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Sample records for devonian book lungs

  1. Devonian shale

    SciTech Connect

    Not Available

    1980-01-01

    Objectives were to: estimate the in-place gas resource of Devonian Shale in the eastern United States, project possible production volumes and reserve additions of recoverable gas at various price levels with current technology, estimate the potential of new technology and its effect on production and reserve additions, examine constraints of Devonian Shale development, and compare findings with other published studies.

  2. Book lung development in the embryo, postembryo and first instar of the cobweb spider, Parasteatoda tepidariorum C. L Koch, 1841 (Araneomorphae, Theridiidae).

    PubMed

    Farley, Roger D

    2015-07-01

    Light and electron microscopy were used to compare spider book lung development with earlier studies of the development of horseshoe crab book gills and scorpion book lungs. Histological studies at the beginning of the 20th century provided evidence that spider and scorpion book lungs begin with outgrowth of a few primary lamellae (respiratory furrows, saccules) from the posterior surface of opisthosomal limb buds, reminiscent of the formation of book gills in the horseshoe crab. In spider embryos, light micrographs herein also show small primary lamellae formed at the posterior surface of opisthosomal limb buds. Later, more prominent primary lamellae extend into each book lung sinus from the inner wall of the book lung operculum formed from the limb bud. It appears most primary lamellae continue developing and become part of later book lungs, but there is variation in the rate and sequence of development. Electron micrographs show the process of air channel formation from parallel rows of precursor cells: mode I (cord hollowing), release of secretory vesicles into the extracellular space and mode II (cell hollowing), alignment and fusion of intracellular vesicles. Cell death (cavitation) is much less common but occurs in some places. Results herein support the early 20th century hypotheses that 1) book lungs are derived from book gills and 2) book lungs are an early step in the evolution of spider tracheae. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  3. A larval Devonian lungfish.

    PubMed

    Thomson, Keith S; Sutton, Mark; Thomas, Bethia

    2003-12-18

    Perhaps the most enduring of puzzles in palaeontology has been the identity of Palaeospondylus gunni Traquair, a tiny (5-60-mm) vertebrate fossil from the Middle Devonian period (approximately 385 Myr ago) of Scotland, first discovered in 1890 (refs 1-3). It is known principally from a single site (Achanarras Quarry, Caithness) where, paradoxically, it is extremely abundant, preserved in varved lacustrine deposits along with 13 other genera of fishes. Here we show that Palaeospondylus is the larval stage of a lungfish, most probably Dipterus valenciennesi Sedgwick and Murchison 1828 (ref. 5), and that development of the adult form requires a distinct metamorphosis. Palaeospondylus is the oldest known true larva of a vertebrate.

  4. Devonian of the Appalachian Basin, United States

    USGS Publications Warehouse

    Oliver, William A.; De Witt, Wallace; Dennison, John M.; Hoskins, D.M.; Huddle, John W.

    1967-01-01

    On the craton, the Middle and Upper Devonian rocks are limestones and shales, but units are thin and discontinuous except for black shale, which, over broad areas, is the latest Devonian deposit. Deposition of this shale persisted into post-Devonian times.

  5. Devonian stratigraphy of the Appalachians

    SciTech Connect

    Ferrill, B.A.; Thomas, W.A.

    1985-01-01

    Lower and lower Middle Devonian (below the top of the Onondaga and equivalent) strata in the Appalachian unmetamorphosed fold-thrust belt are relatively thin and are laterally variable in lithology, thickness, and age. South of Virginia, thickness is less than 100 m; in Virginia and farther north, thickness ranges from 100 to 450 m. Locally, rocks of this age are unconformably absent in Pennsylvania and in Virginia and farther south. Clastic rocks dominate the interval in places along the southeastern margin of the fold-thrust belt and near pinch-outs at unconformities. Elsewhere, the interval is dominated by carbonate rocks. In contrast, thick sequences of lower Devonian rocks are preserved in Appalachian metamorphic belts in New England and in Alabama. The stratigraphic distribution of upper Middle (above the top of the Onondaga and equivalent) and Upper Devonian rocks is dominated by the widespread semicircular Catskill clastic wedge, centered on southeastern Pennsylvania. Near the depocenter, the succession grades upward from deep-water black shale, through shallow-marine sandstones and mudstones, to deltaic and fluvial red beds. These facies prograde both northwestward toward the craton and southwestward along structural strike. Pelitic rocks dominate the distal part of the wedge. Distribution of the Catskill clastic wedge reflects sediment transport onto the earlier Devonian shelf from an Acadian orogenic uplift. Local basins in Maine were probably not interconnected and reflect fault-block uplifts and pull-apart basins associated with wrench faults.

  6. Desk book of the Black Lung Benefits Act: The current analysis

    SciTech Connect

    Not Available

    1992-11-01

    The current analysis is a Deskbook prepared by the staff of the Office of Administrative Law Judges, United States Department of Labor, to assist in performing legal research under the Black Lung Benefits Act. The Current Analysis combines a fundamental discussion of black lung law and processes for the new reader with recent legal trends and developments for all readers. It is periodically updated with a supplement and replacement pages.

  7. Desk book of the Black Lung Benefits Act: A current analysis. Irregular report

    SciTech Connect

    Not Available

    1992-01-01

    The current analysis is a Deskbook prepared by the staff of the Office of Administrative Law Judges, United States Department of Labor, to assist in performing legal research under the Black Lung Benefits Act. The Current Analysis combines a fundamental discussion of black lung law and processes for the new reader with recent legal trends and developments for all readers. It is periodically updated with a supplement and replacement pages.

  8. Lung cancer

    SciTech Connect

    Aisner, J.

    1985-01-01

    This book contains 13 chapters. Some of the chapter titles are: The Pathology of Lung Cancer; Radiotherapy for Non-Small-Cell Cancer of the Lung; Chemotherapy for Non-Small-Cell Lung Cancer; Immunotherapy in the Management of Lung Cancer; Preoperative Staging and Surgery for Non-Small-Cell Lung Cancer; and Prognostic Factors in Lung Cancer.

  9. Devonian conodont biochronology in geologic time calibration

    USGS Publications Warehouse

    Sandberg, C.A.; Ziegler, W.

    1996-01-01

    The conodont-based biochronology of the Devonian Period is calibrated herein on the basis of: (1) a recent, reliable radiometric dating (CLAQUE??-LONG et al. 1992) of a stratigraphic position just above the Devonian-Carboniferous boundary; and (2) new calculations of stage durations based on our estimates and those of a large number of other Devonian workers, which pertain to many stratigraphie sequences in several different paleotectonic settings globally. Using these tools we maintain the 46-m.y. duration for the Devonian Period given by the recent global timescale (GTS 89) of HARLAND et al. (1990). The main changes to GTS 89 are accomplished by raising the dating of the end of the Devonian by 9 m.y. from 363 Ma to 354 Ma and considerably shortening the bizarre estimate given by GTS 89 for the length of the oldest two Early Devonian stages. We reiterate our earlier expose?? (ZIEGLER & SANDBERG 1994) of the inaccuracies and misestimates of the ages of stage boundaries inherent in GTS 89 because of its misuse of conodont zones, which it employed as chrons to subdivide the Devonian Period. Our revisions provide the following new ages: 354 Ma, end of Devonian Period: 364 Ma. start of Famennian Stage; 369 Ma, start of Frasnian Stage; 376 Ma, start of Givetian Stage; 381 Ma, start of Eifelian Stage; 389 Ma start of Emsian Stage; 393 Ma, start of Pragian Stage; and 400 Ma, start of Lochkovian Stage and Devonian Period. Durations of stages are thus: Famennian, 10 m.y.; Frasnian, 5 m.y.; Givetian, 7 m.y.; Eifelian, 5 m.y.; Emsian, 8 m.y.; Pragian, 4 m.y.; and Lochkovian, 7 m.y.

  10. Silurian and Lower Devonian of southwestern Virginia

    SciTech Connect

    Dennison, J.M.

    1984-12-01

    Thermal maturity of the Silurian and Lower Devonian rocks in Virginia west of New River decreases southwestward. Oil and gas shows are reported. The total thickness of Lower Devonian plus Silurian strata ranges from 52 to 1000 ft (16 to 305 m), with a maximum in Buchanan County. Sandstones were derived from sources southeast of the central Appalachian basin, some from lands southeast of the outcrop belt, and some formed by reworking of sandstones within the outcrop areas. Sandstones change northwestward to shales in the Clinch and Rose Hill Formations. In the Middle Silurian and Helderberg Group, sandstones grade northwestward to limestones. Limestones in the Hancock Formation change westward to dolomite. The Onesquethaw Stage is represented by sandstone, chert, and limestone assigned to the Wildcat Valley and Huntersville Formations. In the Middle Silurian (Keefer or Big Six sandstone) and Early Devonian (Wildcat Valley Sandstone), longshore currents carried sand across the southwest end of the basin toward Kentucky. Several regional unconformities are present. These unconformities are mostly related to sea level changes, but some are probably tectonic in origin. Five unconformities are significant: 1) at base of Silurian, 2) at base of upper Helderberg over much of the area, 3) at base of Oriskany Sandstone, 4) at base of Huntersville Formation, and 5) at base of Upper Devonian black shales in extreme western Virginia, where Chattanooga Shale overlies middle Devonian to Middle Silurian strata.

  11. Cleanouts boost Devonian shale gas flow

    SciTech Connect

    Not Available

    1991-02-04

    Cleaning shale debris from the well bores is an effective way to boost flow rates from old open hole Devonian shale gas wells, research on six West Virginia wells begun in 1985 has shown. Officials involved with the study say the Appalachian basin could see 20 year recoverable gas reserves hiked by 315 bcf if the process is used on a wide scale.

  12. Technically recoverable Devonian shale gas in Kentucky

    SciTech Connect

    Kuuskraa, V.A.; Sedwick, K.B.; Thompson, K.B.; Wicks, D.E.

    1985-05-01

    This report evaluates the natural gas potential of the Devonian Age shales of Kentucky. For this, the study: (1) compiles the latest geologic and reservoir data to establish the gas in-place; (2) analyzes and models the dominant gas production mechanisms; and (3) examines alternative well stimulation and production strategies for most efficiently recovering the in-place gas. The major findings of the study include the following: (1) The technically recoverable gas from Devonian shale (Lower and Upper Huron, Rhinestreet, and Cleveland intervals) in Kentucky is estimated to range from 9 to 23 trillion cubic feet (Tcf). (2) The gas in-place for the Devonian shales in eastern Kentucky is 82 Tcf. About one half of this amount is found in the Big Sandy gas field and its immediate extensions. The remainder is located in the less naturally fractured, but organically rich area to the west of the Big Sandy. (3) The highly fractured shales in the Big Sandy area in southeast Kentucky and the more shallow shales of eastern Kentucky respond well to small-scale stimulation. New, larger-scale stimulation technology will be required for the less fractured, anisotropic Devonian shales in the rest of the state. 44 refs., 49 figs., 24 tabs.

  13. Gas composition shifts in Devonian shales

    SciTech Connect

    Schettler, P.D.; Parmely, C.R. )

    1989-08-01

    Analysis of the gas composition of Devonian shale wells indicates that the composition of produced gas shifts during the production history of the well. Possible mechanisms to explain this behavior are examined in light of field and laboratory data. Application of diffusion theory is made to explain adsorption-like behavior exhibited by some shales.

  14. The Devonian Marcellus Shale and Millboro Shale

    USGS Publications Warehouse

    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.

  15. Technically recoverable Devonian shale gas in Ohio

    SciTech Connect

    Kuushraa, V.A.; Wicks, D.E.; Sawyer, W.K.; Esposito, P.R.

    1983-07-01

    The technically recoverable gas from Devonian shale (Lower and Middle Huron) in Ohio is estimated to range from 6.2 to 22.5 Tcf, depending on the stimulation method and pattern size selected. This estimate of recovery is based on the integration of the most recent data and research on the Devonian Age gas-bearing shales of Ohio. This includes: (1) a compilation of the latest geologic and reservoir data for the gas in-place; (2) analysis of the key productive mechanisms; and, (3) examination of alternative stimulation and production strategies for most efficiently recovering this gas. Beyond a comprehensive assembly of the data and calculation of the technically recoverable gas, the key findings of this report are as follows: a substantial volume of gas is technically recoverable, although advanced (larger scale) stimulation technology will be required to reach economically attractive gas production rates in much of the state; well spacing in certain of the areas can be reduced by half from the traditional 150 to 160 acres per well without severely impairing per-well gas recovery; and, due to the relatively high degree of permeability anisotropy in the Devonian shales, a rectangular, generally 3 by 1 well pattern leads to optimum recovery. Finally, although a consistent geological interpretation and model have been constructed for the Lower and Middle Huron intervals of the Ohio Devonian shale, this interpretation is founded on limited data currently available, along with numerous technical assumptions that need further verification. 11 references, 21 figures, 32 tables.

  16. New Devonian fossil localities in Bolivia

    NASA Astrophysics Data System (ADS)

    Blieck, A.; Gagnier, P.-Y.; Bigey, F. P.; Edgecombe, G. D.; Janvier, P.; Loboziak, S.; Rachebȩuf, P. R.; Sempere, T.; Steemans, P.

    1996-11-01

    An examination of Palaeozoic sections west of Cochabamba, and west of Lake Poopó, in western Bolivia, was conducted during a field expedition in 1991. The Río Iglesiani valley, west of Cochabamba, surprisingly yielded a Middle Devonian age to all the visited sites, originally supposed to be Ordovician. This result is based on spores, shelly faunas (brachiopods and bivalves), and trilobites. The Copacabana de Andamarca section, west of Lake Poopó, is also dated as Middle Devonian on account of its rather rich fauna (bryozoans, corals, brachiopods, conulariids, hyolithids, tentaculitids, ostracodes, trilobites, crinoids, vertebrates). Both localities correlate to the Icla and/or Huamampampa Formation of the Tarabuco area and Subandean belt, and to the Belén and/or Sica Sica Formation of the northern Altiplano.

  17. Geologic analysis of Devonian Shale cores

    SciTech Connect

    1982-02-01

    Cleveland Cliffs Iron Company was awarded a DOE contract in December 1977 for field retrieval and laboratory analysis of cores from the Devonian shales of the following eleven states: Michigan, Illinois, Indiana, Ohio, New York, Pennsylvania, West Virginia, Maryland, Kentucky, Tennessee and Virginia. The purpose of this project is to explore these areas to determine the amount of natural gas being produced from the Devonian shales. The physical properties testing of the rock specimens were performed under subcontract at Michigan Technological University (MTU). The study also included LANDSAT information, geochemical research, structural sedimentary and tectonic data. Following the introduction, and background of the project this report covers the following: field retrieval procedures; laboratory procedures; geologic analysis (by state); references and appendices. (ATT)

  18. Biogeography of late Silurian and devonian rugose corals

    USGS Publications Warehouse

    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.

  19. Devonian shelf basin, Michigan basin, Alpena region

    SciTech Connect

    Gutschick, R.C.

    1986-08-01

    This biostratigraphic study involves the Devonian paleogeography-paleoecology-paleobathymetry of the transition from carbonate platform shelf margin to basinal sedimentation for the northern part of the Michigan basin in the Alpena region. Shelf-basin analysis is based on lithofacies, rock colors, concretion, biostratigraphy, paleoecology of faunas - especially microfaunas and trace fossils - stratified water column, eustasy, and application of Walther's Law. Field observations were made on Partridge Point along Lake Huron, where type sections of the Middle Devonian Thunder Bay Limestone and Late Devonian Squaw Bay Limestone are exposed; and the Antrim black shale at Paxton quarry. The Thunder Bay Limestone evolved as a carbonate platform, subtidal shelf-margin aerobic environment dominated by sessile benthic coralline organisms and shelly fauna, but not reef framework. The Squaw Bay Limestone is transitional shelf to basin, with aspects of slope environment and deeper water off-platform, pelagic organic biostromal molluscan-conodont carbonate deposited during the onset of a stratified water column (dysaerobic benthos-polychaete. agglutinated tubes, sulfides) and pycnocline. The Antrim Shale, in an exceptional black shale exposure in the Paxton quarry, represents deep-water basinal deposition whose bottom waters lacked oxygen. Faunas (conodonts, styliolines, radiolarians) and floras (tasmanitids, calamitids, palynomorphs) are from the aerobic pelagic realm, as indicated from concretions and shale fossil evidence. A benthos is lacking, except for bioturbation from organisms introduced by entrained oxygenated distal turbidite dispersion into the barren bottom black muds. Basinal hydrocarbon source rocks are abundant and updip carbonate reservoirs rim the basin. The Antrim Shale sequence contains the interval of Frasnian-Famennian faunal extinction.

  20. Analysis of eastern Devonian gas shales production data

    SciTech Connect

    Gatens, J.M.; Stanley, D.K.; Lancaster, D.E.; Lee, W.J.; Lane, H.S.; Watson, A.T.

    1989-05-01

    Production data from more than 800 Devonian shale wells have been analyzed. Permeability-thickness product and gas in place estimated from production data have been found to correlate with well performance. Empirical performance equations, production type curves, and an analytical dual-porosity model with automatic history-matching scheme were developed for the Devonian shale.

  1. 18 CFR 270.306 - Devonian shale wells in Michigan.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Devonian shale wells in... PROCEDURES Requirements for Filings With Jurisdictional Agencies § 270.306 Devonian shale wells in Michigan... shale in Michigan shall file an application that contains the following items: (a) FERC Form No. 121;...

  2. 18 CFR 270.306 - Devonian shale wells in Michigan.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Devonian shale wells in... PROCEDURES Requirements for Filings With Jurisdictional Agencies § 270.306 Devonian shale wells in Michigan... shale in Michigan shall file an application that contains the following items: (a) FERC Form No. 121;...

  3. 18 CFR 270.306 - Devonian shale wells in Michigan.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Devonian shale wells in... PROCEDURES Requirements for Filings With Jurisdictional Agencies § 270.306 Devonian shale wells in Michigan... shale in Michigan shall file an application that contains the following items: (a) FERC Form No. 121;...

  4. Devonian radiolarians and tentaculitids from central Laos

    NASA Astrophysics Data System (ADS)

    Thassanapak, Hathaithip; Udchachon, Mongkol; Burrett, Clive

    2012-10-01

    A 4 m thick section of silicified shales from Ban Phonxai in central Laos contains the radiolarians Trilonche davidi, T. hindea, T. minax, T. palimbola, Stigmosphaerostylus spp. and Ceratoikiscum ? sp. and the tentaculitids Homoctenus ultimus and Costulatostylionina vesca which together indicate a Frasnian age. This pelagic, deep shelf fauna from the Indochina Terrane is similar to that from South China and shows that tentaculitids may be common and biostratigraphically useful in radiolarian cherts and shales in South East Asia. This discovery probably necessitates mapping of the Late Devonian Phon Tiou Fm in this area which is currently mapped as the Early Carboniferous Boulapha Formation.

  5. Evolution of Devonian carbonate-shelf margin, Nevada

    USGS Publications Warehouse

    Morrow, J.R.; Sandberg, C.A.

    2008-01-01

    The north-trending, 550-km-long Nevada segment of the Devonian carbonate-shelf margin, which fringed western North America, evidences the complex interaction of paleotectonics, eustasy, biotic changes, and bolide impact-related influences. Margin reconstruction is complicated by mid-Paleozoic to Paleogene compressional tectonics and younger extensional and strike-slip faulting. Reports published during the past three decades identify 12 important events that influenced development of shelf-margin settings; in chronological order, these are: (1) Early Devonian inheritance of Silurian stable shelf inargin, (2) formation of Early to early Middle 'Devonian shelf-margin basins, (3) propradation of later Middle Devonian shelf margin, (4) late Middle Devonian Taghanic ondap and continuing long-term Frasnian transgression, (5) initiation of latest Middle Devonian to early Frasnian proto-Antler orogenic forebulge, (6) mid-Frasnian Alamo Impact, (7) accelerated development of proto-Antler forebulge and backbulge Pilot basin, (8) global late Frasnian sentichatovae sea-level rise, (9) end-Frasnian sea-level fluctuations and ensuing mass extinction, (10) long-term Famennian regression and continept-wide erosion, (11) late Famennian emergence: of Ahtler orogenic highlands, and (12) end-Devonian eustatic sea-level fall. Although of considerable value for understanding facies relationships and geometries, existing standard carbonate platform-margin models developed for passive settings else-where do not adequately describe the diverse depositional and, structural settings along the Nevada Devonian platform margin. Recent structural and geochemical studies suggest that the Early to Middle Devonian-shelf-margin basins may have been fault-bound and controlled by inherited Precambrian structure. Subsequently, the migrating latest Middle to Late Devonian Antler orogenic forebulge exerted a dominant control on shelf-margin position, morphology, and sedimentation. ??Geological Society of

  6. The Devonian trilobites of Brazil: A summary

    NASA Astrophysics Data System (ADS)

    Carvalho, Maria da Gloria Pires de; Ponciano, Luiza Corral Martins de Oliveira

    2015-12-01

    Devonian trilobites are found in three major Paleozoic intracratonic basins of Brazil (Amazonas, Parnaíba, and Paraná). The trilobites represent the families Homalonotidae, Dalmanitidae, and Calmoniidae. The distribution of these taxa in the Brazilian territory is summarized here because of their remarkable scientific and historical importance, and a revised taxonomy and lithostratigraphy of the Devonian (Pragian - Famennian) trilobites from Brazil is presented, based on new research and recent literature. Homalonotids and dalmanitids are relatively cosmopolitan, whereas calmoniids are more endemic and seem to have been restricted to marine cold-waters of the southern hemisphere (Malvinokaffric Realm). Although the trilobites within the Brazilian intracratonic basins are approximately contemporaneous, they show various patterns of endemism and biogeographical affinities with other Malvinokaffric areas such as Bolivia, South Africa, and the Falkland (Malvinas) Islands. At family level, therefore, trilobite diversity from Brazil is comparatively low, which may indicate biogeographical filtering related to the distance and/or remoteness of the Brazilian basins from more open oceanic waters.

  7. Middle Devonian liverwort herbivory and antiherbivore defence.

    PubMed

    Labandeira, Conrad C; Tremblay, Susan L; Bartowski, Kenneth E; VanAller Hernick, Linda

    2014-04-01

    To test the extent of herbivory in early terrestrial ecosystems, we examined compression-impression specimens of the late Middle Devonian liverwort Metzgeriothallus sharonae, from the Catskill Delta deposit of eastern New York state. Shale fragments of field-collected specimens were processed by applying liquid nitrocellulose on exposed surfaces. After drying, the film coatings were lifted off and mounted on microscope slides for photography. Unprocessed fragments were photographed under cedarwood oil for enhanced contrast. An extensive repertoire of arthropodan-mediated herbivory was documented, representing three functional feeding groups and nine subordinate plant-arthropod damage types (DTs). The herbivory is the earliest occurrence of external foliage-feeding and galling in the terrestrial fossil record. Our evidence indicates that thallus oil body cells, similar to the terpenoid-containing oil bodies of modern liverworts, were probably involved in the chemical defence of M. sharonae against arthropod herbivores. Based on damage patterns of terrestrial plants and an accompanying but sparse body-fossil record, Devonian arthropodan herbivores were significantly smaller compared to those of the later Palaeozoic. These data collectively suggest that a broad spectrum herbivory may have had a more important role in early terrestrial ecosystems than previously thought.

  8. Reservoir potential in Lower Devonian strata of Illinois

    SciTech Connect

    Whitaker, S.T. )

    1989-08-01

    Lower Devonian strata have considerable potential for hydrocarbon reserves in the Illinois basin; however, there has not yet been a major exploration effort for Lower Devonian reservoirs in the basin, nor has an adequate model been developed to explain distribution of these reservoirs. Due to the lack of exploration, production from these strata is presently limited to a few fields in south-central and southwestern Illinois. A review of data available at the Illinois State Geological Survey indicates that most Lower Devonian production in Illinois is from dolomitized cherty limestones in the Clear Creek Formation and Grassy Knob Chert. Minor production has also been noted in similar facies in the Bailey Limestone. Reservoir development within these strata is caused by dolomitization of slightly porous limestone beds and occurs in proximity to the beds' subcrop at the sub-Kaskaskia (pre-Middle Devonian) unconformity. The best reservoir development appears to be along paleotopographic highs on the Lower Devonian surface. Traps are most commonly formed where porous dolomitic beds, truncated at the sub-Kaskaskia unconformity are underlain by tight cherty limestones and overlain by tight Middle Devonian carbonates. Traps may also be formed downdip from porosity truncations where trends of porous Lower Devonian strata coincide with structural closures. The geometry and distribution of known reservoirs and traps in Lower Devonian carbonates indicate there may be several productive fairways in the basin. Exploration for and exploitation of these plays will depend on an increased understanding of Lower Devonian strata utilizing exploration models such as the one presented here.

  9. W. Canada's Devonian resource significant even at low gas prices

    SciTech Connect

    Waghmare, R.R.; Dallaire, S.M.; Conn, R.F. )

    1993-11-29

    This article summarizes Part 2 of Geological Survey of Canada Bulletin 452, entitled Devonian Gas Resources of the Western Canada sedimentary basin (WCSB). It provides supply curves and summary estimates of economic potential of the undiscovered natural gas resources estimated to exist in the Devonian system of the WCSB. The methodology constructed to estimate the economic potential is also described, along with major assumptions with regard to engineering inputs and economic parameters. The report concludes that, in the long-term, significant economically recoverable resources remain to be discovered in the Devonian system.

  10. Distinguished Books.

    ERIC Educational Resources Information Center

    Marles, Daisy; Ink, Gary

    1999-01-01

    Presents the following lists of distinguished books: "Best Books of 1998"; "Best Young Adult Books"; "Notable Children's Videos"; "Best Children's Books"; "Notable Recordings for Children"; "Notable Software and Web Sites for Children"; "Quick Picks for Reluctant Young Adult…

  11. Edgecliff reefs - Devonian temperate water carbonate deposition

    SciTech Connect

    Wolosz, T.H. )

    1991-03-01

    The Middle Devonian Edgecliff Member of the Onondaga Formation in New York and Ontario, Canada, is a coral-rich, reefy,' crinoidal grainstone/packstone. The reefs contain only rare stromatoporoids and are devoid of algae, having been constructed by a fauna of mound and thicket-forming branching colonial rugosans, and large sheet favositids that populated grainstone/packstone flank beds and banks. Despite the restricted fauna, the reefs display a variety of growth patterns. Rugosan mounds range in size from 2-3 m diameter by 1 m thick, up to 230 m diameter by 15 m thick. Composite structures consist of interbedded rugosan buildups and packstone/grainstone flanks, ranging from shield-shaped reefs (240 m diameter by 6 m thick) in which the rugosans occur only as thickets, to pinnacle reefs (up to 3 km diameter by 60 m thick) in which rugosan mounds are interbedded with crinoidal flanks. Geographic distribution of these reef types and analysis of surrounding facies suggests that reef growth pattern was controlled by water depth and local rate of subsidence. Despite superfacial resemblance to modern deep water ahermatypic coral mounds and thickets, abundant coral breakage and overturning, and erosion of at least one reef core during an intermediate stage of reef growth supports a shallow water origin of these reefs. It is suggested that the Edgecliff and its reefs represent an example of Devonian cool water carbonate deposition, a hypothesis supported by a trend of increasing stromatoporoid abundance westwards across New York (in the direction of the paleo-equator).

  12. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Manohar, C. S.

    2015-02-01

    The subject of the theory of vibrations has carried an aesthetic appeal to generations of engineering students for its richness of ideas, and for the intellectual challenges it offers. Also, the diverse range of its applications (covering civil, mechanical, automotive, and aerospace structures) has provided obvious motivations for its study. For most students, the subject provides, perhaps, the first encounter in substantial application of mathematical tools (differential equations, calculus of variations, Fourier/Laplace transforms, and matrix algebra) to engineering problems. The intimate relationship that the subject of mechanics has with mathematics strikes home probably for the first time. While teaching this subject, the instructor is spoilt for choice in selecting a text book and so are the students who wish to pursue a self-study of the subject. Many luminaries in the field have offered their own exposition of the subject: starting from the classics of Rayleigh, Timoshenko, Den Hartog, Bishop and Johnson, and the works of more recent vintage (e.g., the books by Meirovich, Clough, and Penzien, and works with computational flavour, such as, those by Bathe and Petyt), several works easily come to one's mind. Given this milieu, it requires a distinctive conviction to write a new book on this subject. And, here we have a book, written by a practitioner, which aims to deal with fundamental aspects of vibrations of engineering systems. The scepticism that this reviewer had on the need for having one more such book vanished as he browsed through the book and read selectively a few sections. The author's gift for elegant explanations is immediately noticeable even in such a preliminary reading. After a more careful reading, the reviewer has found this book to be insightful and he considers the book to be a welcome addition to the family of books on vibration engineering. The author has struck a fine balance between physical explanations, mathematical niceties

  13. Early forest soils and their role in Devonian global change

    SciTech Connect

    Retallack, G.J.

    1997-04-25

    A paleosol in the Middle Devonian Aztec Siltstone of Victoria Land, Antarctica, is the most ancient known soil of well-drained forest ecosystems. Clay enrichment and chemical weathering of subsurface horizons in this and other Devonian forested paleosols culminate a long-term increase initiated during the Silurian. From Silurian into Devonian time, red clayey calcareous paleosols show a greater volume of roots and a concomitant decline in the density of animal burrows. These trends parallel the decline in atmospheric carbon dioxide determined from isotopic records of pedogenic carbonate in these same paleosols. The drawdown of carbon dioxide began well before the Devonian appearance of coals, large logs, and diverse terrestrial plants and animals, and it did not correlate with temporal variation in volcanic or metamorphic activity. The early Paleozoic greenhouse may have been curbed by the evolution of rhizospheres with an increased ratio of primary to secondary production and by more effective silicate weathering during Silurian time. 14 refs., 3 figs.

  14. Early Forest Soils and Their Role in Devonian Global Change

    PubMed

    Retallack

    1997-04-25

    A paleosol in the Middle Devonian Aztec Siltstone of Victoria Land, Antarctica, is the most ancient known soil of well-drained forest ecosystems. Clay enrichment and chemical weathering of subsurface horizons in this and other Devonian forested paleosols culminate a long-term increase initiated during the Silurian. From Silurian into Devonian time, red clayey calcareous paleosols show a greater volume of roots and a concomitant decline in the density of animal burrows. These trends parallel the decline in atmospheric carbon dioxide determined from isotopic records of pedogenic carbonate in these same paleosols. The drawdown of carbon dioxide began well before the Devonian appearance of coals, large logs, and diverse terrestrial plants and animals, and it did not correlate with temporal variation in volcanic or metamorphic activity. The early Paleozoic greenhouse may have been curbed by the evolution of rhizospheres with an increased ratio of primary to secondary production and by more effective silicate weathering during Silurian time.

  15. Devonian of the Northern Rocky Mountains and plains

    USGS Publications Warehouse

    Sandberg, Charles A.; Mapel, William J.

    1967-01-01

    5. Undivided uppermost Devonian (Famennian, to V-VI) and lowermost Mississippian (Tournaisian, cuI-lower cuIIα) carbonaceous and clastic rocks deposited in six shallow basins interspersed among areas uplifted during the penecontemporaneous Antler orogeny.

  16. Devonian tides: a driver for the evolution of terrestrial vertebrates?

    NASA Astrophysics Data System (ADS)

    Byrne, Hannah; Green, Mattias

    2017-04-01

    The Devonian era saw one of the biggest evolutionary phases for Vertebrates, branching off from lobed-finned fish (sarcopterygians) to develop limbs enabling the transition from a marine to a terrestrial life. It has recently been suggested that the evolutionary pressure came from unusually large semidiurnal tides at the time, leaving individuals stranded in rock pools for up to a fortnight. It was therefore advantageous if the organism had some form of mechanism to transition between these pools, and so brought about the development of limbs. Here, we simulate the tides from the Devonian using the dedicated tidal model OTIS and a series of Devonian plate reconstructions. The reconstructions span the entire Devonian era (410 Mya - 340 Mya) and comprise of Classic and Alternative models of the Devonian. The results shows that as Gondwana and Laurasia collided, the ocean basin between them did go through several resonances, indeed producing unusually large local tides and associated spring-neap cycles. This not only support the idea that tides produced the pressure for the evolution of tetrapods, but can also have contributed to the vast areas of anoxia implied by the sediments from the period which led to mass extinction events during the late Devonian.

  17. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Clevers, Jan G. P. W.

    2016-09-01

    For many years a good introductory book for undergraduate and postgraduate students on remote sensing of the Earth's land surface, which was not starting with an emphasis on traditional photographic techniques, was missing. In 2010 the first edition of the book Fundamentals of Satellite Remote Sensing by Emilio Chuvieco and Alfredo Huete was published by CRC Press and it was filling this gap. Now the second edition by Emilio Chuvieco was published by CRC Press. This second edition is made more attractive by the use of colour and including colour illustrations instead of the black-and-white ones in the first edition.

  18. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Mishchenko, Michael I.

    2017-07-01

    This fundamental (and in many respects encyclopedic) 755-page monograph was published as part of the ;Mario Boella Series on Electromagnetism in Information and Communication; edited by P. L. E. Uslenghi. The main purpose of the book is systematic exposition of several important aspects of the electromagnetic scattering theory along with the presentation of the requisite mathematical apparatus and illustrative numerical results. What distinguishes this volume from the vast majority of related books is the extensive treatment of the time-domain scattering theory.

  19. Live birth in the Devonian period.

    PubMed

    Long, John A; Trinajstic, Kate; Young, Gavin C; Senden, Tim

    2008-05-29

    The extinct placoderm fishes were the dominant group of vertebrates throughout the Middle Palaeozoic era, yet controversy about their relationships within the gnathostomes (jawed vertebrates) is partly due to different interpretations of their reproductive biology. Here we document the oldest record of a live-bearing vertebrate in a new ptyctodontid placoderm, Materpiscis attenboroughi gen. et sp. nov., from the Late Devonian Gogo Formation of Australia (approximately 380 million years ago). The new specimen, remarkably preserved in three dimensions, contains a single, intra-uterine embryo connected by a permineralized umbilical cord. An amorphous crystalline mass near the umbilical cord possibly represents the recrystallized yolk sac. Another ptyctodont from the Gogo Formation, Austroptyctodus gardineri, also shows three small embryos inside it in the same position. Ptyctodontids have already provided the oldest definite evidence for vertebrate copulation, and the new specimens confirm that some placoderms had a remarkably advanced reproductive biology, comparable to that of some modern sharks and rays. The new discovery points to internal fertilization and viviparity in vertebrates as originating earliest within placoderms.

  20. Distinguished Books.

    ERIC Educational Resources Information Center

    Bowker Annual Library and Book Trade Almanac, 1994

    1994-01-01

    This section includes lists compiled by the American Library Association (ALA) of the best adult books of 1993, including fiction, poetry, and nonfiction; the best young adult books; the best children's books; best sellers; and recipients of literary prizes. (LRW)

  1. Children's Books. Book Reviews.

    ERIC Educational Resources Information Center

    Moulton, Kate

    1994-01-01

    Reviews 10 children's books, published or reissued 1988-93, about daily life, traditional culture, and schooling among Taos Pueblo, Zuni Pueblo, Navajo, Inuit, Guatemalan, and other Native peoples, as well as tales from Native American oral tradition, the life of a buffalo, and Cherokee and Athapascan historical fiction. Includes grade range and…

  2. Children's Books. Book Reviews.

    ERIC Educational Resources Information Center

    Moulton, Kate

    1994-01-01

    Reviews 10 children's books, published or reissued 1988-93, about daily life, traditional culture, and schooling among Taos Pueblo, Zuni Pueblo, Navajo, Inuit, Guatemalan, and other Native peoples, as well as tales from Native American oral tradition, the life of a buffalo, and Cherokee and Athapascan historical fiction. Includes grade range and…

  3. Foamed sand provides improved stimulation results from Devonian Shale

    SciTech Connect

    Strang, D.L.; Norton, J.L.

    1983-11-01

    Generally, water saturations in the Devonian Shale are low. Production records indicate minimal, if any, water in the areas producing gas or gas and oil. This low water saturation appears to be the key to stimulating the shale, especially in the oil-producing areas. The introduction of water in the stimulation fluid appears to reduce the permeability to oil, which is reflected in poorer production. The relative permeability reduction seems to be more of a problem than particle migration or clay swelling and could explain the good initial results from straight nitrogen treatments. However, the lack of a proppant, even with low closure stress, leads to very rapid declines. Water-base stimulation fluids appear to increase water saturation in the Devonian Shale. Use of 90+ quality foam with sand should provide a method of minimizing saturation changes while creating a propped fracture. Initial results indicate this technique provides better sustained production increases in the Devonian Shale. This paper defines areas of production, describes the geology and presents physical data of the Devonian Shale. It also compares results of several types of treatments that have been used in the Devonian Shale. These results indicate 90+ quality foam with sand should provide an improved stimulation technique for this formation.

  4. The Devonian Lower Carboniferous succession in Northwest Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Meor, Hakif Hassan; Lee, Chai Peng

    2005-03-01

    A new stratigraphic nomenclature is proposed for the approximately 600 m thick, mainly clastic transitional sequence between the underlying Mempelam Limestone and overlying Kubang Pasu/Singa Formation in northwest Peninsular Malaysia. This sequence represents shallow marine deposits of the continental margin of the Sibumasu Terrane during the Middle Palaeozoic (Devonian-Carboniferous). It is separated into several formations. The Timah Tasoh Formation is an approximately 76 m sequence consisting of 40 m of laminated tentaculitid shales at the base, containing Monograptus yukonensis Jackson and Lenz and Nowakia (Turkestanella) acuaria Alberti, giving an Early Devonian (Pragian-Emsian) age, and about 36 m of rhythmically interbedded, light coloured argillo-arenites. The Chepor Formation is about 90 m thick and consists mainly of thick red mudstone interbedded with sandstone beds, of Middle to Late Devonian age. A new limestone unit is recognized and named the Sanai Limestone, which contains conodonts of Famennian age. The Binjal Formation consists of red and white mudstone interbedded with sandstone beds showing Bouma sequences. The Telaga Jatoh Formation is 9 m thick and consists mainly of radiolarian chert. The Wang Kelian Formation is composed of thick red mudstone beds interbedded with silty sandstone, and contain fossils indicative of an Early Carboniferous (Visean) age. The succession was deposited on the outer shelf, with depositional environments vertically fluctuating from prodelta to basinal marine. The Devonian-Carboniferous boundary is exposed at Hutan Aji and Kampung Guar Jentik, and indicates a major regressive event during the latest Devonian.

  5. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Fonte, Cidália C.

    2016-02-01

    The use of geospatial data for a wide variety of applications has increased continuously over the last decades and a great variety of packages of open source GIS software are now available, with diverse characteristics. R was created as free software mainly for statistical computation and graphics, but offers now a large diversity of packages to process and visualize spatial data. Many books dedicated to R are available (e.g., Zuur et al., 2009; Chambers, 2008), but not many about spatial analysis in R (Bivand et al., 2008). The book under analysis is aimed for beginners both in R and in spatial analysis, and therefore can be used as a starting point for students and professionals which may want to enter the area of spatial analysis with R.

  6. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Groover, Holly

    "Most of us want to be realists about the physical world" (p. 11): Only three paragraphs into his brief book, Hebor hits a nerve. Could it be-despite our philosophical sophistication-that we continue to have a deep-seated, common sense, Einsteinian yearning to have a world out there, existing independently of us? This candid admission motivates Hebor's project, which aims to show how quantum mechanics can and should be interpreted as a realistic theory.

  7. Book It!

    ERIC Educational Resources Information Center

    Baird, Diane; Vesper, Virginia

    On the Internet, one can not only buy books but also obtain information about publishers and vendors, book reviews, authors, and other book-related information. Even electronic texts are available for downloading or browsing online. The paper discusses World Wide Web sites for many book-related information needs, whether a person is searching for…

  8. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Wegener, Daan

    Writing a biography of a complex personality and mastermind like Albert Einstein is a daunting task for any historian of science. Yet the sheer temptation of writing his biography has apparently helped to overcome scholarly scruples, as biographies of Einstein have appeared quite regularly on the market. One of them is Einstein: his Life and Universe by journalist Walter Isaacson. It is a best-seller, which is one of the reasons the book deserves a critical evaluation. Isaacson is a man of considerable repute: he has been the chairman of CNN and managing editor of Time magazine. Isaacson's Einstein is written in a style that is accessible to a wide audience. Scholars who are already familiar with Einstein's physics may still enjoy the parts of the book that deal with the relation between Einstein and the press. Indeed, the breadth of its scope is the book's major merit, as it connects the personal, scientific, public and political dimensions of Einstein's life. In this review, I discuss Isaacson's treatment of these dimensions one-by-one.

  9. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Wang, Christina Yan

    2017-02-01

    The world class Ni-Cu-PGE sulfide deposits associated with the Sudbury Igneous Complex (SIC) are quite unique on earth in the sense that the energy source and origin were triggered by a large meteorite impact event. The ore deposits in the SIC make up one of the largest Ni-Cu-PGE sulfide deposit camps in the world and have now been mined for over 100 years. This is the first complete reference book that focuses entirely on the SIC and covers the fields of economic geology, petrology, geochemistry and geophysics. The purpose of this book is to explore the linkage between sulfide and silicate magmas generated by the 1.85 Ga Sudbury impact event and to unite an understanding of the process of crustal melt sheet evolution with the formation of the magmatic sulfide mineralization. The author, Peter Lightfoot, has been based in Sudbury for 25 years. As a top scientist on magmatic Ni-Cu-PGE sulfide deposits and a Chief Geologist with the Brownfield Exploration group at Vale Base Metals, Peter has been positioned to develop and assemble the ideas presented in this book, which are perfectly balanced between industry and academia.

  10. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Martínez, Alberto A.

    The title Einstein's Generation immediately suggests names such as Ehrenfest, Ritz, Kaufmann, Born, Laue, and Laub. Staley's book discusses these individuals, but it actually has a broader scope. Both the title and the subtitle are not quite appropriate. A much more fitting title would be Michelson, Electrons, and the Rise of "Modern" Physics. The emphasis on Albert Michelson is evident in the Index: almost four columns on him, compared to just one and a half on Einstein. Likewise, "Einstein's generation" includes, for Staley, many other physicists who were quite older than Einstein, such as Lorentz, Planck, Poincaré, and Minkowski. The book exhibits a composite character because it includes and expands upon four articles that Staley had published earlier on Michelson, relativity, and the co-creation of modern and classical physics. Hence the book is partly a bridging work; it ambitiously connects areas in the history of physics, from the 1880s until 1911. Staley identifies how diverse interests produced crossfertilization, and how various disciplinary boundaries were crossed. He wants to discuss material culture, experiment, and theory, all on the same footing. Every page of the introduction seems to quadruple the scope; he writes about individuals and communities, consolidation and diversification, power and weakness, memory and neglect, the cultural and the material, the classical and the modern, and the absolute and the relative.

  11. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    van der Linden, Sebastian

    2016-05-01

    Compiling a good book on urban remote sensing is probably as hard as the research in this disciplinary field itself. Urban areas comprise various environments and show high heterogeneity in many respects, they are highly dynamic in time and space and at the same time of greatest influence on connected and even tele-connected regions due to their great economic importance. Urban remote sensing is therefore of great importance, yet as manifold as its study area: mapping urban areas (or sub-categories thereof) plays an important (and challenging) role in land use and land cover (change) monitoring; the analysis of urban green and forests is by itself a specialization of ecological remote sensing; urban climatology asks for spatially and temporally highly resolved remote sensing products; the detection of artificial objects is not only a common and important remote sensing application but also a typical benchmark for image analysis techniques, etc. Urban analyses are performed with all available spaceborne sensor types and at the same time they are one of the most relevant fields for airborne remote sensing. Several books on urban remote sensing have been published during the past 10 years, each taking a different perspective. The book Global Urban Monitoring and Assessment through Earth Observation is motivated by the objectives of the Global Urban Observation and Information Task (SB-04) in the GEOSS (Global Earth Observation System of Systems) 2012-2015 workplan (compare Chapter 2) and wants to highlight the global aspects of state-of-the-art urban remote sensing.

  12. More potential Devonian economics outlined for Western Canada basin

    SciTech Connect

    Waghmare, R.R.; Roux, L.; Brackman, C.

    1995-06-12

    This article presents further details on the analysis of economic potential in the Devonian system of the Western Canada sedimentary basin. The previous study, published as Bulletin 452 by the Geological Survey of Canada, a sector of Natural Resources Canada, presented an analysis of the economic potential in the five cost regions of the Devonian system. This article gives estimates for all 25 mature plays comprising the cost regions of the Devonian system. Estimates of economic potential by play are analyzed for both the full-cycle and half-cycle cases at two representative plant gate prices of natural gas: $44.13/thousand cu m ($1.25/Mcf) and $88.25/thousand cu m ($2.50/Mcf). Before summarizing the previous study and describing the analytical extensions. The paper defines the terminology.

  13. Study finds Devonian gas resources of western Canada attractive target

    SciTech Connect

    Reinson, G.E.; Lee, P.J. )

    1993-09-13

    This report summarizes results of a recently completed study on the conventional natural gas resources estimated to be contained in Devonian strata of the Western Canada sedimentary basin. This study is the first in a series dealing with conventional gas resources of the basin south of 62[degree] N. Lat. Estimates of regional resource potential have been prepared periodically by the Geological Survey of Canada, using systematic geological basin analysis and statistical resource evaluation methods. The major play groups in the western Canada gas project are Devonian, Permo-Carboniferous, Triassic, Deformed Belt, Lower Cretaceous Mannville group, Middle Cretaceous Colorado group, and Upper Cretaceous-Tertiary. The Devonian assessment was undertaken first because of the existing comprehensive geological data base and because there is an upside potential for finding significant reserves in relatively large economic pools. The paper describes the assessment procedures andanalyzes mature plays and conceptual plays of gas.

  14. Oldest coelacanth, from the Early Devonian of Australia.

    PubMed

    Johanson, Zerina; Long, John A; Talent, John A; Janvier, Philippe; Warren, James W

    2006-09-22

    Coelacanths are well-known sarcopterygian (lobe-finned) fishes, which together with lungfishes are the closest extant relatives of land vertebrates (tetrapods). Coelacanths have both living representatives and a rich fossil record, but lack fossils older than the late Middle Devonian (385-390 Myr ago), conflicting with current phylogenies implying coelacanths diverged from other sarcopterygians in the earliest Devonian (410-415 Myr ago). Here, we report the discovery of a new coelacanth from the Early Devonian of Australia (407-409 Myr ago), which fills in the approximately 20 Myr 'ghost range' between previous coelacanth records and the predicted origin of the group. This taxon is based on a single lower jaw bone, the dentary, which is deep and short in form and possesses a dentary sensory pore, otherwise seen in Carboniferous and younger taxa.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    da Costa, Newton C. A.; Krause, Décio

    This book contains a representative selection of Erhard Scheibe's writings on the philosophy of physics. It encompasses eight sections, with 38 papers, distributed as follows: (I) Between Rationalism and Empiricism (five papers from 1969 to 1994); (II) The Philosophy of the Physicists (five papers from 1988 to 1995); (III) Reconstruction (four papers, from 1979 to 1988); (IV) Laws of Nature (five papers, from 1989 to 1998); (V) Reduction (five papers from 1973 to 1995); (VI) Foundations of Quantum Mechanics (six papers from 1985 to 1993); (VII) Spacetime, Invariance, Covariance (four papers from 1982 to 1994), and (VIII) Mathematics and Physics (four papers from 1977 to 1997).

  17. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Mishchenko, Michael I.

    2017-01-01

    The second - revised and enlarged - edition of this popular monograph is co-authored by Michael Kahnert and is published as Volume 145 of the Springer Series in Optical Sciences. As in the first edition, the main emphasis is on the mathematics of electromagnetic scattering and on numerically exact computer solutions of the frequency-domain macroscopic Maxwell equations for particles with complex shapes. The book is largely centered on Green-function solution of relevant boundary value problems and the T-matrix methodology, although other techniques (the method of lines, integral equation methods, and Lippmann-Schwinger equations) are also covered. The first four chapters serve as a thorough overview of key theoretical aspects of electromagnetic scattering intelligible to readers with undergraduate training in mathematics. A separate chapter provides an instructive analysis of the Rayleigh hypothesis which is still viewed by many as a highly controversial aspect of electromagnetic scattering by nonspherical objects. Another dedicated chapter introduces basic quantities serving as optical observables in practical applications. A welcome extension of the first edition is the new chapter on group theoretical aspects of electromagnetic scattering by particles with discrete symmetries. An essential part of the book is the penultimate chapter describing in detail popular public-domain computer programs mieschka and Tsym which can be applied to a wide range of particle shapes. The final chapter provides a general overview of available literature on electromagnetic scattering by particles and gives useful reading advice.

  18. Eastern Devonian shales: Organic geochemical studies, past and present

    USGS Publications Warehouse

    Breger, I.A.; Hatcher, P.G.; Romankiw, L.A.; Miknis, F.P.

    1983-01-01

    The Eastern Devonian shales are represented by a sequence of sediments extending from New York state, south to the northern regions of Georgia and Alabama, and west into Ohio and to the Michigan and Ilinois Basins. Correlatives are known in Texas. The shale is regionally known by a number of names: Chattanooga, Dunkirk, Rhinestreet, Huron, Antrim, Ohio, Woodford, etc. These shales, other than those in Texas, have elicited much interest because they have been a source of unassociated natural gas. It is of particular interest, however, that most of these shales have no associated crude oil, in spite of the fact that they have some of the characteristics normally attributed to source beds. This paper addresses some of the organic geochemical aspects of the kerogen in these shales, in relation to their oil generating potential. Past organic geochemical studies on Eastern Devonian shales will be reviewed. Recent solid state 13C NMR studies on the nature of the organic matter in Eastern Devonian shales show that Eastern Devonian shales contain a larger fraction of aromatic carbon in their chemical composition. Thus, despite their high organic matter contents, their potential as a petroleum source rock is low, because the kerogen in these shales is of a "coaly" nature and hence more prone to producing natural gas.

  19. Hydrocarbon potential of Upper Devonian black shale, eastern Kentucky

    SciTech Connect

    Johnston, I.M.; Frankie, W.T.; Moody, J.R.; Kemper, J.R.; Elkin, R.R.

    1987-09-01

    The gas-producing Upper Devonian black shales of eastern Kentucky represent cycles of organic units alternating with less-organic units that were dominated by an influx of clastics from a northeastern source. This pattern of sedimentation is typical throughout the southern Appalachian basin in areas basinal to, yet still influenced by, the Catskill delta to the northwest. These black shales, which thin westward onto the Cincinnati arch, dip eastward into the Appalachian basin. To evaluate the future gas potential of Devonian shale, a data base has been compiled, consisting of specific geologic and engineering information from 5920 Devonian shale wells in Letcher, Knott, Floyd, Martin, and Pike Counties, Kentucky. The first successful gas completion in eastern Kentucky was drilled in Martin County in 1901. Comparison of initial open-flow potential (IP) and long-term production data for these wells demonstrates that higher IP values generally indicate wells of higher production potential. Areas of higher IP are aligned linearly, and these lineaments are interpreted to be related to fracture systems within the Devonian shale. These fractures may be basement influenced. Temperature log analyses indicate that the greatest number of natural gas shows occur in the lower Huron Member of the Ohio Shale. Using both the temperature log to indicate gas shows and the gamma-ray log to determine the producing unit is a workable method for selecting the interval for treatment.

  20. Air-breathing adaptation in a marine Devonian lungfish

    PubMed Central

    Clement, Alice M.; Long, John A.

    2010-01-01

    Recent discoveries of tetrapod trackways in 395 Myr old tidal zone deposits of Poland (Niedźwiedzki et al. 2010 Nature 463, 43–48 (doi:10.1038/nature.08623)) indicate that vertebrates had already ventured out of the water and might already have developed some air-breathing capacity by the Middle Devonian. Air-breathing in lungfishes is not considered to be a shared specialization with tetrapods, but evolved independently. Air-breathing in lungfishes has been postulated as starting in Middle Devonian times (ca 385 Ma) in freshwater habitats, based on a set of skeletal characters involved in air-breathing in extant lungfishes. New discoveries described herein of the lungfish Rhinodipterus from marine limestones of Australia identifies the node in dipnoan phylogeny where air-breathing begins, and confirms that lungfishes living in marine habitats had also developed specializations to breathe air by the start of the Late Devonian (ca 375 Ma). While invasion of freshwater habitats from the marine realm was previously suggested to be the prime cause of aerial respiration developing in lungfishes, we believe that global decline in oxygen levels during the Middle Devonian combined with higher metabolic costs is a more likely driver of air-breathing ability, which developed in both marine and freshwater lungfishes and tetrapodomorph fishes such as Gogonasus. PMID:20147310

  1. Eastern Madre de Dios Devonian generated large volumes of oil

    SciTech Connect

    Peters, K.E.; Wagner, J.B.; Carpenter, D.G.; Conrad, K.T.

