after the emergence of Homo sapiens and contributed to the great success of our species. We develop a mathematical model to investigate under what conditions division of labor should evolve. We assume two types of resources the acquisition of which demands different skills, and study the evolution of the strategy that an individual should use to divide its lifetime into learning and using each skill. We show that division of labor likely evolves when group size is large, skill learning is important for acquiring resources, and there is food sharing within a group. We also investigate division of labor by gender under the assumption that the genders have different efficiencies in acquiring each resource. We show that division of labor by gender likely evolves when skill learning is important and the difference in efficiencies between genders in acquiring resources is large. We discuss how the results of our analysis might apply to the evolution of division of labor in hominids. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stone tool function at the paleolithic sites of Starosele and Buran Kaya III, Crimea: behavioral implications.

Science.gov (United States)

Hardy, B L; Kay, M; Marks, A E; Monigal, K

2001-09-11

Stone tools are often the most abundant type of cultural remains at Paleolithic sites, yet their function is often poorly understood. Investigations of stone tool function, including microscopic use-wear and residue analyses, were performed on a sample of artifacts from the Paleolithic sites of Starosele (40,000-80,000 years BP) and Buran Kaya III (32,000-37,000 years BP). The Middle Paleolithic levels at Starosele exhibit a typical variant of the local Micoquian Industry. The artifacts from Buran Kaya III most closely resemble an Early Streletskayan Industry associated with the early Upper Paleolithic. The results of the functional analyses suggest that hominids at both sites were exploiting woody and starchy plant material as well as birds and mammals. Both sites show evidence of hafting of a wide variety of tools and the possible use of projectile or thrusting spears. These analyses were performed by using two different techniques conducted by independent researchers. Combined residue and use-wear analyses suggest that both the Upper Paleolithic and Middle Paleolithic hominids at these sites were broad-based foragers capable of exploiting a wide range of resources.

Anaerobic digestion in Denmark

DEFF Research Database (Denmark)

Angelidaki, Irini; Ellegaard, L.

2002-01-01

Centralized biogas plants (CBP) in Denmark codigest mainly manure, together with other organic waste such as industrial organic waste, source sorted household waste and sewage sludge. Today 22 large scale CBP's are in operation in Denmark and in 2001 they treated approx. 1.2 mio tonnes of manure ...

Industrial scale straw-to-biomethane conversion. A new bioenergy and business opportunity. Final report

Energy Technology Data Exchange (ETDEWEB)

Bonde, T.A. [BioFuel Technology ApS, Randers (Denmark); Sangaraju Raju, C.; Moeller, H.B. [Aarhus Univ., Forskningscenter Foulum, Tjele (Denmark); Slot Knudsen, M. [C.F. Nielsen A/S, Baelum (Denmark)

2013-09-01

The project resulted in the development, design, engineering, construction, and demonstration of a plant for industrial scale use of cereal straw for anaerobic digestion and production of biogas. The technology is based on the C. F. Nielsen A/S mechanical presses and adapted to the new purpose, to pre-treat and feed straw into a digester in one single step. A number of laboratory measurements as a function of variations of the pre-treatment showed, that under practical circumstances it is possible to achieve a biogas yield of 400 m{sup 3} per tons straw (corresponding to 300 m{sup 3} methane per tons volatile solids). The most significant effect was achieved by impregnating the straw with 1 % acetic acid before mechanical treatment. It was additionally shown that an extended incubation, after the mechanical treatment at 90 deg. C, resulted in a more pronounced effect than incubation at 140 deg. C. The maximum gas yield was 360 l methane per kg vs (volatile solids). This is equivalent to 290 l methane per kg straw (at 85 % dry matter, 95 % vs) or 450 l biogas per kg straw (at 65 % methane). A typical annual quantity of straw for anaerobic digestion would be 10.000 tons and more. A biogas plant digesting e.g. 100.000 tons liquid manure and 10.000 tons straw will produce a total of app. 6.5 mio. m{sup 3} biogas, of which 2.5 mio. m{sup 3} stems from the slurry and 4 mio. m{sup 3} from the straw. The result is a sustainable and robust biogas production and an equally sustainable economic performance of the biogas plant. (Author)

Cognitive cladistics and cultural override in Hominid spatial cognition

OpenAIRE

Haun, D.; Rapold, C.; Call, J.; Janzen, G.; Levinson, S.

