Facies-succession and architecture of the third-order sequences and their stratigraphic framework of the Devonian in Yunnan-Guizhou-Guangxi area, South China

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Mei Mingxiang

2013-01-01

Full Text Available The Caledonian orogeny at the end of the Silurian resulted in great changes in the palaeogeography in the Yunnan-Guizhou-Guangxi area of South China; the continental area of the Early Paleozoic evolved into the extensive Dian-Qian-Gui Sea in the Late Paleozoic. Early in the Devonian, as a result of a major transgression, seawater encroached gradually from the south to the north and clastic facies were deposited. Carbonate deposition was then established in the Yunnan-Guizhou-Guangxi area, with a palaeogeography marked by attached platforms, isolated platforms and narrow basins. As a result of the Ziyun movement towards the end of the Devonian, the Upper Devonian strata are regressive and thin out from the open-sea to the land areas. A study of the nature and distribution of sedimentary facies in space and time recognises 13 third-order sequences in the Devonian strata in Yunnan-Guizhou-Guangxi area, and these form two second-order sequences. The strata of the Lower Devonian comprise 5 third-order sequences (SQ1 to SQ5, which are dominated by transgressive clastics. 4 third-order sequences (SQ6 to SQ9 in the Middle Devonian are characterized by alternations of transgressive clastics and highstand carbonates. In the Upper Devonian, carbonates constitute 4 third-order sequences (SQ10 to SQ13, which are generally marked by the transgressive limestones and highstand dolomites. On the basis of earlier biostratigraphic studies, sea-level changes represented by the third-order sequences with their different facies successions are explored, and the sequence stratigraphic framework is established. Therefore, the Devonian strata in the study area provide an example for further understanding of depositional trends within the sequence-stratigraphic framework.

The Devonian Marcellus Shale and Millboro Shale

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Soeder, Daniel J.; Enomoto, Catherine B.; Chermak, John A.

2014-01-01

The recent development of unconventional oil and natural gas resources in the United States builds upon many decades of research, which included resource assessment and the development of well completion and extraction technology. The Eastern Gas Shales Project, funded by the U.S. Department of Energy in the 1980s, investigated the gas potential of organic-rich, Devonian black shales in the Appalachian, Michigan, and Illinois basins. One of these eastern shales is the Middle Devonian Marcellus Shale, which has been extensively developed for natural gas and natural gas liquids since 2007. The Marcellus is one of the basal units in a thick Devonian shale sedimentary sequence in the Appalachian basin. The Marcellus rests on the Onondaga Limestone throughout most of the basin, or on the time-equivalent Needmore Shale in the southeastern parts of the basin. Another basal unit, the Huntersville Chert, underlies the Marcellus in the southern part of the basin. The Devonian section is compressed to the south, and the Marcellus Shale, along with several overlying units, grades into the age-equivalent Millboro Shale in Virginia. The Marcellus-Millboro interval is far from a uniform slab of black rock. This field trip will examine a number of natural and engineered exposures in the vicinity of the West Virginia–Virginia state line, where participants will have the opportunity to view a variety of sedimentary facies within the shale itself, sedimentary structures, tectonic structures, fossils, overlying and underlying formations, volcaniclastic ash beds, and to view a basaltic intrusion.

Biogeography of late Silurian and devonian rugose corals

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Oliver, W.A.

1977-01-01

Three marine benthic faunal realms can be recognized in the Early and Middle Devonian. The Eastern Americas Realm consisted of most of the eastern half of North America and South America north of the Amazon. This realm extended in a southwest direction from the Devonian equator to approximately 35??S and was an isolated epicontinental sea during much of its history. The Eastern Americas Realm was bounded on the west by the Transcontinental Arch, on the north by the Canadian Shield and on the east and southeast by a peninsular extension of the Old Red Continent. These barriers were emergent during much, but not all, of Devonian time. Seaways beyond these barriers belonged to the Old World Realm. The Malvinokaffric Realm that was farther south was apparently temperate to arctic in climate and latitudinal position and contained few corals. Rugose corals in the Eastern Americas Realm show increasing generic-level endemism from the Late Silurian through the Early Devonian; during the late Early Devonian, 92% of the rugosan genera are not known anywhere else in the world. Endemism decreased through the Middle Devonian to zero in the early Late Devonian. The Early Devonian increase in endemism paralleled, and was probably related to, the development of the Old Red Continent as a barrier between America and Africa-Europe. The waning of endemism in the Middle Devonian reflects the breaching of the land barriers. This permitted some migration in and out of the realm in early Middle Devonian time but greatest movements were in late Middle Devonian time. Principal migration directions were from western or Arctic North America into the Michigan-Hudson Bay area and from the southern Appalachian area into Africa. ?? 1977.

Carbon isotopic record from Upper Devonian carbonates at Dongcun in Guilin, southern China, supporting the world-wide pattern of carbon isotope excursions during Frasnian-Famennian transition

Institute of Scientific and Technical Information of China (English)

无

2003-01-01

Two positive δ13C excursions are presented in records from the Frasnian-Famennian (F-F) marine carbonate sediments in Europe, America, Africa, and Australia, having been considered as a worldwide pattern, and attributed to enhanced organic carbon burial during the F-F biological mass extinction. However, this worldwide pattern has not been revealed from the well-deposited Late Devonian sequences in southern China. In this paper, a detailed investigation has been made on the Late Devonian section at Dongcun, Guilin, southern China to constrain perturbations in δ13C of carbonates in the F-F deposited sequence. The result from this section also indicates two positive δ13C excursions during the F-F transition. The first excursion with an amplitude of 1.5‰ occurred at the bottom of linguiformis Zone, later than the early excursion existing in the Late rhenana Zone of the Late Devonian profiles in other continents, especially, in central Europe. This difference has been expected to be a result as conodont Palmatolepis linguiformis occurred earlier in southern China than other sites. The second excursion with an amplitude of 2.1‰ is located at the F-F boundary, same as the records from other continents. This result strongly supports the view that two carbon isotope positive excursions during the F-F transition are common in carbonate sediments, resulting from worldwide increases of organic carbon burial intensity.

Vascular plants from the Devonian to Lower Cretaceous in southern Africa

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J. M. Anderson

1983-11-01

Full Text Available The succession of pre-angiospermous megafloras in southern Africa from the Devonian to Lower Cretaceous is outlined. Interrelationships between continental drift, global climatic trends, and floral and faunal evolution are emphasized. Data are given on numbers of assemblages sampled; on species diversity; and on relative abundance of each genus per productive ‘formation’. A total of 79 genera and about 250 species are recognized in the 150 assemblages from the 11 horizons considered. Floras are unknown from the Carboniferous and are as yet undescribed from the Jurassic. Aside from these gaps, a good idea of the floral development is obtained. Diversity lows of around 5 to 10 species per ‘formation’ are witnessed in the Devonian, whereas a peak of 112 species is encountered in the Upper Triassic Molteno Formation. Diversity remains around 20 to 30 species for all other ‘formations’.

New U-Pb zircon ages and the duration and division of Devonian time

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Tucker, R.D.; Bradley, D.C.; Ver Straeten, C.A.; Harris, A.G.; Ebert, J.R.; McCutcheon, S.R.

1998-01-01

Newly determined U-Pb zircon ages of volcanic ashes closely tied to biostratigraphic zones are used to revise the Devonian time-scale. They are: 1) 417.6 ?? 1.0 Ma for an ash within the conodont zone of Icriodus woschmidti/I. w. hesperius Lochkovian); 2) 408.3 ?? 1.9 Ma for an ash of early Emsian age correlated with the conodont zones of Po. dehiscens--Lower Po. inversus; 3) 391.4 ?? 1.8 Ma for an ash within the Po. c. costatus Zone and probably within the upper half of the zone (Eifelian); and 4) 381.1 ?? 1.3 Ma for an ash within the range of the Frasnian conodont Palmatolepis punctata (Pa. punctata Zone to Upper Pa. hassi Zone). U-Pb zircon ages for two rhyolites bracketing a palyniferous bed of the pusillites-lepidophyta spore zone, are dated at 363.8 ?? 2.2 Ma and 363 ?? 2.2 Ma and 363.4 ?? 1.8 Ma, respectively, suggesting an age of ~363 Ma for a level within the late Famennian Pa. g. expansa Zone. These data, together with other published zircon ages, suggest that the base and top of the Devonian lie close to 418 Ma and 362 Ma, respectively, thus lengthening the period of ~20% over current estimates. We suggest that the duration of the Middle Devonian (Eifelian and Givitian) is rather brief, perhaps no longer than 11.5 Myr (394 Ma-382.5 Ma), and that the Emsian and Famennian are the longest stages in the period with estimated durations of ~15.5 Myr and 14.5 Myr, respectively.

Terrestrial P and Reactive N and Marine Productivity in the Late Devonian Appalachian Basin

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Tuite, M. L.; Macko, S. A.

2009-12-01

A causal link between the Late Devonian emergence of forest ecosystems and episodic black shale deposition has been proposed by several authors. Most attribute increases in epicontinental basin productivity to elevated rates of terrestrial phosphorus weathering facilitated by the co-evolution of root systems and soils. Two reasons to suspect that an increase in the P weathering flux was not the primary cause of organic-rich shale deposition are as follows. First, most Late Devonian black shales were deposited during sea level transgressions, periods when riverine fluxes of sediment and mineral nutrients such as P to marine basins were diminished. Second, Late Devonian forests were restricted to warm, moist lowlands where P was sequestered in soils as inorganic, occluded forms. However, the export flux of reactive N from these forests to adjacent epeiric seas by riverine and atmospheric deposition was enhanced by the warm, wet climate and expanding areal extent of forests. Abundant terrestrial reactive N primed the marine eutrophication pump by extending the residence time of P in the photic zone, permitting extensive growth of primary biomass. The consequent flux of organic matter to the sea floor created anoxic bottom waters that, in turn, allowed for the remobilization of P into the water column. Based on abundance and isotopic analyses of organic and inorganic C, N, P, and S from terrestrial and marine environments within and adjacent to the Late Devonian Appalachian Basin, this latter scenario is supported.

Radiometric evidence of Middle Devonian inversion of the Hill End Trough, northeast Lachlan Fold Belt

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Pakham, G.H.

1999-01-01

The publication of a new geological time-scale by the Australian Geological Survey Organisation and radiometric dates from the Hill End goldfield have prompted the re-examination of the timing of deformation of the Hill End Trough to determine whether it occurred in Middle Devonian or Early Carboniferous time. Palaeontological evidence from the western trough margin and the Capertee High dates the end of deposition in the trough as late Emsian or early Eifelian (385-382 Ma). After a mid-Devonian hiatus of at least 15 million years, paralic sedimentation commenced on the Molong and Capertee Highs in late Frasnian or early Famennian time (367-363 Ma). No Upper Devonian sedimentary formations occur in the Hill End Trough. Structural relationships indicate that the oldest mineral veins at Hill End preceded cleavage formation in the deformed trough sedimentary rocks. Early vein muscovites have Middle Devonian 40 Ar/ 39 Ar dates of 380-370 Ma. Regional metamorphic biotites from Hill End have well constrained 40 Ar/ 39 Ar closing ages of 360-358 Ma (mid-Famennian). The metamorphic (thermal) maximum which outlasted penetrative deformation. is estimated here by modelling to have been about 370 Ma (latest Givetian). This clearly places the earlier main deformation in the Middle Devonian. Deformation probably began by terminating trough deposition in latest Emsian to early Eifelian time and ended in early Givetian time at about 375 Ma ago. Published pressure and temperature data from the Hill End goldfield suggest that deformation thickened the 6 km sediment column to around 11 km. The thermal model suggests there was post-deformation erosion of about 4km and little if any further erosion occurred during Late Devonian to Early Carboniferous time. The shortening accompanying the inversion of the northern Hill End Trough may have been taken up in the region to the south, both east and west of the Copperhannia Thrust, and east of the southern termination of the Capertee High

A rich ichnofossil assemblage from the Frasnian (Upper Devonian) deposits at Andoma Hill, Onega Lake, Russia

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek; Meškis, S.; Ivanov, A.; Lukševičs, E.; Zupinš, I.; Stinkulis, G.

2013-01-01

Roč. 88, č. 2 (2013), s. 389-400 ISSN 1214-1119 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:67985831 Keywords : ichnology * East European Platform * Main Devonian field * Old Red Sandstone facies Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.495, year: 2013

Towards a High-resolution Time Scale for the Early Devonian

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Dekkers, M. J.; da Silva, A. C.

2017-12-01

High-resolution time scales are crucial to understand Earth's history in detail. The construction of a robust geological time scale, however, inevitably becomes increasingly harder further back in time. Uncertainties associated with anchor radiometric ages increase in size, not speaking of the mere presence of suitable datable strata. However, durations of stages can be tightly constrained by making use of cyclic expressions in sediments, an approach that revolutionized the Cenozoic time scale. When precisely determined durations are stitched together, ultimately, a very precise time scale is the result. For the Mesozoic and Paleozoic an astronomical solution as a tuning target is not available but the dominant periods of eccentricity, obliquity and precession are reasonably well constrained for the entire Phanerozoic which enables their detection by means of spectral analysis. Eccentricity is time-invariant and is used as the prime building block. Here we focus on the Early Devonian, on its lowermost three stages: the Lochkovian, Pragian and Emsian. The uncertainties on the Devonian stage boundaries are currently in the order of several millions of years. The preservation of climatic cycles in diagenetically or even anchimetamorphically affected successions, however, is essential. The fit of spectral peak ratios with those calculated for orbital cycles, is classically used as a strong argument for a preserved climatic signal. Here we use primarily the low field magnetic susceptibility (MS) as proxy parameter, supported by gamma-ray spectrometry to test for consistency. Continuous Wavelet Transform, Evolutive Harmonic Analysis, Multitaper Method, and Average Spectral Misfit are used to reach an optimal astronomical interpretation. We report on classic Early Devonian sections from the Czech Republic: the Pozar-CS (Lochkovian and Pragian), Pod Barrandovem (Pragian and Lower Emsian), and Zlichov (Middle-Upper Emsian). Also a Middle-Upper Emsian section from the US

Stratigraphic architecture of Devonian lacustrine basins of northern Scotland

DEFF Research Database (Denmark)

Kristiansen, Thorben; Moreau, Julien; Andrews, Steven D.

of this important surface has received relatively little attention. We have utilized vintage onshore seismic to gain a better understanding of the pre-Devonian basement physiography. Onshore exposures of the top Moine, base Devonian unconformity surface is exposed have been visited to ground truth our subsurface...... interpretations. The studied deposits have been deeply buried then exhumed so that they are exposed widely onshore. Post Caledonian tectonism has faulted and folded the Devonian succession making it challenging to reconstruct the stratigraphy and the basin architecture from geological data only. The Devonian...

Devonian climate and reef evolution: Insights from oxygen isotopes in apatite

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Joachimski, M. M.; Breisig, S.; Buggisch, W.; Talent, J. A.; Mawson, R.; Gereke, M.; Morrow, J. R.; Day, J.; Weddige, K.

2009-07-01

Conodonts, microfossils composed of carbonate-fluor apatite, are abundant in Palaeozoic-Triassic sediments and have a high potential to preserve primary oxygen isotope signals. In order to reconstruct the palaeotemperature history of the Devonian, the oxygen isotope composition of apatite phosphate was measured on 639 conodont samples from sequences in Europe, North America and Australia. The Early Devonian (Lochkovian; 416-411 Myr) was characterized by warm tropical temperatures of around 30 °C. A cooling trend started in the Pragian (410 Myr) with intermediate temperatures around 23 to 25 °C reconstructed for the Middle Devonian (397-385 Myr). During the Frasnian (383-375 Myr), temperatures increased again with temperatures to 30 °C calculated for the Frasnian-Famennian transition (375 Myr). During the Famennian (375-359 Myr), surface water temperatures slightly decreased. Reconstructed Devonian palaeotemperatures do not support earlier views suggesting the Middle Devonian was a supergreenhouse interval, an interpretation based partly on the development of extensive tropical coral-stromatoporoid communities during the Middle Devonian. Instead, the Devonian palaeotemperature record suggests that Middle Devonian coral-stromatoporoid reefs flourished during cooler time intervals whereas microbial reefs dominated during the warm to very warm Early and Late Devonian.

Cyclostratigraphic calibration of the Famennian stage (Late Devonian, Illinois Basin, USA)

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Pas, Damien; Hinnov, Linda; Day, James E. (Jed); Kodama, Kenneth; Sinnesael, Matthias; Liu, Wei

2018-04-01

The Late Devonian biosphere was affected by two of the most severe biodiversity crises in Earth's history, the Kellwasser and Hangenberg events near the Frasnian-Famennian (F-F) and the Devonian-Carboniferous (D-C) boundaries, respectively. Current hypotheses for the causes of the Late Devonian extinctions are focused on climate changes and associated ocean anoxia. Testing these hypotheses has been impeded by a lack of sufficient temporal resolution in paleobiological, tectonic and climate proxy records. While there have been recent advances in astronomical calibration that have improved the accuracy of the Frasnian time scale and part of the Famennian, the time duration of the entire Famennian Stage remains poorly constrained. During the Late Devonian, a complete Late Frasnian-Early Carboniferous succession of deep-shelf deposits accumulated in the epieric sea in Illinois Basin of the central North-American mid-continent. A record of this sequence is captured in three overlapping cores (H-30, Sullivan and H-32). The H-30 core section spans the F-F boundary; the Sullivan section spans almost all of the Famennian and the H-32 section sampled spans the interval of the Upper Famennian and the D-C boundary. To have the best chance of capturing Milankovitch cycles, 2000 rock samples were collected at minimum 5-cm-interval across the entire sequence. Magnetic susceptibility (MS) was measured on each sample and the preservation of climatic information into the MS signal was verified through geochemical analyses and low-temperature magnetic susceptibility acquisition. To estimate the duration of the Famennian Stage, we applied multiple spectral techniques and tuned the MS signal using the highly stable 405 kyr cycle for Sullivan and the obliquity cycle for the H-30 and H-32 cores. Based on the correlation between the cores we constructed a Famennian floating astronomical time scale, which indicates a duration of 13.5 ± 0.5 myr. An uncertainty of 0.5 myr was estimated for

Lower and Middle Devonian Malvinokaffric ostracods from the Precordillera Basin of San Juan, Argentina

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Salas, María J.; Rustán, Juan J.; Sterren, Andrea F.

2013-08-01

Ostracod from the upper Lower to Middle Devonian rocks of the Argentine Precordillera Basin (Talacasto and Punta Negra formations) are studied. One new genus Pircawayra nov. gen., and five species (including three new: Pircawayra gigantea nov. gen. and sp., Lapazites trinodis nov. sp. and Keslingiella? teresae nov. sp.) are defined. The recorded ostracod fauna closely resembles that coeval from Bolivia and South Africa, exhibiting a remarkable endemism, not only at the genus level, but also at the species level. In addition to its low-diversity, the Malvinokaffric ostracod association is also characterized by having large, thick, coarsely ornamented and swollen valves. The similar ostracod composition from the Andean and South African basins suggests faunal exchange between these two areas. Based on the ostracod faunas, the Malvinokaffric Realm is clearly recognizable at least up to the Middle Devonian.

Geochemical and palaeontological evidence for the definition of the Silurian/Devonian boundary in the Changwantang Section, Guangxi Province, China

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Wen-jin Zhao

2015-02-01

Full Text Available Southern Guangxi Province is one of the important areas for the study of the Silurian/Devonian boundary (SDB in South China. Despite attempts to define the exact level of the SDB in the Yulin (Guangxi Province area using biostratigraphy, no consensus has been reached as the indicator fossils (e.g. graptolite Monograptus uniformis uniformis, conodont Icriodus woschmidti woschmidti and trilobite Warburgella rugulosa rugosa are not coexistent in South China. Since Mann et al. (2001: Dynamics of the Silurian/Devonian boundary sequence: sedimentary cycles vs. organic matter variation. Terra Nostra, 2001, 44–48 reported the first isotope curve based on organic carbon for the SDB at Klonk in the Czech Republic (GSSP, some comparable variation curves of δ13Corg across the SDB have been obtained at several locations including sections in Turkey and China. This distinct variation curve of the isotopic composition of organic carbon across the SDB provides a chemostratigraphic reference for a worldwide correlation of the SDB. In this study, organic geochemistry together with graptolite biostratigraphy is applied as a tool for identifying the SDB at the Changwantang Section in Yulin (Guangxi Province. The results suggest that the variations in some indexes of organic geochemistry can be correlated to the representative curve of the SDB in the Klonk and Esenyali sections. The exact level of the SDB in the Changwantang Section is positioned within the upper part of the Fangcheng Formation, which is consistent with the available palaeontological data from graptolites (e.g. Colonograptus colonus, Plectograptus sp., Monograptus uniformis, M. cf. M. praehercynicus and M. aequabilis.

Geology of redbed Cu-U occurrences in the Upper Devonian Catskill Fm., Pennsylvania

International Nuclear Information System (INIS)

Smith, A.T.

1983-01-01

A regional and detailed geologic, petrographic and geochemical study of 40 redbed Cu-U occurrences and the host Upper Devonian Catskill Fm. in Pennsylvania shows that depositional environment and diagenetic processes were the most important controls on the formation of the occurrences. The Catskill Fm. in Pa. has been divided into 4 magnafacies (Mf). In ascending order, Mf-A contains interbedded marine and non-marine shale and fine sandstones; Mf-B contains mainly thick red shales and thin sandstones interpreted to be low-energy fluvial deposits on an inactive coastal plain interrupted by occasional thin transgressive marine sandstones. Mf-C is composed of thick sandstones deposited by braided rivers; and Mf-D is composed of thick fining-up cycles deposited by meandering rivers. The Cu-U occurrences are located in areas of thick Mf-B; they occur in Mf-A, -B and -D. Cu-sulfides formed during diagenesis with chlorite in pockets of plant trash within or below a marine or fluvial sandstones, which contain a greater percentage of ductile grains than similar sandstones are inferred to have been more permeable than non-mineralized sandstones. The Cu-sulfides formed after early hematite, clay coatings and calcite cement. Based on isotopic, textural and compositional evidence, the calcite is considered to have formed near the surface at temperatures of less than 100 0 C from oxidizing waters reduced by plant material. The Cu and U in a typical occurrence could easily have been derived by leaching of 1-3% of the total Cu and U from a volume of sediment equivalent to a cube of 40 m or less on a side. Cu appears to have been mobilized during compaction and was derived from the fine fraction of the sediments by Cl-bearing solutions introduced during marine transgressions

Geology of the Devonian black shales of the Appalachian Basin

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Roen, J.B.

1984-01-01

Black shales of Devonian age in the Appalachian Basin are a unique rock sequence. The high content of organic matter, which imparts the characteristic lithology, has for years attracted considerable interest in the shales as a possible source of energy. The recent energy shortage prompted the U.S. Department of Energy through the Eastern Gas Shales Project of the Morgantown Energy Technology Center to underwrite a research program to determine the geologic, geochemical, and structural characteristics of the Devonian black shales in order to enhance the recovery of gas from the shales. Geologic studies by Federal and State agencies and academic institutions produced a regional stratigraphic network that correlates the 15 ft black shale sequence in Tennessee with 3000 ft of interbedded black and gray shales in central New York. These studies correlate the classic Devonian black shale sequence in New York with the Ohio Shale of Ohio and Kentucky and the Chattanooga Shale of Tennessee and southwestern Virginia. Biostratigraphic and lithostratigraphic markers in conjunction with gamma-ray logs facilitated long-range correlations within the Appalachian Basin. Basinwide correlations, including the subsurface rocks, provided a basis for determining the areal distribution and thickness of the important black shale units. The organic carbon content of the dark shales generally increases from east to west across the basin and is sufficient to qualify as a hydrocarbon source rock. Significant structural features that involve the black shale and their hydrocarbon potential are the Rome trough, Kentucky River and Irvine-Paint Creek fault zone, and regional decollements and ramp zones. ?? 1984.

Stratigraphy, palynology and organic geochemistry of the Devonian-Mississippian metasedimentary Albergaria-a-Velha Unit (Porto-Tomar shear zone, W Portugal)

Czech Academy of Sciences Publication Activity Database

Machado, G.; Franců, E.; Vavrdová, Milada; Flores, D.; Fonseca, P. E.; Rocha, F.; Gama Pereira, L. C.; Gomes, A.; Fonseca, M.; Chaminé, H. I.

2011-01-01

Roč. 55, č. 2 (2011), s. 139-164 ISSN 1641-7291. [International Palynological Conference of the International Commission of the Paleozoic Microflora ( CIMP ). Warsaw-Kielce, 13.09.2010-19.09.2010] Institutional research plan: CEZ:AV0Z30130516 Keywords : Mississippian * Late Devonian * Ossa-Morena Zone * Porto-Tomar shear zone * palynology * organic geochemistry * turbidite systems * provenance * phytoplankton Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.844, year: 2011 http://gq.pgi.gov.pl/gq/article/viewFile/7606/pdf_4

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2005-04-26

Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2005-01-28

Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2005-07-29

Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. There is a direct correlation between measured total organic carbon content and the adsorptive capacity of the shale; CO{sub 2} adsorption capacity increases with increasing organic carbon content. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

Stratigraphy and facies development of the marine Late Devonian near the Boulongour Reservoir, northwest Xinjiang, China

Science.gov (United States)

Suttner, Thomas J.; Kido, Erika; Chen, Xiuqin; Mawson, Ruth; Waters, Johnny A.; Frýda, Jiří; Mathieson, David; Molloy, Peter D.; Pickett, John; Webster, Gary D.; Frýdová, Barbora

2014-02-01

Late Devonian to Early Carboniferous stratigraphic units within the 'Zhulumute' Formation, Hongguleleng Formation (stratotype), 'Hebukehe' Formation and the Heishantou Formation near the Boulongour Reservoir in northwestern Xinjiang are fossil-rich. The Hongguleleng and 'Hebukehe' formations are biostratigraphically well constrained by microfossils from the latest Frasnian linguiformis to mid-Famennian trachytera conodont biozones. The Hongguleleng Formation (96.8 m) is characterized by bioclastic argillaceous limestones and marls (the dominant facies) intercalated with green spiculitic calcareous shales. It yields abundant and highly diverse faunas of bryozoans, brachiopods and crinoids with subordinate solitary rugose corals, ostracods, trilobites, conodonts and other fish teeth. The succeeding 'Hebukehe' Formation (95.7 m) consists of siltstones, mudstones, arenites and intervals of bioclastic limestone (e.g. 'Blastoid Hill') and cherts with radiolarians. A diverse ichnofauna, phacopid trilobites, echinoderms (crinoids and blastoids) together with brachiopods, ostracods, bryozoans and rare cephalopods have been collected from this interval. Analysis of geochemical data, microfacies and especially the distribution of marine organisms, which are not described in detail here, but used for facies analysis, indicate a deepening of the depositional environment at the Boulongour Reservoir section. Results presented here concern mainly the sedimentological and stratigraphical context of the investigated section. Additionally, one Late Devonian palaeo-oceanic and biotic event, the Upper Kellwasser Event is recognized near the section base.

Lower Devonian lithofacies and palaeoenvironments in the southwestern margin of the East European Platform (Ukraine, Moldova and Romania

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Natalia Radkovets

2016-11-01

Full Text Available Lower Devonian palaeoshelf deposits extend along the western margin of the East European Platform from the Baltic Sea to the Black Sea. These deposits have been studied on the territory of Ukraine (Volyn-Podillyan Plate, Dobrogean Foredeep and correlated with coeval deposits in Moldova and Romania (Moldovian Platform. The investigation of the Lower Devonian deposits, their thickness, petrographic and lithological characteristics allowed reconstruction of two types of lithofacies and distinguishing two different depositional environments. The first lithofacies belonging to the Lochkovian stage, consists of clayey-carbonate rocks and represents a continuation of the Upper Silurian marine strata. The other lithofacies encompassing the Pragian–Emsian comprises terrigenous reddish-brown rocks, which are roughly equivalent to the Old Red Sandstone, completes the Lower Devonian section. Establishing the occurrence and thickness distribution of the terrigenous lithofacies across the study area is important, because it forms potential reservoir rocks for both conventional and unconventional (tight gas hydrocarbons. Gas accumulation in these reservoir rocks has been discovered at the Lokachi field.

GRI's Devonian Shales Research Program

International Nuclear Information System (INIS)

Guidry, F.K.

1991-01-01

This paper presents a summary of the key observations and conclusions from the Gas Research Institute's (GRI's) Comprehensive Study Well (CSW) research program conducted in the Devonian Shales of the Appalachian Basin. Initiated in 1987, the CSW program was a series of highly instrumented study wells drilled in cooperation with industry partners. Seven wells were drilled as part of the program. Extensive data sets were collected and special experiments were run on the CSW's in addition to the operator's normal operations, with the objectives of identifying geologic production controls, refining formation evaluation tools, and improving reservoir description and stimulation practices in the Devonian Shales. This paper highlights the key results from the research conducted in the CSW program in the areas of geologic production controls, formation evaluation, stimulation and reservoir engineering, and field operations. The development of geologic, log analysis, and reservoir models for the Shales from the data gathered and analysis, and reservoir models for the Shales from the data gathered and analyzed during the research is discussed. In addition, on the basis of what was learned in the CSW program, GRI's plans for new research in the Devonian Shales are described

Zircon dating of Devonian-Carboniferous rocks from the Bombala area, New South Wales

International Nuclear Information System (INIS)

Sircombe, K.N.; McQueen, K.G.

2000-01-01

Zircons from two igneous and two sedimentary units in the Bombala area of southeastern New South Wales have been examined by the sensitive high resolution ion microprobe (SHRIMP) to establish a time frame in which to interpret these rocks. Previous studies have correlated these rocks with Late Devonian units of the south coast, solely upon the basis of stratigraphy and lithology as palaeontological evidence was absent. The two igneous units are the Hospital Porphyry and Paradise Porphyry occurring beneath the sedimentary units. Both give a Frasnian age that can be correlated with the Boyd Volcanic Complex. The sedimentary samples are from the basal and upper sections of the Rosemeath Formation, a fluvial 'redbed' consisting of conglomerate, coarse sandstone, and associated red siltstone and mudstone. Detrital zircons from the basal conglomeratic section at Kilbrechin indicate a dominant provenance from local Silurian granites and volcanics and a maximum depositional age that can be correlated with the Frasnian-Famennian Merrimbula Group. However, detrital zircons from the upper coarse sandstone section of the Rosemeath Formation at Endeavour Lookout challenge the positive correlation trend with a lack of Silurian-age grains and a presence of grains ranging from Late Devonian to Early Carboniferous in age. These results imply either that the south coast correlation is not valid for the upper sequences, or that the Merrimbula Group sequences also extend upward into the Carboniferous. The general coarseness of the Rosemeath Formation also suggests a relatively local provenance. No Early Carboniferous source is known in the immediate vicinity suggesting that Early Carboniferous igneous activity in this region of the Lachlan Orogen may have been more extensive than is currently realised. Copyright (1999) Geological Society of Australia

Graphic correlation of the Frasnian Upper Devonian Composite

Energy Technology Data Exchange (ETDEWEB)

Klapper, G. (Univ. of Iowa, Iowa City, IA (United States). Dept. of Geology); Kirchgasser, W.T. (Potsdam Coll., NY (United States). Geology Dept.); Baesemann, J.F. (Amoco Production Co., Houston, TX (United States))

1993-03-01

Although statistical solution to the line of correlation (LOC) was advocated by Shaw (1964) when the technique of graphic correlation was introduced, most practioners, including Shaw himself shortly after publication of Time in Stratigraphy, agree that statistical methods for locating the LOC are inappropriate. As a consequence, calculation of the standard error of estimate and other statistical measures of error in order to quantify the resolution of graphic correlation is also inappropriate. Methods for locating the LOC are diverse involving geologic as well as biostratigraphic knowledge, and include positioning it with respect to magnetic reversals, volcanic ash beds, oxygen isotope data, and splitting bases and tops of species so as to cause minimum disruption in known ranges. The LOC for each section with the Composite Standard is a testable hypothesis of stratigraphic correlation. The Frasnian Composite consists of 27 sections in the Montagne Noire (southern France), Alberta Rockies, Hay River - Trout River areas of the Northwest Territories, Canada, the Midcontinent and New York sequences in the US, the Canning Basin, Western Australia, and the Central Devonian Field and Timan-Pechora Basin of the Russian Platform. Through graphic correlation, the Frasnian Stage is divided into 34 composite standard units, using ranges of conodonts and to a lesser extent goniatites. The resulting subdivision is considerably more precise than that achieved by the conventional thirteen-fold zonation based on the Montagne Noire conodont sequence, many zones of which have been replicated in the cited areas outside the Montagne Noire. The Frasnian Composite successfully provides a precise intrazonal method of correlation that uses the ranges of all species from the studies sections in a single biostratigraphic framework, rather than emphasizing a few zonal indices.

Placoderms (Armored Fish): Dominant Vertebrates of the Devonian Period

Science.gov (United States)

Young, Gavin C.

2010-05-01

Placoderms, the most diverse group of Devonian fishes, were globally distributed in all habitable freshwater and marine environments, like teleost fishes in the modern fauna. Their known evolutionary history (Early Silurian-Late Devonian) spanned at least 70 million years. Known diversity (335 genera) will increase when diverse assemblages from new areas are described. Placoderms first occur in the Early Silurian of China, but their diversity remained low until their main evolutionary radiation in the Early Devonian, after which they became the dominant vertebrates of Devonian seas. Most current placoderm data are derived from the second half of the group's evolutionary history, and recent claims that they form a paraphyletic group are based on highly derived Late Devonian forms; 16 shared derived characters are proposed here to support placoderm monophyly. Interrelationships of seven placoderm orders are unresolved because Silurian forms from China are still poorly known. The relationship of placoderms to the two major extant groups of jawed fishes—osteichthyans (bony fishes) and chondrichthyans (cartilaginous sharks, rays, and chimaeras)—remains uncertain, but the detailed preservation of placoderm internal braincase structures provides insights into the ancestral gnathostome (jawed vertebrate) condition. Placoderms provide the most complex morphological and biogeographic data set for the Middle Paleozoic; marked discrepancies in stratigraphic occurrence between different continental regions indicate strongly endemic faunas that were probably constrained by marine barriers until changes in paleogeography permitted range enlargement into new areas. Placoderm distributions in time and space indicate major faunal interchange between Gondwana and Laurussia near the Frasnian-Famennian boundary; closure of the Devonian equatorial ocean is a possible explanation.

Sequence stratigraphy and a revised sea-level curve for the Middle Devonian of eastern North America

Science.gov (United States)

Brett, Carlton E.; Baird, G.C.; Bartholomew, A.J.; DeSantis, M.K.; Ver Straeten, C.A.

2011-01-01

The well-exposed Middle Devonian rocks of the Appalachian foreland basin (Onondaga Formation; Hamilton Group, Tully Formation, and the Genesee Group of New York State) preserve one of the most detailed records of high-order sea-level oscillation cycles for this time period in the world. Detailed examination of coeval units in distal areas of the Appalachian Basin, as well as portions of the Michigan and Illinois basins, has revealed that the pattern of high-order sea-level oscillations documented in the New York-Pennsylvania section can be positively identified in all areas of eastern North America where coeval units are preserved. The persistence of the pattern of high-order sea-level cycles across such a wide geographic area suggests that these cycles are allocyclic in nature with primary control on deposition being eustatic sea-level oscillation, as opposed to autocylic controls, such as sediment supply, which would be more local in their manifestation. There is strong evidence from studies of cyclicity and spectral analysis that these cycles are also related to Milankovitch orbital variations, with the short and long-term eccentricity cycles (100. kyr and 405. kyr) being the dominant oscillations in many settings. Relative sea-level oscillations of tens of meters are likely and raise considerable issues about the driving mechanism, given that the Middle Devonian appears to record a greenhouse phase of Phanerozoic history. These new correlations lend strong support to a revised high-resolution sea-level oscillation curve for the Middle Devonian for the eastern portion of North America. Recognized third-order sequences are: Eif-1 lower Onondaga Formation, Eif-2: upper Onondaga and Union Springs formations; Eif-Giv: Oatka Creek Formation; Giv-1: Skaneateles, Giv-2: Ludlowville, Giv-3: lower Moscow, Giv-4: upper Moscow-lower Tully, and Giv-5: middle Tully-Geneseo formations. Thus, in contrast with the widely cited eustatic curve of Johnson et al. (1985), which

A new Late Devonian genus with seed plant affinities.

Science.gov (United States)

Wang, Deming; Liu, Le

2015-02-26

Many ovules of Late Devonian (Famennian) seed plants have been well studied. However, because few taxa occur with anatomically preserved stems and/or petioles, the vascular system of these earliest spermatophytes is little understood and available data come mostly from Euramerica. There remains great controversy over the anatomical differentiation of Late Devonian and Carboniferous seed plant groups of Buteoxylonales, Calamopityales and Lyginopteridales. Protostele evolution of these early spermatophytes needs more research. A new taxon Yiduxylon trilobum gen. et sp. nov. with seed plant affinities has been discovered in the Upper Devonian (Famennian) Tizikou Formation of Hubei Province, China. It is represented by stems, helically arranged and bifurcate fronds with two orders of pinnae and planate pinnules. Both secondary pinnae and pinnules are borne alternately. Stems contain a small protostele with three primary xylem ribs possessing a single peripheral protoxylem strand. Thick secondary xylem displays multiseriate bordered pitting on the tangential and radial walls of the tracheids, and has biseriate to multiseriate and high rays. A narrow cortex consists of inner cortex without sclerotic nests and sparganum-type outer cortex with peripheral bands of vertically aligned sclerenchyma cells. Two leaf traces successively arise tangentially from each primary xylem rib and they divide once to produce four circular-oval traces in the stem cortex. Four vascular bundles occur in two C-shaped groups at each petiole base with ground tissue and peripheral bands of sclerenchyma cells. Yiduxylon justifies the assignment to a new genus mainly because of the protostele with protoxylem strands only near the periphery of primary xylem ribs, leaf trace origination and petiolar vascular supply structure. It shares many definitive characters with Calamopityales and Lyginopteridales, further underscoring the anatomical similarities among early seed plants. The primary vascular

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2004-08-01

Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library are being sampled to collect CO{sub 2} adsorption isotherms. Sidewall core samples have been acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log has been acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 4.62 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 19 scf/ton in less organic-rich zones to more than 86 scf/ton in the Lower Huron Member of the shale. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2005-01-01

Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of the Devonian shales in Kentucky. Should the black shales of Kentucky prove to be a viable geologic sink for CO{sub 2}, their extensive occurrence in Paleozoic basins across North America would make them an attractive regional target for economic CO{sub 2} storage and enhanced natural gas production.

East Greenland tetrapods are Devonian in age

Science.gov (United States)

Marshall, J. E. A.; Astin, T. R.; Clack, J. A.

1999-07-01

Palynological dates unambiguously resolve the stratigraphic age of the East Greenland sedimentary rocks containing the earliest well-preserved tetrapod remains. This is the first time that spore samples have been discovered in the sedimentary succession that has yielded Acanthostega and Ichthyostega, two tetrapods that are regarded as critically important taxa for our understanding of the origin and early evolution of the tetrapods. These palynological assemblages conclusively show that the rocks are Devonian in age. The evidence resolves a 60-year-old dispute regarding the age of these rocks and contradicts a recent controversial study suggesting a much younger (Carboniferous, Viséan) age for these tetrapods. Spore samples bracketing the in situ occurrences of both tetrapod genera place them securely within the Famennian Age of the Devonian Period and at least as old as Famennian 2b. The ages of all known Devonian tetrapods are reviewed and related to a common palynological standard. This review places Ichthyostega and Acanthostega as the earliest of the Famennian tetrapods.

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

cherts on both Admiralty and Kupreanof Islands contain radiolarians as young as Permian, the age of the Cannery Formation is herein extended to Late Devonian through early Permian, to include the early Permian rocks exposed in its type locality. The Cannery Formation is folded and faulted, and its stratigraphic thickness is unknown but inferred to be several hundred meters. The Cannery Formation represents an extended period of marine deposition in moderately deep water, with slow rates of deposition and limited clastic input during Devonian through Pennsylvanian time and increasing argillaceous, volcaniclastic, and bioclastic input during the Permian. The Cannery Formation comprises upper Paleozoic rocks in the Alexander terrane of southeastern Alaska. In the pre-Permian upper Paleozoic, the tectonic setting of the Alexander terrane consisted of two or more evolved oceanic arcs. The lower Permian section is represented by a distinctive suite of rocks in the Alexander terrane, which includes sedimentary and volcanic rocks containing early Permian fossils, metamorphosed rocks with early Permian cooling ages, and intrusive rocks with early Permian cooling ages, that form discrete northwest-trending belts. After restoration of 180 km of dextral displacement of the Chilkat-Chichagof block on the Chatham Strait Fault, these belts consist, from northeast to southwest, of (1) bedded chert, siliceous argillite, volcaniclastic turbidites, pillow basalt, and limestone of the Cannery Formation and the Porcupine Slate of Gilbert and others (1987); (2) greenschist-facies Paleozoic metasedimentary and metavolcanic rocks that have Permian cooling ages; (3) silty limestone and calcareous argillite interbedded with pillow basalt and volcaniclastic rocks of the Halleck Formation and the William Henry Bay area; and (4) intermediate-composition and syenitic plutons. These belts correspond to components of an accretionary complex, contemporary metamorphic rocks, forearc-basin deposits,

The rise of fire: Fossil charcoal in late Devonian marine shales as an indicator of expanding terrestrial ecosystems, fire, and atmospheric change

Science.gov (United States)

Rimmer, Susan M.; Hawkins, Sarah J.; Scott, Andrew C.; Cressler, Walter L.

2015-01-01

Fossil charcoal provides direct evidence for fire events that, in turn, have implications for the evolution of both terrestrial ecosystems and the atmosphere. Most of the ancient charcoal record is known from terrestrial or nearshore environments and indicates the earliest occurrences of fire in the Late Silurian. However, despite the rise in available fuel through the Devonian as vascular land plants became larger and trees and forests evolved, charcoal occurrences are very sparse until the Early Mississippian where extensive charcoal suggests well-established fire systems. We present data from the latest Devonian and Early Mississippian of North America from terrestrial and marine rocks indicating that fire became more widespread and significant at this time. This increase may be a function of rising O2 levels and the occurrence of fire itself may have contributed to this rise through positive feedback. Recent atmospheric modeling suggests an O2 low during the Middle Devonian (around 17.5%), with O2 rising steadily through the Late Devonian and Early Mississippian (to 21–22%) that allowed for widespread burning for the first time. In Devonian-Mississippian marine black shales, fossil charcoal (inertinite) steadily increases up-section suggesting the rise of widespread fire systems. There is a concomitant increase in the amount of vitrinite (preserved woody and other plant tissues) that also suggests increased sources of terrestrial organic matter. Even as end Devonian glaciation was experienced, fossil charcoal continued to be a source of organic matter being introduced into the Devonian oceans. Scanning electron and reflectance microscopy of charcoal from Late Devonian terrestrial sites indicate that the fires were moderately hot (typically 500–600 °C) and burnt mainly surface vegetation dominated by herbaceous zygopterid ferns and lycopsids, rather than being produced by forest crown fires. The occurrence and relative abundance of fossil charcoal in

18 CFR 270.303 - Natural gas produced from Devonian shale.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Natural gas produced... DETERMINATION PROCEDURES Requirements for Filings With Jurisdictional Agencies § 270.303 Natural gas produced from Devonian shale. A person seeking a determination that natural gas is produced from Devonian shale...

DEVONIAN RUGOSE CORALS FROM THE KARAKORUM MOUNTAINS (NORTHERN PAKISTAN

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STEFAN SCHRÖDER

2004-11-01

Full Text Available The Karakorum Block is regarded as a microplate of "Gondwanan" origin and was part of the Cimmerian continent ("Mega Lhasa" which rifted away from the northern margin of Gondwana during the Late Palaeozoic/Early Mesozoic. From the Northern Karakorum Range (Yarkhun and Karambar River Valleys: structurally belonging to the Northern Sedimentary Belt an Upper Givetian to Lower Frasnian rugose coral fauna of the Shogram Formation is described. The fauna is dominated by cosmopolitan genera such as Hexagonaria, Disphyllum, Macgeea and the Temnophyllum/Spinophyllum group, generally showing a geographically wide distribution, although being absent from the Eastern Americas Realm in the Upper Givetian/Lower Frasnian. Therefore its components are of little use for biogeographical deductions at sub-realm level, and in explaining the relation between the Karakorum Range and other Cimmerian crustal blocks. A remarkable exception is the first record of the genus Pseudopexiphyllum outside of Turkey, indicating a connection to the western part of the Cimmerides. On species level, the coral fauna of the Shogram Formation is characterized by the development of a diverse and rather unique fauna including about 35 taxa, that differs from the faunas known from neighbouring crustal blocks. So far, faunistic links to the Central Iranian Microcontinent (Yazd-, and Tabas-Block, the northwest Iranian Plate (Elburz, Central Pamir, the Lhasa Block and Western Qiangtang are not clear, and although each of these fragments are believed to be closely connected they were apparently not in direct contact during the Devonian. However, the Karakorum fauna is remarkably close to one known from the Helmand Block in Afghanistan, showing a very similar generic composition that includes numerous morphologically closely related, although not identical species. Accordingly, the restricted faunal exchange led to the development of new taxa. Distribution of the new species of Spinophyllum

Lower Devonian Brachiopods and Stratigraphy of North Palencia (Cantabrian Mountains, Spain)

NARCIS (Netherlands)

Binnekamp, J.G.

1965-01-01

A continuous sequence of Devonian sediments is exposed in the northern part of the province of Palencia (NW-Spain), on the southern slope of the Cantabrian Mountains. This study concerns the stratigraphy and paleontology of the Lower Devonian formations. At the base of the sequence a clastic

Invasive species and biodiversity crises: testing the link in the late devonian.

Directory of Open Access Journals (Sweden)

Alycia L Stigall

Full Text Available During the Late Devonian Biodiversity Crisis, the primary driver of biodiversity decline was the dramatic reduction in speciation rates, not elevated extinction rates; however, the causes of speciation decline have been previously unstudied. Speciation, the formation of new species from ancestral populations, occurs by two primary allopatric mechanisms: vicariance, where the ancestral population is passively divided into two large subpopulations that later diverge and form two daughter species, and dispersal, in which a small subset of the ancestral population actively migrates then diverges to form a new species. Studies of modern and fossil clades typically document speciation by vicariance in much higher frequencies than speciation by dispersal. To assess the mechanism behind Late Devonian speciation reduction, speciation rates were calculated within stratigraphically constrained species-level phylogenetic hypotheses for three representative clades and mode of speciation at cladogenetic events was assessed across four clades in three phyla: Arthropoda, Brachiopoda, and Mollusca. In all cases, Devonian taxa exhibited a congruent reduction in speciation rate between the Middle Devonian pre-crisis interval and the Late Devonian crisis interval. Furthermore, speciation via vicariance is almost entirely absent during the crisis interval; most episodes of speciation during this time were due to dispersal. The shutdown of speciation by vicariance during this interval was related to widespread interbasinal species invasions. The lack of Late Devonian vicariance is diametrically opposed to the pattern observed in other geologic intervals, which suggests the loss of vicariant speciation attributable to species invasions during the Late Devonian was a causal factor in the biodiversity crisis. Similarly, modern ecosystems, in which invasive species are rampant, may be expected to exhibit similar shutdown of speciation by vicariance as an outcome of the

Invasive species and biodiversity crises: testing the link in the late devonian.

Science.gov (United States)

Stigall, Alycia L

2010-12-29

During the Late Devonian Biodiversity Crisis, the primary driver of biodiversity decline was the dramatic reduction in speciation rates, not elevated extinction rates; however, the causes of speciation decline have been previously unstudied. Speciation, the formation of new species from ancestral populations, occurs by two primary allopatric mechanisms: vicariance, where the ancestral population is passively divided into two large subpopulations that later diverge and form two daughter species, and dispersal, in which a small subset of the ancestral population actively migrates then diverges to form a new species. Studies of modern and fossil clades typically document speciation by vicariance in much higher frequencies than speciation by dispersal. To assess the mechanism behind Late Devonian speciation reduction, speciation rates were calculated within stratigraphically constrained species-level phylogenetic hypotheses for three representative clades and mode of speciation at cladogenetic events was assessed across four clades in three phyla: Arthropoda, Brachiopoda, and Mollusca. In all cases, Devonian taxa exhibited a congruent reduction in speciation rate between the Middle Devonian pre-crisis interval and the Late Devonian crisis interval. Furthermore, speciation via vicariance is almost entirely absent during the crisis interval; most episodes of speciation during this time were due to dispersal. The shutdown of speciation by vicariance during this interval was related to widespread interbasinal species invasions. The lack of Late Devonian vicariance is diametrically opposed to the pattern observed in other geologic intervals, which suggests the loss of vicariant speciation attributable to species invasions during the Late Devonian was a causal factor in the biodiversity crisis. Similarly, modern ecosystems, in which invasive species are rampant, may be expected to exhibit similar shutdown of speciation by vicariance as an outcome of the modern biodiversity

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2003-02-10

Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2003-04-28

Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2003-02-11

Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, strategy is to inject CO{sub 2} into organic-rich shales of Devonian age. Devonian black shales underlie approximately two-thirds of Kentucky and are generally thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to the way methane is stored in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane at a ratio of two to one. Black shales may similarly desorb methane in the presence of CO{sub 2}. If black shales similarly desorb methane in the presence of CO{sub 2}, the shales may be an excellent sink for CO{sub 2} with the added benefit of serving to enhance natural gas production. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject this research. To accomplish this investigation, drill cuttings and cores will be selected from the Kentucky Geological Survey Well Sample and Core Library. CO{sub 2} adsorption analyses will be performed in order to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, new drill cuttings and sidewall core samples will be acquired to investigate specific black-shale facies, their uptake of CO{sub 2}, and the resultant displacement of methane. Advanced logging techniques (elemental capture spectroscopy) will be used to investigate possible correlations between adsorption capacity and geophysical log measurements.

Dolomitization and sedimentary cyclicity of the Ordovician, Silurian, and Devonian rocks in South Estonia

Directory of Open Access Journals (Sweden)

Kallaste, Toivo

2006-03-01

Full Text Available The distribution and composition of dolomitized rocks and stoichiometry of dolomite in southern Estonia in the Ordovician, Silurian, and Devonian were studied on the background of the facies, sedimentary cyclicity (nine shallowing-up cycles, and evolution of the palaeobasins. The composition of rocks and lattice parameters of dolomite were investigated using the X-ray diffraction, X-ray fluorescence, titration and gravimetric analyses, and porosity measurements. The formation of dolostones is directly determined by the cyclic evolution of palaeobasins. Dolomitized rocks belong to the shallow-water inner shelf or tidal/lagoonal facies belt of regressive phases of sedimentary cycles. Sediments of the deep shelf/transitional environment and transgressive phases are not dolomitized. The most stoichiometric is secondary replacive dolomite of Silurian and upper Ordovician dolostones, formed during the early diagenesis of normal-marine (saline shallow-shelf calcitic sediments. The content of insoluble residue does not affect the stoichiometry. The changes in lattice parameters are induced by the Ca/Mg ratio in the dolomite lattice. The dolomite of the dolostones contacting limestone or containing calcite has an expanded lattice. The primary (syngenetic dolostone of the lagoonal or tidal flat belt has also an expanded lattice. No dolomitizing effect of the waters of the Devonian palaeobasin on the underlying rocks was revealed. The whole data set of the studied dolostones is consistent with the marine water environment in the palaeobasin at the corresponding time and shows no sign of the inflow of external fluids. It suggests that the microbial model of dolomite formation may characterize the Ordovician, Silurian, and Devonian in southern Estonia. The occurrence of dolostones between undolomitized rocks limits the time of dolomitization to the early diagenetic stage.

Hydrogeologic characterization of devonian aquifers in Uruguay

International Nuclear Information System (INIS)

Massa, E.

1988-01-01

This article carried out the assistance research project implementation in devonian sedimentary units as a potentials aquifers and their best use to school supplying and rural population in central area of Uruguay.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2003-10-29

CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf/ton) of

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2004-04-01

CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 percent (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2004-01-01

CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. For the Devonian shale, average total organic carbon is 3.71 (as received) and mean random vitrinite reflectance is 1.16. Measured adsorption isotherm data range from 37.5 to 2,077.6 standard cubic feet of CO{sub 2} per ton (scf/ton) of

Survey of the upper Frasnian reefs: a priority exploratory operation in the Volgograd Oblast

Energy Technology Data Exchange (ETDEWEB)

Shakhnovskii, I.M.; Nikishin, A.G.; Lezhnev, V.M.

1978-01-01

A description is given of the first oil fields - the Kotov and Miroshnikov, identified in the upper Frasnian structures of reef origin in the western rim of the Umetov--Linev depression. An identification is made of survey criteria that can be used in the exploration of upper Devonian structures of reef origin. Substantiation is offered for further exploratory and survey operations in the Volgograd Oblast. 2 figures.

Environmental conditions as the cause of the great mass extinction of marine organisms in the Late Devonian

Science.gov (United States)

Barash, M. S.

2017-08-01

During the Late Devonian extinction, 70-82% of all marine species disappeared. The main causes of this mass extinction include tectonic activity, climate and sea-level fluctuations, volcanism, and the collision of the Earth with cosmic bodies (impact events). The major causes are considered to be volcanism accompanying formation of the Viluy traps and, probably, basaltic magmatism in the Southern Urals, alkaline magmatism within the East European platform, and volcanism in northern Iran and northern and southern China. Several large impact craters of Late Devonian age have been documented in different parts of the world. The available data indicate that this time period on the Earth was marked by two major sequences of events: terrestrial events that resulted in extensive volcanism and cosmic (or impact) events. They produced similar effects such as emissions of harmful chemical compounds and aerosols to cause greenhouse warming and the darkening of the atmosphere, which prevented photosynthesis and cause ocean stagnation and anoxia. This disrupted the food chain and reduced ecosystem productivity. As a result, all vital processes were disturbed and a large part of the marine biota became extinct.

Sequence stratigraphy from ``spot'' outcrops—example from a carbonate-dominated setting: Devonian-Carboniferous transition, Dinant synclinorium (Belgium)

Science.gov (United States)

Van Steenwinkel, M.

1990-12-01

The application of sequence stratigraphy appears to be perfectly valid in isolated "spot" outcrops, which usually are badly exposed and located in areas of strong tectonic overprint. The case study presented here is in a carbonate-dominated setting at the northern edge of the Cornwall-Rhenish basin, during latest Devonian and earliest Carboniferous times. The approach taken involved the analysis of facies and vertical facies evolutions, in combination with detailed biostratigraphy. The subsequent deduction of deepening and shallowing events, and the understanding of the sedimentary response to these events in different palaeogeographical positions, are the basis for lateral correlation of facies sequences. A similar trend in the changes of deepenings and shallowings throughout the area, regardless of lateral facies differentiation, indicates a relationship between bathymetric changes and relative sea-level changes, that is independent of local differences in the sedimentation or subsidence rates. The studied stratigraphic interval, with its apparently "abrupt" changes in facies or lithology, is the sedimentary response to six, gradually changing trends in the rate of relative sea-level fall and rise. End-Devonian, offshore highstand deposits (1) are capped by an unconformity surface or by a surface of submarine erosion and nondeposition, representing a sequence boundary (2). The overlying lowstand unit consists of a basal (3) and an upper (4) part. The basal part contains an oolitic and crinoidal sand shoals, associated with a transgressive lag deposit in offshore position; the upper, main part is a prograding wedge of shallow-marine crinoidal sands, intercalated with increasingly deeper-water shaly facies (higher-order fluctuation). This lowstand unit was deposited during the initial, slow phase of relative sea-level rise. It levelled the topographic relief before the final drowning during the subsequent rapid (near the rise inflection point) relative sea

Stable isotope analysis of Dacryoconarid carbonate microfossils: a new tool for Devonian oxygen and carbon isotope stratigraphy.

Science.gov (United States)

Frappier, Amy Benoit; Lindemann, Richard H; Frappier, Brian R

2015-04-30

Dacryoconarids are extinct marine zooplankton known from abundant, globally distributed calcite microfossils in the Devonian, but their shell stable isotope composition has not been previously explored. Devonian stable isotope stratigraphy is currently limited to less common invertebrates or bulk rock analyses of uncertain provenance. As with Cenozoic planktonic foraminifera, isotopic analysis of dacryoconarid shells could facilitate higher-resolution, geographically widespread stable isotope records of paleoenvironmental change, including marine hypoxia events, climate changes, and biocrises. We explored the use of Dacryoconarid isotope stratigraphy as a viable method in interpreting paleoenvironments. We applied an established method for determining stable isotope ratios (δ(13) C, δ(18) O values) of small carbonate microfossils to very well-preserved dacryoconarid shells. We analyzed individual calcite shells representing five common genera using a Kiel carbonate device coupled to a MAT 253 isotope ratio mass spectrometer. Calcite shell δ(13) C and δ(18) O values were compared by taxonomic group, rock unit, and locality. Single dacryoconarid calcite shells are suitable for stable isotope analysis using a Kiel-IRMS setup. The dacryoconarid shell δ(13) C values (-4.7 to 2.3‰) and δ(18) O values (-10.3 to -4.8‰) were consistent across taxa, independent of shell size or part, but varied systematically through time. Lower fossil δ(18) O values were associated with warmer water temperature and more variable δ(13) C values were associated with major bioevents. Dacryoconarid δ(13) C and δ(18) O values differed from bulk rock carbonate values. Dacryoconarid individual microfossil δ(13) C and δ(18) O values are highly sensitive to paleoenvironmental changes, thus providing a promising avenue for stable isotope chemostratigraphy to better resolve regional to global paleoceanographic changes throughout the upper Silurian to the upper Devonian. Our results

The axial skeleton of the Devonian tetrapod Ichthyostega.

Science.gov (United States)

Ahlberg, Per Erik; Clack, Jennifer A; Blom, Henning

2005-09-01

Ichthyostega was the first Devonian tetrapod to be subject to a whole-body reconstruction. It remains, together with Acanthostega, one of only two Devonian tetrapods for which near-complete postcranial material is available. It is thus crucially important for our understanding of the earliest stages of tetrapod evolution and terrestrialization. Here we show a new reconstruction of Ichthyostega based on extensive re-examination of original material and augmented by recently collected specimens. Our reconstruction differs substantially from those previously published and reveals hitherto unrecognized regionalization in the vertebral column. Ichthyostega is the earliest vertebrate to show obvious adaptations for non-swimming locomotion. Uniquely among early tetrapods, the presacral vertebral column shows pronounced regionalization of neural arch morphology, suggesting that it was adapted for dorsoventral rather than lateral flexion.

Sedimentology and facies analysis of Devonian Rocks, southern district of Mackenzie, North West Territories, Canada

NARCIS (Netherlands)

Meijer Drees, N.C.

1989-01-01

The Devonian rock succession in the southern part of the District of Mackenzie consists of interbedded evaporites and carbonates, fossiliferous carbonates and shales. Inthe study areathe Devonian succession unconformably overlies LowerPaleozoic orPrecambrian strata and thins in a northeastward

Devonian alkaline magmatic belt along the northern margin of the North China Block: Petrogenesis and tectonic implications

Science.gov (United States)

Zhang, Qi-Qi; Zhang, Shuan-Hong; Zhao, Yue; Liu, Jian-Min

2018-03-01

Some Devonian magmatic rocks have been identified from the northern margin of the North China Block (NCB) in recent years. However, their petrogenesis and tectonic setting are still highly controversial. Here we present new geochronological, Sr-Nd-Hf isotopic and whole-rock chemical data on several newly identified and previously reported Devonian alkaline complexes, including mafic-ultramafic rocks (pyroxenites and gabbros), alkaline rocks (syenites, monzonites) and alkaline granites in the northern NCB. We firstly identified some mafic-ultramafic rocks coeval with monzonite and quartz monzonite in the Sandaogou and Wulanhada alkaline intrusions. New zircon U-Pb dating of 16 samples from the Baicaigou, Gaojiacun, Sandaogou, Wulanhada and Chifeng alkaline intrusions combined with previous geochronological results indicate that the Devonian alkaline rocks emplaced during the early-middle Devonian at around 400-380 Ma and constitute an E-W-trending alkaline magmatic belt that extend ca. 900 km long along the northern margin of the NCB. Whole-rock geochemical and Sr-Nd-Hf isotopic data reveal that the Devonian alkaline rocks were mainly originated from partial melting of a variably enriched lithospheric mantle with different involvement of ancient lower crustal component and fractional crystallization. The Devonian alkaline magmatic belt rocks in the northern NCB are characterized by very weak or no deformations and were most likely related to post-collision extension after arc-continent collision between the Bainaimiao island arc and the northern margin of North China Craton during the latest Silurian. Partial melting of subcontinental lithospheric mantle to produce the Devonian alkaline magmatic rocks suggests that the northern North China Craton has an inhomogeneous, variably enriched subcontinental lithospheric mantle and was characterized by significant vertical crustal growth during the Devonian period.

ANALYSIS OF DEVONIAN BLACK SHALES IN KENTUCKY FOR POTENTIAL CARBON DIOXIDE SEQUESTRATION AND ENHANCED NATURAL GAS PRODUCTION

Energy Technology Data Exchange (ETDEWEB)

Brandon C. Nuttall

2003-07-28

CO{sub 2} emissions from the combustion of fossil fuels have been linked to global climate change. Proposed carbon management technologies include geologic sequestration of CO{sub 2}. A possible, but untested, sequestration strategy is to inject CO{sub 2} into organic-rich shales. Devonian black shales underlie approximately two-thirds of Kentucky and are thicker and deeper in the Illinois and Appalachian Basin portions of Kentucky than in central Kentucky. The Devonian black shales serve as both the source and trap for large quantities of natural gas; total gas in place for the shales in Kentucky is estimated to be between 63 and 112 trillion cubic feet. Most of this natural gas is adsorbed on clay and kerogen surfaces, analogous to methane storage in coal beds. In coals, it has been demonstrated that CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. The concept that black, organic-rich Devonian shales could serve as a significant geologic sink for CO{sub 2} is the subject of current research. To accomplish this investigation, drill cuttings and cores were selected from the Kentucky Geological Survey Well Sample and Core Library. Methane and carbon dioxide adsorption analyses are being performed to determine the gas-storage potential of the shale and to identify shale facies with the most sequestration potential. In addition, sidewall core samples are being acquired to investigate specific black-shale facies, their potential CO{sub 2} uptake, and the resulting displacement of methane. Advanced logging techniques (elemental capture spectroscopy) are being investigated for possible correlations between adsorption capacity and geophysical log measurements. Initial estimates indicate a sequestration capacity of 5.3 billion tons CO{sub 2} in the Lower Huron Member of the Ohio shale in parts of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker portions of the

Seawater strontium isotope curve at the Silurian/Devonian boundary: a study of the global Silurian/Devonian boundary stratotype

Czech Academy of Sciences Publication Activity Database

Frýda, J.; Hladil, Jindřich; Vokurka, K.

2002-01-01

Roč. 35, č. 1 (2002), s. 21-28 ISSN 0016-6995 R&D Projects: GA ČR GA205/98/0454; GA ČR GA205/01/0143 Institutional research plan: CEZ:AV0Z3013912 Keywords : strontium chemostratigraphy * Silurian/Devonian * Barrandian area Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.410, year: 2002

Climate effects caused by land plant invasion in the Devonian

Science.gov (United States)

Hir guillaume, Le; yannick, Donnadieu; yves, Goddéris; brigitte, Meyer-Berthaud; gilles, Ramstein

2017-04-01

Land plants invaded continents during the Mid-Paleozoic. Their spreading and diversification have been compared to the Cambrian explosion in terms of intensity and impact on the diversification of life on Earth. Whereas prior studies were focused on the evolution of the root system and its weathering contribution, here we investigated the biophysical impacts of plant colonization on the surface climate through changes in continental albedo, roughness, thermal properties, and potential evaporation using a 3D-climate model coupled to a global biogeochemical cycles associated to a simple model for vegetation dynamics adapted to Devonian conditions. From the Early to the Late Devonian, we show that continental surface changes induced by land plants and tectonic drift have produced a large CO2 drawdown without being associated to a global cooling, because the cooling trend is counteracted by a warming trend resulting from the surface albedo reduction. If CO2 is consensually assumed as the main driver of the Phanerozoic climate, during land-plant invasion, the modifications of soil properties could have played in the opposite direction of the carbon dioxide fall, hence maintaining warm temperatures during part of the Devonian.

Root evolution at the base of the lycophyte clade: insights from an Early Devonian lycophyte

Science.gov (United States)

Matsunaga, Kelly K. S.; Tomescu, Alexandru M. F.

2016-01-01

Background and Aims The evolution of complex rooting systems during the Devonian had significant impacts on global terrestrial ecosystems and the evolution of plant body plans. However, detailed understanding of the pathways of root evolution and the architecture of early rooting systems is currently lacking. We describe the architecture and resolve the structural homology of the rooting system of an Early Devonian basal lycophyte. Insights gained from these fossils are used to address lycophyte root evolution and homology. Methods Plant fossils are preserved as carbonaceous compressions at Cottonwood Canyon (Wyoming), in the Lochkovian–Pragian (∼411 Ma; Early Devonian) Beartooth Butte Formation. We analysed 177 rock specimens and documented morphology, cuticular anatomy and structural relationships, as well as stratigraphic position and taphonomic conditions. Key Results The rooting system of the Cottonwood Canyon lycophyte is composed of modified stems that bear fine, dichotomously branching lateral roots. These modified stems, referred to as root-bearing axes, are produced at branching points of the above-ground shoot system. Root-bearing axes preserved in growth position exhibit evidence of positive gravitropism, whereas the lateral roots extend horizontally. Consistent recurrence of these features in successive populations of the plant preserved in situ demonstrates that they represent constitutive structural traits and not opportunistic responses of a flexible developmental programme. Conclusions This is the oldest direct evidence for a rooting system preserved in growth position. These rooting systems, which can be traced to a parent plant, include some of the earliest roots known to date and demonstrate that substantial plant–substrate interactions were under way by Early Devonian time. The morphological relationships between stems, root-bearing axes and roots corroborate evidence that positive gravitropism and root identity were evolutionarily

Evolution of an intra-oceanic island arc during the late Silurian to late Devonian, New England fold belt

International Nuclear Information System (INIS)

Offler, R.; Gamble, J.

2002-01-01

Geochemical studies of volcanic rocks in the Gamilaroi terrane and Calliope Volcanic Assemblage, New England Fold Belt, eastern Australia, indicate that the setting in which these rocks formed changed in both space and time. The Upper Silurian to Middle Devonian basalts of the Gamilaroi terrane show flat to slightly light rare-earth element (LREE) depleted chondrite normalised patterns, depletion of high field strength elements (HFSE) relative to N-MORB, low Ti/V and high Ti/Zr ratios, high Ni, Cr and large-ion lithophile element (LILE) contents, features characteristic of intra-oceanic island arc basaltic magmas. They are associated with low-K, less mafic volcanics, showing moderate LREE enrichment, low Nb and Y contents and Rb/Zr ratios. The depletion of HFSE in the basalts indicates that the magmas were derived from a refractory source in a supra-subduction zone setting. The presence of such a zone implies that the arc was associated with a backarc basin, the location of which was to the west where a wide backarc region existed from the Middle Silurian. This polarity of arc and backarc basin suggests that the subduction zone dipped to the west. In contrast to their older counterparts, Middle to Upper Devonian basalts of the Gamilaroi terrane have MORB-like chondrite normalised patterns and higher Ti and lower LILE contents. Moreover, they have low Ti/Zr ratios and MORB-like Ti/V ratios and HFSE contents, features typical of backarc basins. Dolerites of the Gamilaroi terrane also have predominantly backarc basin signatures. These features suggest that both the basalts and dolerites have been emplaced in an extensional environment produced during the rifting of the intra-oceanic island arc lithosphere. A progressive increase in Ti/V ratios, and TiO 2 and Fe 2 O 3 contents at constant MgO, of stratigraphically equivalent basalts, towards the north-northwest part of the belt, is consistent with either greater extension to the north or melting of a more fertile magma

Density characteristics in the upper part of the platform of the Pripyatskiy Basin

Energy Technology Data Exchange (ETDEWEB)

Bulyga, V.K.; Anpilogov, A.P.; Ksenofontov, V.A.; Ur' yev, I.I.

1981-01-01

Density characteristics are examined for the Devonian (upper saline and suprasaline), Carboniferous, Permian, Mesozoic and Cenozoic deposits of the Pripyatskiy Basin. Maps are compiled for isodensities, variability is established in the average values of density both in a regional sense and on local elevations which are characterized for the most part by density minimums.

Silurian and Devonian source rocks and crude oils from the western part of Libya: Organic geochemistry, palynology and carbon stratigraphy

NARCIS (Netherlands)

Elkelani, Mohamed M.A.

2015-01-01

The Early Silurian “hot” shales and Late Devonian black shales are major regional oil and gas source rocks in North Africa. Their deposition probably played a major role in global carbon cycling in general because of the large areas of the ocean affected. Comparing the Libyan δ13C record with

Devonian magmatism in the Timan Range, Arctic Russia - subduction, post-orogenic extension, or rifting?

Science.gov (United States)

Pease, V.; Scarrow, J. H.; Silva, I. G. Nobre; Cambeses, A.

2016-11-01

Devonian mafic magmatism of the northern East European Craton (EEC) has been variously linked to Uralian subduction, post-orogenic extension associated with Caledonian collision, and rifting. New elemental and isotopic analyses of Devonian basalts from the Timan Range and Kanin Peninsula, Russia, in the northern EEC constrain magma genesis, mantle source(s) and the tectonic process(es) associated with this Devonian volcanism to a rift-related context. Two compositional groups of low-K2O tholeiitic basalts are recognized. On the basis of Th concentrations, LREE concentrations, and (LREE/HREE)N, the data suggest two distinct magma batches. Incompatible trace elements ratios (e.g., Th/Yb, Nb/Th, Nb/La) together with Nd and Pb isotopes indicate involvement of an NMORB to EMORB 'transitional' mantle component mixed with variable amounts of a continental component. The magmas were derived from a source that developed high (U,Th)/Pb, U/Th and Sm/Nd over time. The geochemistry of Timan-Kanin basalts supports the hypothesis that the genesis of Devonian basaltic magmatism in the region resulted from local melting of transitional mantle and lower crust during rifting of a mainly non-volcanic continental rifted margin.

EARLY ORDOVICIAN AND DEVONIAN CONODONTS FROM THE WESTERN KARAKORAM AND HINDU KUSH, NORTHERNMOST PAKISTAN

Directory of Open Access Journals (Sweden)

JOHN A. TALENT

1999-07-01

Full Text Available Extensive tracts of Devonian and older sedimentary and igneous units occur within the axial region of the western Karakoram Block of northernmost Pakistan over a distance in excess of 200 km between the the headwaters of the Karambar valley in northwestern Gilgit Agency to southwestern Chitral. Conodont data indicate that the oldest sedimentary unit so far discriminated within this belt, the Yarkhun Formation, includes horizons of Ordovician (Arenig age, consistent with an earlier-presented acritarch-based Arenig age for part of the same unit. Conodont data from the "Lun Shales", a stratigraphic potpourri with little-known Silurian and Devonian tracts, demonstrate the presence of Early Devonian (early Emsian horizons. The Shogrâm Formation, widely distributed through the region, spans an appreciable interval of the Middle and Late Devonian mid-Givetian through until at least early Famennian. A major lacuna in sedimentation may be present, represented by all or most of the earlier half of Frasnian time. A biostratigraphically and possibly biogeographically important new species, Icriodus homeomorphus, is described; it is encountered in horizons of early Famennian age (Late triangularis Zone to ?Early crepida Zone. 