    1997-02-24

    This is the second part of an article giving details of a Mobil Corp. regional geological, geophysical, and geochemical study of the Madre de Dios basin. The assessment covered the distribution, richness, depositional environment, and thermal maturity of Devonian source rocks.

  2. 18 CFR 270.306 - Devonian shale wells in Michigan.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) All well completion reports; (c) A gamma ray log from the closest available well bore (producing or... superimposed indications of: (1) The shale base line and the gamma ray index of 0.7 over the Devonian age... location plat showing the well for which the determination is sought and the well for which a gamma ray log...

  3. 18 CFR 270.306 - Devonian shale wells in Michigan.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) All well completion reports; (c) A gamma ray log from the closest available well bore (producing or... superimposed indications of: (1) The shale base line and the gamma ray index of 0.7 over the Devonian age... location plat showing the well for which the determination is sought and the well for which a gamma ray log...

  4. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Roberts, John T.

    Mauro Dorato's new book is subtitled "An Introduction to the History and Philosophy of Laws of Nature". This is a bit misleading: a reader previously unacquainted with any of the literature on the topic of laws of nature and related problems in the philosophy of science will find much of the book prohibitively challenging. But the book does aim for the kind of breadth and generality that one would expect from an introduction to the subject, and it serves well as a compact overview of the issues, views, arguments, and counter-arguments that have shaped the contemporary philosophical debate on laws of nature. Almost no important facet of the debate goes untouched. There are chapters or sections on: recent scholarship on the history of the notion of a law and its role in the study of nature; the characteristics of the things called "laws" in a wide range of sciences; the relations among laws, algorithmic compressibility of information, and the theory of measurement; the puzzling question of why so many laws of nature should be mathematical in form; regularity theories of laws; the universals approach to laws; the necessitarian approach to laws; skeptical eliminativism about laws; non-reductive realism about laws; the question of the supervenience of laws on non-nomic facts; the relations of laws to counterfactuals, causality, dispositions, explanation, chance, symmetry, and necessity; ceteris paribus clauses; the evolutionary contingency thesis and the question of biological laws; Wilhelm Dilthey and the alleged distinction between "nomothetic" sciences and "historical" ones; the question of psychophysical laws and the relation between this question and the problems of mental causation and free will; even the connection between the issue of psychophysical laws and Gibson's ecological theory of perception. This is an impressive range of topics, especially considering that they are all treated in only 174 pages. One result is that not all of them are treated with as

  5. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Xiao, Wenjiao

    2016-06-01

    This monograph book represents an important volume summarizing the present geological knowledge and understanding of the geodynamic evolution of large parts of the Central Asian Orogenic Belt (CAOB) or Altaids, which is one of the largest orogenic collages on Earth. The CAOB, like other major accretionary orogens, is a complex assembly of ancient microcontinents, arc terranes, accretionary wedges, fragments of oceanic volcanic islands (sea-mounts), oceanic plateaus, ophiolites, and shelf sediments from passive continental margins. The CAOB has caused much international attention due to its complicated architecture and considerably continental growth. However, after many years of investigations, some fundamental problems still remain controversial, such as the rate and volume of crustal growth, the origin of continental fragments, the detailed mechanism of accretion and collision, the role of terrane rotations during the orogeny, and the age and composition of the lower crust in Central Asia.

  6. A complete insect from the Late Devonian period.

    PubMed

    Garrouste, Romain; Clément, Gaël; Nel, Patricia; Engel, Michael S; Grandcolas, Philippe; D'Haese, Cyrille; Lagebro, Linda; Denayer, Julien; Gueriau, Pierre; Lafaite, Patrick; Olive, Sébastien; Prestianni, Cyrille; Nel, André

    2012-08-02

    After terrestrialization, the diversification of arthropods and vertebrates is thought to have occurred in two distinct phases, the first between the Silurian and the Frasnian stages (Late Devonian period) (425-385 million years (Myr) ago), and the second characterized by the emergence of numerous new major taxa, during the Late Carboniferous period (after 345 Myr ago). These two diversification periods bracket the depauperate vertebrate Romer's gap (360-345 Myr ago) and arthropod gap (385-325 Myr ago), which could be due to preservational artefact. Although a recent molecular dating has given an age of 390 Myr for the Holometabola, the record of hexapods during the Early-Middle Devonian (411.5-391 Myr ago, Pragian to Givetian stages) is exceptionally sparse and based on fragmentary remains, which hinders the timing of this diversification. Indeed, although Devonian Archaeognatha are problematic, the Pragian of Scotland has given some Collembola and the incomplete insect Rhyniognatha, with its diagnostic dicondylic, metapterygotan mandibles. The oldest, definitively winged insects are from the Serpukhovian stage (latest Early Carboniferous period). Here we report the first complete Late Devonian insect, which was probably a terrestrial species. Its 'orthopteroid' mandibles are of an omnivorous type, clearly not modified for a solely carnivorous diet. This discovery narrows the 45-Myr gap in the fossil record of Hexapoda, and demonstrates further a first Devonian phase of diversification for the Hexapoda, as in vertebrates, and suggests that the Pterygota diversified before and during Romer's gap.

  7. Porosity and permeability of eastern Devonian gas shale

    SciTech Connect

    Soeder, D.J.

    1986-01-01

    High-precision core analysis has been performed on eight samples of Devonian gas shale from the Appalachian Basin. Seven of the core samples consist of the Upper Devonian age Huron Member of the Ohio Shale, six of which came from wells in the Ohio River valley, and the seventh from a well in east-central Kentucky. The eighth core sample consists of Middle Devonian age Marcellus Shale obtained from a well in Morgantown, West Virginia. The core analysis was originally intended to supply accurate input data for Devonian shale numerical reservoir simulation. Unexpectedly, the results have also shown that there are a number of previously unknown factors which influence or control gas production from organic-rich shales of the Appalachian Basin. The presence of petroleum as a mobile liquid phase in the pores of all seven Huron Shale samples effectively limits the gas porosity of this formation to less than 0.2%, and permeability of the rock matrix to gas is less than 0.1 microdarcy at reservoir stress. The Marcellus Shale core, on the other hand, was free of a mobile liquid phase and had a measured gas porosity of approximately 10% under stress with a fairly strong ''adsorption'' component. Permeability to gas (K/sub infinity/ was highly stress-dependent, ranging from about 20 microdarcies at a net stress of 3000 psi down to about 5 microdarcies at a net stress of 6000 psi. The conclusion reached from this study is that Devonian shale in the Appalachian Basin is a considerably more complex natural gas resource than previously thought. Production potential varies widely with geographic location and stratigraphy, just as it does with other gas and oil resources. 15 refs., 8 figs., 3 tabs.

  8. Distinguished Books.

    ERIC Educational Resources Information Center

    Maryles, Daisy; Ink, Gary

    1998-01-01

    Lists best books by the American Library Association for the general reader, best young adult books, notable children's films and videos, best children's books, notable recordings for children, notable children's software and Web sites, quick picks for reluctant young adult readers, bestsellers of 1997, and literary prizes, 1997. (PEN)

  9. Book Review: Book review

    NASA Astrophysics Data System (ADS)

    Freire, Olival

    2014-05-01

    This book concerns the many lives of Hugh Everett's seminal work on the interpretation of quantum mechanics. As these many lives were spread over time, like layers, the reading of this book is like an archeological tour as well as an adventure in physics, its philosophy and history. In short, the story traces the lives of his work. The first life was around 1956-1957 when Everett, a doctoral student under John Archibald Wheeler, wrote his dissertation at Princeton University and published it in the journal Review of Modern Physics. He presented an interpretation which dispensed with the need to collapse quantum states during measurements, thus dissolving the quantum measurement problem, and consistently reproduced results from quantum mechanics using Schrödinger's equation alone. Despite the face value of such a proposal it drew little attention until the end of the 1960s. This was when the second life of Everett's work began. In 1967 Bryce DeWitt appealed to Everett's work while working on the quantization of general relativity creating what is now called the Wheeler-DeWitt equation. Furthermore, DeWitt wanted give to Everett's work a wider audience than experts in quantum gravity. Supported by the editors of Physics Today a paper by himself presenting this interpretation as one of the possible ones for quantum mechanics triggered a heated debate on the subject in the periodical. Together with this new life a layer beneath the original publication of the dissertation appeared. In contact with Everett, DeWitt discovered that the 1957 dissertation and paper had been an abridged version of a more consistently developed interpretation. The full version of the work was then published in 1973 with the enticing title, suggested by DeWitt, of "The Many-Worlds Interpretation of Quantum Mechanics." This second life was larger than the first one, indeed it is alive until today, sparking a huge amount of technical work by physicists and philosophers attempting to solve what

  10. Tetrapod trackways from the early Middle Devonian period of Poland.

    PubMed

    Niedźwiedzki, Grzegorz; Szrek, Piotr; Narkiewicz, Katarzyna; Narkiewicz, Marek; Ahlberg, Per E

    2010-01-07

    The fossil record of the earliest tetrapods (vertebrates with limbs rather than paired fins) consists of body fossils and trackways. The earliest body fossils of tetrapods date to the Late Devonian period (late Frasnian stage) and are preceded by transitional elpistostegids such as Panderichthys and Tiktaalik that still have paired fins. Claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers. Here we present well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian (Eifelian stage) age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids. They force a radical reassessment of the timing, ecology and environmental setting of the fish-tetrapod transition, as well as the completeness of the body fossil record.

  11. Devonian shale-specific computation methodology. Topical report, June 1988

    SciTech Connect

    Guidry, F.K.; Truman, R.B.; Campbell, R.L.; Harrison, C.W.

    1988-06-01

    This report presents the application of the 'Devonian Shale-specific Formation Evaluation Model' for the evaluation of geophysical well logs in the Devonian shale. A procedure is outlined for determining lithology, porosity, and bulk volume free-hydrocarbon. The logging suite commonly utilized by ResTech for evaluation of the shales is presented. However, methods were developed for obtaining reliable results in certain areas with a reduced logging suite. The final report from an analysis includes a written document containing recommended completion intervals and perforations. Also included within the report are the results presented in both a log and listed format. The log format has an 11-inch and 22-inch presentation. In addition to lithology, porosity, and bulk-volume free-hydrocarbon that are presented on the 11-inch presentation, results from the borehole television, temperature survey, and mudlog are displayed on the 22-inch wide presentation.

  12. Evaluation of Devonian-shale potential in Ohio

    SciTech Connect

    Komar, C. A.

    1981-01-01

    The purpose of this report is to inform interested oil and gas operators about EGSP results as they pertain to the Devonian gas shales of the Appalachian basin in eastern Ohio. Geologic data and interpretations are summarized, and areas where the accumulation of gas may be large enough to justify commercial production are outlined. Because the data presented in this report are generalized and not suitable for evaluation of specific sites for exploration, the reader should consult the various reports cited for more detail and discussion of the data, concepts, and interpretations presented. A complete list of EGSP sponsored work pertinent to the Devonian shales in Ohio is contained as an appendix to this report. Radioactive shale zones are also mapped.

  13. Silurian and Devonian in Vietnam—Stratigraphy and facies

    NASA Astrophysics Data System (ADS)

    Thanh, Tống Duy; Phương, Tạ Hoàng; Janvier, Philippe; Hùng, Nguyễn Hữu; Cúc, Nguyễn Thị Thu; Dương, Nguyễn Thùy

    2013-09-01

    Silurian and Devonian deposits in Viet Nam are present in several zones and regions, including Quang Ninh, East Bac Bo, and West Bac Bo Zones of the Bac Bo Region, the Dien Bien-Nghe An and Binh Tri Thien Zones of the Viet-Lao Region, and the South Trung Bo, and Western Nam Bo Zones of the South Viet Nam Region (Fig. 1). The main lithological features and faunal composition of the Silurian and Devonian Units in all these zones are briefly described. The Silurian consists of deep-water deposits of the upper parts of the Co To and Tan Mai Formations in the Quang Ninh Zone, the upper parts of the Phu Ngu Formation in the East Bac Bo Zone and the upper parts of the Long Dai and Song Ca Formations in the Viet-Lao Region. Shallow water facies Silurian units containing benthic faunas are more widely distributed, including the upper part of the Sinh Vinh and Bo Hieng Formations in the West Bac Bo Zone, the Kien An Formation in the Quang Ninh Zone, and, in the Viet-Lao Region, the Dai Giang Formation and the upper part of the Tay Trang Formation. No Lower and Middle Devonian deposits indicate deep water facies, but they are characterized by different shallow water facies. Continental to near shore, deltaic facies characterize the Lower Devonian Song Cau Group in the East Bac Bo Zone, the Van Canh Formation in the Quang Ninh Zone, and the A Choc Formation in the Binh Tri Thien Zone. Similar facies also occur in the Givetian Do Son Formation of the Quang Ninh Zone, and the Tan Lap Formation in the East Bac Bo Zone, and consist of coarse terrigenous deposits—cross-bedded conglomerates, sandstone, etc. Most Devonian units are characterized by shallow marine shelf facies. Carbonate and terrigenous-carbonate facies dominate, and terrigenous facies occur in the Lower and Middle Devonian sections in some areas only. The deep-water-like facies is characteriztic for some Upper Devonian formations in the Bac Bo (Bang Ca and Toc Tat Formations) and Viet-Lao Regions (Thien Nhan and

  14. Devonian brachiopods of southwesternmost laurentia: Biogeographic affinities and tectonic significance

    USGS Publications Warehouse

    Boucot, A.J.; Poole, F.G.; Amaya-Martinez, R.; Harris, A.G.; Sandberg, C.A.; Page, W.R.

    2008-01-01

    Three brachiopod faunas discussed herein record different depositional and tectonic settings along the southwestern margin of Laurentia (North America) during Devonian time. Depositional settings include inner continental shelf (Cerros de Los Murcielagos), medial continental shelf (Rancho Placeritos), and offshelf continental rise (Rancho Los Chinos). Ages of Devonian brachiopod faunas include middle Early (Pragian) at Rancho Placeritos in west-central Sonora, late Middle (Givetian) at Cerros de Los Murcielagos in northwestern Sonora, and late Late (Famennian) at Rancho Los Chinos in central Sonora. The brachiopods of these three faunas, as well as the gastropod Orecopia, are easily recognized in outcrop and thus are useful for local and regional correlations. Pragian brachiopods dominated by Acrospirifer and Meristella in the "San Miguel Formation" at Rancho Placeritos represent the widespread Appohimchi Subprovince of eastern and southern Laurentia. Conodonts of the early to middle Pragian sulcatus to kindlei Zones associated with the brachiopods confirm the ages indicated by the brachiopod fauna and provide additional information on the depositional setting of the Devonian strata. Biostratigraphic distribution of the Appohimchi brachiopod fauna indicates continuous Early Devonian shelf deposition along the entire southern margin of Laurentia. The largely emergent southwest-trending Transcontinental arch apparently formed a barrier preventing migration and mixing of many genera and species of brachiopods from the southern shelf of Laurentia in northern Mexico to the western shelf (Cordilleran mio-geocline) in the western United States. Middle Devonian Stringocephalus brachiopods and Late Devonian Orecopia gastropods in the "Los Murcielagos Formation" in northwest Sonora represent the southwest-ernmost occurrence of these genera in North America and date the host rocks as Givetian and Frasnian, respectively. Rhynchonelloid brachiopods (Dzieduszyckia sonora) and

  15. Lichen metabolism identified in Early Devonian terrestrial organisms

    NASA Astrophysics Data System (ADS)

    Jahren, A. Hope; Porter, Steven; Kuglitsch, Jeffrey J.

    2003-02-01

    We used δ13C values to identify lichen metabolism in the globally distributed Early Devonian (409 386 Ma) macrofossil Spongiophyton minutissimum, which had been alternatively interpreted as a green plant of bryophyte grade or as a lichen, based on its morphology. Extant mosses and hornworts exhibited a range of δ13Ctissue values that was discrete from that of extant lichens. The δ13Ctissue values of 96 S. minutissimum specimens coincided with δ13Ctissue values of extant lichens. In contrast, S. minutissimum δ13Ctissue values showed no similarity to bryophyte carbon isotope values. The identification of large global populations of lichens during the Early Devonian may indicate that lichen-accelerated soil formation fostered the development of Paleozoic terrestrial ecosystems.

  16. Sour-gas potential in Devonian of western Alberta, Canada

    SciTech Connect

    Podruski, J.A.

    1989-03-01

    The Geological Survey of Canada is presently conducting an assessment of the undiscovered gas resources of the Western Canada sedimentary basin using the exploration play analysis technique. The first system being examined is the Devonian, which as been divided into four exploration districts based on differences in depositional and tectonic histories, hydrocarbon compositions, and exploration practices. The western Alberta sour gas district contains most of the Devonian gas reserves (10 trillion ft/sup 3/ of marketable gas) and potential in 12 exploration plays. Production in the Upper Devonian Swan Hills, Leduc, and Nisku formations is from the updip (northeast), basinward termination of carbonate shelves or large reef complexes and their associated patch and pinnacle reefs. Mapping the reef or shelf carbonate transition to basinal shale and carbonate delineates the play areas in these formations. Production in the Upper Devonian Wabamun Formation is from stratigraphic traps at shelf carbonate/shelf evaporite transitions and in structural-stratigraphic traps in dolomitized shelf carbonate. Pools in these plays typically contain from 50 to 500 billion ft/sup 3/ of marketable gas, have 10-30% H/sub 2/S, and occur at depths from 8000 to 15,000 ft. Potential in most plays is large, considering that between 90 and 99% of the play areas are unexplored. Present exploration is still concentrating on the conventional shelf margin or reef traps, such as in the area of the recent Caroline discovery. Subtle intrashelf traps are only beginning to be explored and could constitute a major resource target of the future, provided that economic conditions and improvements in seismic technology and geologic understanding will sustain the exploration effort in this district.

  17. Geology of the Devonian black shales of the Appalachian basin

    USGS Publications Warehouse

    Roen, J.B.

    1983-01-01

    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. Concurrent with periodic and varied economic exploitations of the black shales are geologic studies. 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 produced a regional stratigraphic network that correlates the 15-foot sequence in Tennessee with 3,000 feet of interbedded black and gray shales in central New York. The classic Devonian black-shale sequence in New York has been correlated 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 and provided a basis for correlations with the black shales of the Illinois and Michigan basins. Areal distribution of selected shale units along with paleocurrent studies, clay mineralogy, and geochemistry suggests variations in the sediment source and transport directions. Current structures, faunal evidence, lithologic variations, and geochemical studies provide evidence to support interpretation of depositional environments. In addition, organic geochemical data combined with stratigraphic and structural characteristics of the shale within the basin allow an evaluation of the resource potential of natural gas in the Devonian shale sequence.

  18. Technically recoverable Devonian shale gas in West Virginia

    SciTech Connect

    Kuuskraa, V.A.; Wicks, D.E.

    1984-12-01

    This report evaluates the natural gas potential of the Devonian Age shales of West Virginia. For this, the study: (1) compiles the latest geological and reservoir data to establish the gas in-place; (2) analyzes and models the dominant gas production mechanisms; and (3) examines alternative well stimulation and production strategies for most efficiently recovering the in-place gas. The major findings of the study include the following: (1) The technically recoverable gas from Devonian shale (Huron, Rhinestreet, and Marcellus intervals) in West Virginia is estimated to range from 11 to 44 trillion cubic feet. (2) The Devonian shales in this state entail great geological diversity; the highly fractured, permeable shales in the southwest respond well to traditional development practices while the deep, tight shales in the eastern and northern parts of the state will require new, larger scale well stimulation technology. (3) Beyond the currently developed Huron and Rhinestreet shale intervals, the Marcellus shale offers a third attractive gas zone, particularly in the north central portion of the state. 21 references, 53 figures, 27 tables.

  19. Magnetostratigraphy, Late devonian iridium anomaly, and impact hypotheses

    SciTech Connect

    Hurley, N.F.; Van der Voo, R. )

    1990-04-01

    Paleomagnetism, sedimentology, and fine-scale stratigraphy have been integrated to explain the origin of an iridium anomaly in the Late Devonian of Western Australia. Thermal demagnetization experiments were carried out on 93 specimens of marginal-slope limestone form the northern Canning Basin. Samples are from a condensed sequence of deep-water (> 100 m) Frutexites microstromatolites. Frutexites is a shrublike cyanobacterial organism that probably precipitated hematite, or a metastable precursor, from sea water. When plotted within the microstratigraphic framework for the study area, the observed characteristic directions from the sampled interval (14.5 cm thick) are in five discrete, layer-parallel, normal- and reversed-polarity zones. The measured northeast-southwest declinations and shallow inclinations probably record Late Devonian magnetostratigraphy on a centimetre scale. The Frutexites bed studied there occurs close to the Frasnian/Famennian (Late Devonian) boundary, a time of mass extinction of a wide variety of marine organisms throughout the world. Anomalously high iridium concentrations observed in the Frutexites bed have suggested to some authors that the mass extinction was caused by meteorite impact. This study concludes that iridium, which is present over the span of five layer-parallel magnetic reversals, was concentrated over a long period of time by biologic processes. Thus, the Canning Basin iridium anomaly may be unrelated to meteorite impact.

  20. A lamprey from the Devonian period of South Africa.

    PubMed

    Gess, Robert W; Coates, Michael I; Rubidge, Bruce S

    2006-10-26

    Lampreys are the most scientifically accessible of the remaining jawless vertebrates, but their evolutionary history is obscure. In contrast to the rich fossil record of armoured jawless fishes, all of which date from the Devonian period and earlier, only two Palaeozoic lampreys have been recorded, both from the Carboniferous period. In addition to these, the recent report of an exquisitely preserved Lower Cretaceous example demonstrates that anatomically modern lampreys were present by the late Mesozoic era. Here we report a marine/estuarine fossil lamprey from the Famennian (Late Devonian) of South Africa, the identity of which is established easily because many of the key specializations of modern forms are already in place. These specializations include the first evidence of a large oral disc, the first direct evidence of circumoral teeth and a well preserved branchial basket. This small agnathan, Priscomyzon riniensis gen. et sp. nov., is not only more conventionally lamprey-like than other Palaeozoic examples, but is also some 35 million years older. This finding is evidence that agnathans close to modern lampreys had evolved before the end of the Devonian period. In this light, lampreys as a whole appear all the more remarkable: ancient specialists that have persisted as such and survived a subsequent 360 million years.

  1. Subsurface sequence stratigraphy of Devonian carbonates, Canning basin, Western Australia

    SciTech Connect

    Southgate, P.N.; Jackson, J.; Kennard, J.M.; O'Brien, P.E.; Passmore, V.L.; Lindsay, J.F. ); Holmes, A.E.; Christie-Blick, N. )

    1991-03-01

    The Canning basin of Western Australia is best known for its Devonian reef complexes. in 1990 the Australian Bureau of Mineral Resources (BMR) began a sequence stratigraphic study of key parts of the basin. This work integrates industry seismic and well data with two deep-crustal, regional seismic lines acquired by BMR in 1988. Initial work on the Lennard Shelf and adjacent Fitzroy trough has established a new sequence stratigraphy. At the margin of the Fitzroy trough, the most prominent features on seismic sections are alternating wedge-shaped and tabular bodies up to 150 m and 50 m thick, respectively. Internal reflections in the wedge-shaped bodies show downlap toward the basin and onlap toward the platform margin. On strike lines these wedges exhibit complex lensoidal geometries. Drillcore indicates that the wedges comprise basement-derived conglomerates with a sandy calcareous matrix. Seismic and well data suggest five Late Devonian sequences. The wedges and oblique prograding units are thickest and most easily recognized in the upper three sequences (Late Frasnian-Famennian ). The underlying thinner sequences probably correlate with the classic back-stepping Frasnian reefs identified in outcrop by Playford. Recognition of lowstand deposits in the Devonian reef complexes represent a new hydrocarbon exploration play.

  2. Climate effects caused by land plant invasion in the Devonian

    NASA Astrophysics Data System (ADS)

    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.

  3. The oldest articulated chondrichthyan from the Early Devonian period.

    PubMed

    Miller, Randall F; Cloutier, Richard; Turner, Susan

    2003-10-02

    Chondrichthyans (including living sharks, skates, rays and chimaeras) have a fossil record of scales and dermal denticles perhaps dating back to the Late Ordovician period, about 455 million years ago. Their fossil tooth record extends to the earliest Devonian period, almost 418 million years ago, whereas the oldest known articulated shark remains date from the Early Devonian period, about 394 million years ago. Here we report the discovery of an articulated shark that is almost 409 million years old from the Early Devonian (early Emsian) period of New Brunswick, Canada. The specimen, identified as Doliodus problematicus (Woodward), sheds light on the earliest chondrichthyans and their interrelationships with basal jawed vertebrates. This species has been truly problematic. Previously known only from isolated teeth, it has been identified as an acanthodian and a chondrichthyan. This specimen is the oldest shark showing the tooth families in situ, and preserves one of the oldest chondrichthyan braincases. More notably, it shows the presence of paired pectoral fin-spines, previously unknown in cartilaginous fishes.

  4. Book Bonding.

    ERIC Educational Resources Information Center

    Elleman, Barbara

    1998-01-01

    Discusses nine books (fiction, nonfiction, and poetry) for children that center on bats. Focuses on one book ("Silverwing") as an example of the animal fantasy genre, which can tell the adventures of a particular animal, impart environmental knowledge and concerns, and include intriguing, solid facts about the animal in question. Offers…

  5. Book Review.

    ERIC Educational Resources Information Center

    Christensen, Linda

    1994-01-01

    Reviews "Attention Deficit Disorder: ADHD and ADD Syndromes" (D. R. Jordan), a short book about the characteristics and differences between attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD) and the effect they have on children and adults in their classrooms, home, and workplace. The book includes techniques for…

  6. New Books.

    ERIC Educational Resources Information Center

    Streed, Sarah

    1998-01-01

    Relates a story of the author teaching English as a foreign language in Morocco--the excitement her students felt upon (1) being given books of great American short stories; (2) reading together a story from the book; and (3) feeling the power of literature at work. (SR)

  7. Book Review.

    ERIC Educational Resources Information Center

    Hargrave, Mary C.

    1993-01-01

    Reviews "Children and Youth in Limbo: A Search for Connections," a book by Nadia Ehrlich Finkelstein. The book develops a categorical scheme for providing care to children and adolescents in families with varying degrees of commitment and permanency, and stresses the need for youths to have and maintain "roots." (MDM)

  8. Book Reviews.

    ERIC Educational Resources Information Center

    Convergence, 1996

    1996-01-01

    This special book review section contains reviews of 18 books in adult and continuing education and development. Subjects include rural development, feminist discourse, group facilitation, Paulo Freire, professional development, social change, participatory action research, and the ecology of written language. (SK)

  9. Book Reviews.

    ERIC Educational Resources Information Center

    Powicke, J. C.; And Others

    1986-01-01

    Reviews of 10 recent books and one new journal ("Catalyst: A Journal of Policy Debate") are provided. Topics of the books reviewed include: economics in modern Britain, world economics, the mixed economy, Milton Friedman's thought, British industry, economic issues, and London as a financial center. (JDH)

  10. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.

    1994-01-01

    Reviews five books: "Garbage Pizza, Patchwork Quilts and Math Magic" (Ohanian), about elementary math instruction; "Ready for What?" (Graue), on school readiness; "The Braid of Literature: Children's Worlds of Reading" (Wolf and Heath); "The Best Years of Their Lives" (Zvirin), a book of resources for teenagers; and "Teaching and Learning in the…

  11. Book Reviews.

    ERIC Educational Resources Information Center

    Beveridge, Sally; And Others

    1993-01-01

    Reviews three books: (1) "Special Educational Needs in Schools" (Sally Beveridge), concerning the education of special needs children in Britain; (2) "Class Management" (E.C. Wragg), one of a series of practical resource books for primary school teachers; and (3) "Teaching Music in the Primary School" (Joanna Glover…

  12. Cassette Books.

    ERIC Educational Resources Information Center

    Library of Congress, Washington, DC. National Library Service for the Blind and Physically Handicapped.

    This catalog lists cassette books produced by the National Library Service for the Blind and Physically Handicapped during 1989. Books are listed alphabetically within subject categories under nonfiction and fiction headings. Nonfiction categories include: animals and wildlife, the arts, bestsellers, biography, blindness and physical handicaps,…

  13. Geologic and economic case histories of Upper Devonian natural gas production in Pennsylvania

    SciTech Connect

    Mangini, K.N.

    1988-08-01

    The Upper Devonian gas sands of western Pennsylvania have been commercially exploited since the turn of the century. The economic success of this exploitation may be attributed to the existence of multiply-stacked or en echelon reservoirs. The serendipity of development drilling coupled with multiple reservoirs made drilling for Upper Devonian gas very attractive to operators. As a result of many years of concentrated drilling, a current shortage of Upper Devonian developmental prospects exists and is forcing operators to explore nearshore more sporadically deposited Devonian sand reservoirs. The depositional modeling of developed areas can, however, help identify new prospective areas for exploration and development and increase economic success.

  14. Book Review

    PubMed Central

    Donev, Doncho

    2016-01-01

    PURPOSE: This book provides step-by-step guidance on developing a sound publication strategy for how to prepare and get research papers published. The book is a user-friendly guide, a route map for publishing that covers many topics, ranging from abstracts and blogs, tables and trial registration to ethical principles and conventions for writing scientific papers. Publishing the results of scientific research in the form of a scientific paper is the ultimate goal and the final stage of the research of each scientist. To write and publish papers is never going to be an easy task. With this book as their guide, researchers will be better informed and therefore should have an easier and altogether more pleasant path to publication with clear direction on how to choose the right journal, avoid publication delays, and resolve authorship disputes and many other problems associated with scientific publishing. CONTENTS: The 188 pages of the book are distributed in 5 chapters in Part I and 249 entries ordered by the letters of Alphabet in Part II creating an A to Z of publication strategy. In the Appendices there are four sections covering further reading, organizations, guidelines and principles of good publication practice for company-sponsored medical research. The book also contains key references and useful websites within many entries where it seemed helpful. The last ten pages of the book present an index to help users to find the information of interest in the book. CONCLUSION: The book is intended to help all authors, young and old, novice and experienced, to plan their research and publications effectively and prepare manuscripts for journals and other publications, increasing the likelihood that their work will be published. Providing essential information on publishing strategy and process, the book should be extremely useful to everyone who wants to publish research results.

  15. Nightmare book

    NASA Astrophysics Data System (ADS)

    judithku; jajustin; tyler, d.

    2017-02-01

    In response to Kate Brown's review of Kate Moore's book The Radium Girls, which tells the depressing but important tale of female radium-dial painters in the early 1900s who contracted radiation poisoning.

  16. Book Preservation

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Books produced since 1850, held in the Library of Congress, have a very high acid content, hence a shorter life expectancy than prior-published volumes. A means of "deacidifying" books on a large, economically-viable scale is of great interest, particularly to the research library community, which stores millions of valuable, often irreplaceable documents. The General Electric vacuum chamber used in deacidification tests serves a dual purpose. It creates an environment in which DEZ can do its job without presence of oxygen and also dries the books. After the drying phase, DEZ is introduced to the chamber as a paper-penetrating vapor. The complete process typically takes eight days, four days for vacuum drying and four days of book exposure to DEZ. Accelerated aging tests showed that the process can extend paper life almost fourfold, even on color illustrations.

  17. Book Reviews.

    ERIC Educational Resources Information Center

    Dodd, John M.; And Others

    1992-01-01

    Reviews two books on issues of Native American education: (1) "Light of the Feather: Pathways through Contemporary Indian America" (M. Fedullo); and (2) "Teaching American Indian Students" (J. Rehner). (ME)

  18. Reviews: Books.

    ERIC Educational Resources Information Center

    Weiss, Bretta; And Others

    1993-01-01

    Reviews three books: "The Schoolhome: Rethinking Schools for Changing Families," by Jane Martin; "Godly Play," by Jerome Berryman; and "Five Kingdoms: An Illustrated Guide to the Phyla of Life on Earth," by Margulis and Schwartz. (TJQ)

  19. Book Reviews

    NASA Astrophysics Data System (ADS)

    Baumeister, Phillip; Baumeister, Phillip

    1986-12-01

    This book hardly needs an introduction, since its first edition appeared 17 years ago. In the mid-1970s I was teaching a course on optical coatings to a group of optical coating engineers from various industrial coating shops. I chatted with engineers from Texas Instruments who had learned about optical coatings essentially on their own, with little tutoring from experienced workers. They referred to Prof. Macleod's book as their "bible." While this reviewer does not mean to imply any irreverent comparison, it still serves to remind us that Macleod's book has remained the standard textbook on optical coatings for nearly two decades. Other books have appeared during this period, for example, Z. Knittl's Optics of Thin Films and more recently H. Pulker's Coatings on Glass. Although they cover some topics that Macleod does not, Thin-Film Optical Filters has remained the standard reference and text in this field.

  20. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.

    1995-01-01

    Reviews five books on talk in the classroom; teaching with humor and play; how children talk, write, dance, draw, and sing their understanding of the world; talented teenagers; and life histories of women teachers working for social change. (BAC)

  1. Book Reviews.

    ERIC Educational Resources Information Center

    Dodd, John M.; And Others

    1992-01-01

    Reviews two books on issues of Native American education: (1) "Light of the Feather: Pathways through Contemporary Indian America" (M. Fedullo); and (2) "Teaching American Indian Students" (J. Rehner). (ME)

  2. Geology of the Devonian black shales of the Appalachian Basin

    USGS Publications Warehouse

    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.

  3. 18 CFR 270.303 - Natural gas produced from Devonian shale.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 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...

  4. 18 CFR 270.303 - Natural gas produced from Devonian shale.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 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...

  5. 18 CFR 270.303 - Natural gas produced from Devonian shale.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 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...

  6. 18 CFR 270.303 - Natural gas produced from Devonian shale.

    Code of Federal Regulations, 2010 CFR

    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...

  7. 18 CFR 270.303 - Natural gas produced from Devonian shale.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 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...

  8. Diagenesis of Coeymans (Lower Devonian) patch reefs, northern Appalachian basin

    SciTech Connect

    Precht, W.F.

    1984-12-01

    Fourteen Coeymans-age patch reefs and biotherms have been identified along the Silurian-Devonian outcrop belt in northeastern Pennsylvania, northwestern New Jersey, and central New York. Detailed petrographic analysis of samples from five reefs has led to development of a regional diagenetic model. The model developed in this study leads us to infer that Coeymans reefs found in the shallow subsurface would not be favorable hydrocarbon reservoirs. The possibility does exist that localized porosity development occurs in untested reefs within the deeper subsurface portions of the basin.

  9. Preliminary sensitivity analysis of the Devonian shale in Ohio

    SciTech Connect

    Covatch, G.L.

    1985-06-01

    A preliminary sensitivity analysis of gas reserves in Devonian shale in Ohio was made on the six partitioned areas, based on a payout time of 3 years. Data sets were obtained from Lewin and Associates for the six partitioned areas in Ohio and used as a base case for the METC sensitivity analysis. A total of five different well stimulation techniques were evaluated in both the METC and Lewin studies. The five techniques evaluated were borehole shooting, a small radial stimulation, a large radial stimulation, a small vertical fracture, and a large vertical fracture.

  10. A simple type of wood in two Early Devonian plants.

    PubMed

    Gerrienne, Philippe; Gensel, Patricia G; Strullu-Derrien, Christine; Lardeux, Hubert; Steemans, Philippe; Prestianni, Cyrille

    2011-08-12

    The advent of wood (secondary xylem) is a major event of the Paleozoic Era, facilitating the evolution of large perennial plants. The first steps of wood evolution are unknown. We describe two small Early Devonian (407 to 397 million years ago) plants with secondary xylem including simple rays. Their wood currently represents the earliest evidence of secondary growth in plants. The small size of the plants and the presence of thick-walled cortical cells confirm that wood early evolution was driven by hydraulic constraints rather than by the necessity of mechanical support for increasing height. The plants described here are most probably precursors of lignophytes.

  11. Study of explosive stimulation in Devonian-shale gas wells

    SciTech Connect

    Loving, F.A.; Simmons, W.J.

    1980-11-01

    A comparison of explosive treatments in eight Devonian shale wells in Union District, Putnam County, WV is presented. Intervals of about 600 ft were shot with (1) 5-inch-diameter gelatin dynamite (6000 lb in 6-1/4 inch hole), (2) EL836 aluminized water gel explosive (12,000 lb in 6-1/4 inch hole) and (3) EL836 in an underreamed hole (37,500 lb in a 12-inch hole). Final open-flow data after treatment indicate substantially larger gas flows from the heavier charge-per-foot treatments. 2 figures, 2 tables.

  12. Book Reviews

    PubMed Central

    2014-01-01

    Richard P. Di Fabio, Essentials of Rehabilitation Research: A Statistical Guide to Clinical Practice, reviewed by Laura Desveaux Jason Brumitt, Physical Therapy Case Files: Orthopaedics, reviewed by Maria Lung

  13. Unsuspected functional disparity in Devonian fishes revealed by tooth morphometrics?

    NASA Astrophysics Data System (ADS)

    Gauchey, Samuel; Girard, Catherine; Adnet, Sylvain; Renaud, Sabrina

    2014-09-01

    The shape of features involved in key biological functions, such as teeth in nutrition, can provide insights into ecological processes even in ancient time, by linking the occupation of the morphological space (disparity) to the occupation of the ecological space. Investigating disparity in radiating groups may provide insights into the ecological diversification underlying evolution of morphological diversity. Actinopterygian fishes initiated their radiation in the Devonian, a period characterized by the diversification of marine ecosystem. Although a former morpho-functional analysis of jaw shape concluded to conservative and poorly diversified morphologies in this early part of their history, fish tooth disparity evidenced here an unsuspected diversity of possible functional significance in the pivotal period of the Late Devonian (Famennian). All teeth being caniniforms, some were stocky and robust, in agreement with expectations for active generalist predators. More surprisingly, elongated teeth also occurred at the beginning of Famennian. Their needle-like shape challenges morpho-functional interpretations by making them fragile in response to bending or torsion. The occurrence of both types of fish teeth during the beginning of the Famennian points to a discrete but real increase in disparity, thus testifying a first burst of feeding specialization despite overall conservative jaw morphology. The disappearance of these needle-like teeth in the Late Famennian might have been related to a relay in dental diversity with abundant co-occurring groups, namely conodonts and chondrichthyans (sharks).

  14. Putative cryptoendolithic life in Devonian pillow basalt, Rheinisches Schiefergebirge, Germany.

    PubMed

    Peckmann, J; Bach, W; Behrens, K; Reitner, J

    2008-03-01

    Middle Devonian (Givetian) pillow basalt and inter-pillow breccia from the Rheinisches Schiefergebirge in Germany were found to contain putative biogenic filaments that indicate that life once proliferated within these volcanic rocks. Mineralized filaments are found in carbonate amygdules (vesicles filled by carbonate cement) in the volcanic rock, where they started to form on the internal surface of the once water-filled vesicles. Biogenicity of the filaments is indicated by (1) their size and shape resembling modern microorganisms including a constant diameter along the length of curved filaments, (2) their independence of crystal faces or cleavage planes, (3) branching patterns reminiscent of modern microorganisms, and (4) their spatial clustering and preferential occurrence close to the margin of pillows and in the inter-pillow breccias. A time lag between the deposition of pillow basalt and the activity of endoliths is revealed by the sequence of carbonate cements filling the amygdules. The putative filamentous microorganisms thrived after the formation of early fibrous rim cement, but before later equant calcite spar filled most of the remaining porosity. Microbial clay authigenesis analogous to the encrustation of prokaryotes in modern iron-rich environments led to the preservation of filaments. The filaments predominantly consist of the clay minerals chamosite and illite. Having dwelled in water-filled vesicles, the Devonian basalt-hosted filaments apparently represent cryptoendoliths. This finding suggests that a previously unrecognized niche for life exists within volcanic rock.

  15. Upper Devonian microvertebrates from the Canning Basin, Western Australia

    NASA Astrophysics Data System (ADS)

    Roelofs, Brett; Playton, Ted; Barham, Milo; Trinajstic, Kate

    2015-03-01

    A diverse microvertebrate fauna is described from the Virgin Hills and Napier formations, Bugle Gap Limestone Canning Basin, Western Australia. Measured sections at Horse Spring and Casey Falls (Virgin Hills Formation) and South Oscar Range (Napier Formation) comprise proximal to distal slope carbonates ranging in age from the Late Devonian Frasnian to middle Famennian. A total of 18 chondrichthyan taxa are identified based on teeth, including the first record of Thrinacodus tranquillus, Cladoides wildungensis, Protacrodus serra and Lissodus lusavorichi from the Canning Basin. A new species, Diademodus dominicus sp. nov. is also described and provides the first record of this genus outside of Laurussia. In addition, the upper range of Australolepis seddoni has been extended to Late Devonian conodont Zone 11, making it the youngest known occurrence for this species. The Virgin Hills and Napier formations microvertebrate faunas show close affinities to faunas recovered from other areas of Gondwana, including eastern Australia, Iran, Morocco and South China, which is consistent with known conodont and trilobite faunas of the same age.

  16. Affinities and architecture of Devonian trunks of Prototaxites loganii.

    PubMed

    Retallack, G J; Landing, Ed

    2014-01-01

    Devonian fossil logs of Prototaxites loganii have been considered kelp-like aquatic algae, rolled up carpets of liverworts, enormous saprophytic fungal fruiting bodies or giant lichens. Algae and rolled liverwort models cannot explain the proportions and branching described here of a complete fossil of Prototaxites loganii from the Middle Devonian (386 Ma) Bellvale Sandstone on Schunnemunk Mountain, eastern New York. The "Schunnemunk tree" was 8.83 m long and had six branches, each about 1 m long and 9 cm diam, on the upper 1.2 m of the main axis. The coalified outermost layer of the Schunnemunk trunk and branches have isotopic compositions (δ(13)CPDB) of -25.03 ± 0.13‰ and -26.17 ± 0.69‰, respectively. The outermost part of the trunk has poorly preserved invaginations above cortical nests of coccoid cells embraced by much-branched tubular cells. This histology is unlike algae, liverworts or vascular plants and most like lichen with coccoid chlorophyte phycobionts. Prototaxites has been placed within Basidiomycota but lacks clear dikaryan features. Prototaxites and its extinct order Nematophytales may belong within Mucoromycotina or Glomeromycota.

  17. Book Review

    NASA Astrophysics Data System (ADS)

    Bokulich, Alisa

    In recent years, there has been a growing resurgence of interest in the philosophical views of the founders of quantum mechanics. Kristian Camilleri's book on Werner Heisenberg's philosophy of quantum mechanics is a welcome addition to this literature. It takes Heisenberg seriously as a philosopher of science, traces the various philosophical influences on his view, and carefully distinguishes his interpretation of quantum mechanics from that of his contemporaries. It is a fine example of the new insights that can emerge when one takes an integrated approach to the history and philosophy of science. After summarizing some of the main themes of the book, I will turn to two moderate criticisms of the book-one stylistic, and the other, regarding its content.

  18. Building Relationships (Children's Books).

    ERIC Educational Resources Information Center

    Galda, Lee

    1991-01-01

    Reviews 44 trade books that focus on the relationships between families and friends. Offers an annotated bibliography on dinosaurs including 15 primary level books, 14 intermediate level books, 7 intermediate to advanced level books, and 2 advanced level books. (MG)

  19. Book Review

    NASA Astrophysics Data System (ADS)

    Mishchenko, Michael I.

    2016-08-01

    The main purpose of this exemplary book is to provide a systematic exposition of the entire field of optical tweezers and their applications. The book is divided into three (approximately equal) parts summarizing the electromagnetic theory of optical tweezers (Part I), the practice of designing and building optical tweezers (Part II), and extensive applications of optical tweezers in various branches of science (Part III). The exposition is highly methodical and addresses the needs of anyone dealing with optical tweezers, be it a theoretician, an engineer/experimentalist, a routine practitioner, or an interested scientist.

  20. Book Review

    NASA Astrophysics Data System (ADS)

    Fritz, Steffen

    2017-07-01

    The book titled European Landscape Dynamics is a comprehensive compendium on the European CORINE land cover (CLC) and some other aspects such as fragmentation and ecosystem services in Europe. The authors constitute a wide selection of researchers and practitioners from across Europe active in this field. It contains 29 chapters of very different sizes ranging between 2 pages (Chapter 8) to 43 pages (Chapter 20). The book is structured in 5 different sections: 1. Introduction; 2. Methodology; 3. European CORINE data layers; 4. Case studies; and 5. CORINE Land Cover Perspective.

  1. Book Review

    NASA Astrophysics Data System (ADS)

    Clevers, J. G. P. W.

    2015-02-01

    About thirty years after the previous advanced textbook on Microwave Remote Sensing by Ulaby, Moore and Fung has been published as three separate volumes, now an up-to-date new textbook has been published. The 1000-page book covers theoretical models, system design and operation, and geoscientific applications of active and passive microwave remote sensing systems. It is designed as a textbook at the postgraduate level, as well as a reference for the practicing professional. The book is caught by a thorough introduction into the physics and mathematics of electrical engineering applied to microwave radiation. Here on overview of its chapters with a short description of its focus will be given.

  2. Book Review:

    NASA Astrophysics Data System (ADS)

    Botet, R.

    2004-09-01

    The second edition of Mathematical Methods for Physics and Engineering by Riley et al is a great scientific textbook. The reader should not be intimidated by its size - over 1200 pages - and skimming through it, one is confronted with a vast amount of information (which could be daunting for students). However, when reading it in detail one realizes that the number of pages is justified and the result is a self-contained reference on mathematical methods for physics. The book is well organized: it starts at basic university undergraduate level and progresses to the highest graduate level. It is a tour de force to write mathematical sections that are both complete and at a appropriate academic level; the sequence of sections (and their content) has been chosen with great care in order that each section may introduce the following ones. The authors have clearly succeeded with this challenge, making this a remarkable pedagogical book. No precise knowledge is needed at the beginning, and all the material is presented in a logical progression. The student can confidently follow the material as it is presented. Even though this book is devoted to physics and engineering, it can be used by students in other scientific fields. The material covered in the book concentrates on applied theorems and formulae. But as the title of the book indicates, it is primarily written 'for physics and engineering' so this is to be expected and it greatly simplifies the text of the course. Consequently, derivations of the main results are essentially 'for physicists'. Frequently proofs are briefly outlined and are not as detailed as many mathematicians would like. Nevertheless, the final results are always clearly stated together with the technical conditions under which they should be used, thus providing a very comprehensive and practical textbook. The only criticism is that the sections on probability and statistics do not fit comfortably between their previous and following sections

  3. A new ischnacanthiform (Acanthodii) from the latest Devonian of Iran and the palaeogeography of Late Devonian ischnacanthiforms

    NASA Astrophysics Data System (ADS)

    Hairapetian, Vachik; Burrow, Carole J.

    2016-07-01

    Dentigerous jaw bones from the Bahram Formation (Late Devonian) near Chahriseh, Iran represent the second youngest record of ischnacanthiform acanthodians worldwide. The specimens are assigned to Atopacanthus based on the near symmetrical shape of the lateral teeth, lack of side cusps on these teeth, and the low angle at which the posterior flange diverges from the longitudinal axis of the bone. They are assigned to a new species Atopacanthus juvai based on the unique combination of a lingual row of rounded teeth, a single row of small denticles on the medial ridge between the lateral and lingual tooth rows, and larger rounded denticles along the base of the lateral teeth lingually. The genus Atopacanthus is otherwise only known from Frasnian marine deposits in the U.S.A., Spitzbergen, Russia, and Germany. The closely related genus Persacanthus is found in the Frasnian of the U.S.A., Canada, Russia, and central Iran. These occurrences indicate possible two-way dispersal between Northern Gondwana and Laurussia in the Late Devonian.

  4. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.; And Others

    1993-01-01

    Reviews six books: "Teacher Lore" (Schubert and Ayers), about teachers' accounts of their experience; "America's Best Classrooms" (Seymour and others); "Another Door to Learning," (Schwarz) about learning-disabled children; "Talking with Your Children about a Troubled World" (Dumas); "Our Family, Our…

  5. Book Reviews.

    ERIC Educational Resources Information Center

    Campbell, James J.; Sullivan, Ann

    1994-01-01

    Reviews two books: (1) "LEAD!" (Richard Lynch), which outlines leadership principles for nonprofit and public agency managers; and (2) "Troubled Transplants: Unconventional Strategies for Helping Disturbed Foster and Adopted Children" (Richard J. Delaney and Frank R. Kunstal), which offers practical suggestions for intervention by parents and…

  6. Distinguished Books.

    ERIC Educational Resources Information Center

    Maryles, Daisy; Roback, Diane; Ink, Gary

    2001-01-01

    Includes 12 articles that list notable books for college-bound youth, young adults, and children; paperbacks for young adults; audiobooks for young adults; children's videos; recordings for children; software and Web sites for children; bestsellers of 2000; and literary prizes that were awarded in 2000. (LRW)

  7. Electronic Books

    ERIC Educational Resources Information Center

    Clyde, Laurel A.

    2005-01-01

    Terje Hillesund points out that "information technology and especially the Internet have profoundly changed the ways of publishing." Recently, the book publishing industry has started to catch up, making digitized texts--including multimedia texts--available for sale through online bookstores, and in some cases, available for free downloading.…

  8. Digital books.

    PubMed

    Wink, Diane M

    2011-01-01

    In this bimonthly series, the author examines how nurse educators can use the Internet and Web-based computer technologies such as search, communication, and collaborative writing tools; social networking and social bookmarking sites; virtual worlds; and Web-based teaching and learning programs. This article describes digital books.

  9. Book Reviews.

    ERIC Educational Resources Information Center

    Hershfield, Bruce; DeWoody, Madelyn

    1993-01-01

    Reviews two booklets edited by Kay Albrecht and by Albrecht and Margaret Plantz that outline principles of developmentally appropriate practices and criteria for quality in child care programs. Also reviews a book by John Meyers that guides helping professionals through the language, themes, rules, and roles of the legal system as the system…

  10. Book Reviews.

    ERIC Educational Resources Information Center

    Campbell, James J.; Sullivan, Ann

    1994-01-01

    Reviews two books: (1) "LEAD!" (Richard Lynch), which outlines leadership principles for nonprofit and public agency managers; and (2) "Troubled Transplants: Unconventional Strategies for Helping Disturbed Foster and Adopted Children" (Richard J. Delaney and Frank R. Kunstal), which offers practical suggestions for intervention by parents and…

  11. Book Reviews.

    ERIC Educational Resources Information Center

    Fein, Greta G.; And Others

    1993-01-01

    Reviews the following books: "Child Care in Context" (Lamb et al., Eds.); "Making Friends in School: Promoting Relationships in Early Childhood" (Ramsay); "The Epigenesis of Mind: Essays on Biology and Cognition" (Carey and Gelman, Eds.); "Moral Maturity: Measuring the Development of Sociomoral Reflection"…

  12. Book Briefs.

    ERIC Educational Resources Information Center

    Child Welfare, 1993

    1993-01-01

    Briefly reviews seven books on the following topics: (1) runaway and homeless youth; (2) drug abuse prevention; (3) issues related to helping children prenatally exposed to drugs and alcohol; (4) lesbians and gay men as foster parents; (5) a multicultural approach to child welfare; (6) keys to successful volunteer programs; and (7) single mothers.…

  13. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.

    1994-01-01

    Reviews five books for educators: (1) "Once upon a Folktale: Capturing the Folklore Process with Children" (Blatt); (2) "Integrated Studies in the Middle Grades: Dancing through Walls" (Stevenson, Carr); (3) "Conflict in Child and Adolescent Development" (Schantz, Hartup); (4) "Ways of Assessing Children and…

  14. Electronic Books

    ERIC Educational Resources Information Center

    Clyde, Laurel A.

