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Sample records for permian chase group

  1. Geology of the Pennsylvanian and Permian Culter Group and Permian Kaibab Limestone in the Paradox Basin, southeastern Utah and southwestern Colorado

    Science.gov (United States)

    Condon, Steven M.

    1997-01-01

    The Cutler Formation is composed of thick, arkosic, alluvial sandstones shed southwestward from the Uncompahgre highlands into the Paradox Basin. Salt tectonism played an important role in deposition of the Cutler in some areas. In the northeast part of the basin, more than 8,000 ft, and as much as 15,000 ft, of arkose was trapped between rising salt anticlines - this arkose is thin to absent over the crests of some anticlines. In the western and southern parts of the basin, the Cutler is recognized as a Group consisting of, in ascending order: the lower Cutler beds, Cedar Mesa Sandstone, Organ Rock Formation, White Rim Sandstone, and De Chelly Sandstone. The aggregate thickness of these formations is less than 2,000 ft. The formations of the Cutler Group were deposited in a complex system of alluvial, eolian, and marine environments characterized by abrupt vertical and lateral lithologic changes. The basal Cutler is Pennsylvanian in age, but the bulk of the Group was deposited during the Permian. The Cutler is conformably underlain by the Pennsylvanian Hermosa Group across most of the basin. It is overlain unconformably by the Permian Kaibab Limestone in the western part of the Paradox Basin. The Cutler or Kaibab are overlain unconformably by the Triassic Moenkopi or Chinle Formations.

  2. Tornado Chasing.

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    Faidley, Warren

    1991-01-01

    Presents the rationale and purposes behind the phenomenon known as storm chasing, as well as the contributions that tornado chasers have made to both scientific knowledge and public safety. Provides statistical information on tornado frequencies and locations and contact addresses for storm chasers. (JJK)

  3. Permian plants from the Chutani Formation (Titicaca Group, Northern Altiplano of Bolivia: II. The morphogenus Glossopteris

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    Roberto Iannuzzi

    2004-03-01

    Full Text Available Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group, near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia. This paper presents the first description of specimens of the morphogenus Glossopteris from Bolivia. The Bolivian specimens of Glossopteris consist of poorly-preserved impressions, although they present the diagnostic features of this morphogenus. They are fragments of leaves with secondary veins of taeniopterid-type, typical of glossopterids from Late Permian deposits of Gondwana. The only species of Pecopteris confirmed in the first part of this study, i.e. P. dolianitii Rösler and Rohn (see Vieira et al. 2004, was previously reported from the Late Permian beds of the Rio do Rasto and Estrada Nova formations in the Paraná Basin (southern Brazil. Therefore, a Late Permian age is proposed for the fossil plant-bearing beds of the Chutani Formation based on the analyzed assemblage. The phytogeographic implications of this new find are briefly analyzed.Plantas fósseis, pertencentes aos morfo-gêneros Glossopteris, Pecopteris e Asterotheca, foram coletadas na porção superior da seção aflorante da Formação Chutani, próxima ao povoado de San Pablo de Tiquina, sudeste do lago Titicaca (Altiplano norte, Bolívia. Este trabalho apresenta a primeira descrição de espécimes do morfo-gênero Glossopteris provenientes da Bolívia. Os espécimes estudados de Glossopteris consistem em impressões foliares pobremente preservadas nas quais feições diagnósticas estão presentes. Os fragmentos foliares apresentam venação secundária do tipo teniopteróide, uma característica típica de glossopterídeas encontradas em depósitos do Permiano Superior do Gondwana. Por sua vez, a única espécie de Pecopteris confirmada para estes níveis da Formação Chutani, i.e. P. dolianitii

  4. Revisiting platinum group elements of Late Permian coals from western Guizhou Province, SW China

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Liang [State Key Lab of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550002 (China); Gao, Jianfeng [Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR (China)

    2008-08-05

    Twenty five coal samples from the Late Permian coal-bearing strata in Weining, Nayong, and Zhijin, western Guizhou Province, SW, China, were analyzed for platinum group elements (PGEs). The coal ashes were digested by the Carius tube technique and accurately measured by isotope dilution-inductively coupled plasma mass spectrometry (ID-ICP-MS) for all PGEs. The results are much lower than the previous reported values. Our study suggested that the previously reported PGE values are incorrect and may due to the polyatomic interferences in ICP-MS measurements. In our study, samples from the Weining coalfield have the lowest PGE contents (from 0.019 Ir to 0.42 ng/g Pd), which represent the PGE background value in coal in western Guizhou province. Some of the coals have Pt and Pd contents about 20-times higher than the background value, indicating PGEs are concentrated. We also reported new and reliable PGE data and background value of coal in western Guizhou province, SW, China, and suggested to rework the PGE background values of Chinese coals. (author)

  5. Carbon isotope variations in the upper Carboniferous - Permian Mallemuk Mountain Group, eastern North Greenland

    International Nuclear Information System (INIS)

    Stemmerik, L.; Magaritz, M.

    1989-01-01

    Isotope data from Late Palaeozoic limestones of the Wandel Sea Basin in eastern North Greenland show a variation of δ 13 C from 0.0 0/00 to 5.7 0/00 vs PDB. Carbonates depleted in 13 C occur in the basal part of lower Moscovian, upper Moscovian and middle Gzhelian transgressive sequences. 13 C enriched limestones occur later in the cycles. The most 13 C enriched limestones occur in the youngest (late Early Permian-early Late Permian) part of the sequence in Amdrup Land. The isotopic data is believed to represent changes in the global carbon cycle. Thus 13 C enriched carbonates correlate to periods of burial of organic carbon mostly as coal, while 13 C depleted carbonates formed as the result of erosion and oxidation of organic carbon during sea-level low stands. (author)

  6. A new stem group echinoid from the Triassic of China leads to a revised macroevolutionary history of echinoids during the end-Permian mass extinction

    Science.gov (United States)

    Thompson, Jeffrey R.; Hu, Shi-xue; Zhang, Qi-Yue; Petsios, Elizabeth; Cotton, Laura J.; Huang, Jin-Yuan; Zhou, Chang-yong; Wen, Wen; Bottjer, David J.

    2018-01-01

    The Permian-Triassic bottleneck has long been thought to have drastically altered the course of echinoid evolution, with the extinction of the entire echinoid stem group having taken place during the end-Permian mass extinction. The Early Triassic fossil record of echinoids is, however, sparse, and new fossils are paving the way for a revised interpretation of the evolutionary history of echinoids during the Permian-Triassic crisis and Early Mesozoic. A new species of echinoid, Yunnanechinus luopingensis n. sp. recovered from the Middle Triassic (Anisian) Luoping Biota fossil Lagerstätte of South China, displays morphologies that are not characteristic of the echinoid crown group. We have used phylogenetic analyses to further demonstrate that Yunnanechinus is not a member of the echinoid crown group. Thus a clade of stem group echinoids survived into the Middle Triassic, enduring the global crisis that characterized the end-Permian and Early Triassic. Therefore, stem group echinoids did not go extinct during the Palaeozoic, as previously thought, and appear to have coexisted with the echinoid crown group for at least 23 million years. Stem group echinoids thus exhibited the Lazarus effect during the latest Permian and Early Triassic, while crown group echinoids did not.

  7. Coal forming conditions for coal seams and coal measures of the Heshan Group Upper Permian Series in Guangxi Province (part 1)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.

    1980-10-01

    Coal forming conditions for the coal measures of the Heshan Group are discussed based on the analysis of the historical background and paleogeographical environment of the Permian in Guangxi Province. The roof, floor, and partings of the seams are composed of algal micritic limestone, therefore affirming that the central part of Guangxi Province in the late Permian was a typical epi-continental sea. The compensative deposit of algea on the carbonate platform in very shallow water created the conditions for the occurrence of the peat swamp and established the supra-tidal swampy facies. The environment for the accumulation of the major coal seams are analyzed. (In Chinese)

  8. Permian ultrafelsic A-type granite from Besar Islands group, Johor, peninsular Malaysia

    Science.gov (United States)

    Ghani, Azman A.; Hazad, Fatin Izzani; Jamil, Azmiah; Xiang, Quek Long; Atiqah Wan Ismail, Wan Nur; Chung, Sun-Lin; Lai, Yu-Ming; Roselee, Muhammad Hatta; Islami, Nur; Nyein, Kyaw Kyaw; Amir Hassan, Meor Hakif; Abu Bakar, Mohd Farid; Umor, Mohd Rozi

    2014-12-01

    The granitic rocks of the peninsula have traditionally been divided into two provinces, i.e., Western and Eastern provinces, corresponding to S- and I-type granite respectively. The Western Province granite is characterised by megacrystic and coarse-grained biotite, tin-mineralised, continental collision granite, whereas, the Eastern Province granite is bimodal I-type dominated by granodiorite and associated gabbroic of arc type granite. This paper reports the occurrence of an A-type granite from peninsular Malaysia. The rocks occur in the Besar, Tengah, and Hujung islands located in the southeastern part of the peninsula. The granite is highly felsic with SiO2 ranging from 75.70% to 77.90% (differentiation index = 94.2-97.04). It is weakly peraluminous (average ACNK =1.02), has normative hypersthene (0.09-2.19%) and high alkali content (8.32-8.60%). The granites have many A-type characteristics, among them are shallow level of emplacement, high Ga, FeT/MgO and low P, Sr, Ti, CaO and Nb. Calculated zircon saturation temperatures for the Besar magma ranging from 793 ∘ to 806 ∘C is consistent with high temperature partial melting of a felsic infracrustal source which is taken as one of the mechanisms to produce A-type magma. The occurrence of the A-type granite can be related to the extensional back arc basin in the Indo-China terrane during the earliest Permian.

  9. Refining the chronostratigraphy of the Karoo Basin, South Africa: magnetostratigraphic constraints support an early Permian age for the Ecca Group

    Science.gov (United States)

    Belica, Mercedes E.; Tohver, Eric; Poyatos-Moré, Miquel; Flint, Stephen; Parra-Avila, Luis A.; Lanci, Luca; Denyszyn, Steven; Pisarevsky, Sergei A.

    2017-12-01

    The Beaufort Group of the Karoo Basin, South Africa provides an important chrono- and biostratigraphic record of vertebrate turnovers that have been attributed to the end-Permian mass extinction events at ca. 252 and 260 Ma. However, an unresolved controversy exists over the age of the Beaufort Group due to a large data set of published U-Pb SHRIMP (Sensitive High Resolution Ion Microprobe) zircon results that indicate a ca. 274-250 Ma age range for deposition of the underlying Ecca Group. This age range requires the application of a highly diachronous sedimentation model to the Karoo Basin stratigraphy and is not supported by published palaeontologic and palynologic data. This study tested the strength of these U-Pb isotopic data sets using a magnetostratigraphic approach. Here, we present a composite ∼1500 m section through a large part of the Ecca Group from the Tanqua depocentre, located in the southwestern segment of the Karoo Basin. After the removal of two normal polarity overprints, a likely primary magnetic signal was isolated at temperatures above 450 °C. This section is restricted to a reverse polarity, indicating that it formed during the Kiaman Reverse Superchron (ca. 318-265 Ma), a distinctive magnetostratigraphic marker for early-middle Permian rocks. The Ecca Group has a corresponding palaeomagnetic pole at 40.8°S, 77.4°E (A95 = 5.5°). U-Pb SHRIMP ages on zircons are presented here for comparison with prior isotopic studies of the Ecca Group. A weighted mean U-Pb age of 269.5 ± 1.2 Ma was determined from a volcanic ash bed located in the uppermost Tierberg Formation sampled from the O + R1 research core. The age is interpreted here as a minimum constraint due to a proposed Pb-loss event that has likely influenced a number of published results. A comparison with the Geomagnetic Polarity Time Scale as well as published U-Pb TIMS ages from the overlying Beaufort Group supports a ca. 290-265 Ma age for deposition of the Ecca Group.

  10. Loss-Chasing, Alexithymia and Impulsivity: Alexithymia as a precursor to loss-chasing when gambling.

    Directory of Open Access Journals (Sweden)

    Peter Anthony Bibby

    2016-01-01

    Full Text Available Objective: To examine the relationship between loss-chasing, the propensity to continue gambling to recover from losses, alexithymia, a personality trait associated poor emotional processing and impulsivity, the tendency to act quickly without reflection or consideration of the consequences.Method: Two experiments are reported (E1: N=60, Males, 11; Age, 21.6 years. E2: N=49, Males, 22; Age, 21.1 years. In experiment 1, two groups (low alexithymia, high alexithymia completed the Cambridge Gambling Task. Loss-chasing behaviour was investigated. In experiment 2, both alexithymia (low, high and impulsivity (low, high were examined also using the CGT. A further change was the order of bet proportion from ascending to descending. Results: Experiment 1 shows loss-chasing behaviour in participants high in alexithymia but not those low in alexithymia (η_p^2=.09. Experiment 2 shows loss-chasing behaviour in participants both low and high in alexithymia but it was greater for participants high in alexithymia (η_p^2=.09. The effect of impulsivity was not statistically significant (η_p^2=.01. Loss-chasing behaviour was correlated with the emotional facets of alexithymia but not the cognitive facet. Conclusions: Alexithymia is a precursor to loss-chasing when gambling and loss-chasing reflects the cognitive and emotional aspects of gambling. Specifically, the tendency to loss-chase depends on the need to recoup previous losses and failure to process the emotional consequences of those losses.

  11. Paleomagnetic and magnetostratigraphic investigations of the whitehorse group/quartermaster (Dewey Lake) formation (upper permian-lowermost triassic) in the Palo Duro basin, northwest Texas, USA

    Science.gov (United States)

    Collins, Dylan R.

    In northwest Texas, upper Permian to lowermost Triassic hematite-cemented detrital sedimentary rocks, which include a small number of regionally extensive ash beds, were deposited during the time interval of the greatest mass extinction event sequences in Earth history. The magnetic polarity stratigraphy, as well as key rock magnetic properties, of the upper Whitehorse Group (WH) and Quartermaster formations (QM) at selected sections in the Palo Duro Basin, have been determined using thermal, and chemical demagnetization approaches and anisotropy of magnetic susceptibility, acquisition of isothermal remanent magnetization (IRM) and backfield demagnetization, and thermal demagnetization of three component IRM methods. Demagnetization results show that the WH/QM contains a primary/near-primary characteristic remanent magnetization at each level sampled and thus the magnetic polarity stratigraphy for each section can be compared with existing polarity time scales across the Permian-Triassic boundary. Estimated site mean directions yield a paleomagnetic pole for the latest Permian for North America of 57.8°N, 130.6°E from 38 sampled sites.

  12. Permian plants from the Chutani Formation (Titicaca Group, Northern Altiplano of Bolivia: I. Genera Pecopteris and Asterotheca

    Directory of Open Access Journals (Sweden)

    Carlos E. L. Vieira

    2004-03-01

    Full Text Available Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group, near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia. Here we report the analysis of fern-type foliage found at this location. Three species of pecopterid fronds are identified: Pecopteris dolianitii Rohn and Rösler, P. cf. P. cadeadensis Rohn and Rösler, and P. cf. P. pedrasica Read. All these species are typically found in Permian deposits of the Paraná Basin in southern Brazil. Despite the poor preservation of the material, a fertile specimen could be studied and was determined as Asterotheca sp. The paleoenvironmental and paleoecological implications of this new find are briefly analyzed.Plantas fósseis, pertencentes aos morfo-gêneros Glossopteris, Pecopteris e Asterotheca, foram coletadas na porção superior da seção aflorante da Formação Chutani, próxima ao povoado de San Pablo de Tiquina, sudeste do lago Titicaca (Altiplano norte, Bolívia. Este trabalho analisa folhagens do tipo feto encontradas neste sítio. Entre os espécimes estéreis, três espécies de frondes pecopterídeas foram identificadas: Pecopteris dolianiti, P. cf. cadeadensis e P. cf. pedrasica. Todas essas espécies eram até agora restritas aos depósitos permianos da Bacia do Paraná. A despeito do estado de preservação ruim do material, um espécime fértil pôde ser determinado como pertencente ao gênero Asterotheca. Implicações paleoambientais e paleoecológicas deste novo achado são brevemente analisadas.

  13. Shale Gas characteristics of Permian black shales (Ecca group, Eastern Cape, South Africa)

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    Geel, Claire; Booth, Peter; Schulz, Hans-Martin; Horsfield, Brian; de Wit, Maarten

    2013-04-01

    This study involves a comprehensive and detailed lithological, sedimentalogical, structural and geochemical description of the lower Ecca Group in the Eastern Cape, South Africa. The Ecca group hosts a ~ 245 million year old organic-rich black shale, which has recently been the focus of interest of petroleum companies worldwide. The shale was deposited under anoxic conditions in a setting which formed as a consequence of retro-arc foreland basin development related to the Cape Fold Belt. This sedimentary/tectonic environment provided the conditions for deeply buried black shales to reach maturity levels for development in the gas window. The investigation site is called the Greystone Area and is situated north of Wolwefontein en route to Jansenville. The area has outcrops of the Dwyka, the Ecca and the lower Beaufort Groups. The outcrops were mapped extensively and the data was used in conjunction with GIS software to produce a detailed geological map. North-south cross sections were drawn to give indication of bed thicknesses and formation depths. Using the field work, data two boreholes were accurately sited on the northern limb of a shallow easterly plunging syncline. The first borehole reached 100m and the second was drilled to 292m depth (100m percussion and 192m core). The second borehole was drilled 200m south of the first, to penetrate the formations at a greater depth and to avoid surface weathering. Fresh core from the upper Dwyka Group, the Prince Albert Formation, the Whitehill Formation, Collingham Formation and part of the Ripon Formation were successfully extracted and a detailed stratigraphic log has been drawn up. The core was sampled during extraction and the samples were immediately sent to the GFZ in Potsdam, Germany, for geochemical analyses. As suspected the black shales of the the Whitehill Formation are high in organic carbon and have an average TOC value of 4.5%, whereas the Prince Albert and Collingham Formation are below 1%. Tmax values

  14. Chasing as a model of psychogenic stress: characterization of physiological and behavioral responses.

    Science.gov (United States)

    Lee, Ji-Hye; Kimm, Sunwhi; Han, Jung-Soo; Choi, June-Seek

    2018-03-25

    Being chased by a predator or a dominant conspecific can induce significant stress. However, only a limited number of laboratory studies have employed chasing by itself as a stressor. In this study, we developed a novel stress paradigm in which rats were chased by a fast-moving object in an inescapable maze. In Experiment 1, defensive behaviors and stress hormone changes induced by chasing stress were measured. During the chasing stress, the chasing-stress group (n = 9) froze and emitted 22-kHz ultrasonic vocalizations (USVs), but the no-chasing control group (n = 10) did not. Plasma corticosterone levels significantly increased following the chasing and were comparable to those of the restraint-stress group (n = 6). In Experiment 2, the long-lasting memory of the chasing event was tested after three weeks. The chasing-stress group (n = 15) showed higher levels of freezing and USV than the no-chasing group (n = 14) when they were presented with the tone associated with the object's chasing action. Subsequently, the rats were subjected to Pavlovian threat conditioning with a tone as a conditioned stimulus and footshock as an unconditioned stimulus. The chasing-stress group showed higher levels of freezing and USV during the conditioning session than the no-chasing group, indicating sensitized defensive reactions in a different threat situation. Taken together, the current results suggest that chasing stress can induce long-lasting memory and sensitization of defensive responses to a new aversive event as well as immediate, significant stress responses.

  15. Paleomagnetism and Magnetostratigraphy of Upper Permian to Lower Triassic (?) Beaufort Group Strata at Bethulie, Karoo Basin, Free State Province, South Africa

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    Geissman, J. W.; Gastaldo, R. A.; Neveling, J.; Makubalo, S.

    2017-12-01

    A multifaceted approach to understand the timing of interpreted environmental changes during the Late Permian to possibly Early Triassic (?) time in the Beaufort Group strata of the Karoo Basin includes work to establish robust magnetic polarity records for sections previously interpreted to encompass end-Permian extinction events. Demonstrating the preservation of an early-acquired remanence (RM) in Karoo strata is required for a robust magnetostratigraphy. Yet, this is challenging due to thermochemical effects related to the Early Jurassic (ca. 183 Ma) Karoo Large Igneous Province (LIP), and the NE to SW increase in burial diagenesis attending Cape Fold Belt tectonism. Documentation of a primary RM in these strata, which appears to be preserved in some areas, requires careful laboratory- and field-based assessment. We report data from 53 sites collected at the well-studied Bethulie section, Free State Province, in which several samples per individual horizon to assess ChRM uniformity. Strata well-removed from dikes yield both normal and reverse polarity ChRM. It is always the case that the first-removed RM is a NNW seeking, moderate to steep negative-inclination ChRM (normal polarity); NRM intensities are typically 1 to 5 mA/m. Sites BT15 and BT21, which are located in strata lying some 4 m below the often-cited "event bed" interval inferred to be the terrestrial expression of the Permian/Triassic boundary, is dominated by a well-defined reverse RM with a normal overprint RM unblocked below 400oC, implying elevated temperatures (i.e., 100 to 250oC+) for ca. 1 Ma (+/-). Contact tests are positive but complicated. Host strata collected in distances equal to or less than 1-2 dike widths from the intrusions have been thermally remagnetized and demonstrate high NRM intensities (> 50 mA/m). Collectively, we interpret these data to indicate that any ChRM, with the exception of those from host strata in baked contacts, that persists above Tlub of 425oC is pre-Karoo LIP

  16. Permian of Southeast Asia: an overview

    Science.gov (United States)

    Fontaine, Henri

    2002-08-01

    Permian rocks are widely distributed throughout Southeast Asia. Because of the tropical-equatorial climate the rocks are commonly deeply weathered and covered by dense vegetation over much of the region. Elsewhere, Permian rocks are well exposed and easy to access, particularly where limestone outcrops have weathered to form spectacular, castellated, tower karst. Many limestone outcrops, containing abundant fusulinaceans, were early recognized to be of Permian age, but many outcrops without fusulinaceans, erroneously assigned to the Permian, were found subsequently to be of Triassic age, and more careful studies have established the Permian age of rocks of other lithologies. It is now recognized that different depositional environments are represented by the Permian deposits in various parts of the region. Massive limestones, widespread throughout the region, represent extensive carbonate platforms; local occurrences of thick bedded cherts indicate deposition in deep marine environments, coal, bauxite and clastic sediments with vertebrate remains in North Vietnam and Laos indicate deposition in a continental environment, and pebbly mudstones in Myanmar, Peninsular Thailand, northwest Malaysia and Sumatra, are considered to have been formed in a glacial environment. Volcanic rocks are absent in northwest Peninsular Malaysia and Peninsular Thailand, but are extensively developed in North Vietnam, Sumatra, the eastern Malay Peninsula and Timor. Fossils, representing many fossil groups, are often prolific in Permian sediments, with fusulinaceans, for example, occurring in astronomical numbers in many limestone outcrops. Age-diagnostic fossils demonstrate that the whole of the Permian is represented in different areas of Southeast Asia. Fossil faunal and floral assemblages have been used to establish climatic conditions and environments of deposition, to define distinct crustal blocks and to provide the basis for reconstructing the palaeogeography during Permian times.

  17. Assessing the role of detrital zircon sorting on provenance interpretations in an ancient fluvial system using paleohydraulics - Permian Cutler Group, Paradox Basin, Utah and Colorado

    Science.gov (United States)

    Findlay, C. P., III; Ewing, R. C.; Perez, N. D.

    2017-12-01

    Detrital zircon age signatures used in provenance studies are assumed to be representative of entire catchments from which the sediment was derived, but the extent to which hydraulic sorting can bias provenance interpretations is poorly constrained. Sediment and mineral sorting occurs with changes in hydraulic conditions driven by both allogenic and autogenic processes. Zircon is sorted from less dense minerals due to the difference in density, and any age dependence on zircon size could potentially bias provenance interpretations. In this study, a coupled paleohydraulic and geochemical provenance approach is used to identify changes in paleohydraulic conditions and relate them to spatial variations in provenance signatures from samples collected along an approximately time-correlative source-to-sink pathway in the Permian Cutler Group of the Paradox Basin. Samples proximal to the uplift have a paleoflow direction to the southwest. In the medial basin, paleocurrent direction indicates salt movement caused fluvial pathways divert to the north and northwest on the flanks of anticlines. Channel depth, flow velocity, and discharge calculations were derived from field measurements of grain size and dune and bar cross-stratification indicate that competency of the fluvial system decreased from proximal to the medial basin by up to a factor of 12. Based upon the paleohydraulic calculations, zircon size fractionation would occur along the transect such that the larger zircons are removed from the system prior to reaching the medial basin. Analysis of the size and age distribution of zircons from the proximal and distal fluvial system of the Cutler Group tests if this hydraulic sorting affects the expected Uncompahgre Uplift age distribution.

  18. Extinguishing a Permian World

    NARCIS (Netherlands)

    Schneebeli-Hermann, E.

    2012-01-01

    At the end of the Permian, ca. 252 Ma ago, marine and terrestrial fauna were facing the most extensive mass extinction in Earth history (Raup and Sepkoski, 1982). 80%–95% of all species on Earth, on land and in the oceans, became extinct (Benton et al., 2004) within an estimated time interval of

  19. Fold superimposition in the Permian groups in the central Beishan orogenic collage (northwestern China): highlights for the late evolution of the Altaids

    Science.gov (United States)

    Zhonghua, Tian; Wenjiao, Xiao; Yehua, Shan

    2013-04-01

    The southernmost part of the Central Asian Orogenic Belt (CAOB) or Altaids (Sengör and Burtman, 1993; Xiao et al., 2009), a rare and magnificent example of mesoscopic fold superimposition, involving the Permian sandstone, slightly to mildly metamorphosed clastic rocks, is well exposed in the central Beishan Orogenic Collage (BOC). We provide a detailed description of the morphological features of this phenomenon, based on an enormous amount of structural data collected during recent twice field mapping in the study area. Two phases of folds are readily distinguishable both in satellite image (Fig.la) and our own field map (Fig.1b). Fold is tight to close, N-S-trending in the first phase (F1), and open and E-W-trending in the second phase (F2). The first phase upright folds were refolded into a smaller number of (F2), whose axial planes and axes are vertical or subvertical. They plunge gentle to moderately in the former and moderately to steeply in the latter. Their interference is in general categorized as Ramsay's (Ramsay, 1967) type 2 or Ghosh's third/fourth mode based on the value of initial tightness. However, from east to west there exists a slight variation of a zigzag to crescent to mushroom interference pattern. This subtle variation corresponds with the westward increases of the F2 interlimb angle and of the percentage of coarse-grain clastic rocks, suggesting its dependence upon the F2 deformation and the lithology. Axial slaty cleavages (S1) and associated dip-slip slickensides are more abundant in the first phase. Cleavages and strike-slip slickensides related to the seconding refolding are also occurred in the area. Finally, according to the petrological, geochemical and geochronological data, we conclude that the deformation history of the superposed folds were associated with the late evolution in the BOC. In the late Permian, the fold superimposition occurred in sedimentary rocks deposited in a Permian back-arc basin. The basin was intensely

  20. Paleomagnetic results from Late Pennsylvanian marls and Early Permian red paleosols of the Dunkard group, Ohio and West Virginia, U.S.A.

    Science.gov (United States)

    Abrajevitch, A.; Oliva, B.; Peters, S.; Beehr, A.; van der Voo, R.

    2006-12-01

    Sediments of the Dunkard Gr. were deposited in the Appalachian foreland basin during the Pennsylvanian and Early Permian, an interval encompassing the long reverse polarity Kiaman chron. Lithofacies in the Dunkard Gr. in eastern Ohio and western West Virginia include lenticular and sheet-form cross-bedded micaceous sandstones, coal, mottled red and purple mudstones, gray laminated mudstones and argillaceous lime mudstones. They are indicative of deposition on a low-gradient, tropical wet-dry fluvial plain. Few lithofacies are laterally persistent over sufficiently long distances, so that correlation schemes are based largely on coal horizons, partly for historical economic reasons and partly because coal beds appear to be more laterally persistent than most other lithofacies. Magnetostratigraphy would therefore provide a powerful additional correlation tool in the Dunkard Gr, A short normal polarity interval has been reported in the Dunkard Gr. (Helsley, 1965), but to date such a change in magnetic field polarity has not been confirmed by later studies. To confirm the presence of the normal polarity subchron and to explore the possibility of using it as a correlation tool in the Dunkard Gr., we sampled 5 sections thought to straddle the Late Pennyslvanian-Early Permian boundary. Sampled lithofacies include red and mottled red-purple paleosols, grey mudstones containing siderite concretions, micaceous sandstones, and dark gray argillaceous limestones. Samples were demagnetized thermally and by AF. The remanent magnetic directions agree with those expected for the Early Permian. A change in polarity was detected in three of the studied sections. Magnetization is carried by several different magnetic minerals, mostly hematite in paleosols and iron sulfides in combination with magnetite in sandstones, marls and limestones. Although we have found good evidence for the normal polarity interval within Kiaman age rocks of the Dunkard Gr., additional magnetostratigraphic

  1. Permian potentiometric analysis

    International Nuclear Information System (INIS)

    Devary, J.L.

    1983-09-01

    Pacific Northwest Laboratory (PNL) was requested to analyze potentiometric data from the Wolfcamp Formation of the Permian System to evaluate the recommendations by the University of Texas/Bureau of Economic Geology (UT/BEG) that additional geohydrologic boreholes be drilled into the Wolfcamp. The UT/BEG recommended that two stratigraphic and two geohydrologic borings be drilled into the Permian System during FY83 and that several shallow hydrologic tests be made in the Dockum Formation. A geostatistical technique known as kriging was applied to objectively evaluate these geohydrologic borehole recommendations. The Deaf Smith County location appears to be an excellent choice for a borehole. No high quality potentiometric data are available from Deaf Smith County and a borehole location immediately upgradient from the candidate repository site is needed. Adding this borehole location to the potentiometric data base will significantly reduce field data uncertainty near the location being studied. The Swisher County location does not appear to be the best choice. High quality data values H2206 and H2360 are located immediately upgradient from the proposed repository site. The best placement of additional geohydrological boreholes in the Wolfcamp Formation depends strongly upon the proposed repository location. The variability of the potentiometric data causes estimation errors to rapidly increase away from locations of field measurements. Suggested locations for additional boreholes for the Deaf Smith investigations are in northwest Randall or central Potter Counties. Ideal borehole locations for the Swisher county studies appear to be in southeast Randall and Armstrong Counties

  2. Avidin chase can reduce myelotoxicity associated with radioimmunotherapy of experimental liver micrometastases in mice

    International Nuclear Information System (INIS)

    Sato, Noriko; Saga, Tsuneo; Sakahara, Harumi; Nakamoto, Yuji; Zhao, Songji; Iida, Yasuhiko; Konishi, Junji; Kuroki, Masahide; Endo, Keigo

    2000-01-01

    Myelotoxicity is the main factor which decides the maximum tolerated dose (MTD) in radioimmunotherapy (RIT). Since bone marrow is mostly irradiated from blood radioactivity, enhancing the clearance of unbound circulating radiolabeled antibody is important to reduce myelotoxicity and to increase the MTD. We applied the avidin chase method, which was devised to obtain high tumor-to-background ratios in tumor-targeting, to RIT of experimental liver micrometastases and evaluated its influence on the side effects and therapeutic outcome. Seven days after intrasplenic injection of human colon cancer LS174T cells, nude mice were intravenously injected with biotinylated 131 I-labeled anti-CEA monoclonal antibody (MAb) (24-38 μg, 11.1 MBq). Mice of the chase group then received an intravenous injection of avidin twice (24 and 30 h, 72-115 μg each). Biodistribution, side effects (white blood cell counts and body weight change), and short- and long-term therapeutic effects were determined. Avidin chase markedly accelerated the clearance of radiolabeled MAb from the blood (P<0.0001) and normal tissues, resulting in milder leukocytopenia and body weight loss, both of which recovered earlier than in the non-chase group (P<0.01). The tumor uptake of radiolabeled MAb was also decreased by avidin chase, but the metastases-to-background ratios were increased. Avidin chase gave the therapeutic gain ratio of 1.89. Treated groups with and without avidin chase showed significant therapeutic effects compared to the non-treated group. There was no significant difference in the therapeutic effects between the two treated groups. Avidin chase effectively reduced the side effects of RIT and should increase the MTD. (author)

  3. Fox Chase Network: Fox Chase Cancer Center's community hospital affiliation program.

    Science.gov (United States)

    Higman, S A; McKay, F J; Engstrom, P F; O'Grady, M A; Young, R C

    2000-01-01

    Fox Chase Cancer Center developed a format for affiliation with community providers in 1986. Fox Chase Network was formed to establish hospital-based community cancer centers to increase access to patients involved in clinical research. Under this program, the Fox Chase Network now contributes 500 patients per year to prevention and clinical research studies. As relationships with community providers form, patient referrals have increased at Fox Chase Cancer Center and for each Fox Chase Network member. A dedicated staff is required to operate the central office on a day-to-day basis as well as at each affiliate. We have found this to be a critical element in each program's success. New challenges in the cancer business-increasing volumes with declining revenue-have caused us to reconfigure the services offered to affiliates, while maintaining true to our mission: to reduce the burden of human cancer.

  4. Chinese Learning Journeys: Chasing the Dream

    Science.gov (United States)

    Su, Feng, Ed.

    2011-01-01

    Eight students from mainland China chart their learning journeys across national and continental boundaries and socio-cultural contexts. The five women and three men structure their experiences of studying in China and the West around the turning points and life changing choices they made in chasing their dreams. They embody its emergent…

  5. Pattern production through a chiral chasing mechanism

    Science.gov (United States)

    Woolley, Thomas E.

    2017-09-01

    Recent experiments on zebrafish pigmentation suggests that their typical black and white striped skin pattern is made up of a number of interacting chromatophore families. Specifically, two of these cell families have been shown to interact through a nonlocal chasing mechanism, which has previously been modeled using integro-differential equations. We extend this framework to include the experimentally observed fact that the cells often exhibit chiral movement, in that the cells chase, and run away, at angles different to the line connecting their centers. This framework is simplified through the use of multiple small limits leading to a coupled set of partial differential equations which are amenable to Fourier analysis. This analysis results in the production of dispersion relations and necessary conditions for a patterning instability to occur. Beyond the theoretical development and the production of new pattern planiforms we are able to corroborate the experimental hypothesis that the global pigmentation patterns can be dependent on the chirality of the chromatophores.

  6. Physicochemical analysis of Permian coprolites from Brazil

    Science.gov (United States)

    Rodrigues, M. I. C.; da Silva, J. H.; Santos, F. Eroni P.; Dentzien-Dias, P.; Cisneros, J. C.; de Menezes, A. S.; Freire, P. T. C.; Viana, B. C.

    2018-01-01

    In this paper we performed the study of two coprolites (fossilized feces) collected from the exposed levels of the Pedra de Fogo Formation, Parnaiba Sedimentary Basin, and Rio do Rasto Formation, Paraná Sedimentary Basin, both of the Palaeozoic era (Permian age). They were characterized using X-ray diffractometry, infrared, Raman and energy dispersive spectroscopy techniques in order to aid our understanding of the processes of fossilization and to discuss issues related to the feeding habits of the animals which generated those coprolites, probably cartilaginous fishes. The results obtained using a multitechnique approach showed that although these coprolites are from different geological formations, 3000 km away from each other, they show the same major crystalline phases and elemental composition. The main phases found were hydroxyapatite, silica, calcite and hematite, which lead to infer that those coprolites were formed under similar conditions and produced by a similar group of carnivore or omnivore fishes.

  7. A Factor Increasing Venous Contamination on Bolus Chase Three-dimensional Magnetic Resonance Imaging: Charcot Neuroarthropathy.

    Science.gov (United States)

    Çildağ, Mehmet B; Ertuğrul, Mustafa B; Köseoğlu, Ömer Fk; Armstrong, David G

    2018-01-01

    The study aimed to evaluate the ratio of venous contamination in diabetic cases without foot lesion, with foot lesion and with Charcot neuroarthropathy (CN). Bolus-chase three-dimensional magnetic resonance (MR) of 396 extremities of patients with diabetes mellitus was analyzed, retrospectively. Extremities were divided into three groups as follows: diabetic patients without foot ulcer or Charcot arthropathy (Group A), patients with diabetic foot ulcers (Group B) and patients with CN accompanying diabetic foot ulcers (Group C). Furthermore, amount of venous contamination classified as no venous contamination, mild venous contamination, and severe venous contamination. The relationship between venous contamination and extremity groups was investigated. Severe venous contamination was seen in Group A, Group B, and Group C, 5.6%, 15.2%, and 34.1%, respectively. Statistically significant difference was seen between groups with regard to venous contamination. Venous contamination following bolus chase MR was higher in patients with CN.

  8. A factor increasing venous contamination on bolus chase three-dimensional magnetic resonance imaging: Charcot neuroarthropathy

    Directory of Open Access Journals (Sweden)

    Mehmet B Cildag

    2018-01-01

    Full Text Available Background: The study aimed to evaluate the ratio of venous contamination in diabetic cases without foot lesion, with foot lesion and with Charcot neuroarthropathy (CN. Materials and Methods: Bolus-chase three-dimensional magnetic resonance (MR of 396 extremities of patients with diabetes mellitus was analyzed, retrospectively. Extremities were divided into three groups as follows: diabetic patients without foot ulcer or Charcot arthropathy (Group A, patients with diabetic foot ulcers (Group B and patients with CN accompanying diabetic foot ulcers (Group C. Furthermore, amount of venous contamination classified as no venous contamination, mild venous contamination, and severe venous contamination. The relationship between venous contamination and extremity groups was investigated. Results: Severe venous contamination was seen in Group A, Group B, and Group C, 5.6%, 15.2%, and 34.1%, respectively. Statistically significant difference was seen between groups with regard to venous contamination. Conclusion: Venous contamination following bolus chase MR was higher in patients with CN.

  9. Whirling in the late Permian: ancestral Gyrinidae show early radiation of beetles before Permian-Triassic mass extinction.

    Science.gov (United States)

    Yan, Evgeny V; Beutel, Rolf G; Lawrence, John F

    2018-03-16

    Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic "Great Dying" - Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic "tip-dating" analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the "modern" lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place

  10. Permian of Southeast Asia: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Fontaine, H.

    2002-07-01

    Permian rocks are widely distributed throughout Southeast Asia. Because of the tropical-equatorial climate the rocks are commonly deeply weathered and covered by dense vegetation over much of the region. Elsewhere, Permian rocks are well exposed and easy to access, particularly where limestone outcrops have weathered to form spectacular, castellated, tower karst. Many limestone outcrops, containing abundant fusulinaceans, were recognized early on to be of Permian age, but many outcrops without fusulinaceans, erroneously assigned to the Permian, were found subsequently to be of Triassic age, and more careful studies have established the Permian age of rocks of other lithologies. Different depositional environments are represented by the Permian deposits in various parts of the region. Massive limestones, throughout the region represent extensive carbonate platforms; local occurrences of thick bedded cherts indicate deposition in deep marine environments, coal, bauxite and clastic sediments with vertebrate remains in North Vietnam and Laos indicate deposition in a continental environment, and pebbly mudstones in Myanmar, Peninsular Thailand, northwest Malaysia and Sumatra, are considered to have been formed in a glacial environment. Volcanic rocks are not found in northwest Peninsular Malaysia and Peninsular Thailand, but are extensively developed in North Vietnam, Sumatra, the eastern Malay Peninsula and Timor. Fossils are often prolific in Permian sediments, with fusulinaceans, for example, occurring in large numbers in many limestone outcrops. Age-diagnostic fossils demonstrate that the whole of the Permian is represented in different areas of Southeast Asia. Fossil faunal and floral assemblages have been used to establish climatic conditions and environments of deposition, to define distinct crustal blocks and to provide the basis for reconstructing the palaeogeography during Permian times.

  11. Feasibility study of heavy oil recovery in the Permian Basin (Texas and New Mexico)

    International Nuclear Information System (INIS)

    Olsen, D.K.; Johnson, W.I.

    1993-05-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production. Each report covers select areas of the United States. The Permian Basin of West Texas and Southeastern New Mexico is made up of the Midland, Delaware, Val Verde, and Kerr Basins; the Northwestern, Eastern, and Southern shelves; the Central Basin Platform, and the Sheffield Channel. The present day Permian Basin was one sedimentary basin until uplift and subsidence occurred during Pennsylvanian and early Permian Age to create the configuration of the basins, shelves, and platform of today. The basin has been a major light oil producing area served by an extensive pipeline network connected to refineries designed to process light sweet and limited sour crude oil. Limited resources of heavy oil (10'' to 20'' API gravity) occurs in both carbonate and sandstone reservoirs of Permian and Cretaceous Age. The largest cumulative heavy oil production comes from fluvial sandstones of the Cretaceous Trinity Group. Permian heavy oil is principally paraffinic and thus commands a higher price than asphaltic California heavy oil. Heavy oil in deeper reservoirs has solution gas and low viscosity and thus can be produced by primary and by waterflooding. Because of the nature of the resource, the Permian Basin should not be considered a major heavy oil producing area

  12. Paper Chase and the Socratic Method of Teaching Law.

    Science.gov (United States)

    Dillon, J. T.

    1980-01-01

    It is argued that the Socratic method of teaching law as depicted in the book, movie, and TV series "Paper Chase" is not really the Socratic method at all. The genuine Socratic method and the questioning technique used in "Paper Chase" are examined and their appropriateness and effectiveness as methods for teaching contract law…

  13. The application of DSA bolus chase technology in diagnosing the vascular disorders of lower extremities due to diabetes mellitus

    International Nuclear Information System (INIS)

    Ren Chongyang; Di Zhenhai; Mao Xuequn; Zou Rong; Zhang Jian; Wang Meirong; Li Quan

    2010-01-01

    Objective: To retrospectively evaluate the digital subtraction angiography (DSA) bolus chase technology in diagnosing the vascular disorders of lower extremities due to diabetes mellitus. Methods: From January 2004 to March 2010, DSA was performed in forty-five diabetes patients with suspicious vascular diseases of lower extremities. Among them, 24 cases (31 lower limbs)were examined with DSA bolus chase technology and the remaining 21 cases (21 lower limbs)were examined with traditional segmentational technique. The contrast dosage used in angiography, the total exposure time, the examination time and the imaging value for making diagnosis were analyzed and compared between two techniques. Results: For DSA bolus chase technology group, the contrast dosage used in angiography, the total exposure time and the examination time were 25.26 ml, 13.23 s and 37.26 min, respectively,with an average exposure of 101.65 pictures. For traditional segmentational technique group, the contrast dosage used in angiography, the total exposure time and the examination time were 130.00 ml, 52.38 s and 50.48 min, respectively, with an average exposure of 118.33 pictures. The percentage of high quality images in bolus chase technology group and in traditional segmentational technique group were 90.3% and 90.5%, respectively. All the images could meet the requirements for making a reliable diagnosis. Conclusion: Digital subtraction angiography by using bolus-chase technology can well demonstrate the vascular pathology of lower extremities caused by diabetes mellitus, obtain sufficient imaging information necessary for making a reliable diagnosis. DSA bolus chase technology is superior to traditional segmentational technique in shortening procedure time, reducing contrast medium dosage and decreasing radiation dose. (authors)

  14. Toxic leucoencephalopathy after 'chasing the dragon'.

    Science.gov (United States)

    Singh, Rajinder; Saini, Monica

    2015-06-01

    Toxic leucoencephalopathy (TLE) is a rare neurological complication of heroin abuse. 'Chasing the dragon' is an inhalational mode of heroin abuse that originated in Southeast Asia. Intriguingly, no cases of TLE have been reported from this region, although the inhalational mode of heroin abuse is common. We herein report the case of a middle-aged man with a history of polysubstance abuse who presented with progressive neurological symptoms and progressed to an uncommunicative state. While the initial impression was that of iatrogenic parkinsonism, diffuse leucoencephalopathy with sparing of the cerebellum was noted on magnetic resonance imaging. In view of his history of inhalational heroin abuse close to the onset of the neurological symptoms, a diagnosis of TLE was made. No clinical improvement was noted with administration of a dopaminergic agent. This is the first known case of delayed TLE following heroin inhalation from Southeast Asia with the unusual feature of cerebellar sparing.

  15. Chases and escapes the mathematics of pursuit and evasion

    CERN Document Server

    Nahin, Paul J

    2012-01-01

    We all played tag when we were kids. What most of us don't realize is that this simple chase game is in fact an application of pursuit theory, and that the same principles of games like tag, dodgeball, and hide-and-seek are also at play in military strategy, high-seas chases by the Coast Guard, and even romantic pursuits. In Chases and Escapes, Paul Nahin gives us the first complete history of this fascinating area of mathematics, from its classical analytical beginnings to the present day. Drawing on game theory, geometry, linear algebra, target-tracking algorithms, and much

  16. Structure of the Anayet Permian basin (Axial Zone, Central Pyrenees)

    Science.gov (United States)

    Rodriguez, L.; Cuevas, J.; Tubía, J. M.

    2012-04-01

    The Anayet Permian basin was generated by strike-slip tectonics that opened subsident basins with pull-apart geometries in the western Spanish Axial Zone (between the Aragon and Tena valleys). A continental succession of Permian age, that represents the first post-variscan deposits in the area, fills the basin and covers discordantly Devonian to Carboniferous limestones, sandstones and slates. Permian deposits have been classically divided in four main detrital groups, with three basic volcanic episodes interbedded (Gisbert, 1984, Bixel, 1987): the Grey Unit (50-120 m, Estefanian to Kungurian) with slates, conglomerates, tobaceous slates, coal and pyroclastic deposits, the Transition Unit (50 m maximum) showing grey and red sandstones and lutites with oolitic limestones intercalated, the Lower Red Unit (250 m) composed of cross-bedded red sandstones and andesitic volcanic rocks at the top, and finally the Upper Red Unit (400 m minimum, top eroded) formed by three fining up megasequences of carbonates, red sandstones and lutites with lacustrine carbonates intercalated and alkali basalts at the top. Increasingly older rocks are found towards the western part of the basin, where its depocenter is located. South-vergent angular folds deform the Permian sedimentary succession. Fold axes are N115 °E-trending, almost horizontal and are characterized by a remarkably constant orientation. Folds exhibit a long limb dipping slightly to the north and a short vertical limb, occasionally reversed. In the Anayet basin four main folds, with a wavelength of 400 m, can be distinguished, two anticlines and two synclines, with minor folds associated. Related to the angular folds an axial plane foliation, E-trending and dipping 40 to 60° to the north, is developed in the lutites. The more competent rocks, conglomerates and breccias, only locally show a spaced fracture cleavage. No main thrusts have been detected in Permian rocks. However, minor scale decollements, usually low angle

  17. Prolonged Permian Triassic ecological crisis recorded by molluscan dominance in Late Permian offshore assemblages.

    Science.gov (United States)

    Clapham, Matthew E; Bottjer, David J

    2007-08-07

    The end-Permian mass extinction was the largest biotic crisis in the history of animal life, eliminating as many as 95% of all species and dramatically altering the ecological structure of marine communities. Although the causes of this pronounced ecosystem shift have been widely debated, the broad consensus based on inferences from global taxonomic diversity patterns suggests that the shift from abundant brachiopods to dominant molluscs was abrupt and largely driven by the catastrophic effects of the end-Permian mass extinction. Here we analyze relative abundance counts of >33,000 fossil individuals from 24 silicified Middle and Late Permian paleocommunities, documenting a substantial ecological shift to numerical dominance by molluscs in the Late Permian, before the major taxonomic shift at the end-Permian mass extinction. This ecological change was coincident with the development of fluctuating anoxic conditions in deep marine basins, suggesting that numerical dominance by more tolerant molluscs may have been driven by variably stressful environmental conditions. Recognition of substantial ecological deterioration in the Late Permian also implies that the end-Permian extinction was the climax of a protracted environmental crisis. Although the Late Permian shift to molluscan dominance was a pronounced ecological change, quantitative counts of 847 Carboniferous-Cretaceous collections from the Paleobiology Database indicate that it was only the first stage in a stepwise transition that culminated with the final shift to molluscan dominance in the Late Jurassic. Therefore, the ecological transition from brachiopods to bivalves was more protracted and complex than their simple Permian-Triassic switch in diversity.

  18. Establishment of the Fox Chase Network Breast Cancer Risk Registry

    National Research Council Canada - National Science Library

    Daly, Mary

    1997-01-01

    .... The development of the Fox Chase Cancer Center Breast Cancer Risk Registry was proposed to facilitate research in the epidemiologic and genetic predictors of disease and will permit evaluation...

  19. SWFSC/MMTD/ETP: Chase Encirclement Stress Studies (CHESS) 2001

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The CHase Encirclement Stress Studies (CHESS) are part of a comprehensive research program designed to investigate the status of dolphin stocks that are involved in...

  20. Episodic chasing in pathological gamblers using the Iowa gambling task

    DEFF Research Database (Denmark)

    Linnet, J.; Rojskjaer, S.; Nygaard, Jørgen

    2006-01-01

    NPGs on the Iowa Gambling Task (IGT) and the Zuckerman Sensation Seeking Scale (SSS). The PGs showed significantly more chasing and had significantly poorer decision-making strategies than NPGs, particularly among males (F = 4.52, p

  1. Knowing When to Stop: The Brain Mechanisms of Chasing Losses

    DEFF Research Database (Denmark)

    Campbell-Meiklejohn, Daniel; Woolrich, Mark; Passingham, Dick

    2008-01-01

    adult participants decided to chase losses or decided to quit gambling to prevent further losses.ResultsChasing losses was associated with increased activity in cortical areas linked to incentive-motivation and an expectation of reward. By contrast, quitting was associated with decreased activity...... in pathological gambling might involve a failure to appropriately balance activity within neural systems coding conflicting motivational states. Similar mechanisms might underlie the loss-of-control over appetitive behaviors in other impulse control disorders....

  2. The Upper Permian in the Netherlands

    NARCIS (Netherlands)

    Visser, W.A.

    1955-01-01

    The Upper Permian in the Netherlands, as known from borehole data, is deposited in a mainly evaporitic facies north of the Brabant and Rhenish Massifs. In the extreme south (Belgian Campine, de Peel) a near-shore facies of reef dolomites and elastics occurs. In the western and central Netherlands

  3. Permian macro- and miofloral diversity, palynodating and ...

    Indian Academy of Sciences (India)

    The order Glossopteridales is highly diversi- fied with 23 taxa and the genus Glossopteris, with 22 species, dominates the flora. The mioflora of this colliery is represented by two distinct palynoassemblages. The palynoassemblage-III is correlatable with the palynoflora of Early Permian (Artinskian) Lower Barakar Formation.

  4. The CHASE laboratory search for chameleon dark energy

    International Nuclear Information System (INIS)

    Steffen, Jason H.

    2010-01-01

    A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. We present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys.

  5. The CHASE laboratory search for chameleon dark energy

    Energy Technology Data Exchange (ETDEWEB)

    Steffen, Jason [Fermi National Accelerator Laboratory - Fermilab, P.O. Box 500, Batavia, IL 60510-5011 (United States)

    2010-07-01

    A scalar field is a favorite candidate for the particle responsible for dark energy. However, few theoretical means exist that can simultaneously explain the observed acceleration of the Universe and evade tests of gravity. The chameleon mechanism, whereby the properties of a particle depend upon the local environment, is one possible avenue. I present the results of the Chameleon Afterglow Search (CHASE) experiment, a laboratory probe for chameleon dark energy. CHASE marks a significant improvement over other searches for chameleons both in terms of its sensitivity to the photon/chameleon coupling as well as its sensitivity to the classes of chameleon dark energy models and standard power-law models. Since chameleon dark energy is virtually indistinguishable from a cosmological constant, CHASE tests dark energy models in a manner not accessible to astronomical surveys. (author)

  6. The terminal Permian in European Russia: Vyaznikovian Horizon, Nedubrovo Member, and Permian-Triassic boundary

    Science.gov (United States)

    Lozovsky, V. R.; Balabanov, Yu. P.; Karasev, E. V.; Novikov, I. V.; Ponomarenko, A. G.; Yaroshenko, O. P.

    2016-07-01

    The comprehensive analysis of the data obtained on terrestrial vertebrata, ostracods, entomologic fauna, megaflora, and microflora in deposits of the Vyaznikovian Horizon and Nedubrovo Member, as well as the paleomagnetic data measured in enclosing rocks, confirms heterogeneity of these deposits. Accordingly, it is necessary to distinguish these two stratons in the terminal Permian of the East European Platform. The combined sequence of Triassic-Permian boundary deposits in the Moscow Syneclise, which is considered to be the most complete sequence in the East European Platform, is as follows (from bottom upward): Vyatkian deposits; Vyaznikovian Horizon, including Sokovka and Zhukovo members; Nedubrovo Member (Upper Permian); Astashikha and Ryabi members of the Vokhmian Horizon (Lower Triassic). None of the sequences of Permian-Triassic boundary deposits known in the area of study characterizes this sequence in full volume. In the north, the Triassic deposits are underlain by the Nedubrovo Member; in the south (the Klyazma River basin), the sections are underlain by the Vyaznikovian Horizon. The Permian-Triassic boundary adopted in the General Stratigraphic Scale of Russia for continental deposits of the East European platform (the lower boundary of the Astashikha Member) is more ancient than the one adopted in the International Stratigraphic Chart. The same geological situation is observed in the German Basin and other localities where Triassic continental deposits are developed. The ways of solving this problem are discussed in this article.

  7. Exploratory shaft facility preliminary designs - Permian Basin

    International Nuclear Information System (INIS)

    1983-09-01

    The purpose of the Preliminary Design Report, Permian Basin, is to provide a description of the preliminary design for an Exploratory Shaft Facility in the Permian Basin, Texas. This issue of the report describes the preliminary design for constructing the exploratory shaft using the Large Hole Drilling method of construction and outlines the preliminary design and estimates of probable construction cost. The Preliminary Design Report is prepared to complement and summarize other documents that comprise the design at the preliminary stage of completion, December 1982. Other design documents include drawings, cost estimates and schedules. The preliminary design drawing package, which includes the construction schedule drawing, depicts the descriptions in this report. For reference, a list of the drawing titles and corresponding numbers are included in the Appendix. The report is divided into three principal sections: Design Basis, Facility Description, and Construction Cost Estimate. 30 references, 13 tables

  8. 75 FR 31510 - Fox Chase Bancorp, Inc., Hatboro, PA; Approval of Conversion

    Science.gov (United States)

    2010-06-03

    ... DEPARTMENT OF THE TREASURY Office of Thrift Supervision [AC-43: OTS No. H-4707] Fox Chase Bancorp, Inc., Hatboro, PA; Approval of Conversion Application Notice is hereby given that on May 14, 2010, the Office of Thrift Supervision approved the application of Fox Chase MHC and Fox Chase Bank, Hatboro...

  9. An application of importance-performance analysis to recreational storm chasing

    Science.gov (United States)

    Jiawen Chen; Sonja Wilhelm Stanis; Carla Barbieri; Shuangyu. Xu

    2012-01-01

    Since the release of the movie "Twister" in 1996, storm chasing has become an increasingly popular form of recreation. Storm chasing tour agencies have emerged to provide technical assistance and guidance to individuals wishing to participate in this activity. However, little is known about the participants' perceptions of their storm chasing tours....

  10. Microbialites and global environmental change across the Permian-Triassic boundary: a synthesis.

    Science.gov (United States)

    Kershaw, S; Crasquin, S; Li, Y; Collin, P-Y; Forel, M-B; Mu, X; Baud, A; Wang, Y; Xie, S; Maurer, F; Guo, L

    2012-01-01

    Permian-Triassic boundary microbialites (PTBMs) are thin (0.05-15 m) carbonates formed after the end-Permian mass extinction. They comprise Renalcis-group calcimicrobes, microbially mediated micrite, presumed inorganic micrite, calcite cement (some may be microbially influenced) and shelly faunas. PTBMs are abundant in low-latitude shallow-marine carbonate shelves in central Tethyan continents but are rare in higher latitudes, likely inhibited by clastic supply on Pangaea margins. PTBMs occupied broadly similar environments to Late Permian reefs in Tethys, but extended into deeper waters. Late Permian reefs are also rich in microbes (and cements), so post-extinction seawater carbonate saturation was likely similar to the Late Permian. However, PTBMs lack widespread abundant inorganic carbonate cement fans, so a previous interpretation that anoxic bicarbonate-rich water upwelled to rapidly increase carbonate saturation of shallow seawater, post-extinction, is problematic. Preliminary pyrite framboid evidence shows anoxia in PTBM facies, but interbedded shelly faunas indicate oxygenated water, perhaps there was short-term pulsing of normally saturated anoxic water from the oxygen-minimum zone to surface waters. In Tethys, PTBMs show geographic variations: (i) in south China, PTBMs are mostly thrombolites in open shelf settings, largely recrystallised, with remnant structure of Renalcis-group calcimicrobes; (ii) in south Turkey, in shallow waters, stromatolites and thrombolites, lacking calcimicrobes, are interbedded, likely depth-controlled; and (iii) in the Middle East, especially Iran, stromatolites and thrombolites (calcimicrobes uncommon) occur in different sites on open shelves, where controls are unclear. Thus, PTBMs were under more complex control than previously portrayed, with local facies control playing a significant role in their structure and composition. © 2011 Blackwell Publishing Ltd.

  11. Global taxonomic diversity of anomodonts (tetrapoda, therapsida and the terrestrial rock record across the Permian-Triassic boundary.

    Directory of Open Access Journals (Sweden)

    Jörg Fröbisch

    Full Text Available The end-Permian biotic crisis (~252.5 Ma represents the most severe extinction event in Earth's history. This paper investigates diversity patterns in Anomodontia, an extinct group of therapsid synapsids ('mammal-like reptiles', through time and in particular across this event. As herbivores and the dominant terrestrial tetrapods of their time, anomodonts play a central role in assessing the impact of the end-Permian extinction on terrestrial ecosystems. Taxonomic diversity analysis reveals that anomodonts experienced three distinct phases of diversification interrupted by the same number of extinctions, i.e. an end-Guadalupian, an end-Permian, and a mid-Triassic extinction. A positive correlation between the number of taxa and the number of formations per time interval shows that anomodont diversity is biased by the Permian-Triassic terrestrial rock record. Normalized diversity curves indicate that anomodont richness continuously declines from the Middle Permian to the Late Triassic, but also reveals all three extinction events. Taxonomic rates (origination and extinction indicate that the end-Guadalupian and end-Permian extinctions were driven by increased rates of extinction as well as low origination rates. However, this pattern is not evident at the final decline of anomodont diversity during the Middle Triassic. Therefore, it remains unclear whether the Middle Triassic extinction represents a gradual or abrupt event that is unique to anomodonts or more common among terrestrial tetrapods. The end-Permian extinction represents the most distinct event in terms of decline in anomodont richness and turnover rates.

  12. Cooperative and Human Aspects of Software Engineering (CHASE 2008)

    DEFF Research Database (Denmark)

    2008-01-01

    ethnographic research to experiments. Moreover, the background of attendees reflects the diversity of researchers in this domain, ranging from sociology to psychology, from informatics to software engineering. CHASE 1008 met its goals in presenting high-quality research and building community through a mixture...... of presentations, discussions, posters, and social activities....

  13. Volatilisation of diacetylmorphine: in vitro simulation of 'chasing the dragon'

    NARCIS (Netherlands)

    Klous, M. G.; Lee, W. C.; van den Brink, W.; van Ree, J. M.; Beijnen, J. H.

    2006-01-01

    In preparation for a trial on co-prescription of heroin to chronic treatment-resistant addicts, a pharmaceutical dosage form for smokable heroin was developed. During development of this product (a mixture of diacetylmorphine and caffeine), in vitro experiments were performed simulating 'chasing the

  14. Collective chasing behavior between cooperators and defectors in the spatial prisoner's dilemma.

    Directory of Open Access Journals (Sweden)

    Genki Ichinose

    Full Text Available Cooperation is one of the essential factors for all biological organisms in major evolutionary transitions. Recent studies have investigated the effect of migration for the evolution of cooperation. However, little is known about whether and how an individuals' cooperativeness coevolves with mobility. One possibility is that mobility enhances cooperation by enabling cooperators to escape from defectors and form clusters; the other possibility is that mobility inhibits cooperation by helping the defectors to catch and exploit the groups of cooperators. In this study we investigate the coevolutionary dynamics by using the prisoner's dilemma game model on a lattice structure. The computer simulations demonstrate that natural selection maintains cooperation in the form of evolutionary chasing between the cooperators and defectors. First, cooperative groups grow and collectively move in the same direction. Then, mutant defectors emerge and invade the cooperative groups, after which the defectors exploit the cooperators. Then other cooperative groups emerge due to mutation and the cycle is repeated. Here, it is worth noting that, as a result of natural selection, the mobility evolves towards directional migration, but not to random or completely fixed migration. Furthermore, with directional migration, the rate of global population extinction is lower when compared with other cases without the evolution of mobility (i.e., when mobility is preset to random or fixed. These findings illustrate the coevolutionary dynamics of cooperation and mobility through the directional chasing between cooperators and defectors.

  15. Cryptic sexual conflict in gift-giving insects: chasing the chase-away.

    Science.gov (United States)

    Sakaluk, Scott K; Avery, Rachel L; Weddle, Carie B

    2006-01-01

    The chase-away model of sexual selection posits that elaborate male sexual displays arise because they exploit preexisting biases in females' sensory systems and induce females to mate in a suboptimal manner. An essential element of this hypothesis is that such manipulation should quickly lead to female resistance to male displays. Nuptial food gifts may be a frequent conduit by which males attempt to influence the mating behavior of females against females' own reproductive interests. In decorated crickets Gryllodes sigillatus, such inducements come in the form of a spermatophylax, a gelatinous mass forming part of the male's spermatophore and consumed by the female after mating. We conducted experiments in which spermatophylaxes obtained from male G. sigillatus were offered as novel food gifts to females of a non-gift-giving species (Acheta domesticus) having no evolutionary history of spermatophylax consumption. Female A. domesticus that were allowed to consume the spermatophylax took significantly longer to remate than when given no such opportunity. In contrast, when female G. sigillatus were prevented from consuming their partners' nuptial gifts, there was no difference in their propensity to remate relative to females permitted to consume a food gift after mating. These results suggest that the spermatophylax synthesized by male G. sigillatus contains substances designed to inhibit the sexual receptivity of their mates but that female G. sigillatus have evolved reduced responsiveness to these substances.

  16. Late Permian (Zechstein) carbonate-facies maps, the Netherlands

    NARCIS (Netherlands)

    Geluk, M.C.

    2000-01-01

    The Late Permian Zechstein carbonates in the Southern Permian Basin were deposited under marine conditions. The carbonates form part of a largely progradational infill, with a gradual northward facies shift. The paleogeography of the Zechstein carbonate deposits has been reviewed recently on the

  17. Faunal migration into the Late Permian Zechstein Basin

    DEFF Research Database (Denmark)

    Sørensen, Anne Mehlin; Håkansson, Eckart; Stemmerik, Lars

    2007-01-01

    Late Permian bryozoans from the Wegener Halvø, Ravnefjeld and Schuchert Formations in East Greenland have been investigated. 14 genera are recognised.      Integration of the new bryozoan data from the Upper Permian of East Greenland with data on the distribution of Permian bryozoans along...... the northern margin of Pangea is used to test hypotheses concerning Late Palaeozoic evolution of the North Atlantic region. During the Permian, the Atlantic rift system formed a seaway between Norway and Greenland from the boreal Barents Shelf to the warm and arid Zechstein Basin. This seaway is considered...... to be the only marine connection to the Zechstein Basin and therefore the only possible migration route for bryozoans to enter the basin. The distribution of Permian bryozoans is largely in keeping with such a connection from the cool Barents Shelf past the East Greenland Basin to the warm Zechstein Basin...

  18. New discovery of Permian belemnoids in Hunan

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z.; Su, L. [Xiangtan Mining Institute, Hunan (China). Dept. of Geology

    1999-06-01

    The fossil belemnoids described here were discovered from the Upper Permian Dalong Formation in Hunan province. There are nearly one hundred specimens, including one genus and one species. The diagnosis of the species is as follows: Genus: palaeobelemnopsis Chen, 1982; Species: Palaeobelemnosis sp. The guard is small and slender, about six times the maximum transverse diameter in length, with outline slightly hastate or fusiform. The maximum transverse diameter locates the border between the apical region and the stem region, and is nearly cycloid or slightly compressed in the anterior of the alveolus. The apical angle is about 70{degree}. The median ventral groove is wide and shallow, and is sometimes absent. Two dorso-lateral grooves are apparent and extending from the alveolus to the apex. The Phragmocone is slender. The outer shape of the guard is very similar to that of P. sinensis and P. minor. Nevertheless, this species differs from the two latters in having many transverse lines covering on the whole surface of the guard. Because all of these specimens are fossils of external mold and no inner structures have been preserved except a piece of siphuncle remains, the species is not given a new species name. Permian belemnoids are rarely found and the Palaeobelemnopsis is a primitive genus of belemnoids, therefore these specimens have important significance for research on the origin of COLEOIDEA. 4 refs., 3 figs.

  19. Douglas Lowy and Nirali Shah discuss advancements in cancer treatment at the second annual Chasing Cancer Summit | Center for Cancer Research

    Science.gov (United States)

    On Monday, September 18, 2017, the second annual Chasing Cancer Summit was held at the Washington Post headquarters in downtown Washington, D.C. The live event brought together a group of experts, including CCR’s Douglas Lowy, M.D., and Nirali Shah, M.D., for discussions on the latest developments in cancer detection and treatment.  Read more...

  20. Comparative Earth history and Late Permian mass extinction

    Science.gov (United States)

    Knoll, A. H.; Bambach, R. K.; Canfield, D. E.; Grotzinger, J. P.

    1996-01-01

    The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction.

  1. Chasing The 'Like': Adolescent Use Of Social Networking Sites In Australia.

    Science.gov (United States)

    la Sala, Louise; Skues, Jason; Wise, Lisa; Theiler, Stephen

    2015-01-01

    The current study investigated how adolescents behave on Social Networking Sites (SNSs) and how they interpret the feedback they receive online from others. Thirty-four Australian adolescents (26 girls, 8 boys) aged 13 to 17 years participated in the study. Five semi-structured focus groups (3 mixed groups, 2 all-girl groups) were conducted to explore how adolescents perceive their own and others' SNS behaviours, the motivation underlying these behaviours, and the expected outcomes related to particular behaviours. Teenagers reported that they spend a good deal of time planning their SNS posts, felt that the information they posted was a true reflection of them as a person, and thus interpreted feedback ("likes") as measuring their self-worth. In contrast, some teenagers were perceived as "chasing the like" for status and popularity while not caring about how accurately their posts represented them as a person. A potential gender bias in these findings is discussed.

  2. Organic richness and gas generation potential of Permian Barren ...

    Indian Academy of Sciences (India)

    this study, a total of 32 core samples of Permian Barren Measures from four boreholes in Raniganj field of Damodar Basin ... number of factors like (i) quality and quantity of organic matter ...... Gujarat Energy Research and Management Insti-.

  3. Characteristics, stratigraphic architecture, and time framework of multi-order mixed siliciclastic and carbonate depositional sequences, outcropping Cisco Group (Late Pennsylvanian and Early Permian), Eastern Shelf, north-central Texas, USA

    Science.gov (United States)

    Yang, Wan; Kominz, Michelle A.

    2003-01-01

    The Cisco Group on the Eastern Shelf of the Midland Basin is composed of fluvial, deltaic, shelf, shelf-margin, and slope-to-basin carbonate and siliciclastic rocks. Sedimentologic and stratigraphic analyses of 181 meter-to-decimeter-scale depositional sequences exposed in the up-dip shelf indicated that the siliciclastic and carbonate parasequences in the transgressive systems tracts (TST) are thin and upward deepening, whereas those in highstand systems tracts (HST) are thick and upward shallowing. The sequences can be subdivided into five types on the basis of principal lithofacies, and exhibit variable magnitude of facies shift corresponding to variable extents of marine transgression and regression on the shelf. The sequence stacking patterns and their regional persistence suggest a three-level sequence hierarchy controlled by eustasy, whereas local and regional changes in lithology, thickness, and sequence type, magnitude, and absence were controlled by interplay of eustasy, differential shelf subsidence, depositional topography, and pattern of siliciclastic supply. The outcropping Cisco Group is highly incomplete with an estimated 6-11% stratigraphic completeness. The average duration of deposition of the major (third-order) sequences is estimated as 67-102 ka on the up-dip shelf and increases down dip, while the average duration of the major sequence boundaries (SB) is estimated as 831-1066 ka and decreases down dip. The nondepositional and erosional hiatus on the up-dip shelf was represented by lowstand deltaic systems in the basin and slope.

  4. The flora of Early Permian coal measures from the Parana Basin in Brazil: A review

    International Nuclear Information System (INIS)

    Iannuzzi, Roberto

    2010-01-01

    This paper presents an updated overview integrating both previous and newly published data on the most important floras found associated with Early Permian coal seams in the Parana Basin, Brazil. These floras occur within the Rio Bonito Formation and correspond to the Gondwana ''Glossopteris Flora.'' For this review, five floras are selected, in ascending stratigraphic order: the ''Sao Joao do Triunfo,'' ''Figueira,'' ''Quiteria,'' ''Morro do Papaleo'' and ''Irapua Bed'' floras. They are the best-known floras of the basin in terms of taxonomic composition, paleoecology and environments of deposition. An early-mid Sakmarian to earliest Artinskian age is indicated for the Rio Bonito Formation based on absolute radiometric and relative biostratigraphic ages. Integration of available information about the selected floras allows evaluation of taphonomic and paleoecological factors to provide a more comprehensive understanding of the Early Permian floral record in the Parana Basin. The variation observed in both the taxonomic composition of individual floras and in the frequency of occurrence of different plant groups is due to the broad range of environmental/edaphic conditions that prevailed in the many different depositional settings represented in the Rio Bonito Formation. A more precise age determination obtained for the plant-bearing deposits permits the establishment of a more confident correlation between the Early Permian floral succession in the Parana Basin and other Early Permian floral successions in other basins. The Sakmarian global warming favored the appearance of pecopterid and sphenopterid ferns amongst the spore-producing plants, and the glossopterids amongst the pollen-producing plants. (author)

  5. Permian vegetational Pompeii from Inner Mongolia and its implications for landscape paleoecology and paleobiogeography of Cathaysia.

    Science.gov (United States)

    Wang, Jun; Pfefferkorn, Hermann W; Zhang, Yi; Feng, Zhuo

    2012-03-27

    Plant communities of the geologic past can be reconstructed with high fidelity only if they were preserved in place in an instant in time. Here we report such a flora from an early Permian (ca. 298 Ma) ash-fall tuff in Inner Mongolia, a time interval and area where such information is filling a large gap of knowledge. About 1,000 m(2) of forest growing on peat could be reconstructed based on the actual location of individual plants. Tree ferns formed a lower canopy and either Cordaites, a coniferophyte, or Sigillaria, a lycopsid, were present as taller trees. Noeggerathiales, an enigmatic and extinct spore-bearing plant group of small trees, is represented by three species that have been found as nearly complete specimens and are presented in reconstructions in their plant community. Landscape heterogenity is apparent, including one site where Noeggerathiales are dominant. This peat-forming flora is also taxonomically distinct from those growing on clastic soils in the same area and during the same time interval. This Permian flora demonstrates both similarities and differences to floras of the same age in Europe and North America and confirms the distinct character of the Cathaysian floral realm. Therefore, this flora will serve as a baseline for the study of other fossil floras in East Asia and the early Permian globally that will be needed for a better understanding of paleoclimate evolution through time.

  6. The illusion of handy wins: Problem gambling, chasing, and affective decision-making.

    Science.gov (United States)

    Nigro, Giovanna; Ciccarelli, Maria; Cosenza, Marina

    2018-01-01

    Chasing losses is a behavioral marker and a diagnostic criterion for gambling disorder. It consists in continuing gambling to recoup previous losses. Although chasing has been recognized playing a central role in gambling disorder, research on this topic is relatively scarce, and it remains unclear whether chasing affects decision-making in behavioral tasks in which participants gain or loss some money. Even if several studies found that the more the gambling involvement, the poorer the decision-making, to date no research investigated the role of chasing in decision-making. The study aimed to first investigate the relation between chasing and decision-making in adult gamblers. One hundred and four VLT players were administered the South Oaks Gambling Screen (SOGS), a computerized task measuring chasing, and the Iowa Gambling Task (IGT). Correlation analysis showed that the higher the SOGS scores, the higher the propensity to chase, and the poorer the decision-making performance. Regression analysis revealed that chasing propensity and gambling severity predicted IGT performance. Mediation analysis indicated that the association between gambling severity and poor decision-making is mediated by chasing. Gambling severity was assessed by means of a self-report measure. The generalizability of findings is limited, since the study focused only on VLT players. This study provides the first evidence that chasing, along with gambling severity, affects decision-making, at least in behavioral tasks involving money. Since chasers and non-chasers could be two different sub-types of gamblers, treatment protocols should take into account the additive role of chasing in gambling disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Solution or suspension - Does it matter for lipid based systems? In vivo studies of chase dosing lipid vehicles with aqueous suspensions of a poorly soluble drug.

    Science.gov (United States)

    Larsen, A T; Holm, R; Müllertz, A

    2017-08-01

    In this study, the potential of co-administering an aqueous suspension with a placebo lipid vehicle, i.e. chase dosing, was investigated in rats relative to the aqueous suspension alone or a solution of the drug in the lipid vehicle. The lipid investigated in the present study was Labrafil M2125CS and three evaluated poorly soluble model compounds, danazol, cinnarizine and halofantrine. For cinnarizine and danazol the oral bioavailability in rats after chase dosing or dosing the compound dissolved in Labrafil M21515CS was similar and significantly higher than for the aqueous suspension. For halofantrine the chase dosed group had a tendency towards a low bioavailability relative to the Labrafil M2125CS solution, but still a significant higher bioavailability relative to the aqueous suspension. This could be due to factors such as a slower dissolution rate in the intestinal phase of halofantrine or a lower solubility in the colloidal structures formed during digestion, but other mechanisms may also be involved. The study thereby supported the potential of chase dosing as a potential dosing regimen in situations where it is beneficial to have a drug in the solid state, e.g. due to chemical stability issues in the lipid vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. 78 FR 69663 - Jonathan and Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption

    Science.gov (United States)

    2013-11-20

    ... Jayne Chase Troy Mills Hydroelectric Inc.; Notice of Transfer of Exemption 1. By letter filed October 15, 2013, Jonathan Chase informed the Commission that the exemption from licensing for the Troy Hydroelectric Project, FERC No. 13381, originally issued December 2, 2011,\\1\\ has been transferred to Troy Mills...

  9. Progress on the palynostratigraphy of the Permian strata in Rio Grande do Sul State, Paraná Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Souza Paulo A.

    2005-01-01

    Full Text Available A review of published papers and results of analysis of new material have allowed improvements on the palynostratigraphy of the Permian strata of the Paraná Basin in Rio Grande do Sul State. Based on first and last occurrences of certain species of pollen taxa, two palynozones are formalized, these are the Vittatina costabilis and Lueckisporites virkkiae Interval Zones, in ascending order. The Vittatina costabilis Interval Zone is subdivided into two units, in ascending order the Protohaploxypinus goraiensis and the Hamiapollenites karrooensis Subzones, and is recognized from the glacial (Itararé Group and post-glacial sequence (Rio Bonito Formation and the base of the Palermo Formation. The Lueckisporites virkkiae Interval Zone occurs from the uppermost Rio Bonito Formation, through the Palermo and Irati formations, and into the Serra Alta and Teresina formations. The main characteristics and reference sections are established, as well as additional criteria to recognize biostratigraphical units, in accordance with the International Stratigraphic Guide. Palynostratigraphical correlation suggests that the Vittatina costabilis Zone concerns the Early Permian (early Cisuralian, while the Lueckisporites virkkiae is regarded as late Early Permian to early Middle Permian (late Cisularian to early Guadalupian.

  10. Significance chasing in research practice: causes, consequences and possible solutions.

    Science.gov (United States)

    Ware, Jennifer J; Munafò, Marcus R

    2015-01-01

    The low reproducibility of findings within the scientific literature is a growing concern. This may be due to many findings being false positives which, in turn, can misdirect research effort and waste money. We review factors that may contribute to poor study reproducibility and an excess of 'significant' findings within the published literature. Specifically, we consider the influence of current incentive structures and the impact of these on research practices. The prevalence of false positives within the literature may be attributable to a number of questionable research practices, ranging from the relatively innocent and minor (e.g. unplanned post-hoc tests) to the calculated and serious (e.g. fabrication of data). These practices may be driven by current incentive structures (e.g. pressure to publish), alongside the preferential emphasis placed by journals on novelty over veracity. There are a number of potential solutions to poor reproducibility, such as new publishing formats that emphasize the research question and study design, rather than the results obtained. This has the potential to minimize significance chasing and non-publication of null findings. Significance chasing, questionable research practices and poor study reproducibility are the unfortunate consequence of a 'publish or perish' culture and a preference among journals for novel findings. It is likely that top-down change implemented by those with the ability to modify current incentive structure (e.g. funders and journals) will be required to address problems of poor reproducibility. © 2014 Society for the Study of Addiction.

