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Sample records for basin western north

  1. Depositional sequences in a foreland basin (north-western domain of the continental Duero basin, Spain)

    Science.gov (United States)

    Herrero, Antonio; Alonso-Gavilán, Gaspar; Colmenero, Juan Ramón

    2010-01-01

    The Cenozoic record of the north-western domain of the Duero basin is articulated at the surface through a set of continental depositional sequences called, from base to top, the Vegaquemada sequence, the Candanedo sequence, and the Barrillos sequence. These depositional sequences were deposited in continental sedimentary environments. The deposition of the first sequence occurred through a fluvial system with floodplains cut by low-sinuosity channels. The Vegaquemada sequence was developed between the Middle Eocene and the Early Agenian. The second sequence was formed by a set of highly efficient transport alluvial fans that evolved laterally towards fluvial systems with low-sinuosity fluvial channels and an extensive floodplain, where several types of palaeosols were formed. This sequence developed between the Early Agenian and the Late Vallesian. The third unit-the Barrillos sequence (between the Late Vallesian and the Turolian/Ruscinian transition), was generated by a set of highly efficient transport alluvial fans dominated by low-sinuosity fluvial channels. In subsurface geology, seismic and well data are used to rebuild the stratigraphic architecture. The two basal depositional sequences can be identified with two seismic units: the Palaeogene Seismic Unit (PgSU) and the Neogene Seismic Unit (NgSU), respectively. In the present work, we obtained the isovelocity, isochron, and isobath maps for the top and base of the two Cenozoic units. The Palaeozoic (PzSU) and Mesozoic (MzSU) seismic units are found under these two units. Through study of the logs of the various boreholes, it was only possible to analyse the upper 700 m of the Candanedo Sequence (NgSU), without encompassing the total thickness of the unit. Several middle-order sequences were differentiated, in general showing a sequential fining-upwards evolutionary character. Additionally, for the boreholes analysed two main types of electrofacies were identified, both representing fluvial channels and

  2. Seasonality of Groundwater Recharge in the Basin and Range Province, Western North America

    Science.gov (United States)

    Neff, K. L.; Meixner, T.; Ajami, H.; De La Cruz, L.

    2015-12-01

    For water-scarce communities in the western U.S., it is critical to understand groundwater recharge regimes and how those regimes might shift in the face of climate change and impact groundwater resources. Watersheds in the Basin and Range Geological Province are characterized by a variable precipitation regime of wet winters and variable summer precipitation. The relative contributions to groundwater recharge by summer and winter precipitation vary throughout the province, with winter precipitation recharge dominant in the northern parts of the region, and recharge from summer monsoonal precipitation playing a more significant role in the south, where the North American Monsoon (NAM) extends its influence. Stable water isotope data of groundwater and seasonal precipitation from sites in Sonora, Mexico and the U.S. states of California, Nevada, Utah, Arizona, Colorado, New Mexico, and Texas were examined to estimate and compare groundwater recharge seasonality throughout the region. Contributions of winter precipitation to annual recharge vary from 69% ± 41% in the southernmost Río San Miguel Basin in Sonora, Mexico, to 100% ± 36% in the westernmost Mojave Desert of California. The Normalized Seasonal Wetness Index (NSWI), a simple water budget method for estimating recharge seasonality from climatic data, was shown to approximate recharge seasonality well in several winter precipitation-dominated systems, but less well in basins with significant summer precipitation.

  3. Lava and Life: New investigations into the Carson Volcanics, lower Kimberley Basin, north Western Australia

    Science.gov (United States)

    Orth, Karin; Phillips, Chris; Hollis, Julie

    2014-05-01

    The Carson Volcanics are the only volcanic unit in the Paleoproterozoic Kimberley Basin and are part of a poorly studied Large Igneous Province (LIP) that was active at 1790 Ma. New work focussing on this LIP in 2012 and 2013 involved helicopter-supported traverses and sampling of the Carson Volcanics in remote areas near Kalumburu in far north Western Australia's Kimberley region. The succession is widespread and flat lying to gently dipping. It consists of three to six basalt units with intercalated sandstone and siltstone. The basalts are 20-40 m thick, but can be traced up to 60 km along strike. The basalt can be massive or amygdaloidal and commonly display polygonal to subhorizontal and rare vertical columnar jointing. Features of the basalt include ropy lava tops and basal pipe vesicles consistent with pahoehoe lavas. The intercalated cross-bedded quartzofeldspathic sandstone and siltstone vary in thickness up to 40 m and can be traced up to 40 km along strike. Peperite is common and indicates interaction between wet, unconsolidated sediment and hot lava. Stromatolitic chert at the top of the formation represents the oldest life found within the Kimberley region. Mud cracks evident in the sedimentary rocks, and stromatolites suggest an emergent broad tidal flat environment. The volcanics were extruded onto a wide marginal margin setting subject to frequent flooding events. Thickening of the volcanic succession south and the palaeocurrents in the underlying King Leopold Sandstone and the overlying Warton Sandstone suggest that this shelf sloped to the south. The type of basalt and the basalt morphology indicate a low slope gradient of about 1°.

  4. Freshwater fish faunas, habitats and conservation challenges in the Caribbean river basins of north-western South America.

    Science.gov (United States)

    Jiménez-Segura, L F; Galvis-Vergara, G; Cala-Cala, P; García-Alzate, C A; López-Casas, S; Ríos-Pulgarín, M I; Arango, G A; Mancera-Rodríguez, N J; Gutiérrez-Bonilla, F; Álvarez-León, R

    2016-07-01

    The remarkable fish diversity in the Caribbean rivers of north-western South America evolved under the influences of the dramatic environmental changes of neogene northern South America, including the Quechua Orogeny and Pleistocene climate oscillations. Although this region is not the richest in South America, endemism is very high. Fish assemblage structure is unique to each of the four aquatic systems identified (rivers, streams, floodplain lakes and reservoirs) and community dynamics are highly synchronized with the mono-modal or bi-modal flooding pulse of the rainy seasons. The highly seasonal multispecies fishery is based on migratory species. Freshwater fish conservation is a challenge for Colombian environmental institutions because the Caribbean trans-Andean basins are the focus of the economic development of Colombian society, so management measures must be directed to protect aquatic habitat and their connectivity. These two management strategies are the only way for helping fish species conservation and sustainable fisheries. PMID:27401480

  5. A new troodontid theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America.

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    Lindsay E Zanno

    Full Text Available BACKGROUND: Troodontids are a predominantly small-bodied group of feathered theropod dinosaurs notable for their close evolutionary relationship with Avialae. Despite a diverse Asian representation with remarkable growth in recent years, the North American record of the clade remains poor, with only one controversial species--Troodon formosus--presently known from substantial skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a gracile new troodontid theropod--Talos sampsoni gen. et sp. nov.--from the Upper Cretaceous Kaiparowits Formation, Utah, USA, representing one of the most complete troodontid skeletons described from North America to date. Histological assessment of the holotype specimen indicates that the adult body size of Talos was notably smaller than that of the contemporary genus Troodon. Phylogenetic analysis recovers Talos as a member of a derived, latest Cretaceous subclade, minimally containing Troodon, Saurornithoides, and Zanabazar. MicroCT scans reveal extreme pathological remodeling on pedal phalanx II-1 of the holotype specimen likely resulting from physical trauma and subsequent infectious processes. CONCLUSION/SIGNIFICANCE: Talos sampsoni adds to the singularity of the Kaiparowits Formation dinosaur fauna, which is represented by at least 10 previously unrecognized species including the recently named ceratopsids Utahceratops and Kosmoceratops, the hadrosaurine Gryposaurus monumentensis, the tyrannosaurid Teratophoneus, and the oviraptorosaurian Hagryphus. The presence of a distinct troodontid taxon in the Kaiparowits Formation supports the hypothesis that late Campanian dinosaurs of the Western Interior Basin exhibited restricted geographic ranges and suggests that the taxonomic diversity of Late Cretaceous troodontids from North America is currently underestimated. An apparent traumatic injury to the foot of Talos with evidence of subsequent healing sheds new light on the paleobiology of deinonychosaurians

  6. Deep phylogeographic divisions and long-term persistence of forest invertebrates (Hexapoda: Collembola) in the North-Western Mediterranean basin.

    Science.gov (United States)

    Cicconardi, F; Nardi, F; Emerson, B C; Frati, F; Fanciulli, P P

    2010-01-01

    The North-Western Mediterranean basin is well known for its high number of relictual endemic taxa, and has been indicated as one of the world's major biodiversity hotspots at the species level. A possible contributing factor may be long-term persistence of populations and their prolonged stability. This study was designed to investigate the phylogeographic structure of three common species of the genus Lepidocyrtus (Hexapoda: Collembola), soil-dwelling arthropods characterized by limited dispersal capabilities and generally associated with forest habitats. We observed a remarkable geographic structure, with numerous deeply divergent genetic lineages occupying islands as well as mainland sites with no apparent gene flow among most sites, even across distances of only tens of kilometres. The reconstructed time frame for the evolution of these lineages suggests divergence between 5 and 15 Ma. This indicates a remarkably ancient origin and long-term persistence of individual lineages over a fine geographic scale despite the occurrence of abrupt sea level and climatic fluctuations in the area. This further suggests that currently recognized morphological species might be a serious underestimation of the true springtail biodiversity within this region. PMID:20015142

  7. Prospect evaluation of BED 3 and Sitra oilfields, Abu Gharadig Basin, North Western Desert, Egypt

    Science.gov (United States)

    Salem, Ibrahim; Ghazala, Hosni; El Diasty, Waleed

    2015-12-01

    The occurrence of hydrocarbons is closely linked to the elements of petroleum system history of the BED 3 and Sitra 8 oilfields, which has created multiple reservoir and seal combinations. BED 3 Field and Sitra concessions occupy the northwestern part of the Abu Gharadig Basin and extends between latitudes 29°45‧ and 30°05‧N and longitudes 27°30‧ and 28°10‧E. The comprehensive integration of the geo-related data and the interpretation of the well logging, geochemical, seismic data in time domain and depth and sealing mechanisms explain the occurrence of hydrocarbons in some certain reservoirs during cretaceous age and other reservoirs in the same fields don't have any hydrocarbon accumulation. Detailed seismic data interpretation was performed for the target units of BED 3 and Sitra 8 oilfields in time domain and converted to depth domain. Sitra 8 Field is a three-way dip closure bounded by NW-SE faults while BED 3 field is represented by a WNW-ESE trending horst dipping to the east. The Albian-Cenomanian Kharita Formation has a high energy shallow marine shelf environment and considered as the main pay zone in the BED 3 oilfield. On the other hand, Kharita sands are dry in the Sitra 8 Field. Also, the shallow marine shale, sandstone, limestone and dolomite interbeds of the Abu Roash G Member are another hydrocarbon bearing reservoir in the Sitra 8 Field. Sealing mechanisms were applied to explain why certain reservoirs have hydrocarbon and others don't. Allan's juxtaposition diagram for the main faults in the study area shows that Kharita sands in BED 3 area have excellent juxtaposition as Kharita juxtapose to upper Bahariya and intra Bahariya, which consist of shale and limestone. Abu Roash G sands in BED 3 area have bad juxtaposition as the Abu Roash G juxtapose to Abu Roash C sand (sand juxtaposed sand). Allan's diagram shows that the Abu Roash G reservoir (main target) in Sitra 8 is juxtaposing Abu Roash D which is composed of limestone and shale

  8. Eocene lake basins in Wyoming and Nevada record rollback of the Farallon flat-slab beneath western North America

    Science.gov (United States)

    Smith, M. E.; Cassel, E. J.; Jicha, B. R.; Singer, B. S.; Carroll, A.

    2014-12-01

    Numerical and conceptual models of flat-slab rollback predict broad initial dynamic subsidence above the slab hinge then uplift and volcanism triggered by the advection of asthenosphere beneath the overriding plate. These predicted surface effects provide a viable but largely untested explanation for lake basin formation in Cordilleran-type orogenies. We argue that the hydrologic closure of both the foreland (early Eocene) and hinterland (late Eocene) of the North American Cordillera were caused by a trenchward-migrating wave of dynamic and thermal topography resulting from progressive removal of the Farallon flat-slab. Two major episodes of hydrologic drainage closure are recorded by Eocene terrestrial strata in the western United States. The first occurred in the retroarc foreland during the early Eocene, and resulted in the deposition of the Green River Fm. The second occurred in the hinterland during the late Eocene and resulted in accumulation of the Elko Fm. In both regions, lake strata overlie fluvial strata and become progressively more evaporative up-section, and are overlain by volcaniclastic strata. Both successions were then truncated by regional unconformities that extend until the Oligocene. We interpret these stratigraphic successions to record trenchward propagation of a regional topographic wave, caused by slab rollback. Migration of the slab-hinge initially caused dynamic subsidence and initiation of lacustrine deposition. Regional surface uplift followed, and was associated with scattered volcanism. Uplift promoted formation of endorheic basins and ultimately the development of regional unconformities. The height of the uplift can be roughly approximated by the preserved thickness of lacustrine and other nonmarine deposits at both locations (0.2-1.0 km). The 40Ar/39Ar and U-Pb geochronology of Green River Fm ash beds indicate that this surface topographic wave migrated trenchward (SW) across the foreland from 53 to 47 Ma at a velocity of ~6 cm

  9. Forecasting database for the tsunami warning center for the western Mediterranean and North-East Atlantic basins

    Science.gov (United States)

    Gailler, A.; Hebert, H.; Loevenbruck, A.; Hernandez, B.

    2011-12-01

    Improvements in the availability of sea-level observations and advances in numerical modeling techniques are increasing the potential for tsunami warnings to be based on numerical model forecasts. Numerical tsunami propagation and inundation models are well developed, but they present a challenge to run in real-time, partly due to computational limitations and also to a lack of detailed knowledge on the earthquake rupture parameters. A first generation model-based tsunami prediction system is being developed as part of the French Tsunami Warning Center that will be operational by mid 2012. It involves a pre-computed unit source functions database (i.e., a number of tsunami model runs that are calculated ahead of time and stored) corresponding to tsunami scenarios generated by a source of seismic moment 1.75E+19 N.m with a rectangular fault 25 km by 20 km in size and 1 m in slip. The faults of the unit functions are placed adjacent to each other, following the discretization of the main seismogenic faults bounding the western Mediterranean and North-East Atlantic basins. An authomatized composite scenarios calculation tool is implemented to allow the simulation of any tsunami propagation scenario (i.e., of any seismic moment). The strategy is based on linear combinations and scaling of a finite number of pre-computed unit source functions. The number of unit functions involved varies with the magnitude of the wanted composite solution and the combined wave heights are multiplied by a given scaling factor to produce the new arbitrary scenario. Uncertainty on the magnitude of the detected event and inaccuracy on the epicenter location are taken into account in the composite scenarios calculation. For one tsunamigenic event, the tool produces finally 3 warning maps (i.e., most likely, minimum and maximum scenarios) together with the rough decision matrix representation. A no-dimension code representation is chosen to show zones in the main axis of energy at the basin

  10. Distribution and variation of the inorganic fraction of Devonian to Bashkirian black shales in the north-western part of the Dniepr-Donets Basin, Ukraine

    Science.gov (United States)

    Wegerer, Eva; Sachsenhofer, Reinhard; Misch, David; Aust, Nicolai

    2016-04-01

    Mineralogical data of 112 core samples from 12 wells are used to investigate lateral and vertical variations in the lithofacies of Devonian to Bashkirian black shales in the north-western part of the Dniepr-Donets-Basin. Sulphur and carbonate contents as well as organic geochemical parameters, including TOC and Hydrogen Index have been determined on the same sample set within the frame of an earlier study (Sachsenhofer et al. 2010). This allows the correlation of inorganic and organic composition of the black shales. Aims of the study are to distinguish between detrital and authigenic minerals, to relate the lithofacies of the black shales with the tectono-stratigraphic sequences of the Dniepr-Donets Basin, to contribute to the reconstruction of the depositional environment and to relate diagenetic processes with the thermal history of the basin. Mineral compositions were determined primarily using XRD-measurements applying several measurement procedures, e.g. chemical and temperature treatment, and specific standards. Major differences exist in the mineralogical composition of the black shales. For example, clay mineral contents range from less than 20 to more than 80 Vol%. Kaolinite contents are significantly higher in rocks with a Tournaisian or Early Visean age than in any other stratigraphic unit. This is also true for two Lower Visean coal samples from the shallow north-westernmost part of the basin. Chlorite contents reach maxima in uppermost Visean and overlying rocks. Quartz contents are often high in Upper Visean rocks and reach maxima in Bashkirian units. Feldspar-rich rocks are observed in Devonian sediments from the north-western part of the study area and may reflect the proximity to a sediment source. Carbonate contents are typically low, but reach very high values in some Tournaisian, Lower Visean and Serpukhovian samples. Pyrite contents reach maxima along the basin axis in Tournaisian and Visean rocks reflecting anoxic conditions. Mixed layer

  11. Reserves in western basins

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  12. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  13. Hydrogeochemical and isotopic composition of groundwater in the Horgos River Watershed in the NorthWestern Ili Basin in Sinkiang Province, China

    Science.gov (United States)

    Jin, S. H.; Jiang, J. Y.; Rao, J. P.

    2016-08-01

    In this study, hydrogeochemical and stable environmental isotopic (oxygen-18 and deuterium) data of groundwater in the Horgos River watershed in the north-western Ili Basin were examined to determine the groundwater chemical characteristics, as well as the origins of the groundwater and surface water. The quaternary aquifer's structure and spatial distribution is complex. Hydrogeochemical data shows that the groundwater is alkaline due to the presence of bicarbonate as the dominant anion. In the north, the dominant groundwater cation was Ca2+ while Mg2+ ions were highest in the south. In addition, water types varied from HCO3-SO4-Ca and HCO3-SO4-Ca-Mg to HCO3-SO4-Mg-Ca and SO4-HCO3-Mg-Ca. Overall, the groundwater in this study showed high total hardness. The dissolving and evaporation inspissation were considered the main controlling factors. Isotopic data (oxygen-18 and deuterium) indicated that the Horgos River was the main recharge source for the groundwater, which rapidly infiltrated across sandstone macropores. Furthermore, surface water and shallow groundwater were significantly affected by evaporation.

  14. The nonmarine Lower Cretaceous of the North American Western Interior foreland basin: New biostratigraphic results from ostracod correlations and early mammals, and their implications for paleontology and geology of the basin—An overview

    Science.gov (United States)

    Sames, Benjamin; Cifelli, Richard L.; Schudack, Michael E.

    2010-08-01

    The timespan represented by the hiatus between nonmarine Upper Jurassic (Early Berriasian?) and unconformably overlying Lower Cretaceous deposits throughout the North American Western Interior foreland basin has been under discussion for the entire 20th century and remains controversial to date. Ongoing research in revision of Early Cretaceous nonmarine ostracods of some respective North American formations leads to a breakthrough concerning the verification of their biostratigraphic utility as well as their subsequent application. These ostracods are not as endemic as hitherto believed and can be used for supraregional and regional correlation, as well as improvement of the age determination of North American units. New results strongly suggest a maximum age of Late Berriasian to Valanginian (˜ 142-138 Ma) for the lower part of the Lakota (Black Hills area, South Dakota) and Cedar Mountain (Utah) formations. A pre-Aptian maximum age for the Lakota Formation is supported by early mammals. These biostratigraphic results affect the correlatable formations as well, and therefore have broad implications on basin-related geologic and paleontologic topics that are overviewed and discussed herein. The central issue hampering an integrated synthesis of the foreland basin is its yet imprecise chronostratigraphic framework and documentation. Temporal relationships between the gologic processes of the basin and their control factors are still insufficiently calibrated or controversial. Detailed ongoing revision of North American Early Cretaceous nonmarine ostracods demonstrates their applicability, utility, and further potential as tool for improvement of the chronostratigraphy of the Western Interior foreland basin at both small and large scales. These ostracods also foster understanding of animal (e.g. early mammals and dinosaurs) and plant (angiosperms) evolution on the North American continent and show promise of providing age determinations for single-sample horizons in

  15. Sedimentology and petrography of mass-emplaced limestone (Orahiri Limestone) on a late Oligocene shelf, western North Island, and tectonic implications for eastern margin development of Taranaki Basin

    International Nuclear Information System (INIS)

    The Te Kuiti Group in North Wanganui Basin, North Island, New Zealand, of Oligocene - earliest Miocene (Whaingaroan-Waitakian) age, is dominated by calcareous siltstone, calcareous sandstone, and skeletal limestone. Exposures in the southwestern corner of the basin at Awakino Tunnel are distinctive because, compared with elsewhere, the group is generally thicker (>300 m), has strong dips (25-45 degrees E), exhibits an up-section decrease in the amount of dip, and the capping Orahiri Limestone includes several thick (up to 3 m) mass-emplaced units containing a variety of 1-10 cm sized calcareous lithoclasts of older Te Kuiti Group rocks. Petrographic and δ18O and δ13C data suggest that the source deposits of these lithoclasts were cemented at relatively shallow subsurface burial depths (100-500 m) before their uplift and erosion. The lithoclasts so produced were rounded by abrasion in shoal water, often bored profusely by pholad bivalves, and sometimes encrusted by coralline algae, before being periodically mass-emplaced from west to east onto a shelf accumulating coeval Orahiri Limestone lithofacies now in the vicinity of Awakino Tunnel. Pressure-dissolution during subsequent burial provided the main source of calcite cement in the host Orahiri Limestone, mainly at moderate burial depths of 500-1000 m, according to δ18O data. The source region for the lithoclasts probably lay west of Awakino Tunnel and corresponds to the southern part of the basement Herangi High, which otherwise separates North Wanganui Basin from Taranaki Basin, but must have been submarine and accumulating Te Kuiti Group-equivalent calcareous facies during the early Oligocene (Early Whaingaroan, 36-32 Ma). Uplift of this depocentre was accompanied by synsedimentary eastward tilting of the Te Kuiti Group strata already deposited immediately east of Herangi High, contributing to the dips now measured at Awakino Tunnel. Inversion and tilting of the high began in the Late Whaingaroan, after 32 Ma

  16. Tectonic and thermal history of the western Serrania del Interior foreland fold and thrust belt and Guarico Basin, north central Venezuela: Implications of new apatite fission track analysis and seismic interpretation

    Science.gov (United States)

    Perez de Armas, Jaime Gonzalo

    Structural analysis, interpretation of seismic reflection lines, and apatite fission-track analysis in the Western Serrania del Interior fold and thrust belt and in the Guarico basin of north-central Venezuela indicate that the area underwent Mesozoic and Tertiary-to-Recent deformation. Mesozoic deformation, related to the breakup of Pangea, resulted in the formation of the Espino graben in the southernmost portion of the Guarico basin and in the formation of the Proto-Caribbean lithosphere between the diverging North and South American plates. The northern margin of Venezuela became a northward facing passive margin. Minor normal faults formed in the Guarico basin. The most intense deformation took place in the Neogene when the Leeward Antilles volcanic island arc collided obliquely with South America. The inception of the basal foredeep unconformity in the Late Eocene-Early Oligocene marks the formation of a perisutural basin on top of a buried graben system. It is coeval with minor extension and possible reactivation of Cretaceous normal faults in the Guarico basin. It marks the deepening of the foredeep. Cooling ages derived from apatite fission-tracks suggest that the obduction of the fold and thrust belt in the study area occurred in the Late Oligocene through the Middle Miocene. Field data and seismic interpretations suggest also that contractional deformation began during the Neogene, and specifically during the Miocene. The most surprising results of the detrital apatite fission-track study are the ages acquired in the sedimentary rocks of the easternmost part of the study area in the foreland fold and thrust belt. They indicate an Eocene thermal event. This event may be related to the Eocene NW-SE convergence of the North and South American plates that must have caused the Proto-Caribbean lithosphere to be shortened. This event is not related to the collision of the arc with South America, as the arc was far to the west during the Eocene.

  17. Long-range transport and mixing of aerosol sources during the 2013 North American biomass burning episode: analysis of multiple lidar observations in the western Mediterranean basin

    Science.gov (United States)

    Ancellet, Gerard; Pelon, Jacques; Totems, Julien; Chazette, Patrick; Bazureau, Ariane; Sicard, Michaël; Di Iorio, Tatiana; Dulac, Francois; Mallet, Marc

    2016-04-01

    Long-range transport of biomass burning (BB) aerosols between North America and the Mediterranean region took place in June 2013. A large number of ground-based and airborne lidar measurements were deployed in the western Mediterranean during the Chemistry-AeRosol Mediterranean EXperiment (ChArMEx) intensive observation period. A detailed analysis of the potential North American aerosol sources is conducted including the assessment of their transport to Europe using forward simulations of the FLEXPART Lagrangian particle dispersion model initialized using satellite observations by MODIS and CALIOP. The three-dimensional structure of the aerosol distribution in the ChArMEx domain observed by the ground-based lidars (Minorca, Barcelona and Lampedusa), a Falcon-20 aircraft flight and three CALIOP tracks, agrees very well with the model simulation of the three major sources considered in this work: Canadian and Colorado fires, a dust storm from western US and the contribution of Saharan dust streamers advected from the North Atlantic trade wind region into the westerlies region. Four aerosol types were identified using the optical properties of the observed aerosol layers (aerosol depolarization ratio, lidar ratio) and the transport model analysis of the contribution of each aerosol source: (i) pure BB layer, (ii) weakly dusty BB, (iii) significant mixture of BB and dust transported from the trade wind region, and (iv) the outflow of Saharan dust by the subtropical jet and not mixed with BB aerosol. The contribution of the Canadian fires is the major aerosol source during this episode while mixing of dust and BB is only significant at an altitude above 5 km. The mixing corresponds to a 20-30 % dust contribution in the total aerosol backscatter. The comparison with the MODIS aerosol optical depth horizontal distribution during this episode over the western Mediterranean Sea shows that the Canadian fire contributions were as large as the direct northward dust outflow

  18. Mesozoic basins and associated palaeogeographic evolution in North China

    Institute of Scientific and Technical Information of China (English)

    Yong-Qing Liu; Hong-Wei Kuang; Nan Peng; Huan Xu; Peng Zhang; Neng-Sheng Wang; Wei An

    2015-01-01

    complicated thrust and fold, the previous uniifed Ordos-North China Basin was separated by the northeast-oriented Great Xing’an Range and Taihang Mountain uplifted linearment. The differential evolution of basins and sedimentary palaeoge-ography between eastern and western North China was initiated, and was interpreted to result in the closure of Okhotsk Ocean and the subduction of Palaeo-Paciifc Plate (late stage 2). During the Late Jurassic (the early phase of stage 3), a variety of faulted basins occurred in the Yanshan and Yinshan areas in the northeastern North China. In Yanshan area, basins were iflled with thickened intermediate volcanic rocks and purple-red coarse-grained clastic rocks. In contrast, only thick layered sedimentary rocks with rare volcanic rocks developed in the Yinshan faulted basins, the Ordos Basin and basins in sourthern North China. XMOB was the main provenance of the Early Mesozoic basins in the North China, while the Ordos Basin and the Hefei Basin were partly supplied by the northern Qinling Orogenic Belt. During the Late Jurassic-early Early Cretaceous (the late phase of stage 3), the north-ern and northeastern North China experienced extensional movement after the subduction of the Palaeo-Paciifc Plate, the closure of the Mongolia-Okhotsk Ocean and the subsequent Yanshanian orogeny. At the same time, a NE-oriented, giant rift basin system (NE Asia Rift) extended from the Yanshan to the western Great Xing’an Range, where rift basins were iflled with the regional, NE-oriented, thick coarse-grained clastic rocks and a belt of volcanic rocks. In the meantime, the eastern and northeastern China and most areas of NCC were presented as highland terrains. During the middle-late Early Cretaceous (stage 4), rift basins developed and accumulated alluvial sediments and interbedded alkaline volcanic rocks in the western and northern North China, including Yingen, Ejinaqi and Erlian regions. Basins were formed on both sides of the Tan-Lu Fault Zone

  19. Basin deconstruction-construction: Seeking thermal-tectonic consistency through the integration of geochemical thermal indicators and seismic fault mechanical stratigraphy ​- Example from Faras Field, North Western Desert, Egypt

    Science.gov (United States)

    Pigott, John D.; Abouelresh, Mohamed O.

    2016-02-01

    To construct a model of a sedimentary basin's thermal tectonic history is first to deconstruct it: taking apart its geological elements, searching for its initial conditions, and then to reassemble the elements in the temporal order that the basin is assumed to have evolved. Two inherent difficulties implicit to the analysis are that most organic thermal indicators are cumulative, irreversible and a function of both temperature and time and the non-uniqueness of crustal strain histories which complicates tectonic interpretations. If the initial conditions (e.g. starting maturity of the reactants and initial crustal temperature) can be specified and the boundary conditions incrementally designated from changes in the lithospheric heat engine owing to stratigraphic structural constraints, then the number of pathways for the temporal evolution of a basin is greatly reduced. For this investigation, model input uncertainties are reduced through seeking a solution that iteratively integrates the geologically constrained tectonic subsidence, geochemically constrained thermal indicators, and geophysically constrained fault mechanical stratigraphy. The Faras oilfield in the Abu Gharadig Basin, North Western Desert, Egypt, provides an investigative example of such a basin's deconstructive procedure. Multiple episodes of crustal extension and shortening are apparent in the tectonic subsidence analyses which are constrained from the fault mechanical stratigraphy interpreted from reflection seismic profiles. The model was iterated with different thermal boundary conditions until outputs best fit the geochemical observations. In so doing, the thermal iterations demonstrate that general relationship that basin heat flow increases decrease vertical model maturity gradients, increases in surface temperatures shift vertical maturity gradients linearly to higher values, increases in sediment conductivities lower vertical maturities with depth, and the addition of "ghost" layers

  20. Rifting Thick Lithosphere - Canning Basin, Western Australia

    Science.gov (United States)

    Czarnota, Karol; White, Nicky

    2016-04-01

    The subsidence histories and architecture of most, but not all, rift basins are elegantly explained by extension of ~120 km thick lithosphere followed by thermal re-thickening of the lithospheric mantle to its pre-rift thickness. Although this well-established model underpins most basin analysis, it is unclear whether the model explains the subsidence of rift basins developed over substantially thick lithosphere (as imaged by seismic tomography beneath substantial portions of the continents). The Canning Basin of Western Australia is an example where a rift basin putatively overlies lithosphere ≥180 km thick, imaged using shear wave tomography. Subsidence modelling in this study shows that the entire subsidence history of the Canning Basin is adequately explained by mild Ordovician extension (β≈1.2) of ~120 km thick lithosphere followed by post-rift thermal subsidence. This is consistent with the established model, described above, albeit with perturbations due to transient dynamic topography support which are expressed as basin-wide unconformities. In contrast the Canning Basin reveals an almost continuous period of normal faulting between the Ordovician and Carboniferous (βCanning Basin to rifting of thick lithosphere beneath the eastern part, verified by the presence of ~20 Ma diamond-bearing lamproites intruded into the basin depocentre. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted in density by 50-70 kg m-3, which is in line with estimates derived from modelling rare-earth element concentrations of the ~20 Ma lamproites and global isostatic considerations. Together, these results suggest that thick lithosphere thinned to > 120 km is thermally stable and is not accompanied by post-rift thermal subsidence driven by thermal re-thickening of the lithospheric mantle. Our results show that variations in lithospheric thickness place a fundamental control on basin architecture

  1. Aggradation of gravels in tidally influenced fluvial systems: Upper Albian (Lower Cretaceous) on the cratonic margin of the North American Western Interior foreland basin

    Science.gov (United States)

    Brenner, Richard L.; Ludvigson, Greg A.; Witzke, B.L.; Phillips, P.L.; White, T.S.; Ufnar, David F.; Gonzalez, Luis A.; Joeckel, R.M.; Goettemoeller, A.; Shirk, B.R.

    2003-01-01

    Alluvial conglomerates were widely distributed around the margin of the Early Cretaceous North American Cretaceous Western Interior Seaway (KWIS). Conglomerates, sandstones, and lesser amounts of mudstones of the upper Albian Nishnabotna Member of the Dakota Formation were deposited as fill-in valleys that were incised up to 80 m into upper Paleozoic strata. These paleovalleys extended southwestward across present-day northwestern Iowa into eastern Nebraska. Conglomerate samples from four localities in western Iowa and eastern Nebraska consist mostly of polycrystalline quartz with lesser amounts of microcrystalline (mostly chert), and monocrystalline quartz. Previous studies discovered that some chert pebbles contain Ordovician-Pennsylvanian invertebrate fossils. The chert clasts analyzed in this study were consistent with these findings. In addition, we found that non-chert clasts consist of metaquartzite, strained monocrystalline quartz and 'vein' quartz from probable Proterozic sources, indicating that parts of the fluvial system's sediment load must have travelled distances of 400-1200 km. The relative tectonic stability of this subcontinent dictated that stream gradients were relatively low with estimates ranging from 0.3 to 0.6 m/km. Considering the complex sedimentologic relationships that must have been involved, the ability of low-gradient easterly-sourced rivers to entrain gravel clasts was primarily a function of paleodischarge rather than a function of steep gradients. Oxygen isotopic evidence from Albian sphaerosiderite-bearing paleosols in the Dakota Formation and correlative units from Kansas to Alaska suggest that mid-latitude continental rainfall in the Albian was perhaps twice that of the modern climate system. Hydrologic fluxes may have been related to wet-dry climatic cycles on decade or longer scales that could account for the required water supply flux. Regardless of temporal scale, gravels were transported during 'high-energy' pulses, under

  2. Application of the dating by fission tracks to determine thermicity of basins within petroleum potentialities: example of Sbaa and Ahnet-North basins located in Western Saharan platform, Algeria

    International Nuclear Information System (INIS)

    The interpretation of old fundamental research works and the results obtained by this study based on: the analysis of apatite fission tracks (AFT), the burial evolution curves and the sequential analysis of outcrop section, as well as the curves of signal of gamma ray (GR) analysis from drilling wells, allow to precise that the geodynamic evolution of the studied Algerian sedimentary basins (Ahnet and Sbaa) have been occurred principally in the Paleozoic era. The analysis of burial evolution curves shows that during the Paleozoic period, the sedimentation is controlled by the tectonic subsidence, particularly at the end of Carboniferous in the favor of Ougarta folding. The curves indicate an uplift from the Permian to middle Jurassic, expressed by an important erosion of sedimentary series and is considered as a response of thermal convection of the Saharan platform followed by thermal subsidence. This can be explained by the halt motion of rift extension caused by the opening of the Atlantic Ocean. To bring the sequential analysis out, it appears that Ahnet and Sbaa basins present contrasted stratigraphic recordings, so much in time than in space, indicated the different effects from subsidence and erosions according to their sectors. In thermal point of view, temperatures are still moderate in Sbaa depression and favorite the preservation of organic matter and might generate hydrocarbons until now. However, these conditions are not similar to ones in the case of Ahnet basin. In the North part of Ahnet basin (MRS-1, MSL-1), the ages are around 50 Ma, attested that sedimentary layers have been sustained a post-Hercynian thermal phase. This phase could be estimated probably more than 100 C. This is also produced during the regional extension of the Triassic-Jurassic rifting. This episode could also be responsible of disappearance (total?) of pre-existence fission tracks in the Devonian layers of the well MSR-1, which exhibits at the depth 505 m under the Hercynian

  3. Basin and Range Province, Western US, USGS Grids, #1

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  4. Basin and Range Province, Western US, USGS Grids #3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  5. Basin and Range Province, Western US, USGS Grids #2

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These grid files were used to produce gravity and basin depth maps of the Basin and Range Province, western United States. The maps show gravity values and modeled...

  6. Browning boreal forests of western North America

    Science.gov (United States)

    Verbyla, David

    2011-12-01

    , suggesting that direct temperature stress might be a factor in some species. Since warm growing seasons are also typically dry growing seasons, direct temperature stress and moisture stress could occur simultaneously. For example, 2004 was the warmest summer in over 200 years in boreal Alaska (Barber et al 2004) but it was also during a drought with less than 50 mm of summer precipitation recorded in Fairbanks. In Fairbanks, the length of the growing season, as defined as the period above freezing, has increased by 45 per cent over the past 100 years, with no significant increase in precipitation (Wendler and Shulski 2009). Regional winter runoff has increased, likely associated with permafrost thawing (Brabets and Walvoord 2009), while surface water has decreased, likely associated with increased evapotranspiration (Riordan et al 2006, Anderson et al 2007, Berg et al 2009). The mean annual air temperature in boreal Alaska has increased by over 1.5 °C during the past 50 years (Stafford et al 2000), and is projected to increase by 3-7 °C by end of this century (Walsh et al 2008). Thus, it would be surprising if a declining NDVI trend was not occurring in the western boreal region of North America as the climate continues to warm. Insects and disease in the North American boreal forest may also affect the NDVI browning trends (Malmström and Raffa 2000), as the life histories of damaging insects may be linked to a warming boreal climate. For example, warmer temperatures contributed to the spruce beetle outbreaks in Alaska with a reduction in the beetle life cycle from two years to one year (Berg et al 2006). Thus, as the boreal climate continues to warm, tree growth reduction and mortality from insects and diseases may become more substantial. In boreal Alaska, recent alder dieback and mortality is likely to be related to alder's susceptibility to a canker-causing fungus in drought years (Ruess et al 2009). Recent widespread and prolonged outbreaks of aspen leaf miner and a

  7. Using 14C and 3H to delineate a recharge ‘window’ into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia

    International Nuclear Information System (INIS)

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009–2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths (∼ 50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes (14C and 3H) and hydrochemical modelling were used to assess the presence of a recharge ‘window’ as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO2. Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1–2 mmol kg−1 of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge ‘window’. This study delineates a recharge ‘window’ into the commonly presumed

  8. Using {sup 14}C and {sup 3}H to delineate a recharge 'window' into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia

    Energy Technology Data Exchange (ETDEWEB)

    Meredith, Karina, E-mail: kmj@ansto.gov.au [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Cendon, Dioni I. [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Pigois, Jon-Philippe [Department of Water, PO Box K822 Perth WA 6842 (Australia); Hollins, Suzanne; Jacobsen, Geraldine [Australian Nuclear Science and Technology Organisation, Institute for Environmental Research, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)

    2012-01-01

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009-2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths ({approx} 50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes ({sup 14}C and {sup 3}H) and hydrochemical modelling were used to assess the presence of a recharge 'window' as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO{sub 2}. Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1-2 mmol kg{sup -1} of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge 'window'. This study delineates a recharge

  9. Using 14C and 3H to delineate a recharge 'window' into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia.

    Science.gov (United States)

    Meredith, Karina; Cendón, Dioni I; Pigois, Jon-Philippe; Hollins, Suzanne; Jacobsen, Geraldine

    2012-01-01

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009-2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths (~50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes ((14)C and (3)H) and hydrochemical modelling were used to assess the presence of a recharge 'window' as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO(2). Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1-2 mmol kg(-1) of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge 'window'. This study delineates a recharge 'window' into the commonly presumed confined

  10. Using 14C and 3H to delineate a recharge 'window' into the Perth Basin aquifers, North Gnangara groundwater system, Western Australia.

    Science.gov (United States)

    Meredith, Karina; Cendón, Dioni I; Pigois, Jon-Philippe; Hollins, Suzanne; Jacobsen, Geraldine

    2012-01-01

    The Gnangara Mound and the underlying Perth Basin aquifers are the largest source of groundwater for the southwest of Australia, supplying between 35 and 50% of Perth's potable water (2009-2010). However, declining health of wetlands on the Mound coupled with the reduction in groundwater levels from increased irrigation demands and drier climatic conditions means this resource is experiencing increased pressures. The northern Gnangara is an area where the Yarragadee aquifer occurs at shallow depths (~50 m) and is in direct contact with the superficial aquifer, suggesting the possibility of direct recharge into a generally confined aquifer. Environmental isotopes ((14)C and (3)H) and hydrochemical modelling were used to assess the presence of a recharge 'window' as well as understand the groundwater residence time within different aquifers. Forty-nine groundwater samples were collected from depths ranging from 11 to 311 m below ground surface. The isotopic variation observed in the superficial aquifer was found to be controlled by the different lithologies present, i.e. quartz-rich Bassendean Sand and carbonate-rich sediments of the Ascot Formation. Rainfall recharge into the Bassendean Sand inherits its dissolved inorganic carbon from the soil CO(2). Organic matter throughout the soil profile is degraded by oxidation leading to anoxic/acidic groundwater, which if in contact with the Ascot Formation leads to enhanced dissolution of carbonates. Hydrochemical mass balance modelling showed that carbonate dissolution could contribute 1-2 mmol kg(-1) of carbon to groundwaters recharged through the Ascot Formation. The corrected groundwater residence times of the Yarragadee aquifer in the northern part of the study area ranged from 23 to 35 ka, while waters in the southeastern corner ranged from sub-modern to 2 ka. Groundwater ages increase with distance radiating from the recharge 'window'. This study delineates a recharge 'window' into the commonly presumed confined

  11. The probability of tropical cyclone landfalls in Western North Pacific

    Science.gov (United States)

    Bonazzi, A.; Bellone, E.; Khare, S.

    2012-04-01

    The Western North Pacific (WNP) is the most active basin in terms of tropical cyclone and typhoon occurrences. The densely populated countries that form the western boundary of WNP basin -- e.g. China, Japan and the Philippines -- are exposed to extreme wind gusts, storm surge and fresh water flooding eventually triggered by Tropical Cyclones (TC) events. Event-based catastrophe models (hereafter cat models) are extensively used by the insurance industry to manage their exposure against low-frequency/high-consequence events such as natural catastrophes. Cat models provide their users with a realistic set of stochastic events that expands the scope of a historical catalogue. Confidence in a cat model ability to extrapolate peril and loss statistics beyond the period covered by observational data requires good agreement between stochastic and historical peril characteristics at shorter return periods. In WNP risk management practitioners are faced with highly uncertain data to base their decisions. Albeit 4 national agencies maintain best track catalogues, data are generally based on satellite imageries with very limited central pressure (CP) and maximum velocity (VMAX) measurements -- regular flight reconnaissance missions stopped in 1987. As a result differences up to 20 knots are found in estimates of VMAX from different agencies as documented in experiment IOP-10 during Typhoon Megi in 2010. In this work we present a comprehensive analysis of CP and VMAX probability distributions at landfall across the WNP basin along a set of 150 gates (100 km coast segments) based on best track catalogues from Japan Meteorological Agency, Joint Typhoon Warning Center, China Meteorological Agency and Hong Meteorological Agency. Landfall distributions are then used to calibrate a random-walk statistical track model. A long simulation of 100,000 years of statistical TC tracks will ultimately constitute the central building block of a basin-wide stochastic catalogue of synthetic TC

  12. Determination of properties of Proterozoic continental flood basalts of western part from North Qilian Mountains

    Institute of Scientific and Technical Information of China (English)

    夏林圻; 夏祖春; 赵江天; 徐学义; 杨合群; 赵东宏

    1999-01-01

    Proterozoic volcanic rocks of the western part from the North Qilian Mountains are the products of continental rift volcanism, belonging to continental flood basalts, the petrogeochemistry of which apears to suggest that they are derived from sub-lithospheric mantle plume sources, but that they also show evidence of continental lithosphere components involvement. Their formation is the consequences of plume-lithosphere interactions and is precursive to the opening of the North Qilian Early-Paleozoic ocean basin.

  13. Extreme winds in the Western North Pacific

    DEFF Research Database (Denmark)

    Ott, Søren

    2006-01-01

    A statistical model for extreme winds in the western North Pacific is developed, the region on the Planet where tropical cyclones are most common. The model is based on best track data derived mostly from satellite images of tropical cyclones. The methodsused to estimate surface wind speeds from...... they are at least coherent over time in their imperfections. Applying the the Holland model to the best track data, wind profiles can be assigned along the tracks. Fromthis annual wind speed maxima at any particular point in the region can be derived. The annual maxima, in turn, are fitted to a Gumbel distribution...... using a generalization Abild’s method that allows for data wind collected from multiple positions. Thechoice of this method is justified by a Monte Carlo simulation comparing it to two other methods. The principle output is a map showing fifty year winds in the region. The method is tested against...

  14. Paleogene palaeogeography and basin evolution of the Western Carpathians, Northern Pannonian domain and adjoining areas

    Science.gov (United States)

    Kováč, Michal; Plašienka, Dušan; Soták, Ján; Vojtko, Rastislav; Oszczypko, Nestor; Less, György; Ćosović, Vlasta; Fügenschuh, Bernhard; Králiková, Silvia

    2016-05-01

    The data about the Paleogene basin evolution, palaeogeography, and geodynamics of the Western Carpathian and Northern Pannonian domains are summarized, re-evaluated, supplemented, and newly interpreted. The presented concept is illustrated by a series of palinspastic and palaeotopographic maps. The Paleogene development of external Carpathian zones reflects gradual subduction of several oceanic realms (Vahic, Iňačovce-Kričevo, Szolnok, Magura, and Silesian-Krosno) and growth of the orogenic accretionary wedge (Pieniny Klippen Belt, Iňačovce-Kričevo Unit, Szolnok Belt, and Outer Carpathian Flysch Belt). Evolution of the Central Western Carpathians is characterized by the Paleocene-Early Eocene opening of several wedge-top basins at the accretionary wedge tip, controlled by changing compressional, strike-slip, and extensional tectonic regimes. During the Lutetian, the diverging translations of the northward moving Eastern Alpine and north-east to eastward shifted Western Carpathian segment generated crustal stretching at the Alpine-Carpathian junction with foundation of relatively deep basins. These basins enabled a marine connection between the Magura oceanic realm and the Northern Pannonian domain, and later also with the Dinaridic foredeep. Afterwards, the Late Eocene compression brought about uplift and exhumation of the basement complexes at the Alpine-Carpathian junction. Simultaneously, the eastern margin of the stretched Central Western Carpathians underwent disintegration, followed by opening of a fore-arc basin - the Central Carpathian Paleogene Basin. In the Northern Hungarian Paleogene retro-arc basin, turbidites covered a carbonate platform in the same time. During the Early Oligocene, the rock uplift of the Alpine-Carpathian junction area continued and the Mesozoic sequences of the Danube Basin basement were removed, along with a large part of the Eocene Hungarian Paleogene Basin fill, while the retro-arc basin depocentres migrated toward the east

  15. 77 FR 26001 - Southwest Power Pool; Western Area Power Administration; Basin Electric Cooperative; Heartland...