Hydrogeology and simulation of ground-water flow in the Silurian-Devonian aquifer system, Johnson County, Iowa

Science.gov (United States)

Tucci, Patrick; McKay, Robert M.

2006-01-01

Bedrock of Silurian and Devonian age (termed the “Silurian-Devonian aquifer system”) is the primary source of ground water for Johnson County in east-central Iowa. Population growth within municipal and suburban areas of the county has resulted in increased amounts of water withdrawn from this aquifer and water-level declines in some areas. A 3-year study of the hydrogeology of the Silurian-Devonian aquifer system in Johnson County was undertaken to provide a quantitative assessment of ground water resources and to construct a ground-water flow model that can be used by local governmental agencies as a management tool.

The first direct evidence of a Late Devonian coelacanth fish feeding on conodont animals

OpenAIRE

Zaton, M.; Broda, K.; Qvarnström, M.; Niedzwiedzki, G.; Ahlberg, P.E.

2017-01-01

We describe the first known occurrence of a Devonian coelacanth specimen from the lower Famennian of the Holy Cross Mountains, Poland, with a conodont element preserved in its digestive tract. A small spiral and phosphatic coprolite (fossil excrement) containing numerous conodont elements and other unrecognized remains was also found in the same deposits. The coprolite is tentatively attributed to the coelacanth. Although it is unclear whether the Late Devonian coelacanth from Poland was an a...

Association between catastrophic paleovegetation changes during Devonian-Carboniferous boundary and the formation of giant massive sulfide deposits

Science.gov (United States)

Menor-Salván, Cesar; Tornos, Fernando; Fernández-Remolar, David; Amils, Ricardo

2010-11-01

The Iberian Pyrite Belt (SW Iberia) is one of the largest sulfur anomalies in the Earth's crust. In the southern Iberian Pyrite Belt, more than 820 Mt of exhalative massive sulfides were deposited in less than one million years at the Devonian-Carboniferous boundary. The shale of the ore-bearing horizon contains biomarkers indicating major biogenic activity in a methanogenic setting, including a five-fold increase in typical vascular plant biomarkers and a significant anomaly in those probably indicating the presence of thermophilic Archaea. This contrasts with signatures in the average sedimentary rocks of the basin that indicate the sediments settled in oxic to sub-oxic environments, and that they have only minor biomarkers derived from continental paleoflora. These data show that the formation of the mineralization was not only related to major hydrothermal activity synchronous with volcanism but may also have been controlled by the input of large amounts of organic matter, mostly derived from the degradation of woodland detritus sourced in the nearby continent. This massive influx of organic matter could have accelerated extremophilic microbial activity that used short-chain hydrocarbons as electron donors for seawater sulfate reduction, resulting in concomitant massive sulfide precipitation. We propose that the giant massive sulfide deposits resulted from overlapping of geological and biological processes that occurred at the Devonian to Carboniferous transition, including: (1) continent collision during the onset of the Variscan orogeny leading to major paleogeographic changes and volcanism; (2) dramatic stress of continental ecosystems due to the combination of climatic change, volcanism, variations in the sea level and erosion on a regional scale; (3) major biomass destruction and increase of organic supply to marine environments; and, (4) generation of anoxic conditions and the thriving of sulfate reducing microorganisms. Under these conditions, massive

Source rock potential of the organic rich Turonian - Upper Campanian carbonates of northern Lebanon

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Daher, S. Bou; Littke, R. [RWTH Aachen Univ. (Germany). Energy and Mineral Resources Group (EMR); Nader, F.H. [IFP Energies nouvelles, Paris (France). Dept. of Sedimentology-Stratigraphy

2013-08-01

Upper Cretaceous chalks, marls, and shales are arguably the most prolific petroleum source rocks in the eastern Mediterranean region. 209 core samples from the Turonian - Upper Campanian rock succession in north Lebanon were collected and analyzed for their organic matter (OM) content, quality, and maturity. The total organic carbon (TOC) measurements revealed a very good source rock potential for a 150 m interval within the Upper Santonian - Upper Campanian, with an average of 2% TOC. High HI values (average 707 mg/g TOC) characterize these source rocks as type I kerogen and reflect a very good preservation of the organic matter. T{sub max} values (average 421 C) match the other maturity parameters such as vitrinite reflectance (average 0.35%), and all point towards immature organic matter. The equivalent Upper Cretaceous in the offshore Levant basin has enough overburden to have reached maturity. However, the accurate extrapolation of the organic matter quality and quantity to the offshore is yet a challenge with the data at hand. (orig.)

Soil development on loess overlying Cretaceous sediments and Devonian limestones

Czech Academy of Sciences Publication Activity Database

Žigová, Anna; Šťastný, Martin

2015-01-01

Roč. 12, č. 3 (2015), s. 267-278 ISSN 1214-9705 Institutional support: RVO:67985831 Keywords : loess * Cretaceous and Devonian rocks * mineral composition * soil development * Luvic Chernozem * Albic Luvisol Subject RIV: DF - Soil Science Impact factor: 0.561, year: 2015

Devonian and Lower Carboniferous conodont biostratigraphy, Spanish Central Pyrenees

NARCIS (Netherlands)

Boersma, Kerst Th.

1973-01-01

Conodont faunas were collected from the Devonian and Lower Carboniferous in an area ranging from the Rio Fsera (prov. of Huesca) in the west to the Rio Llobregat (prov. of Barcelona) in the east. Most conodont zones and -Faunas recognized in Germany and Spain could be distinguished. The ages of the

End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates.

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Sallan, Lauren Cole; Coates, Michael I

2010-06-01

The Devonian marks a critical stage in the early evolution of vertebrates: It opens with an unprecedented diversity of fishes and closes with the earliest evidence of limbed tetrapods. However, the latter part of the Devonian has also been characterized as a period of global biotic crisis marked by two large extinction pulses: a "Big Five" mass extinction event at the Frasnian-Famennian stage boundary (374 Ma) and the less well-documented Hangenberg event some 15 million years later at the Devonian-Carboniferous boundary (359 Ma). Here, we report the results of a wide-ranging analysis of the impact of these events on early vertebrate evolution, which was obtained from a database of vertebrate occurrences sampling over 1,250 taxa from 66 localities spanning Givetian to Serpukhovian stages (391 to 318 Ma). We show that major vertebrate clades suffered acute and systematic effects centered on the Hangenberg extinction involving long-term losses of over 50% of diversity and the restructuring of vertebrate ecosystems worldwide. Marine and nonmarine faunas were equally affected, precluding the existence of environmental refugia. The subsequent recovery of previously diverse groups (including placoderms, sarcopterygian fish, and acanthodians) was minimal. Tetrapods, actinopterygians, and chondrichthyans, all scarce within the Devonian, undergo large diversification events in the aftermath of the extinction, dominating all subsequent faunas. The Hangenberg event represents a previously unrecognized bottleneck in the evolutionary history of vertebrates as a whole and a historical contingency that shaped the roots of modern biodiversity.

Petrographic Evidence of Microbial Mats in the Upper Cretaceous Fish-Bearing, Organic-Rich Limestone, Agua Nueva Formation, Central Mexico

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Blanco, A.; Maurrasse, F. J.; Hernández-Ávila, J.; Ángeles-Trigueros, S. A.; García-Cabrera, M. E.

2013-05-01

We document petrographic evidence of microbial mats in the Upper Cretaceous Agua Nueva Formation in the area of Xilitla (San Luis Potosí, Central Mexico), located in the southern part of the Tampico-Misantla basin. The sequence consists predominantly of alternating decimeter-thick beds of fossiliferous dark laminated limestone (C-org > 1.0wt%), and light gray, bioturbated limestone (C-org Duque-Botero and Maurrasse, 2005; 2008). These structures are also analogous to microbial mats in present environments, and Devonian deposits (Kremer, 2006). In addition, the laminae at Xilitla include filamentous bacterial structures, as thin and segmented red elements. In some thin sections, filaments appear to be embedded within the crinkly laminae and shreds showing the same pattern of folding, suggestive of biomorphic elements that represent the main producers of the organic matter associated with the laminae. Thus, exceptional bacterial activity characterizes sedimentation during the accumulation of the Agua Nueva Formation. Oxygen-deficient conditions related to the microbial mats were an important element in the mass mortality and preservation of the fish assemblages. Absence of bioturbation, pervasive framboidal pyrite, and the high concentration of organic matter (TOC ranges from 1.2% to 8wt%) in the dark limestones are consistent with persistent recurring dysoxic/anoxic conditions, and the light-gray bioturbated limestones represent relatively well-oxygenated episodes. Planktonic foraminifera (Rotalipora cushmani) and Inoceramu labiatus indicate a time interval from the latest Cenomanian through the earliest Turonian, thus this long interval of severe oxygen deficiency is coeval with Oceanic Anoxic Event 2 (OAE-2). [Duque-Botero and Maurrasse. 2005. Jour. Iberian Geology (31), 85-98; 2008. Cret. Res., 29, 957-964; Kremer. 2006. Acta Palaeontologica Polonica (51, 1), 143-154

Depositional environment and organic matter accumulation of Upper Ordovician–Lower Silurian marine shale in the Upper Yangtze Platform, South China

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Li, Yangfang; Zhang, Tongwei; Ellis, Geoffrey S.; Shao, Deyong

2017-01-01

The main controlling factors of organic matter accumulation in the Upper Ordovician Wufeng–Lower Silurian Longmaxi Formations are complex and remain highly controversial. This study investigates the vertical variation of total organic carbon (TOC) content as well as major and trace element concentrations of four Ordovician–Silurian transition sections from the Upper Yangtze Platform of South China to reconstruct the paleoenvironment of these deposits and to improve our understanding of those factors that have influenced organic matter accumulation in these deposits.The residual TOC content of the Wufeng Formation averages 3.2% and ranges from 0.12 to 6.0%. The overlying lower Longmaxi Formation displays higher TOC content (avg. 4.4%), followed upsection by consistent and lower values that average 1.6% in the upper Longmaxi Formation. The concentration and covariation of redox-sensitive trace elements (Mo, U and V) suggest that organic-rich intervals of the Wufeng Formation accumulated under predominantly anoxic conditions. Organic-rich horizons of the lower Longmaxi Formation were deposited under strongly anoxic to euxinic conditions, whereas organic-poor intervals of the upper Longmaxi Formation accumulated under suboxic conditions. Positive correlations between redox proxies and TOC contents suggest that organic matter accumulation was predominantly controlled by preservation. Barium excess (Baxs) values indicate high paleoproductivity throughout the entire depositional sequence, with an increase in the lower Longmaxi Formation. Increased productivity may have been induced by enhanced P recycling, as evidenced by elevated Corg/Ptot ratios. Mo–U covariation and Mo/TOC values reveal that the Wufeng Formation was deposited under extremely restricted conditions, whereas the Longmaxi Formation accumulated under moderately restricted conditions. During the Late Ordovician, the extremely restricted nature of ocean circulation on the Upper Yangtze Platform in

The global stratotype section and point of the Silurian-Devonian boundary

Czech Academy of Sciences Publication Activity Database

Chlupáč, I.; Hladil, Jindřich

2000-01-01

Roč. 225, - (2000), s. 1-6+1 Pl. ISSN 0341-4116 Institutional research plan: CEZ:AV0Z3013912 Keywords : Silurian-Devonian * global stratotype section and point (GSSP) * stratigraphy Subject RIV: DB - Geology ; Mineralogy

Formation evaluation in Devonian shale through application of new core and log analysis methods

International Nuclear Information System (INIS)

Luffel, D.L.; Guidry, F.K.

1990-01-01

In the Devonian shale of the Appalachian Basin all porosity in excess of about 2.5 percent is generally occupied by free hydrocarbons, which is mostly gas, based on results of new core and log analysis methods. In this study, sponsored by the Gas Research Institute, reservoir porosities averaged about 5 percent and free gas content averaged about 2 percent by bulk volume, based on analyses on 519 feet of conventional core in four wells. In this source-rich Devonian shale, which also provides the reservoir storage, the rock everywhere appears to be at connate, or irreducible, water saturation corresponding to two or three percent of bulk volume. This became evident when applying the new core and log analysis methods, along with a new plotting method relating bulk volume of pore fluids to porosity. This plotting method has proved to be a valuable tool: it provides useful insight on the fluid distribution present in the reservoir, it provides a clear idea of porosity required to store free hydrocarbons, it leads to a method of linking formation factor to porosity, and it provides a good quality control method to monitor core and log analysis results. In the Devonian shale an important part of the formation evaluation is to determine the amount of kerogen, since this appears as hydrocarbon-filled porosity to conventional logs. In this study Total Organic Carbon and pyrolysis analyses were made on 93 core samples from four wells. Based on these data a new method was used to drive volumetric kerogen and free oil content, and kerogen was found to range up to 26 percent by volume. A good correlation was subsequently developed to derive kerogen from the uranium response of the spectral gamma ray log. Another important result of this study is the measurement of formation water salinity directly on core samples. Results on 50 measurements in the four study wells ranged from 19,000 to 220,000 ppm NaCl

Refining the Early Devonian time scale using Milankovitch cyclicity in Lochkovian–Pragian sediments (Prague Synform, Czech Republic)

Czech Academy of Sciences Publication Activity Database

da Silva, A.C.; Hladil, Jindřich; Chadimová, Leona; Slavík, Ladislav; Hilgen, F. J.; Bábek, O.; Dekkers, M. J.

2016-01-01

Roč. 455, 1 December (2016), s. 125-139 ISSN 0012-821X R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : orbital time scale * spectral analysis * Devonian * magnetic susceptibility * gamma ray spectrometry * limestone * Early Devonian * Lochkovian * Pragian * Emsian * Barrandian * peri-Gondwanan basins Subject RIV: DB - Geology ; Mineralogy Impact factor: 4.409, year: 2016

Devonian (Emsian-Eifelian) fish from the Lower Bokkeveld Group (Ceres Subgroup), South Africa

Science.gov (United States)

Anderson, M. E.; Almond, J. E.; Evans, F. J.; Long, J. A.

1999-07-01

Four major groups of fish are represented by fragmentary remains from South Africa's Lower Bokkeveld Group of Early to Middle Devonian age: the Acanthodii, Chondrichthyes, Placodermi and Osteichthyes. These represent the oldest known occurrences of these groups in southern Africa, as well as an important addition to the very meagre record of earlier Devonian fish from the Malvinokaffric Province of southwestern Gondwana. Bokkeveld fish material comes from the Gydo (Late Emsian) and Tra Tra (Middle Eifelian) Formations of the Western Cape and Eastern Cape Provinces. The cosmopolitan marine acanthodian Machæracanthus is represented only by isolated fin spines which may belong to two different species on the basis of their external ornamentation, cross-sectional outline and internal histology. The elasmobranchs are represented by four elements: (1) a flattened chondrocranium which bears affinity to the Late Devonian-Carboniferous symmoriid (protacrodont) 'cladodont' sharks. It is probably the earliest known (Emsian) shark chondrocranium; (2) an isolated, primitive scapulocoracoid with a very short coracoidal ridge; (3) ankylosed and isolated radials, interpreted as parts of pterygial plates of a paired fin of an unknown chondrichthyan bearing affinity to the Middle Devonian Zamponiopteron from Bolivia; and (4) isolated barlike structures, perhaps gill arch or a jaw elements, thought to be from the same taxon as (3). The placoderms are represented by an incomplete trunk armour and fragmentary, finely ornamented plates of a primitive antiarch. The Osteichthyes are represented by a single large scale of an unidentified dipnoan from the Eifelian of the Cedarberg range, as well as a probable sarcopterygian dermal plate from the Emsian of the Prince Albert area. These are among the earliest sarcopterygian remains recorded from the Malvinokaffric Province.

Thermal maturity of northern Appalachian Basin Devonian shales: Insights from sterane and terpane biomarkers

Science.gov (United States)

Hackley, Paul C.; Ryder, Robert T.; Trippi, Michael H.; Alimi, Hossein

2013-01-01

To better estimate thermal maturity of Devonian shales in the northern Appalachian Basin, eleven samples of Marcellus and Huron Shale were characterized via multiple analytical techniques. Vitrinite reflectance, Rock–Eval pyrolysis, gas chromatography (GC) of whole rock extracts, and GC–mass spectrometry (GCMS) of extract saturate fractions were evaluated on three transects that lie across previously documented regional thermal maturity isolines. Results from vitrinite reflectance suggest that most samples are immature with respect to hydrocarbon generation. However, bulk geochemical data and sterane and terpane biomarker ratios from GCMS suggest that almost all samples are in the oil window. This observation is consistent with the presence of thermogenic gas in the study area and higher vitrinite reflectance values recorded from overlying Pennsylvanian coals. These results suggest that vitrinite reflectance is a poor predictor of thermal maturity in early mature areas of Devonian shale, perhaps because reported measurements often include determinations of solid bitumen reflectance. Vitrinite reflectance interpretations in areas of early mature Devonian shale should be supplanted by evaluation of thermal maturity information from biomarker ratios and bulk geochemical data.

Geology of Paleozoic Rocks in the Upper Colorado River Basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, Excluding the San Juan Basin

Science.gov (United States)

Geldon, Arthur L.

2003-01-01

The geology of the Paleozoic rocks in the Upper Colorado River Basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, was studied as part of the U.S. Geological Survey's Regional Aquifer-System Analysis Program to provide support for hydrogeological interpretations. The study area is segmented by numerous uplifts and basins caused by folding and faulting that have recurred repeatedly from Precambrian to Cenozoic time. Paleozoic rocks in the study area are 0-18,000 feet thick. They are underlain by Precambrian igneous, metamorphic, and sedimentary rocks and are overlain in most of the area by Triassic formations composed mostly of shale. The overlying Mesozoic and Tertiary rocks are 0-27,000 feet thick. All Paleozoic systems except the Silurian are represented in the region. The Paleozoic rocks are divisible into 11 hydrogeologic units. The basal hydrogeologic unit consisting of Paleozoic rocks, the Flathead aquifer, predominantly is composed of Lower to Upper Cambrian sandstone and quartzite. The aquifer is 0-800 feet thick and is overlain gradationally to unconformably by formations of Cambrian to Mississippian age. The Gros Ventre confining unit consists of Middle to Upper Cambrian shale with subordinate carbonate rocks and sandstone. The confining unit is 0-1,100 feet thick and is overlain gradationally to unconformably by formations of Cambrian to Mississippian age. The Bighom aquifer consists of Middle Cambrian to Upper Ordovician limestone and dolomite with subordinate shale and sandstone. The aquifer is 0-3,000 feet thick and is overlain unconformably by Devonian and Mississipplan rocks. The Elbert-Parting confining unit consists of Lower Devonian to Lower Mississippian limestone, dolomite, sandstone, quartzite, shale, and anhydrite. It is 0-700 feet thick and is overlain conformably to unconformably by Upper Devonian and Mississippian rocks. The Madison aquifer consists of two zones of distinctly different lithology. The lower (Redwall-Leadville) zone

Traces in the dark: sedimentary processes and facies gradients in the upper shale member of the Upper Devonian-Lower Mississippian Bakken Formation, Williston Basin, North Dakota, U.S.A.

Science.gov (United States)

Egenhoff, Sven O.; Fishman, Neil S.

2013-01-01

Black, organic-rich rocks of the upper shale member of the Upper Devonian–Lower Mississippian Bakken Formation, a world-class petroleum source rock in the Williston Basin of the United States and Canada, contain a diverse suite of mudstone lithofacies that were deposited in distinct facies belts. The succession consists of three discrete facies associations (FAs). These comprise: 1) siliceous mudstones; 2) quartz- and carbonate-bearing, laminated mudstones; and 3) macrofossil-debris-bearing massive mudstones. These FAs were deposited in three facies belts that reflect proximal to distal relationships in this mudstone system. The macrofossil-debris-bearing massive mudstones (FA 3) occur in the proximal facies belt and contain erosion surfaces, some with overlying conodont and phosphate–lithoclast lag deposits, mudstones with abundant millimeter-scale siltstone laminae showing irregular lateral thickness changes, and shell debris. In the medial facies belt, quartz- and carbonate-bearing, laminated mudstones dominate, exhibiting sub-millimeter-thick siltstone layers with variable lateral thicknesses and localized mudstone ripples. In the distal siliceous mudstone facies belt, radiolarites, radiolarian-bearing mudstones, and quartz- and carbonate-bearing, laminated mudstones dominate. Overall, total organic carbon (TOC) contents range between about 3 and 10 wt %, with a general proximal to distal decrease in TOC content. Abundant evidence of bioturbation exists in all FAs, and the lithological and TOC variations are paralleled by changes in burrowing style and trace-fossil abundance. While two horizontal traces and two types of fecal strings are recognized in the proximal facies belt, only a single horizontal trace fossil and one type of fecal string characterize mudstones in the distal facies belt. Radiolarites intercalated into the most distal mudstones are devoid of traces and fecal strings. Bedload transport processes, likely caused by storm-induced turbidity

Ichnology applied to sequence stratigraphic analysis of Siluro-Devonian mud-dominated shelf deposits, Paraná Basin, Brazil

Science.gov (United States)

Sedorko, Daniel; Netto, Renata G.; Savrda, Charles E.

2018-04-01

Previous studies of the Paraná Supersequence (Furnas and Ponta Grossa formations) of the Paraná Basin in southern Brazil have yielded disparate sequence stratigraphic interpretations. An integrated sedimentological, paleontological, and ichnological model was created to establish a refined sequence stratigraphic framework for this succession, focusing on the Ponta Grossa Formation. Twenty-nine ichnotaxa are recognized in the Ponta Grossa Formation, recurring assemblages of which define five trace fossil suites that represent various expressions of the Skolithos, Glossifungites and Cruziana ichnofacies. Physical sedimentologic characteristics and associated softground ichnofacies provide the basis for recognizing seven facies that reflect a passive relationship to bathymetric gradients from shallow marine (shoreface) to offshore deposition. The vertical distribution of facies provides the basis for dividing the Ponta Grossa Formation into three major (3rd-order) depositional sequences- Siluro-Devonian and Devonian I and II-each containing a record of three to seven higher-order relative sea-level cycles. Major sequence boundaries, commonly coinciding with hiatuses recognized from previously published biostratigraphic data, are locally marked by firmground Glossifungites Ichnofacies associated with submarine erosion. Maximum transgressive horizons are prominently marked by unbioturbated or weakly bioturbated black shales. By integrating observations of the Ponta Grossa Formation with those recently made on the underlying marginal- to shallow-marine Furnas Formation, the entire Paraná Supersequence can be divided into four disconformity-bound sequences: a Lower Silurian (Llandovery-Wenlock) sequence, corresponding to lower and middle units of the Furnas; a Siluro-Devonian sequence (?Pridoli-Early Emsian), and Devonian sequences I (Late Emsian-Late Eifelian) and II (Late Eifelian-Early Givetian). Stratigraphic positions of sequence boundaries generally coincide with

Geochronology, stratigraphy and geochemistry of Cambro-Ordovician, Silurian and Devonian volcanic rocks of the Saxothuringian Zone in NE Bavaria (Germany)—new constraints for Gondwana break up and ocean-island magmatism

Science.gov (United States)

Höhn, Stefan; Koglin, Nikola; Klopf, Lisa; Schüssler, Ulrich; Tragelehn, Harald; Frimmel, Hartwig E.; Zeh, Armin; Brätz, Helene

2018-01-01

Stratigraphically well-defined volcanic rocks in Palaeozoic volcano-sedimentary units of the Frankenwald area (Saxothuringian Zone, Variscan Orogen) were sampled for geochemical characterisation and U-Pb zircon dating. The oldest rock suite comprises quartz keratophyre, brecciated keratophyre, quartz keratophyre tuff and basalt, formed in Upper Cambrian to Tremadocian time (c. 497-478 Ma). Basaltic volcanism continued until the Silurian. Quartz keratophyre shows post-collisional calc-alkaline signature, the Ordovician-Silurian basalt has alkaline signature typical of continental rift environments. The combined datasets provide evidence of Cambro-Ordovician bimodal volcanism and successive rifting until the Silurian. This evolution very likely resulted from break-up of the northern Gondwana margin, as recorded in many terranes throughout Europe. The position at the northern Gondwana margin is supported by detrital zircon grains in some tuffs, with typical Gondwana-derived age spectra mostly recording ages of 550-750 Ma and minor age populations of 950-1100 and 1700-2700 Ma. The absence of N-MORB basalt in the Frankenwald area points to a retarded break-off of the Saxothuringian terrane along a continental rift system from Uppermost Cambrian to Middle Silurian time. Geochemical data for a second suite of Upper Devonian basalt provide evidence of emplacement in a hot spot-related ocean-island setting south of the Rheic Ocean. Our results also require partial revision of the lithostratigraphy of the Frankenwald area. The basal volcanic unit of the Randschiefer Formation yielded a Tremadocian age and, therefore, should be attributed to the Vogtendorf Formation. Keratophyre of the Vogtendorf Formation, previously assigned to the Tremadoc, is most likely of Upper Devonian age.

Distribution and Thermal Maturity of Devonian Carbonate Reservoir Solid Bitumen in Desheng Area of Guizhong Depression, South China

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Yuguang Hou

2017-01-01

Full Text Available The distribution of solid bitumen in the Devonian carbonate reservoir from well Desheng 1, Guizhong Depression, was investigated by optical microscope and hydrocarbon inclusions analysis. Vb and chemical structure indexes measured by bitumen reflectance, laser Raman microprobe (LRM, and Fourier transform infrared spectroscopy (FTIR were carried out to determine the thermal maturity of solid bitumen. Based on the solid bitumen thermal maturity, the burial and thermal maturity history of Devonian carbonate reservoir were reconstructed by basin modeling. The results indicate that the fractures and fracture-related dissolution pores are the main storage space for the solid bitumen. The equivalent vitrinite reflectance of solid bitumen ranges from 3.42% to 4.43% converted by Vb (% and LRM. The infrared spectroscopy analysis suggests that there are no aliphatic chains detected in the solid bitumen which is rich in aromatics C=C chains (1431–1440 cm−1. The results of Vb (%, LRM, and FTIR analysis demonstrate that the solid bitumen has experienced high temperature and evolved to the residual carbonaceous stage. The thermal evolution of Devonian reservoirs had experienced four stages. The Devonian reservoirs reached the highest reservoir temperature 210–260°C during the second rapid burial-warming stage, which is the main period for the solid bitumen formation.

Unusual central Nevada geologic terranes produced by Late Devonian Antler orogeny and Alamo impact

Science.gov (United States)

Poole, Forrest G.; Sandberg, Charles

2015-01-01

This Special Paper is the product of nearly 25 years of geologic investigations. It is an exposition of two small areas, both less than 25 km east of the Mississippian Roberts Mountains allochthon, but each displaying a different, unique geologic terrane, previously undocumented in Nevada and perhaps in North America. One area, the Bisoni-McKay, at the south end of the Fish Creek Range, displays an olistostrome, shed eastward during the late Late Devonian (early Famennian) from a migrating Antler orogenic forebulge. The other, the Warm Springs–Milk Spring, at the south end of the Hot Creek Range, displays a deeper marine terrane affected by the early Late Devonian (middle Frasnian) Alamo impact.

Gas storage in the Upper Devonian-Lower Mississippian Woodford Shale, Arbuckle Mountains, Oklahoma: how much of a role do the cherts play?

Science.gov (United States)

Fishman, Neil S.; Ellis, Geoffrey S.; Paxton, Stanley T.; Abbott, Marvin M.; Boehlke, Adam

2010-01-01

How gas is stored in shale-gas systems is a critical element in characterizing these potentially prolific, low-porosity/permeability reservoirs. An integrated mineralogic, geochemical, and porosity/permeability study is of the Upper Devonian-Lower Mississippian Woodford Shale, Arbuckle Mountains, southern Oklahoma, at locations previously described through detailed stratigraphic and spectral gamma surveys, was undertaken to provide insights into possible mechanisms by which natural gas might be stored in Woodford reservoirs in the adjacent Anadarko Basin. The outcrops in the Arbuckle Mountains are an ideal location to study the Woodford because here the formation is immature or marginally mature for oil generation (Comer and Hinch, 1987; Lewan, 1987), so deep burial and thermal maturation are much less pronounced than is the case for the Woodford in the basin, and as such the samples we studied are not overprinted by possible alterations resulting from deep burial and heating. Rock types studied in the Woodford Shale are broadly divided into chert (n = 8) and mudstone (n = 10) lithologies that display different characteristics from the outcrop to thin section scales. Woodford cherts, based on quantitative X-ray diffraction (XRD), contain >85 weight (wt) % quartz, green algae). Quartz in mudstones is both detrital and authigenic, with unequivocal authigenic quartz occurring as monocrystalline “grains” that can partly or even completely infill Tasmanites; as in the case of the cherts, authigenic quartz in mudstones must have precipitated soon after deposition before significant burial and collapse of the soft, delicate Tasmanites cysts. MICP analyses (at 50% Hg saturation) reveal that, with one exception, mudstones have (1) porosities ranging from 1.97-6.31%, (2) low calculated permeabilities (0.011-0.089 D), and (3) small mean pore apertures (6.2-17.8 nm). Porosity in the mudstones occurs as (1) “slots” between clay mineral grains or plates, (2) micropores

The late Middle Devonian fauna of Red Hill I, Nevada, and its paleobiogeographic implications

Directory of Open Access Journals (Sweden)

H.-P. Schultze

2010-08-01

Full Text Available The fauna of the Middle Devonian Red Hill I locality, Nevada, is unusual in the co-occurrence of a rich fish assemblage with a rich invertebrate one. Sponges are second in abundance of specimens and number of species only to the fishes and occur together with other invertebrates (conodonts, conulariids, dacryoconarid tentaculites, gastropods, bivalves, brachiopods, arthropods, and unidentifiable ammonoids and echinoderms. The invertebrates indicate a marine depositional paleoenvironment. The conodonts indicate a placement within the lower disparalis Zone, late Givetian. The fish assemblage is dominated by the antiarch Asterolepis. All the other fishes, acanthodians, actinopterygians and sarcopterygians, are less common. The closest biogeographic relationship of the fish fauna is with the Middle/Late Devonian fish fauna of the Baltic Region, followed by that of eastern Canada (Miguasha, Scotland and Iran. This distribution corresponds to the Devonian Euramerica faunal province with connection to eastern Gondwana (Iran and Australia. Localities with the same genera as Red Hill I are interpreted as marine with the exception of the Scottish localities. Asterolepis is the most widely distributed vertebrate genus, mostly marine, but it may be able to enter freshwater like Eusthenopteron if one accepts a freshwater depositional paleoenvironment for the Scottish localities. doi:10.1002/mmng.201000001

Devonian sand injections and volcanism in the Murzuq Basin (south-west Libya)

DEFF Research Database (Denmark)

Moreau, Julien; Ghienne, Jean-Francois

system is original by its interaction with volcanism and its situation in an epicontinental intracratonic basin. The sand injections form a seal-bypass system between the Ordovician-Cambrian reservoirs and the Lower Devonian sandstones, breaching through the Silurian shale seal (and source rock...

Givetian (Middle Devonian) cladoxylopsid 'ferns' from Orkney, Northern Scotland

OpenAIRE

Berry, Christopher Mark; Hilton, Jason

2006-01-01

Two large fossil plants are described from the Givetian (Middle Devonian) Eday\\ud Flags, South Ronaldsay, Orkney Isles, northern Scotland. Fossils with branches joined to stems of\\ud this age are rare. Each specimen comprises a robust and tapering main trunk from which numerous\\ud closely spaced branches arise distally. Although poorly preserved such that generic identifications are\\ud not possible, both specimens display the characteristic architecture of the plant order Pseudosporochnales\\u...

How Reducing was the Late Devonian Ocean? The Role of Extensive Expansion of Anoxia in Marine Biogeochemical Cycles of Redox Sensitive Metals.

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Sahoo, S. K.; Jin, H.

2017-12-01

The evolution of Earth's biogeochemical cycles is intimately linked to the oxygenation of the oceans and atmosphere. The Late Devonian is no exception as its characterized with mass extinction and severe euxinia. Here we use concentrations of Molybdenum (Mo), Vanadium (V), Uranium (U) and Chromium (Cr) in organic rich black shales from the Lower Bakken Formation of the Williston Basin, to explore the relationship between extensive anoxia vs. euxinia and it's relation with massive release of oxygen in the ocean atmosphere system. XRF data from 4 core across the basin shows that modern ocean style Mo, U and Cr enrichments are observed throughout the Lower Bakken Formation, yet V is not enriched until later part of the formation. Given the coupling between redox-sensitive-trace element cycles and ocean redox, various models for Late Devonian ocean chemistry imply different effects on the biogeochemical cycling of major and trace nutrients. Here, we examine the differing redox behavior of molybdenum and vanadium under an extreme anoxia and relatively low extent of euxinia. The model suggests that Late Devonian was perhaps extensively anoxic- 40-50% compared to modern seafloor area, and a very little euxinia. Mo enrichments extend up to 500 p.p.m. throughout the section, representative of a modern reducing ocean. However, coeval low V enrichments only support towards anoxia, where anoxia is a source of V, and a sink for Mo. Our model suggests that the oceanic V reservoir is extremely sensitive to perturbations in the extent of anoxic condition, particularly during post glacial times.

Regressive transgressive cycle of Devonian sea in Uruguay verified by Palynology

International Nuclear Information System (INIS)

Da Silva, J.

1990-01-01

This work is about the results and conclusions of the populations palinomorphs study, carried out in Devonian formations in the center of Uruguay. The existence of a regressive transgressive cycle is verified by analyzing the vertical distribution of palinomorphs as well as is mentioned the presence of chintziest for the section studied - hoesphaeridium Cyathochitina kinds

Wangshangkia, a new Devonian ostracod genus from Dushan of Guizhou, South China

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Song, Junjun; Gong, Yiming

2018-02-01

Wangshangkia, a new genus of Ostracoda, from the Late Devonian in Dushan of Guizhou, South China, is described. This genus belongs to the family Bairdiocyprididae Shaver, 1961 and includes two new species, i.e. Wangshangkia dushaniensis and W. bailouiensis. The new genus is characterized by a wide ventral carina with radial striae. It is reported from the Famennian of South China and disappeared just below the Devonian-Carboniferous boundary. Wangshangkia is essentially a benthic crawler and is restricted to the shallow-marine depositional environment with a low hydrodynamic condition. Wangshangkia: urn:lsid:zoobank.org:act:34BF01D4-D202-492D-8E27-BC508EF7EFFB W. dushaniensis: urn:lsid:zoobank.org:act:D267C362-7510-4D19-996B-EA1848D7D025 W. bailouiensis: urn:lsid:zoobank.org:act:FE988AA0-7363-4D9E-A5AB-1526C8DBCDD9

From success to persistence: Identifying an evolutionary regime shift in the diverse Paleozoic aquatic arthropod group Eurypterida, driven by the Devonian biotic crisis.

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Lamsdell, James C; Selden, Paul A

2017-01-01

Mass extinctions have altered the trajectory of evolution a number of times over the Phanerozoic. During these periods of biotic upheaval a different selective regime appears to operate, although it is still unclear whether consistent survivorship rules apply across different extinction events. We compare variations in diversity and disparity across the evolutionary history of a major Paleozoic arthropod group, the Eurypterida. Using these data, we explore the group's transition from a successful, dynamic clade to a stagnant persistent lineage, pinpointing the Devonian as the period during which this evolutionary regime shift occurred. The late Devonian biotic crisis is potentially unique among the "Big Five" mass extinctions in exhibiting a drop in speciation rates rather than an increase in extinction. Our study reveals eurypterids show depressed speciation rates throughout the Devonian but no abnormal peaks in extinction. Loss of morphospace occupation is random across all Paleozoic extinction events; however, differential origination during the Devonian results in a migration and subsequent stagnation of occupied morphospace. This shift appears linked to an ecological transition from euryhaline taxa to freshwater species with low morphological diversity alongside a decrease in endemism. These results demonstrate the importance of the Devonian biotic crisis in reshaping Paleozoic ecosystems. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Development of a method to calculate organ doses for the upper gastrointestinal fluoroscopic examination

International Nuclear Information System (INIS)

Suleiman, O.H.

1989-01-01

A method was developed to quantitatively measure the upper gastrointestinal fluoroscopic examination in order to calculate organ doses. The dynamic examination was approximated with a set of discrete x-ray fields. Once the examination was segmented into discrete x-ray fields appropriate organ dose tables were generated using an existing computer program for organ dose calculations. This, along with knowledge of the radiation exposures associated with each of the fields, enabled the calculation of organ doses for the entire dynamic examination. The protocol involves videotaping the examination while fluoroscopic technique factors, tube current and tube potential, are simultaneously recorded on the audio tracks of the videotape. Subsequent analysis allows the dynamic examination to be segmented into a series of discrete x-ray fields uniquely defined by field size, projection, and anatomical region. The anatomical regions associated with the upper gastrointestinal examination were observed to be the upper, middle, and lower esophagus, the gastroesophageal junction, the stomach, and the duodenum

Dissection of Mammalian Organs and Opinions about It among Lower and Upper Secondary School Students

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Špernjak, Andreja; Šorgo, Andrej

2017-01-01

This article describes the results of a study that investigated the use of the dissection of organs in anatomy and physiology classes in Slovenian lower and upper secondary schools. Based on a sample of 485 questionnaires collected from Slovenian lower and upper secondary school students, we can conclude that dissection of mammalian organs during…

The silurian and devonian vertebrates of Bolivia

Directory of Open Access Journals (Sweden)

1986-01-01

formas de amplia repartición (Rhenanidos, algunos Acanthodios, Actinopterygios de tipo Moythomasia, formas con afinidades transpacíficas (Acanthodios próximos de Sinacanthus y formas tal vez endémicas (Pucapampella, Zamponiopteron. Silurian and Devonian vertebrate remains are described from various localities in Bolivia. Most of the material occurs in concretions in the marine Devonian of the Altiplano and Subandean area, and some isolated specimens have been found in sandstones and lutites. The jawless vertebrates are known only from isolated thelodont scales which occur in the Uppermost Silurian or Lower Devonian of Seripona, Chuquisaca. All the other vertebrate remains belong to gnathosthomes, in particular to the acanthodians, placoderms, chondrichthyans and actinopterygians. The acanthodians are represented by some ischnacanthid dentigerous jaw bones and climatiid spines and shoulder girdles. They are fairly abundant and show no marked differences from acanthodian remains known elsewhere in the Siluro-Devonian of Europe and North America. However, some isolated spines are suggestive of the genus Sinacanthus, known from the Lower Devonian of China The placoderms are represented only by the rhenanid Bolivosteus chacomensis Goujet et al, known from two well preserved braincases. This genus closely resembles Gemuendina (Lower Devonian of Germany with respect to the overall shape of the braincase, but its shoulder girdle differs substantially. The chondrichthyans are the most abundant vertebrates in the Devonian of Bolivia They are represented by isolated spines and endoskeletal elements lined with prismatic calcified cartilage Among them, some peculiar occipital regions of braincases are referred here to Pucapampella rodrigae n.g , n sp. These brain-cases differ from all other known Devonian chondrichthyan braincases in showing a ventrally continuous occipital fissure which completely separates the occiput from the rest of the brain-case. The strongly vaulted

An exceptionally preserved Late Devonian actinopterygian provides a new model for primitive cranial anatomy in ray-finned fishes

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Giles, Sam; Darras, Laurent; Clément, Gaël; Blieck, Alain; Friedman, Matt

2015-01-01

Actinopterygians (ray-finned fishes) are the most diverse living osteichthyan (bony vertebrate) group, with a rich fossil record. However, details of their earliest history during the middle Palaeozoic (Devonian) ‘Age of Fishes' remains sketchy. This stems from an uneven understanding of anatomy in early actinopterygians, with a few well-known species dominating perceptions of primitive conditions. Here we present an exceptionally preserved ray-finned fish from the Late Devonian (Middle Frasnian, ca 373 Ma) of Pas-de-Calais, northern France. This new genus is represented by a single, three-dimensionally preserved skull. CT scanning reveals the presence of an almost complete braincase along with near-fully articulated mandibular, hyoid and gill arches. The neurocranium differs from the coeval Mimipiscis in displaying a short aortic canal with a distinct posterior notch, long grooves for the lateral dorsal aortae, large vestibular fontanelles and a broad postorbital process. Identification of similar but previously unrecognized features in other Devonian actinopterygians suggests that aspects of braincase anatomy in Mimipiscis are apomorphic, questioning its ubiquity as stand-in for generalized actinopterygian conditions. However, the gill skeleton of the new form broadly corresponds to that of Mimipiscis, and adds to an emerging picture of primitive branchial architecture in crown gnathostomes. The new genus is recovered in a polytomy with Mimiidae and a subset of Devonian and stratigraphically younger actinopterygians, with no support found for a monophyletic grouping of Moythomasia with Mimiidae. PMID:26423841

On the origin of a phosphate enriched interval in the Chattanooga Shale (Upper Devonian) of Tennessee-A combined sedimentologic, petrographic, and geochemical study

Science.gov (United States)

Li, Yifan; Schieber, Juergen

2015-11-01

The Devonian Chattanooga Shale contains an uppermost black shale interval with dispersed phosphate nodules. This interval extends from Tennessee to correlative strata in Kentucky, Indiana, and Ohio and represents a significant period of marine phosphate fixation during the Late Devonian of North America. It overlies black shales that lack phosphate nodules but otherwise look very similar in outcrop. The purpose of this study is to examine what sets these two shales apart and what this difference tells us about the sedimentary history of the uppermost Chattanooga Shale. In thin section, the lower black shales (PBS) show pyrite enriched laminae and compositional banding. The overlying phosphatic black shales (PhBS) are characterized by phosbioclasts, have a general banded to homogenized texture with reworked layers, and show well defined horizons of phosphate nodules that are reworked and transported. In the PhBS, up to 8000 particles of P-debris per cm2 occur in reworked beds, whereas the background black shale shows between 37-88 particles per cm2. In the PBS, the shale matrix contains between 8-16 phosphatic particles per cm2. The shale matrix in the PhBS contains 5.6% inertinite, whereas just 1% inertinite occurs in the PBS. The shale matrix in both units is characterized by flat REE patterns (shale-normalized), whereas Phosbioclast-rich layers in the PhBS show high concentrations of REEs and enrichment of MREEs. Negative Ce-anomalies are common to all samples, but are best developed in association with Phosbioclasts. Redox-sensitive elements (Co, U, Mo) are more strongly enriched in the PBS when compared to the PhBS. Trace elements associated with organic matter (Cu, Zn, Cd, Ni) show an inverse trend of enrichment. Deposited atop a sequence boundary that separates the two shale units, the PhBS unit represents a transgressive systems tract and probably was deposited in shallower water than the underlying PBS interval. The higher phosphate content in the PhBS is

Sea-level changes vs. organic productivity as controls on Early and Middle Devonian bioevents: Facies- and gamma-ray based sequence-stratigraphic correlation of the Prague Basin, Czech Republic

Czech Academy of Sciences Publication Activity Database

Bábek, O.; Faměra, M.; Šimíček, D.; Weinerová, H.; Hladil, Jindřich; Kalvoda, J.

2018-01-01

Roč. 160, January (2018), s. 75-95 ISSN 0921-8181 R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : Devonian * carbonates * sequence stratigraphy * bioevents * eustatic cyclicity * palaeoclimatology Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 3.915, year: 2016

Discovery of the fossiliferous Cu Brei Formation (Lower Devonian) in the Kon Tum Block (South Viet Nam)

Science.gov (United States)

Thanh, Tong-Dzuy; Duyen, Than Duc; Hung, Nguyen Huu; My, Bui Phu

2007-01-01

Lower Devonian corals and stromatoporoids have recently been discovered in limestones among low grade metamorphic rocks on the western margin of the Kon Tum Block (South Viet Nam). This unit has been identified as the Cu Brei Formation. Coral and stromatoporoid species have been described including Squameofavosites aff. spongiosus, Parallelostroma cf. multicolumnum, Amphipora cf. rasilis, A. cf. raritalis, Simplexodictyon cf. artyschtense, Stromatopora cf. boriarchinovi and Stromatopora sp. indet. The Cu Brei Formation is exposed in a small area 6 km in length and 3 km wide at the foot of Cu Brei Mountain (Sa Thay District, Kon Tum Province). As this formation is in marine shelf facies it is probable that further exposures of Lower Devonian sediments may be discovered in the Kon Tum Block. This discovery raises the question of the tectonic history of the metamorphic Kon Tum Block. It is possible that the block was not an area of positive uplift from the beginning of Paleozoic as has been supposed, but was submerged in a marine environment, at least on its outer margins, in the Devonian, and possibly even earlier, in Early Paleozoic.

Sedimentology, conodonts and ostracods of the Devonian - Carboniferous strata of the Anseremme railway bridge section, Dinant Basin, Belgium

Science.gov (United States)

Casier, J.-G.; Mamet, B.; Preat, A.; Sandberg, C.A.

2004-01-01

Seven major carbonate microfacies are defined in the Devonian - Carboniferous (D/C) strata (50 m) of the Anseremme railway bridge section, south of Dinant. They permit recognition of several levels encompassing the Etroeungt and Hastie??re formations. "Bathymetric" sequences range from open marine, below the storm wave base, to semi-restricted lagoon. This sequence records a shallowing-upward trend of the relative sea level, from environments below the storm wave base to strongly eroded supraticial pre-evaporitic environments. Faunal components (echinoderms, brachiopods...) indicate open-marine domain for the first six microfacies located within the dysphoticeuphotic zone in relatively shallow waters. The textures of the rocks (mudstones to rudstones) associated with lamination characteristics indicate the position of the storm (SWB) and the fair-weather (FWWB) wave bases. Microfacies seven suggests a semi-restricted platform with salinity fluctuations from hypersaline brines to brackish waters. Thus, the boundary of the Etroeungt/Hastie??re formations is marked by an abrupt drop in sea level. Carbonate micro-conglomerates recording an important erosive phase and a sedimentary hiatus. The environment is again open marine in the upper part of the Hastie??re Formation. Our conclusion is that the Anseremme section is not a reliable continuous succession for the study of the D/C boundary. This confirms the VAN STEENWINKEL (1988, 1993 hypothesis based on other arguments. Conodont faunas demonstrate that the Devonian sequence spans the five youngest conodont zones, but that two of these zones are not represented. The Epinette Formation is dated as the youngest part of the Middle expansa Zone. Thus, the boundary with the Late praesulcata Zone probably coincides with the sharp sedimentological change at the base of the Etroeungt Formation, which is interpreted to belong entirely to this zone. The disconformably overlying basal bed 159 of the Hastie??re Formation is dated

U-Pb dating of silicic lavas, sills and syneruptive resedimented volcaniclastic deposits of the Lower Devonian Crudine Group, Hill End Trough, New South Wales

International Nuclear Information System (INIS)

Jagodzinski, E.A.; Black, L.P.

1999-01-01

The Hill End Trough of central-western New South Wales was an elongate deep marine basin that existed in the Lachlan Fold Belt from the early Late Silurian to late Early Devonian. It is represented by a regionally extensive. unfossiliferous sequence of interbedded turbidites and hemipelagites of substantially silicic Volcanic derivation, which passes laterally into contemporaneous shallow-water sedimentary rocks. The Turondale and Merrions Formations of the Lower Devonian Crudine Group are two prominent volcanogenic formations in the predominantly sedimentary trough sequence. They contain a range of primary and resedimented volcanic facies suitable for U-Pb dating. These include widespread subaqueous silicic lavas and/or lava cryptodomes. and thick sequences of crystal-rich volcaniclastic sandstone emplaced by a succession of muss-flows that were generated by interaction between contemporaneous subaerial pyroclastic flows and the sea. Ion microprobe dating of the two volcanogenic formations by means of the commonly used SL 13 zircon standard yields ages ranging between 411.3 ± 5.1 and 404.8 ± 4.8 Ma. Normalising the data against a different zircon standard (QGNG) yields preferred slightly older mean ages that range between 413.4 ± 6.6 and 407.1 ± 6.9 Ma. These ages broadly approximate the Early Devonian age that has been historically associated with the Crudine Group. However, the biostratigraphically inferred late Lochkovian - early Emsian (mid-Early Devonian) age for the Merrions Formation is inconsistent with the current Australian Phunerozoic Timescale, which assigns an age of 410 Ma to the Silurian-Devonian boundary, and ages of 404.5 Ma and 395.5 Ma to the base and top of the Pragian, respectively. There is, however, good agreement if the new ages are compared with the most recently published revision of the Devonian time-scale. This suggests that the Early Devonian stage boundaries of the Australian Phanerozoic Timescale need to be revised downward. The

Evolution of the Southern Margin of the Donbas (Ukraine) from Devonian to early Carboniferous Times.

NARCIS (Netherlands)

McCann, T.; Saintot, A.N.

2003-01-01

A Devonian-Early Carboniferous succession comprising thick clastic and carbonate sediments with interbedded volcanics was examined along the southern margin of the Donbas fold belt. Ukraine. Following initial rifting and subsidence, a continental (fluvial, lacustrine) succession was established.

PETRO- AND PALEOMAGNETIC STUDIES OF BASALTS OF THE UPPER DEVONIAN APPAINSKAYA SUITE (WESTERN YAKUTIA

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К. M. Konstantinov

2016-01-01

Full Text Available Introduction. One of the main tasks of paleomagnetic studies is to obtain a framework of reference poles for calculating the kinematic characteristics of lithospheric taxones as a basis for geodynamic reconstructions. Each paleomagnetic reference point must have a precise (±10 Ma geochronological dating and a maximum paleomagnetic reliability index. A correct paleomagnetic pole (PMP can be obtained from the data of geochronological and paleomagnetic studies conducted in one and the same geological object, such as a suite, an intrusive complex etc. In the Yakutian diamondiferous province (YDP, such objects include basalt nappes of the Upper Devonian Appainskaya suite, which stratigraphic position is undoubted (Fran, 385–375 Ma.Geological setting (in brief. In the eastern segments of the Siberian platform, a powerful cycle of tectonic and magmatic activity in the Middle Paleozoic produced transgressive and sheet intrusions, volcanic pipes, lava and tuff formations comprised of basites, as well as all the currently known industrial diamondiferous kimberlite bodies. Magmatic activity of basites was associated with formation of paleorift systems, including the largest one, Viluyi paleorift (Fig. 1. In the Middle Paleozoic, the geodynamic setting for magmatism and rifting was determined by the plume-lithosphere interaction. The rise of the plume’s matter underneath the thinned lithosphere was accompanied by decompression melting and formation of basaltic magmas in large volumes.We have studied basalts of the Appainskaya suite which were sampled from the Ygyatta and Markha river valleys (Fig. 2. In the coastal outcrops at the Ygyatta river, two nappes are observed, a (stratigraphically lower outcrop 17÷23/10 containing plagiophyre palagonite basalts (upper five meters are outcropped, and an upper outcrop 16/10 containing olivinophyric palagonite basalts (upper three meters are outcropped. In the coastal outcrops of the Markha river, from the

Late Devonian glacial deposits from the eastern United States signal an end of the mid-Paleozoic warm period

Science.gov (United States)

Brezinski, D.K.; Cecil, C.B.; Skema, V.W.; Stamm, R.

2008-01-01

A Late Devonian polymictic diamictite extends for more than 400??km from northeastern Pennsylvania across western Maryland and into east-central West Virginia. The matrix-supported, unbedded, locally sheared diamictite contains subangular to rounded clasts up to 2??m in diameter. The mostly rounded clasts are both locally derived and exotic; some exhibit striations, faceting, and polish. The diamictite commonly is overlain by laminated siltstone/mudstone facies associations (laminites). The laminites contain isolated clasts ranging in size from sand and pebbles to boulders, some of which are striated. The diamictite/laminite sequence is capped by massive, coarse-grained, pebbly sandstone that is trough cross-bedded. A stratigraphic change from red, calcic paleo-Vertisols in strata below the diamictite to non-calcic paleo-Spodosols and coal beds at and above the diamictite interval suggests that the climate became much wetter during deposition of the diamictite. The diamictite deposit is contemporaneous with regressive facies that reflect fluvial incision during the Late Devonian of the Appalachian basin. These deposits record a Late Devonian episode of climatic cooling so extreme that it produced glaciation in the Appalachian basin. Evidence for this episode of climatic cooling is preserved as the interpreted glacial deposits of diamictite, overlain by glaciolacustrine varves containing dropstones, and capped by sandstone interpreted as braided stream outwash. The Appalachian glacigenic deposits are contemporaneous with glacial deposits in South America, and suggest that Late Devonian climatic cooling was global. This period of dramatic global cooling may represent the end of the mid-Paleozoic warm interval that began in the Middle Silurian. ?? 2008 Elsevier B.V. All rights reserved.

Late Devonian spermatophyte diversity and paleoecology at Red Hill, north-central Pennsylvania, USA

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Cressler, Walter L. III. [Francis Harvey Green Library, 29 West Rosedale Avenue, West Chester University, West Chester, PA, 19383 (United States); Prestianni, Cyrille [Universite de Liege, Boulevard du Rectorat B18, Liege 4000 (Belgium); LePage, Ben A. [The Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, PA, 19103 and PECO Energy Company, 2301 Market Avenue, S9-1, Philadelphia, PA 19103 (United States)

2010-08-01

Early spermatophytes have been discovered at Red Hill, a Late Devonian (Famennian) fossil locality in north-central Pennsylvania, USA. The Red Hill locality contains an Archaeopteris-dominated flora within an outcrop of the Duncannon Member of the Catskill Formation. Palynological analyses of the plant fossil-bearing horizons within the Red Hill outcrop indicate deposition within the VCo palynozone. This is the earliest time horizon known to contain evidence for spermatophytes, and is contemporaneous with well-known spermatophyte-bearing deposits in West Virginia and Belgium. Some of the spermatophyte material from Red Hill compares well with Aglosperma sp., previously known as isolated ovules from the latest Devonian of South Wales and England, thus extending its geographic and stratigraphic range. Red Hill specimens of Aglosperma sp. occur both as isolated ovules and attached to dichotomously forking axes. Additional spermatophyte cupules discovered at Red Hill are morphologically similar to those of the previously described Late Devonian spermatophytes Elkinsia Rothwell, Scheckler, et Gillespie, Moresnetia Stockmans, and Xenotheca Arber et Goode. Some of the Red Hill cupule complexes are distinct from the aforementioned taxa in consisting of slender dichotomously forking axes terminating in paired cupules with highly fused and symmetric cupule quadrant lobes. The distinctive nature of these Red Hill specimens warrants the creation of Duodimidia pfefferkornii Cressler, Prestianni, et LePage gen. et sp. nov. Plant fossil remains with sphenopteroid foliage are also present at Red Hill, possibly attributable to the spermatophytes. Previous systematic sampling of the rich plant-fossil bearing layer at Red Hill and analysis of its floristic diversity and abundance as well as the presence and absence of charcoal suggests a pattern of floral turnover from a local-scale Rhacophyton-dominated community to spermatophyte colonization following disturbance by wildfires

Carbon and nitrogen isotopic analysis of coral-associated nitrogen in rugose corals of the Middle Devonian, implications for paleoecology and paleoceanography.

Science.gov (United States)

Hickey, A. N.; Junium, C. K.; Uveges, B. T.; Ivany, L. C.; Martindale, R. C.

2017-12-01

The Middle Devonian Appalachian Basin of Central New York hosts an extraordinary diversity of well-studied fossil invertebrates within the shallow marine sequences of the Givetian Age, Hamilton Group. Of particular interest are a series of aerially expansive coral beds with diverse assemblages of rugose corals. These well-preserved specimens provide an excellent opportunity to test the feasibility of δ15N and δ13C analyses in rugose corals in an effort to resolve outstanding issues regarding their paleoecology and ontogeny as well environmental dynamics within the Devonian Appalachian Basin. Here we present carbon and nitrogen isotope analyses of the rugose corals Heliophyllum and Siphonophrentis from the Joshua Coral Bed. Corals were cleaned of the host calcareous shale and sonicated sequentially in deionized water and methanol, and then oxidatively cleaned. Cleaned corals were sectioned into 0.5cm billets to obtain enough residual organic material for analysis. The organic content of the corals is low, but nanoEA allows for serial sampling of 5-10 samples per coral. Coral sections were decarbonated and the residual organic material is filtered and dried prior to analysis. Coral organic matter is analyzed in triplicate using nanoEA, which is a cryo-trapping, capillary focusing technique for δ15N and δ13C. The δ15N of organic matter extracted from rugose corals is, on average, enriched by 2-4‰ relative to the bulk nitrogen in the host rock. As well, the δ13C of organic carbon from the corals is 13C-enriched relative to the bulk rock, but to a lesser degree (no more than 1.5‰). Assuming that the bulk rock carbon and nitrogen are largely representative of the long-term primary production background, the modest enrichment is consistent with a trophic effect, and that rugose corals are likely planktivores. In an individual coral, δ15N ranges by 3-4‰ over its length, and when adjusted for trophic enrichment varies around the average δ15N of bulk

Devonian and Lower Carboniferous Conodonts of the Cantabrian Mountains (Spain) and their stratigraphic application

NARCIS (Netherlands)

Adrichem Boogaert, van H.A.

1967-01-01

A short review of the literature on the stratigraphy of the Devonian and the Lower Carboniferous of the Cantabrian Mountains precedes the report of the author's stratigraphic and palaeontologic observations in León: the Río Esla area (Gedinnian to Viséan), the central Cantabrian area (Famennian to

Rugose corals across the Devonian-Carboniferous boundary in NW Turkey

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Julien Denayer

2016-02-01

Full Text Available An uppermost Famennian (Strunian coral assemblage has been recovered in the middle part of the Yılanlı Formation of the Istanbul Zone (Zonguldak and Bartın areas, NW Turkey. In the Bartın area, the studied fossiliferous interval corresponds to a c. 30 m-thick unit of bioclastic to peloidal wackestone to packstone grading to grainstone and including two stromatoporoid biostromes. In the Zonguldak area, 60 km westward, the bioclastic facies is dominant. The rugose corals are mainly solitary taxa belonging to the genera Campophyllum, Bounophyllum, Amplexocarinia, and ?Metriophyllum, and only one colonial genus occurs: Pseudoendophyllum. This fauna is similar to that documented in Europe. The campophyllids and dibunophyllids are the main component of the uppermost Famennian assemblages in S Belgium, N France, W Germany, NW and S Poland. The endophyllids occur in S Poland, Novaya Zemlya, and in the Ural Mountains. The Istanbul Zone is supposed to be situated in the central part of the Palaeotethys Ocean, along the southern margin of Laurussia during the uppermost Devonian and Carboniferous. The rugose corals indicate some relationship with the eastern part of Laurussia, or that both areas were under a common marine influence at this time. The global Hangenberg event was not recognized in the Turkish localities, except for the disappearance of the corals, occurring less than 19 m below the Devonian–Carboniferous boundary based on the foraminifers. There is no major facies change through the boundary and the first Carboniferous corals (small Uralinia and Caninophyllum appear 6 m above the D–C boundary. The new species Caninophyllum charli sp. nov. is described from the upper part of the lower Tournaisian.

The Lower Devonian of Ouled Abbou (Morocco. Sedimentary organization; diagenetic modes and impact on porosity

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Razouani, A.

2007-12-01

Full Text Available The region of Ouled Abbou is characterized by the intercalation of carbonated beds in Silurian-Devonian pelite-sandstones. The series is organized into a succesion of three deposition sequences: SD1, SD2, SD3 of Silurian-Lochkovian, Praguian and Emsian age, respectively, developed in a monoclynal platform-type ramp. The hydrodynamics, in relation to variations in sea level, controlled the formation and distribution of the carbonated facies (bioclastic deposits, slope deposits, etc.. In the carbonate beds, diagenetic analysis reveals the sequence of development of the diagenetic transformations: It is essentially the result of multiple phases of cementing and recrystallization, mainly affecting the granular facies that define the diagenetic history leading to an almost complete lithification, hence their low potential as a possible reservoir. Early dolomitisation appears at the summit of sequences SD2 and SD3, leading to the formation of a crystalline rock (dolomicrosparite followed by a remplacement-recristallisation of calcareous mud. These transformations are later affected by compaction, cracking and tectonic phases of late dolomitisation.La región de Ouled Abbou se caracteriza por la intercalación de niveles carbonatados en pelitas silurico-devónicas. Esta serie está estructurada en una secuencia de tres niveles de depósitos: SD1, SD2, SD3, que son respectivamente de edad siluro-lochkoviense, praguiense y emsiense, desarrollados en una plataforma mixta de typo rampa monoclinal. La hidrodinámica, en relación con las variaciones del nivel del mar, controló la formación y distribución de las facies carbonatadas (depósitos bioclásticos, de pendiente, etc.. El análisis de los niveles carbonatados ha permitido establecer la secuencia de desarrollo de las tranformaciones diagenéticas. Éstas son esencialmente el resultado de múltiples fases de cementación y recristalización, que afectan principalmente a las facies granulares. La

Ichnologic Note. Evidence of Predation on the Rugose Coral Calceola Sandalina (Devonian, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Galle, Arnošt; Mikuláš, Radek

2003-01-01

Roč. 10, - (2003), s. 37-41 ISSN 1042-0940 R&D Projects: GA AV ČR IAA3013207 Institutional research plan: CEZ:AV0Z3013912 Keywords : corals * Calceola * Devonian Subject RIV: DB - Geology ; Mineralogy http://rzblx1.uni-regensburg.de/ezeit/detail.phtml?bibid=CASCR&colors=7&lang=en&jour_id=41560

Marcellus shale gas potential in the southern tier of New York

Energy Technology Data Exchange (ETDEWEB)

Faraj, B. [Talisman Energy Inc., Calgary, AB (Canada); Duggan, J. [Hunt Oil Canada, Calgary, AB (Canada)

2008-07-01

Marcellus shale is a significant, underexplored, shale gas target in the Appalachian Basin. Gas-in-place estimates in the Marcellus shale range from 200 to 100 billion cubic feet (bcf). The Devonian shales have favorable attributes such as high total organic content (TOC), high gas content, favorable mineralogy and over-pressured. Land owned by Fortuna Energy in the northern Appalachian Basin may contain significant shale gas with unrisked gas-in-place in excess of 10 trillion cubic feet. Unlocking the true shale gas potential requires innovative drilling and completion techniques. This presentation discussed Marcellus shale gas potential in the southern tier and a test program being conducted by Fortuna to test the potential. Several photographs were shown, including Taughannock Falls, Finger Lakes and the Ithaca Shale, Sherburne Sandstone, and Geneseo Shale; two orthogonal fracture sets in the Upper Devonian Geneseo Shale; and two orthogonal fracture sets in the Upper Devonian Rocks, near Corning, New York. Figures that were presented included the supercontinent Pangaea in the early Triassic; undiscovered gas resources in the Appalachian Basin; stratigraphy; and total gas production in New York since 1998. Fortuna's work is ongoing in the northern Appalachian Basin. tabs., figs.

Acoustic observation of living organisms reveals the upper limit of the oxygen minimum zone.

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Arnaud Bertrand

Full Text Available BACKGROUND: Oxygen minimum zones (OMZs are expanding in the World Ocean as a result of climate change and direct anthropogenic influence. OMZ expansion greatly affects biogeochemical processes and marine life, especially by constraining the vertical habitat of most marine organisms. Currently, monitoring the variability of the upper limit of the OMZs relies on time intensive sampling protocols, causing poor spatial resolution. METHODOLOGY/PRINCIPAL FINDINGS: Using routine underwater acoustic observations of the vertical distribution of marine organisms, we propose a new method that allows determination of the upper limit of the OMZ with a high precision. Applied in the eastern South-Pacific, this original sampling technique provides high-resolution information on the depth of the upper OMZ allowing documentation of mesoscale and submesoscale features (e.g., eddies and filaments that structure the upper ocean and the marine ecosystems. We also use this information to estimate the habitable volume for the world's most exploited fish, the Peruvian anchovy (Engraulis ringens. CONCLUSIONS/SIGNIFICANCE: This opportunistic method could be implemented on any vessel geared with multi-frequency echosounders to perform comprehensive high-resolution monitoring of the upper limit of the OMZ. Our approach is a novel way of studying the impact of physical processes on marine life and extracting valid information about the pelagic habitat and its spatial structure, a crucial aspect of Ecosystem-based Fisheries Management in the current context of climate change.

Reevaluation of the Piermont-Frontenac allochthon in the Upper Connecticut Valley: Restoration of a coherent Boundary Mountains–Bronson Hill stratigraphic sequence

Science.gov (United States)

Rankin, Douglas W.; Tucker, Robert D.; Amelin, Yuri

2013-01-01

The regional extent and mode and time of emplacement of the Piermont-Frontenac allochthon in the Boundary Mountains–Bronson Hill anticlinorium of the Upper Connecticut Valley, New Hampshire–Vermont, are controversial. Moench and coworkers beginning in the 1980s proposed that much of the autochthonous pre–Middle Ordovician section of the anticlinorium was a large allochthon of Silurian to Early Devonian rocks correlated to those near Rangeley, Maine. This ∼200-km-long allochthon was postulated to have been transported westward in the latest Silurian to Early Devonian as a soft-sediment gravity slide on a hypothesized Foster Hill fault. New mapping and U-Pb geochronology do not support this interpretation. The undisputed Rangeley sequence in the Bean Brook slice is different from the disputed sequence in the proposed larger Piermont-Frontenac allochthon, and field evidence for the Foster Hill fault is lacking. At the type locality on Foster Hill, the postulated “fault” is a stratigraphic contact within the Ordovician Ammonoosuc Volcanics. The proposed Foster Hill fault would place the Piermont-Frontenac allochthon over the inverted limb of the Cornish(?) nappe, which includes the Emsian Littleton Formation, thus limiting the alleged submarine slide to post-Emsian time. Mafic dikes of the 419 Ma Comerford Intrusive Complex intrude previously folded strata attributed to the larger Piermont-Frontenac allochthon as well as the autochthonous Albee Formation and Ammonoosuc Volcanics. The Lost Nation pluton intruded and produced hornfels in previously deformed Albee strata. Zircons from an apophysis of the pluton in the hornfels have a thermal ionization mass spectrometry 207Pb/206Pb age of 444.1 ± 2.1 Ma. Tonalite near Bath, New Hampshire, has a zircon sensitive high-resolution ion microprobe 206Pb/238U age of 492.5 ± 7.8 Ma. The tonalite intrudes the Albee Formation, formerly interpreted as the Silurian Perry Mountain Formation of the proposed allochthon

Conodont-bearing formations of Devonian and Lower Carboniferous age in northern León and Palencia (Spain)

NARCIS (Netherlands)

Adrichem Boogaert, van H.A.

1965-01-01

Conodonts have been extracted from calcareous units of the Devonian and Lower Carboniferous sequence from 3 areas in the S. part of the Cantabrian Mountains. There can be distinguished Emsian, Givetian, Frasnian, Famennian and Viséan faunas.

A Large Trace Fossil in Nodular Limestones (Lower Devonian, Czech Republic): Sedimentological Consequences, Ethology and Taphonomy

Czech Academy of Sciences Publication Activity Database

Mikuláš, Radek; Hladil, Jindřich

2015-01-01

Roč. 22, č. 2 (2015), s. 69-76 ISSN 1042-0940 R&D Projects: GA ČR GA14-18183S Institutional support: RVO:67985831 Keywords : bioturbation * Fodinichnia * carbonate * nodules * Devonian * Czech Republic Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.935, year: 2015

Systematics of some Lower and Middle Devonian spiriferid brachiopods from Gaspe with a revision of the superfamily Delthyridoidea

DEFF Research Database (Denmark)

Bizzarro, Martin; Lespérance, P.J.

1999-01-01

new species aye described: Howellella (Howellella) forillonensis, Brachyspirifer (Brachyspirifer) briseboisi, Paraspirifer desbiensi, Brevispirifer florentinus, and B. quebecensis, The occurrence of Brevispirifer species with Middle Devonian chonetaceans confirms the presence of marine Eifelian strata...

Successful Recovery and Transplantation of 11 Organs Including Face, Bilateral Upper Extremities, and Thoracic and Abdominal Organs From a Single Deceased Organ Donor.

Science.gov (United States)

Tullius, Stefan G; Pomahac, Bohdan; Kim, Heung Bae; Carty, Matthew J; Talbot, Simon G; Nelson, Helen M; Delmonico, Francis L

2016-10-01

We report on the to date largest recovery of 11 organs from a single deceased donor with the transplantation of face, bilateral upper extremities, heart, 1 lung, liver (split for 2 recipients), kidneys, pancreas, and intestine. Although logistically challenging, this case demonstrates the feasibility and safety of the recovery of multiple thoracic and abdominal organs with multiple vascular composite allotransplants and tissues. Our experience of 8 additional successful multiple vascular composite allotransplants, thoracic, and abdominal organ recoveries suggests that such procedures are readily accomplishable from the same deceased donor.

Early Devonian polygnathids of Northeast Asia and correlation of Pragian/Emsian strata of the marginal seas of Angarida

Czech Academy of Sciences Publication Activity Database

Baranov, V.; Slavík, Ladislav; Blodgett, R. B.

2014-01-01

Roč. 89, č. 3 (2014), s. 645-678 ISSN 1214-1119 Institutional support: RVO:67985831 Keywords : Early Devonian * Pragian/Emsian strata * Angarida Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.515, year: 2014

Correlation of Early Devonian (Lochkovian-early Pragian) conodont faunas of the South Urals (Russia)

Czech Academy of Sciences Publication Activity Database

Mavrinskaya, T.; Slavík, Ladislav

2013-01-01

Roč. 88, č. 3 (2013), s. 283-296 ISSN 1214-1119 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100131201 Institutional support: RVO:67985831 Keywords : South Urals, West Zilair Zone, Lower Devonian, global conodont correlation, Lochkovian, Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.495, year: 2013

Devonian trilobites of the southern Cantabrian Mountains (northern Spain) with a systematic description of the Asteropyginae

NARCIS (Netherlands)

Smeenk, Z.

1983-01-01

This paper shows the results of a research into the Devonian trilobites of the southern Cantabrian Mountains. The systematics of the most common group, the subfamily of the Asteropyginae, forms the major part of this work. More than 50 species, belonging to sixteen (sub)genera are distinguished;

Concentration mechanisms of uranium in the mineralized fractures of the Lower Devonian of the Belgian Ardennes - The case of the Oizy area

International Nuclear Information System (INIS)

Charlet, J.M.; Doremus, P.; Quinif, Y.

1987-01-01

During a reconnaissance survey for uranium in the Belgian Paleozoic several anomalies or U occurrences have been discovered in the Lower Devonian by a car-borne radiometric survey. These anomalies appear in relation with mobilization and reconcentration processes at the boundary of redox fronts or following alteration fronts in the detrital series of the Lower Devonian. This paper describes the Oizy anomaly which occurs in a fracturated zone of the Gedinnian formations of the Ardenne Anticline and puts it back in the general context of the U concentrations of the Lower Devonian of the Belgian Ardennes. After a lithostratigraphic, structural and radiometric study of the quarry where the U concentrations occur, a laboratory study of the surrounding rocks has been performed by various techniques (γ- and α-spectrometry, X-ray diffraction, autoradiography and low-level counting technique, analytical chemistry). One can conclude that the mineralized fractures of Oizy are due to a downward remobilization of U by subsurface processes during post-Hercynian periods. 26 refs.; 11 figs.; 1 plate; 2 tabs

PALEOMAGNETISM OF SILURIAN AND DEVONIAN VOLCANICS FROM THE CHINGIZ ISLAND ARC, KAZAKHSTAN, AND ITS BEARING ON TECTONIC EVOLUTION OF THE URAL-MONGOL BELT

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Natalia M. Levashova

2011-01-01

Full Text Available The tectonic and paleogeographic evolution of the Ural-Mongol belt between the cratons of Baltica, Siberia, and Tarim is the key to the formation of the Eurasian supercontinent during Paleozoic time, but the views on this complicated process remain very disparate and sometimes controversial. Three volcanic formations of the Middle Silurian, LowertoMiddle Devonian and Middle Devonian age from the southwestern boundary of the Chingiz Range (NE Kazakhstan yields what are interpreted as primary paleomagnetic directions that help clarify the evolution of the belt. A singlepolarity characteristic component in midSilurian andesites yields a positive intraformational conglomerate test, whereas dualpolarity prefolding components are isolated from the two Devonian collections. These new data were evaluated together with previously published paleomagnetic results from Paleozoic rocks in the Chingiz Range, and allow us to establish with confidence the hemisphere in which the area was located at a given time. We conclude that NE Kazakhstan was steadily moving northward crossing the equator in Silurian time. These new paleomagnetic data from the Chingiz range also agree with and reinforce the hypothesis that the strongly curved volcanic belts of Kazakhstan underwent oroclinal bending between Middle Devonian and Late Carboniferous time. A comparison of the Chingiz paleolatitudes with those of Siberia shows similarities between the northward motion and rotational history of the Chingiz unit and those of Siberia, which imposes important constraints on the evolving paleogeography of the Ural-Mongol belt.