  11. Exploratory shaft conceptual design report: Permian Basin

    International Nuclear Information System (INIS)

    1983-07-01

    This conceptual design report summarizes the conceptualized design for an exploratory shaft facility at a representative site in the Permian Basin locatd in the western part of Texas. Conceptualized designs for other possible locations (Paradox Basin in Utah and Gulf Interior Region salt domes in Louisiana and Mississippi) are summarized in separate reports. The purpose of the exploratory shaft facility is to provide access to the reference repository horizon to permit in situ testing of the salt. The in situ testing is necessary to verify repository salt design parameters, evaluate isotropy and homogeneity of the salt, and provide a demonstration of the constructability and confirmation of the design to gain access to the repository. The fundamental purpose of this conceptual design report is to assure the feasibility of the exploratory shaft project and to develop a reliable cost estimate and realistic schedule. Because a site has not been selected and site-specific subsurface data are not available, it has been necessary to make certain assumptions in order to develop a conceptual design for an exploratory shaft facility in salt. As more definitive information becomes available to support the design process, adjustments in the projected schedule and estimated costs will be required

  12. What are the underlying units of perceived animacy? Chasing detection is intrinsically object-based.

    Science.gov (United States)

    van Buren, Benjamin; Gao, Tao; Scholl, Brian J

    2017-10-01

    One of the most foundational questions that can be asked about any visual process is the nature of the underlying 'units' over which it operates (e.g., features, objects, or spatial regions). Here we address this question-for the first time, to our knowledge-in the context of the perception of animacy. Even simple geometric shapes appear animate when they move in certain ways. Do such percepts arise whenever any visual feature moves appropriately, or do they require that the relevant features first be individuated as discrete objects? Observers viewed displays in which one disc (the "wolf") chased another (the "sheep") among several moving distractor discs. Critically, two pairs of discs were also connected by visible lines. In the Unconnected condition, both lines connected pairs of distractors; but in the Connected condition, one connected the wolf to a distractor, and the other connected the sheep to a different distractor. Observers in the Connected condition were much less likely to describe such displays using mental state terms. Furthermore, signal detection analyses were used to explore the objective ability to discriminate chasing displays from inanimate control displays in which the wolf moved toward the sheep's mirror-image. Chasing detection was severely impaired on Connected trials: observers could readily detect an object chasing another object, but not a line-end chasing another line-end, a line-end chasing an object, or an object chasing a line-end. We conclude that the underlying units of perceived animacy are discrete visual objects.

  13. PERMIAN BRACHIOPODS FROM KARAKORUM (PAKISTAN PART. 3.

    Directory of Open Access Journals (Sweden)

    LUCIA ANGIOLINI

    2001-11-01

    Full Text Available Late Wordian (Guadalupian brachiopods from Member 2 of the Panjshah Formation in the Karakorum (N Pakistan are described. The brachiopod assemblage, dated by the associated fusulinids and conodonts, consists of 29 genera (3 of which are questionable and 1 unidentifiable of the orders Productida, Orthida, Rhynchonellida, Athyridida, Spiriferida and Terebratulida. Hunzininae, a new subfamily of the Spiriferellidae is proposed; it includes Darbandia n. gen., with type species D. vagabunda n. sp. and Elivina chapursani n. sp. A third new species is assigned to the genus Anchorhynchia of the family Wellerellidae: A. cimmerica n. sp.A quantitative biostratigraphic analysis demonstrates two major faunal changes in the Elivina chapursani- Chapursania tatianae Assemblage Zone of the upper part of Member 2, which are not strictly linked to lithological changes. This biozone is correlated with the brachiopod faunas of the Gnishik Formation of Armenia and those of the basal Takhtabulak Formation of SE Pamir.The faunal elements of the Elivina chapursani- Chapursania tatianae Assemblage Zone are an admixture of wide-ranging, Tethyan (particularly abundant, Gondwanan and endemic (Cimmerian genera, representing a transitional fauna and a biostratigraphic tool for intercontinental correlation, which are particularly problematic in this time interval. The Panjshah transitional fauna demonstrates the persistence of the Transhimalayan Province of the Cimmerian Region into the late Guadalupian, which originated at the end of the Cisuralian and occupied Armenia, Central Afghanistan, Karakorum and SE Pamir. It provides also some insights into the biodiversity pattern before the mass extinction at the end of the Guadalupian, and suggests that this event was as rapid as the end- Permian mass extinction, at least in Central Asia. 

  14. Child and adolescent service experience (ChASE): measuring service quality and therapeutic process.

    Science.gov (United States)

    Day, Crispin; Michelson, Daniel; Hassan, Imren

    2011-11-01

    OBJECTIVES. Dissatisfaction with services has been associated with poorer child mental health outcomes, early treatment termination as well as disagreements over the nature of mental health difficulties, reasons for referral and therapy goals. The development of straightforward, reliable, and accurate methods of eliciting service users' views is essential within child and adolescent mental health care. This paper describes the development of the child and adolescent service experience (ChASE), a tool to measure children and young people's service experience DESIGN. The study comprises a non-experimental, cross-sectional design. METHODS. Participants were 132 mental health service users aged 8-18 years. Participants and their main carer completed the ChASE, Parent Satisfaction Questionnaire (PSQ) (Stallard, 1996) and Strengths and Difficulties (SDQ) Impact Supplement. Clinicians completed the SDQ Impact Supplement and provided clinical activity data. A sub-sample of participants completed the ChASE on a second occasion, 6 weeks after the completion of the first questionnaire. RESULTS. Scrutiny of ChASE data indicated high levels of completion. Principal axis factoring identified three factors within the ChASE: Relationship, Privacy, and Session Activity. The ChASE has good internal consistency and test-retest reliability. Significant correlations were found between the ChASE and carer satisfaction, service use, and youth clinical outcomes. CONCLUSIONS. The ChASE is a short, psychometrically robust tool for routine measurement of children, and young people's experience of mental health services, which users can complete easily. The results underline the importance of alliance factors to children and young people and their association with clinical improvement as well as the potential for the ChASE to be used a measure of children's therapeutic progress and alliance. ©2011 The British Psychological Society.

  15. The CHilean Automatic Supernova sEarch (CHASE)

    Science.gov (United States)

    Pignata, G.; Maza, J.; Hamuy, M.; Antezana, R.; Gonzales, L.

    2009-05-01

    One of the most important challenges in modern cosmology will be to figure out the origin of the dark energy, to measure its equation of state and the time rate with which it changes (described by parameters w and w'). The measurement of these parameters will require high levels of accuracy in the Supernova (SN) Type Ia distances and various sources of systematic error such as reddening corrections and possible evolution in the SNcharacteristics which could couple with redshift and mimic the cosmological signal of interest. Fortunately, these concerns can be fully addressed through the comprehensive study of SNe in the local (z < 0.05) universe. Although Type II plateau SNe are not as luminous as SNe Ia, they afford two important, independent routes to cosmological distances using the Expanding Photosphere Method and the Standardized Candle Method. To assess the performance of these techniques a nearby sample of Type II SNe is necessary. With the purpose of addressing these issues the Millennium Center for Supernova Studies (MCSS) is teaming up with the Carnegie Supernova Project (CSP) to carry out an optical and near infrared (photometry, spectroscopy and polarimetry) follow up of nearby SNe. Unfortunately, the majority of the SNe observed by the MCSS and the CSP are discovered by searches carried out from the northern hemisphere. This entails a number of observational difficulties, in particular, it reduces the number of SNe for which the follow-up starts at very early epochs. The aim of the CHASE project is to remove this search bias by discovering young Southern SNe that will be extensively observed by the MCSS and the CSP. In the first nine-months of operation, CHASE has discovered two SNe: SN007oc (CBET 1114) and SN007pl (CBET 1130), thus demonstrating the feasibility of the survey.

  16. The Permian mega floras of Uruguay.A synthesis

    International Nuclear Information System (INIS)

    Crisafulli, A.; Herbst, R.

    2007-01-01

    The Permian megafloras of Uruguay. A synthesis. An analysis of the impression and fossil wood floras from the Permian of Uruguay is given through a series of Tables. These show : (1) the list of taxa, (2) anatomical characters of the woods, (3) data on the microfloral associations, (4) paleoenvironmental information and (5) comparisons with contemporaneous Gondwana floras. The evolutionary degree of the woods is briefly analyzed where they correspond to the so-called ''transition xilotaphofloras'' as they present typical Paleozoic anatomical characters but with secondary xylem of more advanced characteristics. (author)

  17. Early Permian intrusions in the Paleozoic sediments of the Eastern North Sea area

    DEFF Research Database (Denmark)

    Clausen, O.R.; Andresen, Katrine Juul; Rasmussen, Jens Andreas

    in the Northern Permian Basin which in the eastern North Sea is separated from the Southern Permian Basin by the Ringkøbing-Fyn High. The Permian basins were initiated during thermal subsidence following a late Carboniferous- early Permian rifting phase associated with extensive igneous activity recorded across...... the entire North Sea Basin. The easternmost intrusions and extrusions have been associated to the “Skagerrak-Centered Large Igneous Province” that has an early Permian age of c. 297 Ma. Compared to the Southern Permian Basin which historically has been intensely investigated because of the known presence...... of hydrocarbons within the Paleozoic sediments, the Northern Permian Basin has gained much less interest outside the hydrocarbon producing Mesozoic graben systems. This is mainly due to an apparent lack of potential source rocks. A major E-W striking northward dipping fault system characterizes the study area...

  18. Chasing molecules: poisonous products, human health, and the promise of green chemistry

    National Research Council Canada - National Science Library

    Grossman, Elizabeth

    2009-01-01

    In Chasing Molecules, investigative journalist Elizabeth Grossman opens the door on a new world of chemistry-green chemistry - and the scientists who are unearthing the field's potential to transform...

  19. Organic richness and gas generation potential of Permian Barren

    Indian Academy of Sciences (India)

    The organic geochemistry of shales in terms of its organic richness, hydrocarbon source potential, thermal maturity, depositional environment, etc., are essential stipulations for shale gas resources assessment. In this study, a total of 32 core samples of Permian Barren Measures from four boreholes in Raniganj field of ...

  20. Terrestrial acidification during the end-Permian biosphere crisis?

    NARCIS (Netherlands)

    Sephton, Mark A.; Jiao, Dan; Engel, Michael H.; Looy, Cindy V.; Visscher, Henk

    Excessive acid rainfall associated with emplacement of the Siberian Traps magmatic province is increasingly accepted as a major contributing factor to the end-Permian biosphere crisis. However, direct proxy evidence of terrestrial acidification is so far not available. In this paper, we seek to

  1. Progress in the Gondwanan Carboniferous–Permian palynology ...

    Indian Academy of Sciences (India)

    The first section describes challenges in the Carboniferous–Permian Gondwanan stratigraphic palynology, and progress in techniques such as presence of the 'rare-marine intervals', and 'radiometric dating' in some Gondwanan successions, e.g., South Africa, Australia and South America, as tools to confidently calibrate ...

  2. Palynostratigraphy of Permian succession in the Mand–Raigarh ...

    Indian Academy of Sciences (India)

    Palynofloras have been recorded from the Barakar Formation in the Borehole MBKW-3, Barpali–Karmitikra Block, Mand–Raigarh Coalfield, Chhattisgarh. Three distinct palynoassemblages have been identified and referred to the following palynoassemblage zones – Gondisporites raniganjensis (Latest Permian); ...

  3. On the origin of the southern Permian Basin, Central Europe.

    NARCIS (Netherlands)

    van Wees, J.D.A.M.; Stephenson, R.A.; Ziegler, P.A.; Bayer, U.; McCann, T.; Dadlez, R.; Gaupp, R.; Narkiewicz, M.; Bitzer, F.; Scheck, M.

    2000-01-01

    A detailed study of the structural and stratigraphic evolution of the Southern Permian Basin during latest Carboniferous to Early Jurassic times, supported by quantitative subsidence analyses and forward basin modelling for 25 wells, leads us to modify the conventional model for the

  4. Evidence of lacustrine sedimentation in the Upper Permian Bijori

    Indian Academy of Sciences (India)

    The Upper Permian Bijori Formation of the Satpura Gondwana basin comprising fine- to coarsegrained sandstone, carbonaceous shale/mudstone and thin coal bands was previously interpreted as the deposits of meandering rivers. The present study documents abundance of wave ripples, hummocky and swaley ...

  5. Review of monolete-producing Carboniferous-Permian sphenophylls

    Czech Academy of Sciences Publication Activity Database

    Libertín, M.; Bek, Jiří

    2008-01-01

    Roč. 2008, č. 2 (2008), s. 168-168 ISSN 0946-8978. [International Palynological Congress /12./ ; International Organisation of Palaeobotany Conference /8./. 30.08.2008-05.09.2008, Bonn] R&D Projects: GA AV ČR IAA300130503 Institutional research plan: CEZ:AV0Z30130516 Keywords : Carboniferous * Permian * sphenophylls Subject RIV: DB - Geology ; Mineralogy

  6. Palynostratigraphy of Permian succession in the Mand–Raigarh ...

    Indian Academy of Sciences (India)

    Palynofloras have been recorded from the Barakar Formation in the Borehole MBKW-3, Barpali–. Karmitikra Block, Mand–Raigarh Coalfield, Chhattisgarh. Three distinct palynoassemblages have been identified and referred to the following palynoassemblage zones – Gondisporites raniganjensis (Latest. Permian); ...

  7. Late Carboniferous to Late Permian carbon isotope stratigraphy

    DEFF Research Database (Denmark)

    Buggisch, Werner; Krainer, Karl; Schaffhauser, Maria

    2015-01-01

    An integrated study of the litho-, bio-, and isotope stratigraphy of carbonates in the Southern Alps was undertaken in order to better constrain δ13C variations during the Late Carboniferous to Late Permian. The presented high resolution isotope curves are based on 1299 δ13Ccarb and 396 δ13Corg...

  8. Gas hydrate contribution to Late Permian global warming

    Czech Academy of Sciences Publication Activity Database

    Majorowicz, J.; Grasby, S. E.; Šafanda, Jan; Beauchamp, B.

    2014-01-01

    Roč. 393, May (2014), s. 243-253 ISSN 0012-821X Institutional support: RVO:67985530 Keywords : Latest Permian extinction * gas hydrates * carbon isotope shift Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 4.734, year: 2014

  9. Conodont succession and reassessment of major events around the Permian-Triassic boundary at the Selong Xishan section, southern Tibet, China

    Science.gov (United States)

    Yuan, Dong-Xun; Zhang, Yi-Chun; Shen, Shu-Zhong

    2018-02-01

    A major discrepancy for the age of the Selong Group from middle Cisuralian (Early Permian) to Changhsingian resulted from previous reports of Sakmarian, Kungurian and Guadalupian (Middle Permian) conodonts and Lopingian (Late Permian) brachiopods. Recently, Cisuralian and Guadalupian conodonts were reported again from the Selong Group and the basal part of the Kangshare Formation at the Selong section, but the age discrepancy remains. We present our conodont materials based on large samples collected from the Selong Group and our interpretation based on identifications using a sample population approach. Three conodont zones are recognized in our re-investigation of the upper part of the Selong Group. They include the Vjalovognathus sp., the Mesogondolella hendersoni, and the M. sheni zones, in ascending order. These zones are overlain by the basal Triassic Hindeodus parvus Zone and the Otoceras woodwardi Zone. Our reassessment of conodonts reported by previous studies from Selong and nearby sections suggest that all specimens consistently point to a Lopingian age; the upper part of the Selong Group is latest Changhsingian in age based on the presence of Clarkina orchardi and Mesogondolella sheni. Previously reported early Cisuralian and Guadalupian conodonts are misidentified using a form species concept. A hiatus may be present at the erosional surface between the Selong Group and the Waagenites Bed of the basal part of the Kangshare Formation. However, the hiatus is minimal because conodont and brachiopod assemblages above and below this surface are very similar, and it results from a latest Changhsingian transgression just before the extinction that follows a global latest Changhsingian regression. There is a distinct rapid end-Permian mass extinction at Selong within the Waagenites Bed, as indicated by the disappearances of all benthic brachiopods, rugose corals and Permian bryozoans. The burst of Clarkina species in the Waagenites Bed and throughout the

  10. Chelate chase of radiopharmaceuticals reversibly bound to monoclonal antibodies improves dosimetry

    International Nuclear Information System (INIS)

    Goodwin, D.A.; Smith, S.I.; Meares, C.F.; David, G.S.; McTigue, M.; Finston, R.A.

    1986-01-01

    One hundred micrograms of monoclonal antibody (MoAb) CHA 255 with a binding constant Kb of 4 x 10 9 was complexed with indium-111 labeled BLEDTA II, GLEDTA IV, benzyl EDTA, and an EDTA conjugate of Fab. The 24-hour tumor and organ distribution in BALB/c mice bearing KHJJ tumors was studied for each compound alone, the antibody complex, and 3 hours following a chelate chase of the antibody complex. Whole-body biological half-life was measured for 7 days with and without a chelate chase for each antibody complex. The 24-hour whole-body counts dropped 20-60% within 3 hours of administering the chelate chase. Blood concentration fell over 89% within 3 hours of administering the chase and there was a decrease in concentration in all organs, except the kidneys, of 10 to 85%. Theoretical equivalent human doses were calculated from the 24-hour organ concentrations, effective half-life, and MIRD 11 S values (absorbed dose per cumulated activity). Liver and spleen were the target organs, with the dose ranging from 0.50 to 3.91 rads per millicurie. The reduction in organ radiation dose varied up to 95% following the chelate chase. Rapid selective renal clearance of chelate labeled radiopharmaceuticals by competitive inhibition (chelate chase) of their reversible binding to monoclonal antibodies, greatly improves the radiation dosimetry of tumor imaging agents. 28 references, 5 figures, 5 tables

  11. Alexithymia predicts loss chasing for people at risk for problem gambling.

    Science.gov (United States)

    Bibby, Peter A; Ross, Katherine E

    2017-12-01

    Background and aims The aim of this research was to investigate the relationship between alexithymia and loss-chasing behavior in people at risk and not at risk for problem gambling. Methods An opportunity sample of 58 (50 males and 8 females) participants completed the Problem Gambling Severity Index and the Toronto Alexithymia Scale (TAS-20). They then completed the Cambridge Gambling Task from which a measure of loss-chasing behavior was derived. Results Alexithymia and problem gambling risk were significantly positively correlated. Subgroups of non-alexithymic and at or near caseness for alexithymia by low risk and at risk for problem gambling were identified. The results show a clear difference for loss-chasing behavior for the two alexithymia conditions, but there was no evidence that low and at-risk problem gamblers were more likely to loss chase. The emotion-processing components of the TAS-20 were shown to correlate with loss chasing. Discussion and conclusion These findings suggest that loss-chasing behavior may be particularly prevalent in a subgroup of problem gamblers those who are high in alexithymia.

  12. Late Permian wood-borings reveal an intricate network of ecological relationships.

    Science.gov (United States)

    Feng, Zhuo; Wang, Jun; Rößler, Ronny; Ślipiński, Adam; Labandeira, Conrad

    2017-09-15

    Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetle speciosity is attributable to myriad life habits, particularly diverse-feeding strategies involving interactions with plant substrates, such as wood. However, the life habits and early evolution of wood-boring beetles remain shrouded in mystery from a limited fossil record. Here we report new material from the upper Permian (Changhsingian Stage, ca. 254-252 million-years ago) of China documenting a microcosm of ecological associations involving a polyphagan wood-borer consuming cambial and wood tissues of the conifer Ningxiaites specialis. This earliest evidence for a component community of several trophically interacting taxa is frozen in time by exceptional preservation. The combination of an entry tunnel through bark, a cambium mother gallery, and up to 11 eggs placed in lateral niches-from which emerge multi-instar larval tunnels that consume cambium, wood and bark-is ecologically convergent with Early Cretaceous bark-beetle borings 120 million-years later.Numerous gaps remain in our knowledge of how groups of organisms interacted in ancient ecosystems. Here, Feng and colleagues describe a late Permian fossil wood-boring beetle microcosm, with the oldest known example of complex tunnel geometry, host tissue response, and the presence of fungi within.

  13. An early geikiid dicynodont from the Tropidostoma Assemblage Zone (late Permian of South Africa

    Directory of Open Access Journals (Sweden)

    Christian F. Kammerer

    2017-01-01

    Full Text Available Based on specimens previously identified as Tropidostoma, a new taxon of dicynodont (Bulbasaurus phylloxyron gen. et sp. nov. from the Karoo Basin of South Africa is described. Bulbasaurus is a medium-sized dicynodont (maximum dorsal skull length 16.0 cm restricted to the Tropidostoma Assemblage Zone (early Lopingian of the Beaufort Group. Bulbasaurus can be distinguished from Tropidostoma by an array of characters including the presence of a tall, sharp premaxillary ridge, large, rugose, nearly-confluent nasal bosses, a nasofrontal ridge, massive tusks, robust pterygoids, prominently twisted subtemporal bar, and absence of a distinct postfrontal. Inclusion of Bulbasaurus in a phylogenetic analysis of anomodont therapsids recovers it as a member of Geikiidae, a clade of otherwise later Permian dicynodonts such as Aulacephalodon and Pelanomodon. Bulbasaurus exhibits many of the characters typical of adult Aulacephalodon, but at substantially smaller skull size (these characters are absent in comparably-sized Aulacephalodon juveniles, suggesting that the evolution of typical geikiid morphology preceded gigantism in the clade. Bulbasaurus is the earliest known geikiid and the only member of the group known from the Tropidostoma Assemblage Zone; discovery of this taxon shortens a perplexing ghost lineage and indicates that abundant clades from the later Permian of South Africa (e.g., Geikiidae, Dicynodontoidea may have originated as rare components of earlier Karoo assemblage zones.

  14. Stratigraphy and paleontology of Lower Permian rocks north of Cananea, northern Sonora, Mexico

    Science.gov (United States)

    Blodgett, R.B.; Moore, T.E.; Gray, F.

    2002-01-01

    Lower Permian carbonate and overlying red bed clastic rocks are present in a 2 km2 stratigraphic window in the vicinity of Rancho La Cueva, Santa Cruz sheet (scale 1:50,000), northern Sonora, Mexico. This exposure lies unconformably beneath predominantly intermediate Upper Cretaceous volcanics yielding 40Ar/39Ar ages of 73.4?? 0.18 and 71.1 ?? 0.35 Ma. The lower part of the Permian succession consists of light- to medium-gray colored limestones of the Colina Limestone, with a minimum thickness of 235 m. Sedimentary features suggest shallow water, slightly restricted depositional environments. Although lacking observable fossils for the most part, two intervals of richly fossiliferous, silicified shell beds are present near the base and top of the Colina Limestone. The lower fauna consist mostly of gastropods and bivalves. The presence of a new microdomatid gastropod species. Glyptospira sonorensis n. sp., close to Glytospira arelela Plas, suggests a late Wolfcampian age for this horizon. The upper fauna are predominantly molluscan dominated (gastropods and bivalves), but some brachiopods (productids and the rhynchonellid genus Pontisia) are also present. Gastropod genera include Bellerophon, Warthia, Euomphalus (represented by the species, Euomphalus kaibabensis Chronic), Baylea, Worthenia, Naticopsis, Goniasma, Kinishbia, Cibecuia, and Glyptospira. The gastropods suggest a Leonardian (late Early Permian) age for this horizon, and many of the species have previously been recorded from the Supai Group and Kaibab Formation of northern and central Arizona. The Colina Limestone is conformably overlain by 11.2 m of light-gray lime mudstone and dolostone, assigned here to the Epitaph Dolomite, which in turn is succeeded by 58.8 m of red-colored sandstone and gray lime mudstone, assigned here to the Scherrer Formation. This Lower Permian succession is significant because it further strengthens the stratigraphic ties of southeastern Arizona rocks with those of northern

  15. THE SEDIMENTOLOGY OF THE LOWER PERMIAN DANDOT FORMATION: A COMPONENT OF THE GONDWANA DEGLACIATION SEQUENCE OF THE SALT RANGE, PAKISTAN

    Directory of Open Access Journals (Sweden)

    IRFAN U. JAN

    2016-03-01

    Full Text Available The Dandot Formation is a part of the Lower Permian, dominantly continental, Gondwanan Nilawahan Group in the Salt Range, Pakistan. The formation conformably overlies the glacio-fluvial Tobra Formation and has a sharp conformable contact with the overlying fluvio-continental Warchha Sandstone. Sedimentary analyses show that the Dandot Formation consists of: 1. bioturbated sandstone lithofacies (L1, 2. dark green mudstone/shale lithofacies (L2, 3. flaser bedded sandstone lithofacies (L3, 4. rippled sandstone lithofacies (L4, 5. cross-bedded sandstone lithofacies (L5, and 6. planar sandstone lithofacies (L6. These can be grouped into shoreface, inner shelf, and tidal flat and estuarine facies associations, deposited in shallow marine to intertidal environments. The upper part of the Tobra Formation at the Choa-Khewra road section, where it conformably underlies the Dandot Formation, contains palynomorphs assignable to the earliest Permian 2141B Biozone. In south Oman, the 2141B Biozone is closely associated with the Rahab Shale Member, a widespread shale unit which is considered to represent part of a Permian deglaciation sequence which culminates in the marine beds of the Lower Gharif Member, interpreted as due to post glacial marine transgression. Thus, the Tobra Formation and the overlying marine Dandot Formation may form part of a similar deglaciation sequence.

  16. ECMO: Improving our Results by Chasing the Rabbits

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Canêo

    2015-12-01

    Full Text Available ABSTRACT As Marcelo Giugale published in the Financial Times, Latin America, on the whole, has not excelled at innovation - doing the same things in a new and better way or at doing new things. It has been slow to acquire, adopt and adapt technologies by this time available in other places[1]. Although extracorporeal membrane oxygenation (ECMO is not a new technology, its use in Latin America is not widespread as needed. Furthermore, we still have a number centers doing ECMO, not reporting their cases, lacking a structured training program and not registered with the extracorporeal life support organization (ELSO. With this scenario, and accepting that ECMO is the first step in any circulatory support program, it is difficult to anticipate the incorporation of new and more complex devices as the technologically advanced world is currently doing. However, the good news is that with the support of experts from USA, Europe and Canada the results in Latin America ELSO'S centers are improving by following its guidelines for training, and using a standard educational process. There is no doubt that we can learn a great deal from the high velocity organizations - the rabbits - whom everyone chases but never catches, that manage to stay ahead because of their endurance, responsiveness, and their velocity in self-correction[2].

  17. Patterns of Light Chasing the Spectrum from Aristotle to LEDs

    CERN Document Server

    Beeson, Steven

    2008-01-01

    Light is all around us – even when we do not see it. Our eyes do not detect the higher energy and shorter-than-visible-wavelength ultraviolet radiation, yet we know it is there from the sunburn we receive in Arizona. We know that window glass can block ultraviolet rays so we do not get a burn while driving with the windows rolled up. Our eyes do not detect the low-energy, long-wavelength infrared (IR) radiation but we know it exists from discussions of war applications and televised images of guided weapons targets. We also know about radio waves from the little boxes that talk to us and x-rays from the dentist's office. Patterns of Light, Chasing the Spectrum from Aristotle to LEDs, written by Steve Beeson and Jim Mayer starts with the visible – the straight path of light. It continues with chapters detailing reflection (mirrors, storefront windows) and refraction (eyeglasses, binoculars). Color is then introduced with the query "Why is the sky blue?" After answering that and other similar questions ("Wh...

  18. Paleogeographic changes across the Pennsylvanian-Permian boundary within the Mid-Continent (USA) inferred from detrital zircon geochronology of continental deposits

    Science.gov (United States)

    Soreghan, M. J.; Soreghan, G. S.

    2017-12-01

    The Permo-Pennsylvanian was characterized by intense orogenesis associated with Pangaean assembly, and profound climate shifts as earth transitioned from full icehouse conditions in the Pennsylvanian-early Permian to collapse into greenhouse conditions by latest Permian time. The modern U.S. Midcontinent was part of equatorial western Pangaea (North America) sandwiched between a continental-scale orogenic zone to the east and south (Appalachian-Ouachita-Marathon orogenic belt) and a series of basement-cored, intra-plate uplifts along western Pangaea (Ancestral Rocky Mountains). Here, we present a compilation of detrital zircon geochronology data from the Permo-Pennsylvanian of the Midcontinent as well as coeval strata of the east and west to explore sediment dispersal and potential tectonic and climatic influences on these provenance signatures. Zircon provenance data come from mostly eolian and fluvial silt- and sandstones of Early Pennsylvanian through Mid Permian age, although some data include marine sandstones. Our new data were acquired by LA-ICPMS at the University of Arizona Laserchron, and predominant age groups include >2500 Ma (Archean), 1600-1800 Ma (Yavapai-Matzatzal), 1300-900 Ma (Grenville), 790-570 Ma (Neoproterozoic), and 480-360 (E-M Paleozoic). However, the relative distributions of these populations exhibit distinctive temporal differences, especially across the Pennsylvanian-Permian boundary, but also spatially in comparison to published data from the Appalachian-Ouachita-Marathon basin, Ancestral Rocky Mountain basins, and the western Pangaean margin. Although the Central Pangaean Mountains, and in particular the Grenville-age basement rocks, were a dominant source of sediment to the Midcontinent, the data suggest an abrupt introduction of Neoproterozoic zircons in the early Permian. This signature also appears within the Ancestral Rocky Mountains region, but is rare along the western margin and the Appalachian basin in the early Permian. This

  19. Neutron activation analysis of Permian-Triassic boundary layer samples at the Selong Site in China

    International Nuclear Information System (INIS)

    Miyamoto, Y.; Sakamoto, K.; Mingqing, W.

    1997-01-01

    Thirty samples from a limestone stratum across the Permian-Triassic (P-Tr) boundary layer in China were analyzed for 30 elements by instrumental neutron activation analysis, wavelength dispersive X-ray fluorescence and ICP-MS, and also for mineral compositions with a powder X-ray diffractometer. The depth profile was found to indicate a sudden change of elemental and mineral compositions across the P-Tr boundary. Also the profile showed several peaks in elemental concentrations in the lower Permian layered samples as well as in the overlying Triassic strata, which are associated with the change of mineral compositions. Elemental profiles were found to be classified into 4 groups and to give some insights in the geochemical records. Ir is far less abundant (0.1 ppt) compared with that of the K-T boundaries (10 ppb), and the Ir/Co ratio is outside the K-T and Cl chondrite trends. This change of elementary profile is suggestive of the internal causes rather than the external ones such as an asteroid impact for the mass extinction at the P-Tr boundary. (author)

  20. The youngest trigonotarbid Permotarbus schuberti n. gen., n. sp. from the Permian Petrified Forest of Chemnitz in Germany

    Directory of Open Access Journals (Sweden)

    J. A. Dunlop

    2013-08-01

    Full Text Available A new trigonotarbid (Arachnida: Trigonotarbida is described as Permotarbus schuberti n. gen., n. sp. from the Early Permian Petrified Forest (Rotliegend of Chemnitz in Saxony (Germany. At ca. 290 Ma it represents the youngest record of this extinct arachnid order discovered to date. Its familial affinities are uncertain, but may lie close to the Aphantomartidae. The distribution of the trigonotarbid genera through time is summarised, together with a list of their seventy-seven fossil-yielding localities. Together they offer a broad overview of the group's fossil record, which is heavily biased towards the Moscovian Stage (ca. 307–312 Ma of the Late Carboniferous in Europe and North America. This is due in no small part to numerous localities associated with coal mining districts, and trigonotarbids are found less frequently after this stage. While it is tempting to associate this with biological events – such as a putative "Carboniferous Rainforest Collapse" dating to ca. 305 Ma – it is difficult to differentiate the effects of genuine extinction patterns from artefacts caused by fewer appropriate localities in the economically less relevant latest Carboniferous and Early Permian strata. Nevertheless, trigonotarbids became extinct at some point after the Early Permian and loss of the Coal Measures forests remains one of the most likely possible causes. doi:10.1002/mmng.201300012

  1. Kerogen morphology and geochemistry at the Permian-Triassic transition in the Meishan section, South China: Implication for paleoenvironmental variation

    Science.gov (United States)

    Sawada, Ken; Kaiho, Kunio; Okano, Kazuki

    2012-08-01

    Detailed fluorescent microscopic observations and organic geochemical analyses for insoluble sedimentary organic matter (kerogens) are conducted on the end-Permian to earliest Triassic sediments in the Meishan section A of South China. The main objectives of the present study are to reconstruct variations of marine and terrestrial environments, and to evaluate bulk characteristics of terrestrial input in the palaeo-Tethys ocean for the Permian-Triassic boundary (PTB). Most of kerogens in the Meishan section are mainly composed of marine algae-derived amorphous organic matter, while terrestrial plant-derived amorphous organic matter is remarkably dominant in the mass extinction horizon reported previously. The relative abundances of marine organic matter may vary depending on marine production rather than terrestrial input in the palaeo-Tethys associated with changing terrestrial vegetation. We also identified aromatic furans as major compounds in kerogen pyrolysate of all layers. It is possible that sources of aromatic furans with alkyl group, fungi and lichen, proliferated as disaster biota in terrestrial ecosystem through the PTB. Higher abundances of herbaceous organic matter are observed in the layers above the mass extinction horizon. However, the conifer biomarker retene can be identified in kerogen pyrolysates of all layers. These results imply that the productions of herbaceous plants increased as dominant pioneer biota in early stage of recovery for terrestrial ecosystem after its collapse, but also that woody plant potentially continued to be produced in land area throughout the end-Permian and earliest-Triassic.

  2. Permian Triassic palynofloral transition in Chintalapudi area, Godavari Graben, Andhra Pradesh, India

    Science.gov (United States)

    Jha, Neerja; Chary, M. Basava; Aggarwal, Neha

    2012-10-01

    The entire 606 m-thick sedimentary sequence in borecore MCP-7 from Chintalapudi area, Chintalapudi sub-basin has been lithologically designated as Kamthi Formation. However, the palynological investigation revealed five distinct palynoassemblages, which essentially fall under two groups, one group (Palynoassemblage-I, II and III) having dominance of striate disaccates along with presence of some stratigraphically significant taxa, belongs to Late Permian (Raniganj) palynoflora, while the other group (Palynoassemblages IV and V) shows sharp decline in percentage of characteristic taxa of first group, i.e., striate disaccates, and consequent rise or dominance of taeniate and cingulate cavate spores, belongs to Early Triassic (Panchet) palynoflora. Palynoassemblage-I, II and III (Group I) are characterized by dominance of striate disaccates chiefly, Striatopodocarpites spp. and Faunipollenites spp. along with presence of rare but stratigraphically significant taxa, viz., Gondisporites raniganjensis, Falcisporites nuthaliensis, Klausipollenites schaubergeri, Chordasporites sp., Striomonosaccites, ovatus, Crescentipollenites multistriatus, Verticipollenites debiles, Strotersporites crassiletus, Guttulapollenites hannonicus, G. gondwanensis, Hamiapollenites insolitus, Corisaccites alutus, Lunatisporites ovatus, Weylandites spp. and Vitreisporites pallidus. Palynoassemblage-I is distinguished by significant presence of Densipollenites spp. while Palynoassemblage-II shows significant presence of Crescentipollenites spp. and Palynoassemblage-III differs from the above two assemblages in having significant presence of Guttulapollenites hannonicus. Palynoassemblage-IV (Group II) is characterized by high percentage of taeniate disaccates chiefly Lunatisporites spp., while Palynoassemblage-V (Group II) is characterized by cingulate-cavate trilete spores chiefly, Lundbladispora spp. and Densoisporites spp. Striate disaccates show a sharp decline in these two assemblages. In

  3. The earliest Permian shark fossils from Texas and their implications for later marine faunas

    Science.gov (United States)

    Shell, R.; Ciampaglio, C. N.

    2017-12-01

    Complex marine vertebrate faunas from lower Permian rocks are incredibly rare. Recent research suggests that the composition of what few communities can be found varied wildly, especially in regard to the presence or absence of Hybodontiform sharks. Early Permian marine faunas in Texas are generally richer in Hybodont sharks than similarly aged communities in Russia and Bolivia, but the cause of this variation is unknown. A fossil hybodont spine fragment from just above the Pennsylvanian/Permian boundary in Texas, however, suggests that that regional climatic events allowed Hybodont sharks to migrate into the Permian Basin at the outset of the Permian itself. As the Basin evolved tectonically and sedimentologically, these sharks likely evolved to fill new niches as they opened up- which may have resulted in the increased number of Hybodont species in the Permian of Texas: a major factor to consider in the faunal evolution of the Western Interior Seaway during the Mesozoic and beyond.

  4. Environmental mutagenesis during the end-Permian ecological crisis.

    Science.gov (United States)

    Visscher, Henk; Looy, Cindy V; Collinson, Margaret E; Brinkhuis, Henk; van Konijnenburg-van Cittert, Johanna H A; Kürschner, Wolfram M; Sephton, Mark A

    2004-08-31

    During the end-Permian ecological crisis, terrestrial ecosystems experienced preferential dieback of woody vegetation. Across the world, surviving herbaceous lycopsids played a pioneering role in repopulating deforested terrain. We document that the microspores of these lycopsids were regularly released in unseparated tetrads indicative of failure to complete the normal process of spore development. Although involvement of mutation has long been hinted at or proposed in theory, this finding provides concrete evidence for chronic environmental mutagenesis at the time of global ecological crisis. Prolonged exposure to enhanced UV radiation could account satisfactorily for a worldwide increase in land plant mutation. At the end of the Permian, a period of raised UV stress may have been the consequence of severe disruption of the stratospheric ozone balance by excessive emission of hydrothermal organohalogens in the vast area of Siberian Traps volcanism. Copyright 2004 The National Academy of Sciencs of the USA

  5. Saving radiation dose and contrast media in intravenous digital subtraction angiography by use of bolus chasing

    International Nuclear Information System (INIS)

    Rueckforth, J.; Schuermann, K.; Vorwerk, D.; Guenther, R.W.

    1998-01-01

    Purpose: This study evaluates the dose area product, the amount of contrast media and the examination quality of the bolus chasing technique compared to the single-step technique in intravenous digital subtraction angiography. Material and Methods: 15 examinations each with bolus chasing and single-step technique were compared. The dose area product and the volume of contrast media were recorded. The examination quality was scored by two examiners. Results: With bolus chasing the volume of the administered contrast media could be decreased on average by 114 ml (43%). The difference between the dose area product of bolus chasing (722 dGy/cm 2 ) and single-step technique (1910 dGy/cm 2 ) was significant. No significant difference in examination quality was found. Conclusions: The intravenous bolus chasing technique is a practicable method. Compared to the single-step technique it allows a remarkable dose reduction and a low consumption of contrast media without restriction of examination quality. (orig.) [de

  6. Permian Triassic palynofloral transition in Chintalapudi area ...

    Indian Academy of Sciences (India)

    The entire 606 m-thick sedimentary sequence in borecore MCP-7 from Chintalapudi area, Chintalapudi sub-basin has been lithologically designated as Kamthi Formation. However, the palynological investigation revealed five distinct palynoassemblages, which essentially fall under two groups, one group ...

  7. GammeV and GammeV-CHASE

    International Nuclear Information System (INIS)

    Wester, W.

    2011-01-01

    Physics beyond the Standard Model might include Weakly Interacting Slim Particles (WISPs) that address questions such as what is the nature of dark matter or even shed insight into the underlying nature of dark energy. WISPs are a general class of particles that include axions, axion-like particles, hidden sector photons, milli-charged particles, chameleons, etc. The GammeV (Gamma to milli-eV) experiment originated in 2007 in order to test a positive anomalous axion-like particle interpretation of the PVLAS experiment which was not evident in subsequent data. The experiment was also motivated as it was realized that the milli-eV scale appears naturally in a see-saw between the electroweak and Planck scales, neutrino mass differences, the dark energy density, and the possible mass for certain dark matter candidates. GammeV was first to exclude both a scalar and pseudoscalar axion-like particle interpretation of the anomalous PVLAS result setting a limit of around 3.1 x 10 -7 GeV -1 on the coupling to photons for low mass axion-like particles. It has also been found that the parameter space of a variety of other WISP candidates is both largely unexplored and is accessible by modest experiments employing lasers and possibly accelerator magnets. GammeV data has also been used to set limits on possible hidden sector photons. Further work by the GammeV team has focused on a reconfiguration of the apparatus to be sensitive to possible chameleon particles. Chameleons are scalar (or pseudoscalar) particles that couple to the stress energy tensor in a potential such that their properties depend on their environment. In particular, a chameleon acquires an effective mass which increases with local matter density, ρ. For a certain class of such potentials, the chameleon field has properties that might explain dark energy. GammeV set the first limits on the coupling of chameleons to photons. A dedicated follow-up experiment, GammeV-CHASE, (CHameleon Afterglow SEarch), has also

  8. Short-term exposure to repeated chasing stress does not induce habituation in Senegalese sole, Solea senegalensis

    DEFF Research Database (Denmark)

    Conde-Sieira, Marta; Valente, Luisa M.P.; Hernandez-Perez, Juan

    2018-01-01

    Animals can habituate to certain repeated stressors and reduce the physiological response that such stressor evoked initially. Studies related to stress habituation in fish are scarce and the available data differ depending on the species and on the type, duration and severity of the stressor...... no significant changes in serotonergic activity. However, incremented serotonergic activity was detected in fish previously trained. Furthermore, dopaminergic activity decreased in diurnal trained and nocturnal trained groups with respect to ST/naïve fish. Crh expression in hypothalamus was higher in ST...... for the animals to habituate, indicating that repeated chasing within short periods should be avoided when manipulating fish in order to keep proper welfare conditions in this species....

  9. Permian Triassic palynofloral transition in Chintalapudi area ...

    Indian Academy of Sciences (India)

    Palynoassemblage-IV (Group II) is characterized by high percentage of taeniate disaccates chiefly. Lunatisporites spp. .... to the age assignment and identification of dis- ..... us pollenites. Platy saccus. Sch eurin gip olle nites. Ib is porites. In ap ertu ro pollen ites ..... graphic classification based on microfloras, macrofloras,.

  10. Pre-Alleghenian (Pennsylvanian-Permian) hydrocarbon emplacement along Ordovician Knox unconformity, eastern Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, F.M.; Kesler, S.E.

    1989-03-01

    Cores taken during exploration for Mississippi Valley-type lead and zinc ores in the Mascot-Jefferson City zinc district of eastern Tennessee commonly contain hydrocarbon residues in carbonate rocks of the Knox Group immediately below the Lower Ordovician Knox unconformity. The location and number of these residue-bearing strata reveal information about the Paleozoic history of hydrocarbon emplacement in the region. Contour maps, generated from nearly 800 holes covering more than 20 km/sup 2/, indicate that zones with elevated organic content in the uppermost 30 m of the Lower Ordovician Mascot Dolomite show a strong spatial correlation with Middle Ordovician paleotopographic highs. These same zones show no spatial association with present-day structural highs, which were formed during Pennsylvanian-Permian Alleghenian tectonism. This suggests that the physical entrapment of hydrocarbons migrating through the upper permeable units of the Mascot must have occurred prior to the principal tectonism of the Alleghenian orogeny. 7 figures, 1 table.

  11. The paleoclimate of the Kazanian (early Late Permian) world

    Energy Technology Data Exchange (ETDEWEB)

    Moore, G.T. (Chevron Oil Field Research Co., La Habra, CA (USA)); Peoples, C.J. (Texas A and M Univ., College Station (USA))

    1990-05-01

    The Kazanian (early Late Permian, 258-253 m.y.) marked the onset of a unique interval in the Phanerozoic, distinguished by a classic end-member case of continental assembly, the megacontinent Pangaea. Compilation of biostratigraphic and lithofacies data indicate a warm, extensively arid world, largely ice free, and characterized by the onset of atmospheric conditions that were exceedingly stressful to the biosphere, the worst of the eon. Using Chevron's version of the Community Climate model, the authors report here on two Kazanian paleoclimate seasonal simulations, one using 200 ppm CO{sub 2} and the other with 2,000 ppm CO{sub 2}. The authors consider the knowledge of plate assembly back to the Permian accurate enough to allow employment of a seasonal model. Simulation of a warmer Earth with an elevated greenhouse effect (modeled as CO{sub 2}) fits the observed geology and isotope signals. The increased CO{sub 2} experiment warmed the entire planet with the greatest increases north of 50{degree} latitude and least changes in the tropics. The warming caused the poleward retreat of sea ice in both hemispheres. Precipitation and evaporation increased, but runoff was confined to areas of very intense rainfall. Monsoons are limited to the southern hemisphere, associated with the western Tethys sea and the eastern equatorial Panthalassa ocean. Extreme southeastern Pangaea (northern Australia) was a focus of precipitation throughout the year. Precipitation occurred in the higher latitudes (50-55{degree}) on the western coast, of Pangaea where storm tracks make landfall. High evaporation rates characterized the restricted Permian (US), Zechstein, and Perm (Soviet Union) basins, a time of evaporite, deposition. Interior Pangaea at middle to high latitudes endured frigid winters ({minus}40{degree}C) and torrid summers (60{degree}C).

  12. Permian Tethyan Fusulinina from the Kenai Peninsula, Alaska

    Science.gov (United States)

    Stevens, C.H.; Davydov, V.I.; Bradley, D.

    1997-01-01

    Two samples from a large, allochthonous limestone block in the McHugh Complex of the Chugach terrane on the Kenai Peninsula, Alaska, contain species of 12 genera of Permian Fusulinina including Abadehella, Kahlerina, Pseudokahlerina?, Nankinella, Codonofusiella, Dunbarula, Parafusulina?, Chusenella, Verbeekina, Pseudodoliolina, Metadoliolina?, Sumatrina?, and Yabeina, as well as several other foraminiferans and one alga. The assemblage of fusulinids is characteristically Tethyan, belonging to the Yabeina archaica zone of early Midian (late Wordian) age. Similar faunas are known from the Pamirs, Transcaucasia, and Japan, as well as from allochthonous terranes in British Columbia, northwestern Washington, and Koryakia in eastern Siberia.

  13. Engaging Experiential Service Learning through a Co-Curricular Club: The Chase Charlie Races

    Science.gov (United States)

    Judge, Lawrence W.; Pierce, David; Petersen, Jeffrey; Bellar, David; Wanless, Elizabeth; Gilreath, Erin; Simon, Laura

    2011-01-01

    The efficacy of the "Chase Charlie Races" (an experiential learning activity) was demonstrated via program assessment. This was achieved via post-event evaluations of race participants and student club members, and with fitness assessments of 76 elementary students who participated in an eight-week training program. Paired sample t-tests revealed…

  14. Chase and NYANA: A Partnership To Remove Barriers to Job Performance 1993-94. Final Report.

    Science.gov (United States)

    Auerbach, Charles

    A workplace literacy program implemented cooperatively by the New York Association for New Americans, Inc. (NYANA) and Chase Manhattan Bank is reported. The federally-funded project provided individualized communication workplace behavior and skills training in English as a Second Language for 30 limited-English-proficient bank employees working…

  15. A high resolution magnetostratigraphic profile across the Permian-Triassic boundary in the Southern Sydney Basin, eastern Australia

    Science.gov (United States)

    Belica, M. E.; Tohver, E.; Nicoll, R.; Denyszyn, S. W.; Pisarevsky, S.; George, A. D.

    2016-12-01

    The Permian-Triassic boundary (PTB) is associated with the largest mass extinction in Phanerozoic geologic history. Despite several decades of intense study, there is ongoing debate regarding the exact timing of extinction and the global correlation of marine and terrestrial P-T sections. The terrestrial record is hampered by a lack of index fossils; however, magnetostratigraphy offers an opportunity for correlation because it relies on the global synchronicity of magnetic reversals. A magnetostratigraphic profile across the Permian-Triassic boundary has been obtained from a stratigraphically continuous terrestrial section in the Southern Sydney Basin of eastern Australia. The 60 m section is located within the Narrabeen Group, which consists of fluvial to lacustrine sandstones and mudstones. Paleomagnetic samples were collected at one meter intervals to determine a detailed reversal record. Samples were stepwise thermally demagnetized to isolate a primary remanence, and magnetic susceptibility was measured in the field at 30 cm intervals with values ranging from -0.047-2.50 (10-3 SI units). Three normal and three reverse magnetozones were detected after removal of a low temperature overprint, and the results show good agreement with the Global Magnetic Polarity Timescale as well as marine Permian-Triassic sections where the PTB is well constrained. Furthermore, a reverse polarity subchron has been identified within the normal magnetozone spanning the PTB similar to results published from the Netherlands and China. The magnetic stratigraphy suggests that the Narrabeen Group was deposited during the late Changhsingian to early Induan, and provides a revised placement of the PTB in the lower Wombarra Claystone. Integration of the magnetostratigraphy with existing isotopic datasets suggests that the terrestrial extinction in eastern Australia occurred 7.5 m below the PTB in the Changhsingian Coalcliff Sandstone. A tuff within a coal seam underlying the Coalcliff

  16. The Tunas Formation (Permian) in the Sierras Australes foldbelt, east central Argentina: evidence for syntectonic sedimentation in a foreland basin

    Science.gov (United States)

    Lopez-Gamundi, O. R.; Conaghan, P. J.; Rossello, E. A.; Cobbold, P. R.

    1995-04-01

    The Tunas Formation, extensively exposed in the Sierras Australes foldbelt of eastern central Argentina, completes the sedimentation of the Gondwanan (Late Carboniferous-Permian) sequence, locally known as the Pillahuincó Group. The underlying units of the Group show an integrated depositional history which can be explained in terms of glaciomarine sedimentation (Sauce Grande Formation) and postglacial transgression (Piedra Azul and Bonete Formations). This succession also has a rather uniform quartz-rich, sand-sized composition indicative of a cratonic provenance from the Tandilia Massif to the northeast. Early to Late Permian deformation folded and thrusted the southwestern basin margin (Sierras Australes) and triggered the deposition of a 1,500 m — thick, synorogenic prograding wedge, the Tunas Formation, in the adjacent foreland basin (Sauce Grande or Claromecó Basin). Sandstone detrital modes for the Tunas deposits show moderate to low contents of quartz and abundant lithics, mostly of volcanic and metasedimentary origin. Paleocurrents are consistently from the SW. Tuffs interbedded with sandstones in the upper half of Tunas Formation (Early — early Late? Permian) are interpreted as being derived from volcanic glass-rich tuffs settled in a body of water. Extensive rhyolitic ignimbrites and consanguineous airborne tuffaceous material erupted in the northern Patagonian region during that period. The age constraints and similarities in composition between these volcanics and the tuffaceous horizons present in the Sauce Grande, Parana and Karoo Basins suggest a genetic linkage between these two episodes. The intimate relationship between volcanic activity inboard of the paleo-Pacific margin, deformation in the adjacent orogenic belt and subsidence and sedimentation in the contiguous foreland basin constitutes a common motif in the Sauce Grande and Karoo Basins of southwestern Gondwana.

  17. Eopolydiexodina (Middle Permian giant fusulinids) from Afghanistan: Biometry, morphometry, paleobiogeography, and end-Guadalupian events

    Science.gov (United States)

    Colpaert, Clémentine; Monnet, Claude; Vachard, Daniel

    2015-04-01

    The most spectacular macroevolutionary trend presented by the genera of schwagerinoid fusulinids, during the Pennsylvanian -Permian, is an enormous increase in size, which culminated in the Middle Permian with Eopolydiexodina. However, this potential major biogeographic marker, during the Kubergandian-early Midian time interval, is as yet hampered by its poor taxonomic characterization. Hence, Eopolydiexodina is revised here using biometric and morphometric methods applied to large collections from Afghanistan and selected taxa in the literature. These multivariate analyses consist of classical linear test parameters, as well as new area parameters acquired by computer image analysis. The Afghan species are re-defined, and some other species, occasionally described as Cimmerian, are re-discussed. These methods, combined with classical morphological analyses, also permit to conclude that the largest Eopolydiexodina of Afghanistan are microspheric specimens (probably agamonts) of E. afghanensis and E. bithynica. Two megalospheric groups of individuals (probably gamonts and schizonts) are represented in both species, as well as in E. persica and E. darvasica. Due to this presence of gamonts, agamonts and schizonts in several species, Eopolydiexodina is probably the oldest identified trimorphic genus among the large benthic foraminifers. Biostratigraphically, Eopolydiexodina appears restricted to the late Kubergandian to early Midian. The associated Afghan fusulinids (Dunbarula, Kahlerina, Afghanella, Yangchienia, Sumatrina, and Codonofusiella) allow proposing an accurate biostratigraphy of the Eopolydiexodina species in the Murgabian-Midian boundary interval. Paleobiogeographically, Eopolydiexodina was essentially located in the Laurentian and Perigondwanan borders of the Tethys. The possible presence of Eopolydiexodina in the Cimmerian Continent and in some regions of China has never been irrefutably demonstrated. This paleobiological revision of Eopolydiexodina and

  18. Dalhart's only Permian field gets best oil well

    International Nuclear Information System (INIS)

    Land, R.

    1992-01-01

    This paper reports that activity is picking up in Proctor Ranch oil field in the northwestern Texas panhandle, the only Permian producing field in the lightly drilled Dalhart basin. During the last 2 1/2 months, the field has a new operator and a new producing well, the best of five drilled since discovery in 1990. Corlena Oil Co., Amarillo, acquired the field from McKinney Oil Co. in May and tested its first well in early July. The 1-64 Proctor, 18 miles west of Channing, pumped at rates as high as 178 bd of oil and 6 b/d of water from Permian Wolfcamp dolomite perforations at 4,016-29 ft. Corlena plans to drill another well south of the field soon. The lease requires that the next well be spudded by early November. The field appears to be combination structural-stratigraphic trap in which the dolomite pinches out against the Bravo Domes-Oldham nose to the west

  19. Flourishing ocean drives the end-Permian marine mass extinction.

    Science.gov (United States)

    Schobben, Martin; Stebbins, Alan; Ghaderi, Abbas; Strauss, Harald; Korn, Dieter; Korte, Christoph

    2015-08-18

    The end-Permian mass extinction, the most severe biotic crisis in the Phanerozoic, was accompanied by climate change and expansion of oceanic anoxic zones. The partitioning of sulfur among different exogenic reservoirs by biological and physical processes was of importance for this biodiversity crisis, but the exact role of bioessential sulfur in the mass extinction is still unclear. Here we show that globally increased production of organic matter affected the seawater sulfate sulfur and oxygen isotope signature that has been recorded in carbonate rock spanning the Permian-Triassic boundary. A bifurcating temporal trend is observed for the strata spanning the marine mass extinction with carbonate-associated sulfate sulfur and oxygen isotope excursions toward decreased and increased values, respectively. By coupling these results to a box model, we show that increased marine productivity and successive enhanced microbial sulfate reduction is the most likely scenario to explain these temporal trends. The new data demonstrate that worldwide expansion of euxinic and anoxic zones are symptoms of increased biological carbon recycling in the marine realm initiated by global warming. The spatial distribution of sulfidic water column conditions in shallow seafloor environments is dictated by the severity and geographic patterns of nutrient fluxes and serves as an adequate model to explain the scale of the marine biodiversity crisis. Our results provide evidence that the major biodiversity crises in Earth's history do not necessarily implicate an ocean stripped of (most) life but rather the demise of certain eukaryotic organisms, leading to a decline in species richness.

  20. Late Carboniferous and Early Permian algal microflora (Liuzhou, South China)

    Energy Technology Data Exchange (ETDEWEB)

    Li Chun (Nanjing Inst. of Geology and Paleontology, Nanjing (China)); Mamet, B. (Montreal Univ., PQ (Canada))

    1993-03-01

    Paleozoic algae are important contributors to the formation of carbonate sediments. A study was conducted to compare an Upper Carboniferous-Lower Permian carbonate succession of South China with what is generally observed in the Tethys Sea and North America. The sequence studied was in the Maping Limestone at the Loutishan section in Liuzhou, with some additional information derived from the Maping Limestone at Shangxinping and from the Chuanshan Limestone at Yuhuangshan and in the Nanjing Hills. In the Late Carboniferous, the beresellid algae are important builders and the Tubiphytes-Archaeolithophyllum community is locally replaced by a Tubiphytes-Ungdarella association. Early Permian oncolites were formed by complex Osagia, then by Esmerella. The Asselian Sphaeroschwagerina fauna is underlined by the outburst of epimastoporid dasycladales and phylloid Anchicodiaceae. Microcodium is observed at the contact of the Sphaeroschwagerina moelleri/sphaerica Zones. The overlying and paraconformable Chihsia Limestone is characterized by a Gymnocodium-Gyroporella-Mizzia flora. In most cases, the base of the fusulinid zones, therefore, coincides with an important local floristic change. 72 refs., 4 figs.

  1. Restoration of marine ecosystems following the end-Permian mass extinction: pattern and dynamics

    Science.gov (United States)

    Chen, Z.

    2013-12-01

    Life came closest to complete annihilation during the end-Permian mass extinction (EPME). Pattern and cause of this great dying have long been disputed. Similarly, there is also some debate on the recovery rate and pattern of marine organisms in the aftermath of the EPME. Some clades recovered rapidly, within the first 1-3 Myr of the Triassic. For instance, foraminiferal recovery began 1 Myr into the Triassic and was not much affected by Early Triassic crises. Further, some earliest Triassic body and trace fossil assemblages are also more diverse than predicted. Others, ie. Brachiopods, corals etc., however, did not rebound until the Middle Triassic. In addition, although ammonoids recovered fast, reaching a higher diversity by the Smithian than in the Late Permian, much of this Early Triassic radiation was within a single group, the Ceratitina, and their morphological disparity did not expand until the end-Spathian. Here, I like to broaden the modern ecologic network model to explore the complete trophic structure of fossilized ecosystems during the Permian-Triassic transition as a means of assessing the recovery. During the Late Permian and Early Triassic, primary producers, forming the lowest trophic level, were microbes. The middle part of the food web comprises primary and meso-consumer trophic levels, the former dominated by microorganisms such as foraminifers, the latter by opportunistic communities (i.e. disaster taxa), benthic shelly communities, and reef-builders. They were often consumed by invertebrate and vertebrate predators, the top trophic level. Fossil record from South China shows that the post-extinction ecosystems were degraded to a low level and typified by primary producers or opportunistic consumers, which are represented by widespread microbialites or high-abundance, low-diversity communities. Except for some opportunists, primary consumers, namely foraminifers, rebounded in Smithian. Trace-makers recovered in Spathian, which also saw

  2. Contrasting microbial community changes during mass extinctions at the Middle/Late Permian and Permian/Triassic boundaries

    Science.gov (United States)

    Xie, Shucheng; Algeo, Thomas J.; Zhou, Wenfeng; Ruan, Xiaoyan; Luo, Genming; Huang, Junhua; Yan, Jiaxin

    2017-02-01

    Microbial communities are known to expand as a result of environmental deterioration during mass extinctions, but differences in microbial community changes between extinction events and their underlying causes have received little study to date. Here, we present a systematic investigation of microbial lipid biomarkers spanning ∼20 Myr (Middle Permian to Early Triassic) at Shangsi, South China, to contrast microbial changes associated with the Guadalupian-Lopingian boundary (GLB) and Permian-Triassic boundary (PTB) mass extinctions. High-resolution analysis of the PTB crisis interval reveals a distinct succession of microbial communities based on secular variation in moretanes, 2-methylhopanes, aryl isoprenoids, steranes, n-alkyl cyclohexanes, and other biomarkers. The first episode of the PTB mass extinction (ME1) was associated with increases in red algae and nitrogen-fixing bacteria along with evidence for enhanced wildfires and elevated soil erosion, whereas the second episode was associated with expansions of green sulfur bacteria, nitrogen-fixing bacteria, and acritarchs coinciding with climatic hyperwarming, ocean stratification, and seawater acidification. This pattern of microbial community change suggests that marine environmental deterioration was greater during the second extinction episode (ME2). The GLB shows more limited changes in microbial community composition and more limited environmental deterioration than the PTB, consistent with differences in species-level extinction rates (∼71% vs. 90%, respectively). Microbial biomarker records have the potential to refine our understanding of the nature of these crises and to provide insights concerning possible outcomes of present-day anthropogenic stresses on Earth's ecosystems.

  3. High precision time calibration of the Permian-Triassic boundary mass extinction event in a deep marine context

    Science.gov (United States)

    Baresel, Björn; Bucher, Hugo; Brosse, Morgane; Bagherpour, Borhan; Schaltegger, Urs

    2015-04-01

    To construct a revised and high resolution calibrated time scale for the Permian-Triassic boundary (PTB) we use (1) high-precision U-Pb zircon age determinations of a unique succession of volcanic ash layers interbedded with deep water fossiliferous sediments in the Nanpanjiang Basin (South China) combined with (2) accurate quantitative biochronology based on ammonoids, conodonts, radiolarians, and foraminifera and (3) tracers of marine bioproductivity (carbon isotopes) across the PTB. The unprecedented precision of the single grain chemical abrasion isotope-dilution thermal ionization mass spectrometry (CA-ID-TIMS) dating technique at sub-per mil level (radio-isotopic calibration of the PTB at the groups of processes. Using these alignments allows (1) positioning the PTB in different depositional setting and (2) solving the age contradictions generated by the misleading use of the first occurrence (FO) of the conodont Hindeodus parvus, whose diachronous first occurrences are arbitrarily used for placing the base of the Triassic. This new age framework provides the basis for a combined calibration of chemostratigraphic records with high-resolution biochronozones of the Late Permian and Early Triassic. Here, we present new single grain U-Pb zircon data of volcanic ash layers from two deep marine sections (Dongpan and Penglaitan) revealing stratigraphic consistent dates over several volcanic ash layers bracketing the PTB. These analyses define weighted mean 206Pb/238U ages of 251.956±0.033 Ma (Dongpan) and 252.062±0.043 Ma (Penglaitan) for the last Permian ash bed. By calibration with detailed litho- and biostratigraphy new U-Pb ages of 251.953±0.038 Ma (Dongpan) and 251.907±0.033 Ma (Penglaitan) are established for the onset of the Triassic.

  4. Early Triassic alternative ecological states driven by anoxia, hyperthermals, and erosional pulses following the end-Permian mass extinction

    Science.gov (United States)

    Pietsch, C.; Petsios, E.; Bottjer, D. J.

    2015-12-01

    The end-Permian mass extinction, 252 million years ago, was the most devastating loss of biodiversity in Earth's history. Massive volcanic eruptions of the Siberian Traps and the concurrent burning of coal, carbonate, and evaporite deposits emplaced greenhouse and toxic gasses. Hyperthermal events of the surface ocean, up to 40°C, led to reduced gradient-driven ocean circulation which yielded extensive equatorial oxygen minimum zones. Today, anthropogenic greenhouse gas production is outpacing carbon input modeled for the end-Permian mass extinction, which suggests that modern ecosystems may yet experience a severe biotic crisis. The Early Triassic records the 5 million year aftermath of the end-Permian mass extinction and is often perceived as an interval of delayed recovery. We combined a new, high resolution carbon isotope record, sedimentological analysis, and paleoecological collections from the Italian Werfen Formation to fully integrate paleoenvironmental change with the benthic ecological response. We find that the marine ecosystem experienced additional community restructuring events due to subsequent hyperthermal events and pulses of erosion. The benthic microfauna and macrofauna both contributed to disaster communities that initially rebounded in the earliest Triassic. 'Disaster fauna' including microbialites, microconchids, foraminifera, and "flat clams" took advantage of anoxic conditions in the first ~500,000 years, dominating the benthic fauna. Later, in the re-oxygenated water column, opportunistic disaster groups were supplanted by a more diverse, mollusc-dominated benthic fauna and a complex ichnofauna. An extreme temperature run-up beginning in the Late Dienerian led to an additional hyperthermal event in the Late-Smithian which co-occurred with increased humidity and terrestrial run-off. Massive siliciclastic deposits replaced carbonate deposition which corresponds to the infaunalization of the benthic fauna. The disaster taxa dominated

  5. Bringing Dicynodonts Back to Life: Paleobiology and Anatomy of a New Emydopoid Genus from the Upper Permian of Mozambique

    Science.gov (United States)

    Júnior, Luís C.; Angielczyk, Kenneth D.; Martins, Gabriel G.; Martins, Rui M. S.; Chaouiya, Claudine; Beckmann, Felix; Wilde, Fabian

    2013-01-01

    Dicynodontia represent the most diverse tetrapod group during the Late Permian. They survived the Permo-Triassic extinction and are central to understanding Permo-Triassic terrestrial ecosystems. Although extensively studied, several aspects of dicynodont paleobiology such as, neuroanatomy, inner ear morphology and internal cranial anatomy remain obscure. Here we describe a new dicynodont (Therapsida, Anomodontia) from northern Mozambique: Niassodon mfumukasi gen. et sp. nov. The holotype ML1620 was collected from the Late Permian K5 formation, Metangula Graben, Niassa Province northern Mozambique, an almost completely unexplored basin and country for vertebrate paleontology. Synchrotron radiation based micro-computed tomography (SRµCT), combined with a phylogenetic analysis, demonstrates a set of characters shared with Emydopoidea. All individual bones were digitally segmented allowing a 3D visualization of each element. In addition, we reconstructed the osseous labyrinth, endocast, cranial nerves and vasculature. The brain is narrow and the cerebellum is broader than the forebrain, resembling the conservative, “reptilian-grade” morphology of other non-mammalian therapsids, but the enlarged paraflocculi occupy the same relative volume as in birds. The orientation of the horizontal semicircular canals indicates a slightly more dorsally tilted head posture than previously assumed in other dicynodonts. In addition, synchrotron data shows a secondary center of ossification in the femur. Thus ML1620 represents, to our knowledge, the oldest fossil evidence of a secondary center of ossification, pushing back the evolutionary origins of this feature. The fact that the specimen represents a new species indicates that the Late Permian tetrapod fauna of east Africa is still incompletely known. PMID:24324653

  6. Bringing dicynodonts back to life: paleobiology and anatomy of a new emydopoid genus from the Upper Permian of Mozambique.

    Directory of Open Access Journals (Sweden)

    Rui Castanhinha

    Full Text Available Dicynodontia represent the most diverse tetrapod group during the Late Permian. They survived the Permo-Triassic extinction and are central to understanding Permo-Triassic terrestrial ecosystems. Although extensively studied, several aspects of dicynodont paleobiology such as, neuroanatomy, inner ear morphology and internal cranial anatomy remain obscure. Here we describe a new dicynodont (Therapsida, Anomodontia from northern Mozambique: Niassodon mfumukasi gen. et sp. nov. The holotype ML1620 was collected from the Late Permian K5 formation, Metangula Graben, Niassa Province northern Mozambique, an almost completely unexplored basin and country for vertebrate paleontology. Synchrotron radiation based micro-computed tomography (SRµCT, combined with a phylogenetic analysis, demonstrates a set of characters shared with Emydopoidea. All individual bones were digitally segmented allowing a 3D visualization of each element. In addition, we reconstructed the osseous labyrinth, endocast, cranial nerves and vasculature. The brain is narrow and the cerebellum is broader than the forebrain, resembling the conservative, "reptilian-grade" morphology of other non-mammalian therapsids, but the enlarged paraflocculi occupy the same relative volume as in birds. The orientation of the horizontal semicircular canals indicates a slightly more dorsally tilted head posture than previously assumed in other dicynodonts. In addition, synchrotron data shows a secondary center of ossification in the femur. Thus ML1620 represents, to our knowledge, the oldest fossil evidence of a secondary center of ossification, pushing back the evolutionary origins of this feature. The fact that the specimen represents a new species indicates that the Late Permian tetrapod fauna of east Africa is still incompletely known.

  7. Appalachian Piedmont landscapes from the Permian to the Holocene

    Science.gov (United States)

    Cleaves, E.T.

    1989-01-01

    Between the Potomac and Susquehanna Rivers and from the Blue Ridge to the Fall Zone, landscapes of the Piedmont are illustrated for times in the Holocene, Late Wisconsin, Early Miocene, Early Cretaceous, Late Triassic, and Permian. Landscape evolution took place in tectonic settings marked by major plate collisions (Permian), arching and rifting (Late Triassic) and development of the Atlantic passive margin by sea floor spreading (Early Cretaceous). Erosion proceeded concurrently with tectonic uplift and continued after cessation of major tectonic activity. Atlantic Outer Continental Shelf sediments record three major erosional periods: (1) Late Triassic-Early Jurassic; (2) Late Jurassic-Early Cretaceous; and (3) Middle Miocene-Holocene. The Middle Miocene-Holocene pulse is related to neotectonic activity and major climatic fluctuations. In the Piedmont upland the Holocene landscape is interpreted as an upland surface of low relief undergoing dissection. Major rivers and streams are incised into a landscape on which the landforms show a delicate adjustment to rock lithologies. The Fall Zone has apparently evolved from a combination of warping, faulting, and differential erosion since Late Miocene. The periglacial environment of the Late Wisconsin (and earlier glacial epochs) resulted in increased physical erosion and reduced chemical weathering. Even with lowered saprolitization rates, geochemical modeling suggests that 80 m or more of saprolite may have formed since Late Miocene. This volume of saprolite suggests major erosion of upland surfaces and seemingly contradicts available field evidence. Greatly subdued relief characterized the Early Miocene time, near the end of a prolonged interval of tropical morphogenesis. The ancestral Susquehanna and Potomac Rivers occupied approximately their present locations. In Early Cretaceous time local relief may have been as much as 900 m, and a major axial river draining both the Piedmont and Appalachians flowed southeast

  8. An integrated perspective on the Permian-Triassic "Great Dying"

    Science.gov (United States)

    Algeo, T. J.

    2017-12-01

    The 252-Ma end-Permian mass extinction (EPME), marked by the loss of 90% of marine invertebrate species, was the largest biocrisis in Earth history. Intensive study of this "Great Dying" has led to major insights and a broad consensus regarding many aspects of this event. The ultimate trigger is regarded as eruption of the Siberian Traps Large Igneous Province (STLIP), which released large quantities of greenhouse gases (CO2 and CH4) and sulfate aerosols, triggering a catastrophic global warming of 10°C and acidification of both land surfaces and the surface ocean. On land, a massive die-off of vegetation led to a transient episode of rapid soil erosion and a longer-term increase in weathering rates linked to elevated temperatures. In the ocean, widespread anoxia developed concurrently with the EPME, triggered by ocean-surface warming that reduced dissolved oxygen solubility in seawater and that intensified vertical stratification. Expanded anoxia led to massive burial of organic matter and reduced sulfur, although the evidence for this is indirect (C, U and S isotopes); few organic-rich deposits of Early Triassic age have been found, suggesting that organic sedimentation occurred mainly on continental slopes or in the deep ocean. Other aspects of the end-Permian crisis remain under debate. For example, there is no consensus regarding changes in marine productivity levels in the aftermath of the EPME, which would have been stimulated by enhanced subaerial weathering but depressed by reduced overturning circulation-the evidence to date may favor localized positive and negative changes in productivity. Also under scrutiny is evidence for volcanic eruptions and environmental perturbations during the 100 kyr prior to the EPME, which are likely to have occurred but remain poorly dated and quantified. The greatest uncertainty, however, may surround the nature of the proximate kill mechanism(s) during the EPME. Many hypotheses have been advanced including mechanisms

  9. Preservation of Permian allanite within an Alpine eclogite facies shear zone at Mt Mucrone, Italy: Mechanical and chemical behaviour of allanite during mylonitization

    DEFF Research Database (Denmark)

    Cenki-Tok, Benedicte; Oliot, E.; Berger, Alfons

    2011-01-01

    This study addresses the mechanical and cehmical behavior of allanite during shear zone formation under high-pressure metamorphism. Understanding physico-chemical processes related to the retention or resetting of Pb isotopes in allanite during geological processes is essential for robust......, and they were thus chemically and mechanically shielded during Alpine mylonitization. In undeformed samples (8a and 8b), two populations of epidote group minerals were found. Allanite forms either coronas around Permianmonazite or individual grains with patchy zoning. Both types yield Permian ages (208Pb/232Th...... age: 291±5 Ma). On the other hand, grains of REE-rich clinozoisite of Cretaceous age are found in undeformed rocks. These grains appear as small fragments with embayed surface outlines and minute satellites or rims around Permian allanite. These (re)crystallized grains are Sr-rich and show mosaic...

  10. Peronosporomycetes (Oomycota from a Middle Permian permineralised peat within the Bainmedart Coal Measures, Prince Charles Mountains, Antarctica.

    Directory of Open Access Journals (Sweden)

    Ben J Slater

    Full Text Available The fossil record of Peronosporomycetes (water moulds is rather sparse, though their distinctive ornamentation means they are probably better reported than some true fungal groups. Here we describe a rare Palaeozoic occurrence of this group from a Guadalupian (Middle Permian silicified peat deposit in the Bainmedart Coal Measures, Prince Charles Mountains, Antarctica. Specimens are numerous and comprise two morphologically distinct kinds of ornamented oogonia, of which some are attached to hyphae by a septum. Combresomyces caespitosus sp. nov. consists of spherical oogonia bearing densely spaced, long, hollow, slender, conical papillae with multiple sharply pointed, strongly divergent, apical branches that commonly form a pseudoreticulate pattern under optical microscopy. The oogonia are attached to a parental hypha by a short truncated stalk with a single septum. Combresomyces rarus sp. nov. consists of spherical oogonia bearing widely spaced, hollow, broad, conical papillae that terminate in a single bifurcation producing a pair of acutely divergent sharply pointed branches. The oogonium bears a short truncate extension where it attaches to the parental hypha. We propose that similarities in oogonium shape, size, spine morphology and hyphal attachment between the Permian forms from the Prince Charles Mountains and other reported Peronosporomycetes from Devonian to Triassic strata at widely separated localities elsewhere in the world delimit an extinct but once cosmopolitan Palaeozoic to early Mesozoic branch of the peronosporomycete clade. We name this order Combresomycetales and note that it played an important role in late Palaeozoic and early Mesozoic peatland ecosystems worldwide.

  11. Fox Chase Cancer Center's Genitourinary Division: a national resource for research, innovation and patient care.

    Science.gov (United States)

    Uzzo, Robert G; Horwitz, Eric M; Plimack, Elizabeth R

    2016-04-01

    Founded in 1904, Fox Chase Cancer Center remains committed to its mission. It is one of 41 centers in the country designated as a Comprehensive Cancer Center by the National Cancer Institute, is a founding member of the National Comprehensive Cancer Network, holds the magnet designation for nursing excellence, is one of the first to establish a family cancer risk assessment program, and has achieved national distinction because of the scientific discoveries made there that have advanced clinical care. Two of its researchers have won Nobel prizes. The Genitourinary Division is nationally recognized and viewed as one of the top driving forces behind the growth of Fox Chase due to its commitment to initiating and participating in clinical trials, its prolific contributions to peer-reviewed publications and presentations at scientific meetings, its innovations in therapies and treatment strategies, and its commitment to bringing cutting-edge therapies to patients.

  12. Chasing losses in online poker and casino games: characteristics and game play of Internet gamblers at risk of disordered gambling.

    Science.gov (United States)

    Gainsbury, Sally M; Suhonen, Niko; Saastamoinen, Jani

    2014-07-30

    Disordered Internet gambling is a psychological disorder that represents an important public health issue due to the increase in highly available and conveniently accessible Internet gambling sites. Chasing losses is one of the few observable markers of at-risk and problem gambling that may be used to detect early signs of disordered Internet gambling. This study examined loss chasing behaviour in a sample of Internet casino and poker players and the socio-demographic variables, irrational beliefs, and gambling behaviours associated with chasing losses. An online survey was completed by 10,838 Internet gamblers (58% male) from 96 countries. The results showed that Internet casino players had a greater tendency to report chasing losses than poker players and gamblers who reported chasing losses were more likely to hold irrational beliefs about gambling and spend more time and money gambling than those who reported that they were unaffected by previous losses. Gamblers who played for excitement and to win money were more likely to report chasing losses. This study is one of the largest ever studies of Internet gamblers and the results are highly significant as they provide insight into the characteristics and behaviours of gamblers using this mode of access. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Behaviorism Makes Its Debut: A Review of Lattal and Chase's Behavior Theory and Philosophy

    OpenAIRE

    Zuriff, G.E

    2005-01-01

    Behavior Theory and Philosophy, masterfully edited by Lattal and Chase, is a collection of 21 papers by major behaviorists, presented and discussed at a conference on the intersection of philosophy and behavior analysis held at West Virginia University in 2000. The chapters in Part I are devoted to philosophy of science (causality, constructs, theory, explanation, reductionism) and the relations among behavior analysis and several contemporary philosophical movements (humanism, empiricism, pr...

  14. Composition and palaeogeographic position of the Early Permian Jambi flora from Sumatra

    NARCIS (Netherlands)

    Waveren, van I.M.; Iskandar, E.A.P.; Booi, M.; Konijnenburg-van Cittert, van J.H.A.

    2007-01-01

    A preliminary taxonomic revision of the Early Permian Jambi flora results in a lower number of taxa, a number of new determinations and several new combinations (Dicranophyllum molle (Jongmans & Gothan) comb. nov., Oligocarpia posthumii (Jongmans & Gothan) nov. comb., Callipteridium strictinervis

  15. The regeneration of a multi-ethnic mixed-use area: The case of Robin Hood Chase

    Directory of Open Access Journals (Sweden)

    Ian Bentley

    1997-01-01

    Full Text Available Urban designers show increasing interest in promoting community participation in urban regeneration and especially housing regeneration. However, effective participation has proved difficult in multi-ethnic mixed-use areas, with their wide range of different (and often conflicting interest groups. This paper, presented in case-study form, analyses a project in one such area: the Robin Hood Chase local centre in St. Ann’s area of Nottingham. It pays particular attention to the identification of different interest groups and their associated institutions, the use of local media and social events to involve these groups in the urban design process, the use of rearrangeable models in a process of “enquiry by design”, and the production of a widely acceptable urban design strategy for the area. Analysis of feedback from participants indicates a high level of satisfaction both with the final physical design proposal and with the process itself; and also identifies directions for further development in the approach and techniques employed.