    Science.gov (United States)

    2012-05-02

    ... Energy Regulatory Commission Southwest Power Pool; Western Area Power Administration; Basin Electric Cooperative; Heartland Consumers Power District; Notice of Petition for Declaratory Order Take notice that on... Administration (Western), Basin Electric Power Cooperative (Basin Electric), and Heartland Consumers...

  16. Western Gas Sands Project: stratigrapy of the Piceance Basin

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, S. (comp.)

    1980-08-01

    The Western Gas Sands Project Core Program was initiated by US DOE to investigate various low permeability, gas bearing sandstones. Research to gain a better geological understanding of these sandstones and improve evaluation and stimulation techniques is being conducted. Tight gas sands are located in several mid-continent and western basins. This report deals with the Piceance Basin in northwestern Colorado. This discussion is an attempt to provide a general overview of the Piceance Basin stratigraphy and to be a useful reference of stratigraphic units and accompanying descriptions.

  17. Structural Architecture and Evolution of Kumkuli Basin, North Tibet

    Institute of Scientific and Technical Information of China (English)

    He Bizhu; Xu Zhiqin; Jiao Cunli; Cui Junwen; Wang Shenglang; Wang Gonghuai; Li Zhaoyang; Qiu Zhuli

    2009-01-01

    Utilizing the new data of gravity, magnetic, and magnetotelluric survey, we analyzed the characteristics of the three geophysical attribute (gravity, magnetic, and resistivity) interfaces and the deep architecture and structure of Kumkuli basin. The research results can provide basic data for early basin structural study. From coupled basin and mountain system, analysis of the structure, and evolution of Knmknli basin, we found that there was zoning from north to south and from west to east. Kumkuli basin has three structural architecture layers including metamorphic crystallization basement, fold basement and sedimentary cover. Knmkuli basin can be divided into three structural units, two depressions, and one uplift. Structural evolution of the Kumkuli basin can be divided into five evolution stages, including Kumkuli microcontinent formed in Sinian-Ordovician, suture around Kumkuli basin formed in Eopaleozoic, retroarc foreland basin formed in Neopaleozoic, rejuvenated foreland hasin developed in Mesozoic, and strike slip and compression basin developed in Cenozoic.

  18. Evolution, Migration, Controlling Factors and Forming Setting of Mesozoic Basins in Western Shandong

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhongyi; WU Ganguo; GUO Jinghui; ZHANG Da

    2005-01-01

    The distinctive topography in western Shandong province consists of several NW-WNW-trending mountain ranges and intervening basins.Basins,in which late-stage sediments to the south have progressively overlapped the earlier sediments and "basement" rocks of the hanging-wall block,are bounded by S-SW-dipping normal faults to the north.Basin analysis reveals the Jurassic-Cretaceous sedimentary rocks accumulated both within the area of crustal extension and during extensional deformation; they contain a record of a sequence of tectonic events during stretching and can be divided into four tectonic-sequence episodes.These basins were initially developed as early as ca.200 Ma in the northern part of the study area,extending dominantly N-S from the Early Jurassic until the Late Cretaceous.Although with a brief hiatus due to changes in stress field,to keep uniform N-S extensional polarity in such a long time as 130 Ma requires a relatively stable tectonic controlling factor responsible for the NW- and E-W-extensional basins.The formation of the extensional basins is partly concurrent with regional magmatism,but preceded magmatism by 40 Ma.This precludes a genetic link between local magmatism and extension during the Mesozoic.Based on integrated studies of basins and deformation,we consider that the gravitational collapse of the early overthickened continental crust may be the main tectonic driver for the Mesozoic extensional basins.From the Early Jurassic,dramatic reduction in north-south horizontal compressive stress made the western Shandong deformation belt switch from a state of failure under shortening to one dominated by extension and the belt gravitationally collapsed and horizontally spread to the south until equilibrium was established; synchronously,the normal faults and basins were developed based on the model of simple-shear extensional deformation.This may be relative to the gravitational collapse of the Mesozoic plateau in eastern China.

  19. Classification of Complex Reservoirs in Superimposed Basins of Western China

    Institute of Scientific and Technical Information of China (English)

    PANG Xiongqi; ZHOU Xinyuan; LIN Changsong; HUO Zhipeng; LUO Xiaorong; PANG Hong

    2010-01-01

    Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins.The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation,stratigraphic structure and stratigraphic stress-strain action over geological history.Based on the correlation of chronological age on structural sections,superimposed basins can be divided into five types in this study:(1)continuous sedimentation type superimposed basins,(2)middle and late stratigraphic superimposed basins,(3)early and late stratigraphic superimposed basins,(4)early and middle stratigraphic superimposed basins,and(5)long-term exposed superimposed basins.Multiple source-reservoir-caprock assemblages have developed in such basins.In addition,multi-stage hydrocarbon generation and expulsion,multiple sources,polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment,reformation and destruction have occurred in these basins.The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs,and the root causes of this are folding,denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage,diffusion,spilling,oxidation,degradation and cracking.Based on their genesis characteristics,complex reservoirs are divided into five categories:(1)primary reservoirs,(2)trap adjustment type reservoirs,(3)component variant reservoirs,(4)phase conversion type reservoirs and(5)scale-reformed reservoirs.

  20. RESERVES IN WESTERN BASINS PART IV: WIND RIVER BASIN

    Energy Technology Data Exchange (ETDEWEB)

    Robert Caldwell

    1998-04-01

    Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies

  1. Extreme winds in the Western North Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Ott, S.

    2006-11-15

    A statistical model for extreme winds in the western North Pacific is developed, the region on the Planet where tropical cyclones are most common. The model is based on best track data derived mostly from satellite images of tropical cyclones. The methods used to estimate surface wind speeds from satellite images is discussed with emphasis on the empirical basis, which, unfortunately, is not very strong. This is stressed by the fact that Japanese and US agencies arrive at markedly different estimates. On the other hand, best track data records cover a long period of time and if not perfect they are at least coherent over time in their imperfections. Applying the the Holland model to the best track data, wind profiles can be assigned along the tracks. From this annual wind speed maxima at any particular point in the region can be derived. The annual maxima, in turn, are fitted to a Gumbel distribution using a generalization Abild's method that allows for data wind collected from multiple positions. The choice of this method is justified by a Monte Carlo simulation comparing it to two other methods. The principle output is a map showing fifty year winds in the region. The method is tested against observed winds from Philippine synoptic stations and fair agreement is found for observed and predicted 48 year maxima. However, the almost biasfree performance of the model could be fortuitous, since precise definitions of 'windspeed' in terms averaging time, height above ground and assumed surface roughness are not available, neither for best tracks nor for the synoptic data. The work has been carried out under Danish Research Agency grant 2104-04-0005 'Offshore wind power' and it also covers the findings and analysis carried out in connection with task 1.6 of the project 'Feasibility Assessment and Capacity Building for Wind Energy Development in Cambodia, The Philippines and Vietnam' during 2005-06 under contract 125-2004 with EU

  2. Coalbed gas potential in the miocene Soma basin (Western Turkey)

    OpenAIRE

    İnan, Sedat; Inan, Sedat; Baysal, Mustafa; YÜRÜM, YUDA; Yurum, Yuda

    2010-01-01

    The Neogene Basins of Turkey contain as much as 9 billion tons of lignite-rank coal (Sengiller, 2001; Tuncah et al., 2002). The Miocene Soma Basin, a rift basin trending NE-SW (approximately 20 kilometers by 5 kilometers) in the Aegean Extensional Province (EAP) of Western Turkey, is estimated to contain at the least one billion tons of lignite and about half of this reserve is present at depths greater than 600 m (Turkish Coal Enterprises, 2006). Miocene marillimestone units and Pliocene cla...

  3. North Park Basin, Colorado, for 1999 National Coal Resource Assessment

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This ArcView shapefile contains a polygon representing the extent of the North Park coal basin boundary. This theme was created specifically for the National Coal...

  4. Landslide Inventory for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase is an inventory of existing landslides in the Little North Santiam River Basin, Oregon (2009). Each landslide feature shown has been classified...

  5. Risk Assessment for Yellow Fever in Western and North-Western Provinces of Zambia

    OpenAIRE

    Babaniyi, Olusegun A; Peter Mwaba; David Mulenga; Mwaka Monze; Peter Songolo; Mazyanga L Mazaba-Liwewe; Idah Mweene-Ndumba; Freddie Masaninga; Elizabeth Chizema; Messeret Eshetu-Shibeshi; Costantine Malama; Emmanuel Rudatsikira; Seter Siziya

    2015-01-01

    Background: North-Western and Western provinces of Zambia were reclassified as low-risk areas for yellow fever (YF). However, the current potential for YF transmission in these areas is unclear. Aims: To determine the current potential risk of YF infection. Setting and Design: A cross sectional study was conducted in North-Western and Western provinces of Zambia. Materials and Methods: Samples were tested for both YF virus-specific IgG and IgM antibodies by the ELISA and YF virus confirmation...

  6. Reserves in western basins: Part 1, Greater Green River basin

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    This study characterizes an extremely large gas resource located in low permeability, overpressured sandstone reservoirs located below 8,000 feet drill depth in the Greater Green River basin, Wyoming. Total in place resource is estimated at 1,968 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 33 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. Five plays (formations) were included in this study and each was separately analyzed in terms of its overpressured, tight gas resource, established productive characteristics and future reserves potential based on a constant $2/Mcf wellhead gas price scenario. A scheme has been developed to break the overall resource estimate down into components that can be considered as differing technical and economic challenges that must be overcome in order to exploit such resources: in other words, to convert those resources to economically recoverable reserves. Total recoverable reserves estimates of 33 Tcf do not include the existing production from overpressured tight reservoirs in the basin. These have estimated ultimate recovery of approximately 1.6 Tcf, or a per well average recovery of 2.3 Bcf. Due to the fact that considerable pay thicknesses can be present, wells can be economic despite limited drainage areas. It is typical for significant bypassed gas to be present at inter-well locations because drainage areas are commonly less than regulatory well spacing requirements.

  7. Reserve estimates in western basins. Part 2: Piceance Basin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This study characterizes an extremely large gas resource located in low permeability, sandstone reservoirs of the Mesaverde group in the Piceance Basin, Colorado. Total in place resource is estimated at 307.3 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 5.8 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. About 82.6% of the total evaluated resource is contained within sandstones that have extremely poor reservoir properties with permeabilities considered too low for commerciality using current frac technology. Cost reductions and technology improvements will be required to unlock portions of this enormous resource. Approximately 2.7% of the total resource is contained within sandstone reservoirs which do not respond to massive hydraulic fracture treatments, probably due to their natural lenticular nature. Approximately 6.8% of the total resource is located in deeply buried settings below deepest established production. Approximately 7.9% of the total resource is considered to represent tight reservoirs that may be commercially exploited using today`s hydraulic fracturing technology. Recent technology advances in hydraulic fracturing practices in the Piceance Basin Mesaverde has resulted in a marked improvement in per well gas recovery which, where demonstrated, has been incorporated into the estimates provided in this report. This improvement is so significant in changing the risk-reward relationship that has historically characterized this play, that previously uneconomic areas and resources will graduate to the economically exploitable category. 48 refs., 96 figs., 18 tabs.

  8. Exploitation Contradictions Concerning Multi-Energy Resources among Coal, Gas, Oil, and Uranium: A Case Study in the Ordos Basin (Western North China Craton and Southern Side of Yinshan Mountains

    Directory of Open Access Journals (Sweden)

    Xiaowei Feng

    2016-02-01

    Full Text Available The particular “rich coal, meager oil, and deficient gas” energy structure of China determines its high degree of dependence on coal resources. After over 100 years of high-intensity mining activities in Northeast China, East Region, and the Southern Region, coal mining in these areas is facing a series of serious problems, which force China’s energy exploitation map to be rewritten. New energy bases will move to the western and northern regions in the next few years. However, overlapping phenomena of multiple resources are frequently encountered. Previous exploitation mainly focused on coal mining, which destroys many mutualistic and accompanying resources, such as uranium, gas, and oil. Aiming at solving this unscientific development mode, this research presents a case study in the Ordos Basin, where uranium, coal, and gas/oil show a three-dimensional overlapping phenomenon along the vertical downward direction. The upper uranium and lower coal situation in this basin is remarkable; specifically, coal mining disturbs the overlaying aquifer, thus requiring the uranium to be leached first. The technical approach must be sufficiently reliable to avoid the leakage of radioactive elements in subsequent coal mining procedures. Hence, the unbalanced injection and extraction of uranium mining is used to completely eradicate the discharged emissions to the environment. The gas and oil are typically not extracted because of their deep occurrence strata and their overlapping phenomenon with coal seams. Use of the integrated coal and gas production method is recommended, and relevant fracturing methods to increase the gas migrating degree in the strata are also introduced. The results and recommendations in this study are applicable in some other areas with similarities.

  9. Campanian Climatic Change: Isotopic Evidence from Far East, North America, North Atlantic and Western Europe

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Paleoclimatic settings have been reconstructed for the Campanian using original oxygenisotopic analyses of well-preserved molluskan and foraminifera shells from Russian Far East,Hokkaido, USA, Belgium and some DSDP holes (95, 98, 102, 390A, and 392A) in North Atlantic. Early Early Campanian climatic optimum has been recognized from data on high bottom shelf water paleotemperatures in middle latitudes of both the western circum-Pacific (to 24.2℃) and the eastern circum-Pacific (to 26.4℃) areas and high bottom shallow water paleotemperatures in high latitudes of the Koryak Upland (22.4-25.5℃), which agrees with the data on the Campanian Barykovskaya flora in high latitudes (Golovneva and Herman, 1998) and Jonker flora and its equivalents in middle latitudes. Judging from the data on comparatively high bottom shallow water paleotemperature values in high latitudes, South Alaska (19.4℃) and the Koryak Upland (22.4-25.5℃), we also expect Latest Campanian temperature maximum, which has not been confirmed, however, for low and middle latitudes by neither of isotopic nor paleobotanic data now. Main climatic tendency during the Campanian (with the exception of Latest Campanian) has been learned from isotopic composition of Campanian aragonitic ammonoid shells from the Hokkaido-South Sakhalin (Krilyon) marine basin.In contrary to Huber's et al. (2002) assumption, we expect warm greenhouse conditions during the most part of the Campanian.

  10. Monitoring species richness and abundance of shorebirds in the western Great Basin

    Science.gov (United States)

    Warnock, N.; Haig, Susan M.; Oring, L.W.

    1998-01-01

    Broad-scale avian surveys have been attempted within North America with mixed results. Arid regions, such as the Great Basin, are often poorly sampled because of the vastness of the region, inaccessibility of sites, and few ornithologists. In addition, extreme variability in wetland habitat conditions present special problems for conducting censuses of species inhabiting these areas. We examined these issues in assessing multi-scale shorebird (order: Charadriiformes) censuses conducted in the western Great Basin from 1992-1997. On ground surveys, we recorded 31 species of shorebirds, but were unable to accurately estimate population size. Conversely, on aerial surveys we were able to estimate regional abundance of some shorebirds, but were unable to determine species diversity. Aerial surveys of three large alkali lakes in Oregon (Goose, Summer, and Abert Lakes) revealed > 300,000 shorebirds in one year of this study, of which 67% were American Avocets (Recurvirostra americana) and 30% phalaropes (Phalaropus spp.). These lakes clearly meet Western Hemisphere Shorebird Reserve Network guidelines for designation as important shorebird sites. Based upon simulations of our monitoring effort and the magnitude and variation of numbers of American Avocets, detection of S-10% negative declines in populations of these birds would take a minimum of 7-23 years of comparable effort. We conclude that a combination of ground and aerial surveys must be conducted at multiple sites and years and over a large region to obtain an accurate picture of the diversity, abundance, and trends of shorebirds in the western Great Basin.

  11. Cortinarius bovarius (Agaricales, a new species from western North America

    Directory of Open Access Journals (Sweden)

    Kare Liimatainen

    2013-05-01

    Full Text Available Cortinarius bovarius sp. nov., a conifer associated taxon growing on calcareous ground, is described from western North America. Phylogenetic relationships and species limits were investigated using rDNA ITS and nuclear rpb2 sequences, morphological and ecological data. The species belongs to section Bovini and its closest relative is European C. bovinus.

  12. CHARACTERIZATION OF WESTERN NORTH ATLANTIC RIGHT WHALE SPRING FEEDING HABITAT

    Science.gov (United States)

    The Great South Channel region of the southwestern Gulf of Maine, between George's Bank and Cape Cod, is the primary spring feeding ground for the western North Atlantic population of the I northern right whale, E. glacialis .Since this whale is so endangered, it is critical to i...

  13. Diversity of Pseudo-nitzschia from the western North Pacific

    DEFF Research Database (Denmark)

    Stonik, Inna V; Orlova, Tatiana Yu; Lundholm, Nina

    2011-01-01

    Asurvey focusing on species belonging to the diatom genus Pseudo-nitzschia was conducted in the western North Pacific (the northwestern Sea of Japan and the Sea of Okhotsk). Light and electron microscopic examination of 314 phytoplankton field samples collected from 1995 to 2006 revealed the pres...

  14. Tectono-stratigraphic evolution and crustal architecture of the Orphan Basin during North Atlantic rifting

    Science.gov (United States)

    Gouiza, Mohamed; Hall, Jeremy; Welford, J. Kim

    2016-06-01

    The Orphan Basin is located in the deep offshore of the Newfoundland margin, and it is bounded by the continental shelf to the west, the Grand Banks to the south, and the continental blocks of Orphan Knoll and Flemish Cap to the east. The Orphan Basin formed in Mesozoic time during the opening of the North Atlantic Ocean between eastern Canada and western Iberia-Europe. This work, based on well data and regional seismic reflection profiles across the basin, indicates that the continental crust was affected by several extensional episodes between the Jurassic and the Early Cretaceous, separated by events of uplift and erosion. The preserved tectono-stratigraphic sequences in the basin reveal that deformation initiated in the eastern part of the Orphan Basin in the Jurassic and spread towards the west in the Early Cretaceous, resulting in numerous rift structures filled with a Jurassic-Lower Cretaceous syn-rift succession and overlain by thick Upper Cretaceous to Cenozoic post-rift sediments. The seismic data show an extremely thinned crust (4-16 km thick) underneath the eastern and western parts of the Orphan Basin, forming two sub-basins separated by a wide structural high with a relatively thick crust (17 km thick). Quantifying the crustal architecture in the basin highlights the large discrepancy between brittle extension localized in the upper crust and the overall crustal thinning. This suggests that continental deformation in the Orphan Basin involved, in addition to the documented Jurassic and Early Cretaceous rifting, an earlier brittle rift phase which is unidentifiable in seismic data and a depth-dependent thinning of the crust driven by localized lower crust ductile flow.

  15. Childhood urolithiasis in North-Western Libya

    Directory of Open Access Journals (Sweden)

    M Ben Halim

    2012-01-01

    Full Text Available The study reviews causes of urolithiasis and its manifestations in North-West (NW Libya. Libyan childhood urolithiasis accounted for 3.6% of nephrology out-patient work load. There were 59 children with urolithiasis, including 34 boys and 25 girls with a mean age of 2.8 ± 2.42 years. Urolithiasis was more common among younger age groups (P = 0.001 and in boys with primary oxaluria and infective etiology. The causes of urolithiasis included metabolic stones in 64%, infective in 26%, and it was idiopathic in 10%. Overall, family history of renal stone disease was elicited in 59%; it was 92% in patients with primary oxaluria. The main presenting features were abdominal pain (27%, gross hematuria (22%, associated urinary tract infection (UTI; 24%, and stone release in 19%. Stone location was bilateral in 64%, multiple in 68%, and in the upper tract in 93% (P = 0.05. Important complications encountered included chronic renal failure (13%, hydronephrosis (34%, systemic hypertension (8%, and rickets in 17%. Calcium oxalate was the most prominent constituent, seen in 41% of the calculi, followed by struvite (21%, uric acid (10%, carbapatite (7%, and cystine (3.5%. Diagnostically helpful findings were family history, age at presentation, UTI by urease producing organisms, rickets, imaging and chemical analysis of calculi. Early detection and prompt treatment helps in preventing long-term sequelae in patients with urolithiasis.

  16. Hazardous chemicals in marine mammals from the western North Pacific

    International Nuclear Information System (INIS)

    Marine mammals have long-term life and occupy the highest ecological niche in the marine ecosystem. Thus, higher concentration of hazardous chemicals are expected in marine mammals. In the present study, we review contamination of organochlorine compounds (DDTs, PCBs, HCHs, etc.), heavy metals (Hg, Cd, Pb, etc.) and butyltin (TBT, DBT and MBT) in marine mammals collected from the western North Pacific, and discuss the worldwide contamination of these chemicals

  17. A magmatic probe of dynamic topography beneath western North America

    Science.gov (United States)

    Klöcking, M.; White, N. J.; Maclennan, J.

    2014-12-01

    A region centered on the Yellowstone hotspot and encompassing the Colorado Plateau sits at an elevation 2 km higher than the cratonic North America. This difference broadly coincides with tomographically observed variations in lithospheric thickness: ~120 km beneath western North America, ~240 km beneath the craton. Thermochronology of the Grand Canyon area, sedimentary flux to the Gulf of Mexico, and river profile inversion all suggest that regional uplift occurred in at least two separate stages. High resolution seismic tomographic models, using USArray data, have identified a ring of low velocity material beneath the edges of the Colorado Plateau. Magmatism coincides with these low velocity zones and shows distinct phases: an overall increase in volume around 40 Ma and a change from lithospheric to asthenospheric signatures around 5 Ma. Volcanism is also observed to migrate north-east with time. Here, we attempt to integrate these different observations with lithospheric thickness. A dynamic topography model of progressive lithospheric erosion over a hot mantle plume might account for uplift as well as the temporal and spatial distribution of magmatism across western North America. Thinning of the lithosphere around the edges of the Colorado Plateau in combination with the hotter mantle potential temperature of a plume could create isostatic and dynamic uplift as well as allowing for melt production. To test this model, we have analysed around 100 samples from volcanic centers across western North America by ICP-MS for rare earth elements (REE). Most of the samples are younger than 5 Ma, and all of them have previously been analysed by XRF. Using trace element ratios such as La/Yb and Nb/Y we assess depth of melting and melt fraction, respectively. In addition, we use REE inversion modelling to estimate melt fractions as a function of depth and temperature of melting. The results are compared to existing constraints on lithospheric thickness and mantle potential

  18. Summertime Subtropical Countercurrent on isopycnals in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Circulations on isopycnals (σrθ) in the western North Pacific were investigated by using P-vector method;the data were taken from the U.S. Navy's climatological temperature and salinity dataset (public domain) with 1/2°×1/2° resolution. Results not only show the main circulation systems on isopycnals in the western North Pacific such as the North Equatorial Current (NEC), Kuroshio and Kuroshio Countercurrent, but also reveal the Subtropical Countercurrent (STCC) clearly. In this note we pay attention to discussing the distribution of STCC in summer (in June).The STCC flows eastward along a winding road; on shallow isopycnals, the STCC originates from the area east of Bashi Strait at about 122.5°E; with the isopycnals increasing, the origin and flow core of STCC move to north and east, but the main part of STCC is still between 18° and 23.5°N, i.e.near the Tropic of Cancer. There exists STCC on all isopycnals between the sea surface and 25.8 σθThe current vectors of STCC on isopycnais are shown for the first time, and the distribution of the potential vorticity indicates that STCC is just overlying the southern boundary of the Subtropical Mode Water (STMW).``

  19. North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965―2004, with correlation coeffi-cients of -0.42 and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circula-tion over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical at-mospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

  20. North Pacific sea ice cover, a predictor for the Western North Pacific typhoon frequency?

    Institute of Scientific and Technical Information of China (English)

    FAN Ke

    2007-01-01

    The relationship between the sea ice cover in the North Pacific and the typhoon frequency has been studied in this paper. It follows that the index for the sea ice cover in the North Pacific (ISA) both in December-January-February (DJF) and in March-April-May (MAM) is negatively correlated with annual typhoon number over the western North Pacific (TNWNP) during 1965-2004, with correlation coefficients of -0.42 and -0.49 respectively (above 99% significant level). Large sea ice cover in the North Pacific tends to decrease TNWNP. Positive ISA (MAM) is associated with the tropical circulation and SST anomalies in the North Pacific, which may lead to unfavorable dynamic and thermal conditions for typhoon genesis over WNP from June to October (JJASO). The variability of the atmospheric circulation over the North Pacific, associated with the ISA anomaly in MAM is connected to the tropical atmospheric circulation variability in MAM via the teleconnection wave train. Besides, as the tropical circulation has strong seasonal persistency from the MAM to JJASO, thus, the ISA in MAM-related variability of the tropical atmospheric circulation as well as the SST can affect the typhoon activity over the western North Pacific.

  1. Rapid Middle Eocene temperature change in western North America

    Science.gov (United States)

    Methner, Katharina; Mulch, Andreas; Fiebig, Jens; Wacker, Ulrike; Gerdes, Axel; Graham, Stephan A.; Chamberlain, C. Page

    2016-09-01

    Eocene hyperthermals are among the most enigmatic phenomena of Cenozoic climate dynamics. These hyperthermals represent temperature extremes superimposed on an already warm Eocene climate and dramatically affected the marine and terrestrial biosphere, yet our knowledge of temperature and rainfall in continental interiors is still rather limited. We present stable isotope (δ18O) and clumped isotope temperature (Δ47) records from a middle Eocene (41 to 40 Ma) high-elevation mammal fossil locality in the North American continental interior (Montana, USA). Δ47 paleotemperatures of soil carbonates delineate a rapid +9/-11 °C temperature excursion in the paleosol record. Δ47 temperatures progressively increase from 23 °C ± 3 °C to peak temperatures of 32 °C ± 3 °C and subsequently drop by 11 °C. This hyperthermal event in the middle Eocene is accompanied by low δ18O values and reduced pedogenic carbonate concentrations in paleosols. Based on laser ablation U/Pb geochronology of paleosol carbonates in combination with magnetostratigraphy, biostratigraphy, stable isotope, and Δ47 evidence, we suggest that this pronounced warming event reflects the Middle Eocene Climatic Optimum (MECO) in western North America. The terrestrial expression of northern hemisphere MECO in western North America appears to be characterized by warmer and wetter (sub-humid) conditions, compared to the post-MECO phase. Large and rapid shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes, indicating the profound impact of the MECO on atmospheric circulation and rainfall patterns in the western North American continental interior during this transient warming event.

  2. Seasonal prediction of lightning activity in North Western Venezuela: Large-scale versus local drivers

    Science.gov (United States)

    Muñoz, Á. G.; Díaz-Lobatón, J.; Chourio, X.; Stock, M. J.

    2016-05-01

    The Lake Maracaibo Basin in North Western Venezuela has the highest annual lightning rate of any place in the world (~ 200 fl km- 2 yr- 1), whose electrical discharges occasionally impact human and animal lives (e.g., cattle) and frequently affect economic activities like oil and natural gas exploitation. Lightning activity is so common in this region that it has a proper name: Catatumbo Lightning (plural). Although short-term lightning forecasts are now common in different parts of the world, to the best of the authors' knowledge, seasonal prediction of lightning activity is still non-existent. This research discusses the relative role of both large-scale and local climate drivers as modulators of lightning activity in the region, and presents a formal predictability study at seasonal scale. Analysis of the Catatumbo Lightning Regional Mode, defined in terms of the second Empirical Orthogonal Function of monthly Lightning Imaging Sensor (LIS-TRMM) and Optical Transient Detector (OTD) satellite data for North Western South America, permits the identification of potential predictors at seasonal scale via a Canonical Correlation Analysis. Lightning activity in North Western Venezuela responds to well defined sea-surface temperature patterns (e.g., El Niño-Southern Oscillation, Atlantic Meridional Mode) and changes in the low-level meridional wind field that are associated with the Inter-Tropical Convergence Zone migrations, the Caribbean Low Level Jet and tropical cyclone activity, but it is also linked to local drivers like convection triggered by the topographic configuration and the effect of the Maracaibo Basin Nocturnal Low Level Jet. The analysis indicates that at seasonal scale the relative contribution of the large-scale drivers is more important than the local (basin-wide) ones, due to the synoptic control imposed by the former. Furthermore, meridional CAPE transport at 925 mb is identified as the best potential predictor for lightning activity in the Lake

  3. Palinspastic restoration of NAVDat and its implications for the origins of magmatism in western North America

    Science.gov (United States)

    McQuarrie, N.; Oskin, M.

    2008-12-01

    Simultaneous palinspastic restoration of deformation and volcanism illuminates relationships between magmatism and tectonics in western North America. Using ArcGIS and custom software, we retrodeformed the NAVDat (North American Volcanic Database, navdat.geongrid.org) using the western North America reconstruction of McQuarrie and Wernicke (2005). We compare this data to strain rates calculated over a 50 km-grid forward-deformed from 36 Ma to present. With the deformed grid and palinspastically restored volcanic dataset we quantitatively compare rates of magmatism and deformation and evaluate the age, location, and migration of Cenozoic volcanic arcs. These relationships are shown in a series of palinspastic maps as well as an animation highlighting migrating extension and volcanism with time. We group western North America into 8 different regions with distinct relationships between strain and volcanism. In the northern Basin and Range, southern Arizona and Rio Grande rift areas, a peak in andesitic compositions reflects arc volcanism that preceded significant extension by 5-10 m.y. In the northern Basin and Range, southwestward migration of volcanism in conjunction with westward expansion of the continental margin strongly supports the contention that extension was driven by slab rollback. Southern Arizona and the Colorado River extensional corridor (CEC) have a remarkably similar migration of extension and volcanism that occurred ~10 m.y. later than in the northern Basin and Range. The migration of volcanism from southern Arizona to the CEC and Mojave Desert has been argued to reflect northwestward migration of the volcanic arc from 30 to 15 Ma. However, we note that by 20 Ma both the CEC and the Mojave region directly overlie the slab window in the Farallon plate. In this region extension peaks with or immediately after volcanism and suggests thermal failure of the lithosphere above a growing slab window. At the latitude of Death Valley there is a strong

  4. North-South precipitation patterns in western North America on interannual-to-decadal timescales

    Science.gov (United States)

    Dettinger, M.D.; Cayan, D.R.; Diaz, Henry F.; Meko, D.M.

    1998-01-01

    The overall amount of precipitation deposited along the West Coast and western cordillera of North America from 25??to 55??N varies from year to year, and superimposed on this domain-average variability are varying north-south contrasts on timescales from at least interannual to interdecadal. In order to better understand the north-south precipitation contrasts, their interannual and decadal variations are studied in terms of how much they affect overall precipitation amounts and how they are related to large-scale climatic patterns. Spatial empirical orthogonal functions (EOFs) and spatial moments (domain average, central latitude, and latitudinal spread) of zonally averaged precipitation anomalies along the westernmost parts of North America are analyzed, and each is correlated with global sea level pressure (SLP) and sea surface temperature series, on interannual (defined here as 3-7 yr) and decadal (>7 yr) timescales. The interannual band considered here corresponds to timescales that are particularly strong in tropical climate variations and thus is expected to contain much precipitation variability that is related to El Nino-Southern Oscillation; the decadal scale is defined so as to capture the whole range of long-term climatic variations affecting western North America. Zonal EOFs of the interannual and decadal filtered versions of the zonal-precipitation series are remarkably similar. At both timescales, two leading EOFs describe 1) a north-south seesaw of precipitation pivoting near 40??N and 2) variations in precipitation near 40??N, respectively. The amount of overall precipitation variability is only about 10% of the mean and is largely determined by precipitation variations around 40??-45??N and most consistently influenced by nearby circulation patterns; in this sense, domain-average precipitation is closely related to the second EOF. The central latitude and latitudinal spread of precipitation distributions are strongly influenced by precipitation

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

    Science.gov (United States)

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

    2015-03-01

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

  6. THERMAL VARIATIONS IN OCTOBER 2013 IN NORTH-WESTERN ROMANIA

    Directory of Open Access Journals (Sweden)

    TUDOSE T.

    2014-03-01

    Full Text Available The present analysis refers two weather situations in October 2013 in north-western Romania, represented by a period of cold weather in the first part of the month, and, respectively, a warm period in the last decade of the month. The cold wave produced minimum daily temperatures ranging between -6.4 and -1.9°C, in the lower areas, while in the mountainous region they were between -9.4 and -7.2°C. These values are by 0.2 to 5.6°C lower than the absolute daily minimum temperatures registered between 1961-2012 period. Positive deviations from the maximum daily absolute temperatures up to 4.0°C were recorded in the warm period at the end of the month. The data base used in the study was made up of minimum and maximum daily temperatures for the periods 3-8 and 22-30 October 2013, registered at 14 meteorological stations situated in north-western Romania. Other data used were the air temperature at standard isobaric levels of 850, 700 and 500 hPa, in the period 1973-2013. Synoptic reanalysis maps for the period 1961-2013 were also used.

  7. Conservation of native Pacific trout diversity in western North America

    Science.gov (United States)

    Penaluna, Brooke E.; Abadía-Cardoso, Alicia; Dunham, Jason; García de León, Francisco J; Gresswell, Robert E.; Luna, Arturo Ruiz; Taylor, Eric B.; Shepard, Bradley B.; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Bestgen, Kevin R.; Rogers, Kevin H.; Escalante, Marco A; Keeley, Ernest R; Temple, Gabriel; Williams, Jack E.; Matthews, Kathleen; Pierce, Ron; Mayden, Richard L.; Kovach, Ryan; Garza, John Carlos; Fausch, Kurt D.

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges. Research in recent decades has led to the revision of many hypotheses concerning the origin and diversification of Pacific trout throughout their range. Although there has been significant success at addressing past threats to Pacific trout, contemporary and future threats represented by nonnative species, land and water use activities, and climate change pose challenges and uncertainties. Ultimately, conservation of Pacific trout depends on how well these issues are understood and addressed, and on solutions that allow these species to coexist with a growing scope of human influences.

  8. The Norwegian Danish Basin: A key to understanding the Cenozoic in the eastern North Sea

    Science.gov (United States)

    Rasmussen, Thomas L.; Clausen, Ole R.; Andresen, Katrine J.; Goledowski, Bartosz

    2015-04-01

    -level changes and sourced from the Scandinavian hinterland. 3D-Wheeler diagrams have been used for recognizing spatial elements with periods of deposition and non-deposition. Overall, this study thus contributes significantly to a better understanding of the Cenozoic evolution, the position of potential reservoirs and the debate of climate versus tectonics. References: Michelsen, O., M. Danielsen, C. Heilmann-Clausen, H. Jordt, G. V. Laursen and E. Thomsen, Eds. (1995). Occurrence of major sequence stratigraphic boundaries in relation to basin development in Cenozoic deposits of the southeastern North Sea. Sequence Stratigraphy: Advances and Applications for Exploration and Producing in North West Europe vol 5. Amsterdam, Elsevier. Michelsen, O., E. Thomsen, M. Danielsen, C. Heilmann-Clausen, H. Jordt and G. V. Laursen (1998). Cenozoic sequence stratigraphy in the eastern North Sea. Mesozoic-Cenozoic Sequence Stratigraphy of Western European Basins. P. C. de Graciansky, T. Jacquin and P. R. Vail, Society of Economic Palaeontolgists and Mineralogists Special Publication 60. 60: 91-118.

  9. Exploitation Contradictions Concerning Multi-Energy Resources among Coal, Gas, Oil, and Uranium: A Case Study in the Ordos Basin (Western North China Craton and Southern Side of Yinshan Mountains)

    OpenAIRE

    Xiaowei Feng; Nong Zhang; Xiaoting Chen; Lianyuan Gong; Chuangxin Lv; Yu Guo

    2016-01-01

    The particular “rich coal, meager oil, and deficient gas” energy structure of China determines its high degree of dependence on coal resources. After over 100 years of high-intensity mining activities in Northeast China, East Region, and the Southern Region, coal mining in these areas is facing a series of serious problems, which force China’s energy exploitation map to be rewritten. New energy bases will move to the western and northern regions in the next few years. However, overlapping phe...

  10. North Tropical Atlantic influence on western Amazon fire season variability

    Science.gov (United States)

    Fernandes, Katia; Baethgen, Walter; Bernardes, Sergio; DeFries, Ruth; DeWitt, David G.; Goddard, Lisa; Lavado, Waldo; Lee, Dong Eun; Padoch, Christine; Pinedo-Vasquez, Miguel; Uriarte, Maria

    2011-06-01

    The prevailing wet climate in the western Amazon is not favorable to the natural occurrence of fires. Nevertheless, the current process of clearing of humid forests for agriculture and cattle ranching has increased the vulnerability of the region to the spread of fires. Using meteorological stations precipitation and the Moderate Resolution Spectroradiometer (MODIS) Active-Fires (AF) during 2000-2009, we show that fire anomalies vary closely with July-August-September (JAS) precipitation variability as measured by the Standardized Precipitation Index (SPI). The precipitation variability is, in turn, greatly determined by sea surface temperature (SST) anomalies in the North Tropical Atlantic (NTA). We develop a linear regression model to relate local fire activity to an index of the NTA-SST. By using seasonal forecasts of SST from a coupled model, we are able to predict anomalous JAS fire activity as early as April. We applied the method to predict the severe 2010 JAS season, which indicated strongly positive seasonal fire anomalies within the 95% prediction confidence intervals in most western Amazon. The spatial distribution of predicted SPI was also in accordance with observed precipitation anomalies. This three months lead time precipitation and fire prediction product in the western Amazon could help local decision makers to establish an early warning systems or other appropriate course of action before the fire season begins.

  11. The Mesozoic rift basins of eastern North America: Potential reservoir or Explorationist's folly

    Energy Technology Data Exchange (ETDEWEB)

    Pyron, A.

    1991-08-01

    Mesozoic rift basins are found on the East Coast of North America from Georgia to Nova Scotia. The basins formed as a result of extensional activity associated with the breakup of Pangaea. The internal geometry of the basins includes a depositional sequence ranging from coarse fanglomerates to fine-grained siltstones and argillites. Since these Mesozoic rift basins were first studied, they have not been considered to be likely spots for hydrocarbon accumulations. Recently, geologists have reconsidered these Mesozoic basins and have developed a more synergistic approach that suggests that many of these rift basins might be suitable targets for exploration. By analogy, these Mesozoic basins are correlative to similar basins in northwestern Africa, where significant reserved of oil and natural gas have been developed. The similarity between the productive basins in northwestern Africa and the Mesozoic basins of North America and their proximity to major markets provides sufficient rationale to further investigate these basins.

  12. Snow cover trend and hydrological characteristics of the Astore River basin (Western Himalayas) and its comparison to the Hunza basin (Karakoram region).

    Science.gov (United States)

    Tahir, Adnan Ahmad; Chevallier, Pierre; Arnaud, Yves; Ashraf, Muhammad; Bhatti, Muhammad Tousif

    2015-02-01

    A large proportion of Pakistan's irrigation water supply is taken from the Upper Indus River Basin (UIB) in the Himalaya-Karakoram-Hindukush range. More than half of the annual flow in the UIB is contributed by five of its snow and glacier-fed sub-basins including the Astore (Western Himalaya - south latitude of the UIB) and Hunza (Central Karakoram - north latitude of the UIB) River basins. Studying the snow cover, its spatio-temporal change and the hydrological response of these sub-basins is important so as to better manage water resources. This paper compares new data from the Astore River basin (mean catchment elevation, 4100 m above sea level; m asl afterwards), obtained using MODIS satellite snow cover images, with data from a previously-studied high-altitude basin, the Hunza (mean catchment elevation, 4650 m asl). The hydrological regime of this sub-catchment was analyzed using the hydrological and climate data available at different altitudes from the basin area. The results suggest that the UIB is a region undergoing a stable or slightly increasing trend of snow cover in the southern (Western Himalayas) and northern (Central Karakoram) parts. Discharge from the UIB is a combination of snow and glacier melt with rainfall-runoff at southern part, but snow and glacier melt are dominant at the northern part of the catchment. Similar snow cover trends (stable or slightly increasing) but different river flow trends (increasing in Astore and decreasing in Hunza) suggest a sub-catchment level study of the UIB to understand thoroughly its hydrological behavior for better flood forecasting and water resources management.

  13. Western Gas Sands Project. Quarterly Basin Activities Report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H

    1979-01-31

    This report is a summation of 3 months' drilling and testing activities in the four primary WGSP study areas: Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin. The monitoring of basin activities is part of resource assessment. (DLC)

  14. Western Gas Sands Project Quarterly Basin Activities Report

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, C H

    1979-04-30

    This quarterly basin activities report is a summation of three months drilling and testing activities in the Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin. Detailed information is given for each study area for the first quarter of 1979.

  15. Petrographically deduced triassic climate for the Deep River Basin, eastern piedmont of North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    McCarn, S.T.; Mansfield, C.F.

    1985-01-01

    A petrographic comparison of Triassic, fluvial sandstones from the Deep River Basin in the eastern piedmont of North Carolina with nearby Holocene stream sands (1) indicates that he Triassic climate was more arid than today's and (2) distinguishes an eastern, more plutonic terrane from a western, more metamorphic source terrane. The paleoclimatic interpretation is based on differences in framework composition between modern and ancient sands of the same grain size, derived from the same rock type, transported similar distances and deposited in similar settings. The Triassic sandstones contain more lithic-fragments but less quartz than otherwise equivalent, modern sand in the Deep River Basin. Feldspar content is more complex, controlled by both source-rock composition and climate. Sand from the more plutonic terrane contains more feldspar and plutonic lithic-fragments than sand from the more metamorphic terrane, which contains more quartz and metamorphic lithic-fragments. This petrographic interpretation of the Triassic sandstones along with the presence of coal, limestone, chert and caliche in the middle of the section suggests that the Triassic climate was cyclic, changing from arid to humid and back to arid. Plate-tectonic reconstructions place the Deep River Basin between the Triassic equator and Tropic of cancer, where the easterly trade winds would predominate. Therefore, the arid portions of the cycle could have been due to a periodic, orographic, rain shadow formed as the result of intermittent movement along the Jonesboro Fault, creating a highland area east of the Deep River Basin.

  16. Neogene dinocyst zonation for the eastern North Sea Basin, Denmark

    DEFF Research Database (Denmark)

    Dybkjær, Karen; Piasecki, Stefan

    2010-01-01

    A dinocyst zonation for the Neogene succession in the eastern part of the North Sea Basin (Denmark) is presented. The zonation is based on an extensive database comprising data from more than fifty onshore and offshore boreholes and about twenty five outcrops. Most of the nineteen dinocyst zones...... method allowed the previous last occurrence of Cordosphaeridium cantharellus (one of the zonal index fossils) dated as between 17.95 My and 19.5 My in previous studies, to be assigned a new dating of 18.4 My. The timespan of the zones range from 2.6 My for the Amiculospharea umbraculum Zone to 0.4 My for...

  17. Evidence of late Quaternary wet/dry climate episodes derived from paleoclimatic proxy data recovered from the paleoenvironmental record of the Great Basin of western North America: Paleobotanical studies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    Through the integration of several avenues of paleoclimatic proxy data, the authors intend to arrive a definite conclusions regarding the frequency of periods of wetter climate, and to drive information regarding the magnitudes of these episodes, rates of their onset and demise, and the climatic conditions under which wetter climate can occur. These will in turn lead to rough estimates of: (1) the amounts of rainfall available for recharge during past periods of effectively wetter climate; and (2) the durations and spacing of such events that provide an indication of the amount of time that the area was subjected to these inputs. To accomplish these goals the paleobotanical record over a broad region is being examined to identify periods of greater effective precipitation. Although the project focus is on a region a of about 200 km around Yucca Mountain, they have collected data in other areas of the Great Basin in order to be able to identify large-scale climatic patterns. Once identified and described these climatic patterns can be separated from purely local climatic phenomena that might hinder the understanding of the Pliestocene climates of southern Nevada and the Yucca Mountain area in particular.