Spectroscopic Studies on Organic Matter from Triassic Reptile Bones, Upper Silesia, Poland

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Surmik, Dawid; Boczarowski, Andrzej; Balin, Katarzyna; Dulski, Mateusz; Szade, Jacek; Kremer, Barbara; Pawlicki, Roman

2016-01-01

Fossil biomolecules from an endogenous source were previously identified in Cretaceous to Pleistocene fossilized bones, the evidence coming from molecular analyses. These findings, however, were called into question and an alternative hypothesis of the invasion of the bone by bacterial biofilm was proposed. Herewith we report a new finding of morphologically preserved blood-vessel-like structures enclosing organic molecules preserved in iron-oxide-mineralized vessel walls from the cortical region of nothosaurid and tanystropheid (aquatic and terrestrial diapsid reptiles) bones. These findings are from the Early/Middle Triassic boundary (Upper Roetian/Lowermost Muschelkalk) strata of Upper Silesia, Poland. Multiple spectroscopic analyses (FTIR, ToF-SIMS, and XPS) of the extracted "blood vessels" showed the presence of organic compounds, including fragments of various amino acids such as hydroxyproline and hydroxylysine as well as amides, that may suggest the presence of collagen protein residues. Because these amino acids are absent from most proteins other than collagen, we infer that the proteinaceous molecules may originate from endogenous collagen. The preservation of molecular signals of proteins within the "blood vessels" was most likely made possible through the process of early diagenetic iron oxide mineralization. This discovery provides the oldest evidence of in situ preservation of complex organic molecules in vertebrate remains in a marine environment. PMID:26977600

Spectroscopic Studies on Organic Matter from Triassic Reptile Bones, Upper Silesia, Poland.

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Dawid Surmik

Full Text Available Fossil biomolecules from an endogenous source were previously identified in Cretaceous to Pleistocene fossilized bones, the evidence coming from molecular analyses. These findings, however, were called into question and an alternative hypothesis of the invasion of the bone by bacterial biofilm was proposed. Herewith we report a new finding of morphologically preserved blood-vessel-like structures enclosing organic molecules preserved in iron-oxide-mineralized vessel walls from the cortical region of nothosaurid and tanystropheid (aquatic and terrestrial diapsid reptiles bones. These findings are from the Early/Middle Triassic boundary (Upper Roetian/Lowermost Muschelkalk strata of Upper Silesia, Poland. Multiple spectroscopic analyses (FTIR, ToF-SIMS, and XPS of the extracted "blood vessels" showed the presence of organic compounds, including fragments of various amino acids such as hydroxyproline and hydroxylysine as well as amides, that may suggest the presence of collagen protein residues. Because these amino acids are absent from most proteins other than collagen, we infer that the proteinaceous molecules may originate from endogenous collagen. The preservation of molecular signals of proteins within the "blood vessels" was most likely made possible through the process of early diagenetic iron oxide mineralization. This discovery provides the oldest evidence of in situ preservation of complex organic molecules in vertebrate remains in a marine environment.

Devonian post-orogenic extension-related volcano-sedimentary rocks in the northern margin of the Tibetan Plateau, NW China: Implications for the Paleozoic tectonic transition in the North Qaidam Orogen

Science.gov (United States)

Qin, Yu; Feng, Qiao; Chen, Gang; Chen, Yan; Zou, Kaizhen; Liu, Qian; Jiao, Qianqian; Zhou, Dingwu; Pan, Lihui; Gao, Jindong

2018-05-01

The Maoniushan Formation in the northern part of the North Qaidam Orogen (NQO), NW China, contains key information on a Paleozoic change in tectonic setting of the NQO from compression to extension. Here, new zircon U-Pb, petrological, and sedimentological data for the lower molasse sequence of the Maoniushan Formation are used to constrain the timing of this tectonic transition. Detrital zircons yield U-Pb ages of 3.3-0.4 Ga with major populations at 0.53-0.4, 1.0-0.56, 2.5-1.0, and 3.3-2.5 Ga. The maximum depositional age of the Maoniushan Formation is well constrained by a youngest detrital zircon age of ∼409 Ma. Comparing these dates with geochronological data for the region indicates that Proterozoic-Paleozoic zircons were derived mainly from the NQO as well as the Oulongbuluk and Qaidam blocks, whereas Archean zircons were probably derived from the Oulongbuluk Block and the Tarim Craton. The ∼924, ∼463, and ∼439 Ma tectonothermal events recorded in this region indicate that the NQO was involved in the early Neoproterozoic assembly of Rodinia and early Paleozoic microcontinental convergence. A regional angular unconformity between Devonian and pre-Devonian strata within the NQO suggests a period of strong mountain building between the Oulongbuluk and Qaidam blocks during the Silurian, whereas an Early Devonian post-orogenic molasse, evidence of extensional collapse, and Middle to Late Devonian bimodal volcanic rocks and Carboniferous marine carbonate rocks clearly reflect long-lived tectonic extension. Based on these results and the regional geology, we suggest that the Devonian volcano-sedimentary rocks within the NQO were formed in a post-orogenic extensional setting similar to that of the East Kunlun Orogen, indicating that a major tectonic transition from compression to extension in these two orogens probably commenced in the Early Devonian.

Petrological, geochemical, isotopic, and geochronological constraints for the Late Devonian-Early Carboniferous magmatism in SW Gondwana (27-32°LS): an example of geodynamic switching

Science.gov (United States)

Dahlquist, Juan A.; Alasino, Pablo H.; Basei, Miguel A. S.; Morales Cámera, Matías M.; Macchioli Grande, Marcos; da Costa Campos Neto, Mario

2018-04-01

We report a study integrating 13 new U-Pb LA-MC-ICP-MS zircon ages and Hf-isotope data from dated magmatic zircons together with complete petrological and whole-rock geochemistry data for the dated granitic rocks. Sample selection was strongly based on knowledge reported in previous investigations. Latest Devonian-Early Carboniferous granite samples were collected along a transect of 900 km, from the inner continental region (present-day Eastern Sierras Pampeanas) to the magmatic arc (now Western Sierras Pampeanas and Frontal Cordillera). Based on these data together with ca. 100 published whole-rock geochemical analyses we conclude that Late Devonian-Early Carboniferous magmatism at this latitude represents continuous activity (ranging from 322 to 379 Ma) on the pre-Andean margin of SW Gondwana, although important whole-rock and isotopic compositional variations occurred through time and space. Combined whole-rock chemistry and isotope data reveal that peraluminous A-type magmatism started in the intracontinental region during the Late Devonian, with subsequent development of synchronous Carboniferous peraluminous and metaluminous A-type magmatism in the retro-arc region and calc-alkaline magmatism in the western paleomargin. We envisage that magmatic evolution was mainly controlled by episodic fluctuations in the angle of subduction of the oceanic plate (between flat-slab and normal subduction), supporting a geodynamic switching model. Subduction fluctuations were relatively fast (ca. 7 Ma) during the Late Devonian and Early Carboniferous, and the complete magmatic switch-off and switch-on process lasted for 57 Ma. Hf T DM values of zircon (igneous and inherited) from some Carboniferous peraluminous A-type granites in the retro-arc suggest that Gondwana continental lithosphere formed during previous orogenies was partly the source of the Devonian-Carboniferous granitic magmas, thus precluding the generation of the parental magmas from exotic terranes.

U-Pb SHRIMP ages of volcanic zircons from the Merrions and Turondale Formations, New South Wales, and the early devonian time-scale: a biostratigraphic and sedimentological assessment

International Nuclear Information System (INIS)

Packham, G.H.

2003-01-01

U-Pb ages for volcanic zircons from the Lower Devonian Turondale and Merrions Formations initially dated by Jagodzinski and Black (1999) have been recalculated by Compston (2000, 2001). The Turondale, Waterbeach and Merrions Formations are, in ascending stratigraphic order, three of the Lower Devonian deep-water formations of the Hill End Trough. The recent discovery of a Lochkovian conodont fauna of the delta zone in derived limestone blocks from the uppermost beds of the Turondale Formation has established a maximum age for that horizon. The principal lithological assemblages of the formations are volcanic (megaturbidite and lavas), epiclastic turbidites and essentially hemipelagic lithologies. The mean zircon ages, determined by Sensitive High-Resolution Ion MicroProbe (SHRIMP), suggest a long duration for the Merrions Formation, 615 m thick and 91% volcanic, and a very much shorter interval for the upper two-thirds of the Turondale Formation, 360 m thick and 34% volcanic, plus the intervening non-volcanic Waterbeach Formation, 512 m thick. A sedimentological model based on scaled depositional rates for the facies has been used to estimate the relative accumulation rates and durations of the succession from the base of the Turondale Formation to the top of the Merrions Formation The model indicates that the Merrions Formation accumulated in a much shorter time than the interval from the top of the lower Turondale Formation to the base of the Merrions Formation. The analytical uncertainties of the Jagodzinski and Black (1999) zircon ages are large enough to be compatible with the sedimentological model, but the smaller analytical uncertainties calculated by Compston (2000, 2001) fall far from the scaled sedimentological model. Grouping together of the lower Merrions Formation and lower Turondale Formation zircon dates in Compston (2000) for a single mid-Lochkovian age is in conflict with the biostratigraphic and sedimentological evidence available and the derived

The Frasnian-Famennian boundary (Upper Devonian) within the Hanover-Dunkirk transition, northern Appalachian basin, western New York state

Energy Technology Data Exchange (ETDEWEB)

Over, D.J. (State Univ. of New York, Geneseo, NY (United States))

1993-03-01

In western New York State interbedded pyritic silty green and dark grey shales and siltstone of the Hanover Member, Java Formation, West Falls Group, are overlain by thick pyritic dark grey-black shale of the Dunkirk Member of the Canadaway formation. The dark shales in the upper Hanover and Dunkirk contain a diverse and well preserved conodont fauna which allows precise placement of the Frasnian-Famennian boundary at several described sections. At Pt. Gratiot, in far western New York State, the contact between the Hanover and Dunkirk is disconformable. The Frasnian-Famennian boundary is marked by a pyritic lag deposit at the base of the Dunkirk which contains Palmatolepis triangularis and Pa. subperlobata. The underlying upper Hanover is characterized by Pa. bogartensis , Pa. cf. Pa. rhenana, Pa. winchelli, and Ancyrognathus (asymmetricus/calvini) Eastward, in the direction of the paleo-source area, the Frasnian-Famennian boundary is within the upper Hanover Member. At Irish Gulf the boundary is recognized within a 10 cm thick laminated pyritic dark grey shale bed 3.0 m below the base of the Dunkirk. Palmatolepis triangularis and Pa. subperlobata occur below a conodont-rich lag layer in the upper 2 cm of the bed. Palmatolepis bogartensis , Pa. cf. Pa. rhenana, Ancyrodella curvata, and Icriodus alternatus occur in the underlying 8 cm. Palmatolepis triangularis and Pa. winchelli occur in an underlying dark shale bed separated from the boundary bed by a hummocky cross-bedded siltstone layer.

U-Pb zircon geochronology of Late Devonian to Early Carboniferous extension-related silicic volcanism in the northern New England Fold Belt

International Nuclear Information System (INIS)

Bryan, S.E.; Holcombe, R.J.; Fielding, C.R.; Allen, C.M.

2004-01-01

Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis of zircons confirm a Late Devonian to Early Carboniferous age (ca 360-350 Ma) for silicic volcanic rocks of the Campwyn Volcanics and Yarrol terrane of the northern New England Fold Belt (Queensland). These rocks are coeval with silicic volcanism recorded elsewhere in the fold belt at this time (Connors Arch, Drummond Basin). The new U-Pb zircon ages, in combination with those from previous studies, show that silicic magmatism was both widespread across the northern New England Fold Belt (>250 000 km 2 and >500 km inboard of plate margin) and protracted, occurring over a period of -15 million years. Zircon inheritance is commonplace in the Late Devonian - Early Carboniferous volcanics, reflecting anatectic melting and considerable reworking of continental crust. Inherited zircon components range from ca 370 to ca 2050 Ma, with Middle Devonian (385-370 Ma) zircons being common to almost all dated units. Precambrian zircon components record either Precambrian crystalline crust or sedimentary accumulations that were present above or within the zone of magma formation This contrasts with a lack of significant zircon inheritance in younger Permo-Carboniferous igneous rocks intruded through,and emplaced on top of, the Devonian-Carboniferous successions. The inheritance data and location of these volcanic rocks at the eastern margins of the northern New England Fold Belt, coupled with Sr-Nd, Pb isotopic data and depleted mantle model ages for Late Palaeozoic and Mesozoic magmatism, imply that Precambrian mafic and felsic crustal materials (potentially as old as 2050 Ma), or at the very least Lower Palaeozoic rocks derived from the reworking of Precambrian rocks, comprise basement to the eastern parts of the fold belt. This crustal basement architecture may be a relict from the Late Proterozoic breakup of the Rodinian supercontinent. Copyright (2004) Geological Society of Australia

Small-scale cyclic deposition in the Frasnian (Upper Devonian) of the Holy Cross Mountains, Poland

Science.gov (United States)

Vierek, Aleksandra

2014-12-01

In sections exposing Frasnian limestones at five outcrops in the Holy Cross Mountains, five lithofacies (L1 to L5) that represent upper slope to basinal environments are identified. These lithofacies are characterised by dark-coloured micritic limestones-marly shale couplets with many light-coloured intercalations of fine- to coarse-grained limestones (= event beds). This lithofacies pattern characterises mostly low-energy domains punctuated by storm episodes. In addition, these upper-slope to basinal lithofacies are arranged into small-scale, coarsening-upward beds and cycles. The cycles are locally composed of fining/thinning-upward beds. The small-scale cycles have a calculated duration of 19 to 42 kyr. The differential thickness of beds and cycles within and between sections was probably caused by differential subsidence and local tectonics. Possible evidence of tectonic activity is also related to a difference in number of cycles recorded in the time-equivalent sections. The recognised cyclicity shows sea-level fluctuations and a few deepening episodes. Some of them are correlated with the Timan global eustatic events. However, local tectonics and episodic subsidence may have played a significant role in recording brief deepening pulses. Thus, low-amplitude sea-level changes were major factors in platform generation and evolution in the Frasnian of the Holy Cross Mountains modified by local, block-related subsidence.

Small-scale cyclic deposition in the Frasnian (Upper Devonian of the Holy Cross Mountains, Poland

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Vierek Aleksandra

2014-12-01

Full Text Available In sections exposing Frasnian limestones at five outcrops in the Holy Cross Mountains, five lithofacies (L1 to L5 that represent upper slope to basinal environments are identified. These lithofacies are characterised by dark-coloured micritic limestones-marly shale couplets with many light-coloured intercalations of fine- to coarse-grained limestones (= event beds. This lithofacies pattern characterises mostly low-energy domains punctuated by storm episodes. In addition, these upper-slope to basinal lithofacies are arranged into small-scale, coarsening-upward beds and cycles. The cycles are locally composed of fining/thinning-upward beds. The small-scale cycles have a calculated duration of 19 to 42 kyr. The differential thickness of beds and cycles within and between sections was probably caused by differential subsidence and local tectonics. Possible evidence of tectonic activity is also related to a difference in number of cycles recorded in the time-equivalent sections. The recognised cyclicity shows sea-level fluctuations and a few deepening episodes. Some of them are correlated with the Timan global eustatic events. However, local tectonics and episodic subsidence may have played a significant role in recording brief deepening pulses. Thus, low-amplitude sea-level changes were major factors in platform generation and evolution in the Frasnian of the Holy Cross Mountains modified by local, block-related subsidence.

Global iridium anomaly, mass extinction, and redox change at the Devonian-Carboniferous boundary

Energy Technology Data Exchange (ETDEWEB)

Wang, K. (Geological Survey of Canada, Calgary, Alberta (Canada) Univ. of Calgary, Alberta (Canada)); Attrep, M. Jr.; Orth, C.J. (Los Alamos National Lab., NM (United States))

1993-12-01

Iridium abundance anomalies have been found on a global scale in the Devonian-Carboniferous (D-C) boundary interval, which records one of the largest Phanerozoic mass-extinction events, an event that devastated many groups of living organisms, such as plants, ammonoids, trilobites, conodonts, fish, foraminiferans, brachiopods, and ostracodes. At or very close to the D-C boundary, there exists a geographically widespread black-shale interval, and Ir abundances reach anomalous maxima of 0.148 ppb (Montagne Noire, France), 0.138 ppb (Alberta, Canada) 0.140 ppb (Carnic Alps, Austria), 0.156 ppb (Guangxi, China), 0.258 ppb (Guizhou, China), and 0.250 ppb (Oklahoma). The discovery of global D-C Ir anomalies argues for an impact-extinction model. However, nonchondritic ratios of Ir to other important elements and a lack of physical evidence (shocked quartz, microtektites) do not support such a scenario. The fact that all Ir abundance maxima are at sharp redox boundaries in these sections leads us to conclude that the Ir anomalies likely resulted from a sudden change in paleo-redox conditions during deposition and/or early diagenesis. 36 refs., 2 figs., 1 tab.

Partial preservation of the Tentaculites Crotalinus shell from Ponta Grossa Formation (Devonian)

International Nuclear Information System (INIS)

Ciguel, J.H.G.; Roesler, O.

1988-01-01

This paper deals with an analysis of a single specimen of Tentaculites crotalinus SALTER emend. CIGUEL et al. (1984) that present a possible partial preservation of the shell. It comes from an outcrop of the Grossa Formation (Devonian) near Jaguariaiva, State of Parana. The skeletal microstructure of the Tentaculitoidea shell rather poorly Known. Thus, the phylogenetic relationships of these invertebrates still uncertain. Tentaculitids are very common fossils in Devonian Ponta Grossa Formation (Parana Basin) but so far Known only from external and internal moulds. The objective of this study is to demonstrate wheter the layer found in between the internal and external mould is or not a case shell preservation. The chemical composition of this layer and of the external mould was analysed by X rays. X rays difratometry was applied only to the matrix (at the external mould). The structure of the supposed shell remain was studied by binocular stereomicroscope and scanning electron microscope. It revealed a foliate structure due to several paralel to subparalel oriented lamelae, with a chemical composition distinct from the matrix, and some elements possibly mantained from the original shell composition. Thus, a partial preservation of the original shell seems to be the better explanation for this case. This shell would be composed by calcium carbonate disposed in laminar layers, the outer ones being impregnated by Fe and Mn molecules during the diagenetic processes. The skeletal composition and microstructure would suggest a molluscan affinity for the tentaculitida Order. (auThor) [pt

Investigation of mineral composition of differently treated devonian, quaternary and triassic clays of Latvia

International Nuclear Information System (INIS)

Kosorukovs, A.; Viss, R.

1999-01-01

Clayey fractions (particle size less than 5 μm )of the Latvian Devonian (Kuprava and Liepa deposits), Quaternary (Laza and Ugale deposits) and Triassic (Akmene deposit, Republic of Lithuania) clays have been obtained. The clayey fractions were converted in the form in which all the cations were exchanged for magnesium ions. After the ion exchange the fractions were treated with dimethyl sulfoxide or glycerol in the course for two days, one sample being subjected to thermal treatment at 550±110 C for two hours. Diffractograms for the treated samples have been obtained using a DRON-2,0 diffractometer (Co-radiation). Analysis of the obtained diffractograms show that: 1) the main clayey minerals of the Devonian clays occur to be hydromicas (mainly hydromuscovite) containing admixtures of kaolinite and quartz; 2) the main clayey minerals of the Quarternary clays also occur to be hydromicas - mixtures of hydrobiotite and hydromuscovite containing admixtures of kaolinite and iron-containing chlorite; 3) smectite occurs to be the main mineral of the Triassic clay; it contains admixtures of hydromica and chlorite; 4) the Triassic and Quaternary clays contain fine- and coarse-grained carbonates, mainly calcite, in quantities of 10-16%; 5) iron and titanium are included in fine grained minerals. (author)

Middle Devonian palynomorphs from southern Moravia: an evidence of rapid change from terrestrial deltaic plain to carbonate platform conditions

Czech Academy of Sciences Publication Activity Database

Vavrdová, Milada; Dašková, Jiřina

2011-01-01

Roč. 62, č. 2 (2011), s. 109-119 ISSN 1335-0552 Institutional research plan: CEZ:AV0Z30130516 Keywords : Devonian marine transgression * basal elastics * miospores * acritarchs Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.787, year: 2011

Conodont biostratigraphy and depositional history of the Middle Devonian to Lower Carboniferous in the Cantabrian zone (Cantabrian Mountains, Spain)

NARCIS (Netherlands)

Raven, J.G.M.

1983-01-01

Within the Cantabrian zone during the Devonian and Early Carboniferous three large palaeogeographical units were of importance: the Asturian geanticline, the Palencian basin and the Asturo-Leonesian basin. These units have a different history of sedimentation, particularly the Palencian basin.

Devonian/Carboniferous boundary glacioeustatic fluctuations in a platform-to-basin direction: A geochemical approach of sequence stratigraphy in pelagic settings

Czech Academy of Sciences Publication Activity Database

Bábek, O.; Kumpan, T.; Kalvoda, J.; Matys Grygar, Tomáš

2016-01-01

Roč. 337, MAY (2016), s. 81-99 ISSN 0037-0738 Institutional support: RVO:61388980 Keywords : Element geochemistry * Hangenberg event * Glacioeustasy * Devonian/Carboniferous boundary * Sedimentation rate Subject RIV: DD - Geochemistry Impact factor: 2.373, year: 2016

Outlook of searching for oil and gas formations in the lower Frasnian-middle Devonian oil and gas complex in northern regions of the Timano-Pechora Province

Energy Technology Data Exchange (ETDEWEB)

Aleksin, G.A.; Rapoport, B.I.; Rassomakhin, V.Y.; Rossikhin, Y.A.

1981-01-01

In the northern part of the Timano-Pechora Province, highly promising middle Devonian and lower Frasnian terrigenous deposits are broadly developed. Seismic exploration has established a reduction in thicknesses of the subdomanic deposits in the near-anticline zones of structures of the ancient formation which are associated with zones of oil and gas accumulation are confined to traps of nonanticlinal and mixed types. In order to realize the program for studying terrigenous deposits of the Devonian it is necessary to accelerate drilling of search and parametric wells 8 of Kumzha, 1 of Vydshor, and 1 of Nosovaya. It is necessary to begin drilling well 5 at the Laydozhskiy field in the anticline of the new elevation revealed from results of detailed seismic work. It is necessary to drill wells on the lower Paleozoic deposits at the Diyatynskiy, Myadloveyyakhskiy, Nyamyurkhitskiy, Sadayeginskiy, East Khoreyverskiy elevations of the North Khoreyverskiy Basin, on structures of the Sorokin swell, on the Malozemel'sko-Kolguyevskiy monocline. It is necessary to accelerate searches at the khyl'chuyuskiy, Yareyyuskiy, North Khar'yaginskiy, Inzyreyskiy and other areas of the Kolvinskiy megaswell. The most important primary task of investigating the lower Frasnian-middle Devonian complex is to trace the zones of development of terrigenous deposits of the middle Devonian and zones of their thinning, as well as to prepare all structures in these deposits for seismic exploration by MOGT.

Horizontal Devonian shale well, Columbia Natural Resources, Inc. 's, Pocohontas Development Corp. Well 21747, Martin County, Kentucky

Energy Technology Data Exchange (ETDEWEB)

Koziar, G.; Ahmad, M.M.; Friend, L.L.; Friend, M.L.; Rothman, E.M.; Stollar, R.L. (Columbia Gas System Service Corp., Columbus, OH (United States))

1991-05-01

Columbia Gas and the United States Department of Energy (DOE) have successfully completed field work on a horizontally drilled Devonian shale well located in Martin County, Kentucky. The objective of this cofunded project is to assess the effectiveness and economic feasibility of applying horizontal drilling and hydraulically fracturing stimulation techniques to enhance the extraction of natural gas from the Devonian shale. The well is comprised of three segments: a conventional vertical section, an angle build section and a horizontal section. The well reached a measured depth (MD) of 6263 feet, 3810 feet true vertical depth (TVD), with a horizontal displacement of 2812 feet achieved in the desired direction of N10{degrees}W. Both air and foam were used as drilling fluids. The vertical, lateral and tangent sections were drilled using conventional rotary drilling methods. Downhole motors were used to build angle. A total combined final open flow of 3.1 MMcfd was measured from all zones. Total well expenditures are approximately $1,460,000. Of this amount, $700,000 is directly related to the research and learning curve experience aspects. It is projected that the same horizontal well could be drilled with existing technology for $700,000. If advanced can be made in MWD systems for air drilling environments, wells of this type could be drilled routinely for $500,000. It appears that application of horizontal drilling will result in at least acceleration of gas production and possibly the addition of recoverable reserves from the Devonian shale. Production data, necessary to validate this statement, are also required to determine the economics. As we gain experience and technology advances, cost reductions will occur; this will result in economic improvement.

Peeking out of the basins: looking for the Late Devonian Kellwasser Event in the open ocean in the Central Asian Orogenic Belt, southwestern Mongolia

Science.gov (United States)

Thomas, R. M., Jr.; Carmichael, S. K.; Waters, J. A.; Batchelor, C. J.

2017-12-01

Two of the top five most devastating mass extinctions in Earth's history occurred during the Late Devonian (419.2 Ma - 358.9 Ma), and are commonly associated with the black shale deposits of the Kellwasser and Hangenberg ocean anoxia events. Our understanding of these extinction events is incomplete partly due to sample bias, as 95% of the field sites studying the Late Devonian are limited to continental shelves and continental marine basins, and 77% of these sites are derived from the Euramerican paleocontinent. The Samnuuruul Formation at the Hoshoot Shiveetiin Gol locality (HSG), located in southwestern Mongolia, offers a unique opportunity to better understand global oceanic conditions during the Late Devonian. The HSG locality shows a continuous sequence of terrestrial to marine sediments on the East Junggar arc; an isolated, open-ocean island arc within the Central Asian Orogenic Belt (CAOB). Samples from this near shore locality consist of volcanogenic silts, sands and immature conglomerates as well as calc-alkalic basalt lava flows. Offshore sections contain numerous limestones with Late Devonian fossil assemblages. Preliminary biostratigraphy of the associated marine and terrestrial sequences can only constrain the section to a general Late Devonian age, but TIMS analysis of detrital zircons from volcanogenic sediments from the Samnuuruul Formation in localities 8-50 km from the site suggests a late Frasnian age (375, 376 Ma). To provide a more precise radiometric age of the HSG locality, zircon geochronology using laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) will be performed at UNC-Chapel Hill. If the HSG section crosses the Frasnian-Famennian boundary, geochemical, mineralogical, and ichnological signatures of the Kellwasser Event are expected to be preserved, if the Kellwasser Event was indeed global in scope (as suggested by Carmichael et al. (2014) for analogous sites on the West Junggar arc in the CAOB). Black shale

Bibliography of the paleontology and paleoecology of the Devonian-Mississippian black-shale sequence in North America

Energy Technology Data Exchange (ETDEWEB)

Barron, L.S.; Ettensohn, F.R.

1980-06-01

The Devonian-Mississippian black-shale sequence is one of the most prominent and well-known stratigraphic horizons in the Paleozoic of the United States, yet the paleontology and its paleoecologic and paleoenvironmental implications are poorly known. This is in larger part related to the scarcity of fossils preserved in the shale - in terms of both diversity and abundance. Nonetheless, that biota which is preserved is well-known and much described, but there is little synthesis of this data. The first step in such a synthesis is the compilation of an inclusive bibliography such as this one. This bibliography contains 1193 entries covering all the major works dealing with Devonian-Mississippian black-shale paleontology and paleoecology in North America. Articles dealing with areas of peripheral interest, such as paleogeography, paleoclimatology, ocean circulation and chemistry, and modern analogues, are also cited. In the index, the various genera, taxonomic groups, and other general topics are cross-referenced to the cited articles. It is hoped that this compilation will aid in the synthesis of paleontologic and paleoecologic data toward a better understanding of these unique rocks and their role as a source of energy.

Synthesis of 10-Ethyl Flavin: A Multistep Synthesis Organic Chemistry Laboratory Experiment for Upper-Division Undergraduate Students

Science.gov (United States)

Sichula, Vincent A.

2015-01-01

A multistep synthesis of 10-ethyl flavin was developed as an organic chemistry laboratory experiment for upper-division undergraduate students. Students synthesize 10-ethyl flavin as a bright yellow solid via a five-step sequence. The experiment introduces students to various hands-on experimental organic synthetic techniques, such as column…

Horizontal Devonian shale well, Columbia Natural Resources, Inc.`s, Pocohontas Development Corp. Well 21747, Martin County, Kentucky. Final report

Energy Technology Data Exchange (ETDEWEB)

Koziar, G.; Ahmad, M.M.; Friend, L.L.; Friend, M.L.; Rothman, E.M.; Stollar, R.L. [Columbia Gas System Service Corp., Columbus, OH (United States)

1991-05-01

Columbia Gas and the United States Department of Energy (DOE) have successfully completed field work on a horizontally drilled Devonian shale well located in Martin County, Kentucky. The objective of this cofunded project is to assess the effectiveness and economic feasibility of applying horizontal drilling and hydraulically fracturing stimulation techniques to enhance the extraction of natural gas from the Devonian shale. The well is comprised of three segments: a conventional vertical section, an angle build section and a horizontal section. The well reached a measured depth (MD) of 6263 feet, 3810 feet true vertical depth (TVD), with a horizontal displacement of 2812 feet achieved in the desired direction of N10{degrees}W. Both air and foam were used as drilling fluids. The vertical, lateral and tangent sections were drilled using conventional rotary drilling methods. Downhole motors were used to build angle. A total combined final open flow of 3.1 MMcfd was measured from all zones. Total well expenditures are approximately $1,460,000. Of this amount, $700,000 is directly related to the research and learning curve experience aspects. It is projected that the same horizontal well could be drilled with existing technology for $700,000. If advanced can be made in MWD systems for air drilling environments, wells of this type could be drilled routinely for $500,000. It appears that application of horizontal drilling will result in at least acceleration of gas production and possibly the addition of recoverable reserves from the Devonian shale. Production data, necessary to validate this statement, are also required to determine the economics. As we gain experience and technology advances, cost reductions will occur; this will result in economic improvement.

Strontium chemostratigraphy of carbonate sediments - Pilot study of Silurian and Devonian brachiopods from the Prague Basin

Czech Academy of Sciences Publication Activity Database

Janoušek, V.; Hladil, Jindřich; Frýda, J.; Slavík, Ladislav; Šmíd, J.

2001-01-01

Roč. 13, - (2001), s. 68-69 ISSN 1210-9606. [Meeting of the Czech Tectonics Studies Group /6./. Donovaly - Nízké Tatry, 03.05.2001-06.05.2001] R&D Projects: GA AV ČR KSK3012103 Institutional research plan: CEZ:AV0Z3013912 Keywords : strontium chemostratigraphy * aquafacies * Devonian Subject RIV: DB - Geology ; Mineralogy http://geolines.gli.cas.cz/fileadmin/volumes/volume13/G13-068b.pdf

Toward an exact age of Middle Devonian Čelechovice corals - past problems in biostratigraphy and present solutions complemented by new magnetosusceptibility measurements

Czech Academy of Sciences Publication Activity Database

Hladil, Jindřich; Pruner, Petr; Venhodová, Daniela; Hladilová, T.; Man, Otakar

2002-01-01

Roč. 7, - (2002), s. 65-71 ISSN 0945-7275 R&D Projects: GA AV ČR IAA3013802 Institutional research plan: CEZ:AV0Z3013912 Keywords : magnetosusceptibility stratigraphy * Devonian * Moravia Subject RIV: DB - Geology ; Mineralogy

The hyper-enrichment of V and Zn in black shales of the Late Devonian-Early Mississippian Bakken Formation (USA)

Science.gov (United States)

Scott, Clinton T.; Slack, John F.; Kelley, Karen Duttweiler

2017-01-01

Black shales of the Late Devonian to Early Mississippian Bakken Formation are characterized by high concentrations of organic carbon and the hyper-enrichment (> 500 to 1000s of mg/kg) of V and Zn. Deposition of black shales resulted from shallow seafloor depths that promoted rapid development of euxinic conditions. Vanadium hyper-enrichments, which are unknown in modern environments, are likely the result of very high levels of dissolved H2S (~ 10 mM) in bottom waters or sediments. Because modern hyper-enrichments of Zn are documented only in Framvaren Fjord (Norway), it is likely that the biogeochemical trigger responsible for Zn hyper-enrichment in Framvaren Fjord was also present in the Bakken basin. With Framvaren Fjord as an analogue, we propose a causal link between the activity of phototrophic sulfide oxidizing bacteria, related to the development of photic-zone euxinia, and the hyper-enrichment of Zn in black shales of the Bakken Formation.

Geological investigation of shaft mine in Devonian limestone in Kansas City, Missouri and other potentially dry excavated subsurface space in part of the Forest City Basin

Energy Technology Data Exchange (ETDEWEB)

Goebel, E.D.

1977-10-01

A high quality limestone is currently being mined from a deep shaft mine (1072 feet) in Middle Devonian rocks (Callaway) within the city limits of Kansas City, Missouri. About 15 acres of essentially dry space (room and pillar) with up to 14-foot ceilings have been developed. There are few natural joints observable in the rock within the mine. Some of these are periodically damp. More than 80% of the mine is dry. Saltwater from aquifers (Pennsylvanian) cut by the shaft accumulates behind the shaft at the pump station at 850 feet and at the bottom of the shaft (Devonian-Ordovician rocks). As long as the pumps lift the water to the surface, the mine can be kept relatively dry. Grouting of the aquifer's rocks in the shaft may seal off that source of water. The Burlington limestone of the Mississippian System is potentially mineable on the property now developed. The Burlington limestone, the Middle Devonian limestone, and the Kimmswick (Middle Ordovician) limestone are all potentially mineable by shaft mining in the northern part of Greater Kansas City and northward into the Forest City Basin.

Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus

Science.gov (United States)

Johanson, Zerina; Smith, Moya; Sanchez, Sophie; Senden, Tim; Trinajstic, Kate; Pfaff, Cathrin

2017-07-01

Palaeospondylus gunni Traquair, 1890 is an enigmatic Devonian vertebrate whose taxonomic affinities have been debated since it was first described. Most recently, Palaeospondylus has been identified as a stem-group hagfish (Myxinoidea). However, one character questioning this assignment is the presence of three semicircular canals in the otic region of the cartilaginous skull, a feature of jawed vertebrates. Additionally, new tomographic data reveal that the following characters of crown-group gnathostomes (chondrichthyans + osteichthyans) are present in Palaeospondylus: a longer telencephalic region of the braincase, separation of otic and occipital regions by the otico-occipital fissure, and vertebral centra. As well, a precerebral fontanelle and postorbital articulation of the palatoquadrate are characteristic of certain chondrichthyans. Similarities in the structure of the postorbital process to taxa such as Pucapampella, and possible presence of the ventral cranial fissure, both support a resolution of Pa. gunni as a stem chondrichthyan. The internally mineralized cartilaginous skeleton in Palaeospondylus may represent a stage in the loss of bone characteristic of the Chondrichthyes.

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

The morphogroups of small agglutinated foraminifera from the Devonian carbonate complex of the Prague Synform, (Barrandian area, Czech Republic)

Czech Academy of Sciences Publication Activity Database

Holcová, K.; Slavík, Ladislav

2013-01-01

Roč. 386, č. 5 (2013), s. 210-214 ISSN 0031-0182 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100131201 Institutional support: RVO:67985831 Keywords : Barrandian area * Early Devonian * foraminifera * morphogroups Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.752, year: 2013

The sedimentary record and petrophysical logs from the Spanish Central Pyrenees: Implications for paleoclimate change in the Early Devonian

Czech Academy of Sciences Publication Activity Database

Slavík, Ladislav; Valenzuela-Ríos, J. I.; Hladil, Jindřich; Chadimová, Leona; Liao, J-Ch.; Hušková, Aneta; Calvo, H.; Hrstka, Tomáš

2015-01-01

Roč. 21, - (2015), s. 350-350 ISSN 1608-8166. [International Congress on Stratigraphy /2./. STRATI 2015. 19.07.2015-23.07.2015, Graz] Institutional support: RVO:67985831 Keywords : stratigraphy * Early Devonian * sedimentary record * paleoclimate change * Spanish Central Pyrenees Subject RIV: DB - Geology ; Mineralogy http://www.zobodat.at/pdf/Ber-Inst-Erdwiss-Univ-Graz_21_0001-0437.pdf

A Porolepiform Rhipidistian from the Lower Devonian of the Canadian Arctic

Directory of Open Access Journals (Sweden)

H.-P. Schultze

2000-01-01

Full Text Available A holoptychiid fish is described from the Lower Devonian of Arctic Canada. The new form is distinct from other holoptychiids by the presence of a large supraorbital bone and a boomerang-shaped tabular. Nasogaluakus n. gen. is the oldest and most primitive holoptychiid based on a phylogenetic analysis of porolepiforms and their closest relatives. The sequence of the genera corresponds to their stratigraphic appearance. Ein Holoptychiide aus dem Unterdevon der kanadischen Arktis wird beschrieben. Er unterscheidet sich durch ein großes Supraorbitale und die Bumerang-Form des Tabulare von allen übrigen Holoptychiiden. Nasogaluakus n. gen. ist der älteste und primitivste Holoptychiide, was durch eine phylogenetische Analyse der Porolepiformes belegt wird. Die Abfolge der Gattungen in diesem Verwandtschaftsschema stimmt mit ihrem zeitlichen Auftreten überein. doi:10.1002/mmng.20000030106

Impact Ejecta Layer from the Mid-Devonian: Possible Connection to Global Mass Extinctions

Science.gov (United States)

Ellwood, Brooks B.; Benoist, Stephen L.; Hassani, Ahmed El; Wheeler, Christopher; Crick, Rex E.

2003-06-01

We have found evidence for a bolide impacting Earth in the mid-Devonian (~380 million years ago), including high concentrations of shocked quartz, Ni, Cr, As, V, and Co anomalies; a large negative carbon isotope shift (-9 per mil); and microspherules and microcrysts at Jebel Mech Irdane in the Anti Atlas desert near Rissani, Morocco. This impact is important because it is coincident with a major global extinction event (Kacák/otomari event), suggesting a possible cause-and-effect relation between the impact and the extinction. The result may represent the extinction of as many as 40% of all living marine animal genera.

A microanatomical and histological study of the postcranial dermal skeleton of the Devonian actinopterygian Cheirolepis canadensis

Directory of Open Access Journals (Sweden)

Louise Zylberberg

2016-06-01

Full Text Available The Devonian stem-actinoterygian Cheirolepis canadensis is potentially important to understand the evolution of the dermal skeleton of osteichthyans, but the last detailed histological study on this taxon was published more than forty years ago. Here, we present new data about the morphology and the histological structure of scales, fulcra, and fin-rays in the Devonian actinopterygian Cheirolepis canadensis through SEM and photomicroscopy. The scales have a typical palaeoniscoid organisation, with ganoine layers overlaying dentine and a bony basal plate, but the ganoine surface lacks the characteristic microtubercles that have been described on the ganoine surface of the scales of polypterids and many other actinopterygians. Fin-rays are composed of segmented and ramified lepidotrichia that show a structure reminiscent of scales, with ganoine and dentine components lying on a thick bony base. We describe articular processes between lepidotrichia that are reminiscent of, and plausibly homologous with, the peg-and-socket articulations between the scales. The analysis of the postcranial dermal skeleton of Cheirolepis canadensis shows that structural similarities between scales and lepidotrichia of this basal actinopterygian are greater than in more recent actinopterygians. The new data on histological and microanatomical structure of the dermal skeleton lend additional support to the hypothesis that lepidotichia are derivatives of scales, though they are also compatible with the more general hypothesis that scales, lepidotrichia and fulcra belong to the same morphogenetic system.

A global cyclostratigraphic framework constrains the timing and pacing of environmental changes over the Late Devonian (Frasnian - Famennian) mass extinction

Science.gov (United States)

De Vleeschouwer, David; Da Silva, Anne-Christine; Day, James E.; Whalen, Michael; Claeys, Philippe

2016-04-01

Milankovitch cycles (obliquity, eccentricity and precession) result in changes in the distribution of solar energy over seasons, as well as over latitudes, on time scales of ten thousands of years to millions of years. These changing patterns in insolation have induced significant variations in Earth's past climate over the last 4.5 billion years. Cyclostratigraphy and astrochronology utilize the geologic imprint of such quasi-cyclic climatic variations to measure geologic time. In recent years, major improvements of the Geologic Time Scale have been proposed through the application of cyclostratigraphy, mostly for the Mesozoic and Cenozoic (Gradstein et al., 2012). However, the field of Paleozoic cyclostratigraphy and astrochronology is still in its infancy and the application of cyclostratigraphic techniques in the Paleozoic allows for a whole new range of research questions. For example, unraveling the timing and pacing of environmental changes over the Late Devonian mass extinction on a 105-year time-scale concerns such a novel research question. Here, we present a global cyclostratigraphic framework for late Frasnian to early Famennian climatic and environmental change, through the integration of globally distributed sections. The backbone of this relative time scale consists of previously published cyclostratigraphies for western Canada and Poland (De Vleeschouwer et al., 2012; De Vleeschouwer et al., 2013). We elaborate this Euramerican base by integrating new proxy data -interpreted in terms of astronomical climate forcing- from the Iowa basin (USA, magnetic susceptibility and carbon isotope data) and Belgium (XRF and carbon isotope data). Next, we expand this well-established cyclostratigraphic framework towards the Paleo-Tethys Ocean, using magnetic susceptibility and carbon isotope records from the Fuhe section in South China (Whalen et al., 2015). The resulting global cyclostratigraphic framework implies an important refinement of the late Frasnian to

Environmental changes close to the Lower-Middle Devonian boundary; the Basal Choteč Event in the Prague Basin (Czech Republic)

Czech Academy of Sciences Publication Activity Database

Vodrážková, S.; Frýda, J.; Suttner, T. J.; Koptíková, Leona; Tonarová, P.

2013-01-01

Roč. 59, č. 2 (2013), s. 425-449 ISSN 0172-9179 R&D Projects: GA ČR GAP210/10/2351 Institutional support: RVO:67985831 Keywords : Basal Choteč Event * carbon isotope geochemistry * environmental changes * Lower-Middle Devonian * microfacies analysis * Prague Basin Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.338, year: 2013

Petrogenesis of the Mairupt microgranite: A witness of an Uppermost Silurian magmatism in the Rocroi Inlier, Ardenne Allochton

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Cobert, Corentin; Baele, Jean-Marc; Boulvais, Philippe; Poujol, Marc; Decrée, Sophie

2018-03-01

Magmatism in the Rocroi inlier (Ardenne Allochton, southeastern Avalonia during eo-Hercynian times) consists of a swarm of bimodal dykes (diabase and/or microgranite) emplaced in Middle to Upper Cambrian siliciclastics (Revin Group). Felsic volcanites interbedded within the Upper Silurian/Lower Devonian transgressive strata on the eastern edge of the inlier were interpreted as belonging to the same magmatic event. This was subsequently invalidated by zircon U-Pb dating of the Mairupt and Grande Commune magmatic rocks, which yielded an Upper Devonian age. Here we report a reevaluation of the age of the Mairupt microgranite based on LA-ICP-MS in situ U-Pb zircon geochronology, which yields a concordant age of 420.5 ± 2.9 Ma (Late Silurian/Early Devonian). This new dating restores the consistency between the different magmatic occurrences in the Rocroi inlier. The geochemical and petrographical data furthermore indicate a major crustal contribution, which fits well within the context of crust thinning of the Ardenne margin (southeastern Avalonia) in the transtensional Rheno-Hercynian back-arc basin.

Devonian paleomagnetism of the North Tien Shan: Implications for the middle-Late Paleozoic paleogeography of Eurasia

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Levashova, Natalia M.; Mikolaichuk, Alexander V.; McCausland, Philip J. A.; Bazhenov, Mikhail L.; Van der Voo, Rob

2007-05-01

The Ural-Mongol belt (UMB), between Siberia, Baltica and Tarim, is widely recognized as the locus of Asia's main growth during the Paleozoic, but its evolution remains highly controversial, as illustrated by the disparate paleogeographic models published in the last decade. One of the largest tectonic units of the UMB is the Kokchetav-North Tien Shan Domain (KNTD) that stretches from Tarim in the south nearly to the West Siberian Basin. The KNTD comprises several Precambrian microcontinents and numerous remnants of Early Paleozoic island arcs, marginal basins and accretionary complexes. In Late Ordovician time, all these structures had amalgamated into a single contiguous domain. Its paleogeographic position is of crucial importance for elucidating the Paleozoic evolution of the UMB in general and of the Urals in particular. The Aral Formation, located in Kyrgyzstan in the southern part of the KNTD, consists of a thick Upper Devonian (Frasnian) basalt-andesite sequence. Paleomagnetic data show a dual-polarity characteristic component (Dec/Inc = 286° / + 56°, α95 = 9°, k = 21, N = 15 sites). The primary origin of this magnetization is confirmed by a positive test on intraformational conglomerates. We combine this result with other Paleozoic data from the KNTD and show its latitudinal motion from the Late Ordovician to the end of the Paleozoic. The observed paleolatitudes are found to agree well with the values extrapolated from Baltica to a common reference point (42.5°N, 73°E) in our sampling area for the entire interval; hence coherent motion of the KNTD and Baltica is strongly indicated for most of the Paleozoic. This finding contradicts most published models of the UMB evolution, where the KNTD is separated from Baltica by a rather wide Ural Ocean containing one or more major plate boundaries. An exception is the model of Şengör and Natal'in [A.M.C. Şengör, B.A. Natal'in, Paleotectonics of Asia: fragments of a synthesis, in: A. Yin and M. Harrison (eds

Petrogenesis of the postcollisional Middle Devonian monzonitic to granitic magmatism of the Sierra de San Luis, Argentina

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López de Luchi, Mónica G.; Siegesmund, Siegfried; Wemmer, Klaus; Nolte, Nicole

2017-09-01

Middle Devonian granitoids intruded the Eastern Sierras Pampeanas basement ca. 600 km east of the inferred proto-Pacific margin of Gondwana along which a ca. 390 Ma collisional event developed. In the Sierra de San Luis, voluminous Middle Devonian (393-382 Ma) batholiths are composed of I- to A-type hybrid Monzonite and Granite suites. Shoshonite and subordinated high-K series, stocks, synplutonic dikes and enclaves make up the Monzonite Suite; rocks are metaluminous alkali-calcic magnesian porphyritic or equigranular monzonite, quartz monzonite, monzodiorite and scarce monzogabbro. High-K and subordinated shoshonite series metaluminous to mildly peraluminous magnesian alkali-calcic to calc-alkalic porphyritic or equigranular quartz monzonite, granodiorite, monzogranite and equigranular leucomonzogranites make up the Granite Suite plutons and batholiths. Only a small group of highly evolved granites are ferroan. SiO2 (46-62%), Cr, Ni, V, Sc, LILE, LREE, Th, Zr and variable, Sr/Y, (La/Yb)N and (Tb/Yb)N, smooth Eu/Eu*, moderate Na2O (ca 3.5), and troughs at Nb and Ta for Monzonite Suite rocks suggest an subduction-related enriched lithospheric mantle source. Sm-Nd data (TDM 0.98-1.08 Ga, εNd(380 Ma) 0.66-1.47) and 87Sr/86Sri (0.703520-0.704203) are compatible with an enriched mantle source. The metaluminous porphyritic quartz monzonite-monzogranite and the mildly peraluminous equigranular biotite monzogranites of the Granite Suite are characterized by relatively moderate Al2O3, CaO, and 87Sr/86Sri, high LILE, Cr, variable Sr/Y, (La/Yb)N and Eu/Eu* and low Rb/Sr ( 1.5, ASI 1.05-1.18, and Ga/Al 2.6-3.9, εNd(380 Ma) - 3.74 to - 3.95 and (87Sr/86Sr)i 0.710743-0.712955 which would point to metasedimentary or felsic igneous crustal sources. Nevertheless their TDM 1.36-1.38 Ga is considerably younger than the mean 1.8-1.6 Ga Eastern Sierras Pampeanas crustal residence age and less radiogenic. Middle Devonian magmatism would record an episode of crustal growth by enriched

LATE DEVONIAN-CARBONIFEROUS CONODONTS FROM EASTERN IRAN

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MEHDI YAZDI

1999-07-01

Full Text Available Conodont data from acid-leaching 110 samples from two Late Devonian-Carboniferous areas in the Shotori Range (Tabas region of eastern Iran are presented. At Howz-e-Dorah, a section (88 samples commencing high in the Bahram Formation (Givetian-early Frasnian extended through the Shishtu Formation (Frasnian, Early hassi Zone or older, to latest Tournaisian, anchoralis-latus Zone and the Sardar Formation (earliest Visean, texanus Zone, to late Namurian, sinuatus-corrugatus-sulcatus Zone and into the Jamal Formation (Permian. Four less exhaustively sampled sections (22 samples show the Kale Sardar area to be tectonically more complicated than the Howz-e-Dorah area. Useful marker horizons in the Howz-e-Dorah section, well constrained by conodont data, are: the early Frasnian (no older than Early hassi Zone biostromal beds of the Shishtu Formation, an early Famennian (Late triangularis to Early crepida interval of oolitic limestone, a cyclothem sequence straddling the Early Carboniferous-Late Carboniferous boundary, and an Early Permian interval of siliceous sand ("the white quartzite" of previous authors. Additionally, several iron-rich horizons, readily traceable from locality to locality, are well constrained by conodont ages. Eighty-five conodont species/subspecies are documented representing 24 genera.. Two new species, Polygnathus capollocki and Polygnathus ratebi and one new subspecies, Icriodus alternatus mawsonae are described. 

Ontogenetic and intraspecific variation in the late Emsian - Eifelian (Devonian) conodonts Polygnathus serotinus and P. bultyncki in the Prague Basin (Czech Republic) and Nevada (western U.S.)

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Klapper, Gilbert; Vodrážková, Stanislava

2013-06-01

Klapper, G. and Vodražkova, S. 2013. Ontogenetic and intraspecific variation in the late Emsian - Eifelian (Devonian) conodonts Polygnathus serotinus and P. bultyncki in the Prague Basin (Czech Republic) and Nevada (western U.S.). Acta Geologica Polonica, 63 (2), 153-174, Warszawa. Samples from populations of Polygnathus serotinus Telford 1975 and P. bultyncki Weddige 1977 from the Prague Basin and Nevada display normal variation for Devonian conodont species. A considerable number of previous authors, however, have proposed unnecessary synonyms of these two species, primarily because they have not recognized ontogenetic variation. In contrast, we interpret the variation as ontogenetic as well as intraspecific and present detailed synonymies as a result. A third species, P. praetrigonicus Bardashev 1992, which has been carried in open nomenclature for many years, is an important indicator of the basal costatus Zone in the Prague Basin, New York, and Nevada. We review the stratigraphic distribution of these three species and the conodont zonation across the Emsian-Eifelian (Lower-Middle Devonian) boundary. Polygnathus pseudocostatus sp. nov. (partitus-costatus zones, central Nevada) is described herein. We have observed a decrease in the pit size during ontogeny in P. bultyncki although we have not measured enough specimens to rule out intraspecific versus ontogenetic variation.

A review of the organic geochemistry of shales

International Nuclear Information System (INIS)

Ho, P.C.; Meyer, R.E.

1987-06-01

Shale formations have been suggested as a potential site for a high level nuclear waste repository. As a first step in the study of the possible interaction of nuclides with the organic components of the shales, literature on the identification of organic compounds from various shales of the continent of the United States has been reviewed. The Green River shale of the Cenozoic era is the most studied shale followed by the Pierre shale of the Mesozoic era and the Devonian black shale of the Paleozoic era. Organic compounds that have been identified from these shales are hydrocarbons, fatty acids, fatty alcohols, steranes, terpanes, carotenes, carbohydrates, amino acids, and porphyrins. However, these organic compounds constitute only a small fraction of the organics in shales and the majority of the organic compounds in shales are still unidentified

First shark from the Late Devonian (Frasnian) Gogo Formation, Western Australia sheds new light on the development of tessellated calcified cartilage.

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Long, John A; Burrow, Carole J; Ginter, Michal; Maisey, John G; Trinajstic, Kate M; Coates, Michael I; Young, Gavin C; Senden, Tim J

2015-01-01

Living gnathostomes (jawed vertebrates) comprise two divisions, Chondrichthyes (cartilaginous fishes, including euchondrichthyans with prismatic calcified cartilage, and extinct stem chondrichthyans) and Osteichthyes (bony fishes including tetrapods). Most of the early chondrichthyan ('shark') record is based upon isolated teeth, spines, and scales, with the oldest articulated sharks that exhibit major diagnostic characters of the group--prismatic calcified cartilage and pelvic claspers in males--being from the latest Devonian, c. 360 Mya. This paucity of information about early chondrichthyan anatomy is mainly due to their lack of endoskeletal bone and consequent low preservation potential. Here we present new data from the first well-preserved chondrichthyan fossil from the early Late Devonian (ca. 380-384 Mya) Gogo Formation Lägerstatte of Western Australia. The specimen is the first Devonian shark body fossil to be acid-prepared, revealing the endoskeletal elements as three-dimensional undistorted units: Meckel's cartilages, nasal, ceratohyal, basibranchial and possible epibranchial cartilages, plus left and right scapulocoracoids, as well as teeth and scales. This unique specimen is assigned to Gogoselachus lynnbeazleyae n. gen. n. sp. The Meckel's cartilages show a jaw articulation surface dominated by an expansive cotylus, and a small mandibular knob, an unusual condition for chondrichthyans. The scapulocoracoid of the new specimen shows evidence of two pectoral fin basal articulation facets, differing from the standard condition for early gnathostomes which have either one or three articulations. The tooth structure is intermediate between the 'primitive' ctenacanthiform and symmoriiform condition, and more derived forms with a euselachian-type base. Of special interest is the highly distinctive type of calcified cartilage forming the endoskeleton, comprising multiple layers of nonprismatic subpolygonal tesserae separated by a cellular matrix, interpreted

First shark from the Late Devonian (Frasnian Gogo Formation, Western Australia sheds new light on the development of tessellated calcified cartilage.

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John A Long

Full Text Available Living gnathostomes (jawed vertebrates comprise two divisions, Chondrichthyes (cartilaginous fishes, including euchondrichthyans with prismatic calcified cartilage, and extinct stem chondrichthyans and Osteichthyes (bony fishes including tetrapods. Most of the early chondrichthyan ('shark' record is based upon isolated teeth, spines, and scales, with the oldest articulated sharks that exhibit major diagnostic characters of the group--prismatic calcified cartilage and pelvic claspers in males--being from the latest Devonian, c. 360 Mya. This paucity of information about early chondrichthyan anatomy is mainly due to their lack of endoskeletal bone and consequent low preservation potential.Here we present new data from the first well-preserved chondrichthyan fossil from the early Late Devonian (ca. 380-384 Mya Gogo Formation Lägerstatte of Western Australia. The specimen is the first Devonian shark body fossil to be acid-prepared, revealing the endoskeletal elements as three-dimensional undistorted units: Meckel's cartilages, nasal, ceratohyal, basibranchial and possible epibranchial cartilages, plus left and right scapulocoracoids, as well as teeth and scales. This unique specimen is assigned to Gogoselachus lynnbeazleyae n. gen. n. sp.The Meckel's cartilages show a jaw articulation surface dominated by an expansive cotylus, and a small mandibular knob, an unusual condition for chondrichthyans. The scapulocoracoid of the new specimen shows evidence of two pectoral fin basal articulation facets, differing from the standard condition for early gnathostomes which have either one or three articulations. The tooth structure is intermediate between the 'primitive' ctenacanthiform and symmoriiform condition, and more derived forms with a euselachian-type base. Of special interest is the highly distinctive type of calcified cartilage forming the endoskeleton, comprising multiple layers of nonprismatic subpolygonal tesserae separated by a cellular matrix

Method for calculation of upper limit internal alpha dose rates to aquatic organisms with application of plutonium-239 in plankton

International Nuclear Information System (INIS)

Paschoa, A.S.; Baptista, G.B.

1977-01-01

A method for the calculation of upper limit internal alpha dose rates to aquatic organisms is presented. The mean alpha energies per disintegration of radionuclides of interest are listed to be used in standard methodologies to calculate dose to aquatic biota. As an application, the upper limits for the alpha dose rates from 239 Pu to the total body of plankton are estimated based on data available in open literature [pt

Temporal-spatial reconstruction of the early Frasnian (Late Devonian) anoxia in NW Africa: new field data from the Ahnet Basin (Algeria)

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Lüning, S.; Wendt, J.; Belka, Z.; Kaufmann, B.

2004-01-01

Anoxic conditions were widespread in NW Africa during the early Frasnian (Late Devonian) that resulted in deposition of organic-rich shales and limestones with total organic carbon (TOC) values of up to 14%. Organic richness and thickness of these sediments vary laterally, and organic-rich vs. organic-poor facies boundaries are likely to have been diachronous. A precise temporal-spatial reconstruction of this anoxic phase in NW Africa is complicated because the organic matter in outcrops is largely oxidised and biostratigraphic resolution in boreholes is generally low due to the lack of recoverable conodonts. This contribution is based on eight outcrop sections at the margin of the central Algerian Ahnet Basin, where detailed spectral gamma-ray measurements were carried out using a handheld instrument. The pre-weathering organic richness in Frasnian outcrop sections is approximated using the characteristic uranium enrichment in the anoxic facies that, based on well studies, is positively correlated with the total organic carbon content. Conodont biostratigraphic results from these sections suggest that the uranium-enriched interval (the anoxic interval) at the basin margin is most common in the basal Frasnian conodont Biozones 1-2, confirming previous results from the Anti Atlas in Morocco. In three of the eight localities studied the basal Frasnian has not been deposited and the Frasnian here commences with distinctly younger uranium-enriched intervals, including Zones 4-11. Well data from the eastern Algerian Berkine Basin is interpreted to indicate a significantly longer anoxic phase there. Million-year-scale diachroneities of the Frasnian anoxia, therefore, clearly exist across the North Africa shelf. It is assumed that the palaeorelief might have been a major factor in controlling the onset, duration, and intensity of anoxia in the region.

Seven 365-Million-Year-Old Trilobites Moulting within a Nautiloid Conch

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Zong, Rui-Wen; Fan, Ruo-Ying; Gong, Yi-Ming

2016-10-01

A nautiloid conch containing many disarticulated exoskeletons of Omegops cornelius (Phacopidae, Trilobita) was found in the Upper Devonian Hongguleleng Formation of the northwestern margin of the Junggar Basin, NW China. The similar number of cephala, thoraces and pygidia, unbroken thoraces, explicit exuviae, and lack of other macrofossils in the conch, indicate that at least seven individual trilobites had moulted within the nautiloid living chamber, using the vacant chamber of a dead nautiloid as a communal place for ecdysis. This exuvial strategy manifests cryptic behaviour of trilobites, which may have resulted from the adaptive evolution induced by powerful predation pressure, unstable marine environments, and competition pressure of organisms occupying the same ecological niche in the Devonian period. The unusual presence of several trilobites moulting within a nautiloid conch is possibly associated with social behaviours in face of a serious crisis. New materials in this study open a window for understanding the survival strategy of marine benthic organisms, especially predator-prey interactions and the behavioural ecology of trilobites in the middle Palaeozoic.

Iron in the Middle Devonian aquifer system and its removal at Võru County water treatment plants, Estonia

OpenAIRE

Mariina Hiiob; Enn Karro

2012-01-01

Groundwater abstracted from the Middle Devonian aquifer system is the main source of drinking water in South Estonia. High iron and manganese concentrations in groundwater are the greatest problems in this region. The total iron concentrations up to 16 mg L–1 are mainly caused by a high Fe2+ content in water, pointing to the dominance of reducing conditions in the aquifer system. A pilot study was carried out to estimate the effectiveness of 20 groundwater purification plants with eight diffe...

Paramagnetic limiting of the upper critical field of the layered organic superconductor κ-(BEDT-TTF)2Cu(SCN)2

International Nuclear Information System (INIS)

Zuo, F.; Brooks, J.S.; McKenzie, R.H.; Schlueter, J.A.; Williams, J.M.

2000-01-01

We report detailed measurements of the interlayer magnetoresistance of the layered organic superconductor κ-(BEDT-TTF) 2 Cu(SCN) 2 for temperatures down to 0.5 K and fields up to 30 T. The upper critical field is determined from the resistive transition for a wide range of temperatures and field directions. For magnetic fields parallel to the layers, the upper critical field increases approximately linearly with decreasing temperature. The upper critical field at low temperatures is compared to the Pauli paramagnetic limit, at which singlet superconductivity should be destroyed by the Zeeman splitting of the electron spins. The measured value is comparable to a value for the paramagnetic limit calculated from thermodynamic quantities but exceeds the limit calculated from BCS theory. The angular dependence of the upper critical field shows a cusplike feature for fields close to the layers, consistent with decoupled layers.

Extensive upper respiratory tract sarcoidosis

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Soares, Mafalda Trindade; Sousa, Carolina; Garanito, Luísa; Freire, Filipe

2016-01-01

Sarcoidosis is a chronic granulomatous disease of unknown aetiology. It can affect any part of the organism, although the lung is the most frequently affected organ. Upper airway involvement is rare, particularly if isolated. Sarcoidosis is a diagnosis of exclusion, established by histological evidence of non-caseating granulomas and the absence of other granulomatous diseases. The authors report a case of a man with sarcoidosis manifesting as a chronic inflammatory stenotic condition of the upper respiratory tract and trachea. PMID:27090537

Overview of the stratigraphy and initial quantitative biogeographical results from the Devonian of the Albergaria-a-Velha Unit (Ossa-Morena Zone, W. Portugal)

Czech Academy of Sciences Publication Activity Database

Machado, G.; Vavrdová, Milada; Fonseca, P. E.; Chaminé, H.; Tavares Rocha, F.

2008-01-01

Roč. 64, 2-4 (2008), s. 109-113 ISSN 0036-5343 Institutional research plan: CEZ:AV0Z30130516 Keywords : Gondwana * Laurussia * Devonian * Ossa Morena Subject RIV: DB - Geology ; Mineralogy http://www.nm.cz/publikace/archiv-en.php?id=4&rok=64&kcislu=2-4&f_=Show

Strontium isotopes test long-term zonal isolation of injected and Marcellus formation water after hydraulic fracturing.

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Kohl, Courtney A Kolesar; Capo, Rosemary C; Stewart, Brian W; Wall, Andrew J; Schroeder, Karl T; Hammack, Richard W; Guthrie, George D

2014-08-19

One concern regarding unconventional hydrocarbon production from organic-rich shale is that hydraulic fracture stimulation could create pathways that allow injected fluids and deep brines from the target formation or adjacent units to migrate upward into shallow drinking water aquifers. This study presents Sr isotope and geochemical data from a well-constrained site in Greene County, Pennsylvania, in which samples were collected before and after hydraulic fracturing of the Middle Devonian Marcellus Shale. Results spanning a 15-month period indicated no significant migration of Marcellus-derived fluids into Upper Devonian/Lower Mississippian units located 900-1200 m above the lateral Marcellus boreholes or into groundwater sampled at a spring near the site. Monitoring the Sr isotope ratio of water from legacy oil and gas wells or drinking water wells can provide a sensitive early warning of upward brine migration for many years after well stimulation.

Shallow water mud-mounds of the Early Devonian Buchan Group, East Gippsland, Australia

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Tosolini, A.-M. P.; Wallace, M. W.; Gallagher, S. J.

2012-12-01

The Lower Devonian Rocky Camp Member of the Murrindal Limestone, Buchan Group of southeastern Australia consists of a series of carbonate mud-mounds and smaller lagoonal bioherms. The Rocky Camp mound is the best exposed of the mud-mounds and has many characteristics in common with Waulsortian (Carboniferous) mounds. Detailed paleoecological and sedimentological studies indicate that the mound initially accumulated in the photic zone, in contrast to most of the previously recorded mud-mounds. Five facies are present in the mud-mound: a Dasycladacean Wackestone Facies at the base of the mound represents a moderate energy, shallow water bank environment within the photic zone. A Crinioidal Wackestone Facies was deposited in a laterally equivalent foreslope setting. A Poriferan-Crinoidal Mudstone Facies developed in a quiet, deeper water, lee-side mound setting associated with a minor relative sea-level rise. A Stromatoporoid-Coralline Packstone Facies in the upper part of the mound deposited in a high-energy, fair-weather wave base, mound-front environment. The crest of the mound is represented by a Crinoidal-Receptaculitid Packstone Facies indicative of a moderate-energy mound-top environment in the photic zone, sheltered by the mound-front stromatoporoid-coral communities. A mound flank facies is present on the southern side of the mound and this consists of high-energy crinoidal grainstones. Mud-mound deposition was terminated by a transgression that deposited dark gray, fossil-poor marl of the overlying Taravale Formation. The Rocky Camp mound appears to have originated in shallow water photic zone conditions and grew into a high-energy environment, with the mound being eventually colonized by corals and stromatoporoids. The indications of a high-energy environment during later mound growth (growth form of colonial metazoans and grainstones of the flanking facies) suggest that the micrite in the mound was autochthonous and implies the presence of an energy

The ammonoids from the Three Forks Shale (Late Devonian of Montana

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D. Korn

2006-08-01

Full Text Available The ammonoid fauna from the Late Devonian Three Forks Shale of Montana is revised. Six taxa were recognised, which belong to the genera Tornoceras, Pernoceras, Raymondiceras, Platyclymenia, Pleuroclymenia, and Carinoclymenia. The ammonoid assemblage suggests a stratigraphic position within the middle Famennian, most probably the Platyclymenia annulata Zone. The ammonoids display extreme septal crowding in intermediate as well as adult growth stages, which can be regarded as evidence for instable palaeoecological conditions during lifetime of the animals. Die Ammonoideenfauna aus dem oberdevonischen Three Forks Shale von Montana wird revidiert. Sechs Taxa werden unterschieden; sie gehören zu den Gattungen Tornoceras, Pernoceras, Raymondiceras, Platyclymenia, Pleuroclymenia und Carinoclymenia. Die Ammonoideen-Vergesellschaftung spricht für eine stratigraphische Position im mittleren Famennium, wahrscheinlich in der Platyclymenia annulata Zone. Die Ammonoideen zeigen auffällige Drängung der Septen in intermediären und adulten Wachstumsstadien, die als Hinweis auf instabile Lebensbedingungen für die Tiere gewertet werden kann. doi:10.1002/mmng.200600008

A new elasmobranch Karksiodus mirus gen. et sp. nov. from the Burtnieki Regional Stage, Middle Devonian of Estonia

OpenAIRE

Alexander Ivanov; Tiiu Märss; Anne Kleesment

2011-01-01

Teeth of a new elasmobranch Karksiodus mirus gen. et sp. nov. were discovered on two levels in the sandstones of the Karksi outcrop (South Estonia), corresponding to the Härma Beds, lower part of the Burtnieki Regional Stage (Givetian, Middle Devonian). These teeth differ from all known Palaeozoic elasmobranch teeth in the presence of a unique wide transversal tube-shaped basal canal, in very fine and dense striation of cusps and in an arched base without well-developed extensions. The order ...

Provenance and paleogeography of the Devonian Durazno Group, southern Parana Basin in Uruguay

Science.gov (United States)

Uriz, N. J.; Cingolani, C. A.; Basei, M. A. S.; Blanco, G.; Abre, P.; Portillo, N. S.; Siccardi, A.

2016-03-01

A succession of Devonian cover rocks occurs in outcrop and in the subsurface of central-northern Uruguay where they were deposited in an intracratonic basin. This Durazno Group comprises three distinct stratigraphic units, namely the Cerrezuelo, Cordobés and La Paloma formations. The Durazno Group does not exceed 300 m of average thickness and preserves a transgressive-regressive cycle within a shallow-marine siliciclastic shelf platform, and is characterized by an assemblage of invertebrate fossils of Malvinokaffric affinity especially within the Lower Devonian Cordobés shales. The sedimentary provenance of the Durazno Group was determined using petrography, geochemistry, and morphological studies of detrital zircons as well as their U-Pb ages. Sandstone petrography of Cerrezuelo and La Paloma sequences shows that they have a dominantly quartz-feldspathic composition with a minor contribution of other minerals. Whole-rock geochemical data indicate that alteration was strong in each of the three formations studied; chondritic-normalized REE patterns essentially parallel to PAAS, the presence of a negative Eu-anomaly, and Th/Sc and La/Hf ratios point to an average source composition similar to UCC or slightly more felsic. Within the Cerrezuelo Formation, recycling of older volcano-metasedimentary sources is interpreted from Zr/Sc ratios and high Hf, Zr, and REE concentrations. U-Pb detrital zircon age populations of the Cerrezuelo and La Paloma formations indicate that the principal source terranes are of Neoproterozoic age, but include also minor populations derived from Mesoproterozoic and Archean-Paleoproterozoic rocks. A provenance from the Cuchilla Dionisio-Dom Feliciano, Nico Pérez and Piedra Alta terranes of Uruguay and southern Brazil is likely. This study establishes an intracratonic extensional tectonic setting during Durazno time. Considering provenance age sources, regional paleocurrent distributions and the established orogenic history recorded in SW

Paleozoic stratigraphy of two areas in southwestern Indiana

International Nuclear Information System (INIS)

Droste, J.B.

1976-09-01

Two areas recommended for evaluation as solid waste disposal sites lie along the strike of Paleozoic rocks in southwestern Indiana. Thin Pennsylvanian rocks and rocks of the upper Mississippian are at the bedrock surface in maturely dissected uplands in both areas. The gross subsurface stratigraphy beneath both areas is the same, but facies and thickness variation in some of the subsurface Paleozoic units provide for some minor differences between the areas. Thick middle Mississippi carbonates grade downward into clastics of lower Mississippian (Borden Group) and upper Devonian (New Albany Shale) rocks. Middle Devonian and Silurian rocks are dominated by carbonate lithologies. Upper Ordovician (Maquoketa Group) overly carbonates of middle Ordovician age. Thick siltstone and shale of the Borden Group-New Albany Shale zone and Maquoketa Group rocks should be suitable for repository development

Climate instability and tipping points in the Late Devonian: Detection of the Hangenberg Event in an open oceanic island arc in the Central Asian Orogenic Belt

Czech Academy of Sciences Publication Activity Database

Carmichael, A.; Waters, J. A.; Batchelor, C. J.; Coleman, D. M.; Suttner, T. J.; Kido, E.; Moore, L. M.; Chadimová, Leona

2016-01-01

Roč. 32, 1 April (2016), s. 213-231 ISSN 1342-937X Institutional support: RVO:67985831 Keywords : Central Asian Orogenic Belt * chemostratigraphy * Devonian-Carboniferous * Hangenberg Event * West Junggar Subject RIV: DB - Geology ; Mineralogy Impact factor: 6.959, year: 2016

A review of the organic geochemistry of shales and possible interactions between the organic matter of shales and radionuclides

International Nuclear Information System (INIS)

Ho, P.C.