    2005-01-01

    Terje Hillesund points out that "information technology and especially the Internet have profoundly changed the ways of publishing." Recently, the book publishing industry has started to catch up, making digitized texts--including multimedia texts--available for sale through online bookstores, and in some cases, available for free downloading.…

  15. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.

    1994-01-01

    Reviews four professional books: (1) "Changing Teaching, Changing Schools. Bringing Early Childhood Practice into Public Education: Case Studies from the Kindergarten" (O'Connell); (2) "Whole Language Plus: Essays on Literacy in the United States and New Zealand" (Cazden); (3) "Audacious Kids: Coming of Age in America's…

  16. Book Reviews.

    ERIC Educational Resources Information Center

    Sinnott, Jan D.; And Others

    1995-01-01

    Reviews four books: (1) "A Dynamic Systems Approach to Development: Applications" (Linda B. Smith and Esther Thelen, Eds.); (2) "The Psychology of Gender" (Anne E. Beall and Robert J. Sternberg, Eds.); (3) "Children's Understanding: The Development of Mental Models" (Graeme S. Halford); and (4) "Adolescent Storm…

  17. Book Reviews.

    ERIC Educational Resources Information Center

    Eron, Leonard D.; And Others

    1994-01-01

    Reviews six books on developmental psychology: (1) "Children and Violence" (David Reiss and others); (2) "Television and the American Child" (George Comstock); (3) "Intellectual Development" (Robert Sternberg and Cynthia Berg); (4) "Context and Development" (Robert Cohen and Alexander Siegel); (5) "Adolescent Identity Formation" (Gerald Adams and…

  18. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.; And Others

    1993-01-01

    Reviews six books: "Teacher Lore" (Schubert and Ayers), about teachers' accounts of their experience; "America's Best Classrooms" (Seymour and others); "Another Door to Learning," (Schwarz) about learning-disabled children; "Talking with Your Children about a Troubled World" (Dumas); "Our Family, Our…

  19. Book Reviews

    ERIC Educational Resources Information Center

    Holeinger, Philip R.; And Others

    1986-01-01

    Presents and review six books. Topics include earth science topics (Philip R. Holzinger, 1985), the wild horse controversy (Richard Symanski, 1985), historical Dutch geography (Audrey M. Lambert, 1985), urban geography (Susan L. Cutter, 1985), a geopolitical atlas (Gerard Chaliand and Jean-Pierre Rageau, 1985), and remote sensing (Robert K. Holz,…

  20. Book Reviews

    ERIC Educational Resources Information Center

    Holeinger, Philip R.; And Others

    1986-01-01

    Presents and review six books. Topics include earth science topics (Philip R. Holzinger, 1985), the wild horse controversy (Richard Symanski, 1985), historical Dutch geography (Audrey M. Lambert, 1985), urban geography (Susan L. Cutter, 1985), a geopolitical atlas (Gerard Chaliand and Jean-Pierre Rageau, 1985), and remote sensing (Robert K. Holz,…

  1. Book Reviews.

    ERIC Educational Resources Information Center

    Pencek, Bruce; And Others

    1986-01-01

    Reviews of five books are presented. Topics are public property and private power (Hartog, 1983), essays on Julius Caesar (Blits, 1982), changes in the American political system (Shafer, 1983), the spiritual crisis in western civilizations (Harrington, 1983), and justice, pluralism and equality (Walzer, 1983). (JDH)

  2. Book Reviews.

    ERIC Educational Resources Information Center

    Pencek, Bruce; And Others

    1986-01-01

    Reviews of five books are presented. Topics are public property and private power (Hartog, 1983), essays on Julius Caesar (Blits, 1982), changes in the American political system (Shafer, 1983), the spiritual crisis in western civilizations (Harrington, 1983), and justice, pluralism and equality (Walzer, 1983). (JDH)

  3. Professional Books.

    ERIC Educational Resources Information Center

    Gilstrap, Robert L.; And Others

    1994-01-01

    Reviews five books peace studies and conflict resolution: (1) "Voices from the Future" (Susan Goodwillie); (2) "War and Peace Literature for Children and Young Adults" (Virginia Walter); (3) "Teaching Young Children in Violent Times" (Diane Levin); (4) "Whose Language? What Power?" (Frank Smith); and (5)…

  4. Book Reviews.

    ERIC Educational Resources Information Center

    Joyner, Christopher C.; And Others

    1986-01-01

    Scholarly reviews of nine books are presented. Topics include nuclear deterrence, urban planning in France, human rights in the Republic of China, the United States' support of Israel, U. S. military policy, an analysis of Rousseau's social contract, political influences on the U. S. presidency, the state and political theory, and the loss of…

  5. Book Reviews.

    ERIC Educational Resources Information Center

    Eron, Leonard D.; And Others

    1994-01-01

    Reviews six books on developmental psychology: (1) "Children and Violence" (David Reiss and others); (2) "Television and the American Child" (George Comstock); (3) "Intellectual Development" (Robert Sternberg and Cynthia Berg); (4) "Context and Development" (Robert Cohen and Alexander Siegel); (5) "Adolescent Identity Formation" (Gerald Adams and…

  6. Book Review.

    ERIC Educational Resources Information Center

    Pecora, Peter J.; Cline, Stephanie

    1994-01-01

    Reviews two books: (1) "Advancing Family Preservation Practice" (E. Susan Morton and R. Kevin Brigsby, editors) which summarizes Intensive Family Preservation Services in the United States over the past decade; and (2) "Marketing Strategies for Nonprofit Organizations" (Siri Espy) which discusses marketing and its application…

  7. Book Review:

    NASA Astrophysics Data System (ADS)

    Fallone, B. G.

    2004-01-01

    This book represents the proceedings of the five day programme on IMRT techniques presented at the 2003 American Association of Physicists in Medicine (AAPM) Summer School held in Colorado Springs, Colorado. The book is essentially an overview of IMRT techniques, discussing the history, the mathematical processes involved in the planning stages, the biological indices for evaluations, the off-line and on-line medical imaging that is required, the various IMRT delivery techniques available, positioning and motion verification, shielding and QA issues, and some clinical applications. There is some additional discussion on modulated electron and proton therapy, views on the clinical and financial impact of IMRT, as well as some speculation on the future uses of IMRT. The fact that the book is an `overview' must be emphasized. Medical physicists who are well-read in IMRT, or have implemented IMRT, even partially, may be a little disappointed with the book. Although specific details were purposely omitted, the well-read physicist would have preferred to go right to the `heart of the matter', something this book fails to do. As is typical of many proceedings-type books, there is a certain level of inconsistency of writing styles, as well as some redundancy between the different chapters. It is unfortunate that such a large volume does not have an index to allow a reader to explore a particular subject pertaining to IMRT. The reader would have to guide himself/herself by the table of contents before each chapter which could be a problem if the reader requires some information quickly. It is interesting to note that the book lends itself to a variety of professionals interested in IMRT, including administrators. It may be a source of help for medical physicists who wish to discuss IMRT issues with higher level administration, for example. Some clinical applications are also reviewed. The lack of details concerning the advantages of IMRT with respect to clinical outcome is

  8. Thermal maturity map of Devonian shale in the Illinois, Michigan, and Appalachian basins of North America

    USGS Publications Warehouse

    East, Joseph A.; Swezey, Christopher S.; Repetski, John E.; Hayba, Daniel O.

    2012-01-01

    Much of the oil and gas in the Illinois, Michigan, and Appalachian basins of eastern North America is thought to be derived from Devonian shale that is within these basins (for example, Milici and others, 2003; Swezey, 2002, 2008, 2009; Swezey and others, 2005, 2007). As the Devonian strata were buried by younger sediments, the Devonian shale was subjected to great temperature and pressure, and in some areas the shale crossed a thermal maturity threshold and began to generate oil. With increasing burial (increasing temperature and pressure), some of this oil-generating shale crossed another thermal maturity threshold and began to generate natural gas. Knowledge of the thermal maturity of the Devonian shale is therefore useful for predicting the occurrence and the spatial distribution of oil and gas within these three basins. This publication presents a thermal maturity map of Devonian shale in the Illinois, Michigan, and Appalachian basins. The map shows outlines of the three basins (dashed black lines) and an outline of Devonian shale (solid black lines). The basin outlines are compiled from Thomas and others (1989) and Swezey (2008, 2009). The outline of Devonian shale is a compilation from Freeman (1978), Thomas and others (1989), de Witt and others (1993), Dart (1995), Nicholson and others (2004), Dicken and others (2005a,b), and Stoeser and others (2005).

  9. Analysis of eastern Devonian gas shales production data. Annual report, July 1, 1984-June 30, 1985

    SciTech Connect

    Gatens, J.M.; Lee, W.J.

    1985-07-01

    Production data from over 500 eastern Devonian Shale gas wells were analyzed to determine reservoir characteristics, identify reservoir characteristics that correlate with well quality, develop analytical tools for studying the Devonian Shales, and study effects of stimulation methods on well quality. Empirical equations, production type curves, and an analytical history-matching scheme were developed to determine reservoir characteristics and predict performance. Preliminary stimulation analysis shows that vertical hydraulic fracturing is the optimal stimulation method in the Devonian Shales if created fractures intersect high-permeability features. If not, radial fracturing may be optimal, assuming sufficient fracture length and conductivity can be achieved in practice.

  10. Book Review:

    NASA Astrophysics Data System (ADS)

    Chrusciel, P. T.

    2006-06-01

    Most of us sometimes have to face a student asking: 'What do I need to get started on this'. (In my case 'this' would typically be a topic in general relativity.) After thinking about it for quite a while, and consulting candidate texts again and again, a few days later I usually end up saying: read this chapter in book I (but without going too much detail), then that chapter in book II (but ignore all those comments), then the first few sections of this review paper (but do not try to work out equations NN to NNN), and then come back to see me. In the unlikely event that the student comes back without changing the topic, there follows quite a bit of explaining on a blackboard over the following weeks. From now on I will say: get acquainted with the material covered by this book. As far as Isham's book is concerned, 'this' in the student's question above can stand for any topic in theoretical physics which touches upon differential geometry (and I can only think of very few which do not). Said plainly: this book contains most of the introductory material necessary to get started in general relativity, or those branches of mathematical physics which require differential geometry. A student who has mastered the notions presented in the book will have a solid basis to continue into specialized topics. I am not aware of any other book which would be as useful as this one in terms of the spectrum of topics covered, stopping at the right place to get sufficient introductory insight. According to the publisher, these lecture notes are the content of an introductory course on differential geometry which is taken by first-year theoretical physics PhD students, or by students attending the one-year MSc course 'Quantum Fields and Fundamental Forces' at Imperial College, London. The volume is divided into six chapters: An Introduction to Topology Differential Manifolds Vector Fields and n-Forms Lie Groups Fibre Bundles Connections in a Bundle. It is a sad reflection on current

  11. Devonian palaeobiogeographic affinities of Afghanistan and surrounding areas (Iran, Pakistan)

    NASA Astrophysics Data System (ADS)

    Mistiaen, B.; Brice, D.; Hubert, B. L. M.; Pinte, E.

    2015-04-01

    Palaeozoic (Devonian) outcrops in Afghanistan and neighbouring countries (Iran, Pakistan) are numerous but very sparsely distributed, and poorly known. The first interpretation, based on rare or poor data considered these North Gondwanan terranes as poorly connected and some authors have suggested the presence of large oceanic domains in palaeogeographical models. Increase in knowledge, especially of the distribution of main fossils groups, and also some lithological similarities, allow a review of the preliminary models and the identification of connections between the different terranes. For example the presence of Fistuliporid Bryozoan beds or rich Receptaculites levels in different sections of the three countries, especially in the Dasht-e Nawar and Central Iran areas, allows the preliminary models to be reviewed and the connections among the different terranes to be clarified.

  12. Osmium isotopes and the Upper Devonian "Kellwasser" event

    NASA Astrophysics Data System (ADS)

    Brauns, M.

    2001-12-01

    The Upper Devonian "Kellwasser" horizon at the Frasnian/Famennian boundary (~367 Ma) records one of the most severe world-wide catastrophic bio-events in Earth's history. Current theories for the causes of mass extinction include (e.g. Schindler 1990) (i) meteoritic impact, (ii) sea-level changes, shifts of the sedimentary realm and generation of anoxic milieus, (iii) enhanced clastic input and modification of sea water chemistry, and, possibly, (iv) a combination of (ii) and (iii). The time-integrated Os isotopic composition of Kellwasser limestones appears to be a suitable tool to shed light on these options and possibly place constraints on the Os isotopic evolution of Upper Devonian sea water. We present complete Re-Os analyses of limestone and shale whole rock samples, and some biogenic/diagenetic constituents (conodonts, Fe oxides). The results indicate extreme Re and Os compositional variations between different limestone and shale sublayers (Re = 0.1 - 40 ppb, Os 26 - 830 ppt, Re/Os = 4 - 240). The present Os isotopic ratios of the rocks were found to be very radiogenic (187Os/186Os = 9,865 - 388,35). For the first time, conodont samples extracted from the Kellwasser sequence were tested as potential tracers for the Os isotopic composition of Upper Devonian sea water. Their Os contents are in the range of 210 - 112 ppt, which required analysis of about 15.000 specimens per sample to obtain sufficient Os for mass spectrometry. The Os of the conodonts (187Os/186Os = 14,35 - 67,89) is significantly less radiogenic compared to their complementary host rocks. Their 187Re/186Os, however, exceed the 187Re/186Os ratios of the host limestones by at least 1-2 orders of magnitude. Recalculation of the 187Re/186Os ratios of all rock and conodont samples for an age of 367 Ma yielded in all cases unrealistic and very contrasting values with respect to any hypothetical Os isotopic composition of Upper Devonian sea water. Our Re-Os isotopic data do establish several points

  13. Book Review

    NASA Astrophysics Data System (ADS)

    Tanona, Scott

    There is more to this book than readers of this journal might expect from an author who has associated Bohr and Heisenberg with Derrida and Lacan (Plotnitsky, 1994, 2002). Plotnitsky has written in the past on trying to bridge the "two cultures" of the "science wars" by defending Derrida and others against what he perceives to have been too-quickly dismissive critiques (Plotnitsky, 1997), but he has not provided an extended philosophical analysis of Bohr to support the connections he has made. This book seems to be an attempt to engage in a careful analysis of Bohr in a way meant to satisfy critical readers and also support what he here calls "nonclassical epistemology".

  14. Book Review

    NASA Astrophysics Data System (ADS)

    Giere, Ronald

    The original motivation for this book was to understand why the role of models in science was mostly ignored by philosophers of science for the first half of the twentieth century only to become the focus of much attention later in the second half of the century. The scope of the book, however, is much broader than that question. After a brief introductory chapter, there are chapters, respectively, on the use of mechanical models by scientists in the nineteenth century, the nature of analogy, the distinction between models and theories, paradigms and metaphors, the semantic view of theories, the distinctions among phenomena, data and data models, and, finally, representation using models. Overall, the volume is best described as an analytical history of the topic of models in the philosophy of science, a genre invoked by the author herself. (ix)

  15. Book Review

    NASA Astrophysics Data System (ADS)

    Gardonio, Paolo

    2016-01-01

    The content of this book is aptly depicted by its engaging cover design, which exemplifies the vast range of circumstances where sound and vibration characterise the life of human beings and animals, the environment, the quality of buildings and halls, the operation and comfort of land, water and air transportation vehicles, the functioning of machines, etc. Also, the short and comprehensive title effectively defines the breath (sound and vibration) and depth (fundamentals) of the covered topics.

  16. Book Review:

    NASA Astrophysics Data System (ADS)

    Combescure, M.

    2005-06-01

    This book provides an introduction and discussion of the main issues in the current understanding of classical Hamiltonian chaos, and of its fractional space-time structure. It also develops the most complex and open problems in this context, and provides a set of possible applications of these notions to some fundamental questions of dynamics: complexity and entropy of systems, foundation of classical statistical physics on the basis of chaos theory, and so on. Starting with an introduction of the basic principles of the Hamiltonian theory of chaos, the book covers many topics that can be found elsewhere in the literature, but which are collected here for the readers' convenience. In the last three parts, the author develops topics which are not typically included in the standard textbooks; among them are: the failure of the traditional description of chaotic dynamics in terms of diffusion equations; he fractional kinematics, its foundation and renormalization group analysis; `pseudo-chaos', i.e. kinetics of systems with weak mixing and zero Lyapunov exponents; directional complexity and entropy. The purpose of this book is to provide reearchers and students in physics, mathematics and engeenering with an overview of many aspects of chaos and fractality in Hamiltonian dynamical systems. In my opinion it achieves this aim, at least provided researchers and students (mainly those involved in mathematical physics) can complement this reading with comprehensive material from more specialized sources which are provided as references and `further reading'. Each section contains introductory pedagogical material, often illustrated by figures coming from several numerical simulations which give the feeling of what's going on, and thus is very useful to the reader who is not very familiar with the topics presented. Some problems are included at the end of most sections to help the reader to go deeper into the subject. My one regret is that the book does not mention the

  17. Book Review

    NASA Astrophysics Data System (ADS)

    Belot, Gordon; Jansson, Lina

    What is the relation between classical and quantum mechanics? Bokulich's fascinating Reexamining the Quantum-Classical Relation: Beyond Reductionism and Pluralism is devoted to this question. It is a remarkable book, deeply thoughtful, written with admirable clarity, and full of interesting ideas. It should be read by anyone with an interest in the history or philosophy of quantum theory or in relations between scientific theories.

  18. Devonian Winnipegosis reefs of Manitoba outcrop belt - possible basin model

    SciTech Connect

    McCabe, H.R.

    1988-07-01

    Devonian Winnipegosis reefs crop out intermittently along a 350-km belt in southwestern Manitoba and represent an almost complete facies sequence ranging from central-basin reefs in the northwest to shelf-edge reefs in the southeast. In addition, structural complexities of the overlying Devonian strata mirror precisely the configuration of the underlying reefs. These outcrop data, supplemented by closely spaced stratigraphic core holes that have been sited specifically with respect to reef-controlled structures, permit development of a tentative reef model. Reef parameters are (a) size, from less than 0.5 km to a maximum of about 12 km; (b) shape, small pinnacle-type features to broad, irregular, flat-topped, atoll-like complexes, all with relatively steep margins (5/degrees/-20/degrees/); and (c) height, uniform in any given area, ranging from 40-50 m at shelf edge to 65-90 m in central basin areas. Internal reef structure shows flat central beds, and flank dips ranging from 20/degrees/ to 45/degrees/ or more in the most basinward reefs. Locally, reefs are abundantly fossiliferous, but organic framework is difficult to identify. Black bituminous mudstones in the interreef and reef-flank areas, with or without reef-derived carbonate detritus, are the only time-stratigraphic equivalents of the reefs. (The Ratner-type bituminous carbonate laminites appear to entirely postdate reef development.) Configuration of the steep-sided reefs and the well-defined shelf edge may have been controlled not only by organic (biohermal.) development, but also by anoxic containment resulting from restriction of lateral growth by anoxic bottom waters. Pinnacle reefs could thus have developed, in part, as anoxically contained pinnacle mounds rather than true bioherms.

  19. Book Review:

    NASA Astrophysics Data System (ADS)

    Dray, T.

    2005-10-01

    I have had a love/hate relationship with this book ever since it first came out. On the one hand, this is an excellent introduction for mathematicians to the differential geometry underlying general relativity. On the other hand, this is definitely a book for mathematicians. The book's greatest strength is its clear, precise presentation of the basic ideas in differential geometry, combined with equally clear and precise applications to theoretical physics, notably general relativity. But the book's precision is also its greatest weakness; this is not an easy book to read for non-mathematicians, who may not appreciate the notational complexity, some of which is nonstandard. The present edition is very similar to the original, published in 1992. In addition to minor revisions and clarifications of the material, there is now a brief introduction to fibre bundles, and a (very) brief discussion of the gauge theory description of fundamental particles. The index to the symbols used is also a more complete than in the past, but without the descriptive material present in the previous edition. The bulk of the book consists of a careful introduction to tensors and their properties. Tensors are introduced first as linear maps on vector spaces, and only later generalized to tensor fields on manifolds. The differentiation and integration of differential forms is discussed in detail, including Stokes' theorem, Lie differentiation and Hodge duality, and connections, curvature and torsion. To this point, Wasserman's text can be viewed as an expanded version of Bishop and Goldberg's classic text [1], one major difference being Wasserman's inclusion of the pseudo-Riemannian case from the beginning (in particular, when discussing Hodge duality). Whether one prefers Wasserman's approach to Bishop and Goldberg's is largely a matter of taste: Wasserman's treatment is both more complete and more precise, making it easier to check calculations in detail, but occasionally more difficult

  20. Book Review:

    NASA Astrophysics Data System (ADS)

    Folacci, Antoine; Jensen, Bruce

    2003-12-01

    Thanks to its impressive success in the second half of the 20th century, both in high-energy physics and in critical phenomena, quantum field theory has enjoyed an abundant literature. We therefore greet yet another book on this subject with caution: what can a monograph on quantum field theory bring now that is new, either conceptually or pedagogically? But when it is written by a physicist such as Bryce DeWitt, who has made his own contribution to the collection of field theory books with The Global Approach to Quantum Field Theory, all suspicion is naturally abandoned. One knows in advance that this book can only lead to a genuine enrichment of the literature. DeWitt has made a formidable contribution to various areas of physics: general relativity, the interpretation of quantum mechanics, and most of all the quantization of non-Abelian gauge theories and quantum gravity. In addition, his pedagogical publications, especially the Les Houches schools of 1963 and 1983 [1, 2], have had a great impact on quantum field theory. All this makes the reader keen to pick up his new work and a deeper reading confirms the reviewer's initial enthusiasm. We must begin by alerting the potential readers of this book that it cannot be compared to any other book in the field (unless of course we are talking about references [1] and [2], of which the book under review is an extension and reworking). This uniqueness applies to both the scientific content and the way the ideas are presented. A quick description of this book and a brief explanation of its title should convince the reader of the book's unique quality. For DeWitt, a central concept of field theory is that of `space of histories'. For a field varphii defined on a given spacetime M, the set of all varphii(x) for all x in all charts of M defines its history. It is the space Phi of all possible histories (dynamically allowed or not) of the fields defined on M which is called the `space of histories' by DeWitt. If only

  1. Book Review:

    NASA Astrophysics Data System (ADS)

    McKane, Alan

    2003-12-01

    This is a book about the modelling of complex systems and, unlike many books on this subject, concentrates on the discussion of specific systems and gives practical methods for modelling and simulating them. This is not to say that the author does not devote space to the general philosophy and definition of complex systems and agent-based modelling, but the emphasis is definitely on the development of concrete methods for analysing them. This is, in my view, to be welcomed and I thoroughly recommend the book, especially to those with a theoretical physics background who will be very much at home with the language and techniques which are used. The author has developed a formalism for understanding complex systems which is based on the Langevin approach to the study of Brownian motion. This is a mesoscopic description; details of the interactions between the Brownian particle and the molecules of the surrounding fluid are replaced by a randomly fluctuating force. Thus all microscopic detail is replaced by a coarse-grained description which encapsulates the essence of the interactions at the finer level of description. In a similar way, the influences on Brownian agents in a multi-agent system are replaced by stochastic influences which sum up the effects of these interactions on a finer scale. Unlike Brownian particles, Brownian agents are not structureless particles, but instead have some internal states so that, for instance, they may react to changes in the environment or to the presence of other agents. Most of the book is concerned with developing the idea of Brownian agents using the techniques of statistical physics. This development parallels that for Brownian particles in physics, but the author then goes on to apply the technique to problems in biology, economics and the social sciences. This is a clear and well-written book which is a useful addition to the literature on complex systems. It will be interesting to see if the use of Brownian agents becomes

  2. Book Review:

    NASA Astrophysics Data System (ADS)

    Truscott, J. G.

    2004-05-01

    A book of this nature is long overdue; as could be expected from the pedigree of the editors, the coverage is comprehensive and, thanks to the authors selected, is of high quality. The book is divided into five sections, the central three of which are concerned with the measurement techniques themselves. The invasive techniques of mechanical testing and bone histology are dealt with in great detail at a level suitable for postgraduate students looking for an introduction to these techniques at a practical level. In the section dealing with the measurement techniques which use ionizing radiation, the chapters on DXA, neutron activation and radiogrammetry are well detailed and again at the appropriate level for postgraduate students. However, the chapters dealing with quantitative CT techniques are missing the sort of information that would have given them more authority. There is no mention of reconstruction algorithms or some of the typical shortcomings (e.g. partial volume artefacts) of these techniques and, given the excellent quality of the rest of the book, this was disappointing. The third of these technique sections deals with methods that do not use ionizing radiation. As one might expect with these two editors, the chapter on ultrasound is excellent and the coverage thorough and deep. The chapter on MRI and bone is particularly useful and timely as little has been published in this area and the debate about how best to measure bone quality in vivo has recently been rejoined. The chapters on finite element modelling and vibration analysis give a useful overview of the topics and have comprehensive reference lists for anyone who wishes to deepen their studies. The book has a useful introductory section. Bone biology is discussed in some detail, providing sufficient knowledge for the reader to be able to understand the basis and significance of the measurement techniques that follow. Exhaustive coverage is given to biological and radiation safety issues which

  3. Book Review:

    NASA Astrophysics Data System (ADS)

    Beenakker, C. W. J.

    2005-08-01

    Quantum Noise is advertised as a handbook, and this is indeed how it functions for me these days: it is a book that I keep within hand's reach, ready to be consulted on the proper use of quantum stochastic methods in the course of my research on quantum dots. I should point out that quantum optics, the target field for this book, is not my field by training. So I have much to learn, and find this handbook to be a reliable and helpful guide. Crispin Gardiner previously wrote the Handbook of Stochastic Methods (also published by Springer), which provides an overview of methods in classical statistical physics. Quantum Noise, written jointly with Peter Zoller, is the counterpart for quantum statistical physics, and indeed the two books rely on each other by frequent cross referencing. The fundamental problem addressed by Quantum Noise is how the quantum dynamics of an open system can be described statistically by treating the environment as a source of noise. This is a general problem in condensed matter physics (in particular in the context of Josephson junctions) and in quantum optics. The emphasis in this book in on the optical applications (for condensed matter applications one could consult Quantum Dissipative Systems by Ulrich Weiss, published by World Scientific). The optical applications centre around the interaction of light with atoms, where the atoms represent the open system and the light is the noisy environment. A complete description of the production and detection of non-classical states of radiation (such as squeezed states) can be obtained using one of the equivalent quantum stochastic formulations: the quantum Langevin equation for the field operators (in either the Ito or the Stratonovich form), the Master equation for the density matrix, or the stochastic Schrödinger equation for the wave functions. Each formulation is fully developed here (as one would expect from a handbook), with detailed instructions on how to go from one to the other. The

  4. Devonian and Mississippian rocks of the northern Antelope Range, Eureka County, Nevada

    USGS Publications Warehouse

    Hose, Richard Kenneth; Armstrong, A.K.; Harris, A.G.; Mamet, B.L.

    1982-01-01

    Lower through Upper Devonian rocks of the northern Antelope Range, Nev., consist of four formational rank units more than 800 m thick, separated from Mississippian units by an unconformity. The lower three Devonian units, the Beacon Peak Dolomite, McColley Canyon Formation, and Denay Limestone are known in other areas; the top unit, the Fenstermaker Wash Formation, is new. The Mississippian units, more than 280 m thick, are divisible into three units which are unlike coeval units elsewhere, and are herein named the Davis Spring Formation, Kinkead Spring Limestone, and Antelope Range Formation. Systematic sampling of the Devonian sequence has yielded relatively abundant conodonts containing several biostratigraphic ally significant taxa. The Mississippian units contain redeposited conodonts of chiefly Late Devonian and Early Mississippian (Kinderhookian) age together with indigenous Osagean foraminifers and algae in the Kinkead Spring Limestone.

  5. Book Design, Part I.

    ERIC Educational Resources Information Center

    Harms, Jeanne McClain; Lettow, Lucille

    1996-01-01

    Encourages teachers or school librarians to conduct a lesson in visual literacy by having children examine book design. Discusses book jackets and endpapers as book design elements, and highlights illustrations from five children's picture books. (PEN)

  6. Best Books 1982.

    ERIC Educational Resources Information Center

    School Library Journal, 1982

    1982-01-01

    This annotated bibliography lists 45 children's books and 29 young adult books selected by School Library Journal's Book Review staff and Young Adult Review committee, respectively. Arrangement is alphabetical by author with the grade level indicated for children's books. (EJS)

  7. X-ray computed tomography studies of gas storage and transport in Devonian shales

    SciTech Connect

    Lu, X.; Miao, P.; Watson, A.T. . Dept. of Chemical Engineering); Pepin, G.P.; Moss, R.M. ); Semmelbeck, M. )

    1994-07-01

    Devonian shales and other unconventional resources can be highly fractured and may have significant amounts of gas stored by adsorption. Conventional experiments are not well suited for characterizing the properties important for describing gas storage and transport in these media. Here, X-ray computed tomography scanning is used to determine gas storage in dynamic gas flow experiments on Devonian shale samples. Several important properties are obtained from these experiments, including fracture widths, adsorption isotherms, and matrix porosities and permeabilities.

  8. Book Review:

    NASA Astrophysics Data System (ADS)

    Vespignani, A.

    2004-09-01

    Networks have been recently recognized as playing a central role in understanding a wide range of systems spanning diverse scientific domains such as physics and biology, economics, computer science and information technology. Specific examples run from the structure of the Internet and the World Wide Web to the interconnections of finance agents and ecological food webs. These networked systems are generally made by many components whose microscopic interactions give rise to global structures characterized by emergent collective behaviour and complex topological properties. In this context the statistical physics approach finds a natural application since it attempts to explain the various large-scale statistical properties of networks in terms of local interactions governing the dynamical evolution of the constituent elements of the system. It is not by chance then that many of the seminal papers in the field have been published in the physics literature, and have nevertheless made a considerable impact on other disciplines. Indeed, a truly interdisciplinary approach is required in order to understand each specific system of interest, leading to a very interesting cross-fertilization between different scientific areas defining the emergence of a new research field sometimes called network science. The book of Dorogovtsev and Mendes is the first comprehensive monograph on this new scientific field. It provides a thorough presentation of the forefront research activities in the area of complex networks, with an extensive sampling of the disciplines involved and the kinds of problems that form the subject of inquiry. The book starts with a short introduction to graphs and network theory that introduces the tools and mathematical background needed for the rest of the book. The following part is devoted to an extensive presentation of the empirical analysis of real-world networks. While for obvious reasons of space the authors cannot analyse in every detail all the

  9. Book Review:

    NASA Astrophysics Data System (ADS)

    Arimondo, Ennio

    2004-07-01

    For many years the Institute of Physics has published books on hot topics based on a collection of reprints from different journals, including some remarks by the editors of each volume. The book on Optical Angular Momentum, edited by L Allen, S M Barnett and M J Padgett, is a recent addition to the series. It reproduces forty four papers originally published in different journals and in a few cases it provides direct access to works not easily accessible to a web navigator. The collection covers nearly a hundred years of progress in physics, starting from an historic 1909 paper by Poynting, and ending with a 2002 paper by Padgett, Barnett and coworkers on the measurement of the orbital angular momentum of a single photon. The field of optical angular momentum has expanded greatly, creating an interdisciplinary attraction for researchers operating in quantum optics, atomic physics, solid state physics, biophysics and quantum information theory. The development of laser optics, especially the control of single mode sources, has made possible the specific design of optical radiation modes with a high degree of control on the light angular momentum. The editors of this book are important figures in the field of angular momentum, having contributed to key progress in the area. L Allen published an historical paper in 1999, he and M J Padgett (together with M Babiker) produced few years ago a long review article which is today still the most complete basic introduction to the angular momentum of light, while S M Barnett has contributed several high quality papers to the progress of this area of physics. The editors' choice provides an excellent overview to all readers, with papers classified into eight different topics, covering the basic principles of the light and spin and orbital angular momentum, the laboratory tools for creating laser beams carrying orbital angular momentum, the optical forces and torques created by laser beams carrying angular momentum on

  10. Book Review:

    NASA Astrophysics Data System (ADS)

    Fabris, Júlio C.

    2004-04-01

    General relativity is one of the cornerstones of modern physics. In spite of this, the teaching of general relativity at undergraduate level remains quite marginal. The reasons for this particular situation are quite well known. We can quote, for example, two of them: general relativity requires specific mathematical tools that are somehow outside the mainstream of undergraduate technical development; moreover, this is a branch of physics whose observational and experimental applications have remained rare until recent times, and even though this scenario has changed dramatically in the last few years, the new situation has not yet been absorbed into undergraduate teaching. However, there are many textbooks devoted to the teaching of general relativity at undergraduate level. The recent book of J B Hartle, Gravity: An Introduction to Einstein's General Relativity, is a new proposal in this sense. It is perhaps one of the most interesting pedagogical approaches seeking to surmount the difficulties that arise when one tries to include general relativity in undergraduate teaching. In this new book, Hartle attempts to address the difficuties that must be faced by anyone who teaches general relativity at undergraduate level. In order to not scare the student with the hard technical preparation needed to obtain the basic equations of general relativity, Einstein's equations, he simply gives up the idea of introducing these equations at the very beginning. Instead, he chooses to present Einstein's equations, with most of the mathematics needed to do them, in the last part of the book. This delicate (and of course dangerous) choice has the advantage of introducing the reader first to the physical aspects of general relativity. This approach can be dangerous because the relevant solutions of the equations necessary to discuss the physical content of general relativiy are presented first without a formal derivation. But the author circumvents this potential drawback in a

  11. Book Review:

    NASA Astrophysics Data System (ADS)

    Straumann, N.

    2005-06-01

    This new book on quantum field theory by Michele Maggiore fits well into the Oxford Master Series in Physics, which is designed for final year undergraduate and beginning graduate students in physics. It is based on the teaching experience of the author with students in the fourth year at the University of Geneva. In this sense it is a two-semester course book for students exposed to quantum field theory for the first time. Maggiore gives, on slightly less than 300 pages, a balanced introduction to a vast field of twentieth century physics that will help students going on to study more advanced and specialized courses. Beside applications to many processes in particle physics that can also be found in many other textbooks, the author emphasizes conceptual, structural and methodological aspects of quantum field theory. After an introductory chapter, the group theoretical tools required to implement Lorentz invariance in quantum field theory are developed on 30 pages. Chapter 3 is devoted to classical field theory, emphasizing symmetries and conservation laws. The quantization of free fields in the next chapter follows traditional lines. Here one may miss a section describing the mathematical structure of the Fock space. It is also not said that in infinite dimensions von Neumann's uniqueness theorem for the representations of the canonical commutation relations no longer holds. The operations C, P, T are carefully discussed. In the relatively long chapter 5, perturbation theory and renormalization are developed. In this context the author discusses the modern view on renormalizability, and also emphasizes in a separate section the seriousness of the cosmological constant problem in quantum field theory. The next three chapters provide applications of the theory, especially to quantum electrodynamics and the low-energy limit of the electroweak theory. Chapters 9, 10, and 11 are meant as a bridge to more advanced courses. In these, path integral quantization, non

  12. Book Review:

    NASA Astrophysics Data System (ADS)

    Louko, J.

    2005-06-01

    Jean Zinn-Justin's textbook Path Integrals in Quantum Mechanics aims to familiarize the reader with the path integral as a calculational tool in quantum mechanics and field theory. The emphasis is on quantum statistical mechanics, starting with the partition function Tr exp(-β H) and proceeding through the diffusion equation to barrier penetration problems and their semiclassical limit. The 'real time' path integral is defined via analytic continuation and used for the path-integral representation of the nonrelativistic S-matrix and its perturbative expansion. Holomorphic and Grassmannian path integrals are introduced and applied to nonrelativistic quantum field theory. There is also a brief discussion of path integrals in phase space. The introduction includes a brief historical review of path integrals, supported by a bibliography with some 40 entries. As emphasized in the introduction, mathematical rigour is not a central issue in the book. This allows the text to present the calculational techniques in a very readable manner: much of the text consists of worked-out examples, such as the quartic anharmonic oscillator in the barrier penetration chapter. At the end of each chapter there are exercises, some of which are of elementary coursework type, but the majority are more in the style of extended examples. Most of the exercises indeed include the solution or a sketch thereof. The book assumes minimal previous knowledge of quantum mechanics, and some basic quantum mechanical notation is collected in an appendix. The material has a large overlap with selected chapters in the author's thousand-page textbook Quantum Field Theory and Critical Phenomena (2002 Oxford: Clarendon). The stand-alone scope of the present work has, however, allowed a more focussed organization of this material, especially in the chapters on, respectively, holomorphic and Grassmannian path integrals. In my view the book accomplishes its aim admirably and is eminently usable as a textbook

  13. Book Review:

    NASA Astrophysics Data System (ADS)

    Broderick, A.

    2006-10-01

    'The Black Hole at the Center of the Milky Way' collects and presents recent advances in galactic centre research in a unified form by some of the researches at the forefront of the field. This book presents an opportunity to review the observational evidence for the best constrained black hole candidate currently known. In my opinion, the authors succeed in producing a good topical reference, appropriate for advanced students and working researchers, providing and excellent summary of the state of near-infrared results in particular. While the title refers exclusively to the supermassive black hole associated with the compact radio source Sagittarius A*, the text has a broader focus, discussing the nuclear region of the galaxy. Indeed, this is necessary given that most of the restrictions upon the characteristics of the central supermassive black hole have been obtained indirectly via stellar observations in it's vicinity. This also has the virtue of introducing a number of interesting additional astrophysical mysteries associated with the galactic centre (e.g. the so-called 'paradox of youth', referring to the presence of excessively young stars). The first section of the book contains a primer on the astronomical techniques applied to the galactic Centre. As with the rest of the text, the discussion of near-infrared techniques dominates, providing only a short summary of radio interferometry, and optical through gamma-ray techniques. While this primer is a useful introduction for the working researcher, or advanced student, it is not exhaustive and thus presumes at least a passing familiarity with the methods discussed. The second and third sections are devoted to a summary of observations and their astrophysical interpretation, respectively. Necessarily there is considerable overlap between these and they may have benefited from being combined. Nevertheless, each subsection is relatively self-contained which, when combined with the numerous data and graphs

  14. Book Review:

    NASA Astrophysics Data System (ADS)

    Louko, Jorma

    2007-04-01

    Bastianelli and van Nieuwenhuizen's monograph `Path Integrals and Anomalies in Curved Space' collects in one volume the results of the authors' 15-year research programme on anomalies that arise in Feynman diagrams of quantum field theories on curved manifolds. The programme was spurred by the path-integral techniques introduced in Alvarez-Gaumé and Witten's renowned 1983 paper on gravitational anomalies which, together with the anomaly cancellation paper by Green and Schwarz, led to the string theory explosion of the 1980s. The authors have produced a tour de force, giving a comprehensive and pedagogical exposition of material that is central to current research. The first part of the book develops from scratch a formalism for defining and evaluating quantum mechanical path integrals in nonlinear sigma models, using time slicing regularization, mode regularization and dimensional regularization. The second part applies this formalism to quantum fields of spin 0, 1/2, 1 and 3/2 and to self-dual antisymmetric tensor fields. The book concludes with a discussion of gravitational anomalies in 10-dimensional supergravities, for both classical and exceptional gauge groups. The target audience is researchers and graduate students in curved spacetime quantum field theory and string theory, and the aims, style and pedagogical level have been chosen with this audience in mind. Path integrals are treated as calculational tools, and the notation and terminology are throughout tailored to calculational convenience, rather than to mathematical rigour. The style is closer to that of an exceedingly thorough and self-contained review article than to that of a textbook. As the authors mention, the first part of the book can be used as an introduction to path integrals in quantum mechanics, although in a classroom setting perhaps more likely as supplementary reading than a primary class text. Readers outside the core audience, including this reviewer, will gain from the book a

  15. Sedimentary history and biostratigraphy of Late Silurian-Early Devonian of southern Appalachians and southeastern Craton

    SciTech Connect

    Broadhead, T.W.; Capaccioli, D.A.; Neff, N.E.; Reid, S.R.

    1986-05-01

    The Late Silurian and Early Devonian sedimentary record of the southern Appalachians is preserved as a patchwork of shallow marine carbonate and terrigenous clastic rocks. These units commonly are bounded by unconformities, and biostratigraphic resolution has been lacking until recently. In Tennessee, the Sneedville formation (Hancock Dolomite of USGS usage) contains stromatoporoid faunas that correlate it with the Upper Silurian (Pridoli) Rondout (New York) and Tonoloway (central Appalachians) Formations, but recent conodont discoveries suggest a lower age limit in the Ludlow (crispa zone). Sneedville carbonates and clastics represent a broad range of shallow subtidal and peritidal facies that underwent periodic deepening and shoaling. In Georgia, correlative rocks are absent, and the Red Mountain Formation (Lower Silurian, Llandovery) is locally overlain by upper Lower Devonian Armuchee Chert-Frog Mountain Sandstone or by uppermost Devonian Chattanooga Shale. Reevaluation of the Red Mountain-Frog Mountain interval in Alabama showed a brachiopod fauna that correlated to the Keyser Limestone (uppermost Silurian-lowermost Devonian) of the central Appalachians. Cratonward, a relatively complete success of Upper Silurian-Lower Devonian carbonate rocks in west-central Tennessee (Decatur Limestone, Ross Formation) contrasts with the hiatus-bounded sections of the Appalachians. Toward the south, the Decatur intertongues with the lower Ross (eosteinhornensis zone), but to the north, the upper Decatur and Ross are both Devonian (woschmidti zone). The Decatur-Ross interval correlates with the Hunton Group of Oklahoma and is an ecologic analog and part temporal equivalent of parts of the Helderberg Group of New York.

  16. Practical aspects of Devonian shale exploration and development in Western West Virginia: One operator's experience

    SciTech Connect

    Murray, W.G.; Fairchild, M.; Heck, W.A.; Wolfe, R.T.; Woodfork, L.D.

    1984-05-01

    The discovery of new oil production (with associated gas) from the Devonian shales in western West Virginia in 1979 led to a tremendous increase in Devonian shale exploration and development in that area. The records of the West Virginia Geological and Economic Survey indicate that over 40% of drilling permits issued in 1982 were for various zones in the Devonian shales. With the decline in the gas market, the number of Devonian shale gas wells has declined in 1983. Nevertheless, activity in Ritchie, Pleasants, and Wood counties has remained very high. That activity is a source of considerable practical information on Devonian shale exploration and development. In fact, that play has provided an active testing ground for a variety of theories and techniques. The information presented in this paper is derived largely from the experience of one operator, Rendova Oil Company of Midland, Texas. That organization has been active in West Virginia since 1980 and, through the end of 1983, has drilled over 40 Devonian shale wells. That effort has been a continuous learning process in all phases of exploration and development. This paper attempts to share that experience by describing the methods and techniques that have been tried as well as Rendova's current practices. The discussion will include exploration rationale, drilling methods, and completion and production practices.

  17. Devonian sedimentation in the Xiqingshan Mountains: Implications for paleogeographic reconstructions of the SW Qinling Orogen

    NASA Astrophysics Data System (ADS)

    Yan, Zhen; Aitchison, Jonathan C.; Fu, Changlei; Guo, Xianqing; Xia, Wenjing; Niu, Manlan

    2016-08-01

    The Qinling Orogen between the North China and Yangtze plates comprises various accreted and collisional terranes, recording the evolution of the Proto-Tethyan Ocean and the formation of east Asia. Knowledge of the provenance and tectonic setting of a thick succession of E-W striking Devonian sedimentary rocks sandwiched tectonically between the Shangdan and Mianlue ophiolitic suture zones in this belt is essential to understanding the evolution of the Qinling Orogen and the assembly of the North China and Yangtze plates during the Late Paleozoic. Systematic studies of the Devonian sedimentary facies in the Xiqingshan Mountains indicate the northern margin of the South Qinling belt was uplifted prior to the Early Devonian. Lower Devonian sandstones are dominated by feldspathic litharenite (Q12-31F18-37L40-65), indicative of a continental arc derivation. Detrital zircon U-Pb data demonstrate that the Lower and Middle Devonian sandstones were derived respectively from ca. 770 Ma and ca. 400 Ma felsic arc-related magmatic sources. Devonian sedimentation in the Xiqingshan Mountains is interpreted to have occurred in a foreland basin between the Yangtze plate and the North Qinling continental arc.

  18. Book Repair Manual.

    ERIC Educational Resources Information Center

    Milevski, Robert J.

    1995-01-01

    This book repair manual developed for the Illinois Cooperative Conservation Program includes book structure and book problems, book repair procedures for 4 specific problems, a description of adhesive bindings, a glossary, an annotated list of 11 additional readings, book repair supplies and suppliers, and specifications for book repair kits. (LRW)

  19. Book Review:

    NASA Astrophysics Data System (ADS)

    Webb, Steve

    2008-11-01

    The Polish physicist Józio (Joseph, Josh, Jo) Rotblat was catapulted into the public eye when he (and the 'Pugwash Conferences' organization) received the 1995 Nobel Peace Prize. His life prior to that had been most distinguished but conducted well out of the public eye. Born and raised as a Jewish physicist in pre-World War II Poland, and thus potentially educationally disadvantaged, he battled away for education and scientific achievement. He came to Liverpool University just before the outbreak of World War II, worked in James Chadwick's laboratory on the early beginnings of neutron fission physics, moved to Los Alamos to take part in the US-UK collaborative Manhattan Project to build a nuclear bomb and was motivated by a desire to rid Poland of Nazi 'racial cleansing'. On realizing the US-UK goal was somewhat wider, he resigned this work and dedicated his life to the peaceful uses of radiation and the campaigns to rid the world of the potential world-eliminating possibility of nuclear war. For this purpose he interacted with Albert Einstein and Bertrand Russell, and in July 1957 founded the 'Pugwash Conferences', named for a small fishing village in Nova Scotia, Canada where the first was held. Along the way his personal life was no less dramatic. Cruel events conspired, and his wife Tola remained in Poland and was killed in the Nazi extermination camp at Majdanek. He grieved for his beloved Poland and those left behind or unaccounted for. He was suspected by some Americans of being a spy and had his personal papers and family artefacts impounded. After the war he was Professor of Medical Physics at St Bartholomew's Hospital, London for 30 years up to retirement. After John Roberts, he was the second editor of this journal Physics in Medicine and Biology from 1961-72 (see e.g. Bob Burns' paper in our 50th birthday issue, 2006. Kit Hill's little book which chronicles the life and times of Rotblat weaves together the key events in his personal and professional

  20. Book Review

    NASA Astrophysics Data System (ADS)

    Kragh, Helge

    2015-11-01

    Ever since the days of William Blake there has been an underground resistance against the soulless yet triumphant science and its unholy alliance with money, technology and political power. With the nearly undisputed hegemony that science and technological innovation has attained in the post-World War II era, this kind of resistance has resulted in numerous books and articles that in different ways warn against the dark sides of science and the socio-economic system that nourishes a science in degeneration. Classical examples include Herbert Marcuse's One-Dimensional Man (1964), Jacques Ellul's The Technological Society (1965), Theodore Roszak's The Making of a Counter Culture (1968), and Paul Feyerabend's Science in a Free Society (1978). A fair part of the literature written by sociologists and philosophers is not only critical to trends in modern science, but tends to or is overtly anti-science. The book under review belongs in some respects to this heterogeneous literary tradition, but Twilight of the Scientific Age is primarily directed against the institutional system of science and its associated ideology and not against science itself. Indeed, the author is himself a practicing scientist, an astrophysicist, and he emphasizes several times that he firmly believes in science, even that he loves it. He is not a "stupid cultural relativist," he asserts (p. 11), but a critical freethinker independent of dogmatic beliefs.

  1. Book Reviews

    NASA Astrophysics Data System (ADS)

    Catalano, Anthony

    1986-10-01

    Amorphous Silicon Solar Cells by K. Takahashi and M. Konagai is one of the first books dealing exclusively with the subject of amorphous silicon solar cells. The book was first published in Japanese in 1983 and was translated and published in English in 1986. Part 1, covering 94 pages, is a general introduction to solar energy, including the basic concepts, the prospects for cost reduction of the various competing photovoltaic technologies, and a discussion of several types of solar power systems, while Part 2 deals exclusively with the technical issues surrounding the application of amorphous silicon to solar cells. Throughout, reference is made to the impact of photovoltaics on the Japanese economy, both as a business activity and as a domestic supply of electrical energy. As the authors point out, photovoltaics is a national priority for the Japanese, with increasing business as well as government support. Although this was also once the case in the U.S., as memories of the recent energy crises fade, the bulk of this activity is shifting toward the Far East.

  2. Devonian climate change, breathing, and the origin of the tetrapod stem group.

    PubMed

    Clack, Jennifer A

    2007-10-01

    The diversification of the tetrapod stem group occurred during the late Middle through the Late Devonian, that is from the Givetian to Famennian stages about 385-365 million years ago. The relationships between the known taxa representing this radiation have currently reached a reasonable consensus so that interpretations of the order of appearance of tetrapod characters is possible. The immediate fish relatives of the earliest limbed tetrapods show what is interpreted as a progressive increase in the spiracular chamber and its opening to the outside. Here, this is inferred to be associated with an increased capacity for air-breathing. Lungs are thought to have been present in most early bony fishes, and were most likely ventilated by air-gulping. This could have brought about a facultative capacity for air-breathing, which the tetrapod stem group exploited to the greatest degree. These adaptations are shown not only in freshwater forms but also in estuarine and marginal marine forms. Estimates of oxygen levels during this period suggest that they were unprecedentedly low during the Givetian and Frasnian periods. At the same time, plant diversification was at its most rapid, changing the character of the landscape and contributing, via soils, soluble nutrients, and decaying plant matter, to anoxia in all water systems. The co-occurrence of these global events may explain the evolution of air-breathing adaptations in at least two lobe-finned groups, contributing directly to the rise of the tetrapod stem group. In contrast to recent studies, low atmospheric oxygen is not considered to be a causal factor in the lack of fossils documenting the evolution of Early Carboniferous tetrapods.

  3. Book Review:

    NASA Astrophysics Data System (ADS)

    Das, Ashok

    2007-01-01

    It is not usual for someone to write a book on someone else's Ph.D. thesis, but then Feynman was not a usual physicist. He was without doubt one of the most original physicists of the twentieth century, who has strongly influenced the developments in quantum field theory through his many ingenious contributions. Path integral approach to quantum theories is one such contribution which pervades almost all areas of physics. What is astonishing is that he developed this idea as a graduate student for his Ph.D. thesis which has been printed, for the first time, in the present book along with two other related articles. The early developments in quantum theory, by Heisenberg and Schrödinger, were based on the Hamiltonian formulation, where one starts with the Hamiltonian description of a classical system and then promotes the classical observables to noncommuting quantum operators. However, Dirac had already stressed in an article in 1932 (this article is also reproduced in the present book) that the Lagrangian is more fundamental than the Hamiltonian, at least from the point of view of relativistic invariance and he wondered how the Lagrangian may enter into the quantum description. He had developed this idea through his 'transformation matrix' theory and had even hinted on how the action of the classical theory may enter such a description. However, although the brief paper by Dirac contained the basic essential ideas, it did not fully develop the idea of a Lagrangian description in detail in the functional language. Feynman, on the other hand, was interested in the electromagnetic interactions of the electron from a completely different point of view rooted in a theory involving action-at-a-distance. His theory (along with John Wheeler) did not have a Hamiltonian description and, in order to quantize such a theory, he needed an alternative formulation of quantum mechanics. When the article by Dirac was brought to his attention, he immediately realized what he was

  4. Book Review:

    NASA Astrophysics Data System (ADS)

    Poisson, E.

    2006-09-01

    The motion of a charged particle interacting with its own electromagnetic field is an area of research that has a long history; this problem has never ceased to fascinate its investigators. On the one hand the theory ought to be straightforward to formulate: one has Maxwell's equations that tell the field how to behave (given the motion of the particle), and one has the Lorentz-force law that tells the particle how to move (given the field). On the other hand the theory is fundamentally ambiguous because of the field singularities that necessarily come with a point particle. While each separate sub-problem can easily be solved, to couple the field to the particle in a self-consistent treatment turns out to be tricky. I believe it is this dilemma (the theory is straightforward but tricky) that has been the main source of the endless fascination. For readers of Classical and Quantum Gravity, the fascination does not end there. For them it is also rooted in the fact that the electromagnetic self-force problem is deeply analogous to the gravitational self-force problem, which is of direct relevance to future gravitational wave observations. The motion of point particles in curved spacetime has been the topic of a recent Topical Review [1], and it was the focus of a recent Special Issue [2]. It is surprising to me that radiation reaction is a subject that continues to be poorly covered in the standard textbooks, including Jackson's bible [3]. Exceptions are Rohrlich's excellent text [4], which makes a very useful introduction to radiation reaction, and the Landau and Lifshitz classic [5], which contains what is probably the most perfect summary of the foundational ideas (presented in characteristic terseness). It is therefore with some trepidation that I received Herbert Spohn's book, which covers both the classical and quantum theories of a charged particle coupled to its own field (the presentation is limited to flat spacetime). Is this the text that graduate students

  5. Book Review:

    NASA Astrophysics Data System (ADS)

    Poisson, E.