  16. Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey

    Science.gov (United States)

    Wilson, John W.; Mills, Michael G. L.; Wilson, Rory P.; Peters, Gerrit; Mills, Margaret E. J.; Speakman, John R.; Durant, Sarah M.; Bennett, Nigel C.; Marks, Nikki J.; Scantlebury, Michael

    2013-01-01

    Predator–prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s−1 and accelerated up to 7.5 m s−2 with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5–8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival. PMID:24004493

  17. Cheetahs, Acinonyx jubatus, balance turn capacity with pace when chasing prey.

    Science.gov (United States)

    Wilson, John W; Mills, Michael G L; Wilson, Rory P; Peters, Gerrit; Mills, Margaret E J; Speakman, John R; Durant, Sarah M; Bennett, Nigel C; Marks, Nikki J; Scantlebury, Michael

    2013-10-23

    Predator-prey interactions are fundamental in the evolution and structure of ecological communities. Our understanding, however, of the strategies used in pursuit and evasion remains limited. Here, we report on the hunting dynamics of the world's fastest land animal, the cheetah, Acinonyx jubatus. Using miniaturized data loggers, we recorded fine-scale movement, speed and acceleration of free-ranging cheetahs to measure how hunting dynamics relate to chasing different sized prey. Cheetahs attained hunting speeds of up to 18.94 m s(-1) and accelerated up to 7.5 m s(-2) with greatest angular velocities achieved during the terminal phase of the hunt. The interplay between forward and lateral acceleration during chases showed that the total forces involved in speed changes and turning were approximately constant over time but varied with prey type. Thus, rather than a simple maximum speed chase, cheetahs first accelerate to decrease the distance to their prey, before reducing speed 5-8 s from the end of the hunt, so as to facilitate rapid turns to match prey escape tactics, varying the precise strategy according to prey species. Predator and prey thus pit a fine balance of speed against manoeuvring capability in a race for survival.

  18. Prolonged Permian–Triassic ecological crisis recorded by molluscan dominance in Late Permian offshore assemblages

    Science.gov (United States)

    Clapham, Matthew E.; Bottjer, David J.

    2007-01-01

    The end-Permian mass extinction was the largest biotic crisis in the history of animal life, eliminating as many as 95% of all species and dramatically altering the ecological structure of marine communities. Although the causes of this pronounced ecosystem shift have been widely debated, the broad consensus based on inferences from global taxonomic diversity patterns suggests that the shift from abundant brachiopods to dominant molluscs was abrupt and largely driven by the catastrophic effects of the end-Permian mass extinction. Here we analyze relative abundance counts of >33,000 fossil individuals from 24 silicified Middle and Late Permian paleocommunities, documenting a substantial ecological shift to numerical dominance by molluscs in the Late Permian, before the major taxonomic shift at the end-Permian mass extinction. This ecological change was coincident with the development of fluctuating anoxic conditions in deep marine basins, suggesting that numerical dominance by more tolerant molluscs may have been driven by variably stressful environmental conditions. Recognition of substantial ecological deterioration in the Late Permian also implies that the end-Permian extinction was the climax of a protracted environmental crisis. Although the Late Permian shift to molluscan dominance was a pronounced ecological change, quantitative counts of 847 Carboniferous–Cretaceous collections from the Paleobiology Database indicate that it was only the first stage in a stepwise transition that culminated with the final shift to molluscan dominance in the Late Jurassic. Therefore, the ecological transition from brachiopods to bivalves was more protracted and complex than their simple Permian–Triassic switch in diversity. PMID:17664426

  19. DAGMARITA SHHREZAENSIS N. SP. GLOBIVALVULINID FORAMINIFER, (WUCHIAPINGIAN, LATE PERMIAN, CENTRAL IRAN

    Directory of Open Access Journals (Sweden)

    PARVIN MOHTAT-AGHAI

    2003-03-01

    Full Text Available In the course of an investigation on the major mass extintion event near the P/T boundary, in the vicinity of Shahreza (South Isfahan in Iran, a stratigraphically significant new species of foraminifera (Dagmarita shahreaensis n. sp. has been discovered in the Wuchiapingian/Dzhulfian (Late Permian of central Iran (Hambast Formation. This new species is described and emplaced in the phylogeny of the globivalvulinid foraminifera, which evolved rapidly during the Middle/Late Permian

  20. Evidence of a therapsid scavenger in the Late Permian Karoo Basin, South Africa

    Directory of Open Access Journals (Sweden)

    Nicholas Fordyce

    2012-10-01

    Full Text Available Dicynodonts are an extinct group of herbivorous non-mammalian therapsids (‘mammal-like’ reptiles that are widely known from terrestrial Permo-Triassic strata throughout Pangaea. Dicynodont fossil remains are common within the Late Permian Beaufort Group of the Karoo Basin in South Africa. A large, partially articulated dicynodont skeleton recovered from the TropidostomaAssemblage Zone is taphonomically important in having an unusual disarticulation pattern, bone surface punctures and a broken tooth of an unidentified carnivore associated with it. Here we report on the nature of the bone damage, and the identity of the carnivore that lost a canine tooth whilst scavenging the dicynodont carcass. The morphological characteristics of the serrations on the unidentified tooth were compared with those of contemporaneous carnivores, the gorgonopsians and therocephalians. Scanning electron microscopy analysis of a silicone cast of the unidentified tooth revealed distinctive 0.5-mm square-shaped serrations. Our comparative assessment of the tooth size, curvature, cross-sectional shape and morphology of the serrations revealed that the unidentified canine most closely matched Aelurognathus,a gorgonopsian known from the same assemblage zone.

  1. The timing and pattern of biotic recovery following the end-Permian mass extinction

    Science.gov (United States)

    Chen, Zhong-Qiang; Benton, Michael J.

    2012-06-01

    The aftermath of the great end-Permian period mass extinction 252 Myr ago shows how life can recover from the loss of >90% species globally. The crisis was triggered by a number of physical environmental shocks (global warming, acid rain, ocean acidification and ocean anoxia), and some of these were repeated over the next 5-6 Myr. Ammonoids and some other groups diversified rapidly, within 1-3 Myr, but extinctions continued through the Early Triassic period. Triassic ecosystems were rebuilt stepwise from low to high trophic levels through the Early to Middle Triassic, and a stable, complex ecosystem did not re-emerge until the beginning of the Middle Triassic, 8-9 Myr after the crisis. A positive aspect of the recovery was the emergence of entirely new groups, such as marine reptiles and decapod crustaceans, as well as new tetrapods on land, including -- eventually -- dinosaurs. The stepwise recovery of life in the Triassic could have been delayed either by biotic drivers (complex multispecies interactions) or physical perturbations, or a combination of both. This is an example of the wider debate about the relative roles of intrinsic and extrinsic drivers of large-scale evolution.

  2. Palinspastic reconstruction and geological evolution of Permian residual marine basins bordering China and Mongolia

    Directory of Open Access Journals (Sweden)

    Gen-Yao Wu

    2014-04-01

    Full Text Available One main feature of the tectono-paleogeographic evolution of the southern branch of the Paleo-Asian Ocean was that there developed residual marine basins in former backarc/forearc regions after the disappearance of oceanic crust. The paper illustrates the viewpoint taking the evolution of Dalandzadgad and Solonker oceanic basins as examples. The Dalandzadgad ocean subducted southwards during the Silurian-Devonian, created an intra-oceanic arc and a backarc basin in southern Mongolia. In addition, a continent marginal arc formed along the national boundary between China and Mongolia, the south of which was a backarc basin. The oceanic basin closed and arc–arc (continent collision occurred during the early Early Permian, followed by two residual marine basins developing in the former backarc regions, named the South Gobi Basin in southern Mongolia and the Guaizihu Basin in western Inner Mongolia. The Solonker ocean subducted southwards and finally disappeared during the early Middle Permian. Afterwards, two residual marine basins occurred in northern China, the Zhesi Basin being situated in the former backarc region and the Wujiatun Basin in the former forearc region. The late Middle Permian was the most optimum period for the developing residual marine basins, when they covered a vast area. The basin evolution differentiated during the early Late Permian, with a general trend of uplift in the east and of subsidence in the west. The Upper Permian in the South Gobi Basin was characterized by coal-bearing strata hosting economically valuable coal fields. A transgression invaded westwards and the Chandmani-Bayanleg Basin was created in southwest Mongolia during the middle-late stage of the Late Permian. Correspondingly, the coal formation entered a flourishing time, with thick coal beds and sedimentary interbeds. All of these basins, namely, both the marine and nonmarine residual basins, reversed and closed by the end of Permian.

  3. Structural changes of marine communities over the Permian-Triassic transition: Ecologically assessing the end-Permian mass extinction and its aftermath

    Science.gov (United States)

    Chen, Zhong-Qiang; Tong, Jinnan; Liao, Zhuo-Ting; Chen, Jing

    2010-08-01

    The Permian/Triassic (P/Tr) transition is ecologically assessed based on examining 23 shelly communities from five shallow platform, ramp and shelf basin facies Permian-Triassic boundary (PTB) sections in South China. The shelly communities have undergone two major collapses coinciding with the two episodes of the end-Permian mass extinction. The first P/Tr extinction event devastated shelly communities in all types of settings to some extent. The basin communities have been more severely impacted than both platform and ramp communities. The survival faunas have rebounded more rapidly in shallow niches than in relatively deep habitats. The second P/Tr crisis destroyed the survival communities in shallow setting and had little impact on the basin communities in terms of community structures. The early Griesbachian communities are overall low-diversity and high-dominance. The governorship switch from brachiopods to bivalves in marine communities has been facilitated by two pulses of the end-Permian mass extinction and the whole takeover process took about 200 ka across the P/Tr boundary. Bivalve ecologic takeover initially occurred immediately after the first P/Tr extinction in shallow water habitats and was eventually completed in all niches after the second P/Tr event. Some post-extinction communities have the irregular rarefaction curves due to the unusual community structures rather than sampling intensities.

  4. A tutorial on hunting statistical significance by chasing N

    Directory of Open Access Journals (Sweden)

    Denes Szucs

    2016-09-01

    Full Text Available There is increasing concern about the replicability of studies in psychology and cognitive neuroscience. Hidden data dredging (also called p-hacking is a major contributor to this crisis because it substantially increases Type I error resulting in a much larger proportion of false positive findings than the usually expected 5%. In order to build better intuition to avoid, detect and criticise some typical problems, here I systematically illustrate the large impact of some easy to implement and so, perhaps frequent data dredging techniques on boosting false positive findings. I illustrate several forms of two special cases of data dredging. First, researchers may violate the data collection stopping rules of null hypothesis significance testing by repeatedly checking for statistical significance with various numbers of participants. Second, researchers may group participants post-hoc along potential but unplanned independent grouping variables. The first approach 'hacks' the number of participants in studies, the second approach ‘hacks’ the number of variables in the analysis. I demonstrate the high amount of false positive findings generated by these techniques with data from true null distributions. I also illustrate that it is extremely easy to introduce strong bias into data by very mild selection and re-testing. Similar, usually undocumented data dredging steps can easily lead to having 20-50%, or more false positives.

  5. Chasing behaviour and optomotor following in free-flying male blowflies: flight performance and interactions of the underlying control systems

    Directory of Open Access Journals (Sweden)

    Christine Trischler

    2010-05-01

    Full Text Available The chasing behaviour of male blowflies after small targets belongs to the most rapid and virtuosic visually guided behaviours found in nature. Since in a structured environment any turn towards a target inevitably leads to a displacement of the entire retinal image in the opposite direction, it might evoke optomotor following responses counteracting the turn. To analyse potential interactions between the control systems underlying chasing behaviour and optomotor following, respectively, we performed behavioural experiments on male blowflies and examined the characteristics of the two flight control systems in isolation and in combination. Three findings are particularly striking. (i The characteristic saccadic flight and gaze style – a distinctive feature of blowfly cruising flights – is largely abandoned when the entire visual surroundings move around the fly; in this case flies tend to follow the moving pattern in a relatively continuous and smooth way. (ii When male flies engage in following a small target, they also employ a smooth pursuit strategy. (iii Although blowflies are reluctant to fly at high background velocities, the performance and dynamical characteristics of the chasing system are not much affected when the background moves in either the same or in the opposite direction as the target. Hence, the optomotor following response is largely suppressed by the chasing system and does not much impair chasing performance.

  6. Diagenesis of Permian alluvial fan deposits of Northern Switzerland

    International Nuclear Information System (INIS)

    Bluem, W.

    1987-01-01

    Fine-grained sandstones of Permian alluvial fan deposits from three Nagra boreholes (Weiach, Riniken, Kaisten) and an exploration well, drilled at Wintersingen are clast supported, moderately sorted arkosic greywackes containing typically 2-20 % clayey matrix. Petrographic studies indicate that the origin of this clayey matrix is postdepositional. Mechanical infiltration of fines and diagenetic reddening of detrital and authigenic iron oxides are the earliest recorded events. Additionally, nodular calcites of calcrete origin and fibrous illitic clays are also ascribed to the eogenetic environment. The present strong compaction fabric results from general lack of eogenetic framework supporting cements. During mesogenesis, secondary porosity was generated through partial removal of early calcite. At the same time, a first generation of syntaxial quartz cementation and a subsequent fibrous illite authigenesis took place. Leaching of detrital K-feldspars post-dating compaction is recorded throughout the studied boreholes. The following burial diagenetic events differ between the various boreholes: in Weiach and Wintersingen kaolinite, illite, prismatic quartz and ankerite/siderite are recorded; in Riniken K-feldspar, illite, prismatic quartz and dolomite developed; whilst in Kaisten K-feldspar and microcrystalline quartz-cement dominate. These differences reflect the chemistry, pH and ionic strength of the pore fluids. Filling of veins by dolomite/ankerite, iron-rich and subsequent iron-poor calcite is the latest recorded event. (author) 21 refs., 10 figs., 1 tab

  7. Radon in the Creswell Crags Permian limestone caves

    International Nuclear Information System (INIS)

    Gillmore, G.K.; Phillips, P.S.; Denman, A.R.; Gilbertson, D.D.

    2002-01-01

    An investigation of radon levels in the caves of Creswell Crags, Derbyshire, an important Site of Special Scientific Interest (SSSI) shows that the Lower Magnesian Limestone (Permian) caves have moderate to raised radon gas levels (27-7800 Bq m -3 ) which generally increase with increasing distance into the caves from the entrance regions. This feature is partly explained in terms of cave ventilation and topography. While these levels are generally below the Action Level in the workplace (400 Bq m -3 in the UK), they are above the Action Level for domestic properties (200 Bq m -3 ). Creswell Crags has approximately 40,000 visitors per year and therefore a quantification of effective dose is important for both visitors and guides to the Robin Hood show cave. Due to short exposure times the dose received by visitors is low (0.0016 mSv/visit) and regulations concerning exposure are not contravened. Similarly, the dose received by guides is fairly low (0.4 mSv/annum) due in part to current working practice. However, the risk to researchers entering the more inaccessible areas of the cave system is higher (0.06 mSv/visit). This survey also investigated the effect of seasonal variations on recorded radon concentration. From this work summer to winter ratios of between 1.1 and 9.51 were determined for different locations within the largest cave system

  8. Electrokinetic transport behavior of phenol in upper Permian soils

    Energy Technology Data Exchange (ETDEWEB)

    Haus, R.; Zorn, R.; Czurda, K.; Ruthe, H. [Dept. of Applied Geology, Univ. Karlsruhe (Germany)

    2001-07-01

    Electrokinetic experiments with upper Permian, phenol contaminated soils ('Solaris'-area Chemnitz) were performed. Bench scale results show the successful removal of phenol. The developing soil-pH during electroremediation tests is found to affect the transport behavior of phenol strongly. If buffer solutions are used at the electrode compartments, phenol could be removed from the soils. By neutralizing the generating hydrogen ions at the anode reservoir the hydroxyl ions developing at the cathode by the electrolysis of water enter the soil and propagate to the anode by increasing the soil pH. The pH dependent dehydroxylation of phenol promotes the electromigration of negative charged phenolate ions from the cathode to the anode. At the anode the coupling of phenoxyl-radicals supports the formation of non toxic, water insoluble polyoxyphenylene by electro-polymerization. In the case of buffering the pH at the cathode uncharged phenol is transported by electroosmosis from the anode to the cathode because of the nonexisting base front and the unhindered production of hydrogen ions at the anode. (orig.)

  9. Ocean redox change at the Permian-Triassic mass extinction

    DEFF Research Database (Denmark)

    Ruhl, Micha; Bjerrum, Christian J.; Canfield, Donald Eugene

    2013-01-01

    Earth’s history is marked by multiple events of ocean anoxia developing along continental margins and po¬tentially into the open ocean realm. These events of¬ten coincide with the emplacement of large igneous provinces (LIPs) on continents, major perturbations of global geochemical cycles and mar...... these oceanographic changes to similar observations for the Triassic-Jurassic mass extinction and discuss environmental forcing, poten¬tially inherent to major volcanic events and leading to global environmental change and extinction...... ocean redox change over the largest mass extinction event in Earth history, at the Permian-Tri¬assic boundary (at ~252 Ma). This event is marked by a major perturbation in the global exogenic carbon cycle (and associated major negative carbon isotope excursion (CIE)), likely initiated by carbon...... (anoxic but not euxinic) coinciding with the main extinction event. Molybdenum enrichments, often indicative for freely available sulfide in the water-column, only occur dur¬ing the second phase of euxinia. This pattern of ocean redox-change in Svalbard direct¬ly reflects similar trends in Greenland...

  10. Simulated warm polar currents during the middle Permian

    Energy Technology Data Exchange (ETDEWEB)

    Winguth, A M.E.; Kutzbach, J E [Wisconsin Univ., Madison, WI (USA). Center for Climatic Research; Heinze, C; Maier-Reimer, E; Mikolajewicz, U [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Rowley, D; Rees, A; Ziegler, A M [Chicago Univ., IL (United States). Dept. of Geophysical Sciences

    2001-05-01

    During Permian Stage 6 (Wordian, Kazanian) the Pangaean supercontinent was surrounded by a superocean - Panthalassa. An ocean general circulation model has been coupled to an atmospheric energy balance model to simulate the sensitivity of the Wordian climate ({proportional_to}265 million years ago) to changes in greenhouse gas concentrations, high latitude geography, and Earth orbital configurations. The model shows a high sensitivity of the ocean circulation to changes in the greenhouse gas forcing, ranging from a forceful southern circulation at low CO{sub 2} concentration (present level) to a more symmetric circulation cell with deep water formation in both hemispheres at high CO{sub 2} concentration (8 x present level). The simulated climate with 4 x present level CO{sub 2} concentration agrees generally well with climate-sensitive sediments and phytogeographic patterns. In this experiment, the model simulates strong subtropical gyres with similarities to the modern South Pacific circulation and moderate surface temperatures on the southern continent Gondwana, resulting from a strong poleward heat transport in the ocean. An even more moderate climate can be generated if high latitude land is removed so that ocean currents can penetrate into the polar regions or if orbital configurations favor high summer insolation over Gondwana. (orig.)

  11. The Permian reptile Opisthodontosaurus carrolli: a model for acrodont tooth replacement and dental ontogeny.

    Science.gov (United States)

    Haridy, Yara; LeBlanc, Aaron R H; Reisz, Robert R

    2018-03-01

    Continuous tooth replacement is common for tetrapods, but some groups of acrodont lepidosaurs have lost the ability to replace their dentition (monophyodonty). Acrodonty, where the tooth attaches to the apex of the jawbone, is an unusual form of tooth attachment that has been associated with the highly autapomorphic condition of monophyodonty. Beyond Lepidosauria, very little is known about the relationship between acrodonty and monophyodonty in other amniotes. We test for this association with a detailed study of the dentition of Opisthodontosaurus, an unusual Early Permian captorhinid eureptile with acrodont dentition. We provide clear evidence, both histological and morphological, that there were regular tooth replacement events in the lower jaw of Opisthodontosaurus, similar to its captorhinid relatives. Thus, our study of the oldest known amniote with an acrodont dentition shows that acrodonty does not inhibit tooth replacement, and that many of the characteristics assigned to lepidosaurian acrodonty are actually highly derived features of lepidosaurs that have resulted secondarily from a lack of tooth replacement. In the context of reptilian dental evolution, we propose the retention of the simple definition of acrodonty, which only pertains to the relative position of the tooth at the apex of the jaw, where the jaw possesses equal lingual and labial walls. This definition of implantation therefore focuses solely on the spatial relationship between the tooth and the jawbone, and separates this relationship from tooth development and replacement. © 2017 Anatomical Society.

  12. Revised stratigraphy of the Permian Bainmedart coal measures, northern Prince Charles Mountains, east Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    McLoughlin, S.; Drinnan, A.N. [University of Melbourne, Parkville, Vic. (Australia). School of Botany

    1997-05-01

    The Bainmedart Coal Measures constitute the middle portion of the Permian-Triassic Amery Group, which represents the only substantial Palaeozoic-Mesozoic sedimentary succession exposed in eastern Antarctica outside the Transantarctic Mountains. The coal measures overlie alluvial fan deposits of the Radok Conglomerate and are conformably overlain by the dominantly fluviatile Flagstone Bench Formation. The coal measures were deposited within alluvial settings dominated by north to northeasterly flowing, low-sinuosity rivers chiefly confined to broad, fault-bounded, valleys of the Lambert Graben, a major late Palaeozoic to early Mesozoic failed rift system. Both climatic and local tectonic factors are considered to have been the major influences on the pattern of coal measure sedimentation. Recent mapping has identified a much greater thickness of sediments within the coal measures than had been inferred previously. The Bainmedart Coal Measures are formally subdivided into six members. In ascending stratigraphic order these are: Dart Fields Conglomerate Member ({lt} 3m thick), Toploje Member (300 m thick), Dragons Teeth Member (15-25 m thick), Glossopteris Gully Member (670 m thick), Grainer Member (350 m thick), acid McKinnon Member (530 m thick).

  13. Pilots' Attention Distributions Between Chasing a Moving Target and a Stationary Target.

    Science.gov (United States)

    Li, Wen-Chin; Yu, Chung-San; Braithwaite, Graham; Greaves, Matthew

    2016-12-01

    Attention plays a central role in cognitive processing; ineffective attention may induce accidents in flight operations. The objective of the current research was to examine military pilots' attention distributions between chasing a moving target and a stationary target. In the current research, 37 mission-ready F-16 pilots participated. Subjects' eye movements were collected by a portable head-mounted eye-tracker during tactical training in a flight simulator. The scenarios of chasing a moving target (air-to-air) and a stationary target (air-to-surface) consist of three operational phases: searching, aiming, and lock-on to the targets. The findings demonstrated significant differences in pilots' percentage of fixation during the searching phase between air-to-air (M = 37.57, SD = 5.72) and air-to-surface (M = 33.54, SD = 4.68). Fixation duration can indicate pilots' sustained attention to the trajectory of a dynamic target during air combat maneuvers. Aiming at the stationary target resulted in larger pupil size (M = 27,105, SD = 6565), reflecting higher cognitive loading than aiming at the dynamic target (M = 23,864, SD = 8762). Pilots' visual behavior is not only closely related to attention distribution, but also significantly associated with task characteristics. Military pilots demonstrated various visual scan patterns for searching and aiming at different types of targets based on the research settings of a flight simulator. The findings will facilitate system designers' understanding of military pilots' cognitive processes during tactical operations. They will assist human-centered interface design to improve pilots' situational awareness. The application of an eye-tracking device integrated with a flight simulator is a feasible and cost-effective intervention to improve the efficiency and safety of tactical training.Li W-C, Yu C-S, Braithwaite G, Greaves M. Pilots' attention distributions between chasing a moving target and a stationary target. Aerosp Med

  14. A new type of coating to chase the clouds away

    CERN Multimedia

    Stefania Pandolfi

    2016-01-01

    The electron cloud problem needs to be addressed with innovative solutions, particularly in view of the rapidly approaching HL-LHC upgrade. CERN’s Vacuum, Surfaces and Coatings group has greatly improved its amorphous carbon coating technique, which is an alternative to the scrubbing process used so far. This technique is now fully mature and is being used for the vacuum chambers of the SPS magnets and the delicate beam screens of the LHC’s quadrupole triplets.   The violet light is produced by the argon plasma used when sputtering the amorphous carbon. The beam screen is coated in this case using the magnetic field of the quadrupole itself. (Image: Pedro Costa Pinto) We know that conditioning (or “scrubbing”) the beam pipe reduces the avalanche-like creation of secondary electrons from the tube’s walls, thus preventing the formation of unwanted electron clouds. But it has also been observed that scrubbing natur...

  15. International Conference on Metalorganic Vapor Chase Epitaxy (ICMOVPE) XVIII

    Energy Technology Data Exchange (ETDEWEB)

    Dupuis, Russell D. [Georgia Inst. of Technology, Atlanta, GA (United States)

    2017-05-05

    The ICMOVPE-XVIII conference created meaningful opportunities for intellectual challenge, networking opportunities, and intellectual stimulation for graduate students, Post-Doctoral Fellows and all attendees. This technical and social program further provided many opportunities for communication, brainstorming, and transfer of information as well as the development of collaborations across many institutions and companies. We had a significant number of members of underrepresented groups in STEM attending this conference. We also are publishing the proceedings of this conference with the Journal of Crystal Growth, a journal which receives wide electronic distribution in many academic institutions world-wide, making the technical information presented at ICMOVPE-XVIII have a much broader impact than would otherwise be possible. ICMOVPE XVIII had a total of 216 presentations and of these; there were 70 Student oral or poster presentations. The funds we obtained for student support from the Department of Energy were distributed among the registered students and Post Docs to supplement the full cost of registration of $1,100 each for regular registration to the reduced rate of at $850 each for graduate students and Post Docs.

  16. Bioessential element-depleted ocean following the euxinic maximum of the end-Permian mass extinction

    Science.gov (United States)

    Takahashi, Satoshi; Yamasaki, Shin-ichi; Ogawa, Yasumasa; Kimura, Kazuhiko; Kaiho, Kunio; Yoshida, Takeyoshi; Tsuchiya, Noriyoshi

    2014-05-01

    We describe variations in trace element compositions that occurred on the deep seafloor of palaeo-superocean Panthalassa during the end-Permian mass extinction based on samples of sedimentary rock from one of the most continuous Permian-Triassic boundary sections of the pelagic deep sea exposed in north-eastern Japan. Our measurements revealed low manganese (Mn) enrichment factor (normalised by the composition of the average upper continental crust) and high cerium anomaly values throughout the section, suggesting that a reducing condition already existed in the depositional environment in the Changhsingian (Late Permian). Other redox-sensitive trace-element (vanadium [V], chromium [Cr], molybdenum [Mo], and uranium [U]) enrichment factors provide a detailed redox history ranging from the upper Permian to the end of the Permian. A single V increase (representing the first reduction state of a two-step V reduction process) detected in uppermost Changhsingian chert beds suggests development into a mildly reducing deep-sea condition less than 1 million years before the end-Permian mass extinction. Subsequently, a more reducing condition, inferred from increases in Cr, V, and Mo, developed in overlying Changhsingian grey siliceous claystone beds. The most reducing sulphidic condition is recognised by the highest peaks of Mo and V (second reduction state) in the uppermost siliceous claystone and overlying lowermost black claystone beds, in accordance with the end-Permian mass extinction event. This significant increase in Mo in the upper Changhsingian led to a high Mo/U ratio, much larger than that of modern sulphidic ocean regions. This trend suggests that sulphidic water conditions developed both at the sediment-water interface and in the water column. Above the end-Permian mass extinction horizon, Mo, V and Cr decrease significantly. On this trend, we provide an interpretation of drawdown of these elements in seawater after the massive element precipitation event

  17. Permian and Triassic microfloral assemblages from the Blue Nile Basin, central Ethiopia

    Science.gov (United States)

    Dawit, Enkurie L.

    2014-11-01

    Palynological investigation was carried out on surface samples from up to 400 m thick continental siliciclastic sediments, here referred to as “Fincha Sandstone”, in the Blue Nile Basin, central Ethiopia. One hundred sixty species were identified from 15 productive samples collected along a continuous road-cut exposure. Six informal palynological assemblage zones have been identified. These assemblage zones, in ascending order, are: “Central Ethiopian Permian Assemblage Zone - CEPAZ I”, earliest Permian (Asselian-Sakmarian); “CEPAZ II”, late Early Permian (Artinskian-Kungurian); CEPAZ III - Late Permian (Kazanian-Tatarian); “CETAZ IV”, Lower Triassic (Olenekian Induan); “CETAZ V”, Middle Triassic (Anisian Ladinian); “CETAZ VI”, Late Triassic (Carnian Norian). Tentative age ranges proposed herein are compared with faunally calibrated palynological zones in Gondwana. The overall composition and vertical distribution of miospores throughout the studied section reveals a wide variation both qualitatively and quantitatively. The high frequency of monosaccate pollen in CEPAZ I may reflect a Glossopterid-dominated upland flora in the earliest Permian. The succeeding zone is dominated by straite/taeniate disaccate pollen and polyplicates, suggesting a notable increase in diversity of glossopterids. The decline in the diversity of taeniate disaccate pollen and the concomitant rise in abundance of non-taeniate disaccates in CEPAZ III may suggest the decline in Glossopteris diversity, though no additional evidence is available to equate this change with End-Permian extinction. More diverse and dominant non-taeniate, disaccate, seed fern pollen assignable to FalcisporitesAlisporites in CETAZ IV may represent an earliest Triassic recovery flora. The introduction of new disaccate forms with thick, rigid sacci, such as Staurosaccites and Cuneatisporites, in CETAZ V and VI may indicate the emergence of new gymnospermous plants that might have favourably

  18. The neutron therapy facility at the University of Pennsylvania-Fox Chase Cancer Center

    International Nuclear Information System (INIS)

    Bloch, P.; Chu, J.; Larsen, R.

    1983-01-01

    The fusion of deuterium and tritium nuclei results in the formation of a helium-4 nucleus and a 14 MEV neutron. This reaction readily takes place when deuterium and tritium ions are accelerated to potentials between 150-200 kV. These energy ions can be obtained in a moderate size accelerator. A DT neutron facility has been installed in the radiation therapy department of the University of Pennsylvania Hospital-Fox Chase Cancer Center. The system is being commissioned in a hospital setting to test the efficacy of fast neutron radiotherapy

  19. 40Ar/ 39Ar dating of Late Permian evaporites, southeastern New Mexico, USA

    Science.gov (United States)

    Renne, Paul R.; Sharp, Warren D.; Montañez, Isabel P.; Becker, Tim A.; Zierenberg, Robert A.

    2001-12-01

    40Ar/ 39Ar dating of the potassium-magnesium sulfate mineral langbeinite from Permian evaporites of the Salado formation near Carlsbad, New Mexico, provides quantitative evidence that some salts in these deposits have not recrystallized for 251 Myr since deposition. Survival of Permian salts supports the possibility that Bacillus bacteria recovered from nearby halite was isolated in a closed system and represents a sample of uncontaminated Permian life. Local recrystallization of langbeinite and other nearby minerals is also indicated by the dating, suggesting both the need and the opportunity to document closed system behavior more rigorously. The shoaling and desiccation event recorded by the Salado formation began at least 1 Myr before the Permian-Triassic boundary. Temporal correlation of the Salado with the Zechstein evaporites of north-central Europe supports previously inferred regression models for the origin of these deposits. Significant paleoenvironmental change at the Permian-Triassic boundary thus occurred on a time scale more protracted than that implied by geologically instantaneous events such as bolide impacts.

  20. Geochemical characteristics of Carboniferous-Permian coal-formed gas in Bohai Bay Basin

    Energy Technology Data Exchange (ETDEWEB)

    Shipeng Huang; Fengrong Liao; Xiaoqi Wu [PetroChina, Beijing (China). Research Institute of Petroleum Exploration & Development

    2010-03-15

    Coal-formed gas reservoirs have been found in several depressions in Bohai Bay Basin. The gas was mainly generated by the Carboniferous-Permian coal measures, which are good source rocks. The exploration of coal-formed gas has a broad prospect. The main reservoirs of the coal-formed gas are Ordovician, Carboniferous-Permian, and Paleogene stratum. Coal-formed gas in the Bohai Bay Basin is chiefly composed of hydrocarbon gases. The percentage content of carbon dioxide is more than that of the nitrogen gas. The stable carbon isotope values of the hydrocarbon gases of different depressions and different reservoirs usually reversed. The reversed values of gas samples account for 52.1% of all the samples. Reversion values of the carbon isotope are mainly because of the mixing of gases from same source rocks but with different maturity. Among the three main reservoirs, coal-formed gas preserved in Paleogene stratum has the heaviest carbon isotope, the second is the gas in Carboniferous-Permian stratum, and the Ordovician gas possesses the lightest carbon isotope. Based on the analysis of the characteristics of carbon isotope of hydrocarbon gases in well Qishen-1 and the distribution of the Carboniferous-Permian coal measures, the gas of the well is derived from the high-matured Carboniferous-Permian coal measures.

  1. Vaping on Instagram: cloud chasing, hand checks and product placement.

    Science.gov (United States)

    Chu, Kar-Hai; Allem, Jon-Patrick; Cruz, Tess Boley; Unger, Jennifer B

    2016-09-01

    This study documented images posted on Instagram of electronic cigarettes (e-cigarette) and vaping (activity associated with e-cigarette use). Although e-cigarettes have been studied on Twitter, few studies have focused on Instagram, despite having 500 million users. Instagram's emphasis on images warranted investigation of e-cigarettes, as past tobacco industry strategies demonstrated that images could be used to mislead in advertisements, or normalise tobacco-related behaviours. Findings should prove informative to tobacco control policies in the future. 3 months of publicly available data were collected from Instagram, including images and associated metadata (n=2208). Themes of images were classified as (1) activity , for example, a person blowing vapour; (2) product , for example, a personal photo of an e-cigarette device; (3) advertisement ; (4) text , for example, 'meme' or image containing mostly text and (5) other . User endorsement (likes) of each type of image was recorded. Caption text was analysed to explore different trends in vaping and e-cigarette-related text. Analyses found that advertisement -themed images were most common (29%), followed by product (28%), and activity (18%). Likes were more likely to accompany activity and product -themed images compared with advertisement or text -themed images (pInstagram affords its users the ability to post images of e-cigarette-related behaviours and gives advertisers the opportunity to display their product. Future research should incorporate novel data streams to improve public health surveillance, survey development and educational campaigns. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. Paratingia wudensis sp. nov., a whole noeggerathialean plant preserved in an earliest Permian air fall tuff in Inner Mongolia, China

    Czech Academy of Sciences Publication Activity Database

    Wang, J.; Pfefferkorn, H. W.; Bek, Jiří

    2009-01-01

    Roč. 96, č. 9 (2009), s. 1676-1689 ISSN 0002-9122 R&D Projects: GA AV ČR IAA301110701 Institutional research plan: CEZ:AV0Z30130516 Keywords : noeggerathiales * whole plant reconstruction * in situ spores * Permian * Permian (China) Subject RIV: EF - Botanics Impact factor: 2.684, year: 2009

  3. 78 FR 16569 - Iowa Pacific Holdings, LLC, Permian Basin Railways, and San Luis & Rio Grande Railroad-Corporate...

    Science.gov (United States)

    2013-03-15

    ... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35721] Iowa Pacific Holdings, LLC, Permian Basin Railways, and San Luis & Rio Grande Railroad--Corporate Family Transaction... subsidiaries Permian Basin Railways (PBR) and San Luis & Rio Grande Railroad (SLRG), and Massachusetts Coastal...

  4. Architecture and evolution of an Early Permian carbonate complex on a tectonically active island in east-central California

    Science.gov (United States)

    Stevens, Calvin H.; Magginetti, Robert T.; Stone, Paul

    2015-01-01

    The newly named Upland Valley Limestone represents a carbonate complex that developed on and adjacent to a tectonically active island in east-central California during a brief interval of Early Permian (late Artinskian) time. This lithologically unique, relatively thin limestone unit lies within a thick sequence of predominantly siliciclastic rocks and is characterized by its high concentration of crinoidal debris, pronounced lateral changes in thickness and lithofacies, and a largely endemic fusulinid fauna. Most outcrops represent a carbonate platform and debris derived from it and shed downslope, but another group of outcrops represents one or possibly more isolated carbonate buildups that developed offshore from the platform. Tectonic activity in the area occurred before, probably during, and after deposition of this short-lived carbonate complex.

  5. Ocean anoxia did not cause the Latest Permian Extinction

    Science.gov (United States)

    Proemse, Bernadette C.; Grasby, Stephen E.; Wieser, Michael E.; Mayer, Bernhard; Beauchamp, Benoit

    2014-05-01

    The Latest Permian Extinction (LPE, ~252 million years ago) was a turning point in the history of life on Earth with a loss of ~96% of all marine species and ~70% of all terrestrial species. While, the event undoubtedly shaped the evolution of life its cause remains enigmatic. A leading hypothesis is that the global oceans became depleted in oxygen (anoxia). In order to test this hypothesis we investigated a proxy for marine oxygen levels (molybdenum isotopic composition) in shale across the LPE horizon located on the subtropical northwest margin of Pangea at that time. We studied two sedimentary records in the Sverdrup basin, Canadian High Arctic: Buchanan Lake (eastern Axel Heiberg Island; 79° 26.1'N, 87° 12.6'W), representing a distal deep-water slope environment, and West Blind Fiord (southwest Ellesmere Island; 78° 23.9'N, 85° 57.2'W), representing a deep outer shelf environment (below storm wave base). The molybdenum isotopic composition (δ98/95Mo) of sediments has recently become a powerful tool as a paleo-oceanographic proxy of marine oxygen levels. Sample preparation was carried out in a metal-free clean room facility in the isotope laboratory of the Department of Physics and Astronomy, University of Calgary, Canada, that is supplied by HEPA-filtered air. Molybdenum isotope ratios were determined on a Thermo Scientific multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) with an uncertainty better than ±0.10o for δ98/95Mo values. Results from the Buchanan Lake section show a large shift in δ98/95Mo values from 2.02o to +2.23o at the extinction horizon, consistent with onset of euxinic conditions. In contrast, West Blind Fiord shales, representing the sub-storm wave base shelf environment, show little change in the molybdenum isotopic composition (1.34o to +0.05), indicating ongoing oxic conditions across the LPE (Proemse et al., 2013). Our results suggest that areas of the Pangea continental shelf (North West Pangea) experienced

  6. Permian tetrapods from the Sahara show climate-controlled endemism in Pangaea.

    Science.gov (United States)

    Sidor, Christian A; O'Keefe, F Robin; Damiani, Ross; Steyer, J Sébastien; Smith, Roger M H; Larsson, Hans C E; Sereno, Paul C; Ide, Oumarou; Maga, Abdoulaye

    2005-04-14

    New fossils from the Upper Permian Moradi Formation of northern Niger provide an insight into the faunas that inhabited low-latitude, xeric environments near the end of the Palaeozoic era (approximately 251 million years ago). We describe here two new temnospondyl amphibians, the cochleosaurid Nigerpeton ricqlesi gen. et sp. nov. and the stem edopoid Saharastega moradiensis gen. et sp. nov., as relicts of Carboniferous lineages that diverged 40-90 million years earlier. Coupled with a scarcity of therapsids, the new finds suggest that faunas from the poorly sampled xeric belt that straddled the Equator during the Permian period differed markedly from well-sampled faunas that dominated tropical-to-temperate zones to the north and south. Our results show that long-standing theories of Late Permian faunal homogeneity are probably oversimplified as the result of uneven latitudinal sampling.

  7. Archaeolithoporella and Tubiphytes : Affinties and Paleoecology in Permian Reefs of South China

    Institute of Scientific and Technical Information of China (English)

    王生海; 范嘉松; J.Keith Rigby

    1994-01-01

    Archaeolithoporella is one of the most important Permian reef-building organisms, but itsaffinity has long been controversial. It was first reported in Japan and was considered as a coralline red alga. Since then it has been recognized in Permian reefs in other parts of the world. Many researchers have studied the materials they had found and the Japanese holotype specimen. Most have concluded that it is a problematic alga. or just a problematica because of weak criteria for definition. Some have even considered it inorganic. However, relict cellular structures and microtubular laminae found in well-preserved specimens from Permian reefs in South China strongly support a coralline red algal affinity for the genus.In situ preserved Archaeolithoporella is restricted within the typical framework facies and it occurs most abundantly in syndepositionally cemented framestones. This suggests that Archaeolithoporella required a firm substrate and clear but agitated sea water. Archaeolithoporella is often found

  8. Trouble Upstairs: Reconstructing Permian-Triassic Climate during Siberian Traps Magmatism

    Science.gov (United States)

    Black, B. A.; Neely, R. R., III; Lamarque, J. F.; Elkins-Tanton, L. T.; Mills, M. J.

    2014-12-01

    The eruption of large igneous provinces can transfer significant masses of volatiles from Earth's interior to the atmosphere. What are the consequences of this degassing for habitability and extinction? In this presentation, we consider this question in the context of Siberian Traps magmatism, which has been shown to overlap within geochronologic uncertainty with catastrophic deterioration of Permian-Triassic marine and terrestrial ecosystems. To investigate the impacts of endogenic gases on climate, atmospheric chemistry, and ocean circulation, we conducted a series of numerical experiments with a comprehensive global model for the Permian-Triassic. Our simulations predict the intensity and distribution of acid rain and ozone depletion, with implications for terrestrial biota. We further explore feedbacks between sulfur emissions, transient cooling, and shifts in ocean circulation. We suggest that Siberian Traps magmatism may have triggered several distinct kill mechanisms in the oceans and on land, contributing to a complex combined pattern of environmental stress and latest Permian ecological failure.

  9. Origin of the Permian-Triassic komatiites, northwestern Vietnam

    Science.gov (United States)

    Hanski, Eero; Walker, Richard J.; Huhma, Hannu; Polyakov, Gleb V.; Balykin, Pavel A.; Tran Trong Hoa; Ngo Thi Phuong

    Rare examples of Phanerozoic komatiites are found in the Song Da zone, NW Vietnam. These komatiites were erupted through continental crust and may belong to the SE extension of the Permo-Triassic Emeishan volcanic province located in SW China. They provide a good opportunity to study the source characteristics of starting plume magmas in a continental flood basalt province. Erupted on late-Permian carbonate rocks, the komatiitic rocks are interbedded with low-Ti olivine basalts. Basaltic komatiites display pyroxene spinifex textures, while more magnesian rocks (MgO up to 32 wt.%) are porphyritic, containing a single, cognate population of euhedral to elongated olivine phenocrysts with Fo up to 93.0%. This suggests a highly magnesian parental magma with 22-23 wt.% MgO. In terms of major and minor elements, the komatiites are similar to the ca. 89 Ma old Gorgona Island komatiites of Colombia. The Song Da komatiites are also strongly light-rare-earth-element- (LREE) depleted (CeN/YbN 0.30-0.62) and have unfractionated heavy rare earth element (HREE) patterns. The komatiites have high Os concentrations (up to 7.0 ppb), low but variable Re/Os ratios, and define an isochron with an age of 270+/-21 Ma, and an initial 188Os/187Os ratio of 0.12506+/- 0.00041 (γOs=+0.02+/-0.40). The Os isotopic systematics of the komatiites show no effects of crustal contamination. In contrast, their initial ɛNd values range from +3 to +8, reflecting varying but generally small degrees of contamination with Proterozoic sialic basement material. Associated low-Ti basalts have low initial ɛNd values (-0.8 to -7.5), high initial γOs values (>=15), flat or LREE-enriched REE patterns, and Nb-Ta depletion. These characteristics are also attributed to variable extents of crustal contamination.

  10. Anatomically preserved "strobili" and leaves from the Permian of China (Dorsalistachyaceae, fam. nov.) broaden knowledge of Noeggerathiales and constrain their possible taxonomic affinities.

    Science.gov (United States)

    Wang, Shi-Jun; Bateman, Richard M; Spencer, Alan R T; Wang, Jun; Shao, Longyi; Hilton, Jason

    2017-01-01

    Noeggerathiales are an extinct group of heterosporous shrubs and trees that were widespread and diverse during the Pennsylvanian-Permian Epochs (323-252 Ma) but are of controversial taxonomic affinity. Groups proposed as close relatives include leptosporangiate ferns, sphenopsids, progymnosperms, or the extant eusporangiate fern Tmesipteris. Previously identified noeggerathialeans lacked anatomical preservation, limiting taxonomic comparisons to their external morphology and spore structure. We here document from the upper Permian of China the first anatomically preserved noeggerathialeans, which enhance the perceived distinctiveness of the group and better indicate its systematic affinity. We describe in detail the newly discovered, anatomically preserved heterosporous strobilus Dorsalistachya quadrisegmentorum, gen. et sp. nov., and redescribe its suspected foliar correlate, the pinnate leaf Plagiozamites oblongifolius. Plagiozamites possesses an omega (Ω)-shaped vascular trace and prominent cortical secretory cavities-a distinctive anatomical organization that is echoed in the newly discovered strobili. Dorsalistachya strobili bear highly dissected sporophylls alternately in two vertical rows, suggesting that they are homologs of leaf pinnae. If so, the "strobilus" is strictly a pseudostrobilus and consists of sporangium-bearing units that are one hierarchical level below true sporophylls. The "sporophylls" bear four microsporangia on the lower (abaxial) surface, occasionally interspersed with short longitudinal rows of megasporangia. A single functional megaspore develops within each winged megasporangium, suggesting adaptation for dispersal as a single unit. Dorsalistachya presents a unique combination of reproductive features that amply justifies establishment of a new family, Dorsalistachyaceae. Noeggerathiales represent a distinct taxonomic Order of free-sporing plants that most resembles early-divergent eusporangiate ferns and the more derived among the

  11. Sedimentary features and exploration targets of Middle Permian reservoirs in the SW Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guoming Xu

    2015-11-01

    Full Text Available The exploration direction and targets for the large-scale Middle Permian gas reservoirs in the Sichuan Basin are hot spots and challenges in current exploration researches. The exploration successes of large gas field of Cambrian Longwangmiao Formation in Gaoshiti-Moxi region, Central Sichuan Basin, indicated that prospective sedimentary facies belt was the basis for the formation of large gas fields. In this paper, based on seismic data, outcrop data and drilling data, the tectonic framework and sedimentary features of the Middle Permian in the SW Sichuan Basin were comprehensively studied. The following conclusions were reached from the perspective of sedimentary facies control: (1 during the Middle Permian, this region was in shallow water gentle slope belts with high energy, where thick reef flat facies were deposited; (2 the basement was uplifted during Middle Permian, resulting in the unconformity weathering crust at the top of Maokou Formation due to erosion; the SW Sichuan Basin was located in the karst slope belt, where epigenic karstification was intense; and (3 reef flat deposits superimposed by karst weathering crust was favorable for the formation of large-scale reef flat karst reservoirs. Based on the combination of the resources conditions and hydrocarbon accumulation conditions in this region, it was pointed out that the Middle Permian has great potential of large-scale reef flat karst gas reservoir due to its advantageous geological conditions; the Middle Permian traps with good hydrocarbon accumulation conditions were developed in the Longmen Mountain front closed structural belt in the SW Sichuan Basin and Western Sichuan Basin depression slope belt, which are favorable targets for large-scale reef flat karst reservoirs.

  12. Upper Permian ostracode assemblage from the Jadar Block (Vardar zone, NW Serbia

    Directory of Open Access Journals (Sweden)

    Crasquin Sylvie

    2010-01-01

    Full Text Available Ostracodes from the Changhsingian (latest Permian age in the uppermost part of the “Bituminous Limestone” Formation of the Komirić Section in NW Serbia (Jadar Block, Vardar Zone are described and illustrated. Three new species of ostracodes are introduced: Basslerella jadarensis n. sp., Acratia serbianella n. sp., and Knoxiella vardarensis n. sp. The ostracode assemblage, together with conodonts and foraminifers, is the first record of the youngest Late Permian age microfaunas from Serbia and from the central part of the Balkan Peninsula.

  13. CHASE '10

    DEFF Research Database (Denmark)

    Software is created by people---software engineers---working in varied environments, under various conditions. Thus understanding cooperative and human aspect of software development is crucial to comprehend how methods and tools are used, and thereby improving the creation and maintenance of sof...

  14. Chasing volatility

    DEFF Research Database (Denmark)

    Caporin, Massimiliano; Rossi, Eduardo; Santucci de Magistris, Paolo

    The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification, the condi......The realized volatility of financial returns is characterized by persistence and occurrence of unpreditable large increments. To capture those features, we introduce the Multiplicative Error Model with jumps (MEM-J). When a jump component is included in the multiplicative specification...... estimate alternative specifications of the model using a set of daily bipower measures for 7 stock indexes and 16 individual NYSE stocks. The estimates of the jump component confirm that the probability of jumps dramatically increases during the financial crisis. Compared to other realized volatility...... models, the introduction of the jump component provides a sensible improvement in the fit, as well as for in-sample and out-of-sample volatility tail forecasts....

  15. An appraisal of the Permian palaeobiodiversity and geology of the Ib-River Basin, eastern coastal area, India

    Science.gov (United States)

    Goswami, Shreerup; Saxena, Anju; Singh, Kamal Jeet; Chandra, Shaila; Cleal, Christopher J.

    2018-05-01

    The Ib-River Basin situated in the east coastal area of India, in Odisha State is a south-eastern part of the Mahanadi Master Basin. A large number of plant macrofossils belonging to the Glossopteris flora were described and documented between 2006 and 2010 from various localities of the Barakar and Lower Kamthi formations of this basin. The floral components representing leaves, roots and fructifications in these assemblages belong to the Lycopodiales, Equisetales, Sphenophyllales, Filicales, Cordaitales, Cycadales, Ginkgoales, Coniferales and Glossopteridales. In the present study, all the available data pertaining to the biological remains, petrological analyses as well as the geology of this basin are reviewed and analyzed to deduce and reconstruct the biostratigraphy, palaeoclimate, palaeoenvironment and the landscape of this basin during Permian time in general and during the deposition of Barakar (Artinskian - Kungurian) and Lower Kamthi (Lopingian) formations in particular. The floral composition suggests the prevalence of a temperate climate with a slight change from warm moist to warm dry conditions during the deposition of the Barakar Formation and warm and humid during the deposition of Lower Kamthi sediments. Distribution of various plant groups in the Barakar and Lower Kamthi formations have been shown to depict the biodiversity trends. Vegetational reconstructions during the deposition of the Barakar and Lower Kamthi formations around the Ib-River Basin have also been attempted based on all the fossil records from this area. The status of unclassified Barakar and Kamthi formations has been redefined. Apart from megafloristics, the palynology of the basin is also discussed. Possible marine incursions and marine marginal environment in the Ib-Basin during Permian are overtly summarized on the basis of records of acritarchs, typical marine ichnofossils and evidences of wave activity in Lower Gondwana sediments of this Basin.

  16. Origin of Permian OIB-like basalts in NW Thailand and implication on the Paleotethyan Ocean

    Science.gov (United States)

    Wang, Yuejun; He, Huiying; Zhang, Yuzhi; Srithai, Boontarika; Feng, Qinglai; Cawood, Peter A.; Fan, Weiming

    2017-03-01

    The basaltic rocks in NW Thailand belong to part of giant Southeast Asian igneous zone that delineates the extension of the Paleotethyan Ocean from SW China into NW Thailand. The Chiang Mai basaltic samples from the Chiang Dao, Fang, Lamphun and Ban Sahakorn sections are divisible into two groups of high-iron basalt. Group 1 has SiO2 of 38.30-49.18 wt.%, FeOt of 13.09-25.37 wt.%, MgO of 8.38-1.60 wt.%, TiO2 of 3.92-6.30 wt.%, which is rarely observed in nature. Group 2 shows SiO2 = 44.71-49.21 wt.%, FeOt = 10.88-14.34 wt.%, MgO = 5.24-16.11 wt.%, TiO2 = 2.22-3.07 wt.% and mg# = 44-70. Olivine and pyroxene are responsible for the fractionation of the Group 2 magma whereas low oxygen fugacity during the late-stage differentiation of the Group 1 magma prolonged fractionation of ilmenite and magnetite. The onset of ilmenite and magnetite fractionations controls the distinct differentiation commencing at MgO = 7 wt.%. Both groups show similar REE and primitive mantle-normalized patterns with insignificant Eu, Nb-Ta and Zr-Hf anomalies. They have similar Nd isotopic compositions with εNd (t) values ranging from + 2.8 to + 3.7 and similar Nb/La, Nb/U, Th/La, Zr/Nb, Th/Ta, La/Yb, Nb/Th, Nb/Y and Zr/Y, resembling those of OIB-like rocks. The representative basaltic sample yields the argon plateau age of 282.3 ± 1.4 Ma, suggestive of Early Permian origin. Our data argue for Group 1 and Group 2 are coeval in the intra-oceanic seamount setting within the Paleotethyan Ocean, which at least continued till 283 Ma. These data, along with other observations, suggest that the Inthanon zone defines the main Paleotethyan suture zone, which northerly links with the Changning-Menglian suture zone in SW China.

  17. 76 FR 31955 - Jonathan and Jayne Chase; Notice of Application Accepted for Filing With the Commission, Intent...

    Science.gov (United States)

    2011-06-02

    .... c. Date filed: July 23, 2010. d. Applicant: Jonathan and Jayne Chase. e. Name of Project: Troy Hydropower Project. f. Location: On the Missisquoi River, in the Town of Troy, Orleans County, Vermont. The... filing and is now ready for environmental analysis. l. Project Description: The Troy Project would...

  18. Biosynthesis of intestinal microvillar proteins. Pulse-chase labelling studies on maltase-glucoamylase, aminopeptidase A and dipeptidyl peptidase IV

    DEFF Research Database (Denmark)

    Danielsen, E M; Sjöström, H; Norén, Ove

    1983-01-01

    The biogenesis of three intestinal microvillar enzymes, maltase-glucoamylase (EC 3.2.1.20), aminopeptidase A (aspartate aminopeptidase, EC 3.4.11.7) and dipeptidyl peptidase IV (EC 3.4.14.5), was studied by pulse-chase labelling of pig small-intestinal explants kept in organ culture. The earliest...

  19. Turnover rates in microorganisms by laser ablation electrospray ionization mass spectrometry and pulse-chase analysis

    Energy Technology Data Exchange (ETDEWEB)

    Stopka, Sylwia A.; Mansour, Tarek R.; Shrestha, Bindesh [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States); Maréchal, Éric; Falconet, Denis [Laboratoire de Physiologie Cellulaire et Végétale, UMR 5168, CEA-CNRS-INRA-Univ. Grenoble Alpes, Grenoble (France); Vertes, Akos, E-mail: vertes@gwu.edu [Department of Chemistry, W.M. Keck Institute for Proteomics Technology and Applications, The George Washington University, Washington, DC 20052 (United States)

    2016-01-01

    Biochemical processes rely on elaborate networks containing thousands of compounds participating in thousands of reaction. Rapid turnover of diverse metabolites and lipids in an organism is an essential part of homeostasis. It affects energy production and storage, two important processes utilized in bioengineering. Conventional approaches to simultaneously quantify a large number of turnover rates in biological systems are currently not feasible. Here we show that pulse-chase analysis followed by laser ablation electrospray ionization mass spectrometry (LAESI-MS) enable the simultaneous and rapid determination of metabolic turnover rates. The incorporation of ion mobility separation (IMS) allowed an additional dimension of analysis, i.e., the detection and identification of isotopologs based on their collision cross sections. We demonstrated these capabilities by determining metabolite, lipid, and peptide turnover in the photosynthetic green algae, Chlamydomonas reinhardtii, in the presence of {sup 15}N-labeled ammonium chloride as the main nitrogen source. Following the reversal of isotope patterns in the chase phase by LAESI-IMS-MS revealed the turnover rates and half-lives for biochemical species with a wide range of natural concentrations, e.g., chlorophyll metabolites, lipids, and peptides. For example, the half-lives of lyso-DGTS(16:0) and DGTS(18:3/16:0), t{sub 1/2} = 43.6 ± 4.5 h and 47.6 ± 2.2 h, respectively, provided insight into lipid synthesis and degradation in this organism. Within the same experiment, half-lives for chlorophyll a, t{sub 1/2} = 24.1 ± 2.2 h, and a 2.8 kDa peptide, t{sub 1/2} = 10.4 ± 3.6 h, were also determined. - Highlights: • High-throughput pulse-chase analysis using direct sampling of biological cells. • Ion mobility separation for the elucidation of isotopologs. • Identification of isotopologs in difference heat plots of DT vs. m/z. • Simultaneous determination of turnover rates for lipids and

  20. Revival and emended description of 'Mycobacterium paraffinicum' Davis, Chase and Raymond 1956 as Mycobacterium paraffinicum sp. nov., nom. rev.

    Science.gov (United States)

    Toney, Nadege; Adekambi, Toidi; Toney, Sean; Yakrus, Mitchell; Butler, W Ray

    2010-10-01

    The omission of the name 'Mycobacterium paraffinicum' from the Approved Lists of Bacterial Names was due to phenotypic confusion surrounding a close relationship with Mycobacterium scrofulaceum. Correspondingly, 'M. paraffinicum' strains grew slowly in > 7 days, stained acid-alcohol-fast and produced yellow-pigmented, smooth, waxy colonies in the dark at an optimal temperature of 35°C. However, 'M. paraffinicum' strains demonstrated no activity for urease, nicotinamidase or pyrazinamidase and lacked growth at 42°C, unlike M. scrofulaceum. The mycolic acid pattern, as determined by HPLC, clustered 'M. paraffinicum' with M. scrofulaceum, Mycobacterium avium and Mycobacterium parascrofulaceum. Strains were fully susceptible to linezolid, rifabutin, clarithromycin and amikacin. Examination of the historical reference strain of 'M. paraffinicum', ATCC 12670, and five additional isolates using comparative studies with 16S rRNA, hsp65 and rpoB gene and concatenated sequences showed that they formed a tight taxonomic group that was distinct from similar non-tuberculous mycobacteria. Multilocus enzyme electrophoresis (MEE) analysis confirmed a close association of the five additional isolates with the reference strain of 'M. paraffinicum' with a genetic distance of 0.12 and showed that all six strains were distinct from other closely related species. These genetic results provided unambiguous evidence of the uniqueness of this slowly growing, scotochromogenic species and supported the revival of the name as Mycobacterium paraffinicum (ex Davis, Chase and Raymond 1956) sp. nov., nom. rev. We propose the previously deposited reference strain ATCC 12670(T) =DSM 44181(T) =NCIMB 10420(T), located in collections worldwide, as the type strain.

  1. Carnivorous dinocephalian from the Middle Permian of Brazil and tetrapod dispersal in Pangaea.

    Science.gov (United States)

    Cisneros, Juan Carlos; Abdala, Fernando; Atayman-Güven, Saniye; Rubidge, Bruce S; Şengörc, A M Celâl; Schultz, Cesar L

    2012-01-31

    The medial Permian (~270-260 Ma: Guadalupian) was a time of important tetrapod faunal changes, in particular reflecting a turnover from pelycosaurian- to therapsid-grade synapsids. Until now, most knowledge on tetrapod distribution during the medial Permian has come from fossils found in the South African Karoo and the Russian Platform, whereas other areas of Pangaea are still poorly known. We present evidence for the presence of a terrestrial carnivorous vertebrate from the Middle Permian of South America based on a complete skull. Pampaphoneus biccai gen. et sp. nov. was a dinocephalian "mammal-like reptile" member of the Anteosauridae, an early therapsid predator clade known only from the Middle Permian of Russia, Kazakhstan, China, and South Africa. The genus is characterized, among other features, by postorbital bosses, short, bulbous postcanines, and strongly recurved canines. Phylogenetic analysis indicates that the Brazilian dinocephalian occupies a middle position within the Anteosauridae, reinforcing the model of a global distribution for therapsids as early as the Guadalupian. The close phylogenetic relationship of the Brazilian species to dinocephalians from South Africa and the Russian Platform suggests a closer faunistic relationship between South America and eastern Europe than previously thought, lending support to a Pangaea B-type continental reconstruction.

  2. The continental Permian-Triassic boundary in the Netherlands: Implications for the geomagnetic polarity time scale

    NARCIS (Netherlands)

    Szurlies, M.; Geluk, M.C.; Krijgsman, W.; Kürschner, W.M.

    2012-01-01

    In Central and NW Europe, the transition from the Permian to the Triassic (i.e., the Zechstein–Buntsandstein boundary interval) is developed mainly in red bed facies. This continental sedimentary succession is marked by relatively high sedimentation rates providing a high temporal resolution

  3. The main fish communities of the limnic Permian and Carboniferous basins of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Zajíc, Jaroslav

    33-34, - (2006), s. 99-101. ISBN 80-210-4097-1. ISSN 1211-281X. [Paleontological Conference /7./. Brno, 19.10.2006-20.10.2006] Institutional research plan: CEZ:AV0Z30130516 Keywords : ichthyofaunae * Upper Carboniferous * Lower Permian Subject RIV: EG - Zoology

  4. Biogenic silica microfossils in sediments of the Permian - Carboniferous Unayzah Formation, Saudi Arabia

    NARCIS (Netherlands)

    Garming, J.F.L.; Franks, S.G.; Cremer, H.; Abbink, O.A.

    2010-01-01

    Biogenic silica particles (BSPs) have been discovered in sediments of the Permian - Carboniferous Unayzah Formation of Saudi Arabia. The BSPs are extracted from sediments that are generally barren of macro- or microfossils. BSPs have been found in the Basal Khuff Clastics (BKC), and the Unayzah A,

  5. A Record of Rotaloid Foraminifera from the Upper Permian-Lower ...

    African Journals Online (AJOL)

    PRABHAS PANDE

    INTRODUCTION. In the history of organic evolution, the end of Palaeozoic Era was marked by the conspicuous event of mass extinctions. Amongst foraminifera, as many as fourteen families became extinct. (Loeblich and Tappan, 1964) during the Permian Period and many new families evolved in the. Mesozoic. There is a ...

  6. Permian fauna of the Krkonoše Piedmont Basin (Bohemian Massif, Central Europe)

    Czech Academy of Sciences Publication Activity Database

    Zajíc, Jaroslav

    2014-01-01

    Roč. 70, 3/4 (2014), s. 131-142 ISSN 0036-5343 Institutional support: RVO:67985831 Keywords : faunal lists * palaeogeography * palaeoenvironment * stratigraphy * Early Permian * Krkonoše Piedmont Basin * Bohemian Massif Subject RIV: DB - Geology ; Mineralogy

  7. A tale of two extinctions : converging end-Permian and end-Triassic scenarios

    NARCIS (Netherlands)

    van de Schootbrugge, Bas; Wignall, Paul B.

    The end-Permian (c. 252 Ma) and end-Triassic (c. 201 Ma) mass-extinction events are commonly linked to the emplacement of the large igneous provinces of the Siberia Traps and Central Atlantic Magmatic Province, respectively. Accordingly, scenarios for both extinctions are increasingly convergent and

  8. Anatomy of a Permian Erg sequence: the De La Cuesta Formation (northwestern Argentina)

    International Nuclear Information System (INIS)

    Spalletti, L.; Limarino, C.; Colombo, F.

    2010-01-01

    This work is about the Permian red beds of the La Cuesta Formation (Sierra de Narvaez, northwestern Argentina) which is composed of sandstones associated with mud stones and subordinate conglomerates. The sediments obtained from the interaction between aeolian and ephemeral fluvial systems, are represented by aeolian dune, dry aeolian inter dune and aeolian sand sheet, mud flat, wet aeolian inter dune, and fluvial deposits

  9. Lower permian reef-bank bodies’ characterization in the pre-caspian basin

    Science.gov (United States)

    Wang, Zhen; Wang, Yankun; Yin, Jiquan; Luo, Man; Liang, Shuang

    2018-02-01

    Reef-bank reservoir is one of the targets for exploration of marine carbonate rocks in the Pre-Caspian Basin. Within this basin, the reef-bank bodies were primarily developed in the subsalt Devonian-Lower Permian formations, and are dominated by carbonate platform interior and margin reef-banks. The Lower Permian reef-bank present in the eastern part of the basin is considered prospective. This article provides a sequence and sedimentary facies study utilizing drilling and other data, as well as an analysis and identification of the Lower Permian reef-bank features along the eastern margin of the Pre-Caspian Basin using sub-volume coherence and seismic inversion techniques. The results indicate that the sub-volume coherence technique gives a better reflection of lateral distribution of reefs, and the seismic inversion impedance enables the identification of reef bodies’ development phases in the vertical direction, since AI (impedance) is petrophysically considered a tool for distinguishing the reef limestone and the clastic rocks within the formation (limestone exhibits a relatively high impedance than clastic rock). With this method, the existence of multiple phases of the Lower Permian reef-bank bodies along the eastern margin of the Pre-Caspian Basin has been confirmed. These reef-bank bodies are considered good subsalt exploration targets due to their lateral connectivity from south to north, large distribution range and large scale.

  10. Marine anoxia and delayed Earth system recovery after the end-Permian extinction.

    Science.gov (United States)

    Lau, Kimberly V; Maher, Kate; Altiner, Demir; Kelley, Brian M; Kump, Lee R; Lehrmann, Daniel J; Silva-Tamayo, Juan Carlos; Weaver, Karrie L; Yu, Meiyi; Payne, Jonathan L

    2016-03-01

    Delayed Earth system recovery following the end-Permian mass extinction is often attributed to severe ocean anoxia. However, the extent and duration of Early Triassic anoxia remains poorly constrained. Here we use paired records of uranium concentrations ([U]) and (238)U/(235)U isotopic compositions (δ(238)U) of Upper Permian-Upper Triassic marine limestones from China and Turkey to quantify variations in global seafloor redox conditions. We observe abrupt decreases in [U] and δ(238)U across the end-Permian extinction horizon, from ∼3 ppm and -0.15‰ to ∼0.3 ppm and -0.77‰, followed by a gradual return to preextinction values over the subsequent 5 million years. These trends imply a factor of 100 increase in the extent of seafloor anoxia and suggest the presence of a shallow oxygen minimum zone (OMZ) that inhibited the recovery of benthic animal diversity and marine ecosystem function. We hypothesize that in the Early Triassic oceans-characterized by prolonged shallow anoxia that may have impinged onto continental shelves-global biogeochemical cycles and marine ecosystem structure became more sensitive to variation in the position of the OMZ. Under this hypothesis, the Middle Triassic decline in bottom water anoxia, stabilization of biogeochemical cycles, and diversification of marine animals together reflect the development of a deeper and less extensive OMZ, which regulated Earth system recovery following the end-Permian catastrophe.

  11. Phosphatic Permian rocks of the Adobe Range, Nevada, and their environment of deposition

    Science.gov (United States)

    Ketner, Keith Brindley

    1979-01-01

    Permian sedimentary rocks in the Adobe range, northern Nevada, are phosphatic, and although the particles of phosphate are relatively more disseminated, they closely resemble the rocks of the Phosphoria Formation. In the northern Adobe Range, where the entire Permian sequence is approximately correlative with the Phosphoria Formation, it is 200 m thick and averages 1.7 percent P2O5 . In the southern Adobe Range, the Permian sequence is more than 1,700 m thick, and the upper half which is roughly correlative with the Phosphoria Formation averages more than 2 percent P2O5. Some thin beds in rocks of Permian age contain more than 20 percent P2O5. Phosphatic rocks of the Adobe Range were deposited in shallow water among islands in the western part of the epicontinental Phosphoria sea. The continental margin and the open ocean lay far to the west. At the same time, the Phosphoria Formation was being deposited in the eastern and central parts of the Phosphoria sea. Theories based on the work of Kasakov done in 1937 relating phosphate deposition directly to sites of upwelling oceanic waters are questioned. Nondeposition of diluent materials such as detritus and carbonate is probably of more importance in producing phosphate in economic concentrations than is geographic position with respect to upwelling waters.

  12. The fungal and acritarch events as time markers for the latest Permian mass extinction: An update

    Directory of Open Access Journals (Sweden)

    Michael R. Rampino

    2018-01-01

    Full Text Available The latest Permian extinction (252 Myr ago was the most severe in the geologic record. On land, widespread Late Permian gymnosperm/seed-fern dominated forests appear to have suffered rapid and almost complete destruction, as evidenced by increased soil erosion and changes in fluvial style in deforested areas, signs of wildfires, replacement of trees by lower plants, and almost complete loss of peat-forming and fire-susceptible vegetation. Permian–Triassic boundary strata at many sites show two widespread palynological events in the wake of the forest destruction: The fungal event, evidenced by a thin zone with >95% fungal cells (Reduviasporonites and woody debris, found in terrestrial and marine sediments, and the acritarch event, marked by the sudden flood of unusual phytoplankton in the marine realm. These two events represent the global temporary explosive spread of stress-tolerant and opportunistic organisms on land and in the sea just after the latest Permian disaster. They represent unique events, and thus they can provide a time marker in correlating latest Permian marine and terrestrial sequences.

  13. The Saint Martin de Belleville syncline and its uraniferous permian sandstone

    International Nuclear Information System (INIS)

    Schade, Johannes

    1983-01-01

    This dissertation (these de specialite) is a study of the geology of the St.Martin d.B. syncline and the uranium prospect 'le Cochet' in the Carboniferous Brianconnais Zone of Savoy. Stratigraphy and sedimentology: This syncline presents continental detrital sediments ranging from U.Carboniferous to L.Triassic. In the U.Carboniferous, magmatic activity begins with the Moriaz Layers acid volcanics that are considered as a lateral equivalent of the Stephanian Courchevel Conglomerates. In Permian times, parts of an alluvial fan seem to occupy the north of the study area (gray and green conglomeratic sandstone). Southwards these inter-finger with flood plain sediments (red slate) including a locally oolitic limestone. Volcanic detritus is important in the Permian. Tourmalinite pebbles are frequent and seem to be related to the regional Permian magmatism. Albitization of feldspars is general in the Carboniferous and the Permian. The Permo-triassic typically shows microcline bearing dolomitic sandstones. In the Scythian quartzites orthoclase is the dominant feldspar. The quartzites are overlain by L.Triassic evaporites identified by the sulfur isotope ratio of their gypsum. The morphology of the zircons in the sandstones has been investigated using the typological method of J.P. Pupin. Regional Permian magmatism apparently produces volcanics of the calc-alkalic and tholeiitic series as well as a high level granitic intrusion of anatectic origin. The uranium occurrences are strata-bound on a kilometric and hecto-metric scale. They are developed almost exclusively in the gray variety of the Permian sandstones whose gray and red varieties are always barren. Within this unit, the mineralization impregnates irregularly distributed lenses and pods of coal material. Uranium is accompanied by vanadium occurring as roscoelite. The association U-V, of bio-philic character, reflects the concentration in the sedimentary environment and argues for a quite indirect relation with the

  14. Permian-Triassic palynofacies and chemostratigraphy in a core recovered from central Spitsbergen.

    Science.gov (United States)

    van Soelen, Els; Hasic, Edi; Planke, Sverre; Svensen, Henrik; Sleveland, Arve; Midtkandal, Ivar; Twitchett, Richard; Kürschner, Wolfram

    2017-04-01

    The Late Permian biotic crisis is one of the most severe extinction events in the history of the Earth, affecting both terrestrial and marine environments. A large igneous province (LIP) in Siberia is thought to be linked with this global event; however, correlation between the volcanic event and the biotic crisis is difficult and requires well dated and high resolution Permian-Triassic boundary successions from the Arctic region. The Svalbard end-Permian drilling project is aimed at improved correlation of the Permian-Triassic sections in Svalbard with the Siberian Traps. The core was collected from Deltadalen, in central Spitsbergen, with additional samples collected from an outcrop close to the drilling site. As part of this collaborative project, carbon isotope geochemistry, palynofacies and palynomorphs were studied in order to learn more about the biostratigraphy and to understand changes in the source(s) of organic matter. Objectives were to reconstruct the paleo-environment; to correlate the core with other sites on Svalbard, and with global records; and to identify and characterize the Late Permian extinction event in the core. A carbon isotope shift is an important global stratigraphic marker in the latest Permian and occurs near the base of the Vikinghøgda Formation in the Deltadalen core, where bulk rock values change from -24.5 to -32.7‰. Palynomorph preservation was generally poor in both core and outcrop samples which prevented detailed examination of species and limited their usefulness for biostratigraphy. Still, palynofacies were useful for correlative purposes. AOM (amorphous organic matter) in the core increases at the lithological change from sandstones to siltstones, and is indicative of anoxic conditions. Similar high levels of AOM in the outcrop samples can be correlated with the core. Palynological analyses show that the spore/pollen ratio starts to increase before the negative shift in the isotope curve. Such an increase in spore

  15. Relaciones citotaxonómicas entre Paspalum almum Chase y P. hexastachyum Parodi (Gramineae

    Directory of Open Access Journals (Sweden)

    Camilo L Quarín

    1974-01-01

    Full Text Available El autor describe el grupo Alrna del género Paspalum, sobre la base de un manuscrito de Parodi y Nicora (1966. Lleva a cabo un estudio morfológico y citológico de las dos especies que constituyen este grupo: P.almum Chase y Parodi P.hexastachyurn.  P.alrnum presenta veinticuatro cromosomas somáticos y en Metafase I, se comporta como una especie autotetraploide formada a 6 IV's. Aquí se informa, por primera vez, un recuento cromosómico de P.hexastachyum (2n = 12. Este es el número más bajo, conocido para el género Paspalum, lo que confirma la presencia del número básico x = 6, a diferencia del más frecuente en el género, que es x = 10.

  16. Chasing Science at Sea: Racing Hurricanes, Stalking Sharks, and Living Undersea With Ocean Experts

    Science.gov (United States)

    Lee, Cindy

    2008-12-01

    Ellen Prager's new book, Chasing Science at Sea, is a personal account of why fieldwork is so important in many areas of ocean science, and how exciting that fieldwork can be. Prager has interwoven her own story of studying carbonates at the interface between biology and geology with stories from friends and colleagues. Storm stories and up-close-and-personal encounters with ocean creatures such as reef squid, marine iguanas, and whales abound. Throughout the book, she emphasizes the idea that the combination of observations and serendipity plays a critical role in science, and she gives examples of where this combination has led to especially important discoveries (e.g., that of hydrothermal vent organisms).

  17. Behaviorism Makes Its Debut: A Review of Lattal and Chase's Behavior Theory and Philosophy

    Science.gov (United States)

    Zuriff, G.E

    2005-01-01

    Behavior Theory and Philosophy, masterfully edited by Lattal and Chase, is a collection of 21 papers by major behaviorists, presented and discussed at a conference on the intersection of philosophy and behavior analysis held at West Virginia University in 2000. The chapters in Part I are devoted to philosophy of science (causality, constructs, theory, explanation, reductionism) and the relations among behavior analysis and several contemporary philosophical movements (humanism, empiricism, pragmatism, selectionism, analytic philosophy). Part II examines behavior-analytic interpretations of mentalistic concepts (intention, imagination, ethics, cognition). Part III presents extensions and applications of basic research in behavior analysis (verbal behavior, creativity, development, education, disability, and corporate culture). The publication of this book signals that behaviorism has developed mature philosophical foundations.

  18. Fibers and cylinders of cryptomelane-hollandite in Permian bedded salt, Palo Duro Basin, Texas

    International Nuclear Information System (INIS)

    Belkin, H.E.; Libelo, E.L.

    1987-01-01

    Fibers and thin-walled, hollow cylinders of cryptomelane-hollandite have been found in both the chevron and the clear salt from various drill cores in Permian bedded salt from the Palo Duro Basin, Texas. The authors have found fibers or cylinders from only the lower San Andres Formation units 4 and 5, the upper San Andres Formation, and the Salado-Transill salt. The fibers are inorganic, light to dark reddish brown, pleochroic, highly birefringent, filamentary single crystals, < 1 to ∼ 5 μm in diameter, with length-to-diameter ratios of at least 20:1. The fibers can be straight and/or curved, can bifurcate, can form loops, waves or spirals, and can be isolated or in parallel groups. Detailed petrographic analyses show no evidence for recrystallization or deformation of the enclosing salt after fiber formation. Although the authors observations do not provide a definitive explanation for fiber origin, they suggest that the fibers grew in situ by a solid-state diffusional process at low temperatures. The cylinders are pleochroic, highly birefringent, light to dark reddish brown, hollow, thin-walled, open-ended right cylinders, having a 1- to 2-μm wall thickness and variable lengths and diameters. There also appear to be single crystals of cryptomelane-hollandite, but these are found almost entirely in fluid inclusions in the chevron and clear salt. Their presence in the primary halite suggests that they were formed contemporaneously with the chevron structure and were accidentally trapped in the fluid inclusions. The observation of cylinders partially or completely enclosed by salt stratigraphically above large fluid inclusions suggests that natural downward fluid-inclusion migration has occurred, in response to the geothermal gradient

  19. Ostracods (Crustacea associated with microbialites across the Permian-Triassic boundary in Dajiang (Guizhou Province, South China

    Directory of Open Access Journals (Sweden)

    Marie-Beatrice FOREL

    2012-08-01

    Full Text Available 26 samples were processed for a taxonomic study of ostracods from the Upper Permian (Changhsingian - Lower Triassic (Griesbachian interval of the Dajiang section, Guizhou Province, South China. 112 species belonging to 27 genera are recognized. Five new species are described: Acratia candyae sp. nov, Bairdia adelineae sp. nov., Bairdia? huberti sp. nov., Bairdia jeromei sp. nov., Orthobairdia jeanlouisi sp. nov. The unexpected survival faunas associated with microbial formations in the aftermath of the end-Permian extinction are documented for the first time. Ostracod biodiversity variations and palaeo-environmental modifications associated with microbial growth through the Permian-Triassic boundary (PTB are discussed.