1990-01-01

Shale formations have been suggested as potential host rocks for high level nuclear waste repositories. Several studies have demonstrated the interactions of nuclides with organic compounds found in shales. In order to understand the possibility of interaction between organic components of shales and trace elements, literature on the identification of organic compounds from various shales of the continental United States and evidences of interactions have been reviewed first. The Green River Formation of the Cenozoic era is the most studied shale followed by the Pierre Shale of the Mesozoic era and the Devonian Black Shale of the Paleozoic era. Organic compounds that have been identified from these shales are mainly hydrocarbons and carboxylates along with small amounts of other compounds. These organic compounds, however, constitute only a small fraction of the organic matter in shales; the majority of the organic compounds in shales are still unidentified. Interaction between organics and trace elements are found mostly due to the formation of complexes between carboxylates of shales and the elements. (orig.)

The organic carbon isotope of lacustrine sediments of the Upper Shahejie formation in Huanghua Depression: a record of sedimentary environment and productivity of an ancient lake

International Nuclear Information System (INIS)

Fei, Weiwei; Huang, Xiaoyan; Dai, Na; Zhong, Ningning

2013-01-01

Huanghua depression was one of the largest Paleogene rift lakes in Bohai Bay basin, eastern China. The lake had broad area and deep water in the period of development peak—Oligocene 36~38Ma B.C., when organic-rich mudstones of upper Shahejie Formation formed. Twenty eight distal lake facie samples of the upper Shahejie Formation from Well GS35 were analyzed for organic carbon isotope, TOC, hydrogen index and trace elements in order to investigate the controls of organic carbon accumulation in the lake. The results show that lacustrine mudstones in the middile member of the upper Shahejie Formation have a heavy organic carbon isotope (-28.6 ‰ to -21.1 ‰) and a intense fractionation which is more than 7‰. In addition, it shows a good positive correlation with the total organic carbon (TOC) (Figure 1). Organic petrographic and organic geochemical analysis indicate that the biological inputs of the mudstone is dominated by algae and other aquatic organisms, and a low content of gammacerane prove the water is freshwater-brackish, so terrigenous organic matter and water salinity have little effect on its organic carbon isotope composition (δ"1"3C_o_r_g). It has well been documented that the climate in Bohai Bay basin was warm and humid during deposition of the upper Shahejie Formation, and the temperature did not change dramatically at that time (TaoZ et al., 2005). Ultimately, the heavy carbon isotope values of lacustrine organic matter may indicate the high productivity of ancient lakes. The good correlation between total organic carbon (TOC) and organic carbon isotope (δ"1"3C_o_r_g) as well as the widely existed organic-rich lamellae of the mudstone are the strong evidence for high paleoproductivity of the upper Shahejie Formation in Huanghua Depression during the deposition period. (1) Organic-rich lamellae of the mudstone formed in anoxia and stable environment have been recognized as the best evidence of high paleoproductivity. The presence of organic

Paleomagnetism of Devonian dykes in the northern Kola Peninsula and its bearing on the apparent polar wander path of Baltica in the Precambrian

Science.gov (United States)

Veselovskiy, Roman V.; Bazhenov, Mikhail L.; Arzamastsev, Andrey A.

2016-04-01

Mafic dykes and large alkaline and carbonatite intrusions of Middle-Late Devonian age are widespread on the Kola Peninsula in NE Fennoscandia. These magmatic rocks are well characterized with petrographic, geochemical and geochronological data but no paleomagnetic results have been reported yet. We studied dolerite dykes from the northern part of the Peninsula and isolated three paleomagnetic components in these rocks. A low-temperature component is aligned along the present-day field, while a major constituent of natural remanent magnetization is an intermediate-temperature component (Decl. = 79.6°, Inc. = 78.5°, α95 = 5,9°, N = 17 sites) that is present in most Devonian dykes but is found in some baked metamorphic rocks and Proterozoic dykes too. Finally, a primary Devonian component could be reliably isolated from two dykes only. Rock-magnetic studies point to presumably primary low-Ti titanomagnetite and/or pure magnetite as the main remanence carriers but also reveal alteration of the primary minerals and the formation of new magnetic phases. The directions of a major component differ from the Middle Paleozoic reference data for Baltica but closely match those for the 190 ± 10 Ma interval recalculated from the apparent polar wander path of the craton. We assume that this Early Jurassic component is a low-temperature overprint of chemical origin. The main impact of the new results is not to mid-Paleozoic or Early Mesozoic times but to much older epochs. Analysis of paleomagnetic data shows that the directionally similar remanences are present in objects with the ages ranging from 500 Ma to 2 Ga over entire Fennoscandia. Hence we argue that an Early Jurassic remagnetization is of regional extent but cannot link it to a certain process and a certain tectonic event. If true, this hypothesis necessitates a major revision of the APWP for Baltica over a wide time interval.

Temporal variability in terrestrially-derived sources of particulate organic carbon in the lower Mississippi River and its upper tributaries

Science.gov (United States)

Bianchi, Thomas S.; Wysocki, Laura A.; Stewart, Mike; Filley, Timothy R.; McKee, Brent A.

2007-09-01

In this study, we examined the temporal changes of terrestrially-derived particulate organic carbon (POC) in the lower Mississippi River (MR) and in a very limited account, the upper tributaries (Upper MR, Ohio River, and Missouri River). We used for the first time a combination of lignin-phenols, bulk stable carbon isotopes, and compound-specific isotope analyses (CSIA) to examine POC in the lower MR and upper tributaries. A lack of correlation between POC and lignin phenol abundances ( Λ8) was likely due to dilution effects from autochthonous production in the river, which has been shown to be considerably higher than previously expected. The range of δ 13C values for p-hydroxycinnamic and ferulic acids in POC in the lower river do support that POM in the lower river does have a significant component of C 4 in addition to C 3 source materials. A strong correlation between δ 13C values of p-hydroxycinnamic, ferulic, and vanillyl phenols suggests a consistent input of C 3 and C 4 carbon to POC lignin while a lack of correlation between these same phenols and POC bulk δ 13C further indicates the considerable role of autochthonous carbon in the lower MR POC budget. Our estimates indicate an annual flux of POC of 9.3 × 10 8 kg y -1 to the Gulf of Mexico. Total lignin fluxes, based on Λ8 values of POC, were estimated to be 1.2 × 10 5 kg y -1. If we include the total dissolved organic carbon (DOC) flux (3.1 × 10 9 kg y -1) reported by [Bianchi T. S., Filley T., Dria K. and Hatcher, P. (2004) Temporal variability in sources of dissolved organic carbon in the lower Mississippi River. Geochim. Cosmochim. Acta68, 959-967.], we get a total organic carbon flux of 4.0 × 10 9 kg y -1. This represents 0.82% of the annual total organic carbon supplied to the oceans by rivers (4.9 × 10 11 kg).

Timing training in three children with diplegic cerebral palsy: Short- and long-term effects on upper-limb movement organization and functioning

Directory of Open Access Journals (Sweden)

Anna-Maria eJohansson

2014-03-01

Full Text Available Despite the great need of interventions to maintain and improve motor functions in children with diplegic cerebral palsy (DCP, scientific evaluations of existing training methods are rare. This study aimed to explore individual effects of synchronized metronome training (SMT on motor timing, spatio-temporal movement organization, and subjective experiences of changes in upper-limb functions in three children with DCP. All children participated in an individualized 4-week/12 session SMT training regime. Measurements before training (Pre, after training (Post1 and at 6 months post completed training (Post2 were made by the applied SMT training equipment, optoelectronic registrations of goal-directed upper-limb movements, and a questionnaire assessing subjective experiences of changes in upper-limb functions and usability. In general, the training regime was shown to have little effect on motor timing. However, some positive changes in spatio-temporal movement organization were found. Two children also reported substantial long-lasting positive changes in subjective experiences of hand/arm functionality in terms of increased movement control and reduced muscle tone. For these children, parallel kinematic findings also indicated smoother and faster movement trajectories that remained at Post2. Although highly individualized, the shown improvements in upper-limb kinematics and subjective experiences of improved functionality of the hands/arms for two of the cases warrant further explorations of SMT outcomes in children with DCP.

Late Paleozoic SEDEX deposits in South China formed in a carbonate platform at the northern margin of Gondwana

Science.gov (United States)

Qiu, Wenhong Johnson; Zhou, Mei-Fu; Liu, Zerui Ray

2018-05-01

SEDEX sulfide deposits hosted in black shale and carbonate are common in the South China Block. The Dajiangping pyrite deposit is the largest of these deposits and is made up of stratiform orebodies hosted in black shales. Sandstone interlayered with stratiform orebodies contains detrital zircon grains with the youngest ages of 429 Ma. Pyrite from the orebodies has a Re-Os isochron age of 389 ± 62 Ma, indicative of formation of the hosting strata and syngenetic pyrite ores in the mid-late Devonian. The hosting strata is a transgression sequence in a passive margin and composed of carbonaceous limestone in the lower part and black shales in the upper part. The ore-hosting black shales have high TOC (total organic carbon), Mo, As, Pb, Zn and Cd, indicating an anoxic-euxinic deep basin origin. The high redox proxies, V/(V + Ni) > 0.6 and V/Cr > 1, and the positive correlations of TOC with Mo and V in black shales are also consistent with an anoxic depositional environment. The Dajiangping deposit is located close to the NE-trending Wuchuan-Sihui fault, which was active during the Devonian. The mid-late Devonian mineralization age and the anoxic-euxinic deep basinal condition of this deposit thus imply that the formation of this deposit was causally linked to hydrothermal fluid exhalation in an anoxic fault-bounded basin that developed in a carbonate platform of the South China Block. The regional distribution of many Devonian, stratiform, carbonaceous sediment-hosted sulfide deposits along the NE-trending fault-bounded basins in South China, similar to the Dajiangping deposit, indicates that these deposits formed at a basin developed in the passive margin setting of the South China Block during the Devonian. This environment was caused by the break-up and northward migration of the South China Block from Gandwana.

A new elasmobranch Karksiodus mirus gen. et sp. nov. from the Burtnieki Regional Stage, Middle Devonian of Estonia

Directory of Open Access Journals (Sweden)

Alexander Ivanov

2011-03-01

Full Text Available Teeth of a new elasmobranch Karksiodus mirus gen. et sp. nov. were discovered on two levels in the sandstones of the Karksi outcrop (South Estonia, corresponding to the Härma Beds, lower part of the Burtnieki Regional Stage (Givetian, Middle Devonian. These teeth differ from all known Palaeozoic elasmobranch teeth in the presence of a unique wide transversal tube-shaped basal canal, in very fine and dense striation of cusps and in an arched base without well-developed extensions. The order and family of this taxon are notspecified.

Devonian conodonts from the Foča–Prača Paleozoic complex (Durmitor Nappe, southeastern Bosnia and Herzegovina

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Bogdan Jurkovšek

2011-06-01

Full Text Available Conodont study of the Crna Rijeka borehole CR-17, positioned in the frontal part of the Durmitor Nappe (Foča – Prača Paleozoic complex, SE Bosnia and Herzegovina is presented. The obtained fauna indicates an Early-Middle Devonian age and due to poor preservation an identification at a generic level is possible only. The recovered conodont elements have a high Color Alteration Index (CAI = 6,5–7 indicating a degree of metamorphism corresponding to a temperature interval from 440 °C to 720 °C.

Organic geochemical characterization of potential hydrocarbon source rocks in the upper Benue Trough

International Nuclear Information System (INIS)

Obaje, N. G.; Pearson, M. J.; Suh, C. E.; Dada, S. S.

1999-01-01

The Upper Benue Trough of Nigeria is the northeastern most portion of the Benue rift structure that extends from the northern limit of the Niger Delta in the south to the southern limit of the Chad basin int he northeast. this portion of the trough is made up of two arms: the Gongola Arm and the Yola Arm. Stratigraphic sequence in the Gongola Arm comprises the continental Albian Bima Sandstone, the transitional Cenomanian Yolde Formation and the marine Turonian - Santonian Gongila, Pindiga, and Fika Formations. Overlying these are the continental Campane - Maastrichtian Gombe Sandstone and the Tertiary Kerri - Kerri Formation. In the Yola Arm, the Turonian - Santonian sequence is replaced by the equally marine Dukul, Jessu, Sekuliye Formations, Numanha Shale, and the Lamja Sandstone. Organic geochemical studies have been carried on outcrop sample form the Gongila, Pindiga, Dukul Formations, the Fika shale and the shaly units of the Gombe Sandstone, with the aim of assessing their source rock potential. Gas Chromatography (GC), Gas Chromatography - Mass Spectrometry (C - MS), and Rock Eval Pyrolysis were the major organic geochemical tools employed. Biomaker hydrocarbon signatures obtained from the GC - MS and the Rock Eval Pyrolysis results indicate that all he formations studied, except the Dukul formation, are immature and are all lean in organic matter

Frasnian

OpenAIRE

Coen-Aubert, M.; Boulvain, Frédéric

2006-01-01

The name Frasnian, which comes from the locality of Frasnes near Couvin in Belgium, was introduced by Gosselet in 1879 and was formally retained for the lower stage of the Upper Devonian by the Subcommission on Devonian Stratigraphy in 1981. The modern definition of the Frasnian is based on conodonts and the historical background of the stage is developed in detail herein. Data about the lithostratigraphy, sedimentology, biostratigraphy, chronostratigraphy and absolute age of the Frasnian can...

GIVETIAN–FRASNIAN BOUNDARY CONODONTS FROM KERMAN PROVINCE, CENTRAL IRAN

OpenAIRE

GHOLAMALIAN, HOSSEIN; HAIRAPETIAN, VACHIK; BARFEHEI, NAHID; MANGELIAN, SOHEYLA; FARIDI, PARVANEH

2013-01-01

The Middle - Late Devonian boundary is investigated based on twenty-two conodont species and subspecies from three sections in the north and west of Kerman, southeastern central Iran. Upper Givetian - lower Frasnian carbonates of the basal part of the Bahram Formation transgressively overlie the sandstone beds of the top of (?) Early - Middle Devonian Padeha Formation. These massive skeletal limestones encompass the G-F boundary. The base of Frasnian is identified by the appearance of early f...

Prospects for an upper Givetian substage

Directory of Open Access Journals (Sweden)

Z. S. Aboussalam

2001-01-01

Full Text Available New ammonoid and conodont data from Germany, the Montagne Noire (France and southeastern Morocco document a complex sequence of sedimentary events and faunal changes within an extended Givetian (late Middle Devonian Taghanic Event Interval or Taghanic Biocrisis. Direct association of supposed typical middle Givetian ammonoids, trilobites and corals with upper Givetian marker taxa such as pharciceratids have been found, for example, in Moroccan and French time equivalents of the New York Upper Tully Limestone. The initial and eustatic Taghanic Onlap level is not known to be characterized by the first appearance of any widespread index conodont, goniatite or other taxon. A future upper Givetian substage, therefore, might be based either on the entry of Ozarkodina semialternans or on the first appearance of Schmidtognathus hermanni. The semialternans Zone correlates with a third sedimentary cycle within the Tully Limestone and with the spread of the first Pharciceratidae. Eobeloceratidae (Mzerrebites juvenocostatus and Archoceratidae n. fam. (Atlantoceras. The (Lower hermanni Zone is marked by a post-event transgression which led to a significant conodont radiation and to a further diversification of Pharciceratidae and Eobeloceratidae (Mz. erraticus. Neue Ammonoideen- und Conodonten-Daten aus Deutschland, Frankreich (Montagne Noire und aus Südost-Marokko belegen eine komplexe Abfolge sedimentärer Ereignisse und von Faunenwechseln in einem längerfristigen Taghanic-Event-Intervall bzw. einer Taghanic-Biokrise des Givetiums (oberes Mittel-Devon. Direkte Vergesellschaftungen von Ammonoideen, Trilobiten und Korallen, die früher als typische Mittel-Givetium-Formen angesehen wurden, mit Leitformen des Ober-Givetiums (z. B. Pharciceraten konnten in Marokko und Frankreich in Zeitequivalenten des Oberen Tully-Kalkes von New York nachgewiesen werden. Der initiale und eustatisch bedingte Taghanic Onlap ist bisher nicht durch das Einsetzen eines weit

Devonian alkaline magmatism in the northern North China Craton: Geochemistry, SHRIMP zircon U-Pb geochronology and Sr-Nd-Hf isotopes

Directory of Open Access Journals (Sweden)

Dingling Huang

2017-01-01

Full Text Available The Wulanhada pluton is among the rare suite of Devonian alkaline plutons occurring along the northern margin of the North China Craton (NCC. The intrusion is mainly composed of quartz-monzonite. Here we report zircon SHRIMP U-Pb data from this intrusion which shows emplacement age of ca. 381.5 Ma. The rock is metaluminous with high (Na2O + K2O values ranging from 8.46 to 9.66 wt.%. The REE patterns of the rocks do not show any Eu anomaly whereas the primitive-mantle-normalized spider diagram shows strong positive Sr and Ba anomalies. The Wulanhada rocks exhibit high initial values of (87Sr/86Srt = 0.70762–0.70809, low ɛNd(t = −12.76 to −12.15 values and negative values of ɛHf(t = −23.49 to −17.02 with small variations in (176Hf/177Hft (0.281873–0.282049. These geochemical features and quantitative isotopic modeling results suggest that the rocks might have been formed through the partial melting of Neoarchean basic rocks in the lower crust of the NCC. The Wulanhada rocks, together with the Devonian alkaline rocks and mafic-ultramafic complex from neighboring regions, constitute a post-collisional magmatic belt along the northern NCC.

Studies on improvement of diagnostic ability of computed tomography (CT) in the parenchymatous organs in the upper abdomen, 1. Study on the upper abdominal compression method

Energy Technology Data Exchange (ETDEWEB)

Kawata, Ryo [Gifu Univ. (Japan). Faculty of Medicine

1982-07-01

1) The upper abdominal compression method was easily applicable for CT examination in practically all the patients. It gave no harm and considerably improved CT diagnosis. 2) The materials used for compression were foamed polystyrene, the Mix-Dp and a water bag. When CT examination was performed to diagnose such lesions as a circumscribed tumor, compression with the Mix-Dp was most useful, and when it was performed for screening examination of upper abdominal diseases, compression with a water bag was most effective. 3) Improvement in contour-depicting ability of CT by the compression method was most marked at the body of the pancreas, followed by the head of the pancreas and the posterior surface of the left lobe of the liver. Slight improvement was seen also at the tail of the pancreas and the left adrenal gland. 4) Improvement in organ-depicting ability of CT by the compression method was estimated by a 4-category classification method. It was found that the improvement was most marked at the body and the head of the pancreas. Considerable improvement was observed also at the left lobe of the liver and the both adrenal glands. Little improvement was obtained at the spleen. When contrast enhancement was combined with the compression method, improvement at such organs which were liable to be enhanced, as the liver and the adrenal glands, was promoted, while the organ-depicting ability was decreased at the pancreas. 5) By comparing the CT image under compression with that without compression, continuous infiltrations of gastric cancer into the body and the tail of the pancreas in 2 cases and a retroperitoneal infiltration of pancreatic tumor in 1 case were diagnosed preoperatively.

The Late Devonian Frasnian-Famennian (F/F) biotic crisis: Insights from δ13C carb, δ13C org and 87Sr / 86Sr isotopic systematics

Science.gov (United States)

Chen, Daizhao; Qing, Hairuo; Li, Renwei

2005-06-01

A severe biotic crisis occurred during the Late Devonian Frasnian-Famennian (F/F) transition (± 367 Myr). Here we present δ13C carb, δ13C org and 87Sr / 86Sr isotopic systematics, from identical samples of two sections across F/F boundary in South China, which directly demonstrate large and frequent climatic fluctuations (˜200 kyr) from warming to cooling during the F/F transition. These climate fluctuations are interpreted to have been induced initially by increased volcanic outgassing, and subsequent enhanced chemical weathering linked to the rapid expansion of vascular plants on land, which would have increased riverine delivery to oceans and primary bioproductivity, and subsequent burial of organic matter, thereby resulting in climate cooling. Such large and frequent climatic fluctuations, together with volcanic-induced increases in nutrient (e.g., biolimiting Fe), toxin (sulfide) and anoxic water supply, and subsequent enhanced riverine fluxes and microbial bloom, were likely responsible for the stepwise faunal demise of F/F biotic crisis.

Climatic-oceanic forcing on the organic accumulation across the shelf during the Early Cambrian (Age 2 through 3) in the mid-upper Yangtze Block, NE Guizhou, South China

Science.gov (United States)

Yeasmin, Rumana; Chen, Daizhao; Fu, Yong; Wang, Jianguo; Guo, Zenghui; Guo, Chuan

2017-02-01

The organic-rich sediments were widely deposited over the entire Yangtze Block during the Early Cambrian (late Nemakit-Daldynian to Botomian). In the mid-upper Yangtze region, northeastern Guizhou, South China, they comprise, in ascending order, the Niutitang, Jiumenchong and lower Bianmachong formations which are dominated by black shales except the middle one characterized by interbedded shales-limestones. Three third-order depositional sequences are identified in the two studied sections located on the upper slope to basin of the open shelf. The organic-rich sediments were mostly deposited notably during transgressions on the shallower upper slope-margin (TOC up to 25 wt.%) where they are characterized by co-increases in C, P, Fe, and Ba concentrations, indicating the highest organic productivity and coupled C, P and Fe cycling there. In contrast, in the shelf basin, the concomitant organic-rich sediments yield lower organic (TOC Block within the north mid-low-latitude trade-wind zone during deposition (the Early Cambrian). As such, enhanced offshore currents driven by the trade winds could have further induced the upwelling of nutrient-rich deep waters along the shelf during the transgressions, although tended to wane onwards, leading to the tempo-spatial heterogeneities in organic production and redox state across the shelf sea.

Lithosphere evolution during the pre devonian of Uruguay: Prevalence of strike slip faults

International Nuclear Information System (INIS)

Bossi, J.

2010-01-01

The available data about mega shear zones were analyzed. Also the geo chronological trusty data about pre devonian rocks from Uruguay were overlapped. Emphasizing in the basic rocks, four tecto no-stratigraphy c terranes might be recognized. The approximate age of those rocks is known as well as the displacement trend. It can be concluded that the transmazonian age Piedra Alta Terrane (transmazonian age 2000 ± 100 My) is the most ancient block followed by the Tandilla Terrane (ages 2200 ± 100 My) which was joined through 1700 Ma. The Nico Perez Terrane displaced itself towards South generating the continental N10W mega shear fault Sarandi del Yi- Piriapolis towards 1250 My. Finally, the Arachania called continent made tangential collision from SE towards 525 Ma generating the ultramylonites band of the Sierra Ballena share zone. Each one of these terranes have totally different stratigraphy and lithological associations, and the chronological ages did not agree with the arrival of each one of the identified terranes

Two hundred years of palaeontological discovery: Review of research on the Early to Middle Devonian Bokkeveld Group (Cape Supergroup) of South Africa

Science.gov (United States)

Penn-Clarke, C. R.; Rubidge, B. S.; Jinnah, Z. A.

2018-01-01

Documentation of the palaeontological heritage of the Early to Middle Devonian Bokkeveld Group of South Africa has been recorded as far back as the early nineteenth century with the arrival of the first European settlers, merchants and explorers to the Cape region. Anecdotal evidence suggests that indigenous peoples had knowledge of fossils in the Bokkeveld Group from as early as the Middle-to-Late Stone Age. Within the first hundred years of the expansion of the Cape Colony the first geological maps of the Bokkeveld Group were produced alongside the first description of fossils as well as their Devonian age and marine origin. These early investigations provided a foundation for establishing faunal endemism common to South Africa, South America and the Falkland Islands. During the early twentieth century considerable progress was made in the description of fossil fauna of the Bokkeveld Group, most notably of invertebrates and plants. This research demonstrated that invertebrate fossils from the Bokkeveld Group, as well as those from time equivalents in South America and the Falkland Islands, were distinct from the Devonian Period elsewhere (e.g. Europe and North America). The role of fossils from the Bokkeveld Group proved critical in the formal designation and delineation of a broad region of endemism, the Malvinokaffric Realm that persisted at high subpolar-to-polar palaeolatitudes in southwestern Gondwana and extended from South Africa, Bolivia, Brazil, Argentina, Antarctica and the Falkland Islands with possible elements in Guinea-Bissau, Senegal and Ghana during the Emsian-Eifelian Stages. In the latter half of the twentieth century developments in understanding the sedimentology and stratigraphy of the Bokkeveld Group lead to the premise that the succession accumulated in a storm-and-wave dominated deltaic palaeoenvironment, and enabled inferences on the palaeoecology of the fossil taxa. During this period detailed revisions of numerous invertebrate and plant

The Late Devonian Gogo Formation Lägerstatte of Western Australia: Exceptional Early Vertebrate Preservation and Diversity

Science.gov (United States)

Long, John A.; Trinajstic, Kate

2010-05-01

The Gogo Formation of Western Australia preserves a unique Late Devonian (Frasnian) reef fauna. The exceptional three-dimensional preservation of macrofossils combined with unprecedented soft-tissue preservation (including muscle bundles, nerve cells, and umbilical structures) has yielded a particularly rich assemblage with almost 50 species of fishes described. The most significant discoveries have contributed to resolving placoderm phylogeny and elucidating their reproductive physiology. Specifically, these discoveries have produced data on the oldest known vertebrate embryos; the anatomy of the primitive actinopterygian neurocranium and phylogeny of the earliest actinopterygians; the histology, radiation, and plasticity of dipnoan (lungfish) dental and cranial structures; the anatomy and functional morphology of the extinct onychodonts; and the anatomy of the primitive tetrapodomorph head and pectoral fin.

Uranium project GEO 2 attachment: cronostratigraphy aplied to Uranium research; Proyecto Uranio anexo GEO 2: cronoestratigrafia aplicada a la investigacion de Uranio

Energy Technology Data Exchange (ETDEWEB)

NONE

1983-07-01

In the article, different sources of information about Uranium stratigraphy from Uruguay have been reviewed. Some results have been presented in Upper Cambrian period and Precambrian era, specially Devonian, Carboniferous and Silurian period.

Uranium project GEO 2 attachment: cronostratigraphy aplied to Uranium research

International Nuclear Information System (INIS)

1983-01-01

In the article, different sources of information about Uranium stratigraphy from Uruguay have been reviewed. Some results have been presented in Upper Cambrian period and Precambrian era, specially Devonian, Carboniferous and Silurian period

CT arteriography of the upper abdomen

Energy Technology Data Exchange (ETDEWEB)

Hasuo, K; Matsuura, K; Baba, H; Numaguchi, Y; Komaki, S [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine

1980-04-01

The technique of CT arteriography was introduced, and CT images of the upper abdomen were explained. Very clear enhancement of parenchyma and vessels (especially portal vein) of the object organs could be obtained by CT arteriography of the upper abdomen, anatomical structures of organs were identified more easily by CT arteriography than by conventional CT, and the amount of information obtained was increased by using CT arteriography. However, the indication of CT arteriography must be limited, because of its complexity that CT arteriography is performed after angiography and involves the invasion of patients' bodies. As described in many reports, CT arteriography is useful for malignant tumors of the liver, and it is worthwhile, especially when surgery for hepatocellular carcinoma is considered. CT arteriography for organs except the liver has not been discussed sufficiently. Therefore, an application of this method for other organs must be decided after consideration of the balance of the amount of information obtained by CT arteriography with invasion to patients.

Mid-upper-arm-circumference and mid-upper-arm circumference z-score

DEFF Research Database (Denmark)

Rasmussen, J; Andersen, A; Fisker, A B

2012-01-01

Mid-upper-arm circumference (MUAC) is a simple method of assessing nutritional status in children above 6 months of age. In 2007 World Health Organization (WHO) introduced a MUAC z-score for children above 3 months of age. We evaluated whether MUAC or MUAC z-score had the best ability to identify...

Lower Paleozoic carbonate rocks of Baird Mountains Quadrangle, Alaska

Energy Technology Data Exchange (ETDEWEB)

Dumoulin, J.A.; Harris, A.G.

1985-04-01

Lower Paleozoic carbonate rocks in the Baird Mountains quadrangle form a relatively thin (about 550 m), chiefly shallow-water succession that has been imbricately thrust and metamorphosed to lower greenschist facies. Middle and Upper Cambrian rocks - the first reported from the western Brooks Range - occur in the northeastern quarter of the quadrangle, south of Angayukaqsraq (formerly Hub) Mountain. They consist of marble grading upward into thin-bedded marble/dolostone couplets and contain pelagiellid mollusks, acetretid brachiopods, and agnostid trilobites. Sedimentologic features and the Pelagiellas indicate a shallow-water depositional environment. Overlying these rocks are Lower and Middle Ordovician marble and phyllite containing graptolites and conodonts of midshelf to basinal aspect. Upper Ordovician rocks in this area are bioturbated to laminated dolostone containing warm, shallow-water conodonts. In the Omar and Squirrel Rivers areas to the west, the Lower Ordovician carbonate rocks show striking differences in lithofacies, biofacies, and thickness. Here they are mainly dolostone with locally well-developed fenestral fabric and evaporite molds, and bioturbated to laminated orange- and gray-weathering dolomitic marble. Upper Silurian dolostone, found near Angayukaqsraq Mountain and on the central Squirrel River, contains locally abundant corals and stronmatoporoids. Devonian carbonate rocks are widely distributed in the Baird Mountains quadrangle; at least two distinct sequences have been identified. In the Omar area, Lower and Middle Devonian dolostone and marble are locally cherty and rich in megafossils. In the north-central (Nakolik River) area, Middle and Upper Devonian marble is interlayered with planar to cross-laminated quartz-carbonate metasandstone and phyllite.

Aquifer Characteristics Data Report for the Weldon Spring Site chemical plant/raffinate pits and vicinity properties for the Weldon Spring Site Remedial Action Project, Weldon Spring, Missouri

International Nuclear Information System (INIS)

1990-11-01

This report describes the procedures and methods used, and presents the results of physical testing performed, to characterize the hydraulic properties of the shallow Mississippian-Devonian aquifer beneath the Weldon Spring chemical plant, raffinate pits, and vicinity properties. The aquifer of concern is composed of saturated rocks of the Burlington-Keokuk Limestone which constitutes the upper portion of the Mississippian-Devonian aquifer. This aquifer is a heterogeneous anisotropic medium which can be described in terms of diffuse Darcian flow overlain by high porosity discrete flow zones and conduits. Average hydraulic conductivity for all wells tested is 9.6E-02 meters/day (3.1E-01 feet/day). High hydraulic conductivity values are representative of discrete flow in the fractured and weathered zones in the upper Burlington-Keokuk Limestone. They indicate heterogeneities within the Mississippian-Devonian aquifer. Aquifer heterogeneity in the horizontal plane is believed to be randomly distributed and is a function of fracture spacing, solution voids, and preglacial weathering phenomena. Relatively high hydraulic conductivities in deeper portions of the aquifer are though to be due to the presence of widely spaced fractures. 44 refs., 27 figs., 9 tabs

New Insights in the Ontogeny and Taphonomy of the Devonian Acanthodian Triazeugacanthus affinis From the Miguasha Fossil-Lagerstätte, Eastern Canada

Directory of Open Access Journals (Sweden)

Marion Chevrinais

2015-12-01

Full Text Available Progressive biomineralization of a skeleton occurs during ontogeny in most animals. In fishes, larvae are poorly mineralized, whereas juveniles and adults display a progressively more biomineralized skeleton. Fossil remains primarily consist of adult specimens because the fossilization of poorly-mineralized larvae and juveniles necessitates exceptional conditions. The Miguasha Fossil-Lagerstätte is renowned for its Late Devonian vertebrate fauna, revealing the exceptional preservation of fossilized ontogenies for 14 of the 20 fish species from this locality. The mineralization of anatomical structures of the acanthodian Triazeugacanthus affinis from Miguasha are compared among larval, juvenile and adult specimens using Energy Dispersive X-ray Spectrometry. Chemical composition of anatomical structures of Triazeugacanthus reveals differences between cartilage and bone. Although the histology and anatomy is well-preserved, Fourier transform infrared spectrometry shows that the original chemical composition of bone is altered by diagenesis; the mineral phase of the bone (i.e., hydroxyapatite is modified chemically to form more stable carbonate-fluorapatite. Fluorination occurring in mineralized skeletal structures of adult Triazeugacanthus is indicative of exchanges between groundwater and skeleton at burial, whereas the preservation of larval soft tissues is likely owing to a rapid burial under anoxic conditions. The exceptional state of preservation of a fossilized ontogeny allowed us to characterize chemically the progressive mineralization of the skeleton in a Devonian early vertebrate.

A new assessment of the Late Devonian antiarchan fish Bothriolepis leptocheira from South Timan (Russia) and the biotic crisis near the Frasnian–Famennian boundary

OpenAIRE

Ervīns Lukševičs; Pavel Beznosov; Valdemārs Stūris

2017-01-01

The species of the Late Devonian, earliest Famennian placoderm fish Bothriolepis jeremejevi has been downranked to subspecies Bothriolepis leptocheira jeremejevi comb. nov. in a result of detailed morphological studies of the type specimens and abundant new material from the type locality of the Sosnogorsk Formation, South Timan, Komi Republic, Russia. This taxon closely resembles Bothriolepis leptocheira leptocheira from Scotland, B. leptocheira curonica from Latvia, and B. leptocheira ssp. ...

CONSIDERATIONS ON ANATOMY AND PHYSIOLOGY OF LYMPH VESSELS OF UPPER AERO DIGESTIVE ORGANS AND CERVICAL SATELLITE LYMPH NODE GROUP.

Science.gov (United States)

Ciupilan, Corina; Stan, C I

2016-01-01

The almost constant local regional development of the cancers of upper aero digestive organs requires the same special attention to cervical lymph node metastases, as well as to the primary neoplastic burning point. The surgical therapy alone or associated has a mutilating, damaging character, resulting in loss of an organ and function, most of the times with social implications, involving physical distortions with aesthetic consequences, which make the reintegration of the individual into society questionable. The problem of cervical lymph node metastases is vast and complex, reason why we approached several anatomical and physiological aspects of lymph vessels of the aero digestive organs. Among the available elements during treatment, the headquarters of the tumour, its histologic degree, and its infiltrative nature, each of them significantly influences the possibility of developing metastases.

Investigation on the upper Paleozoic Strata in Tang-e-Zakeen, and introducing Zakeen formation, Kuh-e Faraghan Zagros Basin, South Iran

International Nuclear Information System (INIS)

Ghavidel-Syooki, M.

1998-01-01

A thick clastic sequence is well-developed in Tang-e-Zakeen, Kuh-e-Faraghan, being situated approximately 80 Km north of Bandar Abbas. The sequence is 340 m. thick and mainly consists of sandstone, siltstone, shale and subordinate dolomitic beds. So far, this clastic sequence has been called Faraghan Formation. This rock unit lacks marine fauna and based on stratigraphic position, it was assigned to the Early Permian (Szabo and Kheradpir, 1978). Since then, a detailed palynological study has been carried out on the Faraghan Formation by the author. These studies resulted identification of numerous palynomorph taxa, including miospore and acritarch species. The known palynomorph taxa indicated that, a major part of Faraghan Formation belongs to the Devonian Period, while the rest is Early Permian. As a result, the National Iranian Stratigraphic Committee decided and agreed upon to divide the Faraghan Formation into two rock units, namely, the Zakeen Formation, embracing the Devonian strata, and Faraghan Formation for the Early Permian sequence in the Zagros Basin respectively. The Zakeen Formation derives from the Zakeen Village which is located in the southern flank of Kuh-e-Faraghan, about 80 km north of Bandar Abbas. The type section of Zakeen Formation attains a thickness of 285m. in Tang-e-Zakeen, Kuh-e-Faraghan, approximately 23 Km from the Zakeen village. It disconformably rests on the Sarchahan Formation, while it too, disconformably overlain by the Faraghan Formation. A total of 100 samples from the Zakeen Formation were selected and treated in the palynological laboratory of the Exploration Division of National Iranian Oil Company. 63 palynomorph taxa were encountered from the Zakeen Formation. The known species were arranged in five local stratigraphic assemblage zones. Zones I and II occur in a thickness of 96 m. of the Zakeen Formation, in ascending order, suggesting the Early Devonian whereas Zones III and IV occur Within 156 m. interval of the Zakeen

Devonian to Early Carboniferous magmatic alkaline activity in the Tafilalt Province, Eastearn Morocco: An Eovariscan episode in the Gondwana margin, north of the West African Craton

Science.gov (United States)

Pouclet, André; El Hadi, Hassan; Bardintzeff, Jacques-Marie; Benharref, Mohammed; Fekkak, Abdelilah

2017-05-01

To the eastern edge of the Moroccan Anti-Atlas, the Tafilalt Province is the repository of a Lower Palaeozoic platform and basin sedimentation constrained by a W-E and NW-SE fault network. During the mid-late Devonian, an extensional tectonic activity, demonstrated by sharp changes in sediment thickness and development of syn-sedimentary faults, was contemporaneous with a significant magmatic activity. A great number of doleritic dykes, sills, and laccoliths intruded sedimentary Silurian to Lower Visean strata. The intrusions were linked to sub-water volcanic activities with spilitic lava flows and pyroclastites during two main pulses in the Famennian-Tournaisian and in the Early Visean. The rocks consist of basaltic dolerites, lamprophyric dolerites and analcite-bearing camptonites, sharing a sodic alkaline magma composition. The magma derived from low partial melting degree of the metasome layer of the lithospheric subcontinental mantle, below the spinel-garnet transition zone. This Tafilalt tectono-magmatic activity was coeval with the Eovariscan phase in the Moroccan Meseta, which was responsible for the opening of Western Meseta basins and their transitional to alkaline volcanic activities in the Late Devonian to Early Carboniferous time.

Mercury and Dissolved Organic Matter Dynamics During Snowmelt in the Upper Provo River, Utah, USA

Science.gov (United States)

Packer, B. N.; Carling, G. T.; Nelson, S.; Aanderud, Z.; Shepherd Barkdull, N.; Gabor, R. S.

2017-12-01

Mercury (Hg) is deposited to mountains by atmospheric deposition and mobilized during snowmelt runoff, leading to Hg contamination in otherwise pristine watersheds. Mercury is typically transported with dissolved organic matter (DOM) from soils to streams and lakes. This study focused on Hg and DOM dynamics in the snowmelt-dominated upper Provo River watershed, northern Utah, USA. We sampled Hg, dissolved organic carbon (DOC) concentrations, and DOM fluorescence in river water, snowpack, and ephemeral streams over four years from 2014-2017 to investigate Hg transport mechanisms. During the snowmelt season (April through June), Hg concentrations typically increased from 1 to 8 ng/L showing a strong positive correlation with DOC. The dissolved Hg fraction was dominant in the river, averaging 75% of total Hg concentrations, suggesting that DOC is more important for transport than suspended particulate matter. Ephemeral channels, which represent shallow flow paths with strong interactions with soils, had the highest Hg (>10 ng/L) and DOC (>10 mg/L) concentrations, suggesting a soil water source of Hg and organic matter. Fluorescence spectroscopy results showed important changes in DOM type and quality during the snowmelt season and the soil water flow paths are activated. Changes in DOM characteristics during snowmelt improve the understanding of Hg dynamics with organic matter and elucidate transport pathways from the soil surface, ephemeral channels and groundwater to the Provo River. This study has implications for understanding Hg sources and transport mechanisms in mountain watersheds.

Stratigraphic significance and resolution of spectral reflectance logs in Lower Devonian carbonates of the Barrandian area, Czech Republic; a correlation with magnetic susceptibility and gamma-ray logs

Czech Academy of Sciences Publication Activity Database

Koptíková, Leona; Bábek, O.; Hladil, Jindřich; Kalvoda, J.; Slavík, Ladislav

2010-01-01

Roč. 225, 3/4 (2010), s. 83-98 ISSN 0037-0738 R&D Projects: GA AV ČR IAAX00130702; GA ČR GA205/08/0767 Institutional research plan: CEZ:AV0Z30130516 Keywords : VIS spectral reflectance * cyclostratigraphy * sea -level changes * Lower Devonian * red pelagic carbonates * diagenesis Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.685, year: 2010

Geochemical Aspects of Formation of Large Oil Deposits in the Volga-Ural Sedimentary Basin

Science.gov (United States)

Plotnikova, I.; Nosova, F.; Pronin, N.; Nosova, J.; Budkevich, T.

2012-04-01

The study of the rocks domanikoid type in the territory of the Ural-Volga region has an almost century-long history, beginning with the first studies of A.D. Archangelsky in the late 20's of last century. But nevertheless the question of the source of oil that formed the industrial deposits of Volga-Ural oil and gas province (OGP), where Romashkinskoye oil field occupies a special place, remains unresolved and topical. According to the sedimentary-migration theory of origin of oil and gas, it is supposed that the primary source of hydrocarbons in this area are the deposits of domanikoid type that contain a large ammount of sapropel organic matter (OM). Semiluki (domanik) horizon of srednefranski substage of the Upper Devonian is considered to be a typical domanikoid stratum. Investigation of the OM of the rocks and oils of the sedimentary cover on the basis of chromato-mass spectrometry method allows us to study the correlations between rock and oil and to assess the location (or absence) of the sources of hydrocarbons in the Paleozoic sedimentary cover. The results of geochemical study of dispersed organic matter (DOM) of rocks from Semiluksky horizon of the Upper Devonian and of the oil from Pashiysky horizon of the Middle Devonian form the basis of this paper. The objectives of this study were the following: to determine the original organic matter of the rocks, which would indicate the conditions of sedimentation of the supposed rock-oil sources; the study of chemofossils (biomarkers) in oil from Pashiyskiy horizon; and the identification of genetic association of DOM rocks from Semiluksky horizon with this oil on the basis of the oil-DOM correlation. The study of biomarkers was carried out with the help of chromato-mass spectrometry in the Laboratory of Geochemistry of Fossil Fuels (Kazan Federal University). In this study we used several informative parameters characterizing the depositional environment, the type of source OM and its maturity: STER / PENT, h

FRASNIAN AND VISEAN-NAMURIAN CONODONT FAUNAS AT PRAPROTNO, SLOVENIA

OpenAIRE

KOLAR-JURKOVSEK, TEA; JURKOVSEK, BOGDAN

2017-01-01

Conodont faunas from the limestone pebbles of the Upper Paleozoic Conglomerate at Praprotno, Slovenia demonstrate the presence of two faunas. The older fauna, marked by Palmatolepis surecta and Polygnathus decorosus is indicative of the Frasnian stage (Upper Devonian). The younger fauna is dominated by Gnathodus bilineatus and contains Lochriea commutata and L. nodosa. This fauna is characteristic of the Late Visean-Namurian (Lower Carboniferous).

Petrogenesis and tectonic implications of Late Devonian arc volcanic rocks in southern Beishan orogen, NW China: Geochemical and Nd-Sr-Hf isotopic constraints

Science.gov (United States)

Guo, Qian-Qian; Chung, Sun-Lin; Xiao, Wen-Jiao; Hou, Quan-Lin; Li, Shan

2017-05-01

Late Devonian (ca. 370 Ma) volcanic rocks provide important information about the nature of magmatism during the tectonic transition between the Early and Late Paleozoic in the Beishan orogen, southern Central Asian Orogenic Belt. They are predominantly an andesitic-dacitic-rhyolitic assemblage, characterized by alkali contents ranging from slightly calcic to slightly alkaline. The rhyolitic rocks are generally ferroan, whereas the andesitic rocks are magnesian. These volcanic rocks exhibit similar trace element characteristics to those of continental arcs. Strongly negative εNd(t) values (- 2.8 to - 3.6) and high Sr isotopic compositions (initial 87Sr/86Sr = 0.7036-0.7108) suggest that they are mainly derived from an ancient crust. However, the positive zircon εHf(t) values (+ 1.4 to + 16.4) support the role of juvenile components in their genesis, indicating the significant input of new mantle-derived magmas. These characteristics imply a hybrid derivation, from an ancient crustal source with the addition of juvenile materials during magma genesis, or perhaps heterogeneous contamination or hybridization during magma emplacement. Combined with the regional geology, our results indicate that the Late Devonian magmatism resulted from a southward retreat of the subduction zone, which records significant continental crustal growth in a transitional arc or an accretionary arc setting. The distinct geochemical compositions, especially the Nd-Hf isotope decoupling of the Dundunshan volcanic rocks, imply a significant change in the geodynamic setting in the Late Paleozoic.

Thermal alterations of organic matter in coal wastes from Upper Silesia, Poland

Science.gov (United States)

Misz-Kennan, Magdalena

2010-01-01

Self-heating and self-combustion are currently taking place in some coal waste dumps in the Upper Silesian Coal Basin, Poland, e.g. the dumps at Rymer Cones, Starzykowiec, and the Marcel Coal Mine, all in the Rybnik area. These dumps are of similar age and self-heating and combustion have been occurring in all three for many years. The tools of organic petrography (maceral composition, rank, etc.), gas chromatography-mass spectrometry, and proximate and ultimate analysis are used to investigate the wastes. Organic matter occurs in quantities up to 85 vol.%, typically a few to several vol.%, in the wastes. All three maceral groups (vitrinite, liptinite, and inertinite) are present as unaltered and variously-altered constituents associated with newly-formed petrographic components (bitumen expulsions, pyrolytic carbon). The predominant maceral group is vitrinite with alterations reflected in the presence of irregular cracks, oxidation rims and, rarely, devolatilisation pores. In altered wastes, paler grey-vitrinite and/or coke dominates. The lack of plasticity, the presence of paler-coloured particles, isotropic massive coke, dispersed coked organic matter, and expulsions of bitumens all indicate that heating was slow and extended over a long time. Macerals belonging to other groups are present in unaltered form or with colours paler than the colours of the parent macerals. Based on the relative contents of organic compounds, the most important groups of these identified in the wastes are n-alkanes, acyclic isoprenoids, hopanes, polycyclic aromatic hydrocarbons (PAHs) and their derivatives, phenol and its derivatives. These compounds occur in all wastes except those most highly altered where they were probably destroyed by high temperatures. These compounds were generated mainly from liptinite-group macerals. Driven by evaporation and leaching, they migrated within and out of the dump. Their presence in some wastes in which microscopically visible organic matter is

Organic chemistry in Titan's upper atmosphere and its astrobiological consequences: I. Views towards Cassini plasma spectrometer (CAPS) and ion neutral mass spectrometer (INMS) experiments in space

Science.gov (United States)

Ali, A.; Sittler, E. C.; Chornay, D.; Rowe, B. R.; Puzzarini, C.

2015-05-01

The discovery of carbocations and carbanions by Ion Neutral Mass Spectrometer (INMS) and the Cassini Plasma Spectrometer (CAPS) instruments onboard the Cassini spacecraft in Titan's upper atmosphere is truly amazing for astrochemists and astrobiologists. In this paper we identify the reaction mechanisms for the growth of the complex macromolecules observed by the CAPS Ion Beam Spectrometer (IBS) and Electron Spectrometer (ELS). This identification is based on a recently published paper (Ali et al., 2013. Planet. Space Sci. 87, 96) which emphasizes the role of Olah's nonclassical carbonium ion chemistry in the synthesis of the organic molecules observed in Titan's thermosphere and ionosphere by INMS. The main conclusion of that work was the demonstration of the presence of the cyclopropenyl cation - the simplest Huckel's aromatic molecule - and its cyclic methyl derivatives in Titan's atmosphere at high altitudes. In this study, we present the transition from simple aromatic molecules to the complex ortho-bridged bi- and tri-cyclic hydrocarbons, e.g., CH2+ mono-substituted naphthalene and phenanthrene, as well as the ortho- and peri-bridged tri-cyclic aromatic ring, e.g., perinaphthenyl cation. These rings could further grow into tetra-cyclic and the higher order ring polymers in Titan's upper atmosphere. Contrary to the pre-Cassini observations, the nitrogen chemistry of Titan's upper atmosphere is found to be extremely rich. A variety of N-containing hydrocarbons including the N-heterocycles where a CH group in the polycyclic rings mentioned above is replaced by an N atom, e.g., CH2+ substituted derivative of quinoline (benzopyridine), are found to be dominant in Titan's upper atmosphere. The mechanisms for the formation of complex molecular anions are discussed as well. It is proposed that many closed-shell complex carbocations after their formation first, in Titan's upper atmosphere, undergo the kinetics of electron recombination to form open-shell neutral

Comparison of fluid geochemistry and microbiology of multiple organic-rich reservoirs in the Illinois Basin, USA: Evidence for controls on methanogenesis and microbial transport

Energy Technology Data Exchange (ETDEWEB)

Schlegel, M.E.; McIntosh, J.C.; Bates, B.L.; Kirk, M.F.; Martini, A.M. [University of Arizona, Tucson, AZ (United States)

2011-04-01

The Illinois Basin, USA, is an ideal location to investigate hydrogeochemical factors controlling methanogenesis as microbial methane accumulations occur: (1) in three organic-rich reservoirs of different geologic ages and organic matter types - Upper Devonian New Albany Shale (up to 900 m depth), Pennsylvanian coals (up to 600 m depth), and Quaternary glacial sediments (shallow aquifers); (2) across steep salinity gradients; and (3) with variable concentrations of SO{sub 4}{sup 2-}. For all three organic-rich reservoirs aqueous geochemical conditions are favorable for microbial methanogenesis, with near neutral pH, SO{sub 4}{sup 2-} concentrations {gt}2 mM, and Cl{sup -} concentrations {lt}3 M. Also, carbon isotopic fractionation of CH{sub 4}, CO{sub 2}, and DIC is consistent with microbial methanogenesis, and increased carbon isotopic fractionation with average reservoir depth corresponds to a decrease of groundwater flushing rates with average depth of reservoir. Plots of stable isotopes of water and Cl{sup -} show mixing between a brine endmember and freshwater, suggesting that meteoric groundwater recharge has affected all microbial methanogenic systems. Additionally, similar methanogenic communities are present in all three reservoirs with comparable cell counts (8.69E3-2.58E6 cells/mL). TRFLP results show low numbers of archaea species with only two dominant groups of base pairs in coals, shale, and limestone aquifers. These results compare favorably with other methanogen-containing deep subsurface environments. The matching of variations between methanogenic TRFLP data and conservative tracers suggests that deep circulation of meteoric waters influenced archaeal communities in the Illinois Basin.

Three-dimensional geometry of the structural front between Berland River and Smoky River, central Alberta Foothills

Energy Technology Data Exchange (ETDEWEB)

Liu, S.; Lawton, D. C.; Spratt, D. A. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

1996-06-01

Geometry of the triangle zone and its variations in the region lying between the Berland River and the Smoky River in the central Alberta Foothills was described by drawing closely spaced balanced structural cross-sections, constrained by seismic data interpretation and well-log analysis. The stratigraphic sequence (Devonian to Tertiary in the northwest, or Mississipian to Tertiary in the southeast) was found to have been divided into three structural packages by three detachments. In the northwest, the lower detachment lies in the Lower Devonian Woodbend Group, the middle detachment in the Shaftesbury Formation, and the upper detachment in the upper Kaskapau Formation. Each of these detachment combined with the foreland-verging thrust sheet beneath them to form the triangle zone structure. Based on the peculiarities of the geology, it is suspected that the higher triangle zone was formed before the lower triangle zone. 31 refs., 10 figs.

Evaluation of diffuse diseases of the upper abdominal organs by MRI. Determination of a normal range in signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images and evaluation of diffuse diseases of an organ by using it

International Nuclear Information System (INIS)

Mitsuhashi, Hiroshi

1995-01-01

Diffuse diseases of the upper abdominal organs, including the liver, spleen, pancreas, and vertebral marrow, were evaluated by using signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images. Conventional T1- and T2-weighted images were obtained in 1.5 T MR system in 203 persons, including 122 controls and 81 patients with a diffuse disease in the upper abdominal organ. In controls, though there was neither sexual nor age difference in signal intensity ratios of the liver and pancreas, those of the spleen and vertebral marrow showed sexual and age difference, respectively. A normal range of signal intensity ratio of each organ in each image was determined in each decade of each sex by using controls. The signal intensity ratio of the liver was significantly low in T1- and T2-weighted images in patients with abundant iron deposit and within normal limits in patients with liver cirrhosis or scant iron deposit. The signal intensity ratio of the liver was significantly high only in a T2-weighted image in patients with fatty deposit in the liver, which was suspected to be due to inflammatory change in the liver with fatty deposit. The signal intensity ratios of the spleen, pancreas, and vertebral marrow were significantly low only in a T2-weighted image in patients with iron metabolic disturbance. The signal intensity ratio of the pancreas was significantly high in 40% of patients with acute and/or chronic pancreatitis, which was more sensitive in detection of pancreatitis than data in other studies. it can be concluded that the signal intensity ratio of each organ to the renal medulla in T1- and T2-weighted images is useful for detection of diffuse diseases of the upper abdominal organs by using the normal range in each decade of each sex. (S.Y.)

Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin

Science.gov (United States)

Phan, Thai T.; Capo, Rosemary C; Stewart, Brian W.; Macpherson, Gwen; Rowan, Elisabeth L.; Hammack, Richard W.

2015-01-01

In this study, water and whole rock samples from hydraulically fractured wells in the Marcellus Shale (Middle Devonian), and water from conventional wells producing from Upper Devonian sandstones were analyzed for lithium concentrations and isotope ratios (δ7Li). The distribution of lithium concentrations in different mineral groups was determined using sequential extraction. Structurally bound Li, predominantly in clays, accounted for 75-91 wt. % of total Li, whereas exchangeable sites and carbonate cement contain negligible Li (< 3%). Up to 20% of the Li is present in the oxidizable fraction (organic matter and sulfides). The δ7Li values for whole rock shale in Greene Co., Pennsylvania, and Tioga Co., New York, ranged from -2.3 to + 4.3‰, similar to values reported for other shales in the literature. The δ7Li values in shale rocks with stratigraphic depth record progressive weathering of the source region; the most weathered and clay-rich strata with isotopically light Li are found closest to the top of the stratigraphic section. Diagenetic illite-smectite transition could also have partially affected the bulk Li content and isotope ratios of the Marcellus Shale.

Lower Paleozoic deep-water facies of the Medfra area, central Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1997

Science.gov (United States)

Dumoulin, Julie A.; Bradley, Dwight C.; Harris, Anita G.; Repetski, John E.

1999-01-01

Deep-water facies, chiefly hemipelagic deposits and turbidites, of Cambrian through Devonian age are widely exposed in the Medfra and Mt. McKinley quadrangles. These strata include the upper part of the Telsitna Formation (Middle-Upper Ordovician) and the Paradise Fork Formation (Lower Silurian-Lower Devonian) in the Nixon Fork terrane, the East Fork Hills Formation (Upper Cambrian-Lower Devonian) in the East Fork subterrane of the Minchumina terrane, and the chert and argillite unit (Ordovician) and the argillite and quartzite unit (Silurian- Devonian? and possibly older) in the Telida subterrane of the Minchumina terrane.In the western part of the study area (Medfra quadrangle), both hemipelagic deposits and turbidites are largely calcareous and were derived from the Nixon Fork carbonate platform. East- ern exposures (Mt. McKinley quadrangle; eastern part of the Telida subterrane) contain much less carbonate; hemipelagic strata are mostly chert, and turbidites contain abundant rounded quartz and lesser plagioclase and potassium feldspar. Deep-water facies in the Medfra quadrangle correlate well with rocks of the Dillinger terrane exposed to the south (McGrath quadrangle), but coeval strata in the Mt. McKinley quadrangle are compositionally similar to rocks to the northeast (Livengood quadrangle). Petrographic data thus suggest that the Telida subterranes presently defined is an artificial construct made up of two distinct sequences of disparate provenance.Restoration of 90 and 150 km of dextral strike-slip on the Iditarod and Farewell faults, respectively, aligns the deep-water strata of the Minchumina and Dillinger terranes in a position east of the Nixon Fork carbonate platform. This restoration supports the interpretation that lower Paleozoic rocks in the Nixon Fork and Dillinger terranes, and in the western part of the Minchumina terrane (East Fork subterrane and western part of the Telida subterrane), formed along a single continental margin. Rocks in the

Continental crust melting induced by subduction initiation of the South Tianshan Ocean: Insight from the Latest Devonian granitic magmatism in the southern Yili Block, NW China

Science.gov (United States)

Bao, Zihe; Cai, Keda; Sun, Min; Xiao, Wenjiao; Wan, Bo; Wang, Yannan; Wang, Xiangsong; Xia, Xiaoping

2018-03-01

The Tianshan belt of the southwestern Central Asian Orogenic Belt was generated by Paleozoic multi-stage subduction and final closure of several extinct oceans, including the South Tianshan Ocean between the Kazakhstan-Yili and Tarim blocks. However, the subduction initiation and polarity of the South Tianshan Ocean remain issues of highly debated. This study presents new zircon U-Pb ages, geochemical compositions and Sr-Nd isotopes, as well as zircon Hf isotopic data of the Latest Devonian to Early Carboniferous granitic rocks in the Wusun Mountain of the Yili Paleozoic convergent margin, which, together with the spatial-temporal distributions of regional magmatic rocks, are applied to elucidate their petrogenesis and tectonic linkage to the northward subduction initiation of the South Tianshan Ocean. Our zircon U-Pb dating results reveal that these granites were emplaced at the time interval of 362.0 ± 1.2-360.3 ± 1.9 Ma, suggesting a marked partial melting event of the continental crust in the Latest Devonian to Early Carboniferous. These granites, based on their mineral compositions and textures, can be categorized as monzogranites and K-feldspar granites. Geochemically, both monzogranites and K-feldspar granites have characters of I-type granites with high K2O contents (4.64-4.83 wt.%), and the K-feldspar granites are highly fractionated I-type granites, while the monzogranites have features of unfractionated I-type granites. Whole-rock Sr-Nd isotopic modeling results suggest that ca. 20-40% mantle-derived magmas may be involved in magma mixing with continental crust partial melts to generate the parental magmas of the granites. The mantle-derived basaltic magmas was inferred not only to be a major component of magma mixture but also as an important heat source to fuse the continental crust in an extensional setting, which is evidenced by the high zircon saturation temperatures (713-727 °C and 760-782 °C) of the studied granites. The Latest Devonian to

Studies on improvement of diagnostic ability of computed tomography (CT) in the parenchymatous organs in the upper abdomen, 1

International Nuclear Information System (INIS)

Kawata, Ryo

1982-01-01

1) The upper abdominal compression method was easily applicable for CT examination in practically all the patients. It gave no harm and considerably improved CT diagnosis. 2) The materials used for compression were foamed polystyrene, the Mix-Dp and a water bag. When CT examination was performed to diagnose such lesions as a circumscribed tumor, compression with the Mix-Dp was most useful, and when it was performed for screening examination of upper abdominal diseases, compression with a water bag was most effective. 3) Improvement in contour-depicting ability of CT by the compression method was most marked at the body of the pancreas, followed by the head of the pancreas and the posterior surface of the left lobe of the liver. Slight improvement was seen also at the tail of the pancreas and the left adrenal gland. 4) Improvement in organ-depicting ability of CT by the compression method was estimated by a 4-category classification method. It was found that the improvement was most marked at the body and the head of the pancreas. Considerable improvement was observed also at the left lobe of the liver and the both adrenal glands. Little improvement was obtained at the spleen. When contrast enhancement was combined with the compression method, improvement at such organs which were liable to be enhanced, as the liver and the adrenal glands, was promoted, while the organ-depicting ability was decreased at the pancreas. 5) By comparing the CT image under compression with that without compression, continuous infiltrations of gastric cancer into the body and the tail of the pancreas in 2 cases and a retroperitoneal infiltration of pancreatic tumor in 1 case were diagnosed preoperatively. (J.P.N.)

Characterization and analysis of Devonian shales as related to release of gaseous hydrocarbons. Well V-7 Wetzel County, West Virginia

Energy Technology Data Exchange (ETDEWEB)

Kalyoncu, R.S.; Boyer, J.P.; Snyder, M.J.

1979-08-15

This program was initiated in September 1976, with the objective and scope of determining the relationships between the shale characteristics, hydrocarbon gas contents, and well location, and thereby provide a sound basis for (1) assessing the productive capacity of the Eastern Devonian Gas Shale deposits, and (2) guiding research, development and demonstration projects to enhance the recovery of natural gas from the shale deposits. Included in the scope of the program are a number of elemental tasks as a part of the Resource Inventory and Shale Characterization subprojects of DOE's Eastern Gas Shales Project designed to provide large quantities of support data for current and possibly future needs of the Project.

Geochemical constraints on the origin and volume of gas in the New Albany Shale (Devonian-Mississippian), eastern Illinois Basin

Science.gov (United States)

Strapoc, D.; Mastalerz, Maria; Schimmelmann, A.; Drobniak, A.; Hasenmueller, N.R.

2010-01-01

This study involved analyses of kerogen petrography, gas desorption, geochemistry, microporosity, and mesoporosity of the New Albany Shale (Devonian-Mississippian) in the eastern part of the Illinois Basin. Specifically, detailed core analysis from two locations, one in Owen County, Indiana, and one in Pike County, Indiana, has been conducted. The gas content in the locations studied was primarily dependent on total organic carbon content and the micropore volume of the shales. Gas origin was assessed using stable isotope geochemistry. Measured and modeled vitrinite reflectance values were compared. Depth of burial and formation water salinity dictated different dominant origins of the gas in place in the two locations studied in detail. The shallower Owen County location (415-433 m [1362-1421 ft] deep) contained significant additions of microbial methane, whereas the Pike County location (832-860 m [2730-2822 ft] deep) was characterized exclusively by thermogenic gas. Despite differences in the gas origin, the total gas in both locations was similar, reaching up to 2.1 cm3/g (66 scf/ton). Lower thermogenic gas content in the shallower location (lower maturity and higher loss of gas related to uplift and leakage via relaxed fractures) was compensated for by the additional generation of microbial methane, which was stimulated by an influx of glacial melt water, inducing brine dilution and microbial inoculation. The characteristics of the shale of the Maquoketa Group (Ordovician) in the Pike County location are briefly discussed to provide a comparison to the New Albany Shale. Copyright ??2010. The American Association of Petroleum Geologists. All rights reserved.

Respiration-induced movement of the upper abdominal organs: a pitfall for the three-dimensional conformal radiation treatment of pancreatic cancer

International Nuclear Information System (INIS)

Bussels, Barbara; Goethals, Laurence; Feron, Michel; Bielen, Didier; Dymarkowski, Steven; Suetens, Paul; Haustermans, Karin

2003-01-01

Respiration-induced movement of the upper abdominal organs (pancreas, liver and kidneys) was assessed in 12 subjects using dynamic magnetic resonance imaging. The movement of each organ in the cranio-caudal, the lateral and the anterior-posterior direction was deduced from the movement of the center of gravity on two-dimensional images. This center of gravity was computed from the volume delineated on sequential 8-mm slices of both sagittal and coronal dynamic series. The largest movements were noticed in the cranio-caudal direction for pancreas and liver (23.7±15.9 mm and 24.4±16.4 mm). The kidneys showed smaller movements in the cranio-caudal direction (left kidney 16.9±6.7 mm and right kidney 16.1±7.9 mm). The movements of the different organs in the anterior-posterior and lateral directions were less pronounced. It is of the greatest importance to be aware of these movements in the planning of a conformal radiation treatment for pancreatic cancer

Upper temperature limits of tropical marine ectotherms: global warming implications.

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Khanh Dung T Nguyen

Full Text Available Animal physiology, ecology and evolution are affected by temperature and it is expected that community structure will be strongly influenced by global warming. This is particularly relevant in the tropics, where organisms are already living close to their upper temperature limits and hence are highly vulnerable to rising temperature. Here we present data on upper temperature limits of 34 tropical marine ectotherm species from seven phyla living in intertidal and subtidal habitats. Short term thermal tolerances and vertical distributions were correlated, i.e., upper shore animals have higher thermal tolerance than lower shore and subtidal animals; however, animals, despite their respective tidal height, were susceptible to the same temperature in the long term. When temperatures were raised by 1°C hour(-1, the upper lethal temperature range of intertidal ectotherms was 41-52°C, but this range was narrower and reduced to 37-41°C in subtidal animals. The rate of temperature change, however, affected intertidal and subtidal animals differently. In chronic heating experiments when temperature was raised weekly or monthly instead of every hour, upper temperature limits of subtidal species decreased from 40°C to 35.4°C, while the decrease was more than 10°C in high shore organisms. Hence in the long term, activity and survival of tropical marine organisms could be compromised just 2-3°C above present seawater temperatures. Differences between animals from environments that experience different levels of temperature variability suggest that the physiological mechanisms underlying thermal sensitivity may vary at different rates of warming.

Earth’s oldest ‘Bobbit worm’ – gigantism in a Devonian eunicidan polychaete

Science.gov (United States)

Eriksson, Mats E.; Parry, Luke A.; Rudkin, David M.

2017-01-01

Whilst the fossil record of polychaete worms extends to the early Cambrian, much data on this group derive from microfossils known as scolecodonts. These are sclerotized jaw elements, which generally range from 0.1–2 mm in size, and which, in contrast to the soft-body anatomy, have good preservation potential and a continuous fossil record. Here we describe a new eunicidan polychaete, Websteroprion armstrongi gen. et sp. nov., based primarily on monospecific bedding plane assemblages from the Lower-Middle Devonian Kwataboahegan Formation of Ontario, Canada. The specimens are preserved mainly as three-dimensional moulds in the calcareous host rock, with only parts of the original sclerotized jaw walls occasionally present. This new taxon has a unique morphology and is characterized by an unexpected combination of features seen in several different Palaeozoic polychaete families. Websteroprion armstrongi was a raptorial feeder and possessed the largest jaws recorded in polychaetes from the fossil record, with maxillae reaching over one centimetre in length. Total body length of the species is estimated to have reached over one metre, which is comparable to that of extant ‘giant eunicid’ species colloquially referred to as ‘Bobbit worms’. This demonstrates that polychaete gigantism was already a phenomenon in the Palaeozoic, some 400 million years ago. PMID:28220886

The influence of hurricanes upon the quiet depositional conditions in the Lower Emsian La Vid shales of Colle (NW Spain)

NARCIS (Netherlands)

Stel, Jan H.

1976-01-01

The author supposes that the fossil content of thin carbonate units in the Upper La Vid shales (Lower Devonian) of Colle was influenced by heavy storms like hurricanes. Apart from microplankton (Cramer, 1964) no fossils are found in the shales. Together with the very well developed fissility of the

Regional geological assessment of the Devonian-Mississippian shale sequence of the Appalachian, Illinois, and Michigan basins relative to potential storage/disposal of radioactive wastes

Energy Technology Data Exchange (ETDEWEB)

Lomenick, T.F.; Gonzales, S.; Johnson, K.S.; Byerly, D.

1983-01-01

The thick and regionally extensive sequence of shales and associated clastic sedimentary rocks of Late Devonian and Early Mississippian age has been considered among the nonsalt geologies for deep subsurface containment of high-level radioactive wastes. This report examines some of the regional and basin-specific characteristics of the black and associated nonblack shales of this sequence within the Appalachian, Illinois, and Michigan basins of the north-central and eastern United States. Principal areas where the thickness and depth of this shale sequence are sufficient to warrant further evaluation are identified, but no attempt is made to identify specific storage/disposal sites. Also identified are other areas with less promise for further study because of known potential conflicts such as geologic-hydrologic factors, competing subsurface priorities involving mineral resources and groundwater, or other parameters. Data have been compiled for each basin in an effort to indicate thickness, distribution, and depth relationships for the entire shale sequence as well as individual shale units in the sequence. Included as parts of this geologic assessment are isopach, depth information, structure contour, tectonic elements, and energy-resource maps covering the three basins. Summary evaluations are given for each basin as well as an overall general evaluation of the waste storage/disposal potential of the Devonian-Mississippian shale sequence,including recommendations for future studies to more fully characterize the shale sequence for that purpose. Based on data compiled in this cursory investigation, certain rock units have reasonable promise for radioactive waste storage/disposal and do warrant additional study.

Regional geological assessment of the Devonian-Mississippian shale sequence of the Appalachian, Illinois, and Michigan basins relative to potential storage/disposal of radioactive wastes

International Nuclear Information System (INIS)

Lomenick, T.F.; Gonzales, S.; Johnson, K.S.; Byerly, D.

1983-01-01

The thick and regionally extensive sequence of shales and associated clastic sedimentary rocks of Late Devonian and Early Mississippian age has been considered among the nonsalt geologies for deep subsurface containment of high-level radioactive wastes. This report examines some of the regional and basin-specific characteristics of the black and associated nonblack shales of this sequence within the Appalachian, Illinois, and Michigan basins of the north-central and eastern United States. Principal areas where the thickness and depth of this shale sequence are sufficient to warrant further evaluation are identified, but no attempt is made to identify specific storage/disposal sites. Also identified are other areas with less promise for further study because of known potential conflicts such as geologic-hydrologic factors, competing subsurface priorities involving mineral resources and groundwater, or other parameters. Data have been compiled for each basin in an effort to indicate thickness, distribution, and depth relationships for the entire shale sequence as well as individual shale units in the sequence. Included as parts of this geologic assessment are isopach, depth information, structure contour, tectonic elements, and energy-resource maps covering the three basins. Summary evaluations are given for each basin as well as an overall general evaluation of the waste storage/disposal potential of the Devonian-Mississippian shale sequence,including recommendations for future studies to more fully characterize the shale sequence for that purpose. Based on data compiled in this cursory investigation, certain rock units have reasonable promise for radioactive waste storage/disposal and do warrant additional study

Hypnosis and upper digestive function and disease

Science.gov (United States)

Chiarioni, Giuseppe; Palsson, Olafur S; Whitehead, William E

2008-01-01

Hypnosis is a therapeutic technique that primarily involves attentive receptive concentration. Even though a small number of health professionals are trained in hypnosis and lingering myths and misconceptions associated with this method have hampered its widespread use to treat medical conditions, hypnotherapy has gained relevance as an effective treatment for irritable bowel syndrome not responsive to standard care. More recently, a few studies have addressed the potential influence of hypnosis on upper digestive function and disease. This paper reviews the efficacy of hypnosis in the modulation of upper digestive motor and secretory function. The present evidence of the effectiveness of hypnotherapy as a treatment for functional and organic diseases of the upper bowel is also summarized, coupled with a discussion of potential mechanisms of its therapeutic action. PMID:19009639

Analysis of the structural parameters that influence gas production from the Devonian shale. Annual progress report, 1979-1980. Volume II. Data repository and reports published during fiscal year 1979-1980: regional structure, surface structure, surface fractures, hydrology

Energy Technology Data Exchange (ETDEWEB)

Negus-De Wys, J.; Dixon, J. M.; Evans, M. A.; Lee, K. D.; Ruotsala, J. E.; Wilson, T. H.; Williams, R. T.

1980-10-01

This volume comprises appendices giving regional structure data, surface structure data, surface fracture data, and hydrology data. The fracture data covers oriented Devonian shale cores from West Virginia, Ohio, Virginia, Pennsylvania, and Kentucky. The subsurface structure of the Eastern Kentucky gas field is also covered. (DLC)

Effects of ancient porosity and permeability on formation of sedimentary dolomites: Devonian Jefferson Formation (Frasnian), south-central Montana

Energy Technology Data Exchange (ETDEWEB)

Smith, T.M.; Dorobek, S.L.