    2005-10-01

    The ever growing relevance of general relativity to astrophysics and cosmology continues to motivate the publication of new textbooks which put the theory in a fresh perspective informed by recent developments. In the last few years we have witnessed the appearance of two new books which reflect this trend, and which stand proud among the classic relativity texts. While the 1970s were the decade of Weinberg [1] and Misner et al [2], and the 80s the decade of Schutz [3] and Wald [4], this is clearly the decade of Hartle [5] and Carroll. Hartle has introduced a novel pedagogical approach to teaching general relativity, which he convincingly argues [6] should be done in the standard undergraduate physics curriculum. His 'physics-first approach' emphasizes physical phenomena and minimizes mathematical formalism. Hartle achieves a lot by introducing only the spacetime metric and the geodesic equation, which are the main tools needed to explore curved spacetime and extract physical consequences. To be sure, to explain how the metric is obtained in the first place does require a background of differential geometry and the formulation of the Einstein field equations. But in Hartle's book this material is wisely presented at a later stage, after an ample sampling of the physics of curved spacetime has motivated the need for the advanced mathematics. Carroll follows instead the traditional route, what Hartle calls the 'math-first approach', in which one introduces first the required mathematical formalism and only then derives the physical consequences. He is, of course, in good company, as this is the method followed in all existing textbooks (with Hartle's being the sole exception). Carroll's approach may not be original, but it is tried and true, and the result of Carroll's efforts is an excellent introduction to general relativity. The book covers the standard topics that would be found in virtually all textbooks (differential geometry, the field equations, linearized

  6. Book Review:

    NASA Astrophysics Data System (ADS)

    Carlip, S.

    2006-10-01

    The early 1980s, when I first learned theory, were desperate times for graduate students. We searched frantically for coherent introductions, passing tattered copies of review articles around like samizdat, struggling over obscure references to ancient models of strong interactions, and flocking to lectures—not least those by Joe Polchinski—that promised to really explain what was going on. If only this book had been around, it would have saved much grief. Volume I, The Bosonic String, offers a clear and well organized introduction to bosonic string theory. Topics range from the 'classical' (spectra, vertex operators, consistency conditions, etc.) to the 'modern' (D-branes first appear in an exercise at the end of chapter 1, noncommutative geometry shows up in chapter 8). Polchinski does not hesitate to discuss sophisticated matters—path integral measures, BRST symmetries, etc.—but his approach is pedagogical, and his writing is lucid, if sometimes a bit terse. Chapters end with problems that are sometimes difficult but never impossible. A very useful annotated bibliography directs readers to resources for further study, and a nearly 30-page glossary provides short but clear definitions of key terms. There is much here that will appeal to relativists. Polchinski uses the covariant Polyakov path integral approach to quantization from early on; he clearly distinguishes Weyl invariance from conformal invariance; he is appropriately careful about using complex coordinates on topologically nontrivial manifolds; he keeps the string world sheet metric explicit at the start instead of immediately hiding it by a gauge choice. Volume II includes an elegant introduction to anticommuting coordinates and superconformal transformations. A few conventions may cause confusion—%, Polchinski's stress energy tensor, for instance, differs from the standard general relativistic definition by a factor of -2π, and while this is briefly mentioned in the text, it could easily be

  7. Book Review:

    NASA Astrophysics Data System (ADS)

    Borcherds, P.

    2005-03-01

    This book achieves what its subtitle indicates. The author skilfully weaves together the story of Bragg's life and of the scientific developments with which he was most closely involved. The author has a good understanding of Bragg's scientific work which he explains in considerable detail, with a number of diagrams reproduced from Bragg's papers, and manages to convey the excitement generated by Bragg's discoveries. The salient points of Bragg's life are well known. He was born and brought up in Australia and is still the youngest ever winner of a Nobel prize (though Josephson did his seminal work at a comparable age, it took many years for him to get his Prize). From 1914 to 1918 Bragg was involved with acoustic methods of detecting enemy guns. From 1919 to 1938 he was Professor of Physics in Manchester, and for about a year he was Director of the National Physical Laboratory. He then went to Cambridge as Cavendish Professor until 1953, when he moved to the Royal Institution (where his father had been). While an undergraduate at Cambridge 'Bragg's most influential teacher was...C T R Wilson [Nobel Laureate, 1927]...[whose] lectures "were the best, and delivery the worst, of any lectures to which I have ever been. He mumbled facing the board, he was very hesitant in his delivery, and yet the way he presented the subject was quite brilliant'' '. One wonders how long Wilson's inspirational teaching would survive today, with continual inspections and the requirement to satisfy the demands of the jobsworths. Bragg's comments on this would make interesting reading! Bragg was a very successful public lecturer on science. He made use of vivid analogies, many of which are quoted by Hunter. Since this book is published by Oxford University Press, I hope that some of them may appear in future editions of The Oxford Dictionary of Quotations. (Bragg is included in Mackay's A Dictionary of Scientific Quotations (Bristol: Institute of Physics Publishing)). There are too many

  8. Book Review:

    NASA Astrophysics Data System (ADS)

    Walcher, J.

    2006-10-01

    This book is a find. Mariño meets the challenge of filling in less than 200 pages the need for an accessible review of topological gauge / gravity duality. He is one of the pioneers of the subject and a clear expositor. It is no surprise that reading this book is a great pleasure. The existence of dualities between gauge theories and theories of gravity remains one of the most surprising recent discoveries in mathematical physics. While it is probably fair to say that we do not yet understand the full reach of such a relation, the impressive amount of evidence that has accumulated over the past years can be regarded as a substitute for a proof, and will certainly help to delineate the question of what is the most fundamental quantum mechanical theory. As has been the case in the past, it is in the context of Witten's 'topological' quantum theories that the mathematical framework is well enough established to firmly ground, and fully benefit from, the development of the physical theories. This book makes an important contribution to this new chapter in the math / physics interaction. There are two main instances of topological gauge/gravity duality. In the A-model, Chern Simons gauge theory on the 3-sphere is related to the closed topological string theory on the local Calabi Yau 3-fold {\\mathcal O}_{{\\mathbb P}^1}(-1) \\oplus{\\mathcal O}_{{\\mathbb P}^1} (-1), also known as the resolved conifold (Gopakumar-Vafa duality). In the B-model, certain types of matrix models are related on the gravity side to topological strings on certain cousins of the deformed conifold (Dijkgraaf-Vafa duality). In both cases, and similarly to the more physical AdS/CFT correspondence, the duality can be discovered by realizing the gauge theory as the target space theory of open strings ending on particular D-branes in a geometry closely related to the closed string background of the gravity theory. The A-branes supporting Chern Simons theory are wrapped on the Lagrangian three

  9. Book Review:

    NASA Astrophysics Data System (ADS)

    Kiefer, C.

    2005-10-01

    The most difficult unsolved problem in fundamental theoretical physics is the consistent implementation of the gravitational interaction into a quantum framework, which would lead to a theory of quantum gravity. Although a final answer is still pending, several promising attempts do exist. Despite the general title, this book is about one of them - loop quantum gravity. This approach proceeds from the idea that a direct quantization of Einstein's theory of general relativity is possible. In contrast to string theory, it presupposes that the unification of all interactions is not needed as a prerequisite for quantum gravity. Usually one divides theories of quantum general relativity into covariant and canonical approaches. Covariant theories employ four-dimensional concepts in its formulation, one example being the path integral approach. Canonical theories start from a classical Hamiltonian version of the theory in which spacetime is foliated into spacelike hypersurfaces. Loop quantum gravity is a variant of the canonical approach, the oldest being quantum geometrodynamics where the fundamental configuration variable is the three-metric. Loop quantum gravity has developed from a new choice of canonical variables introduced by Abhay Ashtekar in 1986, the new configuration variable being a connection defined on a three-manifold. Instead of the connection itself, the loop approach employs a non-local version in which the connection is integrated over closed loops. This is similar to the Wilson loops used in gauge theories. Carlo Rovelli is one of the pioneers of loop quantum gravity which he started to develop with Lee Smolin in two papers written in 1988 and 1990. In his book, he presents a comprehensive and competent overview of this approach and provides at the same time the necessary technical background in order to make the treatment self-contained. In fact, half of the book is devoted to 'preparations' giving a detailed account of Hamiltonian mechanics, quantum

  10. Exploration-production studies in newly drilled Devonian-Shale gas wells. Annual report, February 1, 1985-January 31, 1986

    SciTech Connect

    Graham, R.L.

    1986-02-01

    The Devonian shale has been recognized as an important source of gas in the Appalachian Basin. The program aids producers in the collection of reservoir data not normally collected and assists in the evaluation of the effectiveness of zone selection and stimulation designs and methods. The study should provide a fuller understanding of the relationships that affect productivity in the Devonian shale. The relationships between gas flows and geological features that control the production characteristics in the Devonian shale are being developed.

  11. The impact of precession and obliquity on the Late-Devonian greenhouse climate

    NASA Astrophysics Data System (ADS)

    De Vleeschouwer, D.; Crucifix, M.; Bounceur, N.; Claeys, P. F.

    2012-12-01

    To date, only few general circulation model (GCM) have been used to simulate the extremely warm greenhouse climate of the Late-Devonian (~370 Ma). As a consequence, the current knowledge on Devonian climate dynamics comes almost exclusively from geological proxy data. Given the fragmentary nature of these data sources, the understanding of the Devonian climate is rather limited. Nonetheless, the Late-Devonian is a key-period in the evolution of life on Earth: the continents were no longer bare but were invaded by land plants, the first forests appeared, soils were formed, fish evolved to amphibians and 70-80% of all animal species were wiped out during the Late Devonian extinction (~376 Ma). In order to better understand the functioning of the climate system during this highly important period in Earth's history, we applied the HadSM3 climate model to the Devonian period under different astronomical configurations. This approach provides insight into the response of Late-Devonian climate to astronomical forcing due to precession and obliquity. Moreover, the assessment of the sensitivity of the Late-Devonian climate to astronomical forcing, presented here, will allow cyclostratigraphers to make better and more detailed interpretations of recurring patterns often observed in Late-Devonian sections. We simulated Late-Devonian climates by prescribing palaeogeography, vegetation distribution and pCO2 concentration (2180 ppm). Different experiments were carried out under 31 different astronomical configurations: three levels for obliquity (ɛ = 22°; 23.5° and 24.5°) and eccentricity (e = 0; 0.03 and 0.07) were chosen. For precession, 8 levels were considered (longitude of the perihelion= 0°; 45°; 90°; 135°; 180°; 235°; 270°). First results suggest that the intensity of precipitation on the tropical Euramerican continent (also known as Laurussia) is highly dependent on changes in precession: During precession maxima (= maximal insolation in SH during winter

  12. Book Review:

    NASA Astrophysics Data System (ADS)

    Botet, R.

    2005-01-01

    This second edition of the popular book written by Quang Ho-Kim, Narenda Kumar and Chi Sing Lam, provides a comprehensive and interesting view of ten important topics in modern physics. All the sections have been updated: symmetry, lasers, superconductivity, chaos and fractals, stellar evolution, elementary particles and cosmology, while three new sections have been added to this edition: Bose-Einstein condensates, nanostructures and quantum computation. It is an impressive feat by the authors to cover such a wide panorama of physics from particles to cosmos and at a consistently high scientific level of information and explanation. This level is excellent and is at the frontier of current research but it does mean that some parts may be quite difficult for the undergraduate student. The ideal reader is probably the mature physicist revisiting familiar lines of thought, and following amazing bridges between distant topics. And if you are an active specialist in one particular topic, this book would give a clear insight on subjects outside your own field, allowing you to at last understand what your university colleague is really doing in a branch of physics with which you are totally unfamiliar. At the beginning, the style of writing can be disconcerting at this scientific level; equations are almost systematically avoided and illustrations are sparse, which can occasionally make the discussions rather ponderous, but the remarkable level of pedagogy and imaginative conception more than compensates for this. The fundamental ideas of exciting natural phenomena are elegantly discussed, while the authors never forget that physics is an experimental science, and address up-to-date applications in this manner. A brief bibliography is added at the end of each chapter, and a few simple exercises are given with answers. But the great strength of this book, and the main reason why it is worth reading by anyone interested in modern science, lies in the text itself which

  13. Pulmonary nuclear medicine: Techniques in diagnosis of lung disease

    SciTech Connect

    Atkins, H.L.

    1984-01-01

    This book presents papers on the application of nuclear medicine to the diagnosis of lung diseases. Topics considered include lung physiology and anatomy, radiopharmaceuticals in pulmonary medicine, pulmonary embolism, obstructive pulmonary disease, diffuse infiltrative lung disease, pneumoconioses, tumor localization scans in primary lung tumors, the interactions of heart diseases and lung diseases on radionuclide tests of lung anatomy and function, radionuclide imaging in pediatric lung diseases, and future possibilities in pulmonary nuclear medicine.

  14. Gas Research Institute Devonian (Ohio) gas shales workshop. Held in Charlestown, West Virginia; Marietta, Ohio and Pittsburgh, Pennsylvania on May 15, 16, and 17, 1991

    SciTech Connect

    1991-05-01

    The presentation slides from the May 1991 Gas Research Institute workshop on Devonian shales are assembled in this volume. They illustrate the following discussions: Devonian Gas Shales Workshop (Overview), Geologic Production Controls, Devonian Shale Formation Evaluation Based on Logs, Core Analysis, and Production Test Data, Fracture Identification and Orientation in the Devonian Shale, Stimulation Research Update and Insights from Recent Post-Fracture Diagnostics, Using a Layered Reservoir Model to Define Productive Layers and Model Well Performance in the Devonian Shales, New Well Testing Applications: Results and Applications of Devonian Shales Research, and GRI`s Field Research Program, 1991-1993.

  15. Book Review:

    NASA Astrophysics Data System (ADS)

    Ellis, G. F. R.

    2005-12-01

    Wolfgang Rindler is known as a writer of exceptional clarity. This quality is evident in this book as it explores in depth first special relativity, then general relativity, and finally relativistic cosmology. He bases his writing in the fundamental underlying ideas and principles that so successfully guided Einstein in his work, clarifying their nature and implications in an illuminating way with many examples. The usual suspects are there: the relativity principle and equivalence principle, the abolishing of absolute space, invariance of the speed of light, analytic and geometric representations of the Lorentz transformation, its kinematic and dynamic consequences, relativistic optics, Minkowski spacetime, energy and momentum conservation, and the Compton effect. Particularly useful is the emphasis on the unity of the whole: for example (p 63) that the kinematic effect of length shortening must imply a corresponding detailed mechanical explanation of that shortening. The tensor formulation of Maxwell's equations leads to the transformation properties of the electromagnetic field and consequent elegant derivation of the field of an infinite straight current; in this case, relativity is important even for slowly moving charges because an ordinary current moves a very big charge (p 151). General relativity is systematically introduced in stages, starting with curved spaces and moving on through static and stationary spacetimes, geodesics, and tensor calculus to the field equations. A considerable strength of the book is the careful detailed examination of the local and global geometry of the major significant solutions of the equations: the Schwarzschild spacetime and its Kruskal extension, plane gravitational waves, de sitter and anti-de Sitter spacetimes, and Robertson-Walker cosmologies. The latter includes a clear presentation of the dust and radiation model dynamics for the variety of possible cases, a detailed examination of observational relations, and

  16. Book Review:

    NASA Astrophysics Data System (ADS)

    Israel, W.

    2006-07-01

    The evaporation of a black hole formed by the collapse of matter is a nonunitary process involving loss of information. At least, this is how it appears in Hawking's semiclassical description, in which gravity is not quantized and the emergent radiation appears thermal. Since unitarity is one of the pillars of quantum mechanics there has been an understandable reluctance to accept this as an ironclad conclusion. Conformal field theories in flat space are manifestly unitary, and the AdS/CFT correspondence therefore suggests that the information trapped in the depths of the hole must find some way to escape—a conclusion almost universally accepted today, at least among particle theorists. Just how it could escape remains a mystery, however, since nothing can escape without violating causality until the black hole has shrunk too far to hold much information. Gerard 't Hooft and the senior author of this book, Leonard Susskind, have been vocal advocates of the view that the information paradox poses a real crisis for physics requiring significant paradigm shifts. They suggest that locality must be given up as an objective property of physical phenomena (even on large scales) and replaced by a new principle of 'black hole complementarity'. Specifically, there are two very different ways to view the process of collapse and evaporation. To a free-falling observer, nothing unusual happens at the horizon and matter and information fall deep into the hole. To a stationary observer hovering just outside the hole it appears instead that the matter and information are deposited on the horizon (which he experiences as very hot because of his large acceleration), to be eventually re-emitted from there as Hawking radiation. According to 't Hooft and Susskind, these must be viewed as equally valid, 'complementary' descriptions of the same process. Black hole complementarity is essentially the statement (supported by operational arguments) that their simultaneous validity cannot

  17. Book Review:

    NASA Astrophysics Data System (ADS)

    Coles, P.

    2006-02-01

    Cosmology is a discipline that encompasses many diverse aspects of physics and astronomy. This is part of its attraction, but also a reason why it is difficult for new researchers to acquire sufficient grounding to enable them to make significant contributions early in their careers. For this reason there are many cosmology textbooks aimed at the advanced undergraduate/beginning postgraduate level. Physical Foundations of Cosmology by Viatcheslav Mukhanov is a worthy new addition to this genre. Like most of its competitors it does not attempt to cover every single aspect of the subject but chooses a particular angle and tries to unify its treatment around that direction. Mukhanov has chosen to focus on the fundamental principles underlying modern cosmological research at the expense of some detail at the frontiers. The book places great emphasis on the particle-astrophysics interface and issues connected with the thermal history of the big-bang model. The treatment of big-bang nucleosynthesis is done in much more detail than in most texts at a similar level, for example. It also contains a very extended and insightful discussion of inflationary models. Mukhanov makes great use of approximate analytical arguments to develop physical intuition rather than concentrating on numerical approaches. The book is quite mathematical, but not in a pedantically formalistic way. There is much use of 'order-of-magnitude' dimensional arguments which undergraduate students often find difficult to get the hang of, but which they would do well to assimilate as early as possible in their research careers. The text is peppered with problems for the reader to solve, some straightforward and some exceedingly difficult. Solutions are not provided. The price to be paid for this foundational approach is that there is not much about observational cosmology in this book, and neither is there much about galaxy formation or large-scale structure. It also neglects some of the trendier recent

  18. Revisions to the original extent of the Devonian Shale-Middle and Upper Paleozoic Total Petroleum System

    USGS Publications Warehouse

    Enomoto, Catherine B.; Rouse, William A.; Trippi, Michael H.; Higley, Debra K.

    2016-04-11

    Technically recoverable undiscovered hydrocarbon resources in continuous accumulations are present in Upper Devonian and Lower Mississippian strata in the Appalachian Basin Petroleum Province. The province includes parts of New York, Pennsylvania, Ohio, Maryland, West Virginia, Virginia, Kentucky, Tennessee, Georgia, and Alabama. The Upper Devonian and Lower Mississippian strata are part of the previously defined Devonian Shale-Middle and Upper Paleozoic Total Petroleum System (TPS) that extends from New York to Tennessee. This publication presents a revision to the extent of the Devonian Shale-Middle and Upper Paleozoic TPS. The most significant modification to the maximum extent of the Devonian Shale-Middle and Upper Paleozoic TPS is to the south and southwest, adding areas in Tennessee, Georgia, Alabama, and Mississippi where Devonian strata, including potential petroleum source rocks, are present in the subsurface up to the outcrop. The Middle to Upper Devonian Chattanooga Shale extends from southeastern Kentucky to Alabama and eastern Mississippi. Production from Devonian shale has been established in the Appalachian fold and thrust belt of northeastern Alabama. Exploratory drilling has encountered Middle to Upper Devonian strata containing organic-rich shale in west-central Alabama. The areas added to the TPS are located in the Valley and Ridge, Interior Low Plateaus, and Appalachian Plateaus physiographic provinces, including the portion of the Appalachian fold and thrust belt buried beneath Cretaceous and younger sediments that were deposited on the U.S. Gulf Coastal Plain.

  19. Book Review:

    NASA Astrophysics Data System (ADS)

    Barbour, J. B.

    2007-02-01

    These colloquium proceedings will be valuable, the blurb says, for graduate students and researchers in cosmology and theoretical astrophysics. Specifically, the book 'looks at both the strengths and weaknesses of the current big bang model in explaining certain puzzling data' and gives a 'comprehensive coverage of the expanding field of cosmology'. The reality is rather different. Conference proceedings rarely compare in value with a solid monograph or good review articles, and Current Issues in Cosmology is no exception. The colloquium was convened by the two editors, who have both long harboured doubts about the big bang, and was held in Paris in June 2004. The proceedings contain 19 presented papers and relatively brief summary comments by four panel speakers. The questions and answers at the end of each talk and a general discussion at the end were recorded and transcribed but contain little of interest. The nature of the colloquium is indicated by panellist Francesco Bertola's comment: 'While in the 1950s it was possible to speak of rival theories in cosmology, now the big-bang picture has no strong rivals. This is confirmed by the fact that out of 1500 members of the IAU Division VIII (Galaxies and the Universe) only a dozen, although bright people, devote their time to the heterodox views.' This was largely a platform for them to give their views. At least half of the dozen, all the 'usual suspects', were present: Geoffery and Margaret Burbidge, Jayant Narlikar, Halton Arp, Chandra Wickramasinghe and, in spirit only but playing a role somewhat like the ghost of Hamlet's father, the late Fred Hoyle. Doubters presented 12 of the 19 papers. Orthodoxy should certainly be challenged and the sociology of science questioned, but I found two main problems with this book. The papers putting the orthodox view are too short, even perfunctory. The most that a serious graduate student would get out of them is a reference to a far better review article or book on modern

  20. Devonian Great Barrier Reef of Canning basin, Western Australia

    SciTech Connect

    Playford, P.E.

    1980-06-01

    A well-preserved Middle to Upper Devonian barrier-reef belt is exhumed as a series of limestone ranges for 350 km along the northern margin of the Canning basin. The reefs are of international importance for reef research because of the excellence of exposures and the lack of extensive dolomitization or structural deformation. They are also known in the subsurface, where they are regarded as prime objectives for oil exploration. The platforms were built by stromatoporoids, algae, and corals in the Givetian and Frasnian, and by algae in the Famennian. The platform and basin deposits were laid down nearly horizontally, whereas the marginal-slope deposits accumulated on steep depositional slopes. Geopetal fabrics, which quantify depositional and tectonic-compactional dip components, provide paleobathymetric data concerning the reef complexes and their fossil biotas. The reef limestones were subject to strong submarine cementation, resulting in very early porosity destruction, whereas the back-reef deposits of the platform interiors remained largely uncemented and retained most of their primary porosity. Stylolitization and associated compaction were greatest in limestones whose primary porosity was not destroyed by early submarine cementation. Consequently the platform interiors have compacted more than the margins, resulting in the typical concave shape of many platforms. Cementation concomitant with stylolitization destroyed most of the porosity that remained in the limestones after early submarine diagenesis. The most porous rocks now are dolomites having secondary moldic porosity. 27 figures.

  1. Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus

    NASA Astrophysics Data System (ADS)

    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.

  2. Patch reef modeling: a comparison of Devonian and recent examples

    SciTech Connect

    Precht, W.F.

    1983-09-01

    In reef research, models have been developed to define variations in the lithic and biotic development of facies. Walker and Alberstadt, and Hoffman and Narkiewicz developed models for growth of ancient reef communities. Although these models form a solid foundation by which patch reefs can be classed and zoned, they are neither complete nor accurate for all reef types. A comparison was made of Lower Devonian patch reefs from the Appalachian basin of New York, New Jersey, and Pennsylvania, and Holocene examples from the Bahamas and Florida Keys to identify the structure, orientation, community variability, and succession of the reef biofacies. The complexion and genesis of the carbonate lithofacies were also studied. Results show similarities; these include the size, areal distribution, 3-D geometry, wave-resistance potential, lateral sequences of facies, sedimentary textures and structures, vertical zonation explained by growth from low-energy to high-energy regimes, biotic diversity, growth habit and form, and postmortem alteration. Thus, when used in conjunction with the traditional models, the recent can serve as the basis for a general model which include most patch reef types. However, these models should not be used as explicit analogs for all Phanerozoic reefs. Knowing and understanding the limitations of these comparative studies are essential to a fuller comprehension of the potential for variations which exist within and between the traditional models.

  3. Facies analysis of a Devonian carbonate shoreline system (northern Italy)

    NASA Astrophysics Data System (ADS)

    Galli, Gianni

    1986-01-01

    The upper part of a back-reef carbonate, regressive sequence of the Cima Ombladet (Devonian, Carnic Alps, Italy) has been investigated. According to textures, sedimentary structures, faunal content and bedding types, it has been subdivided into eight main facies, which represent three main environments deposited within a high-energy shoreline system: (1) a shoreface (open lagoon, brachiopod bar and intramicrudite facies); (2) a lower foreshore (pond, ridge, bioclast shoal and intraclast shoal facies); and (3) an upper foreshore consisting of well-sorted sands with cryptalgal laminae. Three main shallowing-upward sequences have been recognised within the complicated facies mosaic, which is a peculiar feature of the sequence: (1) a shoreface bar sequence formed within the open lagoon and was longshore and tidal current-dominated; (2) a storm bar sequence; and (3) a beach sequence formed within the foreshore. Storms, other than normal shoreline processes, played a significant role in controlling sand accumulation and geometry in the foreshore. In particular the beach was built by a stepwise lateral assemblage of sand bodies of different composition and originated from the reworking of open lagoonal bars and of the lagoonward terminations of the reef-flat environments, occurring as linear ridges.

  4. Organic content of Devonian shale in western Appalachian basin.

    USGS Publications Warehouse

    Schmoker, J.W.

    1980-01-01

    In the organic-rich facies of the Devonian shale in the western part of the Appalachian basin, the distribution of organic matter provides an indirect measure of both gas in place and the capacity of the shale to supply gas to permeable pathways.The boundary between organic-rich ('black') and organic-poor ('gray') facies is defined here as 2% organic content by volume. The thickness of organic-rich facies ranges from 200ft in central Kentucky to 1000ft along the Kentucky-West Virginia border. The average content of the organic-rich facies increases from 5% by volume on the edge to 16% in central Kentucky. The net thickness of organic matter in the organic-rich facies shows the amount of organic material in the shale, and is the most fundamental of the organic-content characterizations. Net thickness of organic matter ranges between 20 and 80ft (6.1 and 24.4m) within the mapped area.-from Author

  5. Shallow seismic investigations of Devonian-shale gas production

    SciTech Connect

    Williams, R.T.; Ruotsala, J.E.; Kudla, J.J.; Dunne, W.E.

    1982-06-01

    The foremost conclusion of this study is that fractured Devonian shale gas reservoirs, as exemplified by the Cottageville field, are detectable by seismic reflection methods. Further, the target is not particularly difficult, once the nature of the seismic anomaly is understood. The preferred exploration rationale is based on travel time anomalies related to lowered acoustic velocity within the gas-bearing zone. In the simplest case the travel time anomaly causes an apparent down-warp or sag in a flat-lying reflector. This conclusion is developed in Parts B and C of this report. Concerning the high-resolution extension of the seismic method, which is the subject of Part A, there are essentially two separate conclusions which can be drawn. One is that additional, valuable subsurface information can be obtained by recording seismic data at frequenies higher than those in common use by the petroleum industry at the time of this writing. The other is that it is feasible to obtain seismic reflection data on a smaller scale, using less costly instrumentation, than is typically employed in the petroleum industry. However, it is not yet possible to say whether such small scale surveying will be practical from an industry point of view.

  6. Earth's oldest 'Bobbit worm' - gigantism in a Devonian eunicidan polychaete.

    PubMed

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

    2017-02-21

    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.

  7. History of gas production from Devonian shale in eastern Kentucky

    SciTech Connect

    Kemper, J.R.; Frankie, W.T.; Smath, R.A.; Moody, J.R.; Johnston, I.M.; Elkin, R.R.

    1988-08-01

    More than 10,500 wells that penetrate the Devonian shale have been compiled into a data base covering a 25-county area of eastern Kentucky. This area includes the Big Sandy gas field, the largest in the Appalachian basin, and marginal areas to the southwest, west, and northwest. The development of the Big Sandy gas field began in the 1920s in western Floyd County, Kentucky, and moved concentrically outward through 1970. Since 1971, the trend has been for infill and marginal drilling, and fewer companies have been involved. The resulting outline of the Big Sandy gas field covers most of Letcher, Knott, Floyd, Martin, and Pike Counties in Kentucky; it also extends into West Virginia. Outside the Big Sandy gas field, exploration for gas has been inconsistent, with a much higher ratio of dry holes. The results of this study, which was partially supported by the Gas Research Institute (GRI), indicate that certain geologic factors, such as fracture size and spacing, probably determine the distribution of commercial gas reserves as well as the outline of the Big Sandy gas field. Future Big Sandy infill and extension drilling will need to be based on an understanding of these factors.

  8. Late Devonian conodonts and event stratigraphy in northwestern Algerian Sahara

    NASA Astrophysics Data System (ADS)

    Mahboubi, Abdessamed; Gatovsky, Yury

    2015-01-01

    Conodonts recovered from the Late Devonian South Marhouma section comprise 5 genera with 31 species (3 undetermined). The fauna establishes the presence of MN Zones 5, undifferentiated 6/7, 8/10 for the Middle Frasnian, the MN Zones 11, 12, 13 for the Upper Frasnian as well as the Early through Late triangularis Zones in the basal Famennian. The outcropping lithological succession is one of mostly nodular calcilutites alternating with numerous marly and shaly deposits, which, in the lower and upper part, comprise several dysoxic dark shale intervals. Among these the Upper Kellwasser horizon can be precisely dated and as such the presence of the terminal Frasnian Kellwasser Event is recognized for the first time in Algeria. Both the Middlesex and Rhinestreet Events cannot yet be precisely located, but supposedly occur among the dark shale horizons in the lower part of the section. However, their assignment to a precise level has so far not been established. Though poor in conodont abundance the South Marhouma section provides first evidence of the presence of several Montagne Noire conodont zones within the so far widely unstudied Frasnian of the Ougarta Chain. As such it is considered representative for the northwestern Algerian Saoura region.

  9. Bacterial mediation, red matrices diagenesis, Devonian, Montagne Noire (southern France)

    NASA Astrophysics Data System (ADS)

    Préat, Alain; Mamet, Bernard; Bernard, Alain; Gillan, David

    1999-07-01

    Two Devonian red carbonate rock sections are studied in the Montagne Noire, at Coumiac (Frasnian/Famennian) and at the Pic de Vissou (Eifelian/Givetian). The sediments are grey-red mudstones and wackestones rich in pelagic fossils. They are characteristic of an outer ramp. The Coumiac sequence is condensed with numerous hardgrounds and hiatuses. The Pic de Vissou succession is more complete and of shallower origin. In both cases, the origin of the red coloration of the micritic matrix is probably linked to bacterial activity which produced submicronic hematite. Both iron and manganese concentrations are low (average 0.2%). Bacteria form ferruginous microstromatolites, blisters, microtufts, `hedgehogs' filling sponge perforations and thin continuous mineralized films (probably biofilms). Hardgrounds are underlined by ferruginous microstromatolites. The origin of the matrix color is probably related to the destruction of these bacterial constructions, the submicronic hematite ultimately coating the crystal faces of the calcite mosaic. During early lithification, microfissures appeared and were invaded by microbial colonies. Scanning electron microscopy (SEM) shows that these colonies are composed of spheroidal beads. This suggests continuity of the bacterial activity during early diagenesis. Later on, these early fissures were cut by burrows. Subsequently a secondary fissure network transected all the previously mentioned sedimentary structures. This late fissure network is characterized by diagenetically remobilized hematite and/or calcite. The latest alterations are stylolites and ultimate tectonic fractures.

  10. Devonian landscape heterogeneity recorded by a giant fungus

    NASA Astrophysics Data System (ADS)

    Boyce, C. Kevin; Hotton, Carol L.; Fogel, Marilyn L.; Cody, George D.; Hazen, Robert M.; Knoll, Andrew H.; Hueber, Francis M.

    2007-05-01

    The enigmatic Paleozoic fossil Prototaxites Dawson 1859 consists of tree-like trunks as long as 8 m constructed of interwoven tubes <50 mm in diameter. Prototaxites specimens from five localities differ from contemporaneous vascular plants by exhibiting a carbon isotopic range, within and between localities, of as much as 13‰ δ13C. Pyrolysis gas chromatography mass spectrometry highlights compositional differences between Prototaxites and co-occurring plant fossils and supports interpretation of isotopic distinctions as biological rather than diagenetic in origin. Such a large isotopic range is difficult to reconcile with an autotrophic metabolism, suggesting instead that, consistent with anatomy-based interpretation as a fungus, Prototaxites was a heterotroph that lived on isotopically heterogeneous substrates. Light isotopic values of Prototaxites approximate those of vascular plants from the same localities; in contrast, heavy extremes seen in the Lower Devonian appear to reflect consumption of primary producers with carbon-concentrating mechanisms, such as cryptobiotic soil crusts, or possibly bryophytes. Prototaxites biogeochemistry thus suggests that a biologically heterogeneous mosaic of primary producers characterized land surfaces well into the vascular plant era.

  11. Dolomitization of the Devonian Jefferson Formation, south-central Montana

    SciTech Connect

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

    1989-07-01

    Dolomitization of the Devonian Jefferson Formation in south-central Montana probably occurred as a result of multiple dolomitizing events. Petrographic and geochemical studies show the presence of five distinct dolomite types: cathodoluminescently nonzoned euhedral dolomite, nonzoned subhedral/anhedral dolomite mosaics, zoned euhedral dolomite, irregularly luminescent dolomite, and zoned dolomite cement. Data from Jefferson Formation dolomite indicate a progression from early, nonstoichiometric, euhedral replacive dolomites, to nearly stoichiometric, subhedral/anhedral dolomite mosaics. {delta}{sup 18}O and {delta}{sup 13}C ratios decrease with increasing degree of dolomitization. Euhedral replacive dolomites in lower dolomitic limestone layers probably formed by early, refluxing hypersaline brines in evaporitic settings. These dolomites are the least stoichiometric and have the heaviest {delta}{sup 18}O signatures of all dolomites which were analyzed. Massive dolomitization of the upper two-thirds of the Jefferson Formation probably occurred when dolomitizing brines migrated downward through the upper Jefferson Formation during deposition of thick evaporite sequences in the overlying Three Forks Formation. Mass balance calculations indicate that this mechanism was more than adequate to cause the massive dolomitization in the upper Jefferson Formation. Massive dolomitization during Logan Gulch deposition may have been the final phase of dolomitization, or dolomite may have recrystallized to more stoichiometric, {sup 18}O- and {sup 13}C-depleted subhedral/anhedral mosaics during later burial.

  12. Invasive Species and Biodiversity Crises: Testing the Link in the Late Devonian

    PubMed Central

    Stigall, Alycia L.

    2010-01-01

    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

  13. The implication of the oxygen isotopic composition of lower Devonian micritic limestone, Oklahoma

    SciTech Connect

    Gao, G. . Dept. of Geological Sciences)

    1992-01-01

    The documented [delta]O-18 values of presumably well preserved lower Devonian marine carbonates are significantly lower than those of post-Devonian carbonates. These have been interpreted to have resulted from either O-18-depleted or hot oceans, relative to post-Devonian oceans. To test these hypotheses, micritic limestones were sampled for oxygen (as well carbon and strontium) isotope analysis from the lower Devonian (Lochkovian) Haragan-Bois d'Arc formations of the Hunton Group, South-Central Oklahoma. Of the 25 analyzed samples, 22 samples are characterized by high [delta]C-13 values and ranging from [minus]1.9[per thousand] to [minus]2.9[per thousand](PDB). These are the highest [delta]C-13 limestones were deposited in a shallow normal marine setting and have both [delta]C-13 values and Sr-87/Sr-86 ratios similar to other lower Devonian carbonates elsewhere, the high [delta]O-18 values of these limestones are unlikely to have originated either from any unusual depositional setting or from diagenetic alteration at low temperatures by O-18- and Sr-87-enriched basinal brines. The high [delta]O-18 values of the Haragan-Bois d'Arc limestones are thus interpreted to represent near-primary signals. The temperatures and [delta]O-18 values of early Devonian seawater can be constrained to have been 25 [+-] 7 C and 0 [+-] 1[per thousand] (SMOW), respectively. This implies that neither O-18 depletion nor high temperatures characterized early Devonian oceans.

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

    PubMed

    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

  15. Book Review:

    NASA Astrophysics Data System (ADS)

    Unruh, W. G.

    2006-02-01

    Quantum mechanics is one of the most successful theoretical structures in all of science. Developed between 1925-26 to explain the optical spectrum of atoms, the theory over the succeeding 80 years has been extended, first to quantum field theories, gauge field theories, and now even string theory. It is used every day by thousands of physicists to calculate physical phenomena to exquisite precision, with no ambiguity in the results. To claim that this is a theory which is not understood by those physicists is absurd. And yet, as eminent a physicist as Richard Feynman, who did as much as anyone else to extend quantum theory to field theories and was a master at producing those exquisite calculations, could say that anyone who claimed they understood quantum theory clearly did not understand quantum theory. One hundred years ago Einstein postulated one of the most unsettling features of the theory, the wave-particle duality, with his particulate explanation for light of the photoelectric effect, and an explanation which was in direct conflict with Maxwell's brilliant development of a wave, or field, theory of light. Einstein believed that the particulate nature would ultimately be explainable by some sort of non-linear theory of electromagnetism, and was outraged by the acceptance of the community of the probabilistic quantum theory. His programme was of course dealt a (near?) fatal blow by Bell's discovery that the three desiderata - a theory which agrees with experiment, a theory which is local in its effects, and a theory in which nature, at its heart, is not probabilistic - are incompatible. That discomfort felt by Einstein and by Feynman is felt by numerous other people as well. This discomfort is heightened by the fact that the theory of gravity, another of Einstein's great achievements, has resisted all efforts at reconciliation with quantum mechanics. This book explores that discomfort, and tries to pin down what the locus of that discomfort is. For many

  16. Book Review:

    NASA Astrophysics Data System (ADS)

    Trimble, Virginia

    2007-05-01

    Here are two textbooks, both published by Springer and each roughly half devoted to cosmology—the large scale structure and evolution of the Universe. I can imagine a context (not the same context) in which each would be useful. And there the similarities largely end. Bergstrom and Goobar's (hereafter B&G) other topic is particle astrophysics, and they are addressing students who already have some knowledge of advanced quantum mechanics and classical field theory (or who can master some relativistic dynamics and the Dirac equation on the basis of a couple of very information-dense appendices). The book is meant for use at the graduate level, probably the second year by US standards (the authors are from Stockholm). Schneider (hereafter PS), on the other hand, begins with galaxies, and then alternates between cosmological topics of gradually increasing sophistication (expanding universe to CMB fluctuations) and additional galactic topics—clusters, quasars and all. The book is meant as the second half of an introductory astronomy/astrophysics course for physics majors, and in the US would fit into an upper division `capstone' course. Each is meant for a single semester class at the target level, and might be squeezed into a 10-week term with elimination of some topics. B&G is a paperback of a second edition, with colour confined to a central block of plates, relatively few graphs and drawings, but lots of complex equations. PS is a hard cover translation from a German original, with colour used freely in astronomical images and graphs throughout, with fewer and less complex equations. Though the nominal difference in copyright date is only two years (2006 for PS, 2004 for B&G), the former is considerably more up to date, mentioning, for instance, that the third year WMAP results are not different enough from the first year to justify redoing drawings and such (I agree). What can you expect to get if you buy one or both of these? B&G have a homepage of error

  17. Best Books of 1977

    ERIC Educational Resources Information Center

    Gerhardt, Lillian N.; And Others

    1977-01-01

    School Library Journal book review editors have selected and annotated their choices for the best children's and young adults' books from those books that were submitted for review during 1977 by general book trade book publishers. Included in the annotations are: author, title, publisher, price, and recommended reading and interest levels. (JPF)

  18. Book Review:

    NASA Astrophysics Data System (ADS)

    Peacock, John

    2007-04-01

    ), but the latter is surprising in the context of a subject whose whole purpose is to observe the properties of primordial perturbations that may have arisen from inflation. Instead, the text concentrates on the technical heartland of the transport theory for CMB photons, and the Newtonian and relativistic theory for the development of CMB anisotropies, including polarization. It closes with more observationally-based chapters on general statistical aspects of the CMB sky, a digest of the recent results from WMAP, and an outlook. These are welcome, but the book really stands or falls on its treatment of the core physics of anisotropies. Without going too much into specifics, it can be fairly stated that the treatment given of the main material on CMB fluctuations is geared more to working professionals than to students. There is a good deal of useful technical detail, but it is not always derived systematically, and sometimes arises by reference to the research literature. There are no problem sets or worked examples, and not much attempt at intuitive illumination. As an example, one might point to the large-angle anisotropies of the CMB, which were first analysed in the classic Sachs Wolfe paper of 1967. The relativistic transport equation is there, but one looks in vain for the separation into the Sachs Wolfe effect proper (potential perturbations at last scattering) and the integrated effect of evolution since then. This latter ISW effect is in fact of huge interest in current research, since it is one of the methods for probing whether the vacuum energy differs from a cosmological constant. In general, the text seems strangely patchy on issues of contemporary interest, certainly in terms of its emphasis. It is as if the three authors contributed material separately without achieving a full integration. On the more positive side, the book has the advantage that it presents a Russian view of the subject. So much of the initial work on the `Relic Radiation' (a much

  19. Book Review:

    NASA Astrophysics Data System (ADS)

    Stewart, J. M.

    2006-02-01

    In 1952, Mme Yvonne Choquet-Bruhat published a major paper, Théorème d'existence pour certains systèmes d'équations aux dérivées partielles non linéaires (Acta Math. 88 141-225), which laid the foundation for modern studies of the Cauchy problem in general relativity. The fiftieth anniversary of this event was celebrated with an eponymous Cargèse Summer School in 2002. The proceedings of that summer school are summarized electronically (as audio, video, transparencies and lecture notes, where available) on a DVD archive included with this volume, and are also available on the internet. However the organizers decided that a separate volume describing the 'state of the art in mathematical general relativity' would be useful, and this book is the result. It includes some material not covered in the school and excludes some school material which has been covered adequately elsewhere. Unfortunately, I was unable to find, electronically, a table of contents, which every prospective purchaser would wish to see, and so this review does in fact list all the articles, ordered, roughly, by length. About one fifth of the book is devoted to a survey of Smoothness at Null Infinity and the Structure of Initial Data by Helmut Friedrich. This is a modern study of gravitational radiation, and the analysis of Einstein's equations. It is extremely helpful to survey all of this material, including some of the latest developments, using a consistent notation. This article is strongly recommended to anyone hoping to gain a foothold in this area. Note also that 47 pages of transparencies have become 84 book pages. Lars Andersson has surveyed, in The Global Existence Problem in General Relativity, some results and conjectures about the global properties of 3+1-dimensional spacetimes with a compact Cauchy surface. Again it is very useful to have essentially all of the known results presented in a consistent notation. This material is not on the DVD. Yvonne Choquet-Bruhat has

  20. Book Review:

    NASA Astrophysics Data System (ADS)

    Rogister, A. L.

    2004-03-01

    John Wesson’s well known book, now re-edited for the third time, provides an excellent introduction to fusion oriented plasma physics in tokamaks. The author’s task was a very challenging one, for a confined plasma is a complex system characterised by a variety of dimensionless parameters and its properties change qualitatively when certain threshold values are reached in this multi-parameter space. As a consequence, theoretical description is required at different levels, which are complementary: particle orbits, kinetic and fluid descriptions, but also intuitive and empirical approaches. Theory must be carried out on many fronts: equilibrium, instabilities, heating, transport etc. Since the properties of the confined plasma depend on the boundary conditions, the physics of plasmas along open magnetic field lines and plasma surface interaction processes must also be accounted for. Those subjects (and others) are discussed in depth in chapters 2 9. Chapter 1 mostly deals with ignition requirements and the tokamak concept, while chapter 14 provides a list of useful relations: differential operators, collision times, characteristic lengths and frequencies, expressions for the neoclassical resistivity and heat conduction, the bootstrap current etc. The presentation is sufficiently broad and thorough that specialists within tokamak research can either pick useful and up-to-date information or find an authoritative introduction into other areas of the subject. It is also clear and concise so that it should provide an attractive and accurate initiation for those wishing to enter the field and for outsiders who would like to understand the concepts and be informed about the goals and challenges on the horizon. Validation of theoretical models requires adequately resolved experimental data for the various equilibrium profiles (clearly a challenge in the vicinity of transport barriers) and the fluctuations to which instabilities give rise. Chapter 10 is therefore

  1. Book Review:

    NASA Astrophysics Data System (ADS)

    Wainwright, John

    2007-04-01

    The present volume is an introduction to general relativity and cosmology, at a level suitable for beginning graduate students or advanced undergraduates. The book consists of two main parts, the first entitled `Elements of differential geometry', and the second `The theory of gravitation'. Chapters 2-7, part I, introduce the basic ideas of differential geometry in a general setting, and are based on previously unpublished notes by one of the authors. On the one hand, the treatment is modern in that it uses a `top-down' approach, i.e. starting with general differentiable manifolds, and deferring the introduction of a metric tensor until after the notions of affine connection and curvature have been introduced. On the other hand, the treatment is classical in that it relies heavily, though not exclusively, on index notation. The general material, chapters 1-7, is then followed by four more specialized chapters dealing with matters of specific interest for general relativity. Topics include symmetry groups acting on Riemannian manifolds, with spherically symmetric spacetimes and spatially homogeneous spacetimes as examples, the efficient calculation of curvature, and the Petrov classification of the Weyl curvature tensor using spinors. Part II deals with general relativity and cosmology. The basic assumptions of the theory and its application to spherically symmetric gravitational fields are discussed in two chapters, and there is some historical material and motivation for the basic assumptions at the beginning of the book. The final chapter contains a detailed discussion of the Kerr solution. But the main emphasis in part II is on relativistic cosmology, in particular the analysis of cosmological models more general than the familiar Friedmann-Lemaitre (FL) models. The material on cosmology begins with a discussion of relativistic hydrodynamics and thermodynamics. The kinematical quantities (rate of expansion, shear, etc, of a timelike congruence) are introduced

  2. Linking Fossil Fish Cyclicity and Paleoenvironmental Proxies in the mid-Devonian

    NASA Astrophysics Data System (ADS)

    Grogan, D.; Whiteside, J. H.; Trewin, N. H.; Johnson, J. E.

    2009-12-01

    The significant radiation of fishes throughout the Devonian, combined with the abundance of well-preserved fossil fish assemblages from this period, provides for a high-resolution record of prevalent fish taxa in the Orcadian basin of North Scotland. In addition to their ability to serve as a lake-level and lake-chemistry proxy, the waxing and waning of dominant fish taxa exhibit a pronounced cyclicity, suggesting they respond to broader climate rhythms. Recent studies of mid-Devonian lacustrine sedimentary sequences have quantitatively demonstrated the presence of Milankovitch cyclicity in geochemical and gamma ray proxy records. Spectral analysis of gamma ray data show a strong obliquity peak usually associated with ice-house conditions; this obliquity signal is unexpected as tropical latitudes in the mid-Devonian are traditionally thought to have been in a greenhouse climate. Geochemical data include the measurement of bulk carbon and nitrogen stable isotopes, molecule-specific carbon isotopes of plant biomarkers, and depth ranks from eight sections of the Caithness Flagstone Group of the Orcadian Basin. Evidence for orbital forcing of climate change paired with the fossil fish record provides a unique opportunity to establish an astronomically calibrated timescale for the mid-Devonian, as well as to make a quantitative assessment of the validity of a greenhouse climate existing in the mid-Devonian.

  3. Clinical and experimental pathology of lung cancer

    SciTech Connect

    McVie, J.G.; Bakker, W.; Wagenaar, S.C.; Carney, D.

    1986-01-01

    This book contains 17 selections. Some of the titles are: Flow cytometric DNA analysis in the study of small cell carcinoma of the lung; Mechanisms of oncogenesis; Adhesion mechanisms in liver metastasis; Current concepts in the therapy of small cell lung cancer; Application of monoclonal antibodies in imaging and therapy; and Clinical applications of the biologic properties of small cell lung cancer.

  4. Views on Science Books.

    ERIC Educational Resources Information Center

    Stubbs, Harry C.

    1979-01-01

    Reviews six new children's science books. Five of the reviewed books deal separately with the topics of the space shuttle project, cosmology and stellar evolution, space, forest fires, and the electromagnetic spectrum; one is a book of geography puzzles. (GT)

  5. The Comic Book Project

    ERIC Educational Resources Information Center

    Lopate, Phillip

    1976-01-01

    Describes the work and preparation--as well as the student response-- that went into the Comic Book Club in an elementary school which resulted in a student developed comic book and comic book fair. (HOD)

  6. Views on Science Books.

    ERIC Educational Resources Information Center

    Stubbs, Harry C.

    1979-01-01

    Reviews six new children's science books. Five of the reviewed books deal separately with the topics of the space shuttle project, cosmology and stellar evolution, space, forest fires, and the electromagnetic spectrum; one is a book of geography puzzles. (GT)

  7. Book Review:

    NASA Astrophysics Data System (ADS)

    Altschul, Brett D.

    2007-06-01

    All the physics we observe in our world is underlain by special relativity, a theory that has survived for more than a hundred years, in many respects completely intact. Yet despite its status as the most stringently tested theory in all of physics, special relativity is still frequently questioned. In the last decade and a half, many scientists have come to believe that special relativity, as Einstein formulated it, will need to be modified to accommodate a quantum theory of gravity. {\\it Special Relativity: Will it Survive the Next 101 Years?} is a volume intended to introduce the reader to this new and still slightly controversial area of research. The book is divided into four parts. The first part is essentially historical. It consists of an essay discussing Einstein's work in the context of contemporary technological developments and a amusing note by R W P Drever on a precision Lorentz test that he performed literally in his backyard. These set the stage for the more modern material that follows. Part II discusses the theory of relativity and its mathematical foundations, from completely modern perspectives. There is much here that may be new even for experts on special relativity, and a significant level of mathematical sophistication on the part of the reader is assumed. A number of the lectures delve into the crucial question of how special relativity and its generalizations can be combined with quantum mechanics. The third part discusses theoretical models of Lorentz violation, and all the important paradigms that appear in the current literature are considered. These include the standard model extension (an effective field theory), modified dispersion relations and 'double special relativity', and noncommutative geometry. These lectures generally delve into less detail than those in part II; the focus is on helping the reader digest the new principles that must arise in theories without Lorentz symmetry. The final part of the volume covers current

  8. Book Review:

    NASA Astrophysics Data System (ADS)

    Borcherds, P. H.

    2004-09-01

    There is a new tradition in England called Apple Day which is held on some day in October. The actual day varies from place to place. For instance, in 2003, 23 October was Apple Day at Woolsthorpe Manor, the house where Isaac Newton was born and where, during the Plague, he is said to have developed the theory of gravity. (For information on future Apple Days see, for example, http://www.nationaltrust.org.uk/main/thingstodo.) Last year in our garden we picked an apple which weighed one pound, thirteen and a half ounces (1 lb 13 1/2 oz or 29 1/2 oz). The following day we went to an Apple Day event where there were many exotic apples on display, varieties which are not sold in shops. One of the varieties there was called 'Twenty Ounce'. By now you may be wondering what all this has to do with the book being reviewed. We shall return to this later. This entertaining book is ostensibly about units, in particular about Imperial and metric units, but there are numerous informative digressions. The author reminds us that almost every country 'with the exception of the United States, North and South Yemen, Burma and Brunei' has gone metric. He points out that the United States (US) became officially metric in 1893. However, as early as 1866, the US legal definition of the metre was 39.370000 inches. He tells us that after World War II the (US) inch was rounded down (from 25.400051) to 25.4 mm. There is no mention that the Imperial (British) inch was simultaneously rounded up from 25.399956 mm to 25.4 mm. The author frequently digresses, covering such matters as the trisection of angles and Eratosthenes' graphic solution for duplicating the cube. There is an informative discussion on the length of the day: appropriately 25 December, which lasts for 24 h and 30 s, is the longest day. He shows how with cycles and epicycles one can construct an ellipse. Ptolemy did not realize the importance of the focus of the ellipse. The author discusses various topics in the development of

  9. Book Review:

    NASA Astrophysics Data System (ADS)

    Giannetto, E.