  20. New results of microfaunal and geochemical investigations in the Permian-Triassic boundary interval from the Jadar Block (NW Serbia)

    Science.gov (United States)

    Sudar, Milan N.; Kolar-Jurkovšek, Tea; Nestell, Galina P.; Jovanović, Divna; Jurkovšek, Bogdan; Williams, Jeremy; Brookfield, Michael; Stebbins, Alan

    2018-04-01

    Detail results of microfaunal, sedimentological and geochemical investigations are documented from a newly discovered section of the Permian-Triassic boundary (PTB) interval in the area of the town of Valjevo (northwestern Serbia). The presence of various and abundant microfossils (conodonts, foraminifers, and ostracodes) found in the Upper Permian "Bituminous limestone" Formation enabled a determination of the Changhsingian Hindeodus praeparvus conodont Zone. This paper is the first report of latest Permian strata from the region, as well as from all of Serbia, where the PTB interval sediments have been part of a complex/integrated study by means of biostratigraphy and geochemistry.

  1. The Cannery Formation--Devonian to Early Permian arc-marginal deposits within the Alexander Terrane, Southeastern Alaska

    Science.gov (United States)

    Karl, Susan M.; Layer, Paul W.; Harris, Anita G.; Haeussler, Peter J.; Murchey, Benita L.

    2011-01-01

    The Cannery Formation consists of green, red, and gray ribbon chert, siliceous siltstone, graywacke-chert turbidites, and volcaniclastic sandstone. Because it contains early Permian fossils at and near its type area in Cannery Cove, on Admiralty Island in southeastern Alaska, the formation was originally defined as a Permian stratigraphic unit. Similar rocks exposed in Windfall Harbor on Admiralty Island contain early Permian bryozoans and brachiopods, as well as Mississippian through Permian radiolarians. Black and green bedded chert with subordinate lenses of limestone, basalt, and graywacke near Kake on Kupreanof Island was initially correlated with the Cannery Formation on the basis of similar lithology but was later determined to contain Late Devonian conodonts. Permian conglomerate in Keku Strait contains chert cobbles inferred to be derived from the Cannery Formation that yielded Devonian and Mississippian radiolarians. On the basis of fossils recovered from a limestone lens near Kake and chert cobbles in the Keku Strait area, the age of the Cannery Formation was revised to Devonian and Mississippian, but this revision excludes rocks in the type locality, in addition to excluding bedded chert on Kupreanof Island east of Kake that contains radiolarians of Late Pennsylvanian and early Permian age. The black chert near Kake that yielded Late Devonian conodonts is nearly contemporaneous with black chert interbedded with limestone that also contains Late Devonian conodonts in the Saginaw Bay Formation on Kuiu Island. The chert cobbles in the conglomerate in Keku Strait may be derived from either the Cannery Formation or the Saginaw Bay Formation and need not restrict the age of the Cannery Formation, regardless of their source. The minimum age of the Cannery Formation on both Admiralty Island and Kupreanof Island is constrained by the stratigraphically overlying fossiliferous Pybus Formation, of late early and early late Permian age. Because bedded radiolarian

  2. Late Permian rivers draining the uplifted Cape Fold Belt: magnetostratigraphy and detrital thermochronology of Karoo Basin sediments

    Science.gov (United States)

    Tohver, E.; Schmieder, M.; Arosio, R.; Lanci, L.; Jourdan, F.; Wilson, A.; Ratcliffe, K.; Payenberg, T.; Flint, S.

    2017-12-01

    The Cape Fold Belt and Karoo Basin of southern Africa formed during the Permian orogeny that affected the 13,000 km southern margin of the Gondwanan continent. In this report, we synthesize new and recent magnetostratigraphic and geochronologic data to establish a chronostratigraphic framework for Karoo Basin sedimentation for comparison with the thermal/exhumation history of the Cape Fold Belt. The source-sink model is evaluated using new data from detrital muscovite and zircon from 2 km composite section of fluvial sandstone and mudstones deposited at ca.275 - 260 Ma. Coherent age populations of detrital zircon grains indicate rapid incorporation of contemporary volcanic ashbeds into the sedimentary record. In contrast, cooling age distributions of detrital muscovite are typically ca. 5 - 10 Ma older than the age of deposition; similar lag times are observed from modern sediments in active mountain belts. Trace element geochemical signatures demonstrate a clear shift towards crustal recycling via headland erosion in the Beaufort Group relative to the underlying Ecca Group. These observations pinpoint the age of uplift for the Cape Fold Belt, which began to function as the major sediment source for the foreland Karoo Basin with the deposition of the uppermost Ecca Group and basal Beaufort Group.

  3. Antarctic glossopterid diversity on a local scale: the presence of multiple megasporophyll genera, Upper Permian, Mt. Achernar, Transantarctic Mountains, Antarctica.

    Science.gov (United States)

    Ryberg, Patricia E; Taylor, Edith L; Taylor, Thomas N

    2012-09-01

    The glossopterids are a group of plants that thrived during a time of global warming similar to what is happening on the Earth today as well as the transition from archaic plant groups to the ancestors of modern groups. The diversity of the glossopterid clade is based on the megasporangiate structures assigned to the group, because the vegetative and pollen-bearing structures vary little. The presence of numerous reproductive genera from a single Upper Permian locality in the central Transantarctic Mountains provides important data on local glossopterid diversity in Antarctica. Impression/compression fossils were imaged with a Leica 5000C digital camera on a dissecting microscope or a Fujifilm FinePix S1pro digital camera. Two megasporangiate taxa are described: Scutum leiophyllum, which represents the first confirmed record of the genus in Antarctica, and Lidgettoniopsis ramulus, a new morphology consisting of a pinnate structure with oppositely attached megasporophylls. Plumsteadia ovata specimens indicate that this genus can be larger than previously recorded and illustrate the vegetative surface with a distinct midrib. The presence of a laminar, multiovulate structure and a pinnate structure at the same site indicates that local-level glossopterid diversity in Antarctica is greater than previously hypothesized. The discovery of a new megasporophyll morphology in Antarctica (confirming the presence of three distinctive morphologies on the continent) shows that Antarctic glossopterid heterogeneity is on a par with other Gondwanan continents. The diversity of the Antarctic landscape reveals that high polar latitudes can sustain a diverse ecosystem during times of global warming.

  4. Palaeomagnetism of the Early Permian Mount Leyshon Intrusive Complex and Tuckers Igneous Complex, North Queensland, Australia

    Science.gov (United States)

    Clark, D. A.; Lackie, M. A.

    2003-06-01

    This study provides reliable, precisely defined and well-dated Early Permian (286 +/- 6 Ma) palaeomagnetic poles for Australia from the Mount Leyshon Intrusive Complex (MLIC) and the Tuckers Igneous Complex (TIC). Both complexes are associated with prominent negative magnetic anomalies, indicating the presence of rocks carrying stable remanence of reverse polarity, with a Koenigsberger ratio greater than unity. The characteristic remanence carried by the intrusive phases and by locally remagnetized, contact-metamorphosed host rocks is always of reverse polarity, consistent with acquisition during the Permo-Carboniferous (Kiaman) Reverse Superchron. The corresponding palaeopoles confirm that Australia occupied high latitudes in the Early Permian. The pole positions are: MLIC: lat. = 43.2 °S, long. = 137.3 °E dp = 6.0°, dm = 6.4° Q= 6; TIC: lat. = 47.5 °S, long. = 143.0 °E, dp = 6.0°, dm = 6.6° Q= 6. Permian palaeomagnetic overprinting is detectable at considerable distances from the MLIC (2-3 km), well beyond the zone of visible alteration. The primary nature of the Early Permian palaeomagnetic signature is established by full baked contact/aureole tests at both localities. Other new data from Australia are consistent with the poles reported here. Comparison of the Australian, African and South American Apparent Polar Wander Paths (APWP) suggests that mean Permian and Triassic poles from West Gondwana, particularly from South America, are biased by remagnetization in the Jurassic-Cretaceous and that the Late Palaeozoic-Mesozoic APWP for Gondwana is best defined by Australian data. The Australian APWP exhibits substantial movement through the Mesozoic. Provided only that the time-averaged palaeofield was zonal, the Early Triassic palaeomagnetic data from Australia provide an important palaeogeographic constraint that the south geographic pole was within, or very close to, SE Australia around 240 Ma. The new Early Permian poles are apparently more consistent

  5. Permian ultrafelsic A-type granite from Besar Islands group, Johor ...

    Indian Academy of Sciences (India)

    X = dark brown and Y = straw yellow. The tex- ture suggests that the mineral was early in origin because it ... transparent, colourless to pale brown and showed oscillatory ...... 96–105. Ghani A A 2006 Batuan volkanik dari Pulau Tinggi dan.

  6. A Vicious Cycle: A Cross-Sectional Study of Canine Tail-Chasing and Human Responses to It, Using a Free Video-Sharing Website

    Science.gov (United States)

    Burn, Charlotte C.

    2011-01-01

    Tail-chasing is widely celebrated as normal canine behaviour in cultural references. However, all previous scientific studies of tail-chasing or ‘spinning’ have comprised small clinical populations of dogs with neurological, compulsive or other pathological conditions; most were ultimately euthanased. Thus, there is great disparity between scientific and public information on tail-chasing. I gathered data on the first large (n = 400), non-clinical tail-chasing population, made possible through a vast, free, online video repository, YouTube™. The demographics of this online population are described and discussed. Approximately one third of tail-chasing dogs showed clinical signs, including habitual (daily or ‘all the time’) or perseverative (difficult to distract) performance of the behaviour. These signs were observed across diverse breeds. Clinical signs appeared virtually unrecognised by the video owners and commenting viewers; laughter was recorded in 55% of videos, encouragement in 43%, and the commonest viewer descriptors were that the behaviour was ‘funny’ (46%) or ‘cute’ (42%). Habitual tail-chasers had 6.5+/−2.3 times the odds of being described as ‘Stupid’ than other dogs, and perseverative dogs were 6.8+/−2.1 times more frequently described as ‘Funny’ than distractible ones were. Compared with breed- and age-matched control videos, tail-chasing videos were significantly more often indoors and with a computer/television screen switched on. These findings highlight that tail-chasing is sometimes pathological, but can remain untreated, or even be encouraged, because of an assumption that it is ‘normal’ dog behaviour. The enormous viewing figures that YouTube™ attracts (mean+/−s.e. = 863+/−197 viewings per tail-chasing video) suggest that this perception will be further reinforced, without effective intervention. PMID:22096487

  7. A vicious cycle: a cross-sectional study of canine tail-chasing and human responses to it, using a free video-sharing website.

    Directory of Open Access Journals (Sweden)

    Charlotte C Burn

    Full Text Available Tail-chasing is widely celebrated as normal canine behaviour in cultural references. However, all previous scientific studies of tail-chasing or 'spinning' have comprised small clinical populations of dogs with neurological, compulsive or other pathological conditions; most were ultimately euthanased. Thus, there is great disparity between scientific and public information on tail-chasing. I gathered data on the first large (n = 400, non-clinical tail-chasing population, made possible through a vast, free, online video repository, YouTube™. The demographics of this online population are described and discussed. Approximately one third of tail-chasing dogs showed clinical signs, including habitual (daily or 'all the time' or perseverative (difficult to distract performance of the behaviour. These signs were observed across diverse breeds. Clinical signs appeared virtually unrecognised by the video owners and commenting viewers; laughter was recorded in 55% of videos, encouragement in 43%, and the commonest viewer descriptors were that the behaviour was 'funny' (46% or 'cute' (42%. Habitual tail-chasers had 6.5+/-2.3 times the odds of being described as 'Stupid' than other dogs, and perseverative dogs were 6.8+/-2.1 times more frequently described as 'Funny' than distractible ones were. Compared with breed- and age-matched control videos, tail-chasing videos were significantly more often indoors and with a computer/television screen switched on. These findings highlight that tail-chasing is sometimes pathological, but can remain untreated, or even be encouraged, because of an assumption that it is 'normal' dog behaviour. The enormous viewing figures that YouTube™ attracts (mean+/-s.e. = 863+/-197 viewings per tail-chasing video suggest that this perception will be further reinforced, without effective intervention.

  8. A REMAINING OPEN PALEOGEOGRAPHY OF PALEO-ASIAN OCEAN BY EARLY PERMIAN: PALEOMAGNETIC CONSTRAINTS FROM THE PERMIAN VOLCANIC ROCKS IN MIDDLE-EAST INNER MONGOLIA, NE CHINA

    Directory of Open Access Journals (Sweden)

    Donghai Zhang

    2017-01-01

    Full Text Available We report a paleomagnetic investigation on Permian volcanic rocks in the middle-east Inner Mongolia, NE China, aiming to puzzle out the timing and position of the final closure of the eastern Paleo-Asian ocean (PAO and further to better understand tectonic evolution of the Central Asian Orogenic Belt (CAOB. Two pre-folding characteristic components are isolated from the Sanmianjing and Elitu formations (~283–266 Ma in the northern margin of the North China block (NMNCB and the Dashizhai Formation (~280 Ma in the Songliao-Xilinhot block (SXB, respectively.

  9. Microfacies, Depositional environment and Sequence Stratigraphy of Upper Carboniferous- Lower Permian rocks from Ozbak-Kuh region (Zaladou Section, East Central Iran

    Directory of Open Access Journals (Sweden)

    Ali Ahmadi

    2016-01-01

    Full Text Available Zaladou section is located in Ozbak-Kuh mountains in the nourthen part of Tabas block and consist of shale, limy sandstone, limestone and dolomite. Continous relationship of Upper Carboniferous and Lower Permian deposits, is quite evident in Zaladou section. The lower boundry of this section is located on the Absheni formation of Sardar Group with disconformity surface, and upper boundry’s is covered by disconformity surface and bauxite horizon of Bagh-e-Vang formation. According to the lithological Characters and microscopic studies, tidal flat, lagoon, bar, tidal inlet and open marine sub-environment are identified for Zaladou section. Results of this study show that Zaladou section was deposited in silisiclastic-carbonate mix homoclinal ramp in late Carboniferous and in carbonate homoclinal ramp in early Permian. Field study, microfacies and analysis through the sequence led to recognition of main sequence surface, such as: sequence boundry, maximum flooding surface, marine flooding surface, system tracts and two depositional sequences.

  10. A latest Permian non-reef calcisponge fauna from Laibin, Guangxi, southern China and its significance

    Directory of Open Access Journals (Sweden)

    Ya-Sheng Wu

    2017-01-01

    Full Text Available A calcisponge fauna occurs in uppermost Permian Conodont Clarkina meishanensis yini zone of the sequence exposed in the vicinity of Laibin, Guangxi Zhuang Autonomous Region, southern China. The fauna is dominated by one thalamid species, Amblysiphonella vesiculosa de Koninck, 1863, and one new sclerosponge genus and species, Radiofibrosclera laibinensis gen. et sp. nov. They are associated with a few other accessory species, including the thalamid sponges Amblysiphonella laibinensis Deng, 1981, Colospongia sp., Polycystocoelia sp., and the inozoan sponge Acoelia discontinua sp. nov. Though the individuals are abundant, the species diversity is very low. Without common calcisponge components of Changhsingian reefal faunas, the assemblage is interpreted as not a reefal fauna. The water depth at which they dwelled was less than 105 m, and more probably less than 40 m. Its occurrence indicates a significant sea-level drop at the end of Late Permian Changhsingian Age.

  11. U-Th-Geochemistry of Permian and Triassic sediments of the Drauzug, Carinthia, Austria

    International Nuclear Information System (INIS)

    Kurat, G.; Korkisch, J.; Niedermayr, G.; Seemann, R.

    1976-05-01

    Chemical analysis of samples of Triassic and Permian rocks from the Drauzug, Carinthia and Austria was carried out. U concentration was measured by flurimetry, Th and Cu by spectrophotometry using Thoronol method or Arsenazo III method for Th, Fe by titrimetry and V, Ba, Sr by atomic absorption spectrophotometry. The average U concentration ranged from 0.8 to 4.6 ppm and the Th concentration from 3.2 to 15.6 ppm depending upon the mineral material. The quartzporphyries contained the highest concentration of both. It was concluded that the Permian-Triassic series are very similar to the equivalent deposits in Northern Italy. Assuming a lateral displacement, the former represent the Northern marginal part of the latter and therefore are inferior in thickness and thus not favourable for larger U mineralization

  12. Juvenile-adult habitat shift in permian fossil reptiles and amphibians.

    Science.gov (United States)

    Bakker, R T

    1982-07-02

    Among extant large reptiles, juveniles often occupy different habitats from those of adults or subadults and thus avoid competition with and predation from the older animals; small juveniles often choose cryptic habitats because they are vulnerable to a wide variety of predators. Evidence from fossil humeri and femora of Early Permian reptiles collected from sediments of several distinct habitats indicate that similar shifts in habitat occurred. Juvenile Dimetrodon seem to have favored cryptic habitats around swamp and swampy lake margins; adults favored open habitats on the floodplains. Similar patterns of habitat shift seem to be present in the reptile Ophiacodon and the amphibian Eryops and may have been common in fossil tetrapods of the Permian-Triassic.

  13. Subsurface Permian reef complexes of southern Tunisia: Shelf carbonate setting and paleogeographic implications

    Science.gov (United States)

    Zaafouri, Adel; Haddad, Sofiene; Mannaî-Tayech, Beya

    2017-05-01

    2-D seismic reflection sections, borehole data as well as published and unpublished data have been investigated to reconstruct the paleogeography of southern Tunisia during Middle to Late Permian times. Paleogeographical reconstruction based on the integration of petroleum well data and 2-D seismic facies interpretation shows three main depositional areas with very contrasting sedimentary pile. These are 1) a subsiding basin; 2) an outer shelf carbonate, and 3) an inner shelf carbonate. Based on typical electric responses of reef buildups to seismic wave, we shall urge that during Middle Permian times, the outer carbonate shelf was subject of reef barrier development. Lithology evidences from core samples show that reef framework correspond mainly to fossiliferous limestone and dolomite. The WNW-ESE recognized reef barrier led between latitudes 33° 10‧ 00″N and 33° 20‧ 00″N. The Tebaga of Medenine outcrop constitutes the northern-edge of this barrier. Westward it may be extended to Bir Soltane area whereas its extension eastward is still to be determined. Biogenic buildups took place preferentially over faulted Carboniferous and lower Paleozoic paleohighs resulting likely from the Hercynian orogeny. The subsiding basin is located north of Tebaga of Medenine outcrop where Upper Permian sedimentary sequence is made entirely of 4000 m deep marine green silty shale facies. These are ascribed to unorganized and chaotic reflectors. Inner carbonate shelf facies succession corresponds to a typical interbedding of shallow marine carbonate deposits, shale, dolomite, and anhydrite inducing parallel-layered of strong amplitude and good continuity reflectors. Also within the inner carbonate shelf patch reef or reef pinnacles have been identified based on their seismic signature particularly their low vertical development as compared to reef complexes. Southward, towards Sidi Toui area, the Upper Permian depositional sequence thins out and bears witness of land

  14. Volatile-organic molecular characterization of shale-oil produced water from the Permian Basin.

    Science.gov (United States)

    Khan, Naima A; Engle, Mark; Dungan, Barry; Holguin, F Omar; Xu, Pei; Carroll, Kenneth C

    2016-04-01

    Growth in unconventional oil and gas has spurred concerns on environmental impact and interest in beneficial uses of produced water (PW), especially in arid regions such as the Permian Basin, the largest U.S. tight-oil producer. To evaluate environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of PW. Although hydraulic fracturing has caused a significant increase in shale-oil production, there are no high-resolution organic composition data for the shale-oil PW from the Permian Basin or other shale-oil plays (Eagle Ford, Bakken, etc.). PW was collected from shale-oil wells in the Midland sub-basin of the Permian Basin. Molecular characterization was conducted using high-resolution solid phase micro extraction gas chromatography time-of-flight mass spectrometry. Approximately 1400 compounds were identified, and 327 compounds had a >70% library match. PW contained alkane, cyclohexane, cyclopentane, BTEX (benzene, toluene, ethylbenzene, and xylene), alkyl benzenes, propyl-benzene, and naphthalene. PW also contained heteroatomic compounds containing nitrogen, oxygen, and sulfur. 3D van Krevelen and double bond equivalence versus carbon number analyses were used to evaluate molecular variability. Source composition, as well as solubility, controlled the distribution of volatile compounds found in shale-oil PW. The salinity also increased with depth, ranging from 105 to 162 g/L total dissolved solids. These data fill a gap for shale-oil PW composition, the associated petroleomics plots provide a fingerprinting framework, and the results for the Permian shale-oil PW suggest that partial treatment of suspended solids and organics would support some beneficial uses such as onsite reuse and bio-energy production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Evidence for a western extension of the Angaran phytogeographic province in the Early Permian

    Energy Technology Data Exchange (ETDEWEB)

    Sunderlin, David [Department of the Geophysical Sciences, University of Chicago, Chicago, IL, 60637 (United States)

    2010-08-01

    A newly described Early Permian fossil plant assemblage in the Mt. Dall conglomerate in the Farewell terrane (Alaska Range, USA) is analyzed from a paleobiogeographic perspective. These data constitute the youngest paleontological dataset yet discovered in this terrane, represent the terrane's only predominantly terrestrial fossil assemblage, and are the only plant macrofossil remains of Early Permian age within a > 1500 km radius today. A suite of multivariate statistical analyses comparing the Mt. Dall paleoflora to similar age (Asselian-Artinskian) collections from the Angaran, Euramerican, and Cathaysian Permian phytogeographic provinces reveals that the Mt. Dall paleoflora has a paleobiogeographic affinity with Sub-Angaran plant fossil assemblages collected from Mongolia and the Primorye region of southeastern Russia. The paleoflora has dual importance in the construction and testing of hypotheses for which there are geographically and temporally few controls. First, these data may be used in association with other faunal and floral remains to test models of the assembly of Alaska, which seek, in part, an understanding of the paleogeographic and lithological origins of accreted terranes. That the Mt. Dall paleoflora indicates mixed Eurasia-North America paleobiogeographic affinity among individual taxa and plots in multivariate space with mid-latitude assemblages on northern Pangea may suggest deposition in that latitudinal belt. Second, contrary to the well-sampled fossil plant-bearing Permo-Carboniferous of the paleotropics and the northeastern temperate Pangean regions (Angaraland), terrestrial biome structure and vegetation type of northwestern Pangea are poorly known. This lack of understanding is due to the paucity of paleofloral collections from this region in this time period and the paleogeographic uncertainty of their position along the ancient active margin of Laurentia. The Mt. Dall paleoflora's phytogeographic affinity to paleobotanical

  16. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis?

    OpenAIRE

    Kershaw, Stephen; Crasquin, Sylvie; Li, Yue; Collin, Pierre-Yves; Forel, Marie-Béatrice

    2012-01-01

    Ocean acidification in modern oceans is linked to rapid increase in atmospheric CO2, raising concern about marine diversity, food security and ecosystem services. Proxy evidence for acidification during past crises may help predict future change, but three issues limit confidence of comparisons between modern and ancient ocean acidification, illustrated from the end-Permian extinction, 252 million years ago: (1) problems with evidence for ocean acidification preserved in sedimentary rocks, wh...

  17. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis?

    OpenAIRE

    Kershaw , Stephen; Crasquin , Sylvie; Li , Yue; Collin , Pierre-Yves; Forel , Marie-Béatrice

    2012-01-01

    International audience; Ocean acidification in modern oceans is linked to rapid increase in atmospheric CO 2 , raising concern about marine diversity, food security and ecosystem services. Proxy evidence for acidification during past crises may help predict future change, but three issues limit confidence of comparisons between modern and ancient ocean acidification, illustrated from the end-Permian extinction, 252 million years ago: (1) problems with evidence for ocean acidification preserve...

  18. Magnetic microsperules in Permian and Triassic bedded chert from Southwest Japan

    OpenAIRE

    Iwahashi,Junko; Yoshida,Masaru; Miono,Shigeyoshi; Santosh,Geetha; Santosh,M.

    1991-01-01

    Magnetic microspherules collected from the Permian and Triassic bedded cherts in Southwest Japan were studied. The size range, as estimated from 801 microspherules, vary from 3 to 100μm, with a peak size distribution between 10-20μm. Three broad shapes are recognized : spherical-, drop- and rocket-shaped, all categories including hollow particles. The surface textures as studied from scanning electron microscope show five dominant varieties : random mosaic, dendritic mosaic, feather crystal, ...

  19. Prolonged Permian–Triassic ecological crisis recorded by molluscan dominance in Late Permian offshore assemblages

    OpenAIRE

    Clapham, Matthew E.; Bottjer, David J.

    2007-01-01

    The end-Permian mass extinction was the largest biotic crisis in the history of animal life, eliminating as many as 95% of all species and dramatically altering the ecological structure of marine communities. Although the causes of this pronounced ecosystem shift have been widely debated, the broad consensus based on inferences from global taxonomic diversity patterns suggests that the shift from abundant brachiopods to dominant molluscs was abrupt and largely driven by the catastrophic effec...

  20. Volatile-organic molecular characterization of shale-oil produced water from the Permian Basin

    Science.gov (United States)

    Khan, Naima A.; Engle, Mark A.; Dungan, Barry; Holguin, F. Omar; Xu, Pei; Carroll, Kenneth C.

    2016-01-01

    Growth in unconventional oil and gas has spurred concerns on environmental impact and interest in beneficial uses of produced water (PW), especially in arid regions such as the Permian Basin, the largest U.S. tight-oil producer. To evaluate environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of PW. Although hydraulic fracturing has caused a significant increase in shale-oil production, there are no high-resolution organic composition data for the shale-oil PW from the Permian Basin or other shale-oil plays (Eagle Ford, Bakken, etc.). PW was collected from shale-oil wells in the Midland sub-basin of the Permian Basin. Molecular characterization was conducted using high-resolution solid phase micro extraction gas chromatography time-of-flight mass spectrometry. Approximately 1400 compounds were identified, and 327 compounds had a >70% library match. PW contained alkane, cyclohexane, cyclopentane, BTEX (benzene, toluene, ethylbenzene, and xylene), alkyl benzenes, propyl-benzene, and naphthalene. PW also contained heteroatomic compounds containing nitrogen, oxygen, and sulfur. 3D van Krevelen and double bond equivalence versus carbon number analyses were used to evaluate molecular variability. Source composition, as well as solubility, controlled the distribution of volatile compounds found in shale-oil PW. The salinity also increased with depth, ranging from 105 to 162 g/L total dissolved solids. These data fill a gap for shale-oil PW composition, the associated petroleomics plots provide a fingerprinting framework, and the results for the Permian shale-oil PW suggest that partial treatment of suspended solids and organics would support some beneficial uses such as onsite reuse and bio-energy production.

  1. Integrated Synthesis of the Permian Basin: Data and Models for Recovering Existing and Undiscovered Oil Resources from the Largest Oil-Bearing Basin in the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    John Jackson; Katherine Jackson

    2008-09-30

    Large volumes of oil and gas remain in the mature basins of North America. This is nowhere more true than in the Permian Basin of Texas and New Mexico. A critical barrier to recovery of this vast remaining resource, however, is information. Access to accurate geological data and analyses of the controls of hydrocarbon distribution is the key to the knowledge base as well as the incentives needed by oil and gas companies. The goals of this project were to collect, analyze, synthesize, and deliver to industry and the public fundamental information and data on the geology of oil and gas systems in the Permian Basin. This was accomplished in two ways. First we gathered all available data, organized it, and placed it on the web for ready access. Data include core analysis data, lists of pertinent published reports, lists of available cores, type logs, and selected PowerPoint presentations. We also created interpretive data such as type logs, geological cross sections, and geological maps and placed them in a geospatially-registered framework in ARC/GIS. Second, we created new written syntheses of selected reservoir plays in the Permian basin. Although only 8 plays were targeted for detailed analysis in the project proposal to DOE, 14 were completed. These include Ellenburger, Simpson, Montoya, Fusselman, Wristen, Thirtyone, Mississippian, Morrow, Atoka, Strawn, Canyon/Cisco, Wolfcamp, Artesia Group, and Delaware Mountain Group. These fully illustrated reports include critical summaries of published literature integrated with new unpublished research conducted during the project. As such these reports provide the most up-to-date analysis of the geological controls on reservoir development available. All reports are available for download on the project website and are also included in this final report. As stated in our proposal, technology transfer is perhaps the most important component of the project. In addition to providing direct access to data and reports through

  2. A paleoclimatic simulation of the Late Permian greenhouse world and its consequences

    Energy Technology Data Exchange (ETDEWEB)

    Moore, G.T.; Jacobson, S.R.; Hayashida, D.N. (Chevron Oil Field Research Co., La Habra, CA (United States))

    1991-03-01

    Sea-floor spreading assembled all the major cratonic blocks into a single supercontinent once in the Phanerozoic Eon. This unique Late Permian crustal tectonic event produced Pangaea and an enormous oceanic basin volume that dropped sea level to a global lowstand unrivaled in the Phanerozoic. Two paleoclimatic simulations using a numerical three-dimensional general circulation model tested changes in the greenhouse effect. The authors conclude that for a simulation to fit the Late Permian geologic record, the paleoatmosphere must contain an enhanced greenhouse gas effect. A third simulation tested changes of paleogeography in southern Pangaea (Gondwana) that did not appreciably alter the harsh continental paleoclimate. The simulated paleoclimatic changes provide extraordinarily warm ocean and atmosphere, and a significant reduction in continental rainfall and runoff. These conditions inevitably lead to more aridity and less vegetation on land, gradually reduce the delivery of vital nutrients from continental sources to marine margins, systematically liberate CO{sub 2} dissolved in ocean water, and incrementally increase stress on marine and terrestrial biotas. These consequences severely disrupted rates of oxygen and carbon cycling. Their quantitative paleoclimatic simulation is consistent with distributions of red beds, evaporites, coals, marine shelf areas, seawater isotope trends, and paleontologic originations and extinctions. Thus, the Pangaean plate assembly probably triggered an inexorable sequence of geophysical, geochemical, and biological events that forced an elevated greenhouse effect in the Late Permian, nearly annihilating the Phanerozoic biota.

  3. Repeated Carbon-Cycle Disturbances at the Permian-Triassic Boundary Separate two Mass Extinctions

    Science.gov (United States)

    Nicol, J. A.; Watson, L.; Claire, M.; Buick, R.; Catling, D. C.

    2004-12-01

    Non-marine organic matter in Permian-Triassic sediments from the Blue Mountains, eastern Australia shows seven negative δ13C excursions of up to 7%, terminating with a positive excursion of 4%. Fluctuations start at the late Permian Glossopteris floral extinction and continue until just above the palynological Permian-Triassic boundary, correlated with the peak of marine mass extinction. The isotopic fluctuations are not linked to changes in depositional setting, kerogen composition or plant community, so they evidently resulted from global perturbations in atmospheric δ13C and/or CO2. The pattern was not produced by a single catastrophe such as a meteorite impact, and carbon-cycle calculations indicate that gas release during flood-basalt volcanism was insufficient. Methane-hydrate melting can generate a single -7% shift, but cannot produce rapid multiple excursions without repeated reservoir regeneration and release. However, the data are consistent with repeated overturning of a stratified ocean, expelling toxic gases that promoted sequential mass extinctions in the terrestrial and marine realms.

  4. Permian-Triassic Tethyan realm reorganization: Implications for the outward Pangea margin

    Science.gov (United States)

    Riel, Nicolas; Jaillard, Etienne; Martelat, Jean-Emmanuel; Guillot, Stéphane; Braun, Jean

    2018-01-01

    We present a new conceptual model to explain the first order Permian-Triassic evolution of the whole > 30 000 km long Pangea margin facing the Panthalassa ocean. Compilation of available geological, geochemical, geochronogical and paleomagnetic data all along this system allowed us to distinguish three part of the margin: western Laurentia, western Gondwana and eastern Gondwana. These segments record distinct tectonic and magmatic events, which all occur synchronously along the whole margin and correlate well with the main geodynamic events of this period, i.e. subduction of the Paleotethys mid-ocean ridge at 310-280 Ma, opening of the Neotethys at 280-260 Ma, counterclockwise rotation of Pangea at 260-230 Ma and closure of the Paleotethys at 230-220 Ma. Between 260 and 230 Ma, the reorganization of the Tethyan realm triggered the up to 35° rotation of Pangea around an Euler pole located in northernmost South America. This implied both an increase and a decrease of the convergence rate between the margin and the Panthalassa ocean, north and south of the Euler pole, respectively. Thus, the Permian-Triassic Pangean margin was marked: in western Laurentia by marginal sea closure, in western Gondwana by widespread bimodal magmatic and volcanic activity, in eastern Gondwana by transpressive orogenic phase. Therefore, we propose that the Permian-Triassic evolution of the outward margin of Pangea was controlled by the Tethyan realm reorganization.

  5. Geochronologic evidence of a large magmatic province in northern Patagonia encompassing the Permian-Triassic boundary

    Science.gov (United States)

    Luppo, Tomás; López de Luchi, Mónica G.; Rapalini, Augusto E.; Martínez Dopico, Carmen I.; Fanning, Christopher M.

    2018-03-01

    The Los Menucos Complex (northern Patagonia) consists of ∼6 km thick succession of acidic and intermediate volcanic and pyroclastic products, which has been traditionally assigned to the Middle/Late Triassic. New U/Pb (SHRIMP) zircon crystallization ages of 257 ± 2 Ma at the base, 252 ± 2 Ma at an intermediate level and 248 ± 2 Ma near the top of the sequence, indicate that this volcanic event took place in about 10 Ma around the Permian-Triassic boundary. This volcanism can now be considered as the effusive terms of the neighboring and coeval La Esperanza Plutono-Volcanic Complex. This indicates that the climax of activity of a large magmatic province in northern Patagonia was coetaneous with the end-Permian mass extinctions. Likely correlation of La Esperanza- Los Menucos magmatic province with similar volcanic and plutonic rocks across other areas of northern Patagonia suggest a much larger extension than previously envisaged for this event. Its age, large volume and explosive nature suggest that the previously ignored potential role that this volcanism might have played in climatic deterioration around the Permian-Triassic boundary should be investigated.

  6. Late Permian to Triassic intraplate orogeny of the southern Tianshan and adjacent regions, NW China

    Directory of Open Access Journals (Sweden)

    Wei Ju

    2014-01-01

    Based on previous studies and recent geochronogical data, we suggest that the final collision between the Tarim Craton and the North Asian continent occurred during the late Carboniferous. Therefore, the Permian was a period of intracontinental environment in the southern Tianshan and adjacent regions. We propose that an earlier, small-scale intraplate orogenic stage occurred in late Permian to Triassic time, which was the first intraplate process in the South Tianshan Orogen and adjacent regions. The later large-scale and well-known Neogene to Quaternary intraplate orogeny was induced by the collision between the India subcontinent and the Eurasian plate. The paper presents a new evolutionary model for the South Tianshan Orogen and adjacent regions, which includes seven stages: (I late Ordovician–early Silurian opening of the South Tianshan Ocean; (II middle Silurian–middle Devonian subduction of the South Tianshan Ocean beneath an active margin of the North Asian continent; (III late Devonian–late Carboniferous closure of the South Tianshan Ocean and collision between the Kazakhstan-Yili and Tarim continental blocks; (IV early Permian post-collisional magmatism and rifting; (V late Permian–Triassic the first intraplate orogeny; (VI Jurassic–Palaeogene tectonic stagnation and (VII Neocene–Quaternary intraplate orogeny.

  7. Global nickel anomaly links Siberian Traps eruptions and the latest Permian mass extinction.

    Science.gov (United States)

    Rampino, Michael R; Rodriguez, Sedelia; Baransky, Eva; Cai, Yue

    2017-09-29

    Anomalous peaks of nickel abundance have been reported in Permian-Triassic boundary sections in China, Israel, Eastern Europe, Spitzbergen, and the Austrian Carnic Alps. New solution ICP-MS results of enhanced nickel from P-T boundary sections in Hungary, Japan, and Spiti, India suggest that the nickel anomalies at the end of the Permian were a worldwide phenomenon. We propose that the source of the nickel anomalies at the P-T boundary were Ni-rich volatiles released by the Siberian volcanism, and by coeval Ni-rich magma intrusions. The peaks in nickel abundance correlate with negative δ 13 C and δ 18 O anomalies, suggesting that explosive reactions between magma and coal during the Siberian flood-basalt eruptions released large amounts of CO 2 and CH 4 into the atmosphere, causing severe global warming and subsequent mass extinction. The nickel anomalies may provide a timeline in P-T boundary sections, and the timing of the peaks supports the Siberian Traps as a contributor to the latest Permian mass extinction.

  8. Environmental characterization of bedded salt formations and overlying areas of the Permian Basin

    International Nuclear Information System (INIS)

    1983-07-01

    This report constitutes one input to the first stage of site qualification studies. It presents a general environmental characterization of the region that is underlain by the Permian bedded salt formation. The formation covers portions of Colorado, Kansas, New Mexico, Oklahoma, and Texas. The Permian bedded salt formation is one of a number of deep, stable geologic formations being studied for potential locations for nuclear waste repositories. These studies will not necessarily lead to selection of a site. They are intended only to provide information necessary to evaluate the suitability of locations for repositories. The report is intended as a general characterization of the existing environmental setting of the Permian Region with emphasis on land, water, and air characteristics; resources; plant and animal life; and man's organizations and activities. The report provides background information about the role that this regional study will play in the overall plan for environmental impact assessments and statements deemed necessary as input to the decision-making process. Background information on the present concept of nuclear waste repository design and function is also included. The information presented in this report has been summarized from open literature readily accessible to the public. No field work was conducted nor new data used in developing the descriptions contained herein

  9. Far-travelled permian chert of the North Fork terrane, Klamath mountains, California

    Science.gov (United States)

    Mankinen, E.A.; Irwin, W.P.; Blome, C.D.

    1996-01-01

    Permian chert in the North Fork terrane and correlative rocks of the Klamath Mountains province has a remanent magnetization that is prefolding and presumably primary. Paleomagnetic results indicate that the chert formed at a paleolatitude of 8.6?? ?? 2.5?? but in which hemisphere remains uncertain. This finding requires that these rocks have undergone at least 8.6?? ?? 4.4?? of northward transport relative to Permian North America since their deposition. Paleontological evidence suggests that the Permian limestone of the Eastern Klamath terrane originated thousands of kilometers distant from North America. The limestone of the North Fork terrane may have formed at a similar or even greater distance as suggested by its faunal affinity to the Eastern Klamath terrane and more westerly position. Available evidence indicates that convergence of the North Fork and composite Central Metamorphic-Eastern Klamath terranes occurred during Triassic or Early Jurassic time and that their joining together was a Middle Jurassic event. Primary and secondary magnetizations indicate that the new composite terrane containing these and other rocks of the Western Paleozoic and Triassic belt behaved as a single rigid block that has been latitudinally concordant with the North American craton since Middle Jurassic time.

  10. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups.

    Science.gov (United States)

    Cassidy, Kira A; Mech, L David; MacNulty, Daniel R; Stahler, Daniel R; Smith, Douglas W

    2017-03-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n=534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent's size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits related

  11. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups

    Science.gov (United States)

    Cassidy, Kira A.; Mech, L. David; MacNulty, Daniel R; Stahler, Daniel R.; Smith, Douglas W.

    2017-01-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300 days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n = 534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent’s size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits

  12. 'Chasing the Dragon' - imaging of heroin inhalation leukoencephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Hagel, J. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada)]. E-mail: jeff_hagel@hotmail.com; Andrews, G. [UBC Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Vertinsky, T. [Vancouver General Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Heran, M.K.S. [Vancouver General Hospital, Div. of Neuroradiology, Vancouver, British Columbia (Canada); Keogh, C. [BC Cancer Agency, Dept. of Radiology, Vancouver, British Columbia (Canada)

    2005-10-15

    'Chasing the dragon' refers to the inhalation of heroin pyrolysate vapors produced when the freebase form of heroin is heated. Inhalation of these vapors can result in a rare toxic spongiform leukoencephalopathy. The patients may progress through 3 defined clinical stages, with one-quarter reaching the terminal stage, which invariably leads to death. Imaging and, in particular, magnetic resonance imaging (MRI) demonstrates white matter findings that are felt to be specific for this entity and essential in its early diagnosis. We present the typical imaging findings in a pictorial essay format, using images taken from 9 patients who presented within an 18-month period at UBC-affiliated hospitals. These findings include low computed tomography (CT) attenuation and high T2 MRI signal most commonly in the posterior cerebral and cerebellar white matter, cerebellar peduncles, splenium of the corpus callosum, and posterior limb of the internal capsules. In addition, there is often selective, symmetric involvement of the corticospinal tract, the medial lemniscus, and the tractus solitarius. We also present the variable diffusion-weighted imaging arid apparent diffusion coefficient findings from 4 of our patients, which to our knowledge, have not been described in the literature. (author)

  13. "Sniffer"—a novel tool for chasing vehicles and measuring traffic pollutants

    Science.gov (United States)

    Pirjola, L.; Parviainen, H.; Hussein, T.; Valli, A.; Hämeri, K.; Aaalto, P.; Virtanen, A.; Keskinen, J.; Pakkanen, T. A.; Mäkelä, T.; Hillamo, R. E.

    To measure traffic pollutants with high temporal and spatial resolution under real conditions a mobile laboratory was designed and built in Helsinki Polytechnic in close co-operation with the University of Helsinki. The equipment of the van provides gas phase measurements of CO and NO x, number size distribution measurements of fine and ultrafine particles by an electrical low pressure impactor, an ultrafine condensation particle counter and a scanning mobility particle sizer. Two inlet systems, one above the windshield and the other above the bumper, enable chasing of different type of vehicles. Also, meteorological and geographical parameters are recorded. This paper introduces the construction and technical details of the van, and presents data from the measurements performed during an LIPIKA campaign on the highway in Helsinki. Approximately 90% of the total particle number concentration was due to particles smaller than 50 nm on the highway in Helsinki. The peak concentrations exceeded often 200,000 particles cm -3 and reached sometimes a value of 10 6 cm -3. Typical size distribution of fine particles possessed bimodal structure with the modal mean diameters of 15-20 nm and ˜150 nm. Atmospheric dispersion of traffic pollutions were measured by moving away from the highway along the wind direction. At a distance of 120-140 m from the source the concentrations were diluted to one-tenth from the values at 9 m from the source.

  14. Coevolutionary arms race versus host defense chase in a tropical herbivore-plant system.

    Science.gov (United States)

    Endara, María-José; Coley, Phyllis D; Ghabash, Gabrielle; Nicholls, James A; Dexter, Kyle G; Donoso, David A; Stone, Graham N; Pennington, R Toby; Kursar, Thomas A

    2017-09-05

    Coevolutionary models suggest that herbivores drive diversification and community composition in plants. For herbivores, many questions remain regarding how plant defenses shape host choice and community structure. We addressed these questions using the tree genus Inga and its lepidopteran herbivores in the Amazon. We constructed phylogenies for both plants and insects and quantified host associations and plant defenses. We found that similarity in herbivore assemblages between Inga species was correlated with similarity in defenses. There was no correlation with phylogeny, a result consistent with our observations that the expression of defenses in Inga is independent of phylogeny. Furthermore, host defensive traits explained 40% of herbivore community similarity. Analyses at finer taxonomic scales showed that different lepidopteran clades select hosts based on different defenses, suggesting taxon-specific histories of herbivore-host plant interactions. Finally, we compared the phylogeny and defenses of Inga to phylogenies for the major lepidopteran clades. We found that closely related herbivores fed on Inga with similar defenses rather than on closely related plants. Together, these results suggest that plant defenses might be more evolutionarily labile than the herbivore traits related to host association. Hence, there is an apparent asymmetry in the evolutionary interactions between Inga and its herbivores. Although plants may evolve under selection by herbivores, we hypothesize that herbivores may not show coevolutionary adaptations, but instead "chase" hosts based on the herbivore's own traits at the time that they encounter a new host, a pattern more consistent with resource tracking than with the arms race model of coevolution.

  15. Intravenous avidin chase improved localization of radiolabeled streptavidin in intraperitoneal xenograft pretargeted with biotinylated antibody

    International Nuclear Information System (INIS)

    Zhang Meili; Sakahara, Harumi; Yao Zhengsheng; Saga, Tsuneo; Nakamoto, Yuhi; Sato, Noriko; Nakada, Hiroshi; Yamashina, Ikuo; Konishi, Junji

    1997-01-01

    In the present study, we examined the effect of avidin administered intravenously (i.v.) on the biodistribution of radiolabeled streptavidin in mice bearing intraperitoneal (IP) xenografts pretargeted with biotinylated antibody. Tumors were established in nude mice by IP inoculation of LS180 human colon cancer cells. Monoclonal antibody MLS128, which recognizes Tn antigen on mucin, was biotinylated and injected IP into the IP tumor-bearing mice. Radioiodinated streptavidin was administered IP or i.v. 48 h after pretargeting of biotinylated antibody. Avidin was administered i.v. 30 min prior to streptavidin injection. The localization of radioiodinated streptavidin in the tumor pretargeted with biotinylated antibody was significantly higher than that without pretargeting and that of radioiodinated MLS128 by the one-step method. Avidin administration significantly accelerated the clearance of radioiodinated streptavidin in blood and other normal tissues and increased the tumor-to-blood radioactivity ratio regardless of administration route of streptavidin. The i.v. avidin chase improved tumor localization of radiolabeled streptavidin in the IP xenografts pretargeted with biotinylated antibody

  16. Manufacture and test of prototype water pipe chase barrier in ITER Magnet Feeder system

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Kun, E-mail: lukun@ipp.ac.cn [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Wen, Xinjie; Liu, Chen; Song, Yuntao [Institute of Plasma Physics, Shushan Hu Road 350, Hefei, Anhui (China); Niu, Erwu [ITER China, 15B Fuxing Road, Beijing 100862 (China); Gung, Chenyu; Su, Man [ITER Organization, Route de Vinon-sur-Verdon – CS 90046, 13067 St Paul-lez-Durance Cedex (France)

    2016-11-01

    The Magnet Feeder system in the International Thermonuclear Experimental Reactor (ITER) deploys electrical currents and supercritical helium to the superconducting magnets and the magnet diagnostic signals to the operators. In the current design, the feeders located in the upper L3 level of the Tokamak gallery penetrate the Tokamak coolant water system vault, the biological shield and the cryostat. As a secondary confinement to contain the activated coolant water in the vault in the case of water pipe burst accident, a water barrier is welded between the penetration in the water pipe chase outer wall and the mid-plane of the vacuum jacket of the Feeder Coil Terminal Box (CTB). A thin-wall stainless steel diaphragm with an omega shape profile is welded around the CTB as the water barrier to endure 2 bar hydraulic pressure. In addition, the barrier is designed as a flexible compensator to withstand a maximum of 15 mm of axial displacement of the CTB in case of helium leak accident without failure. This paper presents the detail configuration, the manufacturing and assembly processes of the water barrier. Test results of the prototype water barrier under simulated accident conditions are also reported. Successful qualification of the design and manufacturing process of the water barrier lays a good foundation for the series production of this subsystem.

  17. Stratigraphy and paleogeographic significance of the Pennsylvanian-Permian Bird Spring Formation in the Ship Mountains, southeastern California

    Science.gov (United States)

    Stone, Paul; Stevens, Calvin H.; Howard, Keith A.; Hoisch, Thomas D.

    2013-01-01

    A thick sequence of limestone, dolomite, and minor sandstone assigned to the Pennsylvanian and lower Permian Bird Spring Formation is exposed in the Ship Mountains about 85 kilometers (km) southwest of Needles, California, in the eastern Mojave Desert. These strata provide a valuable reference section of the Bird Spring Formation in a region where rocks of this age are not extensively exposed. This section, which is about 900 meters (m) thick, is divided into five informal members. Strata of the Bird Spring Formation in the Ship Mountains originated as shallow-water marine deposits on the broad, southwest-trending continental shelf of western North America. Perpendicular to the shelf, the paleogeographic position of the Ship Mountains section is intermediate between those of the thicker, less terrigenous, more seaward section of the Bird Spring Formation in the Providence Mountains, 55 km to the northwest, and the thinner, more terrigenous, more landward sections of the Supai Group near Blythe, 100 km to the southeast. Parallel to the shelf, the Ship Mountains section is comparable in lithofacies and inferred paleogeographic position to sections assigned to the Callville Limestone and overlying Pakoon Limestone in northwestern Arizona and southeastern Nevada, 250 km to the northeast. Deposition of the Bird Spring Formation followed a major rise in eustatic sea level at about the Mississippian- Pennsylvanian boundary. The subsequent depositional history was controlled by episodic changes in eustatic sea level, shelf subsidence rates, and sediment supply. Subsidence rates could have been influenced by coeval continental-margin tectonism to the northwest.

  18. Stratigraphic architecture of back-filled incised-valley systems: Pennsylvanian-Permian lower Cutler beds, Utah, USA

    Science.gov (United States)

    Wakefield, Oliver J. W.; Mountney, Nigel P.

    2013-12-01

    The Pennsylvanian to Permian lower Cutler beds collectively form the lowermost stratigraphic unit of the Cutler Group in the Paradox Basin, southeast Utah. The lower Cutler beds represent a tripartite succession comprising lithofacies assemblages of aeolian, fluvial and shallow-marine origin, in near equal proportion. The succession results from a series of transgressive-regressive cycles, driven by repeated episodes of climatic variation and linked changes in relative sea-level. Relative sea-level changes created a number of incised-valleys, each forming through fluvial incision during lowered base-level. Aeolian dominance during periods of relative sea-level lowstand aids incised-valley identification as the erosive bounding surface juxtaposes incised-valley infill against stacked aeolian faces. Relative sea-level rises resulted in back-flooding of the incised-valleys and their infill via shallow-marine and estuarine processes. Back-flooded valleys generated marine embayments within which additional local accommodation was exploited. Back-filling is characterised by a distinctive suite of lithofacies arranged into a lowermost, basal fill of fluvial channel and floodplain architectural elements, passing upwards into barform elements with indicators of tidal influence, including inclined heterolithic strata and reactivation surfaces. The incised-valley fills are capped by laterally extensive and continuous marine limestone elements that record the drowning of the valleys and, ultimately, flooding and accumulation across surrounding interfluves (transgressive surface). Limestone elements are characterised by an open-marine fauna and represent the preserved expression of maximum transgression.

  19. A protorothyridid captorhinomorph reptile from the Lower Permian of Oklahoma

    National Research Council Canada - National Science Library

    Reisz, Robert R

    1980-01-01

    A new primitive captorhinomorph reptile has been found near Fort Sill, Oklahoma, in fissure fill deposits believed to be contemporaneous with the lower part of the Arroyo Formation, Clear Fork Group (Leonardian...

  20. The end-Permian regression in the western Tethys: sedimentological and geochemical evidence from offshore the Persian Gulf, Iran

    Science.gov (United States)

    Tavakoli, Vahid; Naderi-Khujin, Mehrangiz; Seyedmehdi, Zahra

    2018-04-01

    Detailed sedimentological and geochemical records across the Permian-Triassic boundary (PTB) in five offshore wells of the central Persian Gulf served to interpret the end-Permian sea-level change in this region. A decrease in sea level at the PTB was established by petrographical and geochemical study of the boundary. Thin sections showed that Upper Permian strata are composed of dolomite with minor anhydrite, changing into limestone in Lower Triassic sediments. Brine dilution toward the boundary supports sea-level fall in the Permian-Triassic transition, reflected by a decrease in anhydrite content and a shallowing-upward trend from lagoonal to peritidal facies. Isotopic changes at the boundary are in favor of sea-level fall. Changes in both carbon (from about 4 to -1‰) and oxygen (from 2 to -5‰) stable isotopes show negative excursions. The shift in carbon isotope values is a global phenomenon and is interpreted as resulting from carbonate sediment interaction with 12C-rich waters at the end-Permian sea-level fall. However, the oxygen isotope shift is attributed to the effect of meteoric waters with negative oxygen isotope values. The increase in strontium isotope ratios is also consistent with the high rate of terrestrial input at the boundary. The effect of meteoric conditions during diagenesis is evident from vuggy and moldic porosities below the PTB. The following transgression at the base of the Triassic is evident from the presence of reworked fossils and intraclasts resulting from deposition from agitated water.

  1. CONODONT BIOSTRATIGRAPHY AND LITHOSTRATIGRAPHY ACROSS THE PERMIAN-TRIASSIC BOUNDARY AT THE LUKAC SECTION IN WESTERN SLOVENIA

    Directory of Open Access Journals (Sweden)

    TEA KOLAR-JURKOVSEK

    2011-03-01

    Full Text Available Detailed conodont biostratigraphy and lithostratigraphy of the Late Permian and Early Triassic beds were studied at the LukaC section in western Slovenia. The analyzed section is composed of the Bellerophon Formation ("evaporite-dolomite member" and the newly introduced Lukaè Formation ("transitional beds", "streaky limestone member" and "carbonate-clastic beds member". The Permian-Triassic boundary interval is represented by "transitional beds" of carbonate facies deposited in shallow restricted marine conditions. The presence of H. parvus in sample L1 in the "transitional beds" marks the systemic boundary between Permian and Triassic. The studied interval is characterized by a diverse microfauna that contain conodonts, foraminifers, ostracods and gastropods. Six conodont zones have been recognized, in ascending order, the latest Changhsingian (uppermost Permian praeparvus Zone, and the Griesbachian (lowermost Triassic parvus, lobata, staeschei-isarcica, postparvus and anceps zones. This faunal succession represents the first known and the most complete conodont biozonation across the Permian-Triassic interval from the entire Dinaric region. The recognized conodont biozones can be correlated with the biozonation of the Southern Alps and of the GSSP Meishan D section. 

  2. Quantitative Measurement of GPCR Endocytosis via Pulse-Chase Covalent Labeling.

    Directory of Open Access Journals (Sweden)

    Hidetoshi Kumagai

    Full Text Available G protein-coupled receptors (GPCRs play a critical role in many physiological systems and represent one of the largest families of signal-transducing receptors. The number of GPCRs at the cell surface regulates cellular responsiveness to their cognate ligands, and the number of GPCRs, in turn, is dynamically controlled by receptor endocytosis. Recent studies have demonstrated that GPCR endocytosis, in addition to affecting receptor desensitization and resensitization, contributes to acute G protein-mediated signaling. Thus, endocytic GPCR behavior has a significant impact on various aspects of physiology. In this study, we developed a novel GPCR internalization assay to facilitate characterization of endocytic GPCR behavior. We genetically engineered chimeric GPCRs by fusing HaloTag (a catalytically inactive derivative of a bacterial hydrolase to the N-terminal end of the receptor (HT-GPCR. HaloTag has the ability to form a stable covalent bond with synthetic HaloTag ligands that contain fluorophores or a high-affinity handle (such as biotin and the HaloTag reactive linker. We selectively labeled HT-GPCRs at the cell surface with a HaloTag PEG ligand, and this pulse-chase covalent labeling allowed us to directly monitor the relative number of internalized GPCRs after agonist stimulation. Because the endocytic activities of GPCR ligands are not necessarily correlated with their agonistic activities, applying this novel methodology to orphan GPCRs, or even to already characterized GPCRs, will increase the likelihood of identifying currently unknown ligands that have been missed by conventional pharmacological assays.

  3. Visual processing in rapid-chase systems: Image processing, attention, and awareness

    Directory of Open Access Journals (Sweden)

    Thomas eSchmidt

    2011-07-01

    Full Text Available Visual stimuli can be classified so rapidly that their analysis may be based on a single sweep of feedforward processing through the visuomotor system. Behavioral criteria for feedforward processing can be evaluated in response priming tasks where speeded pointing or keypress responses are performed towards target stimuli which are preceded by prime stimuli. We apply this method to several classes of complex stimuli. 1 When participants classify natural images into animals or non-animals, the time course of their pointing responses indicates that prime and target signals remain strictly sequential throughout all processing stages, meeting stringent behavioral criteria for feedforward processing (rapid-chase criteria. 2 Such priming effects are boosted by selective visual attention for positions, shapes, and colors, in a way consistent with bottom-up enhancement of visuomotor processing, even when primes cannot be consciously identified. 3 Speeded processing of phobic images is observed in participants specifically fearful of spiders or snakes, suggesting enhancement of feedforward processing by long-term perceptual learning. 4 When the perceived brightness of primes in complex displays is altered by means of illumination or transparency illusions, priming effects in speeded keypress responses can systematically contradict subjective brightness judgments, such that one prime appears brighter than the other but activates motor responses as if it was darker. We propose that response priming captures the output of the first feedforward pass of visual signals through the visuomotor system, and that this output lacks some characteristic features of more elaborate, recurrent processing. This way, visuomotor measures may become dissociated from several aspects of conscious vision. We argue that "fast" visuomotor measures predominantly driven by feedforward processing should supplement "slow" psychophysical measures predominantly based on visual

  4. SR-71B - in Flight with F-18 Chase Aircraft - View from Air Force Tanker

    Science.gov (United States)

    1996-01-01

    NASA 831, an SR-71B operated by the Dryden Flight Research Center, Edwards, California, cruises over the Mojave Desert with an F/A-18 Hornet flying safety chase. They were photographed on a 1996 mission from an Air Force refueling tanker The F/A-18 Hornet is used primarily as a safety chase and support aircraft at Dryden. As support aircraft, the F-18s are used for safety chase, pilot proficiency and aerial photography. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and sideslip, which are normally obtained with small tubes and vanes extending into the airstream. One of Dryden's SR-71s was used

  5. Progress in the Gondwanan Carboniferous–Permian palynology ...

    Indian Academy of Sciences (India)

    palynology and correlation of the Nilawahan Group of the Salt Range, ... geological history of Pakistan both in time and space. In the time ... ern hemisphere late Palaeozoic ice age. Widespread ... time and thus demonstrated different taxa (Stephenson 2008). ... (Foster and Waterhouse 1988) and the use of the radiometric ...

  6. The Carboniferous - Permian basins of Central and Western Bohemia, the Krkonoše Mt. foreland and the Bohemian Massif, Czech Republic : part I

    Czech Academy of Sciences Publication Activity Database

    Opluštil, S.; Martínek, K.; Lojka, R.; Rosenau, N.; Zajíc, Jaroslav; Šimůnek, Z.; Drábková, J.; Štamberg, S.

    2014-01-01

    Roč. 46, č. 1 (2014), s. 14-54 ISSN 1433-1284. [Field Meeting on Carboniferous and Permian Nonmarine – Marine Correlation. Freiberg, 21.07.2014-27.07.2014] Institutional support: RVO:67985831 Keywords : Carboniferous * Permian * excursion guide Subject RIV: DB - Geology ; Mineralogy

  7. The new Permian-Triassic paleomagnetic pole for the East European Platform corrected for inclination shallowing

    Science.gov (United States)

    Fetisova, A. M.; Veselovskiy, R. V.; Scholze, F.; Balabanov, Yu. P.

    2018-01-01

    The results of detailed paleomagnetic studies in seven Upper Permian and Lower Triassic reference sections of East Europe (Middle Volga and Orenburg region) and Central Germany are presented. For each section, the coefficient of inclination shallowing f (King, 1955) is estimated by the Elongation-Inclination (E-I) method (Tauxe and Kent, 2004) and is found to vary from 0.4 to 0.9. The paleomagnetic directions, corrected for the inclination shallowing, are used to calculate the new Late Permian-Early Triassic paleomagnetic pole for the East European Platform (N = 7, PLat = 52.1°, PLong = 155.8°, A95 = 6.6°). Based on this pole, the geocentric axial dipole hypothesis close to the Paleozoic/Mesozoic boundary is tested by the single plate method. The absence of the statistically significant distinction between the obtained pole and the average Permian-Triassic (P-Tr) paleomagnetic pole of the Siberian Platform and the coeval pole of the North American Platform corrected for the opening of the Atlantic (Shatsillo et al., 2006) is interpreted by us as evidence that 250 Ma the configuration of the magnetic field of the Earth was predominantly dipolar; i.e., the contribution of nondipole components was at most 10% of the main magnetic field. In our opinion, the hypothesis of the nondipolity of the geomagnetic field at the P-Tr boundary, which has been repeatedly discussed in recent decades (Van der Voo and Torsvik, 2001; Bazhenov and Shatsillo, 2010; Veselovskiy and Pavlov, 2006), resulted from disregarding the effect of inclination shallowing in the paleomagnetic determinations from sedimentary rocks of "stable" Europe (the East European platform and West European plate).

  8. Configuration of the magnetic field and reconstruction of Pangaea in the Permian period.

    Science.gov (United States)

    Westphal, M

    1977-05-12

    The virtual geomagnetic poles of Laurasia and Gondwanaland in the Carboniferous and Permian periods diverge significantly when these continents are reassembled according to the fit calculated by Bullard et al. Two interpretations have been offered: Briden et al. explain these divergences by a magnetic field configuration very different from that of a geocentric axial dipole; Irving (and private communication), Van der Voo and French(4) suggest a different reconstruction and it is shown here that these two interpretations are not incompatible and that the first may help the second.

  9. A new tubeworm of possible serpulid affinity from the Permian of Sicily

    Directory of Open Access Journals (Sweden)

    Rossana Sanfilippo

    2016-08-01

    Full Text Available A new tubeworm, Palaeotubus sosiensis gen. et sp. nov., is described from the Permian Pietra di Salomone limestone (Sosio Valley, W Sicily. The new species is characterized by a thick tube ornamented with slightly flared peristomes and numerous longitudinal keels. The internal structure of the tube was obliterated during diagenesis, which prevents the tube unequivocal systematic attribution. Nevertheless, all preserved morphological characters strongly suggest that the new tube belongs to serpulids. When confirmed by further findings, the positive attribution of this new species to serpulids will imply that it represents the ancestor of the Serpulidae, and the earliest evidence of calcareous tubeworm polychaetes from the Palaeozoic.

  10. Sponge assemblage of some Upper Permian reef limestones from Phrae province (Northern Thailand

    Directory of Open Access Journals (Sweden)

    Baba Senowbari-Daryan

    1994-12-01

    Full Text Available The sponge fauna of uppermost Permian reef or reefal limestones of the Phrae province in northern Thailand include representatives of hexactinellida, sclerospongea,"sphinctozoans", and "inozoans". The "sphinctozoans" and "inozoans"are described in detail. Following taxa are new:"Sphinctozoans": Phraethalamia tubulara n. gen., n. sp., Ambithalamia pérmican. gen., n. sp."Inozoans": Bisiphonella tubulara n. sp., Solutossaspongia crassimuralis n.gen., n. sp.The genus name Belyaevaspongia nom. nov. is proposed for PolysiphonellaBelyaeva, 1991 (in Boiko et al., 1991, non Polysiphonella Russo, 1981.

  11. Palynology and stratigraphy preliminary study and the perforation 313/1, lower Permian. Uruguay

    International Nuclear Information System (INIS)

    Beri, A; Daners, G.; Spoturno, J.

    1998-01-01

    The palynomorphs in the bore 313/1 of the Direccion Nacional de Mineria y Geologia are analyzed. Twenty three samples were processed, and only 9 were fertile. The lithologies correspond to sandstones of variable grain size, to mudstone and to diamictite, all of them assigned to the San Gregorio and Tres Islas Fms. The most abundant genera of sporare are essentially represented by monosaccate grains. Bisaccate and striated grains are very scare. The palynoflora is comparable with those studied in Brazil in the Fm Rio Bonito. Therefore, it is proposed that the sediments studied were deposited in the early Permian. (author)

  12. Stratigraphy, structure, and lithofacies relationships of Devonian through Permian sedimentary rocks: Paradox Basin and adjacent areas - southeastern Utah. Technical report

    International Nuclear Information System (INIS)

    McCleary, J.; Rogers, T.; Ely, R.

    1983-08-01

    Geophysical well log analysis, literature review, and field work were conducted to develop isopach, structure contour, outcrop, and facies maps and cross sections for the Devonian through Permian strata of a 14,586-km 2 (5632-square-mile) area in southeastern Utah. The study area includes part of the Paradox Basin, the salt deposits of which are of interest in siting studies for a nuclear waste repository. For this reason hydrologic models of this area are needed. This study, part of which included the development of a three-dimensional stratigraphic computer model utilizing Geographic Information System software, can serve as a base for hydrologic or other models for this area. Within and adjacent to the study area, 730 wells were screened to select the 191 wells analyzed for the study. It was found that the Elbert through Molas formations did not exhibit noticeable facies changes within the study area. The Pinkerton Trail Formation exhibits moderate changes: anhydrite and shale become somewhat more abundant toward the northeast. Facies changes in the Paradox Formation are more dramatic. Thick saline facies deposits are present in the northeast, grading to thinner anhydrite and then to carbonate facies in the south and west. The lithology of the Honaker Trail Formation appears to be fairly uniform throughout the area. Facies changes in the Cutler Group are numerous and sometimes dramatic, and generally correspond to the named formations of the group. Other factors that could affect groundwater flow, such as stratigraphic cover of fine-grained rocks, area of formation outcrops, and fracturing and faulting are discussed and delineated on maps

  13. Decoding Biosynthetic Pathways in Plants by Pulse-Chase Strategies Using 13CO2 as a Universal Tracer

    Directory of Open Access Journals (Sweden)

    Adelbert Bacher

    2016-07-01

    Full Text Available 13CO2 pulse-chase experiments monitored by high-resolution NMR spectroscopy and mass spectrometry can provide 13C-isotopologue compositions in biosynthetic products. Experiments with a variety of plant species have documented that the isotopologue profiles generated with 13CO2 pulse-chase labeling are directly comparable to those that can be generated by the application of [U-13C6]glucose to aseptically growing plants. However, the application of the 13CO2 labeling technology is not subject to the experimental limitations that one has to take into account for experiments with [U-13C6]glucose and can be applied to plants growing under physiological conditions, even in the field. In practical terms, the results of biosynthetic studies with 13CO2 consist of the detection of pairs, triples and occasionally quadruples of 13C atoms that have been jointly contributed to the target metabolite, at an abundance that is well above the stochastic occurrence of such multiples. Notably, the connectivities of jointly transferred 13C multiples can have undergone modification by skeletal rearrangements that can be diagnosed from the isotopologue data. As shown by the examples presented in this review article, the approach turns out to be powerful in decoding the carbon topology of even complex biosynthetic pathways.

  14. An early bird from Gondwana: Paleomagnetism of Lower Permian lavas from northern Qiangtang (Tibet) and the geography of the Paleo-Tethys

    Science.gov (United States)

    Song, Peiping; Ding, Lin; Li, Zhenyu; Lippert, Peter C.; Yue, Yahui

    2017-10-01

    The origin of the northern Qiangtang block and its Late Paleozoic-Early Mesozoic drift history remain controversial, largely because paleomagnetic constraints from pre-Mesozoic units are sparse and of poor quality. In this paper, we provide a robust and well-dated paleomagnetic pole from the Lower Permian Kaixinling Group lavas on the northern Qiangtang block. This pole suggests that the northern Qiangtang block had a paleolatitude of 21.9 ± 4.7 °S at ca. 296.9 ± 1.9 Ma. These are the first volcanic-based paleomagnetic results from pre-Mesozoic rocks of the Qiangtang block that appear to average secular variation accurately enough to yield a well-determined paleolatitude estimate. This new pole corroborates the hypothesis, first noted on the basis of less rigorous paleomagnetic data, the presence of diamictites, detrital zircon provenance records, and faunal assemblages, that the northern Qiangtang block rifted away from Gondwana prior to the Permian. Previous studies have documented that the northern Qiangtang block accreted to the Tarim-North China continent by Norian time. We calculate a total northward drift of ca. 7000 km over ca. 100 myr, which corresponds to an average south-north plate velocities of ∼7.0 cm/yr. Our results do not support the conclusion that northern Qiangtang has a Laurasian affinity, nor that the central Qiangtang metamorphic belt is an in situ Paleo-Tethys suture. Our analysis, however, does not preclude paleogeographies that interpret the central Qiangtang metamorphic belt as an intra-Qiangtang suture that developed at southernly latitudes outboard of the Gondwanan margin. We emphasize that rigorous paleomagnetic data from Carboniferous units of northern Qiangtang and especially upper Paleozoic units from southern Qiangtang can test and further refine these paleogeographic interpretations.

  15. Uranium potential in outcropping Permian basins in France and their extensions beneath mesozoic and tertiary cover

    International Nuclear Information System (INIS)

    Hery, B.

    1990-01-01

    About a third of metropolitan France's uranium production is from Permian deposits located in the Lodeve and, to a lesser extent, Bourbon-l'Archambault basins. Of the Autun, west Vanoise, St-Affrique, Rodez, Brive and Var basins investigated in this study, only those of Rodez and Var have been shown to contain significant deposits. Some of the basins contain potentially interesting targets, often removed from the areas of known mineral occurrences, that have never been investigated. Geophysical exploration and drilling have shown that the Permian extends over a vast area beneath the cover of the large Mesozoic and Tertiary basins. However zones within reach of mineral exploration, ie. those less than 500 m deep, are only found in a few areas. To reach the distant targets down-dip in the outcropping basins or beneath the Mesozoic and Tertiary cover, a detailed study of the basin must be undertaken beforehand. To define and locate targets that are obviously more costly to investigate, direct methods of investigation need to be used such as drilling and geochemistry, and indirect methods such as remote sensing, geophysics and well-logging [fr

  16. Geochemical characteristics of the Permian sedimentary rocks from Qiangtang Basin: Constraints for paleoenvironment and paleoclimate

    Directory of Open Access Journals (Sweden)

    Junjie Hu

    2017-01-01

    Full Text Available Qiangtang Basin is expected to become important strategic petroleum exploitation area in China. However, little research has been done on the Permian strata in this area. This paper presents Lower Permian Zhanjin Formation geochemical data from the Jiaomuri area, reconstructing the paleo-depositional environment and providing information for further petroleum exploration. The geochemical characteristics of 19 samples were investigated. These geochemical samples show a developed mud flat characteristic with light rich clay content. The geological data were used to constrain the paleoredox environment, which proved that these sediments were deposited mainly beneath a slightly oxic water column with relatively low paleoproductivity as evidenced by the P/Ti (mean of 0.07 and Ba/Al (mean of 20.5. Palaeoclimate indexes such as the C-value (0.24-1.75 and Sr/Cu (1.28-11.58 reveal a humid climatic condition during Zhanjin Formation sediment deposition. The ω(LaN/ω(YbN ratio values indicate a fast sedimentary rate during the deposition period.

  17. Carbon Capture and Storage in the Permian Basin, a Regional Technology Transfer and Training Program

    Energy Technology Data Exchange (ETDEWEB)

    Rychel, Dwight [Petroleum Tech Transfer Council, Oak Hill, VA (United States)

    2013-09-30

    The Permian Basin Carbon Capture, Utilization and Storage (CCUS) Training Center was one of seven regional centers formed in 2009 under the American Recovery and Reinvestment Act of 2009 and managed by the Department of Energy. Based in the Permian Basin, it is focused on the utilization of CO2 Enhanced Oil Recovery (EOR) projects for the long term storage of CO2 while producing a domestic oil and revenue stream. It delivers training to students, oil and gas professionals, regulators, environmental and academia through a robust web site, newsletter, tech alerts, webinars, self-paced online courses, one day workshops, and two day high level forums. While course material prominently features all aspects of the capture, transportation and EOR utilization of CO2, the audience focus is represented by its high level forums where selected graduate students with an interest in CCUS interact with Industry experts and in-house workshops for the regulatory community.

  18. Regional summary and recommended study areas for the Texas Panhandle portion of the Permian Basin

    International Nuclear Information System (INIS)

    1983-12-01

    This report summarizes the regional geologic and environmental characterizations that have been completed for the Permian region of study, and describes the procedure used to identify study areas for the next phase of investigation. The factors evaluated in the Permian region fall into three broad areas: health and safety, environmental and socioeconomic, and engineering and economic considerations. Health and safety considerations included salt depth and thickness, faults, seismic activity, groundwater, salt dissolution, energy and mineral resources, presence of boreholes, and interactive land uses. Salt depth and thickness was the key health and safety factor, and when mapped, provded to be a discriminator. The evaluation of environmental and socioeconomic conditions focused primarily on the presence of urban areas and on designated land uses such as parks, wildlife areas, and historic sites. Engineering and economic considerations centered primarily on salt depth, which was already evaluated in the health and safety area. The Palo Duro and Dalhart basins are recommended for future studies on the basis of geology. In these two basins, salt depth and thickness appear promising, and there is less likelihood of past or future oil and gas exploratory holes. Environmental and socioeconomic factors did not preclude any of the basins from further study. 66 references, 16 figures, 2 tables

  19. Catastrophic dispersion of coal fly ash into oceans during the latest Permian extinction

    Energy Technology Data Exchange (ETDEWEB)

    Grasby, S.E.; Sanei, H.; Beauchamp, B. [Geological Survey Canada Calgary, Calgary, AB (Canada)

    2011-02-15

    During the latest Permian extinction about 250 Myr ago, more than 90% of marine species went extinct, and biogeochemical cycles were disrupted globally. The cause of the disruption is unclear, but a link between the eruption of the Siberian Trap flood basalts and the extinction has been suggested on the basis of the rough coincidence of the two events. The flood basalt volcanism released CO{sub 2}. In addition, related thermal metamorphism of Siberian coal measures and organic-rich shales led to the emission of methane, which would have affected global climate and carbon cycling, according to model simulations. This scenario is supported by evidence for volcanic eruptions and gas release in the Siberian Tunguska Basin, but direct indicators of coal combustion have not been detected. Here we present analyses of terrestrial carbon in marine sediments that suggest a substantial amount of char was deposited in Permian aged rocks from the Canadian High Arctic immediately before the mass extinction. Based on the geochemistry and petrology of the char, we propose that the char was derived from the combustion of Siberian coal and organic-rich sediments by flood basalts, which was then dispersed globally. The char is remarkably similar to modern coal fly ash, which can create toxic aquatic conditions when released as slurries. We therefore speculate that the global distribution of ash could have created toxic marine conditions.

  20. Geochemistry of environmentally sensitive trace elements in Permian coals from the Huainan coalfield, Anhui, China

    Science.gov (United States)

    Chen, J.; Liu, Gaisheng; Jiang, M.; Chou, C.-L.; Li, H.; Wu, B.; Zheng, Lingyun; Jiang, D.

    2011-01-01

    To study the geochemical characteristics of 11 environmentally sensitive trace elements in the coals of the Permian Period from the Huainan coalfield, Anhui province, China, borehole samples of 336 coals, two partings, and four roof and floor mudstones were collected from mineable coal seams. Major elements and selected trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and hydride generation atomic absorption spectrometry (HAAS). The depositional environment, abundances, distribution, and modes of occurrence of trace elements were investigated. Results show that clay and carbonate minerals are the principal inorganic constituents in the coals. A lower deltaic plain, where fluvial channel systems developed successively, was the likely depositional environment of the Permian coals in the Huainan coalfield. All major elements have wider variation ranges than those of Chinese coals except for Mg and Fe. The contents of Cr, Co, Ni, and Se are higher than their averages for Chinese coals and world coals. Vertical variations of trace elements in different formations are not significant except for B and Ba. Certain roof and partings are distinctly higher in trace elements than underlying coal bench samples. The modes of occurrence of trace elements vary in different coal seams as a result of different coal-forming environments. Vanadium, Cr, and Th are associated with aluminosilicate minerals, Ba with carbonate minerals, and Cu, Zn, As, Se, and Pb mainly with sulfide minerals. ?? 2011 Elsevier B.V.

  1. Permian arc evolution associated with Panthalassa subduction along the eastern margin of the South China block, based on sandstone provenance and U-Pb detrital zircon ages of the Kurosegawa belt, Southwest Japan

    Science.gov (United States)

    Hara, Hidetoshi; Hirano, Miho; Kurihara, Toshiyuki; Takahashi, Toshiro; Ueda, Hayato

    2018-01-01

    We have studied the petrography, geochemistry, and detrital zircon U-Pb ages of sandstones from shallow-marine forearc sediments, accretionary complexes (ACs), and metamorphosed accretionary complexes (Meta-ACs) within the Kurosegawa belt of Southwest Japan. Those rocks formed in a forearc region of a Permian island arc associated with subduction of the Panthalassa oceanic crust along the eastern margin of the South China block (Yangtze block). The provenance of the shallow-marine sediments was dominated by basaltic to andesitic volcanic rocks and minor granitic rocks during the late Middle to Late Permian. The ACs were derived from felsic to andesitic volcanic rocks during the Late Permian. The provenance of Meta-ACs was dominated by andesitic volcanic rocks in the Middle Permian. The provenance, source rock compositions, and zircon age distribution for the forearc sediments, ACs and Meta-ACs have allowed us to reconstruct the geological history of the Permian arc system of the Kurosegawa belt. During the Middle Permian, the ACs were accreted along the eastern margin of the South China block. The Middle Permian arc was an immature oceanic island arc consisting of andesitic volcanic rocks. During the Late Permian, the ACs formed in a mature arc, producing voluminous felsic to andesitic volcanic rocks. A forearc basin developed during the late Middle to Late Permian. Subsequently, the Middle Permian ACs and part of the Late Permian AC underwent low-grade metamorphism in the Late to Early Jurassic, presenting the Meta-ACs.

  2. Oxygenation in carbonate microbialites and associated facies after the end-Permian mass extinction: Problems and potential solutions

    Directory of Open Access Journals (Sweden)

    Stephen Kershaw

    2018-01-01

    The oxygenation state of post-end-Permian extinction shallow marine facies continues to present a challenge of interpretation, and requires high-resolution sampling and careful attention to small-scale changes, as well as loss of rock through pressure solution, as the next step to resolve the issue.