1987-08-01

Petrographic and geochemical evidence indicates that multiple dolomitization and dolomite stabilization events affected the Devonian Jefferson Formation (Frasnian) in south-central Montana. Several types of dolomite occur, defined by cathodoluminescence: nonzoned, dully luminescent subhedral-anhedral mosaics (most common), euhedral nonzoned and zoned dolomites, zoned dolomite cements, and irregularly luminescent dolomites (dully luminescent with irregularly luminescent regions). The irregularly luminescent fabrics probably represent partial replacement of early dolomite phases with later dolomite phases. Nonzoned, Ca-enriched, euhedral dolomites occur in calcite-cemented, coarse-grained limestone layers. These permeable layers probably were conduits for early meteoric waters, that occluded porosity in the limestones and prevented later dolomite stabilization. Irregularly luminescent dolomites are interpreted as intermediate fabrics in the dolomite stabilization process. Later calcite cements which occlude intercrystalline porosity prevented further dolomite replacement. Total recrystallization of remaining dolomites and formation of final dully luminescent mosaics occurred prior to brecciation and stylolitization.

GIVETIAN–FRASNIAN BOUNDARY CONODONTS FROM KERMAN PROVINCE, CENTRAL IRAN

Directory of Open Access Journals (Sweden)

HOSSEIN GHOLAMALIAN

2013-07-01

Full Text Available The Middle - Late Devonian boundary is investigated based on twenty-two conodont species and subspecies from three sections in the north and west of Kerman, southeastern central Iran. Upper Givetian - lower Frasnian carbonates of the basal part of the Bahram Formation transgressively overlie the sandstone beds of the top of (? Early - Middle Devonian Padeha Formation. These massive skeletal limestones encompass the G-F boundary. The base of Frasnian is identified by the appearance of early forms of Ancyrodella rotundiloba . It helps to compare our biozones to those of global stratotype in southern France. A new species, Polygnathus hojedki n. sp. is described here. New range is suggested for P. praepolitus .

Characteristics of dissolved organic matter in the Upper Klamath River, Lost River, and Klamath Straits Drain, Oregon and California

Science.gov (United States)

Goldman, Jami H.; Sullivan, Annett B.

2017-12-11

Concentrations of particulate organic carbon (POC) and dissolved organic carbon (DOC), which together comprise total organic carbon, were measured in this reconnaissance study at sampling sites in the Upper Klamath River, Lost River, and Klamath Straits Drain in 2013–16. Optical absorbance and fluorescence properties of dissolved organic matter (DOM), which contains DOC, also were analyzed. Parallel factor analysis was used to decompose the optical fluorescence data into five key components for all samples. Principal component analysis (PCA) was used to investigate differences in DOM source and processing among sites.At all sites in this study, average DOC concentrations were higher than average POC concentrations. The highest DOC concentrations were at sites in the Klamath Straits Drain and at Pump Plant D. Evaluation of optical properties indicated that Klamath Straits Drain DOM had a refractory, terrestrial source, likely extracted from the interaction of this water with wetland peats and irrigated soils. Pump Plant D DOM exhibited more labile characteristics, which could, for instance, indicate contributions from algal or microbial exudates. The samples from Klamath River also had more microbial or algal derived material, as indicated by PCA analysis of the optical properties. Most sites, except Pump Plant D, showed a linear relation between fluorescent dissolved organic matter (fDOM) and DOC concentration, indicating these measurements are highly correlated (R2=0.84), and thus a continuous fDOM probe could be used to estimate DOC loads from these sites.

Precise position of the Basal Choteč event and evolution of sedimentary environments near the Lower–Middle Devonian boundary: The magnetic susceptibility, gamma-ray spectrometric, lithological, and geochemical record of the Prague Synform (Czech Republic)

Czech Academy of Sciences Publication Activity Database

Koptíková, Leona

2011-01-01

Roč. 304, 1/2 (2011), s. 96-112 ISSN 0031-0182 R&D Projects: GA AV ČR KJB307020602; GA AV ČR IAAX00130702 Institutional research plan: CEZ:AV0Z30130516 Keywords : magnetic susceptibility * Gamma-ray spectrometry * Prague Synform * Lower–Middle Devonian Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.392, year: 2011

Review of Topical Treatment of Upper Tract Urothelial Carcinoma

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Kenneth G. Nepple

2009-01-01

Full Text Available A select group of patients with upper tract urothelial carcinoma may be appropriate candidates for minimally invasive management. Organ-preserving endoscopic procedures may be appropriate for patients with an inability to tolerate major surgery, solitary kidney, bilateral disease, poor renal function, small tumor burden, low-grade disease, or carcinoma in situ. We review the published literature on the use of topical treatment for upper tract urothelial carcinoma and provide our approach to treatment in the office setting.

A review of the petroleum geochemistry of the Precaspian Basin

Energy Technology Data Exchange (ETDEWEB)

Pairazian, V.V. [All-Russian Geological Oil Research and Prospecting Inst. (VNIGNI), Moscow (Russian Federation); ENI-AGIP, San Donato Milanese (Italy)

1999-11-01

On the territory of the former Soviet Union more than 30- oil and gas-bearing basins have been defined. Among them the Precaspian basin is one of the most prolific in terms of oil and gas exploration and production. The basin is situated in the southeastern part of the East European Platform and covers an areas of about 500 000 km{sup 2}. There are a number of source rocks of different ages, among which the principal ones are Lower Permian, Middle Carboniferous and Middle Devonian marine shales and carbonates. The post-salt Mesozoic sources are of less significance. Geological and geochemical data interpretation allows the main oil/gas accumulation zones and new exploration prospects to be defined. Two main petroleum systems are recognised in the Palaeozoic sequence of the basin, containing 90% of the recoverable hydrocarbon resources: Lower Permian-Middle Carboniferous and Lower Carboniferous-Upper Devonian. The new exploration targets are deep Middle Devonian clastic reservoirs on the passive continental margins and Middle Carboniferous (Bashkirian) carbonates in the Caspian offshore part of the basin. (Author)

A Case Report on Upper Extremity Pain of Cardiac Origin

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Turgay Altınbilek

2016-08-01

Full Text Available Upper extremity pain can originate from the musculoskeletal system, or be a reflection of problems originating from various organs. Therefore, it is highly important to perform a detailed clinical evaluation on patients during differential diagnosis. In this case report, we present a 61 year-old male patient who was admitted with pain in both upper extremities and the upper back that presumed to be of cardiac origin following our clinical evaluations. The patient was referred to the cardiology department, where he was diagnosed with coronary heart disease. The patient’s complaints of pain were fully resolved through the application of an intracoronary stent.

ORIGINAL ARTICLE ORIG ORIG CT for upper abdominal pathology ...

African Journals Online (AJOL)

CT scan contributes to the final diagnosis in organ-specific upper- abdominal ..... planes to encase the celiac axis and superior mesenteric artery, the superior ... men, and possibly pelvis, to evaluate for extrahepatic disease.15 In one.

Membrane-based ethylene/ethane separation: The upper bound and beyond

KAUST Repository

Rungta, Meha

2013-08-02

Ethylene/ethane separation via cryogenic distillation is extremely energy-intensive, and membrane separation may provide an attractive alternative. In this paper, ethylene/ethane separation performance using polymeric membranes is summarized, and an experimental ethylene/ethane polymeric upper bound based on literature data is presented. A theoretical prediction of the ethylene/ethane upper bound is also presented, and shows good agreement with the experimental upper bound. Further, two ways to overcome the ethylene/ethane upper bound, based on increasing the sorption or diffusion selectivity, is also discussed, and a review on advanced membrane types such as facilitated transport membranes, zeolite and metal organic framework based membranes, and carbon molecular sieve membranes is presented. Of these, carbon membranes have shown the potential to surpass the polymeric ethylene/ethane upper bound performance. Furthermore, a convenient, potentially scalable method for tailoring the performance of carbon membranes for ethylene/ethane separation based on tuning the pyrolysis conditions has also been demonstrated. © 2013 American Institute of Chemical Engineers.

The Role of External Environment in Upper Echelons Theory

DEFF Research Database (Denmark)

Yamak, Sibel; Nielsen, Sabina; Escribá-Esteve, Alejandro

2014-01-01

and industrial organization theories, a cross-level conceptual model outlining the direct, mediating, and moderating effects of the external environment on upper echelons is developed. This review distinguishes between industry and institutional levels of analysis and three types of environmental characteristics......Upper echelons research has largely focused on the antecedents and consequences of top management teams (TMTs) from the team and firm levels of analysis. This paper reviews empirical research on TMTs with a specific emphasis on the role of the external environment. Applying institutional...

Germanium and uranium in coalified wood from upper Devonian black shale

Energy Technology Data Exchange (ETDEWEB)

Breger, I A; Schopf, J M

1955-02-01

Spectrographic analyses were performed on carbonaceous material and shale samples from the Chattanooga shale in Tennessee and the Cleveland member of the Ohio shale in Ohio with particular emphasis on U and Ge. Semiquantitative analyses for 29 elements (Fe, Si, Ge, Al, Ca, V, Ni, U, Mg, Cu, Ti, Cr, Mo, Na, Sr, B, Y, Pb, Ba, Co, Sn, Zr, Mn, Zn, Yb, Ga, Sc, Be) were performed on both ash specimens and whole sample. The analyses showed unusually high percentages of Ge (1 to 5%) U (0.1 to 1%), V (1 to 5%), and Ni (0.1 to 1%) in the ash of coal from the Chattanooga and Ohio shales. Quantitative chemical analysis for U, Ge, V, and Ni in the whole coal and ash were done to check the results of the semiquantitative analyses. Ash content from the proximate analyses indicated that the coal samples tested were similar to vitrain in ash percentage. Because of the unusually high percentages of U and Ge and the low ash of the coals tested, the author felt that the U and Ge might be associated wire also observed with lower radiation doses (200 and 400 rad).

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.

The Role of Terrestrial N along a Frasnian/Famennian Boundary Transect of the Appalachian Basin

Science.gov (United States)

Tuite, Michael; Macko, Stephen

2010-05-01

A causal link between the Late Devonian emergence of forest ecosystems and episodic black shale deposition has been proposed by several authors. Most attribute increases in epicontinental basin productivity to elevated rates of terrestrial phosphorus weathering facilitated by the co-evolution of root systems and soils. Two reasons to suspect that an increase in the P weathering flux was not the primary cause of organic-rich shale deposition are as follows. First, most Late Devonian black shales were deposited during sea level transgressions, periods when riverine fluxes of sediment and mineral nutrients such as P to marine basins were diminished. Second, Late Devonian forests were restricted to warm, moist lowlands where P was sequestered in soils as inorganic, occluded forms. However, the export flux of reactive N from these forests to adjacent epeiric seas by riverine and atmospheric deposition was enhanced by the warm, wet climate and expanding areal extent of forests. Abundant terrestrial reactive N primed the marine eutrophication pump by extending the residence time of P in the photic zone, permitting extensive growth of primary biomass. The consequent flux of organic matter to the sea floor created anoxic bottom waters that, in turn, allowed for the remobilization of P into the water column. Based on abundance and isotopic analyses of organic and inorganic C, N, P, and S from terrestrial and marine environments within and adjacent to the Late Devonian Appalachian Basin, this latter scenario is supported.

Recognition of depositional sequences and stacking patterns, Late Devonian (Frasnian) carbonate platforms, Alberta basin

Energy Technology Data Exchange (ETDEWEB)

Anderson, J.H.; Reeckmann, S.A.; Sarg, J.F.; Greenlee, S.M.

1987-05-01

Six depositional sequences bounded by regional unconformities or their correlative equivalents (sequence boundaries) have been recognized in Late Devonian (Frasnian) carbonate platforms in the Alberta basin. These sequences consist of a predictable vertical succession of smaller scale shoaling-upward cycles (parasequences). Parasequences are arranged in retrogradational, aggradational, and progradational stacking patterns that can be modeled as a sediment response to relative changes in sea level. Sequence boundaries are recognized by onlap onto underlying shelf or shelf margin strata. This onlap includes shelf margin wedges and deep marine onlap. In outcrop sections shelf margin wedges exhibit an abrupt juxtaposition of shallow water facies over deeper water deposits with no gradational facies changes at the boundaries. High on the platform, subaerial exposure fabrics may be present. The shelf margin wedges are interpreted to have formed during lowstands in sea level and typically exhibit an aggradational stacking pattern. On the platform, two types of sequences are recognized. A type 1 cycle occurs where the sequence boundary is overlain by a flooding surface and subsequent parasequences exhibit retrogradational stacking. In a type 2 cycle the sequence boundary is overlain by an aggradational package of shallow water parasequences, followed by a retrogradational package. These two types of sequences can be modeled using a sinusoidal eustatic sea level curve superimposed on thermo-tectonic subsidence.

The Hunsrück biota: A unique window into the ecology of Lower Devonian arthropods.

Science.gov (United States)

Rust, Jes; Bergmann, Alexandra; Bartels, Christoph; Schoenemann, Brigitte; Sedlmeier, Stephanie; Kühl, Gabriele

2016-03-01

The approximately 400-million-year old Hunsrück biota provides a unique window into Devonian marine life. Fossil evidence suggests that this biota was dominated by echinoderms and various classes of arthropods, including Trilobita, stem lineage representatives of Euarthropoda, Chelicerata and Eucrustacea, as well as several crown group Chelicerata and Eucrustacea. The Hunsrück biota's exceptional preservation allows detailed reconstructions and description of key-aspects of its fauna's functional morphologies thereby revealing modes of locomotion, sensory perception, and feeding strategies. Morphological and stratigraphic data are used for a critical interpretation of the likely habitats, mode of life and nutritional characteristics of this diverse fauna. Potential predators include pycnogonids and other chelicerates, as well as the now extinct stem arthropods Schinderhannes bartelsi, Cambronatus brasseli and Wingertshellicus backesi. Mainly the deposit feeding Trilobita, Marrellomorpha and Megacheira, such as Bundenbachiellus giganteus, represents scavengers. Possibly, opportunistic scavenging was also performed by the afore-mentioned predators. Most of the studied arthropods appear to have been adapted to living in relatively well-illuminated conditions within the photic zone. Fossil evidence for associations amongst arthropods and other classes of metazoans is reported. These associations provide evidence of likely community structures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Palaeoceanographic controls on geochemical characteristics of organic-rich Exshaw mudrocks: role of enhanced primary production

Energy Technology Data Exchange (ETDEWEB)

Caplan, M.L.; Bustin, R.M. [University of British Columbia, Vancouver (Canada). Dept. of Earth and Ocean Sciences

1999-07-01

Organic-rich source rocks have generally been attributed to enhanced preservation of organic matter under anoxic bottom waters. Here geochemical analysis of kerogen and whole rock samples of organic-rich (lithofacies B{sub 1}) and organic-lean (lithofacies B{sub 2}) laminated mudrocks of the Devonian-Carboniferous Exshaw Formation, Alberta, highlight the importance of primary production in governing the quantity and quality of organic matter. Lower Si/Al, K/Al, Ti/Al and quartz/clay ratios in lithofacies B{sub 2}, similar maceral types and the laminated fabric of the two lithofacies indicate that the quality and quantity of organic matter are not related to grain size, redox or organic matter source changes. High Total Organic Carbon (TOC) and Hydrogen Index (HI), low Oxidation Index (Ox.I. ratio of oxygen functional groups to aliphatic groups derived by FTIR), lighter {delta}{sup 15}N{sub tot} and heavier {delta}{sup 13}C{sub org} isotopes indicate that kerogen of lithofacies B{sub 1} accumulated during periods of high organic-carbon production and delivery of relatively fresh, labile, well-preserved organic matter to the sea floor. In contrast, low TOC, HI, high Ox.I., heavier {delta}{sup 15}N{sub tot} and lighter {delta}{sup 13}C{sub org} isotopes indicate low primary productivity and delivery, high recycling and poor preservation of organic matter during accumulation of lithofacies B{sub 2}. (author)

New porcellioidean gastropods from early Devonian of Royal Creek area, Yukon Territory, Canada, with notes on their early phylogeny

Science.gov (United States)

Fryda, J.; Blodgett, R.B.; Lenz, A.C.; Manda, S.

2008-01-01

This paper presents a description of new gastropods belonging to the superfamily Porcellioidea (Vetigastropoda) from the richly diverse Lower Devonian gastropod fauna of the Road River Formation in the Royal Creek area, Yukon Territory. This fauna belongs to Western Canada Province of the Old World Realm. The Pragian species Porcellia (Porcellia) yukonensis n. sp. and Porcellia (Paraporcellia) sp. represent the oldest presently known members of subgenera Porcellia (Porcellia) and Porcellia (Paraporcellia). Their simple shell ornamentation fits well with an earlier described evolutionary trend in shell morphology of the Porcellinae. Late Pragian to early Emsian Perryconcha pulchra n. gen. and n. sp. is the first member of the Porcellioidea bearing a row of tremata on adult teleoconch whorls. The occurrence of this shell feature in the Porcellioidea is additional evidence that the evolution of the apertural slit was much more complicated than has been proposed in classical models of Paleozoic gastropod evolution. Copyright ?? 2008, The Paleontological Society.

Distribution of Total and Organic Mercury in Superficial Soils in the Upper Manzanares River Watershed, Sucre State, Venezuela

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Yahsé Rojas Challa

2008-01-01

Full Text Available Total and organic mercury contents were determined from samples of surface soils (0-5 cm, sieved at ≤ 63µm, collected from 10 different locations in the upper Manzanares River watershed, using cold vapor atomic absorption spectroscopy. Methylmercury was determined using a HPLC-UV detector. The mean total mercury concentration was 1.3 μg.g-1, a value permitted by the Canadian environment quality guidelines for farming soils, but high for European standards. Using certified reference materials, we verified that a modification of the method described by Qian et al. (2000 was effective for organic mercury extraction, with a recovery of 92.17% for DORM-2 and 92.11% for TORT-2. This modified method was applied to soil samples, obtaining concentrations of 0.5-1.0 μg.g-1 of organic mercury. The parameters for determining methylmercury using HPLC-UV were optimized; the best results were obtained with a 4.6 mm x 25 cm Zorbax CN column, with a mobile phase of 70/30 V/V of methanol: ammonium acetate 0.05 mol.l-1, with a flow rate of 0.5 ml.min-1; the methylmercury was detected at 4.99 min retention time. Methylmercury was not found in the soil samples. Using the certified reference material we proved that the method used produced reliable results. The analysis confirmed the existence of mercury in this farming area.

Paleozoic unconformities favorable for uranium concentration in northern Appalachian basin

International Nuclear Information System (INIS)

Dennison, J.M.

1986-01-01

Unconformities can redistribute uranium from protore rock as ground water moves through poorly consolidated strata beneath the erosion surface, or later moves along the unconformity. Groundwater could migrate farther than in present-day lithified Paleozoic strata in the Appalachian basin, now locally deformed by the Taconic and Allegheny orogenies. Several paleoaquifer systems could have developed uranium geochemical cells. Sandstone mineralogy, occurrences of fluvial strata, and reduzate facies are important factors. Other possibilities include silcrete developed during desert exposure, and uranium concentrated in paleokarst. Thirteen unconformities are evaluated to determine favorable areas for uranium concentration. Cambrian Potsdam sandstone (New York) contains arkoses and possible silcretes just above crystalline basement. Unconformities involving beveled sandstones and possible fluvial strata include Cambrian Hardyston sandstone (New Jersey), Cambrian Potsdam Sandstone (New York), Ordovician Oswego and Juniata formations (Pennsylvania and New York), Silurian Medina Group (New York), and Silurian Vernon, High Falls, and Longwood formations (New York and New Jersey). Devonian Catskill Formation is beveled by Pennsylvanian strata (New York and Pennsylvania). The pre-Pennsylvanian unconformity also bevels Lower Mississippian Pocono, Knapp, and Waverly strata (Pennsylvania, New York, and Ohio), truncates Upper Mississippian Mauch Chunk Formation (Pennsylvania), and forms paleokarst on Mississippian Loyalhanna Limestone (Pennsylvania) and Maxville Limestone (Ohio). Strata associated with these unconformities contain several reports of uranium. Unconformities unfavorable for uranium concentration occur beneath the Middle Ordovician (New York), Middle Devonian (Ohio and New York), and Upper Devonian (Ohio and New York); these involve marine strata overlying marine strata and probably much submarine erosion

Organic geochemistry: Effects of organic components of shales on adsorption: Progress report

International Nuclear Information System (INIS)

Ho, P.C.

1988-11-01

The Sedimentary Rock Program at the Oak Ridge National Laboratory is investigating shale to determine its potential suitability as a host rock for the disposal of high-level radioactive wastes (HLW). The selected shales are Upper Dowelltown, Pierre, Green River Formation, and two Conasauga (Nolichucky and Pumpkin Valley) Shales, which represent mineralogical and compositional extremes of shales in the United States. According to mineralogical studies, the first three shales contain 5 to 13 wt % of organic matter, and the two Conasauga Shales only contain trace amounts (2 wt %) of organic matter. Soxhlet extraction with chloroform and a mixture of chloroform and methanol can remove 0.07 to 5.9 wt % of the total organic matter from these shales. Preliminary analysis if these organic extracts reveals the existence of organic carboxylic acids and hydrocarbons in these samples. Adsorption of elements such as Cs(I), Sr(II) and Tc(VII) on the organic-extracted Upper Dowelltown, Pierre, green River Formation and Pumpkin Valley Shales in synthetic groundwaters (simulating groundwaters in the Conasauga Shales) and in 0.03-M NaHCO 3 solution indicates interaction between each of the three elements and the organic-extractable bitumen. 28 refs., 8 figs., 10 tabs

Complete upper urinary tract obstruction caused by penetrating ...

African Journals Online (AJOL)

Complete upper urinary tract obstruction caused by penetrating pellet injury of the ureter. M.T. Gulpinar, S.K. Keskin, A Yildirim, T Caskurlu. Abstract. Ureteral injuries due to gunshots are tend to be misdiagnosed because of concomitant vascular and intraabdominal organ wounds. Our case is a 23-year old man who was ...

Andoma segment of southeastern margin of fennoscandian shield: Structure and evolution

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Kolodyazhny, S. Yu.; Baluev, A. S.; Terekhov, E. N.

2016-07-01

The components of deformation related to endogenic (tectonic) and exogenic (glaciotectonic, gravitational sliding) factors are considered in the sedimentary platform cover by a study of Andoma dislocations in the Upper Devonian sedimentary rocks of the Lake Onega district. These structures are localized in the eponymous segment of the southeastern margin of the Fennoscandian (Baltic) Shield; indications of high tectonic activity are noted along this margin. As has been shown by a structural study, the development of the Andoma structure is caused by long-term (Late Devonian-Quaternary) multistage deformations related to tectonic factors and, to a lesser degree, glaciotectonics. The consecutive stages of synsedimentation normal faulting and landsliding, bedding-plane gliding, various forms of shear flow in a regime of transpression, glaciotectonic thrusting, and neotectonic transpression are recognized in the deformation history.

Iron in the Middle Devonian aquifer system and its removal at Võru County water treatment plants, Estonia

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Mariina Hiiob

2012-08-01

Full Text Available Groundwater abstracted from the Middle Devonian aquifer system is the main source of drinking water in South Estonia. High iron and manganese concentrations in groundwater are the greatest problems in this region. The total iron concentrations up to 16 mg L–1 are mainly caused by a high Fe2+ content in water, pointing to the dominance of reducing conditions in the aquifer system. A pilot study was carried out to estimate the effectiveness of 20 groundwater purification plants with eight different water treatment systems (aeration combined with Manganese Greensand, Birm, Nevtraco, Hydrolit-Mn, Magno-Dol and quartz sand filters in Võru County. The results demonstrate that in most cases the systems with pre-aeration effectively purify groundwater from iron, but only 13 out of 20 water treatment plants achieved a reduction of iron concentration to the level fixed in drinking water requirements (0.2 mg L–1. Manganese content decreased below the maximum allowed concentration in only 25% of systems and in cases where the filter media was Birm or quartz sand and pre-oxidation was applied. The study showed that the high level of iron purification does not guarantee effective removal of manganese.

Infiltration-driven metamorphism, New England, USA: Regional CO2 fluxes and implications for Devonian climate and extinctions

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Stewart, E. M.; Ague, Jay J.

2018-05-01

We undertake thermodynamic pseudosection modeling of metacarbonate rocks in the Wepawaug Schist, Connecticut, USA, and examine the implications for CO2 outgassing from collisional orogenic belts. Two broad types of pseudosections are calculated: (1) a fully closed-system model with no fluid infiltration and (2) a fluid-buffered model including an H2O-CO2 fluid of a fixed composition. This fluid-buffered model is used to approximate a system open to infiltration by a water-bearing fluid. In all cases the fully closed-system model fails to reproduce the observed major mineral zones, mineral compositions, reaction temperatures, and fluid compositions. The fluid-infiltrated models, on the other hand, successfully reproduce these observations when the XCO2 of the fluid is in the range ∼0.05 to ∼0.15. Fluid-infiltrated models predict significant progressive CO2 loss, peaking at ∼50% decarbonation at amphibolite facies. The closed-system models dramatically underestimate the degree of decarbonation, predicting only ∼15% CO2 loss at peak conditions, and, remarkably, global warming, sea level rise, and, perhaps, extinction in the mid- to late-Devonian.

ORIGINAL ARTICLE ORIG ORIG CT for upper abdominal pathology ...

African Journals Online (AJOL)

ORIG. 14. SA JOURNAL OF RADIOLOGY • March 2007. ORIG. Abstract. Background. Current practice at our institution for routine abdominal. CT includes coverage from the diaphragm to the symphysis pubis and therefore includes pelvic organs. Limited upper abdominal imaging exists in other modalities, and tailoring the ...

Life history of the stem tetrapod Acanthostega revealed by synchrotron microtomography.

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Sanchez, Sophie; Tafforeau, Paul; Clack, Jennifer A; Ahlberg, Per E

2016-09-15

The transition from fish to tetrapod was arguably the most radical series of adaptive shifts in vertebrate evolutionary history. Data are accumulating rapidly for most aspects of these events, but the life histories of the earliest tetrapods remain completely unknown, leaving a major gap in our understanding of these organisms as living animals. Symptomatic of this problem is the unspoken assumption that the largest known Devonian tetrapod fossils represent adult individuals. Here we present the first, to our knowledge, life history data for a Devonian tetrapod, from the Acanthostega mass-death deposit of Stensiö Bjerg, East Greenland. Using propagation phase-contrast synchrotron microtomography (PPC-SRμCT) to visualize the histology of humeri (upper arm bones) and infer their growth histories, we show that even the largest individuals from this deposit are juveniles. A long early juvenile stage with unossified limb bones, during which individuals grew to almost final size, was followed by a slow-growing late juvenile stage with ossified limbs that lasted for at least six years in some individuals. The late onset of limb ossification suggests that the juveniles were exclusively aquatic, and the predominance of juveniles in the sample suggests segregated distributions of juveniles and adults at least at certain times. The absolute size at which limb ossification began differs greatly between individuals, suggesting the possibility of sexual dimorphism, adaptive strategies or competition-related size variation.

Evidence of an upper ordovician thermo-metamorphic event in the SW-Corner of the Cantabrian Mountains (N-Spain

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Krumm, S.

1992-12-01

Full Text Available According to Illite «crystallinity» (IC data, the metamorphic evolution of the SW Cantabrian Mountains took place in several steps. After a Precambrian deformation with accompanying low-grade metamorphism a thermal event during the Upper Ordovician affected the Cambro-Ordovician sediments. This event is marked by anchizonal IC values in the Pre-Silurian sequence contrasting the diagenetic data obtained from Siluro-Devonian rocks.Apparently, the metamorphic history in that part of the Cantabrian Mountains ended during the Late Ordovician, a Hercynian metamorphism cannot be proven conclusively.Segun la cristalinidad de Illita (IC la evolución metamórfica de la zona sudoeste de la Cordillera Cantábrica tuvo lugar en varias etapas. Siguiendo una deformación precámbrica con un metamorfismo de bajo grado, un evento térmico durante el Ordovícico Superior afecto a la secuencia Cambro-Ordovícica. Este evento esta marcado en las rocas pre-Silúricas por valores de IC indicando la anchizona. Estos datos contrastan con valores obtenidos de la secuencia Siluro-Devónica, que son característicos de la diagénesis.Aparentemente, la evolución metamórfica del sudoeste de la Cordillera Cantábrica termino durante el Ordovícico, un metamorfismo Hercínico no pudo ser comprobado.

Characteristics of the Late Devonian Tsagaan Suvarga Cu-Mo deposit, Southern Mongolia

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Tungalag, Naidansuren; Jargalan, Sereenen; Khashgerel, Bat-Erdene; Mijiddorj, Chuluunbaatar; Kavalieris, Imants

2018-05-01

The Late Devonian Tsagaan Suvarga deposit (255 Mt at 0.55% Cu, 0.02% Mo) is located on the NW margin of the Tsagaan Suvarga Complex (TSC), which extends ENE over 15 × 10 km and comprises mainly medium-grained equigranular hornblende-biotite quartz monzonite and monzodiorite. Distinct mineralized intrusions are inferred from distribution of Cu-Mo mineralization but are not clearly discernible. The Tsagaan Suvarga Complex is a window within Carboniferous volcanic and sedimentary rocks, and wall rocks to the TSC are not known or exposed in the nearby district. Whole-rock analyses and Sr-Nd isotopes, 87Sr/86Sr0 = 0.7027 to 0.7038 (n = 12) and ɛNd0 = + 4.26 to + 2.77 (n = 12), show that the granitoids are subduction-related I-type, high K-calc-alkaline to shoshonitic series and derived from a mantle source. They exhibit fractionated light rare earth elements, without depleted Eu and depleted middle heavy rare earth elements and Y, typical of oxidized, fertile porphyry magmatic suites. Early porphyry-style quartz veins include A- and B-type. Molybdenite occurs in monomineralic veins (1-5 mm) or A veins. Copper mineralization occurs mainly as chalcopyrite and subordinate bornite, disseminated and associated with quartz-muscovite veins. Pyrite (vol%) content is less than chalcopyrite and bornite combined. Deep oxidation to about 50 m depth has formed zones of malachite and covellite in late fractures. The most important alteration is actinolite-biotite-chlorite-magnetite replacing hornblende and primary biotite. Quartz-K-feldspar alteration is minor. Late albite replaces primary K-feldspar and enhances sodic rims on plagioclase crystals. Quartz-muscovite (or sericitic alteration) overprints actinolite-biotite and porphyry-type quartz veins. Field observations and petrographic studies suggest that the bulk of the chalcopyrite-bornite mineralization at the Tsagaan Suvarga formed together with coarse muscovite alteration.

National Uranium Resource Evaluation, Scranton Quadrangle, Pennsylvania, New York, and New Jersey

International Nuclear Information System (INIS)

Baillieul, T.A.; Indelicato, G.J.; Penley, H.M.

1980-11-01

Reconnaissance and detailed geologic and radiometric investigations were conducted throughout the Scranton Quadrangle, Pennsylvania, New York, and New Jersey, to evaluate uranium favorability using National Uranium Resource Evaluation criteria. Surface and subsurface studies were augmented by aerial radiometric, hydrogeochemical and stream sediment reconnaissance, and emanometry surveys. Results of the investigations indicate four environments favorable for uranium deposits: In the Precambrian metamorphic terrain of the Reading Prong, magmatic-hydrothermal and anatectic deposits may occur in the northwestern massif; contact metasomatic deposits may occur in a portion of the southeastern massif. The alluvial-fan environment at the base of the Upper Devonian Catskill Formation appears favorable for deposits in peneconcordant channel controlled sandstones. Seven environments are considered unfavorable for uranium deposits: the southeastern massif of the Reading Prong, exclusive of that portion denoted as a favorable contact metasomatic environment; the lower Paleozoic sedimentary units; the Beemerville nepheline syenite complex; the Upper Devonian Catskill Formation, exclusive of the favorable basal alluvial-fan facies; Mississippian and Pennsylvanian units; and peat bogs. Two environments were not evaluated: the Spechty Kopf Formation, because of paucity of exposure and lack of sufficient data; and the Newark Basin, because of cultural density and inadequate subsurface information

[Effects of grazing disturbance on soil active organic carbon in mountain forest-arid valley ecotone in the upper reaches of Minjiang River].

Science.gov (United States)

Liu, Shan-Shan; Zhang, Xing-Hua; Gong, Yuan-Bo; Li, Yuan; Wang, Yan; Yin, Yan-Jie; Ma, Jin-Song; Guo, Ting

2014-02-01

Effects of grazing disturbance on the soil carbon contents and active components in the four vegetations, i.e., artificial Robinia pseudoacacia plantation, artificial poplar plantation, Berberis aggregate shrubland and grassland, were studied in the mountain forest-arid valley ecotone in the upper Minjiang River. Soil organic carbon and active component contents in 0-10 cm soil layer were greater than in 10-20 cm soil layer at each level of grazing disturbance. With increasing the grazing intensity, the total organic carbon (TOC), light fraction organic carbon (LFOC), particulate organic carbon (POC) and easily oxidized carbon (LOC) contents in 0-10 cm soil layer decreased gradually in the artificial R. pseudoacacia plantation. The LFOC content decreased, the POC content increased, and the TOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the artificial poplar plantation. The POC content decreased, and the TOC, LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the B. aggregate shrubland. The POC and TOC contents decreased, and the LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the grassland. The decreasing ranges of LOC, LFOC and POC contents were 0.1-7.9 times more than that of TOC content. There were significant positive relationships between TOC and LOC, LFOC and POC, suggesting that the active organic carbon components could reflect the change of soil total carbon content.

The nature of porosity in organic-rich mudstones of the Upper Jurassic Kimmeridge Clay Formation, North Sea, offshore United Kingdom

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Fishman, Neil S.; Hackley, Paul C.; Lowers, Heather; Hill, Ronald J.; Egenhoff, Sven O.; Eberl, Dennis D.; Blum, Alex E.

2012-01-01

Analyses of organic-rich mudstones from wells that penetrated the Upper Jurassic Kimmeridge Clay Formation, offshore United Kingdom, were performed to evaluate the nature of both organic and inorganic rock constituents and their relation to porosity in this world-class source rock. The formation is at varying levels of thermal maturity, ranging from immature in the shallowest core samples to mature in the deepest core samples. The intent of this study was to evaluate porosity as a function of both organic macerals and thermal maturity. At least four distinct types of organic macerals were observed in petrographic and SEM analyses and they all were present across the study area. The macerals include, in decreasing abundance: 1) bituminite admixed with clays; 2) elongate lamellar masses (alginite or bituminite) with small quartz, feldspar, and clay entrained within it; 3) terrestrial (vitrinite, fusinite, semifusinite) grains; and 4) Tasmanites microfossils. Although pores in all maceral types were observed on ion-milled surfaces of all samples, the pores (largely nanopores with some micropores) vary as a function of maceral type. Importantly, pores in the macerals do not vary systematically as a function of thermal maturity, insofar as organic pores are of similar size and shape in both the immature and mature Kimmeridge rocks. If any organic pores developed during the generation of hydrocarbons, they were apparently not preserved, possibly because of the highly ductile nature of much of the rock constituents of Kimmeridge mudstones (clays and organic material). Inorganic pores (largely micropores with some nanopores) have been observed in all Kimmeridge mudstones. These pores, particularly interparticle (i.e., between clay platelets), and intraparticle (i.e., in framboidal pyrite, in partially dissolved detrital K-feldspar, and in both detrital and authigenic dolomite) are noteworthy because they compose much of the observable porosity in the shales in both

The Early Devonian eurypterid Grossopterus overathi (Gross, 1933 from Overath, Germany

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J. A. Dunlop

2002-01-01

Full Text Available The holotype and only known specimen of the eurypterid (Chelicerata: Eurypterida Grossopterus overathi (Gross, 1933 from the Early Devonian (Siegennian of Overath, north-west Germany is redescribed. Based on comparisons with other eurypterid taxa we interpret G. overathi as having a well-preserved type B genital appendage, which exhibits two apomorphic character states: (1 a furca fused into a single, spatulate plate and (2 marginal serrations near the distal end of the appendage. Grossopterus is assigned to the family Hughmilleriidae, but its carapace resembles that of the larger Slimonia acuminata (Salter, 1856 (Slimoniidae. A provisional phylogenetic analysis resolves Grossopterus as the sister group of (Slimonia + Pterygotoidea. The large pterygotids, in particular, have been suggested as significant predators on early vertebrates and hypotheses about eurypterid-fish co-evolution are reviewed, in particular Romer's proposal that dermal armour in fish evolved in response to eurypterid predation. Der Holotyp – das einzig bekannte Exemplar – des Eurypteriden (Chelicerata: Eurypterida Grossopterus overathi (Gross, 1933 aus dem frühen Devon (Siegennian von Overath im nordwestlichen Deutschland wird wieder beschrieben. Basierend auf Vergleichen mit anderen Eurypteriden-Taxa interpretieren wir G. overathi als Träger eines Typ B-Anhanges, wobei zwei apomorphe Merkmalszustände vorliegen: (1 die Furca ist zu einer einzigen, spatelförmigen Platte verschmolzen, und (2 der Seitenrand nahe des distalen Endes des Genitalanhanges ist gezähnt. Grossopterus wird zur Familie der Hughmilleriidae gestellt, aber der prosomale Dorsalschild ähnelt der größeren Slimonia acuminata (Salter, 1856 (Slimoniidae. Eine vorläufige phylogenetische Analyse zeigt Grossopterus als Schwesteruppe von (Slimonia + Pterygotoidea auf. Besonders die großen Pterygotiden wurden als signifikante Prädatoren von frühen Vertebraten gehandelt, und Hypothesen zur Eurypteriden

Sedimentology, organic matter and diagenesis of fishscale shales in the molasse basin of upper Austria (Upper Eocene - Lower Oligocene); Sedimentologie, organisches Material und Diagenese des Fischschiefers im oberoesterreichischen Molasse-Becken (Obereozaen - Unteroligozaen)

Energy Technology Data Exchange (ETDEWEB)

Schulz, H.M. [Inst. fuer Geologie und Palaeontologie der TU Clausthal, Clausthal-Zellerfeld (Germany); Sachsenhofer, R.F.; Bechtel, A. [Inst. fuer Geowiss. der Montanuniversitaet Leoben, Wien (Austria); Wagner, L.; Polesny, H.

2002-07-01

Fishscale shales (Schoeneck Formation) is an important parent rock of petroleum in prealpine molasse. Two different formation models are discussed, i.e. deposition and accumulation of organic matter (a) in a stagnating basin and (b) in a buoyancy zone. Both models were derived from samples, but they provide no information on the lithological and geochemical characteristics of complete fishscale shale sequences. This investigation focused on the vertical and lateral sedimentary development and the diagenetic changes of organic matter in the fishscale shales of upper Austria. Additionally, organic-geochemical data were used for validating the two deposition models. [German] Der Fischschiefer (Schoeneck Formation) stellt ein wichtiges Erdoelmuttergestein der alpinen Vorlandmolasse der. Waehrend seiner Ablagerung im Obereozaen(?)-Unteroligozaen wurde infolge der alpinen Orogenese die Paratethys von der Tethys abgetrennt und der Wasseraustausch zur Tethys eingeschraenkt. Gleichzeitig stroemten kalte Wassermassen ueber die polnische Senke in die Paratethys. Die Ablagerung der organisch-reichen Sedimente wird auf diese veraenderte palaeo-ozeanographische Situation zurueckgefuehrt. Zwei unterschiedliche Modelle werden fuer deren Bildung diskutiert: Ablagerung und Akkumulation von organischem Material in (a) einem stagnierenden Becken oder (b) in einer Auftriebszone. Die bislang diskutierten Modelle beruhen auf Ergebnissen vereinzelter Proben. Jedoch liegen keine Informationen hinsichtlich der lithologischen und geochemischen Charakteristika vollstaendiger Fischschiefer-Abfolgen vor. Es ist das Ziel dieses Beitrages, die vertikale und laterale sedimentaere Entwicklung, sowie die diagenetischen Veraenderungen des organischen Materials im Fischschiefer in Oberoesterreich vorzustellen. Zusaetzlich werden organisch-geochemische Daten eingesetzt, um die beiden vorgestellten Ablagerungsmodelle zu ueberpruefen. (orig.)

Microbes in the upper atmosphere and unique opportunities for astrobiology research.

Science.gov (United States)

Smith, David J

2013-10-01

Microbial taxa from every major biological lineage have been detected in Earth's upper atmosphere. The goal of this review is to communicate (1) relevant astrobiology questions that can be addressed with upper atmosphere microbiology studies and (2) available sampling methods for collecting microbes at extreme altitudes. Precipitation, mountain stations, airplanes, balloons, rockets, and satellites are all feasible routes for conducting aerobiology research. However, more efficient air samplers are needed, and contamination is also a pervasive problem in the field. Measuring microbial signatures without false positives in the upper atmosphere might contribute to sterilization and bioburden reduction methods for proposed astrobiology missions. Intriguingly, environmental conditions in the upper atmosphere resemble the surface conditions of Mars (extreme cold, hypobaria, desiccation, and irradiation). Whether terrestrial microbes are active in the upper atmosphere is an area of intense research interest. If, in fact, microbial metabolism, growth, or replication is achievable independent of Earth's surface, then the search for habitable zones on other worlds should be broadened to include atmospheres (e.g., the high-altitude clouds of Venus). Furthermore, viable cells in the heavily irradiated upper atmosphere of Earth could help identify microbial genes or enzymes that bestow radiation resistance. Compelling astrobiology questions on the origin of life (if the atmosphere synthesized organic aerosols), evolution (if airborne transport influenced microbial mutation rates and speciation), and panspermia (outbound or inbound) are also testable in Earth's upper atmosphere.

Comparative organic petrology of interlayered sandstones, siltstones, mudstones and coals in the Upper Carboniferous Ruhr basin, northwest Germany, and their thermal history and methane generation

Energy Technology Data Exchange (ETDEWEB)

Scheidt, G.; Littke, R. (Harress Geotechnik GmbH, Floersheim (Germany, F.R.))

1989-01-01

In the coal-mining Ruhr-area, Upper Carboniferous rocks consist of interlayered sandstones, siltstones, mudstones and coals. They were deposited in a tropical, paralic environment where alternating fluvial sedimentation, occasional marine ingressions, and swamp growth resulted in an irregular cyclic succession. The total sedimentary package contains on an average 6 Vol.% of organic manner. About 70 Vol. % of the organic matter occurs in coal seams, the rest as dispersed organic matter in clastic rocks. The organic matter is autochthonous in the coals and allochthonous in associated sandstones and siltstones. It consists of about 70% vitrinite, 20% inertinite, and 10% liptinite. The overall maceral group composition is the same for coals and dispersed organic matter. This surprising similarity is caused by a nearly exclusive input of land-plant derived organic matter to swamps and fluvial systems and a similar degree of preservation. Highest average liptinite contents were found in unrooted mudstones, highest average inertinite contents in coarse-grained siltstones and highest average vitrinite percentages in sandstones. Maturities of the sediments studied are well within the hydrocarbon generation window, e.g. vitrinite reflectivities range from 0.6% to 1.6%. Reflectivities measured on dispersed particles in clastic rocks are similar to those measured in coal seams. Calculations of the amount of methane generated indicate that coal seams contributed more to the total hydrocarbon generation than dispersed organic matter. 51 refs., 13 figs.

U.S. Geological Survey 2013 assessment of undiscovered resources in the Bakken and Three Forks Formations of the U.S. Williston Basin Province

Science.gov (United States)

Gaswirth, Stephanie B.; Marra, Kristen R.

2014-01-01

The Upper Devonian Three Forks and Upper Devonian to Lower Mississippian Bakken Formations comprise a major United States continuous oil resource. Current exploitation of oil is from horizontal drilling and hydraulic fracturing of the Middle Member of the Bakken and upper Three Forks, with ongoing exploration of the lower Three Forks, and the Upper, Lower, and Pronghorn Members of the Bakken Formation. In 2008, the U.S. Geological Survey (USGS) estimated a mean of 3.65 billion bbl of undiscovered, technically recoverable oil resource within the Bakken Formation. The USGS recently reassessed the Bakken Formation, which included an assessment of the underlying Three Forks Formation. The Pronghorn Member of the Bakken Formation, where present, was included as part of the Three Forks assessment due to probable fluid communication between reservoirs. For the Bakken Formation, five continuous and one conventional assessment units (AUs) were defined. These AUs are modified from the 2008 AU boundaries to incorporate expanded geologic and production information. The Three Forks Formation was defined with one continuous and one conventional AU. Within the continuous AUs, optimal regions of hydrocarbon recovery, or “sweet spots,” were delineated and estimated ultimate recoveries were calculated for each continuous AU. Resulting undiscovered, technically recoverable resource estimates were 3.65 billion bbl for the five Bakken continuous oil AUs and 3.73 billion bbl for the Three Forks Continuous Oil AU, generating a total mean resource estimate of 7.38 billion bbl. The two conventional AUs are hypothetical and represent a negligible component of the total estimated resource (8 million barrels of oil).

The organic matter of the Potosi basin (Cordillera Oriental, Bolivia) during the Upper Cretaceous-Lower tertiary: stratigraphic and palaeogeographic data

Energy Technology Data Exchange (ETDEWEB)

Blanc-Valleron, M.M.; Rouchy, J.M. (Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France)); Schuler, M.; Rauscher, R. (Strasbourg-1 Univ., 67 (France)); Camoin, G. (Aix-Marseille-1 Univ., 13 - Marseille (France))

1994-12-01

Palynological and Rock-Eval pyrolysis studies of the Chaunaca and El Molino Fm (Santonian to Thanetian, Cordillera Oriental, Bolivia) indicate that some facies have economic significance as potential oil source rocks. The occurrence of Pediastrum and Azolla testify a lacustrine environment. In the Upper Molino, the environmental interpretation of an almost monospecific association of dinocysts is discussed. The presence of Apectodinium quinquelatum indicates that the age of the upper part of the Upper El Molino Fm is likely to be Upper Thanetian. (authors). 22 refs., 5 figs.

Bioerosion and encrustation: Evidences from the Middle ‒ Upper Jurassic of central Saudi Arabia

Science.gov (United States)

El-Hedeny, Magdy; El-Sabbagh, Ahmed; Al Farraj, Saleh

2017-10-01

The Middle ‒ Upper Jurassic hard substrates of central Saudi Arabia displayed considerable signs of bioerosion and encrustations. They include organic (oysters, other bivalves, gastropods, corals and brachiopods) and an inorganic carbonate hardground that marks the boundary between the Middle Jurassic Tuwaiq Mountain Limestone and the Upper Jurassic Hanifa Formation. Traces of bioerosion in organic substrates include seven ichnotaxa produced by bivalves (Gastrochaenolites Leymerie, 1842), polychaete annelids (Trypanites Mägdefrau, 1932; MaeandropolydoraVoigt, 1965 and CaulostrepsisClarke, 1908), sponges (Entobia Bronn, 1837), acrothoracican cirripedes (Rogerella Saint-Seine, 1951), gastropods (Oichnus Bromley, 1981) and probable ?Centrichnus cf. eccentricus. The encrusting epifauna on these substrates consist of several organisms, including oysters, serpulid worms, corals and foraminifera. In contrast, the carbonate hardground was only bioeroded by Gastrochaenolite, Trypanites and Entobia. Epibionts on this hardground include ;Liostrea Douvillé, 1904-type; oysters, Nanogyra nana Sowerby, 1822 and serpulids. In general, bioerosion and encrustation are less diversified in hardground than in organic substrates, indicating a long time of exposition of organic substrates with slow to moderate rate of deposition in a restricted marine environment. Both organic and inorganic commuinities are correlated with those of other equatorial, subtropical and temperate equivalents.

Design and preliminary evaluation of an exoskeleton for upper limb resistance training

Science.gov (United States)

Wu, Tzong-Ming; Chen, Dar-Zen

2012-06-01

Resistance training is a popular form of exercise recommended by national health organizations, such as the American College of Sports Medicine (ACSM) and the American Heart Association (AHA). This form of training is available for most populations. A compact design of upper limb exoskeleton mechanism for homebased resistance training using a spring-loaded upper limb exoskeleton with a three degree-of-freedom shoulder joint and a one degree-of-freedom elbow joint allows a patient or a healthy individual to move the upper limb with multiple joints in different planes. It can continuously increase the resistance by adjusting the spring length to train additional muscle groups and reduce the number of potential injuries to upper limb joints caused by the mass moment of inertia of the training equipment. The aim of this research is to perform a preliminary evaluation of the designed function by adopting an appropriate motion analysis system and experimental design to verify our prototype of the exoskeleton and determine the optimal configuration of the spring-loaded upper limb exoskeleton.

Time-temperature-burial significance of Devonian anthracite implies former great (approx.6.5 km) depth of burial of Catskill Mountains, New York

International Nuclear Information System (INIS)

Friedman, G.M.; Sanders, J.E.

1982-01-01

Specimens of coalified plant debris in Tully-correlative strata of the Gilboa Formation (uppermost Middle Devonian) within the eastern Catskill Mountains of New York State have been converted to anthracite having a vitrinite reflectance of 2.5%. This implies a level of organic metamorphism (LOM) of 16. The specimens are about 350 m.y. old; if 200 m.y. is taken as the duration of the time of exposure to the maximum geothermal temperature, then the LOM of 16 and other thermal indicators imply a maximum temperature of 190 0 C. Using a geothermal gradient of 26 0 C.km -1 (17 0 F.1,000 ft -1 ), a former depth of burial of 6.5 km is implied. Such former deep burial is not usually inferred for the Catskills, but it is consistent with the idea that the thick (about 6.4 km or 21,000 ft) Carboniferous strata of northeastern Pennsylvania formerly extended northeast far enough to bury the Catskills. The lack of metamorphism of the Paleozoic strata lying about 4.5 km beneath the Tully-correlative rocks and exposed in the adjacent Hudson Valley places low limits on the former geothermal gradient; this supports the concept of great depth of former burial of the Catskills. For example, 6.5 km of former burial and a geothermal gradient of 26 0 C.km -1 imply a temperature of 307 0 C for the base of the Paleozoic. By contrast, only 1 km of former burial requires a geothermal gradient of 170 0 C.km -1 , which would have subjected the base of the Paleozoic to a temperature of 955 0 GAMMA, which is far higher than the 600 to 650 0 C recently inferred for the Acadian-age metamorphism of the Taconic allochthon in southwestern Massachusetts and adjoining areas

The organic petrology and thermal maturity of Lower Carboniferous and Upper Devonian source rocks in the Liard Basin, at Jackfish Gap-Yohin Ridge and North Beaver River, northern Canada: Implications for hydrocarbon exploration

Energy Technology Data Exchange (ETDEWEB)

Potter, J. (Univ. of Newcastle-upon-Tyne (United Kingdom)); Richards, B.C.; Goodarzi, G. (Geological Survey, Calgary, Alberta (Canada))

Basinal shales of the Besa River Fm. have TOC values ranging from 1 to 4% and contain abundant type II, dominantly amorphous, kerogen of marine origin. Shales in the Yohin, Clausen, Prophet, and Golata Formations are of mixed maring and terrestrial origins and yield TOC values of 1 to 3%. Kerogen in the Golata and Yohin Formations are dominated by terrestrial components, while the Clausen and Flett kerogen comprises marine liptinites and bitumens. Kerogen from the deltaic Mattson shales at Jackfish Gap are types II and III, having mixed marine and terrestrial origins consistent with shallow, nearshore, subtidal environments. The coals are sapropelic and probably lacustrine in origin. Algal laminites associated with coals in the Upper Mattson have >10% TOC values, while non-laminite shales contain between 2 and 5% TOC. Comparable measured and calculated vitrinite reflectance data indicate that kerogen in the Lower Carboniferous at Jackfish Gap is mature. Kerogen in correlative formations in the subsurface at North Beaver River is more marine. Vitrinites are rate and oxidized, but four populations of bitumens are distinguished on the basis of relative reflectivity and morphological or petrophysical associations. Types A and B bitumens are primary and by-products of hydrocarbon generation from type II (algal and amorphous) kerogens. Correlations between depth and reflectance of bitumens A and B are very good. Vitrinite reflectance data calculated from bitumen reflectance measurements for the Besa River, Prophet, and Golata indicate that they are potential sources of catagenic gas. The Mattson kerogen is mature, oil and gas-prone.

Skarn-mineralized porphyry adakites in the Harlik arc at Kalatage, E. Tianshan (NW China): Slab melting in the Devonian-early Carboniferous in the southern Central Asian Orogenic Belt

Science.gov (United States)

Mao, Qigui; Yu, Mingjie; Xiao, Wenjiao; Windley, Brian F.; Li, Yuechen; Wei, Xiaofeng; Zhu, Jiangjian; Lü, Xiaoqiang

2018-03-01

The geodynamic control of mineralization in the accretionary evolution of the Central Asian Orogenic Belt (CAOB) has long been controversial. Here we report new field, geochemical and geochronological data on recently defined porphyry and skarn-type ore deposits (Devonian-Early Carboniferous) in the Kalatage area in the middle of the Harlik-Dananhu arc, Eastern Tianshan, NW China in the southern CAOB, with the aim of better understanding the accretionary tectonics and genesis of porphyry and skarn-type mineralization. The Yudai porphyry Cu-(Au) deposits and the Xierqu skarn Cu-Fe-(Au) deposits are closely associated with Middle Devonian adakitic diorite porphyries (382-390 Ma), which are calc-alkaline and characterized by high Na2O/K2O ratios and Sr contents (310-1020 ppm), strong depletion of HREE (e.g., Yb = 0.80-1.44 ppm) and Y (7.68-14.50 ppm), and all enriched in Rb, Sr, Ba, K and depleted in Nb and Ti. They are characterized by distinctive Eu positive anomalies, high Na2O contents and MORB-like Sr and Nd isotope signatures (high εNd(t) = +6.1 to +7.0 and low (87Sr/86Sr)i = 0.70412-0.70462). These adakites most likely formed by melting of a young/hot subducted oceanic slab, and adakites in general are important carriers of porphyry Cu ± (Au) deposits. Early Carboniferous adakites in the Tuwu area south of Kalatage are known to have similar features. Therefore, skarn-mineralized porphyry adakites get younger from north to south, suggesting southward migration of the Harlik-Dananhu arc from 390 Ma to 322 Ma. These data indicate that partial melting of hot (and/or young) oceanic crustal slabs were an important mechanism of accretionary crustal growth and mineralization in the southern CAOB.

Oncoplastic Surgery for Upper/Upper Inner Quadrant Breast Cancer.

Science.gov (United States)

Lin, Joseph; Chen, Dar-Ren; Wang, Yu-Fen; Lai, Hung-Wen

2016-01-01

Tumors located in the upper/upper inner quadrant of the breast warrant more attention. A small lesion relative to the size of breast in this location may be resolved by performing a level I oncoplastic technique. However, a wide excision may significantly reduce the overall quality of the breast shape by distorting the visible breast line. From June 2012 to April 2015, 36 patients with breast cancer located in the upper/upper inner quadrant underwent breast-conservation surgery with matrix rotation mammoplasty. According to the size and location of the tumor relative to the nipple-areola complex, 11 patients underwent matrix rotation with periareolar de-epithelialization (donut group) and the other 25 underwent matrix rotation only (non-donut group). The cosmetic results were self-assessed by questionnaires. The average weights of the excised breast lumps in the donut and non-donut groups were 104.1 and 84.5 g, respectively. During the 3-year follow-up period, local recurrence was observed in one case and was managed with nipple-sparing mastectomy followed by breast reconstruction with prosthetic implants. In total, 31 patients (88.6%) ranked their postoperative result as either acceptable or satisfactory. The treated breasts were also self-evaluated by 27 patients (77.1%) to be nearly identical to or just slightly different from the untreated side. Matrix rotation is an easy breast-preserving technique for treating breast cancer located in the upper/upper inner quadrant of the breast that requires a relatively wide excision. With this technique, a larger breast tumor could be removed without compromising the breast appearance.

Multiple, novel biologically active endophytic actinomycetes isolated from upper Amazonian rainforests.

Science.gov (United States)

Bascom-Slack, Carol A; Ma, Cong; Moore, Emily; Babbs, Beatrice; Fenn, Kathleen; Greene, Joshua S; Hann, Bradley D; Keehner, Jocelyn; Kelley-Swift, Elizabeth G; Kembaiyan, Vivek; Lee, Sun Jin; Li, Puyao; Light, David Y; Lin, Emily H; Schorn, Michelle A; Vekhter, Daniel; Boulanger, Lori-Ann; Hess, W M; Vargas, Percy Núñez; Strobel, Gary A; Strobel, Scott A

2009-08-01

Microbial biodiversity provides an increasingly important source of medically and industrially useful compounds. We have isolated 14 actinomycete species from a collection of approximately 300 plant stem samples from the upper Amazonian rainforest in Peru. All of the cultured isolates produce substances with inhibitory activity directed at a range of potential fungal and bacterial pathogens. For some organisms, this activity is very broad in spectrum while other organisms show specific activity against a limited number of organisms. Two of these organisms preferentially inhibit bacterial test organisms over eukaryotic organisms. rDNA sequence analysis indicates that these organisms are not equivalent to any other cultured deposits in GenBank. Our results provide evidence of the untapped biodiversity in the form of biologically active microbes present within the tissues of higher plants.

External Environment and Upper Echelons Theory

DEFF Research Database (Denmark)

Escribá-Esteve, Alejandro; Nielsen, Sabina; Yamak, Sibel

This work reviews empirical research on TMTs with a specific emphasis on the role of the external environment. We extend the existing research on upper echelons theory, which has largely focused on the team and firm level of analyses of top management teams (TMT). Considering institutional...... and industrial organization theories, we elaborate a cross-level conceptual model outlining the direct, mediating and moderating effects of the external environment on TMTs and their impact. Our review distinguishes between industry and institutional level of analyses and three types of environmental...

Preliminary vitrinite and bitumen reflectance, total organic carbon, and pyrolysis data for samples from Upper and Lower Cretaceous strata, Maverick Basin, south Texas

Science.gov (United States)

Hackley, Paul C.; Dennen, Kristin O.; Gesserman, Rachel M.; Ridgley, Jennie L.

2009-01-01

The Lower Cretaceous Pearsall Formation, a regionally occurring limestone and shale interval of 500-600-ft maximum thickness (Rose, 1986), is being evaluated as part of an ongoing U.S. Geological Survey (USGS) assessment of undiscovered hydrocarbon resources in onshore Lower Cretaceous strata of the northern Gulf of Mexico. The purpose of this report is to release preliminary vitrinite and bitumen reflectance, total organic carbon, and pyrolysis data for Pearsall Formation, Glen Rose Formation, Hosston Formation, Austin Group, and Eagle Ford Group samples from the Maverick Basin in south Texas in order to aid in the characterization of these strata in this area. The preliminary nature of this report and the data contained herein reflect that the assessment and characterization of these samples is a work currently in progress. Pearsall Formation subdivisions are, in ascending stratigraphic order, the Pine Island Shale, James Limestone, and Bexar Shale Members (Loucks, 2002). The Lower Cretaceous Glen Rose Formation is also part of the USGS Lower Cretaceous assessment and produces oil in the Maverick Basin (Loucks and Kerans, 2003). The Hosston Formation was assessed by the USGS for undiscovered oil and gas resources in 2006 (Dyman and Condon, 2006), but not in south Texas. The Upper Cretaceous Austin Group is being assessed as part of the USGS assessment of undiscovered hydrocarbon resources in the Upper Cretaceous strata of the northern Gulf of Mexico and, along with the Upper Cretaceous Eagle Ford Group, is considered to be an important source rock in the Smackover-Austin-Eagleford Total Petroleum System (Condon and Dyman, 2006). Both the Austin Group and the Eagle Ford Group are present in the Maverick Basin in south Texas (Rose, 1986).

Geochemical characterization and miospore biochronostratigraphy of the Frasnian anoxic event in the Parnaiba basin, Northeast Brazil

International Nuclear Information System (INIS)

Rodrigues, R.; De Melo, J.H.G.; Alves, D.B.; Loboziak, S.

1995-01-01

Radioactive shales of Frasnian age in the Parnaiba Basin present high concentrations of organic matter. They correspond to a condensed section related to the Devonian maximum marine transgression. Combined geochemical, palynological and clay mineral data point out to a dominant algal contribution in the composition of the organic matter, as well as to anoxic depositional settings. This radioactive shale interval corresponds to the onset of a long-lasting, global anoxic event which was to be intensified in the Late Frasnian, and thus can be regarded as a marker for chronostratigraphic correlations. It includes the main source rocks of Devonian age in the Palaeozoic basins of north Brazil, and therefore represents a target of potential interest for hydrocarbon exploration. (authors). 16 refs., 10 figs., 1 tab., 17 photos

Geochemical characterization and miospore biochronostratigraphy of the Frasnian anoxic event in the Parnaiba basin, Northeast Brazil

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, R.; De Melo, J.H.G.; Alves, D.B. [Universidade Federal, Rio de Janeiro, RJ (Brazil); Loboziak, S. [Lille-1 Univ., 59 - Villeneuve-d`Ascq (France)

1995-12-31

Radioactive shales of Frasnian age in the Parnaiba Basin present high concentrations of organic matter. They correspond to a condensed section related to the Devonian maximum marine transgression. Combined geochemical, palynological and clay mineral data point out to a dominant algal contribution in the composition of the organic matter, as well as to anoxic depositional settings. This radioactive shale interval corresponds to the onset of a long-lasting, global anoxic event which was to be intensified in the Late Frasnian, and thus can be regarded as a marker for chronostratigraphic correlations. It includes the main source rocks of Devonian age in the Palaeozoic basins of north Brazil, and therefore represents a target of potential interest for hydrocarbon exploration. (authors). 16 refs., 10 figs., 1 tab., 17 photos.

[The response of the upper respiratory tract to the impact of atmospheric pollution].

Science.gov (United States)

Mukhamadiev, R A; Ismagilov, Sh M

2015-01-01

The present literature review characterizes the environmental conditions in the Russian Federation in general and the Republic of Tatarstan in particular with special reference to the influence of atmospheric pollution on the development and the clinical picture of the diseases of the respiratory organs including pathology of the upper respiratory tract in the populations of the industrial centres and other environmentally unfriendly areas. The views of the domestic and foreign authors concerning the role of the environmental factors in the clinical picture of the upper respiratory tract disorders are described in detail. The authors emphasize the necessity of the further investigationsinto this problem and the development of the methods for the prevention of diseases of the upper respiratory react.

Depositional environments and sequence stratigraphy of the Bahram Formation (middle–late Devonian in north of Kerman, south-central Iran

Directory of Open Access Journals (Sweden)

Afshin Hashmie

2016-09-01

Full Text Available This study is focused on sedimentary environments, facies distribution, and sequence stratigraphy. The facies and sequence stratigraphic analyses of the Bahram Formation (middle–late Devonian in south-central Iran are based on two measured stratigraphic sections in the southern Tabas block. The Bahram Formation overlies red sandstones Padeha Formation in sections Hutk and Sardar and is overlain by Carboniferous carbonate deposits of Hutk Formation paraconformably, with a thickness of 354 and 386 m respectively. Mixed siliciclastic and carbonate sediments are present in this succession. The field observations and laboratory studies were used to identify 14 micro/petrofacies, which can be grouped into 5 depositional environments: shore, tidal flat, lagoon, shoal and shallow open marine. A mixed carbonate-detrital shallow shelf is suggested for the depositional environment of the Bahram Formation which deepens to the east (Sardar section and thins in southern locations (Hutk section. Three 3rd-order cyclic siliciclastic and carbonate sequences in the Bahram Formation and one sequence shared with the overlying joint with Hutk Formation are identified, on the basis of shallowing upward patterns in the micro/pertofacies.

Oncoplastic Surgery for Upper/Upper Inner Quadrant Breast Cancer.

Directory of Open Access Journals (Sweden)

Joseph Lin

Full Text Available Tumors located in the upper/upper inner quadrant of the breast warrant more attention. A small lesion relative to the size of breast in this location may be resolved by performing a level I oncoplastic technique. However, a wide excision may significantly reduce the overall quality of the breast shape by distorting the visible breast line. From June 2012 to April 2015, 36 patients with breast cancer located in the upper/upper inner quadrant underwent breast-conservation surgery with matrix rotation mammoplasty. According to the size and location of the tumor relative to the nipple-areola complex, 11 patients underwent matrix rotation with periareolar de-epithelialization (donut group and the other 25 underwent matrix rotation only (non-donut group. The cosmetic results were self-assessed by questionnaires. The average weights of the excised breast lumps in the donut and non-donut groups were 104.1 and 84.5 g, respectively. During the 3-year follow-up period, local recurrence was observed in one case and was managed with nipple-sparing mastectomy followed by breast reconstruction with prosthetic implants. In total, 31 patients (88.6% ranked their postoperative result as either acceptable or satisfactory. The treated breasts were also self-evaluated by 27 patients (77.1% to be nearly identical to or just slightly different from the untreated side. Matrix rotation is an easy breast-preserving technique for treating breast cancer located in the upper/upper inner quadrant of the breast that requires a relatively wide excision. With this technique, a larger breast tumor could be removed without compromising the breast appearance.

Nonvariceal upper gastrointestinal bleeding

International Nuclear Information System (INIS)

Burke, Stephen J.; Weldon, Derik; Sun, Shiliang; Golzarian, Jafar

2007-01-01

Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

Nonvariceal upper gastrointestinal bleeding

Energy Technology Data Exchange (ETDEWEB)

Burke, Stephen J.; Weldon, Derik; Sun, Shiliang [University of Iowa, Department of Radiology, Iowa, IA (United States); Golzarian, Jafar [University of Iowa, Department of Radiology, Iowa, IA (United States); University of Iowa, Department of Radiology, Carver College of Medicine, Iowa, IA (United States)

2007-07-15

Nonvariceal upper gastrointestinal bleeding (NUGB) remains a major medical problem even after advances in medical therapy with gastric acid suppression and cyclooxygenase (COX-2) inhibitors. Although the incidence of upper gastrointestinal bleeding presenting to the emergency room has slightly decreased, similar decreases in overall mortality and rebleeding rate have not been experienced over the last few decades. Many causes of upper gastrointestinal bleeding have been identified and will be reviewed. Endoscopic, radiographic and angiographic modalities continue to form the basis of the diagnosis of upper gastrointestinal bleeding with new research in the field of CT angiography to diagnose gastrointestinal bleeding. Endoscopic and angiographic treatment modalities will be highlighted, emphasizing a multi-modality treatment plan for upper gastrointestinal bleeding. (orig.)

Upper Gastrointestinal (GI) Series

Science.gov (United States)

... standard barium upper GI series, which uses only barium a double-contrast upper GI series, which uses both air and ... evenly coat your upper GI tract with the barium. If you are having a double-contrast study, you will swallow gas-forming crystals that ...

Minimal differences in prevalence and spectrum of organic disease at upper gastrointestinal endoscopy between selected secondary care patients with symptoms of gastro-oesophageal reflux or dyspepsia.

Science.gov (United States)

Irvine, Andrew J; Pinto-Sanchez, Maria Ines; Bercik, Premysl; Moayyedi, Paul; Ford, Alexander C

2017-04-01

Gastro-oesophageal reflux and dyspepsia are felt to be separate upper gastrointestinal (GI) conditions. We aimed to measure the degree of overlap between them, and assess whether endoscopic findings differed. Demographic, symptom, upper GI endoscopy and histology data were collected from consecutive adults in secondary care. Patients were categorised according to whether they reported gastro-oesophageal reflux alone, dyspepsia alone or both, and patient demographics and endoscopic findings were compared. Of 1167 patients, 97 (8.3%) had gastro-oesophageal reflux alone, 571 (48.9%) dyspepsia alone, and 499 (42.8%) overlap. Patients with overlap symptoms were more likely to smoke, compared with those with gastro-oesophageal reflux alone, or dyspepsia alone (p = .009), but there were no other differences. Patients with gastro-oesophageal reflux alone or overlap had a higher prevalence of erosive oesophagitis (18.6% and 15.4% respectively, p Gastro-oesophageal reflux and dyspepsia symptoms commonly overlap. There were minimal differences in demographics or spectrum of underlying organic disease between various symptom groups, suggesting that restrictive classifications according to predominant symptom may not be clinically useful.

Parental Sources of High-Alumina Alkaline Melts: Nd, Sr, Pb, and O Isotopic Evidence from the Devonian Kiya-Shaltyr Gabbro-Urtite Intrusion, South Siberia

Science.gov (United States)

Vrublevskii, V. V.; Gertner, I. F.; Chugaev, A. V.

2018-04-01

The isotope geochemistry (ɛNd( t) 4.8-5.4, 206Pb/204Pb in 18.05-18.36, 207Pb/204Pbin 15.53-15.57, 208Pb/204Pb in 37.59-37.83, 87Sr/86Sr( t) 0.7048-0.7057, δ18OSMOW 8-10.5‰) and trace element composition of the Kiya-Shaltyr gabbro-urtite pluton allow us to suggest a heterogeneous source and complex geodynamic settings of the Devonian alkali magmatism in the Kuznetsk Alatau. It is assumed that its evolution took place under conditions of partial mingling of matter of the depleted (PREMA) and enriched (EM) mantle with crustal contamination of the evolving melt. Such an interaction could have been a result of superposition of a mantle plume and an active margin (OIB and IAB components). In fold belts this led to the formation of hybrid high-alumina foidoite magmas.

Organic richness and organic matter quality studies of source rocks ...

African Journals Online (AJOL)

The hydrocarbon potential of the Upper Cretaceous units (Maastrichtian Mamu Formation) exposed at Imiegba and environs of the Benin Flank, Western Anambra Basin was assessed by Total Organic Carbon (TOC) and Rock-Eval Pyrolysis Analyses. The investigated sections of the Mamu Formation consist of dark grey to ...

Seven 365-Million-Year-Old Trilobites Moulting within a Nautiloid Conch

OpenAIRE

Zong, Rui-Wen; Fan, Ruo-Ying; Gong, Yi-Ming

2016-01-01

A nautiloid conch containing many disarticulated exoskeletons of Omegops cornelius (Phacopidae, Trilobita) was found in the Upper Devonian Hongguleleng Formation of the northwestern margin of the Junggar Basin, NW China. The similar number of cephala, thoraces and pygidia, unbroken thoraces, explicit exuviae, and lack of other macrofossils in the conch, indicate that at least seven individual trilobites had moulted within the nautiloid living chamber, using the vacant chamber of a dead nautil...

Radiology trainer. Torso, internal organs and vessels. 2. ed.; Radiologie-Trainer. Koerperstamm, innere Organe und Gefaesse

Energy Technology Data Exchange (ETDEWEB)

Staebler, Axel [Orthopaedische Klinik Harlaching, Muenchen (Germany). Radiologische Praxis; Erlt-Wagner, Birgit (eds.) [Klinikum der Universitaet Muenchen (Germany). Inst. fuer Klinische Radiologie

2013-11-01

The radiology training textbook is based on case studies of the clinical experience, including radiological imaging and differential diagnostic discussion. The scope of this volume covers the torso, internal organs and vessels. The following issues are discussed: lungs, pleura, mediastinum; heart and vascular system; upper abdomen organs; gastrointestinal tract; urogenital system.

Quantifying opening-mode fracture spatial organization in horizontal wellbore image logs, core and outcrop: Application to Upper Cretaceous Frontier Formation tight gas sandstones, USA

Science.gov (United States)

Li, J. Z.; Laubach, S. E.; Gale, J. F. W.; Marrett, R. A.

