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Sample records for hinterland east-central nevada

  1. Cretaceous to early Tertiary paleogeography in the hinterland of the Sevier thrust belt, east-central Nevada

    SciTech Connect

    Vandervoort, D.S.; Schmitt, J.G. )

    1990-06-01

    The Cretaceous to early Tertiary hinterland of the Sevier thrust belt in east-central Nevada underwent two periods of sedimentary basin development. The older (Early Cretaceous) episode is characterized by basins that formed coeval with deformation within a belt of contractional structures. Basins were characterized by periods of through-flowing fluvial drainage. The younger (Late Cretaceous to Eocene) episode of basin development was characterized by internally drained alluvial basins that subsequently expanded into more regional lacustrine basins. Basal alluvial detritus indicates that basin inception occurred as a result of rapid development of topographic relief. Synsedimentary tectonism was characterized by horizontal extension due to attainment of equilibrium topography in response to crustal thickening.

  2. A hydrogeochemical survey in east-central Nevada

    USGS Publications Warehouse

    McHugh, John B.; Miller, W. Roger; Ficklin, Walter H.

    1983-01-01

    A hydrogeochemical survey utilizing waters from springs and wells was conducted in east-central Nevada. None of the trace elements commonly associated with mineralization were found to be highly anomalous in the study area. Slightly anomalous values for some elements were found in the southern valleys of the study area and in a few scattered areas that contained old mines. Data from this study revealed no new areas of significant mineralization.

  3. Contrasting siliceous replacement mineralization, east-central Nevada

    SciTech Connect

    Barton, M.D.; Ilchik, R.P. . Dept. of Geosciences); Seedorff, C.E. )

    1993-04-01

    Fine-grained siliceous replacement of carbonate-bearing rocks (jasperoid) occurs in most mineral districts in east-central Nevada. In most of these occurrences, jasperoid contains Au and(or) Ag and little or no base metals, although concentrations and ratios vary significantly. Broadly, two end-members are distinguished: (1) silicification as an intermediate- to late-stage part of complex alteration associated with igneous centers, and (2) jasperoids lacking other associated alteration and having few or no associated igneous rocks. Within this region, siliceous replacements are found with all metallic ([+-] magmatic) suites. No single factor in these occurrences relates the distribution, metal contents, fluid geochemistry, igneous rocks and associated alteration. Summarizing these characteristics: geochemical and fluid inclusion evidence shows that fluids in igneous-related jasperoids can be high-salinity magmatic (Ely), low-salinity magmatic (McCullough Butte), or metoric (Ward). Fluids in igneous-poor systems are low-salinity, exchanged meteoric waters from which a minor magmatic component can not be excluded. At this level of detail, the best predictor of Ag:Au are the district-scale alteration characteristics. Siliceous replacement takes place in many kinds systems and probably requires no more than a cooling, mildly acidic hydrothermal fluid. Metal suites, other fluid characteristics, and geological environment all need to be considered in evaluating the significance of any jasperoid.

  4. Paleomagnetism of the Oligocene Kalamazoo Tuff: implications for middle Tertiary extension in east central Nevada

    USGS Publications Warehouse

    Hagstrum, J.T.; Gans, P.B.

    1989-01-01

    The Oligocene Kalamazoo Tuff (???35 Ma) was sampled for paleomagnetic analysis across a 100-km-wide zone of highly extended crust in east central Nevada to estimate between-site vertical axis rotations and thus the relative importance of strike-slip faulting to the mechanism of extension. The tilt-corrected data, with sources of error reduced or eliminated, exhibit a 28?? ?? 12?? clockwise rotation of the Schell Creek Range relative to the Kern Mountains region. This rotation implies differential extension accommodated by strike-slip faulting or N-S shortening. The paleomagnetic results also suggest that large changes in strike of layered units near faults with presumed strike-slip movement need not be the result of oroclinal bending, but could result from superimposed sets of orthogonal normal faults. -from Authors

  5. Tectonic sequence stratigraphy, Early Permian Dry Mountain trough, east-central Nevada

    SciTech Connect

    Snyder, W.S.; Gallegos, D.M.; Spinosa, C. ); Schwarz, D.L. )

    1991-06-01

    The Early Permian Dry Mountain trough (DMT) of east-central Nevada is one of several tectonic basins and associated uplifts that developed along the continenetal margin during the latest Pennsylvanian-Early Permian Dry Mountain tectonic phase. The sequence stratigraphy reflects a combination of eustatic sea level changes and tectonic uplift or subsidence. Fewer than one to only a few million years separate the development of sequence boundaries within the DMT. At this scale, differences among published eustasy curves preclude their use as definitive tools to identify eustatically controlled sequence boundaries. Nevertheless, available data indicate several pulses of tectonism affected sedimentation within the DMT. The authors are attempting to develop criteria to distinguish tectonic from eustatic sequence boundaries. Detailed biostratigraphic data are required to provide an independent check on the correlation of sequence boundaries between measured sections. For example, the same age boundary may reflect tectonic uplift in one part of the basin and subsidence in another. The uplift may or may not result in subaerial exposure and erosion. For those boundaries that do not result from subaerial exposure, lithofacies and biofacies analyses are required to infer relative uplift (water depth decrease) or subsidence (water depth increase). There are inherent resolution limitations in both the paleontologic and sedimentologic methodologies. These limitations, combined with those of eustasy curves, dictate the preliminary nature of their results.

  6. The geology of the Inconsolable Range, east-central Sierra Nevada, California

    SciTech Connect

    Hathaway, G.M; Reed, W.E. . Dept. of Earth and Space Sciences)

    1993-04-01

    Detailed mapping of the Inconsolable Range in the east-central Sierra Nevada reveals a structurally and lithologically complex region of multi-phase intrusions. Some plutons are compositionally-zoned [e.g., Inconsolable (100 Ma) and Lamarck (90 Ma)]; others may be the result of magma mixing. Intrusive borders vary from brittle to ductile and sharp to gradational, and are bounded by contact aureoles of varying metamorphic grade. A shear zone (Long Lake shear zone -- LLSZ) bounds the western margin of the Inconsolable Range for 8 km; this is truncated in the south by the Cretaceous Lamarck intrusive suite, and is tectonically overlain in the north by the Bishop Creek Pendant (Ordovician ). The LLSZ is a complex zone of interleaved septa of biotite schists, orthogneisses, aplitic screens, and calc-silicate gneisses approximately 500 to 800 m wide. Preliminary interpretation suggests that the LLSZ is the sheared remnant of a Triassic-Jurassic igneous terrane complete with metasedimentary pendants. Juxtaposition of greenschist facies meta-sedimentary rocks of the Chocolate Peak klippe over highly deformed amphibolite grade meta-igneous rocks of the LLSZ postdates movement along the LLSZ. Metamorphic grades suggest that deeper structural levels are exposed within the LLSZ near its southern terminus. Twenty plutonic lithologies have been mapped and informally named (e.g., Spotted biotite quartz diorite), including 3 compositionally-zoned plutons. Zonation within the Lamarck, Inconsolable, and Spotted intrusions are the result of multiple emplacement events into partially crystallized host plutons. Along the eastern border of the Lamarck intrusive suite field evidence indicates four separate intrusive events. The Inconsolable body is a compositionally-zoned biotite, clinopyroxene, quartz diorite with irregular granodiorite margins. The base of the Spotted intrusion appears to have been magmatically eroded by a pulse of the younger Lamarck intrusion.

  7. Basement Gravity Feature in East-central Nevada and West-central Utah and its Tectonic Implications

    NASA Astrophysics Data System (ADS)

    Ponce, D. A.; Tilden, J. E.

    2006-12-01

    A basement gravity map of east-central Nevada and west-central Utah, derived by removing the effects of Cenozoic deposits, reveals prominent gravity anomalies that reflect lateral density variations in pre-Cenozoic rocks throughout the region. Although some remanent artifacts may be present in the basement gravity map, in general, basement gravity features transcend Basin and Range structures, suggesting that the effects of the Cenozoic deposits were removed reasonably well. In a statewide analysis of basement gravity anomalies in Nevada, Blakely and Jachens (1991) suggest that a basement gravity low that extends across the central part of the state may reflect concealed silicic intrusions within the mid to lower crust. Within east-central Nevada and west-central Utah, this prominent NW-trending basement gravity low transects the region, and poorly correlates to exposed pre-Cenozoic rocks (Stewart and Carlson, 1978; Hintze, 1980). The western margin of the basement gravity low is surprisingly linear and trends about N30°W, a direction similar to that of the northern Nevada rift (e.g., Zoback et al., 1994), a mid- Miocene feature just to the west that may have preferentially followed a pre-existing basement structure (e.g., Ponce and Glen, 2003; 2005). Much of this basement gravity low occurs in a highly extended terrane between two structural troughs - the Butte and the Confusion synclinoriums (e.g., Hose, 1977; Gans and Miller, 1983), composed of downfolded Triassic to Permian rocks. The Butte synclinorium correlates to the western margin of the basement gravity low, whereas, the Confusion synclinorium is just east of the basement gravity low and directly correlates to a basement gravity high over the Confusion Range, Burbank Hills, and Mountain Home Range in west-central Utah (Hintze, 1980). This disconnect between the gravity anomaly polarity of the two synclinoriums may be related to underlying lithologic differences between the two areas such as the presence

  8. Demarcation of a Late Cretaceous(. ) thrust belt near Railroad Valley and Pine Valley in east-central Nevada

    SciTech Connect

    Cameron, G.J.

    1986-08-01

    Older-over-younger low-angle faults occur within a north-south-trending belt that includes the Pancake, Fish Creek, Diamond, and Carlin/Pinon Ranges in east-central Nevada. Collectively, these ranges form the western boundary of Nevada's only oil-producing basins, Railroad Valley and Pine Valley. These structures lie parallel to, but are east of and distinct from, the Roberts Mountain thrust. The faults involve eastern assemblage Paleozoic rocks in both upper and lower plates. The Chainman Shale is commonly the surface of decollement. A Late Cretaceous and possibly younger age is assigned to the faults, based on evidence that the Late Cretaceous Newark Canyon Formation is locally overridden by Paleozoic rocks in the Diamond and Pancake Ranges. The areal extent of this thrust belt was assessed using systematic lithostratigraphy from measured sections. This method was found useful and necessary owing to the disruptive influence of younger basin-and-range block faults on the earlier structures. Lithostratigraphic parameters used include formation thicknesses, color logs, grain-size logs, chert horizons, and quartz sandstone zones within Ordovician to Devonian rocks. It is reasoned that the boundaries of displaced blocks will show relatively sharp gradients of change in a number of lithostratigraphic parameters within the Paleozoic section.

  9. Controls on cross-sectional geometry of extensional basins, east-central Nevada -- A seismic-stratigraphic approach

    SciTech Connect

    Potter, C.J.; Grow, J.A.; Miller, J.J. )

    1993-04-01

    A 110-km regional seismic profile in east-central Nevada crosses Neogene east-tilted half-grabens in (from west to east) Railroad Valley (RRV), White River Valley, Cave Valley (CV), Muleshoe Valley and Lake Valley. Variations in the internal architecture of these basins may be related to two factors: (1) differences in structural evolution and (2) position of cross section (i.e., the seismic profile) with respect to major depocenters, accommodation zones, and other along-strike transitions in basin geometry. A detailed grid of seismic data in Railroad Valley and proprietary data from other basins show that without adequate three-dimensional seismic control, one should carefully consider factor (2) before generalizing about factor (1). As illustrations, the authors compare cross section derived from the seismic data across RRV (latitude of Grant Canyon) and CV (latitude of Sidehill Pass). In summary, data from RRV and CV illustrate the complexity of broad basin-bounding extensional fault zones and suggest that listric faulting and stratal rotation are characteristic of basin depocenters, whereas translation above planar bounding faults is characteristic of parts of extensional basins that are removed from the depocenter.

  10. Megabreccia deposits in an extensional basin: The Miocene-Pliocene Horse Camp Formation, east-central Nevada

    SciTech Connect

    Schmitt, J.G.; Brown, C.L. )

    1991-06-01

    Three varieties of megabreccia deposits are present in alluvial-lacustrine extensional basin fill of the Miocene-Pliocene Horse Camp Formation of east-central Nevada. Coherent debris sheets (150-300 m thick; up to 1,500 m long) consist of Oligocene-Miocene volcanic rock masses which are internally fractured yet retain their stratigraphic integrity. Fracture zones show variable amounts of displacement (up to 5 cm) and brecciation. These debris sheets overlie horizontally stratified sandstone and laminated claystone interpreted as playa deposits and are overlain by lithified grus. Emplacement of these coherent debris sheets was by landslide or block slide. Associated deposits of large boulders within playa facies suggest gliding of blocks broken from the edges of the landslides across wet playa surfaces. Large (1.6 - 2.4 km-long) allochthonous blocks consist of intact Paleozoic and Tertiary volcanic stratigraphic sequences which are brecciated and attenuated. Brecciation is accompanied in places by incorporation of muddy sand matrix. These blocks may be fragments of the upper plate of low-angle detachment faults which broke away as gravity-driven blocks from the nearby Horse Range and slid along the uplifted former detachment surface into the adjacent Horse Camp basin. Megabreccia deposits characterize Teritary extensional basins in western North America. Detailed analysis of their stratigraphic, sedimentologic, and structural relations can provide a better understanding of the complex tectonosedimentary history of these basins.

  11. Compilation of selected hydrologic data from the MX missile-siting investigation, east-central Nevada and western Utah

    USGS Publications Warehouse

    Bunch, R.L.; Harrill, J.R.

    1984-01-01

    Construction, water-level, and water-quality data for wells and site-description, discharge, and water-quality data for springs and streams in 37 hydrographic areas in Nevada and Utah are presented in the report. These data are grouped in tables, by area. Additional tables contain a summary of data and aquifer-test results for wells in valley-fill deposits at 42 sites in Nevada and Utah and for wells in carbonate rocks at five sites in Nevada. The data in the report were gathered by Ertec Western, Inc., or their subcontractors, for the U.S. Department of the Air Force as part of the MX missile-siting project and were originally presented in a number of individual reports. (USGS)

  12. Principal facts for gravity stations collected in 2010 from White Pine and Lincoln Counties, east-central Nevada

    USGS Publications Warehouse

    Mankinen, Edward A.; McKee, Edwin H.

    2011-01-01

    Increasing demands on the Colorado River system within the arid Southwestern United States have focused attention on finding new, alternative sources of water. Particular attention is being paid to the eastern Great Basin, where important ground-water systems occur within a regionally extensive sequence of Paleozoic carbonate rocks and in the Cenozoic basin-fill deposits that occur throughout the region. Geophysical investigations to characterize the geologic framework of aquifers in eastern Nevada and western Utah began in a series of cooperative agreements between the U.S. Geological Survey and the Southern Nevada Water Authority in 2003. These studies were intended to better understand the formation of basins, define their subsurface shape and depth, and delineate structures that may impede or enhance groundwater flow. We have combined data from gravity stations established during the current study with previously available data to produce an up-to-date isostatic-gravity map of the study area, using a gravity inversion method to calculate depths to pre-Cenozoic basement rock and to estimate alluvial/volcanic fill in the valleys.

  13. Compilation of Stratigraphic Thicknesses for Caldera-Related Tertiary Volcanic Rocks, East-Central Nevada and West-Central Utah

    USGS Publications Warehouse

    Sweetkind, D.S.; Du Bray, E.A.

    2008-01-01

    The U.S. Geological Survey (USGS), the Desert Research Institute (DRI), and a designee from the State of Utah are currently conducting a water-resources study of aquifers in White Pine County, Nevada, and adjacent areas in Nevada and Utah, in response to concerns about water availability and limited geohydrologic information relevant to ground-water flow in the region. Production of ground water in this region could impact water accumulations in three general types of aquifer materials: consolidated Paleozoic carbonate bedrock, and basin-filling Cenozoic volcanic rocks and unconsolidated Quaternary sediments. At present, the full impact of extracting ground water from any or all of these potential valley-graben reservoirs is not fully understood. A thorough understanding of intermontane basin stratigraphy, mostly concealed by the youngest unconsolidated deposits that blanket the surface in these valleys, is critical to an understanding of the regional hydrology in this area. This report presents a literature-based compilation of geologic data, especially thicknesses and lithologic characteristics, for Tertiary volcanic rocks that are presumably present in the subsurface of the intermontane valleys, which are prominent features of this area. Two methods are used to estimate volcanic-rock thickness beneath valleys: (1) published geologic maps and accompanying descriptions of map units were used to compile the aggregate thicknesses of Tertiary stratigraphic units present in each mountain range within the study areas, and then interpolated to infer volcanic-rock thickness in the intervening valley, and (2) published isopach maps for individual out-flow ash-flow tuff were converted to digital spatial data and thickness was added together to produce a regional thickness map that aggregates thickness of the individual units. The two methods yield generally similar results and are similar to volcanic-rock thickness observed in a limited number of oil and gas exploration

  14. Extensional geometries in the northern Grant Range, east-central Nevada - Implications for oil occurrences in Railroad Valley

    SciTech Connect

    Lund, K.; Perry, W.J. Jr. ); Beard, L.S. )

    1991-06-01

    Tertiary heterogeneous extension in the northern Grant Range, Nevada, is manifested by a stacked array of curviplanar low-angle attenuation faults that formed concurrent with arching. Attenuation was controlled by lithologic character, structural depth, and geometry of the arch. Extension appears to be greater on the west side of the range than on the east. On the east side of the range, the stacked array of low-angle attenuation faults is subparallel to bedding and attenuation is distributed across many stacked fault zones; except at highest crustal levels, these faults are blind. On the west side of the range, the low-angle attenuation faults of the stacked array merge into a single, major down-to-the-west fault zone across which as much as 19,000 ft of strata are omitted. Arching of the fault array resulted in an extensional culmination. Cross sections incorporating seismic and drill-hole data suggest that the low-angle attenuation faults (particularly the major down-to-the-west attenuation fault) seen in the range extend into Railroad Valley on the west side of the range with no significant offset by high-angle normal faults. Thus, the topographic expression of Grant Range and Railroad Valley may be due to the synchronous arching and low-angle faulting. These data indicate that both petroleum source and reservoir rocks in Railroad Valley oil fields are located in relatively immature but extensively fractured rocks of the upper plate to the extensional ramp. Lower plate rocks are metamorphosed, illustrate ductile behavior, and lack significant porosity and permeability.

  15. Regional seismic reflection profile from Railroad Valley to Lake Valley, east-central Nevada, reveals a variety of structural styles beneath Neogene basins

    SciTech Connect

    Potter, C.J.; Grow, J.A.; Lund, K.; Perry, W.J. Jr.; Miller, J.J.; Lee, M.W. )

    1991-06-01

    Two seismic reflection lines that compose a 90-km east-west profile at approximately 38{degree}25{prime}N latitude, east-central Nevada, help define the structure beneath Railroad Valley, White River Valley, the southern Egan Range, Cave Valley, Muleshoe Valley, the southern Schell Creek Range, and Lake Valley, Preliminary seismic interpretations are being integrated with ongoing geologic mapping, gravity, and magnetic studies and with drill-hole data along this transect. In the Grant Canyon oil field of Railroad Valley, a gently west-dipping normal fault appears to have controlled the development of the Neogene basin. The fault is clearly defined by fault-plane reflections and by terminations of east-dipping reflections from Tertiary and Paleozoic strata that have rotated toward the fault; the fault projects to nearby outcrops of a major low-angle extensional fault mapped in the Grant Range to the east. White River Valley at this latitude consists of three east-dipping half-grabens and two intervening basement highs. Two half-grabens in the western part of the valley are bounded by west-dipping faults with intermediate to steep dips. East-dipping reflections in the southern Egan Range correspond to a homoclinal Paleozoic panel overlain by a veneer of Late Cretaceous and early Tertiary rocks. The north end of Muleshoe Valley yields a narrow sag basin pattern between the southern Schell Creek Range and Dutch John Mountain, with no well-defined bounding faults. Lake Valley, on the east end of the profile, is a broad, complex basin containing normal faults with opposing dips. The progressive steepening of westerly dips in basin-fill beneath the west side of the basin suggests the presence of a major east-dipping listric fault.

  16. A Fold Province in the Hinterland of the Sevier Orogenic Belt in Eastern Nevada: A Valley and Ridge in the Basin and Range

    NASA Astrophysics Data System (ADS)

    Long, S. P.

    2014-12-01

    The overprinting effects of Cenozoic extensional tectonism hinder analysis of the style, geometry, and timing of Cordilleran contractional deformation in the hinterland of the Sevier fold-thrust belt in Nevada. To address this problem, a 1:250,000-scale paleogeologic map of eastern Nevada, showing spatial distributions of Paleozoic-Mesozoic rocks exposed beneath a Paleogene unconformity, divided out at the formation scale, is integrated with maps of dip magnitude for Paleozoic-Mesozoic and Tertiary rocks, published sedimentary thickness records, and a published reconstruction of Basin and Range extension, in order to define and regionally-correlate thrust faults and folds, and estimate the pre-extensional amplitude, wavelength, and limb dips of folds. A new structural province, the Eastern Nevada fold belt (ENFB) is defined, and consists of a 100-150 km-wide region containing as many as five 1st-order, N-trending folds that can be traced for map distances between 100-250 km, have amplitudes between 2-4 km, wavelengths between 20-40 km, pre-extensional limb dips typically between 10-30˚, and deform rocks as young as Jurassic and Early Cretaceous. No regional-scale thrust faults or decollemont horizons breach modern exposure levels in the ENFB. ENFB folds are interpreted to have formed above a deep (≥10 km below the Paleogene unconformity), blind decollemont or shear zone, perhaps the westward projection of the master decollemont of the Sevier fold-thrust belt. Two additional structural provinces of the Sevier hinterland, the Central Nevada thrust belt (CNTB) and Western Utah thrust belt (WUTB), represent zones of N-striking, E-vergent thrust faults and folds that each accommodated ca. 10 km of shortening. Both thrust belts branch northward off of the Sevier thrust belt, and are interpreted to represent contemporary, interior components of the Sevier thrust system. The CNTB, WUTB, and the intervening ENFB collectively record low-magnitude (a few 10's of km) upper

  17. Style and magnitude of Mesozoic thrust faulting in the hinterland of the Sevier thrust belt Pequop Mountains-Wood Hills-East Humboldt Range region, northeast Nevada

    SciTech Connect

    Camilleri, P.A. . Dept. of Geology and Geophysics)

    1993-04-01

    The Pequop Mountains (PM), Wood Hills (WH) and East Humboldt Range (EHR), NE Nevada, provide evidence that the hinterland of the Sevier thrust belt experienced large-magnitude Mesozoic shortening ([>=]55 km) and crustal thickening ([>=] 30 km). These ranges expose a structurally continuous crustal cross section of unmetamorphosed to high pressure upper amphibolite facies Triassic to Precambrian miogeoclinal strata. This sequence lies structurally beneath unmetamorphosed extensional klippen that omit metamorphic grade and crustal section, but also repeat stratigraphic units. Because they repeat stratigraphic units, the underlying miogeoclinal section, or footwall, must have once lain beneath a thrust fault (herein named the Windermere thrust). The footwall of the Windermere thrust was exhumed by two generations of top-to-the-W-NW low-angle normal faults that are distinguished by whether they are depositionally overlapped by Eocene volcanic rocks or if they cut the volcanic rocks in their hanging walls. The latter phase is associated with development of the mid-Tertiary extensional mylonitic shear zone in the EHR. An integration of geobarometric, metamorphic, and map data suggest (1) a NW dip of the footwall of the Windermere thrust with metamorphic facies belts trending perpendicular to dip direction and metamorphic grade increasing down dip, and (2) a top-to-the-SE sense-of-slip for the Windermere thrust. Assuming that the Windermere thrust comprised a flat on the youngest rocks exposed in the footwall (Triassic), the Mesozoic depth to the Windermere thrust in the northern PM is [>=] 7 km, in WH is [approximately]10--16 km, and in the EHR[>=]30 km. The Windermere thrust accommodated a minimum of 50 km of shortening associated with the Independence thrust is [>=] 5 km. These data indicate that the amount of hinterland shortening in NE Nevada greatly exceeds that to the south in the Eureka belt.

  18. Paleogeographic and paleotectonic setting of sedimentary basins in the Sevier thrust belt and hinterland, eastern Great Basin

    SciTech Connect

    Schmitt, J.G. . Dept. of Earth Sciences); Vandervoort, D.S. . Dept. of Geological Sciences); Suydam, J.D. . Dept. of Geology)

    1993-04-01

    The eastern Great Basin contains a sparse record of broadly distributed Cretaceous sedimentary rocks which record: evolution of intermontane basins during development of the Sevier (Sv)contractional orogen and incipient extensional collapse of the elevated Sv hinterland (east-central NV), and complex tectono-sedimentary interactions between frontal thrust belt structures and the western margin of the adjacent foreland basin. Palinspastic restoration of these strata and associated structures to pre-Tertiary extension positions reveals a clearer pictures of Cretaceous basin paleogeography and allows comparison with the Puna/Altiplano plateau and precordillera thrust belt of the Neogene Andean orogen. Two syntectonic stratal assemblages are present in east-central NV. Lower Cretaceous alluvial strata (Newark Canyon Fm) record basin development coeval with emergence of contractional structures in the Sv hinterland. Localized early Cretaceous basins were possibly piggyback immature; periods of open drainage to the to the east and south suggest connection with the nascent Sv foreland basin to the east (Cedar Mountain/Sanpete Fms) prior to major thrust loading in central Utah. Development of hinterland structures is almost recorded by Aptian-Albian foreland basin alluvial deposits in SW Utah (Dakota Fm) and southern Nevada (Willow Tank Fm). Upper Cretaceous to Eocene strata (Sheep Pass Fm) record inception of regionally abundant alluvial-lacustrine basins which developed in response to onset of latest Cretaceous extension and associated collapse of the Sv hinterland. Evolution of the structurally complex western margin of the Sv foreland basin is recorded in Cretaceous through Eocene strata deposited in: piggyback basins which were at times hydrologically connected to the adjacent foreland basins, and thrust-proximal portions of the foreland basin. These proximal areas are characterized by folding and faulting of basin fill and development of intrabasinal unconformities.

  19. Thermal evolution of a portion of the Sevier hinterland: The northern Ruby Mountains - east Humboldt Range and Wood Hills, northwestern Nevada

    NASA Astrophysics Data System (ADS)

    Hodges, K. V.; Snoke, A. W.; Hurlow, H. A.

    1992-02-01

    Conventional thermobarometry and Gibbs' Method modeling have been used to obtain new information pertaining to the Mesozoic-Tertiary thermal evolution of the Ruby Mountains-East Humboldt Range and Wood Hills metamorphic complexes, northeastern Nevada. Kyanite-grade assemblages from Clover Hill, in the extreme northeastern part of the East Humboldt Range, were produced at temperatures of 780-810 K and depths in excess of 35 km; previously published geochronologic data suggest an Early Cretaceous or Late Jurassic age for this event. The Clover Hill area subsequently experienced a major unroofing interval prior to Late Cretaceous time, during which it was brought roughly 20 km closer to the surface. The lack of stratigraphic evidence for substantial Cretaceous erosion in the region and the topology of the pressure-temperature paths for the Clover Hill samples suggest that the unroofing mechanism may have been tectonic denudation related to the relaxation of large topographic gradients produced by crustal thickening in the hinterland of the Sevier orogen. Metamorphic rocks at Clover Hill and within the Wood Hills core complex equilibrated at 820-900 K and 500-640 MPa (18-24 km) in Cretaceous time, prior to 115 Ma. Other parts of the Ruby Mountains-East Humboldt Range metamorphic complex, presently structurally separated from the Clover Hill sequence, were intruded extensively by Late Cretaceous granitic magmas and attained substantially higher temperatures than the Clover Hill-Wood Hills block. Sillimanite-grade assemblages from these areas apparently underwent roughly 10 km of unroofing and 130 K of cooling prior to final equilibration at 820-920 K and 360-430 MPa (13-16 km) during Oligocene extension.

  20. The Paleogene Evolution of the Cordilleran Hinterland

    NASA Astrophysics Data System (ADS)

    Cassel, E. J.; Smith, M. E.; Canada, A.; Stockli, D. F.; Breecker, D.

    2015-12-01

    Paleogene terrestrial and volcanic strata in the Cordilleran hinterland record changes in continental drainage, the dynamics of Farallon slab rollback, and the timing of the onset of surface-lowering extension. Sedimentology, geochronology, and stable isotope paleoaltimetry show that from the Eocene to the Oligocene, a high (up to 3.5 km), broad orogen stretched across Nevada, with a distinct crest that divided a continuous westward-draining slope extending to central California from an internally drained orogenic plateau in the east. Carbonate-rich lacustrine strata present across northeastern Nevada record prolonged Eocene continental drainage ponding and the transition from overfilled to balanced-fill lake conditions over time. Paleogene volcanic glass hydration waters across the Cordilleran hinterland at multiple latitudes show decreasing hydrogen isotope composition (δDglass) values eastward from the paleo-coast, suggesting higher than modern elevations in the hinterland. Detrital zircon U-Pb-He double dating indicates that the eastern Nevada Elko basin received sediment from both local basement and back-arc plutonic sources, and from the Challis volcanic field, demonstrating that Eocene hinterland lakes in Nevada were fed in part by a south-flowing drainage from a higher elevation terrain in central Idaho. From the Eocene into the Oligocene, sediment accumulation, volcanism, and unconformity migrated from northeast to southwest across Nevada, possibly in response to the migration of a regional topographic high caused by broad dynamic uplift and magmatism following Farallon slab rollback. Although rollback rearranged drainage networks across the Cordillera, δDglass values show that surface uplift did not exceed 500-900 m. Oligocene provenance data document significant sediment input from proximal volcanics, increased erosion of local basement sources, and isolation from extra-regional volcanics. Despite the long-term high gravitational potential energy of

  1. New Permian durhaminid cerioid corals from east-central California

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.

    2009-01-01

    Permian colonial corals from Artinskian to Kungurian strata in the Conglomerate Mesa area, Inyo Mountains, east-central California, include five new species, one of which is assigned to a new genus. The new taxa are: Malpaisia maceyi n. gen. and n. sp., Pararachnastraea bellula n. sp., P. delicata n. sp., P. owensensis n. sp., and Cordillerastraea inyoensis n. sp. These species, several of which compare most closely with other Artinskian and Kungurian species from eastern Nevada and northern Mexico, represent three distinct stocks that differentiated on an isolated submarine uplift offshore from the main part of the Cordilleran carbonate shelf.

  2. The relationship between normal and strike-slip faults in Valley of Fire State Park, Nevada, and its implications for stress rotation and partitioning of deformation in the east-central Basin and Range

    NASA Astrophysics Data System (ADS)

    Aydin, Atilla; de Joussineau, Ghislain

    2014-06-01

    This study expands on our earlier studies of the evolution of fracturing and faulting in the Jurassic aeolian Aztec Sandstone exposed over a large area in the Valley of Fire State Park, southeastern Nevada. Based on a nearly three-dimensional data set collected from 200-m-high cliff-face exposures with stair-case morphology composed of steep and flat parts, we find that a series of inclined, relatively low-angle normal faults and their splay fractures are precursors of the strike-slip fault network that we previously documented. We discuss the significance of this finding in terms of the tectonics of the broader area, stress rotation, partitioning of deformation, and the development of fracture clusters with compartmentalization of the structures as a function of spatial, depositional and deformational domains.

  3. An application of Petrochronology: U/Th-Pb geochronologic rates of burial and exhumation in the Cordilleran hinterland, northern Nevada, USA

    NASA Astrophysics Data System (ADS)

    Hallett, B. W.

    2014-12-01

    Monazite and zircon U/Th-Pb dating and yttrium thermometry results from metapelitic rocks of the northern East Humboldt Range, Nevada provide insight into the tectonic evolution of the North American Cordillera. Combining a petrologic approach with in situ U/Th-Pb SHRIMP geochronology gives constraints on the timing and rates of burial and exhumation. When integrated with the results from studies of the intrusive igneous and structural evolution of a complexly deformed crustal block, a broad picture of the behavior of the thickened middle crust in an orogenic wedge begins to emerge. In samples from the upper limb of the south verging Winchell Lake nappe, monazite cores giving moderate YPO4 components yield a mean U-Pb age of 82.8 ± 1.3 Ma representing initial growth near garnet zone conditions. A cycle of burial and heating giving way to decompression and melting, followed by zircon growth accompanied by low YPO4 monazite growth giving a wide range of ages (77.1-62.4 Ma) apparently documents cooling and melt crystallization. Monazite core and zircon ages from these samples bracket the time frame for this cycle through peak pressure and then temperature. Rates of burial therefore are ~1.0­-4.5 mm/year for the Winchell Lake nappe. Migmatitic pelites from the Lizzies Basin area, structurally beneath the Winchell Lake nappe give U-Pb monazite age brackets of 96.5-79.4 Ma, yielding a narrower range of burial rates, ~0.5-2.0 mm/year. Calculated exhumation rates for the same rocks from both the upper limb of the Winchell Lake nappe and the Lizzies Basin area fall between ~0.4 and 1.7 mm/year. Rapid burial followed by rapid exhumation is consistent with thickening by an overthrust mechanism followed by vertical ductile thinning, underplating, erosion, and/or normal faulting. Exhumation is generally slower than estimates for exhumation of metamorphic core complexes north of the Snake River Plain calculated by Bendick and Baldwin (2009). This may represent a difference in

  4. Planning applications in East Central Florida

    NASA Technical Reports Server (NTRS)

    Hannah, J. W. (Principal Investigator); Thomas, G. L.; Esparza, F.; Millard, J. J.

    1974-01-01

    The author has identified the following significant results. This is a study of applications of ERTS data to planning problems, especially as applicable to East Central Florida. The primary method has been computer analysis of digital data, with visual analysis of images serving to supplement the digital analysis. The principal method of analysis was supervised maximum likelihood classification, supplemented by density slicing and mapping of ratios of band intensities. Land-use maps have been prepared for several urban and non-urban sectors. Thematic maps have been found to be a useful form of the land-use maps. Change-monitoring has been found to be an appropriate and useful application. Mapping of marsh regions has been found effective and useful in this region. Local planners have participated in selecting training samples and in the checking and interpretation of results.

  5. New fusulinids from Lower Permian turbidites at Conglomerate Mesa, southeastern inyo Mountains, east-central California

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.

    2009-01-01

    Seven previously unrecognized fusulinid species from Lower Permian (Wolfcampian and Leonardian) turbidites near Conglomerate Mesa in east-central California, four of which are named as new species, are here described and figured. The four new species are Schwagerina merriami, S. wildei, Parafusulina mackevetti, and Skinnerella rossi. These fusulinid species have close affinities to similar taxa in Texas and northeastern Nevada, and they are distinct from some other faunas of slightly different age in the Conglomerate Mesa area that are dominated by endemic species and other species with Eastern Klamath Mountains affinities.

  6. Landsat analysis of east-central Tennessee

    SciTech Connect

    Clark, B.; Kent, R.; Noel, J.A.; Sers, S.

    1986-05-01

    Regional Landsat analysis was completed in an area of east-central Tennessee, about 65 mi southeast of Nashville. The study area encompassed the eastern edge of the Great Basin, the Highland Rim, and the western edge of the Cumberland Plateau. The area is roughly bounded on the north by Interstate 40 and on the south by US Highway 41. The study was undertaken to learn the relationships between the fracture production of gas from the McMinnville field and the surface areal extent and orientation of the fractures, if any. Production from the McMinnville gas field is primarily from fractures in the Trenton limestone. Density logs show that formations penetrated have very low interstitial porosity. The eastern edge of the Great Basin is underlain by sediments of lower paleozoic age, which are successively overlain by limestone and shale of Mississippian age in the Highland Rim. Sandstone, shale, and coal of Pennsylvanian age top the Cumberland Plateau and its erosional outliers on the eastern edge of the Highland Rim. Three sets of lineaments were evident on the enhanced Landsat imagery. The dominant set trends northeast-southwest, and parallels the thrust faults of the Sequatchie Valley and the Valley and Ridge province to the east. The second set trends at right angles to the first, and the third set trends at some angle to the other two. On the west side of the study area is a broad arcuate anomaly that is not expressed on topographic maps nor in the outcrop patterns of geologic maps, but may be a feature of the rim of the Great Basin. Subsurface mapping of the McMinnville field, which is still proprietary, indicates that the field is a small dome of low closure with several normal faults located parallel to the lineament systems.

  7. 29. View East, Central Court, Showing typical interior detail and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. View East, Central Court, Showing typical interior detail and lunettes above. Two lunettes present, Public Works Administration, 1938-42. - Ives Memorial Library, 133 Elm Street, New Haven, New Haven County, CT

  8. Farewell to Parachute Professors in East-Central Europe.

    ERIC Educational Resources Information Center

    Ognianova, Ekaterina

    1995-01-01

    Examines the work of 10 North American journalism educators who taught in 15 midcareer training programs for journalists in East-Central Europe from 1991-93. Asks how North American journalists teach in intercultural settings and how they changed their methods to suit the setting. Concludes that North American journalists should continue their…

  9. Educational Reforms in East-Central Europe: The Hungarian Example.

    ERIC Educational Resources Information Center

    Berend, Ivan T.

    1980-01-01

    Examines educational trends in East-Central European countries during the twentieth century, with emphasis on educational development in Hungary since World War II. Information is presented on objectives, problems, educational level of the working population at various periods, and prognosis for the 1980s. (Author/DB)

  10. Crustal structure of east central Oregon: Relation between Newberry Volcano and regional crustal structure

    NASA Astrophysics Data System (ADS)

    Catchings, R. D.; Mooney, W. D.

    1988-09-01

    A 180-km-long seismic refraction transect from the eastern High Cascades, across Newberry Volcano, to the eastern High Lava Plains is used to investigate the subvolcanic crustal and upper mantle velocity structure there. Near-surface volcanic flows and sedimentary debris (1.6-4.7 km/s), ranging from 3 to 5 km in thickness, overlie subvolcanic Basin and Range structures. East and west of Newberry Volcano, the subvolcanic basement (5.6 km/s) has been downwarped, producing 5-km-deep basins. The midcrust (8- to 28-km depth) is characterized by velocities ranging from 6.1 to 6.5 km/s and varies laterally in thicknesses. The lower crust is characterized by art unusually high velocity (about 7.4 km/s), and its geometry mirrors the subvolcanic basement geometry. The Moho is located at a depth of 37 km and represents a transition to an upper mantle velocity of 8.1 km/s. The shallow subsurface (1.2 km) beneath Newberry Volcano is characterized by high-velocity (5.6 km/s, versus 4.1 km/s for the surrounding area) intrusions and appears to be located on a basement high. Beneath the seismic refraction array at Newberry Volcano, an absence of low-velocity anomalies suggests that large silicic magma chambers do not exist in the upper crust, but apparent high attenuation of the seismic wave field may be consistent with either partial melts in small volumes, elevated crustal temperatures, and/or poor geophonerecording site coupling. The east central Oregon velocity structure is nearly identical to that of the northwestern Nevada Basin and Range and the Modoc Plateau of northeastern California, and variations in the deep crustal structure about Newberry Volcano are consistent with tectonism involving crustal underplating, melting, and extension. If paleomagnetic estimates of extension in the east central Oregon area are correct, the North American continent experienced significant growth through extension, underplating, and volcanism in east central Oregon. Comparison of east

  11. Estimates of Late Cenozoic extension, east-central Idaho

    SciTech Connect

    Janecke, S.U.. . Dept. of Geology)

    1993-04-01

    Late Cenozoic normal faults define the southwest flanks of the Lost River, Lemhi and Beaverhead Ranges in east-central Idaho. Cross sections and structural analysis suggest that throws along the central parts of the Lost River and Lemhi faults range from about 2 to 5 km. If the Beaverhead fault has a similar throw, then Miocene to Recent extension of east-central Idaho ranged 5 to 15%. However, three additional Late Cenozoic normal faults (the Hawley Mountain, Goldburg and Barney faults) bound a NW-trending horst between the Lost River and Lemhi Ranges in the Hawley Mountain and Donkey Hills area. The horst-bounding normal faults are inferred to have formed during Late Cenozoic time because: (1) the faults parallel the NW to NNW strike of Late Cenozoic normal faults in the region, (2) scattered Quaternary fault scarps coincide with the Barney fault, (3) steep topographic fronts define parts of the Goldburg and Hawley Mountain faults, (4) the Hawley Mountain fault displaces two Eocene normal faults, and (5) gravity lows are present in the hanging walls of the Barney and Goldburg faults. Left-lateral separation across the inferred NE-dipping Barney fault suggests 2--3 km of throw, assuming dip-slip displacement. Throw across the Goldburg fault, which uplifts Oligocene basin-fill deposits in its footwall, is at least 500 m. Although two of the horst-bounding normal faults have not offset Quaternary surficial deposits, estimated slip across these faults have not offset Quaternary surficial deposits, estimated slip across these faults is similar to slip across the prominent range-front faults in the region. Therefore, estimated Late Cenozoic extension of east-central Idaho along a NE-SW cross section through the Hawley-Goldburg horst is about 10 to 20%.

  12. Tectonic development of southwestern Montana and east-central Idaho

    SciTech Connect

    Lopez, D.A.

    1984-07-01

    The region of southwestern Montana and east-central Idaho, north of the Snake River plain and east of the Idaho batholith, has been affected by a complex sequence of orogenic events from the Proterozoic through Holocene time. Deposition of Proterozoic Belt Supergroup rocks and rocks of similar age in east-central Idaho occurred in basins that were clearly fault controlled. Many of these faults were reactivated repeatedly at later times and controlled or affected the development of younger tectonic features. This study encompasses the entire width of the Sevier orogenic belt in this part of the Cordilleran fold and thrust belt. The thrust belt comprises several major eastward-transported thrust plates that are successively younger to the east. These plates juxtapose distinct stratigraphic packages that were deposited in eugeoclinal, miogeoclinal, and continental platform settings. As a consequence, the thrust plates can be distinguished on the basis of facies and thickness distribution as well as, to some extent, structural style. In southwest Montana, Sevier-type structures overlap with, and butt against, basement-involved Laramide structures. The extension of southwest Montana basement trends into Idaho suggests that this overlap may extend into east-central Idaho. Superimposed on these older structures are mid-Tertiary to Holocene normal faults that formed present-day basins and ranges. Many of these are reactivated older fault zones, some of which can be shown to have Precambrian ancestry. The region has excellent oil and gas potential, because reservoir and source rocks and trapping mechanisms are all clearly present. However, an understanding of the effect of overlapping tectonic elements is necessary to predict accurately where favorable rock packages are preserved.

  13. Manganese resources of the Cuyuna range, east-central Minnesota

    SciTech Connect

    Beltrame, R.J.; Holtzman, R.C.; Wahl, T.E.