  18. Evidence of late Quaternary wet/dry climate episodes derived from paleoclimatic proxy data recovered from the paleoenvironmental record of the Great Basin of western North America: Paleobotanical studies

    International Nuclear Information System (INIS)

    Through the integration of several avenues of paleoclimatic proxy data, the authors intend to arrive a definite conclusions regarding the frequency of periods of wetter climate, and to drive information regarding the magnitudes of these episodes, rates of their onset and demise, and the climatic conditions under which wetter climate can occur. These will in turn lead to rough estimates of: (1) the amounts of rainfall available for recharge during past periods of effectively wetter climate; and (2) the durations and spacing of such events that provide an indication of the amount of time that the area was subjected to these inputs. To accomplish these goals the paleobotanical record over a broad region is being examined to identify periods of greater effective precipitation. Although the project focus is on a region a of about 200 km around Yucca Mountain, they have collected data in other areas of the Great Basin in order to be able to identify large-scale climatic patterns. Once identified and described these climatic patterns can be separated from purely local climatic phenomena that might hinder the understanding of the Pliestocene climates of southern Nevada and the Yucca Mountain area in particular

  19. Risk assessment for yellow fever in western and North-Western provinces of Zambia

    Directory of Open Access Journals (Sweden)

    Olusegun A Babaniyi

    2015-01-01

    Full Text Available Background: North-Western and Western provinces of Zambia were reclassified as low-risk areas for yellow fever (YF. However, the current potential for YF transmission in these areas is unclear. Aims: To determine the current potential risk of YF infection. Setting and Design: A cross sectional study was conducted in North-Western and Western provinces of Zambia. Materials and Methods: Samples were tested for both YF virus-specific IgG and IgM antibodies by the ELISA and YF virus confirmation was done using Plaque Reduction Neutralization Test. The samples were also tested for IgG and IgM antibodies against other flaviviruses. Results: Out of the 3625 respondents who participated in the survey, 46.7% were males and 9.4% were aged less than 5 years. Overall, 58.1% of the participants slept under an impregnated insecticide-treated net and 20.6% reported indoor residual spraying of insecticides. A total of 616 (17.0% samples were presumptive YF positive. The prevalence for YF was 0.3% for long-term infection and 0.2% for recent YF infection. None of the YF confirmed cases had received YF vaccine. Prevalence rates for other flaviviruses were 149 (4.1% for Dengue, 370 (10.2% for West Nile and 217 (6.0% for Zika. Conclusion: There is evidence of past and recent infection of YF in both provinces. Hence, they are at a low risk for YF infection. Yellow fever vaccination should be included in the EPI program in the two provinces and strengthen surveillance with laboratory confirmation.

  20. Using lake sediment records to reconstruct bark beetle disturbances in western North America

    Directory of Open Access Journals (Sweden)

    Jesse Lee Morris

    2013-12-01

    Full Text Available The recent outbreak of native bark beetles in western North America is unprecedented in severity and scale, at least during the historical period. The aim of this work is to develop a proxy-based methodology to understand how bark beetle disturbances are recorded in lake sediments. Three hypotheses are tested to determine how the ecological impacts of severe spruce beetle (Dendroctonus rufipennis disturbances are recorded following mortality of Engelmann spruce (Picea engelmannii. Outbreaks are hypothesized to: (1 decrease the ratio of spruce to fir pollen; (2 increase soil erosion and mobilize terrestrial C; and (3 leach foliar N, enhancing algal productivity. To test these hypotheses, sediment cores from spruce beetle-affected basins were analyzed for pollen, insect remains, organic and minerogenic content, and isotopic and elemental concentrations. The dataset was tested statistically using generalized linear mixed models (GLMMs to determine if the response variables differed significantly between outbreak and non-outbreak periods. 

  1. Paleomagnetic Study of the Devonian Reef Complexes of the Canning Basin, Western Australia

    Science.gov (United States)

    Yan, M.; Tohver, E.; Cawood, P. A.; Kirschvink, J.; Peek, S.; Playton, T.; Hocking, R.; Haines, P.; Montgomery, P.

    2008-12-01

    The reef systems in the Canning Basin, Western Australia perhaps are the best exposed and least deformed examples of ancient reef systems known in the world. The recently commenced multi-disciplinary research project in the Devonian reef complex of the Canning Basin is a broad investigation of the depositional history of a carbonate platform using paleomagnetic, stable isotope geochemistry (inorganic and organic), sedimentology, and biostratigraphy. By focusing on the world-class exposures in the Canning Basin, this project seeks to provide a global stratigraphic reference frame for key intervals in life history such as the Frasnian-Fammenian mass extinction event, as well as providing a useful analogue for resource models of other carbonate reef systems elsewhere in the world. This reference frame will consist of a high resolution magnetostratigraphic profile to supplement the presently-sparse Global Polarity Timescale (GPTS) for the Devonian, as well as a chemostratigraphic profile (chiefly carbon isotopes) to identify possible shifts in the global carbon budget associated with biotic crises and/or climate change. Additional goals include identification of the conditions leading up to, and possible causes of the mass extinction event, and testing for a possible mid-Paleozoic episode of True Polar Wander. We report here on a paleomagnetic study of two magnetostratigraphic sections in the Canning Basin to address the goals mentioned above. Paleomagnetic samples have been drilled on the Late Frasnian limestones in the north of the Windjana Gorge National Park, with a total number of 400 core samples. So far preliminary paleomagnetic analysis on pilot samples reveals two characteristic remanent components. One component has a blocking temperatures less than 400 degree Celsius, probably a component of secondary overprint; another component has a blocking temperature around 580 and around 680 degree Celsius, indicating the presence of magnetite and hematite

  2. Terrane Stations: intra-oceanic subduction assembled western North America

    Science.gov (United States)

    Sigloch, K.; Mihalynuk, M. G.

    2012-12-01

    The western quarter of North America consists of accreted terranes, crustal blocks that were added to the margin in a series of collisions over the past 200 million years - but why? The most widely accepted explanation posits a scenario analogous to Andean subduction, with these terranes conveyed to the continental margin while the oceanic Farallon plate subducted under it. Yet purely Andean-style subduction under North America is questionable as a terrane delivery mechanism, since no comparable accretion sequence took place along the South American margin, and since North American terranes are of very varied provenance. We consider this geological question directly related to a geodynamical one: Why has it been so difficult to reconcile - even on the largest scale - the geometries and locations of slabs in the lower-mantle, as imaged by seismic tomography, with Cretaceous plate reconstructions of the North American west coast (unless anomalous mantle rheology or ad hoc shifts of absolute reference frame are invoked)? This problem was recognized soon after the discovery of the massive, lower-mantle "Farallon slabs" by Grand (1994), but has recently been aggravated by the discovery of additional, more westerly deep slabs (Sigloch et al. 2008), thanks to USArray. Not all of these slabs can be Farallon, unless very non-vertical and/or uneven slab sinking behavior is allowed for. As a joint solution, we offer a radical reinterpretation of paleogeography and test it quantitatively: The seas west of Cretaceous North America must have resembled today's western Pacific. The Farallon and two more plates subducted into the intra-oceanic trenches of a vast archipelago in the eastern Panthalassa (proto-Pacific) ocean, both from the east and the west. The trenches remained stationary throughout much of Jurassic and Cretaceous times, depositing the massive, near-vertical slab walls imaged in the lower mantle today. On their overriding plates, island arcs and subduction complexes

  3. The Permian basin geology in the north of Uruguay.Sedimentology exam about the uranium signs

    International Nuclear Information System (INIS)

    The basin is located in the Precambrian insular shelf limited to the North. East and South. The North (Brazil) and south (Uruguay) edge are constituted by the insular shelf ancient nucleus which dates from 2000 million years.

  4. Palm harvest impacts in north-western South America

    DEFF Research Database (Denmark)

    Balslev, Henrik

    2011-01-01

    Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants...... in tropical American forests. This paper introduces a cross-disciplinary study of the effects of harvesting palm products from the tropical forests in north-western South America. The size of the resource is estimated through palm community studies in the different forest formations that determines the number...... for subsistence purposes Quantitative ethno-botanical research in different forest types have identified thousands of different ways of using palms for food, construction, tool-making, etc. Although most palms are used by the person harvesting them, many are sold on local markets as fruits, fiber, tools...

  5. The Isotopic History of Western North American Grasslands

    Science.gov (United States)

    Crowley, B. E.; Koch, P. L.

    2007-12-01

    Over the last 20 years, researchers have detected a rise in carbon isotope values of fossil mammals, paleosol minerals, and organic substrates roughly 6 to 8 Ma, which indicates an increase in the relative abundance of C4 grass at localities around the world. Prior research has shown that this increase in C4 abundance did not occur in cool high latitude regions, nor did it occur at sites around the Mediterranean. Similarly, modern California and Nevada do not support native C4 grasses. These states have a water regime similar to the Mediterranean region, with hot and dry summers, and most precipitation occurring during the cool winter months. Because the amount of C4 grass in North American ecosystems correlates positively with growing season temperature, it is not surprising that these western states, which have a winter growing season, do not support C4 plants. This does not necessarily imply, however, that C4 plants have never been favored in these western states. We used the carbon isotope composition of fossil ungulate tooth enamel as a proxy for C4 plant abundance in California and Nevada from 18 Ma to the present. Our carbon isotope data suggest that whereas there are very few native C4 species living in California or Nevada today, C4 plants may have been present in the region as early as the Late Miocene. Furthermore, there is an indication that C4 plants may have increased in abundance in the region during Pleistocene glacial periods.

  6. Widespread triploidy in Western North American aspen (Populus tremuloides).

    Science.gov (United States)

    Mock, Karen E; Callahan, Colin M; Islam-Faridi, M Nurul; Shaw, John D; Rai, Hardeep S; Sanderson, Stewart C; Rowe, Carol A; Ryel, Ronald J; Madritch, Michael D; Gardner, Richard S; Wolf, Paul G

    2012-01-01

    We document high rates of triploidy in aspen (Populus tremuloides) across the western USA (up to 69% of genets), and ask whether the incidence of triploidy across the species range corresponds with latitude, glacial history (as has been documented in other species), climate, or regional variance in clone size. Using a combination of microsatellite genotyping, flow cytometry, and cytology, we demonstrate that triploidy is highest in unglaciated, drought-prone regions of North America, where the largest clone sizes have been reported for this species. While we cannot completely rule out a low incidence of undetected aneuploidy, tetraploidy or duplicated loci, our evidence suggests that these phenomena are unlikely to be significant contributors to our observed patterns. We suggest that the distribution of triploid aspen is due to a positive synergy between triploidy and ecological factors driving clonality. Although triploids are expected to have low fertility, they are hypothesized to be an evolutionary link to sexual tetraploidy. Thus, interactions between clonality and polyploidy may be a broadly important component of geographic speciation patterns in perennial plants. Further, cytotypes are expected to show physiological and structural differences which may influence susceptibility to ecological factors such as drought, and we suggest that cytotype may be a significant and previously overlooked factor in recent patterns of high aspen mortality in the southwestern portion of the species range. Finally, triploidy should be carefully considered as a source of variance in genomic and ecological studies of aspen, particularly in western U.S. landscapes.

  7. Hydronomics and terranomics in the Nyando basin of Western Kenya.

    OpenAIRE

    Onyango, Leah; Swallow, Brent; Meinzen-Dick, Ruth

    2005-01-01

    This paper uses the concepts of hydronomics as systems of rules that define water management and terranomics as systems of rules that define land management and explores their linkages in rainfed agriculture and irrigation areas in the Nyando basin. The upper reaches of the basin have experienced a change from large scale commercial farming to more intensive small holder farming while in the flood prone lower reaches of the basin several irrigation schemes have been set up. The basin has a co...

  8. Geologic Mapping to Constrain the Sources and Timing of Fluvial Activity in Western Ladon Basin, Mars

    Science.gov (United States)

    Weitz, C. M.; Wilson, S. A.; Irwin, R. P.; Grant, J. A.

    2016-06-01

    We are mapping two quadrangles in Margaritifer Terra (-15032 and -20032) to define the evolution of the western Ladon basin region as it relates to fluvial/alluvial events occurring on surrounding surfaces.

  9. Palaeoenvironmental changes across the Danian–Selandian boundary in the North Sea Basin

    DEFF Research Database (Denmark)

    Clemmensen, Anne; Thomsen, Erik

    2005-01-01

    southern and eastern part of the North Sea Basin resulted in a huge influx of reworked Cretaceous chalk and an almost complete stop of carbonate production. Finally, later in the early Selandian, in connection to a general sea-level rise and a reduction in the gateway between the North Sea Basin and the...

  10. Petroleum generation and migration in the Ghadames Basin, north Africa: A two-dimensional basin-modeling study

    OpenAIRE

    Underdown, R; Redfern, J

    2008-01-01

    The Ghadames Basin contains important oil- and gas-producing reservoirs distributed across Algeria, Tunisia, and Libya. Regional two-dimensional (2-D) modeling, using data from more than 30 wells, has been undertaken to assess the timing and distribution of hydrocarbon generation in the basin. Four potential petroleum systems have been identified: (1) a Middle-Upper Devonian (Frasnian) and Triassic (Triassic Argilo Greseux lnferieur [TAG-I]) system in the central-western basin; (2) a Lower Si...

  11. The "Teflon basin" myth: Snow-soil interactions in mountain catchments in the western US

    Science.gov (United States)

    Williams, M. W.; Cowie, R. M.

    2015-12-01

    In much of western North America, snow and snowmelt provide the primary means for storage of winter precipitation, effectively transferring water from the relatively wet winter season to the typically dry summers. A common assumption is that high-elevation catchments in the western United States behave like "Teflon basins" and that water released from seasonal storage in snow packs flows directly into streams with little or no interaction with underlying soils. Here I present information from a variety of catchments in the Colorado Front Range on snowmelt/soil interactions using isotopic, geochemical, nutrient and hydrometric data in 2- and 3- component hydrograph separations, along with end-member mixing analysis (EMMA). For most catchments we measured these parameters in weekly precipitation, the seasonal snowpack, snowmelt before contact with the ground, discharge, springs, soil solution, and groundwater. We ran EMMA at the catchment scale for catchments that represent the rain-snow transition zone in the montane forest, the seasonally snow covered sub-alpine to alpine transition zone, and a high-elevation alpine zone near the continental divide. In all catchments three end-members were the source waters for about 95% of discharge. Two end-members were the same in all catchments, snow and groundwater. For the alpine catchment talus springs was the third water source, while rain was the third water source in the two lower-elevation catchments. For all three catchments, soil solution plotted with stream waters along or near a line connecting the snow and groundwater end-members. Thus, for seasonally snow-covered catchments from montane to alpine ecosystems, snowmelt infiltrates underlying soils before snowmelt recharges groundwater reservoirs and contributes to surface flows. Seasonally snow-covered catchments are not Teflon basins. Rather, snowmelt infiltrates soils where solute concentrations are changed by biological and geochemical processes.

  12. Gravity Study of the Queen Valley Pull-Apart Basin, Western Nevada

    Science.gov (United States)

    Black, R. A.; Stockli, D. F.; Christie, M.; Desmond, J.; Kueker, A.; Hadley, M.; Tincher, C.; Casteel, J.

    2005-12-01

    Queen Valley is a pull-apart basin located at the northern end of the White Mountains in western Nevada. It is bounded to the south by the NE-trending Queen Valley fault (QVF) zone and to the north by the EW-trending Coaldale fault (CF) zone. The QVF is a curvilinear feature which transfers strain from the northern termination of the Owens Valley/White Mountain fault zone (OVWMFZ) to the western CF. This study presents new gravity data acquired in the Queen Valley and surrounding ranges in summer 2004 by undergraduates of the University of Kansas and Central Washington University as part of a larger regional tectonic study including detailed structural field mapping and geochronology. Almost 500 new gravity stations were acquired by two field crews as part of a two week field research experience. Standard field procedures were used to tie the station measurements to absolute base stations in Bishop, CA, and station locations and elevations were determined by dual frequency GPS. Data were processed through the traditional suite of latitude, free-air, Bouguer, terrain and isostatic corrections. The data will be processed through the new, standard corrections associated with the National Gravity Database in the near future. Previous regional datasets indicated that the northern Queen Valley had a very thin sediment fill. However, preliminary analyses of the new dataset show that the data resolve several previously unrecognized subsurface features, including paired half-grabens with apparently opposing orientation within the northern Queen Valley. These half-grabens appear to be significantly deeper than previously interpreted from the sparser gravity data. An accommodation structure may decouple these features in mid-basin. A potential transpressional feature at the bend in the valley near the south end of the QVF is also resolved in the data. Shallow seismic reflection and ground-penetrating radar experiments are now being planned to resolve the very near

  13. Review of the Upper Jurassic-Lower Cretaceous stratigraphy in Western Cameros basin, Northern Spain

    DEFF Research Database (Denmark)

    Vidal, Maria del Pilar Clemente

    2010-01-01

    The Upper Jurassic-Lower Cretaceous stratigraphy of the Cameros basin has been reviewed. In Western Cameros the stratigraphic sections are condensed but they have a parallel development with the basin depocentre and the same groups have been identified. The Tera Group consists of two formations: ...

  14. Suggestion of a dynamic model of North China basin-range system

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    It is found from preliminary studies that previous basin-range models have difficulties in explaining the formation of the Mesozoic North-China basin-range system. This work suggests a new model-"tectonic thermal erosion" model, which considers the North China basin of Late Mesozoic and its peripheral ranges as a unified system, identifies relationship between upwelling and lateral spreading of the asthenolith with horizontal movement and deformation of the upper crust in the system, clarifies the effects of underplating erosion on the crustal evolution, and tries to establish an earth-dynamic model of the North China Mesozoic basin-range supported by numerical simulation.

  15. Structural modelling of thrust zones utilizing photogrammetry: Western Champsaur basin, SE France

    Science.gov (United States)

    Totake, Yukitsugu; Butler, Rob; Bond, Clare

    2016-04-01

    Recent advances in photogrammetric technologies allow geoscientists to easily obtain a high-resolution 3D geospatial data across multiple scales, from rock specimen to landscape. Although resolution and accuracy of photogrammetry models are dependent on various factors (a quality of photography, number of overlapping photo images, distance to targets, etc), modern photogrammetry techniques can even provide a comparable data resolution to laser scanning technologies (costs for infrastructures, ease to incorporate these techniques with conventional geological surveys. Photogrammetry techniques have a great potential to enhance performances of geological surveys. We present a workflow for building basin-scale 3D structural models utilizing the ground-based photogrammetry along with field observations. The workflow is applied to model thrust zones in Eocene-Oligocene turbidite sequences called Champsaur Sandstone (Gres du Champsaur) filling an Alpine fore-deep basin, Western Champsaur basin, in southeastern France. The study area is located ca. 20km northeast from Gap, and approximately extends 10 km from east to west and 6 km from north to south. During a 2-week fieldwork, over 9400 photographs were taken at 133 locations by a handheld digital camera from ground, and were georeferenced with a handheld GPS. Photo images were processed within software PhotoScan to build a 3D photogrammetric model. The constructed photogrammetry model was then imported into software Move to map faults and geological layers along with georeferenced field data so that geological cross sections and 3D surfaces are produced. The workflow succeeded to produce a detailed topography and textures of landscape at ~1m resolution, and enabled to characterize thrust systems in the study area at bed-scale resolution. Three-dimensionally characterized architectures of thrust zones at high resolution permit to read structural evolution history and kinematics of thrust faults in multilayered sandstone

  16. Orbital control of the western North Pacific summer monsoon

    Science.gov (United States)

    Wu, Chi-Hua; Chiang, John C. H.; Hsu, Huang-Hsiung; Lee, Shih-Yu

    2016-02-01

    Orbital forcing exerts a strong influence on global monsoon systems, with higher summer insolation leading to stronger summer monsoons in the Northern Hemisphere. However, the associated regional and seasonal changes, particularly the interaction between regional monsoon systems, remain unclear. Simulations using the Community Earth System Model demonstrate that the western North Pacific (WNP) summer monsoon responds to orbital forcing opposite to that of other major Northern Hemisphere monsoon systems. Compared with its current climate state, the simulated WNP monsoon and associated lower-tropospheric trough is absent in the early Holocene when the precession-modulated Northern Hemisphere summer insolation is higher, whereas the summer monsoons in South and East Asia are stronger and shift farther northward. We attribute the weaker WNP monsoon to the stronger diabatic heating of the summer Asian monsoon—in particular over the southern Tibetan Plateau and Maritime Continent—that in turn strengthens the North Pacific subtropical high through atmospheric teleconnections. By contrast, the impact of the midlatitude circulation changes on the WNP monsoon is weaker when the solar insolation is higher. Prior to the present WNP monsoon onset, the upper-tropospheric East Asian jet stream weakens and shifts northward; the monsoon onset is highly affected by the jet-induced high potential vorticity intrusion. In the instance of the extreme perihelion-summer, the WNP monsoon is suppressed despite a stronger midlatitude precursor than present-day, and the midlatitude circulation response to the enhanced South Asian precipitation is considerable. These conditions indicate internal monsoon interactions of an orbital scale, implying a potential mechanistic control of the WNP monsoon.

  17. Nahcolite and halite deposition through time during the saline mineral phase of Eocene Lake Uinta, Piceance Basin, western Colorado

    Science.gov (United States)

    Johnson, Ronald C.; Brownfield, Michael E.

    2013-01-01

    Halite and the sodium bicarbonate mineral nahcolite were deposited during the saline phase of Eocene Lake Uinta in the Piceance Basin, western Colorado. Variations in the area of saline mineral deposition through time were interpreted from studies of core and outcrop. Saline minerals were extensively leached by groundwater, so the original extent of saline deposition was estimated from the distribution of empty vugs and collapse breccias. Vugs and breccias strongly influence groundwater movement, so determining where leaching has occurred is an important consideration for in-situ oil shale extraction methods currently being developed. Lake Uinta formed when two smaller fresh water lakes, one in the Uinta Basin of eastern Utah and the other in the Piceance Basin of western Colorado, expanded and coalesced across the Douglas Creek arch, an area of comparatively low subsidence rates. Salinity increased shortly after this expansion, but saline mineral deposition did not begin until later, after a period of prolonged infilling created broad lake-margin shelves and a comparatively small deep central lake area. These shelves probably played a critical role in brine evolution. A progression from disseminated nahcolite and nahcolite aggregates to bedded nahcolite and ultimately to bedded nahcolite and halite was deposited in this deep lake area during the early stages of saline deposition along with rich oil shale that commonly shows signs of slumping and lateral transport. The area of saline mineral and rich oil shale deposition subsequently expanded, in part due to infilling of the compact deep area, and in part because of an increase in water flow into Lake Uinta, possibly due to outflow from Lake Gosiute to the north. Finally, as Lake Uinta in the Piceance Basin was progressively filled from north to south by volcano-clastic sediment, the saline depocenter was pushed progressively southward, eventually covering much of the areas that had previously been marginal shelves

  18. Bootstrap inversion for Pn wave velocity in North-Western Italy

    Directory of Open Access Journals (Sweden)

    C. Eva

    1997-06-01

    Full Text Available An inversion of Pn arrival times from regional distance earthquakes (180-800 km, recorded by 94 seismic stations operating in North-Western Italy and surrounding areas, was carried out to image lateral variations of P-wave velocity at the crust-mantle boundary, and to estimate the static delay time at each station. The reliability of the obtained results was assessed using both synthetic tests and the bootstrap Monte Carlo resampling technique. Numerical simulations demonstrated the existence of a trade-off between cell velocities and estimated station delay times along the edge of the model. Bootstrap inversions were carried out to determine the standard deviation of velocities and time terms. Low Pn velocity anomalies are detected beneath the outer side of the Alps (-6% and the Western Po plain (-4% in correspondence with two regions of strong crustal thickening and negative Bouguer anomaly. In contrast, high Pn velocities are imaged beneath the inner side of the Alps (+4% indicating the presence of high velocity and density lower crust-upper mantle. The Ligurian sea shows high Pn velocities close to the Ligurian coastlines (+3% and low Pn velocities (-1.5% in the middle of the basin in agreement with the upper mantle velocity structure revealed by seismic refraction profiles.

  19. Influence of the Western Pacific teleconnection pattern on Western North Pacific tropical cyclone activity

    Science.gov (United States)

    Choi, Ki-Seon; Moon, Il-Ju

    2012-09-01

    This study analyzes the characteristics of Western North Pacific (WNP) tropical cyclone (TC) activity and large-scale environments according to the Western Pacific (WP) teleconnection pattern in summer. In the positive WP phase, an anomalous cyclone and an anomalous anticyclone develop in the low and middle latitudes of the East Asia area, respectively. As a result, southeasterlies are reinforced in the northeast area of East Asia (including Korea and Japan), which facilitates the movement of TC to this area, whereas northwesterlies are reinforced in the southwest area of East Asia (including southern China and the Indochina Peninsula) which blocks the movement of TC to that area. Due to the spatial distribution of this reinforced pressure system, TCs that develop during the positive WP phase move and turn more to the northeast of the WNP than TCs which develop during the negative WP phase. The characteristics of this TC activity during the positive WP phase are associated with the upper tropospheric jet being located farther to the northeast. TCs during the negative WP phase mainly move to the west from the Philippines toward southern China and the Indochina Peninsula. Due to the terrain effect caused by the passage of TCs in mainland China, the intensity of TCs during the negative WP phase is weaker than those during the positive WP phase.

  20. Typical basin-fill sequences and basin migration in Yanshan, North China--Response to Mesozoic tectonic transition

    Institute of Scientific and Technical Information of China (English)

    LI; Zhong; LIU; Shaofeng; ZHANG; Jinfang; WANG; Qingchen

    2004-01-01

    Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

  1. Mercury and methylmercury in aquatic sediment across western North America

    Science.gov (United States)

    Fleck, Jacob; Marvin-DiPasquale, Mark C.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; Lutz, Michelle A; Tate, Michael T.; Alpers, Charles N.; Hall, Britt D.; Krabbenhoft, David P.; Eckley, Chris S.

    2016-01-01

    Large-scale assessments are valuable in identifying primary factors controlling total mercury (THg) and monomethyl mercury (MeHg) concentrations, and distribution in aquatic ecosystems. Bed sediment THg and MeHg concentrations were compiled for > 16,000 samples collected from aquatic habitats throughout the West between 1965 and 2013. The influence of aquatic feature type (canals, estuaries, lakes, and streams), and environmental setting (agriculture, forest, open-water, range, wetland, and urban) on THg and MeHg concentrations was examined. THg concentrations were highest in lake (29.3 ± 6.5 μg kg− 1) and canal (28.6 ± 6.9 μg kg− 1) sites, and lowest in stream (20.7 ± 4.6 μg kg− 1) and estuarine (23.6 ± 5.6 μg kg− 1) sites, which was partially a result of differences in grain size related to hydrologic gradients. By environmental setting, open-water (36.8 ± 2.2 μg kg− 1) and forested (32.0 ± 2.7 μg kg− 1) sites generally had the highest THg concentrations, followed by wetland sites (28.9 ± 1.7 μg kg− 1), rangeland (25.5 ± 1.5 μg kg− 1), agriculture (23.4 ± 2.0 μg kg− 1), and urban (22.7 ± 2.1 μg kg− 1) sites. MeHg concentrations also were highest in lakes (0.55 ± 0.05 μg kg− 1) and canals (0.54 ± 0.11 μg kg− 1), but, in contrast to THg, MeHg concentrations were lowest in open-water sites (0.22 ± 0.03 μg kg− 1). The median percent MeHg (relative to THg) for the western region was 0.7%, indicating an overall low methylation efficiency; however, a significant subset of data (n > 100) had percentages that represent elevated methylation efficiency (> 6%). MeHg concentrations were weakly correlated with THg (r2 = 0.25) across western North America. Overall, these results highlight the large spatial variability in sediment THg and MeHg concentrations throughout western North America and underscore the important roles that landscape and land

  2. Spatial variation in biofouling of a unionid mussel (Lampsilis siliquoidea) across the western basin of Lake Erie

    Science.gov (United States)

    Larson, James H.; Evans, Mary; Richardson, William B.; Schaeffer, Jeff; Nelson, John

    2016-01-01

    Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensishas resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability to open and close their shells. Initial expectations for the Great Lakes included extirpation of unionids where they co-occurred with dreissenids, but recently adult and juvenile unionids have been found alive in several apparent refugia. These unionid populations may persist due to reduced dreissenid biofouling in these areas, and/or due to processes that remove biofoulers. For example locations inaccessible to dreissenid veligers may reduce biofouling and habitats with soft substrates may allow unionids to burrow and thus remove dreissenids. We deployed caged unionid mussels (Lampsilis siliquoidea) at 36 sites across the western basin of Lake Erie to assess spatial variation in biofouling and to identify other areas that might promote the persistence or recovery of native unionid mussels. Biofouling ranged from 0.03 – 26.33 g per mussel, reached a maximum in the immediate vicinity of the mouth of the Maumee River, and appeared to primarily consist of dreissenid mussels. A known mussel refugium in the vicinity of a power plant near the mouth of the Maumee actually exhibited very high biofouling rates, suggesting that low dreissenid colonization did not adequately explain unionid survival in this refugium. In contrast, the southern nearshore area of Lake Erie, near another refugium, had very low biofouling. A large stretch of the western basin appeared to have low biofouling rates and muddy substrates, raising the possibility that these open water areas could support remnant and returning populations of unionid mussels. Previous observations of unionid refugia and the occurrence of low biofouling rates in large areas of the western

  3. Storing CO2 under the North Sea Basin - A key solution for combating climate change

    International Nuclear Information System (INIS)

    This report represents the first deliverable of the North Sea Basin Task Force, which Norway and the UK established in November 2005 to work together on issues surrounding the transport and storage of CO2 beneath the North Sea. The North Sea represents the best geological opportunity for storing our CO2 emissions away from the atmosphere for both the UK and Norway

  4. Status of woodland caribou in western north America

    Directory of Open Access Journals (Sweden)

    E. Janet Edmonds

    1991-10-01

    Full Text Available A review of current population size and trends of woodland caribou (Rangifer tarandus caribou in seven jurisdictions in western North America shows a wide range of situations. A total maximum population estimate of woodland caribou west of the Ontario/Manitoba border is 61 090. Of 44 herds or populations described in this review: 14 are stable; two are stable to slightly decreasing; four are decreasing; four are increasing; and 22 are of unknown status. Caribou are classified as a threatened species in Alberta and as an endangered species in Washington/Idaho. The decline of caribou in North America following settlement (Bergerud, 1974 has continued along the southern edge of woodland caribou distribution. Direct loss of habitat to logging, mines and dams continued throughout the I960s, 1970s and 1980s. The secondary effects of these habitat changes, (i.e. increased roads leading to increased hunting and poaching, and increased early succession habitat leading to increased alternate prey/predator densities has led in some cases to the total loss or decreased size of local herds. Three ecotypes of woodland caribou are described and their relative distribution delineated. These ecotypes live under different environmental conditions and require different inventory and management approaches. Woodland caribou herds in northern B.C., Yukon and N.W.T. generally are of good numbers and viable (stable or increasing, and management primarily is directed at regulating human harvest and natural predation to prevent, herd declines. Land use activities such as logging or energy development are not extensive. Managers in southern caribou ranges stress the need for a better understanding of caribou population stability within mixed prey/predator regimes; how habitat changes (eg. through logging affect these regimes; and how to develop effective land use guidelines for resource extraction that can sustian caribou populations and maintain resource industries

  5. Gravity anomalies, crustal structure and rift tectonics at the Konkan and Kerala basins, western continental margin of India

    Indian Academy of Sciences (India)

    Sheena V Dev; M Radhakrishna; Shyam Chand; C Subrahmanyam

    2012-06-01

    Litho-stratigraphic variation of sedimentary units constructed from seismic sections and gravity anomaly in the Konkan and Kerala basins of the western continental margin of India (WCMI) have been used to model processes such as lithospheric rifting mechanism, its strength, and evolution of flank uplift topography that led to the present-day Western Ghats escarpment. Based on the process-oriented approach, two lithospheric models (necking and magmatic underplating) of evolution of the margin were tested. Both, necking and underplating models suggest an effective elastic thickness (Te) of 5 km and 10 km along Konkan and Kerala basins, respectively and a deep level of necking at 20 km at both basins. Model study suggests that the necking model better explains the observed gravity anomalies in the southern part of the WCMI. A synthesis of these results along with the previously published elastic thickness estimates along the WCMI suggests that a low-to-intermediate strength lithosphere and a deeper level of necking explains the observed flank-uplift opography of the Western Ghats. Process-oriented gravity modeling further suggests that the lateral variations in the lithospheric strength, though not very significant, exist from north to south within a distance of 600 km in the Konkan and Kerala basins along the WCMI at the time of rifting. A comparison with previous Te estimates from coherence analysis along the WCMI indicates that the lithospheric strength did not change appreciably since the time of rifting and it is low both onshore and offshore having a range of 5–15 km.

  6. Pu isotopes in the western North Pacific Ocean before the accident at Fukushima Dai-ichi Nuclear Power Station

    Science.gov (United States)

    Yamada, M.; Zheng, J.; Aono, T.

    2011-12-01

    Anthropogenic radionuclides such as Pu-239 (half-life: 24100 yr), Pu-240 (half-life: 6560 yr) and Pu-241 (half-life: 14.325 yr) mainly have been released into the environment as the result of atmospheric nuclear weapons testing. In the North Pacific Ocean, two distinct sources of Pu isotopes can be identified; i.e., the global stratospheric fallout and close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds in the Marshall Islands. The atom ratio of Pu-240/Pu-239 is a powerful fingerprint to identify the sources of Pu in the ocean. The Pu-240/Pu-239 atom ratios in seawater and marine sediment samples collected in the western North Pacific before the accident at Fukushima Dai-ichi Nuclear Power Station will provide useful background data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The atom ratios of Pu-240/Pu-239 in water columns from the Yamato and Tsushima Basins in the Japan Sea were significantly higher than the mean global fallout ratio of 0.18; however, there were no temporal variation of atom ratios during the period from 1984 to 1993 in the Japan Sea. The total Pu-239+240 inventories in the whole water columns were approximately doubled during the period from 1984 to 1993 in the two basins. The atom ratio of Pu-240/Pu-239 in surface water from Sagami Bay, western North Pacific Ocean, was 0.224 and showed no notable variation from the surface to the bottom with the mean atom ratio being 0.234. The atom ratios for the Pacific coast, near the Rokkasho nuclear fuel reprocessing plant, were approximately the same as the 0.224 ratio obtained from Sagami Bay, western North Pacific margin. The atom ratios in the surficial sediments from Sagami Bay ranged from 0.229 to 0.247. The mean atom ratio in the sediment columns in the East China Sea ranged from 0.248 for the Changjiang estuary to 0.268 for the shelf edge. The observed atom ratios were significantly higher than the mean

  7. Climate and flow variation revealed in tree rings of riparian cottonwood, western North Dakota, USA

    Science.gov (United States)

    Friedman, J. M.; Edmondson, J. R.; Meko, D. M.; Touchan, R.; Griffin, E. R.; Zhou, H.

    2014-12-01

    In the western Great Plains, where old upland trees are scarce, rings of riparian trees provide an important opportunity for reconstructing past river flow and climate. We present data from 489 plains cottonwood (Populus deltoides ssp. monilifera) trees along the Little Missouri River in western North Dakota. The trees are in randomly selected flood-plain locations within the North and South units of Theodore Roosevelt National Park. The two sites are separated by 160 river km. The Little Missouri watershed contains foothills but no mountains, and most annual high flows result from snowmelt in March or April. Cores were collected and processed using standard dendrochronological methods. The effect of tree age was removed from the chronology using a single relation for the site as a whole (age-curve standardization), which preserves century-scale variation. Trees were as old as 371 years. Given that cottonwood establishment depends upon channel migration, abundant establishment from 1864-1891 at both sites suggests that one or more large floods occurred prior to this period. At the North Unit, establishment continued at a lower rate during the next century, but upstream at the South Unit, tree establishment was greatly curtailed after the 1800s. Comparison of General Land Office Maps from 1907 to recent satellite imagery confirms that channel migration in the last century was much greater within the North Unit, a difference caused in part by a downstream increase in flood amplification by ice jamming. Ring widths show that even on the flood plain riparian trees were chronically drought stressed. At both sites growth was strongly positively correlated with flow and precipitation and weakly negatively correlated with temperature. Growth was most strongly correlated with flow and precipitation in April-July, which is consistent with dendrometer-band measurements showing growth cessation in August. Whereas cottonwood establishment decreased in the 1900s, ring widths

  8. Urinary stone disease in Kano, North Western Nigeria

    Directory of Open Access Journals (Sweden)

    S A Aji

    2011-01-01

    Full Text Available Background: Urinary stone disease is the third most common affliction of the urinary tract after urinary tract infection and pathologic conditions of the prostate. Although the disease is commoner in the developed countries, the incidence is also increasing in the developing countries. In this study, we sought to determine the pattern and treatment given for patients with urinary stones in our institution. Patients and Method: A 5 year retrospective study of patients treated for urolithiasis was conducted in a Teaching Hospital in North-western Nigeria. The age, sex, clinical presentations, investigations and treatment offered to the patients were reviewed. Results: A total of seventy six patients were treated for urinary stones during the study period. 58(76.3% were males and 18(23.7% females. Majority of patients 39(51.3% presented with loin pain as the main presenting symptom. The diagnosis of stones was by plain abdominal Xray(KUB in 68 patients and abdominal ultrasound scan in 46 cases. Urine culture was positive in 27 patients with E. coli as the predominant organism. All had normal serum calcium, phosphate and uric acid. 56(73.7% patients had stones in the upper urinary tract and 20 (26.3% in the lower urinary tract. Thirty four (44.7% patients were found to have predisposing factors. Most of the patients 50(65.7% were treated by open surgery and 26(34.2% by endoscopic removal/lithotripsy. Conclusion: Urinary stone disease is common in this environment. Majority of the stones are radio-opaque on plain xrays. Significant number of patients had a predisposing factor and majority of the stones were found in the upper tract. Most of the patients were treated by open surgery while a significant number were treated with endoscopic removal/lithotripsy.

  9. Fire Weather Index application in north-western Italy

    Directory of Open Access Journals (Sweden)

    D. Cane

    2008-05-01

    Full Text Available Piedmont region is located in North-Western Italy and is surrounded by the alpine chain and by the Appennines. The region is covered by a wide extension of forests, mainly in its mountain areas (the forests cover 36% of the regional territory. Forested areas are interested by wildfire events. In the period 1997–2005 Piedmont was interested by an average 387 forest fires per year, covering an average 1926 ha of forest per year. Meteorological conditions like long periods without precipitation contribute to create favourable conditions to forest fire development, while the fire propagation is made easier by the foehn winds, frequently interesting the region in winter and spring particularly. The meteorological danger index FWI (Fire Weather Index was developed by Van Wagner (1987 for the Canadian Forestry Service, providing a complete description of the behaviour of the different forest components in response to the changing weather conditions. We applied the FWI to the Piedmont region on warning areas previously defined for fire management purposes. The meteorological data-set is based on the data of the very-dense non-GTS network of weather stations managed by Arpa Piemonte. The thresholds for the definition of a danger scenarios system were defined comparing historical FWI data with fires occurred on a 5 years period. The implementation of a prognostic FWI prediction system is planned for the early 2008, involving the use of good forecasts of weather parameters at the station locations obtained by the Multimodel SuperEnsemble post-processing technique.

  10. Knowledge exchange for climate adaptation planning in western North America

    Science.gov (United States)

    Garfin, Gregg; Orr, Barron

    2015-04-01

    In western North America, the combination of sustained drought, rapid ecosystem changes, and land use changes associated with urban population growth has motivated concern among ecosystem managers about the implications of future climate changes for the landscapes which they manage. Through literature review, surveys, and workshop discussions, we assess the process of moving from concern, to planning, to action, with an emphasis on questions, such as: What are the roles of boundary organizations in facilitating knowledge exchange? Which practices lead to effective interactions between scientists, decision-makers, and knowledge brokers? While there is no "one size fits all" science communication method, the co-production of science and policy by research scientists, science translators, and decision-makers, as co-equals, is a resource intensive, but effective practice for moving adaptation planning forward. Constructive approaches make use of alliances with early adopters and opinion leaders, and make strong communication links between predictions, impacts and solutions. Resource managers need information on the basics of regional climate variability and global climate change, region-specific projections of climate changes and impacts, frank discussion of uncertainties, and opportunities for candid exploration of these topics with peers and subject experts. Research scientists play critical roles in adaptation planning discussions, because they assist resource managers in clarifying the cascade of interactions leading to potential impacts and, importantly, because decision-makers want to hear the information straight from the scientists conducting the research, which bolsters credibility. We find that uncertainty, formerly a topic to avoided, forms the foundation for constructive progress in adaptation planning. Candid exploration of the array of uncertainties, including those due to modeling, institutional, policy and economic factors, with practitioners, science

  11. Early 21st century snow cover state over the western river basins of the Indus River system

    Science.gov (United States)

    Hasson, S.; Lucarini, V.; Khan, M. R.; Petitta, M.; Bolch, T.; Gioli, G.

    2014-10-01

    In this paper we assess the snow cover and its dynamics for the western river basins of the Indus River system (IRS) and their sub-basins located in Afghanistan, China, India and Pakistan for the period 2001-2012. First, we validate the Moderate Resolution Imaging Spectroradiometer (MODIS) daily snow products from Terra (MOD10A1) and Aqua (MYD10A1) against the Landsat Thematic Mapper/Enhanced Thematic Mapper plus (TM/ETM+) data set, and then improve them for clouds by applying a validated non-spectral cloud removal technique. The improved snow product has been analysed on a seasonal and annual basis against different topographic parameters (aspect, elevation and slope). Our results show a decreasing tendency for the annual average snow cover for the westerlies-influenced basins (upper Indus basin (UIB), Astore, Hunza, Shigar and Shyok) and an increasing tendency for the monsoon-influenced basins (Jhelum, Kabul, Swat and Gilgit). Seasonal average snow cover decreases during winter and autumn, and increases during spring and summer, which is consistent with the observed cooling and warming trends during the respective seasons. Sub-basins at relatively higher latitudes/altitudes show higher variability than basins at lower latitudes/middle altitudes. Northeastern and northwestern aspects feature greater snow cover. The mean end-of-summer regional snow line altitude (SLA) zones range from 3000 to 5000 m a.s.l. for all basins. Our analysis provides an indication of a descending end-of-summer regional SLA zone for most of the studied basins, which is significant for the Shyok and Kabul basins, thus indicating a change in their water resources. Such results are consistent with the observed hydro-climatic data, recently collected local perceptions and glacier mass balances for the investigated period within the UIB. Moreover, our analysis shows a significant correlation between winter season snow cover and the North Atlantic Oscillation (NAO) index of the previous autumn

  12. Environmental impact assessment in the pipeline industry. Experiences with the UK north western ethylene pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Ryde, A.

    1997-12-31

    The north western ethylene pipeline is the final link between Shell`s oil and gas fields in the North Sea and its petrochemical complexes in Cheshire. The natural gas from which ethylene is obtained comes from the Brent and central fields in the North Sea. Environmental impacts are discussed in this paper covering topics as follow: Regulatory and legal aspects; environmental assessment during planning and design; environmental control during construction; environmental management during operation; environmental controls at sensitive sites on the north western ethylene pipeline: some examples. 11 refs., 2 figs.