2018-03-01

The Upper Cretaceous Frontier Formation is a naturally fractured gas-producing sandstone in Wyoming. Regionally, random and statistically more clustered than random patterns exist in the same upper to lower shoreface depositional facies. East-west- and north-south-striking regional fractures sampled using image logs and cores from three horizontal wells exhibit clustered patterns, whereas data collected from east-west-striking fractures in outcrop have patterns that are indistinguishable from random. Image log data analyzed with the correlation count method shows clusters ∼35 m wide and spaced ∼50 to 90 m apart as well as clusters up to 12 m wide with periodic inter-cluster spacings. A hierarchy of cluster sizes exists; organization within clusters is likely fractal. These rocks have markedly different structural and burial histories, so regional differences in degree of clustering are unsurprising. Clustered patterns correspond to fractures having core quartz deposition contemporaneous with fracture opening, circumstances that some models suggest might affect spacing patterns by interfering with fracture growth. Our results show that quantifying and identifying patterns as statistically more or less clustered than random delineates differences in fracture patterns that are not otherwise apparent but that may influence gas and water production, and therefore may be economically important.

Origin of natural waters and gases within the Upper Carboniferous coal-bearing and autochthonous Miocene strata in South-Western part of the Upper Silesian Coal Basin, Poland

International Nuclear Information System (INIS)

Kotarba, Maciej J.; Pluta, Irena

2009-01-01

The molecular and stable isotope compositions of coalbed gases from the Upper Carboniferous strata and natural gases accumulated within the autochthonous Upper Miocene Skawina Formation of the Debowiec-Simoradz gas deposit were determined, as well as the chemical and stable isotope compositions of waters from the Skawina Formation and waters at the top of the Upper Carboniferous strata of the Kaczyce Ridge (the abandoned 'Morcinek' coal mine) in the South-Western part of the Upper Silesian Coal Basin. Two genetic types of natural gases within the Upper Carboniferous coal-bearing strata were identified: thermogenic (CH 4 , small amounts of higher gaseous hydrocarbons, and CO 2 ) and microbial (CH 4 , very small amounts of ethane, and CO 2 ). Thermogenic gases were generated during the bituminous stage of coalification and completed at the end of the Variscan orogeny. Degassing (desorption) of thermogenic gases began at the end of late Carboniferous until the late Miocene time-period and extended to the present-day. This process took place in the Upper Carboniferous strata up to a depth of about 550 m under the sealing Upper Miocene cover. A primary accumulation zone of indigenous, thermogenic gases is present below the degassing zone. Up to 200 m depth from the top of the Upper Carboniferous strata, within the weathered complex, an accumulation zone of secondary, microbial gas occurs. Waters within these strata are mainly of meteoric origin of the infiltration period just before the last sea transgression in the late Miocene and partly of marine origin having migrated from the Upper Miocene strata. Then, both methanogenic archaebacteria and their nutrients were transported by meteoric water into the near-surface Carboniferous strata where the generated microbial CH 4 saturated coal seams. Waters within the Miocene strata of the Debowiec-Simoradz and Zablocie are of marine origin, and natural gases accumulated within autochthonous Miocene strata of the Debowiec

New morphological information on, and species of placoderm fish Africanaspis (Arthrodira, Placodermi from the Late Devonian of South Africa.

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Robert W Gess

Full Text Available Here we present a new species of placoderm fish, Africanaspis edmountaini sp. nov., and redescribe Africanaspis doryssa on the basis of new material collected from the type locality of Africanaspis. The new material includes the first head shields of Africanaspis doryssa in addition to soft anatomy for both taxa. Hitherto Africanaspis was entirely described from trunk armour and no record of body and fin outlines had been recorded. In addition the first record of embryonic and juvenile specimens of Africanaspis doryssa is presented and provides a growth series from presumed hatchlings to presumed adults. The presence of a greater number of juveniles compared to adults indicates that the Waterloo Farm fossil site in South Africa represents the first nursery site of arthrodire placoderms known from a cold water environment. The preservation of an ontogenetic series demonstrates that variation within the earlier known sample, initially considered to have resulted from ontogenetic change, instead indicates the presence of a second, less common species Africanaspis edmountaini sp. nov. There is some faunal overlap between the Waterloo Farm fossil site and faunas described from Strud in Belgium and Red Hill, Pennsylvania, in north America, supporting the concept of a more cosmopolitan vertebrate fauna in the Famennian than earlier in the Devonian.

New morphological information on, and species of placoderm fish Africanaspis (Arthrodira, Placodermi) from the Late Devonian of South Africa

Science.gov (United States)

2017-01-01

Here we present a new species of placoderm fish, Africanaspis edmountaini sp. nov., and redescribe Africanaspis doryssa on the basis of new material collected from the type locality of Africanaspis. The new material includes the first head shields of Africanaspis doryssa in addition to soft anatomy for both taxa. Hitherto Africanaspis was entirely described from trunk armour and no record of body and fin outlines had been recorded. In addition the first record of embryonic and juvenile specimens of Africanaspis doryssa is presented and provides a growth series from presumed hatchlings to presumed adults. The presence of a greater number of juveniles compared to adults indicates that the Waterloo Farm fossil site in South Africa represents the first nursery site of arthrodire placoderms known from a cold water environment. The preservation of an ontogenetic series demonstrates that variation within the earlier known sample, initially considered to have resulted from ontogenetic change, instead indicates the presence of a second, less common species Africanaspis edmountaini sp. nov. There is some faunal overlap between the Waterloo Farm fossil site and faunas described from Strud in Belgium and Red Hill, Pennsylvania, in north America, supporting the concept of a more cosmopolitan vertebrate fauna in the Famennian than earlier in the Devonian. PMID:28379973

Factors controlling Li concentration and isotopic composition in formation waters and host rocks of Marcellus Shale, Appalachian Basin

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Phan, Thai T.; Capo, Rosemary C; Stewart, Brian W.; Macpherson, Gwen; Rowan, Elisabeth L.; Hammack, Richard W.

2015-01-01

In this study, water and whole rock samples from hydraulically fractured wells in the Marcellus Shale (Middle Devonian), and water from conventional wells producing from Upper Devonian sandstones were analyzed for lithium concentrations and isotope ratios (δ7Li). The distribution of lithium concentrations in different mineral groups was determined using sequential extraction. Structurally bound Li, predominantly in clays, accounted for 75-91 wt. % of total Li, whereas exchangeable sites and carbonate cement contain negligible Li (shale in Greene Co., Pennsylvania, and Tioga Co., New York, ranged from -2.3 to + 4.3‰, similar to values reported for other shales in the literature. The δ7Li values in shale rocks with stratigraphic depth record progressive weathering of the source region; the most weathered and clay-rich strata with isotopically light Li are found closest to the top of the stratigraphic section. Diagenetic illite-smectite transition could also have partially affected the bulk Li content and isotope ratios of the Marcellus Shale.

Hydrology, water quality, and effects of drought in Monroe County, Michigan

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Nicholas, J.R.; Rowe, Gary L.; Brannen, J.R.

1996-01-01

streamwater at low flow is suitable for most domestic u~es, irrigation, and recreation. In ground water, dissolved solids and hydrogen sulfide are present at concentrations objectionable to some users. Indicators of ground-water contamination from agricultural activities-pesticides and nitrates-were not present at detectable concentrations or were below U.S. Environmental Protection Agency (USEPA) limits. In streamwater, some treatment to remove bacteria may be necessary in summer months; nitrate concentrations, however, were found to be below USEPA limits.Tritium concentrations indicative of recent recharge to the Silurian-Devonian aquifer are present in a southwest-to-northeast-trending band from Whiteford to Berlin Townships. Generally, where glacial deposits are thicker than 30 feet, rech~rge.takes more than 40 years. Carbon isotope data md1cate that some of the ground water in the Silurian-Devonian aquifer is more than 14,000 years old.Mild droughts are common in Michigan, but long severe droughts, such as those during 1930-37 and 1960-67, are infrequent. The most recent drought, during 1988, was severe but short. Ground-water levels declined throughout the county; the largest declines were probably in the southwest. Shallow bedrock wells completed in only the upper part of the Silurian-Devonian aquifer and near large uses of ground water were especially susceptible to the effects of drought. Deep bedrock wells continued to produce water through the drought of 1988.During droughts, streamflow is reduced because of low ground-water levels and high consumptive uses of surface water. In 1988, annual discharge on the River Raisin was near normal, but monthly averages were below normal from March through August. The quality of surface water during droughts is similar to that during normal lowflow conditions.

Geochemical and strontium isotope characterization of produced waters from Marcellus Shale natural gas extraction.

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Chapman, Elizabeth C; Capo, Rosemary C; Stewart, Brian W; Kirby, Carl S; Hammack, Richard W; Schroeder, Karl T; Edenborn, Harry M

2012-03-20

Extraction of natural gas by hydraulic fracturing of the Middle Devonian Marcellus Shale, a major gas-bearing unit in the Appalachian Basin, results in significant quantities of produced water containing high total dissolved solids (TDS). We carried out a strontium (Sr) isotope investigation to determine the utility of Sr isotopes in identifying and quantifying the interaction of Marcellus Formation produced waters with other waters in the Appalachian Basin in the event of an accidental release, and to provide information about the source of the dissolved solids. Strontium isotopic ratios of Marcellus produced waters collected over a geographic range of ~375 km from southwestern to northeastern Pennsylvania define a relatively narrow set of values (ε(Sr)(SW) = +13.8 to +41.6, where ε(Sr) (SW) is the deviation of the (87)Sr/(86)Sr ratio from that of seawater in parts per 10(4)); this isotopic range falls above that of Middle Devonian seawater, and is distinct from most western Pennsylvania acid mine drainage and Upper Devonian Venango Group oil and gas brines. The uniformity of the isotope ratios suggests a basin-wide source of dissolved solids with a component that is more radiogenic than seawater. Mixing models indicate that Sr isotope ratios can be used to sensitively differentiate between Marcellus Formation produced water and other potential sources of TDS into ground or surface waters.

Volume rejuvenation of the facial upper third.

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Buckingham, Edward D; Glasgold, Robert; Kontis, Theda; Smith, Stephen P; Dolev, Yalon; Fitzgerald, Rebecca; Lam, Samuel M; Williams, Edwin F; Pollei, Taylor R

2015-02-01

The next three articles in this issue take a unique approach to discussing volumetric restoration. Robert Glasgold has provided an assessment for each facial region and five different renowned authors (TK, SPS, RF, SML, and EFW) have been asked to speak on a particular volumetric product, of which they are considered an expert, as it applies to the different regions of the face. The articles are broken into the following: (1) upper third which corresponds to the upper eyelid, brow, temple, and forehead; (2) middle third which will cover lower eyelid, cheek, and perioral area; and (3) lower third which discusses the marionette, prejowl, and jawline. Our hope is that by placing differing opinions of experienced authors, organized by facial region together, the reader will have the opportunity to more readily compare the options. The contributing authors and their product area are as follows: Theda Kontis, MD-hyaluronic acid; Steve Smith, MD-calcium hydroxyl appetite; Rebecca Fitzgerald, MD-poly-L lactic acid; Sam Lam, MD-polymethyl methacrylate; and Edwin Williams, MD-Autologous Fat Transfer. If the author included general comments on the product, they are included in the article on the upper face only and are not repeated. Please note that other individuals may also have significantly assisted in the production of these articles, but those listed above are the senior authors. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Poster 6: Influence of traces elements in the organic chemistry of upper atmosphere of Titan

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Mathe, Christophe; Carrasco, Nathalie; Trainer, Melissa G.; Gautier, Thomas; Gavilan, Lisseth; Dubois, David; Li, Xiang

2016-06-01

In the upper atmosphere of Titan, complex chemistry leads to the formation of organic aerosols. Since the work of Khare et al. in 1984, several experiments investigated the formation of Titan aerosols, so called tholins, in the laboratory. It has been suggested that nitrogen-containing compounds may contribute significantly to the aerosols formation process. In this study, we focused on the influence of pyridine, the simplest nitrogenous aromatic hydrocarbon, on the chemistry of Titan's atmosphere and on aerosol formation. To assess the effect of pyridine on aerosol formation chemistry, we used two different experimental setups : a capacitively coupled radio-frequency (electronic impact), and a VUV Deuterium lamp (photochemistry) in a collaboration between LATMOS (Guyancourt) and NASA-GSFC (Greenbelt), respectively. Aerosols produced with both setups were first analyzed using a FTIR-ATR (Fourier Transform Infrared spectroscopy - Attenuated Total Reflection) with a spectral range of 4000-800 cm-1 to characterize their optical properties. Next the samples were analysed using a Bruker Autoflex Speed MALDI mass spectrometer with a m/z range up to 2000 Da in order to infer their composition. Infrared spectroscopy analysis showed that tholins produced with a nitrogen-methane gas mixture (95:5) and nitrogenpyridine gas mixture (99:250ppm) present very similar spectra features. Tholins produced with a mixture of nitrogenmethane-pyridine (99:1:250ppm) do not present aliphatic CH2 or CH3 vibrational signatures. This could indicate a cyclic polymerization by a pyridine skeleton. Mass spectrometry is still in progress to confirm this.

Computer vision for shoe upper profile measurement via upper and sole conformal matching

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Hu, Zhongxu; Bicker, Robert; Taylor, Paul; Marshall, Chris

2007-01-01

This paper describes a structured light computer vision system applied to the measurement of the 3D profile of shoe uppers. The trajectory obtained is used to guide an industrial robot for automatic edge roughing around the contour of the shoe upper so that the bonding strength can be improved. Due to the specific contour and unevenness of the shoe upper, even if the 3D profile is obtained using computer vision, it is still difficult to reliably define the roughing path around the shape. However, the shape of the corresponding shoe sole is better defined, and it is much easier to measure the edge using computer vision. Therefore, a feasible strategy is to measure both the upper and sole profiles, and then align and fit the sole contour to the upper, in order to obtain the best fit. The trajectory of the edge of the desired roughing path is calculated and is then smoothed and interpolated using NURBS curves to guide an industrial robot for shoe upper surface removal; experiments show robust and consistent results. An outline description of the structured light vision system is given here, along with the calibration techniques used.

Upper GI Bleeding in Children

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Upper GI Bleeding in Children What is upper GI Bleeding? Irritation and ulcers of the lining of the esophagus, stomach or duodenum can result in upper GI bleeding. When this occurs the child may vomit blood ...

Origin of uranium and other metal concentrations in the Helmsdate granite and the Devonian sediments of the north-east of Scotland

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Tweedie, J R

1981-01-01

An examination of the radiometrically anomalous Caledonian Helmsdale granite and certain radiometric localities in the Devonian sediments of Caithness has been undertaken in order to discover the processes of U concentration in the different rock types. The study is based mainly on geochemical examination, with analyses for U, Th, Cu, Zn, Pb, Mo, Zr, Rb, Sr, Bi, Se, P/sub 2/O/sub 5/, and K/sub 2/O being carried out. The granite was found to have a high mean U content (9 ppm), approximately twice that expected from comparison with the world granite average (4 ppm), whilst zones of intense alteration gave U enrichments of up to 71 ppm. These latter have a mineralogy and geochemistry distinct from the normal granite. A limited Cu-Mo stockwork mineralisation was discovered almost coincident with a highly radioactive hydrocarbon vein. The main U concentrations in the Caithness sediments occur in thin phosphatic horizons. In these, U ranges from 100 to 1000 ppm and is paralleled by the phosphate in an approximately linear relationship of 100 ppm U/1% P/sub 2/O/sub 5/. Black shales contain low level U concentrations with anomalously high Zn and/or Mo. (author).

Geochemistry and Cyclostratigraphy of Magnetic Susceptibility data from the Frasnian-Famennian event interval in western Canada: Insights in the pattern and timing of a biotic crisis

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Whalen, M. T.; De Vleeschouwer, D.; Sliwinski, M. G.; Claeys, P. F.; Day, J. E.

2012-12-01

Cyclostratigraphic calibration of magnetic susceptibility data along with stable isotopic and geochemical proxy data for redox, productivity, and detrital input from western Canada provide insight into the pace and timing of the Late Devonian, Frasnian-Famennian (F-F) biotic crisis. Two organic-rich shales that, in much of the world, display geochemical anomalies indicating low oxygen conditions and carbon burial characterize the F-F event. These events, referred to as the Lower and Upper Kellwasser events (LKE & UKE), have been linked to the evolutionary expansion of deeply rooted terrestrial forests and the concomitant changes in soil development and chemical weathering and changes in Late Devonian climate. Our geochemical data record relatively high levels of redox sensitive trace metals (Mo, U, V), proxies for biological productivity (Ba, Cu, Ni, Zn), and detrital input (Al, Si, Ti, Zr) during both events. C stable isotopic data generated from organic matter records a 3-4‰ positive excursion during both events. Each event is recorded in lowstand and/or early transgressive facies. These data corroborate hypotheses about enhanced biological productivity, driven by heightened terrestrial detrital input, leading to low oxygen conditions and decreases in biotic diversity during during relatively low stands of Late Devonian sea level. Age dating of such events in deep time is problematic due to insufficient biochronologic control. Each event is within one conodont biostratigraphic zone, with durations on the order of 0.5-1.0 Ma. Time series analysis of high-resolution magnetic susceptibility data identified 16 long eccentricity cycles (405 ky) during the Frasnian stage and one in the earliest Famennian stage. The geochemical anomalies associated with the LKE and UKE are recorded over 7 and 14 m of stratigraphic section respectively. These strata represent only a portion of a 405 ky long eccentricity cycle and astronomical tuning implies that the LKE likely occurred

QUALITY WATER BALANCE AS A BASE FOR WETLANDS RESTORATION IN THE UPPER BIEBRZA VALLEY

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Piotr Banaszuk

2016-06-01

Full Text Available Main goal of presented research was the assessment of the influence of water damming in existing land reclamation systems on the surface water quality of the Upper Biebrza River catchment. Surface water quality was assessed on the concentration of BOD5, total phosphorus (TP and total nitrogen (TN recorded in 2014 at several monitoring points along Biebrza River and its tributaries. The upper Biebrza R. has a little (at the Sztabin gauging point even an insufficient absorption capacity of organic pollutants and a high capacity for self-purifying and absorbing of TP and TN. The phosphorus binding capacity decreases along the river and in its upper reach it is necessary to reduce the load of P by 20% to maintain the river quality objectives. Water quality monitoring data and information about pollution sources showed high absorption capacities of TN in the monitored tributaries, which can receive an additional flux of this constituent in the amount exceeding the actual load up to several times. The absorption capacity of BOD5 and TP is lower by an order of magnitude. For Kropiwna R., it is required to reduce the load of organic components (measured as BOD5, which exceeds the requirements for the 1st quality class.

A Proposition Of Knowledge Management Methodology For The Purpose Of Reasoning With The Use Of An Upper-Ontology

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Kamil Szymański

2007-01-01

Full Text Available This article describes a proposition of knowledge organization for the purpose of reasoningusing an upper-ontology. It presents a model of integrated ontologies architecture whichconsists of a domain ontologies layer with instances, a shared upper-ontology layer withadditional rules and a layer of ontologies mapping concrete domain ontologies with the upperontology.Thanks to the upper-ontology, new facts were concluded from domain ontologiesduring the reasoning process. A practical realization proposition is given as well. It is basedon some popular SemanticWeb technologies and tools, such as OWL, SWRL, nRQL, Prot´eg´eand Racer.

Teacher Learning within a Multinational Project in an Upper Secondary School

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Liisa Ilomäki

2017-01-01

Full Text Available In this case study, we investigated teachers’ professional learning within a multinational project in an upper secondary school. The aim of the study was to investigate how the participating teachers adopted and applied the trialogical approach (TLA in their pedagogical practices and their challenges in doing that. The mixed method approach was used for data collection and analysis. About one-fourth of the teachers participated in the activities, ten females and three males. Three groups were identified, based on their activity in the project: pilot teachers, active adopters, and adopters. Altogether 79 students (38 males and 41 females answered a questionnaire concerning the pedagogical practices. The pedagogical revisions were well in line with TLA; the revised courses as well as new iterations and new ideas were indicators of the teachers’ creative implementation processes. However, some of the TLA ideas were more difficult to apply in an upper secondary school context; for example, the implementation of ideas involving cross-fertilization with other organizations and cultures was rare. In order to learn new pedagogical practices, teachers need organized time for collaborative planning, for reflecting, and for sharing.

Principals' Leadership in Mexican Upper High Schools: The Paradoxes between Rules and Practices

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Santizo Rodall, Claudia A.; Ortega Salazar, Sylvia B.

2018-01-01

This article discusses the type of organization and leadership that underlies a competency-based management rule established in Mexico (2008) applicable to principals in public upper high schools. This rule, identified as the 449 Agreement, describes competencies and communicates expected behavior. Implementation, however, is mediated by the…

Endoscopic evaluation of upper abdominal symptoms in adult patients, Saudi Aramco-Ai Hasa Health Center, Saudi Arabia.

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Nkrumah, K N

2002-01-01

Upper oesophago-gastro-duodenoscopies (UGI endoscopies) were performed on adult patients who attended Saudi Aramco Health Centre at Al Hasa, Saudi Arabia, between June 1986 and December 1993, with complaint of upper abdominal pain. During this period, three hundred and fifteen (315) patients were examined. Sixty one percent were females and the rest males. Peptic ulcer disease including gastritis was the most common diagnosis made. Helicobacter pylori-like organisms were documented historically in biopsy samples in 113 of 178 (63%) patients. Nearly all were associated with gastritis; no organisms were reported in normal histology specimens. This confirms the association of this organism with gastritis. Gastric cancer suspected radiologically were not confirmed endoscopically or histologically. It is important to endoscope and biopsy for histology suspected gastric cancer and ulcer; a negative result may save the patient from unnecessary surgery, ideally all normal looking gastric mucosa should be biopsied so that histological gastritis is not missed.

Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation.

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Resnik, Linda; Meucci, Marissa R; Lieberman-Klinger, Shana; Fantini, Christopher; Kelty, Debra L; Disla, Roxanne; Sasson, Nicole

2012-04-01

The number of catastrophic injuries caused by improvised explosive devices in the Afghanistan and Iraq Wars has increased public, legislative, and research attention to upper limb amputation. The Department of Veterans Affairs (VA) has partnered with the Defense Advanced Research Projects Agency and DEKA Integrated Solutions to optimize the function of an advanced prosthetic arm system that will enable greater independence and function. In this special communication, we examine current practices in prosthetic rehabilitation including trends in adoption and use of prosthetic devices, financial considerations, and the role of rehabilitation team members in light of our experiences with a prototype advanced upper limb prosthesis during a VA study to optimize the device. We discuss key challenges in the adoption of advanced prosthetic technology and make recommendations for service provision and use of advanced upper limb prosthetics. Rates of prosthetic rejection are high among upper limb amputees. However, these rates may be reduced with sufficient training by a highly specialized, multidisciplinary team of clinicians, and a focus on patient education and empowerment throughout the rehabilitation process. There are significant challenges emerging that are unique to implementing the use of advanced upper limb prosthetic technology, and a lack of evidence to establish clinical guidelines regarding prosthetic prescription and treatment. Finally, we make recommendations for future research to aid in the identification of best practices and development of policy decisions regarding insurance coverage of prosthetic rehabilitation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Upper gastrointestinal bleeding.

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Feinman, Marcie; Haut, Elliott R

2014-02-01

Upper gastrointestinal (GI) bleeding remains a commonly encountered diagnosis for acute care surgeons. Initial stabilization and resuscitation of patients is imperative. Stable patients can have initiation of medical therapy and localization of the bleeding, whereas persistently unstable patients require emergent endoscopic or operative intervention. Minimally invasive techniques have surpassed surgery as the treatment of choice for most upper GI bleeding. Copyright © 2014 Elsevier Inc. All rights reserved.

A new assessment of the Late Devonian antiarchan fish Bothriolepis leptocheira from South Timan (Russia and the biotic crisis near the Frasnian–Famennian boundary

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Ervīns Lukševičs

2017-03-01

Full Text Available The species of the Late Devonian, earliest Famennian placoderm fish Bothriolepis jeremejevi has been downranked to subspecies Bothriolepis leptocheira jeremejevi comb. nov. in a result of detailed morphological studies of the type specimens and abundant new material from the type locality of the Sosnogorsk Formation, South Timan, Komi Republic, Russia. This taxon closely resembles Bothriolepis leptocheira leptocheira from Scotland, B. leptocheira curonica from Latvia, and B. leptocheira ssp. from Severnaya Zemlya differing only in small deviations of the size, proportions and shape of some plates of the armour. The composition of vertebrate assemblages from Scotland, Latvia, and Severnaya Zemlya containing B. leptocheira demonstrates a reduced diversity of antiarch placoderm, acanthodian, and sarcopterygian fishes; however, the Sosnogorsk assemblage differs in a larger diversity containing very primitive tetrapod and diversified sarcopterygian fishes including dipnoans and porolepiforms but lacking acanthodians. Wide distribution of a single species of Bothriolepis and usually diminished diversity of vertebrates suggest that the earliest Famennian vertebrate assemblages conform the survival faunas of the latest Frasnian–earliest Famennian biotic crisis.

Ichnological record of the Frasnian-Famennian boundary interval: two examples from the Holy Cross Mts (Central Poland)

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Stachacz, Michał; Uchman, Alfred; Rodríguez-Tovar, Francisco J.

2017-01-01

The Frasnian-Famennian (Late Devonian) boundary interval within the carbonate-siliciclastic series in the Kowala and Płucki sections (Holy Cross Mts, Central Poland) has been analysed to evaluate the influence of the Kellwasser event on the macrobenthic tracemaker community. The Upper Kellwasser event has a lithologically variable record, as horizons of flints (Kowala) and as a bed of bituminous, black, cephalopod limestone (Płucki). Both sections show mostly laminated, unbioturbated beds of marlstones or shales just above the Frasnian-Famennian boundary, which point to events of anoxia on the sea floor. However, the first anoxic horizon occurs below the Frasnian-Famennian boundary. The trace fossils and bioturbational structures are uncommon and poorly diversified. Trichichnus and Multina are the only frequent trace fossils in some beds. Moreover, one horizon above the Frasnian-Famennian boundary contains numerous Multina and a single ? Planolites. Such poorly diversified trace fossil assemblage suggests an unfavourable environment for most of burrowing organisms and fluctuations in oxygenation from anoxic, to dysoxic conditions. The occurrence of the trace fossils and bioturbational structures as spotted and mottled ichnofabrics from the 1.3 m above the Frasnian-Famennian boundary is interpreted as an improvement in bottom water oxygen conditions after the Upper Kellwasser event.

Bedrock Geology and Asbestos Deposits of the Upper Missisquoi Valley and Vicinity, Vermont

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Cady, Wallace Martin; Albee, Arden Leroy; Chidester, A.H.

1963-01-01

The upper Missisquoi Valley and vicinity as described in this report covers an area of about 250 square miles at the headwaters of the Missisquoi River in north-central Vermont. About 90 percent of the area is forested and the remainder is chiefly farm land. The topography reflects the geologic structure and varied resistance of the bedrock to erosion. Most of the area is on the east limb of the Green Mountain anticlinorium, which is the principal structural feature of Vermont. The bedrock is predominantly sedimentary and volcanic rock that has been regionally metamorphosed. It was intruded before metamorphism by mafic and ultramafic igneous rocks, and after metamorphism by felsic and mafic igneous rocks. The metamorphosed sedimentary and volcanic rocks range in age from Cambrian(?) to Middle Silurian, the intrusive igneous rocks from probably Late Ordovician to probably late Permian. Metamorphism and principal folding in the region occurred in Middle Devonian time. The metamorphosed sedimentary and volcanic rocks make up a section at least 25,000 feet thick and can be divided into nine formations. The Hazens Notch formation of Cambrian(?) and Early Cambrian age is characterized by carbonaceous schist. It is succeeded in western parts of the area by the Jay Peak formation of Early Cambrian age, which is chiefly a schist that is distinguished by the general absence of carbonaceous zones; in central parts of the area the Hazens Notch formation is followed by the Belvidere Mountain amphibolite, probably the youngest of the formations of Early Cambrian age. The Ottauquechee formation, composed of carbonaceous phyllite and quartzite, and phyllitic graywacke, is of Middle Cambrian age. The Stowe formation of Late Cambrian(?) and Early(?) Ordovician age overlies the Ottauquechee and is predominantly noncarbonaceous schist, though it also contains greenstone and carbonaceous schist and phyllite. The Umbrella Hill formation of Middle Ordovician age is characteristically a

Upper limits to trace constituents in Jupiter's atmosphere from an analysis of its 5 micrometer spectrum

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Treffers, R. R.; Larson, H. P.; Fink, U.; Gautier, T. N.

1978-01-01

A high-resolution spectrum of Jupiter at 5 micrometers recorded at the Kuiper Airborne Observatory is used to determine upper limits to the column density of 19 molecules. The upper limits to the mixing ratios of SiH4, H2S, HCN, and simple hydrocarbons are discussed with respect to current models of Jupiter's atmosphere. These upper limits are compared to expectations based upon the solar abundance of the elements. This analysis permits upper limit measurements (SiH4), or actual detections (GeH4) of molecules with mixing ratios with hydrogen as low as 10 to the minus 9th power. In future observations at 5 micrometers the sensitivity of remote spectroscopic analyses should permit the study of constituents with mixing ratios as low as 10 to the minus 10th power, which would include the hydrides of such elements as Sn and As as well as numerous organic molecules.

Controls on organic carbon distribution in sediments from the eastern Arabian Sea margin

Digital Repository Service at National Institute of Oceanography (India)

Thamban, M.; Rao, V.P.; Raju, S.V.

Sediment cores from the upper continental slope of the eastern Arabian Sea have high organic carbon (OC), CaCO sub(3), and sand content at the top. The values decrease with increasing depth in the Holocene and Upper Pleistocene. Topographic highs...

Upper digestive stenosis due to a hydatid cyst of the liver.

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Jarrar, Mohamed Salah; Ben Hadj Khalifa, Mohamed Habib; Toumi, Radhouane; Ghrissi, Rafik; Elghali, Mohamed Amine; Khenissi, Abdelmajid; Hamila, Fehmi; Letaief, Rached

2015-03-01

The complications of the hydatid cyst of the liver are dominated by infection and rupture. The compression of adjacent organs (mainly the inferior vena cava, the portal vein and the bile ducts) can be seen, when the cyst is located in the dome, in the hilum or within the hepatic parenchyma. Upper digestive stenosis by compression of the duodenum by the hydatid cyst is an exceptional complication. A 63 year-old patient had, for two months, upper digestive stenosis associated with a sensation of weight in the right hypochondrium. Digestive endoscopy showed an extrinsic compression of the second portion of the duodenum. Biopsies were negative. Abdominal CT showed up a hydatid cyst in the segment VI of the liver, adhering to the duodenum, with an exo-vesiculation compressing it. The patient was operated on: There was a hydatid cyst of the right lateral sector compressing the duodenum. A partial intralamellar pericystectomy was performed. Hydatid cyst of the liver, a parasitic disease described as benign, may give mechanical complications related to compression of adjacent organs (especially the bile ducts and veins). Compression of the digestive tract is exceptional. This is due to the proximity of the cyst to the duodenum and the thickness of the cyst wall.

Assessing the dynamics of the upper soil layer relative to soil management practices

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Hatfield, J.; Wacha, K.; Dold, C.

2017-12-01

The upper layer of the soil is the critical interface between the soil and the atmosphere and is the most dynamic in response to management practices. One of the soil properties most reflective to changes in management is the stability of the aggregates because this property controls infiltration of water and exchange of gases. An aggregation model has been developed based on the factors that control how aggregates form and the forces which degrade aggregates. One of the major factors for this model is the storage of carbon into the soil and the interaction with the soil biological component. To increase soil biology requires a stable microclimate that provides food, water, shelter, and oxygen which in turn facilitates the incorporation of organic material into forms that can be combined with soil particles to create stable aggregates. The processes that increase aggregate size and stability are directly linked the continual functioning of the biological component which in turn changes the physical and chemical properties of the soil. Soil aggregates begin to degrade as soon as there is no longer a supply of organic material into the soil. These processes can range from removal of organic material and excessive tillage. To increase aggregation of the upper soil layer requires a continual supply of organic material and the biological activity that incorporates organic material into substances that create a stable aggregate. Soils that exhibit stable soil aggregates at the surface have a prolonged infiltration rate with less runoff and a gas exchange that ensures adequate oxygen for maximum biological activity. Quantifying the dynamics of the soil surface layer provides a quantitative understanding of how management practices affect aggregate stability.

Occurrence of Organic Compounds and Trace Elements in the Upper Passaic and Elizabeth Rivers and Their Tributaries in New Jersey, July 2003 to February 2004: Phase II of the New Jersey Toxics Reduction Workplan for New York-New Jersey Harbor

Science.gov (United States)

Wilson, Timothy P.; Bonin, Jennifer L.

2008-01-01

Samples of surface water and suspended sediment were collected from the Passaic and Elizabeth Rivers and their tributaries in New Jersey from July 2003 to February 2004 to determine the concentrations of selected chlorinated organic and inorganic constituents. This sampling and analysis was conducted as Phase II of the New York-New Jersey Harbor Estuary Workplan?Contaminant Assessment and Reduction Program (CARP), which is overseen by the New Jersey Department of Environmental Protection. Phase II of the New Jersey Workplan was conducted to define upstream tributary and point sources of contaminants in those rivers sampled during Phase I work, with special emphasis on the Passaic and Elizabeth Rivers. Samples were collected from three groups of tributaries: (1) the Second, Third, and Saddle Rivers; (2) the Pompton and upper Passaic Rivers; and (3) the West Branch and main stem of the Elizabeth River. The Second, Third, and Saddle Rivers were sampled near their confluence with the tidal Passaic River, but at locations not affected by tidal flooding. The Pompton and upper Passaic Rivers were sampled immediately upstream from their confluence at Two Bridges, N.J. The West Branch and the main stem of the Elizabeth River were sampled just upstream from their confluence at Hillside, N.J. All tributaries were sampled during low-flow discharge conditions using the protocols and analytical methods for organic constituents used in low-flow sampling in Phase I. Grab samples of streamflow also were collected at each site and were analyzed for trace elements (mercury, methylmercury, cadmium, and lead) and for suspended sediment, particulate organic carbon, and dissolved organic carbon. The measured concentrations and available historical suspended-sediment and stream-discharge data (where available) were used to estimate average annual loads of suspended sediment and organic compounds in these rivers. Total suspended-sediment loads for 1975?2000 were estimated using rating

Genetic and stratigraphic significance of the Upper Devonian Frasnian Z Marker, west-central Alberta

Energy Technology Data Exchange (ETDEWEB)

Wendte, J. [Geological Survey of Canada, Calgary, AB (Canada); Stoakes, F. [Stoakes Consulting Group Ltd., Calgary, AB (Canada); Bosman, M. [Canadian Hunter Exploration Ltd., Calgary, AB (Canada); Bernstein, L. [Talisman Energy Inc., Calgary, AB (Canada)

1995-12-01

The stratigraphic model from the west-central Alberta basin was provided. It defined the Z Marker as a distinctive and widespread wireline log marker within the thick Frasnian Ireton shale basin succession. The marker represents an interval of condensed sedimentation and corresponds to an abrupt change from a calcareous signature below to an argillaceous character above. Toward the shelf, in the West Pembina area, the Z Marker correlates to a level within a conformable succession of nodular lime wackestones and corresponds to the base of a depositional cycle near the middle of the Lobstick member of the Nisku Formation. Further shelfward, the Z Marker continues as a well-defined log marker until the Nisku shelf margin. The stratigraphic significance of the Z Marker in delineating various oil bearing formations in Alberta were explained in great detail. The correct recognition and correlation of this marker was claimed to permit an understanding of basin evolution beyond that discernable from the existing lithostratigraphic nomenclature alone. 17 refs., 13 figs.

Radiology trainer. Torso, internal organs and vessels. 2. ed.

International Nuclear Information System (INIS)

Staebler, Axel; Erlt-Wagner, Birgit

2013-01-01

The radiology training textbook is based on case studies of the clinical experience, including radiological imaging and differential diagnostic discussion. The scope of this volume covers the torso, internal organs and vessels. The following issues are discussed: lungs, pleura, mediastinum; heart and vascular system; upper abdomen organs; gastrointestinal tract; urogenital system.

Possibility of organic mineral water 'Naftusia Zbrutschanska' helps in correction of immune system with of

International Nuclear Information System (INIS)

Raksha-Slyusareva, E.A.; Slyusarev, A.A.; Malygina, V.D.

2005-01-01

Changing of hemato-immunological state of Chernobyl clean uppers, and conventional heals population, living in Donbass eco crisis region under influence of organic mineral water 'Naftusia Zbrutschanska' was detected. It was registries that including of organic mineral water 'Naftusia Zbrutschanska' in to the complex treatment of Chernobyl clean uppers or for immune correction of conventional heals population corrected not only red and white blood, but immunological state too. Especial after course of the organic mineral water 'Naftusia Zbrutschanska' the considers of lymphocyte populations, restarted to normal date or with tendency to norm

EUV-VUV photochemistry in the upper atmospheres of Titan and the early Earth

Science.gov (United States)

Imanaka, H.; Smith, M. A.

2010-12-01

Titan, the organic-rich moon of Saturn, possesses a thick atmosphere of nitrogen, globally covered with organic haze layers. The recent Cassini’s INMS and CAPS observations clearly demonstrate the importance of complex organic chemistry in the ionosphere. EUV photon radiation is the major driving energy source there. Our previous laboratory study of the EUV-VUV photolysis of N2/CH4 gas mixtures demonstrates a unique role of nitrogen photoionization in the catalytic formation of complex hydrocarbons in Titan’s upper atmosphere (Imanaka and Smith, 2007, 2009). Such EUV photochemistry could also have played important roles in the formation of complex organic molecules in the ionosphere of the early Earth. It has been suggested that the early Earth atmosphere may have contained significant amount of reduced species (CH4, H2, and CO) (Kasting, 1990, Pavlov et al., 2001, Tian et al., 2005). Recent experimental study, using photon radiation at wavelengths longer than 110 nm, demonstrates that photochemical organic haze could have been generated from N2/CO2 atmospheres with trace amounts of CH4 or H2 (Trainer et al., 2006, Dewitt et al., 2009). However, possible EUV photochemical processes in the ionosphere are not well understood. We have investigated the effect of CO2 in the possible EUV photochemical processes in simulated reduced early Earth atmospheres. The EUV-VUV photochemistry using wavelength-tunable synchrotron light between 50 - 150 nm was investigated for gas mixtures of 13CO2/CH4 (= 96.7/3.3) and N2/13CO2/CH4 (= 90/6.7/3.3). The onsets of unsaturated hydrocarbon formation were observed at wavelengths shorter than the ionization potentials of CO2 and N2, respectively. This correlation indicates that CO2 can play a similar catalytic role to N2 in the formation of heavy organic species, which implies that EUV photochemistry might have significant impact on the photochemical generation of organic haze layers in the upper atmosphere of the early Earth.

Avulsions, channel evolution and floodplain sedimentation rates of the anastomosing upper Columbia River, British Columbia, Canada

NARCIS (Netherlands)

Makaske, B.; Smith, D.G.; Berendsen, H.J.A.

2002-01-01

Ages of channels of the anastomosing upper Columbia River, south-eastern British Columbia, Canada, were investigated in a cross-valley transect by C-14 dating of subsurface floodplain organic material from beneath levees. The avulsion history within the transect was deduced from these data, and

Evolution of an outage management organization in a small utility

International Nuclear Information System (INIS)

Oubre, R.P.; Shetler, J.

1985-01-01

Six refueling outages with a number of major equipment failure outages have taught Rancho Seco management three main items. One is that a dedicated management organization must be formed for the purpose of controlling work functions at Rancho Seco. This dedicated organization must have the experience of the plant and not have the responsibility for the actual maintenance. Second, upper management within a power plant must get directly involved in the outage. Upper management must show their presence, give input, and be available when needed. The third item learned is that the scheduling organization must be adequately staffed. Although Rancho Seco completed a refueling outage in 1978 within only 36 days, additional inspection requirements due to regulatory changes and/or previous equipment failures requiring follow-up actions would place the shortest possible outage today at approx.70 days. The only way an organization can keep this outage time down is with the proper scheduling of the resources and the timely coordination of activities to reduce conflicts

Groundwater-derived nutrient inputs to the Upper Gulf of Thailand

Science.gov (United States)

Burnett, William C.; Wattayakorn, Gullaya; Taniguchi, Makoto; Dulaiova, Henrieta; Sojisuporn, Pramot; Rungsupa, Sompop; Ishitobi, Tomotoshi

2007-01-01

We report here the first direct measurements of nutrient fluxes via groundwater discharge into the Upper Gulf of Thailand. Nutrient and standard oceanographic surveys were conducted during the wet and dry seasons along the Chao Phraya River, Estuary and out into the Upper Gulf of Thailand. Additional measurements in selected near-shore regions of the Gulf included manual and automatic seepage meter deployments, as well as nutrient evaluations of seepage and coastal waters. The river transects characterized the distribution of biogeochemical parameters in this highly contaminated urban environment. Seepage flux measurements together with nutrient analyses of seepage fluids were used to estimate nutrient fluxes via groundwater pathways for comparison to riverine fluxes. Our findings show that disseminated seepage of nutrient-rich mostly saline groundwater into the Upper Gulf of Thailand is significant. Estimated fluxes of dissolved inorganic nitrogen (DIN) supplied via groundwater discharge were 40-50% of that delivered by the Chao Phraya River, inorganic phosphate was 60-70%, and silica was 15-40%. Dissolved organic nitrogen (DON) and phosphorus (DOP) groundwater fluxes were also high at 30-40% and 30-130% of the river inputs, respectively. These observations are especially impressive since the comparison is being made to the river that is the largest source of fresh water into the Gulf of Thailand and flows directly through the megacity of Bangkok with high nutrient loadings from industrial and domestic sources.

Upper Hiwassee River Basin reservoirs 1989 water quality assessment

International Nuclear Information System (INIS)

Fehring, J.P.

1991-08-01

The water in the Upper Hiwassee River Basin is slightly acidic and low in conductivity. The four major reservoirs in the Upper Hiwassee River Basin (Apalachia, Hiwassee, Chatuge, and Nottely) are not threatened by acidity, although Nottely Reservoir has more sulfates than the other reservoirs. Nottely also has the highest organic and nutrient concentrations of the four reservoirs. This results in Nottely having the poorest water clarity and the most algal productivity, although clarity as measured by color and secchi depths does not indicate any problem with most water use. However, chlorophyll concentrations indicate taste and odor problems would be likely if the upstream end of Nottely Reservoir were used for domestic water supply. Hiwassee Reservoir is clearer and has less organic and nutrient loading than either of the two upstream reservoirs. All four reservoirs have sufficient algal activity to produce supersaturated dissolved oxygen conditions and relatively high pH values at the surface. All four reservoirs are thermally stratified during the summer, and all but Apalachia have bottom waters depleted in oxygen. The very short residence time of Apalachia Reservoir, less than ten days as compared to over 100 days for the other three reservoirs, results in it being more riverine than the other three reservoirs. Hiwassee Reservoir actually develops three distinct water temperature strata due to the location of the turbine intake. The water quality of all of the reservoirs supports designated uses, but water quality complaints are being received regarding both Chatuge and Nottely Reservoirs and their tailwaters

NEW PALEOMAGNETIC DATA ON THE SILURIAN AND DEVONIAN SEDIMENTARY ROCKS FROM PODOLIA, SW UKRAINE, AND KINEMATICS OF THE EAST EUROPEAN PLATFORM IN THE MIDDLE PALEOZOIC

Directory of Open Access Journals (Sweden)

V. G. Bakhmutov

2014-01-01

Full Text Available Paleomagnetic data are the priority source of information for global paleotectonic reconstructions representing horizontal movements of the crustal blocks. Upon receipt of new paleomagnetic data, kinematic models of the East European platform in the Paleozoic are regularly revised and improved. The article presents results of the paleomagnetic study of sedimentary gray-colored and red beds of the Silurian and Lower Devonian sequences located in the Dniester river basin, Podolia region, SW Ukraine. The study covered 17 outcrops that are stratigraphically correlated with the Wenlock, Ludlow, Pridoli states of the Sillurian and the Lochkovian stage of the Devon. Over 400 samples of grey limestone, argillite, dolomite, red limestone and sandstone were analyzed, and two components of natural remnant magnetization (NRM were revealed. The first component with SSW declination and negative inclination is revealed in the majority of the samples during AF- and T-magnetic cleaning. Its pole positions, that are calculated separately for each series, are trending to the Permian segment of the apparent polar wander path (APWP published by Torsvik et al. [2012] for Baltica / Stable Europe. Considering its chemical origin, this NRM component is related to formation of authigenic minerals due to rock remagnetization. The second component is revealed only in some samples taken from the red beds (during thermal demagnetization in the range of unblocking temperatures from 590 to 690 °С and in few samples of grey limestone (in AF fields from 30 to 70 mT or in the range of unblocking temperatures from 300 to 460 °С. This component has SW declination and positive inclination, goes to the origin of coordinates of the diagrams, and has all the indicators of primary magnetization of sediments. Calculated positions of the poles (0 ºS and 329 ºE for grey limestone of the Tiverskaya series, 2.3 °S and 338.4 °E for red beds of the Dniestrovskaya series, etc. are well

Commercial gaming devices for stroke upper limb rehabilitation: a systematic review.

Science.gov (United States)

Thomson, Katie; Pollock, Alex; Bugge, Carol; Brady, Marian

2014-06-01

Rehabilitation using commercial gaming devices is a new concept for stroke care. Commercial gaming devices such as Nintendo Wii or Sony PlayStation encourage high repetition of arm movements and are being introduced into some clinical settings. The evidence base for gaming use in rehabilitation is growing rapidly and there is a need to systematically synthesise research. Our review aims to integrate evidence on how gaming is being used, explore patient/therapist experience and synthesise evidence of effectiveness. An integrative systematic review was undertaken searching Cochrane Central Register of Controlled Trials (2013), Medline (2013), Embase (2013) and twelve additional databases. Two review authors independently selected studies based on pre-defined inclusion criteria, extracted data and assessed risk of bias. Nineteen studies including 215 patients met inclusion criteria. Studies were typically small scale feasibility studies using a range of research designs, limiting the ability to reach generalised conclusions. Results have been tabulated (activities of daily living, upper limb function/ movement) and qualitative themes identified. Findings suggest that most patients enjoy using commercial gaming and can tolerate 180 mins per week without significant adverse effects. A trend towards improvement was noted for upper limb function/ movement. Few studies recorded outcomes related to activities of daily living or focused on understanding patients' experiences of this intervention. Commercial gaming can provide high intensity upper limb practice however there is insufficient high quality evidence to reach generalisable conclusions about risks or benefits on activities of daily living or upper limb function/movement. © 2014 The Authors. International Journal of Stroke © 2014 World Stroke Organization.

Upper gastrointestinal bleeding in patients with CKD.

Science.gov (United States)

Liang, Chih-Chia; Wang, Su-Ming; Kuo, Huey-Liang; Chang, Chiz-Tzung; Liu, Jiung-Hsiun; Lin, Hsin-Hung; Wang, I-Kuan; Yang, Ya-Fei; Lu, Yueh-Ju; Chou, Che-Yi; Huang, Chiu-Ching

2014-08-07

Patients with CKD receiving maintenance dialysis are at risk for upper gastrointestinal bleeding. However, the risk of upper gastrointestinal bleeding in patients with early CKD who are not receiving dialysis is unknown. The hypothesis was that their risk of upper gastrointestinal bleeding is negatively linked to renal function. To test this hypothesis, the association between eGFR and risk of upper gastrointestinal bleeding in patients with stages 3-5 CKD who were not receiving dialysis was analyzed. Patients with stages 3-5 CKD in the CKD program from 2003 to 2009 were enrolled and prospectively followed until December of 2012 to monitor the development of upper gastrointestinal bleeding. The risk of upper gastrointestinal bleeding was analyzed using competing-risks regression with time-varying covariates. In total, 2968 patients with stages 3-5 CKD who were not receiving dialysis were followed for a median of 1.9 years. The incidence of upper gastrointestinal bleeding per 100 patient-years was 3.7 (95% confidence interval, 3.5 to 3.9) in patients with stage 3 CKD, 5.0 (95% confidence interval, 4.8 to 5.3) in patients with stage 4 CKD, and 13.9 (95% confidence interval, 13.1 to 14.8) in patients with stage 5 CKD. Higher eGFR was associated with a lower risk of upper gastrointestinal bleeding (P=0.03), with a subdistribution hazard ratio of 0.93 (95% confidence interval, 0.87 to 0.99) for every 5 ml/min per 1.73 m(2) higher eGFR. A history of upper gastrointestinal bleeding (Pupper gastrointestinal bleeding risk. In patients with CKD who are not receiving dialysis, lower renal function is associated with higher risk for upper gastrointestinal bleeding. The risk is higher in patients with previous upper gastrointestinal bleeding history and low serum albumin. Copyright © 2014 by the American Society of Nephrology.

Ecological traps in shallow coastal waters-Potential effect of heat-waves in tropical and temperate organisms.

Directory of Open Access Journals (Sweden)

Catarina Vinagre

Full Text Available Mortality of fish has been reported in tide pools during warm days. That means that tide pools are potential ecological traps for coastal organisms, which happen when environmental changes cause maladaptive habitat selection. Heat-waves are predicted to increase in intensity, duration and frequency, making it relevant to investigate the role of tide pools as traps for coastal organisms. However, heat waves can also lead to acclimatization. If organisms undergo acclimatization prior to being trapped in tide pools, their survival chances may increase. Common tide pool species (46 species in total were collected at a tropical and a temperate area and their upper thermal limits estimated. They were maintained for 10 days at their mean summer sea surface temperature +3°C, mimicking a heat-wave. Their upper thermal limits were estimated again, after this acclimation period, to calculate each species' acclimation response. The upper thermal limits of the organisms were compared to the temperatures attained by tide pool waters to investigate if 1 tide pools could be considered ecological traps and 2 if the increase in upper thermal limits elicited by the acclimation period could make the organisms less vulnerable to this threat. Tropical tide pools were found to be ecological traps for an important number of common coastal species, given that they can attain temperatures higher than the upper thermal limits of most of those species. Tide pools are not ecological traps in temperate zones. Tropical species have higher thermal limits than temperate species, but lower acclimation response, that does not allow them to survive the maximum habitat temperature of tropical tide pools. This way, tropical coastal organisms seem to be, not only more vulnerable to climate warming per se, but also to an increase in the ecological trap effect of tide pools.

Comparative morphology, histology and growth of the dental plates of the Devonian dipnoan Chirodipterus.

Science.gov (United States)

Smith, M M; Campbell, K S

1987-10-14

The dental plates of the Devonian lungfish Chirodipterus australis Miles (Osteichthyes; Dipnoi) are shown to have achieved their characteristic morphology by a growth process different from that assumed for the plates of genera such as Dipterus. Each plate was thickened by the addition of layers of bone that also extended the plate labially, thus providing the base on which and into which dentine grew. Distinctive features of the dentition are: (a) labial increase of the dentine mass by the addition of blister-like denticles of simple enamel-covered dentine, which is initially ingrown by pleromic dentine and subsequently resorbed and replaced by petrodentine; (b) increase in the midline by a similar process that results in the addition of one (or possibly two) new ridges; (c) resorption of the posterior edge of the pterygoid plates and the posterior and posteromedial edges of the prearticular plates, with subsequent development over the resorbed surfaces of several generations of simple regenerative dentine; (d) resorption and redeposition of pleromic dentine and bone in a triangular region posteromedially on the pterygoid plates; (e) the formation of tuberosities that simulate teeth at a short distance in from the labial edge, by four processes: formation of an undulating plate margin, differential growth of petrodentine (hard compact dentine) within the pulp cavity, differential wear of the petrodentine and the adjacent bone plus pleromic dentine, and slightly greater growth of the petrodentine towards the occlusal surface relative to the adjacent bone and dentine; (f) expansion of the large flat surfaces of the plates by gradual replacement of the bone and dentine at the proximal ends of the furrows and also by the development of linkages of petrodentine across the furrows; (g) development of isolated tuberosities on the flat posterolateral parts of the plates. The petrodentine of the ridges, tuberosities and plateaus of the plates is indistinguishable

Right upper quadrant pain

International Nuclear Information System (INIS)

Ralls, P.W.; Colletti, P.M.; Boswell, W.D. Jr.; Halls, J.M.

1984-01-01

Historically, assessment of acute right upper quadrant abdominal pain has been a considerable clinical challenge. While clinical findings and laboratory data frequently narrow the differential diagnosis, symptom overlap generally precludes definitive diagnosis among the various diseases causing acute right upper quadrant pain. Fortunately, the advent of newer diagnostic imaging modalities has greatly improved the rapidity and reliability of diagnosis in these patients. An additional challenge to the physician, with increased awareness of the importance of cost effectiveness in medicine, is to select appropriate diagnostic schema that rapidly establish accurate diagnoses in the most economical fashion possible. The dual goals of this discussion are to assess not only the accuracy of techniques used to evaluate patients with acute right upper quadrant pain, but also to seek out cost-effective, coordinated imaging techniques to achieve this goal

The organization of the posterior parietal cortex devoted to upper limb actions: An fMRI study

Science.gov (United States)

Ferri, Stefania; Rizzolatti, Giacomo

2015-01-01

Abstract The present fMRI study examined whether upper‐limb action classes differing in their motor goal are encoded by different PPC sectors. Action observation was used as a proxy for action execution. Subjects viewed actors performing object‐related (e.g., grasping), skin‐displacing (e.g., rubbing the skin), and interpersonal upper limb actions (e.g., pushing someone). Observation of the three action classes activated a three‐level network including occipito‐temporal, parietal, and premotor cortex. The parietal region common to observing all three action classes was located dorsally to the left intraparietal sulcus (DIPSM/DIPSA border). Regions specific for observing an action class were obtained by combining the interaction between observing action classes and stimulus types with exclusive masking for observing the other classes, while for regions considered preferentially active for a class the interaction was exclusively masked with the regions common to all observed actions. Left putative human anterior intraparietal was specific for observing manipulative actions, and left parietal operculum including putative human SII region, specific for observing skin‐displacing actions. Control experiments demonstrated that this latter activation depended on seeing the skin being moved and not simply on seeing touch. Psychophysiological interactions showed that the two specific parietal regions had similar connectivities. Finally, observing interpersonal actions preferentially activated a dorsal sector of left DIPSA, possibly the homologue of ventral intraparietal coding the impingement of the target person's body into the peripersonal space of the actor. These results support the importance of segregation according to the action class as principle of posterior parietal cortex organization for action observation and by implication for action execution. Hum Brain Mapp 36:3845–3866, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley

New paleomagnetic data from late Paleozoic sedimentary rocks of Novaya Zemlya Archipelago: tectonic implications

Science.gov (United States)

Abashev, Victor V.; Metelkin, Dmitry V.; Mikhaltsov, Nikolay E.; Vernikovsky, Valery A.; Matushkin, Nikolay Yu.

2017-04-01

New paleomagnetic data for Novaya Zemlya archipelago were obtained by processing the samples collection gathered during the 2014 field season. The paleomagnetic directions and paleomagnetic poles were determined from the Paleozoic sedimentary complexes located on the Southern Island (Upper Permian) and the Northern Island (Lower and Upper Devonian, Upper Carboniferous) of the archipelago. Positive fold and reversal tests indicate that the isolated paleomagnetic directions correspond to the primary magnetization components. The corresponding paleomagnetic pole are in good agreement with poles obtained earlier in the 1980s by E.L. Gurevich and I.A. Pogarskaya. Considering the confidence ovals, the paleomagnetic poles obtained for the sites of the Northern Island are located close to the corresponding path segment of the APWP of Europe. This means that at least since the early Devonian, the northern part of Novaya Zemlya Archipelago had a position that was close to its current position relatively to the Arctic margin of Europe and has not undergone significant shifts or rotations. However, the upper Permian paleomagnetic pole for the Southern Island is very different from the corresponding part of the European APWP. We are considering this pole position within a model, involving significant intraplate movement between the structures of the European and Siberian tectonic provinces until the Late Cretaceous. The sinistral strike-slips inferred by the model could have caused or were accompanying the opening of the Mesozoic rift system in Western Siberia. This event has reached its maximum within the South Kara basin and resulted in the north-westward (in geographic coordinates) displacement of the southern part of the Novaya Zemlya Archipelago in relation to the Arctic margin of Europe and in the deformation of the Pay-Khoy-Novaya Zemlya margin, which caused its modern curved form. The study was supported by the Russian Science Foundation, grant No. 14-37-00030 and the

Upper plenum mixing in a BWR

International Nuclear Information System (INIS)

Alamgir, M.; Andersen, J.G.M.; Parameswaran, V.

1984-01-01

A model for the emergency core cooling injection into the upper plenum of a boiling water reactor has been formulated and implemented into the TRACB02 computer program. The model consists of a spray model and a submerged jet model. The submerged jet model is used when the spray nozzles are covered by a two-phase mixture, and the spray model is used when the nozzles are uncovered. The upper plenum model has been assessed by comparison to an upper plenum mixing test in the Steam Sector Test Facility. It is found that the model accurately predicts the phenomena in the upper plenum of a boiling water reactor

The Cambrian to Devonian odyssey of the Brabant Massif within Avalonia: A review with new zircon ages, geochemistry, Sm-Nd isotopes, stratigraphy and palaeogeography

Science.gov (United States)

Linnemann, Ulf; Herbosch, Alain; Liégeois, Jean-Paul; Pin, Christian; Gärtner, Andreas; Hofmann, Mandy

2012-05-01

This study provides an up-to-date and comprehensive review of the Early Palaeozoic evolution of the Brabant Massif belonging to the Anglo-Brabant Deformation Belt. Situated at the southeastern side of Avalonia microplate, it is the only well-known part of the northern passive margin of the Rheic Ocean. The Cambrian-Silurian sedimentary pile is > 13 km thick, with > 9 km for the Cambrian only. The unraveling of this continuous registration reflects the successive rifting and drifting of Avalonia from the Gondwana mainland, followed by soft-collisional processes with Baltica and finally the formation of Laurussia. Based on recently established detailed stratigraphy, sedimentology and basin development, on U-Pb LA-ICP-MS analyses of igneous and detrital zircon grains along with geochemical data including Sm-Nd isotopes, a new geodynamic and palaeogeographic evolution is proposed. Brabant Megasequence 1 (lower Cambrian to lowermost Ordovician, > 9 km thick) represents an embayment of the peri-Gondwanan rift from which the Rheic Ocean has evolved. Detrital zircon ages demonstrate that the Brabant is a typical peri-Gondwanan terrane with a major Pan-African (Neoproterozoic age) and a mixed West African and Amazonian source (Palaeoproterozoic, Archaean and some Mesoproterozoic age). The transition towards the Avalonia drifting is marked by an unconformity and a short volcanic episode. The northward drift of Avalonia towards Baltica is recorded by the Megasequence 2 (Middle to Upper Ordovician, 1.3 km thick). The source for Mesoproterozoic zircons vanished, as the result of the Rheic Ocean opening and the isolation from Amazonian sources. The transition to Megasequence 3 is marked by a drastic change in palaeobathymetry and an important (sub)volcanic episode during a tectonic instability period (460-430 Ma), reflecting the Avalonia-Baltica soft docking as also shown by the reappearance of Mesoproterozoic detrital zircons, typical of Baltica. Unradiogenic Nd isotope

Geochemical imprint of depositional conditions on organic matter in laminated-Bioturbated interbeds from fine-grained marine sequences

Science.gov (United States)

Pratt, L.M.; Claypool, G.E.; King, J.D.

1986-01-01

Laminated organic-rich shales are interbedded at a scale of centimeters to a few meters with bioturbated organic-poor mudstones or limestones in some fine-grained marine sequences. We have analyzed the organic matter in pairs of laminated/bioturbated interbeds from Cretaceous and Devonian rocks deposited in epicontinental and oceanic settings for the purpose of studying the influence of depositional and early diagenetic environment on the organic geochemical properties of marine shales. Results of these analyses indicate that for rocks that are still in a diagenetic stage of thermal alteration, the relative abundance of biomarker compounds and specific biomarker indices can be useful indicators of depositional and early diagenetic conditions. Pristane/phytane ratios are generally highest for laminated rocks from epicontinental basins and appear to reflect the input of isoprenoid precursors more than oxygenated versus anoxic depositional conditions. The thermally immature laminated rocks are characterized by relatively high contents of 17??(H), 21??(H)-hopanes, hopenes, sterenes and diasterenes, and by strong predominance of the 22R over 22S homohopane isomers. Thermally immature bioturbated samples are characterized by absence of the ??,??-hopanes, by low contents of both saturated and unsaturated polycyclic hydrocarbons, and by slight or no predominance of the 22R over 22S homohopane isomers. There are less obvious compositional differences between the saturated hydrocarbons in the laminated and bioturbated units from the thermally mature sequences. For both the thermally mature and immature laminated samples, the degree of isomerization at the 22C position for hopanes and at the 20C position for steranes is generally consistent with the degree of thermal maturity interpreted from other properties of the organic matter. The bioturbated samples, however, exhibit inconsistent and anomalously high degrees of isomerization for the homohopanes, resulting either from

Sorption of cesium, strontium, and technetium onto organic-extracted shales

International Nuclear Information System (INIS)

Ho, P.C.

1992-01-01

The sorption of Cs(I), Sr(II), and Tc(VII) onto organic-extracted shales from synthetic brine groundwaters and from 0.03-M NaHCO 3 solution under oxid conditions at room temperature has been studied. The shale samples used in this study were Pumpkin Valley, Upper Dowelltown, Pierre and Green River Formation Shales. The organic content of these shales ranges from less than 2 wt% to 13 wt%. Soxhlet extraction with chloroform and a mixture of chloroform and methanol removed 0.07 to 5.9 wt% of the total organic matter from these shales. In comparison with the results of sorption of these three metal ions onto the corresponding untreated shales, it was observed that there were moderate to significant sorption decreases of Cs(I) and Sr(II) on all four organic-extracted shale samples and moderate sorption decrease of Tc(VII) on the organic-extracted Pumpkin Valley, Pierre, and Green River Shale samples, but only moderate sorption increases of Tc(VII) on the organic-extracted Upper Dowelltown Shale samples from the brine groundwaters. Nevertheless, sorption of Cs(I), Sr(II), and Tc(VII) on all four organic-extracted shale samples from the bicarbonate solution in most cases did not show a consistent pattern. (orig.)

Comparison of CT findings with upper GI series and surgical findings

Energy Technology Data Exchange (ETDEWEB)

Hong, Jin Kyo; Suh, Soo Jhi; Kim, Soon Yong [School of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

1981-09-15

The authors made comparative studies of CT findings with upper GI series and surgical findings in 20 cases of histologically proven gastric cancers. The identification of chickening of gastric wall and local and remote metastasis by CT was thought to be great value in treatment planning and prediction of prognosis of the patients. The results were as follows: 1. Of 20 cases, 19 cases demonstrated thickening of gastric wall. Among 3 cases suggested as early cancer on upper GI series, 2 cases demonstrated thickened gastric wall on CT and it was proved to be advanced cancer at surgery. 2. Out of 8 cases showed no definite metastasis on CT, 4 cases had malignant infiltration histologically in the regional lymph nodes. But they were less than 1.5 cm in diameter. 3. The frequency order of remote metastasis found by CT was pancreas, liver, left adrenal gland and lung in organs and retroperitoneal, retrocrural and regional nodes in lymph nodes.

Fuzzy upper bounds and their applications

Energy Technology Data Exchange (ETDEWEB)

Soleimani-damaneh, M. [Department of Mathematics, Faculty of Mathematical Science and Computer Engineering, Teacher Training University, 599 Taleghani Avenue, Tehran 15618 (Iran, Islamic Republic of)], E-mail: soleimani_d@yahoo.com

2008-04-15

This paper considers the concept of fuzzy upper bounds and provides some relevant applications. Considering a fuzzy DEA model, the existence of a fuzzy upper bound for the objective function of the model is shown and an effective approach to solve that model is introduced. Some dual interpretations are provided, which are useful for practical purposes. Applications of the concept of fuzzy upper bounds in two physical problems are pointed out.

Safety and Mission Assurance for In-House Design Lessons Learned from Ares I Upper Stage

Science.gov (United States)

Anderson, Joel M.

2011-01-01

This viewgraph presentation identifies lessons learned in the course of the Ares I Upper Stage design and in-house development effort. The contents include: 1) Constellation Organization; 2) Upper Stage Organization; 3) Presentation Structure; 4) Lesson-Importance of Systems Engineering/Integration; 5) Lesson-Importance of Early S&MA Involvement; 6) Lesson-Importance of Appropriate Staffing Levels; 7) Lesson-Importance S&MA Team Deployment; 8) Lesson-Understanding of S&MA In-Line Engineering versus Assurance; 9) Lesson-Importance of Close Coordination between Supportability and Reliability/Maintainability; 10) Lesson-Importance of Engineering Data Systems; 11) Lesson-Importance of Early Development of Supporting Databases; 12) Lesson-Importance of Coordination with Safety Assessment/Review Panels; 13) Lesson-Implementation of Software Reliability; 14) Lesson-Implementation of S&MA Technical Authority/Chief S&MA Officer; 15) Lesson-Importance of S&MA Evaluation of Project Risks; 16) Lesson-Implementation of Critical Items List and Government Mandatory Inspections; 17) Lesson-Implementation of Critical Items List Mandatory Inspections; 18) Lesson-Implementation of Test Article Safety Analysis; and 19) Lesson-Importance of Procurement Quality.

Reconstruction of pollution history of organic contaminants in the upper Gulf of Thailand by using sediment cores: first report from Tropical Asia Core (TACO) project.

Science.gov (United States)

Boonyatumanond, Ruchaya; Wattayakorn, Gullaya; Amano, Atsuko; Inouchi, Yoshio; Takada, Hideshige

2007-05-01

This paper reports the first reconstruction of a pollution history in tropical Asia from sediment cores. Four sediment core samples were collected from an offshore transect in the upper Gulf of Thailand and were analyzed for organic micropollutants. The cores were dated by measurement of (137)Cs and geochronometric molecular markers (linear alkylbenzenes, LABs; and tetrapropylene-type alkylbenzenes, TABs). Polychlorinated biphenyl (PCB) concentrations showed a subsurface maximum in layers corresponding to the 1970s, indicating the effectiveness of regulation of PCBs in Thailand. LAB concentrations increased over time, indicating the increase in input of sewage into the Gulf during the last 30 years. Hopanes, biomarkers of petroleum pollution, also increased over time, indicating that the inputs of automobile-derived hydrocarbons to the coastal zone has been increasing owing to the increased number of cars in Thailand since the 1950s. Polycyclic aromatic hydrocarbons (PAHs) increased in the layers corresponding to the 1950s and 1960s, probably because of the increased inputs of automobile-derived PAHs. PAH concentrations in the upper layers corresponding to the 1970s and later remained constant or increased. The absence of a subsurface maximum of PAHs contrasts with results observed in industrialized countries. This can be explained by the facts that the Thai economy did not depend on coal as an energy source in the 1960s and that economic growth has continued since the 1970s to the present. The deposition flux of PAHs and hopanes showed a dramatic offshore decrease, whereas that of LABs was uniform.

Reconstruction of pollution history of organic contaminants in the upper Gulf of Thailand by using sediment cores: First report from Tropical Asia Core (TACO) project

International Nuclear Information System (INIS)

Boonyatumanond, Ruchaya; Wattayakorn, Gullaya; Amano, Atsuko; Inouchi, Yoshio; Takada, Hideshige

2007-01-01

This paper reports the first reconstruction of a pollution history in tropical Asia from sediment cores. Four sediment core samples were collected from an offshore transect in the upper Gulf of Thailand and were analyzed for organic micropollutants. The cores were dated by measurement of 137 Cs and geochronometric molecular markers (linear alkylbenzenes, LABs; and tetrapropylene-type alkylbenzenes, TABs). Polychlorinated biphenyl (PCB) concentrations showed a subsurface maximum in layers corresponding to the 1970s, indicating the effectiveness of regulation of PCBs in Thailand. LAB concentrations increased over time, indicating the increase in input of sewage into the Gulf during the last 30 years. Hopanes, biomarkers of petroleum pollution, also increased over time, indicating that the inputs of automobile-derived hydrocarbons to the coastal zone has been increasing owing to the increased number of cars in Thailand since the 1950s. Polycyclic aromatic hydrocarbons (PAHs) increased in the layers corresponding to the 1950s and 1960s, probably because of the increased inputs of automobile-derived PAHs. PAH concentrations in the upper layers corresponding to the 1970s and later remained constant or increased. The absence of a subsurface maximum of PAHs contrasts with results observed in industrialized countries. This can be explained by the facts that the Thai economy did not depend on coal as an energy source in the 1960s and that economic growth has continued since the 1970s to the present. The deposition flux of PAHs and hopanes showed a dramatic offshore decrease, whereas that of LABs was uniform

A Study of Variations of the Branching Patterns of right Upper Lobar Bronchus by Corrosive Cast Method

Directory of Open Access Journals (Sweden)

SV Solanki

2015-06-01

Full Text Available Introduction: Respiratory system is the basic prerequisite for living organisms. So precise knowledge of normal anatomy and various dimensions of human respiratory tract is inevitable. The right upper lobe bronchus is prevailingly trifurcates into apical, anterior and posterior segmental bronchi. Material and Methods: The present study was done on 28 tracheo-bronchial casts prepared by corrosive cast method in the anatomy department of B. J. medical college of Ahmedabad, Gujarat, India from 2011 to 2013. Result and Observation: In 16 specimens (57% normal trifurcate branching pattern was seen in right upper lobar bronchus. Most common variation observed was bifurcate pattern in right upper lobar bronchus in 36% of specimens. In 7% specimens quadrivial pattern was seen in right upper lobar bronchus in which it divided into four bronchi. Conclusion: The knowledge of anatomy and variation in branching pattern of the tracheo-bronchial tree enables the physicians to recognize clinical picture and pathology of human lungs, as well as the application of therapeutic and diagnostic methods like tracheal intubation, bronchoscopy, bronchography and postural drainage etc.

Evaluation of patient doses from upper gastrointestinal tract examinations based on the dosimetry in an anthropomorphic phantom

International Nuclear Information System (INIS)

Hirofuji, Yoshiaki; Aoyama, Takahiko; Koyama, Shuji; Kawaura, Chiyo

2005-01-01

The objective of this study was to evaluate organ dose and effective dose to patients from examinations of the upper gastrointestinal (GI) tract. Absorbed doses of various tissues and organs were measured using novel photodiode dosimeters installed in an anthropomorphic phantom representing a standard Japanese adult body. The organ dose and the effective dose were assessed from the absorbed doses according to the definitions seen in the publications of the International Commission on Radiological Protection. Dose measurements were performed for each projection of the upper GI tract examination in seven procedures at four hospitals and in a mobile coach, and organ and effective doses were assessed for each procedure. Organ doses obtained in the observation areas such as the stomach, esophagus and colon were in the order of several to more than 60 mGy, though they decreased to less than 1 mGy for tissues and organs distant from the observation areas. Organ doses and effective doses differed largely according to tube voltage, filtration and tube current or mAs value of the x-ray generator used, and by examination protocol, number of images, fluoroscopy time, and imaging units such as screen/film, computed radiography, digital radiography and flat panel detector. The number of images and the fluoroscopy time were 7 and 1.5 min for the examination in the mobile coach, and 18-22 and 2-6 min in the hospitals. Evaluated effective dose for the examination in the mobile coach was 2.9 mSv, and that in the hospitals ranged from 4.0-13.4 mSv at a ratio of more than three. (author)

Long-term changes in primary production and mineralization of organic matter in the Neva Estuary (Baltic Sea)

Science.gov (United States)

Golubkov, Sergey; Golubkov, Mikhail; Tiunov, Alexei; Nikulina, Vera

2017-07-01

The Neva Estuary situated in the eastern part of the Gulf of Finland is one of the largest estuaries of the Baltic Sea. At present, heavy nutrient and organic matter loading, mainly from the Neva River and point sources in the upper estuary are the most serious environmental problem for the Neva Estuary and adjacent parts of the eastern Gulf of Finland. Long-term studies of mid-summer primary production and mineralization of organic matter were conducted in upper and middle parts of the Neva Estuary. A considerable increase of production and biomass of phytoplankton was observed in the middle part of the estuary during the last decades mainly due to an increase in biomass of cyanobacteria. However, they are mostly concentrated in the upper water layers and only a small part of them reached the near bottom water layers and may be used as a food by zoobenthos. The mineralization of organic matter in the water column was twice higher than primary production that indicates the importance of allochthonous organic matter in the carbon budget of the both parts of the estuary. The carbon isotope signature of seston and most of the zoobenthic species in the upper part of the estuary was close to the signature of allochthonous carbon leaking from watershed (- 27‰). Higher values of δ13C of seston in the upper mix layer of the Middle estuary indicate intensive primary production in mid-summer. The carbon isotopic signature of zoobenthos in this part of the estuary was also in general lower than in the Neva Bay reflected higher importance of autochthonous organic matter in food webs of the estuary.