    1981-01-01

    The Cuyuna range, located in east-central Minnesota, consists of a sequence of argillite, siltstone, iron-formation, graywacke, slate, and quartzite of early Proterozoic age. Manganese-bearing materials occur within the iron-rich strata of the Trommald Formation and the Rabbit Lake Formation. Computer-assisted resource estimates, based on exploration drill hole information, indicate that the Cuyuna range contains a minimum of 176 million metric tons (MMT) of marginally economic manganiferous rock with an average grade of 10.46 weight percent manganese. The calculated 18.5 MMT of manganese on the Cuyuna range could supply this country's needs for this important and strategic metal for nearly 14 years. An additional resource of 6.9 MMT of manganese metal is available in the lower grade deposits The vast majority of these calculated resources are extractable by current surface mining techniques.

  14. Strategies for financing energy projects in East Central Europe

    SciTech Connect

    Fortino, S.E.

    1995-12-01

    This paper discusses financing options available for energy (power/steam) projects in East Central Europe. It is intended to be an overview and practical guide to such options in today`s environment. A survey is made of the principal multilateral and other financial institutions providing funding and/or credit support in the region. These include the European Bank for Reconstruction and Development, the World Bank, the International Finance Corporation, the export credit agencies, and the commercial banks. Specific guarantee and other support mechanisms which some of these institutions provide are covered, including the latest developments. In addition to loan financing, potential sources of equity financing are discussed. Next, a description of the credit rating process by such institutions as Standard and Poor`s, and an example of a successful rating effort in the Czech Republic, lead into a discussion of accessing foreign and domestic bond markets to finance energy projects in the region.

  15. Traces of Old Glaciations in East-central Alaska

    NASA Astrophysics Data System (ADS)

    Duk-Rodkin, A.; Barendregt, R. W.; Weber, F.

    2001-12-01

    The East-central Alaska record of glaciations is similar to that preserved in the west-central Yukon. Surficial geologic mapping of the Yukon-Tanana upland has indicated at least 5 glacial periods including at least one early Holocene. The two earliest glaciations are of pre-Mid Pleistocene age and followed regional erosion and renewed uplift ca.4 Ma. The earliest glaciation of west-central Yukon occurred between 2.6 and 2.9 Ma, forming a continuous carapace of ice covering all the mountain ranges except for a small part of the Dawson Range. This first glaciation was also the most extensive in the region, and resulted in the NW diversion of Yukon River into Alaska by the Cordilleran Ice Sheet. Stratigraphic evidence of 6 glaciations of pre-Mid Pleistocene age is preserved in the western Canadian sector of the Tintina Trench. The limits of these glaciations have been mapped in Yukon on the basis of glacial landforms and the distribution of erratics. Although morphological features of older glaciations (Plio-Pleistocene) are generally not well preserved, there is relatively good control on the distribution of glacial features for two of the older glaciations in Mt.Harper, Alaska. Stratigraphic evidence of at least 3 older glaciations is found in the Goodpastor River. An initial magnetostratigraphic study of three sites in east-central Alaska have yielded normal magnetic polarities only. The sites are:(1) a relatively weathered lowermost till outcropping along Goodpastor River on the Yukon-Tanana upland,(2) an extremely weathered high level moraine (609m) on the western side of the Gerstle River, near Granite Mt.in the Alaska Range and (3)ca.914m pediment containing glacial erratics and a luvisol at its surface, located on Tok River, Tanana Valley, Alaska Range. The normal polarity of the first site likely indicates a Brunhes age rather than a normal subchron within the Matuyama Reversed Chron based on the modest degree of weathering of the till and lack of any

  16. Floods of August 1967 in east-central Alaska

    USGS Publications Warehouse

    Childers, Joseph M.; Meckel, James P.; Anderson, Gary S.

    1972-01-01

    East-central Alaska had record floods near Fairbanks following extensive rains of August 8-20, 1967. Precipitation during this period totaled as much as 10 inches, which is close to the average annual precipitation for this area. The most extensive flooding occurred in the White Mountains northeast of Fairbanks and along the major streams draining those mountains. Some of the major streams flooded were the Salcha, Chena, Chatanika, Tolovana, and lower Tanana Rivers, and Birch Creek west of Circle. Peak discharges on some streams in the flood area were from two to four times the probable 50-year flood. The peak discharge of 74,400 cubic feet per second of the Chena River at Fairbanks, from 1,980 square miles of drainage area, was 2.6 times the 50-year flood. The rise of ground-water levels in the Tanana River flood plain to the land surface during the flood caused foundation failures and prevented drainage of subsurface structures. Above-normal ground-water levels existed until the middle of September. Total flood damage was estimated in excess of $85 million. Six lives were reported lost, and about 12,000 persons were evacuated during the flood. This report has been prepared to furnish hydrologic data for development planning. Included are discussions of antecedent streamflow, meteorology of the storm, descriptions of floods, flood damage, flood frequency, ground-water conditions, and stages and discharges of major streams for August 1967.

  17. Ferron sandstone - stratigraphy and reservoir analogs, East-Central Utah

    SciTech Connect

    Anderson, P.B.; Ryer, T.A.; Chidsey, T.C. Jr.

    1996-06-01

    The Ferron Sandstone (Upper Cretaceous) crops out along the west flank of the San Rafael Swell of east-central Utah. Exposures were described on photomosaics to better define the stratigraphy, to enhance facies prediction, and establish rules for reservoir modeling within fluvial-deltaic rocks. Major regressive cycles are recognized as parasequence sets composed of several to many parasequences. Each of the seaward-stepping parasequence sets recognized in the Ferron begins with a rapidly thickening and stratigraphically climbing, wave-modified shoreface. In later stages of progradation, deposition is dominated by river influences. Continued regression of the seaway is recorded in outcrop and shows a complex history of delta lobe progradation, switching, and abandonment. Onlapping and stacking of parasequences creates a collage of potential reservoir sweet spots, baffles, and barriers within a parasequence set. Shoreface and delta-front deposits of the older parasequences are commonly eroded by younger distributary and meanderbelt systems that fed younger parasequences of the parasequence sets. The result is numerous and locally thick channel sandstone bodies incised into shoreface and delta-front deposits. Published studies and recently completed work show that upper shoreface, stream mouth-bar, and channel sandstones constitute the best potential reservoir rocks within the Ferron Sandstone.

  18. Water movement in till of east-central South Dakota

    SciTech Connect

    Craven, S.J.; Ruedisili, L.C.; Barari, A.

    1985-01-01

    Factors that control the flow of water through till are poorly understood. Hydrographic analyses, field hydraulic conductivity measurements, and major-ion sampling were conducted on weathered and unweathered tills at 22 sites in east-central South Dakota. Water from a buried outwash aquifer was also chemically analyzed and carbon age dated. The upper part of most till has been weathered and exhibits extensive secondary permeability. Hydraulic conductivity values range from 10/sup -7/ to 10/sup -4/ cm/sec; typically 10 to 200 times higher than the hydraulic conductivity of unweathered till. Hydraulic gradients within weathered tills average seven times lower than within unweathered till. Water infiltrating below plant roots is believed to principally recharge and discharge the weathered till. Total dissolved solids were significantly higher in the weathered till than in the unweathered till. Water extracted from unweathered till is, in turn, up to three time higher in major-ion concentrations than water from the underlying outwash aquifer. Carbon-14 age dates from outwash aquifer water exceed 9000 years before present. Results indicate that Tittle to no water passes from the weathered till through the unweathered till into the buried outwash aquifer. Discharge from the weathered till is hypothesized to be primarily local lateral flow to sloughs, streams and ponds, combined with evapotranspiration losses during periods of high water table.

  19. Nevada's Little Smoky Valley: A high potential Valley in the Paleozoic Fairway

    SciTech Connect

    Hansen, M.W. )

    1993-08-01

    Little Smoky Valley, located in east-central Nevada between Railroad valleys, has been demonstrated to have all of the elements essential for oil production: generating source rock, fracture-porous reservoir rock, tight top and lateral seals as the trapping mechanism, and closed structure. The valley lies in the heart of a mature Chainman (Mississippian) oil-generating fairway, which is coincident with the western part of the Antler foreland basin, and runs from Pine Valley in the north to Railroad Valley in the south. A southeastern Little Smoky Valley prospect, at the point where Eureka, White Pine, and Nye counties converge, was defined by using a combination of geological, geochemical, and geophysical methods, as well as remote sensing. There was 880 ft of shows in the first of two stagecoach wells, which is now interpreted to be just below the oil-water contact within the freshwater drive zone of the carrier beds. Minor Sevier hinterland overthrusting was demonstrated to have occurred in this mostly extensional province. The immediate subthrust in the first Stagecoach well contains palynomorphs dated as earliest Tertiary, and a syntectonic conglomerate exists at the very lip of the thrust just 1500 ft to the east. Thus, neither Antier (Roberts Mountains) thrusting nor post-Sevier low-angle normal detachment faulting is indicated. Although Sevier thrusting does exist, the west-east offset is minor.

  20. Public health in pre-colonial east-central Africa.

    PubMed

    Waite, G

    1987-01-01

    This study is the first of its kind to suggest that a rich public health tradition existed in east-central Africa before the twentieth century, and that the tradition can be reconstructed historically. It breaks with earlier studies of public health history for the region in that it does not define public health on the basis of western institutions and activities. The definition of public health that is used in this study makes a simple equation between politics and medicine. It includes all activities that ruling authorities undertake to promote the well-being of the societies over which they have charge. Thus rainmaking and sorcery control, the principal services in traditional African societies, are the focus of this study. Evidence is presented here of the control exercised by kings, chiefs, priests over these services in various societies located in southeastern Zaire, southern Tanzania, Zambia, Malawi, northern Mozambique, and Zimbabwe. The cases are all set in the pre-colonial period, before the twentieth century and the beginning of most written records. The evidence is derived primarily, though not exclusively, from non-written sources, such as archaeology, linguistic, and ethnographic records. The best data are those that come from cultural exchanges between people, for historical records are created in this way. Therefore, the cases discussed here all involve contacts between immigrant and autochthonous groups. The political histories of these contacts are already known. What this study does is link up those traditions with independently-acquired evidence of change in medical traditions. Political change often, but not always, led to change in public health institutions. The control of ruling elites over health services is thus made apparent by the manner in which new medical institutions were implanted when new political authorities arose. PMID:3547688

  1. Raising the Curtain. A Report with Recommendations on Academic Exchanges with East Central Europe and the USSR. East Central Europe Information Exchange Report 1.

    ERIC Educational Resources Information Center

    Burn, Barbara B.

    This report provides an overview of the changes in the development of academic exchange activity between the United States, the Soviet Union, and East Central Europe in the context of far-reaching reforms throughout the region. It also explores the factors which may facilitate or inhibit further growth in academic exchanges. The report begins with…

  2. Seismic reflection evidence for two phase development of Tertiary basins from east-central Nevada

    SciTech Connect

    Liberty, L.M.; Heller, P.L.; Smithson, S.B. . Dept. of Geology and Geophysics)

    1993-04-01

    Two east-west seismic reflection profiles crossing Antelope Valley, Smokey Valley, Railroad Valley and Big Sand Springs Valley demonstrate the evolution of Tertiary extension from broad sags to narrow, fault-bounded basins. Seismic reflection data was acquired for the Anschutz Corporation by the Digicon Corporation during the winter of 1988/1989. Reprocessing of a 480 channel, 60 fold, dynamite source experiment enabled good imaging of the basin stratigraphy. These data suggest two distinct phases of basin development occurred, separated by a regional unconformity. The early phase is characterized by development of a broad basin riddled with many small offset normal faults. The later phase shows a narrowing of the basin and subsidence along one dominant structure, an apparent planar normal fault. The unconformity separating the two phases of extension marks a transition from broad subsidence to local asymmetric tilting that took place over a short period of time relative to sedimentation rates. Antelope Valley and Railroad Valley clearly show strong evidence for two phase development, whereas Smokey Valley represents mostly the early phase and Big Sand Springs Valley represents only the later phase of extension. The absence of dating within the basins precludes the authors from determining if the abrupt tectonic transition within the basins resulted from differences in local strain rates or amounts, or was due to changes in regional stress fields.

  3. Alligator ridge district, East-Central Nevada: Carlin-type gold mineralization at shallow depths

    USGS Publications Warehouse

    Nutt, C.J.; Hofstra, A.H.

    2003-01-01

    Carlin-type deposits in the Alligator Ridge mining district are present sporadically for 40 km along the north-striking Mooney Basin fault system but are restricted to a 250-m interval of Devonian to Mississippian strata. Their age is bracketed between silicified ca. 45 Ma sedimentary rocks and unaltered 36.5 to 34 Ma volcanic rocks. The silicification is linked to the deposits by its continuity with ore-grade silicification in Devonian-Mississippian strata and by its similar ??18O values (_e1???17???) and trace element signature (As, Sb, Tl, Hg). Eocene reconstruction indicates that the deposits formed at depths of ???300 to 800 m. In comparison to most Carlin-type gold deposits, they have lower Au/Ag, Au grades, and contained Au, more abundant jasperoid, and textural evidence from deposition of an amorphous silica precursor in jasperoid. These differences most likely result from their shallow depth of formation. The peak fluid temperature (_e1???230??C) and large ??18OH2O value shift from the meteroric water line (_e1???20???) suggest that ore fluids were derived from depths of 8 km or more. A magnetotelluric survey indicates that the Mooney Basin fault system penetrates to mid-crustal depths. Deep circulation of meteoric water along the Mooney Basin fault system may have been in response to initial uplift of the East Humboldt-Ruby Mountains metamorphic core complex; convection also may have been promoted by increased heat flow associated with large magnitude extension in the core complex and regional magmatism. Ore fluids ascended along the fault system until they encountered impermeable Devonian and Mississippian shales, at which point they moved laterally through permeable strata in the Devonian Guilmette Formation, Devonian-Mississippian Pilot Shale, Mississippian Joana Limestone, and Mississippian Chainman Shale toward erosional windows where they ascended into Eocene fluvial conglomerates and lake sediments. Most gold precipitated by sulfidation of host-rock Fe and mixing with local ground water in zones of lateral fluid flow in reactive strata, such as the Lower Devonian-Mississippian Pilot Shale.

  4. Tectonic implications of facies patterns, Lower Permian Dry Mountain trough, east-central Nevada

    SciTech Connect

    Gallegos, D.M.; Snyder, W.S.; Spinosa, C. )

    1991-02-01

    Paleozoic tectonism is indicated by a study of a west-east facies analysis transect across the northern portion of the Lower Permian Dry Mountain trough (DMT). In an attempt to characterize the Early Permian basin-filling sequences, three broadly recognizable facies packages have been identified across the DMT: the western margin facies and the central basin facies of the DMT and an eastern shelf facies. In the western margin facies of the basin, pulses of tectonic activity are recorded at McCloud Spring in the Sulphur Springs Range. Here, shallow open-marine carbonate overlies eroded Vinini Formation and, in turn, is unconformably overlain by basinal marine carbonate. An unconformity also marks the contact with the overriding prograding coarse clastic facies. These abrupt transitions suggest the sediments were deposited in a tectonically active area where they preservation of Waltherian sequences is unlikely to occur. Similarly abrupt transitions are evident in the western part of the central basin facies. At Portuguese Springs n the Diamond Range, a thin basal marine conglomerate delineates Lower Permian sedimentation over the Pennsylvanian Ely Formation. Coarsening-upward basinal carbonate strata of pelagic, hemipelagic, and turbidite components overlie the basal conglomerate. this progression of sediments is unconformably overlain by a subaerial sequence of coarse clastic deposits. Within the eastern part of the central basin facies in the Maverick Spring Range, the Lower Permian sediments are open-marine siltstone, wackestone, packstone, and grainstone. The sediments are assigned to a gradually sloping ramp, indicating the effects of tectonism on this margin of the basin were subdued.

  5. Block rotation in east-central Alaska: a framework for evaluating earthquake potential?

    USGS Publications Warehouse

    Page, R.A.; Plafker, G.; Pulpan, H.

    1995-01-01

    Geologic and seismic data reveal a set of parallel, active, strike-slip faults in east-central Alaska between the Denali and Tintina fault systems. The faults strike northeast to north-northeast, at a high angle to the bounding dextral fault systems, and exhibit sinistral slip. This hypothesizes that this set of faults divides the crust into long blocks that are rotating clockwise in response to northerly compression resulting from Pacific-North American plate convergence. It is suggested that these faults have produced most of the large historical earthquakes in east-central Alaska between the Alaska Range and the Yukon River. -Authors

  6. Regional implications of new chronostratigraphic and paleogeographic data from the Early Permian Darwin Basin, east-central California

    USGS Publications Warehouse

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

    2015-01-01

    The Darwin Basin developed in response to episodic subsidence of the western margin of the Cordilleran continental shelf from Late Pennsylvanian (Gzhelian) to Early Permian (late Artinskian) time. Subsidence of the basin was initiated in response to continental truncation farther to the west and was later augmented by thrust emplacement of the Last Chance allochthon. This deep-water basin was filled by voluminous fine-grained siliciclastic turbidites and coarse-grained limestone-gravity-flow deposits. Most of this sediment was derived from the Bird Spring carbonate shelf and cratonal platform to the northeast or east, but some came from an offshore tectonic ridge (Conglomerate Mesa Uplift) to the west that formed at the toe of the Last Chance allochthon. At one point in the late Artinskian the influx of extrabasinal sediment was temporarily cut off, resulting in deposition of a unique black limestone that allows precise correlation throughout the basin. Deep-water sedimentation in the Darwin Basin ended by Kungurian time when complex shallow-water to continental sedimentary facies spread across the region. Major expansion of the Darwin Basin occurred soon after the middle Sakmarian emplacement of the Last Chance allochthon. This tectonic event was approximately coeval with deformation in northeastern Nevada that formed the deep-water Dry Mountain Trough. We herein interpret the two basins to have been structurally continuous. Deposition of the unique black limestone is interpreted to mark a eustatic sea level rise that also can be recognized in Lower Permian sections in east-central Nevada and central Arizona.

  7. Detection of east/central/south African genotype of chikungunya virus in Myanmar, 2010.

    PubMed

    Tun, Mya Myat Ngwe; Thant, Kyaw Zin; Inoue, Shingo; Nabeshima, Takeshi; Aoki, Kotaro; Kyaw, Aung Kyaw; Myint, Tin; Tar, Thi; Maung, Kay Thwe Thwe; Hayasaka, Daisuke; Morita, Kouichi

    2014-08-01

    In 2010, chikungunya virus of the East Central South African genotype was isolated from 4 children in Myanmyar who had dengue-like symptoms. Phylogenetic analysis of the E1 gene revealed that the isolates were closely related to isolates from China, Thailand, and Malaysia that harbor the A226V mutation in this gene. PMID:25062511

  8. California avocados in Florida? Finding the perfect avocado for production in East-Central Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avocado (Persea americana Mill.) is a high-value fruit where most U.S. consumption is supplied using imported product. Cultivars with good fruit quality and horticultural traits may provide a useful alternative crop in east-central Florida and possibly in other locations throughout the state. A port...

  9. Detection of East/Central/South African Genotype of Chikungunya Virus in Myanmar, 2010

    PubMed Central

    Tun, Mya Myat Ngwe; Thant, Kyaw Zin; Inoue, Shingo; Nabeshima, Takeshi; Aoki, Kotaro; Kyaw, Aung Kyaw; Myint, Tin; Tar, Thi; Maung, Kay Thwe Thwe; Hayasaka, Daisuke

    2014-01-01

    In 2010, chikungunya virus of the East Central South African genotype was isolated from 4 children in Myanmyar who had dengue-like symptoms. Phylogenetic analysis of the E1 gene revealed that the isolates were closely related to isolates from China, Thailand, and Malaysia that harbor the A226V mutation in this gene. PMID:25062511

  10. Language and Area Studies: East Central and Southeastern Europe. A Survey.

    ERIC Educational Resources Information Center

    Jelavich, Charles, Ed.

    East Central and Southeastern Europe, considered as "Eastern Eruope," are the subject of a three-year survey of language and area studies undertaken by several committees of specialists of the American Council of Learned Societies. Four basic goals of the project include: (1) a survey of graduate training and research needs, (2) an evaluation of…

  11. Radioactivity at the Copper Creek copper lode prospect, Eagle district, east-central Alaska

    USGS Publications Warehouse

    Wedow, Helmuth; Tolbert, Gene Edward

    1952-01-01

    Investigation of radioactivity anomalies at the Copper Creek copper lode prospect, Eagle district, east-central Alaska, during 1949 disclosed that the radioactivity is associated with copper mineralization in highly metamorphosed sedimentary rocks. These rocks are a roof pendant in the Mesozoic "Charley River" batholith. The radioactivity is probably all due to uranium associated with bornite and malachite.

  12. Correlates of National-Level Homicide Variation in Post-Communist East-Central Europe

    ERIC Educational Resources Information Center

    Stamatel, Janet P.

    2009-01-01

    This article examines whether correlates of cross-national homicide variation tested with data from highly developed, predominantly Western nations could also explain homicide rates in East-Central Europe. Using pooled time-series analyses of data from nine countries from 1990 through 2003, this study found that homicide rates were negatively…

  13. SOIL AND HYDROLOGY OF A WET-SANDY CATENA IN EAST-CENTRAL MINNESOTA

    EPA Science Inventory

    Sail properties are strongly related to the retention and movement of water within the soil system. The purposes of this study were to document the near-surface hydrology of a wetland-upland hillslope on a sandy glacial outwash plain in east-central Minnesota and to describe the ...

  14. Pennsylvanian and Early Permian paleogeography of east-central California: Implications for the shape of the continental margin and the timing of continental truncation

    NASA Astrophysics Data System (ADS)

    Stone, Paul; Stevens, Calvin H.

    1988-04-01

    Pennsylvanian and Early Permian paleogeographic features in east-central California include a southeast-trending carbonate shelf edge and turbidite basin that we infer paralleled a segment of the western margin of the North American continent. This segment of the continental margin was oblique to an adjoining segment on the north that trended southwestward across Nevada into easternmost California. We propose that the southeast-trending segment of the margin originated by tectonic truncation of the originally longer southwest-trending segment in Early or Middle Pennsylvanian to late Early Permian time, significantly earlier than a previously hypothesized Late Permian or Early Triassic continental truncation event. We interpret the truncating structure to have been a sinistral transform fault zone along which a continental fragment was removed and carried southeastward into the Caborca-Hermosillo region of northern Mexico, where it is now represented by exposures of Late Proterozoic and Paleozoic miogeoclinal rocks.

  15. Nesting phenology and success of ring-necked ducks in east-central Maine

    USGS Publications Warehouse

    McAuley, D.G.; Longcore, J.R.

    1989-01-01

    Selected aspects of the nesting biology of Ring-necked Ducks in east-central Maine were studied during 1983-1985 and compared to previous studies. Nesting chronology, clutch size, and hatching success were similar to results reported from previous studies, but nest success was 32-42% lower. Thirty-eight percent of the nests were successful; % of the eggs in successful nests hatched. Among unsuccessful nests, predation and flooding caused most failures.

  16. Depositional environments of Late Triassic lake, east-central New Mexico

    SciTech Connect

    Hester, P.M. )

    1989-09-01

    The Redonda Member of the Chinle Formation represents deposition in a large, polymictic lake during the Late Triassic (Norian) in east-central New Mexico. This study documents and defines an extensive lacustrine system situated in western Pangaea which was influenced by both tectonic and climatic events. Areal extent of the lake may have been as much as 5,000 km{sup 2}.

  17. NO{sub x} controls for coal-fired utility boilers in East Central Europe

    SciTech Connect

    Eskinazi, D.; Tavoulareas, E.S.

    1995-12-01

    Increasing environmental pressures worldwide, including East Central Europe are placing greater emphasis on NO{sub x} emission controls in utility power plants. Western Europe, Japan and the U.S. have significant experience in applying NO{sub x} controls, especially in boilers firing hard coal. Some countries in Europe (i.e., Germany and Austria), have gained experience in applying NO{sub x} controls in boilers firing low-rank coal. This experience can be applied to East Central European countries in providing the basis for planning NO{sub x} control projects, suggesting cost-effective solutions, and providing lessons learned. However, while the experience is generally applicable to East Central European countries, differences in boiler design, operation and coal characteristics also need to be considered. This paper begins with a comparison of the NO{sub x} regulations, identifies the key NO{sub x} control technologies and the worldwide experience with them, and discusses the achievable NO{sub x} reduction, O&M impacts, and retrofit costs for each technology. Emphasis is placed on retrofit applications for existing boilers, because new coal-fired power plants are not expected to be built for the next 5-10 years. This paper also focuses on technologies with relatively low cost and operational simplicity: combustion system tuning/optimization. low-NO{sub x} burners (LNB), overfire air (OFA), selective non-catalytic reduction (SNCR), and reburning.

  18. General circulation model simulations of recent cooling in the east-central United States

    NASA Astrophysics Data System (ADS)

    Robinson, Walter A.; Reudy, Reto; Hansen, James E.

    2002-12-01

    In ensembles of retrospective general circulation model (GCM) simulations, surface temperatures in the east-central United States cool between 1951 and 1997. This cooling, which is broadly consistent with observed surface temperatures, is present in GCM experiments driven by observed time varying sea-surface temperatures (SSTs) in the tropical Pacific, whether or not increasing greenhouse gases and other time varying climate forcings are included. Here we focus on ensembles with fixed radiative forcing and with observed varying SST in different regions. In these experiments the trend and variability in east-central U.S. surface temperatures are tied to tropical Pacific SSTs. Warm tropical Pacific SSTs cool U.S. temperatures by diminishing solar heating through an increase in cloud cover. These associations are embedded within a year-round response to warm tropical Pacific SST that features tropospheric warming throughout the tropics and regions of tropospheric cooling in midlatitudes. Precipitable water vapor over the Gulf of Mexico and the Caribbean and the tropospheric thermal gradient across the Gulf Coast of the United States increase when the tropical Pacific is warm. In observations, recent warming in the tropical Pacific is also associated with increased precipitable water over the southeast United States. The observed cooling in the east-central United States, relative to the rest of the globe, is accompanied by increased cloud cover, though year-to-year variations in cloud cover, U.S. surface temperatures, and tropical Pacific SST are less tightly coupled in observations than in the GCM.

  19. Mantle dynamics and Cretaceous magmatism in east-central China: Insight from teleseismic tomograms

    NASA Astrophysics Data System (ADS)

    Jiang, Guoming; Zhang, Guibin; Zhao, Dapeng; Lü, Qingtian; Li, Hongyi; Li, Xinfu

    2015-11-01

    Both the rich mineralization in the Lower Yangtze Block (LYB) and the post-collisional mafic rocks in the Dabie Orogen (DBO) are closely related to the Cretaceous magmatism in east-central China. Various geodynamic models have been proposed for explaining the mechanism of the Cretaceous magmatism, but these models are controversial and even contradictory with each other, especially on the mechanism of adakites. A unified geodynamic model is required for explaining the magmatism in east-central China, in particular, the spatial and temporal correlations of magmatic activity in the DBO and that in the LYB. For this purpose, we apply teleseismic tomography to study P-wave velocity structure down to 800 km depth beneath east-central China. A modified multiple-channel cross-correlation method is used to collect 28,805 high-quality P-wave arrival-time data from seismograms of distant earthquakes recorded by permanent seismic stations and our temporary stations in the study region. To remove the influence of crustal heterogeneity on the mantle tomography, we used the CRUST1.0 model to correct the teleseismic relative residuals. Our tomography revealed distinct high-velocity (high-V) anomalies beneath the DBO and two flanks of the LYB, and low-velocity (low-V) anomalies above the high-V zones. Combining our tomographic images with previous geological, geochemical and geophysical results, we infer that these high-V and low-V anomalies reflect the detached lithosphere and upwelling asthenospheric materials, respectively, which are associated with the Late Mesozoic dynamic process and the Cretaceous magmatism. We propose a double-slab subduction model that a ridge subduction yielded the adakitic rocks in the LYB during 150-135 Ma and the subsequent Pacific Plate subduction played a crucial role in not only the formation of igneous rocks in the LYB but also remelting of the subducted South China Block beneath the DBO during 135-101 Ma.

  20. A historical perspective of the extremely hot 2013 summer in East-central China

    NASA Astrophysics Data System (ADS)

    Liu, Qi; Fu, Congbin; Mao, Huiting

    2016-04-01

    An extreme hot summer occurred over East-central China in 2013. Its duration of continuous, highest temperature anomalies was the longest on record for the time period of 1948-2013. Several modeling studies have attempted to identify the causes and did not obtain conclusive findings, in large part due to their limited scopes of the problem. Here, we conducted a multi-scale and multi-factor analysis of this extreme event using observational data of 600 monitoring stations over China and global reanalysis data for the period of 1981-2013. Our results suggested that the number of heatwave days (NHD) (defined as a day with daily maximum temperature ≥ 35°C) over East-central China experienced an increasing trend of 3.44 days per decade since 1981 and reached the record maximum (34.1 days) in 2013, with significant inter-annual variability superimposed on the trend. It should be noted that this increasing trend in NHD was consistent with that of the intensity of the Western Pacific Subtropical High (WPSH) linked to global warming as suggested in the literature. There were also strong correlations between NHD over East-central China, WPSH, and global mean temperature (GT) on interannual scales. The extremely hot 2013 summer could not be explained by global warming and associated enhanced WPSH alone as GT and WPSH intensity were not record high in that summer. Further analysis suggested that large scale air-sea interaction over the Pacific region could have played a critical role. Specifically, enhanced convection over the Philippine Sea and along Indonesian islands in summer 2013 appeared to be strongest for the study period. This convection could cause a strong local feedback among precipitation, cloud cover, and net radiation, which could further weaken upper- and lower-level circulation via the tropical-extratropical teleconnection and Rossby wave propagation. This feedback was likely the direct cause of the extremely hot 2013 summer.

  1. Evidence for Early Pleistocene Glaciation obtained from borecores collected in East-Central Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Barendregt, R. W.; Andriashek, L. D.; Jackson, L. E.

    2014-12-01

    Borecores collected from the east-central region of Alberta, Canada have recently been sub-sampled and studied for paleomagnetic remanence characteristics. A preliminary magnetostratigraphy has been established for sediments previously assumed to represent multiple continental (Laurentide) glaciations, but for which no geochronology was available for the pre-late Wisconsin units. Comprised primarily of tills and lesser thicknesses of interbedded glacio-lacustrine and outwash sediments, the record is extensive, reaching to thicknesses of 300 metres within buried valleys. Most of the sampled units are not accessible from outcrop, and their sedimentology and stratigraphy is derived from core data only. The lowermost tills are reversely magnetized in the majority of borecores sampled to date. These tills are underlain by Empress Formation sediments and/or Colorado Group shales, and overlain by normally magnetized sediments. Both tills contain substantial weathering horizons at their surface, suggesting that interglacial or nonglacial conditions persisted for some time after each period of till deposition. Whether these tills represent a single Early Pleistocene glaciation, or perhaps two, will require additional borecore measurements. This new record of Early Pleistocene glaciation(s) in east-central Alberta places the westernmost extent of earliest Laurentide ice some 300 km farther westward from its previously established limit in the Saskatoon to Regina region of the western Canadian prairies, but still well short of the all-time limit and elevation reached during the Late Wisconsin (Late Pleistocene) in the foothills of the Alberta and Montana Rocky Mountains. Key Words: East-Central Alberta glacial history, Early Pleistocene (Laurentide) glaciation, till magnetostratigraphy, Quaternary history of Western Canadian Prairies, continental glaciations of North America.

  2. Selected hydrologic data for Fountain Creek and Monument Creek basins, east-central Colorado

    USGS Publications Warehouse

    Kuhn, Gerhard; Ortiz, Roderick F.

    1989-01-01

    Selected hydrologic data were collected during 1986, 1987, and 1988 by the U.S. Geological Survey for the Fountain Creek and Monument Creek basins, east-central Colorado. The data were obtained as part of a study to determine the present and projected effects of wastewater discharges on the two creeks. The data, which are available for 129 surface-water sites, include: (1) About 1,100 water quality analyses; (2) about 420 measurements of discharge, (3) characteristics of about 50 dye clouds associated with measurements of traveltime and reaeration , and (4) about 360 measurements of channel geometry. (USGS)

  3. Penokean tectonics along a promontory-embayment margin in east-central Minnesota

    USGS Publications Warehouse

    Chandler, V.W.; Boerboom, Terrence; Jirsa, M.A.

    2007-01-01

    Recent geologic investigations in east-central Minnesota have utilized geophysical data, test drilling, and high-resolution geochronologic dating to produce a significantly improved map of a poorly exposed part of the 1880-1830 Ma Penokean orogen. These investigations have elucidated major changes in the structure of the orogen, as compared to its counterparts in northern Michigan and northwestern Wisconsin. Foreland basin, fold and thrust belt, and magmatic terrane components that are recognized to the east extend into east-central Minnesota, but they appear to be deflected southwards and truncated in proximity to Archean rocks of the Minnesota River Valley (MRV) subprovince. In contrast, the interior of the MRV subprovince to the southwest shows little sign of Penokean tectonism. In addition, the magmatic and metamorphic rocks of the internal zone of the orogen in east-central Minnesota are extensively invaded by ca. 1785-1770 Ma granitic rocks (the East-Central Minnesota Batholith), whereas, post-orogenic granites of this age occur sparingly to the east. These differences in orogenic structure may be related to their location near the juncture of an embayment (Becker embayment) and a promontory (MRV promontory) that formed the pre-Penokean continental margin. In this scenario, the MRV promontory, which at the surface consists chiefly of high-metamorphic-grade Mesoarchean gneisses, would have formed competent, high-standing crust that resisted deformation and did not host significantly thick continental margin sequences. In contrast, the part of the Becker Embayment adjoining the promontory would have involved relatively weak, low-standing crust that favored deposition of continental margin sequences and, during Penokean collision, would have accommodated tectonic loading of the cratonic margin through thin-skinned deformation. Thrusting of thick embayment sequences and possibly a block of Archean crust (Marshfield terrane) onto the embayment margin may have

  4. The Cretaceous record in a northeast-trending transect, northern Utah to east-central Wyoming

    SciTech Connect

    Merewether, E.A. )

    1991-03-01

    Cretaceous sedimentary rocks in the Laramide basins of the middle Rocky Mountains include 16,600 ft (5060 m) of predominantly siliciclastic strata in the thrust-belt of northern Utah and 7800 ft (2380 m) of mainly siliciclastic and calcareous strata near the craton in east central Wyoming. Regional changes in the thickness of the strata indicate that crustal subsidence during the Cretaceous was generally greatest in northern Utah and western Wyoming where it was associated with tectonic and sediment loading. However, the considerable thickness of uppermost Cretaceous nonmarine beds in several other areas reflects pronounced basin subsidence during early stages of the Laramide orogeny. In a transect from northern Utah to east-central Wyoming, based on outcrop sections, borehole logs, and chronostratigraphic data, Cretaceous rocks grade northeastward from mainly fluvial and nearshore marine synorogenic conglomerate, sandstone, mudstone, coal, and bentonite to mostly nearshore and offshore marine sandstone, mudstone, calcareous shale, and bentonite. Lateral changes in the lithofacies and in the extent of enclosed unconformities indicate marine transgressions and regressions that were effected by structural deformation, sedimentation, and eustatic events. Significant unconformities have been found at the base of the Cretaceous strata, at two horizons within beds of Albian age, at two horizons within rocks of Cenomanian and Turonian ages, at one horizon within Coniacian strata, and at two horizons within Campanian beds. Most of these unconformities are either flooding surfaces or sequence boundaries.

  5. Ordovician sponges from west-central and east-central Alaska and western Yukon Territory, Canada

    USGS Publications Warehouse

    Rigby, J.K.; Blodgett, R.B.; Britt, B.B.

    2008-01-01

    Moderate collections of fossil sponges have been recovered over a several-year period from a few scattered localities in west-central and east-central Alaska, and from westernmost Yukon Territory of Canada. Two fragments of the demosponge agelasiid cliefdenellid, Cliefdenella alaskaensis Stock, 1981, and mostly small unidentifiable additional fragments were recovered from a limestone debris flow bed in the White Mountain area, McGrath A-4 Quadrangle in west-central Alaska. Fragments of the agelasiid actinomorph girtyocoeliids Girtyocoeliana epiporata (Rigby & Potter, 1986) and Girtyocoelia minima n. sp., plus a specimen of the vaceletid colospongiid Corymbospongia amplia Rigby, Karl, Blodgett & Baichtal, 2005, were collected from probable Ashgillian age beds in the Livengood B-5 Quadrangle in east-central Alaska. A more extensive suite of corymbospongiids, including Corymbospongia betella Rigby, Potter & Blodgett, 1988, C. mica Rigby & Potter, 1986, and C.(?) perforata Rigby & Potter, 1986, along with the vaceletiid colospongiids Pseudo-imperatoria minima? (Rigby & Potter, 1986), and Pseudoimperatoria media (Rigby & Potter, 1986), and with the heteractinid Nucha naucum? Pickett & Jell, 1983, were recovered from uppermost part of the Jones Ridge Limestone (Ashgillian), on the south flank of Jones Ridge, in the Sheep Mountain Quadrangle, in westernmost Yukon Territory, Canada. The fossil sponges from the McGrath A-4 and Livengood B-5 quadrangles were recovered from attached Siberian terranes, and those from the Sheep Mountain Quadrangle were recovered from an allochthonous Laurentian terrane in the Yukon Territory.

  6. Oaks were the historical foundation genus of the east-central United States

    NASA Astrophysics Data System (ADS)

    Hanberry, Brice B.; Nowacki, Gregory J.

    2016-08-01

    Foundation tree species are dominant and define ecosystems. Because of the historical importance of oaks (Quercus) in east-central United States, it was unlikely that oak associates, such as pines (Pinus), hickories (Carya) and chestnut (Castanea), rose to this status. We used 46 historical tree studies or databases (ca. 1620-1900) covering 28 states, 1.7 million trees, and 50% of the area of the eastern United States to examine importance of oaks compared to pines, hickories, and chestnuts. Oak was the most abundant genus, ranging from 40% to 70% of total tree composition at the ecological province scale and generally increasing in dominance from east to west across this area. Pines, hickories, and chestnuts were co-dominant (ratio of oak composition to other genera of <2) in no more than five of 70 ecological subsections and two of 20 ecological sections in east-central United States, and thus by definition, were not foundational. Although other genera may be called foundational because of localized abundance or perceptions resulting from inherited viewpoints, they decline from consideration when compared to overwhelming oak abundance across this spatial extent. The open structure and high-light conditions of oak ecosystems uniquely supported species-rich understories. Loss of oak as a foundation genus has occurred with loss of open forest ecosystems at landscape scales.

  7. The main characteristics of atmospheric circulation over East-Central Europe from 1871 to 2010

    NASA Astrophysics Data System (ADS)

    Bartoszek, Krzysztof

    2016-05-01

    The main objective of the paper concerns the determination of the annual and multi-annual variability of air flow over East-Central Europe in the period 1871-2010. Daily mean sea-level pressure and values of physical quantities provided the basis for distinguishing 27 circulation types, i.e., eight directional cyclonic, transitional, and anticyclonic types, and one non-directional cyclonic, anticyclonic, and an undefined type. Over the area of East-Central Europe, the highest frequency is recorded for air flow from the western sector, with a maximum in the period from December to January. In spring, a higher than average frequency of cyclonic and easterly circulation is observed, and in summer—anticyclonic and northerly. Increased zonal circulation was recorded in the years 1910-1930, and particularly after 1970, and eastern at the end of the nineteenth century and in the 1930s and 1940s. An increase in the frequency of days with non-directional anticyclonic type and westerly air flow, and a simultaneous decrease in frequency of days with south-easterly and easterly circulation were observed throughout the study period. Among the three classes of circulation types, the highest persistence (particularly in winter) was recorded for anticyclonic types, i.e., when the high pressure system occurred over the Scandinavian Peninsula or East Europe.

  8. Lesser scaup winter foraging and nutrient reserve acquisition in east-central Florida

    USGS Publications Warehouse

    Herring, G.; Collazo, J.A.

    2006-01-01

    Lesser scaup (Aythya affinis) populations have been declining since the late 1970s. One of the explanations to account for this decline, the spring-condition hypothesis (SCH), is based on the premise that scaup are limited by their ability to acquire or maintain nutrient reserves during migration to the breeding grounds, leading to an impairment of their reproductive potential. Available evidence suggests that endogenous reserves required for reproduction are obtained at a later stage of migration or after arrival at the breeding grounds, not wintering sites. However, only one study has addressed body-condition levels on a southern wintering site in the last decade, with results limited to the wintering grounds on the Mississippi Flyway. We documented foraging behavior, nutrient levels, and body mass of lesser scaup in east-central Florida, USA, where 62% of the Atlantic Flyway population overwinters, during the winters of 2002 and 2003. Diurnal foraging did not increase seasonally. Nocturnal foraging increased seasonally by 76% or 43 minutes per night in females and by 478% or 1.9 hours per night in males. Measures of body condition did not change seasonally during 2002 for either sex. Between early and later winter in 2003 corrected body mass (CBM) and lipid reserves of male scaup increased 77 g and 39 g, respectively. Our results suggest that lesser scaup maintain or may slightly improve their physiological condition in east-central Florida during winter. Lower body mass and differences in nutrient levels in east-central Florida, compared to a wintering site in Louisiana, likely stem from geographic variation and lower thermal requirements associated with the warmer Florida environment. Lesser scaup depart Florida with sufficient reserves to initiate spring migration, but they maximize nutrient reserves used during reproduction elsewhere during migration or on the breeding grounds. These results suggest that maintaining the ecological integrity of this wintering

  9. Structural relationships of pre-Tertiary rocks in the Nevada Test Site region, southern Nevada

    SciTech Connect

    Cashman, P.H.; Cole, J.C.

    1999-08-30

    This report summarizes the evidence for a revised interpretation of major structural features in the pre-Tertiary rocks of the region including and surrounding the Nevada Test Site. The thick miogeoclinal section of Late Proterozoic through Lower Permian sedimentary strata records major foreland-vergent thrust faulting, younger hinterland-vergent folding and thrusting, and local extension on low-angle normal faults. In addition, structural discontinuities in the northeastern part of the Nevada Test Site strongly suggest a broad, north-trending zone of sinistral strike-slip faulting that may have had a cumulative offset of many kilometers.

  10. Kinematic stratification in the hinterland of the central Scandinavian Caledonides

    USGS Publications Warehouse

    Gilotti, J.A.; Hull, J.M.