  13. Variability of mineral dust deposition in the western Mediterranean basin and South-East of France

    Directory of Open Access Journals (Sweden)

    J. Vincent

    2015-12-01

    Full Text Available Previous studies have provided some insight into the Saharan dust deposition at a few specific locations from observations over long time periods or intensive field campaigns. However, no assessment of the dust deposition temporal variability in connection with its regional spatial distribution has been achieved so far from network observations over more than one year. To investigate dust deposition dynamics at the regional scale, five automatic deposition collectors named CARAGA ("Collecteur Automatique de Retombées Atmosphériques insolubles à Grande Autonomie" in French have been deployed in the western Mediterranean region during one to three years depending on the station. The sites include, from South to North, Lampedusa Isl., Mallorca Isl., Corsica Isl., Frioul Isl. and Le Casset (South of French Alps. Deposition measurements are performed on a common weekly period at the 5 sites. The mean Saharan dust deposition fluxes are higher close to the North African coasts and decrease following a South to North gradient, with values from 7.4 g m−2 yr−1 in Lampedusa (35°31' N–12°37' E to 1 g m−2 yr−1 in Le Casset (44°59' N–6°28' E. The maximum deposition flux recorded is of 3.2 g m−2 wk−1 in Mallorca with only 2 other events showing more than 1 g m−2 wk−1 in Lampedusa, and a maximum of 0.5 g m−2 wk−1 in Corsica. The maximum value of 2.1 g m−2 yr−1 observed in Corsica in 2013 is much lower than existing records in the area over the 3 previous decades (11–14 g m−2 yr−1. From the 537 available samples, ninety eight major Saharan dust deposition events have been identified in the records between 2011 and 2013. Complementary observations provided by both satellite and air mass trajectories are used to identify the dust provenance areas and the transport pathways from the Sahara to the stations. Despite the large size of African dust plumes detected by satellites, more than eighty percent of the major dust

  14. Variability of aerosol optical properties in the Western Mediterranean Basin

    Directory of Open Access Journals (Sweden)

    M. Pandolfi

    2011-05-01

    Full Text Available Aerosol light scattering, black carbon (BC and particulate matter (PM concentrations were measured at Montseny, a regional background site in the Western Mediterranean Basin (WMB which is part of the European Supersite for Atmospheric Aerosol Research (EUSAAR. Off line analyses of 24 h PM filters collected with Hi-Vol instruments were performed for the determination of the main chemical components of PM. Measurements of BC were used to calculate the light absorption properties of atmospheric particles. Single Scattering Albedo (SSA at 635 nm was estimated starting from aerosol scattering and absorption measurements, while Ångström exponents were calculated by means of the three wavelengths (450 nm, 525 nm, 635 nm aerosol light scattering measurements from Nephelometer. Mean scattering and hemispheric backscattering coefficients (@ 635 nm were 26.8 ± 23.3 Mm−1 and 4.3 ± 2.7 Mm−1, respectively and the mean aerosol absorption coefficient was 2.8 ± 2.2 Mm−1. Mean values of Single Scattering Albedo (SSA and Ångström exponent (calculated from 450 nm to 635 nm at MSY were 0.90 ± 0.05 and 1.2 ± 0.6, respectively. A clear relationship was observed between the PM1/PM10 and PM2.5/PM10 ratios as a function of the calculated Ångström exponents. Mass scattering cross sections for fine mass and sulfate at 635 nm were calculated in 2.8 ± 0.5 m2 g−1 and 11.8 ± 2.2 m2 g−1 respectively, while the mean aerosol absorption cross section was estimated around 10.4 ± 2.0 m2 g−1. The variability in aerosol optical properties in the WMB were largely explained by the origin and ageing of air masses over the measurement site. The sea breeze played an important role in transporting pollutants from the developed WMB coastlines towards inland rural areas, changing the optical properties of aerosols. Aerosol

  15. Variability of aerosol optical properties in the Western Mediterranean Basin

    Directory of Open Access Journals (Sweden)

    M. Pandolfi

    2011-08-01

    Full Text Available Aerosol light scattering, absorption and particulate matter (PM concentrations were measured at Montseny, a regional background site in the Western Mediterranean Basin (WMB which is part of the European Supersite for Atmospheric Aerosol Research (EUSAAR. Off line analyses of 24 h PM filters collected with Hi-Vol instruments were performed for the determination of the main chemical components of PM. Mean scattering and hemispheric backscattering coefficients (@ 635 nm were 26.6±23.2 Mm−1 and 4.3±2.7 Mm−1, respectively and the mean aerosol absorption coefficient (@ 637 nm was 2.8±2.2 Mm−1. Mean values of Single Scattering Albedo (SSA and Ångström exponent (å (calculated from 450 nm to 635 nm at MSY were 0.90±0.05 and 1.3±0.5 respectively. A clear relationship was observed between the PM1/PM10 and PM2.5/PM10 ratios as a function of the calculated Ångström exponents. Mass scattering cross sections (MSC for fine mass and sulfate at 635 nm were 2.8±0.5 m2 g−1 and 11.8±2.2 m2 g−1, respectively, while the mean aerosol absorption cross section (MAC was 10.4±2.0 m2 g−1. The variability in aerosol optical properties in the WMB were largely explained by the origin and ageing of air masses over the measurement site. The MAC values appear dependent of particles aging: similar to the expected absorption cross-section for fresh emissions under Atlantic Advection episodes and higher under aerosol pollution episodes. The analysis of the Ångström exponent as a function of the origin the air masses revealed that polluted winter anticyclonic conditions and summer recirculation scenarios typical of the WMB led to an increase of fine particles in the atmosphere (å = 1.5±0.1 while the aerosol optical properties under Atlantic Advection episodes and Saharan dust outbreaks were clearly

  16. Avalonian crustal controls on basin evolution: implications for the Mesozoic basins of the southern North Sea

    Science.gov (United States)

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

    2015-04-01

    Little is known of the Southern North Sea Basin's (SNSB) Pre-Permian basement due to a lack of outcrop and cores. The nature and structure of the East Avalonian crust and lithosphere remain even less constrained in the absence of deep seismic (refraction) lines. However, various studies have hinted at the importance of the Reactivation of the Early Carboniferous fault network during each consecutive Mesozoic and Cenozoic tectonic phase, demonstrating the key role of weak zones from the Early Carboniferous structural grain in partitioning of structural deformation and vertical basin motions at various scales. Although the older basin history and the basement attract increasing attention, the Pre-Permian tectonics of the SNSB remains little studied with most attention focused on the Permian and younger history. The strong dispersal of existing constraints requires a comprehensive study from Denmark to the UK, i.e. the East Avalonian microplate, bordered by the Variscan Rheïc suture, the Atlantic and Baltica. Based on an extensive literature study and the reinterpretation of publicly available data, linking constraints from the crust and mantle to stratigraphic-sedimentological information, we complement the map of Early Carboniferous rifting of East Avalonia and propose a new tectonic scenario. From the reinterpretation of the boundary between Avalonia and Baltica we propose a new outline for the Avalonian microplate with implications for the tectonics of the North German Basin. Furthermore, we highlight the nature and extent of the major crustal/lithospheric domains with contrasting structural behaviour and the major boundaries that separate them. Results shed light on the effects of long lived differences in crustal fabric that are responsible for spatial heterogeneity in stress and strain magnitudes and zonations of fracturing, burial history and temperature history. The geomechanical control of large crustal-scale fault structures will provide the constraints

  17. Stress Map 2.0: Updating the Stress Map of the Western Canadian Sedimentary Basin

    Science.gov (United States)

    Mallyon, D.; Schmitt, D. R.; Currie, C. A.; Gu, Y. J.; Heidbach, O.

    2015-12-01

    The greatest horizontal compression in much of the Western Canada Sedimentary Basin appears to uniformly trend NE-SW. Beyond this, major gaps remain in our knowledge of stress magnitudes and even faulting regimes. This lack of quantitative information impedes a proper understanding of seismic events that appear to be linked to hydraulic fracturing stimulations. Apart from this immediate concern, such seismicity could impact long term green-house gas sequestration and geothermal energy development. As part of the Helmholtz-Alberta geothermal collaboration, we are developing a program to update this crustal stress state information. The program consists of more immediate studies related to conventional analysis of borehole image logs, core fractures, and transient pressure records as can be made available. Data sets analyzed to date include logs to 3.5 km depth from areas experiencing induced seismicity, from 2.5 km depth within the Precambrian craton in NE Alberta, and to 400 m depth within a large carbonate platform. All these data largely confirm the NE-SW stress directions. In some cases, the configurations of drilling induced tensile fractures and borehole breakouts allow the faulting regime to be constrained. The addition of new seismometers to the region is also allowing for the refinement of earthquake focal mechanisms. Finally, a dramatic contrast in lithosphere thickness, composition and geothermal gradient exists at the contact between the Cordillera and the North American craton; therefore, lithosphere-scale numerical models are also being developed to quantify the relative contribution of geodynamic processes, such as mantle flow and contact geometry, to the observed stress regime within the basin.

  18. The vegetation of the north-western Orange Free State, South Africa. 1. Physical environment

    Directory of Open Access Journals (Sweden)

    M. S. Kooij

    1990-12-01

    Full Text Available The physiography, geology, soil, land types and climate of the north-western Orange Free State are described. The description provides a contextual framework for the subsequent vegetation classification.

  19. Early 21st century climatology of snow cover for the western river basins of the Indus River System

    Science.gov (United States)

    Hasson, S.; Lucarini, V.; Khan, M. R.; Petitta, M.; Bolch, T.; Gioli, G.

    2013-11-01

    In this paper we assess the snow cover and its dynamics for the western river basins of the Indus River System (IRS) and their sub-basins located in Afghanistan, China, India and Pakistan for the period 2001-2012. Moderate Resolution Imaging Spectro-radiometer (MODIS) daily snow products from Terra (MOD) and Aqua (MYD) have been first improved and then analysed on seasonal and annual basis against different topographic parameters (aspect, elevation and slope). Our applied cloud filtering technique has reduced the cloud cover from 37% (MOD) and 43% (MYD) to 7%, thus improving snow cover estimates from 7% (MOD) and 5% (MYD) to 14% for the area of interest (AOI) during the validation period (2004). Our results show a decreasing tendency for the annual average snow cover for the westerlies-influenced basins (Upper Indus Basin, Astore, Hunza, Shigar, Shyok) and an increasing tendency for the monsoon-influenced basins (Jhelum, Kabul, Swat and Gilgit). Regarding the seasonal snow cover, decrease during winter and autumn and increase during spring and summer has been found, which is consistent with the observed cooling and warming trends during the respective seasons. Sub-basins at relatively higher latitude/altitude show higher variability than basins at lower latitude/mid-altitude. Northeastern and northwestern aspects feature larger snow cover. The mean regional snow line altitude (SLA) zones range between 3000 and 5000 m a.s.l. for all basins. Our analysis provides an indication of a decrease in the regional SLA zone, thus indicating a change in the water resources of the studied basins, particularly for the Upper Indus Basin (UIB). Such results are consistent with the observed hydro-climate data, recently collected local perceptions and glacier mass balances for the investigated period. Moreover, our analysis suggests some potential for the seasonal stream flow forecast as a significant negative correlation has been detected for the inter-annual variability of winter

  20. Geothermal systems of the Mono Basin-Long Valley region, eastern California and western Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, C.T.; Flynn, T.; Chapman, R.H.; Trexler, D.T.; Chase, G.R.; Bacon, C.F.; Ghusn, G. Jr.

    1985-01-01

    The region that includes Mono Basin, Long Valley, the Bridgeport-Bodie Hills area, and Aurora, in eastern California and western Nevada was studied to determine the possible causes and interactions of the geothermal anomalies in the Mono Basin-Long Valley region as a whole. A special goal of the study was to locate possible shallow bodies of magma and to determine their influence on the hydrothermal systems in the region. (ACR)

  1. Messinian Events: View from the Provence Basin (Gulf of Lion,Western Mediterranean)

    OpenAIRE

    Bache, François; Gorini, C.; Olivet, Jean-Louis; Rabineau, Marina; Aslanian, Daniel; Suc, J.p.

    2009-01-01

    Though the late Miocene "Messinian Salinity Crisis" has been intensely researched along the circum- Mediterranean basins, few studies have focused on the central part of the Mediterranean Basin and, especially, the pre-salt deposits. Within the Western Mediterranean, the Gulf of Lion is exceptional in that its sedimentary strata have not been significantly deformed. In addition, the Gulf of Lion is characterized by a relatively constant subsidence with continuous accommodation space for sedim...

  2. LLNL Middle East, North Africa and Western Eurasia Knowledge Base

    Energy Technology Data Exchange (ETDEWEB)

    O' Boyle, J; Ruppert, S D; Hauk, T F; Dodge, D A; Ryall, F; Firpo, M A

    2001-07-12

    The Lawrence Livermore National Laboratory (LLNL) Ground-Based Nuclear Event Monitoring (GNEM) program has made significant progress populating a comprehensive Seismic Research Knowledge Base (SRKB) and deriving calibration parameters for the Middle East, North Africa and Western Eurasia (ME/NA/WE) regions. The LLNL SRKB provides not only a coherent framework in which to store and organize very large volumes of collected seismic waveforms, associated event parameter information, and spatial contextual data, but also provides an efficient data processing/research environment for deriving location and discrimination correction surfaces. The SRKB is a flexible and extensible framework consisting of a relational database (RDB), Geographical Information System (GIS), and associated product/data visualization and data management tools. This SRKB framework is designed to accommodate large volumes of data (almost 3 million waveforms from 57,000 events) in diverse formats from many sources (both LLNL derived research and integrated contractor products), in addition to maintaining detailed quality control and metadata. We have developed expanded look-up tables for critical station parameter information (including location and response) and an integrated and reconciled event catalog data set (including specification of preferred origin solutions and associated phase arrivals) for the PDE, CMT, ISC, REB and selected regional catalogs. Using the SRKB framework, we are combining traveltime observations, event characterization studies, and regional tectonic models to assemble a library of ground truth information and phenomenology (e.g. travel-time and amplitude) correction surfaces required for support of the ME/NA/WE regionalization program. We also use the SRKB to integrate data and research products from a variety of sources, such as contractors and universities, to merge and maintain quality control of the data sets. Corrections and parameters distilled from the LLNL SRKB

  3. Head Scarp Boundary for the Landslides in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Polygons represent head scarps and flank scarps associated with landslide deposits in the Little North Santiam River Basin, Oregon. This work was completed as part...

  4. Landslide Deposit Boundaries for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This layer is an inventory of existing landslides deposits in the Little North Santiam River Basin, Oregon (2009). Each landslide deposit shown on this map has been...

  5. Location of Photographs Showing Landslide Features in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent locations of photographs taken of landslides in the Little North Santiam River Basin, Oregon. Photos were taken in spring of 2010 during field...

  6. Timber Harvest Change in the Little North Santiam River Basin, Oregon, 1995 to 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Using available aerial photos from approximately a 15-year period, changes in timber harvest were mapped in the Little North Santiam River Basin, Oregon. Timber...

  7. Orbital forcing in the early Miocene alluvial sediments of the western Ebro Basin, Northeast Spain

    Science.gov (United States)

    Garces, M.; Larrasoaña, J. C.; Muñoz, A.; Margalef, O.; Murelaga, X.

    2009-04-01

    Paleoclimatic reconstructions from terrestrial records are crucial to assess the regional variability of past climates. Despite the apparent direct connection between continental sedimentary environments and climate, interpreting the climatic signature in ancient non-marine sedimentary sequences is often overprinted by source-area related signals. In this regard, foreland basins appear as non-ideal targets as tectonically-driven subsidence and uplift play a major control on the distribution and evolution of sedimentary environments and facies. Foreland basins, however, often yield among the thickest and most continuous stratigraphic records available on continents. The Ebro Basin (north-eastern Spain) is of particular interest among the circum-mediterranean alpine foreland basins because it evolved into a land-locked closed basin since the late Eocene, leading to the accumulation of an exceptionally thick (>5500 m) and continuous sequence of alluvial-lacustrine sediments over a period of about 25 Myr. In this paper we present a detailed cyclostratigraphic study of a 115 m thick section in the Bardenas Reales de Navarra region (western Ebro Basin) in order to test orbital forcing in the Milankovitch frequency band. The study section corresponds to the distal alluvial-playa mud flats which developed in the central sector of the western Ebro Basin, with sediments sourced from both the Pyrenean and Iberian Ranges. Sediments consist of brown-red alluvial clay packages containing minor fine-grained laminated sandstones sheet-beds and channels, grey marls and thin bedded lacustrine limestones arranged in 10 to 20 m thick fining-upwards sequences. Red clayed intervals contain abundant nodular gypsum interpreted as representing a phase of arid and low lake level conditions, while grey marls and limestones indicate wetter intervals recording the expansion of the inner shallow lakes. A magnetostratigraphy-based chronology indicates that the Peñarroya section represents a

  8. The changing cross-border trade dynamics between north-western Uganda, north-eastern Congo and southern Sudan

    OpenAIRE

    Titeca, Kristof

    2009-01-01

    New field work conducted by Kristof Titeca for the CSRC in the border areas of North-Western Uganda, North-Eastern Congo and Southern Sudan yields important lessons about the development of cross-border trading patterns in this region. Informal trade between these countries pre-dates the colonial period, though major political and economic changes have occurred since the 1980's. Drawing from interviews with active traders and government officials, the author argues that internal and external ...

  9. Giant polygons and circular graben in western Utopia basin, Mars: Exploring possible formation mechanisms

    Science.gov (United States)

    Buczkowski, Debra L.; Seelos, Kim D.; Cooke, Michele L.

    2012-08-01

    Large-scale fracture systems surrounding the Utopia basin include giant polygons and circular graben. Data covering the northern Utopia basin now allow high-resolution mapping of these features in all regions of the basin. Giant polygons to the north and south of the basin are different in both size and morphology, leading to the polygon classifications (1) S-style, (2) subdued S-style, (3) northern S-style and (4) N-style. Also, ten circular graben have been identified to the north of the Utopia basin. These have generally larger diameters than southern circular graben, and their fracture morphology is similar to N-style giant polygons. As with southern circular graben, the surface relief of the depression inside the northern circular graben scales directly with diameter. However, northern circular graben have less steep trend slopes, larger average diameters and greater ring spacing compared to southern circular graben of the same diameter and similar distance to the center of the Utopia basin. Both the giant polygons and circular graben of Utopia Planitia are consistent with formation by volumetric compaction of a fine-grained sedimentary material covering an uneven buried surface. Giant polygon size variations can be explained by the material being wet to the south but frozen or partially frozen to the north, while differences between northern and southern circular graben may be attributed to changes in cover thickness. Differences in fracture morphology can be explained by subsequent alteration of the northern troughs due to polar processes.

  10. Structural and stratigraphic analysis of the paleozoic Murzuk and Ghadames basins, western Libya

    Science.gov (United States)

    Karasek, R. M.

    The intracratonic basins in western Libya are characterized by extensional basement controlled faulting along northwest and northeast trends. The northwest southeast trending Tripoli-Soda, Ben Ghenma and Hasi Atshan subsurface arches were uplifted from Cambian through Devonian time. The anomalous west-southwest trending Gargaf Arch acted as a hinge line from Silurian through Devonian time, with consequent paleoslopes to the northwest (Ghadames Basin) and southeast (Murzuk Basin). Paleozoic detrital sediments are up to 1500 m thick in the Murzuk Basin and 2500 m thick in the Ghadames Basin. Five depositional sequences comprise transgressive-regressive cycles of deposition from parallic (coarse grained) to marine (fine-grained). Detailed environmental interpretation of the sequences is based on outcrop models for the Middle Devonian-Lower Carboniferous Aouinet Ouenine and Shatti Formations.

  11. Variability of mineral dust deposition in the western Mediterranean basin and south-east of France

    Science.gov (United States)

    Vincent, Julie; Laurent, Benoit; Losno, Rémi; Bon Nguyen, Elisabeth; Roullet, Pierre; Sauvage, Stéphane; Chevaillier, Servanne; Coddeville, Patrice; Ouboulmane, Noura; di Sarra, Alcide Giorgio; Tovar-Sánchez, Antonio; Sferlazzo, Damiano; Massanet, Ana; Triquet, Sylvain; Morales Baquero, Rafael; Fornier, Michel; Coursier, Cyril; Desboeufs, Karine; Dulac, François; Bergametti, Gilles

    2016-07-01

    Previous studies have provided some insight into the Saharan dust deposition at a few specific locations from observations over long time periods or intensive field campaigns. However, no assessment of the dust deposition temporal variability in connection with its regional spatial distribution has been achieved so far from network observations over more than 1 year. To investigate dust deposition dynamics at the regional scale, five automatic deposition collectors named CARAGA (Collecteur Automatique de Retombées Atmosphériques insolubles à Grande Autonomie in French) have been deployed in the western Mediterranean region during 1 to 3 years depending on the station. The sites include, from south to north, Lampedusa, Majorca, Corsica, Frioul and Le Casset (southern French Alps). Deposition measurements are performed on a common weekly period at the five sites. The mean dust deposition fluxes are higher close to the northern African coasts and decrease following a south-north gradient, with values from 7.4 g m-2 year-1 in Lampedusa (35°31' N, 12°37' E) to 1 g m-2 year-1 in Le Casset (44°59' N, 6°28' E). The maximum deposition flux recorded is of 3.2 g m-2 wk-1 in Majorca with only two other events showing more than 1 g m-2 wk-1 in Lampedusa, and a maximum of 0.5 g m-2 wk-1 in Corsica. The maximum value of 2.1 g m-2 year-1 observed in Corsica in 2013 is much lower than existing records in the area over the 3 previous decades (11-14 g m-2 year-1). From the 537 available samples, 98 major Saharan dust deposition events have been identified in the records between 2011 and 2013. Complementary observations provided by both satellite and air mass trajectories are used to identify the dust provenance areas and the transport pathways from the Sahara to the stations for the studied period. Despite the large size of African dust plumes detected by satellites, more than 80 % of the major dust deposition events are recorded at only one station, suggesting that the dust

  12. Basin Analysis and Petroleum System Characterisation of Western Bredasdorp Basin, Southern Offshore of South Africa: Insights from a 3d Crust-Scale Basin Model - (Phase 1)

    Science.gov (United States)

    Sonibare, W. A.; Scheck-Wenderoth, M.; Sippel, J.; Mikeš, D.

    2012-04-01

    In recent years, construction of 3D geological models and their subsequent upscaling for reservoir simulation has become an important tool within the oil industry for managing hydrocarbon reservoirs and increasing recovery rate. Incorporating petroleum system elements (i.e. source, reservoir and trap) into these models is a relatively new concept that seems very promising to play/prospect risk assessment and reservoir characterisation alike. However, yet to be fully integrated into this multi-disciplinary modelling approach are the qualitative and quantitative impacts of crust-scale basin dynamics on the observed basin-fill architecture and geometries. The focus of this study i.e. Western Bredasdorp Basin constitutes the extreme western section of the larger Bredasdorp sub-basin, which is the westernmost depocentre of the four southern Africa offshore sub-basins (others being Pletmos, Gamtoos and Algoa). These basins, which appear to be initiated by volcanically influenced continental rifting and break-up related to passive margin evolution (during the Mid-Late Jurassic to latest Valanginian), remain previously unstudied for crust-scale basin margin evolution, and particularly in terms of relating deep crustal processes to depo-system reconstruction and petroleum system evolution. Seismic interpretation of 42 2D seismic-reflection profiles forms the basis for maps of 6 stratigraphic horizons which record the syn-rift to post-rift (i.e. early drift and late drift to present-day seafloor) successions. In addition to this established seismic markers, high quality seismic profiles have shown evidence for a pre-rift sequence (i.e. older than Late Jurassic >130 Ma). The first goal of this study is the construction of a 3D gravity-constrained, crust-scale basin model from integration of seismics, well data and cores. This basin model is constructed using GMS (in-house GFZ Geo-Modelling Software) while testing its consistency with the gravity field is performed using IGMAS

  13. Gravity modeling constraints on the Gatun-Chagres Basin and tectonic evolution of north-central Panama

    Science.gov (United States)

    Mynhier, Kelci

    The Oligocene-Miocene collision between Panama and South America significantly influenced ocean currents, global climate, and species diversification. Intraplate deformation of the Panama Block also played an important role in the evolution of this tectonic system, but is not well understood. A high-resolution gravity survey, coupled with geologic observations, was conducted in north-central Panama to better constrain the processes responsible for the Isthmus' modern configuration. Approximately 110 gravity stations were collected from Colon to Nombre de Dios, Panama and merged with existing data. Subsequently, four 2.5-D gravity models were produced to constrain the geometry of the Gatun-Chagres Basin using different sedimentary densities (1.8, 2.0, and 2.2 g/cm 3) to produce a realistic range of basin thicknesses. Overall, models with an average basin density of 2.0 g/cm3 are most consistent with offshore seismic profiles and field evidence, suggesting basin thickness is ~3.0--3.5 km. Previous seismic reflection data and geochemical analyses of Miocene arc volcanic rocks delineate a zone of extension in the Panama Canal Region, and gravity analysis from this study supports this hypothesis. Field evidence of multiple NW-facing normal faults suggests that they separate the basin from uplifted arc basement rocks east of the Canal, resulting in a 60 mGal gravity gradient. Beneath the basin, gravity models indicate ~5--10 km of crustal thinning. 3-D reconstruction of the 2.5-D models show a northward thickening basin and two depocenters that correspond to the Rio Indio and Toro facies of the Chagres Formation. This analysis suggests two directional extension of the Gatun-Chagres Basin; an east-west direction corresponding to the initial formation of the basin, and a modern northwest-southeast direction. To the northeast, gravity modeling indicates that there is a ~150 m-thick, Cretaceous-Holocene sedimentary basin present from Portobelo to Nombre de Dios. Sedimentary

  14. Late Cretaceous stratigraphy of the Upper Magdalena Basin in the Payandé-Chaparral segment (western Girardot Sub-Basin), Colombia

    Science.gov (United States)

    Barrio, C. A.; Coffield, D. Q.

    1992-02-01

    The Cretaceous section on the western margin of the Girardot Sub-Basin, Upper Magdalena Valley, is composed of the Lower Sandstone (Hauterivian-Barremian?), Tetuán Limestone (pre-Aptian?), and Bambuca Shale (pre-Aptian?), and the following formations: Caballos (Aptian-Albian), Villeta (Albian-Campanian), Monserrate (Campanian-Maastrichtian), and Guaduas (Maastrichtian-Paleocene). The Lower Sandstone is composed of quartz arenites with abundant calcareous cement; the Tetuúan Limestone is a succession of fossiliferous limestones and calcareous shales; the the Bambuca Shale is composed of black shales that grade upward to micritic limestones and calcarenites. The Caballos Formation comprises three members: a lower member of quartz arenites, a middle member of black shales and limestones, and an upper member of crossbedded, coarsening-upward quartz arenites. The Villeta Formation is a sequence of shales intercalated with micritic limestones and calcarenites. Two levels of chert (Upper and Lower Chert) are differentiated within the Villeta Formation throughout the study area, with a sandstone unit (El Cobre Sandstone) to the north. The Monserrate Formation is composed of quartz arenites, with abundant crossbedding, and locally of limestone breccias and coarse-grained fossiliferous packstones. The Guaduas Formation is a monotonous succession of red shales and lithic sandstones. Our data suggest three major transgressive-regressive cycles in the Girardot Sub-Basin. The first cycle (Hauterivian?-lower Aptian) is represented by the Lower Sandstone-Tetuán-Bambuca-lower Caballos succession, the second cycle (Aptian-Albian) by the middle-upper Caballos members, and the third cycle (Albian-Paleocene) by the lower Villeta-Monserrate-Guaduas succession. Previous studies proposed a eustatic control during deposition of the Upper Cretaceous in the Upper Magdalena Valley. The lowermost transgressive-regressive cycle was not previously differentiated in the study area, and this

  15. Stress distribution and seismicity patterns of the 2011 seismic swarm in the Messinia basin, (South-Western Peloponnesus, Greece

    Directory of Open Access Journals (Sweden)

    G. Chouliaras

    2013-01-01

    Full Text Available In this investigation we examine the local stress field and the seismicity patterns associated with the 2011–2012 seismicity swarm in the Messinia basin, south-western Peloponnesus, Greece, using the seismological data of the National Observatory of Athens (NOA. During this swarm more than 2000 events were recorded in a 12 month period by the Hellenic Unified Seismological Network (HUSN and also by the additional local installation of four portable broadband seismographic stations by NOA.

    The results indicate a Gaussian distribution of swarm activity and the development of a seismicity cluster in a pre-existing seismic gap within the Messinia basin. Centroid Moment Tensor solutions demonstrate a normal fault trending northwest–southeast and dipping to the southwest primarily due to an extensional stress field. During this seismicity swarm an epicentre migration of the three largest shocks is observed, from one end of the rupture zone in the north-western part of the cluster, towards the other edge of the rupture in the south-eastern part of the cluster. This migration is found to follow the Coulomb failure criterion that predicts the advancement and retardation of the stress field and the patterns of increases and decreases of the seismicity rate (b-value of the frequency–magnitude relation.

  16. Nature of the crust in the Laxmi Basin (14°-20°N), western continental margin of India

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, K.S.; Rao, D.G.; Sar, D.

    and modelled gravity and magnetic anomalies for determining nature of the crust. Basement of the Laxmi Basin includes numerous highs, which make the basement uneven and shallower compared to the Western Basin. The Laxmi Basin is characterised by a broad gravity...

  17. Climate variation and prediction of rapid intensification in tropical cyclones in the western North Pacific

    Science.gov (United States)

    Wang, B.; Zhou, X.

    2008-02-01

    all category 4 and 5 hurricanes in the Atlantic basin and 90% of the super typhoons in the western North Pacific experience at least one RI process in their life cycles. Over the past 40 years, the annual total of RI in the western North Pacific shows pronounced interdecadal variation but no significant trend. This result suggests that the number of supper typhoons has no upward trend in the past 40 years. Our results also suggest that when the mean latitude, where the tropical storms form, shifts southward (either seasonally or from year to year) the proportion of super typhoon or major hurricane will likely increase. This shift is determined by large scale circulation change rather than local SST effects. This idea differs from the current notion that increasing SST can lead to more frequent occurrence of category 4 or 5 hurricanes through local thermodynamics.

  18. The recent extreme hydrological events in the Western Amazon Basin: The role of the Pacific and Atlantic Oceans

    Science.gov (United States)

    Espinoza, J.; Ronchail, J.; Guyot, J.; Santini, W.; Lavado, W.; Ore-Hybam Observatory

    2013-05-01

    The Peruvian Amazonas River, the main western tributary of the Amazon basin, has a huge drainage (750 000 km2, 50% of which lies in the Andes) and a mean discharge estimated in 32 000 m3/s, which correspond to 15% of the Amazon discharge at the estuary. Recently, in a context of significant discharge diminution during the low-water season (1970-2012), severe hydrological events, as intense droughts and floods, have been reported in the Peruvian Amazonas River. As they have not been always observed in other regions of the Amazon basin and because they have strong impacts on vulnerable riverside residents, we shall focus on the origin and the predictability of the western Amazon extremes, providing a review of the main findings about the climate features during recent extreme hydrological events in western Amazon. While the lowest discharge value was observed in September 2010 (8 300 m3/s) at the hydrological Tamshiyacu station (near to Iquitos city), a rapid transition toward a high discharge was noticed in April 2011 (45 000 m3/s). Finally, in April 2012, during the on going high waters period, the Amazonas River is experimenting its historical highest discharge (55 000 m3/s). Our work is based on several datasets including in-situ discharge and rainfall information from ORE-HYBAM observatory. Extreme droughts (1995, 2005 and 2010) are generally associated with positive SST anomalies in the tropical North Atlantic and weak trade winds and water vapor transport toward the western Amazon, which, in association with increased subsidence over central and southern Amazon, explain the lack of rainfall and very low discharge values. But, in 1998, toward the end of the 1997-98 El Niño event, the drought has been more likely related to an anomalous divergence of water vapor in the western Amazon that is characteristic of a warm event in the Pacific. The years with a rapid transition form low waters to very high floods (e.g. September 2010 to April 2011) are characterized

  19. Geology and natural gas occurrence, western Williston Basin

    Energy Technology Data Exchange (ETDEWEB)

    McCrae, R.O.; Swenson, R.E.

    1968-01-01

    The W. Williston Basin has produced gas since a 1913 discovery at Cedar Creek anticline, but during the past decade nearly all the gas found has been in solution in oil. In a sedimentary rock section averaging 10,000 ft in thickness, about one-third of the material, in approx. the lower half of the section, consists of carbonate and evaporites. The rest of the beds are principally sandstone and shale of shallow-marine deposition. All commercial gas in Paleozoic rocks is in solution in oil. Small gas reserves have been found in fractured siltstones of the Cretaceous Colorado shale at Hardin, and in the Shannon sandstone at Pumpkin Creek. Most of the gas in the W. Williston Basin is in nonassociated accumulations in and adjacent to the Cretaceous Judith River and Eagle formations. The trapping is related partly to folding, but also is at the extreme seaward limits of sandstone tongues. Porosity of less than 10% and low permeability values are characteristic of the reservoirs and fracturing is regarded as important in improving overall permeability of the reservoirs. At Cedar Creek anticline, 6 million cu ft a day of 90% nitrogen gas was treated in a Cambrian sandstone.

  20. Origin of back-arc basins and effects of western Pacific subduction systems on eastern China geology

    Science.gov (United States)

    Niu, Y.

    2013-12-01

    Assuming that subduction initiation is a consequence of lateral compositional buoyancy contrast within the lithosphere [1], and recognizing that subduction initiation within normal oceanic lithosphere is unlikely [1], we can assert that passive continental margins that are locations of the largest compositional buoyancy contrast within the lithosphere are the loci of future subduction zones [1]. We hypothesize that western Pacific back-arc basins were developed as and evolved from rifting at passive continental margins in response to initiation and continuation of subduction zones. This hypothesis can be tested by demonstrating that intra-oceanic island arcs must have basement of continental origin. The geology of the Islands of Japan supports this. The highly depleted forearc peridotites (sub-continental lithosphere material) from Tonga and Mariana offer independent lines of evidence for the hypothesis [1]. The origin and evolution of the Okinawa Trough (back-arc basin) and Ryukyu Arc/Trench systems represents the modern example of subduction initiation and back-arc basin formation along a (Chinese) continental margin. The observation why back-arc basins exit behind some subduction zones (e.g., western Pacific) but not others (e.g., in South America) depends on how the overlying plate responds to subduction, slab-rollback and trench retreat. In the western Pacific, trench retreat towards east results in the development of extension in the upper Eurasian plate and formation of back-arc basins. In the case of South America, where no back-arc basins form because trench retreat related extension is focused at the 'weakest' South Mid-Atlantic Ridge. It is thus conceptually correct that the South Atlantic is equivalent to a huge 'back-arc basin' although its origin may be different. Given the negative Clayperon slope of the Perovskite-ringwoodite phase transition at the 660 km mantle seismic discontinuity (660-D), slab penetration across the 660-D is difficult and

  1. Western spotted frog (Rana pretiosa) distribution in the Bonneville Basin of western Utah: Research in progress

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report provides information on the western spotted frog Rana pretiosa which occurs in Tule Valley, Utah. The following topics are discussed; general...

  2. Geologic Assessment of Undiscovered Oil and Gas Resources of the North Cuba Basin, Cuba

    Science.gov (United States)

    Schenk, Christopher J.

    2010-01-01

    Petroleum generation in the North Cuba Basin is primarily the result of thrust loading of Jurassic and Cretaceous source rocks during formation of the North Cuba fold and thrust belt in the Late Cretaceous to Paleogene. The fold and thrust belt formed as Cuban arc-forearc rocks along the leading edge of the Caribbean plate translated northward during the opening of the Yucatan Basin and collided with the passive margin of southern North America in the Paleogene. Petroleum fluids generated during thrust loading migrated vertically into complex structures in the fold and thrust belt, into structures in the foreland basin, and possibly into carbonate reservoirs along the margins of the Yucatan and Bahama carbonate platforms. The U.S. Geological Survey (USGS) defined a Jurassic-Cretaceous Composite Total Petroleum System (TPS) and three assessment units (AU)-North Cuba Fold and Thrust Belt AU, North Cuba Foreland Basin AU, and the North Cuba Platform Margin Carbonate AU-within this TPS based mainly on structure and reservoir type (fig. 1). There is considerable geologic uncertainty as to the extent of petroleum migration that might have occurred within this TPS to form potential petroleum accumulations. Taking this geologic uncertainty into account, especially in the offshore area, the mean volumes of undiscovered resources in the composite TPS of the North Cuba Basin are estimated at (1) 4.6 billion barrels of oil (BBO), with means ranging from an F95 probability of 1 BBO to an F5 probability of 9 BBO; and (2) 8.6 trillion cubic feet of of gas (TCFG), of which 8.6 TCFG is associated with oil fields, and about 1.2 TCFG is in nonassociated gas fields in the North Cuba Foreland Basin AU.

  3. Different sedimentological and thermal evolution of three north-pyrenean basins during their set-up

    Science.gov (United States)

    Chelalou, Roman; Nalpas, Thierry; Bousquet, Romain; Lahfid, Abdeltif

    2015-04-01

    The Pyrenean belt is resulting in the inversion of several lower Cretaceous basins, separating the Iberia micro-plate from the Eurasia plate. The eat-west oriented basins are well known for their high-temperature metamorphism synchronous of the last deposits during Aptian-Albian times. For the first time, we present a combined sedimentological and thermal study of three north pyrenean basins (Boucheville, St Paul-de-Fenouillet and Bas-Agly). With the help of detailed stratigraphic logs of each basin, we propose restored cross-sections for the whole area. North-south sections across Boucheville and St Paul-de-Fenouillet basins show that theses basins have large asymmetrical structure. The Boucheville basin is a large anticline bordered by two isoclinal syncline highly skewed, while the St Paul-de-Fenouillet one is a unique syncline. Detailed sedimentalogical observations show common features for these basins: deposits of white limestones and breccias during the Jurassic time following by black sandstones with a calcareous matrix of lower Cretaceous age. On one hand, Jurassic limestones were deposited on a shelf environment and their thickness is homogeneous all over each basin. On the other hand, sandstones deposits seem to occur at greater depths during the Albian time and are displaying asymmetrical north-south variation of their thickness. The quantification of the temperature overprint occurred in the basin was done using the graphitisation of the carbonaceous material, and was measured by RAMAN spectroscopy (Lahfid et al. 2010). Despite their similar deposits, the mapping of the temperature-peak inside the three basins show contrasted thermal evolution. Then we document a lower temperature overprint around 150-200˚C in the northern basin {St Paul-de-Fenouillet) while the highest overprint up to 600˚C has been reached in the southern basin (Boucheville) in which diopside - scapolite and also probably olivine are occurring. These three north-pyrenean basin turn

  4. New Discovery of Coral Rubbings in the North-Western Gulf of Kachchh, Gujarat, Western India-GIS Based Evaluation

    Institute of Scientific and Technical Information of China (English)

    J. Sesh Serebiah; M. Rajkumar; SUN Jun; B. A. Venmathi Maran; A. Saravanakumar; G. A. Thivakaran

    2011-01-01

    The Gulf of Kachchh in western India, with its arid climate, large semi-diurnal tidal amplitudes, negative water balance and near-pristine water quality, is being extensively developed as oil importing bases for economic reasons in connection with its proximity to the oil exporting countries of the Middle East. Besides, new coral robbings were sighted in Jakhau, north-western Gulf of Kachchh. Dredging in Mandvi of the north Gulf covering 3.5 km2 revealed a similar assortment of live corals with their associated flora and fauna. These pioneering observations demonstrate that there exist live corals of young polyps-colony of Favia sp. belonging to the family Faviidae in the north-western Gulf of Kachchh. The environmental parameters there were carefully recorded as: surface water temperature (℃) varying from 29 to 31.8, salinity (ppt), pH, dissolved oxygen (mgL-l)and total suspended solids (mgL-1) in the ranges of 37- 43.5, 7.7- 8.45, 5.4 - 6.8 and 11- 31, respectively.

  5. The Origin of Basin of Great Lakes in Western Mongolia: Glaciated Super Valley, Not Super Flooding

    Science.gov (United States)

    Khukhuudei, Ulambadrakh; Otgonbayar, Orolzodmaa

    2015-04-01

    Research for morphology, its origin of the Basin of Great Lakes in Western Mongolia, is few and far between, particularly, any in recent years. The origin of the morphology of the basin presents a new study, combining previous study materials, their results and interpreting the digital photos. Also the main bases of theory is Pleistocene Last Glacial Maximum distribution. Many scholars have proven that global glaciation covered many areas of the Northern Hemisphere during the Pleistocene era. This global glaciation occurred in the northwest part of Mongolia to Mongolian Altay, Khangay and Khuvsgul mountain range. At the same time, the present appearance of basin that developed inheriting since the Mesozoic era, forms by global glaciation. The morphology of Basin of Great Lakes is super trough or glaciated super valley. At current day, "knock and lochan" topography (scoured region) and rock drumlins lie in the central part of the basin. Huge meltwater from this glaciation formed Shargasub-basin as a super kettle hole by erosion and overflowed water from it formed pluvial basins or big lakes in the Lake Valley.

  6. Biodegradation and origin of oil sands in the Western Canada Sedimentary Basin

    Institute of Scientific and Technical Information of China (English)

    Zhou Shuqing; Huang Haiping; Liu Yuming

    2008-01-01

    The oil sands deposits in the Western Canada Sedimentary Basin (WCSB) comprise of at least 85% of the total immobile bitumen in place in the world and are so concentrated as to be virtually the only such deposits that are economically recoverable for conversion to oil.The major deposits are in three geographic and geologic regions of Alberta: Athabasca,Cold Lake and Peace River.The bitumen reserves have oil gravities ranging from 8 to 12° API,and are hosted in the reservoirs of varying age,ranging from Devonian (Grosmont Formation) to Early Cretaceous (Mannville Group).They were derived from light oils in the southern Alberta and migrated to the north and east for over 100 km during the Laramide Orogeny,which was responsible for the uplift of the Rocky Mountains.Biodegradation is the only process that transforms light oil into bitumen in such a dramatic way that overshadowed other alterations with minor contributions.The levels of biodegradation in the basin increasing from west (non-biodegraded) to east (extremely biodegraded) can be attributed to decreasing reservoir temperature,which played the primary role in controlling the biodegradation regime.Once the reservoir was heated to approximately 80 ℃,it was pasteurized and no biodegradation would further occur.However,reservoir temperature could not alone predict the variations of the oil composition and physical properties.Compositional gradients and a wide range of biodegradation degree at single reservoir column indicate that the water-leg size or the volume ratio of oil to water is one of the critical local controls for the vertical variations of biodegradation degree and oil physical properties.Late charging and mixing of the fresh and degraded oils ultimately dictate the final distribution of compositions and physical properties found in the heavy oil and oil sand fields.Oil geochemistry can reveal precisely the processes and levels that control these variations in a given field,which opens the

  7. The Post-Permian evolution of the Northern Part of the North German Basin

    Science.gov (United States)

    Hansen, M. B.; Huebscher, C.; Lykke-Andersen, H.; Gajewski, D.; Dehghani, A.; Reicherter, K.

    2004-12-01

    In the frame of the Priority Program 1135 of the German Research Foundation (DFG) "Dynamics of sedimentary systems under varying stress conditions by example of the Central European Basin System", the scientific goal of the NeoBaltic project is to describe the post-Permian to recent geological evolution of the entire western Baltic Sea region, with a special emphasis on neotectonic activity and it relation to salt dynamics. The western Baltic Sea comprises the northern part of the North German Basin (NGB), a part of the Central European Basin System (CEBS), and the transitional zone between the NGB and the Baltic Shield. In order to investigate these scientific goals the Universities of Aarhus (Denmark) and Hamburg (Germany) has since 1998 completed seven marine campaigns in the western Baltic Sea, collecting 2D high resolution seismic (HRS), gravity and magnetic data in the entire region during different projects. Since 2003 all these data has been available for the NeoBaltic project. All together the data pool have more than 7000 km HRS, 5000 km gravity and 4000 km magnetic data. Until now the project work has been focused on the completion of the data processing and the digital interpretation of important Mesozoic and Cenozoic markers on the seismic sections from the Bays of Kiel and Mecklenburg. Furthermore, several maps have been completed from the potential field data (gravity and magnetic). As a result of the digital interpretation of the HRS data, the overall geological evolution of the northern part of the NGB can be subdivided into four distinct periods. During the Triassic and the Early Jurassic, E-W extension and the deposition of clastic sediments initiated the movement of the underlying Zechstein evaporites. This is seen by the presence of several salt pillows in the region. The deposition ceased during the Middle Jurassic, when the entire area was uplifted, due to the Mid North Sea Doming. The uplift resulted in a pronounced erosion of Upper Triassic

  8. Brittle Deformation in the Ordos Basin in response to the Mesozoic destruction of the North China Craton

    Science.gov (United States)

    Wang, Q.; Jiang, L.

    2012-12-01

    Craton is continental block that has been tectonically stable since at least Proterozoic. Some cratons, however, become unstable for some geodynamic reasons. The North China Craton (NCC) is an example. Structure geological, geochemical, and geophysical works have revealed that the NCC was destructed in Cretaceous and that lithosphere thickness beneath the eastern NCC were thinned by 120 km. The present study will focus on deformation of the western NCC, and to understand the effect of the Mesozoic destruction of the North China Craton (NCC). Structural partitioning of the Ordos Basin, which is located in the western NCC, from the eastern NCC occurred during the Mesozoic. Unlike the eastern NCC where many Cretaceous metamorphic core complexes developed, sedimentary cover of the NCC remains nearly horizontal and deformation is manifested by joint. We visited 216 sites of outcrops and got 1928 joints measurements, among which 270 from Jurassic sandstones, 1378 from the Upper Triassic sandstones, 124 from the Middle and Lower Triassic sandstones, and 156 from Paleozoic sandstones. In the interior of the Ordos Basin, joints developed quite well in the Triassic strata, while joints in the Jurassic stata developed weakly and no joint in the Cretaceous strata. The Mesozoic stratigraphic thickness are: 1000 meters for the Lower Triassic, the Middle Triassic sandstone with thickness of 800 meters, 3000 meters for the Upper Triassic, 4000 meters for the Jurassic, and 1100 meters for the Lower Cretaceous. The vertical difference in joint development might be related to the burying depth of the strata: the higher the strata, the smaller the lithostatic stress, and then the weaker the joint. Joints in all stratigraphic levels showed a similar strain direction with the sigma 1 (the maximum pressure stress) vertical and the sigma 3 (the minimum pressure stress) horizontal and running N-S. The unconformity below the Cretaceous further indicates that joints in Jurassic and Triassic

  9. Implications of Spatial Variability in Heat Flow for Geothermal Resource Evaluation in Large Foreland Basins: The Case of the Western Canada Sedimentary Basin

    Directory of Open Access Journals (Sweden)

    Simon Weides

    2014-04-01

    Full Text Available Heat flow and geothermal gradient of the sedimentary succession of the Western Canada Sedimentary Basin (WCSB are mapped based on a large thermal database. Heat flow in the deep part of the basin varies from 30 mW/m2 in the south to high 100 mW/m2 in the north. As permeable strata are required for a successful geothermal application, the most important aquifers are discussed and evaluated. Regional temperature distribution within different aquifers is mapped for the first time, enabling a delineation of the most promising areas based on thermal field and aquifer properties. Results of previous regional studies on the geothermal potential of the WCSB are newly evaluated and discussed. In parts of the WCSB temperatures as high as 100–210 °C exist at depths of 3–5 km. Fluids from deep aquifers in these “hot” regions of the WCSB could be used in geothermal power plants to produce electricity. The geothermal resources of the shallower parts of the WCSB (>2 km could be used for warm water provision (>50 °C or district heating (>70 °C in urban areas.