2006-01-01

Current approaches to human cognition often take a strong nativist stance based on Western adult performance, backed up where possible by neonate and infant research and almost never by comparative research across the Hominidae. Recent research suggests considerable cross-cultural differences in cognitive strategies, including relational thinking, a domain where infant research is impossible because of lack of cognitive maturation. Here, we apply the same paradigm across children and adults o...

Cognitive cladistics and cultural override in Hominid spatial cognition

NARCIS (Netherlands)

Haun, D.B.M.; Rapold, C.J.; Call, J.; Janzen, G.; Levinson, S.C.

2006-01-01

Current approaches to human cognition often take a strong nativist stance based on Western adult performance, backed up where possible by neonate and infant research and almost never by comparative research across the Hominidae. Recent research suggests considerable cross-cultural differences in

Insights into hominid evolution from the gorilla genome sequence

Science.gov (United States)

Scally, Aylwyn; Dutheil, Julien Y.; Hillier, LaDeana W.; Jordan, Greg E.; Goodhead, Ian; Herrero, Javier; Hobolth, Asger; Lappalainen, Tuuli; Mailund, Thomas; Marques-Bonet, Tomas; McCarthy, Shane; Montgomery, Stephen H.; Schwalie, Petra C.; Tang, Y. Amy; Ward, Michelle C.; Xue, Yali; Yngvadottir, Bryndis; Alkan, Can; Andersen, Lars N.; Ayub, Qasim; Ball, Edward V.; Beal, Kathryn; Bradley, Brenda J.; Chen, Yuan; Clee, Chris M.; Fitzgerald, Stephen; Graves, Tina A.; Gu, Yong; Heath, Paul; Heger, Andreas; Karakoc, Emre; Kolb-Kokocinski, Anja; Laird, Gavin K.; Lunter, Gerton; Meader, Stephen; Mort, Matthew; Mullikin, James C.; Munch, Kasper; O’Connor, Timothy D.; Phillips, Andrew D.; Prado-Martinez, Javier; Rogers, Anthony S.; Sajjadian, Saba; Schmidt, Dominic; Shaw, Katy; Simpson, Jared T.; Stenson, Peter D.; Turner, Daniel J.; Vigilant, Linda; Vilella, Albert J.; Whitener, Weldon; Zhu, Baoli; Cooper, David N.; de Jong, Pieter; Dermitzakis, Emmanouil T.; Eichler, Evan E.; Flicek, Paul; Goldman, Nick; Mundy, Nicholas I.; Ning, Zemin; Odom, Duncan T.; Ponting, Chris P.; Quail, Michael A.; Ryder, Oliver A.; Searle, Stephen M.; Warren, Wesley C.; Wilson, Richard K.; Schierup, Mikkel H.; Rogers, Jane; Tyler-Smith, Chris; Durbin, Richard

2012-01-01

Summary Gorillas are humans’ closest living relatives after chimpanzees, and are of comparable importance for the study of human origins and evolution. Here we present the assembly and analysis of a genome sequence for the western lowland gorilla, and compare the whole genomes of all extant great ape genera. We propose a synthesis of genetic and fossil evidence consistent with placing the human-chimpanzee and human-chimpanzee-gorilla speciation events at approximately 6 and 10 million years ago (Mya). In 30% of the genome, gorilla is closer to human or chimpanzee than the latter are to each other; this is rarer around coding genes, indicating pervasive selection throughout great ape evolution, and has functional consequences in gene expression. A comparison of protein coding genes reveals approximately 500 genes showing accelerated evolution on each of the gorilla, human and chimpanzee lineages, and evidence for parallel acceleration, particularly of genes involved in hearing. We also compare the western and eastern gorilla species, estimating an average sequence divergence time 1.75 million years ago, but with evidence for more recent genetic exchange and a population bottleneck in the eastern species. The use of the genome sequence in these and future analyses will promote a deeper understanding of great ape biology and evolution. PMID:22398555

Burial and thermal history simulation of the Abu Rudeis-Sidri oil field, Gulf of Suez-Egypt: A 1D basin modeling study

Science.gov (United States)