    1993-01-01

    A transect through west-central Norway illustrates the changing geometry and kinematics of collision in the hinterland of the central Scandinavian Caledonides. A depth section through the crust is exposed on Fosen Peninsula, comprising three tectonic units separated by two shear zones. The lowest unit, exposed in the Roan window, is a modestly deformed, Caledonian granulite complex framed by a subhorizontal de??collement, with NW-SE oriented lineations and kinematic indicators showing top-to-the-northwest transport. The middle unit, the Vestranden gneiss complex, contains relict granulites, but was penetratively deformed at amphibolite facies to produce an orogen-parallel family of structures during translation on the de??collement. Shallow plunging lineations on steep schistosities are subparallel to fold axes of the dominant, upright, non-cylindrical folds. A small component of sinistral strike slip is also recorded. In contrast, southernmost Fosen Peninsula contains an abundance of cover rocks infolded with Proterozoic basement in a fold nappe, with shallow, E-dipping schistosities, down-dip lineations, and orogen-oblique, top-to-the-west shear sense indicators. A NE-striking, sinistral shear zone separates the gneisses from southern Fosen. Deformation in the Scandian hinterland was partitioned both in space and time, with orogen-parallel extension and shear at middle structural levels and orogen-oblique transport at shallower levels. ?? 1993.

  11. Manganese resources of the Cuyuna range, east-central Minnesota. Report of Investigations 24

    SciTech Connect

    Beltrame, R.J.; Holtzman, R.C.; Wahl, T.E.

    1981-01-01

    The Cuyuna range, located in east-central Minnesota, consists of a sequence of argillite, siltstone, iron-formation, graywacke, slate, and quartzite of early Proterozoic age. Manganese-bearing materials occur within the iron-rich strata of the Trommald Formation and the Rabbit Lake Formation. Computer-assisted resource estimates, based on exploration drill hole information, indicate that the Cuyuna range contains a minimum of 176 million metric tons (MMT) of marginally economic manganiferous rock with an average grade of 10.46 weight percent manganese. The calculated 18.5 MMT of manganese on the Cuyuna range could supply this country's needs for this important and strategic metal for nearly 14 years. An additional resource of 6.9 MMT of manganese metal is available in the lower grade deposits. The vast majority of these calculated resources are extractable by current surface mining techniques.

  12. Gold deposit styles and placer gold characterisation in northern and east-central Madagascar

    USGS Publications Warehouse

    Pitfield, Peter E. J; Styles, Michael T.; Taylor, Cliff D.; Key, Roger M.; Bauer, Wilfried; Ralison, A, Vonimanitra

    2009-01-01

    Microchemical characterisation of bedrock and placer gold grains from six gold districts within the Archaean domains and intervening Neoproterozoic Anaboriana-Manampotsy belt of northern and east-central Madagascar show few opaque inclusions (e.g pyrrhotite, Bi tellurides) but wide range of Ag contents (40wt%). Some districts exhibit multiple source populations of grains. The ‘greenstone belt’ terranes have an orogenic gold signature locally with an intrusion-related to epithermal overprint. Proterozoic metasediments with felsic to ultramafic bodies yield dominantly intrusion-related gold. A high proportion of secondary gold (<0.5wt% Ag) is related to recycling of paleoplacers and erosion of post-Gondwana planation surfaces and indicates that some mesothermal gold systems were already partially to wholly removed by erosion by the PermoTriassic.

  13. Water quality of a reservoir and its major tributary located in east-central Mexico.

    PubMed

    Castilla-Hernández, Patricia; del Rocío Torres-Alvarado, María; Herrera-San Luis, José Antonio; Cruz-López, Norma

    2014-06-01

    A reservoir with ecological and economic importance and its major tributary, localized in east-central Mexico, were studied. The aim of this work was to know the physicochemical water characteristics of both water bodies and to contrast these by their different uses, and also estimate overall water quality using a Water Quality Index (WQI). Water samples from the reservoir and the tributary were obtained in different climatic seasons. In the tributary, anoxic and hypoxic conditions and high levels of organic matter, orthophosphate, and ammonium showed that this is strongly impacted by wastewater discharges and that the water is not suitable for different uses; independently of the season, the WQI showed "poor" quality (34.4-47.2). In contrast, in the reservoir a better water quality was determined; the WQI in the sampling months ranged from 72.1-76.6 ("good" quality), and spatially, this was from 66.5-79.5 ("fair" and "good" quality). PMID:24919132

  14. Investigation of rainfall data with regard to low-level wind flow regime for east central Florida

    NASA Technical Reports Server (NTRS)

    Brooks, Joni

    1992-01-01

    Previous research has been conducted to investigate the effect of the low-level wind region on summertime convective storms in the east central Florida area. These effects were described by analyzing the distribution of lightning flashes within classifications based on the low-level wind regime for the months June through September of 1987 to 1990. The present research utilizes the same classification strategy to study rainfall patterns for data gathered for the CaPE (Convection and Precipitation/Electrification Experiment) field program. The CaPE field program was conducted in east central Florida from July 8, 1991 to August 18, 1991.

  15. Emergence of Thelazia callipaeda Infection in Dogs and Cats from East-Central Portugal.

    PubMed

    Maia, C; Catarino, A L; Almeida, B; Ramos, C; Campino, L; Cardoso, L

    2016-08-01

    The eyeworm Thelazia callipaeda (Spirurida, Thelaziidae) infects domestic animals, wildlife and human beings, and is considered an emerging pathogen in Europe. This study aimed at investigating the prevalence and risk factors of T. callipaeda infection in dogs and cats from east-central Portugal, a region where the parasite was previously detected in two red foxes (Vulpes vulpes). Thelazia callipaeda was found in 22 (3.8%) of 586 dogs and in four (23.5%) of 17 cats. A total of 178 adult worms (71.9% of females and 28.1% of males) were collected from the conjunctiva of the infected dogs. The number of worms collected per dog ranged from 1 to 35 (average ± standard deviation: 8.08 ± 9.49), with four dogs (18.2%) harbouring only a single parasite. Worms were gathered from dogs throughout all months of the year. A total of 17 adult worms (64.7% of females and 35.3% of males) were obtained from cats. The number of worms per cat ranged from 1 to 14 (4.3 ± 6.5), with three cats (75.0%) having a single parasite. Eyeworm infection was statistically more prevalent in pastoral and farm dogs, in those dogs with contact with other animals and in dogs with ocular manifestations. T. callipaeda is endemic in the east-central part of Portugal, reportedly infecting domestic (dogs and cats) and wild carnivores (red foxes) and evidencing a southerly dissemination. Future investigations should be focused on determining the local distribution and density of the insect vector (Phortica variegata) in this geographical area. This emergent zoonosis should be included by veterinarians, physicians and ophthalmologists in the differential diagnosis of ocular manifestations in their patients, particularly in areas where T. callipaeda is endemic. PMID:25382165

  16. West Nile virus infection rates and avian serology in east-central Illinois.

    PubMed

    Lampman, Richard L; Krasavin, Nina M; Ward, Mike P; Beveroth, Tara A; Lankau, Emily W; Alto, Barry W; Muturi, Ephantus; Novak, Robert J

    2013-06-01

    Understanding the geographic role of different species of mosquito vectors and vertebrate hosts in West Nile virus (WNV) transmission cycles can facilitate the development and implementation of targeted surveillance and control measures. This study examined the relationship between WNV-antibody rates in birds and mosquito infection rates and bloodfeeding patterns in east-central Illinois. The earliest detection of WNV-RNA by reverse transcription-polymerase chain reaction TaqMan was from Culex restuans; however, amplification typically coincided with an increase in abundance of Cx. pipiens. Trap type influenced annual estimates of infection rates in Culex species, as well as estimation of blood meal source. Bird species with the highest WNV-antibody rates (i.e., Mourning Doves [Zenaida macroura], Northern Cardinals [Cardinalis cardinalis], American Robins [Turdus migratorius], and House Sparrows [Passer domesticus]) were also the common species found in Culex blood meals. Although antibody rates were not directly proportional to estimated avian abundance, the apparent availability of mammal species did influence proportion of mammal to bird blood meals. Antibody prevalence in the American Robin was lower than expected based on the strong attraction of Culex to American Robins for blood meals. Age-related differences in serology were evident, antibody rates increased in older groups of robins and sparrows, whereas 1st-year hatch and older adults of Mourning Doves and Northern Cardinals had equally high rates of antibody-positive serum samples. The vector and host interactions observed in east-central Illinois (Champaign County), an urban area surrounded by agriculture, are compared to studies in the densely population areas of southern Cook County. PMID:23923325

  17. Rise and Demise of a Southern Laramide Hinterland Plateau, US-Mexico Border Region

    NASA Astrophysics Data System (ADS)

    Lawton, T. F.; Clinkscales, C. A.; Jennings, G. R.

    2011-12-01

    -west normal faults are occupied by regionally widespread granitic and rhyolitic dikes ranging 34-27 Ma, yet the Oligocene volcaniclastic rocks are cut by the faults, indicating that the fault system was active during earliest-early late Oligocene magmatism. From the newly assembled data, we infer the presence of a high-standing plateau along the US-Mexico border that was backed by a magmatic arc in northern Mexico. The plateau was supported by lithosphere thickened during backarc contraction, which began in the interval 97-75 Ma. Although the depositional elevation of the Laramide lakes is not yet known, rivers flowed northward from the hinterland plateau toward the Uinta Basin as early as 80 Ma and corroborate the existence of a southern source area. The plateau was thus a long-lived feature with a longevity of as much as 40-50 m.y. It collapsed during Paleogene N-S extension triggered by some combination of thermal weakening by Oligocene magmatism, gravitational failure, and/or retrograde motion of the Farallon slab. The southern Laramide plateau was evidently linked both geographically and temporally to the Cordilleran hinterland plateau ("Nevadaplano") of Nevada and western Utah and thus constituted an important component of the greater Laramide orogen.

  18. Relation between extensional geometry of the northern Grant Range and oil occurrences in railroad valley, East-Central Nevada

    SciTech Connect

    Lund, K.; Perry, W.J. Jr. ); Beard, L.S. )

    1993-06-01

    In the northern Grant Range, heterogeneous Neogene extension was dominated by synchronous arching and attenuation. Attenuation was accomplished along a stacked set of attenuation faults that formed at low angles to bedding as the Paleozoic carbonate and Paleogene rocks arched about a north-northwest axis. The style and amount of attenuation was controlled by lithologic character and structural depth of rock units and by geometry of the arch. On the steeper west side of the Grant Range arch, the curviplanar low-angle attenuation faults converge into a single shallowly west-dipping fault zone along which the stratigraphic juxtaposition of Mississippian units over Middle Cambrian units and Late Cretaceous granite marks the zone of maximum attenuation. Arching and heterogeneous extension resulted from uplift of the Grant Range relative to the structural basin of Railroad Valley to the west. This structural differentiation is a complex zone of subparallel-to-bedding, shallow-dipping attenuation faults rather than as a simple high-angle range-front fault. Seismic and drill-hole data indicate that low-angle attenuation faults in the range extend into Railroad Valley and control the structure buried in the valley. Mississippian and Paleocene to Eocene petroleum source rocks and Devonian to Oligocene reservoir rocks in Railroad Valley oil fields are in extensively fractured rocks of the upper plate to the major extensional fault system. Thus, relatively cold upper-plate rocks, immature with respect to hydrocarbon generation, were brought relatively down into contact with hotter lower-plate rocks by Neogene attenuation faulting. Oil in Railroad Valley, which is sourced from rocks as young as Eocene, was probably generated by this juxtaposition during Neogene crustal attenuation, and subsequently migrated into upper-plate fractured reservoirs. 101 refs., 10 figs.

  19. Apatite fission track evidence for Miocene extensional faulting east-central Nevada, northern Basin and Range province

    SciTech Connect

    Miller, E.L.; Dumitru, T.A. . Geology Dept.); Gans, P.B. . Geological Sciences Dept.); Brown, R.W. . Geology Dept.)

    1993-04-01

    Apatite fission track ages indicates that a large component of motion along many of the present range-bounding faults occurred in the Early to Middle Miocene, tilting and uplifting rocks through the apatite annealing zone (120--60 C) between 18--13 Ma (n = 20, Deep Creeks), 18--15 Ma (northern Snake Range, n = 20), 25--17 Ma (n = 7, southern Snake Range), 24--15 Ma (Egan Range, n = 6), 23--18 Ma (Kern Mts., n = 2) and 28--16 ma (Schell Creek Range, n = 2). Long track length distributions indicate rapid cooling through the 120--60 C interval followed by residence at low, near surface temperatures. The data set also indicates that the combined Deep Creek-Kern Mountains-northern and southern Snake Range constitutes a single coherent footwall crustal block beneath a > 150 km-long system of east-dipping Miocene faults which includes at least the eastern portions of faults that have been mapped as the Snake Range decollement (NSRD). Conglomerates deposited in hanging wall basins along this fault system contain metamorphic and granitic boulders whose FT ages are coeval with footwall unroofing. The deposits themselves are now known to be younger than previously reported (Oligocene) as ages from boulders are Miocene. The thick (> 2 km) sequences of synorogenic conglomerate indicates rapid unroofing; large slide blocks attest to generation of steep, fault-controlled topography. Faults that cut this sequence are now known to be younger than 15 Ma. Thus, protracted extensional faulting affected the region, beginning in the Early Oligocene and continuing to the Recent, but a significant part of this extension, including a large component of the slip on the NSRD, was accomplished in the Early to Middle Miocene. Data from this region is compatible with a growing base of apatite fission track data from elsewhere in the northern Basin and Range, which, together with geologic relationships, suggest an important episode of Miocene extension and Basin and Range development.

  20. Crooked Calf Syndrome: Managing Lupines on Rangelands of the Channel Scablands of East-Central Washington State

    Technology Transfer Automated Retrieval System (TEKTRAN)

    “Crooked calf syndrome”, the contracture-type skeletal defects and cleft palate caused by velvet lupine (Lupinus leucophyllus) on the channel Scablands of east-central Washington State are the same as those defects induced by Conium maculatum (poison-hemlock) and Nicotiana spp. (wild tobacco) in rum...

  1. Factors and Perceptions that Affect Enrollment in Career and Technical Education Programs in Rural East Central Mississippi

    ERIC Educational Resources Information Center

    Brown, Aimee Chandler

    2009-01-01

    The primary purpose of this study was to determine the factors and perceptions that affect enrollment in career and technical education (CTE) programs in rural East Central Mississippi. Specifically, the study had four key purposes. First, the academic grades of CTE students and non-CTE students were examined to determine whether academic grades…

  2. Populations of sharpshooters in two citrus groves in east-central Florida as indicated by yellow sticky card traps

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three sharpshooter species were captured on yellow sticky card traps in two citrus groves in east-central Florida: Homalodisca insolita, H. vitripennis and Oncometopia nigricans. H. vitripennis and O. nigricans were relatively common and H. vitripennis relatively abundant over a three year period ...

  3. Comparison of recharge estimates at a small watershed in east-central Pennsylvania, USA

    USGS Publications Warehouse

    Risser, D.W.; Gburek, W.J.; Folmar, G.J.

    2009-01-01

    The common recommendation that recharge should be estimated from multiple methods is sound, but the inherent differences of the methods make it difficult to assess the accuracy of differing results. In this study, four methods for estimating groundwater recharge and two methods for estimating base flow (as a proxy for recharge) are compared at two hydrologic research sites in east-central Pennsylvania, USA. Results from the multiple methods all provided reasonable estimates of groundwater recharge that differed considerably. The estimates of mean annual recharge for the period 1994-2001 ranged from 22.9 to 35.7 cm - about 45% of the mean of all estimates. For individual years, recharge estimates from the multiple methods ranged from 30 to 42% of the mean value during the dry years and 64 to 76% of the mean value during wet years. Comparison of multiple methods was found to be useful for determining the range of plausible recharge rates and highlighting the uncertainty of the estimates. ?? US Government 2008.

  4. Y chromosome STR allelic and haplotype diversity in a Rwanda population from East Central Africa.

    PubMed

    Balamurugan, Kuppareddi; Duncan, George

    2012-03-01

    We have analyzed 17 Y-chromosomal STR loci in a population sample of 69 unrelated male individuals of the Rwanda-Hutu population from East Central Africa using an AmpFlSTR® Yfiler™ PCR amplification kit. A total of 62 unique haplotypes were identified among the 69 individuals studied. The haplotype diversity was found to be 0.9970 for this population. The gene diversity ranged from 0.1130 (DYS392) to 0.7722 (DYS385). Comparison of populations in this study with twenty-five other national and global populations using Principal Co-ordinate Analysis (PCA) and phylogenetic molecular analysis using a genetic distance matrix indicates a delineation of all the African populations from other unrelated populations. The results of population pair-wise Fst p values indicate statistically significant differentiation of the Rwandan population when compared with 25 other global populations including four African populations (p=0.0000). Analysis of Molecular Variance (AMOVA) of the Rwanda population with four other African populations indicated a 93% variance within populations and 7% variance among the five populations. A data base search of the 62 haplotypes yielded only one non-African haplotype match, suggesting these haplotypes are unique to the African continent. PMID:22285642

  5. Anomalous folds associated with the east-central part of the Garlock Fault, southeast California

    USGS Publications Warehouse

    Smith, G.I.

    1991-01-01

    The east-central part of the left-lateral Garlock Fault, in southeast California, is associated with three broad folds that trend and plunge northeast. The folds, which lie north, south, and astride the fault, postdate deposition of alluvial gravels that at one time formed a continuous northwest-sloping fan. Corrected tilting rates vary from about 2.5?? to 4.7??/m.y.; the total shortening of about 7.5 m developed at a minimum rate of 12.5 m/m.y. The orientations of these folds imply northwest-southeast compression, which is anomalous when viewed in the context of regional tectonics. These anomalous features are interpreted as evidence that episodes of NW-SE compression along the Garlock Fault do occur, and although oriented about 90?? from the average of conventional - and presently observed - compression directions, they have occurred during much (most?) of the Cenozoic Era, including the past 0.6 m.y. -from Author

  6. What's up, Billy Jo? Deaf children and bilingual-bicultural instruction in east-central Texas.

    PubMed

    Andrews, J F; Ferguson, C; Roberts, S; Hodges, P

    1997-03-01

    Seven deaf children attended a bilingual-bicultural (bi-bi) prekindergarten, kindergarten, and first grade from 1993 to 1996 in an east-central Texas public school. The children had diverse backgrounds (African American, Hispanic, White) and various intellectual, cognitive, and linguistic abilities. We detail the backgrounds of the seven children and their families and describe three bi-bi classrooms. We present standardized test scores on cognition (Bracken Test of Basic Concepts) and academic achievement (Stanford Achievement Test, 9th edition, and Woodcock-Johnson Psycho-Educational Battery). When, with one exception, the children completed first grade, they all tested at grade level. (The exception was a younger child who had only completed kindergarten but who nonetheless tested at the first-grade level). We interpret our findings in light of theories of first- and second-language acquisition and discuss the feasibility of establishing bi-bi programs in areas where no large Deaf community exists. We also note our plans to evaluate the seven children again, at the end of second grade in spring 1997. PMID:9127497

  7. Magnetic and gravity studies of Mono Lake, east-central, California

    USGS Publications Warehouse

    Athens, Noah D.; Ponce, David A.; Jayko, Angela S.; Miller, Matt; McEvoy, Bobby; Marcaida, Mae; Mangan, Margaret T.; Wilkinson, Stuart K.; McClain, James S.; Chuchel, Bruce A.; Denton, Kevin M.

    2014-01-01

    From August 26 to September 5, 2011, the U.S. Geological Survey (USGS) collected more than 600 line-kilometers of shipborne magnetic data on Mono Lake, 20 line-kilometers of ground magnetic data on Paoha Island, 50 gravity stations on Paoha and Negit Islands, and 28 rock samples on Paoha and Negit Islands, in east-central California. Magnetic and gravity investigations were undertaken in Mono Lake to study regional crustal structures and to aid in understanding the geologic framework, in particular regarding potential geothermal resources and volcanic hazards throughout Mono Basin. Furthermore, shipborne magnetic data illuminate local structures in the upper crust beneath Mono Lake where geologic exposure is absent. Magnetic and gravity methods, which sense contrasting physical properties of the subsurface, are ideal for studying Mono Lake. Exposed rock units surrounding Mono Lake consist mainly of Quaternary alluvium, lacustrine sediment, aeolian deposits, basalt, and Paleozoic granitic and metasedimentary rocks (Bailey, 1989). At Black Point, on the northwest shore of Mono Lake, there is a mafic cinder cone that was produced by a subaqueous eruption around 13.3 ka. Within Mono Lake there are several small dacite cinder cones and flows, forming Negit Island and part of Paoha Island, which also host deposits of Quaternary lacustrine sediments. The typical density and magnetic properties of young volcanic rocks contrast with those of the lacustrine sediment, enabling us to map their subsurface extent.

  8. Deposition and remaining productive capabilities of the Upper Cretaceous Eutaw sands of East-Central Mississippi

    SciTech Connect

    Greer, B.R.

    1995-10-01

    Nearing the close of the Cretaceous, there were several transgressions and regressions of the epicontinental seas. These rapid changes in sea level played a large part in the depositing and reworking of the Eutaw sands of East-Central Mississippi. The study area includes Jasper, Jones, Clarke and Wayne Counties. The Eutaw sands of this area are described as fine to very fine grained sand which are glauconitic, micaceous and sometimes fossiliferous. This indicates that the environment of deposition was in the neritic zone of the continental shelf. Its high porosities and permeabilities along with its prolific nature makes this formation one of the most sought after reservoirs of the state of Mississippi. All of the 18 Eutaw fields in the study area are closely reaching their economic limits for primary production. Four of these fields have undergone successful waterfloods which have greatly enhanced their ultimate recoveries. The remaining fields in the study area have the potential of yielding millions of barrels of oil from secondary and tertiary recovery methods.

  9. Acheulean technological behaviour in the Middle Pleistocene landscape of Mieso (East-Central Ethiopia).

    PubMed

    de la Torre, Ignacio; Mora, Rafael; Arroyo, Adrian; Benito-Calvo, Alfonso

    2014-11-01

    The Mieso valley is a new paleoanthropological sequence located in East-Central Ethiopia. It contains Middle and Upper Pleistocene deposits with fossil and lithic assemblages in stratified deposits. This paper introduces the Middle Pleistocene archaeological sequence, attributed to the late Acheulean. Low density clusters of artefacts suggest short-term use of the landscape by Acheulean hominins. In Mieso 31, one of the excavated assemblages, refit sets indicate fragmentation of the reduction sequences and enable study of the initial stages of biface manufacture. Mieso 7, also a stratified site, is primarily characterized by a small concentration of standardized cleavers, and portrays another dimension of Acheulean technology, that related to final stages of use and discard of large cutting tools. Available radiometric dates place the Mieso Acheulean around 212 ka (thousands of years) ago, which would make this sequence among the latest evidence of the Acheulean in East Africa, in a time span when the Middle Stone Age is already documented in the region. PMID:25063567

  10. Vitrinite reflectance of sinkhole coals, east central Missouri fire clay district

    SciTech Connect

    Laudon, R.C. . Dept. of Geology and Geophysics)

    1993-03-01

    East central Missouri contains numerous sinkholes many of which are filled with commercial quantities of fire clay and some contain small amounts of coal. Vitrinite reflectance averages from 513 samples taken from eleven of these coals ranged from 0.71 to 0.78. Data were remarkably consistent and no local trends were observed. Using Barker and Goldstein (1990) and Barker and Pawlewicz (1986) temperature correlations, these measurements suggest that the coals have been heated to temperatures on the order of 108 C to 128 C (average = 116). These temperatures are considered anomalously high when compared against known geothermal gradients and burial depths for these rocks. The temperatures suggest that the sinkhole coals have been heated by some thermal event, possibly associated with Mississippi Valley type mineralization. These temperatures are consistent with regional trends in the state. This data, when combined with other vitrinite reflectance and fluid inclusion data (right), suggest that southwest Missouri (Tristate) and southeast Missouri (Viburnum Trend) were hot spots, and that temperatures decrease regionally away from these two areas.

  11. Aerobiological study in east-central Iberian Peninsula: pollen diversity and dynamics for major taxa.

    PubMed

    Pérez-Badia, Rosa; Rapp, Ana; Vaquero, Consolación; Fernández-González, Federico

    2011-01-01

    A study was made of airborne pollen counts in Cuenca (east-central Iberian Peninsula, Spain), using data obtained over a 3-year period (2008-2010). This is the first such study carried out in the World Heritage city of Cuenca, situated in the large region of Castilla-La Mancha. Air monitoring was performed using the sampling and analysis procedures recommended by the Spanish Aerobiology Network. Sampling commenced in mid- 2007, and provided the first recorded pollen-spectrum for the area. The greatest pollen-type diversity was recorded in spring, whilst the highest pollen counts (over 80 percent of the annual total) were observed between February and June. The lowest counts were found in September, November and December. The 10 leading taxa, in order of abundance, were: Cupressaceae, Quercus, Urticaceae, Pinus, Olea, Poaceae, Populus, Platanus, Chenopodiaceae-Amaranthaceae and Plantago. The pollen calendar was thus typically Mediterrean, and comprised the 27 pollen types reaching 10-day mean counts of over 1 grain/m(3) of air. Maximum concentration values during the day were recorded between 12:00-20:00, coinciding with the highest temperatures and lowest humidity levels. The pollen types responsible for most allergies in the city of Cuenca, ordered by the number of days on which risk levels were reached, were: Poaceae, Urticaceae, Cupressaceae, Olea, Platanus and Chenopodiaceae-Amaranthaceae. PMID:21736275

  12. Unusual carbonate-rich dikes and lamprophyres in Porcupine Dome, east-central Montana

    SciTech Connect

    Doden, A.G.; Gold, D.P. . Dept. of Geosciences)

    1992-01-01

    Isolated carbonate dikes and lamprophyric plugs are exposed in Porcupine dome, a Laramide structure in east-central Montana. En echelon sets of carbonate dikes strike N70E, consistent with regional lineaments and local normal faults. Individual dikes are steeply dipping, only 30--70 cm in width, and up to 1 km in length. These dikes exhibit unequivocal magmatic characteristics, including chilled margins, flow-aligned micas, multiple intrusive stages, country rock xenoliths, and local small blows'' containing well-rounded carbonate autoliths. Spatially associated with the dikes are small plugs of olivine-phlogopite-garnet-carbonate-bearing silicate rocks and a diatreme of bedded tuffs with xenoliths of country rocks. The dikes consistent primarily of calcite and dolomite, phlogopite, and opaque oxides. Although the dikes are relatively homogeneous mineralogically along strike, some chemical variations are apparent in the vicinity of the plugs/diatreme. Phlogopites and carbonates, common to both dikes and plugs, may provide a genetic link between these spatially associated intrusions. These unusual associations of dikes, plugs and diatremes are not restricted to Porcupine dome, but extend at least as far as the Grassrange - Winnett area, 100 km to the NW. The regional distribution of these small carbonatite bodies suggests a different magmatic process from typical carbonatites and alkaline complexes. The closest analogy is the carbonate dikes in the Premier Diamond Mine, South Africa.

  13. Sequence stratigraphy of the Lower Triassic Sinbad Formation, San Rafael Swell, east-central, Utah

    SciTech Connect

    Goodspeed, T.H.; Elrick, M. . Dept. of Earth and Planetary Sciences); Lucas, S.G. )

    1993-04-01

    The Lower Triassic Sinbad Fm (20--30 m thick) in the San Rafael Swell of east-central Utah is high energy carbonate deposits that conformably overlie tidal flat/fluvial channel deposits of the Black Dragon Fm. The Torrey Fm conformably overlies the Sinbad Fm and consists primarily of siliciclastic tidal flat and fluvial deposits. Five facies (in ascending order) are characteristic of the Sinbad Fm: (1) bioturbated calcisiltite with calcite-replaced evaporite nodules and ripple laminations, (2) skeletal-oolitic-intraclastic packstone and grainstone, (3) slightly bioturbated, mechanically laminated, pelletal calcisiltite (5) trough cross-bedded, peloidal to oolitic grainstone, and (5) thin-bedded, skeletal-pelletal-oolitic grainstone with mud to wackestone drapes. Regional facies relationships of the Sinbad Fm indicate initial deepening followed by shallowing. The skeletal-intraclastic packstone and grainstone facies represents maximum flooding. This facies thickens to the northwest and contains an open marine molluscan fauna of ammonites, bivalves, gastropods and scaphopods. The ammonites are indicative of the Tardus Zone of late Smithian age. Deposits above the maximum flooding zone (MFZ) are restricted foreshoal, pelletal calcisiltite, oolitic shoal, and backshoal skeletal-oolitic (with a restricted fauna of molluscs and ostracods) deposits. This shallowing-upward sequence represents the early HST. The Sinbad Fm represents the MFZ and early HST of a 150-m-thick depositional sequence of rocks with the Black Dragon FM representing the TST, and the Torrey Fm representing the late HST.

  14. Relationship between habitat type, fire frequency, and Amblyomma americanum populations in east-central Alabama.

    PubMed

    Willis, Damien; Carter, Robert; Murdock, Chris; Blair, Benjie

    2012-12-01

    Ticks were collected from 20 sites in the Calhoun, Cherokee, and Cleburne Counties in east-central Alabama areas to determine the relationship between plant physiognomy, environmental variables, and tick populations. Sites investigated included various burning regimes, wildland-urban-interface (WUI), a college campus, and an unmanaged area. Amblyomma americanum (L.) (Acari: Ixodidae) dominated the tick population while Ixodes scapularis Say was not encountered. There were complex differences in tick populations among site conditions. After prescribed burning, the tick population size was small but was larger in subsequent 2- and 5-year post-burn sites. An increase in Odocoileus virginianus foraging in recently burned sites is likely responsible for this phenomenon. WUI areas had the largest tick populations likely due to Odocoileus virginianus activity in an area that provides cover, forage, and a connection to a wildlife refuge. It is possible that the likelihood of humans coming in contact with ticks and tick-borne diseases is greater in WUI areas than in unbroken contiguous forest. A. americanum showed a positive correlation with percent cover of grass and leaf litter mass and a negative relationship with pine sapling density. Variables expected to be strongly correlated with A. americanum populations such as soil moisture, canopy closure, and tree density were found to have weak correlations. PMID:23181862

  15. Water Quality of a Reservoir and Its Major Tributary Located in East-Central Mexico

    PubMed Central

    Castilla-Hernández, Patricia; Torres-Alvarado, María del Rocío; Herrera-San Luis, José Antonio; Cruz-López, Norma

    2014-01-01

    A reservoir with ecological and economic importance and its major tributary, localized in east-central Mexico, were studied. The aim of this work was to know the physicochemical water characteristics of both water bodies and to contrast these by their different uses, and also estimate overall water quality using a Water Quality Index (WQI). Water samples from the reservoir and the tributary were obtained in different climatic seasons. In the tributary, anoxic and hypoxic conditions and high levels of organic matter, orthophosphate, and ammonium showed that this is strongly impacted by wastewater discharges and that the water is not suitable for different uses; independently of the season, the WQI showed “poor” quality (34.4–47.2). In contrast, in the reservoir a better water quality was determined; the WQI in the sampling months ranged from 72.1–76.6 (“good” quality), and spatially, this was from 66.5–79.5 (“fair” and “good” quality). PMID:24919132

  16. Establishing an Online Continuing and Professional Development Library for Nurses and Midwives in East, Central, and Southern Africa.

    PubMed

    Hosey, Kristen N; Kalula, Alphonce; Voss, Joachim

    2016-01-01

    Over the past 4 years, the African Health Profession Regulatory Collaborative for nurses and midwives has supported 12 countries establish national continuing and professional development frameworks and programs, linking continuing education to nursing and midwifery re-licensure through technical assistance and improvement grants. However, lack of electronic media and rural practice sites, differences in priority content, and varying legal frameworks make providing accessible, certifiable, and up-to-date online continuing education content for the more than 300,000 nurses and midwives in the 17 member countries of the East, Central, and Southern Africa College of Nursing a major challenge. We report here on how the East, Central, and Southern Africa College of Nursing, with technical assistance from an Afya Bora Fellow, developed an online continuing professional development library hosted on their Web site using data collected in a survey of nursing and midwifery leaders in the region. PMID:27086190

  17. The Oldest Case of Decapitation in the New World (Lapa do Santo, East-Central Brazil)

    PubMed Central

    Strauss, André; Oliveira, Rodrigo Elias; Bernardo, Danilo V.; Salazar-García, Domingo C.; Talamo, Sahra; Jaouen, Klervia; Hubbe, Mark; Black, Sue; Wilkinson, Caroline; Richards, Michael Phillip; Araujo, Astolfo G. M.; Kipnis, Renato; Neves, Walter Alves

    2015-01-01

    We present here evidence for an early Holocene case of decapitation in the New World (Burial 26), found in the rock shelter of Lapa do Santo in 2007. Lapa do Santo is an archaeological site located in the Lagoa Santa karst in east-central Brazil with evidence of human occupation dating as far back as 11.7–12.7 cal kyBP (95.4% interval). An ultra-filtered AMS age determination on a fragment of the sphenoid provided an age range of 9.1–9.4 cal kyBP (95.4% interval) for Burial 26. The interment was composed of an articulated cranium, mandible and first six cervical vertebrae. Cut marks with a v-shaped profile were observed in the mandible and sixth cervical vertebra. The right hand was amputated and laid over the left side of the face with distal phalanges pointing to the chin and the left hand was amputated and laid over the right side of the face with distal phalanges pointing to the forehead. Strontium analysis comparing Burial 26’s isotopic signature to other specimens from Lapa do Santo suggests this was a local member of the group. Therefore, we suggest a ritualized decapitation instead of trophy-taking, testifying for the sophistication of mortuary rituals among hunter-gatherers in the Americas during the early Archaic period. In the apparent absence of wealth goods or elaborated architecture, Lapa do Santo’s inhabitants seemed to use the human body to express their cosmological principles regarding death. PMID:26397983

  18. Uncertainty analysis of a groundwater flow model in East-central Florida.

    PubMed

    Sepúlveda, Nicasio; Doherty, John

    2015-01-01

    A groundwater flow model for east-central Florida has been developed to help water-resource managers assess the impact of increased groundwater withdrawals from the Floridan aquifer system on heads and spring flows originating from the Upper Floridan Aquifer. The model provides a probabilistic description of predictions of interest to water-resource managers, given the uncertainty associated with system heterogeneity, the large number of input parameters, and a nonunique groundwater flow solution. The uncertainty associated with these predictions can then be considered in decisions with which the model has been designed to assist. The "Null Space Monte Carlo" method is a stochastic probabilistic approach used to generate a suite of several hundred parameter field realizations, each maintaining the model in a calibrated state, and each considered to be hydrogeologically plausible. The results presented herein indicate that the model's capacity to predict changes in heads or spring flows that originate from increased groundwater withdrawals is considerably greater than its capacity to predict the absolute magnitudes of heads or spring flows. Furthermore, the capacity of the model to make predictions that are similar in location and in type to those in the calibration dataset exceeds its capacity to make predictions of different types at different locations. The quantification of these outcomes allows defensible use of the modeling process in support of future water-resources decisions. The model allows the decision-making process to recognize the uncertainties, and the spatial or temporal variability of uncertainties that are associated with predictions of future system behavior in a complex hydrogeological context. PMID:25040026

  19. Seasonal phenology of the cerambycid beetles of east-central Illinois

    PubMed Central

    Hanks, Lawrence M.; Reagel, Peter F.; Mitchell, Robert F.; Wong, Joseph C. H.; Meier, Linnea R.; Silliman, Christina A.; Graham, Elizabeth E.; Striman, Becca L.; Robinson, Kenneth P.; Mongold-Diers, Judith A.; Millar, Jocelyn G.

    2014-01-01

    We summarize field data on the species composition and seasonal phenology of the community of cerambycid beetles of east-central Illinois. Data were drawn from field bioassays conducted during 2009 – 2012 that tested attraction of adult beetles of diverse species to a variety of synthetic pheromones and host plant volatiles. A total of 34,086 beetles of 114 species were captured, including 48 species in the subfamily Cerambycinae, 41 species in the Lamiinae, 19 species in the Lepturinae, two species in the Spondylidinae, and one species each in the Necydalinae, Parandrinae, Prioninae, and the Disteniidae. Most of the best-represented species were attracted to pheromones that were included in field experiments, particularly species that use (R)-3-hydroxyhexan-2-one as a pheromone component. The species captured, and their patterns of abundance and seasonal phenology were similar to those in an earlier study conducted in Pennsylvania. The most abundant species identified in both studies included the cerambycines Elaphidion mucronatum (Say), Neoclytus a. acuminatus (F.), Neoclytus m. mucronatus (F.), and Xylotrechus colonus (F.). Cerambycine species became active in an orderly progression from early spring through late fall, whereas most lamiine species were active in summer and fall, and lepturine species were limited to summer. Potential cross attraction between some cerambycine species that shared pheromone components may have been averted by differences in seasonal activity period, and by minor pheromone components that acted as synergists for conspecifics and/or antagonists for heterospecifics. These results provide quantitative data on the abundance and seasonal phenology of a large number of species. PMID:24683267

  20. The Oldest Case of Decapitation in the New World (Lapa do Santo, East-Central Brazil).

    PubMed

    Strauss, André; Oliveira, Rodrigo Elias; Bernardo, Danilo V; Salazar-García, Domingo C; Talamo, Sahra; Jaouen, Klervia; Hubbe, Mark; Black, Sue; Wilkinson, Caroline; Richards, Michael Phillip; Araujo, Astolfo G M; Kipnis, Renato; Neves, Walter Alves

    2015-01-01

    We present here evidence for an early Holocene case of decapitation in the New World (Burial 26), found in the rock shelter of Lapa do Santo in 2007. Lapa do Santo is an archaeological site located in the Lagoa Santa karst in east-central Brazil with evidence of human occupation dating as far back as 11.7-12.7 cal kyBP (95.4% interval). An ultra-filtered AMS age determination on a fragment of the sphenoid provided an age range of 9.1-9.4 cal kyBP (95.4% interval) for Burial 26. The interment was composed of an articulated cranium, mandible and first six cervical vertebrae. Cut marks with a v-shaped profile were observed in the mandible and sixth cervical vertebra. The right hand was amputated and laid over the left side of the face with distal phalanges pointing to the chin and the left hand was amputated and laid over the right side of the face with distal phalanges pointing to the forehead. Strontium analysis comparing Burial 26's isotopic signature to other specimens from Lapa do Santo suggests this was a local member of the group. Therefore, we suggest a ritualized decapitation instead of trophy-taking, testifying for the sophistication of mortuary rituals among hunter-gatherers in the Americas during the early Archaic period. In the apparent absence of wealth goods or elaborated architecture, Lapa do Santo's inhabitants seemed to use the human body to express their cosmological principles regarding death. PMID:26397983

  1. Exploration potential and variations in shelf plume sandstones, Navarro group (Maestrichtian), east-central Texas

    SciTech Connect

    Patterson, J.E. Jr.; Scott, A.J.

    1984-04-01

    Fine-grained marine sandstones within the Kemp Clay of the Navarro Group (Maestrichtian) of east-central Texas were deposited on a muddy, shallow shelf by migrating sandbars. These sands were transported in traction from deltaic headlands by seaward-deflected coastal/shelf currents. The sand formed thin (3-20 ft; 1-6 m) arcuate belts (shelf sand plumes) which were 17-20 mi (27-32 km) wide and extended 27-30 mi (43-48 km) downdrift and 21-40 mi (34-64 km) onto the shelf. Orientation of the long axes of ridges, formed by the stacking of individual bars within the shelf sand plume, changes (from dip to strike-oriented downdrift) corresponding to the flow directions of the shelf currents. Southwestward, fair-weather reworking of these delta-supplied sands by shelf currents resulted in the down-current stratigraphic climbing of the migrating shelf-bar complexes. Onshore stratigraphic climbing in the landward parts of the plume complexes was related to storm activity. Current patterns and the resulting distribution of sand were influenced by the configuration of the shelf and the topographic relief inherited from previously deposited deltaic/shelf depositional platforms. Three variations of the basic shelf sandstone-plume model were recognized in the study area: (1) a rapidly deposited, immature plume, (2) an abandoned, current-reworked plume, and (3) a storm-modified, onshore-reworked plume. Each of these variants displays unique characteristics which influence their potential as hydrocarbon reservoirs.

  2. Variation of Soil Organic Carbon and Its Major Constraints in East Central Asia.

    PubMed

    Lee, Xinqing; Huang, Yimin; Huang, Daikuan; Hu, Lu; Feng, Zhaodong; Cheng, Jianzhong; Wang, Bing; Ni, Jian; Shurkhuu, Tserenpil

    2016-01-01

    Variation of soil organic carbon (SOC) and its major constraints in large spatial scale are critical for estimating global SOC inventory and projecting its future at environmental changes. By analyzing SOC and its environment at 210 sites in uncultivated land along a 3020km latitudinal transect in East Central Asia, we examined the effect of environmental factors on the dynamics of SOC. We found that SOC changes dramatically with the difference as high as 5 times in north China and 17 times in Mongolia. Regardless, C:N remains consistent about 12. Path analysis indicated that temperature is the dominant factor in the variation of SOC with a direct effect much higher than the indirect one, the former breaks SOC down the year round while the latter results in its growth mainly via precipitation in the winter half year. Precipitation helps accumulate SOC, a large part of the effect, however, is taken via temperature. NH4+-N and topography also affect SOC, their roles are played primarily via climatic factors. pH correlates significantly with SOC, the effect, however, is taken only in the winter months, contributing to the decay of SOC primarily via temperature. These factors explained as much as 79% of SOC variations, especially in the summer months, representing the major constraints on the SOC stock. Soil texture gets increasingly fine southward, it does not, however, constitute an apparent factor. Our results suggested that recent global warming should have been adversely affecting SOC stock in the mid-latitude as temperature dominates other factors as the constraint. PMID:26934707

  3. Ground-water quality in east-central New Jersey, and a plan for sampling networks

    USGS Publications Warehouse

    Harriman, D.A.; Sargent, B.P.

    1985-01-01

    Groundwater quality was evaluated in seven confined aquifers and the water table aquifer in east-central New Jersey based on 237 analyses of samples collected in 1981-82, and 225 older analyses. Investigation of the effect of land use on water quality and several sampling network proposals for the region are reported. Generally, water in the confined aquifers is of satisfactory quality for human consumption and most other uses. Iron (Fe) and manganese (Mn) concentrations exceed U.S. EPA drinking water standards in some wells screened in the Potomac-Raritan-Magothy aquifer system. Sodium (Na) concentrations in samples from three wells more than 800 ft deep in the Englishtown aquifer exceed the standard. Iron and Mn concentrations in this aquifer may also exceed the standards. Iron concentrations in the Wenonah-Mount Laurel aquifer exceed the standard. Based on 15 analyses of water from the Vincetown aquifer, Mn is the only constituent that exceeds the drinking water standard. In the Manasquan aquifer, 4 of the 16 Na determinations exceed the standard, and 8 of 16 Fe determinations exceed the standard. Water quality in the Atlantic City 800-ft sand is generally satisfactory. However, 12 Fe and 1 of 12 Mn determinations exceed the standards. For the Rio Grande water-bearing zone, 1 of 3 Fe determinations exceed the standard. The Kirkwood-Cohansey aquifer system (the water table aquifer) was the most thoroughly sampled (249 chemical analyses from 209 wells). Dissolved solids, chloride, Fe, nitrate, and Mn concentrations exceed drinking water standards in some areas. The results of chi-square tests of constituent distributions based on analyses from 158 wells in the water table aquifer indicate that calcium is higher in industrial and commercial areas; and Mg, chloride, and nitrate-plus-nitrite is higher in residential areas. (Author 's abstract)

  4. Uncertainty analysis of a groundwater flow model in east-central Florida

    USGS Publications Warehouse

    Sepulveda, Nicasio; Doherty, John E.