  10. Living on the edge: The oxygen isotope record of Eocene Basins at the margin of the Cenozoic North American plateau

    Science.gov (United States)

    Methner, Katharina; Mulch, Andreas; Chamberlain, Page

    2013-04-01

    Topography has a strong impact on atmospheric circulation and precipitation patterns and is a key element in reconstructing the dynamics of mountain building processes. The topographic evolution of the world's major orogens remains one of the most important questions when discussing the interactions among tectonics, climate, and Earth surface processes. Here, we focus on the spatial and temporal development of topography and relief in the western North American Cordillera and how changes in the topography may have affected precipitation patterns and vice versa. In this context, we sampled more than 20 sections in Eocene to Oligocene terrestrial (intermontane?) basins (Chumstick, Swauk, and Chuckanut) in western and central Washington (USA) to the W and E of the modern Cascades. Oxygen isotope analysis of pedogenic carbonate in these sections allows us to reconstruct the isotopic composition of ancient soilwater or groundwater, and ultimately precipitation. Oxygen isotope measurements of pedogenic concretions and calcic horizons interestingly yield uniformly low δ18O values of 10 to 13‰ SMOW despite the proximity of all sections to the Pacific moisture source. These extremely low oxygen isotope values can result from (1) highly 18O-depleted meteoric waters (soil- or groundwater), (2) burial diagenesis at moderate temperatures and interaction with 18O-depleted (ground)water, and (3) high burial temperatures and and exchange with basins brines. Vitrinite reflectance data and preservation of primary soil structures such as rootlets, root casts, burrows, or even preserved wood fragments clearly show that some of the low-d18O sections were not affected by high degrees of burial diagenesis. Thus, we believe that the primary isotopic signal of ancient soil- or groundwater is preserved at least in parts (if not in all) of these basins. Low δ18O values of pedogenic carbonate require highly 18O-depleted meteoric water, which in turn, would require high elevation either at

  11. Afghanistan Reveals the Source of Atmospheric Nitrogen during North Western Monsoons

    OpenAIRE

    Ayse Ozlem Goral; Amir Hadji Ali Ghandi; Ahmet Cemal Saydam

    2014-01-01

    Chemical analysis of soil samples collected from Afghanistan have shown that those regions having capability of generating wind-induced dust at northern and south western territories have the capability of supplying nitrates and nitrites in addition to crustal materials. Together with all the other essential elements Afghan soil samples has the potential of controlling so far unexplained phytoplankton bloom and excess nitrate and nitrites during the course of NWM (North Western Monsoons) over...

  12. Afghanistan Reveals the Source of Atmospheric Nitrogen during North Western Monsoons

    Directory of Open Access Journals (Sweden)

    Ayse Ozlem Goral

    2014-10-01

    Full Text Available Chemical analysis of soil samples collected from Afghanistan have shown that those regions having capability of generating wind-induced dust at northern and south western territories have the capability of supplying nitrates and nitrites in addition to crustal materials. Together with all the other essential elements Afghan soil samples has the potential of controlling so far unexplained phytoplankton bloom and excess nitrate and nitrites during the course of NWM (North Western Monsoons over the surface waters of Arabian Sea

  13. THE TECTONOPHYSICAL RESEARCHES OF THE SEMISAMSKAYA ANTICLINE (NORTH-WESTERN CAUCASUS FOLD AND THRUST BELT

    Directory of Open Access Journals (Sweden)

    A. V. Marinin

    2015-09-01

    Full Text Available Structural paragenetic and cataclastic analysis methods were applied to study tectonic fracturing within one of the folds of the southern wing of the North-Western Caucasus fold-and-thrust belt. The object of the study was the Semisamskaya anticline (Fig. 1 and 2 comprising the Upper Cretaceous and Paleogenic layered terrigenic-carbonate sediments that contain various well-developed geological indicators of palaeostresses (Fig. 3, 5, 7, and 9.In the folded structure under study, a paragenesis is revealed which is associated with the effect of sub-horizontal minimum compression (deviator extension stresses of the north-western orientation (NW 320° and traced by detached normal fault systems striking in the north-eastern direction (Fig. 6, 8, 10, 11, and 17. Upthrust-overthrust systems of the north-western strike (NW–SE, which are of importance for the whole folded structure of the North-Western Caucasus, are mainly manifested in the wings of the Semisamskaya anticline (Fig. 6, 12, and 13.The overall field of stresses related to formation of the folded structure is significantly variable as evidenced by the pattern of local parameters of the paleostress field, which are calculated by the cataclastic analysis method (Figure 15, 16, and 17.It is established that the geodynamic regime within the anticline is considerably variable by types (Fig. 18. Areas with horizontal extension in the axial part of the fold are replaced by areas of horizontal compression at its wings (Fig. 19.  

  14. Invasion of the red seaweed Heterosiphonia japonica spans biogeographic provinces in the Western North Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Christine Newton

    Full Text Available The recent invasion of the red alga Heterosiphonia japonica in the western North Atlantic Ocean has provided a unique opportunity to study invasion dynamics across a biogeographical barrier. Native to the western North Pacific Ocean, initial collections in 2007 and 2009 restricted the western North Atlantic range of this invader to Rhode Island, USA. However, through subtidal community surveys, we document the presence of Heterosiphonia in coastal waters from Maine to New York, USA, a distance of more than 700 km. This geographical distribution spans a well-known biogeographical barrier at Cape Cod, Massachusetts. Despite significant differences in subtidal community structure north and south of Cape Cod, Heterosiphonia was found at all but two sites surveyed in both biogeographic provinces, suggesting that this invader is capable of rapid expansion over broad geographic ranges. Across all sites surveyed, Heterosiphonia comprised 14% of the subtidal benthic community. However, average abundances of nearly 80% were found at some locations. As a drifting macrophyte, Heterosiphonia was found as intertidal wrack in abundances of up to 65% of the biomass washed up along beaches surveyed. Our surveys suggest that the high abundance of Heterosiphonia has already led to marked changes in subtidal community structure; we found significantly lower species richness in recipient communities with higher Heterosiphona abundances. Based on temperature and salinity tolerances of the European populations, we believe Heterosiphonia has the potential to invade and alter subtidal communities from Florida to Newfoundland in the western North Atlantic.

  15. 12 Blocks Open in North west China's Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    PetroChina Foreign Cooperation Administration Depa

    2006-01-01

    @@ After having opened up for 20 years, the field of oil/gas exploration and development in China is witnessing a new round of high tide to attract foreign investment.PetroChina, China's biggest oil/gas producer and supplier,decided to offer 12 blocks totaling an acreage of 110,000sq.km. in Tarim Basin to players of the industry globally.The project is the biggest oil/gas deal in China aiming at foreign cooperation for approximately 12 years, in which the 12 blocks that will be offered located mainly in southwestern, central and eastern Tarim Basin. It will enable PetroChina to combine its experience and cognition on the geological condition of Tarim Basin with the updated prospecting concept and advanced prospecting technique in the world, improve the proved degree of oil and gas resources in Tarim Basin and achieve a big breakthrough in oil and gas exploration.

  16. Proceedings of the North Aleutian Basin information status and research planning meeting.

    Energy Technology Data Exchange (ETDEWEB)

    LaGory, K. E.; Krummel, J. R.; Hayse, J. W.; Hlohowskyj, I.; Stull, E. A.; Gorenflo, L.; Environmental Science Division

    2007-10-26

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant ecological and natural resources. The Basin includes most of the southeastern part of the Bering Sea continental shelf including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals including federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012 and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory (Argonne) were contracted to assist the MMS Alaska Outer Continental Shelf (OCS) Region in identifying and prioritizing information needs related to the North Aleutian Basin and potential future oil and gas leasing and development activities. The overall approach focused on three related but separate tasks: (1) identification and

  17. Hydrogeological features conditioning trophic levels of quarry lakes in western Po plain (north-western Italy)

    Science.gov (United States)

    De Luca, Domenico Antonio; Castagna, Sara; Lasagna, Manuela

    2013-04-01

    Quarry lakes occur in plains areas due to the extraction of alluvial sand and gravel used for grout and concrete in the construction industry. Excavation depths can reach and intersect the groundwater surface, thus creating a lake. Because of the need to optimize efficiency, the number of active open pit mines has increased in recent years; consequently, the global number of pit lakes will increase in coming decades (Castendyk and Eary 2009; Klapper and Geller 2001; Castro and Moore 2000). Similar to natural lakes, pit lakes are subject to eutrophication process, both during and after quarrying activity; during mining activity, the eutrophic level is strongly controlled by the excavation method. In the Piedmont territory (north-western Italy) there are 70 active quarry lakes, corresponding to approximately 0.1% of the entire plain area. Quarry lakes, located primarily along the main rivers occur in alluvial deposits of the plain area and have average depths between 20 and 30 m (maximum of 60 m deep) and surface areas between 3 and 30 hectares (Castagna 2008). The present study describes the trophic status of 23 active quarry lakes in the Piedmont plain that were evaluated by applying classifications from scientific literature. Currently, the majority of the studied quarry lakes may be defined as mesotrophic or eutrophic according to the trophic state classifications. Based on historic data, lake trophic levels have increased over time, during active mining. At the end of mining activity, further deterioration of water quality was expected, especially for smaller lakes with minimal oxygen stratification and higher levels of nutrients and algal growth. In addition, the paper focuses on the pit lake water quality and pit dimension; From an environmental perspective the excavation of quarry lakes with an appreciable size will likely result in a better safeguard of water quality and enhanced possibilities for lake end use after the cessation of mining. Piedmont quarry

  18. Application of the dating by fission tracks to determine thermicity of basins within petroleum potentialities: example of Sbaa and Ahnet-North basins located in Western Saharan platform, Algeria; Application de la datation par traces de fission a l'analyse de la thermicite de bassins a potentialites petrolieres: exemple de la cuvette de Sbaa et du bassin de l'Ahnet-Nord (plate-forme saharienne occidentale, Algerie)

    Energy Technology Data Exchange (ETDEWEB)

    Akkouche, M

    2007-05-15

    The interpretation of old fundamental research works and the results obtained by this study based on: the analysis of apatite fission tracks (AFT), the burial evolution curves and the sequential analysis of outcrop section, as well as the curves of signal of gamma ray (GR) analysis from drilling wells, allow to precise that the geodynamic evolution of the studied Algerian sedimentary basins (Ahnet and Sbaa) have been occurred principally in the Paleozoic era. The analysis of burial evolution curves shows that during the Paleozoic period, the sedimentation is controlled by the tectonic subsidence, particularly at the end of Carboniferous in the favor of Ougarta folding. The curves indicate an uplift from the Permian to middle Jurassic, expressed by an important erosion of sedimentary series and is considered as a response of thermal convection of the Saharan platform followed by thermal subsidence. This can be explained by the halt motion of rift extension caused by the opening of the Atlantic Ocean. To bring the sequential analysis out, it appears that Ahnet and Sbaa basins present contrasted stratigraphic recordings, so much in time than in space, indicated the different effects from subsidence and erosions according to their sectors. In thermal point of view, temperatures are still moderate in Sbaa depression and favorite the preservation of organic matter and might generate hydrocarbons until now. However, these conditions are not similar to ones in the case of Ahnet basin. In the North part of Ahnet basin (MRS-1, MSL-1), the ages are around 50 Ma, attested that sedimentary layers have been sustained a post-Hercynian thermal phase. This phase could be estimated probably more than 100 C. This is also produced during the regional extension of the Triassic-Jurassic rifting. This episode could also be responsible of disappearance (total?) of pre-existence fission tracks in the Devonian layers of the well MSR-1, which exhibits at the depth 505 m under the Hercynian

  19. Recent population size, trends, and limiting factors for the double-crested Cormorant in Western North America

    Science.gov (United States)

    Adkins, Jessica Y.; Roby, Daniel D.; Lyons, Donald E.; Courtot, Karen N.; Collis, Ken; Carter, Harry R.; Shuford, W. David; Capitolo, Phillip J.

    2014-01-01

    The status of the double-crested cormorant (Phalacrocorax auritus) in western North America was last evaluated during 1987–2003. In the interim, concern has grown over the potential impact of predation by double-crested cormorants on juvenile salmonids (Oncorhynchusspp.), particularly in the Columbia Basin and along the Pacific coast where some salmonids are listed for protection under the United States Endangered Species Act. Recent re-evaluations of double-crested cormorant management at the local, flyway, and federal level warrant further examination of the current population size and trends in western North America. We collected colony size data for the western population (British Columbia, Washington, Oregon, Idaho, California, Nevada, Utah, Arizona, and the portions of Montana, Wyoming, Colorado and New Mexico west of the Continental Divide) by conducting aircraft-, boat-, or ground-based surveys and by cooperating with government agencies, universities, and non-profit organizations. In 2009, we estimated approximately 31,200 breeding pairs in the western population. We estimated that cormorant numbers in the Pacific Region (British Columbia, Washington, Oregon, and California) increased 72% from 1987–1992 to circa 2009. Based on the best available data for this period, the average annual growth rate (λ) of the number of breeding birds in the Pacific Region was 1.03, versus 1.07 for the population east of the Continental Divide during recent decades. Most of the increase in the Pacific Region can be attributed to an increase in the size of the nesting colony on East Sand Island in the Columbia River estuary, which accounts for about 39% of all breeding pairs in the western population and is the largest known breeding colony for the species (12,087 breeding pairs estimated in 2009). In contrast, numbers of breeding pairs estimated in coastal British Columbia and Washington have declined by approximately 66% during this same period. Disturbance at breeding

  20. Anatomy of a rift system: Triassic-Jurassic basins of eastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Schlische, R.W. (Rutgers Univ., New Brunswick, NJ (United States)); Olsen, P.E. (Columbia Univ., Palisades, NY (United States))

    1991-03-01

    Basins containing the early Mesozoic Newark Supergroup formed during the incipient rifting of Pangaea. The basins are characterized by the following: (1) The border fault systems (BFS) represent reactivated older faults. (2) A regionally persistent northwest-southeast to west-northeast-east-southeast extension direction reactivated northeast- to north-striking structures as predominantly normal dip-slip faults. (3) The half-grabens are lozenge-shaped basins in which subsidence-fault slip was greatest at or near the center of the BFS and decreased to zero toward either end. (4) Transverse folds in the hanging walls immediately adjacent to the BFS formed as a result of higher-frequency variations in subsidence. (5) Subsidence also decreased in a direction perpendicular to the BFS. (6) Intrabasinal faults are overwhelmingly synthetic and predominantly post-depositional. (7) Younger strata progressively onlap prerift rocks of the hanging wall block; this indicates that the basins grew both in width and length as they filled. (8) In all basins initial sedimentation was fluvial, reflecting an oversupply of sediment with respect to basin capacity. (9) Sediments were derived largely from the hanging wall block, which sloped toward the basin, and from streams that entered the basin axially; a direct footwall source was minor, owing to footwall uplift. (10) In strike-slip-dominated basins, subsidence was considerably less than in dip-slip basins, and mosaics of strike- and dip-slip faults are common.

  1. Statistical Aspects of the North Atlantic Basin Tropical Cyclones: Trends, Natural Variability, and Global Warming

    Science.gov (United States)

    Wilson, Robert M.

    2007-01-01

    Statistical aspects of the North Atlantic basin tropical cyclones for the interval 1945- 2005 are examined, including the variation of the yearly frequency of occurrence for various subgroups of storms (all tropical cyclones, hurricanes, major hurricanes, U.S. landfalling hurricanes, and category 4/5 hurricanes); the yearly variation of the mean latitude and longitude (genesis location) of all tropical cyclones and hurricanes; and the yearly variation of the mean peak wind speeds, lowest pressures, and durations for all tropical cyclones, hurricanes, and major hurricanes. Also examined is the relationship between inferred trends found in the North Atlantic basin tropical cyclonic activity and natural variability and global warming, the latter described using surface air temperatures from the Armagh Observatory Armagh, Northern Ireland. Lastly, a simple statistical technique is employed to ascertain the expected level of North Atlantic basin tropical cyclonic activity for the upcoming 2007 season.

  2. Tectonic and stratigraphic evolution of the Western Alboran Sea Basin in the last 25 Myrs

    Science.gov (United States)

    Do Couto, Damien; Gorini, Christian; Jolivet, Laurent; Lebret, Noëmie; Augier, Romain; Gumiaux, Charles; d'Acremont, Elia; Ammar, Abdellah; Jabour, Haddou; Auxietre, Jean-Luc

    2016-05-01

    The Western Alboran Basin (WAB) formation has always been the subject of debate and considered either as a back-arc or a forearc basin. Stratigraphic analyses of high-resolution 2D seismic profiles mostly located offshore Morocco, enabled us to clarify the tectonic and stratigraphic history of the WAB. The thick pre-rift sequence located beneath the Miocene basin is interpreted as the topmost Malaguide/Ghomaride complex composing the Alboran domain. The structural position of this unit compared with the HP-LT exhumed Alpujarride/Sebtide metamorphic basement, leads us to link the Early Miocene subsidence of the basin with an extensional detachment. Above the Early Miocene, a thick Serravallian sequence marked by siliciclastic deposits is nearly devoid of extensional structures. Its overall landward to basinward onlap geometry indicates that the WAB has behaved as a sag basin during most of its evolution from the Serravallian to the late Tortonian. Tectonic reconstructions in map view and in cross section further suggest that the basin has always represented a strongly subsiding topographic low without internal deformation that migrated westward together with the retreating slab. We propose that the subsidence of the WAB was controlled by the pull of the dipping subducting lithosphere hence explaining the considerable thickness (10 km) of the mostly undeformed sedimentary infill.

  3. Terrestrial pollution in the Pechora basin, north-eastern European Russia

    OpenAIRE

    Walker, Tony Robert

    2003-01-01

    The chemical composition of snow, terricolous lichens and top-soil along with abundance and diversity of lichen communities were assessed in the Pechora and Usa basins, North-Eastern European Russia. Transects were established through the principal industrial towns of Vorkuta, Inta and Usinsk to assess the spatial extent of acid or alkaline and metal deposition. A further eight sites were selected to assess local impacts of oil and gas operations. In the Usa basin decreases of nitrogen co...

  4. Tracking regional and global teleconnections recorded by western North American speleothem records

    Science.gov (United States)

    Oster, Jessica L.; Kelley, Neil P.

    2016-10-01

    Speleothem proxy records are useful for interrogating past climates in the low and mid-latitudes given their ability to provide continuous, high-resolution, and long-lived records that can be dated with high precision. Several speleothem oxygen isotope records from western North America have recently been developed that highlight the importance of this archive in documenting past changes in atmospheric circulation. Taken individually, these records hint at teleconnections between western North American hydroclimate and climate changes in the high northern latitudes and tropics. However, there has been no systematic investigation of global climate teleconnections to this region that draws upon the body of North American speleothem records as a whole. Here we review the dominant controls on precipitation oxygen isotopes across the region, and conduct statistical comparisons and network visualizations of high-resolution speleothem oxygen isotope records from western North America to investigate the regional response to pronounced climate changes of the last deglaciation and to determine the pattern of global teleconnections to this region. We find that most western North American speleothem oxygen isotope records demonstrate a robust and consistent response to the events of the last deglaciation, despite differing controls on the oxygen isotope ratio of precipitation across the region. One record that receives a strong influence from the Gulf of Mexico exhibits a contrasting pattern in oxygen isotopes relative to most of the other records, which are dominated by westerly storms generated in the Pacific. During the studied interval, major shifts in Western North American speleothem records appear broadly synchronous at least within the uncertainty of age models. We also find strong statistical linkages between western North American speleothem records and speleothem records of Asian monsoon variability and other records from regions directly influenced by movement of

  5. North Atlantic Basin Tropical Cyclone Activity in Relation to Temperature and Decadal- Length Oscillation Patterns

    Science.gov (United States)

    Wilson, Robert M.

    2009-01-01

    Yearly frequencies of North Atlantic basin tropical cyclones, their locations of origin, peak wind speeds, average peak wind speeds, lowest pressures, and average lowest pressures for the interval 1950-2008 are examined. The effects of El Nino and La Nina on the tropical cyclone parametric values are investigated. Yearly and 10-year moving average (10-yma) values of tropical cyclone parameters are compared against those of temperature and decadal-length oscillation, employing both linear and bi-variate analysis, and first differences in the 10-yma are determined. Discussion of the 2009 North Atlantic basin hurricane season, updating earlier results, is given.

  6. Skill evaluation of water supply forecasts in western Sierra Nevada and Colorado River basins

    OpenAIRE

    Harrison, Brent

    2014-01-01

    Runoff records from thirteen major river basins on the western slope of the Sierra Nevada in California were compared to runoff forecasts for those watersheds to determine the skill of those runoff forecasts. The forecasts, some dating back to the 1930's, were made at the beginning of the months of February, March, April and May. An array of summary, correlation and categorical skill measures were computed for each forecast and associated observation. The same array of skill measures were c...

  7. Lunar impact basins and crustal heterogeneity - New western limb and far side data from Galileo

    Science.gov (United States)

    Belton, Michael J. S.; Head, James W., III; Pieters, Carle M.; Greeley, Ronald; Mcewen, Alfred S.; Neukum, Gerhard; Klaasen, Kenneth P.; Anger, Clifford D.; Carr, Michael H.; Chapman, Clark R.

    1992-01-01

    Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (greater than 2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta.

  8. XXI Century Climatology of Snow Cover for the Western River Basins of the Indus River System

    CERN Document Server

    Hasson, Shabeh ul; Lucarini, Valerio

    2012-01-01

    Under changing climate, freshwater resources of Hindu Kush-Karakoram-Himalaya (HKH) region can be affected by changes in temperature and in amount, type and distribution of precipitation. This can have serious implications for the water supply and in turn threaten the food security and economic wellbeing of Indus basin. Using MODIS daily snow products (Terra & Aqua), this study focuses on the assessment of the 2000-2010 snow cover dynamics on seasonal/annual basis against geophysical parameters (aspect, elevation and slope) for the so called western river basins of Indus River System (IRS), namely Indus, Kabul, Jhelum, Astore, Gilgit, Hunza, Swat, Shigar and Shyok basins. Results show that inputs from MODIS instrument provide unprecedented better opportunity to study by using GIS techniques the snow cover dynamics in the remote areas like HKH region at such hyper-temporal and finer planar resolution. Adapted non-spectral cloud filtering techniques have significantly reduced cloud coverage and improved sno...

  9. On cold spells in North America and storminess in western Europe

    Science.gov (United States)

    Messori, Gabriele; Caballero, Rodrigo; Gaetani, Marco

    2016-06-01

    We discuss the dynamical and statistical links between cold extremes over eastern North America and storminess over western Europe, with a focus on the midlatitude jet stream, the North Atlantic Oscillation (NAO) and the Pacific-North American Pattern (PNA). The analysis is performed on the European Centre for Medium-Range Weather Forecasts 20th Century Reanalysis. The large-scale circulation associated with the cold spells corresponds to advection of cold air from the Arctic region into North America and to a very zonal and intense North Atlantic jet, shifted persistently south of its climatological location. These features of the Atlantic jet are conducive to destructive windstorms and intense precipitation over a large part of southern and continental Europe and the British Isles. The cold spells are preceded by a negative NAO and followed by a positive PNA; however, we interpret the associated circulation anomalies as being distinct from these standard modes of climate variability.

  10. Geochemistry of Brines from Salt Ore Deposits in Western Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    马万栋; 马海州; 谭红兵; 董亚萍; 张西营; 孙国芳

    2004-01-01

    In the geological evolution of the Tarim Basin, many transgressions and relictions happened. So there have been plentiful sources of salt. Moreover, because of uttermost drought, a lot of salt has been deposited. It is possible to find potash salt in this area. In our fieldwork, we have found salt and brine in western Tarim Basin. Based on a geological survey and the characteristics of sedimentary facies and paleogeography, this paper deals with the geochemical parameters and discusses the possibility of formation of potash salt in terms of the chemical analyses of samples collected from western Tarim Basin. Results of brine analysis lead to some conclusions: most of these salt brines have eluviated from very thick halite beds, mainly chloride-type salt and this kind of halite does not reach the stage of potash deposition in all aspects; WKSL (Wukeshalu) occupies a noticeable place, and we should attach importance to this district because there have been some indicators of the occurrence of potash deposits as viewed from the contents of Br and K. Finally, low Br contents are recognized in the Tarim Basin as a result of salt aggradation, and this point of view has been proved by the results of this experiment and the data available. It cannot depend upon the index of Br to judge the evolution stage of halite. We must look for other facies of potash except marine facies.

  11. Survival of non-Western first generations immigrants with stomach cancer in North East Netherlands

    NARCIS (Netherlands)

    Siemerink, E. J. M.; van der Aa, M. A.; Siesling, S.; Hospers, G. A. P.; Mulder, N. H.

    2011-01-01

    BACKGROUND: Isolated groups, such as first generation non-Western immigrants, are at risk for suboptimal utilisation of the health care system resulting in a worse outcome. METHODS: From 1989 to 2007, all patients with stomach cancer were selected from the Comprehensive Cancer Centre North-East canc

  12. Assessing malaria transmission in a low endemicity area of north-western Peru

    DEFF Research Database (Denmark)

    Rosas-Aguirre, Angel; Llanos-Cuentas, Alejandro; Speybroeck, Niko;

    2013-01-01

    Where malaria endemicity is low, control programmes need increasingly sensitive tools for monitoring malaria transmission intensity (MTI) and to better define health priorities. A cross-sectional survey was conducted in a low endemicity area of the Peruvian north-western coast to assess the MTI...

  13. Whales, Dolphins, and Porpoises of the Western North Atlantic: A Guide to Their Identification.

    Science.gov (United States)

    Leatherwood, Stephen; And Others

    This field guide is designed to permit observers to identify the cetaceans (whales, dolphins, and porpoises) they see in western North Atlantic, including the Caribbean Sea, the Gulf of Mexico, and the coastal waters of the United States and Canada. The animals described are not grouped by scientific relationships but by similarities in appearance…

  14. MIGRATORY DEPARTURES OF WADERS FROM NORTH-WESTERN AUSTRALIA - BEHAVIOR, TIMING AND POSSIBLE MIGRATION ROUTES

    NARCIS (Netherlands)

    Tulp, Ingrid; MCCHESNEY, S; DEGOEIJ, P

    1994-01-01

    Migratory activity of waders departing from north-western Australia in March-April 1991 was recorded by field observations and radar tracking. Field observations showed that the species concerned were mainly Bar-tailed Godwit Limosa lapponica, Grey Plover Pluvialis squatarola and Great Knot Calidris

  15. HIV-INFECTION IN THE NORTH-WESTERN FEDERAL REGION OF THE RUSSIAN FEDERATION IN 2009

    Directory of Open Access Journals (Sweden)

    T. T. Smolskaya

    2011-01-01

    Full Text Available Abstract. In the current review the results of HIV surveillance in 11 administrative territories of the North-western federal region of the Russian Federation (NWFR in 2009 are summarized. The analysis of epidemic process is based on the data of HIV cases detected in the administrative territories of the NWFR by serological screening and registered in the state reporting forms.

  16. Spatial trends of polyfluorinated compounds in guillemot (Uria aalge) eggs from North-Western Europe

    DEFF Research Database (Denmark)

    Löfstrand, Karin; Jörundsdóttir, Hrönn; Tomy, Gregg;

    2008-01-01

    carboxylic acids (PFCAs) in guillemot (Uria aalge) eggs, collected in North-Western Europe, from Iceland, the Faroe Islands, Sweden and two locations in Norway. The highest concentrations of PFOS were found in samples from Sweden (mean 400 ng g(-1) wet weight (w.w.)), which were almost five times higher than...

  17. Changing climate-changing pathogens: Toxoplasma gondii in North-Western Europe

    NARCIS (Netherlands)

    Meerburg, B.G.; Kijlstra, A.

    2009-01-01

    In this review, we describe the effects of global climate change for one specific pathogen: the parasite Toxoplasma gondii. It is postulated that an increase of T. gondii prevalence in humans can occur in some regions of North-Western Europe as a result of changing environmental conditions. Such a c

  18. Interbasinal marker intervals——A case study from the Jurassic basins of Kachchh and Jaisalmer, western India

    Institute of Scientific and Technical Information of China (English)

    PANDEY; Dhirendra; Kumar; FüRSICH; Franz; Theodor

    2009-01-01

    The Kachchh Basin and the Jaisalmer Basin are two neighboring Mesozoic sedimentary basins at the western margin of the Indian craton. The Jurassic succession of the Kachchh Basin is more complete and more fossiliferous than that of the Jaisalmer Basin. Consequently, intrabasinal correlation of the sedimentary units has been possible in the Kachchh Basin, but not in the Jaisalmer Basin. However, some marker beds existing in the Kachchh Basin can be recognized also in the Jaisalmer Basin. Ammonite evidence shows that they are time-equivalent. The following four units form marker intervals in both basins: (1) the pebbly rudstone unit with Isastrea bernardiana and Leptosphinctes of the Kaladongar Formation (Kachchh Basin) and the Isastrea bernardiana-bearing rudstone of the Jaisalmer Formation (Jaisalmer Basin) both represent transgressive systems tract deposits dated as Late Bajocian; (2) bioturbated micrites with anomalodesmatan bivalves within the Goradongar Yellow Flagstone Member (Kachchh Basin) and bioturbated units in the Fort Member (Jaisalmer Basin) represent maximum flooding zone deposits of the Middle to Late Bathonian; (3) trough-crossbedded, sandy packto grainstones of the Raimalro Limestone Member (Kachchh Basin) and the basal limestone-sandstone unit of the Kuldhar section of the Jaisalmer Formation (Jaisalmer Basin) correspond to Late Bathonain transgressive systems tract deposits; and (4) ferruginous ooid-bearing carbonates with hardgrounds of the Dhosa Oolite member (Kachchh Basin) and the middle part of the Jajiya Member (Jaisalmer Basin) are Oxfordian transgressive systems tract deposits. The fact that in both basins similar biofacies prevailed during certain time intervals demonstrates a common control of their depositional history. As the two basins represent different tectonic settings, the most likely controlling factors were the relative sea-level changes produced by eustatic processes, a common subsidence history of the northwestern margin of

  19. Variety, State and Origin of Drained Thaw Lake Basins in West-Siberian North

    Science.gov (United States)

    Kirpotin, S.; Polishchuk, Y.; Bryksina, N.; Sugaipova, A.; Pokrovsky, O.; Shirokova, L.; Kouraev, A.; Zakharova, E.; Kolmakova, M.; Dupre, B.

    2009-04-01

    Drained thaw lake basins in Western Siberia have a local name "khasyreis" [1]. Khasyreis as well as lakes, ponds and frozen mounds are invariable element of sub-arctic frozen peat bogs - palsas and tundra landscapes. In some areas of West-Siberian sub-arctic khasyreis occupy up to 40-50% of total lake area. Sometimes their concentration is so high that we call such places ‘khasyrei's fields". Khasyreis are part of the natural cycle of palsa complex development [1], but their origin is not continuous and uniform in time and, according to our opinion, there were periods of more intensive lake drainage and khasyrei development accordingly. These times were corresponding with epochs of climatic warming and today we have faced with one of them. So, last years this process was sufficiently activated in the south part of West-Siberian sub-arctic [2]. It was discovered that in the zone of continuous permafrost thermokarst lakes have expanded their areas by about 10-12%, but in the zone of discontinuous permafrost the process of their drainage prevails. These features are connected with the thickness of peat layers which gradually decreases to the North, and thus have reduced the opportunity for lake drainage in northern areas. The most typical way of khasyrei origin is their drainage to the bigger lakes which are always situated on the lower levels and works as a collecting funnels providing drainage of smaller lakes. The lower level of the big lake appeared when the lake takes a critical mass of water enough for subsidence of the lake bottom due to the melting of underlaying rocks [2]. Another one way of lake drainage is the lake intercept by any river. Lake drainage to the subsurface (underlaying rocks) as some authors think [3, 4] is not possible in Western Siberia, because the thickness of permafrost is at list 500 m here being safe confining bed. We mark out few stages of khasyrei development: freshly drained, young, mature and old. This row reflects stages of

  20. On the Origin of One Basin-Multiple Mountain Couplings in the Mesozoic-Cenozoic Basin-Range Area in Eastern North China

    Institute of Scientific and Technical Information of China (English)

    NIU Shuyin; SHAO Ji'an; HOU Quanlin; WANG Baode; XU Chuanshi

    2004-01-01

    The basin-range coupling relation is a leading subject of the modern geology. In geometry, relations of this type include couplings between stretched orogenic belt and down-faulted basin, compressional orogenic belt and foreland basin, strike-slip orogenic belt and strike-slip basin and so on. Fault chains are the key for these couplings and there are typical examples for all these cases. The North China down-faulted basin is coupled west with the Tathang uplift, east with the Jiao-Liao Mountains, north with the Yanshan orogenic belt and south with the Dabie orogenic belt,that is to say, the central down-faulted basin and the surrounding orogenic belts bear a coupling relation within a uniform dynamistic system. Study shows that the central down-faulted basin and the North China mantle sub-plume structure have a close relation during their formation. Owing to intensive mantle sub-plume uplifting, the bottom of the lithosphere suffered from resistance, which caused the lithosphere of the eastern North China to be heated, thinned and fault-depressed. Meanwhile, mantle rocks that were detached outwards in the shape of mushroom was dissected by surrounding ductile shearing zones, which lead to decompression and unloading to generate hypomagmas, and a series of mantle-branch structures were formed around the down-faulted basin. There is an obvious comparability among these mantle branch structures (orogenic belts), and they have basin-range coupling relations with the central down-faulted basins.

  1. Possible relationship between East Asian summer monsoon and western North Pacific tropical cyclone genesis frequency

    Science.gov (United States)

    Choi, Ki-Seon; Cha, Yumi; Kim, Hae-Dong; Kang, Sung-Dae

    2016-04-01

    In the present study, the fact that strong positive correlations have existed between East Asian summer monsoons (EASMs) and western North Pacific tropical cyclone (TC) genesis frequency over the last 37 years was found. To figure out the cause of these correlations, 7 years (positive East Asian summer monsoon index (EASMI) phase) that have the highest values and 7 years (negative EASMI phase) that have the lowest values in the normalized EASM index were selected and the differences in averages between the two phases were analyzed. In the positive EASMI phase, TCs mainly occurred in the northwestern waters of the tropical and subtropical western North Pacific and showed a tendency to move from the far eastern waters of the Philippines, pass the East China Sea, and move northward toward Korea and Japan. On the 500 hPa streamline, whereas anomalous anticyclones developed in the East Asia middle-latitude region, anomalous cyclones developed in the tropical and subtropical western North Pacific. Therefore, in this phase, whereas EASMs were weakened, western North Pacific summer monsoons (WNPSMs) were strengthened so that some more TCs could occur. In addition, in the case of the East China Sea and the southern waters of Japan located between the two anomalous pressure systems, TCs could move some more toward the East Asia middle-latitude region in this phase. According to an analysis of the 850 hPa relative vorticity, negative anomalies were strengthened in the East Asia middle-latitude region while positive anomalies were strengthened in the region south to 25 N. Therefore, in the positive EASMI phase, whereas EASMs were weakened, WNPSMs were strengthened so that some more TCs could occur. According to an analysis of the 850 and 200 hPa horizontal divergence, whereas anomalous downward flows were strengthened in the East Asia middle-latitude region, anomalous upward flows were strengthened in the tropical and subtropical western North Pacific. According to an analysis

  2. First detection of bat white-nose syndrome in western North America

    Science.gov (United States)

    Lorch, Jeffrey M.; Palmer, Jonathan M.; Lindner, Daniel L.; Ballmann, Anne; George, Kyle; Griffin, Kathryn M.; Knowles, Susan N.; Huckabee, John R; Haman, Katherine H; Anderson, Christopher D.; Becker, Penny A; Buchanan, Joseph B.; Foster, Jeffrey T.; Blehert, David

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused byPseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction ofP. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation.

  3. Relationship between the Antarctic oscillation in the western North Pacific typhoon frequency

    Institute of Scientific and Technical Information of China (English)

    WANG HuiJun; FAN Ke

    2007-01-01

    Relationship between the Antarctic oscillation (AAO) and the western North Pacific typhoon number (WNPTN) in the interannual variability is examined in this research. The WNPTN is correlated with the AAO in June-July-August-September (JJAS) in 1949-1998 at -0.48 for the detrended time series, statistically significant at 99% level. The tropical atmospheric circulation as well as the sea surface temperature variability over the western Pacific associated with AAO has been analyzed. It follows that a positive phase of JJAS AAO corresponds to the larger magnitude of the vertical zonal wind shear, the anomalous low-lever anti-cyclonic circulation and anomalous high-level cyclonic circulation, and lower sea surface temperature in the major typhoon genesis region in the western North Pacific, thus providing unfavorable environment for the typhoon genesis, and vice versa.

  4. The role of inherited crustal structures and magmatism in the development of rift segments: Insights from the Kivu basin, western branch of the East African Rift

    Science.gov (United States)

    Smets, Benoît; Delvaux, Damien; Ross, Kelly Ann; Poppe, Sam; Kervyn, Matthieu; d'Oreye, Nicolas; Kervyn, François

    2016-06-01

    The study of rift basin's morphology can provide good insights into geological features influencing the development of rift valleys and the distribution of volcanism. The Kivu rift segment represents the central section of the western branch of the East African Rift and displays morphological characteristics contrasting with other rift segments. Differences and contradictions between several structural maps of the Kivu rift make it difficult to interpret the local geodynamic setting. In the present work, we use topographic and bathymetric data to map active fault networks and study the geomorphology of the Kivu basin. This relief-based fault lineament mapping appears as a good complement for field mapping or mapping using seismic reflection profiles. Results suggest that rifting reactivated NE-SW oriented structures probably related to the Precambrian basement, creating transfer zones and influencing the location and distribution of volcanism. Both volcanic provinces, north and south of the Kivu basin, extend into Lake Kivu and are connected to each other with a series of eruptive vents along the western rift escarpment. The complex morphology of this rift basin, characterized by a double synthetic half-graben structure, might result from the combined action of normal faulting, magmatic underplating, volcanism and erosion processes.

  5. Preliminary result of dissolved organic radiocarbon in the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takayuki, E-mail: tanaka.takayuki@jaea.go.j [AMS Management Section, Japan Atomic Energy Agency, 4-24 Minatomachi, Mutsu, Aomori 035-0064 (Japan); Otosaka, Shigeyoshi [Research Group for Environmental Science, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan); Wakita, Masahide [Mutsu Institute for Oceanography, Japan Agency for Marine-Earth Science and Technology, 690 Kitasekine, Sekine, Mutsu, Aomori 035-0022 (Japan); Amano, Hikaru [Japan Chemical Analysis Center, 293-5 Sanno-cho, Inage-ku, Chiba-shi 263-0002 (Japan); Togawa, Orihiko [Research Group for Environmental Science, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan)

    2010-04-15

    Radiocarbon in dissolved organic matter in seawater gives information on the dynamics and origin of the dissolved organic matter. Here, we present the vertical profile of DELTA{sup 14}C of dissolved organic carbon in the western North Pacific Ocean. The profile was almost parallel to that for DELTA{sup 14}C of dissolved inorganic carbon, indicating that the time scale of seawater circulation was the main influence on the DELTA{sup 14}C signature of dissolved organic carbon. On the basis of the DELTA{sup 14}C differences between dissolved organic carbon and dissolved inorganic carbon, and a comparison with DELTA{sup 14}C of dissolved organic carbon in the central North Pacific Ocean, we suggest that there may be a source of younger dissolved organic carbon in the western North Pacific Ocean.

  6. Climate inferences between paleontological, geochemical, and geophysical proxies in Late Pleistocene lacustrine sediments from Summer Lake, Oregon, western Great Basin

    Science.gov (United States)

    Heaton, Eric; Thompson, Greg; Negrini, Rob; Wigand, Peter

    2016-04-01

    increases in discharge. This may suggest a short-lived interstadial period in which: 1) characteristic plant species did not have enough time to migrate and flourish to record increases in the pollen record or carbon/nitrogen ratio and 2) lake size did not have enough time to increase comparably to record significant grainsize changes. With the exception of interstadial 6, these results confirm those of earlier studies at Summer lake and other Great Basin lakes in western North America with respect to the relationship between millennial-scale temperature changes throughout the northern hemisphere and the response of regional climate in western North America at semitropical latitudes.

  7. Mesoscale cyclogenesis over the western north Pacific Ocean during TPARC

    Directory of Open Access Journals (Sweden)

    Christopher A. Davis

    2013-01-01

    Full Text Available Three cases of mesoscale marine cyclogenesis over the subtropics of the Western Pacific Ocean are investigated. Each case occurred during the THORPEX Pacific Asia Regional Campaign and Tropical Cyclone Structure (TCS-08 field phases in 2008. Each cyclone developed from remnants of disturbances that earlier showed potential for tropical cyclogenesis within the tropics. Two of the cyclones produced gale-force surface winds, and one, designated as a tropical cyclone, resulted in a significant coastal storm over eastern Japan. Development was initiated by a burst of organized mesoscale convection that consolidated and intensified the surface cyclonic circulation over a period of 12–24 h. Upper-tropospheric potential vorticity anomalies modulated the vertical wind shear that, in turn, influenced the periods of cyclone intensification and weakening. Weak baroclinicity associated with vertical shear was also deemed important in organizing mesoscale ascent and the convection outbreaks. The remnant tropical disturbances contributed exceptional water vapour content to higher latitudes that led to strong diabatic heating, and the tropical remnants contributed vorticity that was the seed of the development in the subtropics. Predictability of these events more than three days in advance appears to be minimal.

  8. Literature and information related to the natural resources of the North Aleutian Basin of Alaska.

    Energy Technology Data Exchange (ETDEWEB)

    Stull, E.A.; Hlohowskyj, I.; LaGory, K. E.; Environmental Science Division

    2008-01-31

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant natural resources. The Basin includes most of the southeastern part of the Bering Sea Outer Continental Shelf, including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals, including several federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, 'Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012' and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory were contracted to assist MMS with identifying and prioritizing information needs related to potential future oil and gas leasing and development activities in the North Aleutian Basin. Argonne focused on three related tasks: (1) identify and gather relevant literature published since 1996, (2) synthesize and

  9. The Geohydrology of MVT-Ore Genesis in the Canning Basin, Western Australia

    Science.gov (United States)

    Garven, G.; Wallace, M. M.

    2009-05-01

    In the Lennard Shelf, Western Australia, epigenetic MVT-type Pb-Zn mineralization occurs in Middle Devonian evaporitic dolomites which were part of a barrier reef system (Hurley & Lohmann, 1989). Ore mineralization exhibits a strong structural control at the basin scale and normal faults probably controlled pathways for brine and petroleum migration that affected ore deposition (Wallace et al., 1999). For the Canning basin, finite element simulations show that compaction was the most important process for creating overpressures and driving basinal fluids in this thick extensional basin. Basinal fluids are shown to have been driven across the Fitzroy Trough through permeable and deeply buried Silurian-Ordovician aquifer units. The fluids then migrated upwards at rates of m/yr up during periods of episodic extension (Braun, 1992) where fluid flow was channeled by major normal fault zones like the Cadjebut and Pinnacles Faults. Reactive flow simulations test a petroleum-reservoir model for mineralization whereby metal-bearing brines mix with accumulated hydrocarbons (Anderson & Garven, 1987). The results show that compaction-driven flow, as proposed by Beales & Jackson (1966) and Jackson & Beales (1967), works rather well in this ore district--other mechanisms such as sealevel tidal pumping (Cathles, 1988) or topographic drive (Solomon & Groves, 1994) are more tenuous and really unnecessary from a mass transport or geohydrologic basis.

  10. Abnormal overpressure distribution and natural gas accumulation in foreland basins, Western China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Abnormal overpressure occurs in the foreland basins of Kuqa, South Junggar and West Sichuan in China. The pressure coefficients are high. Overpressure exists in wide areas and various strata. The layers of overpressure have a very close relationship with lithology, and the area of overpressure is controlled by the piedmont depression. The mechanisms of overpressure formation in the Kuqa and South Junggar Depression include disequilibrium compaction and tectonic compression; the importance of these two factors varies in different basins and in different stages of the same basin. Different models of gas accumulation are established to explain the relationship between overpressure distribution and gas pool formation, and the influence of overpressure on the gas pools. These models include: (ⅰ) the violent tectonic movement leads to the pool formation in overpressure belt (Kela-2 gas field in Kuqa); (ⅱ) the pressure releases at shallow part and the gas pool forms in late time (Hutubi gas field in southern Junggar Basin); (ⅲ) through the pressure transfer the gas migrates and accumulates (Xinchang gas field in Western Sichuan Basin).

  11. Review of the petroleum geology of the western part of the Sirt Basin, Libya

    Science.gov (United States)

    Abdunaser, K. M.