    2005-08-01

    This book is a sort of tribute to Rob Clifton (1964 2002), Associate Professor of Philosophy and Associate Director of the Center for Philosophy of Science at the University of Pittsburgh, philosopher of physics and editor of the journal Studies in the History and Philosophy of Modern Physics, who tragically died of cancer. It contains fourteen papers by Clifton, for the most part written in collaboration with other authors (Jeffrey Bub (2), Sheldon Goldstein, Michael Dickson, Hans Halvorson (6), Adrian Kent (2)), published between 1995 and 2002. The choice of papers made by the editors is very impressive. They concern the foundations of quantum mechanics and quantum field theory. Among the issues discussed are the modal interpretations of quantum mechanics, the problems of hidden variables theories, non-locality, Bell's inequality, the Einstein Podolsky Rosen paradox, Lorentz invariance, de-coherence, non-contextuality, complementarity, entanglement and quantum information. A consequence of such investigations is that non-separability is a more complex issue than violation of Bell's inequality. Apart from the perspective one can follow—whether one agrees or not with Clifton—these papers are effective contributions to an understanding of the problems involved in the foundations of quantum mechanics. The most interesting parts, in my opinion, are related to the extension of the discussion of foundational problems to quantum field theory: on the algebraic approach, and on the twin concepts of particle and vacuum. Non-locality appears to be `worse' in relativistic quantum field theory than in non-relativistic quantum mechanics. All the papers deal with relevant epistemological and even historical aspects of quantum mechanics interpretations, but all the issues are discussed from a technical, logical and mathematical approach. A complete bibliography of Clifton's papers is given at the end of the volume.

  10. Book Review:

    NASA Astrophysics Data System (ADS)

    Parthasarathy, R.

    2005-06-01

    This book gives a clear exposition of quantum field theory at the graduate level and the contents could be covered in a two semester course or, with some effort, in a one semester course. The book is well organized, and subtle issues are clearly explained. The margin notes are very useful, and the problems given at the end of each chapter are relevant and help the student gain an insight into the subject. The solutions to these problems are given in chapter 12. Care is taken to keep the numerical factors and notation very clear. Chapter 1 gives a clear overview and typical scales in high energy physics. Chapter 2 presents an excellent account of the Lorentz group and its representation. The decomposition of Lorentz tensors under SO(3) and the subsequent spinorial representations are introduced with clarity. After giving the field representation for scalar, Weyl, Dirac, Majorana and vector fields, the Poincaré group is introduced. Representations of 1-particle states using m2 and the Pauli Lubanski vector, although standard, are treated lucidly. Classical field theory is introduced in chapter 3 and a careful treatment of the Noether theorem and the energy momentum tensor are given. After covering real and complex scalar fields, the author impressively introduces the Dirac spinor via the Weyl spinor; Abelian gauge theory is also introduced. Chapter 4 contains the essentials of free field quantization of real and complex scalar fields, Dirac fields and massless Weyl fields. After a brief discussion of the CPT theorem, the quantization of electromagnetic field is carried out both in radiation gauge and Lorentz gauge. The presentation of the Gupta Bleuler method is particularly impressive; the margin notes on pages 85, 100 and 101 invaluable. Chapter 5 considers the essentials of perturbation theory. The derivation of the LSZ reduction formula for scalar field theory is clearly expressed. Feynman rules are obtained for the λphi4 theory in detail and those of QED

  11. Controls on reservoir development in Devonian Chert: Permian Basin, Texas

    SciTech Connect

    Ruppel, S.C.; Hovorka, S.D.

    1995-12-01

    Chert reservoirs of the Lower Devonian Thirtyone Formation contain a significant portion of the hydrocarbon resource in the Permian basin. More than 700 million bbl of oil have been produced from these rocks, and an equivalent amount of mobile oil remains. Effective exploitation of this sizable remaining resource, however, demands a comprehensive appreciation of the complex factors that have contributed to reservoir development. Analysis of Thirtyone Formation chert deposits in Three Bar field and elsewhere in the Permian basin indicates that reservoirs display substantial heterogeneity resulting from depositional, diagenetic, and structural processes. Large-scale reservoir geometries and finer scale, intra-reservoir heterogeneity are primarily attributable to original depositional processes. Despite facies variations, porosity development in these cherts is principally a result of variations in rates and products of early silica diagenesis. Because this diagenesis was in part a function of depositional facies architecture, porosity development follows original depositional patterns. In reservoirs such as Three Bar field, where the Thirtyone Formation has been unroofed by Pennsylvanian deformation, meteoric diagenesis has created additional heterogeneity by causing dissolution of chert and carbonate, especially in areas of higher density fracturing and faulting and along truncated reservoir margins. Structural deformation also has exerted direct controls on heterogeneity that are particularly noteworthy in reservoirs under waterflood. High-density fracture zones create preferred flow paths that result in nonuniform sweep through the reservoir. Faulting locally creates compartments by offsetting reservoir flow units. As such, the processes and models defined here improve understanding of the causes of heterogeneity in all Thirtyone chert reservoirs in the Permian basin and aid recovery of the sizable hydrocarbon resource remaining in these rocks.

  12. Evaluation of EL836 explosive stimulation of Devonian gas shale

    SciTech Connect

    Barbour, T G

    1980-07-01

    This report presents an evaluation of EL836, an explosive developed at E.I. duPont de Nemours and Company Laboratories, in stimulating gas shale. EL836 is a water gel type explosive with a high aluminum content. The computational evaluation of EL836 involved four one-dimensional cyclindrical geometry calculations to assess the influence of two equation-of-state descriptios of EL836, the effect or rock yielding and the effect of internal crack pressurization. Results of a computational evaluation of the EL836 explosive in stimulating Devonian gas shale suggest the following: Extensive plastic yielding will occur in a region immediate to the borehole. Extensive tensile fracture will occur in a region that begins at the outer boundary of plastic deformation and terminates at more than 100 borehole radii. Without a mechanism of ;near-wellbore fracture, such as crushing or pre-cracking during drilling or intentional borehole grooving, the plastic flow that occurs adjacent to the wellbore causes stress redistributions which prohibit early-time (less than a millisecond) tensile fracture immediate to the wellbore and thus prohibits gas penetration from the wellbore into the crack system. The barrier that the near-wellbore plastic zone presents to gas flow from the wellbore is reduced in radial dimension as time increases. Natural fractures in the wellbore wall or cataclysmic deformation and fracture adjacent to the wellbore, as a result of the explosive detonation, will likely assist in breaking down the barrier to gas flow. Very significatn enhancement is achieved in the EL836 stimulation treatment when gases penetrate the stress-wave induced radial cracks. Only minor differences were observed in the EL836 stimulation effects when comparison is made between two different explosive equations-of-state. 33 figures, 2 tables.

  13. Bulge Migration and Pinnacle Reef Development, Devonian Appalachian Foreland Basin.

    PubMed

    Ver Straeten CA; Brett

    2000-05-01

    Detailed stratigraphic analyses of Late Emsian and Early Eifelian (Lower to Middle Devonian) carbonate-dominated strata in the northern Appalachian Basin indicate anomalous, locally varying relative sea level changes and inversions of topography. The distribution of a major basal-bounding unconformity, basinal pinnacle reefs, local absence of parasequences, and eastward migration of shallow marine carbonate lithofacies and related biofacies in the Onondaga Limestone and underlying strata mark the retrograde migration of an elongate, northeast-southwest-trending area of positive relief, bordered on its cratonward side by a similarly migrating basin of intermediate depth. These features are thought to represent the forebulge and back-bulge basin of the Appalachian foreland basin system as it developed during a time of relative quiescence within the Acadian Orogeny. However, the relatively small size of the bulgelike feature (ca. 80-100-km-wide, 20-50-m positive relief), its great distance from the probable deformation front (>400 km), and the lack of a well-developed foredeep immediately adjacent to the bulgelike feature may indicate that it represents a smaller-scale flexural high ("flexural welt") superposed over the cratonward edge of the larger-scale classical forebulge of the basin. Development of shallow-water reefs on the crest of the bulge during sea level lowstand, followed by migration of the bulge and widespread transgression, permitted growth of economically significant pinnacle reefs in the deep basin center. Further subsurface reef exploration should concentrate along the projected position of the bulge during the basal Onondaga lowstand.

  14. Cyclic platform dolomites of Devonian Jefferson Formation, Montana and Idaho

    SciTech Connect

    Dorobek, S.L.

    1986-05-01

    Preliminary field study indicates that the Devonian Jefferson Formation in southwestern Montana and adjacent parts of Idaho consists of cyclic sequences of shallow marine platformal dolomites that grade basinward into slope sediments deposited on a steepened carbonate ramp. Individual shallowing-upward, platformal cycles are 25 to < 1 m (82 to 3 ft) thick and, from top to bottom, consist of: solution-collapse breccia caps; cryptalgal dolomudstone; rare ooid dolograinstone; thin-bedded Amphipora dolowackestone; sucrosic dolostones with abundant lenticular to domal stromatoporoids; thin-bedded, fine-grained, shaly dolostones with closely spaced hardgrounds that grade upward into burrow-homogenized, irregularly bedded dolostones. Thinner cycles (< 5 m or 16 ft thick) contain fewer basal lithologies and typically consist only of cryptalgal dolomudstone with breccia caps. The 1 to 25-m thick cycles comprise larger scale sequences (30-60 m or 100-200 ft thick), in which smaller scale cycles become progressively thinner toward the top of large-scale sequences. These shallowing-upward carbonate cycles probably formed in response to glacio-eustatic sea level fluctuations. Current estimates for the time span represented by the Jefferson formation (9 m.y.), divided by the number of shallowing-upward cycles, indicate that each cycle represents an average time span of 0.6 to 1.0 m.y.. This time span suggests that either: (1) average sedimentation rates were unrealistically slow during deposition of each cycle (< 0.1-3 cm/1000 years); (2) breccia caps represent long periods of subaerial exposure (> 0.5 to about 0.2 m.y.); or (3) the Jefferson Formation was deposited during a much shorter time span than previously thought.

  15. Was the Earth's Magnetic Field Weak in the Late Devonian?

    NASA Astrophysics Data System (ADS)

    Anwar, T.; Biggin, A. J.; Kravchinsky, V. A.; Pavlov, V.

    2014-12-01

    Very few data exist to describe geomagnetic field behaviour in the Late Devonian (LD). Samples, which have recently been Ar-Ar dated to 364-377 Myr ago, of LD-aged volcanics and instrusives from the Viluy large igneous province in Siberia are investigated. These units have already demonstrated reliable, palaeomagnetic directions consistent with the retention of a primary remanence. Microwave Thellier-type palaeointensity experiments (mostly IZZI protocol with partial thermoremanent magnetization checks) were performed on 55 samples from 16 sites, of which, 12 samples from 4 sites provide satisfactory paleointensity data. Arai plots are strongly concave-up in shape but multiple lines of evidence support that this is caused by a strong component of magnetisation overprinting a weak primary magnetisation rather than by lab-induced alteration or multidomain behaviour. The samples display corresponding distinct directional components, positive pTRM checks and little or no zig-zagging of the Arai plot. Furthermore, the results of non-heating pseudo-Thellier experiments support the existence of a strong component overprinting a much weaker one. The site-mean paleointensities, ranging from 5.3-11.1 μT and which correspond to a virtual axial dipole moments (VADMs) of (1.0-2.1) ×1022 Am2, indicate that the LD was a time of extremely weak magnetic field intensity. It provides the evidence that the superchron state, between ~310 and 265 Myr ago, is preceded by very weak field in the LD (~60 Myr before the superchron). If low dipole moment can be considered an indicator of high reversal frequency (as appears to be the case in the mid-Jurassic) then our results support that rapid transitions between reversal hyperactivity and superchron states are a recurring feature in the palaeomagnetic record, potentially linked to simultaneous episodes of true polar wander.

  16. Writing a book review.

    PubMed

    Peh, W C; Ng, K H

    2010-09-01

    A book review is a form of academic writing that provides a succinct yet critical analysis evaluating the content, style, merit and significance of a book. The reader should gain insight into the strengths and weaknesses of the book, aided by input from the reviewer. The four stages of writing a book review are: introducing the book, outlining its contents, highlighting parts of the book by selecting particular chapters or themes, and giving a detailed evaluation.

  17. Book Review:

    NASA Astrophysics Data System (ADS)

    Fulling, S. A.

    2006-05-01

    saying that gravity was not only an honourable member of the forces of nature, but ultimately the source of them all. It has become a cliche that the unification of relativity with quantum theory is the central problem of contemporary physics. In the 1950s, before strings, non-Abelian monopoles, or even quasars, Bryce DeWitt was applying the quantum-field-theoretical methods and conceptual framework of his mentor, Julian Schwinger, to gravity. His central insight was that the conceptual and technical problems of quantum gravity were closely analogous to those of gauge theories. He developed a unified, relentlessly abstract, and highly personal vision of the fundamentals of physical theory. It was, and is, expressed in idiosyncratic and condensed notation often different from the languages of mainstream field theorists, traditional relativists, and mathematicians alike. In short, he has never been easy reading. His ideas were systematically presented in famous lecture series at the Les Houches summer schools on Relativity, Groups and Topology in 1963 [1] and 1983 [2], the book Supermanifolds [3], and a number of (relatively) shorter expositions that have been widely read. By the middle 1970s the methods that he had developed mainly for gravity were widely recognized as very useful for Yang Mills gauge theories, and his work had become part of the mainstream. Now, another 20 years after the second Les Houches, we have this final testament of Bryce DeWitt's ideas. At over 1000 pages in two volumes in a fabric-covered slipcase, it is the sort of work usually described as 'magisterial' (meaning, perhaps, 'no one has yet succeeded in reading it all the way through'). Over the years, of course, DeWitt learned many new things and thought of ways to say the old things better. Accordingly, the new books consist of reworkings of the most important parts of the older writings together with some new material. Oxford University Press is to be thanked and congratulated for the care it

  18. Devonian Novaculites as source of oil in Marathon-Ouachita thrust system

    SciTech Connect

    Zemmels, I.; Grizzle, P.L.; Walters, C.C.; Haney, F.R.

    1985-02-01

    The Arkansas Novaculite of southern Oklahoma and the Caballos Novaculite of west Texas (both Devonian) form fractured reservoirs in the Marathon-Ouachita thrust system. These formations were examined to ascertain their petroleum potential. Findings include the following. (1) The thermal maturity of the thrust system conforms to the maturity of the sequence that it has overthrust, suggesting that this allochthonous facies is not anomalously mature. (2) Shale units within the novaculites contain oil-prone organic matter in sufficient concentrations to constitute source rocks. (3) The composition of oils from Isom Springs field in southern Oklahoma and from McKay Creek field in west Texas is virtually identical and generally resembles Devonian oils in Oklahoma and west Texas. The authors concluded that the Devonian novaculites of the Marathon-Ouachita thrust system are self sourcing and do not require a fortuitous juxtaposition of source rocks of a different age to produce a commercial deposit.

  19. Characterizing the role of desorption in gas production from Devonian shales

    SciTech Connect

    Lane, H.S.; Watson, A.T. ); Lancaster, D.E. )

    1991-01-01

    Previous investigators suggest that more than one half of the gas stored in the Devonian Shales may exist in an adsorbed state. However, adsorption is considered to be an unconventional mode of gas storage and is not often accounted for in conventional reservoir engineering analysis. This article examines the role that desorption may play in gas production from Devonian Shale reservoirs. The results suggest that accounting from gas desorption can have a significant effect on production forecasts and estimates of gas reserves. A methodology is presented for detecting the presence of gas desorption and for estimating the parameters that describe the desorption process from Devonian Shale production data. The accuracy of these parameter estimates and the effects of stimulating the desorption mechanisms are also examined.

  20. Application of a new multiple fracturing technique to enhance gas production in Devonian shale

    SciTech Connect

    Cuderman, J.F.

    1984-01-01

    A new multiple fracturing technology has been applied in stimulating a Devonian shale gas well. In this new technique, propellants are used to obtain controlled pressurization of the wellbore to produce multiple fractures. The pressurization is controlled by suitable choice of propellants having different burn rates. The pressure risetime is the most important parameter governing fracture behavior. Methods are presented for specifying both the risetime and propellants to achieve it for Devonian shales. The Devonian shale stimulation was conducted in a 1040 m deep well in Meigs Co., Ohio. The experimental installation and hardware used are described together with results which include an increase in production from 190 m/sup 3//day to 623 m/sup 3//day. 7 references, 5 figures, 1 table.

  1. New data on Upper Devonian stratigraphy of the northwestern Kuznetsk basin: Evidence from foraminifera and chondrichthyes

    NASA Astrophysics Data System (ADS)

    Timokhina, I. G.; Rodina, O. A.

    2015-09-01

    The thorough investigation of four Frasnian-Famennian (Upper Devonian) boundary sections along the right side of the Tom River northwest of Kemerovo yielded new data on the composition of their foraminiferal and ichthyofaunal assemblages. These data were used for development of the zonal foraminiferal scale for Upper Devonian deposits of the northwestern Kuznetsk coal basin and the first zonal scale for their subdivision on the basis of Elasmobranchii remains and for correlation of the examined sections between each other and with Upper Devonian sequences in other regions. The analysis of foraminiferal and ichthyofaunal assemblages, which are the most widespread in upper Frasnian sections of the northwestern Kuznetsk coal basin, made it possible to specify the regional stratigraphic model.

  2. Earliest known coelacanth skull extends the range of anatomically modern coelacanths to the Early Devonian.

    PubMed

    Zhu, Min; Yu, Xiaobo; Lu, Jing; Qiao, Tuo; Zhao, Wenjin; Jia, Liantao

    2012-04-10

    Coelacanths are known for their evolutionary conservatism, and the body plan seen in Latimeria can be traced to late Middle Devonian Diplocercides, Holopterygius and presumably Euporosteus. However, the group's early history is unclear because of an incomplete fossil record. Until now, the only Early Devonian coelacanth is an isolated dentary (Eoactinistia) from Australia, whose position within the coelacanths is unknown. Here we report the earliest known coelacanth skull (Euporosteus yunnanensis sp. nov.) from the Early Devonian (late Pragian) of Yunnan, China. Resolved by maximum parsimony, maximum likelihood and Bayesian analyses as crownward of Diplocercides or as its sister taxon, the new form extends the chronological range of anatomically modern coelacanths by about 17 Myr. The finding lends support to the possibility that Eoactinistia is also an anatomically modern coelacanth, and provides a more refined reference point for studying the rapid early diversification and subsequent evolutionary conservatism of the coelacanths.

  3. The north-subducting Rheic Ocean during the Devonian: consequences for the Rhenohercynian ore sites

    NASA Astrophysics Data System (ADS)

    von Raumer, Jürgen F.; Nesbor, Heinz-Dieter; Stampfli, Gérard M.

    2016-11-01

    Base metal mining in the Rhenohercynian Zone has a long history. Middle-Upper Devonian to Lower Carboniferous sediment-hosted massive sulfide deposits (SHMS), volcanic-hosted massive sulfide deposits (VHMS) and Lahn-Dill-type iron, and base metal ores occur at several sites in the Rhenohercynian Zone that stretches from the South Portuguese Zone, through the Lizard area, the Rhenish Massif and the Harz Mountain to the Moravo-Silesian Zone of SW Bohemia. During Devonian to Early Carboniferous times, the Rhenohercynian Zone is seen as an evolving rift system developed on subsiding shelf areas of the Old Red continent. A reappraisal of the geotectonic setting of these ore deposits is proposed. The Middle-Upper Devonian to Early Carboniferous time period was characterized by detrital sedimentation, continental intraplate and subduction-related volcanism. The large shelf of the Devonian Old Red continent was the place of thermal subsidence with contemporaneous mobilization of rising thermal fluids along activated Early Devonian growth faults. Hydrothermal brines equilibrated with the basement and overlying Middle-Upper Devonian detrital deposits forming the SHMS deposits in the southern part of the Pyrite Belt, in the Rhenish Massif and in the Harz areas. Volcanic-hosted massive sulfide deposits (VHMS) formed in the more eastern localities of the Rhenohercynian domain. In contrast, since the Tournaisian period of ore formation, dominant pull-apart triggered magmatic emplacement of acidic rocks, and their metasomatic replacement in the apical zones of felsic domes and sediments in the northern part of the Iberian Pyrite belt, thus changing the general conditions of ore precipitation. This two-step evolution is thought to be controlled by syn- to post-tectonic phases in the Variscan framework, specifically by the transition of geotectonic setting dominated by crustal extension to a one characterized by the subduction of the supposed northern slab of the Rheic Ocean

  4. Lignification and mycorrhization in Devonian-Carboniferous times. Studies on French material.

    NASA Astrophysics Data System (ADS)

    Strullu-Derrien, C.; Gerrienne, P.; Strullu, D. G.

    2009-04-01

    One of the most important events in the history of Life is the colonisation of the land by plants; the earliest steps occurred about 460 million years ago. A few million years later, during the Devonian period, plants became more and more abundant. Tracheophytes evolved from small dichotomous axes with terminal sporangia to plants reaching 40 m in height. The evolution of large erect plants with tree-habit was achieved by the Pseudosporochnales (Monilophytes) during the Middle Devonian and the Archaeopteridales (Lignophytes) at the end of the Devonian. We describe here a possible early representative of the Lignophytes from the Lower Devonian from the Chateaupanne quarry (Anjou, Armorican massif, France). Pyritized axes show well-preserved anatomy. The primary xylem is centrarch or mesarch and is circular in transverse section. It is surrounded by a zone of radially aligned cells that is interpreted as a simple secondary xylem. Both primary and secondary (?) xylems comprise P-type tracheids. The link with symbiotic fungi goes back to the dawn of the land plants. The evidence of paramycorrhizae occurring in the prostrate axes of Aglaophyton major from the Rhynie Chert dated to the early Devonian. Aglaophyton however did not possess tracheids that characterize the tracheophytes. By Late Devonian and Carboniferous times, various rooting structures had evolved in tracheophytes. Our reinvestigation of historical thin sections from silicified material from the Late Pennsylvanian of Grand'Croix (Central massif, France) provides evidence for the mycorrhizal status of Radiculites-type Cordaitalean rootlets. These rootlets are characterized by a cortical reticulum of cell wall thickenings named phi-thickenings. This lignified reticulum is an important feature used to distinguish Cordaitalean rootlets from underground parts of other plants. As a result, our study demonstrates the oldest evidence for mycorrhizal association in the conifer clade.

  5. Lithostratigraphy and paleoenvironmental reconstructions for Devonian strata in the Michigan Basin

    SciTech Connect

    Harrison, W.B. III . Dept. of Geology)

    1994-04-01

    Devonian strata in the Michigan Basin are represented by variably thick sequences of open shelf, tidal flat and sabhka carbonates, interbedded with basin-centered and sabhka evaporites (anhydrite and halite). Although there are isolated outcrops around the margins of the basin, the lithofacies relationships of these strata can be best studied from subsurface data of cores, wireline logs, and drill cutting samples. This database is compiled from over 25,000 oil and gas wells that enter or entirely penetrate Devonian strata in Michigan. Most of the strata in the Michigan Basin Devonian are part of the Kaskaskia cratonic depositional sequence (Sloss, 1963). The sequence begins with the southeast to northwest transgression of a quartz arenite (Sylvania Ss.) sandstone facies onto a weathered, cherty carbonate (Bois Blanc Fm.) surface developed on Lower Devonian strata exposed during the post-Tippecanoe unconformity. With rising sea level, the basin sediments became dominated by open shelf, biohermal and locally restricted lagoon carbonates (Amherstberg Fm.). Much of the Middle Devonian is represented by thick basin-centered sabhka and salina evaporates and restricted-environment carbonates (Lucas Fm.). These interbedded and laterally gradational evaporite/carbonate facies are cyclic, showing gradual salinity changes during accumulation. Stratigraphically important K-Bentonite marker beds are prevalent in this part of the Michigan section. Overlying this restricted sequence are again open shelf, biohermal, and local restricted sabhka carbonate deposits (Dundee Fm.). Thin, but widespread and eastwardly thickening, terrigenous shales and mudstones are intercalated within another shelf carbonate package (Traverse Group). Devonian deposits in the Michigan Basin are capped by thick black shales and interbedded carbonates (Antrim Fm.).

  6. Seismic evaluation of the Devonian Ohio Shale in the Big Ugly area, southwestern West Virginia

    SciTech Connect

    Zheng Li; Wilson, T. )

    1991-08-01

    The Devonian Ohio Shale was studied in the Big Ugly area of southwestern West Virginia by reprocessing and interpreting existing seismic and geologic data. These data suggest the presence of detached structures above three decollement zones and cross-strike discontinuities associated with the Alleghanian deformation west of Mann Mountain anticline. A basement growth structure, the Griffithsville basement high, localized detached structures along its southeast flank. High producing trends of gas from the Devonian Ohio Shale occur either near northwest-trending cross-strike structural discontinuities or in the northeast-trending detached structures where fracture density should be increased.

  7. A case study of the evaluation, completion, and testing of a Devonian shale gas well

    SciTech Connect

    Lancaster, D.E.; Guldry, F.K.; Graham, R.L.; Curtis, J.B.; Shaw, J.S.

    1989-05-01

    This paper summarizes the operational procedures, geochemical analyses, well-log-interpretation techniques, perforation selection methodology, production-log interpretation, well-test analysis, and stimulation evaluation for a Devonian shale gas well in Pike County, KY. Contractors collected well-log, core, geochemical, and well-test data in addition to those which the operator would have routinely collected on this well. The purpose of this paper is to discuss the data collected on the well, to present the data analyses, and to demonstrate how the various analyses are being integrated to form a better overall understanding of Devonian shale gas reservoirs.

  8. Chemostratigraphic and U-Pb geochronologic constraints on carbon cycling across the Silurian-Devonian boundary

    NASA Astrophysics Data System (ADS)

    Husson, Jon M.; Schoene, Blair; Bluher, Sarah; Maloof, Adam C.

    2016-02-01

    The Devonian Period hosts extraordinary changes to Earth's biosphere. Land plants began their rise to prominence, with early vascular vegetation beginning its colonization of near-shore environments in the latest Silurian. Across the Silurian-Devonian (Pridoli-Lochkovian) transition, carbon isotope analyses of bulk marine carbonates (δC13carb) from Laurentian and Baltic successions reveal a positive δC13carb shift. Known as the Klonk Event, values reach + 5.8 ‰, making it one of the largest carbon isotope excursions in the Phanerozoic. Assigning rates and durations to these significant events requires a robust, precise Devonian time scale. Here we present 675 micritic matrix and 357 fossil-specific δC13carb analyses from the lower Devonian Helderberg Group of New York and West Virginia that exhibit the very positive δC13carb values observed in other Silurian-Devonian basins. This chemostratigraphic dataset is coupled with 66 ID-TIMS U-Pb dates on single zircons from six ash falls intercalated within Helderberg sediments, including dates on the stratigraphically lowest Devonian ashes yet developed. In this work, we (a) demonstrate that matrix and fossil-specific δC13carb values track one another closely in the Helderberg Group, (b) estimate the Silurian-Devonian boundary age in New York to be 421.3 ± 1.2 Ma (2σ; including decay constant uncertainties), and (c) calculate the time required to evolve from baseline to peak δC13carb values at the onset of the Klonk event to be 1.00 ± 0.25 Myr. Under these constraints, a steady-state perturbation to the global carbon cycle can explain the observed excursion with modern fluxes, as long as DIC concentration in the Devonian ocean remained below ∼2× the modern value. Therefore, potential drivers, such as enhanced burial of organic carbon, need not rely on anomalously high total fluxes of carbon to explain the Klonk Event.

  9. Geometry of an outcrop-scale duplex in Devonian flysch, Maine

    USGS Publications Warehouse

    Bradley, D.C.; Bradley, L.M.

    1994-01-01

    We describe an outcrop-scale duplex consisting of 211 exposed repetitions of a single bed. The duplex marks an early Acadian (Middle Devonian) oblique thrust zone in the Lower Devonian flysch of northern Maine. Detailed mapping at a scale of 1:8 has enabled us to measure accurately parameters such as horse length and thickness, ramp angles and displacements; we compare these and derivative values with those of published descriptions of duplexes, and with theoretical models. Shortening estimates based on line balancing are consistently smaller than two methods of area balancing, suggesting that layer-parallel shortening preceded thrusting. ?? 1994.

  10. Lower Devonian tentaculite bed in the Satun area, southern peninsular Thailand

    NASA Astrophysics Data System (ADS)

    Agematsu, Sachiko; Sashida, Katsuo; Salyapongse, Sirot; Sardsud, Apsorn

    2006-05-01

    A Lower Devonian (Emsian) tentaculite fauna including Nowakia acuaria [Richer, R., 1854. Thüringische Tentaculiten. Zeitschr. Deutsch. Geol. Gesellsch. 6, 275-290] occurs in black shale in the basal part of a siliciclastic sequence exposed north of Satun, southern peninsular Thailand. Similar tentaculite beds with Nowakia have been reported from several areas in the Fang, Sri Sawat, and Trang areas of Thailand, the Langkawi Islands and the Mahang-Baling areas of Malaysia. The depositional environments in which the tentaculite-bearing black shale accumulated extended from modern northern Thailand to northwestern Malaysia during the Early Devonian (Emsian).

  11. Book Review:

    NASA Astrophysics Data System (ADS)

    Hudson, R. P.

    1981-04-01

    In July 1976, some thirty young scientists and their lecturers were privileged to participate in a conference on "Metrology and the Fundamental Constants" at Varenna, this being the 68th course in the "Enrico Fermi International School of Physics". Now, at last, we are all privileged to share in that experience—to a large degree—with the appearance of the Proceedings, published last summer under the auspices of the Italian Physical Society. This rather massive volume (800 pages) places in one's hands a summary of the "state of the art" in the greater part of physical metrology. It is not, however, a metrology handbook, designed to assist the unskilled in making trustworthy measurements. It summarizes, via the lectures of internationally-recognized experts, the most recent attempts to realize with enhanced accuracy the basic units of measurement and, in so doing, it presents the subject of measurement science as the central (or all-pervasive) topic in physics itself. Clearly demonstrated is the progress from discovery to "understanding" of physical phenomena which is made possible through the historical alternation of observation and measurement. The volume includes informative reviews of the fundamentals of this fundamental science, namely, the concepts of quantities and units (Allisy); systems of units and the Système International, SI. (Terrien); international aspects of metrology and standards (Terrien); practical considerations in a hierarchy of standards (Terrien); materials problems affecting metrology (Ferro Milone and Sourdo) and statistical methods (Allisy). These discussions alone, being brought together in one place, are of particular usefulness. The remaining, and major, part of the book is taken up by authoritative and generally very readable discussions of measurement topics, for the most part separately focused on one of the base units. For these one cannot help noticing nor refrain from recording a measure of imbalance: some quantities (for

  12. Bimodal Silurian and Lower Devonian volcanic rock assemblages in the Machias-Eastport area, Maine

    USGS Publications Warehouse

    Gates, Olcott; Moench, R.H.

    1981-01-01

    Exposed in the Machias-Eastport area of southeastern Maine is the thickest (at least 8,000 m), best exposed, best dated, and most nearly complete succession of Silurian and Lower Devonian volcanic strata in the coastal volcanic belt, remnants of which crop out along the coasts of southern New Brunswick, Canada, and southeastern New England in the United States. The volcanics were erupted through the 600-700-million-year-old Avalonian sialic basement. To test the possibility that this volcanic belt was a magmatic arc above a subduction zone prior to presumed Acadian continental collision, samples representing the entire section in the Machias-Eastport area of Maine were chemically analyzed. Three strongly bimodal assemblages of volcanic rocks and associated intrusives are recognized, herein called the Silurian, older Devonian, and younger Devonian assemblages. The Silurian assemblage contains typically nonporphyritic high-alumina tholeiitic basalts, basaltic andesites, and diabase of continental characterand calc-alkalic rhyolites, silicic dacites, and one known dike of andesite. These rocks are associated with fossiliferous, predominantly marine strata of the Quoddy, Dennys, and Edmunds Formations, and the Leighton Formation of the Pembroke Group (the stratigraphic rank of both is revised herein for the Machias-Eastport area), all of Silurian age. The shallow marine Hersey Formation (stratigraphic rank also revised herein) of the Pembroke Group, of latest Silurian age (and possibly earliest Devonian, as suggested by an ostracode fauna), contains no known volcanics; and it evidently was deposited during a volcanic hiatus that immediately preceded emergence of the coastal volcanic belt and the eruption of the older Devonian assemblage. The older Devonian assemblage, in the lagoonal to subaerial Lower Devonian Eastport Formation, contains tholeiitic basalts and basaltic andesites, typically with abundant plagioclase phenocrysts and typically richer in iron and

  13. Books To Grow By.

    ERIC Educational Resources Information Center

    Keeshan, Bob, Comp.

    Compiled by Bob Keeshan, TV's "Captain Kangaroo," this book is a reference guide for books appropriate for children through age eight. Books are organized alphabetically, according to children's age group, and include Bob Keeshan's comments as well as author, publisher, publishing date, and price. Each entry also lists values the book teaches,…

  14. Books for Babies.

    ERIC Educational Resources Information Center

    Corsaro, Julie

    1998-01-01

    Offers a list of more than 50 books, in picture book and board book format, that are best suited to the developmental needs and interests of infants and preschool children. Books are listed under the following headings: identification of objects, rhythm and rhyme, pattern and repetition, and contrast and opposition. (AEF)

  15. Writing a book review.

    PubMed

    Bryson, David; Hudson, Robert

    2017-04-01

    Book reviews are a good way to get started with writing for a journal and this Learning and CPD activity takes you through the process of understanding the aims of book review, undertaking practice pieces through to reviewing a book and advice on the dos and don'ts of book reviewing.

  16. Books To Grow By.

    ERIC Educational Resources Information Center

    Keeshan, Bob, Comp.

    Compiled by Bob Keeshan, TV's "Captain Kangaroo," this book is a reference guide for books appropriate for children through age eight. Books are organized alphabetically, according to children's age group, and include Bob Keeshan's comments as well as author, publisher, publishing date, and price. Each entry also lists values the book teaches,…

  17. Book Review:

    NASA Astrophysics Data System (ADS)

    Sanders, J. H.

    1984-01-01

    The NATO Advanced Study Institute held at Erice, Sicily, in November 1981 brought together specialists in precise measurement to present a tutorial introduction to quantum metrology and the measurement of the fundamental physical constants. Ever since the evolution of experimental physics as a scientific pursuit the measurement of the values of quantities accepted to be constants of nature has commanded the attention of some of the world's most accomplished workers in this field. Their efforts to seek out the sources of systematic error and to reduce the random errors have produced significant advances in techniques and a continual interest in their results from users and critics: as Raymond T Birge, who pioneered the evaluation of the 'best' values of the constants from the available measurements, observed (perhaps with tongue-in-cheek) "it is the continual variation in the values of these quantities that furnishes most of the interest in the subject". Long before the recognition of the fundamental constants the measurement of mass, length and time grew as a matter of necessity in organized communities, especially in agriculture, commerce and navigation. The adoption of standards, first local, then national, and now international, was a natural consequence. It is particularly relevant that the published proceedings of the NATO school opens with a historical survey by Pierre Giacomo of the Bureau International des Poids et Mesures, which places the subsequent papers in perspective. Measurements which realize the standards of length and time, and those from which values of the fundamental constants are derived, are of such a nature that a considerable background knowledge of physics is needed for their understanding. (The principle of the caesium frequency standard and the physics of the Josephson junction are a long haul from Michelson's measurement of the speed of light and the Millikan oil drop experiment familiar in the school books.) With this in mind, George

  18. Book Review:

    NASA Astrophysics Data System (ADS)

    Swenson, C. A.

    1984-01-01

    whole, although the discussions may be too detailed for the casual reader (who need read only the introduction and conclusions) and yet without sufficient detail for the person who requires a basic understanding (who then will consult the citations). Although he cannot anticipate the recommendations of the CCT for a new international temperature scale, the clues certainly are present in the discussions which he gives. Most important are the descriptions of the deviations of the IPTS-68 from thermodynamic temperatures, the limitations of thermocouples, and the need, which currently is met by the provisionally adopted EPT-76, for an extension of the international scale to temperatures below 13.8 K. I am pleased to have this monograph available and anticipate making good use of it. Over the past several years I often have felt the need for a resource book to answer general questions or to obtain an introduction to an unfamiliar area of temperature measurement, and regret very much that "Temperature" was not available earlier. This monograph undoubtedly will be a necessity for any laboratory where thermodynamic measurements are carried out and thermometers are used as serious tools. A great deal of basic and developmental work has been done on thermometry in the past ten years or so, probably considerably more than remains to be done in many areas of the temperature scale. The publication of "Temperature" is timely in this respect, and it should have a long, useful life as a standard reference. The author may consider a second edition when a new international temperature scale is adopted, but there will be few corrections and only relatively minor changes and additions beyond the details of the new scale.

  19. Allometric growth in the extant coelacanth lung during ontogenetic development.

    PubMed

    Cupello, Camila; Brito, Paulo M; Herbin, Marc; Meunier, François J; Janvier, Philippe; Dutel, Hugo; Clément, Gaël

    2015-09-15

    Coelacanths are lobe-finned fishes known from the Devonian to Recent that were long considered extinct, until the discovery of two living species in deep marine waters of the Mozambique Channel and Sulawesi. Despite extensive studies, the pulmonary system of extant coelacanths has not been fully investigated. Here we confirm the presence of a lung and discuss its allometric growth in Latimeria chalumnae, based on a unique ontogenetic series. Our results demonstrate the presence of a potentially functional, well-developed lung in the earliest known coelacanth embryo, and its arrested growth at later ontogenetic stages, when the lung is clearly vestigial. The parallel development of a fatty organ for buoyancy control suggests a unique adaptation to deep-water environments. Furthermore, we provide the first evidence for the presence of small, hard, flexible plates around the lung in L. chalumnae, and consider them homologous to the plates of the 'calcified lung' of fossil coelacanths.

  20. Allometric growth in the extant coelacanth lung during ontogenetic development

    PubMed Central

    Cupello, Camila; Brito, Paulo M.; Herbin, Marc; Meunier, François J; Janvier, Philippe; Dutel, Hugo; Clément, Gaël

    2015-01-01

    Coelacanths are lobe-finned fishes known from the Devonian to Recent that were long considered extinct, until the discovery of two living species in deep marine waters of the Mozambique Channel and Sulawesi. Despite extensive studies, the pulmonary system of extant coelacanths has not been fully investigated. Here we confirm the presence of a lung and discuss its allometric growth in Latimeria chalumnae, based on a unique ontogenetic series. Our results demonstrate the presence of a potentially functional, well-developed lung in the earliest known coelacanth embryo, and its arrested growth at later ontogenetic stages, when the lung is clearly vestigial. The parallel development of a fatty organ for buoyancy control suggests a unique adaptation to deep-water environments. Furthermore, we provide the first evidence for the presence of small, hard, flexible plates around the lung in L. chalumnae, and consider them homologous to the plates of the ‘calcified lung' of fossil coelacanths. PMID:26372119

  1. Devonian shales of central Appalachian basin: geological controls on gas production

    SciTech Connect

    Lowry, P.H.; Hamilton-Smith, T.; Peterson, R.M. )

    1989-03-01

    Gas reserves of the Devonian shales of the Appalachian basin constitute a large, underdeveloped resource producing from fractured reservoirs. As part of ongoing Gas Research Institute research, K and A Energy Consultants, Inc., is identifying geological controls on gas production. Preliminary findings indicate that local gas production is controlled by a combination of structure and stratigraphy. Regional geological review indicates that Devonian sedimentation and structure is influenced by repeated reactivation of basement faults. Site-specific geologic studies indicate that depositional and structural mechanisms vary substantially throughout the basin. Gas production on the eastern margin of the producing area is controlled by an Alleghenian thrust front located by Grenville normal faults. High-capacity wells are associated with tear faults in the thrust sheets. To the southwest, deformation is controlled by both Grenville and Rome trough basement faults. Reactivation of these faults during later orogenic events produced a complex of high-angle reverse and strike-slip faults. Fracturing in the Devonian shales is produced by shearing and flexure associated with these structures. Syndepositional movement of the basement structures influenced the deposition of coarser grained turbidites and tempestites. The combination of fractures and coarser clastic beds provides effective reservoir systems. The shale contains abundant organic material consisting of terrestrial plant debris and marine algal remains. Thermal maturation of this material produced gas which charged the lower reservoir systems. Exploration along reactivated structural trends is an effective strategy for locating Devonian shale gas accumulations. This approach may also apply to other producing strata in the basin.

  2. Diagenetically altered stable isotope values from petrographically pristine brachiopods: lower Devonian Helderberg Group, New York State

    SciTech Connect

    Rush, P.F.; Chafetz, H.S.

    1988-02-01

    Brachiopods in the Devonian Helderberg Group carbonates and overlying Oriskany Sandstone are preserved with either an unaltered fabric which exhibits extremely fine preservation of original texture, or as neomorphosed coarsely crystalline bladed calcite. Petrographically pristine-looking as well as obviously neomorphosed brachiopods both display the same diagenetically altered carbon isotopic signatures. The carbon values of all skeletal components, including the petrographically well-preserved brachiopods, show a gradational change with stratigraphic distance beneath a Devonian unconformity. These values range from 2 to 3.5% PDB approximately 40 m below the unconformity to /minus/0.6 to 1.5% PDB immediately subjacent to the unconformity. Superjacent to the unconformity, brachiopods display an isotopic signature of 2.3 to 3.7% PDB, which is similar to values observed well below the unconformity. Diagenesis of the skeletal material must have occurred in contact with a meteoric system during the Siegenian (Lower Devonian) exposure. Of greater significance, petrographically pristine brachiopods have not retained their original carbon signature; instead these brachiopods have equilibrated with lighter meteoric waters without any visible change in their skeletal ultrastructure. This analysis was performed on the Lower Devonian Helderberg Group of central New York State, an accumulation of paralic to shallow open marine carbonates deposited on a shallow gradient ramp in a slowly subsiding (1.5 cm/1000 yrs) foreland basin.

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

    PubMed Central

    Sallan, Lauren Cole; Coates, Michael I.

    2010-01-01

    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. PMID:20479258

  4. Domal structure in Devonian rocks of Kimberling basin, Bland County, Virginia

    SciTech Connect

    McDowell, R.C.

    1988-08-01

    The Kimberling basin, which is floored with Middle Devonian clastic rocks, is a topographic and structural low in the Narrows fault block of the southern Appalachian Valley and Ridge province in Bland County, Virginia. The basin is bounded on the northwest and southeast by the southeast-dipping Narrows and Saltville thrust faults, respectively. Two doubly plunging anticlines lie along the strike of the basin. Lower Ordovician rocks are exposed in the Burkes Garden dome to the southwest, and Lower Cambrian rocks are present in the core of the Bane dome to the northeast. Previous workers have postulated continuity between the Burkes Garden and Bane domes through the Kimberling basin, as well as the presence in the basin of an anomalously thick Devonian clastic section, which has been ascribed by some authors to contemporaneous downwarp of a depositional syncline. Recent mapping has shown both of these postulates to be incorrect. The basin contains an anticline-syncline pair that is en echelon with the axes of the Burkes Garden and Bane anticlines and that trends about 20/degree/ more northerly than the regional strike of the bounding thrusts. Rediscovery of small outcrops of Lower and Middle Devonian Huntersville Chert and Rocky Gap Sandstone in the core of the Kimberling basin anticline, which were recorded by M.R. Campbell in 1896 but overlooked by later mappers, shows that the Devonian clastic sequence has a normal thickness and that the Kimberling basin contains a domal structure similar to the Burkes Garden and Bane domes.

  5. Occurrence of oil and gas in Devonian shales and equivalents in West Virginia

    SciTech Connect

    Schwietering, J. F.

    1981-03-01

    During the Devonian, an epicontinental sea was present in the Appalachian basin. The Catskill Clastic Wedge was formed in the eastern part of the basin by sediments derived from land along the margin of the continent. Three facies are recognized in the Catskill Clastic Wedge: (1) a red-bed facies deposited in terrestrial and nearshore marine environments; (2) a gray shale and sandstone facies deposited in a shallow- to moderately-deep marine environment; and (3) a dark-gray shale and siltstone facies deposited in the deepest part of the epicontinental sea. Oil and natural gas are being produced from Devonian shales in the western part of West Virginia and from upper Devonian sandstones and siltstones in the north-central part of the state. It is suggested that in addition to extending known areas of gas production, that drilling for natural gas be conducted in areas underlain by organic-rich shales and thick zones of interbedded siltstone and shale in the Devonian section in central, southern, and western West Virginia. The most promising areas for exploration are those areas where fractures are associated with folds, faults, and lineaments. 60 references.

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

    PubMed

    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.

  7. Succession of rugose coral faunas in the Lower and Middle Devonian of eastern North America

    USGS Publications Warehouse

    Oliver, William Albert

    1967-01-01

    The late Onesquethaw (Onondaga) faunas are the largest and most widely distributed of all those under review. Succeeding faunas of the Cazenovia, Tioughnioga and Taghanic Stage (Hamilton-Tully sequence) are less widespread and are clearly derivatives of the late Onesquethaw fauna. The Taghanic fauna is the latest Middle Devonian rugose coral fauna in the area

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

    NASA Astrophysics Data System (ADS)

    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.

  9. Ice-house-like orbital forcing of a mid-Devonian Ecosystem (Orcadian Basin, Scotland)

    NASA Astrophysics Data System (ADS)

    Whiteside, J. H.; Grogan, D. S.

    2010-12-01

    The middle Devonian witnessed the terrestrialization of plants and the radiation of fishes, two events upon which the climatic conditions have profound implications. However, recent oxygen isotopic data have challenged traditional assumptions of ice-free greenhouse conditions through the early and middle Devonian. Glaciation during icehouse times imparts distinctive frequency spectra on low-latitude climate records due to the high-latitude glacial control on global climates. Here we analyze gamma ray data from >350m of the Caithness Flagstone Group of the Orcadian Basin in North Scotland that cover ˜1.8 million years of the Middle Devonian (Givetian/Eifelian boundary) at 15 - 30° N. The repetitive facies assemblages have been interpreted to represent transitions between perennial lacustrine environments, and ephemeral playa or sub-aerial floodplain conditions. Fourier techniques, wavelet analysis, and a novel “pure sine model” technique reveal the full spectrum of sub-precessional to long eccentricity Milankovitch cycles. The presence of spectral power in the obliquity band (~40 kyr), unexpected at low latitudes during hothouse climate regimes, indicates a high-latitude influence on low-latitude climate, potentially amplified by ice sheets, or an as of yet unexplained insolation forcing mechanism. These data strongly support the idea of an ice-house climate during the middle Devonian.

  10. Lung Transplant

    MedlinePlus

    Lung transplant Overview By Mayo Clinic Staff A lung transplant is a surgical procedure to replace a diseased or ... lung, usually from a deceased donor. A lung transplant is reserved for people who have tried other ...

  11. Lung surgery

    MedlinePlus

    ... lung tissue that is diseased or damaged from emphysema or bronchiectasis Remove blood or blood clots ( hemothorax ) ... Editorial team. Related MedlinePlus Health Topics Collapsed Lung Emphysema Lung Cancer Lung Diseases Pleural Disorders Browse the ...

  12. Lung Emergencies

    MedlinePlus

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Lung Emergencies People with Marfan syndrome can be at ... should be considered an emergency. Symptoms of sudden lung collapse (pneumothorax) Symptoms of a sudden lung collapse ...

  13. Lung Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Lung Cancer What is Lung Cancer? How Tumors Form The body is made ... button on your keyboard.) Two Major Types of Lung Cancer There are two major types of lung ...

  14. Manetoe facies-a gas-bearing, megacrystalline, Devonian dolomite, Yukon and Northwest Territories, Canada

    SciTech Connect

    Morrow, D.W.; Cumming, G.L.; Koepnick, R.B.

    1986-06-01

    The Manetoe facies is a broadly stratiform and regionally developed (38,000 km/sup 2/ or 15,000 mi/sup 2/) body of white sparry dolomite hosted in Lower and Middle Devonian strata, and is the northwestward continuation of the similar, but better known. Presqu'ile facies dolomite. Several large gas fields have been discovered within anomalously thick developments of the Manetoe dolomite close to the northwest limit of the Devonian Elk Point basin of Alberta. The external geometry of the Manetoe facies indicates that it may have been a cavern or karst system excavated in the late Middle Devonian by a large, vertically confined coastal aquifer. The local regions of anomalously thick Manetoe facies may have developed where the aquifer stopped upward into strata above the confining aquiclude of the Headless Formation shale. Dolomite cementation may have occurred during any of three possible episodes of large-scale fluid movement. Fluid-inclusion and strontium isotope data favor the hypothesis that Manetoe dolomites precipitated from heated (150/sup 0/-210/sup 0/C or 300/sup 0/-410/sup 0/F) hypersaline evaporitic brines that have interacted with the underlying Precambrian crust, probably in the late Devonian. Lead-isotope data support the general concept of pre-Mesozoic dolomite cementation, and largely preclude a late Early Tertiary deep burial setting. Spectacular zones of detrital dolomite cement within the Manetoe are most readily accommodated by a near-surface, very early Middle Devonian aquifer mixing-model origin, but the presence of these zones does not preclude the other possible origins. Carbon and oxygen isotope data from the Manetoe facies support the concept that the Presqu'ile and Manetoe facies are physically continuous and lead a common origin.

  15. A Devonian paleomagnetic pole from red beds of the Tarim Block, China

    SciTech Connect

    Li, Yianping; McWilliams, M.; Sharps, R.; Cox, A. ); Li, Yongan; Li, Qiang; Gao, Zhengjia ); Zhang, Zhengkun ); Zhai, Yongjian )

    1990-11-10

    The authors present new Devonian paleomagnetic results from 59 sites in three stratigraphic sections exposed on the northwestern margin of the Tarim Block. At one section, 1,998 m of red sandstone is continuously exposed; the other two sections can be correlated with the first on both magnetostratigraphic and lithologic grounds. Progressive thermal demagnetization reveals three characteristic magnetizations. One is a Late Permian overprint which is isolated below 578C at sites near contacts with Late Permian dikes. The other two components are approximately antipodal, have a much higher unblocking temperature than the overprint, and are directionally distinct from the Late Permian overprint. They believe that these are characteristic Devonian magnetizations. Within the continuous 1,998 m section, results denote a 395 m reversed polarity zone overlying a 1,603 m normal polarity zone. One reversed event is recorded at the base of the section. A paleomagnetic pole calculated by averaging results from 47 normal and reversed sites lies at {lambda}{sub p}=16.5{degree}N, {phi}{sub p}=165.0{degree}E, K=25, and A{sub 95}=4.3{degree}. This pole is statistically distinct from a previously reported Late Devonian pole for Tarim. On the basis of field geologic and rock magnetic studies, they believe that the previously reported pole, in addition to results from one of their three sections, reflects at least partial contamination in the form of a thermal overprint caused by Late Permian igneous activity. An analysis of Devonian to Late Carboniferous polar wander suggests that the Tarim Block was attached to a subducting plate, and moved northward and rotated clockwise during the late Paleozoic. Comparison of the Devonian paleolatitudes of Siberian, Kazakhstan, Tarim and South China Blocks indicates that both the Tarim and South China Blocks were located in equatorial regions and were far south of the northern Angaran plate (Siberia and Kazakhstan).

  16. Intergrated study of the Devonian-age black shales in eastern Ohio. Final report

    SciTech Connect

    Gray, J.D.; Struble, R.A.; Carlton, R.W.; Hodges, D.A.; Honeycutt, F.M.; Kingsbury, R.H.; Knapp, N.F.; Majchszak, F.L.; Stith, D.A.