Angiography of the upper extremity

International Nuclear Information System (INIS)

Janevski, B.K.

1982-01-01

This thesis provides a description of the technical and medical aspects of arteriography of the upper extremity and an extensive analysis of the angiographic anatomy and pathology of 750 selective studies performed in more than 500 patients. A short historical review is provided of angiography as a whole and of arteriography of the hand in particular. The method of percutaneous transfemoral catheterization of the arteries of the upper extremity and particularly the arteries of the hand is considered, discussing the problems the angiographer encounters frequently, describing the angiographic complications which may occur and emphasizing the measures to keep them to a minimum. The use of vasodilators in hand angiography is discussed. A short description of the embryological patterns persisting in the arteries of the arm is included in order to understand the congenital variations of the arteries of the upper extremity. The angiographic patterns and clinical aspects of the most common pathological processes involving the arteries of the upper extremities are presented. Special attention is paid to the correlation between angiography and pathology. (Auth.)

Green Chemistry Decision-Making in an Upper-Level Undergraduate Organic Laboratory

Science.gov (United States)

Edgar, Landon J. G.; Koroluk, Katherine J.; Golmakani, Mehrnaz; Dicks, Andrew P.

2014-01-01

A self-directed independent synthesis experiment was developed for a third-year undergraduate organic laboratory. Students were provided with the CAS numbers of starting and target compounds and devised a synthetic plan to be executed over two 4.5 h laboratory periods. They consulted the primary literature in order to develop and carry out an…

Upper gastrointestinal bleeding - state of the art.

Science.gov (United States)

Szura, Mirosław; Pasternak, Artur

2014-01-01

Upper gastrointestinal (GI) bleeding is a condition requiring immediate medical intervention, with high associated mortality exceeding 10%. The most common cause of upper GI bleeding is peptic ulcer disease, which largely corresponds to the intake of NSAIDs and Helicobacter pylori infection. Endoscopy is the essential tool for the diagnosis and treatment of active upper GI hemorrhage. Endoscopic therapy together with proton pump inhibitors and eradication of Helicobacter pylori significantly reduces rebleeding rates, mortality and number of emergency surgical interventions. This paper presents contemporary data on the diagnosis and treatment of upper gastrointestinal bleeding.

Influencing the practice and outcome in acute upper gastrointestinal haemorrhage. Steering Committee of the National Audit of Acute Upper Gastrointestinal Haemorrhage.

Science.gov (United States)

Rockall, T A; Logan, R F; Devlin, H B; Northfield, T C

1997-11-01

To assess changes in practice and outcome in acute upper gastrointestinal haemorrhage following the feedback of data, the reemphasis of national guidelines, and specific recommendations following an initial survey. A prospective, multicentre, audit cycle. Forty five hospitals from three health regions participated in two phases of the audit cycle. Phase I: 2332 patients with acute upper gastrointestinal haemorrhage; phase II: 1625 patients with upper gastrointestinal haemorrhage. Patients were evaluated with respect to management (with reference to the recommendations in the national guidelines), mortality, and length of hospital stay. Following the distribution of data from the first phase of the National Audit and the formulation of specific recommendations for improving practice, the proportion of hospitals with local guidelines or protocols for the management of upper gastrointestinal haemorrhage rose from 71% (32/45) to 91% (41/45); 12 of the 32 hospitals with guidelines during the first phase revised their guidelines following the initial survey. There was a small but significant increase in the proportion of all patients who underwent endoscopy (from 81% to 86%), the proportion who underwent endoscopy within 24 hours of admission (from 50% to 56%), and the use of central venous pressure monitoring in patients with organ failure requiring blood transfusion or those with profound shock (from 30% to 43%). There was, however, no change in the use of high dependency beds or joint medical/surgical management in high risk cases. There was no significant change in crude or risk standardised mortality (13.4% in the first phase and 14.4% in the second phase). Although many of the participating hospitals have made efforts to improve practice by producing or updating guidelines or protocols, there has been only a small demonstrable change in some areas of practice during the National Audit. The failure to detect any improvement in mortality may reflect this lack of

Vitamin K for upper gastrointestinal bleeding in people with acute or chronic liver diseases.

Science.gov (United States)

Martí-Carvajal, Arturo J; Solà, Ivan

2015-06-09

Upper gastrointestinal bleeding is one of the most frequent causes of morbidity and mortality in the course of liver cirrhosis. Several treatments are used for upper gastrointestinal bleeding in people with liver diseases. One of them is vitamin K administration, but it is not known whether it benefits or harms people with acute or chronic liver disease and upper gastrointestinal bleeding. This is an update of this Cochrane review. To assess the beneficial and harmful effects of vitamin K for people with acute or chronic liver disease and upper gastrointestinal bleeding. We searched The Cochrane Hepato-Biliary Controlled Trials Register (February 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2 of 12, 2015), MEDLINE (Ovid SP) (1946 to February 2015), EMBASE (Ovid SP) (1974 to February 2015), Science Citation Index EXPANDED (1900 to February 2015), and LILACS (1982 to 25 February 2015). We sought additional randomised trials from two registries of clinical trials: the World Health Organization Clinical Trials Search Portal and the metaRegister of Controlled Trials. We looked through the reference lists of the retrieved publications and review articles. Randomised clinical trials irrespective of blinding, language, or publication status for assessment of benefits and harms. We considered observational studies for assessment of harms only. \\We aimed to summarise data from randomised clinical trials using Standard Cochrane methodology and assess them according to the GRADE approach. We found no randomised trials on vitamin K for upper gastrointestinal bleeding in people with liver diseases assessing benefits and harms of the intervention. We identified no quasi-randomised studies, historically controlled studies, or observational studies assessing harms. This updated review found no randomised clinical trials of vitamin K for upper gastrointestinal bleeding in people with liver diseases. The benefits and harms of vitamin K need to be tested

Aging contributes to inflammation in upper extremity tendons and declines in forelimb agility in a rat model of upper extremity overuse.

Directory of Open Access Journals (Sweden)

David M Kietrys

Full Text Available We sought to determine if tendon inflammatory and histopathological responses increase in aged rats compared to young rats performing a voluntary upper extremity repetitive task, and if these changes are associated with motor declines. Ninety-six female Sprague-Dawley rats were used in the rat model of upper extremity overuse: 67 aged and 29 young adult rats. After a training period of 4 weeks, task rats performed a voluntary high repetition low force (HRLF handle-pulling task for 2 hrs/day, 3 days/wk for up to 12 weeks. Upper extremity motor function was assessed, as were inflammatory and histomorphological changes in flexor digitorum and supraspinatus tendons. The percentage of successful reaches improved in young adult HRLF rats, but not in aged HRLF rats. Forelimb agility decreased transiently in young adult HRLF rats, but persistently in aged HRLF rats. HRLF task performance for 12 weeks lead to increased IL-1beta and IL-6 in flexor digitorum tendons of aged HRLF rats, compared to aged normal control (NC as well as young adult HRLF rats. In contrast, TNF-alpha increased more in flexor digitorum tendons of young adult 12-week HRLF rats than in aged HRLF rats. Vascularity and collagen fibril organization were not affected by task performance in flexor digitorum tendons of either age group, although cellularity increased in both. By week 12 of HRLF task performance, vascularity and cellularity increased in the supraspinatus tendons of only aged rats. The increased cellularity was due to increased macrophages and connective tissue growth factor (CTGF-immunoreactive fibroblasts in the peritendon. In conclusion, aged rat tendons were overall more affected by the HRLF task than young adult tendons, particularly supraspinatus tendons. Greater inflammatory changes in aged HRLF rat tendons were observed, increases associated temporally with decreased forelimb agility and lack of improvement in task success.

A Rare Cause of Massive Upper Gastrointestinal Hemorrhage in Immunocompromised Host.

Science.gov (United States)

Abdullah, Obai; Pele, Nicole A; Fu, Yumei; Ashraf, Imran; Arif, Murtaza; Bechtold, Matthew L; Grewal, Ajitinder; Hammad, Hazem T

2012-02-01

Mucormycosis is an invasive and aggressive opportunistic fungal infection that usually presents with rhinocerebral or pulmonary involvement and rarely involves the gastrointestinal tract. The disease is acute with mortality rate up to 100%. A 68-year-old male was undergoing treatment at a local hospital for COPD exacerbation with IV steroids and antibiotics. Two weeks into his treatment he suddenly developed massive upper GI bleeding and hemodynamic instability that necessitated transfer to our tertiary care hospital for further treatment and management. An urgent upper endoscopy revealed multiple large and deep gastric and duodenal bulb ulcers with stigmata of recent bleeding. The ulcers were treated endoscopically. Biopsies showed fibrinopurulent debris with fungal organisms. Stains highlighted slightly irregular hyphae with rare septa and yeast suspicious for Candida. The patient was subsequently placed on fluconazole. Unfortunately, the patient's general condition continued to worsen and he developed multiorgan failure and died. Autopsy revealed disseminated systemic mucormycosis. Most of the cases of gastrointestinal mucormycosis were reported from the tropics and few were reported in the United States. The disease occurs most frequently in immunocompromised individuals. The rare incidence of GI involvement, acute nature, severity and the problematic identification of the organisms on biopsies make antemortem diagnosis challenging. Treatment includes parenteral antifungals and debridement of the infected tissues. Gastroenterologists should be aware of this rare cause of gastrointestinal bleeding and understand the importance of communication with the reviewing pathologist so that appropriate, and often lifesaving, therapies can be administered in a timely manner.

Upper bounds of deformation in the Upper Rhine Graben from GPS data - First results from GURN (GNSS Upper Rhine Graben Network)

Science.gov (United States)

Masson, Frederic; Knoepfler, Andreas; Mayer, Michael; Ulrich, Patrice; Heck, Bernhard

2010-05-01

In September 2008, the Institut de Physique du Globe de Strasbourg (Ecole et Observatoire des Sciences de la Terre, EOST) and the Geodetic Institute (GIK) of Karlsruhe University (TH) established a transnational cooperation called GURN (GNSS Upper Rhine Graben Network). Within the GURN initiative these institutions are cooperating in order to establish a highly precise and highly sensitive network of permanently operating GNSS sites for the detection of crustal movements in the Upper Rhine Graben region. At the beginning, the network consisted of the permanently operating GNSS sites of SAPOS®-Baden-Württemberg, different data providers in France (e.g. EOST, Teria, RGP) and some further sites (e.g. IGS). In July 2009, the network was extended to the South when swisstopo (Switzerland) and to the North when SAPOS®-Rheinland-Pfalz joined GURN. Therefore, actually the GNSS network consists of approx. 80 permanently operating reference sites. The presentation will discuss the actual status of GURN, main research goals, and will present first results concerning the data quality as well as time series of a first reprocessing of all available data since 2002 using GAMIT/GLOBK (EOST working group) and the Bernese GPS Software (GIK working group). Based on these time series, the velocity as well as strain fields will be calculated in the future. The GURN initiative is also aiming for the estimation of the upper bounds of deformation in the Upper Rhine Graben region.

Concurrent Preoperative Presence of Hydronephrosis and Flank Pain Independently Predicts Worse Outcome of Upper Tract Urothelial Carcinoma.

Science.gov (United States)

Yeh, Hsin-Chih; Jan, Hau-Chern; Wu, Wen-Jeng; Li, Ching-Chia; Li, Wei-Ming; Ke, Hung-Lung; Huang, Shu-Pin; Liu, Chia-Chu; Lee, Yung-Chin; Yang, Sheau-Fang; Liang, Peir-In; Huang, Chun-Nung

2015-01-01

To investigate the impact of preoperative hydronephrosis and flank pain on prognosis of patients with upper tract urothelial carcinoma. In total, 472 patients with upper tract urothelial carcinoma managed by radical nephroureterectomy were included from Kaohsiung Medical University Hospital Healthcare System. Clinicopathological data were collected retrospectively for analysis. The significance of hydronephrosis, especially when combined with flank pain, and other relevant factors on overall and cancer-specific survival were evaluated. Of the 472 patients, 292 (62%) had preoperative hydronephrosis and 121 (26%) presented with flank pain. Preoperative hydronephrosis was significantly associated with age, hematuria, flank pain, tumor location, and pathological tumor stage. Concurrent presence of hydronephrosis and flank pain was a significant predictor of non-organ-confined disease (multivariate-adjusted hazard ratio = 2.10, P = 0.025). Kaplan-Meier analysis showed significantly poorer overall and cancer-specific survival in patients with preoperative hydronephrosis (P = 0.005 and P = 0.026, respectively) and in patients with flank pain (P hydronephrosis and flank pain independently predicted adverse outcome (hazard ratio = 1.98, P = 0.016 for overall survival and hazard ratio = 1.87, P = 0.036 for and cancer-specific survival, respectively) in multivariate Cox proportional hazards models. In addition, concurrent presence of hydronephrosis and flank pain was also significantly predictive of worse survival in patient with high grade or muscle-invasive disease. Notably, there was no difference in survival between patients with hydronephrosis but devoid of flank pain and those without hydronephrosis. Concurrent preoperative presence of hydronephrosis and flank pain predicted non-organ-confined status of upper tract urothelial carcinoma. When accompanied with flank pain, hydronephrosis represented an independent predictor for worse outcome in patients with upper tract

A Silurian-early Devonian slab window in the southern Central Asian Orogenic Belt: Evidence from high-Mg diorites, adakites and granitoids in the western Central Beishan region, NW China

Science.gov (United States)

Zheng, Rongguo; Xiao, Wenjiao; Li, Jinyi; Wu, Tairan; Zhang, Wen

2018-03-01

The Beishan orogenic belt is a key region for deciphering the accretionary processes of the southern Central Asian Orogenic Belt. Here in this paper we present new zircon U-Pb ages, bulk-rock major and trace element, and zircon Hf isotopic data for the Baitoushan, and Bagelengtai plutons in the western Central Beishan region to address the accretionary processes. The Baitoushan pluton consists of quartz diorites, monzonites and K-feldspar granites, with zircon LA-ICP-MS U-Pb ages of 435 Ma, 421 Ma and 401 Ma, respectively. The Baitoushan quartz diorites and quartz monzonites exhibit relatively high MgO contents and Mg# values (63-72), display enrichments in LILEs and LREEs, and exhibit high Ba (585-1415 ppm), Sr (416-570 ppm) and compatible element (such as Cr and Ni) abundances, which make them akin to typical high-Mg andesites. The Baitoushan quartz diorites and quartz monzonites were probably generated by the interaction of subducted oceanic sediment-derived melts and mantle peridotites. The Baitoushan K-feldspar granites are ascribed to fractionated I-type granites with peraluminous and high-K calc-alkaline characteristics. They exhibit positive εHf(t) values (2.43-7.63) and Mesoproterozoic-Neoproterozoic zircon Hf model ages (0.92-1.60 Ga). Those early Devonian granites, including Baitoushan K-feldspar granite and Gongpoquan leucogranites (402 Ma), are derived from melting of the mafic lower crust and/or sediments by upwelling of hot asthenospheric mantle. The Bagelengtai granodiorites exhibit similar geochemical signatures with that of typical adakites, with a zircon SHRIMP U-Pb age of 435 Ma. They exhibit relatively high Sr (502-628 ppm) and Al2O3 (16.40-17.40 wt.%) contents, and low MgO (1.02-1.29 wt.%), Y (3.37-6.94 ppm) and HREEs contents, with relatively high Sr/Y and (La/Yb)N ratios. The Bagelengtai granodiorites were derived from partial melting of subducted young oceanic crust, with significant contributions of subducted sediments, subsequently

What is the appropriate upper limit for added sugars consumption?

Science.gov (United States)

Rippe, James M; Sievenpiper, John L; Lê, Kim-Anne; White, John S; Clemens, Roger; Angelopoulos, Theodore J

2017-01-01

Dramatic increases in obesity and diabetes have occurred worldwide over the past 30 years. Some investigators have suggested that these increases may be due, in part, to increased added sugars consumption. Several scientific organizations, including the World Health Organization, the Scientific Advisory Council on Nutrition, the Dietary Guidelines Advisory Committee 2015, and the American Heart Association, have recommended significant restrictions on upper limits of sugars consumption. In this review, the scientific evidence related to sugars consumption and its putative link to various chronic conditions such as obesity, diabetes, heart disease, nonalcoholic fatty liver disease, and the metabolic syndrome is examined. While it appears prudent to avoid excessive calories from sugars, the scientific basis for restrictive guidelines is far from settled. © The Author(s) 2016. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Upper Atmosphere Research Satellite (UARS) science data processing center implementation history

Science.gov (United States)

Herring, Ellen L.; Taylor, K. David

1990-01-01

NASA-Goddard is responsible for the development of a ground system for the Upper Atmosphere Research Satellite (UARS) observatory, whose launch is scheduled for 1991. This ground system encompasses a dedicated Central Data Handling Facility (CDHF); attention is presently given to the management of software systems design and implementation phases for CDHF by the UARS organization. Also noted are integration and testing activities performed following software deliveries to the CDHF. The UARS project has an obvious requirement for a powerful and flexible data base management system; an off-the-shelf commercial system has been incorporated.

Upper bounds on superpartner masses from upper bounds on the Higgs boson mass.

Science.gov (United States)

Cabrera, M E; Casas, J A; Delgado, A

2012-01-13

The LHC is putting bounds on the Higgs boson mass. In this Letter we use those bounds to constrain the minimal supersymmetric standard model (MSSM) parameter space using the fact that, in supersymmetry, the Higgs mass is a function of the masses of sparticles, and therefore an upper bound on the Higgs mass translates into an upper bound for the masses for superpartners. We show that, although current bounds do not constrain the MSSM parameter space from above, once the Higgs mass bound improves big regions of this parameter space will be excluded, putting upper bounds on supersymmetry (SUSY) masses. On the other hand, for the case of split-SUSY we show that, for moderate or large tanβ, the present bounds on the Higgs mass imply that the common mass for scalars cannot be greater than 10(11)  GeV. We show how these bounds will evolve as LHC continues to improve the limits on the Higgs mass.

Upper atmosphere research at INPE

International Nuclear Information System (INIS)

Clemesha, B.R.

1984-01-01

Upper atmosphere research at INPE is mainly concerned with the chemistry and dynamics of the stratosphere, upper mesosphere and lower thermosphere, and the middle thermosphere. Experimental work includes lidar observations of the stratospheric aerosol, measurements of stratospheric ozone by Dobson spectrophotometers and by balloon and rocket-borne sondes, lidar measurements of atmospheric sodium, and photometric observations of O, O 2 , OH and Na emissions, including interferrometric measurements of the OI6300 emission for the purpose of determing thermospheric winds and temperature. The airglow observations also include measurements of a number of emissions produced by the precipitation of energetic neutral particles generated by charge exchange in the ring current. Some recent results of INPE's upper atmosphere program are presented. (Author) [pt

Abdominal multi-organ CT segmentation using organ correlation graph and prediction-based shape and location priors.

Science.gov (United States)

Okada, Toshiyuki; Linguraru, Marius George; Hori, Masatoshi; Summers, Ronald M; Tomiyama, Noriyuki; Sato, Yoshinobu

2013-01-01

The paper addresses the automated segmentation of multiple organs in upper abdominal CT data. We propose a framework of multi-organ segmentation which is adaptable to any imaging conditions without using intensity information in manually traced training data. The features of the framework are as follows: (1) the organ correlation graph (OCG) is introduced, which encodes the spatial correlations among organs inherent in human anatomy; (2) the patient-specific organ shape and location priors obtained using OCG enable the estimation of intensity priors from only target data and optionally a number of untraced CT data of the same imaging condition as the target data. The proposed methods were evaluated through segmentation of eight abdominal organs (liver, spleen, left and right kidney, pancreas, gallbladder, aorta, and inferior vena cava) from 86 CT data obtained by four imaging conditions at two hospitals. The performance was comparable to the state-of-the-art method using intensity priors constructed from manually traced data.

Upper atmosphere research satellite program. [to study the chemistry energetics, and dynamics

Science.gov (United States)

Huntress, W. T., Jr.

1978-01-01

A satellite program to conduct research on the chemistry, energetics, and dynamics of the upper atmosphere was developed. The scientific goals of the Upper Atmospheric Research Program, the program requirements, and the approach toward meeting those requirements are outlined. An initial series of two overlapping spacecraft missions is described. Both spacecraft are launched and recovered by the STS, one in the winter of 1983 at a 56 deg inclination, and the other a year later at a 70 deg inclination. The duration of each mission is 18 months, and each carries instruments to make global measurements of the temperature, winds, composition, irradation, and radiance in the stratosphere, mesosphere, and lower thermosphere between the tropopause and 120 km altitude. The program requires a dedicated ground-based data system and a science team organization that leads to a strong interaction between the experiments and theory. The program includes supportive observations from other platforms such as rockets, balloons, and the Spacelab.

The Svalbard Caledonides - a collage of Laurentian, Timanian and exotic terranes assembled by Silurian - Late (?) Devonian transcurrent faulting.

Science.gov (United States)

Andresen, Arild; Gasser, Deta

2014-05-01

New field and geochronological data from NE Greenland and Svalbard indicate that most of the sub-terranes making up the Svalbard Caledonides (Eastern, Northwestern and Southwestern Terranes) are derived from Laurentias eastern margin. The Neoproterozoic deposits of the Eastern Terrane (Nordaustlandet) show an almost one to one correlation with the Late Neoproterozoic Eleonore Bay Supergroup in NE Greenland. Great similarities also exist between the substratum to the Neoproterozoic deposits in the two areas. The "Barentsian plate/continent" is interpreted to be derived from Laurentias eastern margin Lithologic similarities also exist between parts of the Northwestern Terrane and NE Greenland. The geologic evolution of Svalbard`s Southwestern Terrane, with subduction complexes and Late Neoproterozoic intrusives (Timanian ?) is poorly understood. It will, however, be argued that there is no need to invoke considerable right lateral strike-slip movement of the Motalefjellet subduction complex and related rocks from a position in Arctic Canada to their present position within the Southwestern Terrane, as proposed by some authors. The structural grain of the Svalbard Caledonides, oblique to East Greenland and Scandinavian Caledonides, as well as the Ellesmerian Orogen, is interpreted to be due to counter-clockwise rotation (c. 45o) of the Caledonian trend. A counter-clockwise rotation is to be expected when the northward moving terranes reached the E-W trending Franklinian Basin north of Greenland/Laurentia, which in Early Devonian time had not yet started to close. The model predicts that there should be a dramatic change in the Caledonian structural grain somewhere south of Bjørnøya. It is furthermore speculated that the fan-shaped orientation of Late Paleozoic rift basins in the Western Barents Sea is controlled by reactivation of the rotated structural trend (e.g. Billefjorden Fault Zone and Billefjorden Trough).

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

Gram stain microbiological pattern of upper extremities suppuration at Baptist Medical Centre, Ogbomoso Nigeria: a fifteen month review.

Science.gov (United States)

Oke, A J; Olaolorun, D A; Meier, D E; Tarpley, J L

2011-06-01

Sixty-eight (68) patients with serious upper extremity suppurative infections, presenting within a period of fifteen (15) months, were prospectively studied clinically, Gram stain of aspirates/pus were performed, specimen cultured, planted, and where indicated glucose levels and haemoglobin genotype determined. Half of the patients had hand infections. Staphylococcus aureus was isolated from thirty-nine (39) patients. Gram Negative bacilli, including Salmonella were more isolated from patients with diabetes mellitus or Hgb SS or SC. The Gram stain results correlated with the culture result 90%. When Gram Positive cocci were demonstrated in the primary microscopic examination, cultures were not mandatory. When no organism was demonstrated on primary Gram stain or the patient was diabetic or a sickler, cultures of the specimens were done. The Gram stain, well performed, remains a useful, inexpensive, technologically appropriate laboratory test for abetting decision making in patients with upper extremity suppurative infections. Organisms encountered in this study included: Staphylococcus aureus, Streptococcus pyogenes, Salmonella typhi, Proteus mirabilis, Pseudomonas aeruginosa, and Coliforms.

Retrowedge-related Carboniferous units and coeval magmatism in the northwestern Neuquén province, Argentina

Science.gov (United States)

Zappettini, Eduardo O.; Chernicoff, Carlos J.; Santos, Joao O. S.; Dalponte, Marcelo; Belousova, Elena; McNaughton, Neal

2012-11-01

The studied Carboniferous units comprise metasedimentary (Guaraco Norte Formation), pyroclastic (Arroyo del Torreón Formation), and sedimentary (Huaraco Formation) rocks that crop out in the northwestern Neuquén province, Argentina. They form part of the basement of the Neuquén Basin and are mostly coeval with the Late Paleozoic accretionary prism complex of the Coastal Cordillera, south-central Chile. U-Pb SHRIMP dating of detrital zircon yielded a maximum depositional age of 374 Ma (Upper Devonian) for the Guaraco Norte Formation and 389 Ma for the Arroyo del Torreón Formation. Detrital magmatic zircon from the Guaraco Norte Formation are grouped into two main populations of Devonian and Ordovician (Famatinian) ages. In the Arroyo del Torreón Formation, zircon populations are also of Devonian and Ordovician (Famatinian), as well as of Late Neoproterozoic and Mesoproterozoic ages. In both units, there is a conspicuous population of Devonian magmatic zircon grains (from 406 ± 4 Ma to 369 ± 5 Ma), indicative of active magmatism at that time range. The ɛHf values of this population range between -2.84 and -0.7, and the TDM-(Hf) are mostly Mesoproterozoic, suggesting that the primary sources of the Devonian magmatism contained small amounts of Mesoproterozoic recycled crustal components. The chemical composition of the Guaraco Norte Formation corresponds to recycled, mature polycyclic sediment of mature continental provenance, pointing to a passive margin with minor inputs from continental margin magmatic rocks. The chemical signature of the Huaraco Formation indicates that a magmatic arc was the main provenance for sediments of this unit, which is consistent with the occurrence of tuff—mostly in the Arroyo del Torreón Formation and very scarcely in the Huaraco Formation—with a volcanic-arc signature, jointly indicating the occurrence of a Carboniferous active arc magmatism during the deposition of the two units. The Guaraco Norte Formation is interpreted

Portable upper extremity robotics is as efficacious as upper extremity rehabilitative therapy: a randomized controlled pilot trial.

Science.gov (United States)

Page, Stephen J; Hill, Valerie; White, Susan

2013-06-01

To compare the efficacy of a repetitive task-specific practice regimen integrating a portable, electromyography-controlled brace called the 'Myomo' versus usual care repetitive task-specific practice in subjects with chronic, moderate upper extremity impairment. Sixteen subjects (7 males; mean age 57.0 ± 11.02 years; mean time post stroke 75.0 ± 87.63 months; 5 left-sided strokes) exhibiting chronic, stable, moderate upper extremity impairment. Subjects were administered repetitive task-specific practice in which they participated in valued, functional tasks using their paretic upper extremities. Both groups were supervised by a therapist and were administered therapy targeting their paretic upper extremities that was 30 minutes in duration, occurring 3 days/week for eight weeks. One group participated in repetitive task-specific practice entirely while wearing the portable robotic, while the other performed the same activity regimen manually. The upper extremity Fugl-Meyer, Canadian Occupational Performance Measure and Stroke Impact Scale were administered on two occasions before intervention and once after intervention. After intervention, groups exhibited nearly identical Fugl-Meyer score increases of ≈2.1 points; the group using robotics exhibited larger score changes on all but one of the Canadian Occupational Performance Measure and Stroke Impact Scale subscales, including a 12.5-point increase on the Stroke Impact Scale recovery subscale. Findings suggest that therapist-supervised repetitive task-specific practice integrating robotics is as efficacious as manual practice in subjects with moderate upper extremity impairment.

Hydrogeology of the Owego-Apalachin Elementary School Geothermal Fields, Tioga County, New York

Science.gov (United States)

Williams, John H.; Kappel, William M.

2015-12-22

The hydrogeology of the Owego-Apalachin Elementary School geothermal fields, which penetrate saline water and methane in fractured upper Devonian age bedrock in the Owego Creek valley, south-central New York, was characterized through the analysis of drilling and geophysical logs, water-level monitoring data, and specific-depth water samples. Hydrogeologic insights gained during the study proved beneficial for the design of the geothermal drilling program and protection of the overlying aquifer during construction, and may be useful for the development of future geothermal fields and other energy-related activities, such as drilling for oil and natural gas in similar fractured-bedrock settings.

A Boundary Property for Upper Domination

KAUST Repository

AbouEisha, Hassan M.; Hussain, Shahid; Lozin, Vadim; Monnot, Jé rô me; Ries, Bernard; Zamaraev, Viktor

2016-01-01

An upper dominating set in a graph is a minimal (with respect to set inclusion) dominating set of maximum cardinality.The problem of finding an upper dominating set is generally NP-hard, but can be solved in polynomial time in some restricted graph

Organ harvesting from anencephalic infants: health management over a sinkhole.

Science.gov (United States)

Alatis, A J

As technology increases in the field of organ transplantation for newborns, a problematic limitation persists: too few organ donors are available to match the number of needy organ donees. Anencephalic newborns have been suggested (and recently used) as organ sources. Anencephalic infants are born without the upper part of their brain and usually die within a week after birth. This article will address the ethical considerations of using these infants as organ sources, particularly from the view of a physician and an attorney. This piece will further analyze the medico-legal ramifications of the various legislative proposals addressing this subject.

Upper tropospheric cloud systems determined from IR Sounders and their influence on the atmosphere

Science.gov (United States)

Stubenrauch, Claudia; Protopapadaki, Sofia; Feofilov, Artem; Velasco, Carola Barrientos

2017-02-01

Covering about 30% of the Earth, upper tropospheric clouds play a key role in the climate system by modulating the Earth's energy budget and heat transport. Infrared Sounders reliably identify cirrus down to an IR optical depth of 0.1. Recently LMD has built global cloud climate data records from AIRS and IASI observations, covering the periods from 2003-2015 and 2008-2015, respectively. Upper tropospheric clouds often form mesoscale systems. Their organization and properties are being studied by (1) distinguishing cloud regimes within 2° × 2° regions and (2) applying a spatial composite technique on adjacent cloud pressures, which estimates the horizontal extent of the mesoscale cloud systems. Convective core, cirrus anvil and thin cirrus of these systems are then distinguished by their emissivity. Compared to other studies of tropical mesoscale convective systems our data include also the thinner anvil parts, which make out about 30% of the area of tropical mesoscale convective systems. Once the horizontal and vertical structure of these upper tropospheric cloud systems is known, we can estimate their radiative effects in terms of top of atmosphere and surface radiative fluxes and by computing their heating rates.

Characterisation of an extremely organic sulfur-rich, 150 Ma old carbonaceous rock: Palaeoenvironmental implications

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Kaam-Peters, H.M.E. van

1997-01-01

An extremely organic sulphur-rich coccolithic limestone of the Upper Jurassic Calcaires en plaquettes Formation (southern Jura, France) was analysed for its molecular composition using chemical and instrumental methods. The bitumen accounts for 19% of the total organic carbon, and consists

Temperature influences on growth of aquatic organisms

International Nuclear Information System (INIS)

Coutant, C.C.; Suffern, J.S.

1977-01-01

Temperature profoundly affects the growth rates of aquatic organisms, and its control is essential for effective aquaculture. Characteristically, both low and high temperatures produce slow growth rates and inefficient food conversion, while intermediate temperature ranges provide rapid growth and efficient food conversion. Distinct, species-specific optimum temperatures and upper and lower temperatures of zero growth can often be defined. Thermal effects can be greatly modified by amounts and quality of food. These data not only provide the basis for criteria which maintain growth of wild organisms but also for effectively using waste heat to create optimal conditions of temperature and food ration for growing aquatic organisms commercially

The Upper Atmosphere; Threshold of Space.

Science.gov (United States)

Bird, John

This booklet contains illustrations of the upper atmosphere, describes some recent discoveries, and suggests future research questions. It contains many color photographs. Sections include: (1) "Where Does Space Begin?"; (2) "Importance of the Upper Atmosphere" (including neutral atmosphere, ionized regions, and balloon and investigations); (3)…

Fossil record of stem groups employed in evaluating the chronogram of insects (Arthropoda: Hexapoda)

Science.gov (United States)

Wang, Yan-hui; Engel, Michael S.; Rafael, José A.; Wu, Hao-yang; Rédei, Dávid; Xie, Qiang; Wang, Gang; Liu, Xiao-guang; Bu, Wen-jun

2016-01-01

Insecta s. str. (=Ectognatha), comprise the largest and most diversified group of living organisms, accounting for roughly half of the biodiversity on Earth. Understanding insect relationships and the specific time intervals for their episodes of radiation and extinction are critical to any comprehensive perspective on evolutionary events. Although some deeper nodes have been resolved congruently, the complete evolution of insects has remained obscure due to the lack of direct fossil evidence. Besides, various evolutionary phases of insects and the corresponding driving forces of diversification remain to be recognized. In this study, a comprehensive sample of all insect orders was used to reconstruct their phylogenetic relationships and estimate deep divergences. The phylogenetic relationships of insect orders were congruently recovered by Bayesian inference and maximum likelihood analyses. A complete timescale of divergences based on an uncorrelated log-normal relaxed clock model was established among all lineages of winged insects. The inferred timescale for various nodes are congruent with major historical events including the increase of atmospheric oxygen in the Late Silurian and earliest Devonian, the radiation of vascular plants in the Devonian, and with the available fossil record of the stem groups to various insect lineages in the Devonian and Carboniferous. PMID:27958352

Upper cervical and upper thoracic thrust manipulation versus nonthrust mobilization in patients with mechanical neck pain: a multicenter randomized clinical trial.

Science.gov (United States)

Dunning, James R; Cleland, Joshua A; Waldrop, Mark A; Arnot, Cathy F; Young, Ian A; Turner, Michael; Sigurdsson, Gisli

2012-01-01

Randomized clinical trial. To compare the short-term effects of upper cervical and upper thoracic high-velocity low-amplitude (HVLA) thrust manipulation to nonthrust mobilization in patients with neck pain. Although upper cervical and upper thoracic HVLA thrust manipulation and nonthrust mobilization are common interventions for the management of neck pain, no studies have directly compared the effects of both upper cervical and upper thoracic HVLA thrust manipulation to nonthrust mobilization in patients with neck pain. Patients completed the Neck Disability Index, the numeric pain rating scale, the flexion-rotation test for measurement of C1-2 passive rotation range of motion, and the craniocervical flexion test for measurement of deep cervical flexor motor performance. Following the baseline evaluation, patients were randomized to receive either HVLA thrust manipulation or nonthrust mobilization to the upper cervical (C1-2) and upper thoracic (T1-2) spines. Patients were reexamined 48-hours after the initial examination and again completed the outcome measures. The effects of treatment on disability, pain, C1-2 passive rotation range of motion, and motor performance of the deep cervical flexors were examined with a 2-by-2 mixed-model analysis of variance (ANOVA). One hundred seven patients satisfied the eligibility criteria, agreed to participate, and were randomized into the HVLA thrust manipulation (n = 56) and nonthrust mobilization (n = 51) groups. The 2-by-2 ANOVA demonstrated that patients with mechanical neck pain who received the combination of upper cervical and upper thoracic HVLA thrust manipulation experienced significantly (Ppain (58.5%) than those of the nonthrust mobilization group (12.8% and 12.6%, respectively) following treatment. In addition, the HVLA thrust manipulation group had significantly (Pcervical flexor muscles as compared to the group that received nonthrust mobilization. The number needed to treat to avoid an unsuccessful outcome

Regional diagenesis of sandstone in the Upper Jurassic Morrison Formation, San Juan Basin, New Mexico and Colorado

International Nuclear Information System (INIS)

Hansley, P.L.

1990-01-01

The author reports that early authigenic mineral assemblages and vitroclastic textures are very well preserved in upper sandstones of the Upper Jurassic Morrison Formation. The distributions of the authigenic minerals were controlled, in part, by chemical gradients in a large saline, alkaline lake (Lake T'oo'dichi) that existed in late Morrison time. Sandstones on lake margins were cemented by smectite and silica, whereas sandstones nearer the lake center, in which waters were most saline and alkaline, were cemented by zeolites. Diagenetic alterations in sandstones were promoted by alkaline interstitial waters that emanated from adjacent fine-grained, tuffaceous lake beds. Metastable phases that precipitated first were replaced relatively quickly by more stable, ordered phases in the geochemically favorable environment of the closed basin setting. Elevation of temperatures above the geothermal gradient was proved by the influx of warm, deep-basin waters that locally modified early diagenetic assemblages during burial diagenesis. In organic- (and commonly also uranium ore-) bearing sandstones located primarily in the southern part of the basin, complex diagenetic assemblages resulted from water/rock reactions involving soluble organic complexes

Diagnosis and treatment of upper limb apraxia

OpenAIRE

Dovern, A.; Fink, G. R.; Weiss, P. H.

2012-01-01

Upper limb apraxia, a disorder of higher motor cognition, is a common consequence of left-hemispheric stroke. Contrary to common assumption, apraxic deficits not only manifest themselves during clinical testing but also have delirious effects on the patients’ everyday life and rehabilitation. Thus, a reliable diagnosis and efficient treatment of upper limb apraxia is important to improve the patients’ prognosis after stroke. Nevertheless, to date, upper limb apraxia is still an underdiagnosed...

Hydrology, Water Quality, and Surface- and Ground-Water Interactions in the Upper Hillsborough River Watershed, West-Central Florida

Science.gov (United States)

Trommer, J.T.; Sacks, L.A.; Kuniansky, E.L.

2007-01-01

fertilizer or animal waste. Wells at the Blackwater Creek and Hillsborough River at State Road 39 transects showed little seasonal variation in dissolved organic carbon. Dissolved organic carbon concentrations, however, were greater during the wet season than during the dry season at the Hillsborough River Tract transect, indicating some influence from surface-water sources. During dry periods, streamflow in the upper Hillsborough River was sustained by ground water from the underlying Upper Floridan aquifer. During wet periods, streamflow had additional contributions from runoff, and release of water from extensive riverine wetlands, and by overflow from the Withlacoochee River. In contrast, streamflow in Blackwater and Itchepackesassa Creeks was less constant, with many no-flow days occurring during dry periods. During wet season storm events, streamflow peaks occur more rapidly because there is greater confinement between the surficial deposits and the Upper Floridan aquifer, and these creeks have been highly channelized, leaving less of the adjacent wetlands intact. During dry periods, Blackwater Creek is dry upstream from its confluence with Itchepackesassa Creek, and all downstream flow is from Itchepackesassa Creek. Much of the dry season flow in Itchepackesassa Creek originates from a treated wastewater effluent outfall located on East Canal. Long-term streamflow at the Hillsborough River and Blackwater Creek stations was greater than the discharge observed during the study period. Water quality in the upper Hillsborough River is influenced by ground-water discharge. The chemical composition of water from Blackwater Creek, Itchepackesassa Creek, and East Canal was more variable because there was less ground-water discharge to these creeks than to the upper Hillsborough River, and because of the influence of wastewater effluent. Strontium isotope data indicated that the source of the water at all Hillsborough River sites during the dry season was the Oli

Fossil micro-organisms evidenced by electronic microscopy

Energy Technology Data Exchange (ETDEWEB)

Prashnowsky, A.A.; Oberlies, F.; Burger, K.

1983-04-01

Fossil microorganisms in colonies and in the form of isolated cells (iron bacteria, fungi, actinomycetes etc.) were detected by electron microscopy of rocks containing remains of plant roots, carbonaceous substance, and strata of clay iron stone with ooids. These findings suggest an environment favourable to bacterial activity during sedimentation in the Upper Carboniferous and during the later processes of peat and coal formation. They also suggest that bacterial processes are an important factor in coal formation. Accurate data on coal formation can only be obtained by systematic biochemical studies. Analyses of the defined organic substances provide a better understanding of the conversion processes of the original substances. For example, the results of sterine analysis provide information on the mycoplancton, phytoplancton and zooplancton of the Upper Carboniferous. For some types of rock, the ratio of saponifiable to non-saponifiable constituents of the organic compounds yield information on stability under various geochemical conditions. The interactions between the various groups of microorganisms also play a major role in the solution of ecological problems.

A new psammosteid (Agnatha, Heterostraci from the Amata Regional Stage of the Main Devonian Field and morpho-histological types of discrete micromeric elements in the family Psammosteidae

Directory of Open Access Journals (Sweden)

Vadim N. Glinskiy

2017-05-01

Full Text Available In memory of an outstanding palaeoichthyologist Elga Mark-Kurik The range of diversity of psammosteids from the family Psammosteidae is still poorly known. Here a new species, Psammosteus ramosus sp. nov. Glinskiy, from the Amata Regional Stage of the Main Devonian Field is described. Its morphology, ornamentation, histology of exoskeletal plates, and micromeric elements are compared with those of other representatives of the family Psammosteidae. The comparison shows a close relationship of the new species with Psammosteus falcatus Obruchev, P. kiaeri Halstead Tarlo and P. pectinatus Obruchev, a group of species that is significantly different from other representatives of the genus Psammosteus and constitutes a separate evolutionary lineage. On the basis of morphological and histological features we here differentiate in the fields of tesserae of Psammosteidae the discrete micromeric elements of the ‘basic type’, known in Psammosteus bergi (Obruchev, P. levis Obruchev, P. livonicus Obruchev, P. maeandrinus Agassiz, P. megalopteryx (Trautschold, P. praecursor Obruchev and Karelosteus weberi Obruchev, and micromeric elements of the ‘progressive type’, known in Psammosteus falcatus, P. cf. kiaeri and P. ramosus sp. nov. Glinskiy.

Introducing Undergraduates to Research Using a Suzuki-Miyaura Cross-Coupling Organic Chemistry Miniproject

Science.gov (United States)

Oliveira, Deyvid G. M.; Rosa, Clarissa H.; Vargas, Bruna P.; Rosa, Diego S.; Silveira, Ma´rcia V.; de Moura, Neusa F.; Rosa, Gilber R.

2015-01-01

A five-week miniproject is described for an upper-division experimental organic chemistry course. The activities include synthesis of a phenylboronic acid via a Grignard reaction and its use in a Suzuki-Miyaura cross-coupling reaction. Technical skills and concepts normally presented in practical organic chemistry courses are covered, including…

Organic superconductivity

International Nuclear Information System (INIS)

Jerome, D.

1980-01-01

We present the experimental evidences for the existence of a superconducting state in the Quasi One Dimensional organic conductor (TMTSF) 2 PF 6 . Superconductivity occuring at 1 K under 12 kbar is characterized by a zero resistance diamagnetic state. The anistropy of the upper critical field of this type II superconductor is consistent with the band structure anistropy. We present evidences for the existence of large superconducting precursor effects giving rise to a dominant paraconductive contribution below 40 K. We also discuss the anomalously large pressure dependence of T sb(s), which drops to 0.19 K under 24 kbar in terms of the current theories. (author)

A Boundary Property for Upper Domination

KAUST Repository

AbouEisha, Hassan M.

2016-08-08

An upper dominating set in a graph is a minimal (with respect to set inclusion) dominating set of maximum cardinality.The problem of finding an upper dominating set is generally NP-hard, but can be solved in polynomial time in some restricted graph classes, such as P4-free graphs or 2K2-free graphs.For classes defined by finitely many forbidden induced subgraphs, the boundary separating difficult instances of the problem from polynomially solvable ones consists of the so called boundary classes.However, none of such classes has been identified so far for the upper dominating set problem.In the present paper, we discover the first boundary class for this problem.

47 CFR 90.1408 - Organization and structure of the 700 MHz public/private partnership.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Organization and structure of the 700 MHz public/private partnership. 90.1408 Section 90.1408 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Partnership § 90.1408 Organization and structure of the 700 MHz public/private partnership. (a) The Upper 700...

47 CFR 27.1308 - Organization and structure of the 700 MHz public/private partnership.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Organization and structure of the 700 MHz public/private partnership. 27.1308 Section 27.1308 Telecommunication FEDERAL COMMUNICATIONS COMMISSION... Partnership § 27.1308 Organization and structure of the 700 MHz public/private partnership. (a) The Upper 700...

Geochemical Characterization of the Upper and Middle Floridan Aquifer System, South Florida

Science.gov (United States)

Mirecki, J.; Richardson, E.; Bennett, M.; Hendel, J.

2008-05-01

Our study focus is to characterize the water quality and geochemical environment of the Floridan Aquifer System (FAS) throughout the regional flowpath. A synoptic survey of 21 wells (n=15, upper FAS; n=6 middle FAS) was supplemented by additional samples (n=11) obtained during exploratory well development at 4 aquifer storage recovery (ASR) pilot sites. Synoptic survey samples were analyzed intensively, yielding a dataset that consists of major and trace dissolved constituents (including metals), stable isotopes (δ18O, δ13C, δD, δ34S in sulfate and sulfide), carbon species (carbonate alkalinity and organic carbon), uranium-series radionuclides, nutrients, and selected microbes and pathogens. The objectives of this study are three-fold: 1) to provide baseline water-quality and geochemical information prior to initiation of ASR activities that are part of the Comprehensive Everglades Restoration Plan; 2) to quantify the major controls on geochemical evolution along upper and middle FAS flowpaths using geochemical modeling methods; and 3) to identify areas where water- quality may limit the feasibility of ASR methods in the FAS. Preliminary interpretations water quality changes along the regional FAS flowpath can be summarized as follows. Concentrations of dissolved constituents increase from north to south along the flow path; generally, the upper FAS has lower total dissolved solids than the middle FAS at locations where well pairs were analyzed. The redox environment changes from oxic to strongly anoxic, very close to the recharge area. Redox measurements, dissolved iron, sulfide, and sulfur isotope data are consistent with sulfate-reducing conditions. Uranium-series isotope concentrations and activities generally are below regulatory criteria, with few exceptions in both the upper and middle FAS. Areas with greater radionuclide activity occur primarily at distal flowpath locations or at the coast.

Cycles atmosphériques O2-C02. Evolution, sédimentation et mise en réserve de l'énergie solaire (résumé Atmospheric O2-Co2 Cycles. Evolution, Sedimentation and Solar Energy Storage (Summary

Directory of Open Access Journals (Sweden)

Brunn J. H.

2006-10-01

is proposed, as a line for research and correlations, that cyclic reactions between C02 producing volcanism and 02 producing plants govern some aspects of evolution and sedimentation, in particular that of iron and organic matter coumpounds. Under Archean anoxic atmosphere and slow initial evolution, cycles were limited to the sea, with feed-back oscillations between ferrous iron and oxydising bacteria (Berckner and Marshall, Cloud. Development of blue Algue increased the O content. Insoluble ferric oxydes were retained on the continents (first Red Beds. Metazoa appeared, but being shelless (Ediacara fauna, they indicate that C02 content remained high until Lower Cambrian, when shells appeared. Poorly diversified floras induce ample cycles between Upper Precambrian and Upper Jurassic. Depletion of CO2 (Cambrian, Devonian, Permian favours animals especially Vertebrates development, deposition of Red Beds, limestones, evaporites (nebulosity low, climatic contrasts ; recharge of CO2 through volcanic-orogenic-activity (Ordovician, Dinantian, Upper Trias stimulates plant life, increases nebulosity, reduces climatic contrasts but precipitations develop polar ice caps. Easily achieved reducing conditions enable the accumulation of organic matter (Silurian, Pennsylvanian, Lias. Marine iron deposits occur at transition periods: Lower Ordovician, Lower Devonian, Upper Lias. From Upper Jurassic onwards, increasing complexity of floras reduce the amplitude of atmospheric cycles, but tendancies towards Red Beds, evaporites or organic matter deposits still alternate to some extent.

Organic chemistry on Titan

Science.gov (United States)

Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

1979-01-01

Features taken from various models of Titan's atmosphere are combined in a working composite model that provides environmental constraints within which different pathways for organic chemical synthesis are determined. Experimental results and theoretical modeling suggest that the organic chemistry of the satellite is dominated by two processes: photochemistry and energetic particle bombardment. Photochemical reactions of CH4 in the upper atmosphere can account for the presence of C2 hydrocarbons. Reactions initiated at various levels of the atmosphere by cosmic rays, Saturn 'wind', and solar wind particle bombardment of a CH4-N2 atmospheric mixture can account for the UV-visible absorbing stratospheric haze, the reddish appearance of the satellite, and some of the C2 hydrocarbons. In the lower atmosphere photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. It is concluded that the surface of Titan may contain ancient or recent organic matter (or both) produced in the atmosphere.

The geology of Pedra Verde region, Ceara, Brazil

International Nuclear Information System (INIS)

Korpershoek, H.R.; Mendonca, J.A.C. de; Torquato, J.R.

1979-01-01

The upper Proterozoic Mambira Formation (≥ 1.1000 m.y.) consists of > 1000 m of micaschists with subordinate quartzites and limestones, its upper part, the ''Pedra Verde Phyllite'', is composed of phyelitic slump breccias, with abundance of pyrite. The Mambira formation crops out in the west flank of the tope Anticline, formed by ∼ 600 m of quartzites with sillimanite and/or andalusite (Sao Joaquim Formation), underlain by granitoid gneisses, representing the amphibolite facies. The contact between the Sao Joaquim and Mabira Formations appears to be tectonic. The folding and the metamorphism of the latter date from the Brazilian Cycle, which also affected the gneisses, causing homogeneization of the whole-rock K/Ar ages around 500 m.y. After erosion of some 10.000 m of sedimentary re-activation of the faults, which may already have formed during the deposition of the Mambira Formation resulted in the development of the Ubari Graben. The above formations are unconformably overlain by 300-350 m of subhorizontal Shallow-Marine sandstones belonging to the Serra Grande Formation, of upper silurian to lower devonian ages [pt

Upper gastrointestinal alterations in kidney transplant candidates.

Science.gov (United States)

Homse Netto, João Pedro; Pinheiro, João Pedro Sant'Anna; Ferrari, Mariana Lopes; Soares, Mirella Tizziani; Silveira, Rogério Augusto Gomes; Maioli, Mariana Espiga; Delfino, Vinicius Daher Alvares

2018-05-14

The incidence of gastrointestinal disorders among patients with chronic kidney disease (CKD) is high, despite the lack of a good correlation between endoscopic findings and symptoms. Many services thus perform upper gastrointestinal (UGI) endoscopy on kidney transplant candidates. This study aims to describe the alterations seen on the upper endoscopies of 96 kidney-transplant candidates seen from 2014 to 2015. Ninety-six CKD patients underwent upper endoscopic examination as part of the preparation to receive kidney grafts. The data collected from the patients' medical records were charted on Microsoft Office Excel 2016 and presented descriptively. Mean values, medians, interquartile ranges and 95% confidence intervals of the clinic and epidemiological variables were calculated. Possible associations between endoscopic findings and infection by H. pylori were studied. Males accounted for 54.17% of the 96 patients included in the study. Median age and time on dialysis were 50 years and 50 months, respectively. The most frequent upper endoscopy finding was enanthematous pangastritis (57.30%), followed by erosive esophagitis (30.20%). Gastric intestinal metaplasia and peptic ulcer were found in 8.33% and 7.30% of the patients, respectively. H. pylori tests were positive in 49 patients, and H. pylori infection was correlated only with non-erosive esophagitis (P = 0.046). Abnormal upper endoscopy findings were detected in all studied patients. This study suggested that upper endoscopy is a valid procedure for kidney transplant candidates. However, prospective studies are needed to shed more light on this matter.

Lathlike upper bainite in a silicon steel

International Nuclear Information System (INIS)

Liu Cheng; Zhao Zhenbo; Bhole, S.D.

2006-01-01

The morphology and mechanical properties of upper bainite formed isothermally at 400 deg. C for different holding times in a 1.83 wt.% silicon steel have been investigated by optical metallograph, X-ray diffraction and transmission electron microscopy (TEM). In the early stage of upper bainitic transformation, lathlike bainite whose individual lath ferrite is separated by the thin film type of retained austenite is obtained. As the isothermal holding times are increased, the blocky region consisting of retained austenite and martensite is also found. The stability of retained austenite in lathlike upper bainite is studied in relation to the isothermal treatment times, and the heat treatment conditions. The results show that an optimum combination of strength and ductility is attributed to the formation of bainitic ferrite (BF) and a large amount of thin film carbon-enriched retained austenite in the upper bainite

Embolization for non-variceal upper gastrointestinal tract haemorrhage: A systematic review

Energy Technology Data Exchange (ETDEWEB)

Mirsadraee, S.; Tirukonda, P.; Nicholson, A. [Department of Radiology, Leeds General Infirmary, Leeds (United Kingdom); Everett, S.M. [Department of Gastroenterology, Leeds General Infirmary, Leeds (United Kingdom); McPherson, S.J., E-mail: simon.mcpherson@leedsth.nhs.u [Department of Radiology, Leeds General Infirmary, Leeds (United Kingdom)

2011-06-15

Aim: To assess the published evidence on the endovascular treatment of non-variceal upper gastrointestinal haemorrhage. Materials and methods: An Ovid Medline search of published literature was performed (1966-2009). Non-English literature, experimental studies, variceal haemorrhage and case series with fewer than five patients were excluded. The search yielded 1888 abstracts. Thirty-five articles were selected for final analysis. Results: The total number of pooled patients was 927. The technical and clinical success of embolization ranged from 52-100% and 44-100%, respectively. The pooled mean technical/clinical success rate in primary upper gastrointestinal tract haemorrhage (PUGITH) only, trans-papillary haemorrhage (TPH) only, and mixed studies were 84%/67%, 93%/89%, and 93%/64%, respectively. Clinical outcome was adversely affected by multi-organ failure, shock, corticosteroids, transfusion, and coagulopathy. The anatomical source of haemorrhage and procedural variables did not affect the outcome. A successful embolization improved survival by 13.3 times. Retrospective comparison with surgery demonstrated equivalent mortality and clinical success, despite embolization being applied to a more elderly population with a higher prevalence of co-morbidities. Conclusions: Embolization is effective in this very difficult cohort of patients with outcomes similar to surgery.

Upper gastrointestinal symptoms, psychosocial co-morbidity and health care seeking in general practice: population based case control study

Directory of Open Access Journals (Sweden)

Schellevis François G

2009-09-01

social co-morbidity was strongest associated with patients suffering from upper GI symptoms. Conclusion Patients with upper GI symptoms visit their PCP more frequently for problems of any organ system, including psychosocial problems. The relationship between upper GI symptoms and psychological problems is equivocal and may reflect increased health care demands in general.

Environmental conditions during the Frasnian-Fammenian mass extinction inferred from chlorophyll-derived porphyrin biomarkers.

Science.gov (United States)

Uveges, B. T.; Junium, C. K.; Cohen, P. A.; Boyer, D.

2014-12-01

The widespread mass extinction that occurred across the Frasnian- Fammenian (F-F) boundary was one of the largest losses of biodiversity in Earth's history. The F-F extinction interval is expressed in western New York State by two organic rich black shale intervals known as the Upper and Lower Kellwasser events. These shale intervals are well preserved, thermally immature, and are well constrained in age by conodont biostratigraphy, and thus provide an exceptional opportunity to study the organic material originating from the F-F boundary. In order to test hypotheses about the cause(s) and consequences of the FF biotic crisis, a broader knowledge of the organic carbon sources is needed, and a characterization of the marine primary producer communities will assist in this endeavor. One such avenue is through the study of chlorophyll-derived biomarkers (porphyrins). The organic extracts of powdered shale samples from the Kellwasser horizons were analyzed using HPLC/LC-MSn and diode array UV-Vis spectroscopy. Preliminary data from the Kellwasser intervals reveal only one porphyrin, with a mass (M+H) of 600. The UV-Vis absorbance spectrum (Soret = 405nm, α = 533nm, β = 570nm) of the metallated compound is consistent with that of a vanadyl porphyrin with a free-base (M+H) of 535. Collision-induced mass spectra displays mass losses of 43 and 57 daltons, which are consistent with an extended alkyl chain at the C-8 position. Extended alkyl chains at C-8 are exclusively associated with porphyrins derived from bacteriochlorophyll c, d or e. The presence of bacterioporphyrins is congruous with the episodic presence of anoxic and sulfidic conditions in the photic zone. What is surprising is that a bacteriochlorophyll- derived porphyrin is the most abundant in these sequences, and their study may help to elucidate the conditions surrounding the F-F mass extinction, and further constrain the fluctuations in marine oxygen content in the Upper Devonian Appalachian Basin.

Upper Gastrointestinal Stent Insertion in Malignant and Benign Disorders

Science.gov (United States)

Kang, Hyoun Woo

2015-01-01

Upper gastrointestinal (GI) stents are increasingly being used to manage upper GI obstructions. Initially developed for palliative treatment of esophageal cancer, upper GI stents now play an emerging role in benign strictures of the upper GI tract. Because recurrent obstruction and stent-related complications are common, new modifications of stents have been implemented. Self-expandable metal stents (SEMS) have replaced older plastic stents. In addition, newly designed SEMS have been developed to prevent complications. This review provides an overview of the various types, indications, methods, complications, and clinical outcomes of upper GI stents in a number of malignant and benign disorders dividing the esophagus and gastroduodenum. PMID:26064817

Cenomanian-Turanian anoxic event and potential petroleum source rocks of the Upper Benue Trough, Nigeria

International Nuclear Information System (INIS)

Mohammed, B.

2004-01-01

Foraminiferal palaeoenviromental studies particularly planktonic/benthonic (p/b) ratio have been used to demarcate anoxic horizon within the Cenomanian-Turonian sequence of the Upper Benue trough. The foraminiferal faunal assemblages indicate a deep marine .anoxic I sequences. Geochemical analysis of organic matter yielded TOC values that are generally fair to moderate with average of 0.70,2.05 and 0.44% in Dukkul, Pindiga and Gongila Formations respectively. Hydrogen indices also indicate preponderance of gas -prone terrestrial type III organic matter. This seems to be inconsistent with anoxic/dysoxic environments in which organic matter is generally expected to be commonly more abundant, better preserved and more lipid rich. Therefore, it is suggested here that such a relatively deep marine anoxic environment was subsequently raised tectonically to very shallow levels (raised oxygen-minimum zone) where terrestrial organic matter were washed into the anoxic water. These terrestrial contributions diluted and downgraded the anoxic level such that TOCs are generally low to moderate and organic matter became generally of type III and IV

Fine scale distributions of porosity and particulate excess 210Pb, organic carbon and CaCO3 in surface sediments of the deep equatorial Pacific

International Nuclear Information System (INIS)

Jahnke, R.A.; Emerson, S.R.; Cochran, J.K.; Hirschberg, D.J.

1986-01-01

Sediment samples were recovered from the central equatorial Pacific Ocean, sectioned at 1-mm intervals, and analyzed for porosity, organic carbon, excess 210 Pb and CaCO 3 . Steep porosity gradients were measured in the upper 1 cm of the sediment column with extremely high values observed near the sediment surface. Similarly, particulate organic carbon contents are highest at the sediment surface, decrease sharply in the upper 1 cm, and are relatively constant between 1 and 5 cm. CaCO 3 values, on the other hand, are lowest at the sediment surface and increase to a constant value below 5-10 mm depth. At the carbonate ooze sites, excess 210 Pb is present throughout the upper 5 cm of the sediments suggesting relatively rapid particle mixing rates. However, extremely high excess 210 Pb activities (> 100 dpm/g) are observed at the sediment surface with sharp gradients present in the upper 1 cm which would suggest slow rates of mixing. This apparent contradiction along with the major features of the CaCO 3 and particulate organic carbon profiles can be explained by a particle-selective feeding mechanism in which organic carbon, excess 210 Pb-enriched particles are preferentially maintained at the sediment surface via ingestion and defecation by benthic organisms. (orig.)

Unsedated Flexible Upper Gastrointestinal Endoscopy: Need for ...

African Journals Online (AJOL)

Background: To determine the incidence of oxygen desaturation and whether routine oxygen monitoring is necessary during unsedated diagnostic flexible upper gastrointestinal endoscopy. Methods: A prospective study involving 54 consecutive in and out patients who had diagnostic upper gastrointestinal endoscopy at ...

Occupational upper airway disease: how work affects the nose

NARCIS (Netherlands)

Hox, V.; Steelant, B.; Fokkens, W.; Nemery, B.; Hellings, P. W.

2014-01-01

Chronic inflammation of the upper airways is common and can arbitrarily be divided into rhinitis and rhinosinusitis. Infection and allergy represent two well-characterized and most frequently diagnosed etiologies of upper airway inflammation. Persistent upper airway inflammation caused by agents

A STUDY ON UPPER GASTROINTESTINAL ENDOSCOPIC FINDINGS IN PATIENTS WITH UPPER GASTROINTESTINAL BLEEDING

Directory of Open Access Journals (Sweden)

Salla Surya Prakasa Rao

2016-10-01

Full Text Available BACKGROUND Vomiting of blood almost always proximal to the ligament of Treitz is the upper gastrointestinal haemorrhage. The incidence of acute upper gastrointestinal haemorrhage has been estimated to be 50-100 per 1,00,000 person per year, with an annual hospitalization rate of approximately 100 per 1, 00,000 hospital admission. This study is to find out the prevalence of nature of lesion on Upper Gastrointestinal Endoscopy in patients admitted for Gastrointestinal bleeding. (UGI Bleed. MATERIALS AND METHODS Place of Study- Department of General Medicine, Andhra Medical College, Visakhapatnam, India. Type of Study- Prospective study. Period of Study- July 2015 to August 2016. RESULTS The Results Study on Endoscopic Findings in Upper Gastro Intestinal Bleed are 1. The peptic ulcer disease was the most common lesion found on endoscopy with prevalence of 54%. 2. Varices contributes second common lesion, next to peptic ulcer disease in UGI bleed with prevalence of 16%. 3. Minor UGI bleed was the commonest presentation. Majority of lesions (60% presented with minor UGI bleed, 28% lesions presented as moderate UGI bleed. Only 8% presented as major UGI bleed. 4. Varices account for the most common cause for major UGI bleed contributing 50%. 5. Gastric ulcer was commonest lesions accounting for 37 cases (37% among 72 cases having single acid peptic lesions on endoscopy. The second most common is duodenal ulcer (31%. 6. Multiple lesions were found in 10% of cases. Peptic ulcer lesions were found in 20% of total number of varices cases. CONCLUSION Peptic ulcer disease was found to be most common lesion causing UGI bleed, with most common presentation as minor UGI bleed and variceal bleed being most common cause of major UGI bleed.

Organics, Meteoritic Material, and other Elements in High Altitude Aerosols

Science.gov (United States)

Mahoney, M.; Murphy, D. M.; Thomson, D. S.

1998-01-01

Recent in situ measurements of the chemical composition of single aerosol particles at altitudes up to 19 km have revealed a number of surprising features about ambient particles. Upper tropospheric aerosols in the study region often contained more organic material than sulfate.

Geology and undiscovered resource assessment of the potash-bearing Pripyat and Dnieper-Donets Basins, Belarus and Ukraine

Science.gov (United States)

Cocker, Mark D.; Orris, Greta J.; Dunlap, Pamela; Lipin, Bruce R.; Ludington, Steve; Ryan, Robert J.; Słowakiewicz, Mirosław; Spanski, Gregory T.; Wynn, Jeff; Yang, Chao

2017-08-03

Undiscovered potash resources in the Pripyat Basin, Belarus, and Dnieper-Donets Basin, Ukraine, were assessed as part of a global mineral resource assessment led by the U.S. Geological Survey (USGS). The Pripyat Basin (in Belarus) and the Dnieper-Donets Basin (in Ukraine and southern Belarus) host stratabound and halokinetic Upper Devonian (Frasnian and Famennian) and Permian (Cisuralian) potash-bearing salt. The evaporite basins formed in the Donbass-Pripyat Rift, a Neoproterozoic continental rift structure that was reactivated during the Late Devonian and was flooded by seawater. Though the rift was divided, in part by volcanic deposits, into the separate Pripyat and Dnieper-Donets Basins, both basins contain similar potash‑bearing evaporite sequences. An Early Permian (Cisuralian) sag basin formed over the rift structure and was also inundated by seawater resulting in another sequence of evaporite deposition. Halokinetic activity initiated by basement faulting during the Devonian continued at least into the Permian and influenced potash salt deposition and structural evolution of potash-bearing salt in both basins.Within these basins, four areas (permissive tracts) that permit the presence of undiscovered potash deposits were defined by using geological criteria. Three tracts are permissive for stratabound potash-bearing deposits and include Famennian (Upper Devonian) salt in the Pripyat Basin, and Famennian and Cisuralian (lower Permian) salt in the Dnieper-Donets Basin. In addition, a tract was delineated for halokinetic potash-bearing Famennian salt in the Dnieper-Donets Basin.The Pripyat Basin is the third largest source of potash in the world, producing 6.4 million metric tons of potassium chloride (KCl) (the equivalent of about 4.0 million metric tons of potassium oxide or K2O) in 2012. Potash production began in 1963 in the Starobin #1 mine, near the town of Starobin, Belarus, in the northwestern corner of the basin. Potash is currently produced from

Upper airway evaluation

International Nuclear Information System (INIS)

Hoffman, E.A.; Gefter, W.B.; Schnall, M.; Nordberg, J.; Listerud, J.; Lenkinski, R.E.

1988-01-01

The authors are evaluating upper-airway sleep disorders with magnetic resonance (MR) imaging and x-ray cine computed tomography (CT). Fixed structural anatomy is visualized with multisection spin-echo MR imaging, the dynamic component with cine CT. Unique aspects of the study are described in this paper

Magmatic record of Late Devonian arc-continent collision in the northern Qiangtang, Tibet: Implications for the early evolution of East Paleo-Tethys Ocean

Science.gov (United States)

Dan, Wei; Wang, Qiang; Zhang, Xiu-Zheng; Zhang, Chunfu; Tang, Gong-Jian; Wang, Jun; Ou, Quan; Hao, Lu-Lu; Qi, Yue

2018-05-01

Recognizing the early-developed intra-oceanic arc is important in revealing the early evolution of East Paleo-Tethys Ocean. In this study, new SIMS zircon U-Pb dating, O-Hf isotopes, and whole-rock geochemical data are reported for the newly-discovered Late Devonian-Early Carboniferous arc in Qiangtang, central Tibet. New dating results reveal that the eastern Riwanchaka volcanic rocks were formed at 370-365 Ma and were intruded by the 360 Ma Gangma Co alkali feldspar granites. The volcanic rocks consist of basalts, andesites, dacites, and rhyodacites, whose geochemistry is similar to that typical of subduction-related volcanism. The basalts and andesites were generated by partial melting of the fluid and sediment-melt metasomatized mantle, respectively. The rhyodacites and dacites were probably derived from the fractional crystallization of andesites and from partial melting of the juvenile underplated mafic rocks, respectively. The Gangma Co alkali feldspar granites are A-type granites, and were possibly derived by partial melting of juvenile underplated mafic rocks in a post-collisional setting. The 370-365 Ma volcanic arc was characterized by basalts with oceanic arc-like Ce/Yb ratios and by rhyodacites with mantle-like or slightly higher zircon δ18O values, and it was associated with the contemporary ophiolites. Thus, we propose that it is the earliest intra-oceanic arc in the East Paleo-Tethys Ocean, and was accreted to the Northern Qiangtang Terrane during 365-360 Ma.

Upper Extremity Deep Vein Thromboses: The Bowler and the Barista

Directory of Open Access Journals (Sweden)

Seth Stake

2016-01-01

Full Text Available Effort thrombosis of the upper extremity refers to a deep venous thrombosis of the upper extremity resulting from repetitive activity of the upper limb. Most cases of effort thrombosis occur in young elite athletes with strenuous upper extremity activity. This article reports two cases who both developed upper extremity deep vein thromboses, the first being a 67-year-old bowler and the second a 25-year-old barista, and illustrates that effort thrombosis should be included in the differential diagnosis in any patient with symptoms concerning DVT associated with repetitive activity. A literature review explores the recommended therapies for upper extremity deep vein thromboses.

Upper Extremity Deep Vein Thromboses: The Bowler and the Barista.

Science.gov (United States)

Stake, Seth; du Breuil, Anne L; Close, Jeremy

2016-01-01

Effort thrombosis of the upper extremity refers to a deep venous thrombosis of the upper extremity resulting from repetitive activity of the upper limb. Most cases of effort thrombosis occur in young elite athletes with strenuous upper extremity activity. This article reports two cases who both developed upper extremity deep vein thromboses, the first being a 67-year-old bowler and the second a 25-year-old barista, and illustrates that effort thrombosis should be included in the differential diagnosis in any patient with symptoms concerning DVT associated with repetitive activity. A literature review explores the recommended therapies for upper extremity deep vein thromboses.

Antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or chronic liver disease.