    2014-01-01

    A groundwater flow model for east-central Florida has been developed to help water-resource managers assess the impact of increased groundwater withdrawals from the Floridan aquifer system on heads and spring flows originating from the Upper Floridan aquifer. The model provides a probabilistic description of predictions of interest to water-resource managers, given the uncertainty associated with system heterogeneity, the large number of input parameters, and a nonunique groundwater flow solution. The uncertainty associated with these predictions can then be considered in decisions with which the model has been designed to assist. The “Null Space Monte Carlo” method is a stochastic probabilistic approach used to generate a suite of several hundred parameter field realizations, each maintaining the model in a calibrated state, and each considered to be hydrogeologically plausible. The results presented herein indicate that the model’s capacity to predict changes in heads or spring flows that originate from increased groundwater withdrawals is considerably greater than its capacity to predict the absolute magnitudes of heads or spring flows. Furthermore, the capacity of the model to make predictions that are similar in location and in type to those in the calibration dataset exceeds its capacity to make predictions of different types at different locations. The quantification of these outcomes allows defensible use of the modeling process in support of future water-resources decisions. The model allows the decision-making process to recognize the uncertainties, and the spatial/temporal variability of uncertainties that are associated with predictions of future system behavior in a complex hydrogeological context.

  5. Dynamics of stormflow generation - A hillslope-scale field study in east-central Pennsylvania, USA

    NASA Astrophysics Data System (ADS)

    Srinivasan, M. S.; Gburek, W. J.; Hamlett, J. M.

    2002-02-01

    A 40 m × 20 m mowed, grass hillslope adjacent to a headwater stream within a 26-ha watershed in east-central Pennsylvania, USA, was instrumented to identify and map the extent and dynamics of surface saturation (areas with the water table at the surface) and surface runoff source areas. Rainfall, stream flow and surface runoff from the hillslope were recorded at 5-min intervals from 11 August to 22 November 1998, and 13 April to 12 November 1999. The dynamics of the water table (0 to 45 cm depth from the soil surface) and the occurrence of surface runoff source areas across the hillslope were recorded using specially designed subsurface saturation and surface runoff sensors, respectively. Detailed data analyses for two rainfall events that occurred in August (57·7 mm in 150 min) and September (83·6 mm in 1265 min) 1999, illustrated the spatial and temporal dynamics of surface saturation and surface runoff source areas. Temporal data analyses showed the necessity to measure the hillslope dynamics at time intervals comparable to that of rainfall measurements. Both infiltration excess surface runoff (runoff caused when rainfall intensity exceeds soil infiltration capacity) and saturation excess surface runoff (runoff caused when soil moisture storage capacity is exceeded) source areas were recorded during these rainfall events. The August rainfall event was primarily an infiltration excess surface runoff event, whereas the September rainfall event produced both infiltration excess and saturation excess surface runoff. Occurrence and disappearance of infiltration excess surface runoff source areas during the rainfall events appeared scattered across the hillslope. Analysis of surface saturation and surface runoff data showed that not all surface saturation areas produced surface runoff that reached the stream. Emergence of subsurface flow to the surface during the post-rainfall periods appeared to be a major flow process dominating the hillslope after the August

  6. Drunkard's wash project: Coalbed methane production from Ferron coals in east-central Utah

    SciTech Connect

    Lemarre, R.A. ); Burns, T.D. )

    1996-01-01

    The Drunkard's Wash Project produces dry, coalbed methane gas from coals within the Ferron Sandstone Member of the Mancos Shale. The project covers 120,000 acres on the western flank of the San Rafael Uplift in east-central Utah. Gas was first produced into the sales line in January 1993. The field is being developed on 160 acre spacing with 73 wells currently producing 32.2 MMCFD for an average of 437 MCFD/well. Thirty three of those wells have been producing for 32 months and now average 637 MCFD/well. Most of the wells show a classic coalbed methane negative decline curve with increasing gas rates as the reservoir pressure declines due to production of water. Daily water production is 14,500 BPD, for an average of 199 BWPD/well. Total coal thickness ranges from 7 ft. to 48 ft., with an average of 24 ft. The coals occur in 3 to 6 seams at depths of 1350 to 2450 ft. The coal rank is high volatile A B bituminous. We can not yet see a correlation between total coal thickness and current production. All wells are cased and hydraulically stimulated and most require pumping units to handle the large volumes of water. However, 22 wells do not require pumps and flow unassisted to the surface. The structure consists of monoclinal westward dip. A thin tonstein layer in the bottom coal seam serves as an excellent datum for mapping. Enhanced production is encountered along a southwest-plunging nose that probably formed additional fracture permeability within the coals. Northeast-trending reverse faults with small displacement appear to compartmentalize the reservoir. The Ferron coals were deposited in a river-dominated deltaic system that prograded to the east and southeast during Turonian-Coniacian (Upper Cretaceous) time. The Ferron Sandstone Member represents an eastward-thinning elastic wedge that was deposited during regression of the Western Interior Cretaceous seaway.

  7. Drunkard`s wash project: Coalbed methane production from Ferron coals in east-central Utah

    SciTech Connect

    Lemarre, R.A.; Burns, T.D.

    1996-12-31

    The Drunkard`s Wash Project produces dry, coalbed methane gas from coals within the Ferron Sandstone Member of the Mancos Shale. The project covers 120,000 acres on the western flank of the San Rafael Uplift in east-central Utah. Gas was first produced into the sales line in January 1993. The field is being developed on 160 acre spacing with 73 wells currently producing 32.2 MMCFD for an average of 437 MCFD/well. Thirty three of those wells have been producing for 32 months and now average 637 MCFD/well. Most of the wells show a classic coalbed methane negative decline curve with increasing gas rates as the reservoir pressure declines due to production of water. Daily water production is 14,500 BPD, for an average of 199 BWPD/well. Total coal thickness ranges from 7 ft. to 48 ft., with an average of 24 ft. The coals occur in 3 to 6 seams at depths of 1350 to 2450 ft. The coal rank is high volatile A&B bituminous. We can not yet see a correlation between total coal thickness and current production. All wells are cased and hydraulically stimulated and most require pumping units to handle the large volumes of water. However, 22 wells do not require pumps and flow unassisted to the surface. The structure consists of monoclinal westward dip. A thin tonstein layer in the bottom coal seam serves as an excellent datum for mapping. Enhanced production is encountered along a southwest-plunging nose that probably formed additional fracture permeability within the coals. Northeast-trending reverse faults with small displacement appear to compartmentalize the reservoir. The Ferron coals were deposited in a river-dominated deltaic system that prograded to the east and southeast during Turonian-Coniacian (Upper Cretaceous) time. The Ferron Sandstone Member represents an eastward-thinning elastic wedge that was deposited during regression of the Western Interior Cretaceous seaway.

  8. Modeling riverine nitrate export from an East-Central Illinois watershed using SWAT.

    PubMed

    Hu, X; McIsaac, G F; David, M B; Louwers, C A L

    2007-01-01

    Reliable water quality models are needed to forecast the water quality consequences of different agricultural nutrient management scenarios. In this study, the Soil and Water Assessment Tool (SWAT), version 2000, was applied to simulate streamflow, riverine nitrate (NO(3)) export, crop yield, and watershed nitrogen (N) budgets in the upper Embarras River (UER) watershed in east-central Illinois, which has extensive maize-soybean cultivation, large N fertilizer input, and extensive tile drainage. During the calibration (1994-2002) and validation (1985-1993) periods, SWAT simulated monthly and annual stream flows with Nash-Sutcliffe coefficients (E) ranging from 0.67 to 0.94 and R(2) from 0.75 to 0.95. For monthly and annual NO(3) loads, E ranged from -0.16 to 0.45 and R(2) from 0.36 to 0.74. Annual maize and soybean yields were simulated with relative errors ranging from -10 to 6%. The model was then used to predict the changes in NO(3) output with N fertilizer application rates 10 to 50% lower than original application rates in UER. The calibrated SWAT predicted a 10 to 43% decrease in NO(3) export from UER and a 6 to 38% reduction in maize yield in response to the reduction in N fertilizer. The SWAT model markedly overestimated NO(3) export during major wet periods. Moreover, SWAT estimated soybean N fixation rates considerably greater than literature values, and some simulated changes in the N cycle in response to fertilizer reduction seemed to be unrealistic. Improving these aspects of SWAT could lead to more reliable predictions in the water quality outcomes of nutrient management practices in tile-drained watersheds. PMID:17526878

  9. Variation of Soil Organic Carbon and Its Major Constraints in East Central Asia

    PubMed Central

    Lee, Xinqing; Huang, Yimin; Huang, Daikuan; Hu, Lu; Feng, Zhaodong; Cheng, Jianzhong; Wang, Bing; Ni, Jian; Shurkhuu, Tserenpil

    2016-01-01

    Variation of soil organic carbon (SOC) and its major constraints in large spatial scale are critical for estimating global SOC inventory and projecting its future at environmental changes. By analyzing SOC and its environment at 210 sites in uncultivated land along a 3020km latitudinal transect in East Central Asia, we examined the effect of environmental factors on the dynamics of SOC. We found that SOC changes dramatically with the difference as high as 5 times in north China and 17 times in Mongolia. Regardless, C:N remains consistent about 12. Path analysis indicated that temperature is the dominant factor in the variation of SOC with a direct effect much higher than the indirect one, the former breaks SOC down the year round while the latter results in its growth mainly via precipitation in the winter half year. Precipitation helps accumulate SOC, a large part of the effect, however, is taken via temperature. NH4+-N and topography also affect SOC, their roles are played primarily via climatic factors. pH correlates significantly with SOC, the effect, however, is taken only in the winter months, contributing to the decay of SOC primarily via temperature. These factors explained as much as 79% of SOC variations, especially in the summer months, representing the major constraints on the SOC stock. Soil texture gets increasingly fine southward, it does not, however, constitute an apparent factor. Our results suggested that recent global warming should have been adversely affecting SOC stock in the mid-latitude as temperature dominates other factors as the constraint. PMID:26934707

  10. Preliminary evaluation of the 15 October 1972 ERTS-1 imagery of east central Ohio (scene 1034-15415)

    NASA Technical Reports Server (NTRS)

    Pettyjohn, W. A. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Results of a general, physical interpretation of ERTS-1 imagery of east central Ohio are presented. Special emphasis is placed upon geologic features, such as linear features and hydrologic features. Man-made features are included as a matter of interest and image location. The interpretation is compared to available maps of the area and from this an assessment that ERTS-1 is potentially useful for updating and producing geological maps.

  11. Measuring and modeling ancient meteoric water in volcanic glass, with application to the paleotopography of the US Cordilleran hinterland

    NASA Astrophysics Data System (ADS)

    Cassel, E. J.; Breecker, D.; Larson, T.; Henry, C.

    2013-12-01

    relative elevations. We used δD values of hydration waters in natural glasses to reconstruct absolute elevations across the Cordilleran hinterland for the Paleogene, using a thermodynamic air mass lifting Rayleigh condensation model incorporating isotope equilibrium expressions, validated by comparison with observed modern isotopic lapse rates. The potential for topography to block and deflect atmospheric flow, departures from modern temperature lapse rates, and initial air mass temperature and humidity were also considered. The Paleogene Cordilleran hinterland maintained a connected drainage system for over 300 km to the west of a region of periodically closed intraorogenic basins. Late Oligocene paleoelevations reached 3500 +800/-300 m in what is now eastern Nevada (average modern elevation: 1500 m), with a continuous westward-facing paleoslope of 0.8%-1.5% grade. This high topography was sustained from at least 40-23 Ma. The onset of extension and collapse, facilitated by internal heat production and stored gravitational potential energy within elevated, thickened crust, was triggered by a change in the external kinematic framework - likely the delamination of the Farallon slab, which coupled the Sierra Nevada to the Colorado Plateau.

  12. Evolution of the east-central San Jose del Cabo basin, Baja California Sur, Mexico

    NASA Astrophysics Data System (ADS)

    McTeague, M. S.; Umhoefer, P. J.; Schwennicke, T.; Ingle, J. C.; Cortes Martinez, M.

    2006-12-01

    The San Jose del Cabo basin at the southern tip of the Baja California peninsula records the early tectonic evolution of the west side of the Gulf of California. This study focused on the east central margin of the basin. The basal La Calera Formation unconformably overlies Cretaceous granite and consists of conglomerate, pebbly sandstone and conglomerate, and sandstone deposited in alluvial fans and fan-deltas. Deposition of the La Calera Formation was from ca. 9-14 Ma. The lower member of the Trinidad Formation was deposited beginning ca. 9-13 Ma and consists of sandstone, mudstone, and shelly mudstone deposited in nearshore and estuarine environments. These age estimates are based on sedimentation rates and foraminifera and coccoliths from the NN 11A nannozone (7.4 8.6 Ma, GTS 2004). The middle member of the Trinidad Formation consists of deeper water mudstones deposited by turbidity currents and suspension settling in a shelf to slope and conglomerates deposited by submarine debris flows on the shelf. The basin began earlier than previously thought. The oldest marine rocks are ca.9-13 Ma, while sedimentation on the east side began at ca. 9-14 Ma, synchronous with estimates of initiation of offset on the San Jose del Cabo fault. The Zapote fault is a down-to-the-east normal and sinistral-oblique fault that exposes a wedge of granite and older strata in the footwall to the west. The fault was active during sedimentation in the late Miocene and possibly later. The fault divides the study area into an eastern hanging wall subbasin and western footwall subbasin. The eastern subbasin formed an embayment in the eastern margin of the Cabo basin. A regional flooding surface (ca. 8 Ma) can be correlated across the fault that marks a major marine incursion. Depositional systems evolved rapidly from coarse-grained terrestrial systems to fine-grained marine and estuarine systems. The Cabo basin provides an excellent analogue for comparison with offshore basins, which are

  13. Preliminary Results of a Multi-Proxy Lake Sediment Core Study in East-Central France

    NASA Astrophysics Data System (ADS)

    Misner, T.; Meyers, S.; Rosenmeier, M.; Strano, S.; Straffin, E.

    2008-12-01

    This paper presents the preliminary results of a multi-proxy study of natural and human-induced changes in the Burgundian environment, as recorded in the sediment geochemistry of three small freshwater basins within the Arroux River Valley, east-central France. Accelerator mass spectrometry radiocarbon dates constrain the age of core material collected from the basins, and indicate that these mill and farm ponds were constructed by at least 1200 A.D. The pond sediments are predominantly massive, organic-rich muds that contain discrete sand and gravel lenses likely related to episodic flooding and/or basin drainage. In this study, continuous X-ray fluorescence (XRF) scanning is used to quantify bulk geochemical variability throughout the lake sediment cores, and to investigate specific elemental proxies for paleoenvironmental change (detrital flux, biogenic flux, and redox state). The high-resolution XRF data are supplemented by sediment magnetic susceptibility measurements, and organic matter concentration as determined by loss on ignition. These records demonstrate a general increase in detrital sediment input from 1200 to 1300 A.D., during a period of known regional agricultural expansion. We infer these changes to be the consequence of increased catchment soil erosion and material flux to the water bodies. The data also suggest changes in mill and farm pond primary productivity, also related to soil erosion and changing transport of soil nutrients to the basins. Near the onset of the Little Ice Age (ca. 1500 A.D.) pond productivity reductions are apparent, likely indicating colder climates. These mill and farm pond sedimentary archives, in conjunction with historic records, can be used to better understand past land management strategies. Furthermore, historically documented landscape changes can be examined within the context of prevailing climatic conditions over the last ~800 years in an effort to establish future best management practices and the most

  14. Geologic map of the Big Delta B-2 quadrangle, east-central Alaska

    USGS Publications Warehouse

    Day, Warren C.; Aleinikoff, John N.; Roberts, Paul; Smith, Moira; Gamble, Bruce M.; Henning, Mitchell W.; Gough, Larry P.; Morath, Laurie C.

    2003-01-01

    New 1:63,360-scale geologic mapping of the Big Delta B-2 quadrangle provides important data on the structural setting and age of geologic units, as well as on the timing of gold mineralization plutonism within the Yukon-Tanana Upland of east-central Alaska. Gold exploration has remained active throughout the region in response to the discovery of the Pogo gold deposit, which lies within the northwestern part of the quadrangle near the south bank of the Goodpaster River. Geologic mapping and associated geochronological and geochemical studies by the U.S. Geological Survey (USGS) and the Alaska Department of Natural Resources, Division of Mining and Water Management, provide baseline data to help understand the regional geologic framework. Teck Cominco Limited geologists have provided the geologic mapping for the area that overlies the Pogo gold deposit as well as logistical support, which has lead to a much improved and informative product. The Yukon-Tanana Upland lies within the Tintina province in Alaska and consists of Paleozoic and possibly older(?) supracrustal rocks intruded by Paleozoic (Devonian to Mississippian) and Cretaceous plutons. The oldest rocks in the Big Delta B-2 quadrangle are Paleozoic gneisses of both plutonic and sedimentary origin. Paleozoic deformation, potentially associated with plutonism, was obscured by intense Mesozoic deformation and metamorphism. At least some of the rocks in the quadrangle underwent tectonism during the Middle Jurassic (about 188 Ma), and were subsequently deformed in an Early Cretaceous contractional event between about 130 and 116 Ma. New U-Pb SHRIMP data presented here on zircons from the Paleozoic biotite gneisses record inherited cores that range from 363 Ma to about 2,130 Ma and have rims of euhedral Early Cretaceous metamorphic overgrowths (116 +/- 4 Ma), interpreted to record recrystallization during Cretaceous west-northwest-directed thrusting and folding. U-Pb SHRIMP dating of monazite from a Paleozoic

  15. Sedimentologic and stratigraphic constraints on emplacement of the Star Kimberlite, east-central Saskatchewan

    NASA Astrophysics Data System (ADS)

    Zonneveld, John-Paul; Kjarsgaard, Bruce A.; Harvey, Shawn E.; Heaman, Larry M.; McNeil, David H.; Marcia, Kirsten Y.

    2004-09-01

    Diamond-bearing kimberlites in the Fort à la Corne region, east-central Saskatchewan, consist primarily of extra-crater pyroclastic deposits which are interstratified with Lower Cretaceous (Albian and Cenomanian) marine, marginal marine and continental sediments. Approximately 70 individual kimberlite occurrences have been documented. The Star Kimberlite, occurring at the southeastern end of the main Fort à la Corne trend, has been identified as being of economic interest, and is characterized by an excellent drill core database. Integration of multi-disciplinary data-sets has helped to refine and resolve models for emplacement of the Star Kimberlite. Detailed core logging has provided the foundation for sedimentological and volcanological studies and for construction of a regionally consistent stratigraphic and architectural framework for the kimberlite complex. Micropaleontologic and biostratigraphic analysis of selected sedimentary rocks, and U-Pb perovskite geochronology on kimberlite samples have been integrated to define periods of kimberlite emplacement. Radiometric age determination and micropaleontologic evidence support the hypothesis that multiple kimberlite eruptive phases occurred at Star. The oldest kimberlite in the Star body erupted during deposition of the predominantly continental strata of the lower Mannville Group (Cantuar Formation). Kimberlites within the Cantuar Formation include terrestrial airfall deposits as well as fluvially transported kimberlitic sandstone and conglomerate. Successive eruptive events occurred contemporaneous with deposition of the marginal marine upper Mannville Group (Pense Formation). Kimberlites within the Pense Formation consist primarily of terrestrial airfall deposits. Fine- to medium-grained cross-stratified kimberlitic (olivine-dominated) sandstone in this interval reflects reworking of airfall deposits during a regional marine transgression. The location of the source feeder vents of the Cantuar and Pense

  16. Optimization for Hub-and-Spoke Port Logistics Network of Dynamic Hinterland

    NASA Astrophysics Data System (ADS)

    Ming-Jun, Ji; Yan-Ling, Chu

    The port logistics and its regional economic react on each other and develop in unison. This paper studies the Hub-and-Spoke port logistics network which is a transportation system between the sea routes and ports hinterland transport routes. An optimization model is proposed with the objective of the total transportation cost in the regional port group based on the conditions of dynamic hinterland. This paper not only ensures every port in the hub-and spoke port logistics network to achieve its maximum economic benefits, but also makes the entire system get the minimum total transportation cost in the view of quantitative point. In order to illustrate the validity of the model, the example was solved. The results show that the model is feasible. Furthermore, the competitiveness power of the port, the demarcation of hinterland and the traffic capacity are changed dynamically in the model, which is closer to the real system.

  17. Solar forcing of Holocene droughts in a stalagmite record from West Virginia in east-central North America

    NASA Astrophysics Data System (ADS)

    Springer, Gregory S.; Rowe, Harold D.; Hardt, Ben; Edwards, R. Lawrence; Cheng, Hai

    2008-09-01

    Elevated Sr/Ca ratios and δ 13C values in Holocene-age stalagmite BCC-002 from east-central North America record six centennial-scale droughts during the last five North Atlantic Ocean ice-rafted debris (IRD) episodes, previously ascribed to solar irradiance minima. Spectral and cross-spectral analyses of the multi-decadal resolution Sr/Ca and δ 13C time series yield coherent ~200 and ~500 years periodicities. The former is consistent with the de Vries solar irradiance cycle. Cross-spectral analysis of the Sr/Ca and IRD time series yields coherent periodicities of 715- and 455-years, which are harmonics of the 1,450 +/- 500 year IRD periodicity. These coherencies corroborate strong visual correlations and provide convincing evidence for solar forcing of east-central North American droughts and strengthen the case for solar modulation of mid-continent climates. Moisture transport across North America may have lessened during droughts because of weakened north-south temperature and pressure gradients caused by cooling of the tropical Pacific and Atlantic Oceans.

  18. Solar Forcing of Holocene Droughts in a Stalagmite Record From West Virginia in East- Central North America

    NASA Astrophysics Data System (ADS)

    Springer, G. S.; Rowe, H. D.; Hardt, B.; Edwards, R. L.; Cheng, H.

    2008-12-01

    Elevated Sr/Ca ratios and δ13C values in Holocene-age stalagmite BCC-002 from east-central North America record six centennial-scale droughts during the last five North Atlantic Ocean ice-rafted debris (IRD) episodes, previously ascribed to solar irradiance minima. Spectral and cross-spectral analyses of the multi-decadal resolution Sr/Ca and δ13C time series yield coherent ~200 and ~500 years periodicities. The former is consistent with the de Vries solar irradiance cycle. Cross-spectral analysis of the Sr/Ca and IRD time series yields coherent periodicities of 715- and 455-years, which are harmonics of the 1,450±500 year IRD periodicity. These coherencies corroborate strong visual correlations and provide convincing evidence for solar forcing of east-central North American droughts and strengthen the case for solar modulation of mid-continent climates. Moisture transport across North America may have lessened during droughts because of weakened north-south temperature and pressure gradients caused by cooling of the tropical Pacific and Atlantic Oceans.

  19. Stratiform zinc-lead mineralization in Nasina assemblage rocks of the Yukon-Tanana Upland in east-central Alaska

    USGS Publications Warehouse

    Dusel-Bacon, Cynthia; Bressler, Jason R.; Takaoka, Hidetoshi; Mortensen, James K.; Oliver, Douglas H.; Leventhal, Joel S.; Newberry, Rainer J.; Bundtzen, Thomas K.

    1998-01-01

    The Yukon-Tanana Upland of east-central Alaska and Yukon comprises thrust sheets of ductilely deformed metasedimentary and metaigneous rocks of uncertain age and origin that are overlain by klippen of weakly metamorphosed oceanic rocks of the Seventymile-Slide Mountain terrane, and intruded by post-kinematic Early Jurassic, Cretaceous and Tertiary granitoids. Metamorphosed continental margin strata in the Yukon-Tanana Upland of east-central Alaska are thought to be correlative, on the basis of stratigraphic similarities and sparse Mississippian U-Pb zircon and fossil ages (Mortensen, 1992), with middle Paleozoic metasedimentary and metavolcanic rocks in the eastern Alaska Range and in western and southeastern Yukon. Furthermore, rocks in the northern Yukon-Tanana Upland may correlate across the Tintina fault with unmetamorphosed counterparts in the Selwyn Basin (Murphy and Abbott, 1995). Volcanic-hosted (VMS) and sedimentary exhalative (sedex) massive sulfide occurrences are widely reported for these other areas (green-colored unit of fig. 1) but, as yet, have not been documented in the Alaskan part of the Yukon-Tanana Upland. Recent discoveries of VMS deposits in Devono-Mississippian metavolcanic rocks in the Finlayson Lake area of southeastern Yukon (Hunt, 1997) have increased the potential for finding VMS deposits in rocks of similar lithology and age in the Yukon-Tanana Upland of Alaska. Restoration of 450 km of early Tertiary dextral movement along the Tintina fault juxtaposes these two areas.

  20. Regional Geochemical Results from the Reanalysis of NURE Stream Sediment Samples - Eagle 3? Quadrangle, East-Central Alaska

    USGS Publications Warehouse

    Crock, J.G.; Briggs, P.H.; Gough, L.P.; Wanty, R.B.; Brown, Z.A.

    2007-01-01

    This report presents reconnaissance geochemical data for a cooperative study in the Fortymile Mining District, east-central Alaska, initiated in 1997. This study has been funded by the U.S. Geological Survey (USGS) Mineral Resources Program. Cooperative funds were provided from various State of Alaska sources through the Alaska Department of Natural Resources. Results presented here represent the initial reconnaissance phase for this multidisciplinary cooperative study. In this phase, 239 sediment samples from the Eagle 3? Quadrangle of east-central Alaska, which had been collected and analyzed for the U.S. Department of Energy's National Uranium Resource Evaluation program (NURE) of the 1970's (Hoffman and Buttleman, 1996; Smith, 1997), are reanalyzed by newer analytical methods that are more sensitive, accurate, and precise (Arbogast, 1996; Taggart, 2002). The main objectives for the reanalysis of these samples were to establish lower limits of determination for some elements and to confirm the NURE data as a reliable predictive reconnaissance tool for future studies in Alaska's Eagle 3? Quadrangle. This study has wide implications for using the archived NURE samples and data throughout Alaska for future studies.

  1. Shaded Relief with Height as Color, Kunlun fault, east-central Tibet

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These two images show exactly the same area, part of the Kunlun fault in northern Tibet. The image on the left was created using the best global topographic data set previously available, the U.S. Geological Survey's GTOPO30. In contrast, the much more detailed image on the right was generated with data from the Shuttle Radar Topography Mission, which collected enough measurements to map 80 percent of Earth's landmass at this level of precision.

    The area covered is the western part of the Kunlun fault, at the north edge of east-central Tibet. The sharp line marking the southern edge of the mountains, running left to right across the scene represents s strike-slip fault, much like California's San Andreas Fault, which is more than 1,000 kilometers (621 miles) long. The most recent earthquake on the Kunlun fault occurred on November 14, 2001. At a magnitude of 8.1, it produced a surface break over 350 kilometers (217 miles) long. Preliminary reports indicate a maximum offset of 7 meters (23 feet) in the central section of the break. This five-kilometer (three mile) high area is uninhabited by humans, so there was little damage reported, despite the large magnitude. Shuttle Radar Topography Mission maps of active faults in Tibet and other parts of the world provide geologists with a unique tool for determining how active a fault is and the probability of future large earthquakes on the fault. This is done by both measuring offsets in topographic features and using the SRTM digital map as a baseline for processing data from orbiting satellites using the techniques of radar interferometry. Based on geologic evidence, the Kunlun fault's long-term slip rate is believed to be about 11 millimeters per year (0.4 inches per year). The Kunlun fault and the Altyn Tagh fault, 400 kilometers (249 miles) to the north, are two major faults that help accommodate the ongoing collision between the Indian and Asian tectonic plates.

    In contrast with the wealth of detail

  2. Shaded Relief with Height as Color, Kunlun fault, east-central Tibet

    NASA Technical Reports Server (NTRS)

    2002-01-01

    These two images show exactly the same area, part of the Kunlun fault in northern Tibet. The image on the left was created using the best global topographic data set previously available, the U.S. Geological Survey's GTOPO30. In contrast, the much more detailed image on the right was generated with data from the Shuttle Radar Topography Mission, which collected enough measurements to map 80 percent of Earth's landmass at this level of precision.

    The area covered is the western part of the Kunlun fault, at the north edge of east-central Tibet. The sharp line marking the southern edge of the mountains, running left to right across the scene represents s strike-slip fault, much like California's San Andreas Fault, which is more than 1,000 kilometers (621 miles) long. The most recent earthquake on the Kunlun fault occurred on November 14, 2001. At a magnitude of 8.1, it produced a surface break over 350 kilometers (217 miles) long. Preliminary reports indicate a maximum offset of 7 meters (23 feet) in the central section of the break. This five-kilometer (three mile) high area is uninhabited by humans, so there was little damage reported, despite the large magnitude. Shuttle Radar Topography Mission maps of active faults in Tibet and other parts of the world provide geologists with a unique tool for determining how active a fault is and the probability of future large earthquakes on the fault. This is done by both measuring offsets in topographic features and using the SRTM digital map as a baseline for processing data from orbiting satellites using the techniques of radar interferometry. Based on geologic evidence, the Kunlun fault's long-term slip rate is believed to be about 11 millimeters per year (0.4 inches per year). The Kunlun fault and the Altyn Tagh fault, 400 kilometers (249 miles) to the north, are two major faults that help accommodate the ongoing collision between the Indian and Asian tectonic plates.

    In contrast with the wealth of detail

  3. Coeval dust accumulation minima in Greenland and East Central Europe over 31-23 ka

    NASA Astrophysics Data System (ADS)

    Újvári, Gábor; Stevens, Thomas; Varga, György; Kovács, János; Molnár, Mihály

    2016-04-01

    , together with the bulk loess median grain size (D50bulk) that is considered an integrated proxy of wind strength, dust source distance, aridity and vegetation cover. While an increase of dust flux and D50bulk with time is apparent, such a trend cannot be seen in the quartz grain size measures (D50quartz). This observation may imply that wind speeds were relatively constant in the studied time interval, while the turbulence of the flow may have been extremely varying (i.e. strong/rapid changes in the frequency/magnitude of dust storm events). A striking feature of the MAR record is that accumulation minima in the Dunaszekcsö record are synchronous with the Greenland Interstadials (GI-5.1 to GI-3). Subsequent Ca2+ minima in the NGRIP record at 26.22 and 25.02 ka (b2k) are also coeval with the MAR minima in the studied loess sequence. At the same time, these patterns are barely visible in the bulk and quartz grain size records. We speculate that the synchronous changes in the NGRIP Ca2+ and the Dunaszekcsö MAR records are results of millennial scale variations in the activity of Northern Hemisphere dust emitting regions shown in two archives from different environments. The very similar timing of MAR minima (and also some of the maxima) suggest a rapid aeolian system response in East Central Europe to abrupt climatic changes in the North Atlantic. Although such a synchronicity does not prove a Central European dust source to Greenland, it is consistent with this possibility. This study was supported by the OTKA PD-108639 grant and the Bolyai János Research Fellowship (both to GÚ). [1] Dansgaard, W., et al. (1993). Evidence for general instability of past climate from a 250-kyr ice-core record. Nature 364, 218-220. [2] Johnsen, S.J., et al. (1992). Irregular glacial interstadials recorded in a new Greenland ice core. Nature 359, 311-313. [3] Rasmussen, S.O., et al. (2014). A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three

  4. Coeval dust accumulation minima in Greenland and East Central Europe over 31-23 ka

    NASA Astrophysics Data System (ADS)

    Újvári, Gábor; Stevens, Thomas; Varga, György; Kovács, János; Molnár, Mihály

    2016-04-01

    , together with the bulk loess median grain size (D50bulk) that is considered an integrated proxy of wind strength, dust source distance, aridity and vegetation cover. While an increase of dust flux and D50bulk with time is apparent, such a trend cannot be seen in the quartz grain size measures (D50quartz). This observation may imply that wind speeds were relatively constant in the studied time interval, while the turbulence of the flow may have been extremely varying (i.e. strong/rapid changes in the frequency/magnitude of dust storm events). A striking feature of the MAR record is that accumulation minima in the Dunaszekcsö record are synchronous with the Greenland Interstadials (GI-5.1 to GI-3). Subsequent Ca2+ minima in the NGRIP record at 26.22 and 25.02 ka (b2k) are also coeval with the MAR minima in the studied loess sequence. At the same time, these patterns are barely visible in the bulk and quartz grain size records. We speculate that the synchronous changes in the NGRIP Ca2+ and the Dunaszekcsö MAR records are results of millennial scale variations in the activity of Northern Hemisphere dust emitting regions shown in two archives from different environments. The very similar timing of MAR minima (and also some of the maxima) suggest a rapid aeolian system response in East Central Europe to abrupt climatic changes in the North Atlantic. Although such a synchronicity does not prove a Central European dust source to Greenland, it is consistent with this possibility. This study was supported by the OTKA PD-108639 grant and the Bolyai János Research Fellowship (both to GÚ). [1] Dansgaard, W., et al. (1993). Evidence for general instability of past climate from a 250-kyr ice-core record. Nature 364, 218-220. [2] Johnsen, S.J., et al. (1992). Irregular glacial interstadials recorded in a new Greenland ice core. Nature 359, 311-313. [3] Rasmussen, S.O., et al. (2014). A stratigraphic framework for abrupt climatic changes during the Last Glacial period based on three

  5. Geologic map of the Mine Mountain area, Nevada Test Site, southern Nevada

    SciTech Connect

    Cashman, P.H.; Cole, J.C.

    1998-10-05

    The Mine Mountain area is a small range of hills on the west side of the central Yucca Flat basin on the Nevada Test Site, Nye County, Nevada. This map portrays the very complex relationships among the pre-Tertiary stratigraphic units of the region. Rocks and structures of the Mine Mountain area record the compounded effects of: (1) eastward-directed, foreland-vergent thrusting; (2) younger folds and thrusts formed by hinterland vergence in a general westerly direction; and (3) low-angle normal faulting formed by extension along a northeast-southwest trend. All of these structures are older than the oldest middle Miocene volcanic rocks that were deposited on the flanks of the Mine Mountain terrane. High-angle faults that post-date these volcanic rocks locally show displacements of several hundred meters, but do not strongly affect patterns in the pre-Tertiary rocks.

  6. Late Cretaceous extension in the hinterland of the Sevier thrust belt, northwestern Utah and southern Idaho

    SciTech Connect

    Wells, M.L.; Allmendinger, R.W. ); Dallmeyer, R.D. )

    1990-10-01

    Cover rocks of the Raft River metamorphic core complex, located in the Sevier belt hinterland, preserve a structural and metamorphic history that predates the middle Tertiary extension of the region. In the eastern Raft River Mountains, Cambrian( )-Permian rocks form two allochthons that occur in the hanging wall of the mid-Miocene Raft River detachment fault. Dramatically attenuated, metamorphosed Cambrian( )-Pennsylvanian strata of the lower allochthon yield Late Cretaceous muscovite {sup 40}Ar/{sup 39}Ar plateau ages (ca. 82-90 Ma) that are interpreted to date cooling during final stages of layer parallel extension. Devonian-Permian rocks exposed in the Black Pine Mountains underwent east-west extension ({approximately} 160%) associated with syntectonic growth of white mica along cleavage. {sup 40}Ar/{sup 39}Ar whole-rock spectra of associated slates also indicate a Late Cretaceous metamorphism. Together, field and {sup 40}Ar/{sup 39}Ar results suggest that Late Cretaceous extension occurred in the Sevier belt hinterland at the same time as shortening in the eastern foreland and at depth in the hinterland. Sufficient topography must have been present to drive upper-crustal extension in the eastern hinterland.

  7. Petrogenesis of the Barcroft pluton, northern White-Inyo Mountains, east-central California

    NASA Astrophysics Data System (ADS)

    Ernst, W. G.

    2013-03-01

    The White-Inyo Range lies within the regional transition from Paleozoic-Precambrian North American continental basement to outboard Mesozoic and younger accreted terranes and a superimposed Andean-type arc. In the central White Mountains, the metaluminous Barcroft granodiorite invaded a major NE-striking, SE-dipping high-angle reverse fault—the Barcroft break. Because it is a relatively isolated igneous body and is well exposed over an elevation range of 1,500-4,000 m, its thermal history and that of the surrounding superjacent section are clearer than those of nearly coeval, crowded plutons emplaced in the hotter Sierra Nevada belt. The Barcroft pluton was emplaced as a compositionally heterogeneous series of areally scattered melt pulses episodically injected over the approximate interval 167-161 Ma. The oldest dated rocks are relatively quartzofeldspathic, whereas the youngest is more ferromagnesian, suggesting progressive partial fusion of a relatively mafic protolith. Heavy rare earth-enriched zircons indicate that Barcroft melts were derived at mid-crustal depths from a previously emplaced metabasaltic protolith containing plagioclase but lacking garnet. Granodioritic magma genesis involved the possible mixing of mafic and felsic melts, as well as very minor assimilation of country rocks, but mainly by fractional fusion and crystallization. Bulk chemical, rare earth, and isotopic data suggest that analyzed Barcroft rocks are members of a single suite. Granodioritic rocks are slightly more magnetite-rich at higher elevations on the NE, nearer the roof of the pluton. Earlier thermobarometry chronicled cooling and re-equilibration of the Barcroft pluton from its margins inward, as well as from mid-crustal generation depths of ~25 km through ascent and stalling at ~10-12 km. Refractory phase assemblages crystallized along the pluton margins, whereas subsolidus minerals in the interior of the of body continued to exchange with upper crustal deuteric and

  8. Hinterland-to-foreland structural evolution of the base of the Himalayan metamorphic core, west Nepal

    NASA Astrophysics Data System (ADS)

    Braden, Z.; Godin, L.; Yakymchuk, C.; Kellett, D.; Cottle, J. M.

    2015-12-01

    The base of the Himalayan metamorphic core is a folded reverse-sense shear zone exposed extensively along its transport direction. In west Nepal, along-transport exposures show a transition in structural style from hinterland to foreland, and sampled quartzite and pelite show variations in thermobarometry, quartz crystallographic preferred orientation (CPO), monazite Th-Pb ages and 40Ar/39Ar thermochronology. In the hinterland region, the shear zone yields a deformation temperature gradient from > 700°C at the top of the shear zone down to 400°C at the base. Metamorphic grade also decreases downwards through the shear zone. Muscovite 40Ar/39Ar ages are ca. 6 Ma. In the transition zone separating hinterland and foreland on the north flank of the Karnali klippe, a comparable structural section yields a deformation temperature gradient that similarly decreases down structural level from ~700 to 500°C. Muscovite 40Ar/39Ar dating yield ca. 14-12 Ma cooling ages. In-situ monazite geochronology indicates prograde metamorphism at ca. 43-34 Ma and melt crystallization at ca. 26-18 Ma. In the foreland, deformation is not strictly brittle; CPO analyses on sheared quartzite on the south flank of the Karnali klippe suggest deformation temperatures decreasing from 500 to 400°C downwards through the shear zone. Muscovite from the foreland yields 40Ar/39Ar ages of ca. 17 Ma. Deformation temperatures decrease marginally from hinterland to foreland and structurally downward within the shear zone, and estimates suggest ductile deformation prevails well into the foreland. Hinterland 40Ar/39Ar muscovite ages in west Nepal are anomalously young, and are possibly related to recent exhumation due to the SE-propagating mid-Miocene Gurla Mandhata-Humla system. Alternatively, they could be linked to the activation of a young duplex in the footwall of the Himalayan metamorphic core due to along-strike variation in geometry of the Main Himalayan thrust ramp.

  9. Exposure and effects of perfluoroalkyl compounds on tree swallows nesting at Lake Johanna in east central Minnesota, USA.

    PubMed

    Custer, Christine M; Custer, Thomas W; Schoenfuss, Heiko L; Poganski, Beth H; Solem, Laura

    2012-07-01

    Tree swallow (Tachycineta bicolor) samples were collected at a reference lake and a nearby lake (Lake Johanna) in east central Minnesota, USA contaminated with perfluorinated carboxylic and sulfonic acids. Tissues were analyzed for a suite of 13 perfluoroalkyl compounds (PFCs) to quantify exposure and to determine if there was an association between egg concentrations of PFCs and reproductive success of tree swallows. Concentrations of perfluoroocatane sulfonate (PFOS) were elevated in all tree swallow tissues from Lake Johanna compared to tissues collected at the reference lake. Other PFCs, except for two, were elevated in blood plasma at Lake Johanna compared to the reference lake. PFOS was the dominant PFC (>75%) at Lake Johanna, but accounted for <50% of total PFCs at the reference lake. There was a negative association between concentrations of PFOS in eggs and hatching success. Reduced hatching success was associated with PFOS levels as low as 150ng/g wet weight. PMID:21296656

  10. CHARACTER AND REGIONAL SIGNIFICANCE OF GREAT FALLS TECTONIC ZONE, EAST-CENTRAL IDAHO AND WEST-CENTRAL MONTANA.

    USGS Publications Warehouse

    O'Neill, J. Michael; Lopez, David A.

    1985-01-01

    The Great Falls tectonic zone, here named, is a belt of diverse northeast-trending geologic features that can be traced from the Idaho batholith in the Cordilleran miogeocline, across thrust-belt structures and basement rocks of west-central and southwestern Montana, through cratonic rocks of central Montana, and into southwestern-most Saskatchewan, Canada. Geologic mapping in east-central Idaho and west-central Montana has outlined a continuous zone of high-angle faults and shear zones. Recurrent fault movement in this zone and strong structural control over igneous intrusion suggest a fundamental tectonic feature that has influenced the tectonic development of the Idaho-Montana area from a least middle Proterozoic time to the present. Refs.

  11. Natural fractures and lineaments of the east-central Greater Green river basin. Topical report, May 1992-August 1995

    SciTech Connect

    Jaworowski, C.; Christiansen, G.E.; Grout, M.A.; Heasler, H.P.; Iverson, W.P.