    1982-09-01

    This integrated study of the Devonian-age shales in eastern Ohio by the Ohio Department of Natural Resources, Division of Geological Survey is part of the Eastern Gas Shales Project sponsored by the US Department of Energy. The six areas of research included in the study are: (1) detailed stratigraphic mapping, (2) detailed structure mapping, (3) mineralogic and petrographic characterization, (4) geochemical characterization, (5) fracture trace and lineament analysis, and (6) a gas-show monitoring program. The data generated by the study provide a basis for assessing the most promising stratigraphic horizons for occurrences of natural gas within the Devonian shale sequence and the most favorable geographic areas of the state for natural gas exploration and should be useful in the planning and design of production-stimulation techniques. Four major radioactive units in the Devonian shale sequence are believed to be important source rocks and reservoir beds for natural gas. In order of potential for development as an unconventional gas resource, they are (1) lower and upper radioactive facies of the Huron Shale Member of the Ohio Shale, (2) upper Olentangy Shale (Rhinestreet facies equivalent), (3) Cleveland Shale Member of the Ohio Shale, and (4) lower Olentangy Shale (Marcellus facies equivalent). These primary exploration targets are recommended on the basis of areal distribution, net thickness of radioactive shale, shows of natural gas, and drilling depth to the radioactive unit. Fracture trends indicate prospective areas for Devonian shale reservoirs. Good geological prospects in the Devonian shales should be located where the fracture trends coincide with thick sequences of organic-rich highly radioactive shale.

  17. Conodont zonation and the Devonian/Carboniferous (Famennian/Tournaisian) boundary in the Naltaş section, eastern Taurides, Turkey

    NASA Astrophysics Data System (ADS)

    Atakul-Özdemir, Ayşe

    2017-02-01

    Conodont faunas from the Devonian/Carboniferous Naltaş section (eastern Taurides, Turkey) are presented. The faunas include important marker species of the latest Devonian earliest Carboniferous interval, belonging to the genera Siphonodella, Bispathodus, Polygnathus, Pseudopolygnathus, Apatognathus and Branmehla. Four conodont zones, comparable to the standard conodont zonation, are established in the studied succession, from the oldest to the youngest: (1) Bispathodus ultimus, (2) Siphonodella praesulcata Zones (Upper Famennian), (3) Siphonodella sulcata and (4) Siphonodella bransoni Zones (Lower Tournaisian). The Devonian/Carboniferous boundary in the eastern Taurides is recognized by the first appearance of Siphonodella sulcata.

  18. Astronomical Book Trek: Astronomy Books of 1983.

    ERIC Educational Resources Information Center

    Fraknoi, Andrew

    1984-01-01

    Presents an annotated list of technical and non-technical astronomy books. Topic areas of non-technical books include general astronomy, amateur astronomy, computers and astronomy, history of astronomy, pseudoscience, space exploration, physics and astronomy, and textbooks. Each entry includes author, title, description, source, and current cost.…

  19. Discis Books: Interactive Computer Books for Children.

    ERIC Educational Resources Information Center

    TechTrends, 1990

    1990-01-01

    Describes children's books available on CD-ROM that can be read using Apple Macintosh computers. Literacy problems with adults and children are discussed, the use of Discis books to encourage reading and improve understanding is described, first- and second-language learning is discussed, and a list of currently available titles is provided. (LRW)

  20. Views on Science Books.

    ERIC Educational Resources Information Center

    Gagne, Sarah

    1980-01-01

    Describes five new children's books about animals and other books about the development of anesthetics, the effects of bacteria, and the discovery of pheromones (scent chemicals that facilitate communication between members of an animal species). (GT)

  1. Looking into Tunnel Books.

    ERIC Educational Resources Information Center

    Hinshaw, Craig

    1999-01-01

    Describes how to make tunnel books, which are viewed by looking into a "tunnel" created by accordion-folded expanding sides. Suggests possible themes. Describes how to create a walk-through tunnel book for first grade students. (CMK)

  2. Views on Science Books.

    ERIC Educational Resources Information Center

    Gagne, Sarah

    1980-01-01

    Describes five new children's books about animals and other books about the development of anesthetics, the effects of bacteria, and the discovery of pheromones (scent chemicals that facilitate communication between members of an animal species). (GT)

  3. Picture Books for Teens.

    ERIC Educational Resources Information Center

    Kan, Kat

    2002-01-01

    Discusses picture books that are suitable for teens, particularly middle school readers, and provides detailed reviews for five titles that have appealing story themes and illustrations including: Tony Millionaires' Sock Monkey: A Children's Book; Mick Foley's Christmas Chaos; Mick Foley's Halloween Hijinx; The Book of Jack; and Moby Dick. (LRW)

  4. Children Talking about Books.

    ERIC Educational Resources Information Center

    Borders, Sarah G.; Naylor, Alice Phoebe

    In an effort to demonstrate how quality literature can engage children in reflective thinking about stories, themselves, and the world, this book suggests children's literature worthy of discussion, shows how interactions work, and encourages adults to bond with children. The book begins with a chapter on how to use the book and a chapter on the…

  5. The Book of Luck.

    ERIC Educational Resources Information Center

    Young, Carol

    2002-01-01

    Describes an art project that focused on the supernatural in which students create their own "Book Of Luck" using plastic videocassette containers. Discusses how each student created a book and the types of things that were included in the book. Includes examples. (CMK)

  6. Notable Canadian Children's Books.

    ERIC Educational Resources Information Center

    Aubrey, Irene E.

    This annotated bibliography dealing with Canadian children's books aims to show the historical development of the literature. Included within the bibliography are: (1) notable Canadian books from the eighteenth century to the modern period, (2) lists of books which were awarded a bronze medal for the years 1947-1975, and (3) a list of fiction for…

  7. The Electronic Book.

    ERIC Educational Resources Information Center

    Blake, Katie

    1988-01-01

    Discusses the development of the Smart Book, a device which simplifies access to information normally found in printed form, and describes its two distinct components--the reader unit containing computer equipment, display screen, and controls, and the ROM book pack containing the text of the book and program functions. Possible applications are…

  8. "It's Alive!": Science Books.

    ERIC Educational Resources Information Center

    Jordan, Anne Devereaux

    1997-01-01

    Sketches the history of children's books about science, from the first picture book in Germany in 1658 to Louis Agassiz's work on establishing science firmly in the education of young people in America. States that science books need to be accurate, and they must demonstrate the "scientific method." Outlines 11 characteristics of science…

  9. Thinking outside the Book

    ERIC Educational Resources Information Center

    Eaton, Dolores E.

    2012-01-01

    A title, a cover, and pages with "substance" bound together--this is what the author's eighth-grade students decided were the essential elements of a book. There could be more, but no less. In art, one does judge a book by its cover. In this article, the author describes how her students created their books. (Contains 1 online resource.)

  10. Notable Canadian Children's Books.

    ERIC Educational Resources Information Center

    Aubrey, Irene E.

    This annotated bibliography dealing with Canadian children's books aims to show the historical development of the literature. Included within the bibliography are: (1) notable Canadian books from the eighteenth century to the modern period, (2) lists of books which were awarded a bronze medal for the years 1947-1975, and (3) a list of fiction for…

  11. Collecting Artists' Books.

    ERIC Educational Resources Information Center

    Dalberto, Janet

    1983-01-01

    Discussion of increase in library collections of artists' books (artwork conceived in book form and designed entirely by artists) highlights reasons to collect artists' books, major collections, establishing a collection, housing and preservation, organization, outreach, and networking. Collection policy and procedures of Virginia Commonwealth…

  12. The Book of Luck.

    ERIC Educational Resources Information Center

    Young, Carol

    2002-01-01

    Describes an art project that focused on the supernatural in which students create their own "Book Of Luck" using plastic videocassette containers. Discusses how each student created a book and the types of things that were included in the book. Includes examples. (CMK)

  13. Picture Books for Teens.

    ERIC Educational Resources Information Center

    Kan, Kat

    2002-01-01

    Discusses picture books that are suitable for teens, particularly middle school readers, and provides detailed reviews for five titles that have appealing story themes and illustrations including: Tony Millionaires' Sock Monkey: A Children's Book; Mick Foley's Christmas Chaos; Mick Foley's Halloween Hijinx; The Book of Jack; and Moby Dick. (LRW)

  14. Children's Books and Recordings.

    ERIC Educational Resources Information Center

    Rivkin, Mary; And Others

    1993-01-01

    Presents an annotated bibliography of books and audiotape recordings for children from infancy through the early elementary grades. The bibliography includes recordings of music and storytelling; books that tell fairy tales and old favorite stories; and books about such topics as mother-child relationships and pets. (BB)

  15. Supplementary Science Books

    ERIC Educational Resources Information Center

    Barney, LeRoy

    1972-01-01

    Recently a great number of books have been printed that are written and illustrated nicely and deal with sophisticated science content. Provides a list of such books in different science areas. Books are categorized as easy to read, medium difficulty, and challenging. (PS)

  16. Children Talking about Books.

    ERIC Educational Resources Information Center

    Borders, Sarah G.; Naylor, Alice Phoebe

    In an effort to demonstrate how quality literature can engage children in reflective thinking about stories, themselves, and the world, this book suggests children's literature worthy of discussion, shows how interactions work, and encourages adults to bond with children. The book begins with a chapter on how to use the book and a chapter on the…

  17. Bibliographies of Children's Books.

    ERIC Educational Resources Information Center

    Wilke, Janet Stoeger, Comp.

    This annotated guide is designed to provide assistance in the identification of resources useful in locating books about various subjects related to children or appropriate for various grade levels. The 17 sections include entries for 86 books and articles in and about the following areas: general subjects/all grade levels; best book lists;…

  18. Special Book Review Issue.

    ERIC Educational Resources Information Center

    Grauer, Barbara Ellman, Ed.; And Others

    1998-01-01

    Provides reviews of books dealing with all aspects of careers, including 8 books on dealing with change, 13 on career management, 4 on entrepreneurship, 3 guides and workbooks, 2 on assessment, 4 on resumes, and 1 biography. Includes 12 short reviews of books on career development issues and information such as publishers' addresses. (JOW)

  19. Canadian Books for Children.

    ERIC Educational Resources Information Center

    McDonough, Irma, Ed.

    The children's books listed and annotated in this book were selected by Canadian children's librarians; they represent the most informative and relevant books in print for children, providing knowledge and understanding of the Canadian environment and cultural milieu. Each entry indicates bibliographic information and availability.…

  20. Children's Books about Religion.

    ERIC Educational Resources Information Center

    Dole, Patricia Pearl

    Created to promote a mutual understanding and acceptance among various faiths and cultures throughout the world, this book is an annotated bibliography of religious children's books. It has almost 700 critical evaluations of books with distinct religious themes for children from preschool to middle school. Chapters are: (1) "Religion";…

  1. Late Devonian Anoxia Events in the Central Asian Orogenic Belt: a Global Phenomenon

    NASA Astrophysics Data System (ADS)

    Carmichael, S. K.; Waters, J. A.; Suttner, T. J.; Kido, E.; DeReuil, A. A.; Moore, L. M.; Batchelor, C. J.

    2013-12-01

    Atmospheric CO2 values decreased dramatically during the Middle Devonian due to the rapid rise of land plants. These changing environmental conditions resulted in widespread anoxia and extinction events throughout the Late Devonian, including the critical Kellwasser and Hangenberg anoxia events, which are associated with major mass extinctions at both the beginning and end of the Famennian Stage of the Late Devonian. Fammenian sediments in northwestern Xinjiang Province, China, represent a highly fossiliferous shallow marine setting associated with a Devonian oceanic island arc complex. Analysis of multiple geochemical proxies (such as U/Th, Ba, normalized P2O5, V/Cr, Zr), magnetic susceptibility, and mineralogical data (biogenic apatite and pyrite framboids) indicates that these Famennian sequences record not only the Upper Kellwasser Anoxic Event at the Frasnian/Famennian (F/F) boundary but also the rebound from the F/F extinction event. Preliminary evidence suggests that the Hangenberg Anoxic Event can also be recognized in the same sequence, although our biostratigraphic control is less precise. Previous studies of the Kellwasser and Hangenberg Events have been performed on continental shelf environments of Laurussia, Gondwana, Siberia, and South China. The Devonian formations of northwest Xinjiang in this study, however, are part of the Central Asian Orogenic Belt (CAOB), which is thought to have formed as part of a complex amalgamation of intra-oceanic island arcs and continental fragments prior to the end of the latest Carboniferous. These results allow us to confirm the presence of the Kellwasser and Hangenberg Events in the open oceanic part of Paleotethys, indicating that both events were global in scope. The presence of an abundant diverse Famennian fauna between these anoxia/extinction events suggests that the shallow marine ecosystems in the CAOB were somewhat protected due to their tectonic location and relative isolation within an open ocean system

  2. Paleomagnetic constraints on the paleogeography and oroclinal bending of the Devonian volcanic arc in Kazakhstan

    NASA Astrophysics Data System (ADS)

    Abrajevitch, Alexandra; Van der Voo, Rob; Levashova, Natalia M.; Bazhenov, Mikhail L.

    2007-08-01

    A prominent feature of the central part of the Ural-Mongol orogenic belt is a series of concentric horse-shoe shaped volcanic arcs, with the youngest arc on the inside. This structure was long-suspected to be an orocline, but unequivocal evidence for this was lacking, mainly because paleomagnetic results of suitable age from this area remained sparse, but also because their interpretation was not straightforward due to a long history of deformations associated with the protracted late Paleozoic assembly of Asia. Our paleomagnetic study of Middle Devonian basaltic and andesitic flows in southeastern Kazakhstan revealed two main components of magnetization. The primary nature of a high temperature magnetization (tilt corrected Dec = 286.5, Inc = 46.4, α95 = 7.8, k = 29.2, N = 13 sites) is supported by the presence of antipodal directions and a baked-contact test. We also isolated a post-folding overprint with an in situ mean direction Dec = 134.9, Inc = - 43.0 ( α95 = 4.9, k = 71.6, N = 13 sites). The age of this overprint can be estimated as Early Permian with a high degree of confidence. The declination of the overprint is seen to be deflected counter-clockwise by 100 ± 6° relative to the 290-Ma reference direction, indicating that the studied locality, similar to many other localities in the region, was affected by late-orogenic rotations. We use the overprint's deflection to correct the declination of the primary Devonian magnetization for these late-orogenic block-rotations. Declinations from other Silurian and Devonian paleomagnetic results in the subduction-related Devonian volcanic arc of Kazakhstan have been corrected for such rotations wherever the latter are reasonably well documented. Using corrected declinations as passive markers we restored the trend of the volcanic belt to its Devonian configuration. Our analysis indicates that the presently curved belt was nearly straight and NW-SE trending. This ˜ 1500 km long volcanic belt characterized the

  3. Linking Biogeochemical Cycles of Nitrogen and Oxygen in Euxinic Devonian Basins

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

    Berner’s 2009 reconstruction of Phanerozoic atmospheric pO2 (1) features an approximately 30% decline in O2 spanning the Lower to Upper Devonian, a period characterized by the emergence and expansion of terrestrial forest ecosystems and episodic high organic matter deposition now found as epicontinental basinal black shales. There is an apparent contradiction between high rates of organic matter burial coupled with an increasing areal extent of photosynthetic O2 production and declining levels of atmospheric O2. This study sought to resolve that contradiction by examining the role of terrestrial nitrgen in the development of anoxygenic photosynthetic ecosystems in euxinic Devonian basins utilizing stable isotope and biomarker analyses. By fixing C into biomass without producing O2 as a byproduct, sulfide-driven anoxygenic photosynthesis can serve to moderate the flux of O2 to the atmosphere generated by oxygenic photosynthesis (2). Sulfur isotope values indicate temporally and spatially widespread euxinia in Middle and Upper Devonian epeiric seas and the presence of isorenieratane, a biomarker for green sulfur bacteria, indicating that anoxygenic photosynthesis was also widespread. High levels of marine primary productivity and the consequent development a sulfidic water column in Middle and Upper Devonian epeiric basins were likely the result of the emergence of a substantial new source of fixed N. Modern lowland tropical forests are net exporters of N to aquatic systems and it is likely that warm, moist Devonian lowland forests featured a similar N biogeochemistry. Riverine and atmospheric deposition of terrestrial fixed N facilitated an increase in the relative contribution of anoxygenic photosynthesis to total global C fixation, resulting in the 30% pO2 decline over a period of about 30 million years. The Upper Devonian expansion of forests into upland and temperate environments, where the N excess seen in modern forests is uncommon, reversed the O2 decline

  4. The impact of astronomical forcing on the Late Devonian greenhouse climate

    NASA Astrophysics Data System (ADS)

    De Vleeschouwer, David; Crucifix, Michel; Bounceur, Nabila; Claeys, Philippe

    2014-05-01

    The geological record of the Paleozoic often exhibits cyclical or rhythmical characteristics, in many cases the result of cyclical changes in paleoclimate. However, a thorough understanding of the climatic processes that were driving Paleozoic climate change remains a challenge, for example because of relatively poor time-control on much of the Paleozoic paleoclimate archives. A good comprehension of the Paleozoic climate is crucial in order to grasp how the Earth's climate system works under conditions completely different than the ones of today. We apply Late Devonian (375 Ma) preconditions to the Hadley Centre general circulation model (HadSM3). In this work, we constrain the climatic steering role of the astronomical parameters, by keeping all other potential forcing factors (e.g. paleogeography, pCO2, vegetation distribution) fixed. Thirty-one different "snapshots" of Late Devonian climates were simulated, by running the model into steady-state with 31 different combinations of eccentricity, obliquity and precession. To assess the performance of the model, we confronted a simulated Late Devonian climate with a moderate astronomical forcing regime to lithic indicators of paleoclimate and oxygen-isotope paleothermometry. This model-data confrontation provides good comparison, indicating that the model succeeds in simulating reasonable climates for the Late Devonian. The different simulations demonstrate that the coldest and driest global climates occur under low obliquity and low eccentricity. Under low obliquity, northern hemispheric sea-ice can form and the Gondwanan winter snow cover reaches a maximal extent, triggering an albedo-feedback mechanism and thus global coolness. However, even those coolest global climates undergo too hot austral summers for continental ice to build up in the southern hemisphere. Tropical and monsoonal precipitation intensity demonstrates a strong direct dependence on precession-driven quantity of summer insolation. Temperature, on

  5. New thelodont findings from the Lower Devonian Andrée Land Group, Spitsbergen

    NASA Astrophysics Data System (ADS)

    Blom, H.; Žigaitė, Ž.

    2012-04-01

    During the last 50 years, ever since Ørvig (1957) described the first thelodont material from Sörkapp Land, have the amount of scales available from the Lower Devonian of Spitsbergen slowly increased to a body that clearly promotes an extended taxonomical and biostratigraphical revision. More recently, have thelodonts been described from a more stratigraphically controlled sequence of beds from the Red Bay Group (Blom and Goujet 2002). These Lochkovian (lowermost Devonian) taxa show a faunal differentiation which also allowed a detailed comparison between the Red Bay Group of Spitsbergen and sections of similar age from other parts of the Northern Hemisphere (Blom and Goujet 2002), supporting the suggested detailed biozonal subdivision of the Lochkovian deposits as presented by Talimaa (2000) based on distribution data from northern Eurasia. Although the stratigraphical framework of Spitsbergen is complicated, the Red Bay and Andrée Land groups have a well distributed fauna of thelodont scales that have been suggested to be the main reference of thelodont biozonation in the Pragian and Emsian (Talimaa 2000). We have examined a major part of thelodont collections comming from the region, including some newly collected samples. As a result, a biostratigraphic distribution of a number of well known thelodont taxa have been described from the Wood Bay and Grey Hoek formations in NW Spitsbergen. In addition, one new thelodont genus and two new species have been discovered. These data, together with known thelodont assemblages from the Canadian Arctic (Vieth 1980) and Severanya Zemlya (Karatajute-Talimaa 1978) allows us to speak about the usefulness of thelodonts in biostratigraphy and global correlation in the upper parts of the Lower Devonian. Blom, H. and Goujet, D. 2002. Thelodont scales from the Lower Devonian Red Bay Group, Spitsbergen. Palaeontology, 45(4): 795-820. Karatajūtė -Talimaa, V. N., 1978. Silurian and Devonian Thelodonts of the USSR and Spitsbergen

  6. Geologic controls on reservoir properties in gas-bearing middle and Upper Devonian rocks, southern Appalachian basin

    SciTech Connect

    Vessell, R.K.; Davies, D.K.

    1988-08-01

    Porosities and permeabilities have been measured for a wide range of nonfractured Devonian lithologies in 23 wells from southeastern Ohio, eastern Kentucky, West Virginia, and Virginia. These reservoir properties can be related directly to the geometry of the pore system. Pore geometry, in turn, is a function of rock lithology and mineralogy. Despite the lithologic complexity of the Devonian sequence, reservoir quality can be related to a small number of differing pore geometries.

  7. Thermal maturity patterns in the Ordovician and Devonian of Pennsylvania using conodont color alteration index (CAI) and vitrinite reflectance (%Ro)

    USGS Publications Warehouse

    Repetski, J.E.; Ryder, R.T.; Harper, J.A.; Trippi, M.H.

    2006-01-01

    This new series of maps enhances previous thermal maturity maps in Pennsylvania by establishing: 1) new subsurface CAI data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved CAI-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.

  8. Thermal maturity patterns (CAI and %R) in the Ordovician and Devonian rocks of the Appalachian basin in Pennsylvania

    USGS Publications Warehouse

    Repetski, John E.; Ryder, Robert T.; Harper, John A.; Trippi, Michael H.

    2002-01-01

    The objective of this study is to enhance existing thermal maturity maps in Pennsylvania by establishing: 1) new subsurface CAI data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones (Ryder and others, 1998) and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved CAI-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.

  9. Thermal maturity patterns (CAI and %R%) in the Ordovician and Devonian rocks of the Appalachian basin in New York State

    USGS Publications Warehouse

    Weary, David J.; Ryder, Robert T.; Nyahay, Richard

    2000-01-01

    The objective of this study is to enhance existing thermal maturity maps in New York State by establishing: 1) new subsurface CAI data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. The thermal maturity of the Ordovician and Devonian rocks is of major interest because they contain the source for most of the unconventional natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Group are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones (Jenden and others, 1993; Ryder and others, 1998). Improved CAI-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation, in particular, its basin-centered part (Ryder, 1998). Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulation in Upper Devonian sandstone and Middle to Upper Devonian black shale.

  10. Thermal maturity patterns (CAI and %Ro) in the Ordovician and Devonian rocks of the Appalachian basin in West Virginia

    USGS Publications Warehouse

    Repetski, John E.; Ryder, Robert T.; Avary, Katharine Lee; Trippi, Michael H.

    2005-01-01

    The objective of this study is to enhance existing thermal maturity maps in West Virginia by establishing: 1) new subsurface CAI data points for the Ordovician and Devonian and 2) new %Ro and Rock Eval subsurface data points for Middle and Upper Devonian black shale units. Thermal maturity values for the Ordovician and Devonian strata are of major interest because they contain the source rocks for most of the oil and natural gas resources in the basin. Thermal maturity patterns of the Middle Ordovician Trenton Limestone are evaluated here because they closely approximate those of the overlying Ordovician Utica Shale that is believed to be the source rock for the regional oil and gas accumulation in Lower Silurian sandstones (Ryder and others, 1998) and for natural gas fields in fractured dolomite reservoirs of the Ordovician Black River-Trenton Limestones. Improved CAI-based thermal maturity maps of the Ordovician are important to identify areas of optimum gas generation from the Utica Shale and to provide constraints for interpreting the origin of oil and gas in the Lower Silurian regional accumulation and Ordovician Black River-Trenton fields. Thermal maturity maps of the Devonian will better constrain burial history-petroleum generation models of the Utica Shale, as well as place limitations on the origin of regional oil and gas accumulations in Upper Devonian sandstone and Middle to Upper Devonian black shale.

  11. Astronomical Book Trek: Astronomy Books of 1982.

    ERIC Educational Resources Information Center

    Fraknoi, Andrew

    1983-01-01

    Provided in two separate annotated lists are technical and nontechnical astronomy books. Categories in the latter group include: general astronomy; astronomy textbooks; amateur astronomy; astronomy history; life on other worlds; astrophysics; the solar system; space exploration; and the sun. (JN)

  12. Astronomical Book Trek: Astronomy Books of 1982.

    ERIC Educational Resources Information Center

    Fraknoi, Andrew

    1983-01-01

    Provided in two separate annotated lists are technical and nontechnical astronomy books. Categories in the latter group include: general astronomy; astronomy textbooks; amateur astronomy; astronomy history; life on other worlds; astrophysics; the solar system; space exploration; and the sun. (JN)

  13. Early Devonian geothermal systems in northeast Scotland: Exploration targets for epithermal gold

    SciTech Connect

    Nicholson, K. )

    1989-06-01

    Early Devonian geothermal activity is recognized in northeast Scotland by the remnants of silica sinter, a hot-spring manganese deposit, an area of steam alteration, and hydrothermal eruption breccias. At least five systems were active at this time, three of which are located on or near the intersection of major faults and lineaments. Two deposits can be dated as Early Devonian, whereas others show a spatial relation to 408 Ma Caledonian granitoids-the proposed heat sources for the geothermal systems. Fault zones active at this time provided channelways for fluids in the convecting systems. The shallow sections of these systems have been preserved in the Arndilly, Dalroy, Lecht, and Rhynie areas, which is encouraging for gold prospecting. Six targets for epithermal gold exploration are identified: the four areas named above and two areas at the intersection of major faults and lineaments.

  14. Identification of reservoir characteristics in cased-wells Devonian shale. Topical report, October 1990

    SciTech Connect

    Guidry, F.K.; Raymer, L.L.

    1990-10-01

    Existing cased wells in the Devonian shale can be evaluated regardless of the availability of any previous open-hole logs. This will enable the operator to evaluate older wells for recompletion possibilities. Log models have been recently developed, based on extensive use of core analysis, for identifying reservoir characteristics in the open-hole. Using this knowledge and an understanding of the linkage of these characteristics minimum logging suites can be utilized in the evaluation of the Devonian shale. Using the extensive data set collected during the comprehensive study well (CSW) program, a method was developed for evaluating existing cased-hole wells. The methodology involves the use of several combinations of open and cased-hole logs. Although the evaluation results are more reliable where key open hole logs are available, acceptable results can be obtained even without any open hole log data.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

    Zatoń, Michał; Broda, Krzysztof; Qvarnström, Martin; Niedźwiedzki, Grzegorz; Ahlberg, Per Erik

    2017-04-01

    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 active predator or a scavenger, these finds provide the first direct evidence of feeding on conodont animals by early coelacanth fish, and one of the few evidences of feeding on these animals known to date. It also expands our knowledge about the diet and trophic relations between the Paleozoic marine animals in general.

  17. Upper Devonian transitional shale facies of western Appalachian basin of southeastern Ohio

    SciTech Connect

    Baranoski, M.T.; Riley, R.A.

    1987-09-01

    Transitional facies have been mapped in five Upper Devonian shale units using geophysical logs from southeastern Ohio. Each facies is a north-northeast-trending zone that parallels the paleodepositional strike of the Appalachian basin during the Late Devonian. The facies are defined by the interfingering of gray and greenish-gray siltstones and shales from the east with black shale from the west. Structure and isopach mapping indicate penecontemporaneous faulting and subsequent filling along faults with sediments in the form of coalescing lobate bodies. Penecontemporaneous faulting may be related to sediment loading of the Catskill delta. The relative position of the transitional facies may indicate the western penetration of far-distal turbidites of the Catskill delta into an anoxic portion of the Appalachian basin.

  18. Sedimentology of gas-bearing Devonian shales of the Appalachian Basin

    SciTech Connect

    Potter, P.E.; Maynard, J.B.; Pryor, W.A.

    1981-01-01

    The Eastern Gas Shales Project (1976-1981) of the US DOE has generated a large amount of information on Devonian shale, especially in the western and central parts of the Appalachian Basin (Morgantown Energy Technology Center, 1980). This report summarizes this information, emphasizing the sedimentology of the shales and how it is related to gas, oil, and uranium. This information is reported in a series of statements each followed by a brief summary of supporting evidence or discussion and, where interpretations differ from our own, we include them. We believe this format is the most efficient way to learn about the gas-bearing Devonian shales of the Appalachian Basin and have organized our statements as follows: paleogeography and basin analysis; lithology and internal stratigraphy; paleontology; mineralogy, petrology, and chemistry; and gas, oil, and uranium.

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

    PubMed

    Zatoń, Michał; Broda, Krzysztof; Qvarnström, Martin; Niedźwiedzki, Grzegorz; Ahlberg, Per Erik

    2017-04-01

    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 active predator or a scavenger, these finds provide the first direct evidence of feeding on conodont animals by early coelacanth fish, and one of the few evidences of feeding on these animals known to date. It also expands our knowledge about the diet and trophic relations between the Paleozoic marine animals in general.

  20. A Late Devonian Fertile Organ with Seed Plant Affinities from China

    PubMed Central

    Wang, Deming; Liu, Le; Guo, Yun; Xue, Jinzhuang; Meng, Meicen

    2015-01-01

    Seed plants underwent first major evolutionary radiation in the Late Devonian (Famennian), as evidenced by the numerous ovules described to date. However, the early pollen organs are underrepresented, so that their structure and evolution remain poorly known. Here we report a new taxon of pollen organ Placotheca minuta from the Late Devonian. The synangium consists of many basally and more or less laterally fused microsporangia borne on the margin of a pad. The prepollen is spherical and trilete. The appearance of Famennian synangia especially in Placotheca does not support the current understanding that the earliest pollen organs closely resembled the fructifications of the ancestral progymnosperms. Placotheca indicates earlier diversification of pollen organs than previously expected and is highly derived among the early pollen organs with trilete prepollen. It is suggested that, immediately after the origination of seed plants, pollen organs had evolved at a rapid rate, whereas their prepollen remained primitively spore-like. PMID:26022973

  1. Chemosynthetic microbialites in the Devonian carbonate mounds of Hamar Laghdad (Anti-Atlas, Morocco)

    NASA Astrophysics Data System (ADS)

    Cavalazzi, Barbara; Barbieri, Roberto; Ori, Gian Gabriele

    2007-08-01

    Veins cutting across the Devonian conical mounds of the Hamar Laghdad Ridge (eastern Anti-Atlas, Morocco) were the carriers of geofluids. Although not completely determined, the composition of these fluids seems related to hydrothermal and seepage fluxes that were the primary contributors to the establishment of sub-seafloor (cryptic) environments linking deeper fluid sources to the seafloor. The optical and scanning electron microscope investigation of the laminated carbonate infill of these veins has revealed that they consist of stromatolite- and oncolite-like fabrics. In the Early and Middle Devonian mounds, the laminated carbonates contain morphologies that are attributable to microbially mediated processes that in turn suggest a direct biological contribution to the deposition of the veins infill. Microbial evidence include rod-shaped and cocci clusters embedded in amorphous membranes, iron-rich filaments organized as mat-like and biodictyon filamentous aggregates, or isolated filaments, microbial clotted textures and peloids. Moreover, the oncoids from the veins of the Middle Devonian (Hollard) mound have been interpreted as the mineral replacement of crypto-microorganisms as Frutexites. Other microbial evidence are biominerals and include carbonate with spheroids and pyrite framboids, in which typifying hydrocarbon seep environments. The Hollard Mound, which is the only one with a well-documented origin by hydrocarbon seepage, shares a number of geomicrobiological evidence with other Early Devonian mounds. These evidence, which are supplemented by δ13C-depleted data, suggest that the infill of the veins system in the Hamar Laghdad mounds would be the product of chemotrophic/chemosynthetic microbial communities that are adapted to crypto-habitats sustained by hydrocarbon (and other components) fluid fluxes.

  2. Utility of palmatolepids and icriodontids in recognizing Upper Devonian Series, Stage, and possible substage boundaries

    USGS Publications Warehouse

    Ziegler, W.; Sandberg, C.A.

    2000-01-01

    Conodonts are accepted internationally to define Devonian Series and Stage boundaries. Hence, the evolution and taxonomy of pelagic palmatolepids, primarily Palmatolepis and its direct ancestor Mesotaxis, and shallow-water icriodontids, Icriodus, Pelekysgnathus, and "Icriodus", are the major tools for recognizing subdivisions of the Upper Devonian. Palmatolepids are the basis for the Late Devonian Standard Conodont Zonation (ZIEGLER & SANDBERG 1990), whereas icriodontids are the basis for the alternative, integrated shallow-water zonation (SANDBERG & DREESEN 1984). However, an alternative palmatolepid taxonomy for some Frasnian species has been employed recently by some conodont workers using the Montagne Noire (M.N.) zonation, shape analyses of Pa elements, and multielement reconstructions of KLAPPER (1989), KLAPPER & FOSTER (1993); and KLAPPER et al. (1996). Herein, the evolution of palmatolepids and icriodontids is summarized in terms of our zonation and some of the taxonomic differences with the alternative M.N. zonation are exemplified. One of the problems in relating the Standard and M.N. zonations arises from previous errors of interpretation and drafting of the Martenberg section in Germany. This section was designated the reference section for the Frasnian transitans through jamieae Zones by ZIEGLER & SANDBERG (1990). Herein, the early and middle Frasnian zonal boundaries at Martenberg are improved by re-study of our old and recent collections from three profiles, spaced only 4 m apart. Serious problems exist with the Global Stratotype Sections and Points (GSSP's), selected by the Subcommission on Devonian Stratigraphy, following the paleontologic definition of the bases of the Frasnian, Famennian, and Tournaisian Stages, because of the difficulty in making global correlations from these GSSP's. Our summary of these problems should be helpful if future workers decide to relocate these GSSP's.

  3. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements. Final report

    SciTech Connect

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  4. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements

    SciTech Connect

    Locke, C.D.; Salamy, S.P.

    1991-09-01

    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  5. Devonian shale gas exploration and production studies. Final report, November 1983-April 1986

    SciTech Connect

    Wallace, J.L.; Koziar, G.; Lemon, J.P.; Akers, M.J.

    1986-08-01

    Ten wells in southwestern West Virginia were selected as potential candidates for in-depth study to identify Devonian-shale-gas production-controlling mechanisms. Wells were studied using geophysical logs, TV log, and flow measurements. Sidewall cores were retrieved for geochemical and geophysical analyses. The well studies were augmented with a seismic survey, production data analysis and data collection for approximately 1400 wells in the study area.

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

    PubMed Central

    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

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Earth-atmosphere evolution based on new determination of Devonian atmosphere Ar isotopic composition

    NASA Astrophysics Data System (ADS)

    Stuart, Finlay M.; Mark, Darren F.; Gandanger, Pierre; McConville, Paul

    2016-07-01

    The isotopic composition of the noble gases, in particular Ar, in samples of ancient atmosphere trapped in rocks and minerals provides the strongest constraints on the timing and rate of Earth atmosphere formation by degassing of the Earth's interior. We have re-measured the isotopic composition of argon in the Rhynie chert from northeast Scotland using a high precision mass spectrometer in an effort to provide constraints on the composition of Devonian atmosphere. Irradiated chert samples yield 40Ar/36Ar ratios that are often below the modern atmosphere value. The data define a 40Ar/36Ar value of 289.5 ± 0.4 at K/36Ar = 0. Similarly low 40Ar/36Ar are measured in un-irradiated chert samples. The simplest explanation for the low 40Ar/36Ar is the preservation of Devonian atmosphere-derived Ar in the chert, with the intercept value in 40Ar-39Ar-36Ar space representing an upper limit. In this case the Earth's atmosphere has accumulated only 3% (5.1 ± 0.4 ×1016 mol) of the total 40Ar inventory since the Devonian. The average accumulation rate of 1.27 ± 0.09 ×108 mol40Ar/yr overlaps the rate over the last 800 kyr. This implies that there has been no resolvable temporal change in the outgassing rate of the Earth since the mid-Palaeozoic despite the likely episodicity of Ar degassing from the continental crust. Incorporating the new Devonian atmosphere 40Ar/36Ar into the Earth degassing model of Pujol et al. (2013) provides the most precise constraints on atmosphere formation so far. The atmosphere formed in the first ∼100 Ma after initial accretion during a catastrophic degassing episode. A significant volume of 40Ar did not start to accumulate in the atmosphere until after 4 Ga which implies that stable K-rich continental crust did not develop until this time.

  9. Using Picture Books Kindergarten through High School.

    ERIC Educational Resources Information Center

    Richardson, Maurine V.; Miller, Margaret B.

    A picture book is defined as a book in which the illustrations are as important as the text or written story. Picture books published today seem appropriate and exciting for anyone from 1 to 100 years old. Among the many kinds of picture books are Mother Goose books; toy books (board books, pop-up books, concept books, flap books, cloth books, and…

  10. Conodont colour alteration patterns in Devonian rocks of the eastern Anti-atlas, Morocco

    NASA Astrophysics Data System (ADS)

    Belka, Z.

    The thermal and burial history of the eastern Anti-Atlas during Late Palaeozoic time is investigated using conodont colour alteration data and the electron spin resonance technique (ESR). Both the conodont colour alteration index (CAI) patterns and the results of ESR investigations indicate that the Devonian rocks of the eastern Anti-Atlas attained their present-day maturation level during Carboniferous time prior to Variscan uplift. The observed CAI values from 3 to 5 reflect heating to temperatures of 120°C and 310°C respectively. The conodont CAI pattern observed in the Devonian rocks is a product of burial and loading by thick Carboniferous cover but the maturation level is too high to be accounted for by burial beneath the known stratigraphical overburden under normal heat flow conditions. The analysis of palaeotemperatures inferred from conodont CAI values shows variation in heat flow during Carboniferous time, with an average geothermal gradient of 30°C/km in the Béchar Basin and higher gradients in the region of the mader and Tafilalt. The style of the observed CAI patterns suggests that depositional trends in the Carboniferous cover, now largely removed by erosion, followed the Devonian subsidence patten.

  11. Late Devonian carbonate-conglomerate association in the Canning basin, Western Australia

    SciTech Connect

    Holmes, A.E. )

    1991-03-01

    Siliciclastic conglomerates of Late Devonian to Carboniferous age crop out discontinuously along the northern margin of the Canning basin in Western Australia, where they are associated with a classic example of reefal carbonate rocks. An understanding of these deposits is relevant to the timing of extension in the basin, uplift of the adjacent Kimberley block, and to the interpretation of the sequence stratigraphy of the carbonates. The conglomerates indicate that the Kimberley block was high-standing, even though most normal faulting appears to have ceased by Late Devonian time, and provided a continuous source of siliclastic material. The carbonate-conglomerate relationships were studied in detail at two localities, with brief visits to several other sections to provide a regional context. A sequence boundary of late Frasnian age is exposed at several localities. Incised valleys with 10 m relief (e.g. Van Emmerick and Mt. Elma) and onlapping relationships (e.g. Stony Creek, Van Emmerick) provide strong evidence for a type 1 boundary that likely formed during a eustatic base-level drop (cf., Devonian carbonates of Canada). The recognition of several intervals of siliciclastic conglomerate influx in the Canning basin is important because it suggests the presence of distal lowstand sandstone reservoirs that may represent potential petroleum targets.

  12. Early Devonian (Late Emsian) shark fin remains (Chondrichthyes) from the Paraná Basin, southern Brazil.

    PubMed

    Richter, Martha; Bosetti, Elvio P; Horodyski, Rodrigo S

    2017-01-01

    We report on the pioneering discovery of Devonian fish remains in the Paraná Basin, which represents the southernmost record of fishes from that period in mainland South America. The material comes from an outcrop at the lower portion of the São Domingos Formation, within Sequence C of the Paraná-Apucarana sub-basin in Tibagi, State of Paraná. Marine invertebrates are abundant in the same strata. The dark colored fish remains were collected in situ and represent natural moulds of partially articulated shark fin rays (radials). No elements such as teeth or prismatic cartilage have been preserved with the fins rays. This can be attributed to the dissolution of calcium-phosphatic minerals at the early stages of fossilization due to diagenetic processes possibly linked to strong negative taphonomic bias. This may have contributed to the fact that fishes remained elusive in the Devonian strata of this basin, despite substantial geological work done in the Paraná State in recent decades. In addition, the scarcity of fish fossils may be explained by the fact that the Devonian rock deposits in this basin originated in a vertebrate impoverished, cold marine environment of the Malvinokaffric Realm, as previously suspected.

  13. Paleogeography and depositional history of the Middle and Upper Devonian in central Idaho

    SciTech Connect

    Wiler, S.W.; Isaacson, P.E. )

    1991-02-01

    Middle and Upper Devonian rocks of central Idaho were deposited in a foreland basin east of the Antler orogenic welt' and west of a positive feature that extends along the central Idaho-Montana border. Upper Devonian rocks are anomalously thick (more than 700 m) in central Idaho, relative to the carbonate platform (300 m) in southwestern Montana. West of the Antler orogenic welt' Lower to Upper Devonian siliciclastic and carbonate rocks of the western Milligan Formation were deposited in an inner arc basin. East of the Antler orogenic welt' intertidal to subtidal deposition of the lower black dolomite unit of the Jefferson Formation occurred from Givetian to late Frasnian time. Restricted conditions suggest the Antler orogenic welt' was periodically an effective barrier to circulation as early as Givetian time. Stratigraphic variation in the upper Jefferson Formation is associated with subaerial exposure along the Antler orogenic welt' and increased foreland basin subsidence during the late Frasnian. Shallowing to supratidal and intertidal, siliciclastic channels and eolian sand probably are derived from early Paleozoic rocks along the Antler orogenic welt.' Conformably overlying the Jefferson Formation is the Famennian Trident Member of the Three Forks Formation, which contains a garnet-bearing argillaceous limestone, suggesting that erosion along the Antler orogenic welt' had reached Precambrian basement rocks. Middle Famennian flysch deposition suggests increased subsidence in the foreland prior to the unconformity over which Early Mississippian rocks were deposited.

  14. Paleogeographic setting of the Late Devonian to Early Mississippian Antler foreland, eastern Nevada and western Utah

    SciTech Connect

    Goebel, K.A. )

    1991-02-01

    Late Devonian through Early Mississippian depositional patterns in eastern Nevada and western Utah reflect transition from passive to collisional margin regimes. The Late Devonian (Frasnian) passive margin sequence (Devils Gate Limestone, Guilmette Limestone) was flexurally warped by thrust loading of the Roberts Mountains allochthon during eastward tectonic emplacement onto the continental margin. The foreland basin received minimal clastic input consisting primarily of bedded chert and hemipelagic claystone (Pine Cone Sequence, Woodruff Formation). Paleocurrent data from the northeast-southwest-trending back-bulge basin (Pilot basin) indicate that clastic detritus was derived from the forebulge to the north-northwest. The southern Pilot basin was the site of relatively shallow water carbonate deposition (West Range Limestone). During the Late Devonian (Famennian) and Early Mississippian (early Kinderhook), northern siliciclastic strata prograded over the southern carbonates, and the axis of the Pilot basin migrated eastward in conjunction with migration of the forebulge, foreland basin, and Antler thrust front. During the Early Mississippian (early Kinderhook), the forebulge migrated rapidly eastward through eastern Nevada and western Utah to produce local erosional surfaces of shoaling-upward sequences. The cratonward edge of the foreland basin was the site basin, west of the carbonate bank, shale and siltstone were deposited and grade westward into hemipelagic clay (Webb Formation). During the Early Mississippian (Osage), carbonate turbidites (Tripon Pass Limestone) derived from eroded highlands to the east in Utah and to the southeast in southern Nevada were deposited in the foreland trough.

  15. Rise of the Earliest Tetrapods: An Early Devonian Origin from Marine Environment

    PubMed Central

    George, David; Blieck, Alain

    2011-01-01

    Tetrapod fossil tracks are known from the Middle Devonian (Eifelian at ca. 397 million years ago - MYA), and their earliest bony remains from the Upper Devonian (Frasnian at 375–385 MYA). Tetrapods are now generally considered to have colonized land during the Carboniferous (i.e., after 359 MYA), which is considered to be one of the major events in the history of life. Our analysis on tetrapod evolution was performed using molecular data consisting of 13 proteins from 17 species and different paleontological data. The analysis on the molecular data was performed with the program TreeSAAP and the results were analyzed to see if they had implications on the paleontological data collected. The results have shown that tetrapods evolved from marine environments during times of higher oxygen levels. The change in environmental conditions played a major role in their evolution. According to our analysis this evolution occurred at about 397–416 MYA during the Early Devonian unlike previously thought. This idea is supported by various environmental factors such as sea levels and oxygen rate, and biotic factors such as biodiversity of arthropods and coral reefs. The molecular data also strongly supports lungfish as tetrapod's closest living relative. PMID:21779385

  16. Rift-related Devonian sedimentation and basin development in South China

    NASA Astrophysics Data System (ADS)

    Xun, Zhao; Allen, Mark B.; Whitham, Andrew G.; Price, Simon P.

    During Devonian times South China lay to the north of the Palaeo-Tethyan ocean, the boundary being a passive continental margin. A shallow sea covered the southern parts of the continent while northern areas, forming the Huanan Landmass, were emergent. At the beginning of the Devonian most of South China was above sea level. Subsequent transgression from the south gave rise to an irregular coastline with the development of many fault-controlled gulfs. Further transgression led to the development of an epicontinental sea with reefs forming along the margins of the submerged gulfs and black shales deposited within them. By Emsian time a widespread carbonate platform was established, while anoxic deposition continued in the troughs. The marine transgression peaked in the Frasnian Stage. During Famennian time widespread regression occurred and much of South China became once more emergent. Peneplanation of the Huanan Landmass led to the partial infilling of many of the older fault-bounded depressions. Throughout the Devonian the local distribution of sediments was strongly controlled by NE-SW trending transtensional faults that bounded NW-SE trending normal faults. These structures continued to influence sedimentation in the Late Palaeozoic, the Mesozoic and possibly the Tertiary in the offshore Beibu Gulf Basin.

  17. Shelf to basin transition of Silurian-Devonian rocks, Porcupine River area, east-central Alaska

    SciTech Connect

    Colean, D.A.

    1985-04-01

    Exposures of Silurian to lowermost Devonian strata in the Porcupine River region consist of an unnamed carbonate unit and the Road River Formation. Petrographic studies indicate that these rocks display facies representative of five depositional environments: basin, open sea shelf, deep shelf margin, open platform, and restricted shelf. The unnamed carbonate unit, exposed in the Linear Ridge area, is 390 ft (126 m) thick and records a history of restricted shelf to basinal sedimentation. Stratigraphic relations and paleontological studies suggest a Middle to Late Silurian (Ludlovian) age for this unit. The Road River Formation is Late Silurian (Ludlovian) to Early Devonian (Lochkovian) in age and is exposed near the confluence of the Porcupine-Salmontrout Rivers and downstream along the Lower Ramparts. It consists of 30-190 ft (10-61 m) of graptolitic shale with interbeds of siliceous limestone. Petrographic studies of the shales are interpreted to reflect deposition in a basinal setting, whereas the siliceous limestones represent deep shelf-margin debris flows derived from nearby, coeval shallow-water shelf environments. Together, the unnamed carbonate unit and the Road River Formation represent a shelf to basin transition on a carbonate ramp that transcends the Silurian-Devonian boundary. Petrographic examination of these rocks reveals that they are susceptible to a wide range of diagenetic processes, including (1) micritition, (2) neomorphism, (3) syntaxial overgrowths, (4) pressure solution (stylolitization), (5) trapping of dried hydrocarbons, (6) tensional stress (calcite veining), and (7) silicification.

  18. Acritarchs from Ponta Grossa Formation and their stratigraphic significance: Devonian of Parana basin

    SciTech Connect

    Dino, R.

    1983-03-01

    The Devonian fossil record in the Parana basin of Brazil is restricted to the Ponta Grossa Formation, a potential source rock unit. Paleontological studies of the macrofauna from this formation indicated an Early Devonian age. For this paper a wide range of surface samples and core samples from eight wells drilled by Pauliperto (a CESP-IPT joint venture) have been studied. Microplankton from the Devonian of the Parana basin never before described are presented here, together with their biostratigraphical and paleoecological implications. Intrabasinal and interbasinal correlations are also made. From a total of 60 species identified until now, twenty forms having well-defined stratigraphic ranges and broad (intercontinental) geographic representation are described herein. This assemblage is marked by the presence and diversity of the Subgroups Polygonomorphitae and Pteromorphitae. The Subgroup Acanthomorphitae is also well represented. The Emsian-Frasnian age previously established for the Ponta Grossa Formation through other palynological studies is further confirmed by the paleomicroplankton evidence. Moreover, the chronostratigraphic limits of these sediments may now be refined even further. Thus, depsite the presence of long-ranging forms, other species, such as Triangulina alargada, which is restricted to the Emsian in the La Vid Formation in northern Spain, allow a better chronostratigraphic subdivision of the Ponta Grossa Formation. The abundance of forms of Tasmanites together with a large quantity and diversity of microplankton provides the basis for the paleoecologic interpretations.

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

    USGS Publications Warehouse

    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.

  20. Causes of the great mass extinction of marine organisms in the Late Devonian

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2016-11-01

    The second of the five great mass extinctions of the Phanerozoic occurred in the Late Devonian. The number of species decreased by 70-82%. Major crises occurred at the Frasnian-Famennian and Devonian-Carboniferous boundary. The lithological and geochemical compositions of sediments, volcanic deposits, impactites, carbon and oxygen isotope ratios, evidence of climate variability, and sea level changes reflect the processes that led the critical conditions. Critical intervals are marked by layers of black shales, which were deposited in euxinic or anoxic environments. These conditions were the main direct causes of the extinctions. The Late Devonian mass extinction was determined by a combination of impact events and extensive volcanism. They produced similar effects: emissions of harmful chemical compounds and aerosols to cause greenhouse warming; darkening of the atmosphere, which prevented photosynthesis; and stagnation of oceans and development of anoxia. Food chains collapsed and biological productivity decreased. As a result, all vital processes were disturbed and a large portion of the biota became extinct.

  1. Further study of Late Devonian seed plant Cosmosperma polyloba: its reconstruction and evolutionary significance.

    PubMed

    Liu, Le; Wang, Deming; Meng, Meicen; Xue, Jinzhuang

    2017-06-26

    The earliest seed plants in the Late Devonian (Famennian) are abundant and well known. However, most of them lack information regarding the frond system and reconstruction. Cosmosperma polyloba represents the first Devonian ovule in China and East Asia, and its cupules, isolated synangiate pollen organs and pinnules have been studied in the preceding years. New fossils of Cosmosperma were obtained from the type locality, i.e. the Leigutai Member of the Wutong Formation in Fanwan Village, Changxing County, Zhejiang Province, South China. The collection illustrates stems and fronds extensively covered in prickles, as well as fertile portions including uniovulate cupules and anisotomous branches bearing synangiate pollen organs. The stems are unbranched and bear fronds helically. Fronds are dimorphic, displaying bifurcate and trifurcate types, with the latter possibly connected to fertile rachises terminated by pollen organs. Tertiary and quaternary rachises possessing pinnules are arranged alternately (pinnately). The cupule is uniovulate and the ovule has four linear integumentary lobes fused in basal 1/3. The striations on the stems and rachises may indicate a Sparganum-type cortex. Cosmosperma further demonstrates diversification of frond branching patterns in the earliest seed plants. The less-fused cupule and integument of this plant are considered primitive among Devonian spermatophytes with uniovulate cupules. We tentatively reconstructed Cosmosperma with an upright, semi-self-supporting habit, and the prickles along stems and frond rachises were interpreted as characteristics facilitating supporting rather than defensive structures.

  2. Abrupt ocean anoxia and mass extinction at the Hangenberg crisis, Devonian-Carboniferous boundary

    NASA Astrophysics Data System (ADS)

    Schmitz, M. D.; Davydov, V. I.

    2012-12-01

    The late Devonian period hosts a set of profound biotic crises accompanying episodes of tropical ocean anoxia, positive carbon isotope excursions, relative sea level rise and fall, and apparent global climatic cooling. The Hangenberg event, at the close of the Devonian, is the last of these crises which ushered in a new and long-lived icehouse climate regime spanning the Carboniferous and early Permian. New high-precision U-Pb zircon ages for bracketing volcanic tuffs constrain the timing and tempo of the Hangenberg biotic crisis. When combined with quantitative biostratigraphic analysis, these data constrain the duration of tropical ocean anoxia, mass extinction and carbon cycle perturbation to less than 100 thousand years. This rapidity and duration is consistent with a model of orbitally-forced cooling resulting in enhancement of oceanic circulation, in turn promoting catastrophic overturn, upwelling of anoxic bottom waters onto the tropical continental shelves, and consequent biotic reorganization. Enhanced organic carbon burial evidenced by a positive carbon isotope spike is also revealed as rapid and short-lived, but sufficient to draw down atmospheric CO2 and initiate a glacial pulse restricted to a single short period eccentricity cycle at the end-Devonian.