Science.gov (United States)

Martí-Carvajal, Arturo J; Solà, Ivan

2015-06-09

Upper gastrointestinal bleeding is one of the most frequent causes of morbidity and mortality in the course of liver cirrhosis. People with liver disease frequently have haemostatic abnormalities such as hyperfibrinolysis. Therefore, antifibrinolytic amino acids have been proposed to be used as supplementary interventions alongside any of the primary treatments for upper gastrointestinal bleeding in people with liver diseases. This is an update of this Cochrane review. To assess the beneficial and harmful effects of antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or chronic liver disease. We searched The Cochrane Hepato-Biliary Controlled Trials Register (February 2015), Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 2 of 12, 2015), MEDLINE (Ovid SP) (1946 to February 2015), EMBASE (Ovid SP) (1974 to February 2015), Science Citation Index EXPANDED (1900 to February 2015), LILACS (1982 to February 2015), World Health Organization Clinical Trials Search Portal (accessed 26 February 2015), and the metaRegister of Controlled Trials (accessed 26 February 2015). We scrutinised the reference lists of the retrieved publications. Randomised clinical trials irrespective of blinding, language, or publication status for assessment of benefits and harms. Observational studies for assessment of harms. We planned to summarise data from randomised clinical trials using standard Cochrane methodologies and assessed according to the GRADE approach. We found no randomised clinical trials assessing antifibrinolytic amino acids for treating upper gastrointestinal bleeding in people with acute or chronic liver disease. We did not identify quasi-randomised, historically controlled, or observational studies in which we could assess harms. This updated Cochrane review identified no randomised clinical trials assessing the benefits and harms of antifibrinolytic amino acids for upper gastrointestinal bleeding in people with acute or

Sequence stratigraphy, organic petrology and chemistry applied to the upper and lower coal seams in the Candiota Coalfield, Parana Basin, RS, Brazil

Energy Technology Data Exchange (ETDEWEB)

Oliveira, J.S. de; Kalkreuth, W. [Instituto de Geociencias, UFRGS, Porto Alegre (Brazil)

2010-12-01

The Permian age coal seams in the Candiota Coalfield represent the largest coal deposit of the country. Currently two seams are mined, called ''Camada Candiota Superior'' and ''Camada Candiota Inferior''. The other coal seams of the coalfield, seams S1-S9 (upper seams) and I1-I5 (lower seams) have as yet not been exploited. The objective of this paper is to perform a detailed sequence stratigraphic, petrologic and chemical study of the upper and lower coal seams, thereby generating data for assisting in the development and better use of the coal-bearing interval. The methodology includes application of the concepts of sequence stratigraphy, which includes the lithological interpretation of the core to establish the depositional environments and genetic correlation between facies associations to define parasequences and bounding surfaces; coal petrology (analysis of the reflectance of vitrinite, determination of the petrographic composition of the coals by maceral analyses), and chemical analyses such as sulphur determination, proximate analyses (ash, moisture, volatile matter, and fixed carbon), and elemental analyses. Three main depositional systems were so far identified: alluvial fan, fluvial system, lagoonal estuary system. This study shows that coal development was controlled by accommodation/accumulation rates, with coal seams with greater thickness and lateral continuity being formed within the transgressive systems tract (lagoonal depositional system) of parasequence 2 (PS2), indicating that the accumulation rates of the peat and distribution of the coal seams were controlled by stratigraphic setting. Vitrinite reflectances for the upper and lower coal seams are indicative of subbituminous rank (Rrandom = 0.36-0.47%), with evidence that anomalously low reflectance values are related to high mineral-matter contents. Maceral composition is highly variable, with some coal seams being extremely rich in inertinite (up to

A classic Late Frasnian chondrichthyan assemblage from southern Belgium

Science.gov (United States)

Ginter, Michał; Gouwy, Sofie; Goolaerts, Stijn

2017-09-01

Samples from the Upper Frasnian (Devonian) of Lompret Quarry and Nismes railway section in Dinant Synclinorium, southern Belgium, yielded several chondrichthyan teeth and scales. The teeth belong to three genera: Phoebodus, Cladodoides and Protacrodus. The comparison with selected Late Frasnian chondrichthyan assemblages from the seas between Laurussia and Gondwana revealed substantial local differences of taxonomic composition due to palaeoenvironmental conditions, such as depth, distance to submarine platforms, oxygenation of water, and possibly also temperature. The assemblage from Belgium, with its high frequency of phoebodonts, is the most similar to that from the Ryauzyak section, South Urals, Russia, and the Horse Spring section, Canning Basin, Australia.

Helicopter-based lidar system for monitoring the upper ocean and terrain surface

International Nuclear Information System (INIS)

Lee, Kwi Joo; Park, Youngsik; Bunkin, Alexey; Pershin, Serguei; Voliak, Konstantin; Nunes, Raul

2002-01-01

A compact helicopter-based lidar system is developed and tested under laboratory and field conditions. It is shown that the lidar can measure concentrations of chlorophyll a and dissolved organic matter at the surface of water bodies, detect fluorescence spectra of ground vegetation at a distance of up to 530 m, and determine the vertical profile of light-scattering particle concentration in the upper ocean. The possibilities of the lidar system are demonstrated by detection of polluted areas at the ocean surface, by online monitoring of three-dimensional distribution of light-scattering layers, and by recognition of plant types and physiological states

A 12 years audit of upper gastrointestinal endoscopic procedures

International Nuclear Information System (INIS)

Khurram, M.; Khaar, H.B.; Hasan, Z.; Umar, M.; Javed, S.; Asghar, T.; Minhas, Z.; Akbar, A.; Atta, N.; Nassar, F.; Sultana, Q.; Pervaiz, A.; Masoom, A.

2003-01-01

Objective: Evaluation of upper gastrointestinal (GI) endoscopy in terms of indications, diagnostic efficacy, and diseases diagnosed. Results: Of the 8481 patients, 4935 (58.2%) were female and 3546 (41.8%) male. Mean patient age was 40.5 years. Dyspepsia (42.6%), upper GI bleed (32.8%), and evaluation of chronic liver disease (10.2%) were common indications of the procedure. An endoscopic diagnosis was possible in 82.6% patients. Varices, gastritis, duodenitis, and combined lesions were common endoscopic diagnosis. Gastritis and duodenitis were most frequent causes of upper GI bleed. We noted more gastric ulcers compared to duodenal ulcers. Females had significantly more normal endoscopies, p-value = 0.02. Conclusion: Upper GI endoscopy is an effective procedure. Dyspepsia evaluation is commonest indication for upper GI endoscopy in our patients. Etiology of upper GI bleed, and incidence of duodenal ulcer compared to gastric ulcer in our patients are different than described in literature. Females have significantly more normal endoscopies. (author)

Graphic Organizers and Students with Learning Disabilities: A Meta-Analysis

Science.gov (United States)

Dexter, Douglas D.; Hughes, Charles A.

2011-01-01

This meta-analysis reviews experimental and quasi-experimental studies in which upper-elementary, intermediate, and secondary students with learning disabilities learned from graphic organizers. Following an exhaustive search for studies meeting specified design criteria, 55 standardized mean effect sizes were extracted from 16 articles involving…

ACA Federal Upper Limits

Data.gov (United States)

U.S. Department of Health & Human Services — Affordable Care Act Federal Upper Limits (FUL) based on the weighted average of the most recently reported monthly average manufacturer price (AMP) for...

ON COMPUTING UPPER LIMITS TO SOURCE INTENSITIES

International Nuclear Information System (INIS)

Kashyap, Vinay L.; Siemiginowska, Aneta; Van Dyk, David A.; Xu Jin; Connors, Alanna; Freeman, Peter E.; Zezas, Andreas

2010-01-01

A common problem in astrophysics is determining how bright a source could be and still not be detected in an observation. Despite the simplicity with which the problem can be stated, the solution involves complicated statistical issues that require careful analysis. In contrast to the more familiar confidence bound, this concept has never been formally analyzed, leading to a great variety of often ad hoc solutions. Here we formulate and describe the problem in a self-consistent manner. Detection significance is usually defined by the acceptable proportion of false positives (background fluctuations that are claimed as detections, or Type I error), and we invoke the complementary concept of false negatives (real sources that go undetected, or Type II error), based on the statistical power of a test, to compute an upper limit to the detectable source intensity. To determine the minimum intensity that a source must have for it to be detected, we first define a detection threshold and then compute the probabilities of detecting sources of various intensities at the given threshold. The intensity that corresponds to the specified Type II error probability defines that minimum intensity and is identified as the upper limit. Thus, an upper limit is a characteristic of the detection procedure rather than the strength of any particular source. It should not be confused with confidence intervals or other estimates of source intensity. This is particularly important given the large number of catalogs that are being generated from increasingly sensitive surveys. We discuss, with examples, the differences between these upper limits and confidence bounds. Both measures are useful quantities that should be reported in order to extract the most science from catalogs, though they answer different statistical questions: an upper bound describes an inference range on the source intensity, while an upper limit calibrates the detection process. We provide a recipe for computing upper

Pyomyositis in the upper Negro river basin, Brazilian Amazonia

DEFF Research Database (Denmark)

Borges, Alvaro Humberto Diniz; Faragher, Brian; Lalloo, David G

2012-01-01

Pyomyositis remains poorly documented in tropical Latin America. We therefore performed a retrospective review of cases admitted to a hospital in the upper Negro river basin during 2002-2006. Seasonality was assessed by the cosinor model and independent predictors of outcome were identified...... lesions). Staphylococcus aureus was the only identified infecting organism (18 of 20 culture results, 90%). Complications occurred in 17 patients (20.7%) and the case fatality rate was 2.4%. Children were more likely to present with eosinophilia than adults (OR= 4.20, 95% CI 1.08-16.32, p=0.......048), but no other significant differences regarding clinical presentation and outcomes were observed. The time-to-fever resolution was the only independent determinant of poor outcome (OR=1.52, 95% CI 1.22-1.92, p...

Estimating the physicochemical properties of polyhalogenated aromatic and aliphatic compounds using UPPER: part 1. Boiling point and melting point.

Science.gov (United States)

Admire, Brittany; Lian, Bo; Yalkowsky, Samuel H

2015-01-01

The UPPER (Unified Physicochemical Property Estimation Relationships) model uses enthalpic and entropic parameters to estimate 20 biologically relevant properties of organic compounds. The model has been validated by Lian and Yalkowsky on a data set of 700 hydrocarbons. The aim of this work is to expand the UPPER model to estimate the boiling and melting points of polyhalogenated compounds. In this work, 19 new group descriptors are defined and used to predict the transition temperatures of an additional 1288 compounds. The boiling points of 808 and the melting points of 742 polyhalogenated compounds are predicted with average absolute errors of 13.56 K and 25.85 K, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

Upper High School Students' Understanding of Electromagnetism

Science.gov (United States)

Saglam, Murat; Millar, Robin

2006-01-01

Although electromagnetism is an important component of upper secondary school physics syllabuses in many countries, there has been relatively little research on students' understanding of the topic. A written test consisting of 16 diagnostic questions was developed and used to survey the understanding of electromagnetism of upper secondary school…

The Development of the Flat-Knitted Shaped Uppers based on Ergonomics

Directory of Open Access Journals (Sweden)

Lu Zhiwen

2016-06-01

Full Text Available To achieve the efficiency and specification of the flat-knitted uppers design, the basic patterns of uppers are made from shoe lasts based on the research on the characteristics of human’s feet and wearability requirements on uppers. The knitting technology for half-shaped and fully shaped uppers was formed after the shear deformation of basic pattern and combination with flat knitting technology. As regards to the functional requirements on key parts of uppers, the structures of flat-knitted shaped uppers were intensively analysed and studied, dividing them into two categories (functional structure and decorative structure, discussing the knitting methods and advantages of different structure, and finally experimentally proving that the planar pattern of flat knitted uppers can apply to the design of flat-knitted uppers and achieve the combination of functionality and artistry of sneakers after combining with structural changes, with a great significance on the achievement of the efficient production of uppers and the enhancement of its commercial value.

Principal aspects of petrographical examination of rock salts to assess their suitability for radioactive waste disposal

International Nuclear Information System (INIS)

Shekhunova, S.B.

1995-01-01

To solve the problem of high-level radioactive waste (HLRW) isolation in Ukraine a preparatory stage of feasibility study as to the construction of a pilot laboratory has been completed. Salty formations are considered as possible host rocks for HLRW isolation. 7 salt formations located in 5 regions of Ukraine have been examined and was found that only two, i.e. the Upper Devonian and Lower Permian halogenic formations of the Dnieper-Donets Depression appeared to have considerable promise for these purposes. In these two formations 4 zones with 12 candidate-sites were selected. The promising zones are located both in bedded salt and in salt domes. Analytical treatment our previous studies as well as a special-purpose research have resulted in designing packages of the schematic information models for the zones and some candidate-sites. Now we are preparing to start exploration drilling at several promising structures. Research has been carried out by the Institute of Geological Sciences (National Academy of Sciences of Ukraine) on budget and contract financial basis with the participation of branch institutes and the State Committee on Nuclear power Utilization (Goskomatom). The drilling and geophysical data were presented by Goskomgeologiya production organizations

Analysis of the upper-truncated Weibull distribution for wind speed

International Nuclear Information System (INIS)

Kantar, Yeliz Mert; Usta, Ilhan

2015-01-01

Highlights: • Upper-truncated Weibull distribution is proposed to model wind speed. • Upper-truncated Weibull distribution nests Weibull distribution as special case. • Maximum likelihood is the best method for upper-truncated Weibull distribution. • Fitting accuracy of upper-truncated Weibull is analyzed on wind speed data. - Abstract: Accurately modeling wind speed is critical in estimating the wind energy potential of a certain region. In order to model wind speed data smoothly, several statistical distributions have been studied. Truncated distributions are defined as a conditional distribution that results from restricting the domain of statistical distribution and they also cover base distribution. This paper proposes, for the first time, the use of upper-truncated Weibull distribution, in modeling wind speed data and also in estimating wind power density. In addition, a comparison is made between upper-truncated Weibull distribution and well known Weibull distribution using wind speed data measured in various regions of Turkey. The obtained results indicate that upper-truncated Weibull distribution shows better performance than Weibull distribution in estimating wind speed distribution and wind power. Therefore, upper-truncated Weibull distribution can be an alternative for use in the assessment of wind energy potential

Upper respiratory tract (image)

Science.gov (United States)

The major passages and structures of the upper respiratory tract include the nose or nostrils, nasal cavity, mouth, throat (pharynx), and voice box (larynx). The respiratory system is lined with a mucous membrane that ...

Laboratory test variables useful for distinguishing upper from lower gastrointestinal bleeding.

Science.gov (United States)

Tomizawa, Minoru; Shinozaki, Fuminobu; Hasegawa, Rumiko; Shirai, Yoshinori; Motoyoshi, Yasufumi; Sugiyama, Takao; Yamamoto, Shigenori; Ishige, Naoki

2015-05-28

To distinguish upper from lower gastrointestinal (GI) bleeding. Patient records between April 2011 and March 2014 were analyzed retrospectively (3296 upper endoscopy, and 1520 colonoscopy). Seventy-six patients had upper GI bleeding (Upper group) and 65 had lower GI bleeding (Lower group). Variables were compared between the groups using one-way analysis of variance. Logistic regression was performed to identify variables significantly associated with the diagnosis of upper vs lower GI bleeding. Receiver-operator characteristic (ROC) analysis was performed to determine the threshold value that could distinguish upper from lower GI bleeding. Hemoglobin (P = 0.023), total protein (P = 0.0002), and lactate dehydrogenase (P = 0.009) were significantly lower in the Upper group than in the Lower group. Blood urea nitrogen (BUN) was higher in the Upper group than in the Lower group (P = 0.0065). Logistic regression analysis revealed that BUN was most strongly associated with the diagnosis of upper vs lower GI bleeding. ROC analysis revealed a threshold BUN value of 21.0 mg/dL, with a specificity of 93.0%. The threshold BUN value for distinguishing upper from lower GI bleeding was 21.0 mg/dL.

Survey of upper extremity injuries among martial arts participants.

Science.gov (United States)

Diesselhorst, Matthew M; Rayan, Ghazi M; Pasque, Charles B; Peyton Holder, R

2013-01-01

To survey participants at various experience levels of different martial arts (MA) about upper extremity injuries sustained during training and fighting. A 21-s question survey was designed and utilised. The survey was divided into four groups (Demographics, Injury Description, Injury Mechanism, and Miscellaneous information) to gain knowledge about upper extremity injuries sustained during martial arts participation. Chi-square testing was utilised to assess for significant associations. Males comprised 81% of respondents. Involvement in multiple forms of MA was the most prevalent (38%). The hand/wrist was the most common area injured (53%), followed by the shoulder/upper arm (27%) and the forearm/elbow (19%). Joint sprains/muscle strains were the most frequent injuries reported overall (47%), followed by abrasions/bruises (26%). Dislocations of the upper extremity were reported by 47% of participants while fractures occurred in 39%. Surgeries were required for 30% of participants. Females were less likely to require surgery and more likely to have shoulder and elbow injuries. Males were more likely to have hand injuries. Participants of Karate and Tae Kwon Do were more likely to have injuries to their hands, while participants of multiple forms were more likely to sustain injuries to their shoulders/upper arms and more likely to develop chronic upper extremity symptoms. With advanced level of training the likelihood of developing chronic upper extremity symptoms increases, and multiple surgeries were required. Hand protection was associated with a lower risk of hand injuries. Martial arts can be associated with substantial upper extremity injuries that may require surgery and extended time away from participation. Injuries may result in chronic upper extremity symptoms. Hand protection is important for reducing injuries to the hand and wrist.

Atmospheric Chemistry of Micrometeoritic Organic Compounds

Science.gov (United States)

Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

2011-01-01

Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

Local Acetaldehyde—An Essential Role in Alcohol-Related Upper Gastrointestinal Tract Carcinogenesis

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Mikko T. Nieminen

2018-01-01

Full Text Available The resident microbiome plays a key role in exposure of the upper gastrointestinal (GI tract mucosa to acetaldehyde (ACH, a carcinogenic metabolite of ethanol. Poor oral health is a significant risk factor for oral and esophageal carcinogenesis and is characterized by a dysbiotic microbiome. Dysbiosis leads to increased growth of opportunistic pathogens (such as Candida yeasts and may cause an up to 100% increase in the local ACH production, which is further modified by organ-specific expression and gene polymorphisms of ethanol-metabolizing and ACH-metabolizing enzymes. A point mutation in the aldehyde dehydrogenase 2 gene has randomized millions of alcohol consumers to markedly increased local ACH exposure via saliva and gastric juice, which is associated with a manifold risk for upper GI tract cancers. This human cancer model proves conclusively the causal relationship between ACH and upper GI tract carcinogenesis and provides novel possibilities for the quantitative assessment of ACH carcinogenicity in the human oropharynx. ACH formed from ethanol present in “non-alcoholic” beverages, fermented food, or added during food preparation forms a significant epidemiologic bias in cancer epidemiology. The same also concerns “free” ACH present in mutagenic concentrations in multiple beverages and foodstuffs. Local exposure to ACH is cumulative and can be reduced markedly both at the population and individual level. At best, a person would never consume tobacco, alcohol, or both. However, even smoking cessation and moderation of alcohol consumption are associated with a marked decrease in local ACH exposure and cancer risk, especially among established risk groups.

Tidal Influence on Nutrients Status and Phytoplankton Population of Okpoka Creek, Upper Bonny Estuary, Nigeria

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O. A. Davies

2013-01-01

Full Text Available Okpoka Creek of the Upper Bonny Estuary in the Niger Delta is a tidal creek receiving organic anthropogenic effluents from its environs. The study investigated the influence of tides (low and high on the species composition, diversity, abundance, and distribution of phytoplankton. The surface water and phytoplankton samples were collected monthly from May 2004 to April 2006 at both tides from ten stations according to standard methods. Phytoplankton was identified microscopically. Species diversity was calculated using standard indices. Data analyses were done using analysis of variance, Duncan multiple range, and descriptive statistics. Phosphate and ammonia exceeded international acceptable levels of 0.10 mg/L for natural water bodies indicating high nutrient status, organic matter, and potential pollutants. A total of 158 species of phytoplankton were identified. Diatoms dominated the phytoplankton (62.9%. Diversity indices of diatoms were 1.5±0.03 (Margalef and 0.8±0.01 (Shannon. Pollution-indicator species such as Navicula microcephala, Nitzschia sigma, Synedra ulna (diatoms, Cladophora glomerata (green alga, Euglena acus (euglenoid, Anabeana spiroides (blue-green alga, and Ceratium furca (dinoflagellate were recorded at either only low, high or both tides. Concerted environmental surveillance on Upper Bonny Estuary is advocated to reduce the inflow of pollutants from the Bonny Estuary into this Creek caused by tidal influence.

Upper-Level Waves of Synoptic Scale at Midlatitudes

Science.gov (United States)

Rivest, Chantal

1990-01-01

Upper-level waves of synoptic scale are important dynamical entities at midlatitudes. They often induce surface cyclogenesis (cf. Peterssen and Smebye, 1971), and their life duration is typically longer than time scales for disruption by the ambient shear (Sanders, 1988). The objectives of the present thesis are to explain the maintenance and genesis of upper-level synoptic-scale waves in the midlatitude flow. We develop an analytical model of waves on generalized Eady basic states that have uniform tropospheric and stratospheric potential vorticity, but allow for the decay of density with height. The Eady basic state represents the limiting case of infinite stratospheric stability and constant density. We find that the Eady normal mode characteristics hold in the presence of realistic tropopause and stratosphere. In particular, the basic states studied support at the synoptic scale upper-level normal modes. These modes provide simple models for the dynamics of upper-level synoptic-scale waves, as waves supported by the large latitudinal gradients of potential vorticity at the tropopause. In the presence of infinitesimal positive tropospheric gradients of potential vorticity, the upper-level normal mode solutions no longer exist, as was demonstrated in Green (1960). Disappearance of the normal mode solution when a parameter changes slightly represents a dilemma that we seek to understand. We examine what happens to the upper-level normal modes in the presence of tropospheric gradients of potential vorticity in a series of initial -value experiments. Our results show that the normal modes become slowly decaying quasi-modes. Mathematically the quasi-modes consist of a superposition of singular modes sharply peaked in the phase speed domain, and their decay proceeds as the modes interfere with one another. We repeat these experiments in basic states with a smooth tropopause in the presence of tropospheric and stratospheric gradients, and similar results are obtained

Arterial variations of upper limb: a case report

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Vollala V

2005-01-01

Full Text Available Variations of upper limb arteries are common and there are many reports about this subject. We report multiple variations in arterial pattern of upper extremity, which were encountered in a single cadaver.

BACTERIAL PROFILE, ANTIBIOTIC SENSITIVITY AND RESISTANCE OF LOWER RESPIRATORY TRACT INFECTIONS IN UPPER EGYPT

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Gamal Agmy

2013-09-01

Full Text Available BACKGROUND: Lower respiratory tract infections (LRTI account for a considerable proportion of morbidity and antibiotic use. We aimed to identify the causative bacteria, antibiotic sensitivity and resistance of hospitalized adult patients due to LRTI in Upper Egypt. METHODS: A multicentre prospective study was performed at 3 University Hospitals for 3 years. Samples included sputum or bronchoalveolar lavage (BAL for staining and culture, and serum for serology. Samples were cultured on 3 bacteriological media (Nutrient, Chocolate ,MacConkey's agars.Colonies were identified via MicroScan WalkAway-96. Pneumoslide IgM kit was used for detection of atypical pathogens via indirect immunofluorescent assay. RESULTS: The predominant isolates in 360 patients with CAP were S.pneumoniae (36%, C. pneumoniae (18%, and M. pneumoniae (12%. A higher sensitivity was recorded for moxifloxacin, levofloxacin, macrolides, and cefepime. A higher of resistance was recorded for doxycycline, cephalosporins, and β-lactam-β-lactamase inhibitors. The predominant isolates in 318 patients with HAP were, methicillin-resistant Staphylococcus aureus; MRSA (23%, K. pneumoniae (14%, and polymicrobial in 12%. A higher sensitivity was recorded for vancomycin, ciprofloxacin, and moxifloxacin. Very high resistance was recorded for β-lactam-β-lactamase inhibitors and cephalosporins. The predominant organisms in 376 patients with acute exacerbation of chronic obstructive pulmonary diseases (AECOPD were H. influnzae (30%, S. pneumoniae (25%, and M. catarrhalis(18%. A higher sensitivity was recorded for moxifloxacin, macrolides and cefepime. A higher rate of resistance was recorded for aminoglycosides and cephalosporins CONCLUSIONS: The most predominant bacteria for CAP in Upper Egypt are S. pneumoniae and atypical organisms, while that for HAP are MRSA and Gram negative bacteria. For acute exacerbation of COPD,H.influnzae was the commonest organism. Respiratory quinolones

Organic Optical Sensor Based on Monolithic Integration of Organic Electronic Devices

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Hoi Lam Tam

2015-09-01

Full Text Available A novel organic optical sensor that integrates a front organic light-emitting diode (OLED and an organic photodiode (OPD is demonstrated. The stripe-shaped cathode is used in the OLED components to create light signals, while the space between the stripe-shaped cathodes serves as the detection window for integrated OPD units. A MoO3 (5 nm/Ag (15 nm bi-layer inter-electrode is interposed between the vertically stacked OLED and OPD units, serving simultaneously as the cathode for the front OLED and an anode for the upper OPD units in the sensor. In the integrated sensor, the emission of the OLED units is confined by the area of the opaque stripe-shaped cathodes, optimized to maximize the reflected light passing through the window space for detection by the OPD components. This can ensure high OLED emission output, increasing the signal/noise ratio. The design and fabrication flexibility of an integrated OLED/OPD device also has low cost benefits, and is light weight and ultra-thin, making it possible for application in wearable units, finger print identification, image sensors, smart light sources, and compact information systems.

Upper Limit for Regional Sea Level Projections

Science.gov (United States)

Jevrejeva, Svetlana; Jackson, Luke; Riva, Riccardo; Grinsted, Aslak; Moore, John

2016-04-01

With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. With probabilistic approach we produce regional sea level projections taking into account large uncertainties associated with Greenland and Antarctica ice sheets contribution. We calculate the upper limit (as 95%) for regional sea level projections by 2100 with RCP8.5 scenario, suggesting that for the most coastlines upper limit will exceed the global upper limit of 1.8 m.

Uranium distribution and sandstone depositional environments: oligocene and upper Cretaceous sediments, Cheyenne basin, Colorado

International Nuclear Information System (INIS)

Nibbelink, K.A.; Ethridge, F.G.

1984-01-01

Wyoming-type roll-front uranium deposits occur in the Upper Cretaceous Laramie and Fox Hills sandstones in the Cheyenne basin of northeastern Colorado. The location, geometry, and trend of specific depositional environments of the Oligocene White River and the Upper Cretaceous Laramie and Fox Hills formations are important factors that control the distribution of uranium in these sandstones. The Fox Hills Sandstone consists of up to 450 ft (140 m) of nearshore marine wave-dominated delta and barrier island-tidal channel sandstones which overlie offshore deposits of the Pierre Shale and which are overlain by delta-plain and fluvial deposits of the Laramie Formation. Uranium, which probably originated from volcanic ash in the White River Formation, was transported by groundwater through the fluvial-channel deposits of the White River into the sandstones of the Laramie and Fox Hills formations where it was precipitated. Two favorable depositional settings for uranium mineralization in the Fox Hills Sandstone are: (1) the landward side of barrier-island deposits where barrier sandstones thin and interfinger with back-barrier organic mudstones, and (2) the intersection of barrier-island and tidal channel sandstones. In both settings, sandstones were probably reduced during early burial by diagenesis of contained and adjacent organic matter. The change in permeability trends between the depositional strike-oriented barrier sandstones and the dip-oriented tidal-channel sandstones provided sites for dispersed groundwater flow and, as demonstrated in similar settings in other depositional systems, sites for uranium mineralization

PWR upper/lower internals shield

Energy Technology Data Exchange (ETDEWEB)

Homyk, W.A. [Indian Point Station, Buchanan, NY (United States)

1995-03-01

During refueling of a nuclear power plant, the reactor upper internals must be removed from the reactor vessel to permit transfer of the fuel. The upper internals are stored in the flooded reactor cavity. Refueling personnel working in containment at a number of nuclear stations typically receive radiation exposure from a portion of the highly contaminated upper intervals package which extends above the normal water level of the refueling pool. This same issue exists with reactor lower internals withdrawn for inservice inspection activities. One solution to this problem is to provide adequate shielding of the unimmersed portion. The use of lead sheets or blankets for shielding of the protruding components would be time consuming and require more effort for installation since the shielding mass would need to be transported to a support structure over the refueling pool. A preferable approach is to use the existing shielding mass of the refueling pool water. A method of shielding was devised which would use a vacuum pump to draw refueling pool water into an inverted canister suspended over the upper internals to provide shielding from the normally exposed components. During the Spring 1993 refueling of Indian Point 2 (IP2), a prototype shield device was demonstrated. This shield consists of a cylindrical tank open at the bottom that is suspended over the refueling pool with I-beams. The lower lip of the tank is two feet below normal pool level. After installation, the air width of the natural shielding provided by the existing pool water. This paper describes the design, development, testing and demonstration of the prototype device.

Transfusion strategy for acute upper gastrointestinal bleeding.

Science.gov (United States)

Handel, James; Lang, Eddy

2015-09-01

Clinical question Does a hemoglobin transfusion threshold of 70 g/L yield better patient outcomes than a threshold of 90 g/L in patients with acute upper gastrointestinal bleeding? Article chosen Villanueva C, Colomo A, Bosch A, et al. Transfusion strategies for acute upper gastrointestinal bleeding. N Engl J Med 2013;368(1):11-21. Study objectives The authors of this study measured mortality, from any cause, within the first 45 days, in patients with acute upper gastrointestinal bleeding, who were managed with a hemoglobin threshold for red cell transfusion of either 70 g/L or 90 g/L. The secondary outcome measures included rate of further bleeding and rate of adverse events.

Upper Eyelid Fractional CO2 Laser Resurfacing With Incisional Blepharoplasty.

Science.gov (United States)

Kotlus, Brett S; Schwarcz, Robert M; Nakra, Tanuj

2016-01-01

Laser resurfacing, performed at the same time as blepharoplasty, has most commonly been applied to the lower eyelid skin but can effectively be used on the upper eyelid to reduce rhytidosis and improve skin quality. The authors evaluate the safety and efficacy of this procedure. Fractional CO2 laser resurfacing was performed in conjunction with incisional upper blepharoplasty. The ultrapulsed laser energy was applied to the sub-brow skin, the upper medial canthal skin, and the pretarsal skin in 30 patients. Photos were obtained preoperatively and at 3 months. All patients demonstrated reduction in upper eyelid rhytidosis without any serious complications. Independent rhytidosis grading (0-4) showed a mean improvement of 42%. One patient experienced wound dehiscence that satisfactorily resolved without intervention. Upper eyelid laser resurfacing is effective and can be safely performed at the same time as upper blepharoplasty. This approach reduces or eliminates the need for medial incisions to address medial canthal skin redundancy and rhytidosis and it directly treats upper eyelid wrinkles on residual eyelid and infra-brow skin during blepharoplasty.

An exceptionally preserved transitional lungfish from the lower permian of Nebraska, USA, and the origin of modern lungfishes.

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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.

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

Upper urinary tract tumors

DEFF Research Database (Denmark)

Gandrup, Karen L; Nordling, Jørgen; Balslev, Ingegerd

2014-01-01

BACKGROUND: Computed tomography urography (CTU) is used widely in the work-up of patients with symptoms of urinary tract lesions. Preoperative knowledge of whether a tumor is invasive or non-invasive is important for the choice of surgery. So far there are no studies about the distinction...... of invasive and non-invasive tumors in ureter and renal pelvis based on the enhancement measured with Hounsfield Units. PURPOSE: To examine the value of CTU using split-bolus technique to distinguish non-invasive from invasive urothelial carcinomas in the upper urinary tract. MATERIAL AND METHODS: Patients...... obtained at CTU could distinguish between invasive and non-invasive lesions. No patients had a CTU within the last year before the examination that resulted in surgery. CONCLUSION: A split-bolus CTU cannot distinguish between invasive and non-invasive urothelial tumors in the upper urinary tract...

Work-Related Upper Limb Disorders: A Case Report

Directory of Open Access Journals (Sweden)

Zlatka Borisova Stoyneva

2015-03-01

Full Text Available In this study the complex interrelationship between physical factors, job stress, lifestyle and genetic factors on symptoms of work-related musculoskeletal disorders of the upper limbs is demonstrated by a case report and discussion of the literature. A 58 year old woman with long lasting complaints of the upper limbs with increasing intensity and duration, generalisation, combined with skin thickness, Raynaud’s phenomenon, joint disorders, arterial and pulmonary hypertension, metabolic lipid dysfunctions is presented. Occupational history proves continuous duration of service at a job with occupational physical static load with numerous repetitive monotonous systematic motions of fingers and hands as a weaver of Persian rugs followed by work at an automated loom and variable labour activities. Though the complaints dated since the time she was a manual weaver, the manifestations of generalized joint degenerative changes, system sclerosis with Raynaud’s phenomenon with similar upper extremities signs and symptoms discount upper limbs musculoskeletal disorder as caused only or mainly by occupational risk factors. The main principles and criteria for occupational diagnosis of musculoskeletal upper limb disorders and legislative requirements for their reglamentation are discussed.

Visceral pain originating from the upper urinary tract

DEFF Research Database (Denmark)

Pedersen, Katja Venborg; Drewes, Asbjørn Mohr; Frimodt-Møller, Poul Christian

2010-01-01

Pain originating from the upper urinary tract is a common problem and stone colic is one of the most intense pain conditions that can be experienced in the clinic. The pain is difficult to alleviate and often leads to medical attention. In humans, pain mechanisms of the upper urinary tract pain...... are still poorly understood, which often leads to a trial and error approach in clinical pain management. Pain from the upper urinary tract seems to have all the characteristics of pure visceral pain, including referred pain with or without hyperalgesia/trophic changes in somatic tissues and viscero......-visceral hyperalgesia. However, further studies are needed to better understand these visceral pain mechanisms with regard to optimising pain management. This review gives an introduction to visceral pain in general and upper urinary tract pain in particular, with special reference to pain pathways and pharmacological...

Upper limits on the total cosmic-ray luminosity of individual sources

Energy Technology Data Exchange (ETDEWEB)

Anjos, R.C.; De Souza, V. [Instituto de Física de São Carlos, Universidade de São Paulo, São Paulo (Brazil); Supanitsky, A.D., E-mail: rita@ifsc.usp.br, E-mail: vitor@ifsc.usp.br, E-mail: supanitsky@iafe.uba.ar [Instituto de Astronomía y Física del Espacio (IAFE), CONICET-UBA, Buenos Aires (Argentina)

2014-07-01

In this paper, upper limits on the total luminosity of ultra-high-energy cosmic-rays (UHECR) E > 10{sup 18} eV) are determined for five individual sources. The upper limit on the integral flux of GeV--TeV gamma-rays is used to extract the upper limit on the total UHECR luminosity of individual sources. The correlation between upper limit on the integral GeV--TeV gamma-ray flux and upper limit on the UHECR luminosity is established through the cascading process that takes place during propagation of the cosmic rays in the background radiation fields, as explained in reference [1]. Twenty-eight sources measured by FERMI-LAT, VERITAS and MAGIC observatories have been studied. The measured upper limit on the GeV--TeV gamma-ray flux is restrictive enough to allow the calculation of an upper limit on the total UHECR cosmic-ray luminosity of five sources. The upper limit on the UHECR cosmic-ray luminosity of these sources is shown for several assumptions on the emission mechanism. For all studied sources an upper limit on the ultra-high-energy proton luminosity is also set.

Upper limits on the total cosmic-ray luminosity of individual sources

International Nuclear Information System (INIS)

Anjos, R.C.; De Souza, V.; Supanitsky, A.D.

2014-01-01

In this paper, upper limits on the total luminosity of ultra-high-energy cosmic-rays (UHECR) E > 10 18 eV) are determined for five individual sources. The upper limit on the integral flux of GeV--TeV gamma-rays is used to extract the upper limit on the total UHECR luminosity of individual sources. The correlation between upper limit on the integral GeV--TeV gamma-ray flux and upper limit on the UHECR luminosity is established through the cascading process that takes place during propagation of the cosmic rays in the background radiation fields, as explained in reference [1]. Twenty-eight sources measured by FERMI-LAT, VERITAS and MAGIC observatories have been studied. The measured upper limit on the GeV--TeV gamma-ray flux is restrictive enough to allow the calculation of an upper limit on the total UHECR cosmic-ray luminosity of five sources. The upper limit on the UHECR cosmic-ray luminosity of these sources is shown for several assumptions on the emission mechanism. For all studied sources an upper limit on the ultra-high-energy proton luminosity is also set

Evaluation of postoperative patient satisfaction after covering the nasal dorsum with upper lateral cartilage: "upper lateral closing".

Science.gov (United States)

Çağıcı, Can Alper

2017-11-16

Following nasal hump removal during septorhinoplasty, the middle vault should be reconstructed to avoid functional and esthetic problems. Middle vault reconstruction, however, may result in widening of the middle vault and may need a camouflage graft to cover dorsal irregularities. To present the results of reconstructing the middle vault with a technique that covers the nasal dorsum with upper lateral cartilage, from the viewpoint of patient satisfaction. Retrospective study of patients who underwent septorhinoplasty that included nasal dorsum closure with upper lateral cartilage from December 1, 2014 to January 31, 2016. Those with postoperative follow-up of less than 3 months were excluded. The final study group included 39 patients. The same surgeon performed all septorhinoplasties. The dorsum was closed using an "upper lateral closing" technique that approximated upper lateral cartilages to each other over the septum. Postoperative patient satisfaction was determined using a visual analog scale and the rhinoplasty outcomes evaluation questionnaire. The questionnaire evaluates patient esthetic and functional satisfaction with the operated nose. High scores indicate improved esthetic results. No dorsal irregularities were seen at postoperative follow-up evaluation of the patients. For esthetic nasal appearance, the median visual analogue scale scores was 86%, and the mean for the questionnaire was 77.03%. The natural dome-shaped anatomy of the nasal dorsum was achieved by approximating the upper lateral cartilages to each other. Closing the dorsum with this technique also covers any dorsal irregularities and results in a smooth dorsum. Patients expressed satisfaction with the esthetic and functional aspects of the smooth, attractive nasal dorsum. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Upper intestinal lipids regulate energy and glucose homeostasis.

Science.gov (United States)

Cheung, Grace W C; Kokorovic, Andrea; Lam, Tony K T

2009-09-01

Upon the entry of nutrients into the small intestine, nutrient sensing mechanisms are activated to allow the body to adapt appropriately to the incoming nutrients. To date, mounting evidence points to the existence of an upper intestinal lipid-induced gut-brain neuronal axis to regulate energy homeostasis. Moreover, a recent discovery has also revealed an upper intestinal lipid-induced gut-brain-liver neuronal axis involved in the regulation of glucose homeostasis. In this mini-review, we will focus on the mechanisms underlying the activation of these respective neuronal axes by upper intestinal lipids.

Upper Gastrointestinal Symptoms Predictive of Candida Esophagitis and Erosive Esophagitis in HIV and Non-HIV Patients

Science.gov (United States)

Takahashi, Yuta; Nagata, Naoyoshi; Shimbo, Takuro; Nishijima, Takeshi; Watanabe, Koji; Aoki, Tomonori; Sekine, Katsunori; Okubo, Hidetaka; Watanabe, Kazuhiro; Sakurai, Toshiyuki; Yokoi, Chizu; Mimori, Akio; Oka, Shinichi; Uemura, Naomi; Akiyama, Junichi

2015-01-01

Abstract Upper gastrointestinal (GI) symptoms are common in both HIV and non-HIV-infected patients, but the difference of GI symptom severity between 2 groups remains unknown. Candida esophagitis and erosive esophagitis, 2 major types of esophagitis, are seen in both HIV and non-HIV-infected patients, but differences in GI symptoms that are predictive of esophagitis between 2 groups remain unknown. We aimed to determine whether GI symptoms differ between HIV-infected and non-HIV-infected patients, and identify specific symptoms of candida esophagitis and erosive esophagitis between 2 groups. We prospectively enrolled 6011 patients (HIV, 430; non-HIV, 5581) who underwent endoscopy and completed questionnaires. Nine upper GI symptoms (epigastric pain, heartburn, acid regurgitation, hunger cramps, nausea, early satiety, belching, dysphagia, and odynophagia) were evaluated using a 7-point Likert scale. Associations between esophagitis and symptoms were analyzed by the multivariate logistic regression model adjusted for age, sex, and proton pump inhibitors. Endoscopy revealed GI-organic diseases in 33.4% (2010/6.011) of patients. The prevalence of candida esophagitis and erosive esophagitis was 11.2% and 12.1% in HIV-infected patients, respectively, whereas it was 2.9% and 10.7 % in non-HIV-infected patients, respectively. After excluding GI-organic diseases, HIV-infected patients had significantly (P symptom scores for heartburn, hunger cramps, nausea, early satiety, belching, dysphagia, and odynophagia than non-HIV-infected patients. In HIV-infected patients, any symptom was not significantly associated with CD4 cell count. In multivariate analysis, none of the 9 GI symptoms were associated with candida esophagitis in HIV-infected patients, whereas dysphagia and odynophagia were independently (P HIV-infected patients. However, heartburn and acid regurgitation were independently (P symptom scores were reliable in both HIV (α, 0.86) and non-HIV-infected patients

Structural-functional organization of the littoral zooplankton communities of the Kremenchutskiy reservoir

Directory of Open Access Journals (Sweden)

Z. Burian

2018-03-01

Full Text Available Purpose. To find out the present state of the structural and functional organization of the littoral zooplankton communities of the upper Kremenchuk reservoir in the area of ​​the Kaniv Nature Reserve. Methodology. The material was collected in the summer time of 2016 at six stations of the littoral zone of the upper Kremenchug reservoir. The collection and analysis were carried out using generally accepted methods. The objects of the research were representatives of three main groups of zooplankton (rotifers, cladocerans, copepods, as well as ostracods and larvae of bivalve molluscs. Statistical data processing was done in MS Excel 2013. Findings. The results of the study represent the present state and organisation of littoral zooplankton. The species richness of the littoral zooplankton of the upper Kremenchug reservoir was presented by 48 species. There are 20 species of monogonont rotifers, 18 cladocerans species and copepods – 10. The representatives of the rotifer-cladoceran complex dominated in the taxonomic composition that can be explained by the preservation of the river regime and the rheophilic conditions in this part of the reservoir. The analysis showed that according to the ecological spectrum of zooplankton groups, the representatives of the pelagic group dominated – 47.92%. As for the feeding type, the largest share was represented by the non-predatory group – 64.58%. After analyzing of the quantitative indices (density and biomass of zooplankton, it was found that they were lower than average for overgrown biotopes (112580 ± 129914 ind./m³ і 1.83 ± 2.07 g/m³ and low for open water (26160 ± 19161 ind./m³ і 0,82 ± 0,86 g/m³. Originality. The present state of structural and functional organization of the littoral zooplankton communities of the upper Kremenchug reservoir has been revealed. Practical significance. The conducted studies give the information about the structural and functional organization of the

Preliminary stratigraphy and facies analysis of the Upper Cretaceous Kaguyak Formation, including a brief summary of newly discovered oil stain, upper Alaska Peninsula

Science.gov (United States)

Wartes, Marwan A.; Decker, Paul L.; Stanley, Richard G.; Herriott, Trystan M.; Helmold, Kenneth P.; Gillis, Robert J.

2013-01-01

The Alaska Division of Geological and Geophysical Surveys has an ongoing program aimed at evaluating the Mesozoic forearc stratigraphy, structure, and petroleum systems of lower Cook Inlet. Most of our field studies have focused on the Jurassic component of the petroleum system (this report). However, in late July and early August of 2012, we initiated a study of the stratigraphy and reservoir potential of the Upper Cretaceous Kaguyak Formation. The Kaguyak Formation is locally well exposed on the upper Alaska Peninsula (fig. 25) and was named by Keller and Reiser (1959) for a sequence of interbedded siltstone and sandstone of upper Campanian to Maastrichtian age that they estimated to be 1,450 m thick.Subsequent work by Detterman and Miller (1985) examined 900 m of section and interpreted the unit as the record of a prograding submarine fan.This interpretation of deep-water deposition contrasts with other Upper Cretaceous rocks exposed along the Alaska Peninsula and lower Cook Inlet that are generally described as nonmarine to shallow marine (Detterman and others, 1996; LePain and others, 2012).Based on foraminifera and palynomorphs from the COST No. 1 well, Magoon (1986) concluded that the Upper Cretaceous rocks were deposited in a variety of water depths and environments ranging from upper bathyal to nonmarine. During our recent fieldwork west and south of Fourpeaked Mountain, we similarly encountered markedly varying lithofacies in the Kaguyak Formation (fig. 25), and we also found oil-stained rocks that are consistent with the existence of an active petroleum system in Upper Cretaceous rocks on the upper Alaska Peninsula and in lower Cook Inlet. These field observations are summarized below.

Infantile lipofibromatosis of the upper limb

Energy Technology Data Exchange (ETDEWEB)

Teo, Harvey E.L.; Peh, Wilfred C.G. [KK Women' s and Children' s Hospital, Department of Diagnostic Imaging, Singapore (Singapore); Chan, Mei-Yoke [KK Women' s and Children' s Hospital, Department of Paediatric Medicine, Singapore (Singapore); Walford, Norman [Tan Tock Seng Hospital, Department of Pathology, Singapore (Singapore)

2005-12-01

The imaging features of extensive lipofibromatosis presenting in a 1-day-old female infant are reported. This lesion involved her entire right upper limb, extending from the axilla to the palm of the hand. Radiographs showed marked deformity and thinning of all the right upper-limb bones due to pressure effect of soft-tissue enlargement, especially affecting the distal humerus and proximal forearm bones. Magnetic resonance imaging showed a huge soft-tissue mass infiltrating most of the muscles of the entire upper limb, with bony erosion. The mass was largely T1-isointense, moderately T2-hyperintense and showed marked enhancement. There were intra-lesional signal changes consistent with fatty elements. A lesion debulking procedure was performed and the histology was that of lipofibromatosis. The limb was found to be non-viable after the procedure and a subsequent above-elbow amputation was performed. Although the resection margins were not clear, she had no further recurrence over a subsequent 3-year follow-up period. (orig.)

Restoration of Prime Farmland Disturbed by Mineral Sand Mining in the Upper Coastal Plain of Virginia

OpenAIRE

Schroeder, Philip D.

1996-01-01

Economic deposits of heavy mineral sand were identified in the late 1980's under prime farmland along the Upper Coastal Plain of Virginia. Mining in Virginia will commence in 1997 on the Old Hickory Deposit in Dinwiddie/Sussex Counties. Experiments were established on two mine pits representing two likely pit closure scenarios; regrading the surface with unprocessed subsoil (Pit 1) or filling to the surface with processed material (Pit 3). To evaluate topsoil replacement vs. organic amendment...

The gothic arch tracing and the upper canine teeth as guides in the positioning of upper posterior teeth.

Science.gov (United States)

el-Gheriani, A S; Davies, A L; Winstanley, R B

1989-09-01

The relationship between the position of the buccal cusps of the natural upper posterior teeth and the distance between the lateral arms of the Gothic arch tracing or the distance between the upper canine teeth has been found to be constant to within +/- 2 mm. This may be of value when setting up artificial teeth for denture patients, enabling them to be positioned close to the natural predecessors.

Upper entropy axioms and lower entropy axioms

International Nuclear Information System (INIS)

Guo, Jin-Li; Suo, Qi

2015-01-01

The paper suggests the concepts of an upper entropy and a lower entropy. We propose a new axiomatic definition, namely, upper entropy axioms, inspired by axioms of metric spaces, and also formulate lower entropy axioms. We also develop weak upper entropy axioms and weak lower entropy axioms. Their conditions are weaker than those of Shannon–Khinchin axioms and Tsallis axioms, while these conditions are stronger than those of the axiomatics based on the first three Shannon–Khinchin axioms. The subadditivity and strong subadditivity of entropy are obtained in the new axiomatics. Tsallis statistics is a special case of satisfying our axioms. Moreover, different forms of information measures, such as Shannon entropy, Daroczy entropy, Tsallis entropy and other entropies, can be unified under the same axiomatics

Robot-Aided Upper-Limb Rehabilitation Based on Motor Imagery EEG

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Baoguo Xu

2011-09-01

Full Text Available Stroke is a leading cause of disability worldwide. In this paper, a novel robot-assisted rehabilitation system based on motor imagery electroencephalography (EEG is developed for regular training of neurological rehabilitation for upper limb stroke patients. Firstly, three-dimensional animation was used to guide the patient image the upper limb movement and EEG signals were acquired by EEG amplifier. Secondly, eigenvectors were extracted by harmonic wavelet transform (HWT and linear discriminant analysis (LDA classifier was utilized to classify the pattern of the left and right upper limb motor imagery EEG signals. Finally, PC triggered the upper limb rehabilitation robot to perform motor therapy and gave the virtual feedback. Using this robot-assisted upper limb rehabilitation system, the patient's EEG of upper limb movement imagination is translated to control rehabilitation robot directly. Consequently, the proposed rehabilitation system can fully explore the patient's motivation and attention and directly facilitate upper limb post-stroke rehabilitation therapy. Experimental results on unimpaired participants were presented to demonstrate the feasibility of the rehabilitation system. Combining robot-assisted training with motor imagery-based BCI will make future rehabilitation therapy more effective. Clinical testing is still required for further proving this assumption.

Marine organisms and their adaption - Adaptions solve the challenges of existence in the sea.

Digital Repository Service at National Institute of Oceanography (India)

Gonsalves, M.J.B.D.; Das, A.; LokaBharathi, P.A.

in the upper ocean; the size of marine organisms decrease with depth (1) Marine adption includes symbiosis, camouflage, size, contact, communication, defensive and reproductive strategies besides, adaptions to environmental conditions like temperature, light...

Accounting for External Turbulence of Logistics Organizations via Performance Measurement Systems

DEFF Research Database (Denmark)

Bühler, Andreas; Wallenburg, Carl Marcus; Wieland, Andreas

2016-01-01

Purpose: This paper aims to investigate the role of upper management in designing performance measurement systems (PMS) that account for external turbulence of the organization and to show how this PMS design for turbulence impacts organizational resilience and distribution service performance....... Design/methodology/approach: Hypotheses are developed by integrating management accounting and strategic management perspectives into supply chain management and subsequently tested based on data from 431 logistics organizations (i.e. both logistics companies and internal logistics departments...

Traumatic upper cervical esophageal perforation in childhood with ...

African Journals Online (AJOL)

rae. The next step was an upper gastrointestinal series, in which posterior oropharyngeal and cervical esophageal perforation draining to the posterior mediastinum was detected (Fig. 1). Emergency laryngobronchoscopy and esophagoscopy were performed. The upper and lower airways were normal except mild laryngeal ...

A dichotomy for upper domination in monogenic classes

KAUST Repository

AbouEisha, Hassan M.; Hussain, Shahid; Lozin, Vadim V.; Monnot, Jé rô me; Ries, Bernard

2014-01-01

An upper dominating set in a graph is a minimal (with respect to set inclusion) dominating set of maximum cardinality. The problem of finding an upper dominating set is NP-hard for general graphs and in many restricted graph families. In the present

Upper plenum dump during reflood in PWR loss-of-coolant accident

International Nuclear Information System (INIS)

Sudo, Yukio; Griffith, Peter.

1981-01-01

Upper plenum dump during reflood in a large break loww-of-coolant accident of PWR is studied with the emergency core coolant injection into the upper plenum in addition to the cold leg. Transient experiments were carried out by injecting water into the upper plenum and the simple analysis based on a one-dimensional model was done using the drift flux model in order to investigate the conditions under which water dump through the core occurs during reflood. The most significant result is an upper plenum dump occurs when the pressure (hydrostatic head) in the upper plenum is greater than that in the lower plenum. Under those circumstances the flow regime isco-current down flow in which the upper plenum is rapidly emptied. On the other hand, when the upper plenum pressure (hydrostatic head) is less than the lower plenum pressure (hydrostatic head), the co-current down flow is not realized but a counter-current flow occurs. With subcooled water injection to the upper plenum, co-current down flow is realized even when the upper plenum hydrostatic head is less than the lower plenum hydrostatic head. The importance of this effect varies according to the magnetude of water subcooling. (author)

Devonian granitoids and their hosted mafic enclaves in the Gorny Altai terrane, northwestern Central Asian Orogenic Belt: crust-mantle interaction in a continental arc setting

Science.gov (United States)

Chen, Ming; Sun, Min

2016-04-01

Granitoids are a major component in the upper continental crust and hold key information on how did the continental crust grow and differentiate. This study focuses on the Yaloman intrusive complex from the Gorny Altai terrane, northwestern Central Asian Orogenic Belt (CAOB). The association of granitoids and mafic enclaves can provide important clues on the source nature, petrogenetic processes and geodynamic setting of the Yaloman intrusive complex, which in turn will shed light on the crustal evolution in the northwestern CAOB. Zircon U-Pb dating shows that the granitoids, including quartz diorites and granodiorites, were emplaced in ca. 389-387 Ma. The moderate Na2O + K2O contents and low A/CNK values indicate that these rocks belong to the sub-alkaline series with metaluminous to weakly peraluminous compositions. The granitoids yield two-stage zircon Hf model ages of ca. 0.79-1.07 Ga and whole-rock Nd model ages of ca. 0.90-0.99 Ga, respectively, implying that they were mainly sourced from Neoproterozoic juvenile crustal materials. The mafic enclaves show an almost identical crystallization age of ca. 389 Ma. The identification of coarse-grained xenocrysts and acicular apatites, together with the fine-grained texture, makes us infer that these enclaves are likely to represent magmatic globules commingled with the host magmas. The low SiO2 and high MgO contents of the mafic enclaves further suggest that substantial mantle-derived mafic melts were probably involved in their formation. Importantly, the SiO2 contents of the granitoids and mafic enclaves are well correlated with other major elements and most of the trace elements. Also a broadly negative correlation exists between the SiO2 contents and whole-rock epsilon Nd (390 Ma) values of the granitoids. Given the observation of reversely zoned plagioclases within the granitoids and the common occurrence of igneous mafic enclaves, we propose that magma mixing probably played an important role in the formation

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)

Bedded Barite Deposits from Sonora (nw Mexico): a Paleozoic Analog for Modern Cold Seeps

Science.gov (United States)

Canet, C.; Anadón, P.; González-Partida, E.; Alfonso, P.; Rajabi, A.; Pérez-Segura, E.; Alba-Aldave, L. A.

2013-05-01

The Mazatán barite deposits represent an outstanding example of Paleozoic bedded barite, a poorly understood type of mineral deposit of major economic interest. The largest barite bodies of Mazatán are hosted within an Upper Carboniferous flysch succession, which formed part of an accretionary wedge related to the subduction of the Rheic Ocean beneath Gondwana. As well, a few barite occurrences are hosted in Upper Devonian, pre-orogenic turbidites. A variety of mineralized structures is displayed by barite, including: septaria nodules, enterolitic structures, rosettes and debris-flow conglomerates. Barite is accompanied by chalcedony, pyrite (framboids) and berthierine. Gas-rich fluid inclusions in barite were analyzed by Raman spectroscopy and methane was identified, suggesting the occurrence of light hydrocarbons in the environment within which barite precipitated. 13C-depleted carbonates (δ13C: -24.3 to -18.8‰) were found in the barite deposits; they formed through anaerobic oxidation of methane coupled to sulfate reduction, and yield negative δ18O values (-11.9 to -5.2‰) reflecting the isotopic composition of Devonian-Carboniferous seawater. Methane-derived carbonates occur in modern hydrocarbon seeps and have been reported from Mesozoic and Cenozoic seep sediments, but they have never before been described in Paleozoic bedded barite deposits. δ34S of barite varies from +17.6 to +64.1‰, with the lowest values overlapping the range for coeval seawater sulfate; this distribution indicates a process of sulfate reduction. Barite precipitation can be explained by mixing of methane- and barium-rich fluids with pore-water (seawater) containing sulfate residual from microbial reduction. Two analyses from barite gave an 87Sr/86Sr within and slightly above the range for seawater at the time of deposition, with 0.708130 and 0.708588, which would preclude the involvement of hydrothermal fluids in the mineralization process.

Cerebral gas embolism due to upper gastrointestinal endoscopy

NARCIS (Netherlands)

ter Laan, Mark; Totte, Erik; van Hulst, Rob A.; van der Linde, Klaas; van der Kamp, Wim; Pierie, Jean-Pierre E.

Cerebral gas embolism as a result of upper gastrointestinal endoscopy is a rare complication and bares a high morbidity. A patient is presented who underwent an upper endoscopy for evaluation of a gastric-mediastinal fistula after subtotal oesophagectomy and gastric tube reconstruction because of

Cerebral gas embolism due to upper gastrointestinal endoscopy

NARCIS (Netherlands)

ter Laan, Mark; Totte, Erik; van Hulst, Rob A.; van der Linde, Klaas; van der Kamp, Wim; Pierie, Jean-Pierre E.

2009-01-01

Cerebral gas embolism as a result of upper gastrointestinal endoscopy is a rare complication and bares a high morbidity. A patient is presented who underwent an upper endoscopy for evaluation of a gastric-mediastinal fistula after subtotal oesophagectomy and gastric tube reconstruction because of

Upper limb injury in rugby union football: results of a cohort study.

Science.gov (United States)

Usman, Juliana; McIntosh, Andrew Stuart

2013-04-01

There have been few in-depth studies of upper limb injury epidemiology in rugby union football, despite reports that they accounted for between 14% and 28% of all rugby injuries. To report on upper limb injury incidence, injury severity and to identify the risk factors associated with upper limb injuries, for example, level of play, season (years) and playing position. Prospective cohort study across five rugby seasons from 2004 to 2008. Formal rugby competitions-suburban, provincial and international. 1475 adult male rugby players in Colts, Grade and Elite competitions. An upper limb injury resulting in a missed game and its characteristics. A total of 61 598 athletic exposures (AE) and 606 upper limb injuries were recorded. About 66% of the injuries were to the shoulder. The overall upper limb injury incidence rate (IIR) was 9.84 injuries/1000 AE (95% CI 9.06 to 10.62). Statistically significant associations were found between upper limb injuries and level of play; and between shoulder injuries and playing position (p<0.05). No association was found between upper limb and shoulder injuries and study year. The overall upper limb IIR decreased as the level of play increased; 10.74 upper limb injuries/1000 AE (95% CI 9.93 to 11.56) in Colts to 6.07 upper limb injuries/1000 AE (95% CI 5.46 to 6.69) in Elite. The upper limb IIR decreased as the level of play increased indicating that age, level of skill and playing experience may be risk factors for upper limb injury.

Upper Domination: Towards a Dichotomy Through Boundary Properties

KAUST Repository

AbouEisha, Hassan M.

2017-07-14

An upper dominating set in a graph is a minimal dominating set of maximum cardinality. The problem of finding an upper dominating set is generally NP-hard. We study the complexity of this problem in finitely defined classes of graphs and conjecture that the problem admits a complexity dichotomy in this family. A helpful tool to study the complexity of an algorithmic problem is the notion of boundary classes. However, none of such classes has been identified so far for the upper dominating set problem. We discover the first boundary class for this problem and prove the dichotomy for monogenic classes.

Congenital upper eyelids ectropion in Down’s syndrome

Directory of Open Access Journals (Sweden)

Corredor-Osorio, Rafael

2017-02-01

Full Text Available Congenital bilateral ectropion of the upper eyelids is a rare, benign condition reported in ophthalmic literature. It is more frequently associated with Down’s syndrome, ichthyosis, and sporadic cases in newborns from black population. We report three cases of congenital bilateral upper eyelid ectropion associated with Down’s syndrome. Management of these patients usually requires medial and lateral canthoplasties, full-thickness pentagonal resection of the upper eyelids and placement of skin grafts. We present herein the evolution of one of these patients and we will discuss the mechanism of the eyelid ectropion and its treatment.

Prevalence of upper limb disorders among female librarians.

Science.gov (United States)

Pandy, R

2013-09-01

Work as a librarian involves exposure to potential risk factors for developing upper limb disorders. The prevalence of upper limb symptoms has, however, not previously been assessed in this occupational group. To estimate the 7-day and annual prevalence of self-reported neck and upper limb symptoms in librarians and to examine associations with specific tasks and ergonomic risk factors. A cross-sectional study using components of the standardized Nordic questionnaire. The study population consisted of librarians employed by a large local authority, and data collection was by means of a self-administered questionnaire. from studies on keyboard workers and on the general population were used as comparators. The 7-day prevalence of self-reported neck and upper limb pain in female librarians was 42% (95% confidence interval (CI) 33.7-50.5) and the annual prevalence was 65% (95% CI 56.6-72.8). The prevalence of reported wrist and hand pain increased with increased working involving a wide thumb-index span (P librarians was high, but there was insufficient evidence to confirm whether the prevalence was higher than in the general population or among keyboard workers. Working with a wide thumb-index span was associated with reporting upper limb symptoms.

in upper gastrointestinal endoscopy

Directory of Open Access Journals (Sweden)

Sinan Uzman

2016-07-01

Full Text Available Introduction : There is increasing interest in sedation for upper gastrointestinal endoscopy (UGE. Prospective randomized studies comparing sedation properties and complications of propofol and midazolam/meperidine in upper gastrointestinal endoscopy (UGE are few. Aim: To compare propofol and midazolam/meperidine sedation for UGE in terms of cardiopulmonary side effects, patient and endoscopist satisfaction and procedure-related times. Material and methods: This was a prospective, randomized, double-blind study of propofol versus midazolam and meperidine in 100 patients scheduled for diagnostic upper gastrointestinal endoscopy. The patients were divided into propofol and midazolam/meperidine groups. Randomization was generated by a computer. Cardiopulmonary side effects (hypotension, bradycardia, hypoxemia, procedure-related times (endoscopy time, awake time, time to hospital discharge, and patient and endoscopist satisfaction were compared between groups. Results: There was no significant difference between the groups with respect to the cost, endoscopy time, or demographic and clinical characteristics of the patients. Awake time and time to hospital discharge were significantly shorter in the propofol group (6.58 ±4.72 vs. 9.32 ±4.26 min, p = 0.030 and 27.60 ±7.88 vs. 32.00 ±10.54 min, p = 0.019. Hypotension incidence was significantly higher in the propofol group (12% vs. 0%, p = 0.027. The patient and endoscopist satisfaction was better with propofol. Conclusions : Propofol may be preferred to midazolam/meperidine sedation, with a shorter awake and hospital discharge time and better patient and endoscopist satisfaction. However, hypotension risk should be considered with propofol, and careful evaluation is needed, particularly in cardiopulmonary disorders.

Development of a prognostic nomogram for cirrhotic patients with upper gastrointestinal bleeding.

Science.gov (United States)

Zhou, Yu-Jie; Zheng, Ji-Na; Zhou, Yi-Fan; Han, Yi-Jing; Zou, Tian-Tian; Liu, Wen-Yue; Braddock, Martin; Shi, Ke-Qing; Wang, Xiao-Dong; Zheng, Ming-Hua

2017-10-01

Upper gastrointestinal bleeding (UGIB) is a complication with a high mortality rate in critically ill patients presenting with cirrhosis. Today, there exist few accurate scoring models specifically designed for mortality risk assessment in critically ill cirrhotic patients with upper gastrointestinal bleeding (CICGIB). Our aim was to develop and evaluate a novel nomogram-based model specific for CICGIB. Overall, 540 consecutive CICGIB patients were enrolled. On the basis of Cox regression analyses, the nomogram was constructed to estimate the probability of 30-day, 90-day, 270-day, and 1-year survival. An upper gastrointestinal bleeding-chronic liver failure-sequential organ failure assessment (UGIB-CLIF-SOFA) score was derived from the nomogram. Performance assessment and internal validation of the model were performed using Harrell's concordance index (C-index), calibration plot, and bootstrap sample procedures. UGIB-CLIF-SOFA was also compared with other prognostic models, such as CLIF-SOFA and model for end-stage liver disease, using C-indices. Eight independent factors derived from Cox analysis (including bilirubin, creatinine, international normalized ratio, sodium, albumin, mean artery pressure, vasopressin used, and hematocrit decrease>10%) were assembled into the nomogram and the UGIB-CLIF-SOFA score. The calibration plots showed optimal agreement between nomogram prediction and actual observation. The C-index of the nomogram using bootstrap (0.729; 95% confidence interval: 0.689-0.766) was higher than that of the other models for predicting survival of CICGIB. We have developed and internally validated a novel nomogram and an easy-to-use scoring system that accurately predicts the mortality probability of CICGIB on the basis of eight easy-to-obtain parameters. External validation is now warranted in future clinical studies.

Orthodontic intervention of an impacted upper left central incisor due ...

African Journals Online (AJOL)

A fixed orthodontic appliance was used to facilitate traction and correction of malalignement of the impacted upper left central incisor.Treatment outcome: Successful removal of the odontoma, full exposure of the crown of upper left central incisor and good alignment on the arch were achieved. Crowding on the upper and ...

A mechanistic model of an upper bound on oceanic carbon export as a function of mixed layer depth and temperature

Directory of Open Access Journals (Sweden)

Z. Li

2017-11-01

Full Text Available Export production reflects the amount of organic matter transferred from the ocean surface to depth through biological processes. This export is in large part controlled by nutrient and light availability, which are conditioned by mixed layer depth (MLD. In this study, building on Sverdrup's critical depth hypothesis, we derive a mechanistic model of an upper bound on carbon export based on the metabolic balance between photosynthesis and respiration as a function of MLD and temperature. We find that the upper bound is a positively skewed bell-shaped function of MLD. Specifically, the upper bound increases with deepening mixed layers down to a critical depth, beyond which a long tail of decreasing carbon export is associated with increasing heterotrophic activity and decreasing light availability. We also show that in cold regions the upper bound on carbon export decreases with increasing temperature when mixed layers are deep, but increases with temperature when mixed layers are shallow. A meta-analysis shows that our model envelopes field estimates of carbon export from the mixed layer. When compared to satellite export production estimates, our model indicates that export production in some regions of the Southern Ocean, particularly the subantarctic zone, is likely limited by light for a significant portion of the growing season.

Improved Mars Upper Atmosphere Climatology

Science.gov (United States)

Bougher, S. W.

2004-01-01

The detailed characterization of the Mars upper atmosphere is important for future Mars aerobraking activities. Solar cycle, seasonal, and dust trends (climate) as well as planetary wave activity (weather) are crucial to quantify in order to improve our ability to reasonably depict the state of the Mars upper atmosphere over time. To date, our best information is found in the Mars Global Surveyor (MGS) Accelerometer (ACC) database collected during Phase 1 (Ls = 184 - 300; F10.7 = 70 - 90) and Phase 2 (Ls = 30 - 90; F10.7 = 90 - 150) of aerobraking. This database (100 - 170 km) consists of thermospheric densities, temperatures, and scale heights, providing our best constraints for exercising the coupled Mars General Circulation Model (MGCM) and the Mars Thermospheric General Circulation Model (MTGCM). The Planetary Data System (PDS) contains level 0 and 2 MGS Accelerometer data, corresponding to atmospheric densities along the orbit track. Level 3 products (densities, temperatures, and scale heights at constant altitudes) are also available in the PDS. These datasets provide the primary model constraints for the new MGCM-MTGCM simulations summarized in this report. Our strategy for improving the characterization of the Mars upper atmospheres using these models has been three-fold : (a) to conduct data-model comparisons using the latest MGS data covering limited climatic and weather conditions at Mars, (b) to upgrade the 15-micron cooling and near-IR heating rates in the MGCM and MTGCM codes for ad- dressing climatic variations (solar cycle and seasonal) important in linking the lower and upper atmospheres (including migrating tides), and (c) to exercise the detailed coupled MGCM and MTGCM codes to capture and diagnose the planetary wave (migrating plus non-migrating tidal) features throughout the Mars year. Products from this new suite of MGCM-MTGCM coupled simulations are being used to improve our predictions of the structure of the Mars upper atmosphere for the

7 CFR 1030.2 - Upper Midwest marketing area.

Science.gov (United States)

2010-01-01

... 7 Agriculture 9 2010-01-01 2009-01-01 true Upper Midwest marketing area. 1030.2 Section 1030.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE UPPER MIDWEST MARKETING AREA Order...

Work-related upper limb “overuse” syndromes

DEFF Research Database (Denmark)

Jepsen, Jørgen Riis

2016-01-01

A previous review of historical descriptions and theories about the character and pathogenesis of writer’s cramp and other comparable chronic upper limb “overuse” work-related pain syndromes has indicated that somatic dysfunctions explain symptoms and findings. The first case studies and case...... series suggested that these conditions were caused by pathology affecting the peripheral nerves. The general perception gradually changed, however, with symptoms becoming attributed to central nervous system dysfunction and ultimately to represent a psychiatric condition. Work-related upper limb...... disorders remain diagnostically challenging to clinicians and there is still a tendency to see many patients’ pain as a psychiatric problem when a standard physical examination does not explain the condition. This article describes reports of writer’s cramp and comparable occupational upper limb “overuse...

Upper limb treatment technigues for stroke survivors

Directory of Open Access Journals (Sweden)

Martyna Kornet

2017-03-01

It was considered that the most important elements of the treatment used in the rehabilitation of the paretic upper limb are: exercise matching the anti-spasm pattern, maintaining appropriate position for exercise that provide an approximation of the shoulder joint and the use of cross-facilitation. The study indicates that the treatment of a post stroke upper limb should be based on the: physiotherapy, kinesiotherapy and specific positioning - all of them corresponding to a given stage of the disease. The work also presents the most frequently used methods, especially highlighting: the Prorioceptive Neuromuscular Facilitation (PNF, Bobath, Brunnstrom, CIMT and OIT. It was also shown that in order to enhance the effects of a post-stroke upper limb rehabilitation, it should be extended by modern methods such as Mirror Therapy, Virtual Reality or Robot-assisted Therapy.

Percutaneous transsplenic varices embolization for upper gastrointestinal bleeding

International Nuclear Information System (INIS)

Zhang Qiang; Li Jingyu; Lu Junliang; Xu Liyang; Liu Tao

2010-01-01

Objective: To investigate the value of percutaneous transsplenic varices embolization (PTSVE) for treatment of upper gastrointestinal bleeding. Methods: Twenty cases with liver cirrhosis and portal hypertension suffered upper gastrointestinal bleeding. PTSVE was administered to them with hardener and coils. Among them, 8 cases had massive hepatocellular carcinoma (HCC) in right lobe; 10 cases with hepatocellular carcinoma had portal vein tumor thrombus and occlusion; the other two cases with liver cirrhosis had portal vein thrombosis. All of these cases were not suitable for percutaneous transhepatic varices embolization (PTHVE). PTSVE was performed under the guidance of fluoroscopy. Results: Technical success was achieved in 18 patients. A total of 35 gastric coronary veins were embolized. In all these cases, upper gastrointestinal bleeding stopped after PTSVE. There was no recurrence within 1 month follow-up. No serious complication occurred. Conclusion: PTSVE is a safe and efficient alternative treatment for upper gastrointestinal bleeding, especially for cases with portal vein occlusion or with massive HCC in right lobe of liver. (authors)

Comparison of upper arm and forearm blood pressure.

Science.gov (United States)

Domiano, Kathy L; Hinck, Susan M; Savinske, Debra L; Hope, Kathryn L

2008-11-01

The upper arm is the primary site used to obtain a blood pressure measurement (BPM); however, when it is not possible to use the upper arm, the forearm is a commonly used alternate site. This study determines if there is a significant difference between upper arm and forearm BPMs among adults and examines the relationship of participant characteristics to the BPM difference. A convenience sample was recruited from a low-income, independent-living, 104-apartment complex in the Midwest. Of the 106 participants, 64% were female and 89% were White. Ages ranged from 20 to 85 years (M = 50.7). The investigators calculated the BMIs (range = 18 to 42, M = 29.3, SD = 5.4) for the 89% (n = 94) of participants who reported their weight. The forearm tended to have higher BPMs than the upper arm (M difference = 4.0 mm Hg systolic, 2.3 mm Hg diastolic). However, site differences were greatest for men, obese adults, and middle aged (36 to 65) adults.

Robot-Aided Upper-Limb Rehabilitation Based on Motor Imagery EEG

Directory of Open Access Journals (Sweden)

Baoguo Xu

2011-09-01

Full Text Available Stroke is a leading cause of disability worldwide. In this paper, a novel robot‐assisted rehabilitation system based on motor imagery electroencephalography (EEG is developed for regular training of neurological rehabilitation for upper limb stroke patients. Firstly, three‐dimensional animation was used to guide the patient image the upper limb movement and EEG signals were acquired by EEG amplifier. Secondly, eigenvectors were extracted by harmonic wavelet transform (HWT and linear discriminant analysis (LDA classifier was utilized to classify the pattern of the left and right upper limb motor imagery EEG signals. Finally, PC triggered the upper limb rehabilitation robot to perform motor therapy and gave the virtual feedback. Using this robot‐assisted upper limb rehabilitation system, the patientʹs EEG of upper limb movement imagination is translated to control rehabilitation robot directly. Consequently, the proposed rehabilitation system can fully explore the patientʹs motivation and attention and directly facilitate upper limb post‐stroke rehabilitation therapy. Experimental results on unimpaired participants were presented to demonstrate the feasibility of the rehabilitation system. Combining robot‐assisted training with motor imagery‐ based BCI will make future rehabilitation therapy more effective. Clinical testing is still required for further proving this assumption.