Awadalla, Ahmed; Hegab, Omar A.; Ahmed, Mohammed A.; Hassan, Saad

2018-02-01

An integrated 1D model on seven wells has been performed to simulate the multi-tectonic phases and multiple thermal regimes in the Abu Rudeis-Sidri oilfield. Concordance between measured and calculated present-day temperatures is achieved with present-day heat flows in the range of 42-55 mW/m2. Reconstruction of the thermal and burial histories provides information on the paleotemperature profiles, the timing of thermal activation as well as the effect of the Oligo-Miocene rifting phases and its associated magmatic activity. The burial histories show the pre-rift subsidence was progressive but modest, whereas the syn-rift was more rapid (contemporaneous with the main rifting phases and basin formation). Finally, the early post-rift thermal subsidence was slow to moderate in contrast to the late post-rift thermal subsidence which was moderate to rapid. The simulated paleo heat flow illustrates a steady state for the pre-rift phase and non-steady state (transient) for syn-rift and postrift phases. Three geothermal regimes are recognized, each of which is associated with a specific geological domain. 1) A lower geothermal regime reflects the impact of stable tectonics (pre-rift). 2) The higher temperature distribution reflects the syn-rift high depositional rate as well as the impact of stretching and thinning (rifting phases) of the lithosphere. 3) A local higher geothermal pulse owing to the magmatic activity during the Oligo-Miocene time (ARM-1 and Sidri-7 wells). Paleoheat flow values of 100mW/m2 (Oligo-Miocene rifting phase) increased to 120mW/m2 (Miocene rifting phase) and lesser magnitude of 80mW/m2 (Mio- Pliocene reactivation phase) have been specified. These affected the thermal regime and temperature distribution by causing perturbations in subsurface temperatures. A decline in the background value of 60mW/m2 owing to conductive cooling has been assigned. The blanketing effect caused by low thermal conductivity of the basin-fill sediments has been simulated

Preliminary results of chronostratigraphic field work, OSL-dating and morphogenetic reconstruction of an alluvial apron at Alborz southern foothill, Damghan basin, Iran

Science.gov (United States)

Büdel, Christian; Fuchs, Markus; Majid Padashi, Seyed; Baumhauer, Roland

2014-05-01

Here we present preliminary results of a chronostratigraphic study of an alluvial fan in the Damghan Basin, northern Iran. The basin sediments date back to the Mio- and Pliocene and therefore represent the starting point of alluvial fan aggradation. Today, the still active alluvial fans prograde from the Albors Mountain ranges and sit on the older sediment bodies. In this study, our focus is on the late Pleistocene to Holocene alluvial fan sedimentation history. The upper stratigraphy of the alluvial fans and intercalated lake deposits is characterized by six individual layers of gravels and fines, representing six different stratigraphic units. These units are described and classified by detailed geomorphological and stratigraphic mapping. To establish an alluvial fan chronology, six profiles were sampled for OSL dating. As expected, due to the high-energy transport system of alluvial fan aggradation in semi-desert environments, OSL dating of these sediments is challenging due to the problem of insufficient bleaching. Consequently, most of the samples are interpreted as maximum ages. However, the measurements show a consistent internal age structure and the overall OSL-based chronology is in agreement with the age model derived from our geomorphological analysis. As a first interpretation, based on surveyed geomorphological features and chronological analysis, we could identify seven morphodynamic phases, leading to a genetic model of alluvial fan aggradation. The oldest Pleistocene age estimate is derived from a former lake terrace. The following ages represent ongoing lake sediment deposition and the development of a proximal and mid-fan gravel cover. After the youngest lake deposits were accumulated within the Holocene, the lake starts to retreat and small alluvial fans are filling up the former lake bottom. This last sedimentation phase can be divided in at least two sub-phases, probably coupled to a lateral shifting of the active depositional lobe and to the

East African Cenozoic vegetation history.

Science.gov (United States)

Linder, Hans Peter

2017-11-01

The modern vegetation of East Africa is a complex mosaic of rainforest patches; small islands of tropic-alpine vegetation; extensive savannas, ranging from almost pure grassland to wooded savannas; thickets; and montane grassland and forest. Here I trace the evolution of these vegetation types through the Cenozoic. Paleogene East Africa was most likely geomorphologically subdued and, as the few Eocene fossil sites suggest, a woodland in a seasonal climate. Woodland rather than rainforest may well have been the regional vegetation. Mountain building started with the Oligocene trap lava flows in Ethiopia, on which rainforest developed, with little evidence of grass and none of montane forests. The uplift of the East African Plateau took place during the middle Miocene. Fossil sites indicate the presence of rainforest, montane forest and thicket, and wooded grassland, often in close juxtaposition, from 17 to 10 Ma. By 10 Ma, marine deposits indicate extensive grassland in the region and isotope analysis indicates that this was a C 3 grassland. In the later Miocene rifting, first of the western Albertine Rift and then of the eastern Gregory Rift, added to the complexity of the environment. The building of the high strato-volcanos during the later Mio-Pliocene added environments suitable for tropic-alpine vegetation. During this time, the C 3 grassland was replaced by C 4 savannas, although overall the extent of grassland was reduced from the mid-Miocene high to the current low level. Lake-level fluctuations during the Quaternary indicate substantial variation in rainfall, presumably as a result of movements in the intertropical convergence zone and the Congo air boundary, but the impact of these fluctuations on the vegetation is still speculative. I argue that, overall, there was an increase in the complexity of East African vegetation complexity during the Neogene, largely as a result of orogeny. The impact of Quaternary climatic fluctuation is still poorly understood