  3. Anoxia, toxic metals and acidification: volcanically-driven causes of the Middle Permian (Capitanian) mass extinction in NW Pangaea?

    Science.gov (United States)

    Bond, David; Grasby, Stephen; Wignall, Paul

    2017-04-01

    The controversial Capitanian (Middle Permian, 262 Ma) mass extinction, mostly known from equatorial latitudes, has recently been identified in a Boreal setting in Spitsbergen. We now document this extinction in the record of brachiopods from the Sverdrup Basin in NW Pangaea (Ellesmere Island, Canada), confirming Middle Permian losses as a global crisis on par with the "Big Five". Redox proxies (pyrite framboids and trace metals) show that the high latitude crisis coincided with an intensification of oxygen-poor conditions - a potent killer that is not clearly developed in lower latitude sections. Mercury becomes briefly enriched in strata at the level of the Middle Permian extinction level in Spitsbergen and Ellesmere Island, indicating voluminous but short-lived volcanism that is likely to have been the emplacement of the Emeishan large igneous province (LIP) in SW China. A potent cocktail of poisons appears to have impacted across the Boreal Realm, whilst the near-total loss of carbonates near the extinction level is also consistent with reduced pH across the region. Multiple stresses, possibly with origins in low-latitude LIP volcanism, are therefore implicated in the Middle Permian extinction and there was no respite even in the far-distant Boreal Realm.

  4. Assessment of undiscovered oil and gas resources in the Spraberry Formation of the Midland Basin, Permian Basin Province, Texas, 2017

    Science.gov (United States)

    Marra, Kristen R.; Gaswirth, Stephanie B.; Schenk, Christopher J.; Leathers-Miller, Heidi M.; Klett, Timothy R.; Mercier, Tracey J.; Le, Phuong A.; Tennyson, Marilyn E.; Finn, Thomas M.; Hawkins, Sarah J.; Brownfield, Michael E.

    2017-05-15

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean resources of 4.2 billion barrels of oil and 3.1 trillion cubic feet of gas in the Spraberry Formation of the Midland Basin, Permian Basin Province, Texas.

  5. Petroleum geological atlas of the southern permian basin area -Overview SPB-atlas project-organisation and results

    NARCIS (Netherlands)

    Doornenbal, J.C.; Abbink, O.A.; Pagnier, H.J.M.; Wees, J.D. van

    2009-01-01

    The Southern Permian Basin (also referred to as Central European Basin) is Europe s largest sedimentary basin. It is a typical intracontinental basin that evolved from latest Carboniferous to recent times and extends from eastern England to the Belarussian-Polish border and from Denmark to South

  6. The Central European Permian Basins; Rheological and structural controls on basin history and on inter-basin connectivity

    NARCIS (Netherlands)

    Smit, Jeroen; van Wees, Jan-Diederik; Cloetingh, Sierd

    2014-01-01

    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend

  7. A new morphological type of operculate microspore, Discinispora sinensis gen. nov., from the Permian petrified Noeggerathialean strobilus Discinites sinensis Wang

    Czech Academy of Sciences Publication Activity Database

    Wang, J.; Zhang, G.; Bek, Jiří; Pfefferkorn, H. W.

    2004-01-01

    Roč. 128, č. 1 (2004), s. 1-17 ISSN 0034-6667 Grant - others:Chinese National Natural Science Foundation(CN) 40102002; NIGPAS(CN) 003102; NIGPAS(CN) 023117 Institutional research plan: CEZ:AV0Z3013912 Keywords : in situ spores * Noeggerathiales * Permian Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.886, year: 2004

  8. Climatic and biotic changes around the Carboniferous/Permian boundary recorded in the continental basins of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Opluštil, S.; Šimůnek, Z.; Zajíc, Jaroslav; Mencl, V.

    2013-01-01

    Roč. 119, č. 1 (2013), s. 114-151 ISSN 0166-5162 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : biotic change * Bohemian Massif * Carboniferous-Permian transition * continental basin Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.313, year: 2013

  9. Genesis of Pb-Zn-Cu-Ag Deposits within Permian Carboniferous-Carbonate Rocks in Madina Regency, North Sumatra

    Directory of Open Access Journals (Sweden)

    Bhakti Hamonangan Harahap

    2015-09-01

    Full Text Available DOI:10.17014/ijog.2.3.167-184Strong mineralized carbonate rock-bearing Pb-Zn-Cu-Ag-(Au ores are well exposed on the Latong River area, Madina Regency, North Sumatra Province. The ore deposit is hosted within the carbonate rocks of the Permian to Carboniferous Tapanuli Group. It is mainly accumulated in hollows replacing limestone in the forms of lensoidal, colloform, veins, veinlets, cavity filling, breccia, and dissemination. The ores dominantly consist of galena (126 000 ppm Pb and sphalerite (2347 ppm Zn. The other minerals are silver, azurite, covellite, pyrite, marcasite, and chalcopyrite. This deposit was formed by at least three phases of mineralization, i.e. pyrite and then galena replaced pyrite, sphalerite replaced galena, and pyrite. The last phase is the deposition of chalcopyrite that replaced sphalerite. The Latong sulfide ore deposits posses Pb isotope ratio of 206Pb/204Pb = 19.16 - 20.72, 207Pb/204Pb = 16.16 - 17.29, and 208Pb/204Pb = 42.92 - 40.78. The characteristic feature of the deposit indicates that it is formed by a sedimentary process rather than an igneous activity in origin. This leads to an interpretation that the Latong deposit belongs to the Sedimentary Hosted Massive Sulfide (SHMS of Mississippi Valley-Type (MVT. The presence of SHMS in the island arc such as Sumatra has become controversial. For a long time, ore deposits in the Indonesian Island Arc are always identical with the porphyry and hydrothermal processes related to arc magmatism. This paper is dealing with the geology of Latong and its base metal deposits. This work is also to interpret their genesis as well as general relationship to the regional geology and tectonic setting of Sumatra.

  10. Microconchids from microbialite ecosystem immediately after end-Permian mass extinction: ecologic selectivity and implications for microbialite ecosystem structure

    Science.gov (United States)

    Yang, H.; Chen, Z.; Wang, Y. B.; Ou, W.; Liao, W.; Mei, X.

    2013-12-01

    The Permian-Triassic (P-Tr) carbonate successions are often characterized by the presence of microbialite buildups worldwide. The widespread microbialites are believed as indication of microbial proliferation immediately after the P-Tr mass extinction. The death of animals representing the primary consumer trophic structure of marine ecosystem in the P-Tr crisis allows the bloom of microbes as an important primary producer in marine trophic food web structure. Thus, the PTB microbialite builders have been regarded as disaster taxa of the P-Tr ecologic crisis. Microbialite ecosystems were suitable for most organisms to inhabit. However, increasing evidence show that microbialite dwellers are also considerably abundant and diverse, including mainly foraminifers Earlandia sp. and Rectocornuspira sp., lingulid brachiopods, ostrocods, gastropods, and microconchids. In particular, ostracods are extremely abundant in this special ecosystem. Microconchid-like calcareous tubes are also considerably abundant. Here, we have sampled systematically a PTB microbialite deposit from the Dajiang section, southern Guizhou Province, southwest China and have extracted abundant isolated specimens of calcareous worm tubes. Quantitative analysis enables to investigate stratigraphic and facies preferences of microconchids in the PTB microbialites. Our preliminary result indicates that three microconchid species Microconchus sp., Helicoconchus elongates and Microconchus aberrans inhabited in microbialite ecosystem. Most microconchilds occurred in the upper part of the microbialite buildup and the grainstone-packstone microfacies. Very few microconchilds were found in the rocks bearing well-developed microbialite structures. Their stratigraphic and environmental preferences indicate proliferation of those metazoan organisms is coupled with ebb of the microbialite development. They also proliferated in some local niches in which microbial activities were not very active even if those

  11. WILDFIRES IN THE LATE PALAEOZOIC AND MESOZOIC OF THE SOUTHERN ALPS THE LATE PERMIAN OF THE BLETTERBACH-BUTTERLOCH AREA (NORTHERN ITALY

    Directory of Open Access Journals (Sweden)

    DIETER UHL

    2012-07-01

    Full Text Available For the first time fossil macroscopic remains of charcoal as direct evidence of palaeo-wildfires from the Late Permian Gröden Formation of the Bletterbach-Butterloch area in Northern Italy is described. The charcoal consists of pycnoxylic wood and originates from gymnosperms, but a more specific affiliation is not possible due to the fragmentary nature of the material. On a global scale our knowledge about Late Permian fire-ecology is still rather scarce and this finding helps to fill one of the numerous geographical gaps in our current knowledge about Late Permian wildfires. 

  12. Pore system characteristics of the Permian transitional shale reservoir in the Lower Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    Taotao Cao

    2016-10-01

    Full Text Available The Permian shale, a set of transitional shale reservoir, is considered to be an important shale gas exploration target in the Lower Yangtze region. Due to little research conducted on the pore system characteristic and its controlling factors of the shale gas reservoir, SEM, FE-SEM, low-pressure N2 adsorption, and mercury intrusion tests were carried out on the Permian shales from the outcrop and HC well in the southern Anhui. The results show that the Permian shales mainly consist of organic matter, quartz, illite, calcite, and pyrite, of which pyrite occurs as framboids coexisting with organic matter and the organic matter is distributed in shales in stripped, interstitial, thin film and shell shapes. The basic pore types are inorganic mineral pore (intercrystalline pore, intergranular edge pore, intergranular pore, and interlayer pore in clay minerals and the organic pore and microfracture, of which organic pore and microfracture are the dominating pore types. In shale, organic pores are not developed at all in some organic grains but are well developed in others, which may be related to the types of and maceral compositions of kerogen. Under tectonic stress, shale rocks could develop mylonitization phenomenon exhibiting organic grains well blend with clay minerals, and produce a mass of microfractures and nanopores between organic matter grains and clay minerals. Mercury intrusion tests show that the shale is mainly composed of micropore and transition pore with high porosity, good pore connectivity and high efficiency of mercury withdraw, while the shale that mainly dominated by mesopore and macropore has a low porosity, poor pore connectivity, and low efficiency of the mercury withdraw. The volume percentage of mesopore and marcopore is increasing with the increase of quartz, and that of micropore and transition pore has a decreased tendency along with the increase of soluble organic matter (S1. Organic matter is the main contributor to

  13. Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

    Science.gov (United States)

    Schobben, Martin; van de Velde, Sebastiaan; Gliwa, Jana; Leda, Lucyna; Korn, Dieter; Struck, Ulrich; Vinzenz Ullmann, Clemens; Hairapetian, Vachik; Ghaderi, Abbas; Korte, Christoph; Newton, Robert J.; Poulton, Simon W.; Wignall, Paul B.

    2017-11-01

    Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian-Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-)sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the observed signal of carbon

  14. Lipid Biomarker Records Across the Permian-Triassic Boundary from Kap Stosch, Greenland

    Science.gov (United States)

    Hays, L. E.; Love, G. D.; Foster, C. B.; Grice, K.; Summons, R. E.

    2006-12-01

    The end-Permian extinction was the most severe in the past 500 million years of the Earth's history and evidence that an oceanic anoxic event (OAE) occurred contemporaneously has been presented previously [1,2]. OAEs have, therefore, been proposed as responsible for the mass mortality, and if the anoxic ocean was also euxinic, the release of hydrogen sulfide during upwelling and/or transgression provides an extinction agent in the ocean as well as on land. Chlorobiaceae, as indicators of photic zone euxinia (PZE), utilize hydrogen sulfide as an electron donor for anoxygenic photosynthesis. The detection of isorenieratane and a series of short-chain monoaromatic aryl isoprenoids, biomarkers for Chlorobiaceae, in sediments indicates the presence of hydrogen sulfide in the photic zone of the water column during sediment deposition. The Kap Stosch area in Eastern Greenland was identified as a Permian-Triassic boundary (PTB) outcrop of homogeneous shale, silty shale, and siltstone facies [3]. Another late Permian section in Eastern Greenland, the Ravnefjeld Formation, has framboidal pyrites indicative of sulfidic deep water [4]. A sample suite from the Kap Stosch region was studied using standard organic geochemistry methods including stable isotopic analyses of organic carbon, Rock-Eval pyrolysis, and biomarker hydrocarbon analysis. Aryl isoprenoids, including isorenieratane, were present in all samples studied and the concentrations were observed to fluctuate in tandem with TOC, similar to other Mesozoic OAEs. The molecular ratios of pristane/phytane and hopanes/steranes as well as the 2-methyl-hopane index (2-MHI) fluctuated dramatically through this section as they do at the type section at Meishan and in the Perth Basin [5]. The 2-MHI shows an inverse pattern to the total aryl isoprenoids, perhaps indicative of instability in the form of primary productivity in the water column during euxinic episodes. This can result in nitrogen limitation and a competitive

  15. Rare earths from uranium mineralization occurrences in the Permian of the Gemericum, the Western Carpathians

    International Nuclear Information System (INIS)

    Rojkovic, I.; Medved, J.; Walzel, E.; Posta, S.; Sulovsky, P.

    1989-01-01

    Uranium mineralization in the Permian of the Gemericium is accompanied by apatite, monazite and xenotime. The study of rare earth elements distribution is based on the results of instrumental neutron activation analysis and optical emission spectroscopy analysis of rocks and energy-dispersive X-ray microanalyses of minerals. The main light rare earth elements bearing mineral is monazite; for heavy rare earth elements it is xenotime. The rocks accompanying uranium mineralization have increased rare earth elements contents. The mobilization and concentration of uranium mineralization took place during the Alpine metallogenic processes. These processes were also associated with rare earth elements mobilization is which total and selective enrichment in light rare earth elements and heavy rare earth elements was observed. (author). 12 figs., 6 tabs., 5 refs

  16. Origin and distribution of tonsteins in late permian coal seams of Southwestern China

    Science.gov (United States)

    Zhou, Yinzhu; Ren, Y.-L.; Bohor, B.F.

    1982-01-01

    We have surveyed the areal and stratigraphic distribution of tonsteins in Late Permian coalfields of southwestern China over an area of several hundred thousand square kilometers. We studied the relationship between tonstein distribution and sedimentary environment. Based on mineralogical and petrographic data, we have concluded that these tonsteins originated as air-fall volcanic ashes. Following accumulation in the peat swamps, in situ alteration of the vitric and lithic components took place under acidic conditions, leading to the formation of kaolinite. Based on petrologic, mineralogic, and chemical analytical data, we have determined that the application of mineralogic and geochemical criteria for tonsteins may be useful in correlating coal beds, predicting coal qualities and reconstructing related sedimentary paleoenvironmental conditions. ?? 1982.

  17. Lithofacies palaeogeography of the Late Permian Wujiaping Age in the Middle and Upper Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    Jin-Xiong Luo

    2014-10-01

    Full Text Available The lithofacies palaeogeography of the Late Permian Wujiaping Age in Middle and Upper Yangtze Region was studied based on petrography and the “single factor analysis and multifactor comprehensive mapping” method. The Upper Permian Wujiaping Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks and clastic rocks, with lesser amounts of siliceous rocks, pyroclastic rocks, volcanic rocks and coal. The rocks can be divided into three types, including clastic rock, clastic rock–limestone and limestone–siliceous rock, and four fundamental ecological types and four fossil assemblages are recognized in the Wujiaping Stage. Based on a petrological and palaeoecological study, six single factors were selected, namely, thickness (m, content (% of marine rocks, content (% of shallow water carbonate rocks, content (% of biograins with limemud, content (% of thin-bedded siliceous rocks and content (% of deep water sedimentary rocks. Six single factors maps of the Wujiaping Stage and one lithofacies palaeogeography map of the Wujiaping Age were composed. Palaeogeographic units from west to east include an eroded area, an alluvial plain, a clastic rock platform, a carbonate rock platform where biocrowds developed, a slope and a basin. In addition, a clastic rock platform exists in the southeast of the study area. Hydrocarbon source rock and reservoir conditions were preliminarily analyzed based on lithofacies palaeogeography. Sedimentary environments have obvious controls over the development of the resource rocks. With regard to the abundance of organic matter, the hydrocarbon potential of the coastal swamp environment is the best, followed by the basin environment and the carbonate rock platform. The gas reservoir types of the Wujiaping Stage can be classified as conventional and unconventional gas reservoirs, like coal bed gas and shale gas; all of them have well exploration prospects.

  18. Ca and Sr isotope records support ocean acidification during end-Permian mass extinction

    Science.gov (United States)

    Wang, J.; Jacobson, A. D.; Zhang, H.; Ramezani, J.; Sageman, B. B.; Hurtgen, M.; Bowring, S. A.; Shen, S.

    2017-12-01

    The end-Permian mass extinction represents the most devastating loss of biodiversity during the Phanerozoic. A negative carbon isotope (δ13C) excursion that accompanies the event suggests a significant perturbation to the global carbon cycle, likely induced by CO2 emissions during eruption of the Siberian Traps large igneous province. The carbon cycle is linked with the Ca and Sr cycles through chemical weathering and carbonate precipitation. Therefore, analyses of Ca (δ44/40Ca), radiogenic Sr (87Sr/86Sr), and stable Sr (δ88/86Sr) isotope abundance variations in marine carbonate rocks spanning the Permian-Triassic Boundary (PTB) can reveal key information about biogeochemical changes that occurred during this time. We report δ44/40Ca, 87Sr/86Sr, and δ88/86Sr records analyzed by TIMS for the Meishan and Dajiang sections in China. δ44/40Ca values exhibit similar patterns in both sections. The values remain unchanged across the extinction event layer (EXT) and then decrease by 0.20‰ before increasing by 0.20‰ to 0.40‰ around the PTB. In the Meishan section, 87Sr/86Sr ratios increase after the EXT and return to pre-excursion levels by the PTB. Simultaneously, δ88/86Sr values decrease by 0.12‰ across the EXT and increase by 0.08‰ by the PTB. The patterns of our data support the hypothesis that elevated atmospheric CO2 levels enhanced chemical weathering inputs and might have caused transient ocean acidification, with an "alkalinity overshoot" and increased carbonate deposition occurring after the extinction. Additional measurements and model calculations are underway to help refine and improve these preliminary interpretations.

  19. Geochemical Identification of Windblown Dust Deposits in the Upper Permian Brushy Canyon Formation, Southern New Mexico

    Science.gov (United States)

    Tice, M. M.; Motanated, K.; Weiss, R.

    2009-12-01

    Windblown dust is a potentially important but difficult-to-quantify source of siliciclastics for sedimentary basins worldwide. Positively identifying windblown deposits requires distinguishing them from other low density suspension transport deposits. For instance, laminated very fine grained sandstones and siltstones of the Upper Permian Brushy Canyon Formation have been variously interpreted as 1) the deposits of slow-moving, low-density turbidity currents, 2) distal overbank deposits of turbidity currents, 3) the deposits of turbulent suspensions transported across a pycnocline (interflows), and 4) windblown dust. This facies forms the bulk of Brushy Canyon Formation slope deposits, so understanding its origin is critical to understanding the evolution of the basin as a whole. We use a geochemical mapping technique (x-ray fluorescence microscopy) to show that these rocks are up to two times enriched in very fine sand sized zircon and rutile grains relative to Bouma A divisions of interbedded turbidites, suggesting substantial turbulence during transport. However, in contrast with the A divisions, the laminated sandstones and siltstones never show evidence of scour or amalgamation, implying that flow turbulence did not interact with underlying beds. Moreover, proximal loess deposits are often characterized by elevated Zr/Al2O3. These observations are most consistent with windblown interpretations for Brushy Canyon Formation slope sediments, and suggest that evolution of this early deepwater slope system was controlled largely by short-distance aeolian transport of very fine sand and silt from the coast. Heavy mineral incorporation into Brushy Canyon Formation slope deposits as reflected in laminae-scale bulk Zr and Ti abundances may preserve a long-term record of local wind intensity during the Upper Permian.

  20. Permian depositional age of metaturbidites of the Duque de York Complex, southern Chile: U-Pb SHRIMP data and palynology

    International Nuclear Information System (INIS)

    Sepulveda, Fernando A; Palma-Heldt, Sylvia; Herve, Francisco; Fanning, Mark

    2010-01-01

    The Duque de York Complex (DYC) is part of the low grade metamorphic accretionary complexes of the pre-Andean Patagonian 'basement'. It is a sedimentary succession exposed along the western margin of southernmost South America. New U-Pb zircon ages and palynological data restrict the maximum depositional age of the DYC to the limit between the early Permian (Kungurian) and the middle Permian (Roadian). The palynological association recorded in the DYC, characterized mainly by Gymnospermopsida pollen, indicates a humid environment of forest with an under-growth of ferns. Regional paleogeographic correlations point out that an interpretation of DYC as an autochthonous terrane cannot be discarded, contrasting with previous hypotheses which suggest an allochthonous character for this complex

  1. Significance of detrital zircons in upper Devonian ocean-basin strata of the Sonora allochthon and Lower Permian synorogenic strata of the Mina Mexico foredeep, central Sonora, Mexico

    Science.gov (United States)

    Poole, F.G.; Gehrels, G.E.; Stewart, John H.

    2008-01-01

    U-Pb isotopic dating of detrital zircons from a conglomeratic barite sandstone in the Sonora allochthon and a calciclastic sandstone in the Mina Mexico foredeep of the Minas de Barita area reveals two main age groups in the Upper Devonian part of the Los Pozos Formation, 1.73-1.65 Ga and 1.44-1.42 Ga; and three main age groups in the Lower Permian part of the Mina Mexico Formation, 1.93-1.91 Ga, 1.45-1.42 Ga, and 1.1-1.0 Ga. Small numbers of zircons with ages of 2.72-2.65 Ga, 1.30-1.24 Ga, ca. 2.46 Ga, ca. 1.83 Ga, and ca. 0.53 Ga are also present in the Los Pozos sandstone. Detrital zircons ranging in age from 1.73 to 1.65 Ga are considered to have been derived from the Yavapai, Mojave, and Mazatzal Provinces and their transition zones of the southwestern United States and northwestern Mexico. The 1.45-1.30 Ga detrital zircons were probably derived from scattered granite bodies within the Mojave and Mazatzal basement rocks in the southwestern United States and northwestern Mexico, and possibly from the Southern and Eastern Granite-Rhyolite Provinces of the southern United States. The 1.24-1.0 Ga detrital zircons are believed to have been derived from the Grenville (Llano) Province to the east and northeast or from Grenvilleage intrusions or anatectites to the north. Several detrital zircon ages ranging from 2.72 to 1.91 Ga were probably derived originally from the Archean Wyoming Province and Early Paleoproterozoic rocks of the Lake Superior region. These older detrital zircons most likely have been recycled one or more times into the Paleozoic sandstones of central Sonora. The 0.53 Ga zircon is believed to have been derived from a Lower Cambrian granitoid or meta-morphic rock northeast of central Sonora, possibly in New Mexico and Colorado, or Oklahoma. Detrital zircon geochronology suggests that most of the detritus in both samples was derived from Laurentia to the north, whereas some detritus in the Permian synorogenic foredeep sequence was derived from the

  2. Temperature profiles from expendable bathythermograph (XBT) casts from the USCGC CHASE in the North Atlantic Ocean in support of the Integrated Global Ocean Services System (IGOSS) from 1974-02-26 to 1974-03-01 (NODC Accession 7400264)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — XBT data were collected from the USCGC CHASE in support of the Integrated Global Ocean Services System (IGOSS). Data were collected by the US Coast Guard from 26...

  3. Paleoecological and paleoenvironmental changes during the continental Middle-Late Permian transition at the SE Iberian Ranges, Spain

    Science.gov (United States)

    De la Horra, R.; Galán-Abellán, A. B.; López-Gómez, J.; Sheldon, N. D.; Barrenechea, J. F.; Luque, F. J.; Arche, A.; Benito, M. I.

    2012-08-01

    The Middle and Late Permian are characterized by a pair of mass-extinction events that are recorded in both marine and continental environments. Here, we present the first continental western peri-Tethyan record of an extinction event located in the Middle-Late interval. In the SE Iberian Ranges, Central Spain, the transition between the Lower and Middle subunits of the Middle Permian Alcotas Formation indicates a significant paleoclimatic change from arid and semiarid conditions towards more humid conditions. Coincident with the onset of humid conditions there were changes in the sedimentology, mineralogy, and geochemistry that indicate significant environmental changes including a shift in weathering intensity and a change of fluvial style from braided to meandering systems. Near the top of the Middle Subunit, a local biotic crisis is recorded by palynomorph assemblages. Following this crisis, there is a total absence of coal beds, plant remains, and microflora that defines a barren zone in the uppermost part of the Alcotas Formation which is recorded throughout the basin. The barren zone is accompanied by a shift back to braided stream systems, but not by a return to carbonate-bearing paleosols indicative of arid or semi-arid conditions. This combination of features is consistent with other Middle-Late continental basins related with mass extinctions, so the barren zone is interpreted as the extinction interval. The regional character of the extinction interval and its proximity with the Middle-Late Permian transition could be related with the global mid-Capitanian biotic turnover described in this period of time in other marine basins. However, the common difficulties of dating with precision non-marine rocks make this relationship difficult to probe in the Iberian Basin and in other Middle-Late Permian basins. Further work, including high resolution carbon-isotope analyses and complete studies of the magnetostratigraphy, should be desirable in order to obtain

  4. Lithostratigraphy, depositional environments and sedimentology of the Permian Vryheid Formation (Karoo Supergroup), Arnot North, Witbank Coalfield, South Africa

    OpenAIRE

    2009-01-01

    M.Sc. This work documents the lithostratigraphy and interpreted depositional environments of the Permian Vryheid Formation in the most northern proximal setting yet studied in the Witbank Coalfield. Data from 924 boreholes from two mining companies (Anglo Operations Ltd. and Xstrata Coal Ltd.) drilled over 50 years, covering an area of 910km2 revealed a 35m sequence of terrigenous clastic sedimentary rocks containing two coal seams. These seams are numbered No. 1 at the base and No. 2 at t...

  5. Identification of the Early Permian (Autunian) in the subsurface of the Ebro Basin, NE Spain, and its paleogeographic consequences

    OpenAIRE

    Arche, A.; Díez, J.B.; López-Gómez, José

    2007-01-01

    [EN] The Early Permian (Autunian) has not been identifi ed up to now in the subsurface of the Tertiary Ebro Basin because of the scarcity of oil well boreholes reaching the Variscan basement and the systematic attribution of a Carboniferous age, without any paleontological data, to the unmetamorfosed siliciclastic sediments found at the base of some of them, clearly above the Early Paleozoic basement. Grey and black shale samples recovered from cores preserved in the REPSOL-YPF archi...

  6. Delayed recovery of non-marine tetrapods after the end-Permian mass extinction tracks global carbon cycle

    OpenAIRE

    Irmis, Randall B.; Whiteside, Jessica H.

    2011-01-01

    During the end-Permian mass extinction, marine ecosystems suffered a major drop in diversity, which was maintained throughout the Early Triassic until delayed recovery during the Middle Triassic. This depressed diversity in the Early Triassic correlates with multiple major perturbations to the global carbon cycle, interpreted as either intrinsic ecosystem or external palaeoenvironmental effects. In contrast, the terrestrial record of extinction and recovery is less clear; the effects and magn...

  7. Multiple episodes of extensive marine anoxia linked to global warming and continental weathering following the latest Permian mass extinction.

    Science.gov (United States)

    Zhang, Feifei; Romaniello, Stephen J; Algeo, Thomas J; Lau, Kimberly V; Clapham, Matthew E; Richoz, Sylvain; Herrmann, Achim D; Smith, Harrison; Horacek, Micha; Anbar, Ariel D

    2018-04-01

    Explaining the ~5-million-year delay in marine biotic recovery following the latest Permian mass extinction, the largest biotic crisis of the Phanerozoic, is a fundamental challenge for both geological and biological sciences. Ocean redox perturbations may have played a critical role in this delayed recovery. However, the lack of quantitative constraints on the details of Early Triassic oceanic anoxia (for example, time, duration, and extent) leaves the links between oceanic conditions and the delayed biotic recovery ambiguous. We report high-resolution U-isotope (δ 238 U) data from carbonates of the uppermost Permian to lowermost Middle Triassic Zal section (Iran) to characterize the timing and global extent of ocean redox variation during the Early Triassic. Our δ 238 U record reveals multiple negative shifts during the Early Triassic. Isotope mass-balance modeling suggests that the global area of anoxic seafloor expanded substantially in the Early Triassic, peaking during the latest Permian to mid-Griesbachian, the late Griesbachian to mid-Dienerian, the Smithian-Spathian transition, and the Early/Middle Triassic transition. Comparisons of the U-, C-, and Sr-isotope records with a modeled seawater PO 4 3- concentration curve for the Early Triassic suggest that elevated marine productivity and enhanced oceanic stratification were likely the immediate causes of expanded oceanic anoxia. The patterns of redox variation documented by the U-isotope record show a good first-order correspondence to peaks in ammonoid extinctions during the Early Triassic. Our results indicate that multiple oscillations in oceanic anoxia modulated the recovery of marine ecosystems following the latest Permian mass extinction.

  8. Identificação de Paspalum notatum fluegge e Axonopus affinis chase através da análise de fragmentos foliares Identification of Paspalum notatum fluegge and Axonopus affinis chase through leaf fragments analysis

    Directory of Open Access Journals (Sweden)

    Maria Cláudia Lopes Nogueira

    1999-03-01

    Full Text Available Este trabalho teve como objetivo a caracterização e identificação de fragmentos foliares de Paspalum notatum Fluegge e Axonopus affinis Chase, como forma de subsidiar projetos de avaliação da dieta de animais fistulados. Para a caracterização das espécies, foram feitas várias coletas de folhas em áreas de pastagem natural do Campus da Universidade Federal de Santa Maria (RS, de maio de 1992 a junho de 1993. A diferenciação das espécies foi baseada no padrão de nervação, presença de pêlos e características do ápice e bordo foliar, observadas com auxílio de estereomicroscópio. A habilidade de um observador em identificar fragmentos das duas espécies numa mistura e a eficácia dos descritores foliares mencionados foram testadas através de análise estatística. Desta forma, foi constatado que o padrão de nervação é o melhor critério de diferenciação e que A. affinis difere de P. notatum, basicamente, pelo ápice foliar obtuso e pela presença de nervuras quaternárias. A análise estatística confirmou a capacidade do observador em reconhecer fragmentos das duas espécies.This research aimed at the characterization and identification of leaves, fragments of Paspalum notatum Fluegge and Axonopus affinis Chase, for future studies of diet evaluation of fistuleted animals. For the species characterization, several collections of leaves were made in native pasture areas at the UFSM Campus (Santa Maria, RS from May, 1992 to June, 1993. The differentiation of the species was based on the leave’s venation pattern, hair presence, leaf border and apex features, observed with a stereomicroscope. The obverver’s ability to identify the two species of leaves in a misture were tested with statistical analysis. It was observed that the venation pattern is the best characterization criteria and that A. affinis differs from P. notatum mainly by the obtuse leaf apex and by the quaternary vein presence. The statistical analysis

  9. Tectono-sedimentary evolution of the Permian-Triassic extension event in the Zagros basin (Iran): results from analogue modelling

    Science.gov (United States)

    Madani-kivi, M.; Zulauf, G.

    2015-12-01

    Since the 1970s, the largest oil and gas reservoirs have been discovered in the Permian-Early Triassic formationsin Saudi Arabia. Thus, this time period is important for the discovery of new oil reserves in Iran. The Arabian passivecontinental margin has undergone lithospheric extension during the Permian-Triassic, which led to the formation of theNeo-Tethys. The aim of this paper is to describe the development of the continental rift basin in the Zagros region basedon the tectono-sedimentological evolution. We have studied well-log data to specify the distribution of synrift depositsin the Zagros and have related this information to the modelling. Environmental changes indicated by various sedimentarysequences, from a siliciclastic basin to a carbonate platform setting, are described. The Cambrian Hormuz salt, whichoverlies the metamorphosed Precambrian basement, becomes effective as a basal detachment layer influencing the styleof overburden deformation during the Permian-Triassic extension event. We have investigated the formation of variousstructures linked to the presence or absence of the Hormuz layer by analogue modelling and relating these structures to theLate Palaeozoic sedimentation. Based on results of the analogue modelling, we argue that the basal detachment layer (Hormuzseries) has contributed to the various structural styles of the extensional basin development in the Fars domain and theLorestan domain.

  10. Permian-Triassic thermal anomaly of the active margin of South America as a result of plate kinematics reorganization

    Science.gov (United States)

    Riel, Nicolas; Jaillard, Etienne; Guillot, Stéphane; Martelat, Jean-Emmanuel; Braun, Jean

    2013-04-01

    From Permian to Triassic times, tectonic plate reorganization provoked Pangaea breakup, counterclockwise rotation of Gondwana, closing of the Paleo-Tethys Ocean and opening of the Neo-Tethys oceanic realm. Meanwhile, the switch from arc volcanism to widespread S-type magmatism along the western South American active margin around 275-265 Ma is symptomatic of the onset of a large-scale Permian-Triassic thermal anomaly (PTTA)affecting the whole margin. Here we report metamorphic and U-Pb geochronological results from the El Oro metamorphic complex in the forearc zone of southwestern Ecuador, which recorded the last step, at 230-225 Ma, of the PTTA. The change in the drift direction of Gondwana from north to east at ca. 270 Ma was related to plate reorganization and provoked the verticalization of the subducted Panthalassa slab. As the slab verticalized, strong heat advection produced a high heat flow beneath the active margin inducing the development of a huge thermal anomaly responsible for the PTTA, which lasted 30 Ma. This voluminous magmatic activity culminated at the Permian-Triassic boundary, and may have contributed to the degradation of life conditions on the Earth surface.

  11. Aridification across the Carboniferous-Permian transition in central equatorial Pangea: The Catalan Pyrenean succession (NE Iberian Peninsula)

    Science.gov (United States)

    Mujal, Eudald; Fortuny, Josep; Marmi, Josep; Dinarès-Turell, Jaume; Bolet, Arnau; Oms, Oriol

    2018-01-01

    The Carboniferous-Permian terrestrial successions record a global climatic shift from icehouse to hothouse conditions. Our multidisciplinary study documents an aridification trend throughout the 1000 m thick composite terrestrial succession of the western Catalan Pyrenees (NE Iberian Peninsula), representing this time period. The detailed stratigraphic framework integrates sedimentology, paleopedology, biochronology (plant fossils and tetrapod footprints) and geochronology (paleomagnetism). Additional absolute age correlation is also carried out. The new and reviewed data show that the late Carboniferous wet environments (with short drought periods) progressively changed to a strong seasonal semi-arid and arid climate (with short humid periods) through the early Permian. This paleoclimatic trend supports the previously suggested aridification of the Pangean pan-tropical belt, and supports the hypothesis of the influence of the recurrent climatic fluctuations in Central Pangea, being tentatively correlated to the Southern Gondwanan glaciation-deglaciation periods. Therefore, the Carboniferous-Permian terrestrial succession from the Catalan Pyrenees emerges as a continuous record that can help to constrain late Paleozoic paleoenvironmental events.

  12. Timing of global regression and microbial bloom linked with the Permian-Triassic boundary mass extinction: implications for driving mechanisms.

    Science.gov (United States)

    Baresel, Björn; Bucher, Hugo; Bagherpour, Borhan; Brosse, Morgane; Guodun, Kuang; Schaltegger, Urs

    2017-03-06

    New high-resolution U-Pb dates indicate a duration of 89 ± 38 kyr for the Permian hiatus and of 14 ± 57 kyr for the overlying Triassic microbial limestone in shallow water settings of the Nanpanjiang Basin, South China. The age and duration of the hiatus coincides with the Permian-Triassic boundary (PTB) and the extinction interval in the Meishan Global Stratotype Section and Point, and strongly supports a glacio-eustatic regression, which best explains the genesis of the worldwide hiatus straddling the PTB in shallow water records. In adjacent deep marine troughs, rates of sediment accumulation display a six-fold decrease across the PTB compatible with a dryer and cooler climate as indicated by terrestrial plants. Our model of the Permian-Triassic boundary mass extinction (PTBME) hinges on the synchronicity of the hiatus with the onset of the Siberian Traps volcanism. This early eruptive phase released sulfur-rich volatiles into the stratosphere, thus simultaneously eliciting a short-lived ice age responsible for the global regression and a brief but intense acidification. Abrupt cooling, shrunk habitats on shelves and acidification may all have synergistically triggered the PTBME. Subsequently, the build-up of volcanic CO 2 induced a transient cool climate whose early phase saw the deposition of the microbial limestone.

  13. Mineralogical and Geochemical Characteristics of Late Permian Coals from the Mahe Mine, Zhaotong Coalfield, Northeastern Yunnan, China

    Directory of Open Access Journals (Sweden)

    Xibo Wang

    2015-07-01

    Full Text Available This paper reports the mineralogical and geochemical compositions of the Late Permian C2, C5a, C5b, C6a, and C6b semianthracite coals from the Mahe mine, northeastern Yunnan, China. Minerals in the coals are mainly made up of quartz, chamosite, kaolinite, mixed-layer illite/smectite (I/S, pyrite, and calcite; followed by anatase, dolomite, siderite, illite and marcasite. Similar to the Late Permian coals from eastern Yunnan, the authigenic quartz and chamosite were precipitated from the weathering solution of Emeishan basalt, while kaolinite and mixed-layer I/S occurring as lenses or thin beds were related to the weathering residual detrital of Emeishan basalt. However, the euhedral quartz and apatite particles in the Mahe coals were attributed to silicic-rock detrital input. It further indicates that there has been silicic igneous eruption in the northeastern Yunnan. Due to the silicic rock detrital input, the Eu/Eu* value of the Mahe coals is lower than that of the Late Permian coals from eastern Yunnan, where the detrital particles were mainly derived from the basalt. The high contents of Sc, V, Cr, Co, Ni, Cu, Ga, and Sn in the Mahe coals were mainly derived from the Kangdian Upland.

  14. Initiation of simian virus 40 DNA replication in vitro: Pulse-chase experiments identify the first labeled species as topologically unwound

    International Nuclear Information System (INIS)

    Bullock, P.A.; Seo, Yeon Soo; Hurwitz, J.

    1989-01-01

    A distinct unwound form of DNA containing the simian virus 40 (SV40) origin is produced in replication reactions carried out in mixtures containing crude fractions prepared from HeLa cells. This species, termed form U R , comigrates on chloroquine-containing agarose gels with the upper part of the previously described heterogeneous highly unwound circular DNA, form U. As with form U, formation of form U R is dependent upon the SV40 tumor (T) antigen. Pulse-chase experiments demonstrate that the first species to incorporate labeled deoxyribonucleotides comigrates with form U R . Restriction analyses of the products of the pulse-chase experiments show that initiation occurs at the SV40 origin and then proceeds outward in a bidirectional manner. These experiments establish form U R as the earliest detectable substrate for SV40 DNA replication and suggest that SV40 DNA replication initiates on an unwound species

  15. Permian-Triassic boundary microbialites at Zuodeng Section, Guangxi Province, South China: Geobiology and palaeoceanographic implications

    Science.gov (United States)

    Fang, Yuheng; Chen, Zhong-Qiang; Kershaw, Stephen; Yang, Hao; Luo, Mao

    2017-05-01

    A previously unknown microbialite bed in the Permian-Triassic (P-Tr) boundary beds of Zuodeng section, Tiandong County, Guangxi, South China comprises a thin (5 cm maximum thickness) stromatolite in the lower part and the remaining 6 m is thrombolite. The Zuodeng microbialite has a pronounced irregular contact between the latest Permian bioclastic limestone and microbialite, as in other sites in the region. The stromatolite comprises low-relief columnar and broad domal geometries, containing faint laminations. The thrombolite displays an irregular mixture of sparitic dark coloured altered microbial fabric and light coloured interstitial sediment in polished blocks. Abundant microproblematic calcimicrobe structures identified here as Gakhumella are preserved in dark coloured laminated areas of the stromatolite and sparitic areas in thrombolites (i.e. the calcimicrobial part, not the interstitial sediment) and are orientated perpendicular to stromatolitic laminae. Each Gakhumella individual has densely arranged segments, which form a column- to fan-shaped structure. Single segments are arch-shaped and form a thin chamber between segments. Gakhumella individuals in the stromatolite and thrombolite are slightly different from each other, but are readily distinguished from the Gakhumella- and Renalcis-like fossils reported from other P-Tr boundary microbialites in having a smaller size, unbranching columns and densely arranged, arch-shaped segments. Renalcids usually possess a larger body size and branching, lobate outlines. Filament sheath aggregates are also observed in the stromatolite and they are all orientated in one direction. Both Gakhumella and filament sheath aggregates may be photosynthetic algae, which may have played an important role in constructing the Zuodeng microbialites. Other calcimicrobes in the Zuodeng microbialite are spheroids, of which a total of five morphological types are recognized from both stromatolite and thrombolite: (1) sparry calcite

  16. Late Early Permian continental ichnofauna from Lake Kemp, north-central Texas, USA

    Science.gov (United States)

    Lucas, S.G.; Voigt, S.; Lerner, A.J.; Nelson, W.J.

    2011-01-01

    Continental trace fossils of Early Permian age are well known in the western United States from Wolfcampian (~. Asselian to Artinskian) strata, but few examples are known from Leonardian (~. Kungurian) deposits. A substantial ichnofauna from strata of the lower part of the Clear Fork Formation at Lake Kemp, Baylor County, Texas, augments the meager North American record of Leonardian continental trace fossil assemblages. Ichnofossils at Lake Kemp occur in the informally-named Craddock dolomite member of the Clear Fork Formation, which is 12-15. m above the local base of the Clear Fork. The trace-bearing stratum is an up-to-0.3. m thick, laminated to flaser-bedded, dolomitic siltstone that also contains mud cracks, raindrop impressions, microbially induced mat structures, and some land-plant impressions. We interpret the Craddock dolomite member as the feather-edge of a marine transgressive carbonate deposit of an irregular coastline marked by shallow bays or estuaries on the eastern shelf of the Midland basin, and the trace-fossil-bearing stratum at Lake Kemp is an unchannelized flow deposit on a muddy coastal plain. The fossil site at Lake Kemp yields a low to moderately diverse fauna of invertebrate and vertebrate traces. A sparse invertebrate ichnofauna consists of arthropod feeding and locomotion traces assigned to Walpia cf. W. hermitensis White, 1929 and Diplichnites gouldi Gevers in Gevers et al., 1971. Tetrapod footprints are most common and assigned to Batrachichnus salamandroides (Geinitz, 1861), cf. Amphisauropus kablikae (Geinitz and Deichm??ller, 1882), and Dromopus lacertoides (Geinitz, 1861), which represent small temnospondyl, seymouriamorph, and basal sauropsid trackmakers. Both the traces and sedimentary features of the fossil horizon indicate a freshwater setting at the time of track formation, and the trace assemblage represents the Scoyenia ichnofacies and the Batrachichnus ichnofacies in an overbank environment with sheet flooding and shallow

  17. Biolaminoid facies in a peritidal sabkha: Permian Platy Dolomite of northern Poland

    Science.gov (United States)

    Brehm, Ulrike; Gasiewicz, Andreij; Gerdes, Giesela; Krumbein, Wolfgang

    The Platy Dolomite, a carbonate unit in the Zechstein Formation (Upper Permian) of the Leba Elevation, Poland, was deposited in a semi-closed or completely separated back-barrier sabkha environment. This arid, hypersaline zone is comparable to the recent Gavish Sabkha, Sinai. The processes which formed the modern Gavish Sabkha are similar to those responsible for the biolaminoid formation in the Platy Dolomite series. The deposition of this Platy Dolomite was mainly the result of microbial activity building extensive microbial mats. The Platy Dolomite is characterized by loosely packed microbial biolaminoids (a less significantly laminated build-up of biogenetic sediments) with horizontally or obliquely to vertically orientated filaments. Intermediary coated grains occur. Densely packed, flat laminated stromatolitic rocks, pure oolites, and bioclastic sedimentary strata are rarely intercalated with the biolaminoid beds. Laboratory and field investigations indicate that carbonate formation was induced by the chemoorganotrophic bacterial decay of cyanobacterial mats. Magnesium was bound and absorbed by organic matter and later liberated by anaerobic decay. Early diagenetic processes formed Mg2+- and Ca2+-enriched solutions in which carbonates precipitated biologically and chemically. A system of biogenic carbonate formation of the Platy Dolomite microbiolite series is proposed and supported by the results of microbiological laboratory studies.

  18. Architecture and quantitative assessment of channeled clastic deposits, Shihezi sandstone (Lower Permian, Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Chengye Jia

    2017-02-01

    Full Text Available Lower Permian Shihezi sandstone in Ordos Basin is the largest gas reservoir in China. Architecture elements of channel, overbank and floodplain facies of braided channel deposits were identified through an outcrops survey, and their proportion of channel facies have been quantitatively estimated from well logging. Characteristics of architecture elements, such as sand thickness, bounding surfaces and lithofacies were investigated through outcrops and core. Petrology of Shihezi sandstone has also been studied in detail. Analysis on sandstone components shows that monocrystalline quartz with approximately 76% bulk volume, and lithic up to 5%–45% bulk volume, are the two main components. Litharenite and lithic quartz sandstone are the main rock types. Compaction is concluded by former researchers as the control factor of low permeability. Examination through thin section reveals that secondary pores developed well in coarse sand. Inter-granular dissolution is included as the positive effect to increasing porosity, and is concluded as the control factor to the generation of net pay. Scale of coarse grained channel fills and channel bar sandstone bodies are quantitatively estimated. Strike-oriented, dip-oriented, and vertical distribution of channel fills and channel bar sandstone bodies have been investigated. The geometry of sand bodies can be depicted as an elongated lens. Subsurface mapping reveals that channel sandstone bodies distribute widely from both lateral and longitudinal cross section profiles, and are poorly connected.

  19. Ocean Acidification and the End-Permian Mass Extinction: To What Extent does Evidence Support Hypothesis?

    Directory of Open Access Journals (Sweden)

    Marie-Béatrice Forel

    2012-09-01

    Full Text Available Ocean acidification in modern oceans is linked to rapid increase in atmospheric CO2, raising concern about marine diversity, food security and ecosystem services. Proxy evidence for acidification during past crises may help predict future change, but three issues limit confidence of comparisons between modern and ancient ocean acidification, illustrated from the end-Permian extinction, 252 million years ago: (1 problems with evidence for ocean acidification preserved in sedimentary rocks, where proposed marine dissolution surfaces may be subaerial. Sedimentary evidence that the extinction was partly due to ocean acidification is therefore inconclusive; (2 Fossils of marine animals potentially affected by ocean acidification are imperfect records of past conditions; selective extinction of hypercalcifying organisms is uncertain evidence for acidification; (3 The current high rates of acidification may not reflect past rates, which cannot be measured directly, and whose temporal resolution decreases in older rocks. Thus large increases in CO2 in the past may have occurred over a long enough time to have allowed assimilation into the oceans, and acidification may not have stressed ocean biota to the present extent. Although we acknowledge the very likely occurrence of past ocean acidification, obtaining support presents a continuing challenge for the Earth science community.

  20. The genesis and isotopic composition of carbonates associated with some Permian Australian coals

    International Nuclear Information System (INIS)

    Gould, K.W.; Smith, J.W.

    1979-01-01

    Siderite and calcite are the two forms of carbonate commonly associated with Permian Australian coals. The former occurs as disseminated spherulites and is a product of the early post-depositional environment. Isotopic measurements show that the CO 2 fixed as siderite did not result from the direct oxidation of photosynthetically derived materials, but rather from the anaerobic fermentation of these. The higher concentrations of calcite are generally found towards the roofs of coal seams and are characterized by isotopic enrichments to delta 13 C values of +25% PDB. Isotopic exchange between CO 2 and CH 4 within the coal seam is postulated as the mechanism which leads to the formation of isotopically heavy CO 2 . At sites along the seam margins where the CO 2 escapes, interaction with circulating metal ions or preexisting calcite results in the deposition of ''heavy'' calcite. With increasing alteration of coal by thermal metamorphism, the 13 C content of calcites and finally siderites decreases so that it more nearly approaches that of the associated coal. (Auth.)

  1. Radiosensitivity of subterranean bacteria in the Hungarian upper permian siltstone formation

    International Nuclear Information System (INIS)

    Farkas, G.; Gazso, L.G.; Diosi, G.

    2002-01-01

    The main purpose of this work was to study the radioresistance of subterranean aerobic and anaerobic isolates from the Hungarian Upper Permian Siltstone (Aleurolite) Formation, in order to assess the safety of potential sites of future underground repositories for nuclear waste. A total of 93 isolates were studied. The radiosensitivities of these aerobic and anaerobic bacteria isolates were determined: the D 10 values (decimal reducing doses) of the aerobic spore-formers lay in the range 0.80-2.44 kGy, and those of the anaerobic spore-formers lay in the range 1.86-4.93 kGy. The D 10 values of the aerobic and anaerobic vegetative isolates were much lower, in the ranges 0.11-0.57 and 0.22-0.40 kGy, respectively. The variability in bacterial radioresistance indicates the biodiversity at this potential disposal site. These results can affect the construction of a future underground repository, since knowledge of the most resistant microorganism may be of importance as concerns calculation of the time required to inactivate the bacteria surrounding the containers

  2. Thermal properties of Permian Basin evaporites to 493 K temperature and 30 MPa confining pressure

    International Nuclear Information System (INIS)

    Durham, W.B.; Heard, H.C.; Boro, C.O.; Keller, K.T.; Ralph, W.E.; Trimmer, D.A.

    1987-03-01

    Laboratory measurements of the thermal conductivity and diffusivity of four rock salts, two anhydrites, and two dolomites bordering Cycle 4 and Cycle 5 bedded salt formations in the Permian Basin in Deaf Smith County, Texas, were made in conditions ranging from 303 to 473 K in temperature and 0.1 to 31.0 MPa in hydrostatic confining pressure. Within the +-5% measurement resolution neither conductivity nor diffusivity showed a dependence upon pressure in any of the rocks. Conductivity and diffusivity in all rocks had a negative temperature dependence. For the Cycle 4 salt samples, conductivity fell from 5.5 to 3.75 W/m . K, and diffusivity fell from about 2.7 to 1.7 x 10 -6 m 2 /s. One Cycle 5 salt was a single crystal with anomalous results, but the other had a low conductivity with very weak temperature dependence and a high diffusivity. In the nonsalts, conductivity and diffusivity decreased 10 to 20% over the temperature range explored. In measurements of the coefficient of thermal linear expansion for Cycle 5 salt and nonsalts, the coefficient typically varied from about 12 x 10 -6 K -1 at P = 3.0 MPa to 4 x 10 -6 K -1 at P = 30 MPa for both nonsalt rocks. In anhydrite, it decreased with increasing temperature. In dolomite, the coefficient increased at roughly the same rate. Expansion of the salt ranged from 33 to 38 x 10 -6 K -1 and was independent of pressure and temperature

  3. Body size reductions in nonmammalian eutheriodont therapsids (Synapsida) during the end-Permian mass extinction.

    Science.gov (United States)

    Huttenlocker, Adam K

    2014-01-01

    The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the 'Lilliput effect,' a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts) using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion) models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma) consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1) active, directional evolution in size traits is rare over macroevolutionary time scales and 2) geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns.

  4. Thermal conductivity and diffusivity of Permian Basin bedded salt at elevated pressure and temperature

    International Nuclear Information System (INIS)

    Durham, W.B.; Boro, C.O.; Beiriger, J.M.; Montan, D.N.

    1983-10-01

    Measurements of thermal conductivity and diffusivity were made on five core samples of bedded rock salt from the Permian Basin in Texas to determine its suitability as an underground nuclear waste repository. The sample size was 100 mm in diameter by 250 mm in length. Measurements were conducted under confining pressures ranging from 3.8 to 31.0 MPa and temperatures from room temperature to 473 K. Conductivity showed no dependence on confining pressure but evidenced a monotonic, negative temperature dependence. Four of the five samples showed conductivities clustered in a range of 5.6 +- 0.5 W/m.K at room temperature, falling to 3.6 +- 0.3 W/m.K at 473 K. These values are approximately 20% below those for pure halite, reflecting perhaps the 5 to 20%-nonhalite component of the samples. Diffusivity also showed a monotonic, negative temperature dependence, with four of the five samples clustered in a range of 2.7 +- 0.4 x 10 -6 m 2 /s at room temperature, and 1.5 +- 0.3 x 10 -6 m 2 /s at 473 K, all roughly 33% below the values for pure halite. One sample showed an unusually high conductivity (it also had the highest diffusivity), about 20% higher than the others; and one sample showed an unusually low diffusivity (it also had the lowest conductivity), roughly a factor of 2 lower than the others. 27 references, 8 figures, 4 tables

  5. δ 13C evidence that high primary productivity delayed recovery from end-Permian mass extinction

    Science.gov (United States)

    Meyer, K. M.; Yu, M.; Jost, A. B.; Kelley, B. M.; Payne, J. L.

    2011-02-01

    Euxinia was widespread during and after the end-Permian mass extinction and is commonly cited as an explanation for delayed biotic recovery during Early Triassic time. This anoxic, sulfidic episode has been ascribed to both low- and high-productivity states in the marine water column, leaving the causes of euxinia and the mechanisms underlying delayed recovery poorly understood. Here we use isotopic analysis to examine the changing chemical structure of the water column through the recovery interval and thereby better constrain paleoproductivity. The δ 13C of limestones from 5 stratigraphic sections in south China displays a negative gradient of approximately 4‰ from shallow-to-deep water facies within the Lower Triassic. This intense gradient declines within Spathian and lowermost Middle Triassic strata, coincident with accelerated biotic recovery and carbon cycle stabilization. Model simulations show that high nutrient levels and a vigorous biological pump are required to sustain such a large gradient in δ 13C, indicating that Early Triassic ocean anoxia and delayed recovery of benthic animal ecosystems resulted from too much productivity rather than too little.

  6. New absolute paleointensity determinations for the Permian-Triassic boundary from the Kuznetsk Trap Basalts.

    Science.gov (United States)

    Kulakov, E.; Metelkin, D. V.; Kazansky, A.

    2015-12-01

    We report the results of a pilot absolute paleointensity study of the ~250 Ma basalts of Kuznetsk traps (Kuznetsk Basin, Altai-Sayan folded area). Studied samples are characterized by a reversed polarity of natural remanent magnetization that corresponds to the lower part of Siberian Trap basalts sequence. Geochemical similarity of Kuznets basalts with those from Norilsk region supports this interpretation. Primary origin of thermal remanence in our sample is confirmed by a positive backed contact test. Rock magnetic analyses indicate that the ChRM is carried by single-domain titanomagnetite. The Coe-version of the Thellier-Therllier double-heating method was utilized for the paleointensity determinations. In contrast to the previous studies of the Permian-Triassic Siberian trap basalts, our data indicate that by the P-T boundary the paleofield intensity was relatively high and comparable with geomagnetic field strength for the last 10 millions of years. New results question the duration of the "Mesozoic dipole-low".

  7. Isotope shifts in the late Permian of the Delaware Basin, Texas, precisely timed by varved sediments

    International Nuclear Information System (INIS)

    Magaritz, M.; Oregon Univ., Eugene; Anderson, R.Y.; Holser, W.T.; Saltzmann, E.S.; Garber, J.

    1983-01-01

    Closely spaced samples (285 in number) of varved sediments from the Upper Permian in Delaware Basin, Texas, have been analyzed for delta 13 Csub(carb), delta 13 Csub(org), delta 18 Osub(carb), Csub(org), Csub(carb) and calcite/dolomite. delta 13 C records a dramatic rise from -2.8 to + 5.7per mille in only 4400 years, detected in three sections across the basin, extrapolating smoothly through a 600-year interruption by a local (west side of the basin) fresh-water inflow evidenced by low delta 18 O. This continuity and low Csub(org) within the basin, both indicate that the excess net deposition of Csub(org), necessary to generate the rise in delta 13 C, took place in the ocean external to the Delaware Basin, Correlation with similar records from the Zechstein Basin suggest that the event was world-wide, although this poses obvious difficulties for the carbon cycle. The rate of rise of delta 13 C, and its sustained high level, must imply conversions of oxidized carbon to reduced carbon that are very large depending on which reservoirs were involved. (orig.)

  8. Analysis of cyclical sedimentation in the lower Permian Mchuchuma coalfield (South-West-Tanzania)

    Energy Technology Data Exchange (ETDEWEB)

    Casshyap, S M; Kreuser, T; Wopfner, H

    1987-01-01

    A statistical approach by a modified Markov process model was used to prove that the lower Permian coal measures of the Tanzanian Mchuchuma basin developed distinct cyclicities during deposition. From results the transition path of lithologic states typical for this coal sequence is as follows: (A) coarse sandstone, (B) medium sandstone, (C) fine-very fine sandstone, (D) shale, (E) mudstone, (F) coal or (E+F) and again (A) coarse sandstone. The majority of cycles is asymmetric (ABCDEF-ABC..) but symmetrical cycles are present as well (ABCDEFED). The statistical results concur with observed sedimentological evidence of depositional environment. Fining upward cycles correspond to the development of basal channel bars, changing into levees, then into back swamps which are topped by coal swamps. Frequent interbedding of coal and mudstone in the upper part of the coal measures calls for periodic flooding and flushing of fine clastics into coal-forming swamps causing interruption of peat formation. Cyclical deposition is explained by wandering channels in response to varying discharge and rate of deposition, their lateral frequent shifting caused the formation of asymmetrical cycles in this fluviodeltaic depositional model. 33 refs., 7 figs., 1 tab.

  9. Thermomechanical analyses of conceptual repository designs for the Paradox and Permian Basins

    International Nuclear Information System (INIS)

    Loken, M.C.; Callahan, G.D.; Svalstad, D.K.; Wagner, R.A.

    1987-11-01

    The potential repositories are designed to accommodate all waste forms emplaced at various thermal loadings; specifically, commercial high-level waste (30 W/m 2 ), spent fuel (15 W/m 2 ), defense high-level waste (20 W/m 2 ), and remote-handled and contact-handled transuranic nonheat-generating waste. The study evaluates the design parameters, primarily thermal loading, based on a comparison of calculable thermomechanical parameters with prescribed performance constraints. This evaluation was accomplished by numerical simulation using finite element techniques of the canister, disposal room, and repository regions of each potential site. Important thermal and thermomechanical results were compared with their prescribed constraint or limit value. All of the performance constraints were satisfied at the Davis Canyon site in the Paradox Basin for commercial high-level waste, spent fuel, and defense high-level waste at areal thermal loadings of 20 W/m 2 , 15 W/m 2 , and 20 W/m 2 , respectively. Similarly, for the Deaf Smith County site in the Permian Basin, commercial high-level waste, spent fuel, and defense high-level waste thermal loadings of 13.5 W/m 2 , 8.5 W/m 2 , and 6.0 W/m 2 , respectively, satisfied all of the performance constraints. 89 refs., 64 figs., 22 tabs

  10. Chasing the Mirage: a grounded theory of the clinical reasoning processes that Registered Nurses use to recognize delirium.

    Science.gov (United States)

    El Hussein, Mohamed; Hirst, Sandra

    2016-02-01

    The aim of this study was to construct a grounded theory that explains the clinical reasoning processes that registered nurses use to recognize delirium in older adults in acute care hospitals. Delirium is under-recognized in acute hospital settings, this may stem from underdeveloped clinical reasoning processes. Little is known about registered nurses' (RNs) clinical reasoning processes in complex situations such as delirium recognition. A grounded theory approach was used to analyse interview data about the clinical reasoning processes of RNs in acute hospital settings. Seventeen RNs were recruited. Concurrent data collection and comparative analysis and theoretical sampling were conducted in 2013-2014. The core category to emerge from the data was 'chasing the mirage', which describes RNs' clinical reasoning processes to recognize delirium during their interaction with older adults. Understanding the reasoning that contributes to delirium under-recognition provides a strategy by which, this problem can be brought to the forefront of RNs' awareness and intervention. Delirium recognition will contribute to quality care for older adults. © 2015 John Wiley & Sons Ltd.

  11. Costs of locomotion in polar bears: when do the costs outweigh the benefits of chasing down terrestrial prey?

    Science.gov (United States)

    Gormezano, Linda J; McWilliams, Scott R; Iles, David T; Rockwell, Robert F

    2016-01-01

    Trade-offs between locomotory costs and foraging gains are key elements in determining constraints on predator-prey interactions. One intriguing example involves polar bears pursuing snow geese on land. As climate change forces polar bears to spend more time ashore, they may need to expend more energy to obtain land-based food. Given that polar bears are inefficient at terrestrial locomotion, any extra energy expended to pursue prey could negatively impact survival. However, polar bears have been regularly observed engaging in long pursuits of geese and other land animals, and the energetic worth of such behaviour has been repeatedly questioned. We use data-driven energetic models to examine how energy expenditures vary across polar bear mass and speed. For the first time, we show that polar bears in the 125-235 kg size range can profitably pursue geese, especially at slower speeds. We caution, however, that heat build-up may be the ultimate limiting factor in terrestrial chases, especially for larger bears, and this limit would be reached more quickly with warmer environmental temperatures.

  12. Pteridophytes from Lower Gondwana formations of the Ib River Coalfield, Orissa and their diversity and distribution in the Permian of India

    Energy Technology Data Exchange (ETDEWEB)

    Goswami, S.; Singh, K.J.; Chandra, S. [Fakir Mohan University, Balasore (India). PG Dept. of Environmental Science

    2006-12-15

    Recent extensive investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified numerous fossiliferous beds in the lower Gondwana deposits. Six exposures of the Barakar and lower Kamthi formations yielded diverse and abundant plant remains. The flora includes twenty-three genera representing nine groups viz., Lycopodiales, Equisetales, Sphenophyllales, Filicales, Cordaitales, Coniferales, Ginkgoales, Cycadales and Glossopteridales. Systematic descriptions of the pteridophyte taxa namely Cyclodendron (Lycopodiales), Schizoneura, Raniganjia, Bengalia, equisetaceous stems (Equisetales), Trizygia, Benlightfootia (Sphenophyllales), Neomariopteris, and Dichotomopteris (Filicales) are presented in this paper. Pteridophytic leaves comprising nine taxa viz., Cyclodendron leslii, Schizoneura gondwanensis, Raniganjia bengalensis, Bengalia raniganjensis, Trizygia speciosa, Benlightfootia indica, Neomariopteris hughesii, N. talchirensis, and Dichotomopteris sp. together with equisetaceous stems constitute about 7.88% (72 specimens) of the total plant assemblage collected from this coalfield. Among the pteridophytes, equisetaceous stems are most abundant (40.3%; 29 specimens) followed by Schizoneura gondwanensis (20.8%, 15 specimens) and Trizygia speciosa (13.9%, 10 specimens). A summary of the known diversity of pteridophytes in the Indian Permian as a whole is provided.

  13. The Relationship Between Intracranial Pressure and Age-Chasing Age-Related Reference Values

    DEFF Research Database (Denmark)

    Pedersen, Sarah Hornshøj; Lilja-Cyron, Alexander; Andresen, Morten

    2018-01-01

    Background: No true reference values for intracranial pressure (ICP) in humans exist; current values are estimated from measurements in adults who undergo treatment in order to correct ICP. We report ICP values in a "pseudonormal" group of children and adults to examine if age affects ICP. Method...

  14. Sr-Nd-Pb isotope systematics of the Permian volcanic rocks in the northern margin of the Alxa Block (the Shalazhashan Belt) and comparisons with the nearby regions: Implications for a Permian rift setting?

    Science.gov (United States)

    Shi, Guanzhong; Wang, Hua; Liu, Entao; Huang, Chuanyan; Zhao, Jianxin; Song, Guangzeng; Liang, Chao

    2018-04-01

    The petrogenesis of the Permian magmatic rocks in the Shalazhashan Belt is helpful for us to understand the tectonic evolution of the Central Asian Orogenic Belt (CAOB) in the northern margin of the Alxa Block. The Permian volcanic rocks in the Shalazhashan Belt include basalts, trachyandesites and trachydacites. Our study shows that two basalt samples have negative εNd(t) values (-5.4 to -1.5) and higher radiogenic Pb values, which are relevant to the ancient subcontinental lithospheric mantle. One basalt sample has positive εNd(t) value (+10) representing mafic juvenile crust and is derived from depleted asthenosphere. The trachyandesites are dated at 284 ± 3 Ma with εNd(t) = +2.7 to +8.0; ISr = 0.7052 to 0.7057, and they are generated by different degrees of mixing between mafic magmas and crustal melts. The trachydacites have high εNd(t) values and slightly higher ISr contents, suggesting the derivation from juvenile sources with crustal contamination. The isotopic comparisons of the Permian magmatic rocks of the Shalazhashan Belt, the Nuru-Langshan Belt (representing the northern margin of the Alxa Block), the Solonker Belt (Mandula area) and the northern margin of the North China Craton (Bayan Obo area) indicate that the radiogenic isotopic compositions have an increasingly evolved trend from the south (the northern margins of the Alxa Block and the North China Craton) to the north (the Shalazhashan Belt and the Solonker Belt). Three end-member components are involved to generate the Permian magmatic rocks: the ancient subcontinental lithospheric mantle, the mafic juvenile crust or newly underplated mafic rocks that were originated from depleted asthenosphere, and the ancient crust. The rocks correlative with the mafic juvenile crust or newly underplated mafic rocks are predominantly distributed along the Shalazhashan Belt and the Solonker Belt, and the rocks derived from ancient, enriched subcontinental lithospheric mantle are mainly distributed along

  15. Depositional setting, petrology and chemistry of Permian coals from the Parana Basin: 2. South Santa Catarina Coalfield, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Kalkreuth, W.; Mexias, A.; Balbinot, M.; Levandowski, J. [Instituto de Geociencias, UFRGS, Porto Alegre (Brazil); Holz, M. [Inst. de Geociencias, UFBA, Salvador, Bahia (Brazil); Willett, J.; Finkelman, R. [U.S. Geological Survey, Reston, VA (United States); Burger, H. [Freie Universitaet Berlin, Geoinformatik, (Germany)

    2010-12-01

    In Brazil economically important coal deposits occur in the southern part of the Parana Basin, where coal seams occur in the Permian Rio Bonito Formation, with major coal development in the states of Rio Grande de Sul and Santa Catarina. The current paper presents results on sequence stratigraphic interpretation of the coal-bearing strata, and petrological and geochemical coal seam characterization from the South Santa Catarina Coalfield, Parana Basin. In terms of sequence stratigraphic interpretation the precursor mires of the Santa Catarina coal seams formed in an estuarine-barrier shoreface depositional environment, with major peat accumulation in a high stand systems tract (Pre-Bonito and Bonito seams), a lowstand systems tract (Ponta Alta seam, seam A, seam B) and a transgressive systems tract (Irapua, Barro Branco and Treviso seams). Seam thicknesses range from 1.70 to 2.39 m, but high proportions of impure coal (coaly shale and shaley coal), carbonaceous shale and partings reduce the net coal thickness significantly. Coal lithoypes are variable, with banded coal predominant in the Barro Branco seam, and banded dull and dull coal predominantly in Bonito and Irapua seams, respectively. Results from petrographic analyses indicate a vitrinite reflectance range from 0.76 to 1.63 %Rrandom (HVB A to LVB coal). Maceral group distribution varies significantly, with the Barro Branco seam having the highest vitrinite content (mean 67.5 vol%), whereas the Irapua seam has the highest inertinite content (33.8 vol%). Liptinite mean values range from 7.8 vol% (Barro Branco seam) to 22.5 vol% (Irapua seam). Results from proximate analyses indicate for the three seams high ash yields (50.2 - 64.2 wt.%). Considering the International Classification of in-Seam Coals, all samples are in fact classified as carbonaceous rocks (> 50 wt.% ash). Sulfur contents range from 3.4 to 7.7 wt.%, of which the major part occurs as pyritic sulfur. Results of X-ray diffraction indicate the

  16. Natural gas qualities in the Southern Permian basin; Die Erdgasqualitaeten im suedlichen Permbecken

    Energy Technology Data Exchange (ETDEWEB)

    Gerling, P.; Kockel, F. [BGR, Hannover (Germany); Lokhorst, A.; Geluk, M.C. [TNO, Haarlem (Netherlands); Nicholson, R.A. [British Geological Survey, Nottingham (United Kingdom); Laier, T. [Danmarks og Groenlands Geologiske Undersoegelse, Kopenhagen (Denmark); Pokorski, J. [Panstwowy Instytut Geologiczny, Warsaw (Poland)

    1998-12-31

    There is a substantial amount of molecular and isotopic gas data in the literature but mostly in the archives of companies and geological services. As the geological services of most European countries traditionally contain (confidential and non-confidential) data on geology and resources these institutions from Great Britain, the Netherlands, Denmark, Poland and Germany decided to compile molecular and isotopic natural gas data from the area of the Southern European Permian basin. The partially EU-subsidised project was carried out between 1994 and 1997 (LOKHORST ed. 1998) The atlas is based on existing data and also on newly determined molecular and isotopic gas parameters. Ring analyses of national and international standard gases ensure the quality and comparability of the data thus obtained. The aim of the ``stocktaking`` of natural gas was to describe the gas qualities from the Southern North Sea in the West to the Eastern borders of Poland, to characterise them genetically and to relate the to the geological environment. (orig.) [Deutsch] Ein substantieller Anteil von molekularen und isotopischen Gasdaten existiert, teilweise in der Literatur, vor allem aber in den Archiven der Firmen und der geologischen Dienste. Da die geologischen Dienste der meisten europaeischen Laender traditionell (oeffentliche und vertrauliche) Daten ueber die Geologie und Rohstoffe vorhalten, haben sich diese Institutionen aus Grossbritanien, den Niederlanden, Daenemark, Polen und Deutschlands entschlossen, molekulare und isotopische Erdgasdaten aus dem Bereich des suedlichen europaeischen Permbeckens zu kompilieren. Das partiell von der EU gefoerderte Projekt wurde in den Jahren 1994 bis 1997 durchgefuehrt (LOKHORST ed. 1998). Ausser auf bereits vorhandenen Daten beruht der Atlas auf etwa 200 Neu-Bestimmungen molekularer und isotopischer Gasparameter. Ringanalysen nationaler und internationeler Standardgase gewaehrleisteten die Qualitaet und die Vergleichbarkeit der gewonnenen

  17. Formation of phreatomagmatic pipes in the Tunguska Basin (Siberia, Russia) during the end-Permian

    Science.gov (United States)

    Polozov, Alexander; Svensen, Henrik; Planke, Sverre

    2010-05-01

    We recently proposed that numerous pipes piercing sedimentary rocks of Tunguska Basin triggered the Permian-Triassic mass extinction (Svensen et al., 2009). Large amounts of greenhouse and poisonous gases were released through the pipes and into P-Tr atmosphere, partly formed by heating of petroleum-bearing evaporites. The sub-volcanic part of the Siberian Traps was emplaced in the Tunguska Basin sedimentary sequences, which includes Pre-Cambrian source rocks, Early Cambrian evaporites, and Paleozoic terrigenous and coal-bearing rocks. Spectacular breccia pipes are numerous in the evaporate-parts of the basin, and are filled with volcaniclastic rocks and commercial magnetite mineralization. Although these pipes have been intensively studied in order to understand the iron ore formation, the origin and formation of the pipes is poorly understood. Many researchers emphasize that magma-sediments interaction as a key reason of pipe formation, whereas phreatomagmatic hypothesis are also proposed. In order to improve the understanding of pipe formation and ore-deposition, we have studied a basalt-rich breccia pipe piercing Cambrian evaporates at the Nepa locality in East Siberia. Textural features of the volcanic fragments in the breccias include lapilli, Pele's hear, glassy basalt and dolerite clasts, blocks of tuffs in addition to sedimentary rocks. Calcite and halite are the most common types of cement. We have studied minerals from the breccia cement and from reaction rims around clasts in order to understand the hydrothermal system that developed after the pipe formed. Calcite and dolomite are the dominating carbonates, and two types of anhydrite is present. Biotite, Cl-Fe-bearing amphibole (hastingsite), and Cl-F-apatite are amongst early hydrothermal minerals covering magmatic clast and lapillies. Our new data confirm (i) the phreatomagmatic nature of breccia filling in the Tunguska Basin pipes and (ii) the key role of sedimentary brine and petroleum involved in

  18. Lithofacies palaeogeography of the Upper Permian Changxing Stage in the Middle and Upper Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    He Youbin

    2013-04-01

    Full Text Available Based on the petrological study, according to single factor analysis and multifactor comprehensive mapping method, the quantitative lithofacies palaeogeography of the Upper Permian Changxing Stage of the Middle and Upper Yangtze Region was studied. The Changxing Stage in the Middle and Upper Yangtze Region is mainly composed of carbonate rocks; in addition, clastic and siliceous rocks occur with rare coals and pyroclastic rocks. Lithofacies can be divided into five types, including clastic rock assemblage, clastic rock–limestone assemblage, limestone assemblage, limestone–siliceous rock assemblage, and siliceous rock–clastic rock assemblage. Four fundamental ecological types and five fossil assemblages were recognized in the Changxing Stage. On the basis of the petrological and palaeoecological study, eight single factors were chosen including thickness, content of marine rocks, content of shallow water carbonate rocks, content of bioclasts with limemud matrix, content of bioclasts with sparry cement, distribution of reefs, content of thin bedded siliceous rocks and content of deep water sedimentary rocks. And eight single factor maps and one lithofacies paleogeographic map of the Changxing Stage were compiled. Paleoenvironments from west to east include an erosional area, fluvial plain, clastic platform, carbonate platform and reefs that developed there, slope and basin, low energy organic banks, and high energy organic banks. Sedimentary environments have an obvious control on the development of the source rocks, and the excellent source rocks are developed in the Dalong Formation. Changxing Stage reservoirs should be dominated by the reef and platform surrounding the Guangyuan–Liangping Basin rim area, and is the most favorable exploration area of the reef petroleum reservoirs of the Changxing Formation.

  19. Revision of the Late Permian Non-Marine Bivalve Genus Verneuilunio Starobogatov, 1987

    Directory of Open Access Journals (Sweden)

    M.N. Urazaeva

    2015-03-01

    Full Text Available The genus Verneuilunio (type species Naiadites verneuili has been singled out from the genus Palaeanodonta Amalitzky based on differences in the structure of hinge margin established using the literature data. Both genera have been included in the family Palaeanodontidae, which used to be considered by the discoverer of this genus as a subjective synonym for the family Palaeomutelidae. The revision of W. Amalitskii’s collection has demonstrated that the original diagnosis of the genus con-tains a number of inaccuracies. This creates difficulties for identification of the genus Verneuilunio and complicates its placement within higher taxa. The paper presents a revised diagnosis of the genus Verneuilunio. The detailed description of its type species is provided. The genus Verneuilunio has been assigned to the family Naiaditidae based on the duplivincular and slightly amphidetic ligament. According to this feature, the genus under study is significantly different from other unio-like Late Permian non-marine bivalve genera (Palaeomutela, Palaeanodonta, Oligodontella, and Opokiella, often occurring in the same strata. The genus Verneuilunio mostly resembles some Late Carboniferous “atypical” unio-like species of the genus Anthraconaia Trueman et Weir. Statistical processing of the biometric parameters of Verneuilunio verneuili and the species A. pruvosti, mostly resembling it, has revealed statistically significant differences in elongation of the posterior end of the shell. To date, the geographic range of the genus Verneuilunio is restricted to the central part of the East European Platform, whereas its stratigraphic range is in the lower sublayer of the Severodvinsk layer.

  20. Composition of fluid inclusions in Permian salt beds, Palo Duro Basin, Texas, U.S.A.

    Science.gov (United States)

    Roedder, E.; d'Angelo, W. M.; Dorrzapf, A.F.; Aruscavage, P. J.

    1987-01-01

    Several methods have been developed and used to extract and chemically analyze the two major types of fluid inclusions in bedded salt from the Palo Duro Basin, Texas. Data on the ratio K: Ca: Mg were obtained on a few of the clouds of tiny inclusions in "chevron" salt, representing the brines from which the salt originally crystallized. Much more complete quantitative data (Na, K, Ca, Mg, Sr, Cl, SO4 and Br) were obtained on ??? 120 individual "large" (mostly ???500 ??m on an edge, i.e., ??? ??? 1.6 ?? 10-4 g) inclusions in recrystallized salt. These latter fluids have a wide range of compositions, even in a given piece of core, indicating that fluids of grossly different composition were present in these salt beds during the several (?) stages of recrystallization. The analytical results indicating very large inter-and intra-sample chemical variation verify the conclusion reached earlier, from petrography and microthermometry, that the inclusion fluids in salt and their solutes are generally polygenetic. The diversity in composition stems from the combination of a variety of sources for the fluids (Permian sea, meteoric, and groundwater, as well as later migrating ground-, formation, or meteoric waters of unknown age), and a variety of subsequent geochemical processes of dissolution, precipitation and rock-water interaction. The compositional data are frequently ambiguous but do provide constraints and may eventually yield a coherent history of the events that produced these beds. Such an understanding of the past history of the evaporite sequence of the Palo Duro Basin should help in predicting the future role of the fluids in the salt if a nuclear waste repository is sited there. ?? 1987.

  1. Body size reductions in nonmammalian eutheriodont therapsids (Synapsida during the end-Permian mass extinction.

    Directory of Open Access Journals (Sweden)

    Adam K Huttenlocker

    Full Text Available The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the 'Lilliput effect,' a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1 active, directional evolution in size traits is rare over macroevolutionary time scales and 2 geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns.