    2015-11-01

    The petroleum geology of the western part of the Sirt Basin is reviewed by source, reservoir, traps and seal type in addition to Oil migration by different mechanisms. In general the oil and gas accumulations within Sirt Basin are reservoired in granitic basement, sandstones and carbonates ranging in age from Pre-Cambrian to Oligocene, charged by syn and early postrift, Triassic and intra-Cretaceous organic rich lacustrine and restricted marine shales. This paper offers a broad overview on petroleum systems of the western Sirt Basin as a part of the complex, prolific and mature Sirt Basin which considered as one of tectonically active basins of Mesozoic-Cenozoic age in central northern Libya includes reviewing the potential source rocks and assesses their thermal maturity, petroleum generation potential, organic richness and distribution. Key factors responsible for hydrocarbon distribution described by source rock distribution maps, and hydrocarbon generation areas as well as stratigraphic distribution of oil and gas occurrences with field maps and cross-sections (analogues) and summary reservoir description have been shown. The oil to source correlation scheme suggests that most of the oil in the study area was derived from the Sirte Shale (Upper Cretaceous, Campanian/Turonian), whilst the reservoirs are ranging in age from Lower/Upper Cretaceous to the Eocene. Sandstones predominate in the Cretaceous and carbonates are the main reservoirs in the Tertiary. Several different play types have been described from the study area of the western part of the Sirt Basin dominated by the structural traps, which range from simple normal faults to more complex faults and fold structures associated with wrench faults. Structural traps are dominant in the Zallah Trough and are mainly related to Eocene deformation on the heavily faulted western side of the basin. In addition several types of stratigraphic traps are present in the study area and essentially they are

  12. Plio-Quaternary kinematic development and paleostress pattern of the Edremit Basin, western Turkey

    Science.gov (United States)

    Gürer, Ömer Feyzi; Sangu, Ercan; Özburan, Muzaffer; Gürbüz, Alper; Gürer, Aysan; Sinir, Hasan

    2016-06-01

    The Edremit Basin and Kazdağ High are the most prominent morphological features of the Biga Peninsula in northwest Anatolia. There is still no consensus on the formation of Edremit Basin and debates are on whether the basin evolved through a normal, a right-lateral or a left-lateral strike-slip faulting. In this study, the geometric, structural and kinematic characteristics of the Edremit Basin are investigated to make an analytical approach to this problem. The structural and kinematic features of the faults in the region are described according to field observations. These fault-slip data derived from the fault planes were analyzed to determine the paleostress pattern of faulting in the region. According to the performed analysis, the southern end of the Biga Peninsula is under the influence of the ENE-WSW-trending faults of the region, such as the Yenice-Gönen, the Edremit, the Pazarköy and the Havran-Balıkesir Fault Zones. The right step-over geometry and related extension caused to the development of the Edremit Basin as a transtensional pull-apart basin between the Havran-Balıkesir Fault Zone and the Edremit Fault Zone. Field observations showed that the Plio-Quaternary faults at the Edremit Gulf and adjacent areas are prominently right-lateral strike-slip faults. Our paleostress analyses suggest a dominant NE-SW extension in the study area, as well as NW-SE direction. This pattern indicates the major effects of the North Anatolian Fault System and the component of Aegean Extensional System in the region. However, our kinematic analysis represents the dominant signature of the North Anatolian Fault System in basin bounding faults. The field observations and kinematic findings of this study are also consistent with the regional GPS, paleomagnetic and seismological data. This study concludes that the North Anatolian Fault System is the prominent structure in the current morphotectonic framework of the Edremit Gulf and adjacent areas.

  13. The Mediterranean basin

    DEFF Research Database (Denmark)

    Tomas, Carmen; Sanchez Sanchez, Juan Jose; Barbaro, A.;

    2008-01-01

    genetically from the rest of the populations in the Mediterranean area. This result supports the hypothesis of a low incidence of the south-north genetic interchange at the western shores of the Mediterranean basin. A low genetic distance was found between populations in the Middle East and the western part...

  14. Predicting grizzly bear density in western North America.

    Directory of Open Access Journals (Sweden)

    Garth Mowat

    Full Text Available Conservation of grizzly bears (Ursus arctos is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  15. Predicting grizzly bear density in western North America.

    Science.gov (United States)

    Mowat, Garth; Heard, Douglas C; Schwarz, Carl J

    2013-01-01

    Conservation of grizzly bears (Ursus arctos) is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  16. The Role of Soil Water and Land Feedbacks in Decadal Drought in Western North America

    Science.gov (United States)

    Langford, S.; Chikamoto, Y.; Noone, D. C.

    2013-12-01

    Western North America is susceptible to severe impacts of megadroughts, as evidenced by tree-core or lake sediment records. Future predictions suggest that this region will become more arid, with further consequences for water resources. Understanding the mechanisms of drought variability and persistence in western North America is critical for the eventual development of effective forecasting methods. The ocean is expected to be the main source of decadal memory in the system as the atmosphere varies on a much shorter timescale. The ocean's role in driving the low-frequency variability of the system is potentially predictable. However, low-frequency precipitation anomalies in western North America can occur in the absence of ocean feedbacks. Sea surface temperature anomalies in the north Pacific Ocean only account for around 20 per cent of the low-frequency winter precipitation in California in the CMIP5 historical runs. This is not sufficient to use the skill of global coupled models in predicting ocean conditions ahead of time to successfully forecast the possibility of long-term drought in western North America. Megadroughts therefore may be generated by unpredictable atmospheric noise, or persisted by other sources of low-frequency variability such as land processes and feedbacks. Snowpack in western North America is a crucial water resource for the surrounding communities, storing the winter precipitation for use later in the year. Likewise, soil moisture integrates the precipitation signal; the time scale depends on the depth and characteristics of the soil. Water storage and related variables are more predictable on longer timescales than precipitation, as measured by anomaly correlation for hindcasts compared to a 'perfect model' control run with CESM1.0.3. The importance of antecedent land conditions in persisting megadroughts in western North America is explored with ensemble simulations of CESM1.0.3, where the atmosphere is perturbed at the initiation

  17. Basin Management under the Global Climate Change (Take North-East Asia Heilongjiang -Amur Basin and Taihu Basin For Example)

    Science.gov (United States)

    Liu, S.; Zhou, Z.; Zhong, G.; Zhang, X.

    2015-12-01

    The impact of global climate change on environment and society causes increasingly concern in different countries around the world. The main climate characteristic values, such as precipitation and temperature, have been changed, which leads to the variation of water resources, especially in large basins. Heilongjiang-Amur Basin and Taihu Basin are two large and important basins in China with large area and population. As global climate change and human activities have siganificant impacts on hydrology and water resources in two basins, the analysis of climate change are of great value. In this study, in Heilongjiang-Amur Basin, precipitation and temperature are investigated and their variation are predicted. And in Taihu Basin, precipitation including plum rain and typhoon, are studied and the variation trend of precipitation is predicted. Hence, the impacts of global climate change are assessed. From the result, it shows that the average temperature will continue to increase, and the precipitation will reduce first and then turn to increase in these two basins. It demonstrates that the water resources have been affected a lot by climate change as well as human activities. And these conclusions are provided as reference for policy makers and basin authorities in water resources management and natural hazards mitigation. Meanwhile, according to basins' particualr characters, the suggestions to future water resources management in two basins are given, and more scientific, comprehensive and sustained managements are required. Especially, in Heilongjiang-Amur River, which is a boundary river between China and Russia, it is very essential to enhance the cooperation between two countries.

  18. Assessment of undiscovered oil and gas resources of the North Sakhalin Basin Province, Russia, 2011

    Science.gov (United States)

    Klett, T.R.; Schenk, Christopher J.; Wandrey, Craig J.; Charpentier, Ronald R.; Brownfield, Michael E.; Pitman, Janet K.; Pollastro, Richard M.; Cook, Troy A.; Tennyson, Marilyn E.

    2011-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated volumes of undiscovered, technically recoverable, conventional petroleum resources for the North Sakhalin Basin Province of Russia. The mean volumes were estimated at 5.3 billion barrels of crude oil, 43.8 trillion cubic feet of natural gas, and 0.8 billion barrels of natural gas liquids.

  19. Genetic diversity, endemism and phylogeny of lampreys within the genus Lampetra sensu stricto (Petromyzontiformes: Petromyzontidae) in western North America.

    Science.gov (United States)

    Boguski, D A; Reid, S B; Goodman, D H; Docker, M F

    2012-11-01

    Phylogenetic structure of four Lampetra species from the Pacific drainage of North America (western brook lamprey Lampetra richardsoni, Pacific brook lamprey Lampetra pacifica, river lamprey Lampetra ayresii and Kern brook lamprey Lampetra hubbsi) and unidentified Lampetra specimens (referred to as Lampetra sp.) from 36 locations was estimated using the mitochondrial cytochrome b gene. Maximum parsimony and Bayesian inferences did not correspond with any taxonomic scheme proposed to date. Rather, although L. richardsoni (from Alaska to California) and L. ayresii (from British Columbia to California) together constituted a well-supported clade distinct from several genetically divergent Lampetra populations in Oregon and California, these two species were not reciprocally monophyletic. The genetically divergent populations included L. pacifica (from the Columbia River basin) and L. hubbsi (from the Kern River basin) and four Lampetra sp. populations in Oregon (Siuslaw River and Fourmile Creek) and California (Kelsey and Mark West Creeks). These four Lampetra sp. populations showed genetic divergence between 2.3 and 5.7% from any known species (and up to 8.0% from each other), and may represent morphologically cryptic and thus previously undescribed species. A fifth population (from Paynes Creek, California) may represent a range extension of L. hubbsi into the Upper Sacramento River. PMID:23130690

  20. Mechanism of petroleum migration and accumulation in western China's superposed basins

    Institute of Scientific and Technical Information of China (English)

    Kang Yongshang; Li Peijun; Qi Xuefeng; Wen Yonghong; Li Shuijing

    2012-01-01

    In western China.most petroliferous basins are superposed due to their multi-periodic tectonic evolution,and the mechanisms of petroleum migration and accumulation are so complex that much more sophisticated methodologies are necessary for depiction of these mechanisms and identification of petroleum occurrences.For this purpose,in this article,a new methodology was formulated which includes:(1) vertical identification of petroleum migration and accumulation fluid dynamic systems in the superposed basins;(2) analysis of the effect of large scale regional faults and fault combinations on the fluids exchange between the vertically identified different systems;(3) analysis of petroleum migration and accumulation in each vertically identified system,and establishment of appropriate geological model of petroleum migration and accumulation for each vertically identified system.Using this methodology,the satisfactory results obtained in the Lunnan Uplift of Tarim Basin and Ludong Uplift of Jungar Basin case studies are:(1) existence of different vertical fluid dynamic systems in western China's superposed basins which are very necessary for understanding the mechanism of petroleum migration and accumulation;(2) in deep system,long-distance lateral petroleum migration and accumulation mainly take place along the long time exposed unconformity with weathered,fractured or karst reservoir rocks;(3) regional faults are the main conducts for fluids migration from deep system up to middle and/or upper systems.As to middle and/or upper systems,regional faults play a role of "petroleum source".Small faults within middle and/or upper systems conduct petroleum to carrier beds with less impeding force;(4) petroleum migrated from deep system vertically up to middle and/or upper systems will migrate laterally in carrier beds of these systems and accumulate to form pools near or far from faults.

  1. Precambrian-Cambrian Sedimentology, Stratigraphy, and Paleontology in the Great Basin (Western United States)

    OpenAIRE

    Sappenfield, Aaron Dale

    2015-01-01

    Thick accumulations of Neoproterozoic and early Phanerozoic strata are distributed throughout much of the arid continental interior of western North America, providing an expansive and well-exposed archive of this important time in Earth’s history. The information presented herein supplements evaluations regarding the utility and limitations of this archive by providing an integrated sedimentological, paleontological, and geochronological description for Precambrian-Cambrian strata exposed i...

  2. Influence of Introgression and Geological Processes on Phylogenetic Relationships of Western North American Mountain Suckers (Pantosteus, Catostomidae)

    Science.gov (United States)

    Unmack, Peter J.; Dowling, Thomas E.; Laitinen, Nina J.; Secor, Carol L.; Mayden, Richard L.; Shiozawa, Dennis K.; Smith, Gerald R.

    2014-01-01

    Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus is one of several clades centered in this tectonically active region. The eight recognized Pantosteus species are widespread and common across southwestern Canada, western USA and into northern Mexico. They are typically found in medium gradient, middle-elevation reaches of rivers over rocky substrates. This study (1) compares molecular data with morphological and paleontological data for proposed species of Pantosteus, (2) tests hypotheses of their monophyly, (3) uses these data for phylogenetic inferences of sister-group relationships, and (4) estimates timing of divergence events of identified lineages. Using 8055 base pairs from mitochondrial DNA protein coding genes, Pantosteus and Catostomus are reciprocally monophyletic, in contrast with morphological data. The only exception to a monophyletic Pantosteus is P. columbianus whose mtDNA is closely aligned with C. tahoensis because of introgression. Within Pantosteus, several species have deep genetic divergences among allopatric sister lineages, several of which are diagnosed and elevated to species, bringing the total diversity in the group to 11 species. Conflicting molecular and morphological data may be resolved when patterns of divergence are shown to be correlated with sympatry and evidence of introgression. PMID:24619087

  3. Agroforestry in private land: a North Western Indian case study

    Energy Technology Data Exchange (ETDEWEB)

    Muhammed, Nur; Hague, Farhana; Koike, Masao (Forest Policy Laboratory, Department of Forest Science, Faculty of Agriculture, Shinshu University, Nagano (Japan))

    2007-07-01

    genetically superior clones. Timber yield of the Hara farm is 50 tons ha-1 year-1 (planting 500 trees ha-1; in 10 years rotation) where as the timber yield of the national forests is less than 1 5 ton hat year-1. It is reported that timber yield is 75 tons ha-1 year-1 with a rotation of 15-18 years. But wood industries of the region do not have equipments to handle the large size trees of 15-18 years. So they encourage only 6-8 years cycle. Therefore, the farmers loose this added income retaining trees for 15-18 years. This is also found that before 1990 there was no wood based industry there. Thereafter more than 600 wood processing factories developed in Haryana, Punjab, western Utter Pradesh and Uttarakand states of northern India. Out of this over 300 have been developed in the study area. This study identify that timber price fluctuation due to various socio-political factors hinders the development that during 1990-2000 timber price was US dollar 110 ton-1, dropped down to US dollar 20 ton-1 during 2001-2005 and now again there is an increase of price i.e. US dollar 125 ton-1 Finally, this type of tree based farming is so good for the farmers and farm economy and environmental improvement. More importantly it is notified that forests of the Haryana state has been increased from 3% (base year 1990) to 8 % (2006) which is a tremendous success. Hara Farm Being the largest one can afford anything to be required to sustain the practice. But for the average farms, government and NGO initiatives are needed to supply better clones, new knowledge, demonstration farm and monetary support during the peak farming seasons. It is suggested that if it is possible to establish a farmer led cooperatives, then from production and price point of view every stakeholder will be in a win-win situation. This farm is a model for education and it can be recognized nationally and internationally. Replication of the model in every suitable area would bring a positive response. (orig.)

  4. Crustal structure of the western Yamato Basin, Japan Sea, revealed from seismic survey

    Science.gov (United States)

    No, T.; Sato, T.; Kodaira, S.; Miura, S.; Ishiyama, T.; Sato, H.

    2015-12-01

    The Yamato Basin is the second largest basin of the Japan Sea. This basin is important to clarify its formation process. Some studies of crustal structure had been carried out in the Yamato Basin (e.g. Ludwig et al., 1975; Katao, 1988; Hirata et al., 1989; Sato et al., 2006). However, the relationship between formation process and crustal structure is not very clear, because the amount of seismic exploration data is very limited. In addition, since there is ODP Leg 127 site 797 (Tamaki et al., 1990) directly beneath our seismic survey line, we contributed to the study on the formation of the Yamato Basin by examining the relation between the ODP results and our results. During July-August 2014, we conducted a multi-channel seismic (MCS) survey and ocean bottom seismometer (OBS) survey to study the crustal structure of the western Yamato Basin. We present an outline of the data acquisition and results of the data processing and preliminary interpretations from this study. As a result of our study, the crust, which is about 12 km thick, is thicker than standard oceanic crust (e.g., Spudich and Orcutt, 1980; White et al., 1992) revealed from P-wave velocity structure by OBS survey. A clear reflector estimated to be the Moho can be identified by MCS profiles. The characteristics of the sedimentary layer are common within the survey area. For example, a strong coherent reflector that is estimated to be an opal-A/opal-CT BSR (bottom simulating reflector) (Kuramoto et al., 1992) was confirmed in the sediment of all survey lines. On the other hand, a coherent reflector in the crust was confirmed in some lines. It is identified as this reflector corresponding with the deformation structure in the sediment and basement.

  5. Biomes of western North America at 18,000, 6000 and 0 14C yr BP reconstructed from pollen and packrat midden data

    Science.gov (United States)

    Thompson, R.S.; Anderson, K.H.

    2000-01-01

    A new compilation of pollen and packrat midden data from western North America provides a refined reconstruction of the composition and distribution of biomes in western North America for today and for 6000 and 18,000 radiocarbon years before present (14C yr BP). Modern biomes in western North America are adequately portrayed by pollen assemblages from lakes and bogs. Forest biomes in western North America share many taxa in their pollen spectra and it can be difficult to discriminate among these biomes. Plant macrofossils from packrat middens provide reliable identification of modern biomes from arid and semiarid regions, and this may also be true in similar environments in other parts of the world. However, a weighting factor for trees and shrubs must be used to reliably reconstruct modern biomes from plant macrofossils. A new biome, open conifer woodland, which includes eurythermic conifers and steppe plants, was defined to categorize much of the current and past vegetation of the semiarid interior of western North America. At 6000 14C yr BP, the forest biomes of the coastal Pacific North-west and the desert biomes of the South-west were in near-modern positions. Biomes in the interior Pacific North-west differed from those of today in that taiga prevailed in modern cool/cold mixed forests. Steppe was present in areas occupied today by open conifer woodland in the northern Great Basin, while in the central and southern Rocky Mountains forests grew where steppe grows today. During the mid-Holocene, cool conifer forests were expanded in the Rocky Mountains (relative to today) but contracted in the Sierra Nevada. These differences from the forests of today imply different climatic histories in these two regions between 6000 14C yr BP and today. At 18,000 14C yr BP, deserts were absent from the South-west and the coverage of open conifer woodland was greatly expanded relative to today. Steppe and tundra were present in much of the region now covered by forests in

  6. Remote Sensing Observations of Snow and Soil Moisture for Snowmelt Flood Predictions in the Red River of the North Basin

    Science.gov (United States)

    Tuttle, S. E.; Jacobs, J. M.; Vuyovich, C.; Cho, E.; Restrepo, P. J.; Jia, X.; Cosh, M. H.; Deweese, M. M.; Connelly, B.; Buan, S.

    2015-12-01

    The northward-flowing Red River of the North Basin (RRB), located in eastern North Dakota and western Minnesota, is vulnerable to frequent floods due to its flat terrain and low permeability soil. A vast majority of floods in the basin occur during the snowmelt season, when the winter snowpack thaws and spring rains fall onto saturated soils. This causes the Red River to spill over shallow banks and across the floodplain. The region has sparse in situ observations of snow and soil moisture, making flood prediction in the RRB difficult. Remote sensing data can help to capture magnitude, timing, and spatial distribution of watershed scale snow, soil moisture, and snowmelt parameters in the RRB, which will allow for better characterization of the watershed's hydrologic state. This research examines snow water equivalent (SWE; from the AMSR-E, AMSR2, and SSM/I satellite instruments), soil moisture (from AMSR-E, SMOS, and SMAP), and snow covered area (SCA; from MODIS), along with modeled SWE and snow depth from NOAA's National Operational Hydrologic Remote Sensing Center (NOHRSC) SNOw Data Assimilation System (SNODAS). These data are compared with observations from local and federal snow surveys, NOHRSC Airborne Gamma Radiation Snow Survey Program flights, NOAA National Climate Data Center (NCDC) cooperative network sites, Natural Resource Conservation Service (NRCS) Soil Climate Analysis Network (SCAN) sites, and the North Central River Forecast Center's (NCRFC) model states, in order to determine data quality as well as strengths and weaknesses of satellite observations for RRB flood forecasting. Future analyses will include evaluation of freeze/thaw state information from the Soil Moisture Active-Passive (SMAP) satellite, and explore the potential for flood forecasting improvement by updating state variables of the NOAA National Weather Service (NWS) operational forecasting models with remotely sensed fields.

  7. Deformation History of the Haymana Basin: Structural Records of Closure-Collision and Subsequent Convergence (Indentation) Events at the North-Central Neotethys (Central Anatolia, Turkey)

    Science.gov (United States)

    Gülyüz, Erhan; Özkaptan, Murat; Kaymakcı, Nuretdin

    2016-04-01

    Gondwana- (Tauride Platfrom and Kırşehir Block) and Eurasia (Pontides) - derived continental blocks bound the Haymana basin, in the south and north, respectively. Boundaries between these blocks are signed by İzmir-Ankara-Erzincan and debatable Intra-Tauride Suture zones which are straddled by the Haymana Basin in the region. In this regard, deformation recorded in the upper Cretaceous to middle Eocene deposits of the basin is mainly controlled by the relative movements of these blocks. Therefore, understanding the structural evolution of the Haymana Basin in a spatio-temporal concept is crucial to shed some light on some debatable issues such as ; (1) timing of late stage subduction histories of various branches of Neotethys and subsequent collision events, (2) effects of post-collisional tectonic activity in the Haymana region. Fault kinematic analyses (based on 623 fault-slip data from 73 stations) indicate that the basin was subjected to initially N-S to NNE-SSW extension until middle Paleocene and then N-S- to NNE-SSW- directed continuous compression and coeval E-W to ESE-WNW extension up to middle Miocene. These different deformation phases correspond to the fore-arc (closure) and foreland (collision and further convergence) stages of the basin. Additionally, fold analyses (based on 1017 bedding attitudes) and structural mapping studies show that development of folds and major faults are coeval and they can be explained by principle stress orientations of the second deformation phase. The Haymana basin is, based on the trends of E-W- and WNW-ESE- directed structures at the south-eastern and the north-western parts of the basin, respectively, divided into two structural segments. The balanced cross-sections also indicate ~4% and ~25% shortening at the north-western and south-eastern segments, respectively. The differences in amounts of shortenings are explained by reduce in effectiveness zone of basin-bounding thrust faults towards west. On the other hand

  8. Sources and summaries of water-quality information for the Rapid Creek basin, western South Dakota

    Science.gov (United States)

    Zogorski, John S.; Zogorski, E.M.; McKallip, T.E.

    1990-01-01

    This report provides a compilation of water quality information for the Rapid Creek basin in western South Dakota. Two types of information are included: First, past and current water quality monitoring data collected by the South Dakota Department of Water and Natural Resources, U.S. Forest Service, U.S. Geological Survey, and others are described. Second, a summary is included for all past water quality reports, publications, and theses that could be located during this study. A total of 62 documents were abstracted and included journal articles, abstracts, Federal agency reports and publications, university and State agency reports, local agency reports, and graduate theses. The report should be valuable to water resources managers, regulators, and others contemplating water quality research, monitoring, and regulatory programs in the Rapid Creek basin. (USGS)

  9. Agribusiness geothermal energy utilization potential of Klamath and Western Snake River Basins, Oregon. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1978-03-01

    Resource assessment and methods of direct utilization for existing and prospective food processing plants have been determined in two geothermal resource areas in Oregon. Ore-Ida Foods, Inc. and Amalgamated Sugar Company in the Snake River Basin; Western Polymer Corporation (potato starch extraction) and three prospective industries--vegetable dehydration, alfalfa drying and greenhouses--in the Klamath Basin have been analyzed for direct utilization of geothermal fluids. Existing geologic knowledge has been integrated to indicate locations, depth, quality, and estimated productivity of the geothermal reservoirs. Energy-economic needs and balances, along with cost and energy savings associated with field development, delivery systems, in-plant applications and fluid disposal have been calculated for interested industrial representatives.

  10. [Proof of the indigenous nature of Populus alba L. in the western Mediterranean Basin].

    Science.gov (United States)

    Roiron, Paul; Ali, Adam A; Guendon, Jean-Louis; Carcaillet, Christopher; Terral, Jean-Frédéric

    2004-02-01

    Around the western Mediterranean Basin, the ecological status of Populus alba, whether indigenous or introduced, is controversial. This note presents new palaeobotanical data based on analyses of leaf imprints from a travertine formation located in southern France. This travertine presents two levels with Populus alba imprints. The oldest level is dated back by 14C to the Early Holocene, i.e., 8890 +/- 70 BP. This demonstrates that Populus alba is an autochthonous species of the southern-France vegetation, removing speculations reporting that its distribution area was greatly influenced by Roman civilization. Finally, we discuss this new data in regard to other Pleistocene and Holocene deposits circum the Mediterranean Basin and in Europe, where this species was identified. PMID:15060983

  11. Plutonium distribution and remobilization in sediments of the Rhone River mouth (North-Western Mediterranean)

    International Nuclear Information System (INIS)

    discharged over the 40 past years by the Marcoule reprocessing plant, are currently trapped in the sediments off the Rhone River mouth. Plutonium remobilization is potentially an important process but dispersion of contaminated sediments appeared to be limited in space. These results suggest a low exportation of particulate matter introduced by the Rhone River towards the continental shelf of the Gulf of Lions and the North-Western Mediterranean basin. (author)

  12. Late Ordovician-Early Silurian chitinozoans from north-eastern and western Illinois, USA

    Science.gov (United States)

    Butcher, A.; Mikulic, Donald G.; Kluessendorf, Joanne

    2010-01-01

    Samples of uppermost Ordovician and Silurian strata from two cores from north-eastern and western Illinois were processed for chitinozoans. Due to apparent sea-floor oxidation or palaeoenvironmental constraints, very few samples yielded specimens, but those that did allow tentative correlation with established biostratigraphical zonations for the Chitinozoa. Samples from the Wilhelmi Formation of core DH76-21 in north-eastern Illinois yielded Spinachitina fragilis, a typically earliest Silurian taxon. A sample from the Maquoketa Group strata of core Principia #4, western Illinois, yielded a monospecific assemblage of Conochitina elegans, which is suggestive of a late Ordovician age. Higher in this core, a sample from the upper strata of the Bowling Green Dolomite yielded an assemblage indicating a late Rhuddanian to Aeronian age, including Angochitina hansonica, previously only described from strata in Nevada, and one new species, Fungochitina illinoisensis. ?? 2009 Elsevier B.V. All rights reserved.

  13. Interannual variability and future projection of summertime ocean wave heights in the western North Pacific

    Directory of Open Access Journals (Sweden)

    W. Sasaki

    2006-10-01

    Full Text Available A 70-yr (from 1985–1995 to 2055–2065 change of decadal mean summertime extreme significant wave heights (SWH in the western North Pacific under CO2-induced global warming condition is projected. For this purpose, possible atmospheric fields under future global warming are derived from 10-yr time-slice experiments using a T106 AGCM. The future changes of SWH are assessed by an empirical approach, where possible changes of SWH are estimated using a linear regression model which shows an empirical relationship between SWH anomalies and an eastward shift of the monsoon trough. It is projected that SWH increases by up to ~0.4 m over a wide area of the western North Pacific.

  14. Invertase and urease activities in the reclamated land of the western Donets basin

    Directory of Open Access Journals (Sweden)

    O. M. Vasilyuk

    2009-09-01

    Full Text Available The research data on activities of invertase (as one of the most important enzymes for soil biological activity, humus content and soil fertility and urease (as an enzyme of nitrogen metabolism, which transforms the inorganic nitrogen compounds into the organic ones in soils of artificial afforestations of Robinia pseudoacacia L., Betula pendula Rosh., Quercus robur L. and Acer platanoides L. at the reclamated lands of the Western Donets Basin are presented. The seasonal dynamics of soil activity subject to the type of biogeocenosis is shown.

  15. Avian mercury exposure and toxicological risk across western North America: A synthesis

    Science.gov (United States)

    Ackerman, Josh; Eagles-Smith, Collin A.; Herzog, Mark; Hartman, Christopher; Peterson, Sarah; Evers, David C.; Jackson, Allyson K.; Elliott, John E.; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that

  16. Participatory integrated watershed management in the north-western highlands of Rwanda

    OpenAIRE

    Kagabo, M.D.

    2013-01-01

    This thesis is the result of assessments on the extent of existing resource use and management practices using a Participatory Integrated Watershed Management (PIWM) as a viable approach to promote best soil water conservation (SWC) measures towards more sustainable land use. The study was conducted in two contrasting agro-ecological zones of the north-western highlands of Rwanda, namely; Gataraga and Rwerere in the framework of “Agasozi ndatwa”  referred to as PIWM. "Ag...

  17. Survey of thermophilic Campylobacter species in cats and dogs in north-western Nigeria

    OpenAIRE

    Adewale Kolawale; Junaidu U. Abdulkadir; Abdullahi A. Magaji; Mohammed D. Salihu

    2010-01-01

    This study was conducted in north-western Nigeria to investigate the role of cats and dogs as potential reservoirs of thermophilic Campylobacter species. Faecal samples were analysed from 104 cats and 141 dogs between March 2007 and March 2009. The samples were collected from animals in households, those presented to veterinary premises and feline colonies. Campylobacter spp. were isolated from 39 (27.7%) and 19 (18.3%) dogs and cats, respectively. There was no significant difference in isola...

  18. Disruption of ecosystem processes in western North America by invasive species

    OpenAIRE

    Dukes, Jeffrey S.; Mooney, Harold A.

    2004-01-01

    Many ecosystems of western North America have been dramatically changed by non-native species. Here, we review ecological impacts of 56 plant, animal, fungus, and protist species that were brought to this region by humans. We discuss characteristics of invasive species that can lead to major ecosystem impacts, and explore how invasive species alter many different attributes of ecosystems. Specifically, we include examples of invasive species that affect geomorphology, fire regimes, hydrology,...

  19. Modeling Employment, Housing, and Population in Western North Dakota: The Case of Dickinson

    OpenAIRE

    Bangsund, Dean A.; Hodur, Nancy M.; Rathge, Richard W.; Olson, Karen

    2012-01-01

    Communities in western North Dakota are struggling to manage the unprecedented growth in employment associated with the current oil boom. The city of Dickinson is undergoing a comprehensive plan to develop policies, strategies, and solutions for providing infrastructure, transportation, housing, and public services as a result of the new conditions brought on by oil field development. This study was designed to provide input into the city’s comprehensive planning effort. Employment projection...

  20. Tempo-spatial patterns of bacterial community composition in the western North Pacific Ocean

    OpenAIRE

    Kataoka, Takafumi; Hodoki, Yoshikuni; Suzuki, Koji; Saito, Hiroaki; Higashi, Seigo

    2009-01-01

    In the western North Pacific, where subarctic Oyashio waters encounter subtropical Kuroshio waters, phylotype composition of heterotrophic bacteria was estimated by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified bacterial 16S ribosomal DNA. Total bacterial abundance was also measured by flow cytometry. The study area was divided into four water masses: coastal, Oyashio, Kuroshio, and the Kuroshio-Oyashio transition. Abundances of heterotrophic bacteria in the Oyashio, Kuroshi...

  1. Analysis on Variations of the Temperature and Precipitation in North Slope Area of the Western Tianshan in Recent 50 Years

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective]The research aimed to analyze variation characteristics of the temperature and precipitation in north slope area of the Western Tianshan in recent 50 years.[Method] According to temperature and rainfall data from 1961 to 2010 at three meteorological stations in north slope area of the Western Tianshan,climate change in the zone in recent 50 years was analyzed by using linear trend analysis method and 5-year sliding average method.[Result] The temperature in north slope area of the Western Tiansha...

  2. First Detection of Bat White-Nose Syndrome in Western North America.

    Science.gov (United States)

    Lorch, Jeffrey M; Palmer, Jonathan M; Lindner, Daniel L; Ballmann, Anne E; George, Kyle G; Griffin, Kathryn; Knowles, Susan; Huckabee, John R; Haman, Katherine H; Anderson, Christopher D; Becker, Penny A; Buchanan, Joseph B; Foster, Jeffrey T; Blehert, David S

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused by Pseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction of P. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation. IMPORTANCE White-nose syndrome (WNS) represents one of the most consequential wildlife diseases of modern times. Since it was first documented in New York in 2006, the disease has killed millions of bats and threatens several formerly abundant species with extirpation or extinction. The spread of WNS in eastern North America has been relatively gradual, inducing optimism that disease mitigation strategies could be established in time to conserve bats susceptible

  3. The Moisture Structure of ISO in Western North Pacific Revealed by AIRS

    Institute of Scientific and Technical Information of China (English)

    TAO Li; FU Xiouhua; WANG Bin

    2009-01-01

    Using the humidity profiles from the Atmospheric Infrared Sounder (AIRS) dataset, rainfall from the Tropical Rainfall Measuring Mission (TRMM) Global Precipitation Index (GPI), and surface winds from QuickSCAT (QSCAT) as well as SST from the Advanced Microwave Scanning Radiometer for NASA's Earth Observing System (AMSR_E), we analyzed the structure of summer intraseasonal oscillation (ISO) over the western North Pacific region in 2003-2004. We find that the signal of 20-90-day oscillations in the western North Pacific originates from the equatorial Indian Ocean, and propagates eastward to Philippine Sea and then moves northwestward to South China. The AIRS humidity data reveal that the boundary-layer moisture leads the mid-troposphere moisture during the ISO propagation. The positive SST anomaly may play an important role to moistening the boundary-layer, which preconditions the ISO propagation. Therefore, the intraseasonal SST anomaly could positively feed back to the atmosphere through moistening the boundary-layer, destabilizing the troposphere, and contributing to the northwestward propagation of the ISO in western North Pacific. On the other hand, the salient feature that the boundary-layer moisture anomaly leads mid-troposphere moisture does not exist in ECMWF/TOGA analysis.

  4. The intertropical convergence zone modulates intense hurricane strikes on the western North Atlantic margin.

    Science.gov (United States)

    van Hengstum, Peter J; Donnelly, Jeffrey P; Fall, Patricia L; Toomey, Michael R; Albury, Nancy A; Kakuk, Brian

    2016-01-01

    Most Atlantic hurricanes form in the Main Development Region between 9°N to 20°N along the northern edge of the Intertropical Convergence Zone (ITCZ). Previous research has suggested that meridional shifts in the ITCZ position on geologic timescales can modulate hurricane activity, but continuous and long-term storm records are needed from multiple sites to assess this hypothesis. Here we present a 3000 year record of intense hurricane strikes in the northern Bahamas (Abaco Island) based on overwash deposits in a coastal sinkhole, which indicates that the ITCZ has likely helped modulate intense hurricane strikes on the western North Atlantic margin on millennial to centennial-scales. The new reconstruction closely matches a previous reconstruction from Puerto Rico, and documents a period of elevated intense hurricane activity on the western North Atlantic margin from 2500 to 1000 years ago when paleo precipitation proxies suggest that the ITCZ occupied a more northern position. Considering that anthropogenic warming is predicted to be focused in the northern hemisphere in the coming century, these results provide a prehistoric analog that an attendant northern ITCZ shift in the future may again return the western North Atlantic margin to an active hurricane interval. PMID:26906670

  5. Interdecadal shift in the western North Pacific Summer SST anomaly in the late 1980s

    Institute of Scientific and Technical Information of China (English)

    WU BingYi; ZHANG RenHe

    2007-01-01

    An interdecadal shift in summer (June-August) sea surface temperature (SST) variations during the period of 1968―2002 was identified in the late 1980s, which is characterized by a phase alternating from negative to positive phases of the leading mode of the empirical orthogonal function (EOF) analysis of the summer monthly mean SST in the Pacific domain 100°―180°E and 0°―40°N, accounting for 30.5% of the total variance. During the period of 1968―1987, the leading mode with a mean negative phase state (mean standard deviation = -0.586) controlled SST variability in the western North Pacific. Correspondingly, negative SST anomalies occupied the western North Pacific south of Japan and Chinese marginal seas. During the period of 1988―2002, the leading mode shifted to its strong positive polarity (mean standard deviation = 0.781), thus positive SST anomalies appeared in the western North Pacific. Accompanied by the interdecadal shift in summer mean SST, summer mean rainfall increased in southern and southeastern China during the late period, particularly in southeastern China where increase in summer mean rainfall exceeded 40 mm, at the 0.05 significance level.

  6. Lithosphere, crust and basement ridges across Ganga and Indus basins and seismicity along the Himalayan front, India and Western Fold Belt, Pakistan

    Science.gov (United States)

    Ravi Kumar, M.; Mishra, D. C.; Singh, B.

    2013-10-01

    Spectral analysis of the digital data of the Bouguer anomaly of North India including Ganga basin suggest a four layer model with approximate depths of 140, 38, 16 and 7 km. They apparently represent lithosphere-asthenosphere boundary (LAB), Moho, lower crust, and maximum depth to the basement in foredeeps, respectively. The Airy's root model of Moho from the topographic data and modeling of Bouguer anomaly constrained from the available seismic information suggest changes in the lithospheric and crustal thicknesses from ˜126-134 and ˜32-35 km under the Central Ganga basin to ˜132 and ˜38 km towards the south and 163 and ˜40 km towards the north, respectively. It has clearly brought out the lithospheric flexure and related crustal bulge under the Ganga basin due to the Himalaya. Airy's root model and modeling along a profile (SE-NW) across the Indus basin and the Western Fold Belt (WFB), (Sibi Syntaxis, Pakistan) also suggest similar crustal bulge related to lithospheric flexure due to the WFB with crustal thickness of 33 km in the central part and 38 and 56 km towards the SE and the NW, respectively. It has also shown the high density lower crust and Bela ophiolite along the Chamman fault. The two flexures interact along the Western Syntaxis and Hazara seismic zone where several large/great earthquakes including 2005 Kashmir earthquake was reported. The residual Bouguer anomaly maps of the Indus and the Ganga basins have delineated several basement ridges whose interaction with the Himalaya and the WFB, respectively have caused seismic activity including some large/great earthquakes. Some significant ridges across the Indus basin are (i) Delhi-Lahore-Sargodha, (ii) Jaisalmer-Sibi Syntaxis which is highly seismogenic. and (iii) Kachchh-Karachi arc-Kirthar thrust leading to Sibi Syntaxis. Most of the basement ridges of the Ganga basin are oriented NE-SW that are as follows (i) Jaisalmer-Ganganagar and Jodhpur-Chandigarh ridges across the Ganga basin intersect

  7. Characteristics of Heavy Minerals in Tertiary System of Western Qaidamu Basin

    Institute of Scientific and Technical Information of China (English)

    PENG De-hua; WANG Chao-yong

    2005-01-01

    According to tectonic position and mineral inclusions, supply resource in western Qaidamu basin is divided into the front of Aerjinshan mountain and the front of Qimantageshan mountain. The former is mainly composed of zircon, garnet inclusions, indicating that its mother rocks are mainly metamorphic rocks. Gas and zircon, iron ore, carbon grain inclusions is common in the front of Qimantage mountain, indicating that its mother rock are mainly magmatite and mixed metamorphic rocks. The supply resource is abundant and tectonic movement is active in the joint of the two mountains. The western Qaidamu basin is further divided into 6 heavy mineral sub-regions according to their features of association and stable coefficient of heavy mineral. They are approximately corresponding to their sedimentary environment. Of the 6 sub-regions, the unstable region is corresponding to fluvial fan, middle stable region is corresponding to river-alluvial plain-delta, stable region is corresponding to river-alluvial plain -delta-offshore. The fragment transported distance is presumed based on stable coefficient. In vertical, stable coefficient of heavy mineral becomes small from Xiaganchai formation to Xiayoushashan formation, indicating that the supply resource became nearer and nearer.

  8. Seismic Structural Setting of Western Farallon Basin, Southern Gulf of California, Mexico.

    Science.gov (United States)

    Pinero-Lajas, D.; Gonzalez-Fernandez, A.; Lopez-Martinez, M.; Lonsdale, P.

    2007-05-01

    Data from a number of high resolution 2D multichannel seismic (MCS) lines were used to investigate the structure and stratigraphy of the western Farallon basin in the southern Gulf of California. A Generator-Injector air gun provided a clean seismic source shooting each 12 s at a velocity of 6 kts. Each signal was recorded during 6- 8 s, at a sampling interval of 1 ms, by a 600 m long digital streamer with 48 channels and a spacing of 12.5 m. The MCS system was installed aboard CICESE's (Centro de Investigacion Cientifica y de Educacion Superior de Ensenada) 28 m research vessel Francisco de Ulloa. MCS data were conventionally processed, to obtain post- stack time-migrated seismic sections. The MCS seismic sections show a very detailed image of the sub-bottom structure up to 2-3 s two-way travel time (aprox. 2 km). We present detailed images of faulting based on the high resolution and quality of these data. Our results show distributed faulting with many active and inactive faults. Our study also constrains the depth to basement near the southern Baja California eastern coast. The acoustic basement appears as a continuous feature in the western part of the study area and can be correlated with some granite outcrops located in the southern Gulf of California islands. To the East, near the center of the Farallon basin, the acoustic basement changes, it is more discontinuous, and the seismic sections show a number of diffracted waves.

  9. ESTIMATED DATE OF COMPLETION OF THE PLANNED MOTORWAY SEGMENTS IN THE CENTRAL, NORTH-WESTERN AND WESTERN REGIONS OF ROMANIA

    Directory of Open Access Journals (Sweden)

    CSUTAK ISTVAN

    2013-08-01

    Full Text Available Romania’s highways are standing ahead of considerably high investments. In the last few decades thetransport infrastructure has been pushed into the background due to lack of financial support. The 21st Centuryhas brought important breakthroughs in the building of highways. In the report on global risks in 2013published by WEF (World Economic Forum the "The prolonged neglect of infrastructure" is being consideredsuch a risk. Our study focuses on the construction works that have been carried out in the Central, North-Western and Western regions of Romania. The highways of the above mentioned regions will be analysed basedon three main points of focus: highways that have already been built, highways currently under construction andhighways that are planned to be built. The aim is to present and compare the 3 regions’ highway infrastructure,determination of an approximate end date for the highways that are currently under construction. It has beenconcluded, that until 2013 the construction work on segments funded by the EU progressed much faster, than theones funded by the government. The results of the study refer to how soon could the construction works reach anend on segments currently in progress.

  10. Ground-water availability from surficial aquifers in the Red River of the North Basin, Minnesota

    Science.gov (United States)

    Reppe, Thomas H.C.

    2005-01-01

    Population growth and commercial and industrial development in the Red River of the North Basin in Minnesota, North Dakota, and South Dakota have prompted the Bureau of Reclamation, U.S. Department of the Interior, to evaluate sources of water to sustain this growth. Nine surficial-glacial (surficial) aquifers (Buffalo, Middle River, Two Rivers, Beach Ridges, Pelican River, Otter Tail, Wadena, Pineland Sands, and Bemidji-Bagley) within the Minnesota part of the basin were identified and evaluated for their ground-water resources. Information was compiled and summarized from published studies to evaluate the availability of ground water. Published information reviewed for each of the aquifers included location and extent, physical characteristics, hydraulic properties, ground-water and surface-water interactions, estimates of water budgets (sources of recharge and discharge) and aquifer storage, theoretical well yields and actual ground-water pumping data, recent (2003) ground-water use data, and baseline ground-water-quality data.

  11. Approximate western limit of glaciation within the Standing Rock Indian Reservation, Sioux County, North Dakota, and Corson County, South Dakota

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This coverage contains information about the western limit of glaciation within the Standing Rock Indian Reservation, Sioux County, North Dakota, and Corson County,...

  12. Top of Head Scarp and Internal Scarps for Landslide Deposits in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent head scarps, flank scarps, and minor internal scarps (linear) associated with landslide deposits in the Little North Santiam River Basin,...

  13. Tropical Cyclone Exposure for U.S. waters within the North Atlantic Ocean basin, 1900-2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent modeled, historical exposure of U.S. offshore and coastal waters to tropical cyclone activity within the North Atlantic Ocean basin. BOEM Outer...

  14. Deep formation waters of Western Europe, Russia and North America characterised by sodium, calcium, magnesium and chloride concentrations

    Science.gov (United States)

    Bozau, Elke; Hemme, Christina; Sattler, Carl-Diedrich; van Berk, Wolfgang

    2015-04-01

    Deep formation water can be classified according to depth, temperature, and salinity (e.g., Graf et al. 1966, Kharaka & Hanor 2007). Most of the deep formation waters contain dissolved solids in excess of sea water. The hydrogeochemical development of formation water has been discussed for a long time. It is widely accepted that deep aquifers are influenced by the meteoric cycle and geochemical processes within the crust (e.g., Hebig et al. 2012). Similar hydrogeochemical signatures are found in deep formation waters of all continents and can be explained by general geochemical processes within the deep reservoirs (e.g., Land 1995). Therefore, data of deep formation waters from Western Europe, Russia, and North America are collected and classified by the major water components. The data are used to identify important hydrogeochemical processes (e.g., halite dissolution and albitisation) leading to different compositions of formation water. Two significant water types are identified: Na-Cl water and Na-Ca-Cl water. Based on the collected hydrogeochemical data, development trends are stated for the formation waters, and albitisation is favoured as the main process for calcium enrichment. Furthermore, differences of formation water according to stratigraphical units are shown for deep reservoirs of the North German Basin and the North Sea. References: Graf, D.L., 1982. Chemical osmosis, reverse chemical osmosis, and the origin of subsurface brines. Geochimica Cosmochimica Acta 46, 1431-1448. Hebig, K.H., Ito, N., Scheytt, T., Marui, A., 2012. Review: Deep groundwater research with focus on Germany. Hydrogeology Journal 20, 227-243. Kharaka, Y.K., Hanor, J.S., 2007. Deep fluids in continents: I. Sedimentary Basins. Treatise on Geochemistry 5, 1-48. Land, L.S., 1995. The role of saline formation water in the crustal cycling. Aquatic Geochemistry 1, 137-145. Acknowledgements: The presented data are results of the collaborative research program "gebo" (Geothermal energy

  15. Reexamination of the geological structure of the North German Basin in Lower Saxony

    Science.gov (United States)

    Rienäcker, Julia; Sattler, Sabine

    2016-04-01

    The North German Basin (NGB), as part of the Southern Permian Basin in Europe, extends from the North Sea, across Denmark, the Netherlands through Northern Germany, to Poland. It contains sediments from the Lower Permian to the Quaternary, and experienced a minimum subsidence of 2000 m from the Permian to the Mesozoic. This was followed by uplift during Late Cretaceous-Early Cenozoic inversion. The hundreds of meters thick and mobile Zechstein salt of Late Permian was remobilized in several phases to form complex salt structures. The salt moved laterally and vertically thus creating salt pillows and tall asymmetrical salt diapirs, some of which broke through the overburden until they were exposed at the paleo-surface. Salt structures influenced both the sedimentation and structural style throughout the NGB. Within the joint project TUNB (Deeper Underground North German Basin), 2-D/3-D seismic datasets, borehole data, structural maps and the existing 3-D geological model of Lower Saxony, will be used to create a new, detailed, geological 3-D model of the Lower Saxony part of the NGB. This allows new insights into the interplay between salt tectonics, sedimentation and tectonic movement, and in particular may help to resolve issues regarding the influence of the Zechstein salt on the sediment distribution. We show the different structural styles of important reservoir formations for, e.g., hydrocarbons, geothermal energy and gas storage, such as the Middle Buntsandstein, Rhaetkeuper, Middle Jurassic, and Lower Cretaceous, especially related to salt structures.