    1995-08-01

    This topical report addresses the relationship of natural fractures and lineaments to hydrocarbon production of the east-central Greater Green River Basin. The tight gas sands of the Cretaceous Mesaverde Formation are the primary focus of this work. IER and USGS researchers have (1) demonstrated that east-northeast and northeast-trending regional fractures and lineaments are important to hydrocarbon production; (2) recognized the east-northeast regional joint set near two horizontal wells (Champlin 254 Amoco B 2-H and Champlin 320 C-1A-H) in the Washankie and Great Divide basins, respectively; (3) related Cretaceous Almond Formation thickness and facies to northeast-trending faults; (4) developed a program to automatically derive lineaments from small linear features; (5) associated oil and gas production data with east-northeast and northeast-trending lineaments and linear features; and (6) digitally compared lineaments with potentiometric maps of the Mesaverde and Frontier formations.

  12. High-pressure amphibolite facies dynamic metamorphism and the Mesozoic tectonic evolution of an ancient continental margin, east- central Alaska

    USGS Publications Warehouse

    Dusel-Bacon, C.; Hansen, V.L.; Scala, J.A.

    1995-01-01

    Ductilely deformed amphibolite facies tectonites comprise two adjacent terranes in east-central Alaska: the northern, structurally higher Taylor Mountain terrane and the southern, structurally lower Lake George subterrane of the Yukon-Tanana terrane. The pressure, temperature, kinematic and age data are interpreted to indicate that the metamorphism of the Taylor Mountain terrane and Lake George subterrane took place during different phases of a latest Palaeozoic through early Mesozoic shortening episode resulting from closure of an ocean basin now represented by klippen of the Seventymile-Slide Mountain terrane. High- to intermediate-pressure metamorphism of the Taylor Mountain terrane took place within a SW-dipping (present-day coordinates) subduction system. High- to intermediate-pressure metamorphism of the Lake George subterrane and the structural contact zone occurred during NW-directed overthrusting of the Taylor Mountain, Seventymile-Slide Mountain and Nisutlin terranes, and imbrication of the continental margin in Jurassic time. -from Authors

  13. Exposure and effects of perfluoroalkyl compounds on tree swallows nesting at Lake Johanna in east central Minnesota, USA

    USGS Publications Warehouse

    Custer, Christine M.; Custer, Thomas W.; Schoenfuss, Heiko L.; Poganski, Beth H.; Solem, Laura

    2012-01-01

    Tree swallow (Tachycineta bicolor) samples were collected at a reference lake and a nearby lake (Lake Johanna) in east central Minnesota, USA contaminated with perfluorinated carboxylic and sulfonic acids. Tissues were analyzed for a suite of 13 perfluoroalkyl compounds (PFCs) to quantify exposure and to determine if there was an association between egg concentrations of PFCs and reproductive success of tree swallows. Concentrations of perfluoroocatane sulfonate (PFOS) were elevated in all tree swallow tissues from Lake Johanna compared to tissues collected at the reference lake. Other PFCs, except for two, were elevated in blood plasma at Lake Johanna compared to the reference lake. PFOS was the dominant PFC (>75%) at Lake Johanna, but accounted for <50% of total PFCs at the reference lake. There was a negative association between concentrations of PFOS in eggs and hatching success. Reduced hatching success was associated with PFOS levels as low as 150 ng/g wet weight.

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

    USGS Publications Warehouse

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

    2015-01-01

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

  15. Geologic map of the Alligator Ridge area, including the Buck Mountain East and Mooney Basin Summit quadrangles and parts of the Sunshine Well NE and Long Valley Slough quadrangles, White Pine County, Nevada

    USGS Publications Warehouse

    Nutt, Constance J.

    2000-01-01

    Data set describes the geology of Paleozoic through Quaternary units in the Alligator Ridge area, which hosts disseminated gold deposits. These digital files were used to create the 1:24,000-scale geologic map of the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, east-central Nevada.

  16. Quaternary glacial and post-glacial depositional history associated with the Green Bay lobe, east-central Wisconsin

    SciTech Connect

    Thieme, L.D.; Smith, G.L. . Dept. of Geology)

    1993-03-01

    Multiple layers of peat and wood fragments indicate that Quaternary glaciation of the east-central region of Wisconsin was punctuated by at least two interglacial periods. Till, outwash, and glaciolacustrine deposits suggest that deposition took place in alternating glacial and non-glacial environments due to oscillations in the position of the Green Bay Lobe terminus. The data for this study consists of 36 auger borings, 70 geologic logs and 100 well-construction reports from water wells. Nine vibracores were taken at the northern margin of Lake Winnebago in order to document in detail the post-glacial history of Glacial Lake Oshkosh/Lake Winnebago. Local bedrock consists of limestones and dolomites of the Middle Ordovician Sinnipee Group. Bedrock elevations range from 211--237 m; bedding dips regionally to the southeast at 1--2 degrees. Bedrock is overlain by a 3--13 m-thick layer of alternating red clay and gray silty-clay (basal Kewaunee Formation ) perhaps deposited in a proglacial lake. These sediments are overlain by apeat/wood layer indicating marsh deposition. This peat/wood layer is overlain by more proglacial lake sediment, 3--10 m of gray brown clay to silty-clay. A second peat/wood layer overlies the gray/brown sediment and may correlate with the Two Creeks buried forest bed. The uppermost unit consists of 2--3 m red silty-clay till (Middle Inlet Member of the Kewaunee Formation). Along the northern margin of present-day Lake Winnebago, red silty-clay is overlain by silty-sand deposited by Glacial Lake Oshkosh. Future work includes obtaining radiocarbon dates from buried peat/wood layers to verify these tentative correlations between east-central Wisconsin and the Lake Michigan Basin.

  17. Organochlorine insecticide residues and PCBs in tissues of woodcock, mourning doves, and robins from east-central, Illinois, 1978-79

    SciTech Connect

    Edwards, W.R.; Duzan, R.E.; Siemers, R.J.

    1983-10-01

    Reported here are levels in ppm of heptachlor, heptachlor epoxide, dieldrin, p,p'-DDE (DDE), and PCB residues assayed in muscle, heart, liver, brain, and fatty tissues of woodcock (Philohelo minor), mourning doves (Zenaidura macroura), and robins (Turdus migratorium) from east-central Illinois in 1978 and 1979.

  18. Low-Income Rural People in East Central Arkansas Face Roadblocks to Jobs. Arkansas Agricultural Experiment Station, Agricultural Economic Report No. 290.

    ERIC Educational Resources Information Center

    Davis, Richard N.; And Others

    From 1967 to 1971, a total of 742 low income, rural people in east central Arkansas were trained with funds provided by the Economic Opportunity Act (Title III-B). A total of 133 of these people were interviewed and divided into the following subgroups for purposes of comparison; (1) 74 respondents (46 blacks and 28 whites) who had been and…

  19. Advanced power assessment for Czech lignite, Task 3.6, Part 2. The 2nd international conference on energy and environment: Transitions in East Central Europe

    SciTech Connect

    Sondreal, E.A.; Mann, M.D.; Weber, G.W.; Young, B.C.

    1995-12-01

    On November 1-5, 1994, the Energy & Environmental Research Center (EERC) and Power Research Institute of Prague cosponsored their second conference since 1991 in the Czech Republic, entitled ``Energy and Environment: Transitions in East Central Europe.`` This conference was a continuation of the EERC`s joint commitment, initiated in 1190, to facilitate solutions to short- and long-term energy and environmental problems in East Central Europe. Production of energy from coal in an environmentally acceptable manner is a critical issue facing East Central Europe, because the region continues to rely on coal as its primary energy source. The goal of the conference was to develop partnerships between industry, government, and the research community in East Central Europe and the United States to solve energy and environmental issues in a manner that fosters economic development. Among the topics addressed at the conference were: conventional and advanced energy generation systems; economic operation of energy systems; air pollution controls; power system retrofitting and repowering, financing options; regulatory issues; energy resource options; waste utilization and disposal; and long-range environmental issues. Selected papers in the proceedings have been processed separately for inclusion in the Energy Science and Technology database.

  20. The Zagros hinterland fold-and-thrust belt in-sequence thrusting, Iran

    NASA Astrophysics Data System (ADS)

    Sarkarinejad, Khalil; Ghanbarian, Mohammad Ali

    2014-05-01

    The collision of the Iranian microcontinent with the Afro-Arabian continent resulted in the deformation of the Zagros orogenic belt. The foreland of this belt in the Persian Gulf and Arabian platform has been investigated for its petroleum and gas resource potentials, but the Zagros hinterland is poorly investigated and our knowledge about its deformation is much less than other parts of this orogen. Therefore, this work presents a new geological map, stratigraphic column and two detailed geological cross sections. This study indicates the presence of a hinterland fold-and-thrust belt on northeastern side of the Zagros orogenic core that consists of in-sequence thrusting and basement involvement in this important part of the Zagros hinterland. The in-sequence thrusting resulted in first- and second-order duplex systems, Mode I fault-bend folding, fault-propagation folding and asymmetric detachment folding which indicate close relationships between folding and thrusting. Study of fault-bend folds shows that layer-parallel simple shear has the same role in the southeastern and northwestern parts of the study area (αe = 23.4 ± 9.1°). A major lateral ramp in the basement beneath the Talaee plain with about one kilometer of vertical offset formed parallel to the SW movement direction and perpendicular to the major folding and thrusting.

  1. Risk factors associated with the presence of Varroa destructor in honey bee colonies from east-central Argentina.

    PubMed

    Giacobino, A; Bulacio Cagnolo, N; Merke, J; Orellano, E; Bertozzi, E; Masciangelo, G; Pietronave, H; Salto, C; Signorini, M

    2014-08-01

    Varroa destructor is considered one of the major threats for worldwide apiculture. Damage caused by varroa mite includes body weight loss, malformation and weakening of the bees. It was also suggested as the main cause associated with colony winter mortality and as an important vector for several honey bee viruses. Little is known about multiple factors and their interaction affecting V. destructor prevalence in apiaries from South America. The aim of this study was to identify risk factors associated with V. destructor prevalence in east-central Argentina. Parasitic mite infestation level and colony strength measures were evaluated in 63 apiaries distributed in 4 different regions in east-central Argentina in a cross sectional study. Data regarding management practices in each apiary were collected by means of a questionnaire. A mixed-effects logistic regression model was constructed to associate management variables with the risk of achieving mite infestation higher than 3%. Colonies owned by beekeepers who indicated that they did not monitor colonies after mite treatment (OR=2.305; 95% CI: 0.944-5.629) nor disinfect hives woodenware material (OR=2.722; 95% CI: 1.380-5.565) were associated with an increased risk of presenting high intensity infestation with V. destructor (>3%). On the other hand, beekeepers who reported replacing more than 50% of the queens in their operation (OR=0.305; 95% CI: 0.107-0.872), feeding colonies protein substitute containing natural pollen (OR=0.348; 95% CI: 0.129-0.941) and feeding colonies High Fructose Corn Syrup (HFCS) (OR=0.108; 95% CI: 0.032-0.364), had colonies that were less likely to have V. destructor infestations above 3%, than beekeepers who did not report using these management practices. Further research should be conducted considering that certain management practices were associated to mite infestation level in order to improve the sanitary condition in the colonies. Epidemiological studies provide key information to

  2. Hydrogeology of and potential mining impacts on strippable lignite areas in the Denver Aquifer, east-central Colorado

    USGS Publications Warehouse

    Driver, N.E.; Williams, R.S.

    1986-01-01

    This study describes the hydrogeology of and potential impacts of mining on strippable lignite areas in the Denver aquifer in the east-central Colorado plains. Strippable lignitic coal seams , 20 to 60 ft thick, are present in the Denver Formation. The Denver aquifer, the saturated part of the Denver Formation, is likely to be affected locally by surface mining of lignite. Transmissivity of the aquifer in the study area ranges from 145 to 1,000 mg/L to the northeast in the study area as, hydraulic head decreases from 6,600 to 5,400 ft. Distance-drawdown curves show the extent of water level drawdown near a dewatered surface mine. After reclamation of the lignite mine pit, flow through the lignite spoil pile may increase the dissolved solids concentrations in the Denver aquifer. This increase could occur, because, as water from rain and overland flow percolates through the newly-exposed rock surfaces in the spoil material, minerals from the overburden can be dissolved in the water, which then joins with water from the aquifer. This increase could locally change streams, springs, and alluvial and bedrock aquifers. (USGS)

  3. Novel early flood warning in the Huaihe River basin in east-central China using the TIGGE database

    NASA Astrophysics Data System (ADS)

    He, Y.; Cloke, H.; Li, Z.; Wetterhall, F.; Pappenberger, F.

    2009-04-01

    Flooding is a wide spread and devastating natural disaster worldwide. Floods that took place in the last decade in China were ranked the worst amongst recorded floods worldwide in terms of the number of human fatalities and economic losses (Munich Re-Insurance). Rapid economic development and population expansion into low lying flood plains has worsened the situation. The last decade has seen an increase in flood preparedness across all levels of society in China. Current conventional flood prediction systems in China are neither suited to the perceptible climate variability nor the rapid pace of urbanization sweeping the country. Flood prediction systems from short-term (a few hours) to medium-term (a few days) need to be revisited and adapted to changing socio-economic and hydro-climatic realities. The latest technology requires implementation of multiple numerical weather prediction systems. The availability of a number of global ensemble weather prediction systems through the ‘THORPEX Interactive Grand Global Ensemble' (TIGGE) offers a good opportunity for an effective state-of-the-art early forecasting system. A prototype of a Novel Flood Early Warning System (NEWS) using the TIGGE database is tested in the Huai River basin located in east-central China. It is the first early flood warning system in China that uses the massive TIGGE database cascaded with river catchment models, the Xinanjiang model and a 1-D hydraulic model, to predict river discharge and flood inundation. Results from selected flood events will be presented.

  4. Hydrogeology and water-quality conditions at the City of Olathe Landfill, east-central Kansas, 1990-93

    USGS Publications Warehouse

    Rasmussen, P.P.; Shockley, J.C.; Hargadine, D.A.

    1994-01-01

    Water quality at the City of Olathe Landfill in east-central Kansas was examined in relation to hydrogeologic conditions to help determine the effects of the landfill on shallow ground water. This study focused on the Wyandotte and Plattsburg Limestones underlying the landfill. The Wyandotte Limestone underlies the entire landfill, whereas the overlying Plattsburg Limestone crops out within the landffll boundaries. Little Cedar Creek, an unnamed tributary, and a pond are located in the landfill. Water samples from seven monitoring wells and five surface-water sites in the vicinity of the City of Olathe Landfill were collected for analysis of inorganic and organic constituents. The inorganic constituents in the ground water that are most affected in the vicinity of the landfill are calcium, magnesium, sodium, bicarbonate, ammonia, barium, iron, and manganese. The dissolved- organic-carbon concentration at a seep flowing from the Plattsburg Limestone was 1,400 milligrams per liter, indicating that the landfill is affecting the water quality near the seep. Benzene was detected in all of the water samples, and the largest concentration was in a sample collected upgradient of the landfill. The benzene concentration exceeded the U.S. Environmental Protection Agency's Maximum Contaminant Level (0.005 milligram per liter) for drinking-water supplies. Six of the eight specific organic compounds detected were found in a water sample collected from the Plattsburg Limestone immediately downgradient of the landfill. No organic compoands, except benzene, were detected in samples collected from the Wyandotte Limestone downgradient of the landfill.

  5. Community knowledge and acceptance of larviciding for malaria control in a rural district of east-central Tanzania.

    PubMed

    Mboera, Leonard E G; Kramer, Randall A; Miranda, Marie Lynn; Kilima, Stella P; Shayo, Elizabeth H; Lesser, Adriane

    2014-05-01

    The use of microbial larvicides, a form of larval source management, is a less commonly used malaria control intervention that nonetheless has significant potential as a component of an integrated vector management strategy. We evaluated community acceptability of larviciding in a rural district in east-central Tanzania using data from 962 household surveys, 12 focus group discussions, and 24 in-depth interviews. Most survey respondents trusted in the safety (73.1%) and efficacy of larviciding, both with regards to mosquito control (92.3%) and to reduce malaria infection risk (91.9%). Probing these perceptions using a Likert scale provides a more detailed picture. Focus group participants and key informants were also receptive to larviciding, but stressed the importance of sensitization before its implementation. Overall, 73.4% of survey respondents expressed a willingness to make a nominal household contribution to a larviciding program, a proportion which decreased as the proposed contribution increased. The lower-bound mean willingness to pay is estimated at 2,934 Tanzanian Shillings (approximately US$1.76) per three month period. We present a multivariate probit regression analysis examining factors associated with willingness to pay. Overall, our findings point to a receptive environment in a rural setting in Tanzania for the use of microbial larvicides in malaria control. PMID:24830448

  6. Ovarian development and ovipositional preference of the western corn rootworm (Coleoptera: Chrysomelidae) variant in east central Illinois.

    PubMed

    Rondon, Silvia I; Gray, Michael E

    2004-04-01

    The rotation of maize, Zea mays L., and soybean, Glycine max (L.) Merr., has been the traditional cultural tactic to manage the western corn rootworm, Diabrotica virgifera virgifera LeConte, in the Corn Belt. The reduced effectiveness of this rotation as a pest management tool in east central Illinois, northern Indiana, and southern Michigan can be explained by the shift in the ovipositional behavior of the new variant of western corn rootworm. The objective of this study was to evaluate the influence of maize, soybean, oat, Avena sativa L., stubble, and alfalfa, Medicago sativa L., on the ovarian development and ovipositional preferences of the variant western corn rootworm. Field research was conducted near Urbana, IL, during 1998-2000. Gravid females were present throughout the season in all crops, and due to the prolonged period in which western corn rootworm females can lay eggs, none of the crops were immune from oviposition. Results indicated that the western corn rootworm variant oviposits in maize, soybean, oat stubble, and alfalfa In 1998 and 1999, maize was the preferred oviposition site among crops; however, in 2000, maize, soybean, and oat stubble treatments had similar densities of western corn rootworm eggs. Lack of oviposition preference of the western corn rootworm variant demonstrated in this experiment represents a reasonable explanation of why the effectiveness of the rotation strategy to control western corn rootworm has diminished. PMID:15154460

  7. Deep-seated gravitational slope deformations near the Trans-Alaska Pipeline, east-central Alaska Range, Alaska, USA

    NASA Astrophysics Data System (ADS)

    Newman, S. D.; Clague, J. J.; Rabus, B.; Stead, D.

    2013-12-01

    Multiple, active, deep-seated gravitational slope deformations (DSGSD) are present near the Trans-Alaska Pipeline and Richardson Highway in the east-central Alaska Range, Alaska, USA. We documented spatial and temporal variations in rates of surface movement of the DSGSDs between 2003 and 2011 using RADARSAT-1 and RADARSAT-2 D-InSAR images. Deformation rates exceed 10 cm/month over very large areas (>1 km2) of many rock slopes. Recent climatic change and strong seismic shaking, especially during the 2002 M 7.9 Denali Fault earthquake, appear to have exacerbated slope deformation. We also mapped DSGSD geological and morphological characteristics using field- and GIS-based methods, and constructed a conceptual 2D distinct-element numerical model of one of the DSGSDs. Preliminary results indicate that large-scale buckling or kink-band slumping may be occurring. The DSGSDs are capable of generating long-runout landslides that might impact the Trans-Alaska Pipeline and Richardson Highway. They could also block tributary valleys, thereby impounding lakes that might drain suddenly. Wrapped 24-day RADARSAT-2 descending spotlight interferogram showing deformation north of Fels Glacier. The interferogram is partially transparent and is overlaid on a 2009 WorldView-1 panchromatic image. Acquisition interval: August 2 - August 26, 2011. UTM Zone 6N.

  8. Bacterial production of methane and its influence on ground-water chemistry in east-central Texas aquifers

    NASA Astrophysics Data System (ADS)

    Grossman, Ethan L.; Coffman, B. Keith; Fritz, Steven J.; Wada, Hideki

    1989-06-01

    Geochemical and isotopic data for methane and ground water indicate that gaseous hydrocarbons in Eocene aquifers in east-central Texas form by bacterial processes. The δ13C values of methane from five wells in the clay-rich Yegua and Cook Mountain Formations range from -71‰ to -62‰. Methane from ten wells in the cleaner sands of the Sparta and Queen City Formations have δ13C values between -57‰ and -53‰. The carbon isotopic difference between methanes from the Yegua and Sparta aquifers is comparable to the isotopic difference in sedimentary organic matter from outcrops of the units, suggesting substrate control on the δ13C of bacterial methane. Hydrogen isotopic compositions of methane from the aquifers are similar, averaging -181‰. This high value suggests methane production predominantly by CO2 reduction. The δ13C of dissolved inorganic carbon (DIC) in high bicarbonate waters increases from about -20‰ to 0‰ with increasing DIC. Mass-balance calculations indicate that the DIC added to the ground water has δ;13C values as high as 10‰. This 13C-enriched carbon is predominantly derived from CO2 production by fermentation and anaerobic oxidation reactions combined with CO2 consumption by CO2 reduction. This process is responsible for high bicarbonate contents in these and probably other Gulf Coast ground waters.

  9. Rhyolitic calderas of the Yukon-Tanana Terrane, east central Alaska: volcanic remnants of a mid-Cretaceous magmatic arc

    USGS Publications Warehouse

    Bacon, C.R.; Foster, H.L.; Smith, James G.

    1990-01-01

    Four large but poorly exposed rhyolitic calderas are present in the Yukon-Tanana terrane (YTT) in east central Alaska. At least two are mid-Cretaceous in age (~93 Ma). Similar volcanic rocks, the South Fork Volcanics, occur northeast of the Tintina fault in Yukon Territory. Evidence for the calderas consists of thick deposits of devitrified crystal- and lithic-rich densely welded tuff, interpreted as caldera fill, associated with lava domes or shallow intrusive rocks. Coeval outflow sheets have been largely stripped by erosion. The calderas are preserved within a northeast trending depression extending across the axis of the elongate mid-Cretaceous plutonic province. Trace element abundances in andesites and rhyolites associated with the caldera structures are similar to those of volcanic and plutonic rocks of subduction-related magmatic arcs developed on continental crust and thus are suggestive of formation in such an environment. Late Cretaceous and early Tertiary igneous rocks in the YTT near the calderas are interpreted to have been emplaced in a more extensional setting when the subduction-related magmatic front was farther oceanward. -Authors

  10. Crustal structure of southwestern Montana and east-central Idaho: Results of a reversed seismic refraction line

    NASA Astrophysics Data System (ADS)

    Sheriff, Steven D.; Stickney, Michael C.

    1984-04-01

    On October 20, 1982, we collected seismic refraction data on a 250 km line segment between Butte, Montana and Challis, Idaho. These data are from two open pit mine blasts; one at Anaconda Minerals Companys' southeast Berkely pit and the other at Cyprus Mines Corporations' Thompson creek mine. Eight of our ten recorders wrote clear records of both blasts with measured travel times accurate to +/-0.2 seconds. We supplemented these data with data from permanent stations in the Butte area. The Pg (crustal) velocity is 5.8 km/s to the southwest and 6.0 km/s to the northeast. The Pn (mantle) velocity is 7.9 km/s to the northeast and 8.1 km/s to the southwest; total travel-times are equal. The S-wave velocity in the crust is about 3.5 km/s. The symmetry of the travel-time results, with their intersection within one kilometer of the midpoint between the pit blasts, strongly suggests the refraction line overlies a horizontal Moho or parallels the strike line of a dipping Moho surface. These data indicate the crust in southwestern Montana and east-central Idaho is approximately 33 km thick. Contrasting tectonic processes, compression and thickening during the Laramide orogeny with extension and thinning since the Paleocene, resulted in a crust with slightly less than normal thickness.

  11. Groundwater flow and water budget in the surficial and Floridan aquifer systems in east-central Florida

    USGS Publications Warehouse

    Sepulveda, Nicasio; Tiedeman, Claire R.; O'Reilly, Andrew M.; Davis, Jeffrey B.; Burger, Patrick

    2012-01-01

    A numerical transient model of the surficial and Floridan aquifer systems in east-central Florida was developed to (1) increase the understanding of water exchanges between the surficial and the Floridan aquifer systems, (2) assess the recharge rates to the surficial aquifer system from infiltration through the unsaturated zone and (3) obtain a simulation tool that could be used by water-resource managers to assess the impact of changes in groundwater withdrawals on spring flows and on the potentiometric surfaces of the hydrogeologic units composing the Floridan aquifer system. The hydrogeology of east-central Florida was evaluated and used to develop and calibrate the groundwater flow model, which simulates the regional fresh groundwater flow system. The U.S. Geological Survey three-dimensional groundwater flow model, MODFLOW-2005, was used to simulate transient groundwater flow in the surficial, intermediate, and Floridan aquifer systems from 1995 to 2006. The East-Central Florida Transient model encompasses an actively simulated area of about 9,000 square miles. Although the model includes surficial processes-rainfall, irrigation, evapotranspiration (ET), runoff, infiltration, lake water levels, and stream water levels and flows-its primary purpose is to characterize and refine the understanding of groundwater flow in the Floridan aquifer system. Model-independent estimates of the partitioning of rainfall into ET, streamflow, and aquifer recharge are provided from a water-budget analysis of the surficial aquifer system. The interaction of the groundwater flow system with the surface environment was simulated using the Green-Ampt infiltration method and the MODFLOW-2005 Unsaturated-Zone Flow, Lake, and Streamflow-Routing Packages. The model is intended to simulate the part of the groundwater system that contains freshwater. The bottom and lateral boundaries of the model were established at the estimated depths where the chloride concentration is 5,000 milligrams

  12. Groundwater flow and water budget in the surficial and Floridan aquifer systems in east-central Florida

    USGS Publications Warehouse

    Sepulveda, Nicasio; Tiedeman, Claire R.; O'Reilly, Andrew M.; Davis, Jeffery B.; Burger, Patrick

    2012-01-01

    A numerical transient model of the surficial and Floridan aquifer systems in east-central Florida was developed to (1) increase the understanding of water exchanges between the surficial and the Floridan aquifer systems, (2) assess the recharge rates to the surficial aquifer system from infiltration through the unsaturated zone and (3) obtain a simulation tool that could be used by water-resource managers to assess the impact of changes in groundwater withdrawals on spring flows and on the potentiometric surfaces of the hydrogeologic units composing the Floridan aquifer system. The hydrogeology of east-central Florida was evaluated and used to develop and calibrate the groundwater flow model, which simulates the regional fresh groundwater flow system. The U.S. Geological Survey three-dimensional groundwater flow model, MODFLOW-2005, was used to simulate transient groundwater flow in the surficial, intermediate, and Floridan aquifer systems from 1995 to 2006. The east-central Florida transient model encompasses an actively simulated area of about 9,000 square miles. Although the model includes surficial processes-rainfall, irrigation, evapotranspiration, runoff, infiltration, lake water levels, and stream water levels and flows-its primary purpose is to characterize and refine the understanding of groundwater flow in the Floridan aquifer system. Model-independent estimates of the partitioning of rainfall into evapotranspiration, streamflow, and aquifer recharge are provided from a water-budget analysis of the surficial aquifer system. The interaction of the groundwater flow system with the surface environment was simulated using the Green-Ampt infiltration method and the MODFLOW-2005 Unsaturated-Zone Flow, Lake, and Streamflow-Routing Packages. The model is intended to simulate the part of the groundwater system that contains freshwater. The bottom and lateral boundaries of the model were established at the estimated depths where the chloride concentration is 5

  13. Biogeochemical characterization of an undisturbed highly acidic, metal-rich bryophyte habitat, east-central Alaska, U.S.A.

    USGS Publications Warehouse

    Gough, L.P.; Eppinger, R.G.; Briggs, P.H.; Giles, S.

    2006-01-01

    We report on the geochemistry of soil and bryophyte-laden sediment and on the biogeochemistry of willows growing in an undisturbed volcanogenic massive sulfide deposit in the Alaska Range ecoregion of east-central Alaska. We also describe an unusual bryophyte assemblage found growing in the acidic metal-rich waters that drain the area. Ferricrete-cemented silty alluvial sediments within seeps and streams are covered with the liverwort Gymnocolea inflata whereas the mosses Polytrichum commune and P. juniperinum inhabit the area adjacent to the water and within the splash zone. Both the liverwort-encrusted sediment and Polytrichum thalli have high concentrations of major and trace metal cations (e.g., Al, As, Cu, Fe, Hg, La, Mn, Pb, and Zn). Soils in the area do not reflect the geochemical signature of the mineral deposit and we postulate they are influenced by the chemistry of eolian sediments derived from outside the deposit area. The willow, Salix pulchra, growing mostly within and adjacent to the larger streams, has much higher concentrations of Al, As, Cd, Cr, Fe, La, Pb, and Zn when compared to the same species collected in non-mineralized areas of Alaska. The Cd levels are especially high and are shown to exceed, by an order of magnitude, levels demonstrated to be toxic to ptarmigan in Colorado. Willow, growing in this naturally occurring metal-rich Red Mountain alteration zone, may adversely affect the health of browsing animals. ?? 2006 Regents of the University of Colorado.

  14. The hydrologic effects of intense groundwater pumpage in east-central Hillsborough County, Florida, U.S.A.

    NASA Astrophysics Data System (ADS)

    Bengtsson, T. O.

    1989-07-01

    Well problems, water shortages, local flooding, and induced sinkholes have been periodic problems for residents in east-central Hillsborough County, Florida. This agricultural area has experienced dramatic short-term water-level declines in the Floridan aquifer from seasonal groundwater withdrawals. The sudden declines in the potentiometric surface have been caused from intense irrigation pumpage, primarily for frost and freeze protection and fruit setting. Citrus and strawberry crops are protected from occasional freezes by the application of warm groundwater to maintain minimum soil temperatures of 32°F(0°C). Local residents with inadequately constructed wells lose their source of water when the potentiometric surface is lowered to depths where their wells do not function. Some residents have lost their water supply for a week or more, and many have incurred damage to their pumps. The drawdown of the potentiometric surface in some areas has induced sinkholes causing property damage for some residents and concern for others. In addition, the high application rates for frost and freeze irrigation have created run-off problems resulting in local flooding to some residents. Fortunately, there has been no damage to resident homes from the flooding or sinkholes. This report summarizes the area's hydrogeology, and the consequences of heavy freeze irrigation. A finite-difference, numerical model is used to quantify the regional impacts to the potentiometric surface of the Floridan aquifer from estimated irrigation pumpage. Management recommendations for alleviating the problems are also discussed in the report.

  15. Simulated effects of surface coal mining and agriculture on dissolved solids in the Redwater River, east-central Montana

    USGS Publications Warehouse

    Ferreira, R.F.; Lambing, J.H.

    1985-01-01

    Dissolved solids concentrations in five reaches of the Redwater River in east-central Montana were simulated to evaluate the effects of surface coal mining and agriculture. A mass-balance model of streamflow and dissolved solids load developed for the Tongue River in southeastern Montana was modified and applied to the Redwater River. Mined acreages, dissolved solids concentrations in mined spoils, and irrigated acreage can be varied in the model to study relative changes in the dissolved solids concentration in consecutive reaches of the river. Because of extreme variability and a limited amount of data, the model was not consecutively validated. Simulated mean and median monthly mean streamflows and consistently larger than those calculated from streamflow records. Simulated mean and median monthly mean dissolved solids loads also are consistently larger than regression-derived values. These discrepancies probably result from extremely variable streamflow, overestimates of streamflow from ungaged tributaries, and weak correlations between streamflow and dissolved solids concentrations. The largest increases in simulated dissolved solids concentrations from mining and agriculture occur from September through January because of smaller streamflows and dissolved solids loads. Different combinations of agriculture and mining under mean flow conditions resulted in cumulative percentage increases of dissolved solids concentrations of less than 5% for mining and less than 2% for agriculture. (USGS)

  16. Community Knowledge and Acceptance of Larviciding for Malaria Control in a Rural District of East-Central Tanzania

    PubMed Central

    Mboera, Leonard E. G.; Kramer, Randall A.; Miranda, Marie Lynn; Kilima, Stella P.; Shayo, Elizabeth H.; Lesser, Adriane

    2014-01-01

    The use of microbial larvicides, a form of larval source management, is a less commonly used malaria control intervention that nonetheless has significant potential as a component of an integrated vector management strategy. We evaluated community acceptability of larviciding in a rural district in east-central Tanzania using data from 962 household surveys, 12 focus group discussions, and 24 in-depth interviews. Most survey respondents trusted in the safety (73.1%) and efficacy of larviciding, both with regards to mosquito control (92.3%) and to reduce malaria infection risk (91.9%). Probing these perceptions using a Likert scale provides a more detailed picture. Focus group participants and key informants were also receptive to larviciding, but stressed the importance of sensitization before its implementation. Overall, 73.4% of survey respondents expressed a willingness to make a nominal household contribution to a larviciding program, a proportion which decreased as the proposed contribution increased. The lower-bound mean willingness to pay is estimated at 2,934 Tanzanian Shillings (approximately US$1.76) per three month period. We present a multivariate probit regression analysis examining factors associated with willingness to pay. Overall, our findings point to a receptive environment in a rural setting in Tanzania for the use of microbial larvicides in malaria control. PMID:24830448

  17. Wavelet analysis of low-frequency variability in oak tree-ring chronologies from east Central Europe

    NASA Astrophysics Data System (ADS)

    Sen, Asok K.; Kern, Zoltán

    2016-07-01

    This study investigates the low-frequency (interannual and longer period) variability in three hydroclimatic records from east Central Europe. Two of these records consist of climate proxies derived from oak-tree rings in Bakta forest, and Balaton Highlands in Hungary, for the time interval 1783-2003. The third record consists of homogenized instrumental precipitation data from Budapest, Hungary, from 1842 to 2003. Using wavelet analysis, the three time series are analyzed and compared with one another. It is found that all three time series exhibit strong interannual variability at the 2-4 years timescales, and these variations occur intermittently throughout the length of each record. Significant variability is also observed in all the records at decadal timescales, but these variations persist for only two to three cycles. Wavelet coherence among the various time series is used to explore their time-varying correlation. The results reveal significant coherence at the 2-4 years band. At these timescales, the climatic variations are correlated to the tree-ring signal over different time intervals with changing phase. Increased (decreased) contribution of large-scale stratiform precipitation offers a potential explanation for enhanced (faded) coherence at the interannual timescale. Strong coherence was also observed occasionally at decadal timescales, however these coherences did not appear uniformly. These results reinforce the earlier assertion that neither the strength nor the rank of the similarity of the local hydroclimate signals is stable throughout the past two centuries.

  18. Nevada Monitoring System to Assess Climate Variability and Change

    NASA Astrophysics Data System (ADS)

    Devitt, D. A.; Arnone, J.; Biondi, F.; Fenstermaker, L. F.; Saito, L.; Young, M.; Riddle, B.; Strachan, S. D.; Bird, B.; McCurdy, G.; Lyles, B. F.

    2010-12-01

    The Nevada System of Higher Education (University of Nevada Las Vegas, University of Nevada Reno and the Desert Research Institute) was awarded a multiyear NSF EPSCoR grant to support infrastructure associated with regional climate change research. The overall project is comprised of 5 components: education, cyberinfrastructure, policy, climate modeling and water/ecology. The water and ecology components are using their infrastructure funding for the assessment of climate variability and change on ecosystem function and hydrologic services. A series of 10 m tall towers are under construction and are being equipped with a wide array of sensors to monitor atmospheric, soil and plant parameters over time. The towers are located within the Mojave and Great Basin Deserts in two transects; the Mojave Desert transect is located in the southern Nevada Sheep Mountain Range and the Great Basin transect is located in the east central Nevada Snake Mountain Range. The towers are centrally positioned in well-defined vegetation zones. In southern Nevada these zones are represented by the following plant species: Creosote/Bursage (Creosotebush scrub zone); Blackbrush/Joshua Tree (Blackbrush zone); Pinyon/ Juniper (pygmy conifer zone), Ponderosa Pine (montane zone) and Bristlecone Pine (subalpine zone). The Snake Mountain transect incorporates the eastern and western valleys on both sides of the mountain range. The vegetation zones are represented by: Greasewood and mixed shrub (salt desert zone); Big Sage (sagebrush zone); Pinyon/Juniper (pygmy conifer zone); White/Douglas Fir, Ponderosa Pine and Aspen (montane zone); and Bristlecone/Limber Pine and Engelmann Spruce (subalpine zone). We are currently in the third year of funding with a goal of having the majority of towers fully operational by winter 2010. In close collaboration with our cyberinfrastructure component team, all data acquired from the transect monitoring stations will be made available to other researchers and the

  19. Superposed fold-thrust events at the Nevada Test Site

    USGS Publications Warehouse

    Cashman, Patricia H.; Cole, James C.; Trexler, James H., Jr.

    2000-01-01

    The Nevada Test Site (NTS), in southern Nye County, Nevada, straddles significant pre-Tertiary structural and stratigraphic boundaries. Detailed stratigraphy and biostratigraphy of the Upper Paleozoic section delineates the regional trust sheets and constrains their burial histories. The Paleozoic rocks record three phases of contractional deformation, overprinted by strike-slip faulting. These occured in the folloing order: (1) foreland-vergant folding and imbricate thrusting in the footwall of the Belted Range thrust; (2) hinterland-vergent folding and thrusting; and (3) north-vergant folding that we interpret as footwall deformation below a third major thrust system. Sinistral slip, typically accompanied by minor east-west shortening, has occured along a series of north-northeast--north-northwest--striking faults around Yucca Flat. This strike-slip faulting postdates both foreland-vergent and hinterland-vergent deformation, and predates the Cretaceous Climax stock; its age relative to the north-vergent folding and thrusting is unknown. Our new understanding of the geometry of these structures provides new insights into the correlation and interpretation of regional structural features. Field trip stops will examine: (1) the stratigraphic differences that allow us to distinguish the regional thrust sheets and constrain their burial histories; and (2) the field relationships that document the kinematics and relative ages of the penetrative deformational events.

  20. Sequence stratigraphy in a continental extensional basin: A case study from the Goshute Valley, east-central Nevada--Deja vu

    SciTech Connect

    Strecker, U.; Smithson, S.B.; Steidtmann, J.R. . Dept. of Geology and Geophysics)

    1992-01-01

    Previous tectonic interpretations of the Goshute Valley relied upon conventional line drawings of seismic reflectors and suggested an asymmetric basin-fill geometry in response to a listric master fault regime. However, a new interpretation approach using sequence stratigraphic principles not only modifies and adds to earlier structural analyses, but more importantly provides evidence for tectonically induced migratory facies patterns. The application of sequence stratigraphy reveals that the structural basin history is not that of a half-graben experiencing subsidence along a listric master fault. Instead, the basin is bounded by two, essentially planar faults, with greater displacements along the eastern margin fault. In addition, four stages of basin development, including initial sagging, syndepositional faulting, previously unreported tectonic compression, and deactivation can be documented. Tectonism emerges as a very important parameter in controlling the type and distribution of seismic facies, as exemplified by the oblique progradational facies (OPF). Moreover, the slope of a line connecting the inflection points of clinoforms within the OPF may serve to outline the relative importance of aggradation versus progradation within a sequence. This balance represents an independent mechanism to evaluate the rate of basin subsidence and requires further attention. Finally, the overall pattern of progradation present within each sequence suggests that sequences within the Goshute basin do not record a full retrogradational/progradational cycle, as do their marine counterparts.

  1. Geochemical and geophysical analysis of shallow aquifer materials in Pennsylvanian coal-bearing strata in east-central Ohio

    SciTech Connect

    Haefner, R.J.; Rowe, G.L. Jr. . Water Resources Div.)

    1992-01-01

    Three cores holes were drilled through sandstone, shale, and coal deposits of the Pennsylvanian-age Allegheny Group to provide samples for geochemical and geophysical evaluation of shallow aquifer materials in east-central Ohio. The samples were analyzed for forms of sulfur and carbon, and for more than 40 major and trace elements by inductively coupled plasma scans. Temperature, electrical, caliper, and gamma-ray logs were run in the boreholes to improve definition of the stratigraphy and geohydrologic properties of the shallow aquifers. The stratigraphy in this region is dominated by thick sandstone and shale sequences with minor amounts of limestone and the Middle and Lower Kittanning coal/underclay sequences. Depth profiles of major and trace-element chemistry reveal many trace elements are enriched in the underclay with respect to the overlying sandstone/shale sequences. Pyritic-sulfur contents in the underclay is highly variable and in the shale sequences are less than 1 weight percent. Evaluation of the volume-weighted net-neutralization potential of the entire sampling interval indicates an average deficit of approximately 30 tons of CaCO[sub 3] per 1,000 tons of rock in the resultant spoils after mining of the coal. Aquifer properties were inferred from the interpretation of the geophysical logs. Temperature logs reveal that the coals are the major water-bearing units. Minor fractures were seen in the core; these fractures may control vertical ground-water flow within the sampled interval. Gamma logs proved to be the most effective geophysical tool for correlating stratigraphy between the three holes.

  2. Reproductive biology knowledge, and behaviour of teenagers in East, Central and Southern Africa: the Zimbabwe case study.

    PubMed

    Mbizvo, M T; Kasule, J; Gupta, V; Rusakaniko, S; Gumbo, J; Kinoti, S N; Mpanju-Shumbusho, W; Sebina-Zziwa; Mwateba, R; Padayachy, J

    1995-11-01

    Sexuality in the teenager is often complicated by unplanned/unwanted pregnancy, abortion and the risks of STDs including AIDS. There is therefore a need for improved understanding of factors affecting adolescent sexuality and the implementation of programmes designed to improve their knowledge, risk awareness and subsequent behavioural outcomes. A multicentre study of reproductive health knowledge and behaviour followed by a health education intervention was undertaken amongst teenagers in selected countries of East, Central and Southern Africa. Reported here are findings at baseline derived from the Zimbabwe component on reproductive biology knowledge and behavior. A self-administered questionnaire was used among 1 689 adolescent pupils drawn from rural, urban, co-education, single sex, boarding and day secondary schools in Zimbabwe. Correct knowledge on reproductive biology as measured by the meaning and interpretation of menstruation and wet dreams varied by school from 68 pc to 86 pc, with a significant trend (p < 0,01) based on level of education at baseline. The reported mean age at which menarche took place was 13,5 years +/- 1,3 (mean +/- SD). First coitus was reported to have taken place at the mean age of 12 years for boys and 13,6 years for girls. Seventeen pc of the adolescent pupils reported that they were sexually experienced and 33,2 had relationships. There were misconceptions reported on menstruation with 23 pc reporting that it was an illness. Peers, followed by magazines were the first sources of information on various aspects of reproductive biology, both of which might not provide the correct first information. Among pupils reporting that they were sexually experienced, the largest proportion (56 pc) had unprotected sex. The findings point to the need for targeting the adolescent pupils for information on reproductive biology and increased awareness on the risks of pregnancy, STDs and HIV. PMID:8932577

  3. Conodont and fusulinid biostratigraphy and history of the Pennsylvanian to Lower Permian Keeler Basin, east-central California

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.; Ritter, S.M.