  2. Thermal properties of Permian Basin evaporites to 493 K and 30 MPa confining pressure

    International Nuclear Information System (INIS)

    Durham, W.B.; Heard, H.C.; Boro, C.O.; Keller, K.T.; Ralph, W.E.; Trimmer, D.A.

    1987-01-01

    Laboratory measurements have been made of the thermal conductivity and diffusivity of four rock salts, two anhydrites, and two dolomites bordering the Cycle 4 and Cycle 5 bedded salt formations in the Permian Basin in Deaf Smith County, Texas. Measurement conditions ranged from 303 to 473 K in temperature, and 0.1 to 31.0 MPa in hydrostatic confining pressure. Within the +-5% measurement resolution neither conductivity nor diffusivity showed a dependence upon pressure in any of the rocks. Conductivity and diffusivity in all rocks had a negative temperature dependence. For the two Cycle 4 salt samples, conductivity over the temperature range explored fell from 5.5 to 3.75 W/m.K, and diffusivity fell from about 2.7 to 1.7 x 10 -6 m 2 /s. One of the Cycle 5 salts was a single crystal which had anomalous results, but the other had a low conductivity, about 3.4 W/m.K, with very weak temperature dependence, and a high diffusivity, 3.8 to 2.5 x 10 -6 m 2 /s over the temperature range. In the nonsalts, conductivity and diffusivity decreased 10 to 20% over the temperature range explored, which was 308 -6 m 2 /s for the anhydrites and 1.4 x 10 -6 m 2 /s for both the dolomites. The coefficient of thermal linear expansion was measured for the Cycle 5 salt and nonsalts over 308 -6 K -1 at P = 3.0 MPa to 4 x 10 -6 K -1 at P = 30 MPa for both nonsalt rocks. In anhydrite, it decreased with increasing temperature at a rate of roughly 5 x 10 -8 K -2 at all pressures. In dolomite, the coefficient increased at roughly the same rate. Expansion of the salt ranged from 33 to 38 x 10 -6 K -1 and was independent of pressure and temperature

  3. Body Size Reductions in Nonmammalian Eutheriodont Therapsids (Synapsida) during the End-Permian Mass Extinction

    Science.gov (United States)

    Huttenlocker, Adam K.

    2014-01-01

    The extent to which mass extinctions influence body size evolution in major tetrapod clades is inadequately understood. For example, the ‘Lilliput effect,’ a common feature of mass extinctions, describes a temporary decrease in body sizes of survivor taxa in post-extinction faunas. However, its signature on existing patterns of body size evolution in tetrapods and the persistence of its impacts during post-extinction recoveries are virtually unknown, and rarely compared in both geologic and phylogenetic contexts. Here, I evaluate temporal and phylogenetic distributions of body size in Permo-Triassic therocephalian and cynodont therapsids (eutheriodonts) using a museum collections-based approach and time series model fitting on a regional stratigraphic sequence from the Karoo Basin, South Africa. I further employed rank order correlation tests on global age and clade rank data from an expanded phylogenetic dataset, and performed evolutionary model testing using Brownian (passive diffusion) models. Results support significant size reductions in the immediate aftermath of the end-Permian mass extinction (ca. 252.3 Ma) consistent with some definitions of Lilliput effects. However, this temporal succession reflects a pattern that was underscored largely by Brownian processes and constructive selectivity. Results also support two recent contentions about body size evolution and mass extinctions: 1) active, directional evolution in size traits is rare over macroevolutionary time scales and 2) geologically brief size reductions may be accomplished by the ecological removal of large-bodied species without rapid originations of new small-bodied clades or shifts from long-term evolutionary patterns. PMID:24498335

  4. Coastal dune facies, Permian Cutler Formation (White Rim Sandstone), Capitol Reef National Park area, southern Utah

    Science.gov (United States)

    Kamola, Diane L.; Chan, Marjorie A.

    1988-04-01

    The Permian Cutler Formation (White Rim Sandstone) in the Capitol Reef National Park area in southern Utah is an excellent example of a coastal dune complex subjected to periodic flooding by marine waters. Wind-ripple, grainfall and grainflow laminae compose the cross-sets deposited by eolian dunes. However, wave-reworked structures such as oscillation ripples, the occurrence of the characteristically marine trace fossils Thalassinoides and Chondrites, and interfingering marine carbonate beds of the Kaibab Formation collectively indicate marine interaction with the eolian environment. Four facies are distinguished: cross-stratified sandstone, burrowed to bioturbated sandstone, brecciated and deformed sandstone, and ripple-laminated sandstone and thin carbonate beds. One unusual aspect of the cross-stratified sandstone facies is the abundance of coarse-grained sand. Coarse-grained sand is atypical in many ancient eolian slipface deposits, but occurs here in large slipface foresets as both grainflow and wind-ripple deposits. No water-laid structures are found in these slipface deposits. Coarse-grained sand was probably transported to the Cutler shoreline by fluvial systems draining the Uncompahgre Uplift to the east, and then concentrated as coarse-grained ripples in interdune areas. Some of these coarse-grained ripples migrated up the stoss side of the dunes and accumulations of coarse-grained sand avalanched down the crest to form grainflow deposits. An extensive amount of soft-sediment deformation is indicated by the presence of convolute bedding and brecciation. These features occur near the zone of interfingering with marine carbonate beds of the Kaibab Formation. The water-saturated and moist conditions required for extensive deformation may have been controlled by the proximity of these sandstones to the shoreline, and fluctuations in the associated groundwater table.

  5. Astronomical tuning of the end-Permian extinction and the Early Triassic Epoch of South China and Germany

    Science.gov (United States)

    Li, Mingsong; Ogg, James; Zhang, Yang; Huang, Chunju; Hinnov, Linda; Chen, Zhong-Qiang; Zou, Zhuoyan

    2016-05-01

    The timing of the end-Permian mass extinction and subsequent prolonged recovery during the Early Triassic Epoch can be established from astronomically controlled climate cycles recorded in continuous marine sedimentary sections. Astronomical-cycle tuning of spectral gamma-ray logs from biostratigraphically-constrained cyclic stratigraphy through marine sections at Meishan, Chaohu, Daxiakou and Guandao in South China yields an integrated time scale for the Early Triassic, which is consistent with scaling of magnetostratigraphy from climatic cycles in continental deposits of the Germanic Basin. The main marine mass extinction interval at Meishan is constrained to less than 40% of a 100-kyr (kilo-year) cycle (i.e., marine reptiles in the Mesozoic at Chaohu that are considered to represent a significant recovery of marine ecosystems did not appear until 4.7 myr (million years) after the end-Permian extinction. The durations of the Griesbachian, Dienerian, Smithian and Spathian substages, including the uncertainty in placement of widely used conodont biostratigraphic datums for their boundaries, are 1.4 ± 0.1, 0.6 ± 0.1, 1.7 ± 0.1 and 1.4 ± 0.1 myr, implying a total span for the Early Triassic of 5.1 ± 0.1 myr. Therefore, relative to an assigned 251.902 ± 0.024 Ma for the Permian-Triassic boundary from the Meishan GSSP, the ages for these substage boundaries are 250.5 ± 0.1 Ma for base Dienerian, 249.9 ± 0.1 Ma for base Smithian (base of Olenekian stage), 248.2 ± 0.1 Ma for base Spathian, and 246.8 ± 0.1 Ma for the base of the Anisian Stage. This astronomical-calibrated timescale provides rates for the recurrent carbon isotope excursions and for trends in sedimentation accumulation through the Early Triassic of studied sections in South China.

  6. Source and Extent of Volcanic Ashes at the Permian-Triassic Boundary in South China and Its implications

    Science.gov (United States)

    Wang, M.; Zhong, Y. T.; Hou, Y. L.; He, B.

    2017-12-01

    Highly correlated with the Permian-Triassic Boundary (PTB) Mass Extinction in stratigraphic section, volcanic ashes around the P-T Boundary in South China have been suggested to be a likely cause of the PTB Mass Extinction. So the nature, source and extent of these volcanic ashes have great significance in figuring out the cause of the PTB Mass Extinction. In this study, we attempt to constrain the source and extent of the PTB volcanic ashes in South China by studying pyroclastic sedimentary rocks and the spatial distribution of tuffs and ashes in South China. The detrital zircons of tuffaceous sandstones from Penglaitan section yield an age spectrum peaked at 252Ma, with ɛHf(t) values varying from -20 to -5 ,and have Nb/Hf, Th/Nb and Hf/Th ratios similar to those from arc/orogenic-related settings. Coarse tuffaceous sandstones imply that their source is in limited distance. Those pyroclastic sedimentary rocks in Penglaitan are well correlated with the PTB volcanic ashes in Meishan GSSP section in stratigraphy. In the spatial distribution, pyroclastic sedimentary rocks and tuffs distribute only in southwest of South China, while finer volcanic ashes are mainly in the northern part. This spatial distribution suggests the source of tuffs and ashes was to the south or southwest of South China. Former studies especially that of Permian-Triassic magmatism in Hainan Island have supported the existence of a continental arc related to the subduction and closure of Palaeo-Tethys on the southwestern margin of South China during Permian to early Triassic. It is suggested that the PTB ashes possibly derived from this Paleo-Tethys continental arc. The fact that volcanic ashes haven't been reported or found in PTB stratum in North China or Northwest China implies a limited extent of the volcanism, which thus is too small to cause the PTB mass extinction.

  7. Carboniferous - Early Permian magmatic evolution of the Bogda Range (Xinjiang, NW China): Implications for the Late Paleozoic accretionary tectonics of the SW Central Asian Orogenic Belt

    Science.gov (United States)

    Wali, Guzalnur; Wang, Bo; Cluzel, Dominique; Zhong, Linglin

    2018-03-01

    The Late Paleozoic magmatic evolution of the Bogda Range (Chinese North Tianshan) is important for understanding the accretionary history of the Central Asian Orogenic Belt. We investigated the Carboniferous and Lower Permian volcanic and sedimentary sequences of the Daheyan section, southern Bogda Range, and present new zircon U-Pb ages and whole-rock geochemical data for the volcanic rocks. One Carboniferous rhyolite is dated at 298 ± 8 Ma; a Permian basalt yielded many Proterozoic zircon xenocrysts, and its maximum age (∼297 Ma) is constrained by the detrital zircon ages of the sandstone that stratigraphically underlies it. These volcanic rocks belong to calc-alkaline series. We further synthesize previous geochronological, geochemical and isotopic data of magmatic and sedimentary rocks in the Bogda Range. The available data indicate that the magmatism occurred continuously from 350 Ma to 280 Ma. A comprehensive analysis allows us to propose that: (1) the Carboniferous to Early Permian magmatic rocks of the Bogda Range generally show consistent arc-type features; (2) increasing mantle input through time suggests intra-arc extension in a supra-subduction zone; (3) the localized occurrence of Early Permian alkaline pillow basalts and deep water sediments close to the major shear zone advocate a transtensional crustal thinning during the transition from Carboniferous convergence to Early Permian transcurrent tectonics; (4) occurrence of a large number of Proterozoic zircon xenocrysts in the Late Paleozoic magmatic rocks, and Proterozoic detrital zircons in the coeval clastic sediments suggest a continental or transitional basement of the Bogda Arc; (5) subduction in the Bogda area terminated prior to the deposition of Middle Permian terrestrial sediments.

  8. Evidence for Late Permian-Upper Triassic ocean acidification from calcium isotopes in carbonate of the Kamura section in Japan

    Science.gov (United States)

    Ye, F.; Zhao, L., Sr.; Chen, Z. Q.; Wang, X.

    2017-12-01

    Calcium and carbon cycles are tightly related in the ocean, for example, through continental weathering and deposition of carbonate, thus, very important for exploring evolutions of marine environment during the earth history. The end-Permian mass extinction is the biggest biological disaster in the Phanerozoic and there are several studies talking about variations of calcium isotopes across the Permian-Triassic boundary (PTB). However, these studies are all from the Tethys regions (Payne et al., 2010; Hinojosa et al., 2012), while the Panthalassic Ocean is still unknown to people. Moreover, evolutions of the calcium isotopes during the Early to Late Triassic is also poorly studied (Blattler et al., 2012). Here, we studied an Uppermost Permian to Upper Triassic shallow water successions (Kamura section, Southwest Japan) in the Central Panthalassic Ocean. The Kamura section is far away from the continent without any clastic pollution, therefore, could preserved reliable δ44/40Cacarb signals. Conodont zonation and carbonate carbon isotope also provide precious time framework which is necessary for the explaining of the δ44/40Cacarb profile. In Kamura, δ44/40Cacarb and δ13Ccarb both exhibit negative excursions across the PTB, the δ44/40Cacarb value in the end-Permian is 1.0398‰ then abrupt decrease to the minimum value of 0.1524‰. CO2-driven global ocean acidification best explains the coincidence of the δ44/40Cacarb excursion with negative excursions in the δ13Ccarb of carbonates until the Early Smithian(N1a, N1b, N1c, P1, N2, P2). In the Middle and the Late Triassic, the δ44/40 Cacarb average approximately 1.1‰. During the Middle and Late Triassic, strong relationships between δ44/40Cacarb and δ13Ccarb are collapsed, indicating a normal pH values of the seawater in those time. The Siberian Trap volcanism probably played a significant role on the δ44/40Cacarb until the late Early Triassic. After that, δ44/40Cacarb was mostly controlled by carbonate

  9. Timing of global regression and microbial bloom linked with the Permian-Triassic boundary mass extinction: implications for driving mechanisms

    Science.gov (United States)

    Baresel, Bjoern; Bucher, Hugo; Bagherpour, Borhan; Brosse, Morgane; Guodun, Kuang; Schaltegger, Urs

    2017-04-01

    High-precision U-Pb dating of single-zircon crystals by chemical abrasion-isotope dilution-thermal ionization mass spectrometry (CA-ID-TIMS) is applied to volcanic beds that are intercalated in sedimentary sequences across the Permian-Triassic boundary (PTB). By assuming that the zircon crystallization age closely approximate that of the volcanic eruption and subsequent deposition, U-Pb zircon geochronology is the preferred approach for dating abiotic and biotic events, such as the formational PTB and the Permian-Triassic boundary mass extinction (PTBME). We will present new U-Pb zircon dates for a series of volcanic ash beds in shallow-marine Permian-Triassic sections in the Nanpanjiang Basin, South China. These high-resolution U-Pb dates indicate a duration of 90 ± 38 kyr for the Permian sedimentary hiatus and a duration of 13 ± 57 kyr for the overlying Triassic microbial limestone in the shallow water settings of the Nanpanjiang pull apart Basin. The age and duration of the hiatus coincides with the formational PTB and the extinction interval in the Meishan Global Stratotype Section and Point, thus strongly supporting a glacio-eustatic regression, which best explains the genesis of the worldwide hiatus straddling the PTB in shallow water records. In adjacent deep marine troughs, rates of sediment accumulation display a six-fold decrease across the PTB compatible with a dryer and cooler climate during the Griesbachian as indicated by terrestrial plants. Our model of the PTBME hinges on the synchronicity of the hiatus with the onset of the Siberian Traps volcanism. This early eruptive phase likely released sulfur-rich volatiles into the stratosphere, thus simultaneously eliciting a short-lived ice age responsible for the global regression and a brief but intense acidification. Abrupt cooling, shrunk habitats on shelves and acidification may all have synergistically triggered the PTBME. Subsequently, the build-up of volcanic CO2 induced this transient cool

  10. The present is not the key to the past: A polar forest from the Permian of Antarctica

    International Nuclear Information System (INIS)

    Taylor, E.L.; Taylor, T.N.; Cuneo, N.R.

    1992-01-01

    An in situ Upper Permian fossil forest in the central Transantarctic Mountains near the Beardmore Glacier includes 15 permineralized trunks in growth position; the paleolatitude of the site was approximately 80 degree to 85 degree south. Numerous leaves of the seed fern Glossopteris are present in the shale in which the trunks are rooted. The trunks are permineralized and tree rings reveal that the forest was a rapidly growing and young forest, persisting in an equable, strongly seasonal climate - a scenario that does not fit with some climate reconstructions for this time period

  11. Boron isotopes in brachiopods during the end-Permian mass extinction: constraints on pH evolution and seawater chemistry

    Science.gov (United States)

    Jurikova, Hana; Gutjahr, Marcus; Liebetrau, Volker; Brand, Uwe; Posenato, Renato; Garbelli, Claudio; Angiolini, Lucia; Eisenhauer, Anton

    2017-04-01

    The global biogeochemical cycling of carbon is fundamental for life on Earth with the ocean playing a key role as the largest and dynamically evolving CO2 reservoir. The boron isotope composition (commonly expressed in δ11B) of marine calcium carbonate is considered to be one of the most reliable paleo-pH proxies, potentially enabling us to reconstruct past ocean pH changes and understand carbon cycle perturbations along Earth's geological record (e.g. Foster et al., 2008; Clarkson et al., 2015). Brachiopods present an advantageous and largely underutilised archive for Phanerozoic carbon cycle reconstructions considering their high abundance in the geological record and its origin dating back to the early Cambrian. Moreover, their shell made of low-magnesium calcite makes these marine calcifiers more resistant to post-depositional diagenetic alteration of primary chemical signals. We have investigated the δ11B using MC-ICP-MS (Neptune Plus) and B/Ca and other elemental ratios (Mg/Ca, Sr/Ca, Al/Ca, Li/Ca, Ba/Ca, Na/Ca and Fe/Ca) using ICP-MS-Quadrupole (Agilent 7500cx) from the same specimens in pristine brachiopod shells from two sections from northern Italy during the Late Permian. These sections cover the δ13C excursion in excess of ˜4 ‰ (Brand et al., 2012) and are associated with major climate and environmental perturbations that lead to the mass extinction event at the Permian-Triassic boundary. Particular emphasis will be placed on the implications of our new paleo-pH estimates on the seawater chemistry during the Late Permian. Brand, U., Posenato, R., Came, R., Affek, H., Angiolini, L., Azmy, K. and Farabegoli, E.: The end-Permian mass extinction: A rapid volcanic CO2 and CH4-climatic catastrophe, Chemical Geology 323, 121-144, doi:10.1016/j.chemgeo.2012.06.015, 2012. Clarkson, M.O., Kasemann, S.A., Wood, R.A., Lenton, T.M., Daines, S.J., Richoz, S., Ohnemueller, F., Meixner, A., Poulton, S.W. and Tipper, E.T.: Ocean acidification and the Permo

  12. Enhanced recycling of organic matter and Os-isotopic evidence for multiple magmatic or meteoritic inputs to the Late Permian Panthalassic Ocean, Opal Creek, Canada

    Science.gov (United States)

    Georgiev, Svetoslav V.; Stein, Holly J.; Hannah, Judith L.; Henderson, Charles M.; Algeo, Thomas J.

    2015-02-01

    The geochemical record for the Permian-Triassic boundary in northern latitudes is essential to evaluation of global changes associated with the most profound extinction of life on Earth. We present inorganic and organic geochemical data, and Re-Os isotope systematics in a critical stratigraphic interval of pre- and post-extinction Upper Permian-Lower Triassic sediments from Opal Creek, western Canada (paleolatitude of ∼30°N). We document significant and long-lived changes in Panthalassa seawater chemistry that were initiated during the first of four magmatic or meteoritic inputs to Late Permian seawater, evidenced by notable decreases of Os isotopic ratios upsection. Geochemical signals indicate establishment of anoxic bottom waters shortly after regional transgression reinitiated sedimentation in the Late Permian. Euxinic signals are most prominent in the Upper Permian sediments with low organic carbon and high sulfur contents, and gradually wane in the Lower Triassic. The observed features may have been generated in a strongly euxinic ocean in which high bacterioplankton productivity sustained prolific microbial sulfate reduction in the sediment and/or water column, providing hydrogen sulfide to form pyrite. This scenario requires nearly complete anaerobic decomposition of predominantly labile marine organic matter (OM) without the necessity for a complete collapse of primary marine productivity. Similar geochemical variations could have been achieved by widespread oxidation of methane by sulfate reducers after a methanogenic burst in the Late Permian. Both scenarios could have provided similar kill mechanisms for the latest Permian mass extinction. Despite the moderate thermal maturity of the section, OM in all studied samples is dominantly terrestrial and/or continentally derived, recycled and refractory ancient OM. We argue that, as such, the quantity of the OM in the section mainly reflects changes in terrestrial vegetation and/or weathering, and not in

  13. Chasing rainbow notions: enacting community psychology in the classroom and beyond in post-1994 South Africa.

    Science.gov (United States)

    Ngonyama ka Sigogo, Thabani; Hooper, Megan; Long, Carol; Lykes, M Brinton; Wilson, Kenneth; Zietkiewicz, Estelle

    2004-03-01

    This paper discusses tensions and contradictions experienced by a group of psychologists in post-1994 South Africa as we struggled to develop an MA program in community psychology. Situating our work within the history of the subdiscipline and the historical context confronting South Africans in the "wake of apartheid," we explore models of community psychology that informed praxis under apartheid and contemporary challenges confronting a country in transition. We discuss three tensions that inform the ongoing program development. These include (1) the construction and deconstruction of Western and indigenous knowledge systems; (2) assessment and intervention at multiple levels and from differing value perspectives; and (3) paradoxes experienced by a team of university-educated, primarily White academic staff committed to challenging oppression. We conclude our discussion by suggesting that, within these shifting sands of economic, political, cultural, and institutional change community psychology must, of necessity, resist rigid self-definition and seek to position itself as a "work-in-progress." We suggest that this seemingly anomalous self-description may be suggestive for other community psychologists-in-the-making facing similar challenges within the majority world.

  14. Paper trail: Chasing the Chinese in the Cape (1904-1933

    Directory of Open Access Journals (Sweden)

    Karen L. Harris

    Full Text Available The Chinese Exclusion Act passed by the Cape parliament in 1904 was one of the first pieces of legislation promulgated in the southern region of Africa where a particular 'racial group' was singled out, documented and discriminated against. Although it had trans-oceanic antecedents and tapped into this global anti-Chinese sentiment, unlike the Chinese exclusion legislation elsewhere, the Cape exclusion legislation targeted the entire Chinese 'race'. This article proposes to trace the application of this unwieldy registration system and show how the small Chinese community was registered, identified, monitored and hounded both on paper and on the ground until well after the repeal of the Act three decades later. Through an analysis of these paper records, the article intends to elucidate the nature of this imposition and consider what they tell us of the Chinese it was imposed upon and how they responded. It also proposes that, while the Act was formulated for exclusion, ironically for just under 1,500 of the Chinese resident at the colonial Cape it eventually warranted a double inclusion, one in the form of a certificate of exemption and hence domicile - albeit with perpetual surveillance and scrutiny - and the other as part of the archived historic record.

  15. Deep time perspective on turtle neck evolution: chasing the Hox code by vertebral morphology.

    Science.gov (United States)

    Böhmer, Christine; Werneburg, Ingmar

    2017-08-21

    The unparalleled ability of turtle neck retraction is possible in three different modes, which characterize stem turtles, living side-necked (Pleurodira), and hidden-necked (Cryptodira) turtles, respectively. Despite the conservatism in vertebral count among turtles, there is significant functional and morphological regionalization in the cervical vertebral column. Since Hox genes play a fundamental role in determining the differentiation in vertebra morphology and based on our reconstruction of evolutionary genetics in deep time, we hypothesize genetic differences among the turtle groups and between turtles and other land vertebrates. We correlated anterior Hox gene expression and the quantifiable shape of the vertebrae to investigate the morphological modularity in the neck across living and extinct turtles. This permitted the reconstruction of the hypothetical ancestral Hox code pattern of the whole turtle clade. The scenario of the evolution of axial patterning in turtles indicates shifts in the spatial expression of HoxA-5 in relation to the reduction of cervical ribs in modern turtles and of HoxB-5 linked with a lower morphological differentiation between the anterior cervical vertebrae observed in cryptodirans. By comparison with the mammalian pattern, we illustrate how the fixed count of eight cervical vertebrae in turtles resulted from the emergence of the unique turtle shell.

  16. Coal petrology of coal seams from the Leao-Butia Coalfield, Lower Permian of the Parana Basin, Brazil - Implications for coal facies interpretations

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M.B. [Laboratorio de Oceanografia Geologica, Departamento de Geociencias, Fundacao Universidade Federal do Rio Grande, FURG, Av. Italia km 08, Campus Carreiros, 96201-900, Rio Grande, RS (Brazil); Kalkreuth, W.; Holz, M. [Instituto de Geociencias, UFRGS, Av. Bento Goncalves, 9500 91501-970 Porto Alegre, RS (Brazil)

    2008-02-01

    In the Leao-Butia Coalfield, Rio Grande do Sul the coal seams occur in the Rio Bonito Formation, Guata Group, Tubarao Supergroup of the Parana Basin, Brazil and are of Permian (Artinskian-Kungurian) age. This study is the first detailed investigation on the coal petrographic characterization of the coal-bearing sequence in relation to the depositional settings of the precursor mires, both in terms of whole seam characterization and in-seam variations. The study is based on the analyses of nine coal seams (I2, CI, L4, L3, L2, L1, S3, S2, S1), which were selected from core of borehole D-193, Leao-Butia and represent the entire coal-bearing sequence. The interpretation of coal facies and depositional environment is based on lithotype, maceral and microlithotype analyses using different facies-critical petrographic indices, which were displayed in coal facies diagrams. The seams are characterized by the predominance of dull lithotypes (dull, banded dull). The dullness of the coal is attributed to relatively high mineral matter, inertinite and liptinite contents. The petrographic composition is dominated by vitrinite (28-70 vol.% mmf) and inertinite (> 30 vol.% mmf) groups. Liptinite contents range from 7 to 30 vol.% (mmf) and mineral matter from 4-30 vol.%. Microlithotypes associations are dominated by vitrite, duroclarite, carbominerite and inertite. It is suggested that the observed vertical variations in petrographic characteristics (lithotypes, microlithotypes, macerals, vitrinite reflectance) were controlled by groundwater level fluctuations in the ancient mires due to different accommodation/peat accumulation rates. Correlation of the borehole strata with the general sequence-stratigraphical setting suggests that the alluvial fan system and the coal-bearing mudstone succession are linked to a late transgressive systems tract of sequence 2. Based on average compositional values obtained from coal facies diagrams, a deposition in a limno-telmatic to limnic coal

  17. Finns det nån här? – Förmedling av paranormala fenomen i TV-serien Chasing the Dead

    OpenAIRE

    Heinänen, Thomas

    2013-01-01

    Genom denna kvalitativa innehållsanalys av TV-serien Chasing the Dead, undersöks på vilket sätt dokumenterade "bevis" på paranormala audiovisuella fenomen har presenterats av seriemakarna. Materialet analyseras med hjälp av forskningsresultat från, för denna TV-genre relevanta, studier av fenomen som Electronic Voice Phenomenon, Electro Magnetic Field, Orber. Biologiska fenomen som Apophenia och Pareidolia har tagits i beaktande då materialet har analyserats. Syftet med denna underso...

  18. Properties of Halococcus salifodinae, an Isolate from Permian Rock Salt Deposits, Compared with Halococci from Surface Waters

    Directory of Open Access Journals (Sweden)

    Helga Stan-Lotter

    2013-02-01

    Full Text Available Halococcus salifodinae BIpT DSM 8989T, an extremely halophilic archaeal isolate from an Austrian salt deposit (Bad Ischl, whose origin was dated to the Permian period, was described in 1994. Subsequently, several strains of the species have been isolated, some from similar but geographically separated salt deposits. Hcc. salifodinae may be regarded as one of the most ancient culturable species which existed already about 250 million years ago. Since its habitat probably did not change during this long period, its properties were presumably not subjected to the needs of mutational adaptation. Hcc. salifodinae and other isolates from ancient deposits would be suitable candidates for testing hypotheses on prokaryotic evolution, such as the molecular clock concept, or the net-like history of genome evolution. A comparison of available taxonomic characteristics from strains of Hcc. salifodinae and other Halococcus species, most of them originating from surface waters, is presented. The cell wall polymer of Hcc. salifodinae was examined and found to be a heteropolysaccharide, similar to that of Hcc. morrhuae. Polyhydroxyalkanoate granules were present in Hcc. salifodinae, suggesting a possible lateral gene transfer before Permian times.

  19. The Triassic dicynodont Kombuisia (Synapsida, Anomodontia) from Antarctica, a refuge from the terrestrial Permian-Triassic mass extinction.

    Science.gov (United States)

    Fröbisch, Jörg; Angielczyk, Kenneth D; Sidor, Christian A

    2010-02-01

    Fossils from the central Transantarctic Mountains in Antarctica are referred to a new species of the Triassic genus Kombuisia, one of four dicynodont lineages known to survive the end-Permian mass extinction. The specimens show a unique combination of characters only present in this genus, but the new species can be distinguished from the type species of the genus, Kombuisia frerensis, by the presence of a reduced but slit-like pineal foramen and the lack of contact between the postorbitals. Although incomplete, the Antarctic specimens are significant because Kombuisia was previously known only from the South African Karoo Basin and the new specimens extend the taxon's biogeographic range to a wider portion of southern Pangaea. In addition, the new finds extend the known stratigraphic range of Kombuisia from the Middle Triassic subzone B of the Cynognathus Assemblage Zone into rocks that are equivalent in age to the Lower Triassic Lystrosaurus Assemblage Zone, shortening the proposed ghost lineage of this taxon. Most importantly, the occurrence of Kombuisia and Lystrosaurus mccaigi in the Lower Triassic of Antarctica suggests that this area served as a refuge from some of the effects of the end-Permian extinction. The composition of the lower Fremouw Formation fauna implies a community structure similar to that of the ecologically anomalous Lystrosaurus Assemblage Zone of South Africa, providing additional evidence for widespread ecological disturbance in the extinction's aftermath.

  20. An exceptionally preserved transitional lungfish from the lower permian of Nebraska, USA, and the origin of modern lungfishes.

    Directory of Open Access Journals (Sweden)

    Jason D Pardo

    Full Text Available Complete, exceptionally-preserved skulls of the Permian lungfish Persephonichthys chthonica gen. et sp. nov. are described. Persephonichthys chthonica is unique among post-Devonian lungfishes in preserving portions of the neurocranium, permitting description of the braincase of a stem-ceratodontiform for the first time. The completeness of P. chthonica permits robust phylogenetic analysis of the relationships of the extant lungfish lineage within the Devonian lungfish diversification for the first time. New analyses of the relationships of this new species within two published matrices using both maximum parsimony and Bayesian inference robustly place P. chthonica and modern lungfishes within dipterid-grade dipnoans rather than within a clade containing Late Devonian 'phaneropleurids' and common Late Paleozoic lungfishes such as Sagenodus. Monophyly of post-Devonian lungfishes is not supported and the Carboniferous-Permian taxon Sagenodus is found to be incidental to the origins of modern lungfishes, suggesting widespread convergence in Late Paleozoic lungfishes. Morphology of the skull, hyoid arch, and pectoral girdle suggests a deviation in feeding mechanics from that of Devonian lungfishes towards the more dynamic gape cycle and more effective buccal pumping seen in modern lungfishes. Similar anatomy observed previously in 'Rhinodipterus' kimberyensis likely represents an intermediate state between the strict durophagy observed in most Devonian lungfishes and the more dynamic buccal pump seen in Persephonichthys and modern lungfishes, rather than adaptation to air-breathing exclusively.

  1. An Exceptionally Preserved Transitional Lungfish from the Lower Permian of Nebraska, USA, and the Origin of Modern Lungfishes

    Science.gov (United States)

    Pardo, Jason D.; Huttenlocker, Adam K.; Small, Bryan J.

    2014-01-01

    Complete, exceptionally-preserved skulls of the Permian lungfish Persephonichthys chthonica gen. et sp. nov. are described. Persephonichthys chthonica is unique among post-Devonian lungfishes in preserving portions of the neurocranium, permitting description of the braincase of a stem-ceratodontiform for the first time. The completeness of P. chthonica permits robust phylogenetic analysis of the relationships of the extant lungfish lineage within the Devonian lungfish diversification for the first time. New analyses of the relationships of this new species within two published matrices using both maximum parsimony and Bayesian inference robustly place P. chthonica and modern lungfishes within dipterid-grade dipnoans rather than within a clade containing Late Devonian ‘phaneropleurids’ and common Late Paleozoic lungfishes such as Sagenodus. Monophyly of post-Devonian lungfishes is not supported and the Carboniferous-Permian taxon Sagenodus is found to be incidental to the origins of modern lungfishes, suggesting widespread convergence in Late Paleozoic lungfishes. Morphology of the skull, hyoid arch, and pectoral girdle suggests a deviation in feeding mechanics from that of Devonian lungfishes towards the more dynamic gape cycle and more effective buccal pumping seen in modern lungfishes. Similar anatomy observed previously in ‘Rhinodipterus’ kimberyensis likely represents an intermediate state between the strict durophagy observed in most Devonian lungfishes and the more dynamic buccal pump seen in Persephonichthys and modern lungfishes, rather than adaptation to air-breathing exclusively. PMID:25265394

  2. Permian salt dissolution, alkaline lake basins, and nuclear-waste storage, Southern High Plains, Texas and New Mexico

    International Nuclear Information System (INIS)

    Reeves, C.C. Jr.; Temple, J.M.

    1986-01-01

    Areas of Permian salt dissolution associated with 15 large alkaline lake basins on and adjacent to the Southern High Plains of west Texas and eastern New Mexico suggest formation of the basins by collapse of strata over the dissolution cavities. However, data from 6 other alkaline basins reveal no evidence of underlying salt dissolution. Thus, whether the basins were initiated by subsidence over the salt dissolution areas or whether the salt dissolution was caused by infiltration of overlying lake water is conjectural. However, the fact that the lacustrine fill in Mound Lake greatly exceeds the amount of salt dissolution and subsidence of overlying beds indicates that at least Mound Lake basin was antecedent to the salt dissolution. The association of topography, structure, and dissolution in areas well removed from zones of shallow burial emphasizes the susceptibility of Permian salt-bed dissolution throughout the west Texas-eastern New Mexico area. Such evidence, combined with previous studies documenting salt-bed dissolution in areas surrounding a proposed high-level nuclear-waste repository site in Deaf Smith County, Texas, leads to serious questions about the rationale of using salt beds for nuclear-waste storage

  3. Irradiation of quartz grains - a new method of sedimentological analysis applied to Permian - Carboniferous arenites in the Maranhao Basin - Brazil

    International Nuclear Information System (INIS)

    Carmo Faria Junior, L.E. do

    1980-01-01

    The quartz grains of sediments and sedimentary rocks change their colour in variable intensity to smoky-quartz by X-ray irradiation, Co 60 or in reactors, dependent on their temperature of cristallization. The quantity of quartz grains which were stained and which were not stained after being irradiated are related to rock types from the source areas. This method was applied for selected sandstones of different stratigraphical levels of the Permian-Carboniferous in the Maranhao Basin of Brazil. Studeis on heavy minerals of these sandstones have been done before. The heavy mineral associations of the Permian Pedra de Fogo Formation corroborate the results of the analysis of quartz grains which indicate a predominance of the metamorphic rocks in the source area. However, the heavy mineral parageneses of the Carboniferous Piaui Formation are different. This may be because the frequency of those heavy minerals depend directly on the stage of the weathering of the sandstones. It should be mentioned that heavy minerals occur in paleozoic sediments only in a small quantity, sometimes below 1% of the rock constitution. The irradiation analysis, which is applied for the predominant mineral in sandstones, appears to be most reliable. It is used here as the basis for the interpretations presented. (Author) [pt

  4. Regional summary and recommended study areas for the Texas panhandle portion of the Permian Basin. Technical report

    International Nuclear Information System (INIS)

    1979-10-01

    This report summarizes the regional geologic and environmental characterizations that have been completed for the Permian region of study, and describes the procedure used to identify study areas for the next phase of investigation. The factors evaluated in the Permian region fall into three broad areas: health and safety, environmental and socioeconomic, and engineering and economic considerations. Health and safety considerations included salt depth and thickness, faults, seismic activity, groundwater, salt dissolution, energy and mineral resources, presence of boreholes, and interactive land uses. Salt depth and thickness was the key health and safety factor, and when mapped, proved to be a discriminator. The evaluation of environmental and socioeconomic conditions focused primarily on the presence of urban areas and on designated land uses such as parks, wildlife areas, and historic sites. Engineering and economic considerations centered primarily on salt depth, which was already evaluated in the health and safety area. The Palo Duro and Dalhart basins are recommended for future studies on the basis of geology. In these two basins, salt depth and thickness appear promising, and there is less likelihood of past or future oil and gas exploratory holes. Environmental and socioeconomic factors did not preclude any of the basins from further study

  5. Rock mechanics evaluation of potential repository sites in the Paradox, Permian, and Gulf Coast Basins: Volume 1

    International Nuclear Information System (INIS)

    1987-09-01

    Thermal and thermomechanical analyses of a conceptual radioactive waste repository containing commercial and defense high-level wastes and spent fuel have been performing using finite element models. The thermal and thermomechanical responses of the waste package, disposal room, and repository regions were evaluated. four bedded salt formations, in Davis and Lavender Canyons in the Paradox Basin of southeastern Utah and in Deaf Smith and Swisher counties in the Permian Basin of northwestern Texas, and three salt domes, Vacherie Dome in northwestern Louisiana and Richton and Cypress Creek Domes in southeastern Mississippi, located in the Gulf Coast Basin, were examined. In the Paradox Basin, the pressure exerted on the waste package overpack was much greater than the initial in situ stress. The disposal room closure was less than 10 percent after 5 years. Surface uplift was nominal, and no significant thermomechanical perturbation of the aquitards was observed. In the Permian Basin, the pressure exerted on the waste package overpack was greater than the initial in situ stress. The disposal room closures were greater than 10 percent in less than 5 years. Surface uplift was nominal, and no significant thermomechanical perturbation of the aquitards was observed. In the Gulf Coast Basin, the pressure exerted on the waste package overpack was greater than the initial in situ stress. The disposal room closures were greater than 10 percent in less than 5 years. No significant thermomechanical perturbation of the overlying geology was observed. 40 refs., 153 figs., 32 tabs

  6. Insuring Water Sustainability for Resource Extraction in the New Mexico Permian Basin

    Science.gov (United States)

    Lowry, T. S.; Schuhen, M. D.; Lofton, O. W.; Walker, L. T. N.; Johnson, P. B.; Land, L. A.; Herrell, D.

    2017-12-01

    Advancements in directional drilling and well completion technologies have resulted in an exponential growth in the use of hydraulic fracturing for oil and gas extraction. Within the New Mexico portion of the Permian Basin (see figure), water demand to complete each hydraulically fractured well is estimated to average 7.3 acre-feet (2.4 million gallons), which has resulted in an increase in the regional water demand of over 5000 acre-feet per year. The rise in demand along with proposed rule changes that govern the regulation and management of hydraulic fracturing on Federal and Indian lands (40 CFS 3160) has created concern as to the regions ability to meet the demand in a manner that can sustainably meet the needs of the variety of water users and other stakeholders in the region while also protecting human health and the environment. Funded by the Bureau of Land Management who is charged with managing the regions water resources on Federal lands, this project is addressing those concerns using a multi-disciplinary approach that synthesizes data collection, field verification, and system dynamics (SD) modeling to better understand the dynamics of the regional water supply and demand under different management, policy, and growth scenarios. The scientific challenge has been in bringing together disparate data in a manner that exposes the temporal and spatial dynamics of the regional water supply in the context of increasing demands and changing policy and management scenarios. Field verification and testing activities are used to evaluate existing borehole data to insure that the data are accurate and up to date. The SD model simulates forecasted increases in drilling activity and water demand relative to each water source to identify areas that are most vulnerable and to estimate risk to water sustainability. Key to this is the models ability to seamlessly handle uncertainty such that it produces probabilistic outputs that allow decision makers to explore and

  7. Sedimentary and environmental history of the Late Permian Bonikowo Reef (Zechstein Limestone, Wuchiapingian, western Poland

    Directory of Open Access Journals (Sweden)

    Paweł Raczyński

    2017-07-01

    Full Text Available The Bonikowo Reef occurs in the central part of the Zechstein Limestone Basin in western Poland and was growing on the topmost edges of tilted blocks and/or on the top of uplifted horsts of the Brandenburg–Wolsztyn–Pogorzela High. Its size is ca. 1.6 km2. The Bonikowo Reef shows the thickest reef section (90.5 m recorded in the High. The Zechstein Limestone unit is represented mostly by limestones, often thoroughly recrystallized, although the macrotextures and biota of the boundstone are identifiable in most cases. The drillcore section is a mixture of boundstones (microbial and bryozoan, wackestones, packstones and grainstones, which often co-occur. The δ13C and δ18O values for both calcite (avg. 3.8 ± 0.8‰ and −3.4 ± 1.7‰, respectively and dolomite (avg. 3.5 ± 0.7‰ and −5.2 ± 1.3‰, respectively are transitional between the values previously reported for condensed sequences of the basinal facies and larger reef complexes. The biofacies of the Bonikowo Reef are very similar to those recognized in other reefs of the Brandenburg–Wolsztyn–Pogorzela High, which owe their origin to the destruction of bryozoan boundstones. The biota composition is typical and characteristic of other Zechstein Limestone reefs. However, the Bonikowo Reef demonstrates the importance of microbialites, laminar and nodose encrustations, in the growth and cohesion of the Zechstein Limestone reefs. Such encrustations abound within the Zechstein Limestone although, in many cases, the real nature of the encrustations is difficult to ascertain. These laminated encrustations show great similarity to Archaeolithoporella that is one of the most important Permian reef-building organisms. The encrustations considered to represent Archaeolithoporella were also previously recorded in the Zechstein Limestone of western Poland and in its stratigraphic equivalent, the Middle Magnesian Limestone of Northeast England. The lower part of the sequence shows

  8. OIL RESERVOIR CHARACTERIZATION AND CO2 INJECTION MONITORING IN THE PERMIAN BASIN WITH CROSSWELL ELECTROMAGNETIC IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    Michael Wilt

    2004-02-01

    Substantial petroleum reserves exist in US oil fields that cannot be produced economically, at current prices, unless improvements in technology are forthcoming. Recovery of these reserves is vital to US economic and security interests as it lessens our dependence on foreign sources and keeps our domestic petroleum industry vital. Several new technologies have emerged that may improve the situation. The first is a series of new flooding techniques to re-pressurize reservoirs and improve the recovery. Of these the most promising is miscible CO{sub 2} flooding, which has been used in several US petroleum basins. The second is the emergence of new monitoring technologies to track and help manage this injection. One of the major players in here is crosswell electromagnetics, which has a proven sensitivity to reservoir fluids. In this project, we are applying the crosswell EM technology to a CO{sub 2} flood in the Permian Basin oil fields of New Mexico. With our partner ChevronTexaco, we are testing the suitability of using EM for tracking the flow of injected CO{sub 2} through the San Andreas reservoir in the Vacuum field in New Mexico. The project consisted of three phases, the first of which was a preliminary field test at Vacuum, where a prototype system was tested in oil field conditions including widely spaced wells with steel casing. The results, although useful, demonstrated that the older technology was not suitable for practical deployment. In the second phase of the project, we developed a much more powerful and robust field system capable of collecting and interpreting field data through steel-cased wells. The final phase of the project involved applying this system in field tests in the US and overseas. Results for tests in steam and water floods showed remarkable capability to image between steel wells and provided images that helped understand the geology and ongoing flood and helped better manage the field. The future of this technology is indeed bright

  9. Latest Permian carbonate carbon isotope variability traces heterogeneous organic carbon accumulation and authigenic carbonate formation

    Directory of Open Access Journals (Sweden)

    M. Schobben

    2017-11-01

    Full Text Available Bulk-carbonate carbon isotope ratios are a widely applied proxy for investigating the ancient biogeochemical carbon cycle. Temporal carbon isotope trends serve as a prime stratigraphic tool, with the inherent assumption that bulk micritic carbonate rock is a faithful geochemical recorder of the isotopic composition of seawater dissolved inorganic carbon. However, bulk-carbonate rock is also prone to incorporate diagenetic signals. The aim of the present study is to disentangle primary trends from diagenetic signals in carbon isotope records which traverse the Permian–Triassic boundary in the marine carbonate-bearing sequences of Iran and South China. By pooling newly produced and published carbon isotope data, we confirm that a global first-order trend towards depleted values exists. However, a large amount of scatter is superimposed on this geochemical record. In addition, we observe a temporal trend in the amplitude of this residual δ13C variability, which is reproducible for the two studied regions. We suggest that (sub-sea-floor microbial communities and their control on calcite nucleation and ambient porewater dissolved inorganic carbon δ13C pose a viable mechanism to induce bulk-rock δ13C variability. Numerical model calculations highlight that early diagenetic carbonate rock stabilization and linked carbon isotope alteration can be controlled by organic matter supply and subsequent microbial remineralization. A major biotic decline among Late Permian bottom-dwelling organisms facilitated a spatial increase in heterogeneous organic carbon accumulation. Combined with low marine sulfate, this resulted in varying degrees of carbon isotope overprinting. A simulated time series suggests that a 50 % increase in the spatial scatter of organic carbon relative to the average, in addition to an imposed increase in the likelihood of sampling cements formed by microbial calcite nucleation to 1 out of 10 samples, is sufficient to induce the

  10. EVALUATION OF PHYTOTOXIC EFFECT OF DELETERIOUS RHIZOBACTERIA ON THE ROOT GROWTH OF AXONOPUS AFFINIS (CHASE AND LENS ESCULENTA (MOENCH

    Directory of Open Access Journals (Sweden)

    X.J Pacheco-Hernández

    2015-11-01

    Full Text Available Las malezas ocasionan una gran pérdida en las tierras agrícolas y comúnmente, las medidas de manejo y contención de estas especies se dan con la aplicación de herbicidas, sin embargo; en años recientes se ha presentado un interés en establecer mecanismos de biocontrol seguros, con el empleo de bacterias inhibidoras del crecimiento conocidas como rizobacterias deletéreas (Deleterious rhizobacteria: DRBque se consideran generalmente como no parasíticas, y causan, de manera sutil, efectos deletéreos a través de la producción de metabolitos dañinos a las plantas. El presente trabajo tuvo como objetivo caracterizar la producción de ácido cianhídrico de pseudomonas rizobacterianas de malezas de un cultivo de alfalfa (Medicago sativa L. y evaluar el efecto fitotóxico de éstas sobre el crecimiento radical de plántulas de Axonopus affinis (Chase y Lens esculenta (Moench. De acuerdo con los resultados obtenidos con relación a la evidencia de que los aislados de pseudomonadas son rizobacterias cianogénicas y de su efecto fitotóxico medido sobre las especies vegetales bajo estudio; se sugieren a éstas como posibles agentes de biocontrol con pastos que sean considerados malezas; ya que en general se observó que inhiben su crecimiento radical; sin embargo, un enfoque particular lo tiene la rizobacteria Pseudomonas sp. A52, la cual presentó no solamente actividad como una DRB sino también como una rizobacteria promotora del crecimiento vegetal; lo que la hace más importante de analizar en cuanto a su potencial y espectro de acción; tanto para malezas monocotiledóneas como para dicotiledóneas, recomendable como un posible agente de biocontrol con actividad múltiple.

  11. Chase the direct impact of rainfall into groundwater in Mt. Fuji from multiple analyses including microbial DNA

    Science.gov (United States)

    Kato, Kenji; Sugiyama, Ayumi; Nagaosa, Kazuyo; Tsujimura, Maki

    2016-04-01

    A huge amount of groundwater is stored in subsurface environment of Mt. Fuji, the largest volcanic mountain in Japan. Based on the concept of piston flow transport of groundwater an apparent residence time was estimated to ca. 30 years by 36Cl/Cl ratio (Tosaki et al., 2011). However, this number represents an averaged value of the residence time of groundwater which had been mixed before it flushes out. We chased signatures of direct impact of rainfall into groundwater to elucidate the routes of groundwater, employing three different tracers; stable isotopic analysis (delta 18O), chemical analysis (concentration of silica) and microbial DNA analysis. Though chemical analysis of groundwater shows an averaged value of the examined water which was blended by various water with different sources and routes in subsurface environment, microbial DNA analysis may suggest the place where they originated, which may give information of the source and transport routes of the water examined. Throughout the in situ observation of four rainfall events showed that stable oxygen isotopic ratio of spring water and shallow groundwater obtained from 726m a.s.l. where the average recharge height of rainfall was between 1500 and 1800 m became higher than the values before a torrential rainfall, and the concentration of silica decreased after this event when rainfall exceeded 300 mm in precipitation of an event. In addition, the density of Prokaryotes in spring water apparently increased. Those changes did not appear when rainfall did not exceed 100 mm per event. Thus, findings shown above indicated a direct impact of rainfall into shallow groundwater, which appeared within a few weeks of torrential rainfall in the studied geological setting. In addition, increase in the density of Archaea observed at deep groundwater after the torrential rainfall suggested an enlargement of the strength of piston flow transport through the penetration of rainfall into deep groundwater. This finding was

  12. Sedimentary architecture and palaeogeography of lower Slochteren Aeolian cycles from the Rotliegend desert-lake margin (Permian), the Markham area, Southern North Sea

    NARCIS (Netherlands)

    Belt, F.J.G. van den; Hulten, F.F.N. van

    2011-01-01

    The Rotliegend gas play in the Southern Permian Basin has yielded over 200 gas fields in the Netherlands; they are found in an E-W fairway along the southern flank of the basin. Sandstones generally pinch out basinward, but localized, isolated sands are present north of the main fairway. The

  13. Problems and challenges in detection of pre-Mesozoic maar volcanoes: example from the Principálek Volcano in the Permian Krkonoše Piedmont Basin

    Czech Academy of Sciences Publication Activity Database

    Valenta, Jan; Rapprich, V.; Stárková, M.; Skácelová, Z.; Fojtíková, Lucia; Staněk, František; Balek, Jan

    2014-01-01

    Roč. 59, č. 3 (2014), s. 169-181 ISSN 1802-6222 Institutional support: RVO:67985891 Keywords : diatreme * geophysics * volcanology * Permian * Krkonoše Piedmont Basin Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.405, year: 2014 http://www.jgeosci.org/detail/jgeosci.170

  14. Preliminary study of uranium in Pennsylvanian and lower Permian strata in the Powder River Basin, Wyoming and Montana, and the Northern Great Plains

    International Nuclear Information System (INIS)

    Dunagan, J.F. Jr.; Kadish, K.A.

    1977-11-01

    Persistent and widespread radiometric anomalies occur in Pennsylvanian and Lower Permian strata in the subsurface of the northern Great Plains and the Powder River Basin. The primary host lithology of these anomalies is shale interbedded with sandstone, dolomite, and dolomitic sandstone. Samples from the project area indicate that uranium is responsible for some anomalies. In some samples there seems to be a correlation between high uranium content and high organic-carbon content, which possibly indicates that carbonaceous material acted as a trapping mechanism in some strata. The Pennsylvanian and Permian rocks studied are predominantly marine carbonates and clastics, but there are rocks of fluvial origin in the basal Pennsylvanian of Montana, North Dakota, and South Dakota and in the Pennsylvanian and Permian deposits on the east flank of the Laramie Mountains. Fine-grained clastic rocks that flank the Chadron arch in western Nebraska are possibly of continental origin. The trend of the Chadron arch approximately parallels the trend of radiometric anomalies in the subsurface Permian-Pennsylvanian section. Possible source areas for uranium in the sediments studied were pre-Pennsylvanian strata of the Canadian Shield and Precambrian igneous rocks of the Ancestral Rocky Mountains

  15. A 25 million year macrofloral record (Carboniferous-Permian) in the Czech part of the Intra-Sudetic Basin, biostratigraphy, plant diversity and vegetation patterns

    Czech Academy of Sciences Publication Activity Database

    Opluštil, S.; Šimůnek, Z.; Pšenička, J.; Bek, Jiří; Libertín, M.

    2017-01-01

    Roč. 244, SEP 2017 (2017), s. 241-307 ISSN 0034-6667 R&D Projects: GA ČR GAP210/12/2053 Institutional support: RVO:67985831 Keywords : Early Permian * floral zonation * Intra-Sudetic Basin * Pennsylvanian * plant diversity * plant taphonomy * vegetation patterns Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.817, year: 2016

  16. Summary of the stratigraphy, sedimentology, and mineralogy of Pennsylvanian and permian rocks of Oklahoma in relation to uranium-resource potential

    International Nuclear Information System (INIS)

    Olmsted, R.W.; Hanson, R.E.; May, R.T.; Owens, R.T.

    1976-01-01

    Pennsylvanian-Permian strata in Oklahoma were deposited in environments which ranged from deep marine to alluvial fan. The former was most common in the Ouachita geosyncline during Early Pennsylvanian, but parts of the Anadarko basin were also relatively deep water during Middle and Late Pennsylvanian. Alluvial-fan deposits in Oklahoma are related primarily to the Amarillo-Wichita-Criner, Arbuckle, and Ouachita uplifts. As a result of erosion of the Wichita and Arbuckle areas during the Pennsylvanian-Permian, Precambrian and Cambrian felsic igneous rocks were exposed and became sources of significant quantities of feldspar in the sandstones and conglomerates, especially those on the flanks of the uplifts, and possibly sources of significant uranium concentrations in basinal waters. The Ouachita uplift, Sierra Grande-Apishapa uplift to the northwest, and possibly the Appalachian system also furnished feldspar to form the rather common subarkoses in the Upper Pennsylvanian-Permian. Feldspar is an apparent source of uranium which is present in the alluvial-fan deposits associated with the Wichita and Arbuckle uplifts, the Permian sandstones on oil-producing structures in southern Oklahoma, the lenticular sandstones on the Muenster-Waurika arch, and the tidal-flat sandstone-siltstones in western Oklahoma and possibly in north-central Oklahoma. Radioactive anomalies associated with Cherokee sandstones may be related to the Desmoinesian phosphatic shales, local depositional environments of deltaic complexes which influenced diagenetic conditions, and/or the pre-Pennsylvanian unconformity with respect to the radioactive Woodford Shale

  17. PLAY ANALYSIS AND DIGITAL PORTFOLIO OF MAJOR OIL RESERVOIRS IN THE PERMIAN BASIN: APPLICATION AND TRANSFER OF ADVANCED GEOLOGICAL AND ENGINEERING TECHNOLOGIES FOR INCREMENTAL PRODUCTION OPPORTUNITIES

    Energy Technology Data Exchange (ETDEWEB)

    Shirley P. Dutton; Eugene M. Kim; Ronald F. Broadhead; William Raatz; Cari Breton; Stephen C. Ruppel; Charles Kerans; Mark H. Holtz

    2003-04-01

    A play portfolio is being constructed for the Permian Basin in west Texas and southeast New Mexico, the largest petroleum-producing basin in the US. Approximately 1300 reservoirs in the Permian Basin have been identified as having cumulative production greater than 1 MMbbl of oil through 2000. Of these major reservoirs, approximately 1,000 are in Texas and 300 in New Mexico. On a preliminary basis, 32 geologic plays have been defined for Permian Basin oil reservoirs and assignment of each of the 1300 major reservoirs to a play has begun. The reservoirs are being mapped and compiled in a Geographic Information System (GIS) by play. Detailed studies of three reservoirs are in progress: Kelly-Snyder (SACROC unit) in the Pennsylvanian and Lower Permian Horseshoe Atoll Carbonate play, Fullerton in the Leonardian Restricted Platform Carbonate play, and Barnhart (Ellenburger) in the Ellenburger Selectively Dolomitized Ramp Carbonate play. For each of these detailed reservoir studies, technologies for further, economically viable exploitation are being investigated.

  18. Play Analysis and Digital Portfolio of Major Oil Reservoirs in the Permian Basin: Application and Transfer of Advanced Geological and Engineering Technologies for Incremental Production Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Shirley P. Dutton; Eugene M. Kim; Ronald F. Broadhead; Caroline L. Breton; William D. Raatz; Stephen C. Ruppel; Charles Kerans

    2004-01-13

    A play portfolio is being constructed for the Permian Basin in west Texas and southeast New Mexico, the largest onshore petroleum-producing basin in the United States. Approximately 1,300 reservoirs in the Permian Basin have been identified as having cumulative production greater than 1 MMbbl (1.59 x 10{sup 5} m{sup 3}) of oil through 2000. Of these significant-sized reservoirs, approximately 1,000 are in Texas and 300 in New Mexico. There are 32 geologic plays that have been defined for Permian Basin oil reservoirs, and each of the 1,300 major reservoirs was assigned to a play. The reservoirs were mapped and compiled in a Geographic Information System (GIS) by play. The final reservoir shapefile for each play contains the geographic location of each reservoir. Associated reservoir information within the linked data tables includes RRC reservoir number and district (Texas only), official field and reservoir name, year reservoir was discovered, depth to top of the reservoir, production in 2000, and cumulative production through 2000. Some tables also list subplays. Play boundaries were drawn for each play; the boundaries include areas where fields in that play occur but are smaller than 1 MMbbl (1.59 x 10{sup 5} m{sup 3}) of cumulative production. Oil production from the reservoirs in the Permian Basin having cumulative production of >1 MMbbl (1.59 x 10{sup 5} m{sup 3}) was 301.4 MMbbl (4.79 x 10{sup 7} m{sup 3}) in 2000. Cumulative Permian Basin production through 2000 was 28.9 Bbbl (4.59 x 10{sup 9} m{sup 3}). The top four plays in cumulative production are the Northwest Shelf San Andres Platform Carbonate play (3.97 Bbbl [6.31 x 10{sup 8} m{sup 3}]), the Leonard Restricted Platform Carbonate play (3.30 Bbbl [5.25 x 10{sup 8} m{sup 3}]), the Pennsylvanian and Lower Permian Horseshoe Atoll Carbonate play (2.70 Bbbl [4.29 x 10{sup 8} m{sup 3}]), and the San Andres Platform Carbonate play (2.15 Bbbl [3.42 x 10{sup 8} m{sup 3}]). Detailed studies of three reservoirs

  19. Characterization of the Photon Counting CHASE Jr., Chip Built in a 40-nm CMOS Process With a Charge Sharing Correction Algorithm Using a Collimated X-Ray Beam

    Energy Technology Data Exchange (ETDEWEB)

    Krzyżanowska, A. [AGH-UST, Cracow; Deptuch, G. W. [Fermilab; Maj, P. [AGH-UST, Cracow; Gryboś, P. [AGH-UST, Cracow; Szczygieł, R. [AGH-UST, Cracow

    2017-08-01

    This paper presents the detailed characterization of a single photon counting chip, named CHASE Jr., built in a CMOS 40-nm process, operating with synchrotron radiation. The chip utilizes an on-chip implementation of the C8P1 algorithm. The algorithm eliminates the charge sharing related uncertainties, namely, the dependence of the number of registered photons on the discriminator’s threshold, set for monochromatic irradiation, and errors in the assignment of an event to a certain pixel. The article presents a short description of the algorithm as well as the architecture of the CHASE Jr., chip. The analog and digital functionalities, allowing for proper operation of the C8P1 algorithm are described, namely, an offset correction for two discriminators independently, two-stage gain correction, and different operation modes of the digital blocks. The results of tests of the C8P1 operation are presented for the chip bump bonded to a silicon sensor and exposed to the 3.5- μm -wide pencil beam of 8-keV photons of synchrotron radiation. It was studied how sensitive the algorithm performance is to the chip settings, as well as the uniformity of parameters of the analog front-end blocks. Presented results prove that the C8P1 algorithm enables counting all photons hitting the detector in between readout channels and retrieving the actual photon energy.

  20. Real-time measurements of nitrogen oxide emissions from in-use New York City transit buses using a chase vehicle.

    Science.gov (United States)

    Shorter, Joanne H; Herndon, Scott; Zahniser, Mark S; Nelson, David D; Wormhoudt, Joda; Demerjian, Kenneth L; Kolb, Charles E

    2005-10-15

    New diesel engine technologies and alternative fuel engines are being introduced into fleets of mass transit buses to try to meet stricter emission regulations of nitrogen oxides and particulates: Real-time instruments including an Aerodyne Research tunable infrared laser differential absorption spectrometer (TILDAS) were deployed in a mobile laboratory to assess the impact of the implementation of the new technologies on nitrogen oxide emissions in real world driving conditions. Using a "chase" vehicle sampling strategy, the mobile laboratory followed target vehicles, repeatedly sampling their exhaust. Nitrogen oxides from approximately 170 in-use New York City mass transit buses were sampled during the field campaigns. Emissions from conventional diesel buses, diesel buses with continuously regenerating technology (CRT), diesel hybrid electric buses, and compressed natural gas (CNG) buses were compared. The chase vehicle sampling method yields real world emissions that can be included in more realistic emission inventories. The NO, emissions from the diesel and CNG buses were comparable. The hybrid electric buses had approximately one-half the NOx emissions. In CRT diesels, NO2 accounts for about one-third of the NOx emitted in the exhaust, while for non-CRT buses the NO2 fraction is less than 10%.

  1. OSQAR-CHASE Proposal

    CERN Document Server

    (Pugnat, P; (Sulc, M

    2015-01-01

    For 2015, the OSQAR collaboration will focus on a new proposal for the search of chameleon, a hypothetical scalar particle postulated as a dark energy candidate with an environment-dependant mass. The required experimental set-up has been successfully tested and validated in 2014 at the SM-18 experimental hall. This proposal will focus on the sensitivity that can be reached during the OSQAR chameleon run in 2015 as well as to possible upgrade phases of the experiment for the coming years.

  2. Chasing the Chinese Dream

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    People’s pursuit of better lives pushes the nation forward The belief that anyone can live a better life in the United States through hard workis called the American Dream. Many European settlers were drawn to the new continent by the American Dream.

  3. Chasing Unachievable Outcomes

    Science.gov (United States)

    Pangrazi, Robert P.

    2010-01-01

    Today, teachers complain about the lack of physical education time and the lack of physical education programming. In addition, a great deal of time is spent advocating the relationship between "healthy mind-healthy body." Today's drive to show a relationship between physical fitness/activity and academic achievement is really not different than…

  4. Chasing Ecological Interactions.

    Science.gov (United States)

    Jordano, Pedro

    2016-09-01

    Basic research on biodiversity has concentrated on individual species-naming new species, studying distribution patterns, and analyzing their evolutionary relationships. Yet biodiversity is more than a collection of individual species; it is the combination of biological entities and processes that support life on Earth. To understand biodiversity we must catalog it, but we must also assess the ways species interact with other species to provide functional support for the Tree of Life. Ecological interactions may be lost well before the species involved in those interactions go extinct; their ecological functions disappear even though they remain. Here, I address the challenges in studying the functional aspects of species interactions and how basic research is helping us address the fast-paced extinction of species due to human activities.

  5. Cutting to the chase

    International Nuclear Information System (INIS)

    Snieckus, D.

    2001-01-01

    This article reports on the development of the cost effective abrasive cutting Sabre system which came as a result of UWG's work on the decommissioning of the Phillips' Maureen wells and adds to UWG's 'total severance solution' tools. The advantages of the system are highlighted and include the ability to operate from a platform or diving support vessel, to cut internal cases, and to eliminate the use of environmentally damaging explosives and the need to operate from a rig. The new Mark II version of the Sabre designed to work at greater depths of water, the range of the severance tools, UWG's well abandonment hole assembly system, and its aim to enter the Gulf of Mexico market are discussed. Details are given of the decommissioning of the Schwedeneck-See platforms in Kiel Bay off Germany and the Phillips' UK decommissioning plans for the Maureen platform

  6. Chasing viruses feverishly

    Directory of Open Access Journals (Sweden)

    Chandrakant Lahariya

    2017-01-01

    Full Text Available A number of viral diseases have emerged and re-emerged in India and globally, in the last few years. Effective prevention and control of these diseases require, in addition to a functioning disease surveillance system, interventions both before and after disease occurrence, and a combination of personal and population services. However, the current efforts to control emerging viral diseases in India has major therapeutic focus (and attention on diagnostic and curative services and there is limited attention on preventive and promotive components. It is proposed that for an effective and successful control, a systematic approach is adopted with an appropriate selection of personal and population health services, delivered by government through participation of private sector. This is possible through commitment and leadership of Government and other public health agencies, supplemented by multi agency coordination, sufficient funding and an accountability mechanism.

  7. Chasing the Dream

    Science.gov (United States)

    Gardezi, Aleena

    2012-01-01

    Community colleges are gearing up to play a greater role in providing open access and affordable education to undocumented immigrants since President Barack Obama's re-election, which ensured the continuance of his June 15th executive order offering deferred deportation to eligible young immigrants. That order provided an opportunity for children…

  8. Salinity changes and anoxia resulting from enhanced run-off during the late Permian global warming and mass extinction event

    Science.gov (United States)

    van Soelen, Elsbeth E.; Twitchett, Richard J.; Kürschner, Wolfram M.

    2018-04-01

    The late Permian biotic crisis had a major impact on marine and terrestrial environments. Rising CO2 levels following Siberian Trap volcanic activity were likely responsible for expanding marine anoxia and elevated water temperatures. This study focuses on one of the stratigraphically most expanded Permian-Triassic records known, from Jameson Land, East Greenland. High-resolution sampling allows for a detailed reconstruction of the changing environmental conditions during the extinction event and the development of anoxic water conditions. Since very little is known about how salinity was affected during the extinction event, we especially focus on the aquatic palynomorphs and infer changes in salinity from changes in the assemblage and morphology. The start of the extinction event, here defined by a peak in spore : pollen, indicating disturbance and vegetation destruction in the terrestrial environment, postdates a negative excursion in the total organic carbon, but predates the development of anoxia in the basin. Based on the newest estimations for sedimentation rates, the marine and terrestrial ecosystem collapse took between 1.6 and 8 kyr, a much shorter interval than previously estimated. The palynofacies and palynomorph records show that the environmental changes can be explained by enhanced run-off and increased primary productivity and water column stratification. A lowering in salinity is supported by changes in the acritarch morphology. The length of the processes of the acritarchs becomes shorter during the extinction event and we propose that these changes are evidence for a reduction in salinity in the shallow marine setting of the study site. This inference is supported by changes in acritarch distribution, which suggest a change in palaeoenvironment from open marine conditions before the start of the extinction event to more nearshore conditions during and after the crisis. In a period of sea-level rise, such a reduction in salinity can only be

  9. Ca, Sr, Mo and U isotopes evidence ocean acidification and deoxygenation during the Late Permian mass extinction

    Science.gov (United States)

    Silva-Tamayo, Juan Carlos; Payne, Jon; Wignall, Paul; Newton, Rob; Eisenhauer, Anton; Weyer, Stenfan; Neubert, Nadja; Lau, Kim; Maher, Kate; Paytan, Adina; Lehrmann, Dan; Altiner, Demir; Yu, Meiyi

    2014-05-01

    The most catastrophic extinction event in the history of animal life occurred at the end of the Permian Period, ca. 252 Mya. Ocean acidification and global oceanic euxinia have each been proposed as causes of this biotic crisis, but the magnitude and timing of change in global ocean chemistry remains poorly constrained. Here we use multiple isotope systems - Ca, Sr, Mo and U - measured from well dated Upper Permian- Lower Triassic sedimentary sections to better constrain the magnitude and timing of change in ocean chemistry and the effects of ocean acidification and de-oxygenation through this interval. All the investigated carbonate successions (Turkey, Italy and China) exhibit decreasing δ44/40Ca compositions, from ~-1.4‰ to -2.0‰ in the interval preceding the main extinction. These values remain low during most of the Griesbachian, to finally return to -1.4‰ in the middle Dienerian. The limestone succession from southern Turkey also displays a major decrease in the δ88/86Sr values from 0.45‰ to 0.3‰ before the extinction. These values remain low during the Griesbachian and finally increase to 0.55‰ by the middle Dienerian. The paired negative anomalies on the carbonate δ44/40Ca and δ88/86Sr suggest a decrease in the carbonate precipitation and thus an episode of ocean acidification coincident with the major biotic crisis. The Mo and U isotope records also exhibit significant rapid negative anomalies at the onset of the main extinction interval, suggesting rapid expansion of anoxic and euxinic marine bottom waters during the extinction interval. The rapidity of the isotope excursions in Mo and U suggests substantially reduced residence times of these elements in seawater relative to the modern, consistent with expectations for a time of widespread anoxia. The large C-isotope variability within Lower Triassic rocks, which is similar to that of the Lower-Middle Cambrian, may reflect biologically controlled perturbations of the oceanic carbon cycle

  10. Lower Permian stems as fluvial paleocurrent indicators of the Parnaíba Basin, northern Brazil

    Science.gov (United States)

    Capretz, Robson Louiz; Rohn, Rosemarie

    2013-08-01

    A comprehensive biostratinomic study was carried out with abundant stems from the Lower Permian Motuca Formation of the intracratonic Parnaíba Basin, central-north Brazil. The fossils represent a rare tropical to subtropical paleofloristic record in north Gondwana. Tree ferns dominate the assemblages (mainly Tietea, secondarily Psaronius), followed by gymnosperms, sphenophytes, other ferns and rare lycophytes. They are silica-permineralized, commonly reach 4 m length (exceptionally more than 10 m), lie loosely on the ground or are embedded in the original sandstone or siltstone matrix, and attract particular attention because of their frequent parallel attitudes. Many tree fern stems present the original straight cylindrical to slightly conical forms, other are somewhat flattened, and the gymnosperm stems are usually more irregular. Measurements of stem orientations and dimensions were made in three sites approximately aligned in a W-E direction in a distance of 27.3 km at the conservation unit "Tocantins Fossil Trees Natural Monument". In the eastern site, rose diagrams for 54 stems indicate a relatively narrow azimuthal range to SE. These stems commonly present attached basal bulbous root mantles and thin cylindrical sandstone envelopes, which sometimes hold, almost adjacent to the lateral stem surface, permineralized fern pinnae and other small plant fragments. In the more central site, 82 measured stems are preferentially oriented in the SW-NE direction, the proportion of gymnosperms is higher and cross-stratification sets of sandstones indicate paleocurrents mainly to NE and secondarily to SE. In the western site, most of the 42 measured stems lie in E-W positions. The predominantly sandy succession, where the fossil stems are best represented, evidences a braided fluvial system under semiarid conditions. The low plant diversity, some xeromorphic features and the supposedly almost syndepositional silica impregnation of the plants are coherent with marked dry

  11. Chemical signature of two Permian volcanic ash deposits within a bentonite bed from Melo, Uruguay

    Directory of Open Access Journals (Sweden)

    Liane M. Calarge

    2006-09-01

    Full Text Available A Permian bentonite deposit at Melo, Uruguay is composed of a calcite-cemented sandstone containing clay pseudomorphs of glass shards (0-0.50 m overlying a pink massive clay deposit (0.50-2.10m. The massive bed is composed of two layers containing quartz and smectite or pure smectite respectively. The smectite is remarkably homogeneous throughout the profile: it is a complex mixed layer composed of three layer types whose expandability with ethylene glycol (2EG 1EG or 0EG sheets in the interlayer zone which correspond to low-, medium- and high-charge layers respectively varies with the cation saturating the interlayer zone. The smectite homogeneity through the profile is the signature of an early alteration process in a lagoonal water which was over saturated with respect to calcite. Compaction during burial has made the bentonite bed a K-depleted closed system in which diagenetic illitization was inhibited. Variations in major, REE and minor element abundances throughout the massive clay deposit suggest that it originated from two successive ash falls. The incompatible element abundances are consistent with that of a volcanic glass fractionated from a rhyolite magma formed in a subduction/collision geological context.Um depósito Permiano de bentonita em Melo, Uruguai,é composto por um arenito com cimento calcítico contendo pseudomorfos de argila sobre detritos vítreos(0-0.50 m superpostos a um deposito maciço de argila rosado (0.50-2.10 m. A camada maciça é composta por dois níveis contendo quartzo e esmectita ou esmectita pura, respectivamente. A homogeneidade de esmectita ao longo do perfil é notável: trata-se de um interestratificado composto de três tipos de camadas, cuja expansibilidade com etileno-glicol (folhas 2EG, 1EG ou 0EG na zona interfoliar correspondentes a camadas com baixa, média e alta carga, respectivamente variam com o tipo de cátion que satura a zona interfoliar. A homogeneidade da esmectita ao longo do perfil

  12. The Upper Permian sandstones of Mountains Mecsek: form elements of uranium ore mineralization and facies relations Pt. 2

    International Nuclear Information System (INIS)

    Vincze, Janos; Somogyi, Janos

    1984-01-01

    The ore mineralization in the Upper Permian sandstones of Mountais Mecsek, Hungary, was brought about at the oxidation-reduction front between the grey and red sandstones; the predominant rock colour here is green. The sandstones of different colour are oxidation-reduction species. The formation is a megacycle containing in its core grey sandstones of reduced state with coalified plant remains and in its mantle oxidized red sandstones. Uranium accumulates mainly in the transitional green facies. Uranium content gets enriched to a commercial concentration only if the difference in potential of neighbouring beds is in the range of 400-480 mV. The relationship between organic matter and uranium content in the individual facies is shown. The principles of oxidation-reduction processes in the formation of boundary facies are discussed. (V.N.)

  13. A new captorhinid reptile from the Lower Permian of Oklahoma showing remarkable dental and mandibular convergence with microsaurian tetrapods

    Science.gov (United States)

    Reisz, R. R.; LeBlanc, Aaron R. H.; Sidor, Christian A.; Scott, Diane; May, William

    2015-10-01

    The Lower Permian fossiliferous infills of the Dolese Brothers Limestone Quarry, near Richards Spur, Oklahoma, have preserved the most diverse assemblage of Paleozoic terrestrial vertebrates, including small-bodied reptiles and lepospondyl anamniotes. Many of these taxa were previously known only from fragmentary remains, predominantly dentigerous jaw elements and numerous isolated skeletal elements. The recent discovery of articulated skulls and skeletons of small reptiles permits the recognition that dentigerous elements, previously assigned at this locality to the anamniote lepospondyl Euryodus primus, belong to a new captorhinid eureptile, Opisthodontosaurus carrolli gen. et sp. nov. This mistaken identity points to a dramatic level of convergence in mandibular and dental anatomy in two distantly related and disparate clades of terrestrial tetrapods and sheds light on the earliest instance of durophagy in eureptiles.

  14. On the Geological Age of the Sundyr Faunal Assemblage of Permian Tetrapods from the East European Platform

    Directory of Open Access Journals (Sweden)

    Golubev V.K.

    2015-03-01

    Full Text Available A new Sundyr faunal assemblage of Permian tetrapods was discovered in Eastern Europe. It includes dinocephalians Titanosuchia fam. indet., tapinocephalians aff. Ulemosauridae, anomodontians aff. Suminia, therocephalians, gorgonopians Burnetioidea fam. indet., diapsids ? Eosuchia, chroniosuchians Suchonica vladimiri Golubev, enosuchids aff. Enosuchus, seymouriamorphs Microphon exiguus Ivachnenko and Leptoropha aff. talonophora, batrachomorphs Dvinosaurus sp. The Sundyr assemblage is a transitional one from the Isheevo to Sokolki assemblages. It is described as the last stage of evolution undergone by the dinocephalian community of tetrapods in Eastern Europe. Based on the bio- and magnetostratigraphic data, the beds with Sundyr tetrapod fauna pertain to the lower part of the Upper Severodvinian (= Putyatinian regional stage. These strata were distinguished into a new Suchonica vladimiri tetrapod assemblage zone. In the Sukhona River basin, the beds with Sundyr tetrapod fossils were distinguished into a new Ustpoldarsa Member of the Poldarsa Formation.

  15. Regulatory Project Manager for Salina and Permian Basins for the NWTS [National Waste Terminal Storage] Program: Final techical report

    International Nuclear Information System (INIS)

    1986-12-01

    The identification of candidate sites for nuclear waste repositories involves geological and environmental studies to characterize potential sites. These investigations include the collection and analysis of detailed geological and environmental data and comparison of the data against predetermined site performance criteria, i.e., geologic characteristics, environmental protection, and socioeconomic impacts. The work summarized in this final technical report encompasses mainly ''environmental characterization'' studies in the Permian Basin in the Texas Panhandle during the period of 1977-86; in the earlier phase of the contract, regional environmental work was also done in the Salina Basin (1977-79) and certain licensing support activities and safety analyses were conducted (1977-82). Considerable regulatory support work was also performed during 1986. 9 figs., 2 tabs

  16. Bone microstructures and mode of skeletogenesis in osteoderms of three pareiasaur taxa from the Permian of South Africa.

    Science.gov (United States)

    Scheyer, T M; Sander, P M

    2009-06-01

    The extinct parareptilian clade of pareiasaurs was in the past often presented to constitute a morphocline from larger, less armoured forms to smaller, well armoured forms, indicating that the osteoderm cover became an increasingly prominent aspect in the post-cranial skeleton of these animals. Here, we describe microanatomical and microstructural aspects of osteoderms of the three pareiasaur taxa Bradysaurus, Pareiasaurus and Anthodon from the Permian of South Africa. A generalized mode of osteoderm formation, consistent with intramembraneous skeletogenesis, is hypothesized to be present in all pareiasaurs. Few characters are shared between pareiasaur dermal armour and turtle shell bones and osteoderms. Otherwise, there is strong evidence from microanatomy and histology (i.e. absence of structures that formed via metaplasia of dermal tissue) that indicates nonhomology between pareiasaur dermal armour and the armour of living eureptiles. Analysis with bone profiler revealed no clear connection between bone compactness and lifestyle in the amniote osteoderm sample.

  17. Tracing carbon flow from microphytobenthos to major bacterial groups in an intertidal marine sediment by using an in situ 13C pulse-chase method

    OpenAIRE

    Miyatake, T.; Moerdijk-Poortvliet, T.C.W.; Stal, L.J.; Boschker, H.T.S.