  16. Reservoir heterogeneity in Carter Sandstone, North Blowhorn Creek oil unit and vicinity, Black Warrior Basin, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, R.L.; Pashin, J.C.

    1992-05-01

    This report presents accomplishments made in completing Task 3 of this project which involves development of criteria for recognizing reservoir heterogeneity in the Black Warrior basin. The report focuses on characterization of the Upper Mississippian Carter sandstone reservoir in North Blowhorn Creek and adjacent oil units in Lamar County, Alabama. This oil unit has produced more than 60 percent of total oil extracted from the Black Warrior basin of Alabama. The Carter sandstone in North Blowhorn Creek oil unit is typical of the most productive Carter oil reservoirs in the Black Warrior basin of Alabama. The first part of the report synthesizes data derived from geophysical well logs and cores from North Blowhorn Creek oil unit to develop a depositional model for the Carter sandstone reservoir. The second part of the report describes the detrital and diagenetic character of Carter sandstone utilizing data from petrographic and scanning electron microscopes and the electron microprobe. The third part synthesizes porosity and pore-throat-size-distribution data determined by high-pressure mercury porosimetry and commercial core analyses with results of the sedimentologic and petrographic studies. The final section of the report discusses reservoir heterogeneity within the context of the five-fold classification of Moore and Kugler (1990).

  17. Assessment of the sardine (Sardina pilchardus Walbaum, 1792 fishery in the eastern Mediterranean basin (North Aegean Sea

    Directory of Open Access Journals (Sweden)

    K. ANTONAKAKIS

    2012-12-01

    Full Text Available The aim of this study was to describe the biometric characteristics of the European sardine (Sardina pilchardus catches and assess the current status of sardine stock in North Aegean Sea based on population characteristics and abundance trends. The stock was dominated by age groups 1 and 2, not exceeding age group 4. The sardine stock in this area was assessed through an Integrated Catch-at-Age model which implements a separable Virtual Population Analysis on catch at age data with weighted tuning indices. Sardine landings data derived from the commercial purse seine fishery over the period 2000-2008 were combined with the age structure of the stock as resulted from fisheries independent acoustic surveys. Sensitivity analysis of the impact of natural mortality values on stock assessment results was applied. Additionally forecast of the sardine population parameters and catches under different exploitation scenarios was implemented in a medium term basis. Results indicated that the North Aegean Sea sardine stock is considered fully exploited with the fishery operating close but over the empirical exploitation level for sustainability. Finally, the status of the sardine stock in N. Aegean Sea is discussed in relation to the sardine stocks from the western and the central Mediterranean basin.

  18. Origin of fine carbonaceous particulate matter in the Western Mediterranean Basin: fossil versus modern sources

    Science.gov (United States)

    Cruz Minguillón, María.; Perron, Nolwenn; Querol, Xavier; Szidat, Sönke; Fahrni, Simon; Wacker, Lukas; Reche, Cristina; Cusack, Michael; Baltensperger, Urs; Prévôt, André S. H.

    2010-05-01

    The present work was carried out in the frame of the international field campaign DAURE (Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in the western Mediterranean). The objective of this campaign is to study the aerosol pollution episodes occurring at regional scale during winter and summer in the Western Mediterranean Basin. As part of this campaign, this work focuses on identifying the origin of fine carbonaceous aerosols. To this end, fine particulate matter (PM1) samples were collected during two different seasons (February-March and July 2009) at two sites: an urban site (Barcelona, NE Spain) and a rural European Supersite for Atmospheric Aerosol Research (Montseny, NE Spain). Subsequently, 14C analyses were carried out on these samples, both in the elemental carbon (EC) fraction and the organic carbon (OC) fraction, in order to distinguish between modern carbonaceous sources (biogenic emissions and biomass burning emissions) and fossil carbonaceous sources (mainly road traffic). Preliminary results from the winter period show that 40% of the OC at Barcelona has a fossil origin whereas at Montseny this percentage is 30%. These values can be considered as unexpected given the nature of the sites. Nevertheless, the absolute concentrations of fossil OC at Barcelona and Montseny differ by a factor of 2 (the first being higher), since the total OC at Montseny is lower than at Barcelona. Further evaluation of results and comparison with other measurements carried out during the campaign are required to better evaluate the origin of the fine carbonaceous matter in the Western Mediterranean Basin. Acknowledgements: Spanish Ministry of Education and Science, for a Postdoctoral Grant awarded to M.C. Minguillón in the frame of Programa Nacional de Movilidad de Recursos Humanos del Plan nacional de I-D+I 2008-2011. Spanish Ministry of Education and Science, for the Acción Complementaria DAURE CGL2007-30502-E/CLI.

  19. Benthic macrofaunal production for a typical shelf-slope-basin region in the western Arctic Ocean

    Science.gov (United States)

    Lin, Heshan; Wang, Jianjun; Liu, Kun; He, Xuebao; Lin, Junhui; Huang, Yaqin; Zhang, Shuyi; Mou, Jianfeng; Zheng, Chengxing; Wang, Yu

    2016-02-01

    Secondary production by macrofaunal communities in the western Arctic Ocean were quantified during the 4th and 5th Chinese Arctic Scientific Expeditions. The total production and P/B ratio for each sector ranged from 3.8 (±7.9) to 615.6 (±635.5) kJ m-2 yr-1 and 0.5 (± 0.2) to 0.7 (± 0.2) yr-1, respectively. The shallow shelves in the western Arctic Ocean exhibited particularly high production (178.7-615.6 kJ m-2 yr-1), particularly in the two "hotspots" - the southern and northeastern (around Barrow Canyon) Chukchi Sea. Benthic macrofaunal production decreased sharply with depth and latitude along a shelf-slope-basin transect, with values of 17.0-269.8 kJ m-2 yr-1 in slope regions and 3.8-10.1 kJ m-2 yr-1 in basins. Redundancy analysis indicated that hydrological characteristics (depth, bottom temperature and salinity) and granulometric parameters (mean particle size, % sand and % clay) show significant positive/negative correlations with total production. These correlations revealed that the dominant factors influencing benthic production are the habitat type and food supply from the overlying water column. In the Arctic, the extreme environmental conditions and low temperature constrain macrofaunal metabolic processes, such that food and energy are primarily used to increase body mass rather than for reproduction. Hence, energy turnover is relatively low at high latitudes. These data further our understanding of benthic production processes and ecosystem dynamics in the context of rapid climate change in the western Arctic Ocean.

  20. Detection of North American eastern and western equine encephalitis viruses by nucleic acid amplification assays.

    Science.gov (United States)

    Lambert, Amy J; Martin, Denise A; Lanciotti, Robert S

    2003-01-01

    We have developed nucleic acid sequence-based amplification (NASBA), standard reverse transcription PCR (RT-PCR), and TaqMan nucleic acid amplification assays for the rapid detection of North American eastern equine encephalitis (EEE) and western equine encephalitis (WEE) viral RNAs from samples collected in the field and clinical samples. The sensitivities of these assays have been compared to that of virus isolation. While all three types of nucleic acid amplification assays provide rapid detection of viral RNAs comparable to the isolation of viruses in Vero cells, the TaqMan assays for North American EEE and WEE viral RNAs are the most sensitive. We have shown these assays to be specific for North American EEE and WEE viral RNAs by testing geographically and temporally distinct strains of EEE and WEE viruses along with a battery of related and unrelated arthropodborne viruses. In addition, all three types of nucleic acid amplification assays have been used to detect North American EEE and WEE viral RNAs from mosquito and vertebrate tissue samples. The sensitivity, specificity, and rapidity of nucleic acid amplification demonstrate the usefulness of NASBA, standard RT-PCR, and TaqMan assays, in both research and diagnostic settings, to detect North American EEE and WEE viral RNAs. PMID:12517876

  1. Early 21st century climatology of snow cover for the western river basins of the Indus River System: effects of changes on hydrological balance and society.

    Science.gov (United States)

    Hasson, Shabeh; Lucarini, Valerio; Riaz Khan, Mobushir; Petitta, Marcello; Bolch, Tobias; Gioli, Giovanna

    2014-05-01

    In this study we assess the snow cover and its dynamics for the western river basins of the Indus River System (IRS) and their sub-basins located in Afghanistan, China, India and Pakistan for the period 2001-2012. Moderate Resolution Imaging Spectro-radiometer (MODIS) daily snow products from Terra (MOD) and Aqua (MYD) have been first improved and then analysed on seasonal and annual basis against different topographic parameters (aspect, elevation and slope). Our applied cloud filtering technique has reduced the cloud cover from 37% (MOD) and 43% (MYD) to 7%, thus improving snow cover estimates from 7% (MOD) and 5% (MYD) to 14% for the area of interest (AOI) during the validation period (2004). Our results show a decreasing tendency for the annual average snow cover for the westerlies-influenced basins (Upper Indus Basin, Astore, Hunza, Shigar, Shyok) and an increasing tendency for the monsoon-influenced basins (Jhelum, Kabul, Swat and Gilgit). Regarding the seasonal snow cover, decrease during winter and autumn and increase during spring and summer has been found, which is consistent with the observed cooling and warming trends during the respective seasons. Sub-basins at relatively higher latitude/altitude show higher variability than basins at lower latitude/mid-altitude. Northeastern and northwestern aspects feature larger snow cover. The mean regional snow line altitude (SLA) zones range between 3000 and 5000 m a.s.l. for all basins. Our analysis provides an indication of a decrease in the regional SLA zone, thus indicating a change in the water resources of the studied basins, particularly for the Upper Indus Basin (UIB). Such results are consistent with the observed hydro-climate data, recently collected local perceptions and glacier mass balances for the investigated period. Moreover, our analysis suggests some potential for the seasonal stream flow forecast as a significant negative correlation has been detected for the inter-annual variability of winter

  2. Fossil associations from the middle and upper Eocene strata of the Pamplona Basin and surrounding areas (Navarre, western Pyrenees)

    OpenAIRE

    Astibia, H.; Tosquella Angrill, Josep

    2016-01-01

    Fossil associations from the middle and upper Eocene (Bartonian and Priabonian) sedimentary succession of the Pamplona Basin are described. This succession was accumulated in the western part of the South Pyrenean peripheral foreland basin and extends from deep-marine turbiditic (Ezkaba Sandstone Formation) to deltaic (Pamplona Marl, Ardanatz Sandstone and Ilundain Marl formations) and marginal marine deposits (Gendulain Formation). The micropalaeontological content is high. It is do...

  3. Tectonic structure, seismic stratigraphy and hydrocarbon potential of the North Kara Basin (Russian Arctic)

    Science.gov (United States)

    Verzhbitsky, V.; Kosenkova, N.; Murzin, R.; Vasilyev, V.; Malysheva, S.; Komissarov, D.; Ananyev, V.; Roslov, Yu.; Khudoley, A.

    2012-04-01

    North Kara shelf represents one of the remote and still poorly studied sedimentary megabasins of Russian West Arctic. North Kara area lacks any offshore wells so the understanding of its structure is based on the geology of adjacent East Barents Basin, as well as surrounding land areas (Taimyr, Severnaya and Novaya Zemlya fold belts) and stratigraphic columns of the scattered Arctic Islands. It is widely believed that North Kara shelf is mostly composed of Riphean-Paleozoic sedimentary units, underlain by Precambrian basement (North Kara massif), and represents one of the most promising areas of the Russian Arctic for hydrocarbon (mostly oil) discoveries. Our study is based on the reinterpretation of several regional seismic lines acquired by Sevmorgeo. We used the main Paleozoic and Mesozoic tectonic events known for Severnaya Zemlya Archipelago and Taimyr Peninsula for interpretation of the age of main seismic complexes/boundaries within the North Kara sedimentary cover (first of all within the Priseverozemelsky Trough). We correlated the sharp angular unconformity in the lower part of sedimentary succession with Cambrian/Ordovician unconformity described earlier on the nearby Severnaya Zemlya onshore domain. It is likely that the pre-Ordovician tectonic event corresponds to the Late Baikalian (Timanian) orogeny, which took place on Timan-Pechora and Novaya Zemlya areas. Above the unconformity we proposed the occurrence of Ordovician-Silurian shelfal sedimentary sequence of ~ 2 km thickness. This strata are overlain by thick (~3-4 km) progradational unit. It is likely that this sequence should correspond to molassic deposits of old red sandstones, related to the regional Caledonian orogeny. We believe that general structural pattern of the North Kara region was formed in Late Carboniferous-Early Permian time as a result of Kara massif/Siberian Craton collision-related Hercynian orogeny of Taimyr-Severnaya Zemlya domain. This event led to gentle folding of the

  4. 2009 Spring floods in North Dakota, western Minnesota, and northeastern South Dakota

    Science.gov (United States)

    Macek-Rowland, Kathleen M.; Gross, Tara A.

    2011-01-01

    In 2009, record-breaking snowfalls and additional spring moisture caused severe flooding in parts of the Missouri River and Red River of the North (Red River) Basins in North Dakota, Minnesota, and South Dakota. There were 48 peak of record stages and 36 discharges recorded at U.S. Geological Survey streamgages located in both basins between March 20 and May 15, 2009. High water continued to affect many communities up and down the rivers' main stems and tributaries for nearly 2 months. Record snowfall for single-day totals, as well as monthly totals, occurred throughout the Missouri River and Red River of the North Basins. Additional moisture in the spring as well as the timing of warmer temperatures caused record flooding in many places in both basins with many locations reporting two flood crests. Ice jams on the Missouri River, located north and south of Bismarck, N. Dak., caused flooding. Southwest Bismarck was evacuated as rising waters first began inundating homes in low-lying areas along the river and then continued flowing into the city's lower south side. On March 24, 2009, the peak stage of the Missouri River at Bismarck, N. Dak. streamgage was 16.11 feet, which was the highest recorded stage since the completion of Garrison Dam in 1954. South of Bismarck, the Missouri River near Schmidt, N. Dak. streamgage recorded a peak stage of 24.24 feet on March 25, 2009, which surpassed the peak of record of 23.56 feet that occurred on December 9, 1976. While peak stage reached record levels at these streamgages, the discharge through the river at these locations did not reach record levels. The record high stages resulted from ice jams occurring on the Missouri River north and south of the cities of Bismarck and Mandan. At the Red River of the North at Fargo, N. Dak. streamgage, the Red River reached a record stage of 40.84 feet surpassing the previous peak of record stage of 39.72 feet set in 1997. The associated peak streamflow of 29,500 cubic feet per second

  5. Prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon

    Science.gov (United States)

    Oh, Hyoeun; Ha, Kyung-Ja

    2016-10-01

    Intraseasonal monsoon prediction is the most imperative task, but there remains an enduring challenge in climate science. The present study aims to provide a physical understanding of the sources for prediction of dominant intraseasonal modes in the East Asian-western North Pacific summer monsoon (EA-WNPSM): pre-Meiyu&Baiu, Changma&Meiyu, WNPSM, and monsoon gyre modes classified by the self-organizing map analysis. Here, we use stepwise regression to determine the predictors for the four modes in the EA-WNPSM. The selected predictors are based on the persistent and tendency signals of the sea surface temperature (SST)/2m air temperature and sea level pressure fields, which reflect the asymmetric response to the El Niño Southern Oscillation (ENSO) and the ocean and land surface anomalous conditions. For the pre-Meiyu&Baiu mode, the SST cooling tendency over the western North Pacific (WNP), which persists into summer, is the distinguishing contributor that results in strong baroclinic instability. A major precursor for the Changma&Meiyu mode is related to the WNP subtropical high, induced by the persistent SST difference between the Indian Ocean and the western Pacific. The WNPSM mode is mostly affected by the Pacific-Japan pattern, and monsoon gyre mode is primarily associated with a persistent SST cooling over the tropical Indian Ocean by the preceding ENSO signal. This study carries important implications for prediction by establishing valuable precursors of the four modes including nonlinear characteristics.

  6. Gas-and water-saturated conditions in the Piceance Basin, Western Colorado: Implications for fractured reservoir detection in a gas-centered coal basin

    Energy Technology Data Exchange (ETDEWEB)

    Hoak, T.E.; Decker, A.D.

    1995-10-01

    Mesaverde Group reservoirs in the Piceance Basin, Western Colorado contain a large reservoir base. Attempts to exploit this resource base are stymied by low permeability reservoir conditions. The presence of abundant natural fracture systems throughout this basin, however, does permit economic production. Substantial production is associated with fractured reservoirs in Divide Creek, Piceance Creek, Wolf Creek, White River Dome, Plateau, Shire Gulch, Grand Valley, Parachute and Rulison fields. Successful Piceance Basin gas production requires detailed information about fracture networks and subsurface gas and water distribution in an overall gas-centered basin geometry. Assessment of these three parameters requires an integrated basin analysis incorporating conventional subsurface geology, seismic data, remote sensing imagery analysis, and an analysis of regional tectonics. To delineate the gas-centered basin geometry in the Piceance Basin, a regional cross-section spanning the basin was constructed using hydrocarbon and gamma radiation logs. The resultant hybrid logs were used for stratigraphic correlations in addition to outlining the trans-basin gas-saturated conditions. The magnitude of both pressure gradients (paludal and marine intervals) is greater than can be generated by a hydrodynamic model. To investigate the relationships between structure and production, detailed mapping of the basin (top of the Iles Formation) was used to define subtle subsurface structures that control fractured reservoir development. The most productive fields in the basin possess fractured reservoirs. Detailed studies in the Grand Valley-Parachute-Rulison and Shire Gulch-Plateau fields indicate that zones of maximum structural flexure on kilometer-scale structural features are directly related to areas of enhanced production.

  7. Mitochondrial DNA and prehistoric settlements: native migrations on the western edge of North America.

    Science.gov (United States)

    Eshleman, Jason A; Malhi, Ripan S; Johnson, John R; Kaestle, Frederika A; Lorenz, Joseph; Smith, David Glenn

    2004-02-01

    We analyzed previously reported mtDNA haplogroup frequencies of 577 individuals and hypervariable segment 1 (HVS1) sequences of 265 individuals from Native American tribes in western North America to test hypotheses regarding the settlement of this region. These data were analyzed to determine whether Hokan and Penutian, two hypothesized ancient linguistic stocks, represent biological units as a result of shared ancestry within these respective groups. Although the pattern of mtDNA variation suggests regional continuity and although gene flow between populations has contributed much to the genetic landscape of western North America, some evidence supports the existence of both the Hokan and Penutian phyla. In addition, a comparison between coastal and inland populations along the west coast of North America suggests an ancient coastal migration to the New World. Similarly high levels of haplogroup A among coastal populations in the Northwest and along the California coast as well as shared HVS1 sequences indicate that early migrants to the New World settled along the coast with little gene flow into the interior valleys.

  8. River Gain and Loss Studies for the Red River of the North Basin, North Dakota and Minnesota

    Science.gov (United States)

    Williams-Sether, Tara

    2004-01-01

    The Dakota Water Resources Act passed by the U.S. Congress in 2000 authorized the Secretary of the Interior to conduct a comprehensive study of future water-quantity and -quality needs of the Red River of the North (Red River) Basin in North Dakota and of possible options to meet those water needs. To obtain the river gain and loss information needed to properly account for available streamflow within the basin, available river gain and loss studies for the Sheyenne, Turtle, Forest, and Park Rivers in North Dakota and the Wild Rice, Sand Hill, Clearwater, South Branch Buffalo, and Otter Tail Rivers in Minnesota were reviewed. Ground-water discharges for the Sheyenne River in a reach between Lisbon and Kindred, N. Dak., were about 28.8 cubic feet per second in 1963 and about 45.0 cubic feet per second in 1986. Estimated monthly net evaporation losses for additional flows to the Sheyenne River from the Missouri River ranged from 1.4 cubic feet per second in 1963 to 51.0 cubic feet per second in 1976. Maximum water losses for a reach between Harvey and West Fargo, N. Dak., for 1956-96 ranged from about 161 cubic feet per second for 1976 to about 248 cubic feet per second for 1977. Streamflow gains of 1 to 1.5 cubic feet per second per mile were estimated for the Wild Rice, Sand Hill, and Clearwater Rivers in Minnesota. The average ground-water discharge for a 5.2-mile reach of the Otter Tail River in Minnesota was about 14.1 cubic feet per second in August 1994. The same reach lost about 14.1 cubic feet per second between February 1994 and June 1994 and about 21.2 cubic feet per second between August 1994 and August 1995.

  9. Paleogeographic and tectonic controls on the evolution of Cenozoic basins in the Altiplano and Western Cordillera of southern Peru

    Science.gov (United States)

    Carlotto, Víctor

    2013-03-01

    Integrated studies of stratigraphy, sedimentology, paleogeography and tectonic controls on Cenozoic basins provide the basis for a series of time-slice reconstructions of basin evolution in the Andes of southern Peru. The Altiplano and adjacent margin of the Western Cordillera are characterized by several Paleocene-Miocene synorogenic continental basins with thicknesses locally exceeding 10 km. The evolution of these basins has been controlled by NW-trending tectonic features that mark the Altiplano-Western Cordillera and Altiplano-Eastern Cordillera boundaries and the Condoroma structural high. Sedimentary deposits of Paleocene age preserved in the Altiplano are the result of nonmarine sedimentation in a distal foreland basin. During the early Eocene, predominantly dextral strike-slip movements in the Altiplano between the Cusco-Lagunillas and Urcos-Ayaviri fault systems created the transpressional Kayra basin. The Soncco and Anta basins (middle Eocene-early Oligocene) are related to NE shortening (43-30 Ma) and represent proximal, wedge-top and foredeep basin environments preserved on the Altiplano. At ~ 29-28 Ma, a change to predominantly E-W shortening produced sinistral strike-slip motion along NW-striking faults, resulting in intermontane, transpressional basins. In the Altiplano, the Tinajani and Punacancha (29-5 Ma), and Paruro (12-6 Ma) basins were controlled by the Cusco-Lagunillas and the Urcos-Ayaviri fault systems. The Maure, Tincopalca-Huacochullo and Condoroma basins (22-5 Ma) of the Western Cordillera developed between the Condoroma high and the Cusco-Lagunillas fault system. Oligocene-Miocene sedimentation commonly evolved from proximal (alluvial) facies along the borders to distal (lacustrine) facies. These basins were linked to sinistral strike-slip faults that evolved into reverse-sinistral structures. Plate kinematics may play a role in Andean basin evolution, with deformation influenced by major preexisting faults that dictated paleogeographic

  10. Complex tectonic and tectonostratigraphic evolution of an Alpine foreland basin: The western Duero Basin and the related Tertiary depressions of the NW Iberian Peninsula

    Science.gov (United States)

    Martín-González, F.; Heredia, N.

    2011-04-01

    The tectonic and tectonostratigaphic evolution of foreland basins and related Tertiary depressions are the key to investigate deformation history and the uplifting of the continental lithosphere of the Alpine-Pyrenean Orogeny. The northern part of the Duero basin is the foreland basin of the Cantabrian Mountains, which are, in turn, the western part of the Pyrenean Orogen. We have studied the western sharp end of the Duero foreland basin, and its relation to the Tertiary deposits of the NW Iberian Peninsula and the topography evolution. In order to propose a coherent tectonic and tectonosedimentary model that could explain all Tertiary deposits, we have analysed the depositional environment, stratigraphic sequences, paleocurrents and established a correlation of the main outcrops. Besides, a detailed structural mapping of the Alpine structures that limit and affect the main Tertiary outcrops has been carried out. The Tertiary deposits of the NW Iberian Peninsula depressions are affected and fragmented by Alpine structures that limit their extensions and locations. The stratigraphic succession is similar in the NW Tertiary outcrops; they are mainly terrigenous and carbonated continental deposits formed by assemblage of alluvial fans developed at the mountains front, in arid or semiarid conditions. Three formations can be identified in the main depressions: Toral Fm, Santalla Fm and Médulas Fm. The NW Tertiary outcrops were the western deposits of the Duero foreland basin that surrounded the lateral termination of the Pyrenean Orogen. These deposits were fragmented and eroded by the subsequent uplift of the Galaico-Leoneses Mountains and the NE-SW strike-slip faults activity (broken foreland basin). Only the latest stages of some of these outcrops can be considered as intramontane basins as traditionally have been interpreted. The sedimentation started in the northeast (Oviedo-Infiesto) during the Eocene and migrated to the west (As Pontes) during the Late Oligocene

  11. 137Cs vertical distribution at the deep basins of the North and Central Aegean Sea, Greece

    International Nuclear Information System (INIS)

    Large volume seawater samples were collected for the determination of 137Cs concentration along with depth in the deep basins of North and Central Aegean Sea. The vertical 137Cs distribution showed maximum concentration at the bottom of the basins, while the minimum values corresponded to the intermediate layer, where Levantine water exists. The surface 137Cs activity is found to lie between the two limits and is originated from the Black Sea waters. The typical oceanographic advection–diffusion balance model is modified to a diffusion-settling-decay balance model to better understand the vertical distribution and variation of the 137Cs concentration in the deep basins. In addition, the diffusivity of each basin, as well as the settling speed of particulate 137Cs is also estimated. The results are compared with theoretical approach as well as with previous data. - Highlights: • Three deep basins were studied using 137Cs as a tracer. • Deep waters constitute 137Cs repositories due to deep water formation followed Chernobyl accident. • Diffusivities, as well as particulate 137Cs settling speeds are estimated

  12. South China connected to north India in Gondwana: sedimentary basin and detrital provenance analyses

    Science.gov (United States)

    Yao, W.; Li, Z. X.; Li, W. X.; Li, X. H.; Yang, J. H.

    2015-12-01

    The paleoposition of South China during the Ediacaran-Silurian is important for understanding the assembly of Gondwana. We report here the tectonostratigraphic evolution of the Ediacaran-Silurian Nanhua foreland basin in South China, and discuss South China's connection with Gondwana and potential tectonic triggers for both the Wuyi-Yunkai orogeny in South China and the Bhimphedian orogeny in north India. The Nanhua basin was involved in a three-stage evolution, which are: Stage 1 (the Ediacaran-Cambrian) recording the start of tectonic subsidence with turbiditic marine clastic deposition, fed by exotic orogens outboard South China; Stage 2 (the Ordovician to earliest-Silurian) featured by migrating depocentres with dominant shallow marine to deltaic clastic deposition, fed by the local Wuyi-Yunkai orogen; and Stage 3 (the Silurian) showing the arrival of depocentre in the Yangtze Block during the waning stage of the Wuyi-Yunkai orogeny with deltaic deposition in the remanent foreland basin. Detrital zircon analyses of the Ediacaran-Silurian sandstones across the Nanhua basin reveal a prominent age population of 1100-900 Ma (with a peak age at ~980 Ma) and moderate populations of Archean-Paleozoic ages, grossly matching that of crystalline and sedimentary rocks in northern India. Zircon isotopes of the Stage 1 samples suggest three Precambrian episodes of juvenile crustal growth at 3.0 Ga, 2.5 Ga and 1.0 Ga, and a major crustal reworking at 580-500 Ma for the source areas, which are constraint to be northwestern India and its surrounding orogens. Together with other evidence, we propose that South China likely collided with northwestern India during the Gondwana assembly, generated the Bhimphedian orogeny in north India and formed two foreland basins on both the north India and South China sides. Far-field stress of the collision triggered the Ordovician-Silurian Wuyi-Yunkai orogeny in South China. The Stage 2-3 samples in the Nanhua basin of South China were shed

  13. A systematic regional trend in helium isotopes across the northernbasin and range province, Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, B. Mack; van Soest, Matthijs C.

    2006-05-01

    An extensive study of helium isotopes in fluids collectedfrom surface springs, fumaroles and wells across the northern Basin andRange Province reveals a systematic trend of decreasing 3He/4He ratiosfrom west to east. The western margin of the Basin and Range ischaracterized by mantle-like ratios (6-8 Ra) associated with active orrecently active crustal magma systems (e.g., Coso, Long Valley,Steamboat, and the Cascade volcanic complex). Moving towards the east,the ratios decline systematically to a background value of ~;0.1 Ra. Theregional trend is consistent with extensive mantle melting concentratedalong the western margin and is coincident with an east-to-west increasein the magnitude of northwest strain. The increase in shear strainenhances crustal permeability resulting in high vertical fluid flow ratesthat preserve the high helium isotope ratios at the surface. Superimposedon the regional trend are "helium spikes," local anomalies in the heliumisotope composition. These "spikes" reflect either local zones of mantlemelting or locally enhanced crustal permeability. In the case of theDixie Valley hydrothermal system, it appears to be a combination ofboth.

  14. THE RELATIONSHIP BETWEEN GLOBAL WARMING AND THE VARIATION IN TROPICAL CYCLONE FREQUENCY OVER THE WESTERN NORTH PACIFIC

    Institute of Scientific and Technical Information of China (English)

    MA Li-ping; CHEN Lian-shou

    2009-01-01

    The relationship between global warming and the variation in tropical cyclone (TC) genesis frequency is analyzed using the data of the Tropical Cyclone Year Book by the China Meteorological Administration and the National Centers for Environmental Prediction (NCEP) reanalysis data from 1949 to 2007. The observational results indicate that the average sea surface temperature (SST) in the Intertropieal Convergence Zone (ITCZ) region (10°N - 20°N,100°E - 140°E) increases by 0.6°C against thc background of global warming,while the frequency of tropical cyclone geneses in this region decreases significantly. Generally,the rise of SSTs is favorable tbr the genesis of tropical cyclones,but it is now shown to be contrary to the normal cffect. Most of the tropical cyclones in the western North Pacific (WNP) are generated in the ITCZ. This is quite different from the case in the Atlantic basin in which the tropical cyclones are mostly generated from thc easterly wave. Our research results demonstrate that the ITCZ has a weakening trend in strength,and it has moved much more equatorward in the past 40 years; both are disadvantageous to the fbrmation of tropical cyclones. Furthermore,our study also found that the ridge of the subtropical high tends to shift slightly equatorward,which is another adverse mechanism for the formation of tropical cyclones.

  15. First observations on the abundance and composition of floating debris in the North-western Black Sea.

    Science.gov (United States)

    Suaria, Giuseppe; Melinte-Dobrinescu, Mihaela C; Ion, Gabriel; Aliani, Stefano

    2015-06-01

    The occurrence of marine litter in the Black Sea region is poorly known and even less data have been reported on the abundance of floating debris. Here we present results from a ship-based visual survey carried out in the North-Western part of the Black Sea, providing the first preliminary data on the characteristics of floating debris in Romanian waters. High litter densities peaking to 135.9 items/km(2) were found in the study area (mean 30.9 ± 7.4 items/km(2)). Probably due to the proximity of the Danube delta, natural debris were on average, much more abundant than anthropogenic litter in most surveyed locations (mean 141.4 ± 47.1 items/km(2), max 1131.3 items/km(2)). Most of the 225 objects we sighted consisted of pieces of wood and other riparian debris (75.5%), however plastic items remained undoubtedly the most abundant type of litter, representing 89.1% of all sighted man-made items. The Black Sea is not exempt from the global invasion of floating debris, however data are still lacking and a basin-wide survey is urgently needed to identify accumulation areas and develop regionally effective solutions to the problem of marine litter. PMID:25881011

  16. First sero-prevalence of dengue fever specific immunoglobulin G antibodies in Western and North-Western provinces of Zambia: a population based cross sectional study

    OpenAIRE

    Mazaba-Liwewe, Mazyanga Lucy; Siziya, Seter; Monze, Mwaka; Mweene-Ndumba, Idah; Masaninga, Freddie; Songolo, Peter; Malama, Costantine; Chizema, Elizabeth; Mwaba, Peter; Babaniyi, Olusegun A

    2014-01-01

    Background Dengue fever is a tropical infectious disease caused by dengue virus (DENV), a single positive-stranded RNA Flavivirus. There is no published evidence of dengue in Zambia. The objective of the study was to determine the sero-prevalence and correlates for dengue fever specific IgG antibodies in Western and North-Western provinces in Zambia. Methods A randomized cluster design was used to sample participants for yellow fever risk assessment. In order to rule out cross reactivity with...

  17. Peak Flow Responses to Clear-Cutting and Roads in Small and Large Basins, Western Cascades, Oregon

    Science.gov (United States)

    Jones, J. A.; Grant, G. E.

    1996-04-01

    This study quantified long-term changes in streamflows associated with clear-cutting and road construction and examined alternative hydrologic mechanisms to explain stream hydrograph changes in the Cascades Range, western Oregon. We examined differences in paired peak discharges for 150 to 375 storm events for five basin pairs, using 34-year records from two pairs of 60-to-101-ha experimental basins in the H. J. Andrews Experimental Forest, and 50-to-55-year records from three pairs of adjacent basins ranging from 60 to 600 km2. Forest harvesting has increased peak discharges by as much as 50% in small basins and 100% in large basins over the past 50 years. These increases are attributable to changes both in flow routing due to roads and in water balance due to treatment effects and vegetation succession.

  18. The Inland Penetration of Atmospheric Rivers over Western North America: A Lagrangian Analysis

    Science.gov (United States)

    Rutz, J. J.; Steenburgh, W. J.; Ralph, F. M.

    2014-12-01

    Although atmospheric rivers (ARs) typically weaken following landfall, those that penetrate inland can contribute to heavy precipitation and high-impact weather within the interior of western North America. In this paper, we examine the evolution of ARs over western North America using trajectories released at 950 and 700 hPa within cool-season ARs along the Pacific coast. These trajectories are classified as coastal decaying, inland penetrating, or interior penetrating based on whether they remain within an AR upon reaching selected transects over western North America. Interior-penetrating AR trajectories most frequently make landfall along the Oregon coast, but the greatest fraction of landfalling AR trajectories that eventually penetrate into the interior is found along the Baja Peninsula. In contrast, interior-penetrating trajectories rarely traverse the southern "high" Sierra. At landfall, interior-penetrating trajectories are associated with a more amplified flow pattern, more southwesterly (vs. westerly) flow along the Pacific coast, and larger water vapor transport (qu). The larger initial qu of interior-penetrating trajectories is due primarily to larger initial water vapor (q) and wind speed (u) for those initiated at 950 and 700 hPa, respectively. Inland- and interior-penetrating AR trajectories maintain large qu over the interior due partially to increases in u that offset decreases in q, particularly in the vicinity of topographical barriers. Therefore, synoptic conditions and trajectory pathways favoring larger initial qu at the coast, limited water vapor depletion by orographic precipitation, and increases in u over the interior are keys to differentiating interior-penetrating from coastal-decaying AR trajectories.

  19. Past climate change and plant evolution in Western North America: a case study in Rosaceae.

    Directory of Open Access Journals (Sweden)

    Mats Töpel

    Full Text Available Species in the ivesioid clade of Potentilla (Rosaceae are endemic to western North America, an area that underwent widespread aridification during the global temperature decrease following the Mid-Miocene Climatic Optimum. Several morphological features interpreted as adaptations to drought are found in the clade, and many species occupy extremely dry habitats. Recent phylogenetic analyses have shown that the sister group of this clade is Potentilla section Rivales, a group with distinct moist habitat preferences. This has led to the hypothesis that the ivesioids (genera Ivesia, Horkelia and Horkeliella diversified in response to the late Tertiary aridification of western North America. We used phyloclimatic modeling and a fossil-calibrated dated phylogeny of the family Rosaceae to investigate the evolution of the ivesioid clade. We have combined occurrence- and climate data from extant species, and used ancestral state reconstruction to model past climate preferences. These models have been projected into paleo-climatic scenarios in order to identify areas where the ivesioids may have occurred. Our analysis suggests a split between the ivesioids and Potentilla sect. Rivales around Late Oligocene/Early Miocene (∼23 million years ago, Ma, and that the ivesioids then diversified at a time when summer drought started to appear in the region. The clade is inferred to have originated on the western slopes of the Rocky Mountains from where a westward range expansion to the Sierra Nevada and the coast of California took place between ∼12-2 Ma. Our results support the idea that climatic changes in southwestern North America have played an important role in the evolution of the local flora, by means of in situ adaptation followed by diversification.

  20. Dispersion of radionuclides in the European north-western seas: observations and modelling

    International Nuclear Information System (INIS)

    In this report for an Accreditation to supervise research (HDR), the author reports the use over 30 years by the Cherbourg-Octeville IRSN Laboratory of artificial radionuclides in solution in sea water as oceanographic markers. Such measurements on radio-markers which are soluble in sea water, enabled a better knowledge of dissolved substance displacements in north-western seas of Europe, notably the Channel, the North Sea, the Celtic Sea, and the Irish Sea. The author reports researches which aimed at studying the dispersion of radionuclides in seawater and their use as water mass markers, at validating hydrodynamic models of dispersion at different time-space scales, at the understanding and simulation of the sedimentary transport, and at studying the transfer to living species. These different topics give the document its structure

  1. Food composition of some low altitude Lissotriton montandoni (Amphibia, Caudata populations from North-Western Romania

    Directory of Open Access Journals (Sweden)

    Covaciu-Marcov S.D.

    2010-01-01

    Full Text Available The diet of some populations of Lissotriton montandoni from north-western Romania is composed of prey belonging to 20 categories. The food components of the Carpathian newts are similar to those of other species of newts. Most of the prey are aquatic animals, but terrestrial prey also has a high percentage abundance. The consumed prey categories are common in the newts' habitats as well, but in natural ponds the prey item with the highest abundance in the diet is not the most frequent one in the habitat. Thus, although the Carpathian newts are basically opportunistic predators, they still display a certain trophic selectivity.

  2. Interdecadal variability of the tropospheric biennial oscillation in the western North Pacific

    Institute of Scientific and Technical Information of China (English)

    Zheng Bin; Lin Ai-Lan; Gu De-Jun; Li Chun-Hui

    2008-01-01

    The observed tropospheric biennial oscillation (TBO) in the western North Pacific (WNP) monsoon region has an interdecadal variability with a period of 40-50 yr.That suggests a weaker effect of the TBO on the East Asia followed by a stronger one.A simple analytic model was designed to investigate the mechanism of the interdecadal variability of the TBO.The results indicated that a local TBO air-sea system not only supports the TBO variability in the WNP monsoon region but also produces an interdecadal variability of the TBO.

  3. Literature and information related to the natural resources of the North Aleutian Basin of Alaska.

    Energy Technology Data Exchange (ETDEWEB)

    Stull, E.A.; Hlohowskyj, I.; LaGory, K. E.; Environmental Science Division

    2008-01-31

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant natural resources. The Basin includes most of the southeastern part of the Bering Sea Outer Continental Shelf, including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals, including several federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, 'Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012' and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory were contracted to assist MMS with identifying and prioritizing information needs related to potential future oil and gas leasing and development activities in the North Aleutian Basin. Argonne focused on three related tasks: (1) identify and gather relevant literature published since 1996, (2) synthesize and

  4. Relationships between the tropical SST and summertime subtropical high over the western North Pacific

    Science.gov (United States)

    Chung, Pei-Hsuan; Sui, Chung-Hsiung; Li, Tim

    2010-05-01

    The interannual variability of the western North Pacific Subtropical High (WNPSH) in summer is investigated with the use of the NCEP/NCAR reanalysis data for the period of 1958-2005. The most significant change appears at the western edge of WNPSH, with dominant 2-3-yr and 3-5-yr power spectrum peaks. The 2-3-yr oscillation of WNPSH and associated circulation and sea surface temperature (SST) patterns possess a coherent eastward-propagating feature, with a warm SST anomaly (SSTA) and anomalous ascending motion migrating from the tropical Indian Ocean in the preceding winter to the maritime continent in the concurrent summer of a strong WNPSH. A strong WNPSH is characterized by anomalous anticyclonic circulation and maximum subsidence in the western North Pacific (WNP). The anomalous WNPSH circulation has an equivalent barotropic vertical structure and resides in the sinking branch of local Hadley circulation, triggered by enhanced convection over the maritime continent in the summer. A heat budget analysis reveals that WNPSH is maintained by radiative cooling, which overcomes the decent induced adiabatic warming. The 3-5-yr oscillation of WNPSH exhibits a quasi stationary feature, with a warm SSTA (anomalous ascending motion) located in the equatorial central-eastern Pacific and Indian Ocean and a cold SSTA (anomalous descending motion) located in the western Pacific. The anomaly pattern persists from the preceding winter to the concurrent summer of a high WNPSH. The maximum descent is located to the east of the anomalous anticyclone center, where a baroclinic vertical structure is identified. The anomalous anticyclone on this timescale is a Rossby wave response to a negative convective heating associated with the local cold SSTA.

  5. Ceramic clays from the western part of the Tamnava Tertiary Basin, Serbia: Deposits and clay types

    Directory of Open Access Journals (Sweden)

    Radosavljević Slobodan

    2014-01-01

    Full Text Available Based on geological, mineralogical, physical, chemical and technological investigations in the Tamnava Tertiary Basin near Šabac town (western Serbia, deposits of ceramic clays were studied. These ceramic clays are composed of kaolin-illite with a variable content of quartz, feldspars, mica, iron oxides and hydroxides, and organic matter. Four main types of commercial clays were identified: i red-yellow sandy-gravely (brick clays; ii grey-white poor sandy (ceramic clays; iii dark-carbonaceous (ceramic clays; and iv lamellar (“interspersed” fatty, poor sandy (highly aluminous and ferrous clays. Ceramic clays are defined as medium to high plastic with different ranges of sintering temperatures, which makes them suitable for the production of various kinds of materials in the ceramic industry. [Projekat Ministarstva nauke Republike Srbije, br. OI-176016

  6. A Reassessment of the Integrated Impact of Tropical Cyclones on Surface Chlorophyll in the Western Subtropical North Atlantic

    Energy Technology Data Exchange (ETDEWEB)

    Foltz, Gregory R.; Balaguru, Karthik; Leung, Lai-Yung R.

    2015-02-28

    The impact of tropical cyclones on surface chlorophyll concentration is assessed in the western subtropical North Atlantic Ocean during 1998–2011. Previous studies in this area focused on individual cyclones and gave mixed results regarding the importance of tropical cyclone-induced mixing for changes in surface chlorophyll. Using a more integrated and comprehensive approach that includes quantification of cyclone-induced changes in mixed layer depth, here it is shown that accumulated cyclone energy explains 22% of the interannual variability in seasonally-averaged (June–November) chlorophyll concentration in the western subtropical North Atlantic, after removing the influence of the North Atlantic Oscillation (NAO). The variance explained by tropical cyclones is thus about 70% of that explained by the NAO, which has well-known impacts in this region. It is therefore likely that tropical cyclones contribute significantly to interannual variations of primary productivity in the western subtropical North Atlantic during the hurricane season.

  7. Comparative Study of Basins within Palaeogene Seaway in East China and Cretaceous Seaway in North America and Its Reservoir Significance

    Institute of Scientific and Technical Information of China (English)

    Wu Xiantao

    2007-01-01

    The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite sides of North Pacific Ocean may be not a coincidence,and a comparative study was made in this paper. The results show that the two seaways inundated basins share several similarities particularly in basin origin,filling processes and reservoir facies. It is suggested that reservoir facies of estuarine sandstone and shelf bar sandstone related to sea level fluctuation,which are well developed in the Cretaceous seaway covered basins in North America might have been also developed here in Palaeogene seaway inundated basins in East China. Therefore it is worth paying more attention to finding these new reservoir facies on this side of the Pacific ocean. Evidences of sedimentology and ichnology indicate that good prospects are likely.

  8. The Sulfur content and origin of the North Thrace Basin coals, Turkey

    Science.gov (United States)

    Erarslan, Cemile; Örgün, Yüksel; Çelik Balcı, Nurgül

    2016-04-01

    Sulfur (S) is one of the major and hazardous components of the coal, and it may be originated from different sources depending on coal formation. The defined main sulfur types in the coal are pyritic sulfur, organic sulfur and sulfate sulfur. Thrace basin which have approximately 2 billion tons coal reserves is one of the most important coal basins of Turkey and Edirkoy (Saray-Tekirdaǧ) is the largest coal production site in north of Thrace basin. The obtained results show that the total S contents in the Edirköy coal samples vary from 3.21 to 14.1%. According to this result, the coal in Edirköy field is in the form of high -sulfur coal and the sulfur types analysis indicate that the ratio of pyritic sulfur vary from 0.78 to 5.25%, the organic sulfur vary from 1.1 to 7.47 % and the sulfate sulfur vary from 0.54 to 1.38% in the field. It was revealed that the ratio of organic sulfur in the coal increase towards the north of the field. In this study, the sulfur content and origin of the coal in Edirköy field will be discussed with sulfur isotope data.