    2001-01-01

    The Pennsylvanian-Lower Permian Keeler Canyon Formation and lower part of the Lower Permian Lone Pine Formation in east-central California were deposited in a deep-water basin that originated in the Morrowan (Early Pennsylvanian), was fully established by the Desmoinesian (Middle Pennsylvanian), and lasted into the Sakmarian (Early Permian). Stratigraphic studies indicate that the Keeler Canyon Formation can be divided into members recognizable throughout the area of our detailed mapping. From older to younger they are the Tinemaha Reservoir, Tihvipah Limestone, Cerro Gordo Spring, and Salt Tram Members. Rocks in this basin, here referred to as the Keeler basin, contain numerous fusulinid and conodont faunas most of which were deposited by sediment-gravity flows probably originating at the margin of the Bird Spring carbonate platform to the northeast. Sixty-one species of Atokan to Sakmarian fusulinids and 38 species of Desmoinesian to Sakmarian conodonts are recognized. These, in addition to four species of Morrowan conodonts previously reported, show that every stage from the Morrowan to Sakmarian is represented in the basin. The fusulinid faunas are composed largely of taxa of the North American craton, especially the south-central USA, with important endemic constituents and some McCloud Limestone forms, representing the Eastern Klamath terrane. Conodonts are closely similar to species in the Ural Mountains region of Russia and Kazakhstan, as well as the American midcontinent. The co-occurrence of fusulinids and conodonts in the Keeler basin results in a better correlation of zones based on these two groups of fossils than generally is possible.

  4. Significance of tourmaline-rich rocks in the north range group of the cuyuna iron range, East-Central Minnesota

    USGS Publications Warehouse

    Cleland, J.M.; Morey, G.B.; McSwiggen, P.L.

    1996-01-01

    Concentrations of tourmaline in Early Proterozoic metasedirnentary rocks of the Cuyuna iron range, east-central Minnesota, provide a basis for redefinition of the evolutionary history of the area. Manganiferous iron ore forms beds within the Early Proterozoic Trommald Formation, between thick-bedded granular iron-formation having shallow-water depositional attributes and thin-bedded, nongranular iron-formation having deeper water attributes. These manganese-rich units were previously assumed to be sedimentary in origin. However, a revaluation of drill core and mine samples from the Cuyuna North range has identified strata-bound tourmaline and tourmalinite, which has led to a rethinking of genetic models for the geology of the North range. We interpret the tourmaline-rich rocks of the area to be a product of submarine-hydrothermal solutions flowing along and beneath the sedirnent-seawater interface. This model for the depositional environment of the tourmaline is supported by previously reported mineral assemblages within the Trommald Formation that comprise aegirine; barium feldspar; manganese silicates, carbonates, and oxides; and Sr-rich barite veins. In many places, tourmaline-rich metasedimentary rocks and tourmalinites are associated locally with strata-bound sulfide deposits. At those localities, the tourmaline-rich strata are thought to be lateral equivalents of exhalative sulfide zones or genetically related subsea-floor replacements. On the basis of the occurrence of the tourmaline-rich rocks and tourmalinites, and on the associated minerals, we suggest that there is a previously unrecognized potential for sediment-hosted sulfide deposits in the Cuyuna North range.

  5. Neurovirulence comparison of chikungunya virus isolates of the Asian and East/Central/South African genotypes from Malaysia.

    PubMed

    Chiam, Chun Wei; Chan, Yoke Fun; Ong, Kien Chai; Wong, Kum Thong; Sam, I-Ching

    2015-11-01

    Chikungunya virus (CHIKV), an alphavirus of the family Togaviridae, causes fever, polyarthritis and rash. There are three genotypes: West African, Asian and East/Central/South African (ECSA). The latter two genotypes have caused global outbreaks in recent years. Recent ECSA CHIKV outbreaks have been associated with severe neurological disease, but it is not known if different CHIKV genotypes are associated with different neurovirulence. In this study, the neurovirulence of Asian (MY/06/37348) and ECSA (MY/08/065) strains of CHIKV isolated in Malaysia were compared. Intracerebral inoculation of either virus into suckling mice was followed by virus titration, histopathology and gene expression analysis of the harvested brains. Both strains of CHIKV replicated similarly, yet mice infected with MY/06/37348 showed higher mortality. Histopathology findings showed that both CHIKV strains spread within the brain (where CHIKV antigen was localized to astrocytes and neurons) and beyond to skeletal muscle. In MY/06/37348-infected mice, apoptosis, which is associated with neurovirulence in alphaviruses, was observed earlier in brains. Comparison of gene expression showed that a pro-apoptotic gene (eIF2αK2) was upregulated at higher levels in MY/06/37348-infected mice, while genes involved in anti-apoptosis (BIRC3), antiviral responses and central nervous system protection (including CD40, IL-10RA, MyD88 and PYCARD) were upregulated more highly in MY/08/065-infected mice. In conclusion, the higher mortality observed following MY/06/37348 infection in mice is due not to higher viral replication in the brain, but to differentially expressed genes involved in host immune responses. These findings may help to identify therapeutic strategies and biomarkers for neurological CHIKV infections. PMID:26276497

  6. Temporal trends of pollution Pb and other metals in east-central Baffin Island inferred from lake sediment geochemistry.

    PubMed

    Michelutti, Neal; Simonetti, Antonio; Briner, Jason P; Funder, Svend; Creaser, Robert A; Wolfe, Alexander P

    2009-10-15

    Concentrations and stable isotope ratios of lead (Pb) from lake sediments were used to quantify temporal patterns of anthropogenic Pb pollution in the Clyde River region of Baffin Island, Arctic Canada. Surface sediments from eight lakes on eastern Baffin Island and one from northern-most Greenland, spanning a gradient of 20 degrees latitude, showed great variability with respect to Pb concentration and stable isotopic Pb ratios, with little apparent latitudinal trend. To constrain the temporal evolution of regional Pb pollution, a well-dated core from one of the sites, Lake CF8 on east-central Baffin Island, was analyzed geochemically at high stratigraphic resolution. A pronounced decrease in the (206)Pb/(207)Pb ratio occurs in sediments deposited between 1923 and the mid-1970s, likely reflecting alkyl-Pb additives derived from the combustion of fossil fuels at a global scale. A two-component mixing model indicates that 17-26% of the Pb in the labile fraction of sediments deposited in Lake CF8 between 2001 and 2005 is from anthropogenic input. A Pb-Pb co-isotopic plot ((206)Pb/(207)Pb vs.(208)Pb/(206)Pb ratios) of the Lake CF8 time series data indicates multiple possible sources of industrial Pb pollution. Despite widespread reductions in industrial Pb emissions since the 1970s, there is no evidence for attendant reductions of pollution Pb at Lake CF8. Enhanced scavenging from increased primary production as well as changing precipitation rates as climate warms may represent important factors that modulate Pb deposition to Lake CF8, and Arctic lakes elsewhere. PMID:19665172

  7. Petrology, geochemistry and isotope data on a ultrahigh-pressure jadeite quartzite from Shuanghe, Dabie Mountains, East-central China

    NASA Astrophysics Data System (ADS)

    Liou, J. G.; Zhang, R. Y.; Jahn, Bor-ming

    1997-08-01

    In the Dabie ultrahigh-pressure terrane of east-central China, coesite-bearing jadeite quartzites occur locally as intercalated layers with marble and mafic eclogite. This rock assemblage is, in turn, enclosed within quartzofeldspathic gneisses. Metamorphic parageneses and kelyphitic textures reveal a multistage metamorphic evolution and complex exhumation history. The primary peak metamorphic assemblage consists of jadeite + garnet + coesite + rutile ± apatite. Minor coesite and coesite pseudomorphs occur as inclusions in jadeite and garnet. Three stages of retrograde assemblages are observed in the jadeite quartzites. Stage A is represented by the polymorphic transformation of coesite to quartz aggregates. Stage B is characterized by formation of coronas around jadeite porphyroblasts consisting of an inner layer of oligoclase + amphibole and an outer layer of albite ± aegirine—augite. The last stage (stage C) involved total replacement of jadeite and most garnets by taramitic amphibole + albite + aegirine-augite. Peak metamorphic P-T conditions were > 26 kbar at 660°C and are consistent with the estimates from the adjacent coesite-bearing eclogites. The jadeite quartzites display clockwise P-T path that matches those of the adjacent eclogites. Major and trace element data suggest that the protolith of the jadeite quartzite could have been an albitized siltstone enriched in Na and depleted in K and Ca. The highly negative present-day ɛNd value (-24.7) indicates a very old age for the protolith. Its late Archean model age (TDM) of 2.58 Ga is among the oldest so far identified for rocks from the Dabie UHPM terrane. Concordant field relations and petrogenetic considerations suggest that all mafic, politic, carbonate and gneissic rocks have experienced in-situ UHP metamorphism during Triassic continental collision between the Sino-Korean and Yangtze cratons.

  8. Geologic Map and Engineering Properties of the Surficial Deposits of the Tok Area, East-Central Alaska

    USGS Publications Warehouse

    Carrara, Paul E.

    2007-01-01

    The Tok area 1:100,000-scale map, through which the Alaska Highway runs, is in east-central Alaska about 160 km west of the Yukon border. The surficial geologic mapping in the map area is in support of the 'Geologic Mapping in support of land, resources, and hazards issues in Alaska' Project of the USGS National Cooperative Geologic Mapping Program. The Tok map area contains parts of three physiographic provinces, the Alaska Range, the Yukon-Tanana Upland, and the Northway-Tanana Lowland. The high, rugged, glaciated landscape of the eastern Alaska Range dominates the southwestern map area. The highest peak, an unnamed summit at the head of Cathedral Rapids Creek No. 2, rises to 2166 m. The gently rolling hills of the Yukon-Tanana Upland, in the northern map area, rise to about 1000 m. The Northway-Tanana Lowland contains the valley of the westerly flowing Tanana River. Elevations along the floor of the lowland generally range between 470 and 520 m. The dominant feature within the map is the Tok fan, which occupies about 20 percent of the map area. This large (450 km2), nearly featureless fan contains a high percentage of volcanic clasts derived from outside the present-day drainage of the Tok River. Because the map area is dominated by various surficial deposits, the map depicts 26 different surficial units consisting of man-made, alluvial, colluvial, eolian, lacustrine, organic, glaciofluvial, glacial, and periglacial deposits. The accompanying table provides information concerning the various units including their properties, characteristics, resource potential, and associated hazards in this area of the upper Tanana valley.

  9. Detrital zircon geochronology of the Adams Argillite and Nation River Formation, east-central Alaska, U.S.A

    USGS Publications Warehouse

    Gehrels, G.E.; Johnsson, M.J.; Howell, D.G.

    1999-01-01

    The Cambrian Adams Argillite and the Devonian Nation River Formation are two sandstone-bearing units within a remarkably complete Paleozoic stratigraphic section in east-central Alaska. These strata, now foreshortened and fault-bounded, were originally contiguous with miogeoclinal strata to the east that formed as a passive-margin sequence along the northwestern margin of the North American continent. Seventy-five detrital zircon grains from the Adams Argillite and the Nation River Formation were analyzed in an effort to provide constraints on the original sources of the grains, and to generate a detrital zircon reference for miogeoclinal strata in the northern Cordillera. Thirty-five single zircon grains from a quartzite in the Adams Argillite yield dominant age clusters of 1047-1094 (n = 6), 1801-1868 (n = 10), and 2564-2687 (n = 5) Ma. Forty zircons extracted from a sandstone in the Nation River Formation yield clusters primarily of 424-434 (n = 6), 1815-1838 (n = 6), 1874-1921 (n = 7), and 2653-2771 (n = 4) Ma. The Early Proterozoic and Archean grains in both units probably originated in basement rocks in a broad region of the Canadian Shield. In contrast, the original igneous sources for mid-Protcrozoic grains in the Adams Argillite and ??? 430 Ma grains in the Nation River Formation are more difficult to identify. Possible original sources for the mid-Proterozoic grains include: (1) the Grenville Province of eastern Laurentia, (2) the Pearya terrane along the Arctic margin, and (3) mid-Proterozoic igneous rocks that may have been widespread along or outboard of the Cordilleran margin. The ??? 430 Ma grains may have originated in: (1) arc-type sources along the Cordilleran margin, (2) the Caledonian orogen, or (3) a landmass, such as Pearya, Siberia, or crustal fragments now in northern Asia, that resided outboard of the Innuitian orogen during mid-Paleozoic time. Copyright ?? 1999, SEPM (Society for Sedimentary Geology).

  10. Geologic map of Paleozoic rocks in the Calico Hills, Nevada Test Site, southern Nevada

    SciTech Connect

    Cole, J.C.; Cashman, P.H.

    1998-11-01

    The Calico Hills area in the southwestern part of the Nevada Test Site, Nye County, Nevada, exposes a core of pre-Tertiary rocks surrounded by middle Miocene volcanic strata. This map portrays the very complex relationships among the pre-Tertiary stratigraphic units of the region. The Devonian and Mississippian rocks of the Calico Hills are distinct from age-equivalent carbonate-shelf or submarine-fan strata in other parts of the Nevada Test Site. The Calico Hills strata are interpreted to have been deposited beyond the continental shelf edge from alternating silicic and carbonate clastic sources. Structures of the Calico Hills area record the compounded effects of: (1) eastward-directed, foreland-vergent thrusting; (2) younger folds, kink zones, and thrusts formed by hinterland-vergent deformation toward northwesterly and northerly directions; and (3) low-angle normal faults that displaced blocks of Middle Paleozoic carbonate strata across the contractionally deformed terrane. All of these structures are older than any of the middle Miocene volcanic rocks that were erupted across the Calico Hills.

  11. [Public food service in Milan city and Hinterland: food-handlers training level (Part 2)].

    PubMed

    Pontello, M; Dal Vecchio, A; Doria, M G; Bertini, I

    2005-01-01

    The prevention and control of foodborne diseases play an important role in public health and the responsibility of food-handlers is of great concern: their training on food safety is particularly required in the critical sector of public food service establishments. The food-handlers knowledge has been evaluated by a questionnaire filled up in two Public Health Units (PHU) in Milan City and Milan hinterland. Only 11.5% of food-handlers turned at to be good trained; the wrong answers are concentrated on the section titled "temperatures management" (68 and 59% in Milan City and in Milan hinterland, respectively). Only for 31.4% of food-handlers the attendance to training courses is well documented, although the knowledge level seems to be partially influenced by training activity: exclusively in Milan City food-handlers an highly significant difference has been found among "trained" and "no-trained" workers in correct answers about temperatures management (p= 0.0046). The frequency of exact answers isn't associated to the satisfaction level revealed during inspection of restaurants. Focusing the attention on the insufficient efficacy of training courses and the lacking connection between knowledge and behaviour, a critical revision of training activity quality seems to be necessary. In future some professional training activities in the field should be promoted. PMID:16041927

  12. [Public food service in Milan city and Hinterland: GMP application (Part 1)].

    PubMed

    Pontello, M; Dal Vecchio, A; Bertini, I; Valerio, E

    2005-01-01

    Food service establishments are recognized as a critical sector concerning foodborne diseases occurrence, that is associated to contributing factors such as the anticipated preparation of meals that are often highly handled, and long-time distributed. A survey has been planned to evaluate the application of HACCP plan, in order to select a statistically representative sample of food services (restaurant, pizza-shop, bar, ..) in two Milan area' Public Health Units (PHU). During the inspections a proper check-list has been filled up in order to give a conformity evaluation about the global situation and about three specific sections: hygiene of food-handlers, procedures control, temperatures management. The food services have been found satisfactory in 9/106 and 5/54 cases in Milan City and in hinterland, respectively; among the two areas, highly significant differences have been revealed about temperatures management (68% and 28% unsatisfactory, respectively). In Milan City restaurants provided with HACCP plan scores are significantly different from unprovided restaurants scores (global and the three sections' evaluation); in Milan hinterland differences between provided and unprovided HACCP plan restaurants regard temperature management scores only. Useful suggestions to improve the quality of surveillance activity come from complex and heterogeneous findings shown in this study. PMID:16041926

  13. Antigenic Variation of East/Central/South African and Asian Chikungunya Virus Genotypes in Neutralization by Immune Sera

    PubMed Central

    Chua, Chong-Long; Sam, I-Ching; Merits, Andres; Chan, Yoke-Fun

    2016-01-01

    Background Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus which causes epidemics of fever, severe joint pain and rash. Between 2005 and 2010, the East/Central/South African (ECSA) genotype was responsible for global explosive outbreaks across India, the Indian Ocean and Southeast Asia. From late 2013, Asian genotype CHIKV has caused outbreaks in the Americas. The characteristics of cross-antibody efficacy and epitopes are poorly understood. Methodology/Principal Findings We characterized human immune sera collected during two independent outbreaks in Malaysia of the Asian genotype in 2006 and the ECSA genotype in 2008–2010. Neutralizing capacity was analyzed against representative clinical isolates as well as viruses rescued from infectious clones of ECSA and Asian CHIKV. Using whole virus antigen and recombinant E1 and E2 envelope glycoproteins, we further investigated antibody binding sites, epitopes, and antibody titers. Both ECSA and Asian sera demonstrated stronger neutralizing capacity against the ECSA genotype, which corresponded to strong epitope-antibody interaction. ECSA serum targeted conformational epitope sites in the E1-E2 glycoprotein, and E1-E211K, E2-I2T, E2-H5N, E2-G118S and E2-S194G are key amino acids that enhance cross-neutralizing efficacy. As for Asian serum, the antibodies targeting E2 glycoprotein correlated with neutralizing efficacy, and I2T, H5N, G118S and S194G altered and improved the neutralization profile. Rabbit polyclonal antibody against the N-terminal linear neutralizing epitope from the ECSA sequence has reduced binding capacity and neutralization efficacy against Asian CHIKV. These findings imply that the choice of vaccine strain may impact cross-protection against different genotypes. Conclusion/Significance Immune serum from humans infected with CHIKV of either ECSA or Asian genotypes showed differences in binding and neutralization characteristics. These findings have implications for the continued

  14. Digital data sets that describe aquifer characteristics of the Vamoosa-Ada aquifer in east-central Oklahoma

    USGS Publications Warehouse

    Abbott, Marvin M.; Runkle, D.L.; Rea, Alan

    1997-01-01

    Nonproprietary format files This diskette contains digitized aquifer boundaries and maps of hydraulic conductivity, recharge, and ground-water level elevation contours for the Vamoosa-Ada aquifer in east-central Oklahoma. The Vamoosa-Ada aquifer is an important source of water that underlies about 2,320-square miles of parts of Osage, Pawnee, Payne, Creek, Lincoln, Okfuskee, and Seminole Counties. Approximately 75 percent of the water withdrawn from the Vamoosa-Ada aquifer is for municipal use. Rural domestic use and water for stock animals account for most of the remaining water withdrawn. The Vamoosa-Ada aquifer is defined in a ground-water report as consisting principally of the rocks of the Late Pennsylvanian-age Vamoosa Formation and overlying Ada Group. The Vamoosa-Ada aquifer consists of a complex sequence of fine- to very fine-grained sandstone, siltstone, shale, and conglomerate interbedded with very thin limestones. The water-yielding capabilities of the aquifer are generally controlled by lateral and vertical distribution of the sandstone beds and their physical characteristics. The Vamoosa-Ada aquifer is unconfined where it outcrops in about an 1,700-square-mile area. Most of the lines in the aquifer boundary, hydraulic conductivity, and recharge data sets were extracted from published digital surficial geology data sets based on a scale of 1:250,000, and represent geologic contacts. Some of lines in the data sets were interpolated in areas where the Vamoosa-Ada aquifer is overlain by alluvial and terrace deposits near streams and rivers. These data sets include only the outcrop area of the Vamoosa-Ada aquifer and where the aquifer is overlain by alluvial and terrace deposits. The hydraulic conductivity value and recharge rate are from a ground-water report about the Vamoosa-Ada aquifer. The water-level elevation contours were digitized from a mylar map, at a scale of 1:250,000, used to publish a plate in a ground-water report about the Vamoosa

  15. Hydrochemistry of the Mahomet Bedrock Valley Aquifer, East-Central Illinois: indicators of recharge and ground-water flow

    USGS Publications Warehouse

    Panno, S.V.; Hackley, Keith C.; Cartwright, K.; Liu, Chao-Li

    1994-01-01

    A conceptual model of the ground-water flow and recharge to the Mahomet Bedrock Valley Aquifer (MVA), east-central Illinois, was developed using major ion chemistry and isotope geochemistry. The MVA is a 'basal' fill in the east-west trending buried bedrock valley composed of clean, permeable sand and gravel to thicknesses of up to 61 m. It is covered by a thick sequence of glacial till containing thinner bodies of interbedded sand and gravel. Ground water from the MVA was found to be characterized by clearly defined geochemical regions with three distinct ground-water types. A fourth ground-water type was found at the confluence of the MVA and the Mackinaw Bedrock Valley Aquifer (MAK) to the west. Ground water in the Onarga Valley, a northeastern tributary of the MVA, is of two types, a mixed cation-SO42- type and a mixed cation-HCO3- type. The ground water is enriched in Na+, Ca2+, Mg2+, and SO42- which appears to be the result of an upward hydraulic gradient and interaction of deeper ground water with oxidized pyritic coals and shale. We suggest that recharge to the Onarga Valley and overlying aquifers is 100% from bedrock (leakage) and lateral flow from the MVA to the south. The central MVA (south of the Onarga Valley) is composed of relatively dilute ground water of a mixed cation-HCO3- type, with low total dissolved solids, and very low concentrations of Cl- and SO42-. Stratigraphic relationships of overlying aquifers and ground-water chemistry of these and the MVA suggest recharge to this region of the MVA (predominantly in Champaign County) is relatively rapid and primarily from the surface. Midway along the westerly flow path of the MVA (western MVA), ground water is a mixed cation-HCO3- type with relatively high Cl-, where Cl- increases abruptly by one to ??? two orders of magnitude. Data suggest that the increase in Cl- is the result of leakage of saline ground water from bedrock into the MVA. Mass-balance calculations indicate that approximately 9.5% of

  16. Petrography, diagenesis and reservoir characteristics of the Pre-Cenomanian sandstone, Sheikh Attia area, East Central Sinai, Egypt

    NASA Astrophysics Data System (ADS)

    Kassab, Mohamed A.; Hassanain, Ibrahim M.; Salem, Alaa M.

    2014-08-01

    The diagenetic influence on reservoir characteristics was investigated for the Pre-Cenomanian (Early Paleozoic and Early Cretaceous) sandstone sequence in the Sheikh Attia area, East Central Sinai. This sequence can be distinguished into four formations: Sarabit El-Khadim Formation (Cambrian) at the base, Abu Hamata Formation (Cambro-Ordovician), Adedia Formation (Ordovician-Silurian) and Malha Formation (Early Cretaceous) on the top. The sandstones of Pre-Cenomanian sequence in the Sheikh Attia area are dominantly quartz arenites and subarkoses, where the quartz grains constitute about 82.3-98.4% of the framework composition with an average value of approximately 94% of the framework composition. Feldspars range in abundance from 0% to14.2%, with an average value of about 3% of the framework composition. The rock fragments constitute up to 9.8% of volume percent of framework grains, with an average of about 2.7%. Diagenetic events identified in these sandstones include compaction, cementation by calcite, quartz, clay minerals and iron oxides, dissolution and alteration of unstable clastic grains, and tectonically induced grain fracturing. Unstable clastic grains like feldspars suffered considerable alteration to kaolinite. The Pre-Cenomanian (Early Paleozoic and Early Cretaceous) sandstones possess good reservoir characteristics because they retain sufficient porosity and permeability in some intervals. These sandstones are characterized by porosity ranges between 3.80% and 27.60%, and have a permeability range from k ⩽ 0.03 mD, for tight sandstones to k ⩾ 50 mD, for the more permeable parts. The Pre-Cenomanian sandstones can be classified into four petrophysical flow units (megaport, macroport, mesoport and microport) with varying reservoir performances and are distinguished by comparable ranges of R35. Petrographic observations showed that the Early Paleozoic sandstones are texturally immature owing to the abundance of angular grains, non-uniformity of grain

  17. Lone Tree prospect area, Railroad Valley, Nevada

    SciTech Connect

    Montgomery, S.L.

    1997-02-01

    Continued exploration in the Basin and Range of Nevada has resulted in a number of small field discoveries that confirm widespread oil generation and suggest potential in local prospect settings. One such setting, the Lone Tree prospect area, lies approximately 6.5 mi (10.4 km) southwest of Grant Canyon field in Railroad Valley. Discovered in 1983, this field had produced nearly 20 million bbl of oil by June 1996, mostly from two wells. Oil is entrapped in a slide block of fractured Paleozoic strata juxtaposed against Mississippian source rocks along a detachment fault of probable early Tertiary age. Subsequent exploration has focused on attempts to identify such blocks elsewhere in east-central Nevada, particularly in Railroad and Pine Valleys. Well, gravity, and two-dimensional seismic data suggested the existence of such a block in the Lone Tree area. These data were used as a basis for a three-dimensional seismic survey. Information from this survey identified a prospect at the structural culmination of the interpreted block. The resulting well, the 13-14 Timber Mountain, was commercially unsuccessful but yielded important new data, suggesting a need to revise existing stratigraphy and structural history. In addition, a second prospect, located farther updip, was indicated.

  18. Captures of western corn rootworm (Coleoptera: Chrysomelidae) adults with Pherocon AM and vial traps in four crops in east central Illinois.

    PubMed

    Rondon, Silvia I; Gray, Michael E

    2003-06-01

    It is hypothesized that the long-term rotation of maize (Zea mays L.) and soybean (Glycine max L.) in east central Illinois has caused a significant change in the ovipositional behavior of the western corn rootworm, Diabrotica virgifera virgifera LeConte. Since the mid 1990s in east central Illinois, western corn rootworm adults have been observed feeding on soybean foliage and also now use soybean fields as egg laying sites. This behavioral adaptation has greatly decreased the effectiveness of rotation as a pest management tactic. By using Pherocon AM and vial traps, we evaluated the influence of maize, soybean, oat stubble (Avena sativa L.), and alfalfa (Medicago sativa L.) on male and female adult western corn rootworm densities from April 1998 through September 2000 near Urbana, IL. Our results indicated that western corn rootworm adults are common inhabitants of maize, soybean, oat stubble, and alfalfa. Trapping efforts with both Pherocon AM (attractive) and vial traps (passive) revealed that initial densities of both male and female western corn rootworm adults were greater in maize. Soon after emergence, densities of females began to decline within maize and increase in other crops (soybean, oat stubble, and alfalfa). Results from this experiment support the hypothesis that variant western corn rootworm females in east central Illinois are colonizing crops other than maize at densities of potential economic importance. Those producers who choose to rotate maize with soybean or alfalfa may remain at risk to economic larval injury to maize roots. Potentially, oat stubble also may support levels of western corn rootworm females resulting in sufficient oviposition to cause economic losses to rotated maize the following season. PMID:12852611

  19. Fault-controlled CO2 leakage from natural reservoirs in the Colorado Plateau, East-Central Utah

    NASA Astrophysics Data System (ADS)

    Jung, Na-Hyun; Han, Weon Shik; Watson, Z. T.; Graham, Jack P.; Kim, Kue-Young

    2014-10-01

    The study investigated a natural analogue for soil CO2 fluxes where CO2 has naturally leaked on the Colorado Plateau, East-Central Utah in order to identify various factors that control CO2 leakage and to understand regional-scale CO2 leakage processes in fault systems. The total 332 and 140 measurements of soil CO2 flux were made at 287 and 129 sites in the Little Grand Wash (LGW) and Salt Wash (SW) fault zones, respectively. Measurement sites for CO2 flux involved not only conspicuous CO2 degassing features (e.g., CO2-driven springs/geysers) but also linear features (e.g., joints/fractures and areas of diffusive leakage around a fault damage zone). CO2 flux anomalies were mostly observed along the fault traces. Specifically, CO2 flux anomalies were focused in the northern footwall of the both LGW and SW faults, supporting the existence of north-plunging anticlinal CO2 trap against south-dipping faults as well as higher probability of the north major fault traces as conduits. Anomalous CO2 fluxes also appeared in active travertines adjacent to CO2-driven cold springs and geysers (e.g., 36,259 g m-2 d-1 at Crystal Geyser), ancient travertines (e.g., 5,917 g m-2 d-1), joint zones in sandstone (e.g., 120 g m-2 d-1), and brine discharge zones (e.g., 5,515 g m-2 d-1). These observations indicate that CO2 has escaped through those pathways and that CO2 leakage from these fault zones does not correspond to point source leakage. The magnitude of CO2 flux is progressively reduced from north (i.e. the LGW fault zone, ∼36,259 g m-2 d-1) to south (i.e. the SW fault zone, ∼1,428 g m-2 d-1) despite new inputs of CO2 and CO2-saturated brine to the northerly SW fault from depth. This discrepancy in CO2 flux is most likely resulting from the differences in fault zone architecture and associated permeability structure. CO2-rich fluids from the LGW fault zone may become depleted with respect to CO2 during lateral transport, resulting in an additional decrease in CO2 fluxes

  20. Relations between groundwater levels and anthropogenic and meteorological stressors at selected sites in east-central Florida, 1995-2007

    USGS Publications Warehouse

    Murray, Louis C., Jr.

    2010-01-01

    Multivariate linear regression analyses were used to define the relations of water levels in the Upper Floridan aquifer (UFA) and surficial aquifer system (SAS) to anthropogenic and meteorological stressors between 1995 and 2007 at two monitoring well sites (Charlotte Street and Lake Oliver) in east-central Florida. Anthropogenic stressors of interest included municipal and agricultural groundwater withdrawals, and application of reclaimed-water to rapid-infiltration basins (source of aquifer recharge). Meteorological stressors included precipitation and potential evapotranspiration. Overall, anthropogenic and meteorological stressors accounted for about 40 to 89 percent of the variance in UFA and SAS groundwater levels and water-level changes. While mean monthly water levels were better correlated with monthly stressor values, changes in UFA and SAS water levels were better correlated with changes in stressor values. Water levels and water-level changes were influenced by system persistence as the moving-averaged values of both stressor types, which accounted for the influence of the previous month(s) conditions, consistently yielded higher adjusted coefficients of determination (R2 adj) values than did single monthly values. While monthly water-level changes tend to be influenced equally with both stressors across the hydrologically averaged 13-year period, changes were more influenced by one stressor or the other seasonally and during extended wet and dry periods. Seasonally, UFA water-level changes tended to be more influenced by anthropogenic stressors than by meteorological stressors, while changes in SAS water levels tended to be more influenced by meteorological stressors. During extended dry periods (12 months or greater), changes in UFA water levels at Charlotte Street were more affected by anthropogenic stressors than by meteorological stressors, while changes in SAS levels were more affected by meteorological stressors. At Lake Oliver, changes in both

  1. Using Flow Regime Lightning and Sounding Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred; Short, David; Wolkmer, Matthew; Sharp, David; Spratt, Scott

    2006-01-01

    Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (http://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Currently, the forecasters create each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent is to improve consistency between forecasters while allowing them to focus on the

  2. Using Flow Regime Lightning and Sounding Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred; Short, David; Volkmer, Matthew; Sharp, David; Spratt, Scott

    2007-01-01

    Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (httl://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Until recently, the forecasters created each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent was to improve consistency between forecasters while allowing them to focus on the

  3. Sedimentation, sediment quality, and upstream channel stability, John Redmond Reservoir, east-central Kansas, 1964-2009

    USGS Publications Warehouse

    Juracek, Kyle E.

    2010-01-01

    A combination of available bathymetric-survey information, bottom-sediment coring, and historical streamgage information was used to investigate sedimentation, sediment quality, and upstream channel stability for John Redmond Reservoir, east-central Kansas. Ongoing sedimentation is reducing the ability of the reservoir to serve several purposes including flood control, water supply, and recreation. The total estimated volume and mass of bottom sediment deposited between 1964 and 2009 in the conservation pool of the reservoir was 1.46 billion cubic feet and 55.8 billion pounds, respectively. The estimated sediment volume occupied about 41 percent of the conservation-pool, water-storage capacity of the reservoir. Water-storage capacity in the conservation pool has been lost to sedimentation at a rate of about 1 percent annually. Mean annual net sediment deposition since 1964 in the conservation pool of the reservoir was estimated to be 1.24 billion pounds per year. Mean annual net sediment yield from the reservoir basin was estimated to be 411,000 pounds per square mile per year Information from sediment cores shows that throughout the history of John Redmond Reservoir, total nitrogen concentrations in the deposited sediment generally were uniform indicating consistent nitrogen inputs to the reservoir. Total phosphorus concentrations in the deposited sediment were more variable than total nitrogen indicating the possibility of changing phosphorus inputs to the reservoir. As the principal limiting factor for primary production in most freshwater environments, phosphorus is of particular importance because increased inputs can contribute to accelerated reservoir eutrophication and the production of algal toxins and taste-and-odor compounds. The mean annual net loads of total nitrogen and total phosphorus deposited in the bottom sediment of the reservoir were estimated to be 2,350,000 pounds per year and 1,030,000 pounds per year, respectively. The estimated mean annual

  4. Anatexis and metamorphism in tectonically thickened continental crust exemplified by the Sevier hinterland, western North America

    NASA Technical Reports Server (NTRS)

    Patino Douce, Alberto E.; Humphreys, Eugene D.; Johnston, A. Dana

    1990-01-01

    This paper presents a thermal and petrologic model of anatexis and metamorphism in regions of crustal thickening exemplified by the Sevier hinterland in western North America, and uses the model to examine the geological and physical processes leading to crustally derived magmatism. The results of numerical experiments show that anatexis was an inevitable end-product of Barrovian metamorphism in the thickened crust of the late Mesozoic Sevier orogenic belt and that the advection of heat across the lithosphere, in the form of mantle-derived mafic magmas, was not required for melting of metasedimentary rocks. It is suggested that, in the Sevier belt, as in other intracontinental orogenic belts, anatexis occurred in the midcrust and not at the base of the crust.

  5. Possible late middle Ordovician organic carbon isotope excursion: evidence from Ordovician oils and hydrocarbon source rocks, Mid-Continent and east-central United States

    SciTech Connect

    Hatch, J.R.; Jacobson, S.R.; Witzke, B.J.; Risatti, J.B.; Anders, D.E.; Watney, W.L.; Newell, K.D.; Vuletich, A.K.

    1987-11-01

    A possible coeval excursion in organic-matter delta/sup 13/C is recognized in different late Middle Ordovician lithologic facies over a distance of 480 mi (770 km), perhaps 930 mi (1500 km), in the Mid-Continent and east-central US. The large variability in the carbon isotope compositions of Ordovician oils from the Mid-Continent and east-central US is a direct result of the variable carbon isotope composition of organic matter in the Middle Ordovician hydrocarbon source rocks. The excursion in organic-matter delta/sup 13/C in late Middle Ordovician rocks may reflect significantly increased organic matter productivity and/or preservation. The excursion is not directly related to maceral composition of the organic matter. Limited dissolved CO/sub 2/ availability, possibly a result of continued high organic matter productivity, and limited circulation in the Middle Ordovician seas may have increased the size of the excursion in organic matter delta/sup 13/C. 5 figures, 4 tables.

  6. Monte Mountain thrust, additional confirmation of the central Nevada thrust

    SciTech Connect

    Chamberlain, A.K. ); Chamberlain, R.L. )

    1990-05-01

    The Monte Mountain thrust, a newly identified thrust exposed in the Timpahute Range, east central Nevada places porous Devonian reservoir rocks over rich Mississippian source rocks at the peak oil generating window. The thrust provides insurmountable evidence of a thrust model that may lead to discovery of giant oil and gas fields along the 400-mi long central Nevada thrust belt. The Timpahute Range lies a little over 50 mi on strike to the south of the prolific Grant Canyon field. Scattered remnants of the north-trending thrust belt are obscured by parallel valleys of Tertiary valley fill and volcanics. The fact that the east-west-trending Timpahute Range could contain exposures of the north-south-trending central Nevada thrust belt attracted them to the range, Familiarity with the stratigraphic section led to the discovery of the thrust. As much as 750 ft of Devonian Guilmette sandstones, in the hanging wall just above the thrust contact have been erroneously mapped as Mississippian Scotty Wash sandstones. These Devonian sandstones could be excellent reservoir rocks. Sandstones in the Guilmette increase in thickness westward. East-vergent thrusting has juxtaposed plates of thicker Guilmette sandstones with plates of thinner sandstones, Reconstruction of Devonian paleogeography provides a clue to the amount of displacement along thrust boundaries.

  7. Dust flux estimates for the Last Glacial Period in East Central Europe based on terrestrial records of loess deposits: a review

    NASA Astrophysics Data System (ADS)

    Újvári, Gábor; Kovács, János; Varga, György; Raucsik, Béla; Marković, Slobodan B.

    2010-11-01

    Loess-paleosol sequences are significant records of the mineral dust cycle of glacial-interglacial periods. As dust particles give rise to direct and indirect radiative forcing, obtaining a reliable picture of the global and regional patterns of mineral dust fluxes during glacial periods can lead to a better understanding of the contribution of mineral dust to past climate changes. Recent progress in absolute dating of loess deposits in the Carpathian Basin in East Central Europe made it possible to provide correct aeolian flux estimates for the Last Glacial period, marine isotope stage (MIS) 2. Mass accumulation rates (MARs) from chronological data of 33 loess sites exhibited a wide range of values, from 150 to 1422 g m -2 a -1, centered around median and mean values of 338 and 417 g m -2 a -1. MAR and MAR estimates have been also calculated using grain size measurements of many loess samples and loess MARs in order to facilitate comparison with models, and since particles larger than 10 μm have a negligible radiative effect. Here we show that some previous model simulations of the dust cycle at the Last Glacial Maximum (LGM) significantly underestimated the real aeolian flux (ranges of our estimates: MAR=34-324 and MAR=9.3-88.2 g m a) in East Central Europe. For this reason, some simulations of dust-induced direct radiative forcing of the LGM climate failed to yield reliable results for this mid-latitude region as they have been based on three-dimensional dust field models that are not capable of estimating the real aeolian fluxes in Central Europe. A recent global model of top of the atmosphere (TOA) radiative forcing by mineral aerosols at the LGM that has been based on more realistic parameterization of dust sources, transport, and deposition revealed zonally averaged surface cooling of -2 °C for the latitudes of our study area. This surface cooling and TOA radiative forcing (-2 to -3 W m -2) are greater than recognized in other models and draws our

  8. The Lower Triassic Sorkh Shale Formation of the Tabas Block, east central Iran: Succesion of a failed-rift basin at the Paleotethys margin

    USGS Publications Warehouse

    Lasemi, Y.; Ghomashi, M.; Amin-Rasouli, H.; Kheradmand, A.

    2008-01-01

    The Lower Triassic Sorkh Shale Formation is a dominantly red colored marginal marine succession deposited in the north-south trending Tabas Basin of east central Iran. It is correlated with the unconformity-bounded lower limestone member of the Elika Formation of the Alborz Mountains of northern Iran. The Sorkh Shale is bounded by the pre-Triassic and post-Lower Triassic interregional unconformities and consists mainly of carbonates, sandstones, and evaporites with shale being a minor constituent. Detailed facies analysis of the Sorkh Shale Formation resulted in recognition of several genetically linked peritidal facies that are grouped into restricted subtidal, carbonate tidal flat, siliciclastic tidal flat, coastal plain and continental evaporite facies associations. These were deposited in a low energy, storm-dominated inner-ramp setting with a very gentle slope that fringed the Tabas Block of east central Iran and passed northward (present-day coordinates) into deeper water facies of the Paleotethys passive margin of northern Cimmerian Continent. Numerous carbonate storm beds containing well-rounded intraclasts, ooids and bioclasts of mixed fauna are present in the Sorkh Shale Formation of the northern Tabas Basin. The constituents of the storm beds are absent in the fair weather peritidal facies of the Sorkh Shale Formation, but are present throughout the lower limestone member of the Elika Formation. The Tabas Block, a part of the Cimmerian continent in east central Iran, is a rift basin that developed during Early Ordovician-Silurian Paleotethys rifting. Facies and sequence stratigraphic analyses of the Sorkh Shale Formation has revealed additional evidence supporting the Tabas Block as a failed rift basin related to the Paleotethys passive margin. Absence of constituents of the storm beds in the fair weather peritidal facies of the Sorkh Shale Formation, presence of the constituents of the storm beds in the fair weather facies of the Elika Formation (the

  9. Origin and time-space distribution of hydrothermal systems in east-central Australian sedimentary basins: Constraints from illite geochronology and isotope geochemistry.

    NASA Astrophysics Data System (ADS)

    Uysal, I. Tonguç

    2016-04-01

    Some well-known precious mineral deposits and hydrocarbon resources occur extensively in east-central Australian sedimentary Basins. The metal occurrences are abundant in northwestern and eastern part of Queensland, whereas no significant deposits are known in large areas further south, which may, however, be hidden beneath the Jurassic-Cretaceous sedimentary basins. Important hydrocarbon resources exist within the Jurassic-Cretaceous sedimentary rocks at relatively shallow depths, of which the distribution represent zones of high paleo-geothermal gradients. This study examines the time-space distribution in relation to the regional tectonic history of concealed metal deposits and areas of high paleo-geothermal gradient leading to hydrocarbon maturation. To this end, authigenic illitic clay minerals representing various locations and stratigraphic depths in east-central Australia were investigated, of which the Rb-Sr and Ar-Ar geochronology and stable isotope geochemistry assist in delineating zones of hydrothermal systems responsible for hydro-carbon maturation/migration and potentially ore deposition. The Late Carboniferous - Early Permian crustal extension that affected large areas of eastern Australia and led to the epithermal mineralisations (e.g., the Drummond Basin) is also recorded in northern South Australia and southwest Queensland. A Late Triassic - Early Jurassic tectonic event being responsible for coal maturation and gas generation in the Bowen Basin and the epithermal mineralisation in the North Arm goldfield in SE Queensland likewise affected the areas much further west in Queensland. Some illites from the basement in outback Queensland and fault gouges from the Demon Fault in NE New South Wales yield younger Rb-Sr and Ar-Ar ages indicating the effect of hydrothermal processes as a result of a Middle-Upper Jurassic tectonic event. The majority of illite samples from the crystalline basement rocks, Permian Cooper Basin, and Jurassic

  10. Hinterland tectonics and drainage evolution recorded by foreland basin archives: the Neogene Siwaliks of the Himalaya

    NASA Astrophysics Data System (ADS)

    Huyghe, Pascale; van der Beek, Peter; Matthias, Bernet; Catherine, Chauvel; Jean-Louis, Mugnier; Laurent, Husson; François, Chirouze

    2014-05-01

    Provenance analysis and detrital thermochronology of detrital synorogenic sediments, derived from erosion of mountain belts and deposited in surrounding sedimentary basins, are well-established methods to examine the exhumation history of convergent zones, tectonic activity and the associated evolution of the drainage network. We have conducted multidisciplinary studies on magnetostratigraphically dated sections throughout the Neogene Siwalik foreland basin of the Himalayan belt since more than 10 years. Sr, Nd and Hf isotopes are used as provenance indicators, providing information on the nature and size of catchment basins and their evolution through time in response to tectonics. Detrital zircon and apatite thermochronology provides constraints on exhumation rates in the hinterland of the Himalaya and the deformation of the Sub-Himalayan foreland basin. Throughout the Himalaya, detrital zircons from the Siwaliks generally show three age peaks: two static peaks (i.e., displaying constant peak ages through time), and a moving peak. The latter shows a constant lag time of ~4 m.y. corresponding to source-area exhumation rates on the order of 1.8 km/my, while the two static peaks respectively reveal a major 15-20 Ma exhumation event in the belt, the significance of which is still debated, and inheritance of pre-Himalayan ages that indicate recycling of Tethyan sediments. Therefore, our ZFT results suggest that the exhumation dynamics are broadly similar throughout the Himalaya since at least 13 m.y, as also shown by the Bengal Fan detrital sediment record. We relate this switch in tectonic regime to the destabilization of the Himalayan wedge that is rendered overcritical as a response to the transience of dynamic topography caused by the deforming underlying Indian slab. Nonetheless, in detail, the timing of thrusting in the Siwalik domain is delayed by about 1 my eastward as demonstrated by both structural and apatite fission-track data, suggesting overall eastward

  11. Mapping thermal maturity in the Chainman shale, near Eureka, Nevada, with Landsat Thematic Mapper images

    USGS Publications Warehouse

    Rowan, L.C.; Pawlewicz, M.J.; Jones, O.D.