    2014-01-01

    Carbon flow from benthic diatoms to heterotrophic bacterial was traced in an intertidal sediment for 5 consecutive days. 13C-labeled bicarbonate was sprayed onto the sediment surface during low tide and 13C-label incorporation in major carbon pools, intermediate metabolites, and biomarkers were monitored. Phospholipid-derived fatty acid (PLFA) and ribosomal ribonucleic acid (rRNA) were used to identify the responsible members of the microbial community at class and family phylogenetic resolut...

  18. Tracing carbon flow from microphytobenthos to major bacterial groups in an intertidal marine sediment by using an in situ 13C pulse-chase method

    NARCIS (Netherlands)

    Miyatake, T.; Moerdijk-Poortvliet, T.C.W.; Stal, L.J.; Boschker, H.T.S.

    2014-01-01

    Carbon flow from benthic diatoms to heterotrophic bacterial was traced in an intertidal sediment for 5 consecutive days. 13C-labeled bicarbonate was sprayed onto the sediment surface during low tide and 13C-label incorporation in major carbon pools, intermediate metabolites, and biomarkers were

  19. Molecular Evidence for Radical Changes in Ocean Chemistry Across the Permian Triassic Boundary at Meishan in South China

    Science.gov (United States)

    Love, G. D.; Cao, C.; Jin, Y.; Summons, R. E.

    2004-12-01

    Samples from outcrop and from a new core drilled through the Permian Triassic Boundary at the type section at Meishan have been examined for biomarker and isotopic evidence of biotic and associated environmental change. Late Permian sediments from Meishan Beds 22-27 are characterized by indicators of anoxia including low Pr/Ph ratios and abundant aryl isoprenoids and isoreneieratane derived from the precursor carotenoid isorenieratene. The latter compounds are biomarkers for green sulfur bacteria (Chlorobiaceae) and are considered reliable indicators of euxinic water columns where sulfide extends to the photic zone. The peak of Chlorobiaceae biomarker abundance coincides with a rapid and synchronous drop in the ƒO13C and ƒO15N values of kerogen. On passing up into the Early Triassic, the biomarker signal for Chlorobiaceae wanes and is almost absent by Bed 30 where it is replaced by one for cyanobacteria including abundant hopanes and 2-methylhopanes and accompanying methyl and dimethyl alkanes. A very high value for the hopane/sterane ratio from Beds 30-38 indicates continuing dominant cyanobacterial productivity and only minor inputs from an algal plankton. The prevalence of aryl isoprenoids in P-Tr sediments at the Meishan section of South China is also recorded in a recently cored borehole, Hovea-3, of the Perth Basin, Western Australia. This suggests similar paleoenvironmental conditions prevailed across the Tethys Ocean during and immediately after the P-Tr Boundary. In particular, the presence of biomarkers for Chlorobiaceae at two separate locations indicates that water column euxinia was pervasive during the extinction event and suggests that sulfide may have been a key toxic agent.

  20. The salt that wasn't there: Mudflat facies equivalents to halite of the Permian Rustler Formation, southeastern New Mexico

    International Nuclear Information System (INIS)

    Powers, D.W.; Holt, R.M.

    2000-01-01

    Four halite beds of the Permian Restler Formation in southeastern New Mexico thin dramatically over horst lateral distances to correlative classic (mudstone) beds. The mudstones have long been considered residues after post-burial dissolution (subrosion) of halite, assumed to have been deposited continuously across the area. Hydraulic properties of the Culebra Dolomite Member have often been related to Rustler subrosion. In cores and three shafts at the Waste Isolation Pilot Plant (WIPP), however, these mudstones display flat bedding, graded bedding, cross-bedding, erosional contacts, and channels filled with intraformational conglomerates. Cutans indicate early stages of soil development during subaerial exposure. Smeared intraclasts developed locally as halite was removed syndepositionally during subaerial exposure. The authors interpret these beds as facies formed in salt-pan or hypersaline-lagoon, transitional, and mudflat environments. Halite is distributed approximately as it was deposited. Breccia in limited areas along one halite margin indicates post-burial dissolution, and these breccials are key to identifying areas of subrosion. A depositional model accounts for observed sedimentary features of Restler mudstones. Marked facies and thickness changes are consistent with influence by subsidence boundaries, as found in some modern continental evaporites. A subrosion model accounts for limited brecciated zones along (depositional)halite margins, but bedding observed in the mudstones would not survive 90% reduction in rock volume. Depositional margins for these halite beds will be useful in reconstructing detailed subsidence history of the Late Permian in the northern Delaware Basin, It also no longer is tenable to attribute large variations in Culebra transmissivity to Rustler subrosion

  1. Carbon isotope evidence for a vigorous biological pump in the wake of end-Permian mass extinction

    Science.gov (United States)

    Meyer, K. M.; Yu, M.; Jost, A. B.; Payne, J.

    2009-12-01

    Ocean anoxia and euxinia have long been linked to the end-Permian mass extinction and the subsequent Early Triassic interval of delayed biotic recovery. This anoxic, sulfidic episode has been ascribed to both low- and high-productivity states in the marine water column, leaving the causes of euxinia and the mechanisms underlying delayed recovery poorly understood. To examine the nature of the end-Permian and Early Triassic biological production, we measured the carbon isotopic composition of carbonates from an exceptionally preserved carbonate platform in the Nanpanjiang Basin of south China. 13C of limestones from 5 stratigraphic sections displays a gradient of approximately 4‰ from shallow to deep water within the Lower Triassic. The limestones are systematically enriched in the platform interior relative to coeval slope and basin margin deposits by 2-4‰ at the peaks of correlative positive and negative δ13C excursions. This gradient subsequently collapses to less than 1‰ in the Middle Triassic, coincident with accelerated biotic recovery and cessation of δ13C excursions. Based on the relationship between δ18O and δ13C, trace metal analyses, and lithostratigraphic context, we conclude that the carbon isotope gradient is unlikely to reflect meteoric diagenesis, organic matter remineralization, or changes in the mixing ratio of sediment sources and minerals across the platform. Instead, we interpret the relatively depleted δ13C values toward the basin as reflecting DIC input from 13C-depleted deep waters during early diagenesis in a nutrient-rich, euxinic ocean. These observations suggest that a vigorous prokaryote-driven biological pump sustained Early Triassic ocean anoxia and inhibited recovery of animal ecosystems.

  2. Precession-driven monsoon variability at the Permian-Triassic boundary — Implications for anoxia and the mass extinction

    Science.gov (United States)

    Winguth, Arne; Winguth, Cornelia

    2013-06-01

    By the end of the Late Permian, most continents had collided to form the supercontinent of Pangea. The associated climatic changes at the Permian-Triassic boundary coincided with the most severe mass extinction in the Phanerozoic. One extinction hypothesis favors a climatic response to an increase in large-scale volcanism resulting in ocean stagnation and widespread anoxia with fatal consequences for marine and land organisms. Recent interpretations of geochemical data suggest that orbitally-driven periodic upwelling of toxic hydrogen-sulfide rich water masses contributed to the extinction of species. In this paper, we use the Community Climate System Model (CCSM3) in order to explore the effect of eccentricity-modulated changes of the precession on the strength of Pangean megamonsoons and their impact on productivity and oxygen distribution. The climate model simulates high variability in monsoonal precipitation, trade winds and equatorial upwelling in response to precessional extremes, leading to remarkable fluctuations in the export of carbon from the euphotic zone and hence reduction in dissolved oxygen concentrations in subsurface layers. These findings are in general agreement with increased primary productivity, intensified euxinia within the oxygen-minimum zone, and decimation of the radiolarian zooplankton community as inferred from Japanese marine sections. Strong changes in river run-off linked to precipitation oscillations possibly led to a high variability in the nutrient supply to the Tethys Ocean, thus affecting regional productivity and oxygen distribution. The model results suggest that orbital variability in the sedimentary record and the associated extinction of species are related rather to periodic anoxia in near surface-to-intermediate depth than to widespread anoxic events in the Panthalassic deep-sea.

  3. A Review on Permian to Triassic Active or Convergent Margin in Southeasternmost Gondwanaland: Possibility of Exploration Target for Tin and Hydrocarbon Deposits in the Eastern Indonesia

    Directory of Open Access Journals (Sweden)

    Amiruddin Amiruddin

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol4no1.20094An active convergence of continental margin is probably generated in Gondwanaland during Permian to Triassic period which is characterized by the presence of magmatic and volcanic belts and back-arc ba- sins occupied respectively by Permian to Triassic rocks. The magmatic belt is occupied by peraluminous granitic plutons showing characteristics of S- type granite and is considered as tin-bearing granites. The back-arc basins are occupied by the Southern Papua and Galille-Bowen-Gunnedah-Sydney Basins. Those large basins are respectivelly filled by fluvial, fluvio- deltaic to marine Permian-Triassic sediments, which are unconformably overlain by the Jurrassic-Cretaceous marine succession. The paleomagnetic data, confirmed by flora content found in Australia and Papua, indicate that those areas initially belong to the Gondwanaland before part of them were drifted and rotated into the present day position. Tectonically, the presence of those Permian-Triassic magmatic-volcanic belts and back-arc basins in behind, indicates that at the time there were huge compressive activities: convergence of paleo-oceanic Pasific Plate moving westward, collided and subducted into the Southeastern Gondwana Continental Plate, moved relatively eastwards. This phenomenon resembles to the formation of Sumatera Tertiary tectonic zones producing back-arc basins, i.e. South Sumatera, Central, and North Sumatera Basins including the Tertiary Magmatic Arc. Concerning the similarity of Permian-Triassic geological condition of the magmatic arc and back-arc basins in Eastern Indonesia and Eastern Australia including paleoposition, paleotectonic setting, strati- graphic succession, and lithologic composition, it is suggested to carry out an increase in a more intens- ive tin exploration in the Eastern Indonesia, e.g. Bird Head area and Banggai Sula Island, and also for hydrocarbon target (coal, coalbed methane, oil and gas, and oil

  4. Isotope geochemistry of fluid inclusions in Permian halite with implications for the isotopic history of ocean water and the origin of saline formation waters

    International Nuclear Information System (INIS)

    Knauth, L.P.; Beeunas, M.A.

    1986-01-01

    deltaD and delta 18 O values have been determined for fluid inclusions in 45 samples of Permian halite. The inclusions are enriched in 18 O relative to the meteoric water line but are depleted in D relative to ocean water. Inclusions with the more positive delta-values coincide with the isotopic compositions expected for evaporating sea water which follows a hooked trajectory on a deltaD-delta 18 O diagram. Inclusions with more negative delta-values may represent more highly evaporated sea water but probably reflect synsedimentary or diagenetic mixing to those of a modern evaporite pan to indicate that Permian sea water was isotopically similar to modern sea water. Connate evaporite brines can have negative delta-values because of the probable hooked isotope trajectory of evaporating sea water and/or synsedimentary mixing of evaporite brines with meteoric waters. (author)

  5. Permian-Triassic maturation and multistage migration of hydrocarbons in the Assistência Formation (Irati Subgroup, Paraná Basin, Brazil: implications for the exploration model

    Directory of Open Access Journals (Sweden)

    António Mateus

    Full Text Available New lines of geological evidence strongly suggest that the main period of hydrocarbon maturation within Assistência Formation should be Permian-Triassic, stimulated by a high geothermal gradient that also sustained various manifestations of hydrothermal activity. Three main stages of fluid/hydrocarbon migration can also be inferred on the basis of multiscale observations: confined flow in late Permian to Triassic times, depending on the local build-up of fluid pressures; heterogeneous flow in Lower Cretaceous, triggered by a rejuvenated temperature gradient assisted by the early developed permeability conditions; and a late flow possibly driven by local pressure gradients, after complete cooling of dolerite dykes/sills. The early maturation and multistage migration of hydrocarbons have significant consequences in the design of exploration models to be applied in Paraná Basin.

  6. Permian A-type rhyolites of the Muráň Nappe, Inner Western Carpathians, Slovakia: in-situ zircon U-Pb SIMS ages and tectonic setting

    Science.gov (United States)

    Ondrejka, Martin; Li, Xian-Hua; Vojtko, Rastislav; Putis, Marian; Uher, Pavel; Sobocký, Tomas

    2018-04-01

    Three representative A-type rhyolitic rock samples from the Muráň Nappe of the inferred Silicic Unit of the Inner Western Carpathians (Slovakia) were dated using the high-precision SIMS U-Pb isotope technique on zircons. The geochronological data presented in this paper is the first in-situ isotopic dating of these volcanic rocks. Oscillatory zoned zircon crystals mostly revealed concordant Permian (Guadalupian) ages: 266.6 ± 2.4 Ma in Tisovec-Rejkovo (TIS-1), 263.3 ± 1.9 Ma in Telgárt-Gregová Hill (TEL-1) and 269.5 ± 1.8 Ma in Veľká Stožka-Dudlavka (SD-2) rhyolites. The results indicate that the formation of A-type rhyolites and their plutonic equivalents are connected to magmatic activity during the Permian extensional tectonics and most likely related to the Pangea supercontinent break-up.

  7. Pumping test and fluid sampling report, Mansfield No. 1 well, Palo Duro Basin: Report of the Geologic Project Manager, Permian Basin

    Energy Technology Data Exchange (ETDEWEB)

    1983-07-01

    This report describes pumping test and fluid sampling activities performed at the Mansfield No. 1 well in Oldham County about 10 miles north of Vega, Texas. The well site was selected by TBEG and is located along the northern margin of the Palo Duro Basin in an area of active dissolution with the Permian salt sections. The objectives of the pumping test and fluid sampling program were to collect data to determine the hydrologic characteristics (formation pressure and permeability) of deep water bearing formations, and to obtain formation fluid samples for analyses (gas and fluid chemistry) in order to evaluate fluid migration and age relationships in the Permian Basin. 4 refs., 8 figs., 2 tabs.

  8. Pumping test and fluid sampling report, Mansfield No. 1 well, Palo Duro Basin: Report of the Geologic Project Manager, Permian Basin

    International Nuclear Information System (INIS)

    1983-07-01

    This report describes pumping test and fluid sampling activities performed at the Mansfield No. 1 well in Oldham County about 10 miles north of Vega, Texas. The well site was selected by TBEG and is located along the northern margin of the Palo Duro Basin in an area of active dissolution with the Permian salt sections. The objectives of the pumping test and fluid sampling program were to collect data to determine the hydrologic characteristics (formation pressure and permeability) of deep water bearing formations, and to obtain formation fluid samples for analyses (gas and fluid chemistry) in order to evaluate fluid migration and age relationships in the Permian Basin. 4 refs., 8 figs., 2 tabs

  9. Record of Permian-Early Triassic continental arc magmatism in the western margin of the Jiamusi Block, NE China: petrogenesis and implications for Paleo-Pacific subduction

    Science.gov (United States)

    Yang, Hao; Ge, Wenchun; Dong, Yu; Bi, Junhui; Wang, Zhihui; Ji, Zheng; Yang, H.; Ge, W. C.; Dong, Y.; Bi, J. H.; Wang, Z. H.; Ji, Z.

    2017-09-01

    In this paper, we report zircon U-Pb ages, Hf isotopes and whole-rock geochemical data for the Permian to Early Triassic granitoids from the western margin of the Jiamusi Block (WJB), NE China. The intermediate to felsic (SiO2 = 59.67-74.04 wt%) granitoids belong to calc-alkaline series and are characterized by enrichments in light rare earth elements and large ion lithophile elements with pronounced negative Nb, Ta and Ti anomalies, revealing typical continental magmatic arc geochemical signatures. The zircon U-Pb determinations on the granodiorite, monzogranite, syenogranite and quartz diorite samples yielded ages between ca. 275-245 Ma, which, together with the published coeval intrusive rocks, indicates that Permian to Early Triassic continental arc magmatism occurred extensively in the WJB. The low and mainly negative zircon ɛ Hf( t) values between -7.6 and +1.6 and the zircon Hf model ages of 1.2-1.8 Ga, which are significantly older than their crystallization ages, suggest that they were mainly derived from reworking of ancient crustal materials with a limited input of juvenile components. The geochemical systematics and petrogenetic considerations indicate that the studied granitoids were generated from a zone of melting, assimilation, storage, and homogenization, i.e., a MASHed zone at the base of Paleo- to Mesoproterozoic continental crust, where large portions of igneous rocks and minor clay-poor sediments involved in the source region. In combination with regional geological data, we argue that the Jiamusi Block was unlikely the rifted segment of the Songliao Block and two possible geodynamical models were proposed to interpret the formation of the ca. 275-245 Ma granitoids in the WJB. In the context of Permian global plate reconstruction, we suggest that Paleo-Pacific plate subduction was initiated in the Permian to Early Triassic beneath the Jiamusi Block, and even whole eastern NE China.

  10. Paleosols of the upper Paleozoic Sangre de Cristo Formation, north-central New Mexico: Record of early Permian palaeoclimate in tropical Pangaea

    Directory of Open Access Journals (Sweden)

    Lawrence H. Tanner

    2017-04-01

    During the early Permian, northern New Mexico was situated in a near equatorial position (ca. 4° N. The overall character of the paleosols suggests a persistent warm, semi-humid, seasonal climate throughout most of the interval of deposition during the Wolfcampian, but with episodically increased aridity during formation of the more mature calcretes. No long-term trend of climate change is evident in the stratigraphic section examined for this study.

  11. Geochemistry of formation waters from the Wolfcamp and “Cline” shales: Insights into brine origin, reservoir connectivity, and fluid flow in the Permian Basin, USA

    Science.gov (United States)

    Engle, Mark A.; Reyes, Francisco R.; Varonka, Matthew S.; Orem, William H.; Lin, Ma; Ianno, Adam J.; Westphal, Tiffani M.; Xu, Pei; Carroll, Kenneth C.

    2016-01-01

    Despite being one of the most important oil producing provinces in the United States, information on basinal hydrogeology and fluid flow in the Permian Basin of Texas and New Mexico is lacking. The source and geochemistry of brines from the basin were investigated (Ordovician- to Guadalupian-age reservoirs) by combining previously published data from conventional reservoirs with geochemical results for 39 new produced water samples, with a focus on those from shales. Salinity of the Ca–Cl-type brines in the basin generally increases with depth reaching a maximum in Devonian (median = 154 g/L) reservoirs, followed by decreases in salinity in the Silurian (median = 77 g/L) and Ordovician (median = 70 g/L) reservoirs. Isotopic data for B, O, H, and Sr and ion chemistry indicate three major types of water. Lower salinity fluids (100 g/L), isotopically heavy (O and H) water in Leonardian [Permian] to Pennsylvanian reservoirs (2–3.2 km depth) is evaporated, Late Permian seawater. Water from the Permian Wolfcamp and Pennsylvanian “Cline” shales, which are isotopically similar but lower in salinity and enriched in alkalis, appear to have developed their composition due to post-illitization diffusion into the shales. Samples from the “Cline” shale are further enriched with NH4, Br, I and isotopically light B, sourced from the breakdown of marine kerogen in the unit. Lower salinity waters (3 km depth), which plot near the modern local meteoric water line, are distinct from the water in overlying reservoirs. We propose that these deep meteoric waters are part of a newly identified hydrogeologic unit: the Deep Basin Meteoric Aquifer System. Chemical, isotopic, and pressure data suggest that despite over-pressuring in the Wolfcamp shale, there is little potential for vertical fluid migration to the surface environment via natural conduits.

  12. Origin, distribution, and movement of brine in the Permian Basin (U.S.A.). A model for displacement of connate brine

    International Nuclear Information System (INIS)

    Bein, A.; Dutton, A.R.

    1993-01-01

    Na-Cl, halite Ca-Cl, and gypsum Ca-Cl brines with salinities from 45 to >300 g/L are identified and mapped in four hydrostratigraphic units in the Permian Basin area beneath western Texas and Oklahoma and eastern New Mexico, providing spatial and lithologic constraints on the interpretation of the origin and movement of brine. Na-Cl brine is derived from meteoric water as young as 5-10 Ma that dissolved anhydrite and halite, whereas Ca-Cl brine is interpreted to be ancient, modified-connate Permian brine that now is mixing with, and being displaced by, the Na-Cl brine. Displacement fronts appear as broad mixing zones with no significant salinity gradients. Evolution of Ca-Cl brine composition from ideal evaporated sea water is attributed to dolomitization and syndepositional recycling of halite and bittern salts by intermittent influx of fresh water and sea water. Halite Ca-Cl brine in the evaporite section in the northern part of the basin differs from gypsum Ca-Cl brine in the south-central part in salinity and Na/Cl ratio and reflects segregation between halite- and gypsum-precipitating lagoons during the Permian. Ca-Cl brine moved downward through the evaporite section into the underlying Lower Permian and Pennsylvanian marine section that is now the deep-basin brine aquifer, mixing there with pre-existing sea water. Buoyancy-driven convection of brine dominated local flow for most of basin history, with regional advection governed by topographically related forces dominant only for the past 5 to 10 Ma. 71 refs., 11 figs

  13. Late Carboniferous to early Permian sedimentary–tectonic evolution of the north of Alxa, Inner Mongolia, China: Evidence from the Amushan Formation

    Directory of Open Access Journals (Sweden)

    Haiquan Yin

    2016-09-01

    Full Text Available The late Paleozoic evolution of the Wulijishanhen (WSH-Shangdan (SD area near to the Chaganchulu Ophiolite belt is reinterpreted. Analysis of the upper Carboniferous to lower Permian sedimentary sequence, biological associations, detrital materials, sandstone geochemistry and volcanic rocks indicates that the SD area was an epicontinental sea and rift during the late Paleozoic rather than a large-scale ocean undergoing spreading and closure. This study reveals that the actual evolution of the study area is from the late Carboniferous to the early Permian. The fusulinids Triticites sp. and Pseudoschwagerina sp. in the limestones demonstrate that the Amushan Formation develops during the late Carboniferous to the early Permian. The limestones at the base of the SD section indicate that it is a stable carbonate platform environment, the volcanic rocks in the middle of the sequence support a rift tectonic background, and the overlying conglomerates and sandstones are characteristic of an epicontinental sea or marine molasse setting. The rift volcanism made the differences in the fossil content of the SD and WSH sections and led to two sections expose different levels within the Amushan Formation and different process of tectonic evolution. Moreover, the geochemical characteristics and detrital materials of the sandstones show that the provenance and formation of the sandstones were related to the setting of active continental margin. The quartz-feldspar-lithic fragments distribution diagram indicates that the material source for the sandstones was a recycled orogenic belt. Thus, the source area of the sandstones may have been an active continental margin before the late Carboniferous–early Permian. The characteristics of the regional tectonic evolution of the area indicate that the region may form a small part of the Gobi–Tianshan rift of southern Mongolia.

  14. Australian provenance for Upper Permian to Cretaceous rocks forming accretionary complexes on the New Zealand sector of the Gondwana land margin

    International Nuclear Information System (INIS)

    Pickard, A.L.; Barley, M.E.

    2000-01-01

    U-Pb (SHRIMP) detrital zircon age patterns are reported for 12 samples of Permian to Cretaceous turbiditic quartzo-feldspathic sandstone from the Torlesse and Waipapa suspect terranes of New Zealand. Their major Permian to Triassic, and minor Early Palaeozoic and Mesoproterozoic, age components indicate that most sediment was probably derived from the Carboniferous to Triassic New England Orogen in northeastern Australia. Rapid deposition of voluminous Torlesse/Waipapa turbidite fans during the Late Permian to Late Triassic appears to have been directly linked to uplift and exhumation of the magmatically active orogen during the 265-230 Ma Hunter-Bowen event. This period of cordilleran-type orogeny allowed transport of large volumes of quartzo-feldspathic sediment across the convergent Gondwana land margin. Post-Triassic depocentres also received (recycled?) sediment from the relict orogen as well as from Jurassic and Cretaceous volcanic provinces now offshore from southern Queensland and northern New South Wales. The detailed provenance-age fingerprints provided by the detrital zircon data are also consistent with progressive southward derivation of sediment: from northeastern Queensland during the Permian, southeastern Queensland during the Triassic, and northeastern New South Wales - Lord Howe Rise - Norfolk Ridge during the Jurassic to Cretaceous. Although the dextral sense of displacement is consistent with the tectonic regime during this period, detailed characterisation of source terranes at this scale is hindered by the scarcity of published zircon age data for igneous and sedimentary rocks in Queensland and northern New South Wales. Mesoproterozoic and Neoproterozoic age components cannot be adequately matched with likely source terranes in the Australian-Antarctic Precambrian craton, and it is possible they originated in the Proterozoic cores of the Cathaysia and Yangtze Blocks of southeast China. Copyright (1999) Geological Society of Australia

  15. A sedimentological analysis of sediments corresponding to the San Gregorio Formation )Lower Permian), located in the eastern border of the North Uruguayan Basin, Sierra Guazunambi

    International Nuclear Information System (INIS)

    Goso Aguilar, C.; Gama, E.

    1998-01-01

    A sedimentological analysis of sediments corresponding to the San Gregorio Formation (Lower Permian), located in the eastern border of the Norte Uruguayan Basin, Sierra Guazunambi, Cerro Largo Departament was made. Facies analysis of about 100 otucrops fand more than 1.300 meters, in an area of 45 square kilometers showed diamictites rhytmites and massive sandstones, formed by gravitational sedimentary flows. Also present are prodelta mudrocks and deltaic front sandstones.(author)

  16. Two-phase southward subduction of the Mongol-Okhotsk oceanic plate constrained by Permian-Jurassic granitoids in the Erguna and Xing'an massifs (NE China)

    Science.gov (United States)

    Liu, Huichuan; Li, Yinglei; He, Hongyun; Huangfu, Pengpeng; Liu, Yongzheng

    2018-04-01

    Geodynamics of the Mongol-Okhotsk oceanic plate southward subduction are still pending problems. This paper presents new zircon LA-ICP-MS U-Pb age and whole-rock geochemical data for the middle Permian to Middle Jurassic granitoids in the western Erguna and central Xing'an massifs. 267-264 Ma, 241 Ma and 173 Ma I-type granites, and 216 Ma A-type granites were identified in the Erguna and Xing'an massifs (NE China). The I-type granites were produced by partial melting of the lower mafic crust. The 216 Ma A-type granites were derived from partial melting of crustal materials with tonalitic to granodioritic compositions. The 267-264 Ma and 241 Ma I-type granites were generated in an Andean-type arc setting, wheras the 216 Ma A-type and 173 Ma granites were formed in supra subduction extensional setting. We summarized previous age data of the middle Permian to Middle Jurassic magmtaic rocks in the Erguna and Xing'an Massifs and identified two isolated phases of magmatic activity including the ca. 267-225 Ma and ca. 215-165 Ma periods, with a significant magmatic gap at ca. 225-215 Ma. These middle Permian to Middle Jurassic magmatic rocks are closely related to the southward subduction of the Mongol-Okhotsk ocean. A two-stage tectonic evolutionary model was proposed to account for these geological observations in the Erguna and Xing'an massifs, involving Permian to Middle Triassic continuous southward subduction of the Mongol-Okhotsk oceanic plate and Late Triassic to Jurassic slab-rollback and supra subduction extension.

  17. A new mid-Permian burnetiamorph therapsid from the Main Karoo Basin of South Africa and a phylogenetic review of Burnetiamorpha

    Directory of Open Access Journals (Sweden)

    Michael O. Day

    2016-12-01

    Full Text Available Discoveries of burnetiamorph therapsids in the last decade and a half have increased their known diversity but they remain a minor constituent of middle–late Permian tetrapod faunas. In the Main Karoo Basin of South Africa, from where the clade is traditionally best known, specimens have been reported from all of the Permian biozones except the Eodicynodon and Pristerognathus assemblage zones. Although the addition of new taxa has provided more evidence for burnetiamorph synapomorphies, phylogenetic hypotheses for the clade remain incongruent with their appearances in the stratigraphic column. Here we describe a new burnetiamorph specimen (BP/1/7098 from the Pristerognathus Assemblage Zone and review the phylogeny of the Burnetiamorpha through a comprehensive comparison of known material. Phylogenetic analysis suggests that BP/1/7098 is closely related to the Russian species Niuksenitia sukhonensis. Remarkably, the supposed mid-Permian burnetiids Bullacephalus and Pachydectes are not recovered as burnetiids and in most cases are not burnetiamorphs at all, instead representing an earlier-diverging clade of biarmosuchians that are characterised by their large size, dentigerous transverse process of the pterygoid and exclusion of the jugal from the lateral temporal fenestra. The evolution of pachyostosis therefore appears to have occurred independently in these genera. The resulting biarmosuchian tree is significantly more congruent with the stratigraphic appearance of its constituent taxa than in previous phylogenetic hypotheses and, consequently, does not necessarily constrain the diversification of the Burnetiamorpha to before the Capitanian.

  18. Stratigraphy and paleogeographic significance of a Late Pennsylvanian to Early Permian channeled slope sequence in the Darwin Basin, southern Darwin Hills, east-central California

    Science.gov (United States)

    Stevens, Calvin H.; Stone, Paul; Magginetti, Robert T.; Ritter, Scott M.

    2015-01-01

    The complex stratigraphy of late Paleozoic rocks in the southern Darwin Hills consists of regionally extensive Mississippian and Early to Middle Pennsylvanian rocks overlain by latest Pennsylvanian to Early Permian rocks, herein called the Darwin Hills sequence. Deposition of this latter sequence marked the beginning of the Darwin Basin. In Mississippian time, a carbonate platform prograded westward over slightly older slope deposits. In the Late Mississippian this platform was exposed to erosion and siliciclastic sediments were deposited. In Early to Middle Pennsylvanian time the area subsided, forming a west-facing ramp that was subjected to deformation and erosion in Middle or early Late Pennsylvanian time. Later this area was tilted westward and deep-water sediments were deposited on this slope. In latest Pennsylvanian to earliest Permian time, a major channel was cut through the older Pennsylvanian rocks and into the Upper Mississippian strata. This channel was gradually filled with increasingly finer grained, deep-water sediment as the area evolved into a basin floor by Early Permian (Sakmarian) time. Expansion of the Darwin Basin in Artinskian time led to a second phase of deposition represented by strata of the regionally extensive Darwin Canyon Formation. The geology in this small area thus documents tectonic events occurring during the early development of the Darwin Basin.

  19. Contrasting styles of aeolian, fluvial and marine interaction in the Cutler Group of the Paradox Basin, SE Utah, USA

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    Wakefield, Oliver; Mountney, Nigel

    2017-01-01

    The Permian-Pennsylvanian Cutler Group of the Paradox foreland basin of southeast Utah is characterised by a variety of styles of interaction between coeval aeolian, fluvial and marine environments that have resulted in the generation and preservation of a complex suite of stratal architectures. Detailed 3D architectural element analysis has enabled the nature of these interactions to be interpreted in order to constrain both the spatial and temporal scale over which competing ...

  20. Bauxite to eclogite: Evidence for late Permian supracontinental subduction at the Red River shear zone, northern Vietnam

    Science.gov (United States)

    Nakano, Nobuhiko; Osanai, Yasuhito; Nam, Nguyen Van; Tri, Tran Van

    2018-03-01

    age can be regarded as recording a prograde stage of metamorphism under conditions lower than 600 °C and 0.7 GPa. Our new data provide the following geological and tectonic constraints: 1) the eruption of basalt occurred before the Permian, possibly related to subduction of the Paleo-Tethys Plate beneath the Indochina craton near the paleo-equator in the Devonian-Carboniferous; 2) strong weathering transformed the basalt to bauxite before the late Permian; 3) the uppermost continental crust, including the bauxites, was subducted in the late Permian due to the collision of the Indochina and South China cratons, leading to eclogite-facies metamorphism; 4) the rocks were then exhumed; and 5) shearing-related thermal events took place until the Paleogene.

  1. Permian to recent volcanism in northern sumatra, indonesia: a preliminary study of its distribution, chemistry, and peculiarities

    Science.gov (United States)

    Rock, N. M. S.; Syah, H. H.; Davis, A. E.; Hutchison, D.; Styles, M. T.; Lena, Rahayu

    1982-06-01

    Sumatra has been a ‘volcanic arc’, above an NE-dipping subduction zone, since at least the Late Permian. The principal volcanic episodes in Sumatra N of the Equator have been in the Late Permian, Late Mesozoic, Palaeogene, Miocene and Quaternary. Late Permian volcanic rocks, of limited extent, are altered porphyritic basic lavas interstratified with limestones and phyllites. Late Mesozoic volcanic rocks, widely distributed along and W of the major transcurrent. Sumatra Fault System (SFS), which axially bisects Sumatra, include ophiolite-related spilites, andesites and basalts. Possible Palaeogene volcanic rocks include an altered basalt pile with associated dyke-swarm in the extreme NW, intruded by an Early Miocene (19 my) dioritic stock; and variable pyroxene rich basic lavas and agglomerates ranging from alkali basaltic to absarokitic in the extreme SW. Miocene volcanic rocks, widely distributed (especially W of the SFS), and cropping out extensively along the W coast, include calc-alkaline to high-K calc-alkaline basalts, andesites and dacites. Quaternary volcanoes (3 active, 14 dormant or extinct) are irregularly distributed both along and across the arc; thus they lie fore-arc of the SFS near the Equator but well back-arc farther north. The largest concentration of centres, around Lake Toba, includes the >2000 km3 Pleistocene rhyolitic Toba Tuffs. Quaternary volcanics are mainly calc-alkaline andesites, dacites and rhyolites with few basalts; they seem less variable, but on the whole more acid, than the Tertiary. The Quaternary volcanism is anomalous in relation to both southern Sumatra and adjacent Java/Bali: in southern Sumatra, volcanoes are regularly spaced along and successively less active away from the SFS, but neither rule holds in northern Sumatra. Depths to the subduction zone below major calc-alkaline volcanoes in Java/Bali are 160-210 km, but little over 100 km in northern Sumatra, which also lacks the regular K2O-depth correlations seen in

  2. Timing of the Permian-Triassic biotic crisis: implications from new zircon U/Pb age data (and their limitations)

    Science.gov (United States)

    Mundil, Roland; Metcalfe, Ian; Ludwig, Kenneth R.; Renne, Paul R.; Oberli, Felix; Nicoll, Robert S.

    2001-04-01

    The most profound biotic crisis in the Earth's history, causing the near extinction of both terrestrial and marine life, occurred at the end of the Permian period about 253 Myr ago and marks the Paleozoic-Mesozoic era boundary. The cause of this event is still a matter of vigorous debate, with both brief and catastrophic as well as gradual mechanisms having been proposed. Similar to a recent landmark study, this study uses the U-Pb method on zircons from the uppermost Permian/lowermost Triassic ash fall deposits at Meishan (Zhejiang Province, SE China) in order to examine time and rate constraints for these events. The results of both this study and previous work show that for these ash layers, the effects of Pb loss are combined with varying amounts and sources of inheritance, resulting in an age scatter which prohibits the extraction of a statistically robust age in many cases. Though the effects of Pb loss on the zircons analyzed in this study were reduced by leaching the grains in hydrofluoric acid (as opposed to commonly applied air abrasion) prior to analysis, the presence within a single ash layer of multiple generations of older xenocrysts (in many cases only slightly older than the depositional age) has made quantitative interpretation even more difficult. When these combined phenomena bias individual zircon ages by less than a percent, they are extremely difficult to deconvolute, and, if multi-grain analyses are used, can become impossible to recognize (because of the resulting age averaging). Monte Carlo simulations using actual measurements of individual zircon crystals show that age excursions due to Pb loss and xenocrystic contamination for the Meishan bentonites are easily homogenized to the point of undetectability when replicate analyses of multi-grain zircon samples are compared. Thus this study uses only high-precision analyses of single crystals, whether from our work or that of previous studies. Three main conclusions have emerged. First, our

  3. Salinity changes and anoxia resulting from enhanced run-off during the late Permian global warming and mass extinction event

    Directory of Open Access Journals (Sweden)

    E. E. van Soelen

    2018-04-01

    Full Text Available The late Permian biotic crisis had a major impact on marine and terrestrial environments. Rising CO2 levels following Siberian Trap volcanic activity were likely responsible for expanding marine anoxia and elevated water temperatures. This study focuses on one of the stratigraphically most expanded Permian–Triassic records known, from Jameson Land, East Greenland. High-resolution sampling allows for a detailed reconstruction of the changing environmental conditions during the extinction event and the development of anoxic water conditions. Since very little is known about how salinity was affected during the extinction event, we especially focus on the aquatic palynomorphs and infer changes in salinity from changes in the assemblage and morphology. The start of the extinction event, here defined by a peak in spore : pollen, indicating disturbance and vegetation destruction in the terrestrial environment, postdates a negative excursion in the total organic carbon, but predates the development of anoxia in the basin. Based on the newest estimations for sedimentation rates, the marine and terrestrial ecosystem collapse took between 1.6 and 8 kyr, a much shorter interval than previously estimated. The palynofacies and palynomorph records show that the environmental changes can be explained by enhanced run-off and increased primary productivity and water column stratification. A lowering in salinity is supported by changes in the acritarch morphology. The length of the processes of the acritarchs becomes shorter during the extinction event and we propose that these changes are evidence for a reduction in salinity in the shallow marine setting of the study site. This inference is supported by changes in acritarch distribution, which suggest a change in palaeoenvironment from open marine conditions before the start of the extinction event to more nearshore conditions during and after the crisis. In a period of sea-level rise, such a reduction

  4. Astronomical timescale calibration for the Permian-Triassic boundary transition interval from global correlation of cyclic marine sequences

    Science.gov (United States)

    Huang, C.; Hinnov, L. A.; Tong, J.; Chen, Z.

    2011-12-01

    The mass extinctions near the Permian-Triassic boundary (PTB) resulted in the greatest dying of life on Earth. The cause of this catastrophe remains enigmatic. High-resolution chronology is crucial to understanding the recorded pattern of biotic evolution and possible causes for the extinctions. Magnetic susceptibility (MS) data from Shangsi, South China shows evidence for astronomical forcing through the PTB interval, with strong 405-kyr cycling. This allows development of an astrochronology for the PTB interval based on the 405-kyr orbital eccentricity metronome that has been proposed for the Mesozoic timescale. Radioisotope dating combined with the 405-kyr tuned MS series from Shangsi shows that the 405-kyr-cycle predominates throughout the PTB interval. In the Permian segment, ~100-kyr cyclicity dominates, and the 100-kyr-scale MS maxima correlate with high-amplitude precession-scale MS variations. Minima in the ~1.5-Myr, 405-kyr and ~100-kyr cycles converge at 252.6 Ma, approximately 200 kyr before the onset of the main mass extinction near the PTB. In the Triassic aftermath, the recorded astronomical signal is different, with predominant 405-kyr cycles and loss of 100 kyr cyclicity, and appearance of ~33 kyr (obliquity scale) cyclicity; 100-kyr cyclicity strengthens again 2 Myr later. This pattern indicates a change in the response of the depositional environment (or magnetic susceptibility) to astronomical forcing before and after the mass extinction interval. The astrochronology interpolates the timescale between the radioisotopically determined absolute dates; this facilitates estimation of ages for specific events in the PTB crisis, including magnetic reversals, biozone boundaries, and the mass extinctions. An estimated ~700 kyr duration for the Mass Extinction Interval (MEI) at Shangsi based on the 405-kyr tuning is supported by eccentricity-tuned estimates of three other sections in China (Meishan, Huangzhishan, and Heping), and two Alpine sections

  5. Late Permian Palynology and depositional environment of Chintalapudi sub basin, Pranhita-Godavari basin, Andhra Pradesh, India

    Science.gov (United States)

    Jha, Neerja; Pauline Sabina, K.; Aggarwal, Neha; Mahesh, S.

    2014-01-01

    The present study deals with the palynological dating, correlation and depositional setting of the sediments from bore cores MGP-11 and MGP-4 from Gauridevipet area of Chintalapudi sub-basin of Godavari master basin, south India. On the basis of palynological studies, three palynoassemblages have been identified, one in bore core MGP-11 a Faunipollenites (=Protohaploxypinus) and Striasulcites assemblage and two in bore core MGP-4; one is characterized by the dominance of striate bisaccates and Densipollenites and the other by Striatopodocarpites and Cresentipollenites palynoassemblages. The other stratigraphically significant taxa include Guttulapollenites hannonicus, Lunatisporites noviaulensis, Lunatisporites pellucidus, Densoisporites contactus, Chordasporites australiensis, Goubinispora spp., Lundbladispora microconata, Lundbladispora raniganjensis and Klausipollenites schaubergeri. The recovered taxa suggest a Late Permian, Lopingian age for these rocks. This interpretation is based on the correlation of the assemblages with similar assemblages from previous Gondwana studies chiefly Densipollenites magnicorpus Zone of Damodar Basin, India and Late Permian palynoassemblages from Africa, Antarctica, Australia and South America. On the basis of palaeobotanical affinity of the identified microflora it has been inferred that the peat forming plant community was composed mainly of gymnosperm pollen attributable to glossopterids, that includes striate and non-striate bisaccates and paucity of cordaites which includes monosaccates. Spores are subordinate and are derived from lycopsids (Lundbladispora, Densoisporites), sphenopsids (Latosporites) and filicopsids (Horriditriletes, Lophotriletes, Verrucosisporites, Osmundacidites, Leiotriletes, Callumispora, Brevitriletes and Microbaculispora) occurring in variable proportions. The dominance of subarborescent/arborescent vegetation suggests a development in a forest swamp probably in a small distant marginal part of the

  6. Major factors controlling fracture development in the Middle Permian Lucaogou Formation tight oil reservoir, Junggar Basin, NW China

    Science.gov (United States)

    Zhang, Chen; Zhu, Deyu; Luo, Qun; Liu, Luofu; Liu, Dongdong; Yan, Lin; Zhang, Yunzhao

    2017-09-01

    Natural fractures in seven wells from the Middle Permian Lucaogou Formation in the Junggar Basin were evaluated in light of regional structural evolution, tight reservoir geochemistry (including TOC and mineral composition), carbon and oxygen isotopes of calcite-filled fractures, and acoustic emission (AE). Factors controlling the development of natural fractures were analyzed using qualitative and/or semi-quantitative techniques, with results showing that tectonic factors are the primary control on fracture development in the Middle Permian Lucaogou Formation of the Junggar Basin. Analyses of calcite, dolomite, and TOC show positive correlations with the number of fractures, while deltaic lithofacies appear to be the most favorable for fracture development. Mineral content was found to be a major control on tectonic fracture development, while TOC content and sedimentary facies mainly control bedding fractures. Carbon and oxygen isotopes vary greatly in calcite-filled fractures (δ13C ranges from 0.87‰ to 7.98‰, while δ18O ranges from -12.63‰ to -5.65‰), indicating that fracture development increases with intensified tectonic activity or enhanced diagenetic alteration. By analyzing the cross-cutting relationships of fractures in core, as well as four Kaiser Effect points in the acoustic emission curve, we observed four stages of tectonic fracture development. First-stage fractures are extensional, and were generated in the late Triassic, with calcite fracture fills formed between 36.51 °C and 56.89 °C. Second-stage fractures are shear fractures caused by extrusion stress from the southwest to the northeast, generated by the rapid uplift of the Tianshan in the Middle and Late Jurassic; calcite fracture fills formed between 62.91 °C and 69.88 °C. Third-stage fractures are NNW-trending shear fractures that resulted from north-south extrusion and thrusting in a foreland depression along the front of the Early Cretaceous Bogda Mountains. Calcite fracture

  7. Tumor-specific detection of an optically targeted antibody combined with a quencher-conjugated neutravidin "quencher-chaser": a dual "quench and chase" strategy to improve target to nontarget ratios for molecular imaging of cancer.

    Science.gov (United States)

    Ogawa, Mikako; Kosaka, Nobuyuki; Choyke, Peter L; Kobayashi, Hisataka

    2009-01-01

    In vivo molecular cancer imaging with monoclonal antibodies has great potential not only for cancer detection, but also for cancer characterization. However, the prolonged retention of intravenously injected antibody in the blood causes low target tumor-to-background ratio (TBR). Avidin has been used as a "chase" to clear the unbound, circulating biotinylated antibody and decrease the background signal. Here, we utilize a combined approach of a fluorescence resonance energy transfer (FRET) quenched antibody with an "avidin chase" to increase TBR. Trastuzumab, a humanized monoclonal antibody against human epidermal growth factor receptor type 2 (HER2), was biotinylated and conjugated with the near-infrared (NIR) fluorophore Alexa680 to synthesize Tra-Alexa680-biotin. Next, the FRET quencher, QSY-21, was conjugated to avidin, neutravidin (nAv), or streptavidin (sAv), thus creating Av-QSY21, nAv-QSY21, or sAv-QSY21 as "chasers". The fluorescence was quenched in vitro by binding Tra-Alexa680-biotin to Av-QSY21, nAv-QSY21, or sAv-QSY21. To evaluate if the injection of quencher-conjugated avidin derivatives can improve target TBR by using a dual "quench and chase" strategy, both target (3T3/HER2+) and nontarget (Balb3T3/ZsGreen) tumor-bearing mice were employed. The "FRET quench" effect induced by all the QSY21 avidin-based conjugates reduced but did not totally eliminate background signal from the blood pool. The addition of nAv-QSY21 administration increased target TBR mainly because of the "chase" effect where unbound conjugated antibody was preferentially cleared to the liver. The relatively slow clearance of unbound nAv-QSY21 leads to further reductions in background signal by leaking out of the vascular space and binding to unbound antibodies in the extravascular space of tumors, resulting in decreased nontarget tumor-to-background ratios but increased target TBR due to the "FRET quench" effect, because target-bound antibodies were internalized and could not bind

  8. DICKINSARTELLA FAUNA FROM THE SAIWAN FORMATION (OMAN: A BIVALVE FAUNA TESTIFYING TO THE LATE SAKMARIAN (EARLY PERMIAN CLIMATIC AMELIORATION ALONG THE NORTH-EASTERN GONDWANAN FRINGE.

    Directory of Open Access Journals (Sweden)

    CRISTIANO LARGHI

    2005-11-01

    Full Text Available The transitional faunas of the Permian Huqf succession of Oman make it one of the key-sections for the intercalibration of Early to Middle Permian biostratigraphical scales. The abundance of fossils improved the knowledge of some marine faunas which populated the North-Eastern Gondwanan fringe during times of climatic changes in the Permian. A Sterlitamakian (upper Sakmarian, Lower Permian bivalve fauna from the Saiwan Formation in the Huqf area, informally named "Dickinsartella Fauna", is described in the present paper. The specimens examined were collected from the "Pachycyrtella Bed" (Auctorum, the basal bed of the Formation in its type locality. The Dickinsartella Fauna can be identified for the presence of the new genus Dickinsartella, which dominates the bivalve thanatocoenosis with D. pistacina sp. n. (type species. The bivalve fauna from the Pachycyrtella Bed includes the new species Stutchburia sangallii and Promytilus  mazzolenii, and also Astartella obliqua Dickins, 1963, Nuculopsis cf. bangarraensis Dickins, 1963, ?Oriocrassatella sp., and indeterminable aviculopectinids. This fauna shows a low taxonomic diversity. Nevertheless, some species are represented by a high number of generally well-preserved specimens, i.e. some specimens of S. sangallii sp. n. and A. obliqua show part of the ligament.  The good preservation of the shells permitted the microstructural analysis of D. pistacina sp. n. and S. sangallii sp. n. The microstructure of S. sangallii sp. n. supports the close phylogenetical link between modiomorphids and crassatelloids recognized by some previous authors.The new genus Dickinsartella includes the more recent species belonging to the important Paleozoic Order Cyrtodontida Scarlato & Starobogatov, 1971. The discovery of Dickinsartella gen. n. and other taxa of the Pachycyrtella Bed, present also in the Sakmarian levels of the Carnarvon and Perth Basins in Western Australia,  indicates a wider distribution of the

  9. PLAY ANALYSIS AND DIGITAL PORTFOLIO OF MAJOR OIL RESERVOIRS IN THE PERMIAN BASIN: APPLICATION AND TRANSFER OF ADVANCED GEOLOGICAL AND ENGINEERING TECHNOLOGIES FOR INCREMENTAL PRODUCTION OPPORTUNITIES

    Energy Technology Data Exchange (ETDEWEB)

    Shirley P. Dutton; Eugene M. Kim; Ronald F. Broadhead; Caroline L. Breton; William D. Raatz; Stephen C. Ruppel; Charles Kerans

    2004-05-01

    The Permian Basin of west Texas and southeast New Mexico has produced >30 Bbbl (4.77 x 10{sup 9} m{sup 3}) of oil through 2000, most of it from 1,339 reservoirs having individual cumulative production >1 MMbbl (1.59 x 10{sup 5} m{sup 3}). These significant-sized reservoirs are the focus of this report. Thirty-two Permian Basin oil plays were defined, and each of the 1,339 significant-sized reservoirs was assigned to a play. The reservoirs were mapped and compiled in a Geographic Information System (GIS) by play. Associated reservoir information within linked data tables includes Railroad Commission of Texas reservoir number and district (Texas only), official field and reservoir name, year reservoir was discovered, depth to top of the reservoir, production in 2000, and cumulative production through 2000. Some tables also list subplays. Play boundaries were drawn for each play; the boundaries include areas where fields in that play occur but are <1 MMbbl (1.59 x 10{sup 5} m{sup 3}) of cumulative production. This report contains a summary description of each play, including key reservoir characteristics and successful reservoir-management practices that have been used in the play. The CD accompanying the report contains a pdf version of the report, the GIS project, pdf maps of all plays, and digital data files. Oil production from the reservoirs in the Permian Basin having cumulative production >1 MMbbl (1.59 x 10{sup 5} m{sup 3}) was 301.4 MMbbl (4.79 x 10{sup 7} m{sup 3}) in 2000. Cumulative Permian Basin production through 2000 from these significant-sized reservoirs was 28.9 Bbbl (4.59 x 10{sup 9} m{sup 3}). The top four plays in cumulative production are the Northwest Shelf San Andres Platform Carbonate play (3.97 Bbbl [6.31 x 10{sup 8} m{sup 3}]), the Leonard Restricted Platform Carbonate play (3.30 Bbbl 5.25 x 10{sup 8} m{sup 3}), the Pennsylvanian and Lower Permian Horseshoe Atoll Carbonate play (2.70 Bbbl [4.29 x 10{sup 8} m{sup 3}]), and the San Andres

  10. Permian U-Pb (CA-TIMS) zircon ages from Australia and China: Constraining the time scale of environmental and biotic change

    Science.gov (United States)

    Denyszyn, S. W.; Mundil, R.; Metcalfe, I.; He, B.

    2010-12-01

    In eastern Australia, the interconnected Bowen and Sydney Basins are filled with terrestrial sediments of late Paleozoic to early Mesozoic age. These sedimentary units record significant evolutionary events of eastern Gondwana during the time interval between two major mass extinctions (end Middle Permian and Permian-Triassic), and also provide lithological evidence for the Carboniferous-Permian Late Paleozoic Ice Age of southern Pangea, considered to be divisible into up to seven discrete glaciation events in Australia [e.g., 1]. These glaciations are currently assigned ages that indicate that the last of the glaciations predate the end Middle Permian mass extinction at ca. 260 Ma. However, the estimates for the time and durations are largely based on biostratigraphy and lithostratigraphy that, in the absence of robust and precise radioisotopic ages, are unacceptably fragile for providing an accurate high-resolution framework. Interbedded with the sediments are numerous tuff layers that contain zircon, many of which are associated with extensive coal measures in the Sydney and Bowen Basins. Published SHRIMP U-Pb zircon ages [2, 3] have been shown to be less precise and inaccurate when compared to ages applying the CA-TIMS method to the same horizons. Also within the late Middle Permian, the eruption of the Emeishan flood basalts in SW China has been proposed to have caused the end Middle Permian mass extinction [e.g., 4], though a causal link between these events demands a rigorous test that can only be provided by high-resolution geochronology. We present new U-Pb (CA-TIMS) zircon ages on tuff layers from the Sydney and Bowen Basins, with the purpose of generating a timescale for the Upper Permian of Australia to allow correlation with different parts of the world. Initial results, with permil precision, date a tuff layer within the uppermost Bandanna Fm. to ca. 252 Ma, a tuff within the Moranbah Coal Measures to ca. 256 Ma, and a tuff within the Ingelara Fm. to

  11. Geochemistry of radioactive elements in bituminous sands and sandstones of Permian bitumen deposits of Tatarstan (east of the Russian plate)

    Science.gov (United States)

    Mullakaev, A. I.; Khasanov, R. R.; Badrutdinov, O. R.; Kamaletdinov, I. R.

    2018-05-01

    The article investigates geochemical features of Permian (Cisuralian, Ufimian Stage and Biarmian, Kazanian Stage of the General Stratigraphic Scale of Russia) bituminous sands and sandstones located on the territory of the Volga-Ural oil and gas province (Republic of Tatarstan). Natural bitumens are extracted using thermal methods as deposits of high-viscosity oils. In the samples studied, the specific activity of natural radionuclides from the 238U (226Ra), 232Th, and 40K series was measured using gamma spectrometry. As a result of the precipitation of uranium and thorium and their subsequent decay, the accumulation of radium (226Ra and 228Ra) has been shown to occur in the bituminous substance. In the process of exploitation of bitumen-bearing rock deposits (as an oil fields) radium in the composition of a water-oil mixture can be extracted to the surface or deposited on sulfate barriers, while being concentrated on the walls of pipes and other equipment. This process requires increased attention to monitoring and inspection the environmental safety of the exploitation procedure.

  12. Late Permian marine ecosystem collapse began in deeper waters: evidence from brachiopod diversity and body size changes.

    Science.gov (United States)

    He, W-H; Shi, G R; Twitchett, R J; Zhang, Y; Zhang, K-X; Song, H-J; Yue, M-L; Wu, S-B; Wu, H-T; Yang, T-L; Xiao, Y-F

    2015-03-01

    Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming. © 2014 John Wiley & Sons Ltd.

  13. Rapid enhancement of chemical weathering recorded by extremely light seawater lithium isotopes at the Permian-Triassic boundary

    Science.gov (United States)

    Sun, He; Xiao, Yilin; Gao, Yongjun; Zhang, Guijie; Casey, John F.; Shen, Yanan

    2018-04-01

    Lithium (Li) isotope analyses of sedimentary rocks from the Meishan section in South China reveal extremely light seawater Li isotopic signatures at the Permian–Triassic boundary (PTB), which coincide with the most severe mass extinction in the history of animal life. Using a dynamic seawater lithium box model, we show that the light seawater Li isotopic signatures can be best explained by a significant influx of riverine [Li] with light δ7Li to the ocean realm. The seawater Li isotope excursion started ≥300 Ky before and persisted up to the main extinction event, which is consistent with the eruption time of the Siberian Traps. The eruption of the Siberian Traps exposed an enormous amount of fresh basalt and triggered CO2 release, rapid global warming, and acid rains, which in turn led to a rapid enhancement of continental weathering. The enhanced continental weathering delivered excessive nutrients to the oceans that could lead to marine eutrophication, anoxia, acidification, and ecological perturbation, ultimately resulting in the end-Permian mass extinction.

  14. Boreal earliest Triassic biotas elucidate globally depauperate hard substrate communities after the end-Permian mass extinction.

    Science.gov (United States)

    Zatoń, Michał; Niedźwiedzki, Grzegorz; Blom, Henning; Kear, Benjamin P

    2016-11-08

    The end-Permian mass extinction constituted the most devastating biotic crisis of the Phanerozoic. Its aftermath was characterized by harsh marine conditions incorporating volcanically induced oceanic warming, widespread anoxia and acidification. Bio-productivity accordingly experienced marked fluctuations. In particular, low palaeolatitude hard substrate communities from shallow seas fringing Western Pangaea and the Tethyan Realm were extremely impoverished, being dominated by monogeneric colonies of filter-feeding microconchid tubeworms. Here we present the first equivalent field data for Boreal hard substrate assemblages from the earliest Triassic (Induan) of East Greenland. This region bordered a discrete bio-realm situated at mid-high palaeolatitude (>30°N). Nevertheless, hard substrate biotas were compositionally identical to those from elsewhere, with microconchids encrusting Claraia bivalves and algal buildups on the sea floor. Biostratigraphical correlation further shows that Boreal microconchids underwent progressive tube modification and unique taxic diversification concordant with changing habitats over time. We interpret this as a post-extinction recovery and adaptive radiation sequence that mirrored coeval subequatorial faunas, and thus confirms hard substrate ecosystem depletion as a hallmark of the earliest Triassic interval globally.

  15. Response of carbon isotopic compositions of Early-Middle Permian coals in North China to palaeo-climate change

    Science.gov (United States)

    Ding, Dianshi; Liu, Guijian; Sun, Xiaohui; Sun, Ruoyu

    2018-01-01

    To investigate the magnitude to which the carbon isotopic ratio (δ13C) varies in coals in response to their contemporary terrestrial environment, the Early-Middle Permian Huainan coals (including coals from the Shanxi Formation, Lower Shihezi Formation and Upper Shihezi Formation) in North China were systematically sampled. A 2.5‰ variation range of δ13C values (-25.15‰ to -22.65‰) was observed in Huainan coals, with an average value of -24.06‰. As coal diagenesis exerts little influence on carbon isotope fractionation, δ13C values in coals were mainly imparted by those of coal-forming flora assemblages which were linked to the contemporary climate. The δ13C values in coals from the Shanxi and Lower Shihezi Formations are variable, reflecting unstable climatic oscillations. Heavy carbon isotope is enriched in coals of the Capitanian Upper Shihezi Formation, implying a shift to high positive δ13C values of coeval atmospheric CO2. Notably, our study provides evidence of the Kamura event in the terrestrial environment for the first time.

  16. Contrasting origin of two A-type rhyolite series from the Early Permian Nomgon bimodal volcanic association (Southern Mongolia)

    Science.gov (United States)

    Kozlovsky, A. M.; Yarmolyuk, V. V.; Savatenkov, V. M.; Kudryashova, E. A.

    2017-08-01

    A-type rhyolites of contrasting compositions and eruption characters were revealed among two volcanic series of the Early Permian bimodal association in the Nomgon graben. Rhyolites of the lower volcanic series formed extrusions, lava domes, and tuff horizons. They had low FeOt, Zr, Hf, Nb, Ta, Y, and REE concentrations and also a moderately depleted Nd isotope composition (ɛNd( T) = 6.7-7.1). Their formation was related to anatexis of the juvenile continental crust, triggered by the thermal effect of mafic magmas. Rhyolites of the upper volcanic series formed extensive lava flows and dikes. Their composition was characterized by high FeOt, Zr, Hf, Nb, Ta, Y, and REE concentrations, and also depleted Nd isotope characteristics (ɛNd( T) = 7.7-9.0). These rhyolite melts formed under long-term crystallizational differentiation of basaltoids in the intracrustal magmatic chambers, with limited participation of crustal contamination. The source of magmas for the upper volcanic series was the sublithospheric mantle.

  17. Trajectories of Late Permian – Jurassic radiolarian extinction rates: no evidence for an end-Triassic mass extinction

    Directory of Open Access Journals (Sweden)

    W. Kiessling

    2011-02-01

    Full Text Available The hypothesis that ocean acidification was a proximate trigger of the marine end-Triassic mass extinction rests on the assumption that taxa that strongly invest in the secretion of calcium-carbonate skeletons were significantly more affected by the crisis than other taxa. An argument against this hypothesis is the great extinction toll of radiolarians that has been reported from work on local sections. Radiolarians have siliceous tests and thus should be less affected by ocean acidification. We compiled taxonomically vetted occurrences of late Permian and Mesozoic radiolarians and analyzed extinction dynamics of radiolarian genera. Although extinction rates were high at the end of the Triassic, there is no evidence for a mass extinction in radiolarians but rather significantly higher background extinction in the Triassic than in the Jurassic. Although the causes for this decline in background extinction levels remain unclear, the lack of a major evolutionary response to the end-Triassic event, gives support for the hypothesis that ocean acidification was involved in the dramatic extinctions of many calcifying taxa. doi:10.1002/mmng.201000017

  18. Impacts of a massive release of methane and hydrogen sulfide on oxygen and ozone during the late Permian mass extinction

    Science.gov (United States)

    Kaiho, Kunio; Koga, Seizi

    2013-08-01

    The largest mass extinction of animals and plants in both the ocean and on land occurred in the late Permian (252 Ma), largely coinciding with the largest flood basalt volcanism event in Siberia and an oceanic anoxic/euxinic event. We investigated the impacts of a massive release of methane (CH4) from the Siberian igneous province and the ocean and/or hydrogen sulfide (H2S) from the euxinic ocean on oxygen and ozone using photochemical model calculations. Our calculations indicated that an approximate of 14% decrease in atmospheric O2 levels would have occurred in the case of a large combined CH4 and H2S flux to the atmosphere, whereas an approximate of 8 to 10% decrease would have occurred from the CH4 flux and oxidation of all H2S in the ocean. The slight decrease in atmospheric O2 levels may have contributed to the extinction event. We demonstrate for the first time that a massive release of CH4 from the Siberian igneous province and a coincident massive release of CH4 and H2S did not cause ozone collapse. A collapse of stratospheric ozone leading to an increase in UV is not supported by the maximum model input levels for CH4 and H2S. These conclusions on O2 and O3 are correspondent to every H2S release percentages from the ocean to the atmosphere.

  19. An upwelling model for the Phosphoria sea: A Permian, ocean-margin sea in the northwest United States

    Science.gov (United States)

    Piper, D.Z.; Link, P.K.

    2002-01-01

    The Permian Phosphoria Formation, a petroleum source rock and world-class phosphate deposit, was deposited in an epicratonic successor basin on the western margin of North America. We calculate the seawater circulation in the basin during deposition of the lower ore zone in the Meade Peak Member from the accumulation rates of carbonate fluorapatite and trace elements. The model gives the exchange rate of water between the Phosphoria sea and the open ocean to the west in terms of an upwelling rate (84 m yr-1) and residence time (4.2 yr) of seawater in the basin. These hydrographic properties supported a mean rate of primary productivity of 0.87 g m-2 d-1 of carbon in the uppermost few tens of meters of the water column (the photic zone) and denitrifying redox conditions in the bottom water (below approximately 150 m depth). High rain rates, onto the sea floor, of the organic matter that hosted the phosphate and several trace elements contributed to the accumulation of phosphorite, chert, and black shales and mudstones. Evaporation in the Goose Egg basin to the east of the Phosphoria basin ensured the import of surface seawater from the Phosphoria sea. Budgets of water, salt, phosphate, and oxygen, plus the minor accumulation of the biomarker gammacerane, show that exchange of water between the two basins was limited, possibly by the shallow carbonate platform that separated the two basins.

  20. Native copper in Permian Mudstones from South Devon: A natural analogue of copper canisters for high-level radioactive waste

    International Nuclear Information System (INIS)

    Milodowski, A.E.; Styles, M.T.; Werme, L.; Oversby, V.M.

    2001-01-01

    Native copper (>99.9% Cu) sheets associated with complex uraniferous and vanadiferous concretions in Upper Permian Mudstones from south Devon (United Kingdom) have been studied as a 'natural analogue' for copper canisters designed to be used in the isolation of spent fuel and high-level radioactive wastes (HLW) for deep geological disposal. Detailed analysis demonstrates that the copper formed before the mudstones were compacted. The copper displays complex corrosion and alteration. The earliest alteration was to copper oxides, followed sequentially by the formation of copper arsenides, nickel arsenide and copper sulphide, and finally nickel arsenide accompanied by nickel-copper arsenide, copper arsenide and uranium silicates. Petrographic observations demonstrate that these alteration products also formed prior to compaction. Consideration of the published history for the region indicates that maximum compaction of the rocks will have occurred by at least the Lower Jurassic (i.e. over 176 Ma ago). Since that time the copper sheets have remained isolated by the compacted mudstones and were unaffected by further corrosion until uplift and exposure to present-day surface weathering

  1. Carboniferous-Permian sedimentology and stratigraphy of the Nordfjorden High and Loppa Spur, Arctic Norway

    DEFF Research Database (Denmark)

    Ahlborn, Morten

    Abstract (shortened) Facies analysis of Late Paleozoic warm-water carbonates, were conducted in order to investigate the depositional evolution, cyclicity, internal architecture and sequence stratigraphy of the upper Gipsdalen Group carbonate platform on the Nordfjorden High in central Spitsberge...

  2. An isotope approach based on C-13 pulse-chase labelling vs. the root trenching method to separate heterotrophic and autotrophic respiration in cultivated peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Biasi, C.; Pitkamaki, A. S.; Tavi, N. M.; Koponen, H. T.; Martikainen, P. J. [Univ.of Eastern Finland, Kuopio (Finland). Dept. of Environmental Science], e-mail: christina.biasi@uef.fi

    2012-11-01

    We tested an isotope method based on C-13 pulse-chase labelling for determining the fractional contribution of soil microbial respiration to overall soil respiration in an organic soil (cutaway peatland, eastern Finland), cultivated with the bioenergy crop, reed canary grass. The plants were exposed to CO{sub 2}-13 for five hours and the label was thereafter determined in CO{sub 2} derived from the soil-root system. A two-pool isotope mixing model was used to separate sources of respiration. The isotopic approach showed that a minimum of 50% of the total CO{sub 2} originated from soil-microbial respiration. Even though the method uses undisturbed soil-plant systems, it has limitations concerning the experimental determination of the true isotopic signal of all components contributing to autotrophic respiration. A trenching experiment which was comparatively conducted resulted in a 71% fractional contribution of soil-microbial respiration. This value was likely overestimated. Further studies are needed to evaluate critically the output from these two partitioning approaches. (orig.)

  3. Circum-Pacific accretion of oceanic terranes to continental blocks: accretion of the Early Permian Dun Mountain ophiolite to the E Gondwana continental margin, South Island, New Zealand

    Science.gov (United States)

    Robertson, Alastair

    2016-04-01

    Accretionary orogens, in part, grow as a result of the accretion of oceanic terranes to pre-existing continental blocks, as in the circum-Pacific and central Asian regions. However, the accretionary processes involved remain poorly understood. Here, we consider settings in which oceanic crust formed in a supra-subduction zone setting and later accreted to continental terranes (some, themselves of accretionary origin). Good examples include some Late Cretaceous ophiolites in SE Turkey, the Jurassic Coast Range ophiolite, W USA and the Early Permian Dun Mountain ophiolite of South Island, New Zealand. In the last two cases, the ophiolites are depositionally overlain by coarse clastic sedimentary rocks (e.g. Permian Upukerora Formation of South Island, NZ) that then pass upwards into very thick continental margin fore-arc basin sequences (Great Valley sequence, California; Matai sequence, South Island, NZ). Field observations, together with petrographical and geochemical studies in South Island, NZ, summarised here, provide evidence of terrane accretion processes. In a proposed tectonic model, the Early Permian Dun Mountain ophiolite was created by supra-subduction zone spreading above a W-dipping subduction zone (comparable to the present-day Izu-Bonin arc and fore arc, W Pacific). The SSZ oceanic crust in the New Zealand example is inferred to have included an intra-oceanic magmatic arc, which is no longer exposed (other than within a melange unit in Southland), but which is documented by petrographic and geochemical evidence. An additional subduction zone is likely to have dipped westwards beneath the E Gondwana margin during the Permian. As a result, relatively buoyant Early Permian supra-subduction zone oceanic crust was able to dock with the E Gondwana continental margin, terminating intra-oceanic subduction (although the exact timing is debatable). The amalgamation ('soft collision') was accompanied by crustal extension of the newly accreted oceanic slab, and

  4. Early Permian transgressive-regressive cycles: Sequence stratigraphic reappraisal of the coal-bearing Barakar Formation, Raniganj Basin, India

    Science.gov (United States)

    Bhattacharya, Biplab; Bhattacharjee, Joyeeta; Bandyopadhyay, Sandip; Banerjee, Sudipto; Adhikari, Kalyan

    2018-03-01

    The present research is an attempt to assess the Barakar Formation of the Raniganj Gondwana Basin, India, in the frame of fluvio-marine (estuarine) depositional systems using sequence stratigraphic elements. Analysis of predominant facies associations signify deposition in three sub-environments: (i) a river-dominated bay-head delta zone in the inner estuary, with transition from braided fluvial channels (FA-B1) to tide-affected meandering fluvial channels and flood plains (FA-B2) in the basal part of the succession; (ii) a mixed energy central basin zone, which consists of transitional fluvio-tidal channels (FA-B2), tidal flats, associated with tidal channels and bars (FA-B3) in the middle-upper part of the succession; and (iii) a wave-dominated outer estuary (coastal) zone (FA-B4 with FA-B3) in the upper part of the succession. Stacked progradational (P1, P2)-retrogradational (R1, R2) successions attest to one major base level fluctuation, leading to distinct transgressive-regressive (T-R) cycles with development of initial falling stage systems tract (FSST), followed by lowstand systems tract (LST) and successive transgressive systems tracts (TST-1 and TST-2). Shift in the depositional regime from regressive to transgressive estuarine system in the early Permian Barakar Formation is attributed to change in accommodation space caused by mutual interactions of (i) base level fluctuations in response to climatic amelioration and (ii) basinal tectonisms (exhumation/sagging) related to post-glacial isostatic adjustments in the riftogenic Gondwana basins.

  5. The depositional environment and petrology of the White Rim Sandstone Member of the Permian Cutler Formation, Canyonlands National Park, Utah

    Science.gov (United States)

    Steele-Mallory, B. A.

    1982-01-01

    The White Rim Sandstone Member of the Cutler Formation of Permian age in Canyonlands National Park, Utah, was deposited in coastal eolian and associated interdune environments. This conclusion is based on stratigraphic relationships primary sedimentary structures, and petrologic features. The White Rim consists of two major genetic units. The first represents a coastal dune field and the second represents related interdune ponds. Distinctive sedimentary structures of the coastal dune unit include large- to medium-scale, unidirectional, tabular-planar cross-bedding; high-index ripples oriented parallel to dip direction of the foresets; coarse-grained lag layers; avalanche or slump marks; and raindrop impressions. Cross-bedding measurements suggest the dunes were deposited as transverse ridges by a dominantly northwest to southeast wind. Distinctive sedimentary structures of the interdune pond unit include wavy, horizontally laminated bedding, adhesion ripples, and desiccation polygons. These features may have been produced by alternate wetting and drying of sediment during water-table fluctuations. Evidence of bioturbation is also present in this unit. Petrologic characteristics of the White Rim helped to define the depositional environment as coastal. A crinoid fragment was identified at one location; both units are enriched in heavy minerals, and small amounts of well rounded, reworked glauconite were found in the White Rim throughout the study area. Earlier work indicates that the White Rim sandstone is late Wolfcampian to early Leonardian in age. During this time, the Canyonlands area was located in a depositional area alternately dominated by marine and nonmarine environments. Results of this study suggest the White Rim represents a coastal dune field that was deposited by predominantly on-shore winds during a period of marine transgression.

  6. A new U-Pb zircon age and a volcanogenic model for the early Permian Chemnitz Fossil Forest

    Science.gov (United States)

    Luthardt, Ludwig; Hofmann, Mandy; Linnemann, Ulf; Gerdes, Axel; Marko, Linda; Rößler, Ronny

    2018-04-01

    The Chemnitz Fossil Forest depicts one of the most completely preserved forest ecosystems in late Paleozoic Northern Hemisphere of tropical Pangaea. Fossil biota was preserved as a T0 taphocoenosis resulting from the instantaneous entombment by volcanic ashes of the Zeisigwald Tuff. The eruption depicts one of the late magmatic events of post-variscan rhyolitic volcanism in Central Europe. This study represents a multi-method evaluation of the pyroclastic ejecta encompassing sedimentological and (isotope) geochemical approaches to shed light on magmatic and volcanic processes, and their role in preserving the fossil assemblage. The Zeisigwald Tuff pyroclastics (ZTP) reveal a radiometric age of 291 ± 2 Ma, pointing to a late Sakmarian/early Artinskian (early Permian) stratigraphic position for the Chemnitz Fossil Forest. The initial eruption was of phreatomagmatic style producing deposits of cool, wet ashes, which deposited from pyroclastic fall out and density currents. Culmination of the eruption is reflected by massive hot and dry ignimbrites. Whole-rock geochemistry and zircon grain analysis show that pyroclastic deposits originated from a felsic, highly specialised magma, which underwent advanced fractionation, and is probably related to post-Carboniferous magmatism in the Western Erzgebirge. The ascending magma recycled old cadomic crust of the Saxo-thuringian zone, likely induced by a mantle-derived heat flow during a phase of post-variscan crustal delamination. Geochemical trends within the succession of the basal pyroclastic horizons reflect inverse zonation of the magma chamber and provide evidence for the continuous eruption and thus a simultaneous burial of the diverse ecosystem.

  7. High influx of carbon in walls of agglutinated foraminifers during the Permian-Triassic transition in global oceans

    Science.gov (United States)

    Nestell, Galina P.; Nestell, Merlynd K.; Ellwood, Brooks B.; Wardlaw, Bruce R.; Basu, Asish R.; Ghosh, Nilotpal; Phuong Lan, Luu Thi; Rowe, Harry D.; Hunt, Andrew G.; Tomkin, Jonathan H.; Ratcliffe, Kenneth T.

    2015-01-01

    The Permian–Triassic mass extinction is postulated to be related to the rapid volcanism that produced the Siberian flood basalt (Traps). Unrelated volcanic eruptions producing several episodes of ash falls synchronous with the Siberian Traps are found in South China and Australia. Such regional eruptions could have caused wildfires, burning of coal deposits, and the dispersion of coal fly ash. These eruptions introduced a major influx of carbon into the atmosphere and oceans that can be recognized in the wallstructure of foraminiferal tests present in survival populations in the boundary interval strata. Analysis of free specimens of foraminifers recovered from residues of conodont samples taken at aPermian–Triassic boundary section at Lung Cam in northern Vietnam has revealed the presence of a significant amount of elemental carbon, along with oxygen and silica, in their test wall structure, but an absence of calcium carbonate. These foraminifers, identified as Rectocornuspira kalhori, Cornuspira mahajeri, and Earlandia spp. and whose tests previously were considered to be calcareous, are confirmed to be agglutinated, and are now referred to as Ammodiscus kalhori and Hyperammina deformis. Measurement of the 207Pb/204Pb ratios in pyrite clusters attached to the foraminiferal tests confirmed that these tests inherited the Pb in their outer layer from carbon-contaminated seawater. We conclude that the source of the carbon could have been either global coal fly ash or forest fire-dispersed carbon, or a combination of both, that was dispersed into the Palaeo-Tethys Ocean immediately after the end-Permian extinction event.

  8. Petrophysical Properties of the Yeso, Abo and Cisco Formations in the Permian Basin in New Mexico, U.S.A

    Science.gov (United States)

    Mann, Griffin

    The area that comprises the Northwest Shelf in Lea Co., New Mexico has been heavily drilled over the past half century. The main target being shallow reservoirs within the Permian section (San Andres and Grayburg Formations). With a focus shifting towards deeper horizons, there is a need for more petrophysical data pertaining to these formations, which is the focus of this study through a variety of techniques. This study involves the use of contact angle measurements, fluid imbibition tests, Mercury Injection Capillary Pressure (MICP) and log analysis to evaluate the nano-petrophysical properties of the Yeso, Abo and Cisco Formation within the Northwest Shelf area of southeast New Mexico. From contact angle measurements, all of the samples studied were found to be oil-wetting as n-decane spreads on to the rock surface much quicker than the other fluids (deionized water and API brine) tested. Imbibition tests resulted in a well-connected pore network being observed for all of the samples with the highest values of imbibition slopes being recorded for the Abo samples. MICP provided a variety of pore structure data which include porosity, pore-throat size distributions, permeability and tortuosity. The Abo samples saw the highest porosity percentages, which were above 15%, with all the other samples ranging from 4 - 7%. The majority of the pore-throat sizes for most of the samples fell within the 1 - 10 mum range. The only exceptions to this being the Paddock Member within the Yeso Formation, which saw a higher percentage of larger pores (10 - 1000mum) and one of the Cisco Formation samples, which had the majority of its pore sizes fall in the 0.1 - 1 mum range. The log analysis created log calculations and curves for cross-plot porosity and water saturation that were then used to derive a value for permeability. The porosity and permeability values were comparable with those measured from our MICP and literature values.

  9. Morphology and histology of dorsal spines of the xenacanthid shark Orthacanthus platypternus from the Lower Permian of Texas, USA: palaeobiological and palaeoenvironmental implications

    Directory of Open Access Journals (Sweden)

    Kimberly G. Beck

    2016-02-01

    Full Text Available Detailed studies on Carboniferous species of the xenacanth Orthacanthus have shown that the xenacanth dorsal fin spine can be used for skeletochronological analyses and provides valuable information about development, growth and environmental life conditions of those extinct sharks. We report here for the first time the histology and skeletochronology of Permian specimens, dorsal spines of Orthacanthus platypternus from the Craddock Bone Bed (lower Clear Fork Formation; Early Permian, Leonardian age of northern Baylor County (north-central Texas, USA. Twelve dorsal spines of O. platypternus preserve a highly vascularized wall mainly composed of centrifugally growing dentine in a succession of dentine layers, probably deposited with an annual periodicity. As expected, spines of individuals with 1–2 dentine layers, presumably juveniles, present the smallest sizes. However, spines of individuals showing at least 3–4 dentine layers and interpreted to be subadults/young adults, are distributed in two spine-size clusters corresponding to females (probably the largest spines and males, in agreement with the hypothesis of sexual size dimorphism proposed in a previous biometric analysis. Our comparative study of O. platypternus and the Stephanian species O. meridionalis further suggests that spine denticulation can be useful for distinguishing between species of Orthacanthus and sexually dimorphic forms (juvenile to adults in each species. Total body length estimations of O. platypternus from the Craddock Bone Bed point to relatively large juveniles and small subadults/young adults (less than 2 m in total length, living as opportunistic predators in the pond-channel coastal plain environments represented by the bone bed deposits. The com-parative analyses of the ontogenetic stages of the recorded specimens of O. platypternus and their distribution along different facies and localities indicate that this species was euryhaline, diadromous with a

  10. High-Resolution Zircon U-Pb CA-TIMS Dating of the Carboniferous—Permian Successions, Paraná Basin, Brazil

    Science.gov (United States)

    Griffis, N. P.; Mundil, R.; Montanez, I. P.; Isbell, J.; Fedorchuk, N.; Lopes, R.; Vesely, F.; Iannuzzi, R.