  3. A late Devonian impact event and its association with a possible extinction event on Eastern Gondwana

    NASA Technical Reports Server (NTRS)

    Wang, K.; Geldsetzer, H. H. J.

    1992-01-01

    Evidence from South China and Western Australia for a 365-Ma impact event in the Lower crepida conodont zone of the Famennian stage of the Late Devonian (about 1.5 Ma after the Frasnian/Famennian extinction event) includes microtektitelike glassy microspherules, geochemical anomalies (including a weak Ir), a probable impact crater (greater than 70 k) at Taihu in South China, and an Ir anomaly in Western Australia. A brachiopod faunal turnover in South China, and the 'strangelove ocean'-like c-delta 13 excursions in both Chinese and Australian sections indicate that at least a regional-scale extinction might have occurred at the time of the impact. A paleoreconstruction shows that South China was very close to and facing Western Australia in the Late Devonian. The carbon isotopic excursions, which occur at the same stratigraphic level in both South China and Western Australia cannot be explained as being coincidental. The c-delta 13 excursions and the brachiopod faunal turnover in South China indicate that there might have been at least a regional (possibly global) extinction in the Lower crepida zone. The impact-derived microspherules and geochemical anomalies (especially the Ir) indicate a Lower crepida zone impact event on eastern Gondwana. The location, type of target rocks, and possibly age of the Taihu Lake crater qualify as the probable site of this Late Devonian impact.

  4. Geologic description of middle Devonian Chert Reservoir, Block 31 field, Crane County, Texas

    SciTech Connect

    Ebanks, W.J. Jr.

    1988-01-01

    Block 31 field is a large anticlinal structure that produces from six pay zones. The first miscible gas-injection enhanced oil recovery project has been operated by ARCO since 1952 in the middle Devonian reservoir, which is the main producing interval in the field. The middle Devonian unit was deposited as a siliceous, calcareous ooze in a basin-slope environment in the ancient Tobosa basin. Sedimentation buried earlier fault blocks, as the slope deposits aggraded and prograded mainly from the west and south. Subsequent diagenesis converted the ooze into calcareous chert. Reservoir quality of the chert depends on degree of compaction and quartz cementation. Gray, dense, glassy chert at the base of the sequence is nonporous except for small, incipient fractures in the brittle matrix. Creamy white, evenly laminated, microporous, calcareous chert, which alternates with and overlies the dense chert in the lower half of the middle Devonian interval, has porosity of 10-30% and permeability as great as 10 md. The upper half of the reservoir interval consists mainly of light-gray and white, partially porous, heterogeneous, calcareous chert. This rock type has porosity of 5-20%, but permeability is usually less than 3 md. Patchy silica cement, discontinuous low-permeability laminae, and thin beds of dense limestone reduce its effectiveness as a reservoir.

  5. Stratigraphic evidence for Devonian tectonism on lineaments at Allegheny Front, West Virginia; supporting material

    USGS Publications Warehouse

    Wheeler, R.L.

    1983-01-01

    At the Allegheny Front in northeastern West Virginia, five large structural lineaments trend northwesterly to westerly across the structural grain. This paper concludes that two and perhaps three of them separated structures that were active in Devonian time. Along strike over about 200 km of the Front, J. M. Dennison and coworkers recognized and mapped numerous, mostly thin, shale, siltstone, sandstone, and limestone units in 18 measured sections between the Early Devonian Oriskany Sandstone and the Late Devonian Hampshire Formation. Many of these units terminate in intervals between measured sections. Nonparametric statistical analysis reveals that significant numbers of stratigraphic terminations occur in and between intervals in which three of the five lineaments intersect the Front. The Petersburg and Fairmont-Rowlesburg and perhaps the Bartow lineaments were loci of structural control over topography, bathymetry, or both, and of structural influence on patterns of influx and dispersal of clastic sediment. It is not clear whether this pre-Alleghany activity reflects intermittent motion (1) on a strike-transverse basement fault, as occurred under similar lineaments in Pennsylvania and Alabama, or (2) between Paleozoic thrust masses advancing somewhat independently of each other. However, if the Petersburg lineament formed over a basement fault, it cannot still overlie it because the rocks containing the lineament have been detached and transported too far to the northwest. Of the five lineaments considered, the one most likely to have formed over and to still overlie a basement fault is the Parsons lineament, especially in its northwestern portion in the eastern Plateau province.

  6. Lung Transplantation

    MedlinePlus

    ... who have severe COPD Cystic fibrosis Idiopathic pulmonary fibrosis Alpha-1 antitrypsin deficiency Pulmonary hypertension Complications of lung transplantation include rejection of the transplanted lung and infection. NIH: National Heart, Lung, and Blood Institute

  7. Lung disease

    MedlinePlus

    ... the lungs to take in oxygen and release carbon dioxide. People with this type of lung disorder often ... the lungs to take up oxygen and release carbon dioxide. These diseases may also affect heart function. An ...

  8. Collapsed Lung

    MedlinePlus

    A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a ... is called pneumothorax. If only part of the lung is affected, it is called atelectasis. Causes of ...

  9. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Sullivan, Sharon G.; Ink, Gary; Grabois, Andrew; Barr, Catherine

    2001-01-01

    Includes six articles that discuss research and statistics relating to the book trade. Topics include prices of U.S. and foreign materials; book title output and average prices; book sales statistics; book exports and imports; book outlets in the U.S. and Canada; and books and other media reviewed. (LRW)

  10. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Lofquist, William S.

    1998-01-01

    Provides data on prices of U.S. and foreign materials; book title output and average prices, 1996 final and 1997 preliminary figures; book sales statistics, 1997--AAP preliminary estimates; U.S. trade in books, 1997; international book title output, 1990-95; book review media statistics; and number of book outlets in the U.S. and Canada. (PEN)

  11. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Sullivan, Sharon G.; Ink, Gary; Grabois, Andrew; Barr, Catherine

    2001-01-01

    Includes six articles that discuss research and statistics relating to the book trade. Topics include prices of U.S. and foreign materials; book title output and average prices; book sales statistics; book exports and imports; book outlets in the U.S. and Canada; and books and other media reviewed. (LRW)

  12. The Rhynie hot-spring system: implications for the Devonian timescale, development of Devonian biota, gold mineralization, evolution of the atmosphere and Earth outgassing

    NASA Astrophysics Data System (ADS)

    Mark, D.; Rice, C.; Stuart, F.; Trewin, N.

    2011-12-01

    The Rhynie cherts are hot spring sinters that contain world-renowned plant and animal remains and anomalously high quantities of heavy metals, including gold. The biota in several beds is preserved undeformed with plants in life positions thus establishing that they and the indurating hydrothermal fluids were coeval. Despite the international importance of the Rhynie cherts their age has been poorly constrained for three reasons: (1) lack of a precise radio-isotopic age, (2) low resolution of spore biostratigraphic schemes for Devonian terrestrial deposits, with only one to a few zones per stage, and (3) poor resolution of the early Devonian timescale. Wellman (2004) assigned a Pragian-?earliest Emsian age to the Rhynie cherts on the basis of the spore assemblage. An 40Ar/39Ar dating study targeting Rhynie chert yielded an age of 395 ± 12 Ma (1σ) (Rice et al., 1995). This contribution discusses a new high-precision 40Ar/39Ar age (407.1 ± 2.2 Ma, 2σ) for the Devonian hot-spring system at Rhynie (Mark et al., 2011) and demonstrates that a proposed U-Pb age (411.5 ± 1.1 Ma, 2σ) for the Rhynie cherts (Parry et al., 2011) is inconsistent with both field evidence and our interpretation of the U-Pb data. The 40Ar/39Ar age provides a robust marker for the polygonalis-emsiensis Spore Assemblage Biozone within the Pragian-?earliest Emsian. It also constrains the age of a wealth of flora and fauna preserved in life positions as well as dating gold mineralization. Furthermore, we have now determined the Ar isotope composition of pristine samples of the Rhynie chert using an ARGUS multi-collector mass spectrometer and a low blank laser extraction technique. 40Ar/36Ar are systematically lower than the modern air value (Lee et al., 2006), and are not accompanied by non-atmospheric 38Ar/36Ar ratios. We conclude that the Rhynie chert captured and has preserved Devonian atmosphere-derived Ar. The data indicate that the 40Ar/36Ar of Devonian atmosphere was at least 3 % lower

  13. Lung cancer: Current status and prospects for the future

    SciTech Connect

    Mountain, C.F.; Carr, D.T.

    1986-01-01

    This book contains 32 papers. Some of the titles are: Activation of cellular ras genes in human neoplasms; The valve of definitive radiation therapy of unresectable squamous cell carcinoma, large cell carcinoma, and adenocarcinoma of the lung; Current concepts of chemotherapy and radiotherapy for small cell lung cancer, and Current status of immunotherapy for lung cancer.

  14. The impact of astronomical forcing on the Late Devonian greenhouse climate

    NASA Astrophysics Data System (ADS)

    De Vleeschouwer, David; Crucifix, Michel; Bounceur, Nabila; Claeys, Philippe

    2014-09-01

    The geological record of the Paleozoic often exhibits cyclic features, in many cases the result of changes in paleoclimate. However, a thorough understanding of the processes that were driving Paleozoic climate change has not yet been reached. The main reason is relatively poor time-control on Paleozoic paleoclimate proxy records. This problem can be overcome by the identification of cyclic features resulting from astronomical climate forcing in the stratigraphic record. To correctly identify these cyclic features, it is necessary to quantify the effects of astronomical climate forcing under conditions different from today. In this work, we apply Late Devonian (375 Ma) boundary conditions to the Hadley Centre general circulation model (HadSM3). We estimate the response of Late Devonian climate to astronomical forcing by keeping all other forcing factors (e.g. paleogeography, pCO2, vegetation distribution) fixed. Thirty-one different "snapshots" of Late Devonian climate are simulated, by running the model with different combinations of eccentricity (e), obliquity (ε) and precession (ω˜). From the comparison of these 31 simulations, it appears that feedback mechanisms play an important role in the conversion of astronomically driven insolation variations into climate change, such as the formation of sea-ice and the development of an extensive snow cover on Gondwana. We compare the "median orbit" simulation to lithic indicators of paleoclimate to evaluate whether or not HadSM3 validly simulates Late Devonian climates. This comparison suggests that the model correctly locates the major climate zones. This study also tests the proposed link between the formation of ocean anoxia and high eccentricity (De Vleeschouwer et al., 2013) by comparing the δ18Ocarb record of the Frasnian-Famennian boundary interval from the Kowala section (Poland) with a simulated time series of astronomically forced changes in mean annual temperature at the paleolocation of Poland. The

  15. Palaeomagnetic and rock magnetic study of Lower Devonian sediments from Podolia, SW Ukraine: remagnetization problems

    NASA Astrophysics Data System (ADS)

    Jeleńska, M.; Kądziałko-Hofmokl, M.; Bakhmutov, V.; Poliachenko, I.; Ziółkowski, P.

    2015-01-01

    The Early Devonian segment of the Apparent Polar Wander Path (APWP) for Baltica was defined by seven poles almost all from British Islands. Among them only one was obtained for Devonian sediments from Ukraine. The lack of data from other parts of Baltica than Britain makes this segment of the path dubious. To improve this situation we carried out palaeomagnetic study of the Devonian sedimentary sequence in Podolia (Ukraine). The studied rocks represent grey limestone and red beds and were sampled in seven outcrops in the basin of the Dniester River. The standard palaeomagnetic experiments reveal Permian remagnetization corresponding to the pole position: 47°S/351.5°E for red beds and 45°S/340°E for grey limestone. The second component corresponding to the nearly Devonian pole position (2.3°S/338.4°E for red beds and 0°S/329°E for grey limestone) was determined as primary based on the fact that they were recognized in different sediments-limestone and sandstone and carried by different magnetic minerals: multidomain (MD) magnetite in grey limestone, and detritic grains composed of primary hematite with ilmenite intergrowths in red beds. The fabric of anisotropy of magnetic susceptibility of red sandstone and these samples of grey limestone which preserved Devonian magnetization are typical for sedimentary structure. The preservation of primary component of natural remanence was supported by analysis of mechanism of remagnetization and acquisition of secondary components. Hysteresis properties indicate that red beds underwent chemical remagnetization whereas grey limestone were not altered. Variscan orogeny caused the elevated heat and fluid flows along the edge of the Trans European Suture Zone and deep burial of Podolia. We suppose that red beds underwent chemical remagnetization caused by fluid flows, whereas grey limestone could acquire thermoviscous remanence due to elevated temperature caused by burial. Hot fluids could easily penetrate into sandstone

  16. Medical rare book provenance.

    PubMed Central

    Overmier, J A; Sentz, L

    1987-01-01

    Provenance is defined as the record of a book's ownership history. Its value and uses are explored. A survey of provenance practices in medical school rare book libraries found that only 21% of the reporting libraries maintain this important file. Examples of the uses and value of a provenance file in a medical rare book collection are presented. Decisions necessary to institute and maintain such a file are outlined and discussed. PMID:3828606

  17. Give a Book, Take a Book | Poster

    Cancer.gov

    Collection has begun for the 15th Annual Book & Media Swap sponsored by the Scientific Library. NCI at Frederick staff can use this opportunity to clear out personal book and DVD shelves of unwanted materials, donate them to the swap, and then receive “new” materials in return. The library staff will collect materials through Tuesday, Oct. 27. Kick-off day for the event is Wednesday, Oct. 28, 10 a.m. to 2 p.m., in the lobby of the Conference Center in Building 549.

  18. Give a Book, Take a Book | Poster

    Cancer.gov

    Collection has begun for the 15th Annual Book & Media Swap sponsored by the Scientific Library. NCI at Frederick staff can use this opportunity to clear out personal book and DVD shelves of unwanted materials, donate them to the swap, and then receive “new” materials in return. The library staff will collect materials through Tuesday, Oct. 27. Kick-off day for the event is Wednesday, Oct. 28, 10 a.m. to 2 p.m., in the lobby of the Conference Center in Building 549.

  19. Native American Children's Books. Book Reviews.

    ERIC Educational Resources Information Center

    Moulton, Kathryn Elizabeth; Cornelius, Carol

    1993-01-01

    Reviews 11 children's books, published 1990-93, suitable for elementary and middle school students, covering Native riddles; Hiawatha as founder of the Iroquois confederacy; Chief Seattle's famous speech; stories about Inuit life and Mexican village life during the 1500s; Sequoyah and the Cherokee alphabet; the Iroquois creation myth; Wampanoag…

  20. 2011 Renewable Energy Data Book (Book)

    SciTech Connect

    Gelman, R.

    2012-10-01

    This Renewable Energy Data Book for 2011 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar energy, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investments.

  1. 2012 Renewable Energy Data Book (Book)

    SciTech Connect

    Gelman, R.

    2013-10-01

    This Renewable Energy Data Book for 2012 provides facts and figures in a graphical format on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investment.

  2. 2010 Renewable Energy Data Book (Book)

    SciTech Connect

    Gelman, R.

    2011-10-01

    This Renewable Energy Data Book for 2010 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar energy, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investments.

  3. 2013 Renewable Energy Data Book (Book)

    SciTech Connect

    Esterly, S.

    2014-12-01

    This Renewable Energy Data Book for 2013 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investment.

  4. Native American Children's Books. Book Reviews.

    ERIC Educational Resources Information Center

    Moulton, Kathryn Elizabeth; Cornelius, Carol

    1993-01-01

    Reviews 11 children's books, published 1990-93, suitable for elementary and middle school students, covering Native riddles; Hiawatha as founder of the Iroquois confederacy; Chief Seattle's famous speech; stories about Inuit life and Mexican village life during the 1500s; Sequoyah and the Cherokee alphabet; the Iroquois creation myth; Wampanoag…

  5. ESL Literacy. Student Book; Teacher's Resource Book.

    ERIC Educational Resources Information Center

    Nishio, Yvonne Wong

    The student workbook and teacher manual for an adult English-as-a-Second-Language (ESL) literacy course are presented. It assumes that students have some native language literacy skills but may have had little or no prior schooling. The student book has 10 units, topically organized: alphabet; numbers; time; the calendar; money; school; the…

  6. Paradigm Lost. Book Review.

    ERIC Educational Resources Information Center

    Murphy, James M.

    1996-01-01

    Claiming to have developed a new conceptualization of creative phenomena, Howard Gardner has rounded up the usual biographical suspects in his new book "Creating Minds: An Anatomy of Creativity Seen Through the Lives of Freud, Einstein, Picasso, Stravinsky, Eliot, Graham, and Gandhi" (Basic Books, 1993). Gardner doesn't successfully…

  7. Books in Our Future.

    ERIC Educational Resources Information Center

    Boorstin, Daniel J.

    This study explores the changing role of the book in the future. The report draws on interviews with authors, publishers, booksellers, computer experts, librarians, scientists, educators, and scholars and on the experience of the Library of Congress staff. The first part, "The Culture of the Book: Today and Tomorrow," includes sections…

  8. Mass Digitization of Books

    ERIC Educational Resources Information Center

    Coyle, Karen

    2006-01-01

    Mass digitization of the bound volumes that we generally call "books" has begun, and, thanks to the interest in Google and all that it does, it is getting widespread media attention. The Open Content Alliance (OCA), a library initiative formed after Google announced its library book digitization project, has brought library digitization projects…

  9. Why Write Book Reviews?

    ERIC Educational Resources Information Center

    Obeng-Odoom, Franklin

    2014-01-01

    The pressure to publish or perish or, more recently, to be visible or vanish, marginalises a culture of critical reading and reflection that has historically been the province of book reviews. Today, book reviews are roundly rejected by academic bureaucrats as unimportant, easy to write and hence, easy to get published, mere summaries, uncritical…

  10. Books under Fire

    ERIC Educational Resources Information Center

    Durbin, Kathie

    2005-01-01

    Notwithstanding the First Amendment, book banning is a practice rooted in American history. In 1873, Congress passed the Comstock Law in an effort to legislate public morality. Though rarely enforced, the act remains on the books. A survey by the National School Boards Association found that one-third of challenges to school reading materials in…

  11. Why Books Will Survive.

    ERIC Educational Resources Information Center

    Jennings, Lane

    1983-01-01

    High prices, paper that self destructs, and competition from computers and video forms may mean hard times ahead for books. The factor most likely to assure the survival of books into the future is that there is simply no experience in life that matches silent reading. (Author/RM)

  12. Timber Management Field Book

    Treesearch

    USDA Forest Service, Northeastern Area, State and Private Forestry

    2005-01-01

    The Timber Management Field Book has been in use since the late 1960's and is a popular field tool for foresters to accomplish field work. It is used to access information on timber volumes, site indexes, surveying and cruising data, reforestation, scaling, and other silvicultural information while in the field. The new field book revises and supersedes NA-MR-7...

  13. Celebrating Censored Books.

    ERIC Educational Resources Information Center

    Karolides, Nicholas J., Ed.; Burress, Lee, Ed.

    Intended to provide rationales for the use of a group of controversial books in American public schools, this manual explains the educational values of 33 of the most frequently challenged books. Detailed rationales include such information as historical perspective, literary elements, pertinence, and thematic content. Some of the titles include…

  14. The Obama Books Boom

    ERIC Educational Resources Information Center

    Roach, Ronald

    2009-01-01

    As Barack Obama's rise to power inspires a flood of books, scholars hope the publishing trend will yield serious analysis. Barack Obama's rise from Illinois politics to the U.S. presidency has inspired authors to produce a flood of books chronicling the 44th commander in chief's life story and political career. Obama's political odyssey invites…

  15. Special Book Review Issue.

    ERIC Educational Resources Information Center

    Grauer, Barbara Ellman, Ed.; And Others

    1999-01-01

    Offers reviews of 40 new and classic books for career counselors and career centers. Includes reviews of books on the following topics: assessment, career management, distance learning, entrepreneurship, the spirit-work connection, job-search methods, lifelong career development, as well as guides and workbooks. (JOW)

  16. Special Issue: Book Reviews.

    ERIC Educational Resources Information Center

    Kohs, Perla, Ed.

    1992-01-01

    Reviews of 42 books in the following categories are provided: career counseling theory and skills, organizational development, career and life planning, adult career development, retirement, career fields, job search, job success, entrepreneurship, college and women, college and the military, life management, creativity, and reference books. (SK)

  17. Amazing Altered Books

    ERIC Educational Resources Information Center

    Kieling, Linda W.

    2006-01-01

    Linda Kieling, an art teacher at Rosemont Ridge Middle school in West Linn, Oregon, describes an altered book art project she introduced to her students. Alteration of books is a form of recycling that started in the eleventh century when Italian monks recycled old manuscripts written on vellum by scraping off the ink and adding new text and…

  18. The Book Club Exploded

    ERIC Educational Resources Information Center

    Hoffert, Barbara

    2006-01-01

    One leader, 12 readers, and a few well-thumbed copies of Jane Austen's "Pride and Prejudice." That is all a book club once required, but this is no longer the case. This article describes how the runaway popularity of book clubs has brought with it a whole new set of possibilities. Thematic discussion? A fiction/nonfiction mix? Videoconferencing?…

  19. Books for Children.

    ERIC Educational Resources Information Center

    Hildebrand, Joan M.

    1993-01-01

    This annotated bibliography includes 27 children's books, 15 of which are fiction, and 12 nonfiction. Of the nonfiction books, three discuss historical topics and nine cover nature-related topics such as rainforests, the ocean floor, snakes and other animals, and rural farm life. (SM)

  20. Do Books Still Matter?

    ERIC Educational Resources Information Center

    Aronson, Marc

    2007-01-01

    Welcome to the 21st century, where many students turn to Google as their main source of information. In fact, some kids wouldn't look anywhere else but the Internet. So what does that mean for nonfiction books? Five years ago, everybody warned that fresh, interactive digital content would eventually replace old-fashioned books. However, last…

  1. The Obama Books Boom

    ERIC Educational Resources Information Center

    Roach, Ronald

    2009-01-01

    As Barack Obama's rise to power inspires a flood of books, scholars hope the publishing trend will yield serious analysis. Barack Obama's rise from Illinois politics to the U.S. presidency has inspired authors to produce a flood of books chronicling the 44th commander in chief's life story and political career. Obama's political odyssey invites…

  2. Astronomy Books of 1985.

    ERIC Educational Resources Information Center

    Mercury, 1986

    1986-01-01

    Provides annotated listing of books in 16 areas: (1) amateur astromony; (2) children's books; (3) comets; (4) cosmology; (5) education in astronomy; (6) general astronomy; (7) history of astronomy; (8) life in the universe; (9) miscellaneous; (10) physics and astronomy; (11) pseudo-science; (12) space exploration; (13) stars and stellar evolution;…

  3. Astronomy Books of 1985.

    ERIC Educational Resources Information Center

    Mercury, 1986

    1986-01-01

    Provides annotated listing of books in 16 areas: (1) amateur astromony; (2) children's books; (3) comets; (4) cosmology; (5) education in astronomy; (6) general astronomy; (7) history of astronomy; (8) life in the universe; (9) miscellaneous; (10) physics and astronomy; (11) pseudo-science; (12) space exploration; (13) stars and stellar evolution;…

  4. Books in the Family.

    ERIC Educational Resources Information Center

    Swinger, Alice K.

    1989-01-01

    Opportunities for parents to encourage reading in the family are noted and ways to enhance the reading experience are discussed, including writing letters to book characters, singing combined with reading aloud, supplementing school subjects with enjoyable reading, sharing books at family gatherings, and using family experiences for book…

  5. Pictures into Books

    ERIC Educational Resources Information Center

    Adams, Linda; Lehman, Linda

    2007-01-01

    In this article, the authors describe a project that integrated computer technology skills with art history, photography, and layout/design. Approximately 160 fourth graders became photographers and created books on the following concepts: position words, numbers, colors, alphabet, shapes, and patterns. The books were professionally bound and…

  6. Book Processing Facility Design.

    ERIC Educational Resources Information Center

    Sheahan (Drake)-Stewart Dougall, Marketing and Physical Distribution Consultants, New York, NY.

    The Association of New York Libraries for Technical Services (ANYLTS) is established to develop and run a centralized book processing facility for the public library systems in New York State. ANYLTS plans to receive book orders from the 22 library systems, transmit orders to publishers, receive the volumes from the publishers, print and attach…

  7. Children's Books in India.

    ERIC Educational Resources Information Center

    Rao, Mohini

    This report, given at a special meeting held in Tehran, discusses the creation and publication of children's books in India, most of which came into being only after India achieved independence. Now both private publishers and government agencies supplement one another in publishing various types of books--fiction, science, biography, adventure,…

  8. Children's Books in Finland.

    ERIC Educational Resources Information Center

    Kuivasmaki, Riitta

    1984-01-01

    Discusses influence of Finnish Institute for Children's Literature (SNI) on writing, illustrating, translating, and marketing of children's books in Finland, and notes efforts of Finnish Section of International Board on Books for Young People to make children's literature and connected research better known to public. Publications of SNI are…

  9. Physics books crossword

    NASA Astrophysics Data System (ADS)

    2009-12-01

    It is time once again for the Physics World Christmas books crossword, with a puzzle and clues compiled by Peter Wade-Wright. The answers are all physics or science related, and 10 of them come from titles of books reviewed in these pages in 2009. There is no prize except the satisfaction of completion and the solution is given on page 43.

  10. Physics books crossword

    NASA Astrophysics Data System (ADS)

    2008-12-01

    The Physics World Christmas books crossword is here again with a new puzzle and cryptic clues compiled by Peter Wade-Wright. The answers are all physics or science related, and seven of them come from titles of books reviewed in these pages in 2008. There is no prize except the satisfaction of completion and the solution is given on page 49.

  11. Strawberry Square. Song Book.

    ERIC Educational Resources Information Center

    Larson, Tom

    Designed to accompany a series of 33 television programs in music education for kindergarten and first grade children, this song book (containing sheet music) correlates with activities in the teacher's guide. Titles of songs included in the book are: Let a Song Tell a Story (short and long versions); If I Had a Hammer; A Happy Street; Let the…

  12. Hints on Sharing Books.

    ERIC Educational Resources Information Center

    Dorsey, Mary E., Comp.; Horne, Ulysses G., Comp.

    Based on the realization that each child must be given the opportunity to develop as a unique individual and that exposure to books expands a child's world, stimulating his creative thinking and his desire for new experiences, this booklet presents in outline form a variety of suggestions for encouraging children to share the books they have read.…

  13. Death, Children, and Books.

    ERIC Educational Resources Information Center

    Carr, Robin L.

    The books listed in this annotated bibliography are intended to help children understand the reality of death and deal with the mystery and emotions that accompany it. Each entry indicates the genre and reading level of the book and provides a brief description of the attitude toward death that it conveys. The selections include fables, fantasy,…

  14. More2books

    ERIC Educational Resources Information Center

    Australian Mathematics Teacher, 2012

    2012-01-01

    Reach for the Stars is AAMT's data-collection activity for National Literacy and Numeracy Week, funded by the Australian Government. This year's activity was on the theme "More2books" and many thousands of students and their teachers explored the mathematics of the books in their classrooms. This article presents a version of the…

  15. Books for Children.

    ERIC Educational Resources Information Center

    Hildebrand, Joan M.

    1993-01-01

    This annotated bibliography includes 27 children's books, 15 of which are fiction, and 12 nonfiction. Of the nonfiction books, three discuss historical topics and nine cover nature-related topics such as rainforests, the ocean floor, snakes and other animals, and rural farm life. (SM)

  16. More than Comic Books

    ERIC Educational Resources Information Center

    Boerman-Cornell, Bill

    2013-01-01

    Graphic novels (book-length fiction or nonfiction narratives told using the conventions of a comic book) bring together text and image in a way that seems to capture students' imaginations. Right now, there is little more than anecdotal research about how graphic novels can be used within specific middle school and high school disciplines. As…

  17. Test Scoring [book review].

    ERIC Educational Resources Information Center

    Meijer, Rob R.

    2003-01-01

    This book discusses how to obtain test scores and, in particular, how to obtain test scores from tests that consist of a combination of multiple choice and open-ended questions. The strength of the book is that scoring solutions are presented for a diversity of real world scoring problems. (SLD)

  18. Test Scoring [book review].

    ERIC Educational Resources Information Center

    Meijer, Rob R.

    2003-01-01

    This book discusses how to obtain test scores and, in particular, how to obtain test scores from tests that consist of a combination of multiple choice and open-ended questions. The strength of the book is that scoring solutions are presented for a diversity of real world scoring problems. (SLD)

  19. Open Books, Open Minds.

    ERIC Educational Resources Information Center

    McMath, Joan; King, Margaret

    1993-01-01

    Describes using picture books and science activities in early childhood science instruction. Suggests titles of books and activities for the following topics: Time for Pets; Environmental Awareness; Dinosaurs Galore; Nighttime Science; Simple Machines; Insect Collections; Snowy Days; Water, Water, Everywhere; and Experimental Activities. (PR)

  20. Strawberry Square. Song Book.

    ERIC Educational Resources Information Center

    Larson, Tom

    Designed to accompany a series of 33 television programs in music education for kindergarten and first grade children, this song book (containing sheet music) correlates with activities in the teacher's guide. Titles of songs included in the book are: Let a Song Tell a Story (short and long versions); If I Had a Hammer; A Happy Street; Let the…

  1. Celebrating Censored Books.

    ERIC Educational Resources Information Center

    Karolides, Nicholas J., Ed.; Burress, Lee, Ed.

    Intended to provide rationales for the use of a group of controversial books in American public schools, this manual explains the educational values of 33 of the most frequently challenged books. Detailed rationales include such information as historical perspective, literary elements, pertinence, and thematic content. Some of the titles include…

  2. More2books

    ERIC Educational Resources Information Center

    Australian Mathematics Teacher, 2012

    2012-01-01

    Reach for the Stars is AAMT's data-collection activity for National Literacy and Numeracy Week, funded by the Australian Government. This year's activity was on the theme "More2books" and many thousands of students and their teachers explored the mathematics of the books in their classrooms. This article presents a version of the…

  3. Astronomy books in Spanish

    NASA Astrophysics Data System (ADS)

    Fierro, Julieta

    Great cultures have created language. They have discovered its strength among other reasons for education. For a long time the Bible was one of the few books available in western culture, its influence is beyond any doubt. Many developing nations have no science books in their mother tongue. They might carry a few translations but these do not convey the local culture so it is harder for students to grasp the concepts and to build on what they know. Books, even if they are extremely simple, should be written in local languages because that will facilitate the conveying of knowledge and the creation of scientific culture. In the books examples that pertain to every day local life must be given, in particular examples that have to do with women. Women play a central role in developing nations by child bearing; if they become literate they will influence enormously the quality of their children's education, in particular their science comprehension. In Mexico a collection that includes astronomy books has recently been edited by the National Council for Culture and Arts. The books are small and light, which encourages middle-school students to carry them around and read them while traveling in public transportation, such as the subway. Every other page is a new subject, that carries illustrations, abstracts and conclusions. The astronomy books are on search for extraterrestrial life, the stars and the universe. These books are distributed nation-wide and are inexpensive. They have been written by Mexican astronomers.

  4. Buy the Book

    ERIC Educational Resources Information Center

    Washington, Thomas

    2003-01-01

    The Follett library software system is the literary conscience of St. Francis High School. It reports on overdue books, checkout statistics, and online catalog search records. The circulation numbers tell that reading is a tough sell for today's teens. As the school's custodian of books and information, the author describes his efforts at leading…

  5. Whither the Great Books?

    ERIC Educational Resources Information Center

    Casement, William

    2002-01-01

    The decades since the 1960s have been unfortunate in many respects for American higher education, but things are not uniformly bleak. Here and there, the study of Great Books persists. The general picture that is available, then, of the health of great-books study in colleges today is mixed. High-visibility news stories, along with curriculum…

  6. Bell, Book and Candle.

    ERIC Educational Resources Information Center

    Eichenberg, Fritz

    1984-01-01

    This May Hill Arbuthnot Honor Lecture relates the career of an artist and illustrator of children's books whose best-known works for young children are "Dancing in the Moon" and "Ape in a Cape." School years, apprenticeship, first books, wood engravings, use of illustrations, and the generation gap are highlighted. (EJS)

  7. More than Comic Books

    ERIC Educational Resources Information Center

    Boerman-Cornell, Bill

    2013-01-01

    Graphic novels (book-length fiction or nonfiction narratives told using the conventions of a comic book) bring together text and image in a way that seems to capture students' imaginations. Right now, there is little more than anecdotal research about how graphic novels can be used within specific middle school and high school disciplines. As…

  8. Books Born Digital

    ERIC Educational Resources Information Center

    Eaton, Lance

    2009-01-01

    It used to be that a book was published first as a hardcover, then as a lower-cost paperback. With increasingly tech-savvy consumers demanding instantaneous access to content in various formats, that publishing protocol has in the last decade changed to one in which the book in codex form often remains the focus, but digital "extras"…

  9. Books Born Digital

    ERIC Educational Resources Information Center

    Eaton, Lance

    2009-01-01

    It used to be that a book was published first as a hardcover, then as a lower-cost paperback. With increasingly tech-savvy consumers demanding instantaneous access to content in various formats, that publishing protocol has in the last decade changed to one in which the book in codex form often remains the focus, but digital "extras"…

  10. Wordless Books: Picture Perfect

    ERIC Educational Resources Information Center

    Lukehart, Wendy

    2011-01-01

    Wordless books offer a bounty of riches. The format is accessible to everyone regardless of language or reading ability, making the books ideal for use in international settings, classes with nonnative speakers, or families with adults or children who are struggling or emergent readers. They enrich the aesthetic lives and literacy skills of…

  11. The Book Club Exploded

    ERIC Educational Resources Information Center

    Hoffert, Barbara

    2006-01-01

    One leader, 12 readers, and a few well-thumbed copies of Jane Austen's "Pride and Prejudice." That is all a book club once required, but this is no longer the case. This article describes how the runaway popularity of book clubs has brought with it a whole new set of possibilities. Thematic discussion? A fiction/nonfiction mix? Videoconferencing?…

  12. Special Book Review Issue.

    ERIC Educational Resources Information Center

    Grauer, Barbara Ellman, Ed.; And Others

    1999-01-01

    Offers reviews of 40 new and classic books for career counselors and career centers. Includes reviews of books on the following topics: assessment, career management, distance learning, entrepreneurship, the spirit-work connection, job-search methods, lifelong career development, as well as guides and workbooks. (JOW)

  13. Mass Digitization of Books

    ERIC Educational Resources Information Center

    Coyle, Karen

    2006-01-01

    Mass digitization of the bound volumes that we generally call "books" has begun, and, thanks to the interest in Google and all that it does, it is getting widespread media attention. The Open Content Alliance (OCA), a library initiative formed after Google announced its library book digitization project, has brought library digitization projects…

  14. China Connections Reference Book.

    ERIC Educational Resources Information Center

    Kalat, Marie B.; Hoermann, Elizabeth F.

    This reference book focuses on six aspects of the geography of the People's Republic of China. They are: territory, governing units, population and land use, waterways, land forms, and climates. Designed as a primary reference, the book explains how the Chinese people and their lifestyles are affected by China's geography. Special components…

  15. Wordless Books: Picture Perfect

    ERIC Educational Resources Information Center

    Lukehart, Wendy

    2011-01-01

    Wordless books offer a bounty of riches. The format is accessible to everyone regardless of language or reading ability, making the books ideal for use in international settings, classes with nonnative speakers, or families with adults or children who are struggling or emergent readers. They enrich the aesthetic lives and literacy skills of…

  16. Book of the Hopi.

    ERIC Educational Resources Information Center

    Waters, Frank

    Materials for the compilation of this book were acquired from Hopi spokesmen (30 elders of the Hopi Indian tribe in northern Arizona) who regarded it as a monumental record that would give their descendants a complete history of their people and their religious beliefs. It was also desired that the 4-part book serve the practical purpose of…

  17. Death, Children, and Books.

    ERIC Educational Resources Information Center

    Carr, Robin L.

    The books listed in this annotated bibliography are intended to help children understand the reality of death and deal with the mystery and emotions that accompany it. Each entry indicates the genre and reading level of the book and provides a brief description of the attitude toward death that it conveys. The selections include fables, fantasy,…

  18. Do Books Still Matter?

    ERIC Educational Resources Information Center

    Aronson, Marc

    2007-01-01

    Welcome to the 21st century, where many students turn to Google as their main source of information. In fact, some kids wouldn't look anywhere else but the Internet. So what does that mean for nonfiction books? Five years ago, everybody warned that fresh, interactive digital content would eventually replace old-fashioned books. However, last…

  19. Pictures into Books

    ERIC Educational Resources Information Center

    Adams, Linda; Lehman, Linda

    2007-01-01

    In this article, the authors describe a project that integrated computer technology skills with art history, photography, and layout/design. Approximately 160 fourth graders became photographers and created books on the following concepts: position words, numbers, colors, alphabet, shapes, and patterns. The books were professionally bound and…

  20. Books on acoustics

    NASA Astrophysics Data System (ADS)

    Shaw, Neil A.

    2004-05-01

    The legacy of a man is not limited to just his projects. His writings in many cases are a more lasting, and a definitely more accessible, monument. For 60 years, Leo L. Beranek has produced books on acoustics, acoustic measurements, sound control, music and architecture, noise and vibration control, concert halls, and opera houses in addition to teaching and consulting. His books are standard references and still cited in other books and in technical and professional articles. Many of his books were among, if not, the first comprehensive modern treatment of the subject and many are still foremost. A review of Dr. Beranek's many books as well as some anecdotes about the circumstances and consequences of same will be presented.

  1. Was the Devonian geomagnetic field dipolar or multipolar? Palaeointensity studies of Devonian igneous rocks from the Minusa Basin (Siberia) and the Kola Peninsula dykes, Russia

    NASA Astrophysics Data System (ADS)

    Shcherbakova, V. V.; Biggin, A. J.; Veselovskiy, R. V.; Shatsillo, A. V.; Hawkins, L. M. A.; Shcherbakov, V. P.; Zhidkov, G. V.

    2017-05-01

    Defining variations in the behaviour of the geomagnetic field through geological time is critical to understanding the dynamics of Earth's core and its response to mantle convection and planetary evolution. Furthermore, the question of whether the axial dipole dominance of the recent palaeomagnetic field persists through the whole of Earth's history is fundamental to determining the reliability of palaeogeographic reconstructions and the efficacy of the magnetosphere in shielding Earth from solar wind radiation. Previous palaeomagnetic directional studies have suggested that the palaeofield had a complex configuration in the Devonian period (419-359 Ma). Here we present new high-quality palaeointensity determinations from rocks aged between 408 and 375 Ma from the Minusa Basin (southern Siberia), and the Kola Peninsula that enable the first reliable investigation of the strength of the field during this enigmatic period. Palaeointensity experiments were performed using the thermal Thellier, microwave Thellier and Wilson methods on 165 specimens from 25 sites. Six out of eight successful sites from the Minusa Basin and all four successful sites from the Kola Peninsula produced extremely low palaeointensities (<10 μT). These findings challenge the uniformitarian view of the palaeomagnetic field: field intensities of nearly an order of magnitude lower than Neogene values (except during relatively rare geomagnetic excursions and reversals) together with the widespread appearance of strange directions found in the Devonian suggest that the Earth's field during this time may have had a dominantly multipolar geometry. A persistent, low intensity multipolar magnetic field and associated diminished magnetosphere would increase the impact of solar particles on the Earth's magnetosphere, ionosphere and atmosphere with potential major implications for Earth's climate and biosphere.

  2. Was the Devonian geomagnetic field dipolar or multipolar? Palaeointensity studies of Devonian igneous rocks from the Minusa Basin (Siberia) and the Kola Peninsula dykes, Russia

    NASA Astrophysics Data System (ADS)

    Shcherbakova, V. V.; Biggin, A. J.; Veselovskiy, R. V.; Shatsillo, A. V.; Hawkins, L.; Shcherbakov, V. P.; Zhidkov, G. V.

    2017-02-01

    Defining variations in the behaviour of the geomagnetic field through geological time is critical to understanding the dynamics of Earth's core and its response to mantle convection and planetary evolution. Furthermore, the question of whether the axial dipole dominance of the recent palaeomagnetic field persists through the whole of Earth's history is fundamental to determining the reliability of palaeogeographic reconstructions and the efficacy of the magnetosphere in shielding Earth from solar wind radiation. Previous palaeomagnetic directional studies have suggested that the palaeofield had a complex configuration in the Devonian period (419-359 Ma). Here we present new palaeointensity determinations from rocks aged between 408 and 375 Ma from the Minusa Basin (southern Siberia), and the Kola Peninsula to investigate the strength of the field during this enigmatic period. Palaeointensity experiments were performed using the thermal Thellier, microwave Thellier, and Wilson methods on 165 specimens from 25 sites. Six out of eight successful sites from the Minusa Basin and all four successful sites from the Kola Peninsula produced extremely low palaeointensities (< 10 μT). These findings challenge the uniformitarian view of the palaeomagnetic field: field intensities of nearly an order of magnitude lower than Neogene values (except during relatively rare geomagnetic excursions and reversals) together with the widespread appearance of strange directions found in the Devonian suggest that the Earth's field during this time may have had a dominantly multipolar geometry. A persistent, low intensity multipolar magnetic field and associated diminished magnetosphere would increase the impact of solar particles on the Earth's magnetosphere, ionosphere and atmosphere with potential major implications for Earth's climate and biosphere.

  3. Appalachian Stress Study: 2. Analysis of Devonian shale core: Some implications for the nature of contemporary stress variations and Alleghanian Deformation in Devonian rocks

    NASA Astrophysics Data System (ADS)

    Evans, Keith F.; Oertel, Gerhard; Engelder, Terry

    1989-06-01

    Detailed stress measurements in three boreholes penetrating horizontally bedded Devonian silt-stones, sandstones, and limestones above a prominent salt decollement in the Appalachian Plateau of western New York have revealed variations in horizontal stress magnitudes which correlate with lithologic and stratigraphic units in all wells. High differential stress levels (up to 20 MPa) were found in shales of very high clay content, contrary to the proposition that such materials have negligible long-term strength. Elastic modulus data show that stiffer beds generally host higher stress levels and suggest that sand/shale stress contrasts result in large part from elastic shortening of the section in response to regional ENE compression. No correlation between stress and Poisson's ratio was found. However, a major systematic drop in stress level within the generally massive shales, which occurs across a group of sand beds near the base of the Rhinestreet formation, appears to be of different origin. The stress offset corresponds to the top of a section which we conclude, on the basis of local and regional total strain data derived from chlorite fabric measurements, once hosted abnormally high pore pressures. The total strain data also suggest the entire section above the salt has been uniformly shortened during Alleghanian compression. To explain the stress discontinuity, two kinematic patterns for Alleghanian deformation of the Devonian section are proposed, both involving abnormal pore pressure development in the sub-Rhinestreet section in response to limited drainage of fluid. Drainage of this paleo-overpressure is the best available explanation of the stress offset, although an additional remnant stress component must also be present to satisfy the stress data precisely.

  4. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Alexander, Adrian W.; And Others

    1994-01-01

    The six articles in this section examine prices of U.S. and foreign materials; book title output and average prices; book sales statistics; U.S. book exports and imports; number of book outlets in the United States and Canada; and book review media statistics. (LRW)

  5. Literacy through the Book Arts.

    ERIC Educational Resources Information Center

    Johnson, Paul

    This book, a guide for adults to help children create their own original and creative books, demonstrates how constructing (writing and editing) their own books can be an engaging and highly educational experience for children. The book uses simple, easy-to-follow instructions to demonstrate how scores of different book forms can be made from a…

  6. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Greco, Albert N.

    1999-01-01

    Presents: "Prices of United States and Foreign Published Materials"; "Book Title Output and Average Prices"; "Book Sales Statistics, 1998"; "United States Book Exports and Imports: 1998"; "International Book Title Output: 1990-96"; "Number of Book Outlets in the United States and Canada";…

  7. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Alexander, Adrian W.; And Others

    1994-01-01

    The six articles in this section examine prices of U.S. and foreign materials; book title output and average prices; book sales statistics; U.S. book exports and imports; number of book outlets in the United States and Canada; and book review media statistics. (LRW)

  8. Book Trade Research and Statistics.

    ERIC Educational Resources Information Center

    Bosch, Stephen; Ink, Gary; Greco, Albert N.

    1999-01-01

    Presents: "Prices of United States and Foreign Published Materials"; "Book Title Output and Average Prices"; "Book Sales Statistics, 1998"; "United States Book Exports and Imports: 1998"; "International Book Title Output: 1990-96"; "Number of Book Outlets in the United States and Canada";…

  9. Literacy through the Book Arts.

    ERIC Educational Resources Information Center

    Johnson, Paul

    This book, a guide for adults to help children create their own original and creative books, demonstrates how constructing (writing and editing) their own books can be an engaging and highly educational experience for children. The book uses simple, easy-to-follow instructions to demonstrate how scores of different book forms can be made from a…

  10. The Shape of the Book.

    ERIC Educational Resources Information Center

    Manguel, Alberto

    2000-01-01

    Discusses the importance and impact of the shape of books, explaining that from the very beginning, readers demanded books in formats adapted to their intended uses. Describes the history of book production, beginning with Mesopotamian tablets dating from the 12th century B.C. and highlighting changes in books and book production into the 20th…

  11. Talking about Books: Karen Hesse.

    ERIC Educational Resources Information Center

    Beck, Cathy; Gwyn, Linda; Koblitz, Dick; O'Connor, Anne; Pierce, Kathryn Mitchell; Wolf, Susan

    1999-01-01

    Presents an interview with Karen Hesse, author of 12 books of fiction for young, middle, and older readers, and winner of the 1998 Newbery Award. Offers an overview of Hesse's books, organized into picture books, transition chapter books, and novels. Presents a discussion of the themes found in her books, highlighting children's discussion…

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

    USGS Publications Warehouse

    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.

  13. Early and Middle Devonian shelf-slope transition, southern Mahogany Hills, Eureka County, Nevada

    SciTech Connect

    Schalla, R.A.; Benedetoo, K.M.

    1989-03-01

    In the southern Mahogany Hills of Nevada, the abrupt lateral transition between the lower McColley Canyon Formation (Kobeh Member) and Beacon Peak (Sevy) dolomite (Lower Devonian) and the pinch-out of the Oxyoke Canyon sandstone into the upper Sadler Ranch formation (Middle Devonian) document lithofacies relationships between carbonate shelf and slope deposits. The McColley Canyon-Beacon Peak transition is marked by a change from thin-bedded dolomite and limestone with occasional chert nodules and scattered fossil material to poorly bedded, largely unfossiliferous, sandy dolomite. This change suggests shallowing and concomitant circulation restriction at the shelf edge during the early stages of platform (ramp) development. Measured sections in the vicinity of Combs Peak suggest that the location of the shelf edge is the result of both transgression and paleotopographic relief on the subjacent platform. A thin oxidized zone at the top of the Beacon Peak in section CP II, interpreted as a paleosol, indicates subaerial exposure of the outer shelf prior to renewed transgression and deposition of the Bartine Member. The location of the carbonate shelf edge is further documented by the westward pinch-out of unfossiliferous, arenaceous dolomites of the Oxyoke Canyon sandstone into fossiliferous foreslope dolomites of the Sadler Ranch formation. This facies change is the result of regression, which caused shoaling along the shelf edge. Lithofacies relationships exposed in the southern Mahogany Hills document two transgressive-regressive cycles and help to establish the location of an Early and Middle Devonian carbonate shelf-slope break in southern Eureka County.

  14. Early and Middle Devonian shelf-slope transition, southern Mahogany Hills, Eureka County, Nevada

    SciTech Connect

    Schalla, R.A. ); Benedetto, K.M. )

    1991-10-01

    In the southern Mahogany Hills the abrupt lateral transition between the lower McColley Canyon Formation (Kobeh Member) and the Beacon Peak (Sevy) Dolomite (Lower Devonian), and the pinch out of the Oxyoke Canyon Sandstone into the upper Sadler Ranch Formation (Middle Devonian), document lithofacies relationships between carbonate shelf and slope deposits. The McColley Canyon/Beacon Peak transition is marked by a change from thin-bedded dolomite and limestone with occasional chert nodules and scattered fossil material, to poorly bedded, largely unfossiliferous, sandy dolomite. This change suggests shallowing and concomitant circulation restriction at the shelf edge during the early stages of platform (ramp) development. Data from measured sections, in the vicinity of Combs Peak, suggest that the location of the shelf edge' was the result of both transgression and paleotopographic relief on the subjacent platform. A thin oxidized zone at the top of the Beacon Peak Dolomite on Combs Peak, interpreted as a paleosol, indicates subaerial exposure of the outer shelf prior to renewed transgression and deposition of the Bartine Member of the McColley Canyon Formation. The location of the carbonate shelf edge is further documented by the westward pinch out of unfossiliferous, arenaceous dolomites of the Oxyoke Canyon Sandstone into fossiliferous, fore-slope dolomites of the Sadler Ranch Formation. This facies change is the result of regression, which caused shoaling along the shelf edge. Lithofacies relationships Mahogany Hills document two transgressive-regressive cycles, and help to establish the location of an Early and Middle Devonian carbonate shelf-slope transition in southern Eureka County.

  15. Lithologies of the basement complex (Devonian and older) in the National Petroleum Reserve - Alaska

    USGS Publications Warehouse

    Dumoulin, Julie A.; Houseknecht, David W.

    2001-01-01

    Rocks of the basement complex (Devonian and older) were encountered in at least 30 exploratory wells in the northern part of the NPRA. Fine-grained, variably deformed sedimentary rocks deposited in a slope or basinal setting predominate and include varicolored (mainly red and green) argillite in the Simpson area, dark argillite and chert near Barrow, and widespread gray argillite. Chitinozoans of Middle-Late Ordovician and Silurian age occur in the dark argillite and chert unit. Sponge spicules and radiolarians establish a Phanerozoic age for the varicolored and gray argillite units, both of which contain local interbeds of chert-rich sandstone and silt-stone. Conglomerate and sandstone, also chert-rich but interbedded with mudstone and coal and of Early-Middle Devonian age, occur in the Topagoruk area; these strata formed in a fluvial environment. At East Teshekpuk, granite of probable Devonian age was penetrated. Brecciated, quartz-veined rock of uncertain protolith that may be part of the basement complex was encountered in the Ikpikpuk well. Seismic data indicate that angular unconformities truncate all sedimentary units of the basement complex in NPRA. Rocks correlative in age and lithofacies with the dark argillite and chert unit occur in the subsurface near Prudhoe Bay. Other argillite units in NPRA have similarities to basement rocks in the subsurface adjacent to ANWR and the Ordovician-Silurian Iviagik Group at Cape Lisburne, but lack the interbedded limestones found in the ANWR strata, and are less metamorphosed than, and compositionally distinct from, the Iviagik. The Topagoruk conglomerate and the East Teshekpuk granite resemble the Ulungarat formation and the Okpilak batholith, respectively, in the northeastern Brooks Range.

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

    NASA Astrophysics Data System (ADS)

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

    1998-05-01

    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 Icrioduswoschmidti/ I. w. hesperius (early 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 Palmatolepispunctata ( 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 363.4±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 by ˜20% over current estimates. We suggest that the duration of the Middle Devonian (Eifelian and Givetian) 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.