    1992-01-01

    The purpose of this study was to determine if there is a correlation between measurements of organic matter (OM) maturity and laboratory measurements of visible and near-infrared spectral reflectance, and if Landsat Thematic Mapper (TM) images could be used to map maturity. The maturity of Mississippian Chainman Shale samples collected in east-central Nevada and west-central Utah was determined by using vitrinite reflectance and Rock-Eval pyrolysis. TM 4/TM 5 values correspond well to vitrinite reflectance and hydrogen index variations, and therefore this ratio was used to evaluate a TM image of the Eureka, Nevada, area for mapping thermal maturity differences in the Chainman Shale. -from Authors

  12. Cretaceous crustal structure and metamorphism in the hinterland of the Sevier thrust belt, western US Cordillera

    SciTech Connect

    Miller, E.L.; Gans, P.B. )

    1989-01-01

    Combined structural and geochronologic studies to the west of the Sevier belt at lat 39{degree}-40{degree}N indicate that peak metamorphism of the upper 15 km of crust occurred during the Late Cretaceous (70-90 Ma), overlapping in time with the intrusion of muscovite-bearing granites and pegmatites. Metamorphism was accompanied by penetrative deformation (top-to-the-east layer-parallel shear); both were localized at the currently exposed structural levels, resulting in impressive vertical and lateral strain gradients and T{sub max} gradients of > 50 C/km. Inception of thrust faulting in the Sevier belt may have predated peak metamorphism and intrusion of granites in the hinterland by 10-15 m.y., but it continued during and ended simultaneously with the end of metamorphism at about 70 Ma. The rise of muscovite-bearing granites and hot fluids, generated by metamorphism and crustal anatexis at greater depth, provides and explanation for the observed localized metamorphism and deformation at relatively high structural levels.

  13. Mesozoic and Cenozoic structures of Pocatello region: transition from thrust belt to hinterland, southeast Idaho

    SciTech Connect

    Burgel, W.D.; Rodgers, D.W.; Link, P.K.

    1987-08-01

    Remapping of upper Proterozoic and Cambrian rocks in the northern Bannock Range south and east of Pocatello, Idaho, indicates a polyphase deformation history characterized by both shortening and extension. Map-scale folds and faults, related to shortening in the transition zone between the Idaho-Wyoming thrust belt and the hinterland to the west, are present, but have been offset and rotated along superimposed normal faults. The oldest structure evident is the north-trending, east-vergent Rapid Creek fold. This fold involves upper Proterozoic and Cambrian strata in the hanging wall of the Putnam thrust fault. The fold is truncated by east-striking subvertical faults that are inferred to be coeval tear faults. Fold and fault geometries suggest the Rapid Creek fold formed over a footwall ramp, whose location may have been controlled by basement normal faults related to Proterozoic rifting. Further evidence of Mesozoic uplift lies in the sub-Neogene unconformity on Cambrian rocks in the Pocatello area, compared to areas of the thrust belt 15 km (9.3 mi) to the northeast, where similar tuffaceous strata rest on Triassic limestones, indicating 7 km (4.3 mi) of pre-Neogene erosion near Pocatello.

  14. [Effects of different irrigations on the water physiological characteristics of Haloxylon ammodendron in Taklimakan Desert hinterland].

    PubMed

    Xie, Ting-ting; Zhang, Xi-ming; Liang, Shao-min; Shan, Li-shan; Yang, Xiao-lin; Hua, Yong-hui

    2008-04-01

    By using heat-balance stem flow gauge and press chamber, the water physiological characteristics of Haloxylon ammodendron under different irrigations in Taklimakan Desert hinterland were measured and analyzed. The results indicated that the diurnal variation curve of H. ammodendron stem sap flow varied with irrigations. When irrigated 35 and 24.5 kg x plant(-1) once time, the diurnal variation of stem sap flow changed in single peak curve and the variation extent was higher; while irrigated 14 kg x plant(-1) once time, the diurnal variation changed in two-peak curve and the variation extent was small. With the decrease of irrigations, the average daily sap flow rate and the daily water consumption of H. ammodendron decreased gradually, the dawn and postmeridian water potential also had a gradual decrease, and the correlations of stem sap flow with total radiation, air temperature, relative humidity, and wind speed enhanced. Under different irrigations, the correlation between stem sap flow rate and total radiation was always the best. PMID:18593026

  15. Thrusting Rates in the Early Eocene from the Sevier Hinterland, Idaho, USA

    NASA Astrophysics Data System (ADS)

    Anastasio, D. J.; Latta, D.; Kodama, K. P.; Idleman, B. D.

    2011-12-01

    The terminal motion on the Wildhorse thrust system was reconstructed from the Smiley Creek Formation in eastern Idaho, USA (UTM coordinates 11T 739950 m E, 4865190 m N). During the last 100 m of fault slip the calculated slip rate varied between 0.05 to 1.2 mm/yr averaged over time intervals of 300-800 kyrs. The emergent thrust fault overrode proximal fault scarp colluvium deposited as water poor debris flows and was buried by braided stream sheet flood facies sourced by out-of-sequence thrust motion further west. Paleomagnetic data (~100 cores from 27 horizons spaced ~5-60 m apart) showed both normal and reversed directions during progressive step-wise thermal demagnetization to 670° C. Principal component analysis was used to calculate characteristic remanent magnetization directions from which sample polarities were assigned. Correlation of the Smiley Creek Formation to the Geomagnetic Polarity Timescale requires an age older than 49.39±0.27 (n=7) Ma determined by 40Ar/39Ar dating of overlying Challis Volcanic samples and younger than 57±9 Ma, the youngest U/Pb zircon age from an included andesite cobble from a near by Smiley Creek conglomerate exposure (11T 766548 m E, 4874382 m N). The favored magnetostratigraphic correlation is most consistent with expected terrestrial fan facies accumulation rates, the reversal pattern, and calculated paleopole positions. The 183 m of Smiley Creek Formation west of Stag Creek, Idaho was deposited in 4.48 myrs during polarity chrons 24.3n to 23n2n. The terminal emplacement of the Wildhorse thrust was associated with the development of the Pioneer Metamorphic Core complex in the hinterland of the Montana Recess of the Idaho-Wyoming-Montana thrust belt.

  16. Character of the Alleghanian orogeny in the hinterland of the southern Appalachians: Kinematics and tectonic models

    SciTech Connect

    Secor, D.T. Jr.; Pray, J.R.; West, T.E. Jr. . Dept. of Geological Sciences); Maher, H.D. Jr. . Dept. of Geography and Geology)

    1994-03-01

    Historically, an obvious manifestation of the Alleghanian orogeny has been the foreland fold and thrust belt and adjacent Carboniferous and Permian foreland basin along the northwest side of the Appalachians. However, evidence for Alleghanian tectonothermal activity in the Piedmont has gradually accumulated, and it is now clear that the hinterland preserves a rich and diverse record of the Alleghanian orogeny. In South Carolina and Georgia, the following events comprise the Alleghanian orogeny: (1) during c. 295--315 Ma, hot rocks of the Savannah River terrane were juxtaposed against cool rocks of the Carolina terrane by motion along the Modoc Fault; (2) following c. 295 Ma the eastern piedmont rocks were folded and thrust to the N26W along the gently dipping Box Ankle; (3) the Modoc and Box Ankle faults were truncated and/or overprinted by northeast trending dextral shear zones such as the Irmo (near vertical) and the Goat Rock (gently southeast dipping) prior to c. 275 Ma; (4) at c. 275 Ma, the gently southeast dipping Augusta normal fault juxtaposed shallow crustal rocks of the Augusta terrane against hotter deep crustal rocks of the Savannah River terrane. The above events are interpreted to be the result of a dextral transpressive collision between Laurentia and Gondwanna at the end of the Paleozoic. The Modoc fault may be the result of crustal delamination at the onset of collision, and the Augusta normal fault may indicate postorogenic collapse. The configuration of Alleghanian faults is reminiscent of the ''orogenic float'' hypothesis of Oldow and others (1990).

  17. Finding the Plateau: Paleogene Topography and Basin Formation in the Cordilleran Hinterland

    NASA Astrophysics Data System (ADS)

    Cassel, E. J.; Smith, M. E.; Canada, A.; Henry, C.; Breecker, D.

    2014-12-01

    In the US Cordilleran hinterland, Paleogene terrestrial strata independently constrain relative topography and provide information on the local depositional environment and regional drainage morphology necessary for interpreting stable isotope paleoaltimetry data. Volcanic glass hydration waters from fluvially interbedded ignimbrites record increasing δD values eastward from the paleo-coast, indicating that the region maintained demonstrably higher than modern elevations (3.5 +.7/-.3 km) through the Paleogene. This orogen had a distinct crest and continuous westward-draining slope extending to central California. To the east of this crest, Eocene strata consist of basal fluvial gravel conglomerate ≤ 200 m thick, overlain by interbedded fine-grained lacustrine strata up to 1 km thick, which record hydrologic closure. Conglomerates and sandstones display structures indicative of deposition primarily in gravel-bed braided rivers. Overlying interbedded laminated marl, siltstone, and carbonaceous mudstone containing abundant fossil flora, gastropods, and ostracods indicate a deep freshwater lacustrine depositional environment. Up section, alternating laminated kerogen-rich marl and calcareous mudstone, mud-cracked siltstone, stromatolites, and an absence of bioturbation record anoxic, saline bottom waters and fluctuating profundal to evaporative conditions. Tephras interbedded with lake strata have highly enriched δD values due to hydration by evaporative lake waters, supporting the interpretations that depositional environment controls δD values and that fully hydrated glass resists alteration on geologic timescales. Eocene stratigraphy indicates increased accommodation, continental drainage ponding, and basin closure. It is unlikely that local geomorphic damming provided the regionally extensive driver to create these deep, high elevation closed basins. Instead, migrating regional construction of topographic barriers resulting from the onset of extension and

  18. Geoenvironmental Investigations of the Humboldt River Basin, Northern Nevada

    USGS Publications Warehouse

    Stillings, Lisa L.

    2003-01-01

    Northern Nevada is one of the world's foremost regions of gold production. The Humboldt River Basin (HRB) covers 43,500 km2 in northern Nevada (Crompton, 1995), and it is home to approximately 18 active gold and silver mines (Driesner and Coyner, 2001) among at least 55 significant metallic mineral deposits (Long and others, 1998). Many of the gold mines are along the Carlin trend in the east-central portion of the HRB, and together they have produced 50 million ounces of gold from 1962 (when the Carlin mine first opened) through April 2002 (Nevada Mining Association, 2002). Mining is not new to the region, however. Beginning in 1849, mining has taken place in numerous districts that cover 39 percent of the land area in the HRB (Tingley, 1998). In addition to gold and silver, As, Ba, Cu, Fe, Hg, Li, Mn, Mo, Pb, S, Sb, V, W, Zn, and industrial commodities such as barite, limestone, fluorite, sand and gravel, gypsum, gemstones, pumice, zeolites, and building stone, have been extracted from the HRB (McFaul and others, 2000). All papers within this series of investigations can be found as lettered chapters of USGS Bulletin 2210, Geoenvironmental Investigations of the Humboldt River Basin, Northern Nevada. Each chapter is available separately online. The data and software utilized in this product (Chapter F) permit the user to view and analyze the geographic relationships among chemistry of stream sediments and surface waters, geology, and various cartographic base information such as but not limited to cities, county boundaries, and land ownership. Data for this product were compiled and or produced as part of a mineral and environmental assessment of the Humboldt River basin conducted by the U.S. Geological Survey between 1995 - 2000.

  19. Structural and kinematic evolution of the Yukon-Tanana upland tectonites, east-central Alaska: A record of late Paleozoic to Mesozoic crustal assembly

    USGS Publications Warehouse

    Hansen, V.L.; Dusel-Bacon, C.

    1998-01-01

    The Yukon-Tanana terrane, the largest tectonostratigraphic terrane in the northern North American Cordillera, is polygenetic and not a single terrane. Lineated and foliated (L-S) tectonites, which characterize the Yukon-Tanana terrane, record multiple deformations and formed at different times. We document the polyphase history recorded by L-S tectonites within the Yukon-Tanana upland, east-central Alaska. These upland tectonites compose a heterogeneous assemblage of deformed igneous and metamorphic rocks that form the Alaskan part of what has been called the Yukon-Tanana composite terrane. We build on previous kinematic data and establish the three-dimensional architecture of the upland tectonites through kinematic and structural analysis of more than 250 oriented samples, including quartz c-axis fabric analysis of 39 samples. Through this study we distinguish allochthonous tectonites from parautochthonous tectonites within the Yukon-Tanana upland. The upland tectonites define a regionally coherent stacking order: from bottom to top, they are lower plate North American parautochthonous attenuated continental margin; continentally derived marginal-basin strata; and upper plate ocean-basin and island-arc rocks, including some continental basement rocks. We delineate three major deformation events in time, space, and structural level across the upland from the United States-Canada border to Fairbanks, Alaska: (1) pre-Early Jurassic (>212 Ma) northeast-directed, apparent margin-normal contraction that affected oceanic rocks; (2) late Early to early Middle Jurassic (>188-185 Ma) northwest-directed, apparent margin-parallel contraction and imbrication that resulted in juxtaposition of the allochthonous tectonites with parautochthonous continental rocks; and (3) Early Cretaceous (135-110 Ma) southeast-directed crustal extension that resulted in exposure of the structurally deepest, parautochthonous continental rocks. The oldest event represents deformation within a west

  20. Blackburn field, Eureka County, Nevada: a case history

    SciTech Connect

    Scott, C.; Chamberlain, A.K.

    1987-08-01

    The Blackburn field lies along a late Mesozoic thrust-fault trend, in east-central Nevada. All production in Nevada is located along this thrust system, although traps are mostly Tertiary block-fault related. The thrust places porous Devonian carbonate reservoir rock over organic-rich Mississippian source rock. A Devonian fractured dolomitic limestone provides major production in the Blackburn field. Good intercrystalline shows are also evident. Another producing horizon - the Tertiary Indian Wells Formation - produces from porous, poorly consolidated tuffaceous sandstones and non-welded tuffs. Some production comes from fractured and intercrystalline porosity developed in Mississippian/Devonian arkosic sandstones, Gamma-ray signatures of the Mississippian-Devonian in Blackburn wells can be correlated along strike with surface gamma-ray signatures of measured sections in the Diamond Range. The apparently simple structure of the Blackburn field is interrupted by a fault on the western edge of the field. This fault can be seen on magnetic lines across the field, and in wells adjacent to it. Other minor faults also cut the field. The Blackburn field shows as a positive gravity anomaly, suggesting an inter-valley horst block.

  1. The communities of helminth parasites of Heterandria bimaculata (Teleostei: Poeciliidae) from the upper Río La Antigua basin, east-central Mexico show a predictable structure.

    PubMed

    Salgado-Maldonado, Guillermo; Novelo-Turcotte, María Teresa; Vazquez, Gabriela; Caspeta-Mandujano, Juan Manuel; Quiroz-Martínez, Benjamín; Favila, Mario

    2014-06-01

    We investigated a basic generalization in parasite community ecology stating that stochastic processes played a major part in determining the composition of helminth communities of freshwater fish, or on the contrary, if these communities are predictable, diverse and structured species assemblages. We determined the species pool of helminth parasites of a tropical freshwater fish Heterandria bimaculata in its heartland, the upper Río La Antigua basin in east-central Mexico. Approaching our data from the metapopulation standpoint we studied the spatial patterns, and examined the variation in composition and richness of the component communities across different locations. We tested the prediction that helminth species may be recognized as common or rare; and also two hypotheses anticipating depauperate communities and decay of similarity between component communities with increasing distance. We found these communities composed by a highly structured and predictable set of specialist autogenic helminth species that are constant and abundant, dominating all components throughout space. The prediction that it is possible to recognize common and rare species was met. Richer than expected communities were found, as well as highly homogeneous component communities, where neighbouring components were more similar than distant ones. We speculated that the processes shaping the development of these component communities include stable, predictable habitats through time, allowing for a slow gradual dispersion process limited by host and parasite species capabilities. Our study suggests that metapopulation theory can assist in the prediction of community composition and in the understanding of spatial and temporal community variability. PMID:24598076

  2. The second African Federation of Neurological Surgeons course in the East, Central, and Southern Africa region held in Dar es Salaam, Tanzania, January 2011.

    PubMed

    Kahamba, Joseph F; Assey, Anthony B; Dempsey, Robert J; Qureshi, Mahmood M; Härtl, Roger

    2013-01-01

    The second International African Federation of Neurological Surgeons course was organized on January 24 to 28, 2011, at the Seacliff Hotel and Muhimbili Orthopaedic Institute in Dar es Salaam, Tanzania. President Jakaya Mrisho Kikwete graced the official opening with high ranking government officials in attendance. The targeted participants were young neurosurgeons in the East, Central, and South African region. More than 80 surgeons, residents, and neurosurgical nurses came from Tanzania, Kenya, Uganda, Rwanda, Ethiopia, Zambia, and Zimbabwe. The objectives of the course were to teach and train young local surgeons in the essential-relevant for the region-and current techniques and management principles of brain and spinal diseases, acquire new skills through hands-on practical sessions, and share experiences. The course consisted of didactic sessions, practical aspects on spine internal fixation, cadaver dissections, and live microscopic and endoscopic surgery. Experienced faculty from different states of the United States, Spain, Turkey, India, Egypt, and Ethiopia facilitated the course. The objectives of the course were met with a favorable evaluation report. The collaboration and experience gained will be reinvested in organizing similar courses in the region. PMID:22120325

  3. Genesis and continuity of quaternary sand and gravel in glacigenic sediment at a proposed low-level radioactive waste disposal site in east-central Illinois

    USGS Publications Warehouse

    Troost, K.G.; Curry, B. Brandon

    1991-01-01

    The Illinois Department of Nuclear Safety has characterized the Martinsville Alternative Site (MAS) for a proposed low-level radioactive waste disposal facility. The MAS is located in east-central Illinois approximately 1.6 km (1 mi) north of the city of Martinsville. Geologic investigation of the 5.5-km2 (1380-acre) site revealed a sequence of chiefly Illinoian glacigenic sediments from 6 to 60 m (20-200 ft) thick overlying two major bedrock valleys carved in Pennsylvanian strata. Relatively permeable buried units include basal, preglacial alluvium; a complex of intraglacial and subglacial sediment; englacial deposits; and supraglacial fluvial deposits. Postglacial alluvium underlies stream valleys on and adjacent to the site. In most areas, the buried sand units are confined by low-permeability till, lacustrine sediment, colluvium, and loess. The distribution and thickness of the most extensive and continuous buried sand units have been modified considerably by subglacial erosion, and their distributions have been influenced by the buried bedrock valleys. The most continuous of the various sand units were deposited as preglacial and postglacial alluvium and are the uppermost and lowermost stratigraphic units at the alternative site. Sand units that were deposited in englacial or ice-marginal environments are less continuous. Aquifer pumping tests, potentiometric head data, and groundwater geochemistry analyses indicate minimal interaction of groundwater across localized interconnections of the permeable units. ?? 1991 Springer-Verlag New York Inc.

  4. Stratigraphy, fossils, and age of sediments at the upper pit of the Lost Chicken gold mine: new information on the late Pliocene environment of east central Alaska

    NASA Astrophysics Data System (ADS)

    Matthews, John V., Jr.; Westgate, J. A.; Ovenden, Lynn; Carter, L. David; Fouch, Thomas

    2003-07-01

    The "upper pit" at the Lost Chicken placer gold mine in east central Alaska contains fossils that provide information on the flora and insect fauna of interior Alaska just before the onset of global cooling at 2.5 myr. Fossils come from sediments interbedded with the Lost Chicken tephra (dated at 2.9 ± 0.4 myr—early Late Pliocene) and portray the floodplain and valley of a small creek within a region dominated by a coniferous forest richer in genera and species than the present one. Climate was wetter and less continental, and there was probably little or no permafrost. At least one other Pliocene tephra (the Fortymile tephra) occurs at the site and is also associated with plant and insect fossils. Among these fossils are extinct plants and insects like those found at other Tertiary sites in northern Canada and Alaska. The Lost Chicken sequence is the same age as the Beaufort Formation on Meighen Island, more than 1000 km to the north. Like Lost Chicken, Meighen Island sediments contain fossils representing a diverse boreal environment. This shows that the latitudinal climate gradient during early Late Pliocene time was shallower than at present and the boreal forest had a far greater latitudinal span than now.

  5. Correlation of coal beds in the Fruitland Formation as interpreted from geophysical logs, east-central San Juan County, New Mexico

    USGS Publications Warehouse

    Sandberg, Dorothy T.

    1986-01-01

    Correlation of coal beds in the Fruitland Formation (Upper Cretaceous) in the subsurface, from interpretation of geophysical logs, is an outgrowth of unpublished studies of deep coal on the Navajo Reservation by the author in the Toadlena 30 x 60 minute quadrangle, New Mexico, and by W. J. Mapel in the Farmington 30 x 60 minute quadrangle, New Mexico.  The lines of sections of this report extend eastward from the reservation into east-central San Juan County, which is in the western part of the San Juan Basin.  In this area, the rocks dip gently northeast toward the central part of the basin.  The thick coal is less than 1,500 feet beneath the surface.  Of the 53 logs in the sections, 48 are from oil- and gas-test holes, and 5 are from coal-test holes (see table 1).  Stratigraphic relations of the Upper Cretaceous Lewis Shale, Pictured Cliffs Sandstone, and Fruitland Formation, shown on the cross sections and briefly reviewed below, have been previously described for this or other parts of the San Juan Basin by Hayes and Zapp (1955), Beaumont (1971), Fassett and hinds (1971), O;Sullivan and other (1972), and Molenaar (1983), among others.

  6. Computer simulation of the steady-state flow system of the Tertiary limestone (Floridan) aquifer system in east-central Florida

    USGS Publications Warehouse

    Tibbals, C.H.

    1981-01-01

    The predevelopment steady-state ground-water flow system for 13 ,700 square miles of the Tertiary limestone aquifer system (known as the Florida aquifer in Florida) in east-central Florida is simulated by means of a digital computer model. The model results indicate that about 1,900 cubic feet per second recharges the aquifer as downward leakage from the surficial aquifer. The average recharge rate where recharge actually occurs (approximately 6,550 square miles) is about 4 inches per year. The maximum recharge rate is about 14 inches per year. An additional 21 cubic feet per second is recharged to the modeled area of the aquifer by means of lateral boundary inflow along the northeast boundary. The Floridan aquifer system, as simulated, discharges 1,300 cubic feet per second as springflow, 540 cubic feet per second as diffuse upward leakage to the surficial aquifer in an area of approximately 7,150 square miles and 81 cubic feet per second as lateral boundary outflow to the southwest and to the east. The average transmissivity of the upper unit of the aquifer, as simulated, is about 120,000 square feet per day while that for the lower unit is about 60,000 square feet per day. (USGS)

  7. [Studies on the incidence of echinococcus multilocularis in red foxes (Vulpes vulpes) in north-east, central and south of Poland].

    PubMed

    Rocki, B; Malczewski, A; Eckert, J

    1999-01-01

    During the year 1994-1997, a total number of 1042 red foxes orginating from the 33 provinces North-East, Central and South of Poland under special safety procautions for intestinal stages of Echinococcus multilocularis using the mucosal-smer technique were examined. An average of 5.09% (53 foxes) from 10 provinces was infected. In those provinces, the prevalance varied between 1.19% to 35.71%. The infection varied from low to very high but mostly harboured gravid E. multilocularis parasites with thick-shelled eggs. Our data indicate that E. multilocularis in foxes has a surprisingly wide distribution in Poland. These new epidemiological data indicate that a potential risk of infection for humans may exists in all areas where foxes infected with E. multilocularis have been identified. It has been assumed that E. multilocularis might also occur in other provinces in which foxes examination have not yet been undertaken or number examined of animals was low. This study was supported by a two grands from the Swiss National Foundation (projects No 7PLPJ038414 and 7PLPJ041302). PMID:16886382

  8. Characterization and Evaluation of Acid Rain in East Central Florida from 1978 to 1995 and Evaluation of Some Chromatographic/Spectroscopic Results from Leachate Samples from CELSS

    NASA Technical Reports Server (NTRS)

    Madsen, Brooks C.

    1996-01-01

    The results of monitoring the chemical composition of rain in east-central Florida have shown that the rain is moderately acid. The measured acidity of rain is less than that observed in other regions of the U. S., however, it does suggest that the level of acidity is substantial. The annual chemical composition of rain at UCF and at KSC has shown moderate variability. Extreme daily and monthly variations are observed, however these variations are not addressed here. The total ionic composition of rain collected at FL99 is greater than that for rain collected at UCF, however this can be accounted for by site proximity to the ocean with the accompanying marine influence. Difference in acidity data collected from the UCF and FL99 sites which are separated by 50 km may be due in part to the differences that have been observed between laboratory and field pH measurements. Trend assessment for precipitation composition requires evaluation of data that covers some minimum time period. In fact, the subdivision of the multi-year UCF record into individual 10 year records as described above can lead to the conclusion that a significant increase, a significant decrease or no trend exists for acidity depending upon the time period chosen for evaluation. Trend evaluation has also been accomplished by linear and nonlinear regression analysis using monthly volume weighted average concentrations and deposition using the UCF data set and some of the Florida NADP data set.

  9. The origin of grasslands in the temperate forest zone of east-central Europe: long-term legacy of climate and human impact

    NASA Astrophysics Data System (ADS)

    Kuneš, Petr; Svobodová-Svitavská, Helena; Kolář, Jan; Hajnalová, Mária; Abraham, Vojtěch; Macek, Martin; Tkáč, Peter; Szabó, Péter

    2015-05-01

    The post-glacial fate of central European grasslands has stimulated palaeoecological debates for a century. Some argued for the continuous survival of open land, while others claimed that closed forest had developed during the Middle Holocene. The reasons behind stability or changes in the proportion of open land are also unclear. We aim to reconstruct regional vegetation openness and test the effects of climate and human impact on vegetation change throughout the Holocene. We present a newly dated pollen record from north-western fringes of the Pannonian Plain, east-central Europe, and reconstruct Holocene regional vegetation development by the REVEALS model for 27 pollen-equivalent taxa. Estimated vegetation is correlated in the same area with a human activity model based on all available archaeological information and a macrophysical climate model. The palaeovegetation record indicates the continuous presence of open land throughout the Holocene. Grasslands and open woodlands were probably maintained by local arid climatic conditions during the early Holocene delaying the spread of deciduous (oak) forests. Significantly detectable human-made landscape transformation started only after 2000 BC. Our analyses suggest that Neolithic people spread into a landscape that was already open. Humans probably contributed to the spread of oak, and influenced the dynamics of hazel and hornbeam.

  10. POSSIBLE LATE MIDDLE ORDOVICIAN ORGANIC CARBON ISOTOPE EXCURSION: EVIDENCE FROM ORDOVICIAN OILS AND HYDROCARBON SOURCE ROCKS, MID-CONTINENT AND EAST-CENTRAL UNITED STATES.

    USGS Publications Warehouse

    Hatch, Joseph R.; Jacobson, Stephen R.; Witzke, Brian J.; Risatti, J. Bruno; Anders, Donald E.; Watney, W. Lynn; Newell, K. David; Vuletich, April K.

    1987-01-01

    Oils generated by Middle Ordovician rocks are found throughout the Mid-Continent and east-central regions of the United States. Gas chromatographic characteristics of these oils include a relatively high abundance of n-alkanes with carbon numbers less than 20, a strong predominance of odd-numbered n-alkanes between C//1//0 and C//2//0, and relatively small amounts of branched and cyclic alkanes. The wide ranges in delta **1**3C for oils and rock extracts reflect a major, positive excursion(s) in organic matter delta **1**3C in late Middle Ordovician rocks. This excursion has at least regional significance in that it can be documented in sections 480 mi apart in south-central Kansas and eastern Iowa. The distance may be as much as 930 mi. The parallel shifts in organic and carbonate delta **1**3C in core samples from 1 E. M. Greene well, Washington County, Iowa, imply changes in the isotope composition of the ocean-atmosphere carbon reservoir. These and other aspects of the subject are discussed.

  11. Land cover change monitoring within the east central Louisiana study site: A case for large area surveys with LANDSAT multispectral scanner data

    NASA Technical Reports Server (NTRS)

    Burns, G. S.

    1983-01-01

    Results established for four digital procedures developed for characterizing the radiometric changes between multidate LANDSAT spectral data sets into meaningful measures of land cover/use dynamics are documented. Each technique's performance was contrasted against digitized land use change maps, which were produced from contemporaneous, retrospective aerophoto coverage, in a cell by cell comparison over a one half by one degree area in east central Louisiana as a standard for comparison. The four techniques identify from 10.5 to 13.0% loss in area of forestland in a five year period; however, they differ more by how accurately this amount of change is distributed, the need for ancillary ground truth, and amount of usable information that is extractable. All require some method of digitally co-registering the two data sets. All are capable of providing tabular statistics as well as map products. Two are capable of detecting changes and identifying their locations. The other two, in addition to this, provide information to qualify land cover conditions at each end of the study interval.

  12. Reservoir characteristics of two minter oil sands based on continuous core, E-logs, and geochemical data: Bee Brake field, East-Central Louisiana

    SciTech Connect

    Echols, J.B.; Goddard, D.A.; Bouma, A. )

    1993-09-01

    The Bee Brake field area, located in township 4N/6E and 4N/7E in Concordia Parish, has been one of the more prolific oil-producing areas in east-central Louisiana. Production decline in various fields, however, has sparked interest in the economic feasibility of locating and producing the remaining bypassed oil in the lower Wilcox. For this purpose, the Angelina BBF No. 1 well was drilled, and a 500-ft conventional core and a complete suite of state-of-the-are wireline logs were recovered. Production tests were run on the Minter interval of interest. The 16-ft Minter interval (6742-6758 ft depth), bounded at its top and base by lignite seams, consists of an upper 4-ft oil sand (Bee Brake) and a lower 3-ft oil sand (Angelina). The oil sands are separated by approximately 5 ft of thinly laminated silty shale and 4 ft of very fine-grained silty sandstone. Detailed sedimentologic and petrographic descriptions of the Minter interval provide accurate facies determinations of this lower delta-plain sequence. Petrophysical evaluation, combining core plug and modern electric-log data show differences between reservoir quality of the Bee Brake and Angelina sands. This data will also be useful for correlating and interpolating old electric logs. Organic geochemistry of the oil, lignites, and shales provides insight as to the source of the Minter oils and the sourcing potential of the lignites.

  13. Depth to water, 1991, in the Rathdrum Prairie, Idaho; Spokane River valley, Washington; Moscow-Lewiston-Grangeville area, Idaho; and selected intermontane valleys, east-central Idaho

    USGS Publications Warehouse

    Berenbrock, Charles E.; Bassick, M.D.; Rogers, T.L.; Garcia, S.P.

    1995-01-01

    This map report illustrates digitally generated depth-to-water zones for the Rathdrum Prairie in Idaho; part of the Spokane River Valley in eastern Washington; and the intermontane valleys of the upper Big Wood, Big Lost, Pahsimeroi, Little Lost, and Lemhi Rivers and Birch Creek in Idaho. Depth to water is 400 to 500 feet below land surface in the northern part of Rathdrum Prairie, 100 to 200 feet below land surface at the Idaho-Washington State line, and 0 to 250 feet below land surface in the Spokane area. Depth to water in the intermontane valleys in east-central Idaho is least (usually less than 50 feet) near streams and increases toward valley margins where mountain-front alluvial fans have formed. Depths to water shown in the Moscow-Lewiston-Grangeville area in Idaho are limited to point data at individual wells because most of the water levels measured were not representative of levels in the uppermost aquifer but of levels in deeper aquifers.

  14. Segmentation and the coseismic behavior of basin and range normal faults. Examples from east-central Idaho and southwestern Montana, USA

    USGS Publications Warehouse

    Crone, Anthony J.; Haller, Kathleen M.

    1991-01-01

    The range-front normal faults of the Lost River and Lemhi Ranges, and the Beaverhead and Tendoy Mountains in east-central Idaho and southwestern Montana have well-preserved fault scarps on Quaternary deposits along much of their lengths. Fault-scarp morphology, the age of deposits displaced by the faults, and the morphology of the range fronts provide a basis for dividing the faults into segments that are typically 20-25 km long. Four characteristics are recognized that help to identify segment boundaries: (1) major en echelon offsets or pronounced gaps in the continuity of fault scarps; (2) distinct, persistent, along-strike changes in fault-scarp morphology that indicate different ages of faulting; (3) major salients in the range front; and (4) transverse bedrock ridges where the cumulative throw is low compared to other places along the fault zone. Only features whose size is measured on the scale of kilometers are regarded as significant enough to represent a segment boundary that could inhibit or halt a propagating rupture. The ability to identify segments of faults that are likely to behave as independent structural entities will improve seismic-hazard assessment. However, one should not assume that the barriers at segment boundaries will completely stop all propagating ruptures.

  15. Carbonate cementation as related to the diagenesis of clay in a mixed siliciclastic-carbonate system: Examples from the Centerfield biostrome, east central Pennsylvania

    SciTech Connect

    Burns, C.D. )

    1994-03-01

    The Middle Devonian Mahantango Formation consists of siliciclastic and mixed carbonate-siliciclastic sediment packages that pulse in and out of the stratigraphy. The formation crops out in several places throughout the folded rocks of eastern Pennsylvania and Maryland. The Centerfield Member is one of the mixed siliciclastic-carbonate packages in the Mahantango Fm. This member crops out in east central Pennsylvania. The Centerfield Mbr. has been interpreted as a series of biostromes and contain abundant rugosan corals, crinoids, bryozoans, and brachiopods. The biostromes have undergone a complex diagenetic history. Illite, smectite, chlorite and muscovite have been found with the use of powder x-ray diffraction and petrographic analysis. The smectite and some of the illite are depositional clays, while, the remaining illite, chlorite and muscovite represent recrystallization of the depositional clays. There are six phases of cement in the biostrome. The paragenetic sequence of the cements is as follows: non-ferroan low magnesian calcite (LMC), intermediate ferroan LMC, ferroan LMC, non-ferroan dolomite, ferroan baroque dolomite, and quartz cement in the form of chert and blocky cement. Staining shows that the iron content of the cement changes within individual crystals and between cement phases. Preliminary data suggest that the cements may be directly related to the steady release of ions during the diagenesis of the surrounding clays in the shale.

  16. An alternative hypothesis for the mid-Paleozoic Antler orogeny in Nevada

    USGS Publications Warehouse

    Ketner, Keith B.

    2012-01-01

    A great volume of Mississippian orogenic deposits supports the concept of a mid-Paleozoic orogeny in Nevada, and the existence and timing of that event are not questioned here. The nature of the orogeny is problematic, however, and new ideas are called for. The cause of the Antler orogeny, long ascribed to plate convergence, is here attributed to left-lateral north-south strike-slip faulting in northwestern Nevada. The stratigraphic evidence originally provided in support of an associated regional thrust fault, the Roberts Mountains thrust, is now known to be invalid, and abundant, detailed map evidence testifies to post-Antler ages of virtually all large folds and thrust faults in the region. The Antler orogeny was not characterized by obduction of the Roberts Mountains allochthon; rocks composing the "allochthon" essentially were deposited in situ. Instead, the orogeny was characterized by appearance of an elongate north-northeast-trending uplift through central Nevada and by two parallel flanking depressions. The eastern depression was the Antler foreland trough, into which sediments flowed from both east and west in the Mississippian. The western depression was the Antler hinterland trough into which sediments also flowed from both east and west during the Mississippian. West of the hinterland trough, across a left-lateral strike-slip fault, an exotic landmass originally attached to the northwestern part of the North American continent was moved southward 1700 km along a strike-slip fault. An array of isolated blocks of shelf carbonate rocks, long thought to be autochthonous exposures in windows of the Roberts Mountains allochthon, is proposed here as an array of gravity-driven slide blocks dislodged from the shelf, probably initiated by the Late Devonian Alamo impact event.

  17. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah

    USGS Publications Warehouse

    Welch, Alan H., (Edited By); Bright, Daniel J.; Knochenmus, Lari A.

    2008-01-01

    INTRODUCTION This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 301(e) of the Lincoln County Conservation, Recreation, and Development Act of 2004; PL108-424) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins are the subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas are the subdivision used for reporting summed and tabulated subbasin estimates.

  18. Water Resources of the Basin and Range Carbonate-Rock Aquifer System, White Pine County, Nevada, and Adjacent Areas in Nevada and Utah - Draft Report

    USGS Publications Warehouse

    Welch, Alan H., (Edited By); Bright, Daniel J.

    2007-01-01

    Summary of Major Findings This report summarizes results of a water-resources study for White Pine County, Nevada, and adjacent areas in east-central Nevada and western Utah. The Basin and Range carbonate-rock aquifer system (BARCAS) study was initiated in December 2004 through Federal legislation (Section 131 of the Lincoln County Conservation, Recreation, and Development Act of 2004) directing the Secretary of the Interior to complete a water-resources study through the U.S. Geological Survey, Desert Research Institute, and State of Utah. The study was designed as a regional water-resource assessment, with particular emphasis on summarizing the hydrogeologic framework and hydrologic processes that influence ground-water resources. The study area includes 13 hydrographic areas that cover most of White Pine County; in this report however, results for the northern and central parts of Little Smoky Valley were combined and presented as one hydrographic area. Hydrographic areas are the basic geographic units used by the State of Nevada and Utah and local agencies for water-resource planning and management, and are commonly defined on the basis of surface-water drainage areas. Hydrographic areas were further divided into subbasins that are separated by areas where bedrock is at or near the land surface. Subbasins represent subdivisions used in this study for estimating recharge, discharge, and water budget. Hydrographic areas represent the subdivision used for reporting summed and tabulated subbasin estimates.

  19. Blackburn field, Eureka County, Nevada: a cast history

    SciTech Connect

    Scott, C.; Chamberlain, A.K.

    1987-05-01

    The Blackburn field lies along a late Mesozoic thrust-fault trend in east-central Nevada. All Nevada production is located along this thrust system, although traps are mostly Tertiary block-fault related. The thrust places porous Devonian carbonates reservoir rock over organic-rich Mississippian source rock. A Devonian fractured dolomitic limestone provides major production in the Blackburn field. Good intercrystalline shows are also evident. Some production comes from fractured and intercrystalline porosity developed in Mississippian/Devonian arkosic sandstones. Another producing horizon, the Tertiary Indian Wells formation, produces from porous, poorly consolidated tuffaceous sandstones and nonwelded tuffs. Gamma-ray signatures of the Mississippian-Devonian in Blackburn wells can be correlated along strike with surface gamma-ray signatures of measured sections in the Diamond Range. These gamma-ray correlations, in addition to detailed cuttings description and interpretation of well-log data, have prompted correlation of limestone and sandstone units in the lower part of the Blackburn field. Adequate seals are a major concern in eastern Nevada. Mississippian/Devonian shales provide seal for Paleozoic limestone and sandstone reservoirs, while welded tuff traps oil in poorly consolidated tuffaceous sandstones of the Tertiary Indian Wells formation. The apparent simple structure of the Blackburn field is interrupted by a fault on the western edge of the field. This fault can be seen on magnetic lines across the field and in wells adjacent to it. Other minor faults also cut the field. The Blackburn field shows as a positive gravity anomaly, suggesting an intervalley horst block.

  20. Influence of Trap Height and Bait Type on Abundance and Species Diversity of Cerambycid Beetles Captured in Forests of East-Central Illinois.