    2015-12-01

    The late Paleozoic Ice Age (LPIA) is Earth's only record of a CO2-forced climatic transition from an icehouse to greenhouse state in a vegetated world. Despite a refined framework of Gondwanan ice distribution, questions remain about the timing, volume, and synchronicity of high-latitude continental ice and the subsequent deglaciation. These questions ultimately preclude our understanding of linkages between ice volume, sea level, and high- and low-latitude climate. Poor constraints on the timing and synchronicity of glacial and interglacial transitions reflect a lack of high-resolution radioisotopic dates from high-latitude, ice-proximal Carboniferous-Permian successions. The Rio Bonito Fm in Rio Grande do Sul State of southern Brazil hosts the oldest non-glaciogenic Carboniferous- Permian deposits of the Paraná Basin, thus recording the icehouse-to-greenhouse transition. Despite a widespread effort over the last two decades to constrain these deposits in time by means of U-Pb zircon geochronology, published data sets of the Candiota and Faxinal coals of the Rio Bonito Fm host discrepancies that may reflect post- eruptive open system behavior of zircon and analytical artifacts. These discrepancies have hindered the correlation of the Candiota and Faxinal sediments within the larger Gondwanan framework. Here we present the first U-Pb ages on closed system single zircons using CA-TIMS techniques on Permo-Carboniferous ash deposits of the Paraná Basin. Preliminary results indicate two major and distinct coal-forming periods that are separated by ca 10 Ma. Our results and conclusions are not in agreement with multi- crystal U-Pb TIMS and SIMS ages that suggest coeval deposition of the Candiota and Faxinal coals. CA-TIMS analyses applied to zircons from additional ash deposits are aimed at constructing a robust chronostratigraphic framework for the Carboniferous- Permian succession of the Paraná Basin, which will facilitate a better understanding of the timing and

  11. Inferred Early Permian Arc Rifting in Bogda Mountain, Southernmost of the Central Asia Orogenic Belt: Evidence from a Peperite Bearing Volcano-Sedimentary Succession

    Science.gov (United States)

    Memtimin, M.; Guo, Z.

    2017-12-01

    Late Paleozoic tectonic history, especially Carboniferous-Permian periods, of the Central Asia Orogenic Belt (CAOB) is considered to be the turning point for the termination of terrane amalgamation and closure of the Paleoasian Ocean. However, the debate about the paleoenvironment and tectonic setting of the region during the period is still not resolved. In this study, we report a set of volcano-sedimentary sequence in the Bogda Mountain of the southernmost of CAOB, which is associated with contemporaneous subaqueous emplacement of and interaction between mafic lava and carbonate sediments. The succession contains four distinct facies including closely packed pillow basalts, pillow basalts with interstitial materials, hyaloclastites and peperites. We discuss their formation and emplacement mechanism, interaction between hot magma-water/unconsolidated sediments and thermal metamorphism during the interaction. Textural features of the sequence, especially hyaloclastites and peperites, provide clear evidence for in situ autofragmentation of lava flows, synvolcanic sedimentation of carbonates, fuel coolant interaction when hot magma bulldozed into wet unconsolidated sediments, and represent autochthonous origin of the succession. Lateral transition of the lithofacies indicate a progressively deepening subaqueous environment, resembling a stepwise evolution from early stage of volcanic intrusion with lower lava flux in shallower water level to increasingly subsiding basin with more lava flux in greater depth. Previous studies determined that the mafic magma was intruded around the Carboniferous-Permian boundary ( 300Ma), and geochemical studies showed the magma was originated from dry depleted mantle with little crustal contamination. Nevertheless, the succession was thought to be fault related allochthones formation which was transferred in as part of a Carboniferous intraplate arc. Combining our findings with the previous study results, we propose a new model to

  12. Carboniferous and Permian evolutionary records for the Paleo-Tethys Ocean constrained by newly discovered Xiangtaohu ophiolites from central Qiangtang, central Tibet

    Science.gov (United States)

    Zhang, Xiu-Zheng; Dong, Yong-Sheng; Wang, Qiang; Dan, Wei; Zhang, Chunfu; Deng, Ming-Rong; Xu, Wang; Xia, Xiao-Ping; Zeng, Ji-Peng; Liang, He

    2016-07-01

    Reconstructing the evolutionary history of the Paleo-Tethys Ocean remains at the center of debates over the linkage between Gondwana dispersion and Asian accretion. Identifying the remnants of oceanic lithosphere (ophiolites) has very important implications for identifying suture zones, unveiling the evolutionary history of fossil oceans, and reconstructing the amalgamation history between different blocks. Here we report newly documented ophiolite suites from the Longmu Co-Shuanghu Suture zone (LSSZ) in the Xiangtaohu area, central Qiangtang block, Tibet. Detailed geological investigations and zircon U-Pb dating reveal that the Xiangtaohu ophiolites are composed of a suite of Permian (281-275 Ma) ophiolites with a nearly complete Penrose sequence and a suite of Early Carboniferous (circa 350 Ma) ophiolite remnants containing only part of the lower oceanic crust. Geochemical and Sr-Nd-O isotopic data show that the Permian and Carboniferous ophiolites in this study were derived from an N-mid-ocean ridge basalts-like mantle source with varied suprasubduction-zone (SSZ) signatures and were characterized by crystallization sequences from wet magmas, suggesting typical SSZ-affinity ophiolites. Permian and Carboniferous SSZ ophiolites in the central Qiangtang provide robust evidence for the existence and evolution of an ancient ocean basin. Combining with previous studies on high-pressure metamorphic rocks and pelagic radiolarian cherts, and with tectonostratigraphic and paleontological data, we support the LSSZ as representing the main suture of the Paleo-Tethys Ocean which probably existed and evolved from Devonian to Triassic. The opening and demise of the Paleo-Tethys Ocean dominated the formation of the major framework for the East and/or Southeast Asia.

  13. Rare-earths in size fractions and sedimentary rocks of Pennsylvanian-Permian age from the mid-continent of the U.S.A

    International Nuclear Information System (INIS)

    Cullers, R.; Chaudhuri, S.; Kilbane, N.; Koch, R.

    1979-01-01

    The REE (rare-earth) contents of sixty-three <2μ fractions of Pennsylvanian and Permian platform sediment from the mid-continent of the U.S.A. vary considerably (ΣREE = 46 to 439 ppm: La/Lu = 5.2 to 15.7; correlation coefficient of REE with La Lu = 0.89), but the Eu/Sm ratios are nearly constant even in reducing environments that concentrate U (0.16 to 0.22). There is no correlation of REE content to clay mineralogy. Lower Permian <2μ fractions from continental to nearshore marine sediment in Oklahoma have higher REE content (244 to 261 ppm) than marine facies in Kansas (46 to 140 ppm) but <2μ Upper Permian fractions in an evaporite basin have constant but high REE content (288 to 281 ppm; one = 153 ppm). All Pennsylvanian <2μ fractions from Oklahoma have high REE content (209 to 439 ppm), and fractions from Kansas cyclothems have variable REE content (86 to 438 ppm). REE content in the <2μ fractions is inherited from the provenance, but is modified by ion exchange during weathering, transportation or deposition. Exchangable REE tend to be concentrated in clay minerals in basic environments, but removed in acid environments. Sand and gravel-size fractions consist mostly of quartz or chert so their REE content is low (7.9 to 40.6 ppm) although heavy minerals may contribute a large fraction of the REE content. Unexpectedly silt-size fractions have REE contents (74 to 355 ppm) that are usually lower but similar to their <2μ fractions, and the REE contents do not correlate to clay mineral/quartz ratios. (author)

  14. New paleomagnetic results from the Permian and Mesozoic rocks in central and northeast Thailand: their implications for the construction of the Indochina block in Pangea

    Science.gov (United States)

    Zhang, D.; Yan, Y.; Huang, B.; Zhao, J.

    2015-12-01

    Paleomagnetic studies of the Indochina block, aiming to reconstruct the paleogeography, have been undertaken for several decades. Since the Indochina block is lack of reliable paleomagnetic data to constraint its paleo-positions during the Middle Permian to Upper Triassic, the paleogeography reconstruction is still in debate between different models reported. Here we present new paleomagnetic data of Middle Permian to Upper Triassic sediment rocks from the Indochina block in Thailand, and recalculate paleomagnetic data reported by different authors. We collected the Permian samples in 20 sites distributed in the central Thailand, and Triassic samples from the Huai Hin Lat and Nam Phong formations in 13 sites in the northern Thailand.The magnetic directions of the 11 sites of Permian limestones are not significantly clustered after tilt correction which implying a remagnetized result. Remarkably, in geographic coordinate, the 11 sites were distributed along a circle showing a similar inclination which is 22.9° implying the paleolatitude to be about 12°. Totally, 13 sites from the Huai Hin Lat formation are included in the calculation of the formation mean direction Dg/Ig = 21.4°/38.1°, kg = 19.5, α95 = 9.6° before and Ds/Is = 43.0°/48.0°, ks = 47.4, α95 = 6.1°, N = 13 after bedding correction. A pre-folding characteristic magnetization is suggested by the positive fold test result derived from the Huai Hin Lat formation, and thus implies a primary remanence of the Norian Stage Upper Triassic rocks. A new Nam Phong formation mean direction derived from 11 sites is Dg/Ig = 36.5°/31.3°, kg = 14.7, α95 = 12.3°before and Ds/Is = 36.4°/37.8°, ks = 68.5, α95 = 5.6°, N = 11 after bedding correction. The two formation mean directions correspond to the magnetic pole positions , Plat./Plon=48.7°N/165.9°E, A95=7.2° and Plat./Plon=55.2°N/178.0°E, A95=5.9°, respectively. A remarkable tectonic movement (~8° southward) of the Indochina block from the age of

  15. Permian charnockites in the Pobeda area: Implications for Tarim mantle plume activity and HT metamorphism in the South Tien Shan range

    Science.gov (United States)

    Loury, Chloé; Rolland, Yann; Lanari, Pierre; Guillot, Stéphane; Bosch, Delphine; Ganino, Clément; Jourdon, Anthony; Petit, Carole; Gallet, Sylvain; Monié, Patrick; Riel, Nicolas

    2018-04-01

    The Permian history of the Central Asian Orogenic belt is marked by large-scale strike-slip faults that reactivate former Paleozoic structures, delineated by widespread alkaline magmatism. The genetic link between the syn-kinematic granitoids emplaced in the Tien Shan range and magmas emplaced within the Tarim Large Igneous Province, and the interaction between this plume and transcurrent tectonics, are still unsolved issues. We investigated the Pobeda massif, in the eastern Kyrgyz Tien Shan, located at the boundary between the Tien Shan range and the Tarim Craton, which exhibits a high-temperature unit. In this unit, Permian magmatism resulted in the emplacement of alkaline charnockites at mid-crustal levels. The primary mineralogical assemblage is nominally anhydrous and made of ortho- and clino-pyroxenes, fayalite, K-feldspar, plagioclase and quartz. These charnockites are associated with partially-molten paragneisses and marbles. Thermobarometry on these rocks indicates that the charnockites emplaced following the intrusion of a melt at a temperature > 1000 °C and pressure of around 6 kbar, corresponding to depth of 20 km. The resulting thermal anomaly triggered the partial melting of paragneisses. Bulk geochemistry including Sr, Nd, Pb and Hf isotopes suggests that charnockites fit into the Tarim Large Igneous Province magmatic series, with minor crustal assimilation. U-Pb ages on zircons of charnockites and surrounding paragneisses indicate that charnockites intruded and triggered partial melting of the gneisses at c. 287, 275 and 265 Ma. 40Ar/39Ar dating on amphibole gives a similar age as the U-Pb age at 276.2 ± 2.0 Ma. 40Ar/39Ar dating on biotite from the Charnockite unit marbles gives ages at ca. 256-265 Ma, which shows that exhumation onset directly follows the HT history, and is tentatively correlated to top-to-the-North thrusting of the Charnockite unit in a transpressive context. Additional 40Ar/39Ar dating on syn-kinematic white micas from an

  16. Climatic change as an argument in the chase for tax money and market intervention. Political economics and scientific uncertainty

    International Nuclear Information System (INIS)

    Benedictus, A.

    2006-01-01

    Based on a political-economical analysis of the stakeholders in the debate on climatic change the author states that the people involved use their arguments on climatic change and its consequences for their own interest and purposes. The precautionary principle is the democratic alibi for politicians and other interest groups to use those interests over the heads of the misguided public [nl

  17. The SOFeX Group

    Science.gov (United States)

    Coale, K. H.

    2002-12-01

    The SOFeX Group is comprised of the following institutions and individuals, all of whose participation resulted in a successful experiment. Moss Landing Marine Laboratories: K. Coale, C. Hunter, M. Gordon, S. Tanner, W. Wang, N. Ladizinsky, D. Cooper, G. Smith, J. Brewster; Monterey Bay Aquarium Research Institute: K. Johnson, F. Chavez, S. Fitzwater, P. Strutton, G. Elrod, Z. Chase, E. Drake, J. Plant; Oregon State University: B. Hales, J. Barth, L.Bandstra, P. Covert, D. Hubbard, J. Jennings, S. Pierce, E. Scholz; Lamont Doherty Earth Observatory: T. Takahashi; Duke University: R. Barber, V. Lance, D. Stube, A. Hilting, M. Hiscock, A. Apprill, C. Van Hilst, ; Virginia Institute of Marine Science: W. Smith, H. Ducklow, L. Delizo, J. Oliver, E. Bailey, J. Peloquin, R. Daniels, J. Bauer; University Of Hawaii: M. Landry, R. Bidigare, S. Brown, N. Cassar, B. Twining, K. Selph, C. Sheridan; NOAA Atlantic Oceanographic and Meteorological Laboratory: R. Wanninkhof, K. Sullivan, C. Neill; University of Miami: F. Millero, X. Zhu, W. Hiscock, V. Koehler, A. Cabrera; University of Calif. Lawrence Berkeley National Laboratory: J. Bishop, T. Wood, C. Guay, P. Lam; Rutgers University: P. Falkowski, Z. Kolber, R. Nicolayson, S. Tozzi, M. Gorbunov, M. Koblizek; University of Massachusets: M. Altabet, M. McIlvan, D. Timothy; New Mexico Tech.: Oliver Wingenter; San Francisco State Univ. - Romberg Tiburon Center: W. Cochlan, J. Herndon; University of Calif. Santa Cruz: R. Kudela, A. Roberts; Univ. of Calif. Santa Barbara: M. Brezinski, J. Jones, M. Demarest; Massachusets Inst. of Technology: S. Chisolm, Z. Johnson; Woods Hole Oceanographic Institute: K. Buesseler, J. Andrews, G. Crossin, S. Pike, J. Tegeder, C. Herbold, K. Mahoney, M.Coggeshell ; University of East Anglia: L. Houghton, L. Goldson, A. Watson, J. Ledwell; Institute of Marine Research, Kiel: Peter Croot; University of Otago: R. Frew, E. Abraham, P. Boyd.

  18. A Novel Pulse-Chase SILAC Strategy Measures Changes in Protein Decay and Synthesis Rates Induced by Perturbation of Proteostasis with an Hsp90 Inhibitor

    Science.gov (United States)

    Fierro-Monti, Ivo; Racle, Julien; Hernandez, Celine; Waridel, Patrice; Hatzimanikatis, Vassily; Quadroni, Manfredo

    2013-01-01

    Standard proteomics methods allow the relative quantitation of levels of thousands of proteins in two or more samples. While such methods are invaluable for defining the variations in protein concentrations which follow the perturbation of a biological system, they do not offer information on the mechanisms underlying such changes. Expanding on previous work [1], we developed a pulse-chase (pc) variant of SILAC (stable isotope labeling by amino acids in cell culture). pcSILAC can quantitate in one experiment and for two conditions the relative levels of proteins newly synthesized in a given time as well as the relative levels of remaining preexisting proteins. We validated the method studying the drug-mediated inhibition of the Hsp90 molecular chaperone, which is known to lead to increased synthesis of stress response proteins as well as the increased decay of Hsp90 “clients”. We showed that pcSILAC can give information on changes in global cellular proteostasis induced by treatment with the inhibitor, which are normally not captured by standard relative quantitation techniques. Furthermore, we have developed a mathematical model and computational framework that uses pcSILAC data to determine degradation constants kd and synthesis rates Vs for proteins in both control and drug-treated cells. The results show that Hsp90 inhibition induced a generalized slowdown of protein synthesis and an increase in protein decay. Treatment with the inhibitor also resulted in widespread protein-specific changes in relative synthesis rates, together with variations in protein decay rates. The latter were more restricted to individual proteins or protein families than the variations in synthesis. Our results establish pcSILAC as a viable workflow for the mechanistic dissection of changes in the proteome which follow perturbations. Data are available via ProteomeXchange with identifier PXD000538. PMID:24312217

  19. A novel pulse-chase SILAC strategy measures changes in protein decay and synthesis rates induced by perturbation of proteostasis with an Hsp90 inhibitor.

    Directory of Open Access Journals (Sweden)

    Ivo Fierro-Monti

    Full Text Available Standard proteomics methods allow the relative quantitation of levels of thousands of proteins in two or more samples. While such methods are invaluable for defining the variations in protein concentrations which follow the perturbation of a biological system, they do not offer information on the mechanisms underlying such changes. Expanding on previous work [1], we developed a pulse-chase (pc variant of SILAC (stable isotope labeling by amino acids in cell culture. pcSILAC can quantitate in one experiment and for two conditions the relative levels of proteins newly synthesized in a given time as well as the relative levels of remaining preexisting proteins. We validated the method studying the drug-mediated inhibition of the Hsp90 molecular chaperone, which is known to lead to increased synthesis of stress response proteins as well as the increased decay of Hsp90 "clients". We showed that pcSILAC can give information on changes in global cellular proteostasis induced by treatment with the inhibitor, which are normally not captured by standard relative quantitation techniques. Furthermore, we have developed a mathematical model and computational framework that uses pcSILAC data to determine degradation constants kd and synthesis rates Vs for proteins in both control and drug-treated cells. The results show that Hsp90 inhibition induced a generalized slowdown of protein synthesis and an increase in protein decay. Treatment with the inhibitor also resulted in widespread protein-specific changes in relative synthesis rates, together with variations in protein decay rates. The latter were more restricted to individual proteins or protein families than the variations in synthesis. Our results establish pcSILAC as a viable workflow for the mechanistic dissection of changes in the proteome which follow perturbations. Data are available via ProteomeXchange with identifier PXD000538.

  20. Chasing the deal with the money: Measuring the required risk premium and expected abnormal returns of private equity funds to maximize their internal rate of return

    Directory of Open Access Journals (Sweden)

    Fernando Scarpati

    2013-09-01

    Full Text Available A number of scholars of private equity (“PE” have attempted to assess the ex-post returns, or performance, of PEs by adopting an ex-post perspective of asset pricing. In doing so a set of phenomena has been recognized that is thought to be specific to the PE sector, such as “money-chasing deal phenomenon” (Gompers and Lerner, 2000 and “performance persistence” (Lerner and Schoar, 2005. However, based on their continuing use of an ex-post perspective, few scholars have paid attention to the possible extent to which these and other PE phenomena may affect expected returns from PE investments. To address this problem this article draws on an ex-ante perspective of investment decision-making in suggesting how a number of drivers and factors of PE phenomena may produce “abnormal returns”, and that each of those drivers and factors should therefore be considered in accurately assessing the required risk premium and expected abnormal returns of PE investments. In making these contributions we examined a private equity investment of a regional PE in Italy and administered a telephone questionnaire to 40 PEs in Italy and the UK and found principally that while size is the most important driver in producing abnormal returns illiquidity alone cannot explain the expected returns of PE investments (cf. Franzoni et al., 2012. Based on our findings we developed a predictive model of PE decision-making that draws on an ex-ante perspective of asset pricing and takes into account PE phenomena and abnormal returns. This model extends the work of Franzoni et al. (2012, Jegadeesh et al. (2009, and Korteweg and Sorensen (2010 who did not consider the possible influence of PE phenomena in decision-making and will also help PE managers in making better-informed decisions.

  1. Prelude of benthic community collapse during the end-Permian mass extinction in siliciclastic offshore sub-basin: Brachiopod evidence from South China

    Science.gov (United States)

    Wu, Huiting; He, Weihong; Weldon, Elizabeth A.

    2018-04-01

    Analysis of the Permian-Triassic palaeocommunities from basinal facies in South China provides an insight into the environmental deterioration occurring in the prelude to the mass extinction event. Quantitative and multivariate analyses on three brachiopod palaeocommunities from the Changhsingian to the earliest Triassic in basinal facies in South China have been undertaken in this study. Although the end-Permian extinction has been proved to be a one-stepped event, ecological warning signals appeared in the palaeocommunities long before the main pulse of the event. A brachiopod palaeocommunity turnover occurred in the upper part of the Clarkina changxingensis Zone, associated with a significant decrease of palaeocommunity diversity and brachiopod body size. During this turnover the dominant genera changed from Fusichonetes and Crurithyris (or/and Paracrurithyris) to the more competitive genus Crurithyris (or/and Paracrurithyris). The brachiopod palaeocommunity turnover was supposed to be triggered by the decreased marine primary productivity and increased volcanic activity. Moreover, such early warning signals are found not only in the deep-water siliceous facies, but also in the shallow-water clastic facies and carbonate rock facies in South China.

  2. Distribution and Diversity of Carboniferous and Permian Colonial Rugose Coral Faunas in Western North America: Clues for Placement of Allochthonous Terranes

    Directory of Open Access Journals (Sweden)

    Calvin H. Stevens

    2012-05-01

    Full Text Available Colonial rugose corals are common in western cratonal North America and in some of the allochthonous terranes, now amalgamated against its western margin. Throughout the Late Paleozoic, the coral faunas in these two different settings were significantly different. Comparisons of these faunas suggest that during the Mississippian the Alexander terrane probably was southwest of Arctic Alaska and the Stikine terrane probably lay west of the southern part of the North American craton. The Cache Creek terrane lay far out in the Paleopacific Ocean. The Pennsylvanian faunas suggest that the Quesnellia and Eastern Klamath terranes were situated southwest of Arctic Alaska and the Alexander terrane was somewhat farther southwest and farther from cratonal North America. The Stikine terrane continued to be positioned west of the southern part of the North American craton. During the Early Permian, terranes with a cratonal faunal aspect may have lain 2000–3000 km west of cratonal North America and latitudinally generally southwest of their present positions. In the Middle Permian these terranes were carried southward relative to the North American craton. Simultaneously the Tethyan Realm expanded eastward.

  3. Juvenile crustal recycling in an accretionary orogen: Insights from contrasting Early Permian granites from central Inner Mongolia, North China

    Science.gov (United States)

    Yuan, Lingling; Zhang, Xiaohui; Xue, Fuhong; Liu, Fulin

    2016-11-01

    Coeval high-K calc-alkaline to alkaline granites constitute important components of post-collisional to post-orogenic igneous suites in most orogenic belts of various ages on Earth and their genesis harbors a key to ascertaining critical geodynamic controls on continental crustal formation and differentiation. This zircon U-Pb dating and geochemical study documents three contrasting Early Permian granites from Erenhot of central Inner Mongolia, eastern Central Asian Orogenic Belt (CAOB) and reveals concurrent high-K calc-alkaline to alkaline granite association derived from successive partial melting of distinct protoliths. The ca. 280 Ma Gancihuduge (GCG) pluton shows a calc-alkaline I-type character, with initial 87Sr/86Sr ratios of 0.7035 to 0.7039, εNd(t) of + 1.87 to + 4.70, zircon εHf(t) of + 8.0 to + 13.2 and δ18O from 7.4 to 8.7‰. The ca. 276 Ma Cailiwusu (CLS) pluton is magnesian and peraluminous, with initial 87Sr/86Sr ratios of 0.7036 to 0.7040, εNd(t) of + 1.9 to + 2.4, zircon εHf(t) of + 6.5 to + 12.1 and δ18O from 9.7 to 10.9‰. These features are consistent with partial melts of mixed sources composed of newly underplated meta-basaltic to -andesitic protoliths and variable supracrustal components, with distinctively higher proportion of the latter in the CLS pluton. By contrast, the ca. 279 Ma Kunduleng (KDL) suite exhibits an A-type magmatic affinity, with typical enrichment in alkalis, Ga, Zr, Nb and Y, εNd(t) of + 2.39 to + 3.55, zircon εHf(t) from + 8.3 to + 12.3 and δ18O values from 6.8 to 7.5‰. These features suggest that they stem from high-temperature fusion of dehydrated K-rich mafic to intermediate protoliths. Besides presenting a snapshot into a stratified crustal architecture in δ18O, these contrasting granites could not only serve as a temporal marker for monitoring post-collisional extension in the aftermath of a retreating subduction zone, but also present spatial magmatic proxy for tracing crustal formation and

  4. Golovkinskii law for prediction of distribution of rock lithotypes of Permian deposits (east part of Russian plate)

    Science.gov (United States)

    Sitdikova, Lyalya; Izotov, Victor; Berthault, Gi; Lalomov, Alexander

    2010-05-01

    Zone of development of upper-permian-kazanian deposits in Volga-Kama petroleum province is the region of facies interrelations law identification. This law is known as the rule of Golovkinskii-Valter. Many details of geological formations relationship in change zones are still discussed. Efforts of analytic expression of Golovkinskii rule for specific regions of its development are very important. We analyzed width of horizons of the Kazanian Stage. They are in zone of facies change of marine gray and red formations of the east part of Russian plate. Results of this analysis were principle for analytic expression of Golovkinskii rule. Percent proportion of main lithological types of these rock formations was also used. We used profile which was based on data from 75 wells. This profile crosses region of development of kazanian deposits from the river Volga to Urals territory. It overpasses main structural and tectonic units of the region: Kazan-Kirov downfold, system of lifted blocks of Tatar Arch and Upper-Kama depression. Kazanian deposits of Kazan-Kirov downfold are represented by typical marine gray carbonate-terrigenous formation. Red formation is deposed within Upper-Kama depression. Zone of these formations relationship is limited to central parts of Tatar Arch. Abrupt fluctuations of content of one rock type in insignificant distance are common. Every rock type has unique features in its distribution on profile. That's why it is possible to study function of dependence of certain rock type content from distance as a sum of regular and chance components. Intensively rising change of proportions of different rock types is presented in the zone of transition from typical marine deposits to red deposits. So trends of variation of percent content (y) of main rock lithotypes depending on distance (x) can be described by simple difference equations: dy = -kdx, for rocks of marine gray formation. dy = k(M-y)dx, for rocks of red formation. M - mathematical

  5. A geochemical view into continental palaeotemperatures of the end-Permian using oxygen and hydrogen isotope composition of secondary silica in chert rubble breccia: Kaibab Formation, Grand Canyon (USA).

    Science.gov (United States)

    Kenny, Ray

    2018-01-16

    The upper carbonate member of the Kaibab Formation in northern Arizona (USA) was subaerially exposed during the end Permian and contains fractured and zoned chert rubble lag deposits typical of karst topography. The karst chert rubble has secondary (authigenic) silica precipitates suitable for estimating continental weathering temperatures during the end Permian karst event. New oxygen and hydrogen isotope ratios of secondary silica precipitates in the residual rubble breccia: (1) yield continental palaeotemperature estimates between 17 and 22 °C; and, (2) indicate that meteoric water played a role in the crystallization history of the secondary silica. The continental palaeotemperatures presented herein are broadly consistent with a global mean temperature estimate of 18.2 °C for the latest Permian derived from published climate system models. Few data sets are presently available that allow even approximate quantitative estimates of regional continental palaeotemperatures. These data provide a basis for better understanding the end Permian palaeoclimate at a seasonally-tropical latitude along the western shoreline of Pangaea.

  6. Record of palaeoenvironmental changes in a Lower Permian organic-rich lacustrine succession: Integrated sedimentological and geochemical study of the Rudník member, Krkonoše Piedmont Basin, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Martínek, K.; Blecha, M.; Daněk, V.; Franců, J.; Hladíková, J.; Johnová, R.; Uličný, David

    2006-01-01

    Roč. 230, 1/2 (2006), s. 85-128 ISSN 0031-0182 R&D Projects: GA ČR GA205/94/0692 Institutional research plan: CEZ:AV0Z30120515 Keywords : Lower Permian * Bohemian Massif * lacustrine facies Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.822, year: 2006

  7. Permian Circulipuncturites discinisporis Labaindera, Wang, Zhang, Bek et Pfefferkorn gen. et spec. nov. (formerly Discinispora) from Cina, an ichnotaxon of a punch-and-sucking insect on Noeggerathialean spores

    Czech Academy of Sciences Publication Activity Database

    Wang, J.; Labandeira, C. C.; Zhang, G.; Bek, Jiří; Pfefferkorn, H. W.

    2009-01-01

    Roč. 156, 3/4 (2009), s. 277-282 ISSN 0034-6667 R&D Projects: GA AV ČR IAA301110701 Institutional research plan: CEZ:AV0Z30130516 Keywords : noeggerathiales * in situ spores * insect damage * ichnotaxon * Permian Subject RIV: EF - Botanics Impact factor: 2.145, year: 2009

  8. Oxygen and Carbon Isotopic Composition of Carbonate Rocks of the Permian Qixia Formation, Sichuan Basin: Thermal Effects of Emeishan Basalt

    Directory of Open Access Journals (Sweden)

    Keke Huang

    2016-01-01

    Full Text Available The late Permian thermal events related to Emeishan Basalt has made a great impact on the underlying carbonate rock properties in the western margin of the Yangtze Platform. In this paper, we investigate the carbon and oxygen isotopic composition of the Qixia Formation carbonates from two sections: the Qiaoting Section in the northeastern part of the Sichuan Basin and the Changjianggou Section at the northwestern edge of the Basin. The data reveal that: (i Samples from Qiaoting section show a relatively narrow range of δ13C and δ18O, varying from 2.7‰ to 5.2‰ with an average of 4.2‰, and -3.8‰ to -7.8‰ with an average of -5.4‰, respectively. In contrast, Samples from Changjianggou section exhibit larger magnitude of variation in δ13C and δ18O, ranging from -1‰ to 3.8‰ with an average of 1.5‰, and -2.1 to -9.2‰, with an average of -6.0‰ respectively; (ii δ13C and δ18O records in carbonates from Qiaoting section are similar to those of Middle Permian seawater whereas carbonates from the Changjianggou section are depleted in 13C and 18O compared to contemporary seawater; (iii On the basis of combined petrographic and paleo-heat flow evidence, the lower carbon and oxygen isotopic composition of the carbonates from the Changjianggou section are interpreted to be the results of thermal effects of Emeishan Basalt because of its proximity to the eruption center of the basalt. The high temperature reduced the δ18O values of the carbonates and forced the organic matter to mature at an early stage, thus producing 13C-enriched carbon dioxide to participate in the formation of carbonates.     Composición Isotópica de Oxígeno y Carbón en Rocas de Carbonato de la Formación de Edad Pérmica Qixia, en la Cuenca de Sichuan: Efectos Térmicos del Basalto Emeishan   Resumen Los eventos térmicos del Pérmico tardío relacionados con el Basalto Emeishan han tenido un gran impacto en las propiedades de las rocas de carbonato

  9. Deciphering the diagenetic alteration degree in thrombolites across the Permian-Triassic boundary and the evaluation of REY as a proxy of palaeoseawater

    Science.gov (United States)

    Li, Rong

    2017-10-01

    The thrombolites across the Permian-Triassic boundary (PTB) are widely distributed in South China. In order to examine the utility of rare earth element and yttrium (REY) in the thrombolites as a proxy of palaeoseawater, the petrographic and geochemical (Sr, Mn, Fe, REY, δ13C, δ18O) features of thrombolites from Cili and Taiping sections are comparatively studied to determine the diagenetic alteration degrees of the thrombolites and the impact of diagenesis on REY concentrations and distribution patterns. The thrombolites from Cili section, digitate in mesoscopic morphology, are latest Permian in age. In contrast, most of the thrombolites in Taiping section are mottled and formed in the earliest Triassic. The variation in thrombolite morphology across the PTB is probably related to increasing amount of metazoan and increasing intensity of bioturbation after the end-Permian mass extinction. Compared to the thrombolites from Taiping section, those from Cili section underwent more extensive diagenetic alteration, which are characterized by more dolomitic content, lower Sr concentrations, more negative δ18O values, and higher Mn/Sr ratios. The REY concentrations are higher in the thrombolites from Taiping section (5-303 ppm, average 48 ppm) than in the thrombolites from Cili section (17-34 ppm, average 25 ppm). Shale-normalized REY distribution patterns of the thrombolites from both sites are similar to those of oxygenated seawater, which are characterized by positive La anomalies (Pr/Pr∗ = 1.1-1.5), negative Ce anomalies (Ce/Ce∗ = 0.2-0.9), and light rare earth element (LREE) depletion. The preserved seawater like REY distribution pattern indicates that diagenesis did not alter the REY distribution patterns. The thrombolite samples from Cili section, compared to the counterparts from Taiping, have less positive La anomaly and less negative Ce anomaly. For the thrombolites from Cili section, a positive correlation exists between Ce anomaly and siliciclastic

  10. Inclination Shallowing in the Permian/Triassic Boundary Sedimentary Sections of the East European Platform: the New Paleomagnetic Pole and its Significance for GAD Hypothesis

    Science.gov (United States)

    Veselovskiy, R. V.; Fetisova, A. M.; Balabanov, Y.

    2017-12-01

    One of the key challenges which are traditionally encountered in studying the paleomagnetism of terrigenous sedimentary strata is the necessity to allow for the effect of shallowing of paleomagnetic inclinations which takes place under the compaction of the sediment at the early stages of diagenesis and most clearly manifests itself in the case of midlatitude sedimentation. Traditionally, estimating the coefficient of inclination flattening (f) implies routine re-deposition experiments and studying their magnetic anisotropy (Kodama, 2012), which is not possible in every standard paleomagnetic laboratory. The Elongation-Inclination (E/I) statistical method for estimating the coefficient of inclination shallowing, which was recently suggested in (Tauxe and Kent, 2004), does not require the investigation of the rock material in a specially equipped laboratory but toughens the requirements on the paleomagnetic data and, primarily, regarding the volume of the data, which significantly restricts the possibilities of the post factum estimation and correction for inclination shallowing. We present the results of the paleomagnetic reinvestigation of the some key sections of the Upper Permian and Lower Triassic rocks located on the East European Platform. The obtained paleomagnetic data allowed us to estimate the coefficient of inclination shallowing by the E/I method and calculate a new P-Tr paleomagnetic pole for Europe. The absence of a statistically significant difference between the mean Siberian, European and North American Permian-Triassic paleomagnetic poles allow us to conclude that 252 Ma the configuration of the Earth's magnetic field was predominantly dipole. We believe that the assumption of the non-dipolarity of the geomagnetic field at the Permian-Triassic boundary, which has been repeatedly discussed in recent decades (Van der Voo and Torsvik, 2001; Bazhenov and Shatsillo, 2010; Veselovskiy and Pavlov, 2006), arose due to the failure to take into account the

  11. Extending the Sensitivity of Paleomagnetic Techniques: Magnetostratigraphy of Weakly- Magnetized, Organic-Rich Black Limestone from the Permian of Japan

    Science.gov (United States)

    Kirschvink, J. L.; Isozaki, Y.

    2007-12-01

    Despite their importance for biostratigraphy, bituminous, organic-rich limestone has rarely yielded reliable paleomagnetic results, principally due to the weak magnetization levels encountered; NRMs for such samples often start with moments below 10-10Am2 (10-7 emu), and they become unmeasurable or unstable rapidly upon demagnetization. Recently, we have developed a fairly simple and inexpensive automation system for standard paleomagnetic and rock magnetic measurements that has the additional benefit of using an extremely low-noise sample holder. A vacuum pick-and-put system holds samples at the end a thin-walled quartz-glass tube, moving them between a measurement queue and the sense region of a vertically-aligned superconducting rock magnetometer. The system minimizes the amount of extraneous material introduced into the magnetometer's sense region. With frequent cleaning in strong acid, the glass holder system is capable of reliably measuring samples with moments below 1 pAm2 (10-9 emu), on a DC-SQuID magnetometer system with stable instrument noise of a few hundred fAm2. Signal averaging and clean-lab handling techniques are often needed to achieve this sensitivity, however. To test this system, we collected a series of densely-spaced samples for magnetostratigraphy from two sections in the Middle-Late Permian limestone at Kamura in Kyushu, Japan, which is the remnant of lagoonal sediments formed on an oceanic island atoll (Isozaki et al., 2007). According to fusulinids, the Saraito section spans Wordian time, which should be near the end of the Kiaman Reversed superchron. Similarly, strata at the Kamura section cover late Capitanian to early Wuchiapingian time, which should display a shift from predominantly Normal to Reversed magnetization. Raman spectroscopy suggests no appreciable heating. NRM intensities of the samples range generally between 10-10 and 10-11 Am2, with little change in the vectors either upon low-temperature cycling or alternating

  12. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  13. Mantle contribution and tectonic transition in the Aqishan-Yamansu Belt, Eastern Tianshan, NW China: Insights from geochronology and geochemistry of Early Carboniferous to Early Permian felsic intrusions

    Science.gov (United States)

    Du, Long; Long, Xiaoping; Yuan, Chao; Zhang, Yunying; Huang, Zongying; Wang, Xinyu; Yang, Yueheng

    2018-04-01

    Late Paleozoic is a key period for the accretion and collision of the southern Central Asian Orogenic Belt (CAOB). Here, we present new zircon U-Pb ages, whole-rock geochemistry and Sr-Nd isotopic compositions for four Late Paleozoic felsic plutons in Eastern Tianshan (or Tienshan in some literatures) in order to constrain the tectonic evolution of the southern CAOB. The granodioritic pluton and its dioritic enclaves were synchronously formed in the Early Carboniferous (336 ± 3 Ma and 335 ± 2 Ma, respectively). These rocks are depleted in Nb, Ta and Ti, and enriched in Rb, Ba, Th and U related to the primitive mantle, which show typical features of arc rocks. They both have similar Sr-Nd isotopic ratios to those granitic rocks from the eastern Central Tianshan Block and have the latest Mesoproterozoic two stage Nd model ages (TDM2) (1111-1195 Ma for the granodioritic pluton and 1104-1108 Ma for the enclaves, respectively), indicating that their source magmas may have been derived from the Mesoproterozoic crust. The albitophyric pluton was also emplaced in the Early Carboniferous (333 ± 3 Ma). Rocks of this pluton have similar εNd(t) values (-0.69 to -0.37) and TDM2 ages (1135-1161 Ma) to those of the granodioritic rocks, suggest similar crustal source for both types of rocks. In contrast, the K-feldspar granitic and monzonitic plutons were emplaced in the Early Permian (292 ± 3 Ma and 281 ± 2 Ma, respectively). Samples of the K-feldspar granitic pluton have high K2O + Na2O, FeO/MgO, Ga/Al, HFSE (e.g., Zr and Hf) and low CaO, Sr and Ba, exhibiting characteristics of A2-type granites, which probably emplaced in a post-collisional extension environment. They have higher εNd(t) values (+2.77 to +3.27) and more juvenile TDM2 ages (799-841 Ma) than the Early Carboniferous plutons, suggesting that they were derived from relatively younger crustal sources. The monzonitic granites are metaluminous to weakly peraluminous with A/CNK ranging from 0.93 to 1.05, and have

  14. Petrographic report on clay-rich samples from Permian Unit 4 salt, G. Friemel No. 1 well, Palo Duro Basin, Deaf Smith County, Texas: unanalyzed data

    International Nuclear Information System (INIS)

    Fukui, L.M.

    1983-09-01

    This report presents the results of mineralogic and petrographic analyses performed on five samples of clay-rich rock from salt-bearing Permian strata sampled by drill core from G. Friemel No. 1 Well, Deaf Smith County, Texas. Five samples of clay-rich rock from depths of about 2457, 2458, 2521, 2548, and 2568 feet were analyzed to determine the amounts of soluble phase (halite) and the amounts and mineralogy of the insoluble phases. The amounts of halite found were 59, 79, 47, 40, and 4 weight percent, respectively, for the samples. The insoluble minerals are predominately clay (20 to 60 volume percent) and anhydrite (up to 17 volume percent), with minor (about 1.0%) and trace amounts of quartz, dolomite, muscovite, and gypsum. The clays include illite, chlorite, and interstratified chlorite-smectite. The results presented in this petrographic report are descriptive, uninterpreted data. 2 references, 7 tables

  15. U.S. Geological Survey input-data forms for the assessment of the Spraberry Formation of the Midland Basin, Permian Basin Province, Texas, 2017

    Science.gov (United States)

    Marra, Kristen R.

    2017-10-24

    In 2017, the U.S. Geological Survey (USGS) completed an updated assessment of undiscovered, technically recoverable oil and gas resources in the Spraberry Formation of the Midland Basin (Permian Basin Province) in southwestern Texas (Marra and others, 2017). The Spraberry Formation was assessed using both the standard continuous (unconventional) and conventional methodologies established by the USGS for three assessment units (AUs): (1) Lower Spraberry Continuous Oil Trend AU, (2) Middle Spraberry Continuous Oil Trend AU, and (3) Northern Spraberry Conventional Oil AU. The revised assessment resulted in total estimated mean resources of 4,245 million barrels of oil, 3,112 billion cubic feet of gas, and 311 million barrels of natural gas liquids. The purpose of this report is to provide supplemental documentation of the input parameters used in the USGS 2017 Spraberry Formation assessment.

  16. Discovery of abundant cellulose microfibers encased in 250 Ma Permian halite: a macromolecular target in the search for life on other planets.

    Science.gov (United States)

    Griffith, Jack D; Willcox, Smaranda; Powers, Dennis W; Nelson, Roger; Baxter, Bonnie K

    2008-04-01

    In this study, we utilized transmission electron microscopy to examine the contents of fluid inclusions in halite (NaCl) and solid halite crystals collected 650 m below the surface from the Late Permian Salado Formation in southeastern New Mexico (USA). The halite has been isolated from contaminating groundwater since deposition approximately 250 Ma ago. We show that abundant cellulose microfibers are present in the halite and appear remarkably intact. The cellulose is in the form of 5 nm microfibers as well as composite ropes and mats, and was identified by resistance to 0.5 N NaOH treatment and susceptibility to cellulase enzyme treatment. These cellulose microfibers represent the oldest native biological macromolecules to have been directly isolated, examined biochemically, and visualized (without growth or replication) to date. This discovery points to cellulose as an ideal macromolecular target in the search for life on other planets in our Solar System.

  17. Group Flow and Group Genius

    Science.gov (United States)

    Sawyer, Keith

    2015-01-01

    Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

  18. Applications and limitations of micro-XCT imaging in the studies of Permian radiolarians: A new genus with bi-polar main spines

    Directory of Open Access Journals (Sweden)

    Yifan Xiao

    2017-09-01

    Full Text Available Microfocus X-ray Computed Tomography (micro-XCT has been employed recently in radiolarian studies, though so far primarily to generate high quality tomographic images. Although micro-XCT technique cannot always produce high-quality tomographic images, it frequently can provide valuable information on the internal structure of spongy polycystines. Here we employ micro-XCT to understand internal skeletal structures of several Permian specimens of polycystine radiolarians. Structural inferences from micro-XCT images are compared to images of the same specimens made with SEM and transmitted light microscopy (TLM. The utility of micro-XCT for imaging internal structures is first confirmed by examining the spongy, flat, four-spined species Tetraspongodiscus stauracanthus. Micro-XCT method is then used to examine the internal structures of a spherical to elliptical polycystine with two bi-polar main spines, Dalongicaepa bipolaris Xiao and Suzuki gen. et sp. nov., from the Dalong Formation (Changhsingian of South China. The new genus is characterized by four to seven densely concentric shells with a large spherical hollow in the center and two cylindrical spines at both poles of the cortical shell, and belongs to the family Spongotortilispinidae. Spherical to elliptical polycystines with bi-polar main spines are similar in external appearance, and their phylogenetic relationships are only determinable by examination of the internal structures. We therefore analyzed all Permian and Mesozoic spherical to elliptical polycystines with bi-polar main spines showing internal structures, using cluster analysis to measure similarity. The results show distinctive differences in internal structures and suggest that family level relationships should be revised in the future.

  19. High sedimentation rates in the Early Triassic after latest Permian mass extinction: Carbonate production is main factor in non-Arctic regions

    Science.gov (United States)

    Horacek, Micha; Brandner, Rainer

    2016-04-01

    A substantial change in sedimentation rates towards higher values has been documented from the Late Permian to the Lower Triassic. Although it is assumed and also has been shown that the deposition of siliciclastic material increased in the Lower Triassic due to stronger erosion because of loss of land cover and increased chemical and physical weathering with extreme climate warming, the main sediment production occurred by marine carbonate production. Still, carbonate production might have been significantly influenced by weathering and erosion in the hinterland, as the transport of dust by storms into the ocean water probably was a main nutrient source for microbial carbonate producers, because "normal" nutrient supply by ocean circulation, i. e. upwelling was strongly reduced due to the elevated temperatures resulting in water-column stratification . Sediment accumulation was also clearly influenced by the paleo-geographic and latitudinal position, with lower carbonate production and sedimentation rates in moderate latitudes. The existence of a "boundary clay" and microbial carbonate mounds and layers in the immediate aftermath of the latest Permian mass extinction points towards a development from a short-timed acid ocean water - resulting in a carbonate production gap and the deposition of the boundary clay towards the deposition of the microbial mounds and layers due to the microbial production of micro-environments with higher alkalinity allowing the production of carbonate. After the return of the ocean water to normal alkalinity planktic production of carbonate resulted in a very high sedimentation rate, especially taking into account the absence of carbonate producing eukaryotic algae and animals.

  20. Nonmarine time-stratigraphy in a rift setting: An example from the Mid-Permian lower Quanzijie low-order cycle Bogda Mountains, NW China

    Directory of Open Access Journals (Sweden)

    Jonathan Obrist-Farner

    2015-01-01

    Full Text Available Sedimentological and stratigraphic studies of seven stratigraphic sections of Permian Hongyanchi (HYC and Quanzijie (QZJ low-order cycles (LCs in the Tarlong-Taodonggou half graben and Dalongkou area in Bogda Mountains, NW China, demonstrate effective approaches and methodology in cyclo- and time-stratigraphic analyses of complex fluvial-lacustrine deposits in an intracontinental rift setting. A new synchronous stratigraphic unit, the lower QZJ LC is defined. The lower and upper boundaries of this cycle include a regionally correlative disconformity, erosional unconformity, and conformity, across which significant and abrupt changes in palaeoenvironments and tectonic and climatic conditions occurred. The lower boundary is an erosional unconformity and disconformity with a high-relief topography that juxtaposes lacustrine deposits of the underlying HYC LC with the overlying meandering stream deposits of the lower QZJ LC, and was caused by a regional tectonic uplift. The upper boundary is a disconformity and local erosional unconformity and conformity, juxtaposing stacked paleosols developed on fluvial sediments with overlying fluvial and loessial deposits of the upper QZJ LC. The paleosols indicate landscape stability and a prolonged period of subaerial exposure and minimal deposition and suggest that climatic conditions were semi-arid with strong precipitation seasonality in the Tarlong-Taodonggou half graben and subhumid in the Dalongkou area. The fluvial-loessial deposits indicate a renewed tectonic uplift and a change in the atmospheric circulation pattern. The newly-defined lower QZJ LC facilitates accurate palaeogeographic reconstruction in the study area during a period of major tectonic and climatic changes. The interpreted tectonic and climatic conditions provide a critical data point in the mid-latitude east coast of NE Pangea during the Mid-Permian icehouse-hothouse transition. The results demonstrate that a process-response approach

  1. Reassessment of petrogenesis of Carboniferous–Early Permian rift-related volcanic rocks in the Chinese Tianshan and its neighboring areas

    Directory of Open Access Journals (Sweden)

    Linqi Xia

    2012-07-01

    Full Text Available The Carboniferous−Early Permian rift-related volcanic successions, covering large areas in the Chinese Tianshan and its adjacent areas, make up a newly recognized important Phanerozoic large igneous province in the world, which can be further divided into two sub-provinces: Tianshan and Tarim. The regional unconformity of Lower Carboniferous upon basement or pre-Carboniferous rocks, the ages (360–351 Ma of the youngest ophiolite and the peak of subduction metamorphism of high pressure–low temperature metamorphic belt and the occurrence of Ni-Cu-bearing mafic-ultramafic intrusion with age of ∼352 Ma and A-type granite with age of ∼358 Ma reveal that the final closure of the Paleo-Asian Ocean might take place in the Early Mississippian. Our summation shows that at least four criteria, being normally used to identify ancient asthenosphere upwelling (or mantle plumes, are met for this large igneous province: (1 surface uplift prior to magmatism; (2 being associated with continental rifting and breakup events; (3 chemical characteristics of asthenosphere (or plume derived basalts; (4 close links to large-scale mineralization and the uncontaminated basalts, being analogous to those of many “ore-bearing” large igneous provinces, display Sr-Nd isotopic variations between plume and EM1 geochemical signatures. These suggest that a Carboniferous asthenosphere upwelling and an Early Permian plume played the central role in the generation of the Tianshan–Tarim (central Asia large igneous province.

  2. Geochemical Variability and the Potential for Beneficial Use of Waste Water Coproduced with Oil from Permian Basin of the Southwest USA

    Science.gov (United States)

    Khan, N. A.; Holguin, F. O.; Xu, P.; Engle, M.; Dungan, B.; Hunter, B.; Carroll, K. C.

    2014-12-01

    The U.S. generates 21 billion barrels/year of coproduced water from oil and gas exploration, which is generally considered waste water. Growth in unconventional oil and gas production has spurred interest in beneficial uses of produced water, especially in arid regions such as the Permian Basin of Texas and New Mexico, the largest U.S. tight oil producer. Produced waters have variable chemistries, but generally contain high levels of organics and salts. In order to evaluate the environmental impact, treatment, and reuse potential, there is a need to characterize the compositional variability of produced water. In the present study, produced water samples were collected from 12 wells across the Permian Basin. Compositional analyses including coupled gas chromatography-time of flight-mass spectrometry and inductively coupled plasma-optical emission spectroscopy were conducted. The samples show elevated benzene, ethylbenzene, toluene, xylene, alkyl benzenes, propyl-benzene, and naphthalene compared to other heteroaromatics; they also contain complex hydrocarbon compounds containing oxygen, nitrogen, and sulfur. Van Krevelen diagrams show an increase in the concentration of heteroaromatic hydrocarbons with increasing well depth. The salinity, dominated by sodium-chloride, also increases with depth, ranging from 37-150 g/L TDS. Depth of wells (or producing formation) is a primary control on predicting water quality for treatment and beneficial use. Our results suggest that partial treatment by removing suspended solids and organic contaminants would support some beneficial uses such as onsite reuse, bioenergy production, and other industrial uses. Due to the high salinity, conventional desalination processes are not applicable or very costly, making beneficial uses requiring low salinity not feasible.

  3. DURATION OF GRANITOID MAGMATISM IN PERIPHERAL PARTS OF LARGE IGNEOUS PROVINCES (BASED ON 40AR/39AR ISOTOPIC STUDIES OF ALTAI PERMIAN-TRIASSIC GRANITOIDS

    Directory of Open Access Journals (Sweden)

    O. A. Gavryushkina

    2017-01-01

    Full Text Available In large igneous provinces (LIP of fold areas, granitoid rocks are dominant, while mantle-derivated rocks play a subordinate role in rock formation. If magma emissions are impulsive, it may take 25–30 million years for a LIP to form and take shape. In this paper, we present the results of 40Ar/39Ar isotopic studies of Permian-Triassic grani­toids in the Altai region, Russia, and clarify the evolution of this region located at the periphery of the Siberian LIP. These granitoids are very diverse and differ not only in their rock set, but also in the composition features. In the study region, the granodiorite-granite and granite-leucogranite association with the characteristics of I- and S-types as well rare metal ore-bearing leucogranites are observed along with gabbro- and syenite-granite series, including mafic and intermediate rocks with the A2-type geochemical features. The 40Ar/39Ar data obtained in our study suggest that most of the studied granitoids intruded within a short period of time, 254–247 Ma. This timeline is closely related to the formation of granitoids in theKuznetsk basin and dolerite dikes in the Terekta complex (251–248 and 255±5 Ma, respectively, as well as intrusions of lamproite and lamprophyre dikes of the Chuya complex (245–242 and 237–235 Ma. Thus, we conclude that the Altai Permian-Triassic granitoids are varied mainly due to the evolution of mafic magmatism.

  4. An Early Permian epithermal gold system in the Tulasu Basin in North Xinjiang, NW China: Constraints from in situ oxygen-sulfur isotopes and geochronology

    Science.gov (United States)

    Dong, Leilei; Wan, Bo; Deng, Chen; Cai, Keda; Xiao, Wenjiao

    2018-03-01

    The Axi and Jingxi-Yelmand gold deposits, being the largest gold deposits in the Chinese North Tianshan, NW China, are located ca. l0 km apart in the Tulasu Basin, and are hosted by the Late Devonian - Early Carboniferous Dahalajunshan Formation. In situ LA-ICP-MS titanium analyses on quartz from the Axi and Jingxi-Yelmand deposits are broadly identical. Accordingly, the calculated ore-forming temperatures by Ti-in-quartz thermometer give average temperatures of 279 °C and 294 °C, respectively. Results of in situ SIMS analyses of oxygen and sulfur isotopes on quartz and pyrite from these two deposits are similar. Temperature-corrected fluids of the Axi deposit have δ18O values of 2.6-8.1‰ and δ34S values of 0.8-2.4‰, whereas the fluids of the Jingxi-Yelmand deposit have δ18O of 6.4-8.9‰ and δ34S of -0.4 to 4.0‰. The oxygen and sulfur isotopes from the two deposits indicate a magmatic origin. LA-ICP-MS zircon U-Pb ages of Aqialehe Formation sandstone provided a lower limit for the mineralization timing of the Axi deposit (288 Ma). In situ SIMS U-Pb analyses on entrapped zircon (297 Ma) and newly recognized 284.5 Ma columnar rhyolite implies that the Jingxi-Yelmand deposit formed in the Early Permian. Based on the magmatic affinity of the ore fluids, similar age and ore-formation temperatures, we propose that the Axi and Jingxi-Yelmand deposits comprise an epithermal gold system, which was driven by the same Permian magma in the Tulasu Basin. The ore geological features together with our new results indicate that the Axi and Jingxi-Yelmand deposits are intermediate and high sulfidation type epithermal deposits, respectively.

  5. The elemental geochemistry of Lower Triassic shallow-marine carbonates from central Saudi Arabia: Implications for redox conditions in the immediate aftermath of the latest Permian mass extinction

    Science.gov (United States)

    Eltom, Hassan A.; Abdullatif, Osman M.; Babalola, Lamidi O.

    2018-03-01

    The southern margin of the Tethys Ocean was occupied by a broad, shallow continental shelf during the Permian-Triassic boundary interval, with the area of present-day Saudi Arabia located from 10° to 30° south of the paleo-equator. The strata deposited in modern Saudi Arabia in the aftermath of the latest Permian mass extinction (LPME) are dominated by oolitic microbialite limestone (OML), which are overlain by skeletal oolitic limestones (SOL) capped by dolostones and dolomitic limestones (DDL). This succession reflects changes in depositional setting, which can be potentially tied to redox conditions using redox sensitive trace elements and rare earth elements (REEs). Statistical analyses reveals that trace elements and REEs are associated with detrital material, and possibly with diagenetic minerals as well. Proxies such as the Y/Ho, Pr/Pr*, Smn/Ybn, Lan/Smn and Lan/Ybn ratios indicate that REEs do not record a seawater-like pattern, and cannot be used as redox indicator. The presence of a normal marine fauna implies oxic conditions during deposition of the DDL and SOL units. However, the OML unit, which represents the immediate aftermath of LPME, lacks both a normal marine fauna and reliable geochemical signals, making it difficult to infer redox conditions in the depositional environment. Similar to published data from sections that reflect shallow marine condition in the LPME of the Tethys Ocean, chemical index of alteration values are consistently high throughout the study succession, suggesting globally intense chemical weathering in the aftermath of the LPME. As a result, geochemical redox proxies in shallow marine carbonates of the Tethys Ocean are likely to be contaminated by detrital material that have been generated by chemical weathering, and thus, other methods are required to determine depositional redox conditions.

  6. Chameleon Chasing II: A Replication.

    Science.gov (United States)

    Newsom, Doug A.; And Others

    1993-01-01

    Replicates a 1972 survey of students, educators, and Public Relations Society of America members regarding who the public relations counselor really serves. Finds that, in 1992, most respondents thought primary responsibility was to the client, then to the client's relevant publics, then to self, then to society, and finally to media. Compares…

  7. Biological Collections: Chasing the Ideal

    Science.gov (United States)

    Kamenski, P. A.; Sazonov, A. E.; Fedyanin, A. A.; Sadovnichy, V. A.

    2016-01-01

    This article is based on the results of an analysis of existing biological collections in Russia and abroad set up in the framework of the project “Scientific Basis of the National Biobank –Depository of Living Systems” by M.V. Lomonosov Moscow State University [1]. PMID:27437135

  8. CHASE Survey of Technology Needs

    Science.gov (United States)

    2017-03-01

    layers (system and application services) for some existing and emerging application domains and devices, for example, smartphones , cyber physical ...Also, this study shows that embedded systems security and cyber physical systems security is an emerging area of interest and importance. Keywords...hardware security; counterfeits; hardware Trojans; reverse engineering; embedded systems; cyber physical systems security. 1. Introduction Over the

  9. Captain Cook Chased a Chook

    Directory of Open Access Journals (Sweden)

    Katrina Schlunke

    2011-04-01

    Full Text Available How can we write the contemporary 'histories' of Captain Cook when they include such textual and material diversity? When that diversity ranges from children's rhymes to convenience stores as well as journals now claimed as iconic documents of the enlightenment? How might the insights of Bruno Latour into how the 'experimental' is produced in the laboratory be helpful in showing how Cook is produced in a settler culture? How does revealing the 'experimental' (the material and textual ethnography of history show us new ways of 'doing' history that engages with its textual as well as its material diversity.

  10. Additive opportunistic capture explains group hunting benefits in African wild dogs.

    Science.gov (United States)

    Hubel, Tatjana Y; Myatt, Julia P; Jordan, Neil R; Dewhirst, Oliver P; McNutt, J Weldon; Wilson, Alan M

    2016-03-29

    African wild dogs (Lycaon pictus) are described as highly collaborative endurance pursuit hunters based on observations derived primarily from the grass plains of East Africa. However, the remaining population of this endangered species mainly occupies mixed woodland savannah where hunting strategies appear to differ from those previously described. We used high-resolution GPS and inertial technology to record fine-scale movement of all members of a single pack of six adult African wild dogs in northern Botswana. The dogs used multiple short-distance hunting attempts with a low individual kill rate (15.5%), but high group feeding rate due to the sharing of prey. Use of high-level cooperative chase strategies (coordination and collaboration) was not recorded. In the mixed woodland habitats typical of their current range, simultaneous, opportunistic, short-distance chasing by dogs pursuing multiple prey (rather than long collaborative pursuits of single prey by multiple individuals) could be the key to their relative success in these habitats.

  11. États de contraintes et mécanismes d'ouverture et de fermeture des bassins permiens du Maroc hercynien. L'exemple des bassins des Jebilet et des RéhamnaStates of stresses and opening/closing mechanisms of the Permian basins in Hercynian Morocco. The example of the Jebilet and Réhamna Basins

    Science.gov (United States)

    Saidi, Amal; Tahiri, Abdelfatah; Ait Brahim, Lahcen; Saidi, Maraim

    The fracturing analysis in the Permian basins of Jebilet and Rehamna (Hercynian Morocco) and the underlying terranes allowed us to suggest a model for their opening. Three tectonic episodes are distinguished: a transtensional episode NNE-SSW-trending (Permian I), occurring during the opening along sinistral wrench faults N70-110-trending, associated with synsedimentary normal faults; a transpressive episode ESE-WNW-trending (Permian II), initiating the closure, the normal faults playing back reverse faults and the N70 trending faults dextral wrench faults; a compressional episode NNW-SSE (post-Permian, ante-Triassic), accentuating the closure and the deformation and putting an end to the Tardi-Hercynian compressive movements. To cite this article: A. Saidi et al., C. R. Geoscience 334 (2002) 221-226.

  12. Permutation groups

    CERN Document Server

    Passman, Donald S

    2012-01-01

    This volume by a prominent authority on permutation groups consists of lecture notes that provide a self-contained account of distinct classification theorems. A ready source of frequently quoted but usually inaccessible theorems, it is ideally suited for professional group theorists as well as students with a solid background in modern algebra.The three-part treatment begins with an introductory chapter and advances to an economical development of the tools of basic group theory, including group extensions, transfer theorems, and group representations and characters. The final chapter feature

  13. Evidence in Variscan Corsica of a brief and voluminous Late Carboniferous to Early Permian volcanic-plutonic event contemporaneous with a high-temperature/low-pressure metamorphic peak in the lower crust

    International Nuclear Information System (INIS)

    Rossi, Philippe; Cocherie, Alain; Fanning, C. Mark

    2015-01-01

    The U2 group of plutonic rocks constituting the main exposed part of the Corsica-Sardinia batholith (CSB) was emplaced from 308 to 275 Ma (the early Visean U1 group of Mg-K intrusions is not considered here). Field evidence earlier established volcanic-plutonic relationships in the U2 group of calc-alkaline intrusions of the CSB, though detailed chronological data were still lacking. Large outcrops of U2 volcanic formations are restricted to the less eroded zone north-west of the Porto-Ponte Leccia line in Corsica, but volcanic and volcano-sedimentary formations were widely eroded elsewhere since Permian times. They probably covered most of the batholith before the Miocene, as testified by the volcanic nature of the pebbles that form much of the Early Miocene conglomerates of eastern Corsica. U-Pb zircon dating (SHRIMP) was used for deciphering the chronology and duration of different volcanic pulses and for better estimating the time overlap between plutonic and volcanic rock emplacement in the CSB. The obtained ages fit well with field data, showing that most of the U2 and U3 volcanic formations were emplaced within a brief time span of roughly 15 m.y., from 293 to 278 Ma, coeval with most U2 monzo-granodiorites and leuco-monzo-granites (295-280 Ma), alkaline U3 complexes (about 288 Ma), and mafic-ultramafic tholeiitic complexes (295-275 Ma). The same chronological link between deep-seated magma chambers and eruptions was identified in the Pyrenees. These results correlate with U-Pb zircon dating of HT-LP granulites from the Variscan deep crust exhumed along the 'European' margin of the thinned Tethys margin in Corsica and Calabria. Here, the peak of the low-pressure/high-temperature metamorphism was dated at about 285-280 Ma. Our results throw light on the condition of magma production during the orogenic collapse in the southern Variscan realm. While juvenile tholeiitic basaltic magma was produced by the melting of spinel mantle lithosphere, all

  14. Group devaluation and group identification

    NARCIS (Netherlands)

    Leach, C.W.; Rodriguez Mosquera, P.M.; Vliek, M.L.W.; Hirt, E.

    2010-01-01

    In three studies, we showed that increased in-group identification after (perceived or actual) group devaluation is an assertion of a (preexisting) positive social identity that counters the negative social identity implied in societal devaluation. Two studies with real-world groups used order

  15. Lie groups and algebraic groups

    Indian Academy of Sciences (India)

    We give an exposition of certain topics in Lie groups and algebraic groups. This is not a complete ... of a polynomial equation is equivalent to the solva- bility of the equation ..... to a subgroup of the group of roots of unity in k (in particular, it is a ...

  16. Group Work

    Science.gov (United States)

    Wilson, Kristy J.; Brickman, Peggy; Brame, Cynthia J.

    2018-01-01

    Science, technology, engineering, and mathematics faculty are increasingly incorporating both formal and informal group work in their courses. Implementing group work can be improved by an understanding of the extensive body of educational research studies on this topic. This essay describes an online, evidence-based teaching guide published by…

  17. Reflection groups

    International Nuclear Information System (INIS)

    Eggermont, G.

    2006-01-01

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  18. Integrated multi-stratigraphic study of the Coll de Terrers late Permian-Early Triassic continental succession from the Catalan Pyrenees (NE Iberian Peninsula): A geologic reference record for equatorial Pangaea

    Science.gov (United States)

    Mujal, Eudald; Fortuny, Josep; Pérez-Cano, Jordi; Dinarès-Turell, Jaume; Ibáñez-Insa, Jordi; Oms, Oriol; Vila, Isabel; Bolet, Arnau; Anadón, Pere

    2017-12-01

    The most severe biotic crisis on Earth history occurred during the Permian-Triassic (PT) transition around 252 Ma. Whereas in the marine realm such extinction event is well-constrained, in terrestrial settings it is still poorly known, mainly due to the lack of suitable complete sections. This is utterly the case along the Western Tethys region, located at Pangaea's equator, where terrestrial successions are typically build-up of red beds often characterised by a significant erosive gap at the base of the Triassic strata. Henceforth, documenting potentially complete terrestrial successions along the PT transition becomes fundamental. Here, we document the exceptional Coll de Terrers area from the Catalan Pyrenees (NE Iberian Peninsula), for which a multidisciplinary research is conducted along the PT transition. The red-bed succession, located in a long E-W extended narrow rift system known as Pyrenean Basin, resulted from a continuous sedimentary deposition evolving from meandering (lower Upper Red Unit) to playa-lake/ephemeral lacustrine (upper Upper Red Unit) and again to meandering settings (Buntsandstein facies). Sedimentary continuity is suggested by preliminary cyclostratigraphic analysis that warrants further analysis. Our combined sedimentological, mineralogical and geochemical data infer a humid-semiarid-humid climatic trend across the studied succession. The uppermost Permian strata, deposited under an orbitally controlled monsoonal regime, yields a relatively diverse ichnoassemblage mainly composed of tetrapod footprints and arthropod trace fossils. Such fossils indicate appropriate life conditions and water presence in levels that also display desiccation structures. These levels alternate with barren intervals formed under dry conditions, being thus indicative of strong seasonality. All these features are correlated with those reported elsewhere in Gondwana and Laurasia, and suggest that the Permian-Triassic boundary might be recorded somewhere around

  19. 75 FR 24619 - Order Finding That the Permian Financial Basis Contract Traded on the IntercontinentalExchange...

    Science.gov (United States)

    2010-05-05

    ..., industrial gases, pharmaceutical, aluminum and brewing.'' WGCEF describes itself as ``a diverse group of... from Industrial Energy Consumers of America (``IECA''), Working Group of Commercial Energy Firms (``WGCEF''), Platts, ICE, Economists Incorporated (``EI''), Natural Gas Supply Association (``NGSA...

  20. Group theory

    CERN Document Server

    Scott, W R

    2010-01-01

    Here is a clear, well-organized coverage of the most standard theorems, including isomorphism theorems, transformations and subgroups, direct sums, abelian groups, and more. This undergraduate-level text features more than 500 exercises.

  1. Group Grammar

    Science.gov (United States)

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  2. Computer group

    International Nuclear Information System (INIS)

    Bauer, H.; Black, I.; Heusler, A.; Hoeptner, G.; Krafft, F.; Lang, R.; Moellenkamp, R.; Mueller, W.; Mueller, W.F.; Schati, C.; Schmidt, A.; Schwind, D.; Weber, G.

    1983-01-01

    The computer groups has been reorganized to take charge for the general purpose computers DEC10 and VAX and the computer network (Dataswitch, DECnet, IBM - connections to GSI and IPP, preparation for Datex-P). (orig.)

  3. Group learning

    DEFF Research Database (Denmark)

    Pimentel, Ricardo; Noguira, Eloy Eros da Silva; Elkjær, Bente

    The article presents a study that aims at the apprehension of the group learning in a top management team composed by teachers in a Brazilian Waldorf school whose management is collective. After deciding to extend the school, they had problems recruiting teachers who were already trained based...... on the Steiner´s ideas, which created practical problems for conducting management activities. The research seeks to understand how that group of teachers collectively manage the school, facing the lack of resources, a significant heterogeneity in the relationships, and the conflicts and contradictions......, and they are interrelated to the group learning as the construction, maintenance and reconstruction of the intelligibility of practices. From this perspective, it can be said that learning is a practice and not an exceptional phenomenon. Building, maintaining and rebuilding the intelligibility is the group learning...

  4. Group technology

    International Nuclear Information System (INIS)

    Rome, C.P.

    1976-01-01

    Group Technology has been conceptually applied to the manufacture of batch-lots of 554 machined electromechanical parts which now require 79 different types of metal-removal tools. The products have been grouped into 7 distinct families which require from 8 to 22 machines in each machine-cell. Throughput time can be significantly reduced and savings can be realized from tooling, direct-labor, and indirect-labor costs

  5. Permian basalts and trachytes from Esterel (SE France): a transitional tholeiitic suite emplaced during lithosphere thinning; Basaltes et trachytes permiens de l`Esterel (SE France): une serie tholeiitique transitionnelle epanchee pendant l`amincissement lithospherique

    Energy Technology Data Exchange (ETDEWEB)

    Lapierre, H.; Basile, Ch. [Grenoble-1 Univ., 38 - Grenoble (France). Laboratoire de Geodynamique des Chaines Alpines, CNRS UPRES-A5025; Dupuis, V. [Institut de Geodynamique, UMR Geosciences Azur, 06 - Valbonne (France)

    1999-11-01

    Geochemical (major, trace and rare earth elements) and isotopic ({sup 143}Nd/{sup 144}Nd) compositions of lavas emplaced in the Esterel Massif (eastern Provence, France) at the end of the Permian allow to estimate the evolution of the continental lithosphere between the end of the Hercynian orogenesis and the beginning of the Tethyan rifting. Basalts from Agay basin and trachyte from Batterie des Lions belong to a transitional tholeiitic suite, characterized by negative Nb and Ta anomalies (relative to N-MORB) and homogeneous {epsilon}Nd{sub (T=250Ma)} ratios, close to the Bulk Earth. This suggests that the basalts from Agay basin and trachyte from Batterie des Lions derived from the partial melting of a mantle contaminated by lower continental crust. Maure Vieille trachytes differ from the differentiated rocks of the transitional suite by higher heavy rare earth abundances and {epsilon}Nd{sub (T=250Ma)} of +4/+5. These high {xi}Nd ratios suggest that the Maure Vieille trachytes could derive from the partial melting of a more depleted source, likely an asthenospheric mantle. The isotopic compositions of the Permian lavas from Esterel suggest the thinning (and perhaps the disappearance) of the lithospheric mantle which is associated at the surface with a NNW-SSE extension. The progressive change recorded in Agay basin from a stretching regime to a strike-slip regime may be related to the end of the lithospheric thinning and of the Permian magmatism. (authors) 37 refs.

  6. Proliferation of MISS-related microbial mats following the end-Permian mass extinction in terrestrial ecosystems: Evidence from the Lower Triassic of the Yiyang area, Henan Province, North China

    Science.gov (United States)

    Tu, Chenyi; Chen, Zhong-Qiang; Retallack, Gregory J.; Huang, Yuangeng; Fang, Yuheng

    2016-03-01

    Microbially induced sedimentary structures (MISSs) are commonly present in siliciclastic shallow marine settings following the end-Permian mass extinction, but have been rarely reported in the post-extinction terrestrial ecosystems. Here, we present six types of well-preserved MISSs from the upper Sunjiagou Formation and lower Liujiagou Formation of Induan (Early Triassic) age in the Yiyang area, Henan Province, North China. These MISSs include: polygonal sand cracks, worm-like structures, wrinkle structures, sponge pore fabrics, gas domes, and leveled ripple marks. Microanalysis shows that these MISSs are characterized by thin clayey laminae and filamentous mica grains arranged parallel to bedding plane as well as oriented matrix supported quartz grains, which are indicative of biogenic origin. Facies analysis suggests that the MISS-hosting sediments were deposited in a fluvial sedimentary system during the Early Triassic, including lake delta, riverbeds/point bars, and flood plain paleoenvironments. Abundant MISSs from Yiyang indicate that microbes also proliferated in terrestrial ecosystems in the aftermath of the Permian-Triassic (P-Tr) biocrisis, like they behaved in marine ecosystems. Microbial blooms, together with dramatic loss of metazoans, may reflect environmental stress and degradation of terrestrial ecosystems or arid climate immediately after the severe Permian-Triassic ecologic crisis.

  7. Abelian groups

    CERN Document Server

    Fuchs, László

    2015-01-01

    Written by one of the subject’s foremost experts, this book focuses on the central developments and modern methods of the advanced theory of abelian groups, while remaining accessible, as an introduction and reference, to the non-specialist. It provides a coherent source for results scattered throughout the research literature with lots of new proofs. The presentation highlights major trends that have radically changed the modern character of the subject, in particular, the use of homological methods in the structure theory of various classes of abelian groups, and the use of advanced set-theoretical methods in the study of undecidability problems. The treatment of the latter trend includes Shelah’s seminal work on the undecidability in ZFC of Whitehead’s Problem; while the treatment of the former trend includes an extensive (but non-exhaustive) study of p-groups, torsion-free groups, mixed groups, and important classes of groups arising from ring theory. To prepare the reader to tackle these topics, th...

  8. Inheritance, Variscan tectonometamorphic evolution and Permian to Mesozoic rejuvenations in the metamorphic basement complexes of the Romanian Carpathians revealed by monazite microprobe geochronology

    Science.gov (United States)

    Săbău, Gavril; Negulescu, Elena

    2014-05-01

    Monazite U-Th-Pb chemical dating reaches an acceptable compromise between precision and accuracy on one side, and spatial resolution and textural constraints on the other side. Thus it has a powerful potential in testing the coherence of individual metamorphic basement units, and enabling correlations among them. Yet, sensitivity and specificity issues in monazite response to thermotectonic events, especially in the case of superposed effects, remain still unclear. Monazite dating at informative to detailed scale in the main metamorphic basement units of the Carpathians resulted in complex age spectra. In the main, the spectra are dominated by the most pervasive thermal and structural overprint, as checked against independent geochronological data. Post-peak age resetting is mostly present, but statistically subordinate. Resetting in case of superposed events is correlated with the degree of textural and paragenetic overprinting, inheritances being always indicated by more or less well-defined age clusters. The lack of relict ages correlating with prograde structural and porphyroblast zonation patterns is indicative for juvenile formations. Age data distribution in the Carpathians allowed distinction of pre-Variscan events, syn-metamorphic Variscan tectonic stacking of juvenile and reworked basement, post-Variscan differential tectonic uplift, as well as prograde metamorphic units ranging down to Upper Cretaceous ages. In the South Carpathians, the Alpine Danubian domain consists of several Variscan and Alpine thrust sheets containing a metamorphic complex dominated by Upper Proterozoic to Lower Cambrian metamorphic and magmatic ages (Lainici-Păiuş), and several complexes with metamorphic overprints ranging from Carboniferous to Lower Permian. Any correlation among these units, as well as geotectonic models placing a Lower Paleozoic oceanic domain between pre-existing Lainici-Păiuş and Drăgşan terranes are precluded by the age data. Other basement of the

  9. Group dynamics.

    Science.gov (United States)

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  10. Field geology, geochronology and geochemistry of mafic-ultramafic rocks from Alxa, China: Implications for Late Permian accretionary tectonics in the southern Altaids

    Science.gov (United States)

    Feng, Jianyun; Xiao, Wenjiao; Windley, Brian; Han, Chunming; Wan, Bo; Zhang, Ji'en; Ao, Songjian; Zhang, Zhiyong; Lin, Lina

    2013-12-01

    south-dipping subduction, most probably with a slab window caused by ridge subduction, of the Paleo-Asian Ocean plate beneath the Alxa block in the Late Carboniferous to Late Permian before the Ocean completely closed. This sheds light on the controversial tectonic history of the southern Altaids and supports the concept that the termination of orogenesis was in the end-Permian to Triassic.

  11. Carboniferous-Permian tectonic transition envisaged in two magmatic episodes at the Kuruer Cu-Au deposit, Western Tianshan (NW China)

    Science.gov (United States)

    Yu, Jie; Li, Nuo; Qi, Nan; Guo, Jian-Ping; Chen, Yan-Jing

    2018-03-01

    The Western Tianshan in NW China is one of the most important gold provinces in the Central Asian Orogenic Belt (CAOB). The recently discovered Kuruer Cu-Au deposit has been interpreted to represent a transition from high-sulfidation epithermal to porphyry mineralization system. In this study, we present new LA-ICP-MS zircon U-Pb ages for the many magmatic rock types at Kuruer, including the Dahalajunshan Formation andesitic tuff (333.2 ± 1.6 Ma), diorite porphyry (269.7 ± 2.0 Ma), slightly-altered (264.4 ± 2.6 Ma) and intensively-altered (270.5 ± 2.5