  17. New Plants from the Lower Devonian Pingyipu Group, Jiangyou County, Sichuan Province, China

    PubMed Central

    Edwards, Dianne; Geng, Bao-Yin; Li, Cheng-Sen

    2016-01-01

    Descriptions of Lower Devonian plants from Yunnan, South China, have revolutionized concepts of diversity and disparity in tracheophytes soon after they became established on land. Sichuan assemblages have received little attention since their discovery almost 25 years ago and require revision. With this objective, fieldwork involving detailed logging and collection of fossils was undertaken in the Longmenshan Mountain Region, Jiangyou County and yielded the two new taxa described here. They are preserved as coalified compressions and impressions that allowed morphological but not anatomical analyses. Yanmenia (Zosterophyllum) longa comb nov is based on numerous rarely branching shoots with enations resembling lycophyte microphylls, without evidence for vasculature. The presence of sporangia is equivocal making assignation to the Lycopsida conjectural. The plant was recently described as a zosterophyll, but lacks strobili. These are present in the second plant and comprise bivalved sporangia. The strobili terminate aerial stems which arise from a basal axial complex displaying diversity in branching including H- and K- forms. These features characterise the Zosterophyllopsida, although the plant differs from Zosterophyllum in valve shape. Comparisons indicate greatest similarities to the Lower Devonian Guangnania cuneata, from Yunnan, but differences, particularly in the nature of the sporangium border, require the erection of a new species, G. minor. Superficial examination of specimens already published indicate a high degree of endemism at both species and generic level, while this study shows that Yanmenia is confined to Sichuan and Guangnania is one of the very few genera shared with Yunnan, where assemblages also show a high proportion of further endemic genera. Such provincialism noted in the Chinese Lower Devonian is explained by the palaeogeographic isolation of the South China plate, but this cannot account for differences/endemism between the Sichuan and

  18. Late Devonian glacigenic and associated facies from the central Appalachian Basin, eastern United States

    USGS Publications Warehouse

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

    2010-01-01

    Late Devonian strata in the eastern United States are generally considered as having been deposited under warm tropical conditions. However, a stratigraphically restricted Late Devonian succession of diamictite- mudstonesandstone within the Spechty Kopf and Rockwell Formations that extends for more than 400 km along depositional strike within the central Appalachian Basin may indicate other wise. This lithologic association unconformably overlies the Catskill Formation, where a 3- to 5-m-thick interval of deformed strata occurs immediately below the diamictite strata. The diamictite facies consists of several subfacies that are interpreted to be subglacial, englacial, supraglacial meltout, and resedimented deposits. The mudstone facies that overlies the diamictite consists of subfacies of chaotically bedded, clast-poor mudstone, and laminated mudstone sub facies that represent subaqueous proximal debris flows and distal glaciolacustrine rhythmites or varvites, respectively. The pebbly sandstone facies is interpreted as proglacial braided outwash deposits that both preceded glacial advance and followed glacial retreat. Both the tectonic and depositional frameworks suggest that the facies were deposited in a terrestrial setting within the Appalachian foreland basin during a single glacial advance and retreat. Regionally, areas that were not covered by ice were subject to increased rainfall as indicated by wet-climate paleosols. River systems eroded deeper channels in response to sea-level drop during glacial advance. Marine facies to the west contain iceborne dropstone boulders preserved within contemporaneous units of the Cleveland Shale Member of the Ohio Shale.The stratigraphic interval correlative with sea-level drop, climate change, and glacigenic succession represents one of the Appalachian Basin's most prolific oil-and gas-producing intervals and is contemporaneous with a global episode of sea-level drop responsible for the deposition of the Hangenberg Shale

  19. New Plants from the Lower Devonian Pingyipu Group, Jiangyou County, Sichuan Province, China.

    PubMed

    Edwards, Dianne; Geng, Bao-Yin; Li, Cheng-Sen

    2016-01-01

    Descriptions of Lower Devonian plants from Yunnan, South China, have revolutionized concepts of diversity and disparity in tracheophytes soon after they became established on land. Sichuan assemblages have received little attention since their discovery almost 25 years ago and require revision. With this objective, fieldwork involving detailed logging and collection of fossils was undertaken in the Longmenshan Mountain Region, Jiangyou County and yielded the two new taxa described here. They are preserved as coalified compressions and impressions that allowed morphological but not anatomical analyses. Yanmenia (Zosterophyllum) longa comb nov is based on numerous rarely branching shoots with enations resembling lycophyte microphylls, without evidence for vasculature. The presence of sporangia is equivocal making assignation to the Lycopsida conjectural. The plant was recently described as a zosterophyll, but lacks strobili. These are present in the second plant and comprise bivalved sporangia. The strobili terminate aerial stems which arise from a basal axial complex displaying diversity in branching including H- and K- forms. These features characterise the Zosterophyllopsida, although the plant differs from Zosterophyllum in valve shape. Comparisons indicate greatest similarities to the Lower Devonian Guangnania cuneata, from Yunnan, but differences, particularly in the nature of the sporangium border, require the erection of a new species, G. minor. Superficial examination of specimens already published indicate a high degree of endemism at both species and generic level, while this study shows that Yanmenia is confined to Sichuan and Guangnania is one of the very few genera shared with Yunnan, where assemblages also show a high proportion of further endemic genera. Such provincialism noted in the Chinese Lower Devonian is explained by the palaeogeographic isolation of the South China plate, but this cannot account for differences/endemism between the Sichuan and

  20. Controls on porosity development in the Devonian Reservoir at Dolarhide Field

    SciTech Connect

    Saller, A.; Miller, J. ); Van Horn, D. )

    1990-05-01

    Devonian strata in the Dollarhide anticline originally contained 138 million bbl of oil. Porosity distribution is controlled by depositional facies. Devonian shata contain five main lithologies (from bottom to top). (1) Nonporous, microcrystalline chert and dolomite deposited as carbonate and siliceous mud in a basinal enviroment. (2) Burrowed chert-dolomite (10-35 ft thick) with variable porosity accumulated as siliceous sponge spicules and carbonate mud in a low-energy slope environment. (3) Laminated tripolitic chert (0-65 ft) deposited as a spiculitic sand in submarine channels in a slope environment. It has excellent porosity, mainly molds of sponge spicules. (4) Bioclastic limestone (47-92 ft) accumulated as a crinoidal grainstone in a moderate- to high-energy, outer shelf environment. Calcite cementation occluded virtually all porosity. (5) Upper dolomite (50-90 ft) consists of 1-3-ft-thick sequences of dolomitized peloidal grainstone capped by fine-grained chert. The grainstone was deposited in high-energy, shallow-subtidal and tidal-flat environments and has variable porosity. Deposition of the 200-ft-thick Devonian section occurred during a major progradation of shelf and slope facies. Porosity occurs in two stratigraphic zones separated by tight bioclastic limestone. The upper porosity zone (0-90 ft in upper dolomite) is heterogeneous with stratified porosity that bifurcates, coalesces, and pinches out. The lower porosity zone (laminated tripolitic chert and burrowed chert-dolomite) is homogeneous, with high porosity (commonly 25-35%), moderate permeability (5-20 md), and, in the southern part of the field, no distinct vertical permeability barriers. Thickness of the lower reservoir is variable (0-100 ft) with elongate thicks where sponge spicule sands filled channels.

  1. Global climatic changes during the Devonian-Mississippian: Stable isotope biogeochemistry of brachiopods

    NASA Astrophysics Data System (ADS)

    Brand, Uwe

    1989-12-01

    A progressive trend towards heavier δ 13C values of Devonian-Mississippian brachiopods from North America, Europe, Afghanistan and Algeria probably reflects expansion of the terrestrestrial and/or marine biomass and/or burial of carbon in soils/sediments. Oceanic Productivity crises, based on perturbations in the overall δ 13C trend, are recognized for the Mid Givetian, Early Famennian, Late Kinderhookian, Late Osagean and Early and Late Meramecian. The Givetian productivity crisis was probably accompanied by massive overturn of biologically toxic deep-ocean water. Temperature data, adjusted for the possible secular variation of seawater, support the hypothesis of global greenhouse conditions for the Devonian (mean of 30°C, mean of 26°C if extrinsic data are deleted) and icehouse conditions for the Mississippian (mean of 17°C). During the Mid Givetian, Frasnian and Early Famennian calculated water temperatures for tropical epeiric seas were generally above the thermal threshold limit (˜ 38°C) of most marine invertebrates or epeiric seawater was characterized by unusually low salinities (˜ pp ppt) or a combination of the two. These elevated water temperatures and/or low salinities, in conjunction with the postulated productivity crises and overturning of toxic deep waters are considered prime causes for the biotic crisis of the Late Devonian. In addition, a presumed expanding oxygen-minimum zone and general anoxia in the oceans prevented shallow-water organisms from escaping these inhospitable conditions. Re-population of the tropical seas occurred, after either water temperatures had dropped below the thermal threshold limit and/or salinities were back to normal, and oceanic productivity had increased due to more vigorous oceanic circulation, sometime during the Mid-Late Famennian. Migration of eurythermal, shallow- and deeper-water organisms into the vacant niches of the shallow seas was possible because of, generally, slightly lower sea levels, but, more

  2. Microtektite-like glass spherules in Late Devonian (367 MA) shales

    NASA Technical Reports Server (NTRS)

    Claeys, Philippe; Casier, Jean-Georges

    1993-01-01

    Glass spherules are found closely associated with the Frasnian-Famennain (FF) boundary in two sections, Senzeille and Hony, located in the Dinant basin in the South of Belgium. These spherules are interpreted, based on their chemistry and low water content, as impact produced microtektite-like glass. Craters of Late Devonian ages include the Siljan Ring (Sweden), Charlevoix (Quebec), and Taihu Lake (China). The occurrence of microtektite-like glass closely associated with the FF mass extinction is intriguing. The relationships between the impact and the extinction event deserve further study.

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

    PubMed

    Matsunaga, Kelly K S; Tomescu, Alexandru M F

    2016-04-01

    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. 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. 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. 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 uncoupled in lycophytes, and challenge the hypothesis that

  4. Evidence of land plant affinity for the Devonian fossil Protosalvinia (Foerstia)

    USGS Publications Warehouse

    Romankiw, L.A.; Hatcher, P.G.; Roen, J.B.

    1988-01-01

    The Devonian plant fossil Protosalvinia (Foerstia) has been examined by solid-state 13C nuclear magnetic resonance spectroscopy (NMR) and pyrolysis-gas chromatography-mass spectrometry (PY-GC-MS). Results of these studies reveal that the chemical structure of Protosalvinia is remarkably similar to that of coalified wood. A well-defined phenolic carbon peak in the NMR spectra and the appearance of phenol and alkylated phenols in pyrolysis products are clearly indicative of lignin-like compounds. These data represent significant new information on the chemical nature of Protosalvinia and provide the first substantial organic geochemical evidence for land plant affinity. -Authors

  5. Nitrate levels and the age of groundwater from the Upper Devonian sandstone aquifer in Fife, Scotland.

    PubMed

    McNeill, G W; Anderson, J; Elliot, T

    2003-03-01

    The tritium concentrations in 13 groundwater samples from boreholes throughout the Upper Devonian sandstone aquifer of Fife have been measured. Due to atmospheric variations in tritium concentrations over the last century, this radioactive tracer can be used as a groundwater age indicator. In this study, the groundwater tritium concentrations have allowed for the area to be divided into three zones, and the variable chemistry of the groundwater samples, including the problem of recent elevated nitrate levels in the Fife Aquifer, has been interpreted in terms of their relative ages.

  6. Impact ejecta layer from the mid-Devonian: possible connection to global mass extinctions.

    PubMed

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

    2003-06-13

    We have found evidence for a bolide impacting Earth in the mid-Devonian ( approximately 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.

  7. Dutrochus, a new microdomatid (Gastropoda) genus from the Middle Devonian (Eifelian) of west-central Alaska

    USGS Publications Warehouse

    Blodgett, R.B.

    1993-01-01

    A new gastropod genus, Dutrochus, is established for members of the family Microdomatidae that are characterized by a reticulate ornament of spiral cords and intersecting, finer collabral threads, with all but one spiral cord being of nearly equal strength, and the single remaining cord being of stronger (nearly twice the order) magnitude and being situated at the periphery. It is represented by the type and only known species, Dutrochus alaskensis n. gen. and sp., from the upper part (lower Eifelian) of the Lower? and Middle Devonian Cheeneetnuk Limestone. The genus is very close and nearly homeomorphic to the Permian microdomatid genus Glyptospira. -from Author

  8. Origins and relationships of colonial Heliophyllum in the upper Middle Devonian (Givetian) of New York

    USGS Publications Warehouse

    Oliver, W.A.

    1997-01-01

    Heliophyllum halli Milne-Edwards and Haime is common to abundant in many Lower and Middle Devonian stratigraphic units in New York. Most Heliophyllum are solitary, but both branching and massive colonies are known. Four 'populations' of colonial Heliophyllum in the Givetian part of the sequence are distinct, as is a fifth form that occurs through the section. Each of the colonial forms is interpreted as an independent derivative of solitary forms of H. halli. The relationships appear to range from infrasubspecific to specific, and it is suggested that the complex should be recognized as the Heliophyllum halli species group.

  9. Petrology and sedimentology of the Horlick Formation (Lower Devonian), Ohio Range, Transantarctic Mountains

    USGS Publications Warehouse

    McCartan, Lucy; Bradshaw, Margaret A.

    1987-01-01

    The Horlick Formation of Early Devonian age is as thick as 50 m and consists of subhorizontal, interbedded subarkosic sandstone and chloritic shale and mudstone. The Horlick overlies an erosion surface cut into Ordovician granitic rocks and is, in turn, overlain by Carboniferous and Permian glacial and periglacial deposits. Textures, sedimentary structures, and ubiquitous marine body fossils and animal traces suggest that the Horlick was deposited on a shallow shelf having moderate wave energy and a moderate tidal range. The source terrane probably lay to the north, and longshore transport was toward the west.

  10. Microtektite-like glass spherules in Late Devonian (367 MA) shales

    NASA Technical Reports Server (NTRS)

    Claeys, Philippe; Casier, Jean-Georges

    1993-01-01

    Glass spherules are found closely associated with the Frasnian-Famennain (FF) boundary in two sections, Senzeille and Hony, located in the Dinant basin in the South of Belgium. These spherules are interpreted, based on their chemistry and low water content, as impact produced microtektite-like glass. Craters of Late Devonian ages include the Siljan Ring (Sweden), Charlevoix (Quebec), and Taihu Lake (China). The occurrence of microtektite-like glass closely associated with the FF mass extinction is intriguing. The relationships between the impact and the extinction event deserve further study.

  11. Limestones of western Newfoundland that magnetized before Devonian folding but after Middle Ordovician lithification

    SciTech Connect

    Hodych, J.P. )

    1989-01-01

    A positive fold test and a negative conglomerate test help determine when and how stable remanence was acquired in the Middle Ordovician Table Head Group limestones of the Port au Port Peninsula of Newfoundland. The limestones magnetized after lithification and incorporation as clasts into a Middle Ordovician breccia. Hence, the limestones do not carry a detrital or other primary remanence despite their very low conodont color alteration index. The remanence may be thermoviscous or diagenetic and was acquired before Devonian folding. This suggests the need for caution in interpreting paleomagnetic results from other early Paleozoic limestones whose remanence resides in magnetite of blocking temperature lower than 400C.

  12. After Books, What? *

    PubMed Central

    Stetten, DeWitt

    1965-01-01

    The population explosion has evoked public interest and concern on the part of demographers. Consideration has been given to a variety of measures designed to curb the growth of population. The book explosion, also menacing, does not seem to have evoked analogous anxiety, and bibliographers, in contrast to demographers, prefer to adapt to the multiplication of books rather than to try to curb it. The intent of this paper is to explore the bibliographic analogies to several of the more popular devices designed to curb population increase. It is concluded that an effective restraint upon the writing and publishing of ever increasing numbers of books has yet to be discovered. PMID:16017387

  13. Modeling of Devonian shale gas reservoirs. Task 16. Mathematical modeling of shale gas production (2D model). Final report

    SciTech Connect

    Not Available

    1980-07-31

    The Department of Energy (DOE), Morgantown Energy Technology Center (METC) has been supporting the development of flow models for Devonian shale gas reservoirs. The broad objectives of this modeling program are to: (1) develop and validate a mathematical model which describes gas flow through Devonian shales; (2) determine the sensitive parameters that affect deliverability and recovery of gas from Devonian shales; (3) recommend laboratory and field measurements for determination of those parameters critical to the productivity and timely recovery of gas from the Devonian shales; (4) analyze pressure and rate transient data from observation and production gas wells to determine reservoir parameters and well performance; and (5) study and determine the overall performance of Devonian shale reservoirs in terms of well stimulation, well spacing, and resource recovery as a function of gross reservoir properties such as anisotropy, porosity and thickness variations, and boundary effects. During the previous annual period, a mathematical model describing gas flow through Devonian shales and the software for a radial one-dimensional numerical model for single well performance were completed and placed into operation. Although the radial flow model is a powerful tool for studying single well behavior, it is inadequate for determining the effects of well spacing, stimulation treatments, and variation in reservoir properties. Hence, it has been necessary to extend the model to two-dimensions, maintaining full capability regarding Klinkerberg effects, desorption, and shale matrix parameters. During the current annual period, the radial flow model has been successfully extended to provide the two-dimensional capability necessary for the attainment of overall program objectives, as described above.

  14. Library - Book Trade Relations

    ERIC Educational Resources Information Center

    Tuttle, Helen Welch

    1970-01-01

    The trend in relations between the library and the book trade has been in the direction of increased communication and cooperation. Organizational links between librarians, publishers, and booksellers are discussed. (Author/JS)

  15. Charter of the Book

    ERIC Educational Resources Information Center

    Unesco Bulletin for Libraries, 1972

    1972-01-01

    This declaration of the principles which should guide the treatment of books, both nationally and internationally, has been adopted by the international professional organizations of authors, publishers, librarians, booksellers and documentalists. (Author)

  16. Best Books of 1971

    ERIC Educational Resources Information Center

    Gerhardt, Lillian N.; And Others

    1971-01-01

    The forty-two titles selected by the editors of School Library Journal" are the best among over 2,100 new children's books reviewed since last January. Also included are 25 top notch Young Adult titles. (67 references) (MM)

  17. Smart Book Charts

    NASA Technical Reports Server (NTRS)

    Chinnapongse, Ronald L.

    2015-01-01

    Smart book charts for TPSM: Heatshield for Extreme Entry Environment Technology (HEEET), Conformal Ablative TPS (CA-TPS), 3D Woven Multifunctional Ablative TPS (3D MAT), and Adaptable, Deployable, Entry and Placement Technology (ADEPT).

  18. New Fashioned Book Burning.

    ERIC Educational Resources Information Center

    Gardner, Robert

    1997-01-01

    Reports on results of a teacher's experiment in book burning as a lesson accompanying the teaching of Ray Bradbury's "Fahrenheit 451." Discusses student reactions and the purpose of or justification for the experimental lesson. (TB)

  19. Batik to Book

    ERIC Educational Resources Information Center

    Tisinger, Betty

    1972-01-01

    Article describes how fifth- and sixth-graders first wrote Japanese Haiku poetry, then made books with batik covers. Materials needed and technique to follow are outlined, with photographs showing some details. (PD)

  20. Movie Books: A Bibliography.

    ERIC Educational Resources Information Center

    Top of the News, 1984

    1984-01-01

    This 22-item annotated bibliography lists books dealing with various aspects of children's films: monsters, television production, filmmaking, kids of the movies, animation, movie stunts, magic, movie animals, and photography. Publisher, publication date, and intended grade level are included. (EJS)

  1. Why Review Books? Editorial.

    ERIC Educational Resources Information Center

    Ree, Malcolm J.

    2003-01-01

    Discusses the book review as both science and art, the result of critical evaluation mixed with the expertise and predilections of the reviewer. Notes that there is no accounting for taste, but there is identifying and acknowledging it. (SLD)

  2. Academic Dishonesty [Book Review].

    ERIC Educational Resources Information Center

    Bazana, P. Gordon

    2002-01-01

    This book is a practical text that provides concrete solutions to problems related to academic dishonesty with an overview of research and theory and strategies for preventing, confronting, and managing the problem. (SLD)

  3. Views on Science Books.

    ERIC Educational Resources Information Center

    Stubbs, Harry C.

    1980-01-01

    Reviews six new children's science books that deal with the following topics: home computers; probability; spaces, shapes, and sizes; water; machines; and the development of energy resources from the ocean. (GT)

  4. New Fashioned Book Burning.

    ERIC Educational Resources Information Center

    Gardner, Robert

    1997-01-01

    Reports on results of a teacher's experiment in book burning as a lesson accompanying the teaching of Ray Bradbury's "Fahrenheit 451." Discusses student reactions and the purpose of or justification for the experimental lesson. (TB)

  5. Surprises (Children's Books).

    ERIC Educational Resources Information Center

    Freeman, Evelyn B.; And Others

    1995-01-01

    Presents brief annotations of 48 children's books that hold surprising creatures; surprises of magic and mystery; surprises of humor and trickery, surprises of growing up; cultural surprises; and surprising resources relating to poetry, dinosaurs, and science. (SR)

  6. The Black Books Roundup.

    ERIC Educational Resources Information Center

    Black Scholar, 1982

    1982-01-01

    Lists "Black and Black related" books available from American and some British publishing companies. Also provides lists of publishers and bookstores that carry works relevant to Blacks and Black studies. (GC)

  7. The Book Shelf

    ERIC Educational Resources Information Center

    Wheeler, Ronald, Ed.

    1978-01-01

    Annotations of 13 children's books with social studies themes published in 1977. Topics include racial background, conservation and recycling, American history, medieval and Shakespearean cultures, and rural life in the 1940s. (AV)

  8. Children's Books and Recordings.

    ERIC Educational Resources Information Center

    Young Children, 1993

    1993-01-01

    Provides publication data, short reviews, and age suitability recommendations for one audio cassette and nine books for children on various fiction and nonfiction topics published in 1991 and 1992. (MDM)

  9. Movie Books: A Bibliography.

    ERIC Educational Resources Information Center

    Top of the News, 1984

    1984-01-01

    This 22-item annotated bibliography lists books dealing with various aspects of children's films: monsters, television production, filmmaking, kids of the movies, animation, movie stunts, magic, movie animals, and photography. Publisher, publication date, and intended grade level are included. (EJS)

  10. Best Books of 1971

    ERIC Educational Resources Information Center

    Gerhardt, Lillian N.; And Others

    1971-01-01

    The forty-two titles selected by the editors of School Library Journal" are the best among over 2,100 new children's books reviewed since last January. Also included are 25 top notch Young Adult titles. (67 references) (MM)

  11. Lung transplant

    MedlinePlus

    ... diseases that may require a lung transplant are: Cystic fibrosis Damage to the arteries of the lung because ... BC; Clinical Practice Guidelines for Pulmonary Therapies Committee; ... Therapies Committee. Cystic fibrosis pulmonary guidelines: ...

  12. Rotational and accretionary evolution of the Klamath Mountains, California and Oregon, from Devonian to present time

    USGS Publications Warehouse

    Irwin, William P.; Mankinen, Edward A.

    1998-01-01

    The purpose of this report is to show graphically how the Klamath Mountains grew from a relatively small nucleus in Early Devonian time to its present size while rotating clockwise approximately 110°. This growth occurred by the addition of large tectonic slices of oceanic lithosphere, volcanic arcs, and melange during a sequence of accretionary episodes. The Klamath Mountains province consists of eight lithotectonoic units called terranes, some of which are divided into subterranes. The Eastern Klamath terrane, which was the early Paleozoic nucleus of the province, is divided into the Yreka, Trinity, and Redding subterranes. Through tectonic plate motion, usually involving subduction, the other terranes joined the early Paleozoic nucleus during seven accretionary episodes ranging in age from Early Devonian to Late Jurassic. The active terrane suture is shown for each episode by a bold black line. Much of the western boundary of the Klamath Mountains is marked by the South Fork and correlative faults along which the Klamath terranes overrode the Coast Range rocks during an eighth accretionary episode, forming the South Fork Mountain Schist in Early Cretaceous time.

  13. Belowground rhizomes in paleosols: The hidden half of an Early Devonian vascular plant

    NASA Astrophysics Data System (ADS)

    Xue, Jinzhuang; Deng, Zhenzhen; Huang, Pu; Huang, Kangjun; Benton, Michael J.; Cui, Ying; Wang, Deming; Liu, Jianbo; Shen, Bing; Basinger, James F.; Hao, Shougang

    2016-08-01

    The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant-soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils within a seasonal wet-dry climate zone. Rhizome networks contributed to the accumulation and pedogenesis of floodplain sediments and increased the soil stabilizing effects of early plants. Predating the appearance of trees with deep roots in the Middle Devonian, plant rhizomes have long functioned in the belowground soil ecosystem. This study presents strong, direct evidence for plant-soil interactions at an early stage of vascular plant radiation. Soil stabilization by complex rhizome systems was apparently widespread, and contributed to landscape modification at an earlier time than had been appreciated.

  14. Tectonic and depositional model of the Arabian and adjoining plates during the Silurian-Devonian

    SciTech Connect

    Husseini, M.I. )

    1991-01-01

    During the Late Ordovician and Early Silurian, the western part of the Arabian Peninsula was covered by polar glaciers that advanced from the south pole in African Gondwana. During this period, nondeposition, erosion, or marginal marine conditions prevailed in eastern and northern Arabia. When the glaciers melted in the Early Silurian, sea level rose sharply and the paleo-Tethys Ocean transgressed the Arabian and adjoining plates depositing a thick, organic-rich shale directly over the glaciogenic and periglacial rocks and related unconformities. The post-glacial sequence coarsens upward reflecting the passage of a coastline prograding northward from African and Arabian Gondwana to northern Arabia. A sea level drop in the Late Silurian placed the study area in a terrestrial environment; however, as sea level recovered in the Early Devonian, a carbonate sequence blanketed most of the area. The transgression, however, was interrupted by regional uplift and local orogenic movements in the Middle and Late Devonian. These movements constitute the onset of Hercynian tectonism, which resulted in erosion of the older sequences, depositional hiatuses, and regional facies changes.

  15. Reservoir zonation in Silurian-Devonian carbonates of Wells field, Dawson County, Texas

    SciTech Connect

    Mazzullo, L.J. )

    1992-04-01

    Wells field in Dawson County, Texas, has produced over 7.5 million bbl since 1955 from Silurian-Devonian carbonates. Although originally classified as a Devonian field, production there actually is out of the Silurian Wristen and Fusselman formations. Wells field is an extremely complex system of structured and stratigraphic reservoirs not easily characterized by traditional subsurface mapping techniques. Detailed lithologic analyses of well cuttings from 29 wells in and around this field were done to evaluate reservoir zonation and potentials for either new field development wells, or recompletions from existing well bores. These analyses have shown that paleotopographic highs on the Fusselman unconformity across the field created optimum sites for Fusselman dolomite reservoir development, and collateral development of Wristen reservoirs. The Wristen reservoirs are in the form of porous carbonate mounds that grew adjacent to the paleotopographically high areas, or simple compactionally fractured cherty carbonates over these highs. The recognition of Fusselman paleotopography in most wells is implied by thickness and facies changes in the overlying Wristen section. A certain amount of structure and facies-induced reservoir separation has been documented. The results of this study have been used to identify several areas of the field where each of the three reservoirs could be exploited for underdeveloped reserves.

  16. Late Devonian shale deposition based on known and predicted occurrence of Foerstia in Michigan basin

    SciTech Connect

    Matthews, R.D.

    1986-08-01

    The fossil Foerstia (Protosalvinia) marks a time zone within Late Devonian shale sequences in the eastern US. Its recent discovery in Michigan has led to more accurate correlations among the three large eastern basins. Subdivisions of the Devonian-Mississippi shale sequence in Michigan based on gamma-ray correlations reveal an idealized black shale geometry common to other eastern black shales, such as the Sunbury of Michigan and Ohio, the Clegg Creek of Indiana, the Dunkirk of Pennsylvania and New York, and the lower Huron of Ohio and West Virginia. In Michigan, Foerstia occurs at a stratigraphic position postulated to mark a major change in depositional conditions and source areas. This position strengthens the physical and paleontologic evidence for a formal division of the Antrim. Isopach maps of the shale sequence above and below Foerstia show a relatively uniform and continuous black shale deposit (units 1A, 1B, and 1C) below Foerstia. This deposit is unlike the wedge of sediment found above Foerstia, which is composed of a western facies (Ellsworth) and an eastern facies (upper Antrim) that should be combined in a single stratigraphic unit conforming to Forgotson's concept of a format.

  17. Devonian-Mississippian carbonate sequence in the Maiyumerak Mountains, western Brooks Range, Alaska

    SciTech Connect

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

    1990-05-01

    Essentially continuous, dominantly carbonate sedimentation occurred from at least the Early Devonian through the Mississippian in the area that is now the Maiyumerak Mountains, western Brooks Range. This succession is in striking contrast to Paleozoic sequences in the eastern Brooks Range and in the subsurface across northern Alaska, where uppermost Devonian-Mississippian clastic and Carboniferous carbonates unconformably overlie Proterozoic or lower Paleozoic metasedimentary or sedimentary rocks. Conodonts obtained throughout the Maiyumerak Mountains sequence indicate that any hiatus is less than a stage in duration, and there is no apparent physical evidence of unconformity within the succession. The sequence is best exposed northwest of the Eli River, where Emsian-Eifelian dolostones (Baird Group) are conformably overlain by Kinderhookian-Osagian sandy limestones (Utukok Formation) and Osagian-Chesterian fossiliferous limestones (Kogruk Formation) of the Lisburne Group. Conodont species assemblages and sedimentary structures indicate deposition in a range of shallow-water shelf environments. The sequence extends at least 30 km, from the Noatak Quadrangle northeast into the Baird Mountains Quadrangle; its easternmost extent has not been definitively determined. The Ellesmerian orogeny, thought to have produced the extensive middle Paleozoic unconformity seen through much of northern Alaska apparently had little effect on this western Brooks Range sedimentary succession.

  18. Sequence stratigraphy and depositional facies of the Silurian-Devonian interval of the northern Permian basin

    SciTech Connect

    Canter, K.L.; Geesaman, R.C. ); Wheeler, D. )

    1992-04-01

    The Silurian and Devonian intervals of the northern Central Basin platform area of west Texas and southeastern New Mexico include the Fusselman, Wristen, and Thirtyone formations and the Woodford Shale. The carbonate-rich Fusselman, Wristen, and Thirtyone formations record a transition from ramp to platform deposition. Oolite grainstones of the lower Fusselman Formation were deposited in a ramp setting during an Upper Ordovician/Lower Silurian transgression. The overlying crinoid packstones and grainstones represent shoals that developed along a break in slope separating the evolving platform from a southward-dipping starved basin. By the close of Fusselman deposition, the platform was well developed, with shallow peridtidal mudstones and wackestones, and high-energy grainstones deposited as near-parallel facies tracts over the platform area. The platform system became fully developed during the deposition of the Wristen Formation. Porous dolomitic peridtidal and platform margin facies grade downdip into nonporous, limy and argillaceous open-shelf facies. Platform facies are typified by numerous shallowing-upward parasequences that terminated at subaerial exposure surfaces. The rocks of the Lower Devonian Thirtyone Formation were deposited as a wedge that onlaps the exposed Silurian platform margin. This formation contains a porous, chert-rich, lowstand deposit; a transgressive disconformity; and variably porous, grain-rich highstand deposits representing an overall sea level rise. A major unconformity marks the contact between the karsted upper surface of the Thirtyone Formation and the overlying organic-rich, anoxic Woodford Shale.

  19. Sequence stratigraphic framework of the Devonian Guilmette Formation, Pahranagat Range, southeast Nevada

    SciTech Connect

    Estes, J.E. )

    1991-06-01

    The Middle and Late (Givetian through Frasnian) Devonian Guilmette Formation is a proven hydrocarbon reservoir at Grant Canyon Field, Railroad Valley, Nevada, and consists of limestones and dolomites with interbedded sandstones deposited on a broad, stable, shallow platform. The Guilmette was described and interpreted in the Pahranagat Range in Lincoln County, southeastern Nevada, approximately 64 mi southeast of Grant Canyon. The Guilmette Formation has been informally divided into three members based on lithology and depositional environment and separated by sharp contacts. The lower member consists of interbedded carbonate mudstones and wackestones deposited as subtidal to supratidal shallowing-upward cycles. This member appears to represent a relative sea level highstand. The upper member consists of interbedded carbonate mudstones, wackestone, and quartz sandstones deposited as peritidal shallowing-upward cycles. This member was deposited after a relative sea level fall. Thicknesses of each member are laterally consistent within fault blocks but are variable across faults. Interpretation of these cycles in a sequence stratigraphic framework will provide a relative sea level curve for the Middle to Upper Devonian in this area and will permit delineation of potential hydrocarbon reservoirs in the Guilmette basin wide. Preliminary analysis indicates the middle member is the best potential reservoir, while the sandstones of the upper member provide additional potential reservoirs. Within this framework, analogs to Railroad Valley may be found.

  20. Brine inclusions in halite and the origin of the Middle Devonian Prairie evaporites of Western Canada

    SciTech Connect

    Horita, J.; Weinberg, A.; Das, N.; Holland, H.D.

    1996-09-01

    Brines were extracted from fluid inclusions in Lower Salt halite of the Middle Devonian Prairie Formation in Saskatchewan, Canada. The brines were analyzed by ion chromatography and were found to be of the Na-K-Mg-Ca-Cl type. They do not fall along a simple evaporation trend. Brines from clear, diagenetic halite are significantly lower in Na{sup +} and higher in Mg{sup 2+}, and Cl{sup {minus}} than brines from cloudy, subaqueously formed halite with chevron structures. The isotopic composition of strontium and sulfur in anhydrite associated with the halites was found to be the same as that of Middle Devonian seawater. The composition of the inclusion brines can be derived from that of modern seawater by evaporation, extensive dolomitization of limestone, and albitization of clay minerals. Other evolution paths are, however, also feasible, and it is impossible to rule out effects due to the addition of nonmarine waters (hydrothermal solutions, surface runoff, and groundwater), or dissolutional recycling of existing evaporites within the Prairie evaporite basin. These analyses and published data on brine inclusions in halite from a number of Phanerozoid evaporite deposits show that the Na-K-Mg-Ca-Cl type brine is more common than the Na-K-Mg-Cl-SO{sub 4} type, which is expected from evaporation of modern seawater.

  1. Representatives of the family Actinostromatidae (Stromatoporoidea) in the Devonian of southern Poland and their ecological significance

    NASA Astrophysics Data System (ADS)

    Wolniewicz, Paweł

    2016-09-01

    Stromatoporoids of the family Actinostromatidae are common constituents of Givetian to Frasnian (Devonian) organic buildups. The species-level structure of actinostromatid assemblages from the Devonian of southern Poland is described in the present paper, with special emphasis on ecological factors that influenced species composition of the communities. Nine species of the genera Actinostroma and Bifariostroma are distinguished. Members of the family Actinostromatidae predominated in stromatoporoid assemblages within lower Frasnian carbonate buildup margins. The most diverse actinostromatid faunas were found within the middle Givetian Stringocephalus Bank, in the upper Givetian-lower Frasnian biostromal complex and in the lower Frasnian organic buildups. Species-level biodiversity was lowest within detrital facies which surrounded the Frasnian carbonate buildups. Species of Actinostroma with well-developed colliculi are commonest within the middle Givetian to early Frasnian coral-stromatoporoid biostromal complexes, whereas species with strongly reduced colliculi predominate early-middle Frasnian organic buildups. The skeletal structure of actinostromatids reflects environmental changes, documenting a transition from species with thin, close-set pillars and widely spaced laminae (common in the middle Givetian) to those with long, thick pillars and megapillars (in Bifariostroma), which were predominant during the early and middle Frasnian. The distribution of growth forms among species reveals a significant intraspecific variation. Species of Actinostroma can be either tabular or low domical, depending on the palaeoenvironmental setting. Thus, the present study confirms that stromatoporoid morphology was influenced by environmental conditions.

  2. Lithostratigraphy of Upper Devonian Scherr-Foreknobs and Lockhaven Formations near Allegheny front of central Pennsylvanian

    SciTech Connect

    Warne, A.G.; McGhee, G.R. Jr.

    1986-05-01

    Five well-exposed sections (at Madley, New Baltimore, Altoona, Milesburg, and Lockhaven) of Upper Devonian marine strata were measured and analyzed to refine lithologic and temporal correlations along the Allegheny Front of Pennsylvania. The members of the Scherr and Foreknobs formations (Minnehaha Springs, Mallow, Briery Gap, Blizzard, Pound, and Red Lock) are recognized as far north as Altoona. Farther north at Milesburg and Lockhaven, the lithology of the upper parts of the Lockhaven Formation are markedly different from the contiguous Foreknobs Formation, but the Minnehaha Springs member of the basal Scherr and lower-middle Lockhaven Formations is recognized in all sections studied. The Minnehaha Springs member (a 50 to 100-ft, resistant, medium-gray to red-gray sandy silt unit) is considered to be the result of a brief sea level lowering and is therefore nearly isochronous. The isochronous nature of the Minnehaha Springs member is substantiated by biostratigraphic data; therefore, it is considered the most reliable datum for correlating the sections of this study. The lithologic information of the six measured sections was augmented by 38 wells logs of oil and gas wells of the region. From the combined lithologic data, three generalized lithofacies cross sections were generated. These cross sections clearly indicate that: (1) the strike of the paleoshoreline was nearly parallel with the Allegheny Front; (2) a major delta lobe existed in central Pennsylvania during the Late Devonian; but (3) the size and influence of the delta on depositional environments was not constant through space and time.

  3. Belowground rhizomes in paleosols: The hidden half of an Early Devonian vascular plant

    PubMed Central

    Xue, Jinzhuang; Deng, Zhenzhen; Huang, Pu; Huang, Kangjun; Benton, Michael J.; Cui, Ying; Wang, Deming; Liu, Jianbo; Shen, Bing; Basinger, James F.; Hao, Shougang

    2016-01-01

    The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant−soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus. The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils within a seasonal wet−dry climate zone. Rhizome networks contributed to the accumulation and pedogenesis of floodplain sediments and increased the soil stabilizing effects of early plants. Predating the appearance of trees with deep roots in the Middle Devonian, plant rhizomes have long functioned in the belowground soil ecosystem. This study presents strong, direct evidence for plant−soil interactions at an early stage of vascular plant radiation. Soil stabilization by complex rhizome systems was apparently widespread, and contributed to landscape modification at an earlier time than had been appreciated. PMID:27503883

  4. A middle Devonian temperate water limestone-isotopes, stromatoporoids and shallow water facies

    SciTech Connect

    Wolosz, T.H.

    1995-09-01

    The Edgecliff Member of the Middle Devonian Onondaga Formation has long been of interest to exploration geologists because its pinnacle reefs and bioherms are potential natural gas reservoirs. Current evidence indicates that the Edgecliff was deposited in a shallow, temperate water environment suggesting that application of standard tropical carbonate models will be misleading. Three lines of evidence support the temperate water model for the Edgecliff. Carbon and oxygen isotopic analyses performed on 29 samples from the non-luminescent portions of 15 brachiopods with prismatic ultrastructure yield {delta}{sup 18}O values which are isotopically heavier than accepted values for Devonian sea-water, suggesting cool water conditions. The distribution of stromatoporoids (assumed warm water organisms) ranges from rare and small in the eastern part of New York State, to more common in Ontario, Canada. This trend in stromatoporoids appears to represent an increase in size and abundance as the distance from the paleo-equator decreases. Finally, previously unrecognized shallow water facies in the Edgecliff including thin, dolomitized and bioturbated carbonate muds, solitary rugosan biostromes and ridge-like fringing coral bioherms negate any possibility that the isotopic and paleobiologic data reflect deposition in deep, cooler waters as opposed to an overall temperate water environment.

  5. The groundwater age in the Middle-Upper Devonian aquifer system, Lithuania

    NASA Astrophysics Data System (ADS)

    Mokrik, R.; Mažeika, J.; Baublytė, A.; Martma, T.

    2009-06-01

    3H, δ13C and hydrochemical data were used to estimate the corrected groundwater age derived from conventional 14C age of dissolved inorganic carbon (DIC). The Middle-Upper Devonian aquifer system from the Baltic upland recharge area in eastern Lithuania towards the discharge area on the Baltic Sea coast in the west was considered. The concentration of total dissolved solids (TDS) in groundwater changes from 300 to 24,000 mg/L and increases downgradient towards the coast. The other major constituents have the same trend as the TDS. The hydrochemical facies of groundwater vary from an alkali-earth carbonates facies at the eastern upland area to an alkali-earth carbonate-sulfate and chloride facies at transit and discharge areas. Meteoric water percolating through the Quaternary and Devonian aquifers regulate the initial 14C activities of groundwater involving two main members of DIC: soil CO2 with modern 14C activity uptake and dissolution of 14C-free aquifer carbonates. Other sources of DIC are less common. 14C activity of DIC in the groundwater ranged from 60 to 108 pMC at the shallow depths. With an increase of the aquifers depth the dolomitization of aqueous solution and leakage of the “old” groundwater from lower aquifers take place, traced by lower activities (7-30 pMC).

  6. The climate change caused by the land plant invasion in the Devonian

    NASA Astrophysics Data System (ADS)

    Le Hir, Guillaume; Donnadieu, Yannick; Goddéris, Yves; Meyer-Berthaud, Brigitte; Ramstein, Gilles; Blakey, Ronald C.

    2011-10-01

    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 used a coupled climate/carbon/vegetation model to investigate the biophysical impacts of plant colonization on the surface climate through changes in continental albedo, roughness, thermal properties, and potential evaporation. From the Early to the Late Devonian, our model simulates a significant atmospheric CO 2 drop from 6300 to 2100 ppmv that is due to an increase in the consumption of CO 2 though continental silicate weathering. The continental drift and the climatic changes promoted by land plants explain this trend. The simulated CO 2 drawdown is paradoxically associated with unchanged temperatures. We show here that the CO 2 drop is counteracted by a large warming resulting from the surface albedo reduction caused by the appearance of an extended plant-cover. If CO 2 is consensually assumed as the main driver of the Phanerozoic climate, this paper demonstrates that, 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.

  7. Belowground rhizomes in paleosols: The hidden half of an Early Devonian vascular plant.

    PubMed

    Xue, Jinzhuang; Deng, Zhenzhen; Huang, Pu; Huang, Kangjun; Benton, Michael J; Cui, Ying; Wang, Deming; Liu, Jianbo; Shen, Bing; Basinger, James F; Hao, Shougang

    2016-08-23

    The colonization of terrestrial environments by rooted vascular plants had far-reaching impacts on the Earth system. However, the belowground structures of early vascular plants are rarely documented, and thus the plant-soil interactions in early terrestrial ecosystems are poorly understood. Here we report the earliest rooted paleosols (fossil soils) in Asia from Early Devonian deposits of Yunnan, China. Plant traces are extensive within the soil and occur as complex network-like structures, which are interpreted as representing long-lived, belowground rhizomes of the basal lycopsid Drepanophycus The rhizomes produced large clones and helped the plant survive frequent sediment burial in well-drained soils within a seasonal wet-dry climate zone. Rhizome networks contributed to the accumulation and pedogenesis of floodplain sediments and increased the soil stabilizing effects of early plants. Predating the appearance of trees with deep roots in the Middle Devonian, plant rhizomes have long functioned in the belowground soil ecosystem. This study presents strong, direct evidence for plant-soil interactions at an early stage of vascular plant radiation. Soil stabilization by complex rhizome systems was apparently widespread, and contributed to landscape modification at an earlier time than had been appreciated.

  8. Biogenic structures in upper Devonian storm deposits in Catskill Deltaic Complex, New York

    SciTech Connect

    Miller, M.F.

    1986-05-01

    Trace fossils and biogenic structures are moderately abundant in sandstones of the Genesee Group. These rocks are well exposed in a quarry at Gilbert Lake State Park, east-central New York, where they are interpreted as storm deposits. The biogenic structures given important information about the behavior of Devonian animals colonizing the freshly deposited sediment. Within the sandstones, trace-fossil diversity is low. The most abundant trace fossil is a small (1 mm diameter) branching burrow system (.Chondrites). Other common forms are vertical to horizontal meniscate burrows, horizontally oriented spreite-bearing forms (.Rhizocorallium-.Zoophycos), and vertical burrows (Skolithos). Except for Skolithos, the trace fossils are highly variable morphologically (e.g., the mensicate burrows apparently pass laterally into .Rhizocorallium-.Zoophycos). Commonly, the top 8-10 cm of inferred storm deposits are highly bioturbated, whereas the lower 20-25 cm typically are undisturbed. .Chondrites extends to depths more than 20 cm below the top of the burrowed zone, implying that its producer burrowed to equivalent depths. Two generalizations about the behavior of Devonian animals colonizing storm deposits can be made. (1) Their behavior was changeable, as indicated by diverse orientations and morphologic variability of the trace fossils. (2) They had a moderately deep infaunal habit, indicated by the abundance of burrowing in the top 8-10 cm of storm deposits.

  9. Upper Devonian-Tournaisian facies and oil resources of the Russian craton's eastern margin

    SciTech Connect

    Ulmishek, G.F.

    1987-01-01

    Upper Devonian-Tournaisian facies on the Russian craton's eastern margin indicate deposition in two distinct paleomorphic environments: bathimetrically expressed basins and shallow platforms. Shallow-water carbonate sedimentation persisted on the platforms, and black, thin-bedded, organic-rich shales and limestones of the Domanik facies were deposited in stagnant basins that stretched more than 2000 km from the Arctic Ocean to the Caspian Sea. Intermittently introduced clastic material and detrital carbonates formed progradational shelves. Barrier reefs along platform edges, atolls and reef mounds on basin margins, and smaller patch reefs on platforms were abundant. The basins were finally filled with Tournaisian (in the Timan-Pechora province) or basal Visean (in the Volga-Ural province) clastics. The North Caspian deep-water basin survived until the end of Early Permian time when it was filled with a thick salt formation. The organic-rich Domanik facies is the major source rock in the Volga-Ural, Timam-Pechora, and North Caspian petroleum provinces. About one-third of oil reserves occurs predominantly in structural traps in Middle Devonian-lower Frasnian clastics that directly underlie Domanik rocks. Most of the remaining two-thirds is found in reefs, especially in drape structures over the reefs in Tournaisian carbonates and basal Visean clastics. 61 refs., 16 figs.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Carbon isotope stratigraphy of Lochkovian to Eifelian limestones from the Devonian of central and southern Europe

    NASA Astrophysics Data System (ADS)

    Buggisch, Werner; Mann, Ulrich

    2004-09-01

    Lower to Middle Devonian carbonates of the Prague Syncline, the Carnic Alps, the Montagne Noire, and the Cantabrian Mountains were investigated for δ13Ccarb and δ13Corg. These values were measured on bulk rocks, selected components and cements. Many carbonates exhibit primary marine values, but some are altered by diagenesis. A δ13C curve can be presented for the latest Pridolian to Emsian time interval. Several sharp or broad positive excursions are obvious in the woschmidti-postwoschmidti, sulcatus, kitabicus, Late serotinus, and kockelianus conodont zones. The excursion at the Silurian Devonian boundary is known worldwide and therefore considered global in nature. Some of the others are described for the first time from central and southern Europe, and their global nature has to be verified by further investigations in other regions. Most excursions relate to and/or started during major regressions whereas sea-level highstands correspond to minimal δ13C values. Similar relationships between sea-level changes and δ13C have been observed from other early Palaeozoic intervals. The transgressive Choteč (?) and Kačák events are marked by positive isotope excursions, this type of combination is usually observed in late Palaeozoic to Cenozoic black shale events.

  12. Late Devonian magnetostratigraphy from a condensed limestone, Canning Basin, Western Australia

    SciTech Connect

    Hurley, N.F.; Van Der Voo, R.

    1988-01-01

    Detailed thermal demagnetization experiments have been carried out on 31 samples (93 specimens) of fore-reef limestones from the northern Canning basin, Western Australia. Samples are from a condensed sequence composed of deep-water (over 100 m) stromatolites in the marginal-slope facies of the Virgin Hills Formation. These stromatolites are made up of shrublike cyanobacterial filaments of Frutexites, an organism that probably precipitated iron hydroxide from seawater. Under the oxidizing conditions created by extremely slow sedimentation rates, it is likely that iron hydroxides were converted to hematite at or near the sediment-water interface. When plotted within the microstratigraphic framework for the study area, the observed characteristic directions from the sampled interval (14.5 cm thick) lie in five discrete normal and reversed polarity zones. The measured northeast-southwest declinations and shallow inclinations in these polarity zones probably record Late Devonian magnetostratigraphy on a centimeter scale. Using sedimentation rates from detailed conodont studies, a 56,000-year periodicity is calculated for Late Devonian polarity reversals. This value assumes no breaks in sedimentation, and is comparable to minimum lengths of late Mesozoic and Cenozoic polarity reversals. However, this study shows that iridium is present over the span of five magnetic reversals. Evidence therefore favors a biologic, rather than extraterrestrial, origin for anomalous iridium concentrations.

  13. Sediments and processes on a small stream-flow dominated, devonian alluvial fan, Shetland Islands

    NASA Astrophysics Data System (ADS)

    Allen, Philip A.

    1981-05-01

    The main conglomerate type of a small Devonian alluvial fan in Shetland, northern Britain, is an inverse to normally graded framework-supported gravel. The sedimentological details of these beds and fundamental considerations of the mechanics of movement of highly concentrated flows suggests that neither debris-flow nor grain-flow were responsible for the deposition of these conglomerates. On the contrary, these inverse to normally graded conglomerates were deposited by water as thick gravel sheets with little topographic relief, but broadly analogous to longitudinal bars. They were deposited under high aggradation conditions first on the rising and then on the falling flood. The high concentration of material in transport on the rising and peak flood was responsible for the polymodal and unstratified nature of the conglomerates. As the flood waned, normal grading was developed and a preferred horizontal fabric was produced under low concentrations of sediment. Other conglomerate types, comparatively of lesser importance, were deposited from highly concentrated clast dispersions and are notably richer in matrix and locally possess inverse grading. The hydrological environment was one of flashy discharges of short duration but of high velocity. Flow was dissipated rapidly, perhaps due to extreme water loss. This example from the Devonian of Shetland provides an interesting alternative to the mass-transport dominated fan models currently in vogue.

  14. Seeing into Books: Lessons from Rare Book School

    ERIC Educational Resources Information Center

    Hendrickson, Lois G.

    2012-01-01

    Recently, the author spent a week at Rare Book School (RBS) immersed in a course entitled "Teaching the History of the Book;" an investigation into different ways of thinking about, designing, and conducting a course on the history of the book. The goal was to learn how to convert teaching and outreach experiences in rare book collections from a…

  15. Seeing into Books: Lessons from Rare Book School

    ERIC Educational Resources Information Center

    Hendrickson, Lois G.

    2012-01-01

    Recently, the author spent a week at Rare Book School (RBS) immersed in a course entitled "Teaching the History of the Book;" an investigation into different ways of thinking about, designing, and conducting a course on the history of the book. The goal was to learn how to convert teaching and outreach experiences in rare book collections from a…

  16. Sharing Skills: Reach for a Book; Book Week Puzzle Packet.

    ERIC Educational Resources Information Center

    Bauer, Caroline Feller

    1986-01-01

    Reach for a Book is the theme for Children's Book Week 1986, and book presentations, activities, and exhibits to emphasize the joy of reading are listed. A Book Week Puzzle Packet provides two puzzles designed to reinforce the idea of using the card catalog to find materials on specific subjects. (EM)

  17. State Centers for the Book Show How "Books Change Lives."

    ERIC Educational Resources Information Center

    Bryant, Barbara

    1993-01-01

    Describes activities sponsored by some of the 28 state Centers for the Books, affiliated with the national Center for the Book at the Library of Congress, that were created to stimulate public interest in books, reading, and libraries. Highlights include electronic bulletin boards, satellite conferences, and children's book fairs. (LRW)

  18. The Children's Book Showcase 1975.

    ERIC Educational Resources Information Center

    Children's Book Council, New York, NY.

    The 1975 Children's Book Showcase committee selected 27 children's books for their excellent quality and design. Each of these books is given a two-page spread in the Showcase catalog. Information about the books, which are arranged alphabetically by title, includes author, title, publisher, artist, editor, art director, designer, production…

  19. The Children's Book Showcase 1975.

    ERIC Educational Resources Information Center

    Children's Book Council, New York, NY.

    The 1975 Children's Book Showcase committee selected 27 children's books for their excellent quality and design. Each of these books is given a two-page spread in the Showcase catalog. Information about the books, which are arranged alphabetically by title, includes author, title, publisher, artist, editor, art director, designer, production…

  20. Children's Book Awards Annual 1998.

    ERIC Educational Resources Information Center

    Berman, Matt; Dupuy, Marigny J.

    This publication reviews the books from the major national children's book awards and lists. The following awards are covered: John Newberry Awards, Randolph Caldecott Awards, Coretta Scott King Awards, Mildred L. Batchelder Awards, Pura Belpre, Boston Globe-Horn Book Award, and the National Book Award for Young People's Literature. The lists are…