    PubMed

    Schmeelk, Thomas C; Millar, Jocelyn G; Hanks, Lawrence M

    2016-08-01

    We assessed how height of panel traps above the forest floor, and the type of trap bait used, influenced the abundance and diversity of cerambycid beetles caught in forested areas of east-central Illinois. Panel traps were suspended from branches of hardwood trees at three heights above the ground: understory (∼1.5 m), lower canopy (∼6 m), and midcanopy (∼12 m). Traps were baited with either a multispecies blend of synthesized cerambycid pheromones or a fermenting bait mixture. Traps captured a total of 848 beetles of 50 species in the cerambycid subfamilies Cerambycinae, Lamiinae, Lepturinae, and Parandrinae, and one species in the closely related family Disteniidae. The species caught in highest numbers was the cerambycine Anelaphus pumilus (Newman), represented by 349 specimens. The 17 most abundant species (mean ± 1 SD: 45 ± 80 specimens per species) included 12 cerambycine and five lamiine species. Of these most abundant species, 13 (77%) were attracted to traps baited with the pheromone blend. Only the cerambycine Eburia quadrigeminata (Say) was attracted by the fermenting bait. Three species were captured primarily in understory traps, and another five species primarily in midcanopy traps. Variation among cerambycid species in their vertical distribution in forests accounted for similar overall abundances and species richness across trap height treatments. These findings suggest that trapping surveys of native communities of cerambycids, and quarantine surveillance for newly introduced exotic species, would be optimized by including a variety of trap baits and distributing traps across vertical strata of forests. PMID:27298428

  1. Cratonic platform and foredeep response to plate margin convergence: Devonian through Mississippian subsidence history in western Montana and east-central Idaho

    SciTech Connect

    Dorobek, S.L.; Reid, S.K. ); Elrich, M. ); Bond, G.C. ); Kominz, M.A. )

    1990-05-01

    Devonian and Mississippian sedimentary rocks of western Montana and east-central Idaho were deposited on a cratonic platform that faced a northern extension of the Antler foredeep. Subsidence analyses of this sequence and isopach maps illustrate regional patterns of subsidence related to convergence along the western North American plate margin. Tectonic stresses affected deposition on platform areas which were hundreds of kilometers inboard from the ancient continental margin. Wavelengths of paleostructural elements, tectonic inversion of these structures (i.e., transition of a paleohigh into a depocenter), and time scales involved in the inversion process cannot be attributed solely to flexure or to vertical displacements by in-plane stresses but suggest reactivation of Precambrian structural trends. Late Devonian (Frasnian) platform sedimentation began during a brief interval of increased subsidence across western Montana. This interval of increased platform subsidence is greater than a Late Devonian eustatic sea level rise (determined from subsidence analyses of Devonian strata from stable cratonic areas) and suggests some tectonic event must have influenced subsidence in Montana. Thin uppermost Devonian Strata contain numerous unconformities that may be related to flexure of the platform plus eustatic sea level fluctuations. Rapid subsidence across Montana during the Early Mississippian (Kinderhookian) resulted in a condensed platform sequence, which is overlain by deep water shaly carbonates. Rapid subsidence continued into the Osagean then slowed, allowing progradation of carbonate platform facies across Montana. A regional karst surface on top of the Meramecian platform coincides with conglomerate deposition and increased subsidence rates in the foredeep; unconformity durations on the platform also increase to the east.

  2. Kriging of Eocene sand channels from depth-averaged overburden pH, Jewett lignite surface mine, east-central Texas

    SciTech Connect

    Altis, S.; Tilford, N.R.

    1995-12-01

    Ordinary point kriging was used to map twenty-six vertically-averaged soil and oxidized overburden acidity values for a future mine block at the Jewett lignite mine, east-central Texas. The pH data were collected as part of a geochemical overburden characterization study to be used in post-mining reclamation decision-making. The authors used kriging, and its estimation standard error, to test the completeness of their data set and to indicate areas of need for additional closely spaced sampling. Because pH can be readily measured in the field, they chose it as the parameter of interest in the kriging. In general pH increased with depth; however, a more exciting result was that the trend and geometry of a major paleo-channel could be mapped from pH values because of the relatively higher acidity of the sand in the channel. Kriged maps were compared with manually-contoured and inverse-distance weighting interpolated maps, and found to be more easily interpretable. The kriging performed better because it allows of anisotropies in the data to be naturally included in the interpolation. Prior to the kriging, the data were studied to validate the assumptions involved in the modeling. The data are clean, well-behaved and statistically homogeneous, and the interpolation was successful even with sparse data. The knowledge of the location and morphology of the paleochannels is essential for the engineering aspects of the mining, and is useful in reclamation decision-making.

  3. Transit losses and traveltimes for reservoirs releases during drought conditions along the Neosho River from Council Grove Lake to Iola, east-central Kansas

    USGS Publications Warehouse

    Carswell, W.J.; Hart, R.J.

    1985-01-01

    Knowledge of the transit losses and water-wave traveltimes in the Neosho River for varying reservoir-release volumes and durations is necessary for proper management of water supply. Two reaches were studied along the Neosho River in east-central Kansas. The upper reach is from Council Grove Lake to John Redmond Reservoir, a distance of 83.0 river miles. The lower reach is from John Redmond Reservoir to Iola, Kansas, a distance of 56.3 river miles. Channel and aquifer characteristics were estimated from available data and used in a streamflow routing model. These estimated characteristics were verified using the model by comparing simulated reservoir releases to observed reservoir releases. The verified model then was used to simulate transit losses (or gains) and traveltimes for selected reservoir release volumes and durations from Council Grove Lake to Iola. Transit losses and traveltimes were investigated for the selected reservoir releases while under a severe drought antecedent streamflow condition (zero base flow) and a less severe drought antecedent streamflow condition (2% drought base flows). The largest total transit loss from Council Grove Lake to Iola occurred during the severe drought antecedent streamflow condition, small reservoir release rates, and long reservoir release durations. The total transit loss included water that was temporarily lost to bank storage. For a severe drought condition, transit losses ranged from 1,100 acre-ft for a release volume of 1,840 acre-ft for a duration of 50 days to 6 ,280 acre-ft for a release volume of 6,280 acre-ft for a duration of 365 days. For a less severe drought condition, transit losses ranged from 860 acre-ft to 3,234 acre-ft for the same release volumes and durations as for the severe drought condition. (Author 's abstract)

  4. Segmentation and the coseismic behavior of Basin and Range normal faults: examples from east-central Idaho and southwestern Montana, U.S.A.

    USGS Publications Warehouse

    Crone, A.J.; Haller, K.M.

    1991-01-01

    The range-front normal faults of the Lost River and Lemhi Ranges, and the Beaverhead and Tendoy Mountains in east-central Idaho and southwestern Montana have well-preserved fault scarps on Quaternary deposits along much of their lengths. Fault-scarp morphology, the age of deposits displaced by the faults, and the morphology of the range fronts provide a basis for dividing the faults into segments that are typically 20-25 km long. The Lost River, Lemhi and Beaverhead fault zones are 141-151 km long, and each has six segments. The 60-km-long Red Rock fault (the range-front fault of the Tendoy Mountains) has two central segments that have been active in late Quaternary time; these two segments span the central 27 km of the fault. We recognize four characteristics that help to identify segment boundaries: (1) major en e??chelon offsets or pronounced gaps in the continuity of fault scarps; (2) distinct, persistent, along-strike changes in fault-scarp morphology that indicate different ages of faulting; (3) major salients in the range front; and (4) transverse bedrock ridges where the cumulative throw is low compared to other places along the fault zone. Only features whose size is measured on the scale of kilometers are regarded as significant enough to represent a segment boundary that could inhibit or halt a propagating rupture. The ability to identify segments of faults that are likely to behave as independent structural entities will improve seismic-hazard assessment. However, one should not assume that the barriers at segment boundaries will completely stop all propagating ruptures. The topographic expression of mountain ranges is evidence that, at times during their history, all barriers fail. Some barriers apparently create 'leaky' segment boundaries that impede propagating ruptures but do not completely prevent faulting on adjacent segments. ?? 1991.

  5. The diversity of permafrost-affected soils in the Lena River Delta and its hinterland

    NASA Astrophysics Data System (ADS)

    Zubrzycki, Sebastian; Kutzbach, Lars; Yakshina, Irina; Pfeiffer, Eva-Maria

    2013-04-01

    , the Holocene river terrace of the delta is in its main extent covered by a soil complex of Glacic Aquiturbels and Typic Historthels. The active floodplain levels are dominated by sandy or gleyic subgroups of the Orthel suborder as e.g. Psammentic Aquorthels or Typic Psammorthels. The surfaces of the Arga-Muora-Sise Island are frequently reshaped by aeolian sedimentation and erosion. The soils on these scarcely vegetated landscapes are dominated by cryoturbated and sand-rich soil subgroups with high moisture contents, e.g., various Psammoturbels and Aquiturbels. The modern soils covering the older Pleistocene ice-complex plains are influenced by wide ice-wedge net structures and consist of a soil complex of Glacic Aquiturbels and Ruptic Historthels. The widespread thermokarst depressions within the ice-complex are covered by Ruptic Histoturbels and Ruptic Historthels, whereas the slopes are dominated by various Aquiturbels and Fluvaquentic Historthels. For the largely unexplored Lena River Delta's hinterland it can be assumed that the active genesis of the soils lasts longer than in the active delta regions due to a much lower sedimentation and more stable surface conditions. In these regions widespread cryoturbated and peat-rich soil groups like Histoturbels and Historthels as well as Fibristels are found. An increased understanding of spatial variability and genesis of permafrost-affected soils is essential for meaningful predictions of climate change consequences in Arctic permafrost regions.

  6. Cryosols of the Northeast Siberian Lena River Delta and its hinterland - genesis and diversity

    NASA Astrophysics Data System (ADS)

    Zubrzycki, Sebastian; Kutzbach, Lars; Pfeiffer, Eva-Maria

    2016-04-01

    of the delta is in its main extent covered by a soil complex of Glaci-Turbic Cryosols and Hapli-Histic Cryosols. The active floodplain levels are dominated by sandy or gleyic Fluvi Gleyic Cryosols or Areni Fluvic Cryosols. The surfaces of the Arga-Muora-Sise Island are frequently reshaped by aeolian sedimentation and erosion. The soils on these scarcely vegetated landscapes are dominated by cryoturbated and sand-rich soils with high moisture contents, e.g., various Areni-Turbic Cryosols and Aqui-Turbic Cryosols. The modern soils covering the older Pleistocene ice-complex plains are influenced by wide ice-wedge net structures and consist of a soil complex of Glaci-Turbic Cryosols and Gleyi-Histic Cryosols. The widespread thermokarst depressions within the ice-complex are covered by Histi-Turbic Cryosols and Gleyi-Histic Cryosols, whereas the slopes are dominated by Aqui-Turbic Cryosols and Gleyi-Cryic Cryosols. For the largely unexplored hinterland of LRD it can be assumed that the active genesis of the soils lasts longer than in the active delta regions due to a much lower sedimentation and more stable surface conditions. In these regions widespread cryoturbated and peat-rich soils like Histi-Turbic Cryosols and Histic Cryosols. An increased understanding of spatial variability and genesis of permafrost-affected soils is essential for meaningful predictions of climate change consequences in Arctic permafrost regions.

  7. Contributions to Astrogeology: Geology of the lunar crater volcanic field, Nye County, Nevada

    NASA Technical Reports Server (NTRS)

    Scott, D. H.; Trask, N. J.

    1971-01-01

    The Lunar Crater volcanic field in east-central Nevada includes cinder cones, maars, and basalt flows of probably Quaternary age that individually and as a group resemble some features on the moon. Three episodes of volcanism are separated by intervals of relative dormancy and erosion. Changes in morphology of cinder cones, degree of weathering, and superposition of associated basalt flows provide a basis for determining the relative ages of the cones. A method has been devised whereby cone heights, base radii, and angles of slope are used to determine semiquantitatively the age relationships of some cinder cones. Structural studies show that cone and crater chains and their associated lava flows developed along fissures and normal faults produced by tensional stress. The petrography of the basalts and pyroclastics suggests magmatic differentiation at depth which produced interbedded subalkaline basalts, alkali-olivine basalts, and basanitoids. The youngest flows in the field are basanitoids.

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

    PubMed

    Li, Qiang; Wang, Xiaoming

    2015-01-01

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

  9. Trace metal distribution in pristine permafrost-affected soils of the Lena River delta and its hinterland, northern Siberia, Russia

    NASA Astrophysics Data System (ADS)

    Antcibor, I.; Eschenbach, A.; Zubrzycki, S.; Kutzbach, L.; Bolshiyanov, D.; Pfeiffer, E.-M.

    2014-01-01

    Soils are an important compartment of ecosystems and have the ability to buffer and immobilize substances of natural and anthropogenic origin to prevent their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since Arctic ecosystems are considered to be highly sensitive to climatic changes as well as to chemical contamination. This study characterises background levels of trace metals in permafrost-affected soils of the Lena River delta and its hinterland in northern Siberia (73.5-69.5° N), representing a remote region far from evident anthropogenic trace metal sources. Investigations on the element content of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co), and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest median concentrations of Fe and Mn were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) while the highest median values of Ni, Pb and Zn were found in soils of both the ice-complex and the Holocene estuarine terrace of the Lena River delta region, as well as in the southernmost study unit of the hinterland area. Detailed observations of trace metal distribution on the micro scale showed that organic matter content, soil texture and iron-oxide contents influenced by cryogenic processes, temperature, and hydrological regimes are the most important factors determining the metal abundance in permafrost-affected soils. The observed range of trace element background concentrations was similar to trace metal levels reported for other pristine northern areas.

  10. Trace-element geochemistry of metabasaltic rocks from the Yukon-Tanana Upland and implications for the origin of tectonic assemblages in east-central Alaska

    USGS Publications Warehouse

    Dusel-Bacon, C.; Cooper, K.M.

    1999-01-01

    We present major- and trace- element geochemical data for 27 amphibolites and six greenstones from three structural packages in the Yukon-Tanana Upland of east-central Alaska: the Lake George assemblage (LG) of Devono-Mississippian augen gneiss, quartz-mica schist, quartzite, and amphibolite; the Taylor Mountain assemblage (TM) of mafic schist and gneiss, marble, quartzite, and metachert; and the Seventymile terrane of greenstone, serpentinized peridotite, and Mississippian to Late Triassic metasedimentary rocks. Most LG amphibolites have relatively high Nb, TiO2, Zr, and light rare earth element contents, indicative of an alkalic to tholeiitic, within-plate basalt origin. The within-plate affinities of the LG amphibolites suggest that their basaltic parent magmas developed in an extensional setting and support a correlation of these metamorphosed continental-margin rocks with less metamorphosed counterparts across the Tintina fault in the Selwyn Basin of the Canadian Cordillera. TM amphibolites have a tholeiitic or calc-alkalic composition, low normalized abundances of Nb and Ta relative to Th and La, and Ti/V values of <20, all indicative of a volcanic-arc origin. Limited results from Seventymile greenstones indicate a tholeiitic or calc-alkalic composition and intermediate to high Ti/V values (27-48), consistent with either a within-plate or an ocean-floor basalt origin. Y-La-Nb proportions in both TM and Seventymile metabasalts indicate the proximity of the arc and marginal basin to continental crust. The arc geochemistry of TM amphibolites is consistent with a model in which the TM assemblage includes arc rocks generated above a west-dipping subduction zone outboard of the North American continental margin in mid-Paleozoic through Triassic time. The ocean-floor or within-plate basalt geochemistry of the Seventymile greenstones supports the correlation of the Seventymile terrane with the Slide Mountain terrane in Canada and the hypothesis that these oceanic

  11. Relations between continuous real-time turbidity data and discrete suspended-sediment concentration samples in the Neosho and Cottonwood Rivers, east-central Kansas, 2009-2012

    USGS Publications Warehouse

    Foster, Guy M.

    2014-01-01

    The Neosho River and its primary tributary, the Cottonwood River, are the primary sources of inflow to the John Redmond Reservoir in east-central Kansas. Sedimentation rate in the John Redmond Reservoir was estimated as 743 acre-feet per year for 1964–2006. This estimated sedimentation rate is more than 80 percent larger than the projected design sedimentation rate of 404 acre-feet per year, and resulted in a loss of 40 percent of the conservation pool since its construction in 1964. To reduce sediment input into the reservoir, the Kansas Water Office implemented stream bank stabilization techniques along an 8.3 mile reach of the Neosho River during 2010 through 2011. The U.S. Geological Survey, in cooperation with the Kansas Water Office and funded in part through the Kansas State Water Plan Fund, operated continuous real-time water-quality monitors upstream and downstream from stream bank stabilization efforts before, during, and after construction. Continuously measured water-quality properties include streamflow, specific conductance, water temperature, and turbidity. Discrete sediment samples were collected from June 2009 through September 2012 and analyzed for suspended-sediment concentration (SSC), percentage of sediments less than 63 micrometers (sand-fine break), and loss of material on ignition (analogous to amount of organic matter). Regression models were developed to establish relations between discretely measured SSC samples, and turbidity or streamflow to estimate continuously SSC. Continuous water-quality monitors represented between 96 and 99 percent of the cross-sectional variability for turbidity, and had slopes between 0.91 and 0.98. Because consistent bias was not observed, values from continuous water-quality monitors were considered representative of stream conditions. On average, turbidity-based SSC models explained 96 percent of the variance in SSC. Streamflow-based regressions explained 53 to 60 percent of the variance. Mean squared

  12. The early Cretaceous orogen-scale Dabieshan metamorphic core complex: implications for extensional collapse of the Triassic HP-UHP orogenic belt in east-central China

    NASA Astrophysics Data System (ADS)

    Ji, Wenbin; Lin, Wei; Faure, Michel; Shi, Yonghong; Wang, Qingchen

    2016-03-01

    The Dabieshan massif is famous as a portion of the world's largest HP-UHP metamorphic belt in east-central China that was built by the Triassic North-South China collision. The central domain of the Dabieshan massif is occupied by a huge migmatite-cored dome [i.e., the central Dabieshan dome (CDD)]. Origin of this domal structure remains controversial. Synthesizing previous and our new structural and geochronological data, we define the Cretaceous Dabieshan as an orogen-scale metamorphic core complex (MCC) with a multistage history. Onset of lithospheric extension in the Dabieshan area occurred as early as the commencement of crustal anatexis at the earliest Cretaceous (ca. 145 Ma), which was followed by primary (early-stage) detachment during 142-130 Ma. The central Dabieshan complex in the footwall and surrounding detachment faults recorded a consistently top-to-the-NW shearing. It is thus inferred that the primary detachment was initiated from a flat-lying detachment zone at the middle crust level. Removal of the orogenic root by delamination at ca. 130 Ma came into the extensional climax, and subsequently isostatic rebound resulted in rapid doming. Along with exhumation of the footwall, the mid-crustal detachment zone had been warped as shear zones around the CDD. After 120 Ma, the detachment system probably experienced a migration accommodated to the crustal adjustment, which led to secondary (late-stage) detachment with localized ductile shearing at ca. 110 Ma. The migmatite-gneiss with HP/UHP relicts in the CDD (i.e., the central Dabieshan complex) was product of the Cretaceous crustal anatexis that consumed the deep-seated part of the HP-UHP slices and the underlying para-autochthonous basement. Compared with the contemporaneous MCCs widely developed along the eastern margin of the Eurasian continent, we proposed that occurrence of the Dabieshan MCC shares the same tectonic setting as the "destruction of the North China craton". However, geodynamic trigger

  13. Geological and isotopic evidence for magmatic-hydrothermal origin of the Ag-Pb-Zn deposits in the Lengshuikeng District, east-central China

    NASA Astrophysics Data System (ADS)

    Wang, Changming; Zhang, Da; Wu, Ganguo; Santosh, M.; Zhang, Jing; Xu, Yigan; Zhang, Yaoyao

    2014-08-01

    The Lengshuikeng ore district in east-central China has an ore reserve of ˜43 Mt with an average grade of 204.53 g/t Ag and 4.63 % Pb + Zn. Based on contrasting geological characteristics, the mineralization in the Lengshuikeng ore district can be divided into porphyry-hosted and stratabound types. The porphyry-hosted mineralization is distributed in and around the Lengshuikeng granite porphyry and shows a distinct alteration zoning including minor chloritization and sericitization in the proximal zone; sericitization, silicification, and carbonatization in the peripheral zone; and sericitization and carbonatization in the distal zone. The stratabound mineralization occurs in volcano-sedimentary rocks at ˜100-400 m depth without obvious zoning of alterations and ore minerals. Porphyry-hosted and stratabound mineralization are both characterized by early-stage pyrite-chalcopyrite-sphalerite, middle-stage acanthite-native silver-galena-sphalerite, and late-stage pyrite-quartz-calcite. The δ34S values of pyrite, sphalerite, and galena in the ores range from -3.8 to +6.9‰ with an average of +2.0‰. The C-O isotope values of siderite, calcite, and dolomite range from -7.2 to -1.5‰ with an average of -4.4‰ (V-PDB) and from +10.9 to +19.5‰ with an average of +14.8‰ (V-SMOW), respectively. Hydrogen, oxygen, and carbon isotopes indicate that the hydrothermal fluids were derived mainly from meteoric water, with addition of minor amounts of magmatic water. Geochronology employing LA-ICP-MS analyses of zircons from a quartz syenite porphyry yielded a weighted mean 206Pb/238U age of 136.3 ± 0.8 Ma considered as the emplacement age of the porphyry. Rb-Sr dating of sphalerite from the main ore stage yielded an age of 126.9 ± 7.1 Ma, marking the time of mineralization. The Lengshuikeng mineralization classifies as an epithermal Ag-Pb-Zn deposit.

  14. Characteristics of GLAS and Small Footprint Airborne Lidar Waveform Data from East- Central Mississippi Pine/Hardwood Forest and Central Texas Oak/Juniper Savanna

    NASA Astrophysics Data System (ADS)

    Gutierrez, R.; Neuenschwander, A. L.; Urban, T. J.; Schutz, B. E.; Evans, D. L.

    2006-12-01

    The accurate measurement of topography and vegetation structure is a vital component of any geomorphic and ecological characterization of the earth's surface. The Geoscience Laser Altimeter System (GLAS) on-board the Ice, Cloud and land Elevation Satellite (ICESat) is producing an unprecedented, near-global dataset of lidar waveforms resulting in range measurements with a precision of approximately 3 cm for non-vegetated surface. However, challenges remain regarding the accuracy of GLAS elevations over vegetated terrain. Data from three ICESat ascending passes were acquired over the Freeman Ranch, located near San Marcos, Texas on 14 March 2005, 26 October 2005 and again on 26 February 2006 to investigate the use of waveform lidar for determining vegetation structure. In addition, two ICESat ascending passes were acquired over forested portions of Oktibbeha County in east-central Mississippi on 3 March 2006 and 11 March 2006. The Freeman Ranch is characterized by a mixture of rangeland and Oak-Juniper woodlands, and is the focus of several studies on savanna ecosystem carbon storage. The Oktibbeha County survey area includes the John W. Starr Memorial Forest, a research forest composed of upland pine and pine/hardwood forest, bottomland hardwood forest and pine plantation. Topography at both Freeman Ranch and Oktibbeha County is flat to gently-rolling hills dissected by small streams. To validate the potential of GLAS waveforms for determining vegetation structure and assess the accuracy of GLAS topographic measurements, small-footprint airborne lidar data were collected over Freeman Ranch on 12 August 2005 using an Optech ALTM 1225 system. Airborne lidar data were also collected along the ICESAT ground tracks over Oktibbeha County on 26-27 July, 2006. The UT ALTM system is equipped with a waveform digitizer that allows the simultaneous recording of conventional first and last return lidar data and the corresponding reflection waveforms at the 25 kHz laser pulse

  15. Examples of Holocene and latest Pleistocene faulting in northern and eastern Nevada

    SciTech Connect

    Ramelli, A.R.; Depolo, C.M. )

    1993-04-01

    Although it is generally accepted that tectonic activity in the Basin and Range province (BRP) is highest along the region's eastern and western margins, significant Holocene and latest Pleistocene activity has occurred in the central BRP as well, including northern and eastern Nevada. Some such faults are depicted in the few existing active fault compilations, but detailed studies are generally lacking and the actual levels of activity are often misrepresented. Examples of Holocene or latest Pleistocene faulting in northern and eastern Nevada include the Black Rock, Tuscarora, Thousand Springs Valley, and Railroad Valley fault zones. The Black Rock ault zone has hosted two or more Holocene events, including an event within the past 1.1 ka and resulting in a prominent fault scarp about 2.2 m high crossing the playa floor of the Black Rock Desert. The Tuscarora fault zone cuts an alluvial/pediment surface in southwestern Independence Valley, north-central Nevada, forming a complex graben at least 15 km long and 3.5 km wide, and has probable late Holocene activity. Single- and multiple-event scarps along the Thousand Springs Valley fault zone in northeastern Nevada suggest a 2 m Holocene/latest Pleistocene event and a minimum 17 m displacement of an early- to mid-Quaternary surface. Fault scarp profiles from the Railroad Valley fault zone in east-central Nevada, which has an overall length of about 120 km suggest an early Holocene or latest Pleistocene event, single event displacements of 1.5 to 2.5 m, and a late Quaternary slip rate of 0.1 to 0.2 mm/yr.

  16. Analyses of Water-Level Differentials and Variations in Recharge between the Surficial and Upper Floridan Aquifers in East-Central and Northeast Florida

    USGS Publications Warehouse

    Murray, Louis C., Jr.

    2007-01-01

    Continuous (daily) water-level data collected at 29 monitoring-well cluster sites were analyzed to document variations in recharge between the surficial (SAS) and Floridan (FAS) aquifer systems in east-central and northeast Florida. According to Darcy's law, changes in the water-level differentials (differentials) between these systems are proportional to changes in the vertical flux of water between them. Variations in FAS recharge rates are of interest to water-resource managers because changes in these rates affect sensitive water resources subject to minimum flow and water-level restrictions, such as the amount of water discharged from springs and changes in lake and wetland water levels. Mean daily differentials between 2000-2004 ranged from less than 1 foot at a site in east-central Florida to more than 114 feet at a site in northeast Florida. Sites with greater mean differentials exhibited lower percentage-based ranges in fluctuations than did sites with lower mean differentials. When averaged for all sites, differentials (and thus Upper Floridan aquifer (UFA) recharge rates) decreased by about 18 percent per site between 2000-2004. This pattern can be associated with reductions in ground-water withdrawals from the UFA that occurred after 2000 as the peninsula emerged from a 3-year drought. Monthly differentials exhibited a well-defined seasonal pattern in which UFA recharge rates were greatest during the dry spring months (8 percent above the 5-year daily mean in May) and least during the wetter summer/early fall months (4 percent below the 5-year daily mean in October). In contrast, differentials exceeded the 5-year daily mean in all but 2 months of 2000, indicative of relatively high ground-water withdrawals throughout the year. On average, the UFA received about 6 percent more recharge at the project sites in 2000 than between 2000-2004. No statistically significant correlations were detected between monthly differentials and precipitation at 27 of the

  17. Special Nevada report

    SciTech Connect

    1991-09-23

    This report is submitted to Congress by the Secretary of the Air Force, the Secretary of the Navy, and the Secretary of the Interior pursuant to Section 6 of the Military Lands Withdrawal Act of 1986. It contains an analysis and evaluation of the effects on public health and safety resulting from DOD and Department of Energy (DOE) military and defense-related uses on withdrawn public lands in the State of Nevada and in airspace overlying the State. This report describes the cumulative impacts of those activities on public and private property in Nevada and on plants, fish and wildlife, cultural, historic, scientific, recreational, wilderness and other resources of the public lands of Nevada. An analysis and evaluation of possible measures to mitigate the cumulative effects of the withdrawal of lands and the use of airspace in Nevada for defense-related purposes was conducted, and those considered practical are listed.

  18. NEVADA INDIAN RESERVATIONS

    EPA Science Inventory

    Polygon coverage of all Indian Reservations in Nevada. Reservation boundaries are compiled from multiple sources and are derived from several different source scales. Information such as reservation type, primary tribe name and location source are included with the coverage. As...

  19. SUGARLOAF ROADLESS AREA, NEVADA.

    USGS Publications Warehouse

    McKee, Edwin H.; Schmauch, Steven W.

    1984-01-01

    On the basis of a mineral survey local areas in and near the western edge of the Sugarloaf Roadless Area, Nevada have probable resource potential for silver and small amounts of associated lead, zinc, and gold.

  20. Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas

    USGS Publications Warehouse

    Warwick, P.D.; Crowley, S.S.; Ruppert, L.F.; Pontolillo, J.

    1997-01-01

    This study examined the petrographic and geochemical characteristics of two lignite beds (3500 and 4500 beds, Manning Formation, Jackson Group, Eocene) that are mined at the Gibbons Creek mine in east-central Texas. The purpose of the study was to identify the relations among sample ash yield, coal petrography, and trace-element concentrations in lignite and adjoining rock layers of the Gibbons Creek mine. Particular interest was given to the distribution of 12 environmentally sensitive trace elements (As, Be, Cd, Cr, Co, Hg, Mn, Ni, Pb, Sb, Se, and U) that have been identified as potentially hazardous air pollutants (HAPs) in the United States Clean Air Act Amendments of 1990. Eleven lignite, floor, and rock parting samples were collected from incremental channel samples of the 3500 and 4500 beds that were exposed in a highwall of pit A3 at the Gibbons Creek mine. Short proximate and ultimate and forms of sulfur analyses were performed on all lignite samples, and lignite and rock samples were analyzed for 60 major, minor and trace elements. Representative splits of all lignite samples were ground and cast into pellets, and polished for petrographic analyses in blue-light fluorescence and reflected white light to determine liptinite, inertinite, and huminite maceral group percentages. The following observations summarize our results and conclusions about the geochemistry, petrography, and sedimentology of the 3500 and 4500 beds of the Gibbons Creek lignite deposit: (1) Weighted average dry (db) ash yield for the two beds is 29.7%, average total sulfur content is 2.6%, and average calorific value is 7832 Btu (18.22 MJ/kg). Ash yields are greatest in the lower bench (59.33% db) of the 3500 bed and in the upper bench of the 4500 bed (74.61% db). (2) For lignite samples (on a whole-coal basis), the distributions of two of the HAPs (Pb and Sb) are positively related to ash yield, probably indicating an inorganic affinity for these elements. By using cluster analysis we

  1. 40Ar 39Ar age constraints on neogene sedimentary beds, Upper Ramparts, half-way Pillar and Canyon village sites, Porcupine river, east-central Alaska

    USGS Publications Warehouse

    Kunk, M.J.; Rieck, H.; Fouch, T.D.; Carter, L.D.

    1994-01-01

    40Ar 39Ar ages of volcanic rocks are used to provide numerical constraints on the age of middle and upper Miocene sedimentary strata collected along the Porcupine River. Intercalated sedimentary rocks north of latitude 67??10???N in the Porcupine terrane of east-central Alaska contain a rich record of plant fossils. The fossils are valuable indicators of this interior region's paleoclimate during the time of their deposition. Integration of the 40Ar 39Ar results with paleomagnetic and sedimentological data allows for refinements in estimating the timing of deposition and duration of selected sedimentary intervals. 40Ar 39Ar plateau age spectra, from whole rock basalt samples, collected along the Upper Ramparts and near Half-way Pillar on the Porcupine River, range from 15.7 ?? 0.1 Ma at site 90-6 to 14.4 ?? 0.1 Ma at site 90-2. With exception of the youngest basalt flow at site 90-2, all of the samples are of reversed magnetic polarity, and all 40Ar 39Ar age spectrum results are consistent with the deposition of the entire stratigraphic section during a single interval of reversed magnetic polarity. The youngest flow at site 90-2 was emplaced during an interval of normal polarity. With age, paleomagnetic and sedimentological data, the ages of the Middle Miocene sedimentary rocks between the basalt flows at sites 90-1 and 90-2 can be assigned to an interval within the limits of analytical precision of 15.2 ?? 0.1 Ma; thus, the sediments were deposited during the peak of the Middle Miocene thermal maximum. Sediments in the upper parts of sites 90-1 and 90-2 were probably deposited during cooling from the Middle Miocene thermal maximum. 40Ar 39Ar results of plagioclase and biotite from a single tephra, collected at sites 90-7 and 90-8 along the Canyon Village section of the Porcupine River, indicate an age of 6.57 ?? 0.02 Ma for its time of eruption and deposition. These results, together with sedimentological and paleomagnetic data, suggest that all of the Upper

  2. The Paleozoic Ozbak-Kuh carbonate-hosted Pb-Zn deposit of East Central Iran: Isotope (C, O, S, Pb) geochemistry and ore genesis

    NASA Astrophysics Data System (ADS)

    Ehya, Farhad

    2014-02-01

    Lead and zinc mineralization occurs in dolostones of the Middle Devonian Sibzar Formation at Ozbak-Kuh, which is located 150 km north of Tabas city in East Central Iran. The ore is composed of galena, sphalerite and calcite, with subordinate dolomite and bitumen. Wall-rock alterations include carbonate recrystallization and dolomitization. Microscopic studies reveal that the host rock is replaced by galena and sphalerite. The Pb-Zn mineralization is epigenetic and stratabound. The δ13C values of hydrothermal calcite samples fall in the narrow range between -0.3‰ and 0.8‰. The δ18O values in calcite display a wider range, between -14.5‰ and -11.9‰. The δ13C and δ18O values overlap with the oxygen and carbon isotopic compositions of Paleozoic seawater, indicating the possible important participation of Paleozoic seawater in the ore-forming fluid. The δ18O signature corresponds to a spread in temperature of about 70 °C in the ore-bearing fluid. The δ13C values indicate that the organic materials within the host rocks did not contribute significantly in the hydrothermal fluid. The δ34S values of galena and sphalerite samples occupy the ranges of 12.2‰-16.0‰ and 12.1-16.8‰, respectively. These values reveal that the seawater sulfate is the most probable source of sulfur. The reduced sulfur was most likely supplied through thermochemical sulfate reduction. The sulfur isotope ratios of co-precipitated sphalerite-galena pairs suggest that deposition of the sulfide minerals took place under chemical disequilibrium conditions. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of the galena samples represent average values of 18.08, 15.66, and 38.50, respectively. These ratios indicate that galena Pb likely originated from an orogenic source in which supracrustal rocks with high 238U/204Pb and 232Th/204Pb ratios are dominant. The average lead isotope model age portrays Cambrian age. This model age is not coeval with the host rocks, which are of middle

  3. Dating slate belts using 40Ar/39Ar geochronology and zircon ages from crosscutting plutons: A case study from east-central Maine, USA

    NASA Astrophysics Data System (ADS)

    Ghanem, Hind; Kunk, Michael; Ludman, Allan; Bish, David; Wintsch, Robert

    2016-04-01

    Determining the tectonic significance of slate belts is a persistent problem in many orogenic belts because of the lack of time constraints on the age of deposition and the age(s) of cleavages. We have solved this problem in east-central Maine where the ages of the regional Acadian cleavage (S1) and local ductile fault zone cleavage (S2) were both constrained using 40Ar/39Ar geochronology and the ages of crosscutting plutons. Applying 40Ar/39Ar geochronology to rocks with multiple generations of muscovite was possible because each cleavage-forming muscovite records a crystallization age rather than a cooling age due to the low grade of regional metamorphism. Evidence for metamorphic crystallization in rocks dominated by regional Acadian cleavage (S1) comes from the truncations of detrital and authigenic muscovite and chlorite grains by new muscovite and chlorite grains that define the S1 foliation. In rocks that display two foliations, the evidence comes from the truncations of chlorite and muscovite grains defining all earlier fabrics by new muscovite grains in the younger folia (S2). Step-heating experiments using the 40Ar/39Ar technique on twelve samples all yielded sigmoidal age spectra. The low-temperature steps produced a hump in the age spectra, indicating 39Ar recoil into adjacent interlayered chlorite grains, the latter interlayering confirmed by back-scattered electron imaging. Continuing steps climbed steadily from those with minimum apparent ages as young as ~381 Ma to steps with maximum ages as old as 466 Ma. The samples with the lowest minimum apparent age steps are those in which the S2 cleavage-forming mica population dominates. In contrast, the oldest apparent age steps are from samples that have the highest modal abundance of detrital micas. The Middle Ordovician age of the maximum age steps is interpreted to be the minimum cooling age of the detrital micas. The minimum 40Ar/39Ar age steps of muscovite in the samples that display only S1 cleavage

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

    PubMed Central

    Li, Qiang; Wang, Xiaoming

    2015-01-01

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

  5. Central Nevada Test Area, Nevada Fact Sheet

    SciTech Connect

    2009-04-01

    The Central Nevada Test Area (CNTA) is in the Hot Creek Valley of south-central Nevada, approximately 70 miles northeast of Tonopah. The CNTA consists of three parcels totaling 2,560 acres. The parcels are spaced approximately 3 miles apart along a roughly north-south line. The total acreage is currently withdrawn from all forms of appropriation associated with mining laws and leasing. The U.S. Atomic Energy Commission, a predecessor agency of the U.S. Department of Energy (DOE), acquired the CNTA in the early 1960s to develop alternative sites to the Nevada National Security Site (formerly known as the Nevada Test Site) for underground nuclear testing. Three emplacement boreholes (UC-1, UC-3, and UC-4) were drilled on the three parcels at the CNTA for underground nuclear testing. The initial underground nuclear test at CNTA, Faultless, was conducted in borehole UC-1 at a depth of 3,199 feet below ground surface on January 19, 1968. The yield of the Faultless test was estimated to be 0.2 to 1 megaton. Its purpose was to evaluate the environmental and structural effects that might be expected if subsequent, higher-yield underground nuclear tests were conducted in this vicinity. The test resulted in a down-dropped fault block visible at land surface. In addition, seismic results supported the indication that the site was not favorable for larger detonations. The nuclear detonation created a cavity with a radius of approximately 328 feet. The Faultless test did not release any radioactivity at the surface, and no additional tests were conducted at the CNTA.

  6. Trace metal distribution in pristine permafrost-affected soils of the Lena River Delta and its Hinterland, Northern Siberia, Russia

    NASA Astrophysics Data System (ADS)

    Antcibor, I.; Zubrzycki, S.; Eschenbach, A.; Kutzbach, L.; Bol'shiyanov, D.; Pfeiffer, E.-M.

    2013-02-01

    Soils are an important compartment of ecosystems and have the ability to immobilize chemicals preventing their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since the Arctic ecosystems are considered to be very sensitive to climatic changes as well as to chemical contamination. This study characterizes background levels of trace metals in permafrost-affected soils of the Lena River Delta and its hinterland in northern Siberia (73.5° N-69.5° N) representing a remote region far from evident anthropogenic trace metal sources. Investigations on total element contents of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co) and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest concentrations of the majority of the measured elements were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) in the Lena River Delta region. Correlation analyses of trace metal concentrations and soil chemical and physical properties at a Holocene estuarine terrace and two modern floodplain levels in the southern-central Lena River Delta (Samoylov Island) showed that the main factors controlling the trace metal distribution in these soils are organic matter content, soil texture and contents of iron and manganese-oxides. Principal Component Analysis (PCA) revealed that soil oxides play a significant role in trace metal distribution in both top and bottom horizons. Occurrence of organic matter contributes to Cd binding in top soils and Cu binding in bottom horizons. Observed ranges of the background concentrations of the majority of trace elements were similar to

  7. New Constraints on the Geometry and Kinematics of Active Faults in the Hinterland of the Northwest Himalaya

    NASA Astrophysics Data System (ADS)

    Morell, K. D.; Sandiford, M.; Rajendran, C. C. P.; Fink, D.; Kohn, B. P.

    2014-12-01

    The geometry and kinematics of the active, and potentially seismogenic, fault structures within the hinterland of the Himalaya have proven challenging to constrain in the past, primarily because active faults in this region tend to be buried beneath the subsurface and active seismicity often does not align with surficially mapped fault traces. Here we present a series of complementary datasets, including results from low temperature thermochronology, basin-wide erosion rates from 10Be concentrations, and topographic and longitudinal profile analyses, that place constraints on the spatial distribution of fault-related rock uplift and erosion across a ~400-km long region of the lower and high Himalaya of northwest India. Results from our analyses reveal that hillslope morphology and channel steepness are relatively invariant parallel to strike but vary significantly across strike, with the most prominent and abrupt variations occurring at the physiographic transition between the lower and high Himalaya (PT2), near the axial trace of the ramp-flat transition in the Main Himalayan Thrust (MHT). The cross-strike changes in geomorphology observed across the PT2 correlate with an order of magnitude northward increase in basin-wide erosion rates (~0.06-0.8 mm/a) and a corresponding decrease in apatite (~5-2 Ma) and zircon (U-Th)/He (~10-2 Ma) cooling ages. Combined with published geophysical and seismicity data, we interpret these results to reflect spatial variations in rock uplift and exhumation induced by a segment of the MHT ramp-flat system that is at least ~400 km long and ~125 km wide. The relatively young (U-Th)/He ages (<10 Ma) greater than 20 km south of the MHT ramp-flat transition preliminarily suggest that the kinematics of this system are best explained by a model which incorporates an accreting duplex on the MHT ramp but additional forthcoming analyses, including thermal modeling, will confirm if this hypothesis is robust.

  8. Oligocene-Miocene deformational and depositional history of the Andean hinterland basin in the northern Altiplano plateau, southern Peru

    NASA Astrophysics Data System (ADS)

    Perez, Nicholas D.; Horton, Brian K.

    2014-09-01

    Cenozoic basin fill of the northern Altiplano plateau records the tectonic development of the flanking Western Cordillera magmatic arc and Eastern Cordillera fold-thrust belt. The Ayaviri hinterland basin of southern Peru contains a ~2300 m thick succession of fluvial sandstones and overbank siltstones (upper Oligocene Puno Group and lower Miocene lower Tinajani Formation) capped by ~400 m of alluvial fan conglomerates (middle Miocene upper Tinajani Formation). New U-Pb zircon chronostratigraphic constraints from ~30 to 15 Ma yield sediment accumulation rates of 110-660 m/Myr. Newly dated growth strata highlight the genetic role played by thrust displacement in basin evolution. A several phase accumulation history derived from chronostratigraphic, provenance, and structural data reveals Oligocene basin filling by fluvial sand and mud that changes provenance from Western Cordillera Mesozoic-Cenozoic volcanic rocks to Paleozoic-Mesozoic Eastern Cordillera sedimentary rocks driven by deformation along the southwest directed, northeastern basin margin Ayaviri thrust at 28-26 Ma. Continued early Miocene fluvial deposition was sourced solely from the Eastern Cordillera. An abrupt middle Miocene shift to coarse alluvial fan deposition sourced from the Western Cordillera was driven by out-of-sequence deformation along the northeast directed, southwestern basin margin Pasani thrust at 18-16 Ma. This northern Altiplano out-of-sequence deformation was coincident with increased Eastern and Western Cordillera exhumation and thrusting and may be symptomatic of changes in critical wedge dynamics. The overall record of basin sedimentation and syndepositional fold-thrust deformation emphasizes the role of regional shortening in governing crustal thickening and basin evolution in the central Andes during the Oligocene to Miocene.

  9. KNOW YOUR NEVADA INDIANS.

    ERIC Educational Resources Information Center

    POEHLMAN, CHARLES H.; AND OTHERS

    THIS PUBLICATION PRESENTS THE RESULTS OF A STUDY OF THE SOCIOCULTURAL BACKGROUNDS OF THE PAIUTE, WASHOE, AND SHOSHONE INDIANS OF NEVADA. INCLUDED ARE AN OUTLINE OF GENERAL PROBLEMS PERTAINING TO INDIAN EDUCATION, SOME DISTINCT CULTURAL DIFFERENCES BETWEEN THE DOMINANT NON-INDIAN SOCIETY AND THE INDIAN SOCIETY, AND THE PREHISTORIC ASPECTS OF THE…

  10. University of Nevada, Reno

    ERIC Educational Resources Information Center

    Library Journal, 2004

    2004-01-01

    A $10 million gift will help the University of Nevada, Reno (UNR), begin construction next year on a new $66 million "Knowledge Center." The donation comes in $5 million gifts from Reno-based International Game Technology (IGT), a slot machine manufacturer, and from former IGT chair Chuck Mathewson and his wife, Ann. UNR's current library was…