Etude épidémio-clinique des diarrhées aiguës à rotavirus chez les nourrissons à l'hôpital Jason Sendwe de Lubumbashi, République Démocratique du Congo

Science.gov (United States)

Sangaji, Maguy Kabuya; Mukuku, Olivier; Mutombo, Augustin Mulangu; Mawaw, Paul Makan; Swana, Edouard Kawawa; Kabulo, Benjamin Kasongo; Mutombo, André Kabamba; Wembonyama, Stanis Okitotsho; Luboya, Oscar Numbi

2015-01-01

Introduction Le rotavirus est un problème de santé publique, non seulement dans les pays en développement où tous les enfants sont infectés avant l’âge de deux à trois ans mais aussi dans les pays développés où les conditions d'hygiène sont bonnes. La présente étude est la première à fournir des informations sur la prévalence de l'infection à rotavirus dans les diarrhées aiguës des nourrissons dans la ville de Lubumbashi. Elle s'est fixée comme objectifs de déterminer la fréquence hospitalière ainsi que la saisonnalité, les caractéristiques sociodémographiques, cliniques et évolutives de l'infection à Rotavirus chez les nourrissons admis à l'hôpital Jason Sendwe de Lubumbashi pour une diarrhée aiguë. Méthodes Il s'agit d'une étude descriptive et transversale menée pendant la période allant du 1er janvier au 31 décembre 2012. Les paramètres épidémio-cliniques et évolutifs (âge, sexe, saison, signes cliniques, nombre journalier de selles et évolution) des enfants diagnostiqués positifs au rotavirus ont été comparés à ceux des enfants dont le test au rotavirus était négatif. Le degré de signification était de 5%. Résultats Nous avons récolté 193 cas de diarrhées aiguës dont 104 nourrissons étaient infectés par le rotavirus soit 53,8%. Des taux élevés des diarrhées à rotavirus sont enregistrés au cours de la saison sèche comparativement à la saison des pluies (p0,05). Par ailleurs, les enfants infectés par le rotavirus étaient 6 fois plus susceptibles de présenter une déshydratation modérée/sévère (p0,05). Conclusion Le rotavirus est confirmé dans la ville de Lubumbashi et touche souvent les enfants d’âge ≤12 mois, pendant la saison sèche sans distinction de sexe et conduit rapidement à une déshydratation modérée/sévère. Une prise en charge adaptée et précoce permet d’éviter les décès et l'assainissement du milieu, le lavage des mains, la prise d'eau potable et la

Dial-A-Decon Solution Chemistry GAP Testing

Science.gov (United States)

2012-04-01

M25, Ml00, M250 , Ml000). The pipette size used was determined by the amount of extraction solution to be delivered. The analytical GC vials used...dilutions were prepared using Gilson Microman positive displacement pipettes (Gilson product numbers MIO, M25, Ml00, M250 , Ml000). The pipette size

ARC: A camcopter based mine field detection system

NARCIS (Netherlands)

Schutte, K.; Sahli, H.; Schrottmayer, D.; Eisl, M.; Varas, F.J.; Bajic, M.; Uppsall, M.; Breejen, E. den

2001-01-01

The area affected with antipersonnel land mines in 56 infested countries is estimated to be 1 Mio km. This represents a serious threat to the human lives and a major obstacle for the development of the polluted region. The objective of ARC is to develop, demonstrate and promote a new system for

Maternal death and the Millennium Development Goals

DEFF Research Database (Denmark)

Rasch, Vibeke

2007-01-01

Maternal health is one of the main global health challenges and reduction of the maternal mortality ratio, from the present 0.6 mio. per year, by three-quarters by 2015 is the target for the fifth Millennium Development Goal (MDG 5). However this goal is the one towards which the least progress h...