  9. Preliminary hydrologic budget studies, Indian Creek watershed and vicinity, Western Paradox Basin, Utah

    International Nuclear Information System (INIS)

    Preliminary quantitative estimates of ground-water discharge into the Colorado River System in the western Paradox Basin were prepared on the basis of existing climatological and streamflow records. Ground-water outflow to the river was deduced as a residual from hydrologic budget equations for two different study areas: (1) the region between gaging stations at Cisco, Green River, and Hite, Utah; and (2) the Indian Creek watershed. An empirical correlation between recharge rates and precipitation amounts derived for several basins in eastern Nevada was applied to estimate recharge amounts for the Indian Creek watershed. A simple Darcian flow model was then used to approximate the ground-water flux outward from the watershed for comparison. Salinity measurements in the Colorado River were also used to approximate ground-water outflow to a river reach in Cataract Canyon in order to provide another comparison with the hydrologic budget results. Although these estimates should be considered only gross approximations, all approaches used provide values of ground-water outflow that are much less than estimates of similar parameters provided by the US Geological Survey in recent hydrologic reconnaissance reports. Estimates contained herein will be refined in future numerical modeling and data collection studies

  10. Hydrogeological evolution of the Luni river basin, Rajasthan, western India: A review

    Indian Academy of Sciences (India)

    V N Bajpai

    2004-09-01

    The Luni river basin has been evolved as a result of typical hydrogeomorphic processes of arid zone, operating under the influence of active tectonic lineaments. A detailed analysis of stream morphology in relation to geology and lineaments carried out on selected windows indicated the morphological control of the streams while flowing over the lineaments from the eastern to the western part of the basin. Typical valley fills indicated by dark green tone on digitally processed images and the pediments showing greenish white tone appear in sharp contrast and indicate respectively the graben and horst structures. A detailed identification of lineaments for the georesources and geological evaluation has been carried out. Earlier analysis carried out on Bouguer anomalies correlate with graben and horst structures in the subsurface. Quaternary sequences have been dated from 80 ka to 3 ka indicating a range of fluvial to aeolian deposits reflecting prevailing climatic conditions. However, the changes in sediment type from coarse and mixed of all size grades to fine in a vertical litho-column warrant further studies on fine resolution stratigraphy and high resolution stratigraphy for understanding climatic variations in the region.

  11. Preliminary study on avian fauna of the Krishna River basin Sangli District, Western Maharashtra, India.

    Science.gov (United States)

    Kumbar, Suresh M; Ghadage, Abhijit B

    2014-11-01

    The present study on avifaunal diversity carried out for three years at the Krishna River Basin, Sangli District revealed a total of 126 species of birds belonging to 30 families, of which 91 species were resident, 16 migratory, 12 resident and local migratory and 7 species were resident and migratory. Among the migrant birds, Rosy Starling Sturnus roseus was dominant in the study area. Commonly recorded resident bird species were, Red vented bulbul, Jungle crow, House sparrow, Common myna, Brahminy myna, Rock pigeon, Spotted dove, Rose ringed parakeet, Indian robin, White-browed fantail-flycatcher and Small sunbird. Most of the families had one or two species, whereas Muscicapidae family alone had 16 species. Forty one species of waterfowls were recorded in this small landscape. Out of 126 bird species, 38 were insectivorous, 28 piscivorous, 25 omnivorous, 19 carnivorous, 9 granivorous, 5 frugivorous and 2 species were nectar sucker and insectivorous. These results suggest that richness of avifauna in the Krishna River Basin, Western Maharashtra might be due to large aquatic ground, varied vegetations and favourable environmental conditions. PMID:25522499

  12. Late Quaternary stratigraphic development in the lower Luni, Mahi and Sabarmati river basins, western India

    Indian Academy of Sciences (India)

    M Jain; S K Tandon; S C Bhatt

    2004-09-01

    This study reviews the Quaternary alluvial stratigraphy in three semi-arid river basins of western India i.e., lower Luni (Rajasthan), and Mahi and Sabarmati (Gujarat alluvial plains). On the basis of OSL chronologies, it is shown that the existing intra-valley lithostratigraphic correlations require a revision. The sand, gravel and mud facies are present during various times in the three basins, however, the fluvial response to climate change, and the resulting facies associations, was different in the Thar desert as compared to that at the desert margin; this makes purely lithostratigraphic correlations unviable. It is further shown that the rivers in the Thar desert were more sensitive to climate change and had small response times and geomorphic thresholds as compared to the desert-margin rivers. This is illustrated during the early OIS 1, when the Luni river in the Thar desert was dynamic and showed frequent variations in fluvial styles such as gravel bedload braided streams, sand-bed ephemeral streams and meandering streams, all followed by incision during the early Holocene. The coeval deposits in Sabarmati, however, only show a meandering, floodplain-dominated river. Late Quaternary alluvial deposits in these basins unconformably overlie some older deposits that lack any absolute chronology. Based on the facies types and their associations, and the composition and architecture of the multistoried gravel sheets in the studied sections, it is suggested that older deposits are of pre-Quaternary age. This hypothesis implies the presence of a large hiatus incorporating much of the Quaternary period in the exposed sections.

  13. Storing CO{sub 2} under the North Sea Basin - A key solution for combating climate change

    Energy Technology Data Exchange (ETDEWEB)

    Skogen, T; Morris, B; Agerup, M; Svenningsen, S Oe; Kropelien, K F; Solheim, M; Northmore, B; Dixon, T; O' Carroll, K; Greaves, A; Golder, J; Selmer-Olsen, S; Sjoeveit, A; Kaarstad, O; Riley, N; Wright, I; Mansfield, C

    2007-06-15

    This report represents the first deliverable of the North Sea Basin Task Force, which Norway and the UK established in November 2005 to work together on issues surrounding the transport and storage of CO{sub 2} beneath the North Sea. The North Sea represents the best geological opportunity for storing our CO{sub 2} emissions away from the atmosphere for both the UK and Norway

  14. Continental pollution in the Western Mediterranean basin: large variability of the aerosol single scattering albedo and influence on the direct shortwave radiative effect

    OpenAIRE

    Biagio, C.; Formenti, P.; Doppler, L.; C. Gaimoz; Grand, N.; Ancellet, G.; Attié, J.-L.; Bucci, S.; P. Dubuisson; Fierli, F.; Mallet, M.; Ravetta, F

    2016-01-01

    Pollution aerosols strongly influence the composition of the Western Mediterranean basin, but at present little is known on their optical properties. We report in this study in situ observations of the single scattering albedo (ω) of pollution aerosol plumes measured over the Western Mediterranean basin during the TRAQA (TRansport and Air QuAlity) airborne campaign in summer 2012. Cases of pollution export from different source regions around the basin and at different altitudes between ~160 ...

  15. Projected future changes in vegetation in western North America in the 21st century

    Science.gov (United States)

    Xiaoyan, Jiang; Rauscher, Sara A.; Ringler, Todd D.; Lawrence, David M.; Williams, A. Park; Allen, Craig D.; Steiner, Allison L.; Cai, D. Michael; McDowell, Nate G.

    2013-01-01

    Rapid and broad-scale forest mortality associated with recent droughts, rising temperature, and insect outbreaks has been observed over western North America (NA). Climate models project additional future warming and increasing drought and water stress for this region. To assess future potential changes in vegetation distributions in western NA, the Community Earth System Model (CESM) coupled with its Dynamic Global Vegetation Model (DGVM) was used under the future A2 emissions scenario. To better span uncertainties in future climate, eight sea surface temperature (SST) projections provided by phase 3 of the Coupled Model Intercomparison Project (CMIP3) were employed as boundary conditions. There is a broad consensus among the simulations, despite differences in the simulated climate trajectories across the ensemble, that about half of the needleleaf evergreen tree coverage (from 24% to 11%) will disappear, coincident with a 14% (from 11% to 25%) increase in shrubs and grasses by the end of the twenty-first century in western NA, with most of the change occurring over the latter half of the twenty-first century. The net impact is a ~6 GtC or about 50% decrease in projected ecosystem carbon storage in this region. The findings suggest a potential for a widespread shift from tree-dominated landscapes to shrub and grass-dominated landscapes in western NA because of future warming and consequent increases in water deficits. These results highlight the need for improved process-based understanding of vegetation dynamics, particularly including mortality and the subsequent incorporation of these mechanisms into earth system models to better quantify the vulnerability of western NA forests under climate change.

  16. Late Holocene record of sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California

    Science.gov (United States)

    McGann, M.; Paull, C. K.; Herguera, J. C.; Barron, J. A.; Gwiazda, R.; Anderson, K.; Lundsten, E. M.; Edwards, B. D.; Caress, D. W.

    2015-12-01

    Transects of ≤1.5 m-long vibracores obtained with MBARI's ROV Doc Ricketts reveal late Holocene sedimentologic and paleooceanographic events in western Guaymas Basin, Gulf of California (GOC) (~26.87°N, 111.338°W). Cores were located where layered near-seafloor sediments and subtle bedforms occur in 1793 to 1863 m water depths on the SW flank of the basin using detailed bathymetry and chirp profiles. Color banding was observed in the cores and gamma-density, XRF, grain size, and stable isotope data show that most of the banding is attributed to distal deposition from two turbidities. Distinctive white bands ~4 cm thick are present in three cores dispersed across ~300 m. The white bands are diatom oozes composed primarily of Thalassiothrix longissima as well as lesser abundances of Fragilariopsis doliolus and are probably a result of aggregations of Thalassiothrix-dominated mats that settle through the water column and accumulate on the seafloor. An AMS14C date taken ~3 cm above the white band in one core suggests this event occurred shortly before cal AD 1290±30. The core sites were most likely located beneath an important oceanographic front between nutrient-rich and oligotrophic water masses, probably as the result of well-mixed upper intermediate and surface waters in the mid-GOC and better-stratified tropical waters to the south. This implies the existence of a deeper mixed layer to the N in the mid GOC region most likely controlled by equatorial La Niña events fueled by stronger and more persistent NW winds along the GOC. A substantial reduction in diatom abundance evident by low specimen counts and lack of white bands following this mat-forming event seem to correlate with an abrupt decline in biosiliceous productivity and increases in the abundance of tropical diatoms and silicoflagellates in core MD02-2517 (887 m water depth; western Guaymas Basin slope) at the end of the Medieval Climate Anomaly and transition to the Little Ice Age (~AD 1200-1300).

  17. Modulation of western North Pacific tropical cyclone activity by the Atlantic Meridional Mode

    Science.gov (United States)

    Zhang, Wei; Vecchi, Gabriel A.; Villarini, Gabriele; Murakami, Hiroyuki; Rosati, Anthony; Yang, Xiaosong; Jia, Liwei; Zeng, Fanrong

    2016-05-01

    This study examines the year-to-year modulation of the western North Pacific (WNP) tropical cyclones (TC) activity by the Atlantic Meridional Mode (AMM) using both observations and the Geophysical Fluid Dynamics Laboratory Forecast-oriented Low Ocean Resolution Version of CM2.5 (FLOR) global coupled model. 1. The positive (negative) AMM phase suppresses (enhances) WNP TC activity in observations. The anomalous occurrence of WNP TCs results mainly from changes in TC genesis in the southeastern part of the WNP. 2. The observed responses of WNP TC activity to the AMM are connected to the anomalous zonal vertical wind shear (ZVWS) caused by AMM-induced changes to the Walker circulation. During the positive AMM phase, the warming in the North Atlantic induces strong descending flow in the tropical eastern and central Pacific, which intensifies the Walker cell in the WNP. The intensified Walker cell is responsible for the suppressed (enhanced) TC genesis in the eastern (western) part of the WNP by strengthening (weakening) ZVWS. 3. The observed WNPTC-AMM linkage is examined by the long-term control and idealized perturbations experiment with FLOR-FA. A suite of sensitivity experiments strongly corroborate the observed WNPTC-AMM linkage and underlying physical mechanisms.

  18. Biomass enables the transition to a carbon-negative power system across western North America

    Science.gov (United States)

    Sanchez, Daniel L.; Nelson, James H.; Johnston, Josiah; Mileva, Ana; Kammen, Daniel M.

    2015-03-01

    Sustainable biomass can play a transformative role in the transition to a decarbonized economy, with potential applications in electricity, heat, chemicals and transportation fuels. Deploying bioenergy with carbon capture and sequestration (BECCS) results in a net reduction in atmospheric carbon. BECCS may be one of the few cost-effective carbon-negative opportunities available should anthropogenic climate change be worse than anticipated or emissions reductions in other sectors prove particularly difficult. Previous work, primarily using integrated assessment models, has identified the critical role of BECCS in long-term (pre- or post-2100 time frames) climate change mitigation, but has not investigated the role of BECCS in power systems in detail, or in aggressive time frames, even though commercial-scale facilities are starting to be deployed in the transportation sector. Here, we explore the economic and deployment implications for BECCS in the electricity system of western North America under aggressive (pre-2050) time frames and carbon emissions limitations, with rich technology representation and physical constraints. We show that BECCS, combined with aggressive renewable deployment and fossil-fuel emission reductions, can enable a carbon-negative power system in western North America by 2050 with up to 145% emissions reduction from 1990 levels. In most scenarios, the offsets produced by BECCS are found to be more valuable to the power system than the electricity it provides. Advanced biomass power generation employs similar system design to advanced coal technology, enabling a transition strategy to low-carbon energy.

  19. Segregation of herring larvae from inshore and offshore spawning grounds in the north-western North Sea — Implications for stock structure

    Science.gov (United States)

    Heath, M.

    Herring larvae hatching from spawning sites around the Scottish coast are dispersed by water currents during the weeks following hatching. Hydrographic data, observations on the distribution of caesium-137 and measurements of current velocities by moored meters and drifting buoys, suggest that larvae from offshore spawning sites around the north of Scotland should be more rapidly dispersed than those hatching in inshore areas. This has been confirmed by direct observations on the advection of herring larvae in different regions of the north western North Sea. The conclusion is that larvae hatching in inshore areas, especially in the Moray Firth, are most likely to contribute to nearby juvenile populations, whereas larvae from offshore spawning sites should be widely dispersed over the North Sea. Tagging and parasitology investigations have shown that adult herring spawning in the north-western North Sea have been widely dispersed in the North Sea and adjacent waters as juveniles (six months — one and a half years old). However, a high proportion of adult fish caught at inshore spawning sites and in the Moray Firth were found to have been recruited from more local areas. Taken together with the observations on larval drift, these observations suggest that the stock structure of herring in the northern North Sea may in part be a consequence of the physical oceanography of the area.

  20. Patagonian Glacier Advances in Concert with those in Western North America

    Science.gov (United States)

    Maurer, M. K.; Menounos, B.; Clague, J. J.; osborn, G.

    2012-12-01

    The question of whether Holocene glacier advances in the Northern and Southern hemispheres are synchronous remains open. Here we report on the evidence for late Holocene advances at Stoppani Glacier (54.78° S, 68.98° W), 50 km west of Ushuaia, Argentina, and compare this record to glacier fluctuations in western North America. The glacier is an outlet glacier of the Darwin Cordillera icefield, has an area of 92 km2 and descends to 80 m asl. Wood mats containing stumps in growth position are separated by units of till in a 100-m-high section through the northeast lateral moraine. Radiocarbon ages on the wood mats and stumps decrease up-section, demonstrating that Stoppani Glacier advanced successively farther over the past 3800 years. The earliest of the advances is recorded by a till overlying peat containing wood that returned a calibrated radiocarbon age of 3.83-3.64 ka (kilo calendar years BP). This advance coincides with a well documented glacier advance in western Canada, the so-called '4.2 ka event' [4.2-3.8 ka]. Stoppani Glacier further thickened and overran stumps in growth position at 3.16-2.95 and at 2.86-2.76 ka; both of these events are contemporaneous with widespread advances of alpine glaciers in British Columbia and Alberta. A fourth advance of Stoppani Glacier at about 2.30-2.01 ka coincides with advances of Deming Glacier on Mount Baker, Washington, USA [2.35-2.15 ka], and several glaciers in the Coast Mountains of British Columbia, Canada. The final advance of Stoppani Glacier began about 0.29 ka when the glacier thickened, overran a vegetated surface, and deposited till that forms the crest of the moraine. This advance coincides with the maximum, classical, Little Ice Age advance of nearly all glaciers in western North America. Collectively, our data indicate that Stoppani Glacier advanced in step with glaciers in western North America during the late Holocene. The most parsimonious explanation is that century-scale climate forcing

  1. Water vapour accumulation mechanisms in the Western Mediterranean Basin and the development of European extreme rainfalls

    Directory of Open Access Journals (Sweden)

    E. Sáez de Cámara

    2011-01-01

    Full Text Available This paper examines the role of a recently described warm season circulation at the middle troposphere of northern Africa and that of the recirculation-accumulation mode of the Western Mediterranean Basin (WMB in the initiation of rainfall episodes in central and eastern Europe. Both of these atmospheric mechanisms can accumulate not only soil dust and pollutants for several days but also water vapour by evaporation both over the subtropical Atlantic and the western and central Mediterranean. Accumulation layers are vented off into the surrounding area after the irruption of perturbations. In particular, this work explores the exportation of water vapour under perturbed conditions associated with the passage of ‘Vb’ cyclones. The exceptional rainfall experienced over large areas of central Europe (Elbe/Danube floods during August 11-13, 2002 is exposed as a case study. The procedure to simulate the mechanisms involves a combination of the Regional Atmospheric Modelling System and HYbrid PArticle Concentration and Transport modelling systems. MODIS water vapour products, radio-soundings, wind profiler radars and surface-satellite precipitation data are used to verify the simulation outputs. Our results show that most of the precipitation occurring in the target area during the initiation and deepening of the episode was very likely originated in an air mass exported from the WMB. After our tracking experiment, that air mass, with an initial Atlantic origin, entered the WMB and circulated during 4 days (August 6-9 within the marine boundary layer and the coastal range of mountains of the WMB, accumulating vapour. Then, most of it was transported on August 10, after the irruption of the 'Vb' cyclone Ilse, through the Italian Peninsula and the Adriatic Sea, across the Western Balkans into the target area. The transported vapour together with evaporation en route initiated the rainfall episode.

  2. Subsidence History of the Eastern Depression in the North Yellow Sea Basin

    Institute of Scientific and Technical Information of China (English)

    CAO Dai-yong; WANG Xin-guo; ZHAN Wen-feng; LI Wen-yong

    2007-01-01

    Using a back-stripping method, our paper simulated the subsidence history of the eastern depression in the North Yellow Sea Basin. The subsidence history curve pattern and the subsidence chorisogram during every subsiding period were exposed. Combining with the regional geologic background and the distribution features of the subsiding centers in every period, a contrasting study of the pattern and the classical subsidence history curves shows the subsidence history is made up of Mesozoic (J3-K1) and Cenozoic (E2-Q) subsiding cycles. The two subsiding cycles are separated by the late Cretaceous and Paleocene (K2-E1) uplift denudation. Both subsiding cycles have the characteristics of an extension basin. The rapid subsidence during the late Jurassic and Eocene is equivalent to the initial subsiding phases in both cycles.. The slow subsidence of both, the early Cretaceous and Neogene, can be regarded as thermal subsidence phases.

  3. Western Gas Sands Project. Quarterly basin activities report, October 1-December 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    This report is a summation of three months drilling and testing activitie in the four primary study areas of the WGSP: Greater Green River Basin, Northern Great Plains Province, Piceance Basin, and Uinta Basin.

  4. Seismic and Gravity Investigations of the Western Espanola Basin, Rio Grande Rift, New Mexico

    Science.gov (United States)

    Braile, L. W.; Coldren, B. G.; Baca, A.; Fontana, J.; Olheiser, M.; Ziff, M.; Keske, A.; Rhode, A.; Martin-Short, R.; Allen, W.; Denton, K. M.; Harper, C.; Baldridge, W.; Biehler, S.; Ferguson, J. F.; McPhee, D.; Snelson, C. M.

    2013-12-01

    The SAGE (Summer of Applied Geophysical Experience) program collected new seismic, gravity, electromagnetic and down-hole temperature data in 2013 in the western Espanola basin of the Rio Grande rift area of northern New Mexico. The location, about 25 km NW of Santa Fe, has been identified as a potential geothermal resources area based on relatively high temperature gradients in drill holes. The SAGE 2013 data collection was part of an integrated geophysical study of the area initiated in 2011. Seismic data consisted of a 4.8 km W to E profile (120 three-component stations in four overlapping deployments, 20 m station spacing, using a Vibroseis source - 20 m spacing for reflection VPs; 800 m spacing for refraction VPs) with both refraction and CMP reflection coverage. About 55,000 seismograms were recorded. The surface conditions (dry unconsolidated sediments) increased surface wave energy and limited the signal-to-noise level of the refraction and reflection arrivals. Utilizing longer source-receiver offsets improved the shot-gather record sections by emphasizing wider angle reflections which are very strong and coherent. The refraction data were modeled with first arrival travel time methods. The reflection data were processed to produce a CMP stacked record section. Strong reflectors from basin-filling sedimentary rocks (mostly Tertiary in age) are visible above reflections from a thin section of Paleozoic rocks and the basement. The lower reflections have an apparent dip to the west of about 12 degrees. Eighty-one new gravity measurements (detailed data at 200 m spacing along the seismic profile, and regional stations) were collected and combined with existing regional data for modeling. Interpretation of the seismic and gravity data was aided by refraction velocities, the existence of a nearby regional seismic reflection profile from industry, and lithologies and well-logs from a deep well. The sedimentary basin interpreted from the seismic and gravity data

  5. Shallow ground-water quality beneath cropland in the Red River of the North Basin, Minnesota and North Dakota, 1993-95

    Science.gov (United States)

    Cowdery, Timothy K.

    1997-01-01

    During 1993-95, the agriculture on two sandy, surficial aquifers in the Red River of the North Basin affected the quality of shallow ground water in each aquifer differently. The Sheyenne Delta aquifer, in the western part of the basin, had land-use, hydrogeological, and rainfall characteristics that allowed few agricultural chemicals to reach or remain in the shallow ground water. The Otter Tail outwash aquifer, in the eastern part of the basin, had characteristics that caused significant amounts of nutrients and pesticides to reach and remain in the shallow ground water. Shallow ground water from both aquifers is dominated by calcium, magnesium, and bicarbonate ions. During the respective sampling periods, water from the Sheyenne Delta aquifer was mostly anoxic and water from the Otter Tail outwash aquifer had a median dissolved oxygen concentration of 3.6 mg/L (milligrams per liter). The median nitrate concentration was 0.03 mg/L as nitrogen (mg/L-N) in shallow ground water from the Sheyenne Delta aquifer and 6.1 mg/L-N in that from the Otter Tail outwash aquifer. Of 18 herbicides and 4 insecticides commonly used in the aquifer areas and for which analyses were done, 5 herbicides and 1 herbicide metabolite were detected in the shallow ground water from the Sheyenne Delta aquifer and 8 herbicides and 2 metabolites were detected in that from the Otter Tail outwash aquifer. The total herbicide concentration median was less than the detection limit in shallow ground water from the Sheyenne Delta aquifer and 0.023 μg/L (micorgrams per liter) in that from the Otter Tail outwash aquifer. Triazine herbicides were the most commonly detected herbicides and were detected at the highest concentrations in the shallow ground water from both study areas. One sample from the Sheyenne Delta aquifer contained a high concentration of picloram. Agricultural chemicals in both aquifers were stratified vertically and their concentration correlated inversely with ground-water age. The

  6. Size Scaling in Western North Atlantic Loggerhead Turtles Permits Extrapolation between Regions, but Not Life Stages.

    Directory of Open Access Journals (Sweden)

    Nina Marn

    Full Text Available Sea turtles face threats globally and are protected by national and international laws. Allometry and scaling models greatly aid sea turtle conservation and research, and help to better understand the biology of sea turtles. Scaling, however, may differ between regions and/or life stages. We analyze differences between (i two different regional subsets and (ii three different life stage subsets of the western North Atlantic loggerhead turtles by comparing the relative growth of body width and depth in relation to body length, and discuss the implications.Results suggest that the differences between scaling relationships of different regional subsets are negligible, and models fitted on data from one region of the western North Atlantic can safely be used on data for the same life stage from another North Atlantic region. On the other hand, using models fitted on data for one life stage to describe other life stages is not recommended if accuracy is of paramount importance. In particular, young loggerhead turtles that have not recruited to neritic habitats should be studied and modeled separately whenever practical, while neritic juveniles and adults can be modeled together as one group. Even though morphometric scaling varies among life stages, a common model for all life stages can be used as a general description of scaling, and assuming isometric growth as a simplification is justified. In addition to linear models traditionally used for scaling on log-log axes, we test the performance of a saturating (curvilinear model. The saturating model is statistically preferred in some cases, but the accuracy gained by the saturating model is marginal.

  7. New predictors and a new prediction model for the typhoon frequency over western North Pacific

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, the impacts of the atmospheric circulation during boreal winter-spring on the western North Pacific (WNP) typhoon frequency (WNPTF) are studied. Several new factors in winter-spring influencing the typhoon frequency were identified, including the sea ice cover in the North Pacific and the North Pacific oscillation. Based on these results, the multi-linear regression was applied to establishing a new forecast model for the typhoon frequency by using the datasets of 1965―1999. The forecast model shows a high correlation coefficient (0.79) between the model simulated and the actual typhoon frequencies in the period of 1965―1999. The forecast model also exhibits reasonable hindcasts for the typhoon frequencies for the years 2000―2006. Therefore, this work demonstrates that the new predictors are significant for the prediction of the interannual variability of the WNPTF, which could be potentially used in the operational seasonal forecast of the typhoon frequency in the WNP to get a more physically based operational prediction model and higher forecast skill.

  8. Lost in Translation? Pussy Riot Solidary Activism and the danger of perpetuating North/Western Hegemonies

    Directory of Open Access Journals (Sweden)

    Katharina Wiedlack

    2014-12-01

    Full Text Available This article critically discusses solidarity actions in support of Pussy Riot within the global North/West, arguing that most solidarity projects within popular culture as well as within the queer-feminist counterculture are based on a lopsided interpretation of Pussy Riot as Russian version of Riot Grrrl feminists. This one-dimensional interpretation of the performance art group as Riot Grrrl-identities further leads to labelling their performance at the Christ the Saviour Cathedral as anti-religious. Within this framework the group’s negotiation of Orthodox religion within their song lyrics, performances as well as statements is ignored, supporting the binary construction of The North/West as progressive – tolerant and secular – and Russia as backward – dogmatic and fundamentalist religious. We attempt to complicate the view on Pussy Riot’s performances and reread them within the Russian context, highlighting several political statements that got lost in North/Western translations. The focus of the analysis concentrates on the ‘Punk Prayer, its mimicry of religious language and references to the leadership of the Russian Orthodox Church as well as the local public critical discourses.

  9. Statistical Aspects of Tropical Cyclone Activity in the North Atlantic Basin, 1945-2010

    Science.gov (United States)

    Wilson, Robert M.

    2012-01-01

    Examined are statistical aspects of the 715 tropical cyclones that formed in the North Atlantic basin during the interval 1945-2010. These 715 tropical cyclones include 306 storms that attained only tropical storm strength, 409 hurricanes, 179 major or intense hurricanes, and 108 storms that struck the US coastline as hurricanes. Comparisons made using 10-year moving average (10-yma) values between tropical cyclone parametric values and surface air and ENSO-related parametric values indicate strong correlations to exist, in particular, against the Armagh Observatory (Northern Ireland) surface air temperature, the Atlantic Multi-decadal Oscillation (AMO) index, the Atlantic Meridional Mode (AMM) index, and the North Atlantic Oscillation (NAO) index, in addition to the Oceanic Ni o index (ONI) and Quasi-Biennial Oscillation (QBO) indices. Also examined are the decadal variations of the tropical cyclone parametric values and a look ahead towards the 2012 hurricane season and beyond.

  10. Meso-Cenozoic Tectono-Thermal Evolution History in Bohai Bay Basin, North China

    Institute of Scientific and Technical Information of China (English)

    Yinhui Zuo; Nansheng Qiu; Jiawei Li; Qingqing Hao; Xiongqi Pang; Zhongying Zhao; Qi Zhu

    2015-01-01

    The thermal history of sedimentary basins is a key factor for hydrocarbon accumula-tion and resource assessment, and is critical in the exploration of lithospheric tectono-thermal evo-lution. In this paper, the Cenozoic thermal histories of nearly 200 wells and the Mesozoic thermal histories of 15 wells are modeled based on the vitrinite reflectance and apatite fission track data in Bohai Bay Basin, North China. The results show that the basin experienced Early Cretaceous and Paleogene heat flow peaks, which reveals two strong rift tectonic movements that occurred in the Cretaceous and the Paleogene in the basin, respectively. The thermal evolution history in Bohai Bay Basin can be divided into five stages including (1) the low and stable heat flow stage from the Trias-sic to the Jurassic, with the heat flow of 53 to 58 mW/m2;(2) the first heat flow peak from the Early Cretaceous to the middle of the Late Cretaceous, with a maximum heat flow of 81 to 87 mW/m2;(3) the first post-rift thermal subsidence stage from the middle of the Late Cretaceous to the Paleocene, with the heat flow of 65 to 74 mW/m2 at the end of the Cretaceous; (4) the second heat flow peak from the Eocene to the Oligocene, with a maximum heat flow of 81 to 88 mW/m2;and (5) the second thermal subsidence stage from the Neogene to present, with an average heat flow of 64 mW/m2.

  11. Hydrogeochemical comparison and effects of overlapping redox zones on groundwater arsenic near the Western (Bhagirathi sub-basin, India) and Eastern (Meghna sub-basin, Bangladesh) margins of the Bengal Basin.

    Science.gov (United States)

    Mukherjee, Abhijit; von Brömssen, Mattias; Scanlon, Bridget R; Bhattacharya, Prosun; Fryar, Alan E; Hasan, Md Aziz; Ahmed, Kazi Matin; Chatterjee, Debashis; Jacks, Gunnar; Sracek, Ondra

    2008-07-29

    Although arsenic (As) contamination of groundwater in the Bengal Basin has received wide attention over the past decade, comparative studies of hydrogeochemistry in geologically different sub-basins within the basin have been lacking. Groundwater samples were collected from sub-basins in the western margin (River Bhagirathi sub-basin, Nadia, India; 90 samples) and eastern margin (River Meghna sub-basin; Brahmanbaria, Bangladesh; 35 samples) of the Bengal Basin. Groundwater in the western site (Nadia) has mostly Ca-HCO(3) water while that in the eastern site (Brahmanbaria) is much more variable consisting of at least six different facies. The two sites show differences in major and minor solute trends indicating varying pathways of hydrogeochemical evolution However, both sites have similar reducing, postoxic environments (p(e): +5 to -2) with high concentrations of dissolved organic carbon, indicating dominantly metal-reducing processes and similarity in As mobilization mechanism. The trends of various redox-sensitive solutes (e.g. As, CH(4), Fe, Mn, NO(3)(-), NH(4)(+), SO(4)(2-)) indicate overlapping redox zones, leading to partial redox equilibrium conditions where As, once liberated from source minerals, would tend to remain in solution because of the complex interplay among the electron acceptors. PMID:18164513

  12. Empirical models to predict the volumes of debris flows generated by recently burned basins in the western U.S.

    Science.gov (United States)

    Gartner, J.E.; Cannon, S.H.; Santi, P.M.; deWolfe, V.G.

    2008-01-01

    Recently burned basins frequently produce debris flows in response to moderate-to-severe rainfall. Post-fire hazard assessments of debris flows are most useful when they predict the volume of material that may flow out of a burned basin. This study develops a set of empirically-based models that predict potential volumes of wildfire-related debris flows in different regions and geologic settings. The models were developed using data from 53 recently burned basins in Colorado, Utah and California. The volumes of debris flows in these basins were determined by either measuring the volume of material eroded from the channels, or by estimating the amount of material removed from debris retention basins. For each basin, independent variables thought to affect the volume of the debris flow were determined. These variables include measures of basin morphology, basin areas burned at different severities, soil material properties, rock type, and rainfall amounts and intensities for storms triggering debris flows. Using these data, multiple regression analyses were used to create separate predictive models for volumes of debris flows generated by burned basins in six separate regions or settings, including the western U.S., southern California, the Rocky Mountain region, and basins underlain by sedimentary, metamorphic and granitic rocks. An evaluation of these models indicated that the best model (the Western U.S. model) explains 83% of the variability in the volumes of the debris flows, and includes variables that describe the basin area with slopes greater than or equal to 30%, the basin area burned at moderate and high severity, and total storm rainfall. This model was independently validated by comparing volumes of debris flows reported in the literature, to volumes estimated using the model. Eighty-seven percent of the reported volumes were within two residual standard errors of the volumes predicted using the model. This model is an improvement over previous models in

  13. Gas hydrate distribution and hydrocarbon maturation north of the Knipovich Ridge, western Svalbard margin

    Science.gov (United States)

    Dumke, Ines; Burwicz, Ewa B.; Berndt, Christian; Klaeschen, Dirk; Feseker, Tomas; Geissler, Wolfram H.; Sarkar, Sudipta

    2016-03-01

    A bottom-simulating reflector (BSR) occurs west of Svalbard in water depths exceeding 600 m, indicating that gas hydrate occurrence in marine sediments is more widespread in this region than anywhere else on the eastern North Atlantic margin. Regional BSR mapping shows the presence of hydrate and free gas in several areas, with the largest area located north of the Knipovich Ridge, a slow spreading ridge segment of the Mid Atlantic Ridge system. Here heat flow is high (up to 330 mW m-2), increasing toward the ridge axis. The coinciding maxima in across-margin BSR width and heat flow suggest that the Knipovich Ridge influenced methane generation in this area. This is supported by recent finds of thermogenic methane at cold seeps north of the ridge termination. To evaluate the source rock potential on the western Svalbard margin, we applied 1-D petroleum system modeling at three sites. The modeling shows that temperature and burial conditions near the ridge were sufficient to produce hydrocarbons. The bulk petroleum mass produced since the Eocene is at least 5 kt and could be as high as ~0.2 Mt. Most likely, source rocks are Miocene organic-rich sediments and a potential Eocene source rock that may exist in the area if early rifting created sufficiently deep depocenters. Thermogenic methane production could thus explain the more widespread presence of gas hydrates north of the Knipovich Ridge. The presence of microbial methane on the upper continental slope and shelf indicates that the origin of methane on the Svalbard margin varies spatially.

  14. A new centennial index to study the Western North Pacific Monsoon decadal variability

    Science.gov (United States)

    Vega, Inmaculada; Gómez-Delgado, F. de Paula; Gallego, David; Ribera, Pedro; Peña-Ortiz, Cristina; García-Herrera, Ricardo

    2016-04-01

    The concept of the Western North Pacific Summer Monsoon (WNPSM) appeared for the first time in 1987. It is, unlike the Indian Summer Monsoon (ISM) and the East Asian summer monsoon (EASM), an oceanic monsoon mostly driven by the meridional gradient of sea surface temperature. Its circulation is characterized by a northwest-southeast oriented monsoon trough with intense precipitation and low-level southwesterlies and upper-tropospheric easterlies in the region [100°-130° E, 5°-15°N]. Up to now, the primary index to characterize the WNPSM has been the Western North Pacific Monsoon Index (WNPMI) which covers the 1949-2013 period. The original WNPMI was defined as the difference of 850-hPa westerlies between two regions: D1 [5°-15°N, 100°-130°E] and D2 [20°-30°N, 110°-140°E]. Both domains are included in the main historical ship routes circumnavigating Asia for hundreds of years. Many of the logbooks of these ships have been preserved in historical archives and they usually contain daily observations of wind force and direction. Therefore, it has been possible to compute a new index of instrumental character, which reconstructs the WNPSM back to the middle of the 19th Century, by using solely historical wind direction records preserved in logbooks. We define the monthly Western North Pacific Directional Index (WNPDI) as the sum of the persistence of the low-level westerly winds in D1 and easterly winds in D2. The advantages of this new index are its nature (instrumental) and its length (1849-2013), which is 100 years longer than the WNPMI (which was based on reanalysis data). Our WNPDI shows a high correlation (r=+0.87, pPhilippines or the west coast of Myanmar where the changes in precipitation between well developed and weak monsoons can reach up to 400 mm. The relationships between the WNPDI and global climatic patterns such as the PDO, the ENSO or El Niño Modoki are extremely complicated and our results suggest that the influence of these patterns is

  15. Famennian mud-mounds in the proximal fore-reef slope, Canning Basin, Western Australia

    Science.gov (United States)

    Webb, Gregory E.

    2001-12-01

    Famennian (Late Devonian) carbonate buildups and, in particular, mud-mounds, are poorly known, in general, and few have been documented in detail. Relatively small Famennian mud-mounds occur in proximal fore-reef slope settings in the Canning Basin, Western Australia. The Famennian platform margin facies passes from typical shoaling carbonate facies in the back reef, through massive, calcimicrobial, cement-rich reef-margin facies, to relatively steeply dipping (20-30°), well-bedded fore-reef slope facies containing shelf-derived, winnowed grainy sediments and extremely coarse reef-block debris. Isolated or coalescing mounds occur in the proximal slope, immediately adjacent to and, in some cases, possibly grading into the margin facies. Mounds are elongate perpendicular to the margin and some had synoptic relief greater than 2 m. Mounds are lithologically variable and consist of varying proportions of micrite, multiple generations of marine cement, abundant Rothpletzella, Renalcis, poorly preserved sparry microbial crusts and sporadically distributed laminar stromatoporoids. Surrounding grainy slope facies abut and slope off of mound flanks. Mound facies are very similar to nearby reef-margin facies, with the exceptions that stromatoporoids have not been observed in margin facies and solenoporoid algae, which occur in the margin, have not been observed in the mounds. Stromatolites are conspicuously absent from both facies. Mound facies appear to be more closely related to Frasnian and Famennian calcimicrobe cement-dominated reef-margin facies than to Famennian deep-water stromatolite-sponge-mound facies, such as those that occur elsewhere in the Canning Basin. The observed Canning Famennian reef and mound frameworks were constructed by communities that appear to be very similar to earlier Frasnian communities, despite the Frasnian-Famennian extinction event, and provide good examples of microbial reef framework construction in a high energy setting.

  16. Heat transfer and fluid flow modelling in supra-detachment basins: a case study of the Devonian basins of western Norway

    Science.gov (United States)

    Souche, A.; Dabrowski, M.; Andersen, T. B.; Medvedev, S.

    2012-04-01

    The Devonian basins of western Norway are supra-detachment basins located above a large crustal-scale detachment system, so-called the Nordfjord Sogn Detachment Zone. These basins are characterised by a thick succession (>10km) of siliciclastic sediments ranging in size from coarse conglomerates to fine grain sandstones and organized into narrow half-graben systems. Their architecture and geometry is closely controlled by the development of the coeval (i.e. Early to Middle Devonian) detachment acting as a normal fault/shear zone beneath the basins. The exhumation of rocks within the footwall of the detachment was subsequently followed by an increase of the geothermal gradient at the base of the sedimentary successions. Shear heating resulting from the intense rock deformation within the shear zone also played a role in increasing the temperature at the base of the basins. These two significant processes might have in turn contributed to the fluid mobility in the basins. In this study, we explore the feasibility of porous convection to occur spontaneously in sedimentary basins due to a regional increase of the geothermal gradient. Such process can be approximated by Darcy flow through porous media where the fluid density in the system might introduce a buoyancy-driven instability between lighter hot fluids at the base and denser cold fluids at the top of the basin. In geological systems porous flow might be inhibited by the closing of pores with depth, which leads to a reduced permeability and a limited amount of heat carrying fluids. Also, geological heterogeneities inherited from the layered structure of the sedimentary strata introduce large variations in the rock transport properties. We address these problems numerically by modelling heat and mass transport in porous media assuming quasi-incompressible Darcy flow. The fluid (water) density, viscosity, and specific heat are computed from the pore fluid pressure and the temperature. We investigate the onset of

  17. From hyper-extended rifts to orogens: the example of the Mauléon rift basin in the Western Pyrenees (SW France)

    Science.gov (United States)

    Masini, E.; Manatschal, G.; Tugend, J.

    2011-12-01

    An integral part of plate tectonic theory is that the fate of rifted margins is to be accreted into mountain belts. Thus, rift-related inheritance is an essential parameter controlling the evolution and architecture of collisional orogens. Although this link is well accepted, rift inheritance is often ignored. The Pyrenees, located along the Iberian and European plate boundary, can be considered as one of the best places to study the reactivation of former rift structures. In this orogen the Late Cretaceous and Tertiary convergence overprints a Late Jurassic to Lower Cretaceous complex intracontinental rift system related to the opening of the North Atlantic. During the rifting, several strongly subsiding basins developed in the axis of the Pyrenees showing evidence of extreme crustal extension and even locale mantle exhumation to the seafloor. Although the exact age and kinematics of rifting is still debated, these structures have an important impact in the subsequent orogenic overprint. In our presentation we discuss the example of the Mauléon basin, which escaped from the most pervasive deformations because of its specific location at the interface between the western termination of the chain and the Bay of Biscay oceanic realm. Detailed mapping combined with seismic reflection, gravity data and industry wells enabled to determine the 3D rift architecture of the Mauléon basin. Two major diachronous detachment systems can be mapped and followed through space. The Southern Mauléon Detachment (SMD) develops first, starts to thin the crust and floors the Southern Mauléon sub-Basin (SMB). The second, the Northern Mauléon Detachment (SMD) is younger and controls the final crustal thinning and mantle exhumation to the north. Both constitute the whole Mauléon basin. Like at the scale of the overall Pyrenees, the reactivation of the Mauléon Basin increases progressively from west to east, which enables to document the progressive reactivation of an aborted hyper

  18. Influences of North Atlantic climate variability on low-flows in the Connecticut River Basin

    Science.gov (United States)

    Steinschneider, Scott; Brown, Casey

    2011-10-01

    SummaryConnections between summertime, ecologically relevant low-flow indicators and both winter and spring climate phenomena are explored for the Connecticut River Basin, with an emphasis on assessing forecast potential. Low-flow streamflow statistics deemed important for ecological health, including minimum 1-day mean flows, minimum 7-day mean flows, and monthly streamflow averages from June to September, are derived from 61 years of continuous, daily streamflow data at 15 United States Geological Survey streamflow gauging stations across the basin. Relationships between the ecological flow indicators with leading sea-surface temperature and sea-level pressure are investigated using correlation and composite analysis. Results suggest lagged relationships of up to 5 months between summer streamflow and the wintertime North Atlantic Oscillation, springtime east coast pressure trough, and springtime North Atlantic Tripole. These climate states have been linked to shifts between zonal and meridonal airflow as well as sea-surface temperature anomalies off the coast of the eastern US, both of which have implications for the movement of moisture systems over the study region. This study suggests that residual influences on airflow and sea-surface temperature persist into the summer following these earlier climate states, influencing low-flow hydrology in the region. As eco-hydrologic flow targets often conflict with other stakeholder objectives within a watershed, reservoir operators may utilize such lagged teleconnection patterns to predict annual low-flow characteristics in the region and help negotiate tradeoffs between traditional water management objectives and those emphasizing ecological conservation.

  19. Progress and outlook of uranium exploration in meso-cenozoic basins in north China

    International Nuclear Information System (INIS)

    Through the efforts in last decades on the research of geology setting and regional assessment for uranium exploration in the Meso-Cenozoic basins in North China, rich accomplishment have been gotten in metallogenic theory, temporal and spatial distribution pattern, zone division, Classification, mineralization of different type, ore-controlling factors, metallogenic model, principle of valuation and prognostication, exploration criteria and great breakthrough in the prospecting of key areas. However, the extensive territory make the effort limited only to some region, the exploration level is fairly lower in the whole country, and there is wide space for uranium exploration. The further exploration should be basically guided by 'highlighting the exploration of key areas, strengthening the evaluation of regional potential and accelerating the implementation of new reserve bases' and persisted in principle of 'deployment with different level and execution according to region' and oriented with different types of deposit by 'wholly evaluation and systematic exploration'. By deploying the new effort frame in large base exploration, regional evaluation and solving the important geological and geophysical problem, we can put forward the uranium exploration in Meso-Cenozoic basins in North China. (author)

  20. The influence of chilling requirement on the southern distribution limit of exotic Russian olive (Elaeagnus angustifolia) in western North America

    Science.gov (United States)

    Guilbault, Kimberly R.

    2011-01-01

    Russian olive (Elaeagnus angustifolia L.), a Eurasian tree, is now a dominant species along rivers in western North America. The southern boundary of Russian olive distribution in western North America runs through southern California, Arizona, New Mexico and Texas. I related the distributional pattern of Russian olive to temperature regime and investigated potential temperature-dependent mechanisms that might explain this distributional limit. Specifically, I investigated whether lack of cold temperatures at the southern limit may prevent the accumulation of sufficient chilling and inhibit dormancy loss of seeds and buds, potentially constraining Russian olive's southern distribution boundary.

  1. Influence of climatic warming in the Southem and Northem Hemisphere on the tropical cyclone over the western North Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    TIAN Rong-xiang; WENG Huan-xin

    2006-01-01

    Based on analyzing the surface air temperature series in the Southern and Northern Hemisphere and the tropical cyclone (TC) over the western North Pacific Ocean, the relationships between climatic warming and the frequency and intensity of tropical cyclone are investigated. The results showed that with the climatic warming in both hemispheres, the frequency of the tropical cyclone over the western North Pacific Ocean reduces and its intensity weakens simultaneously. A possible explanation might be that the cold air invasion from the Southern Hemisphere weakens due to global warming.

  2. Hydrocarbon Source Rocks in the Deep River and Dan River Triassic Basins, North Carolina

    Science.gov (United States)

    Reid, Jeffrey C.; Milici, Robert C.

    2008-01-01

    This report presents an interpretation of the hydrocarbon source rock potential of the Triassic sedimentary rocks of the Deep River and Dan River basins, North Carolina, based on previously unpublished organic geochemistry data. The organic geochemical data, 87 samples from 28 drill holes, are from the Sanford sub-basin (Cumnock Formation) of the Deep River basin, and from the Dan River basin (Cow Branch Formation). The available organic geochemical data are biased, however, because many of the samples collected for analyses by industry were from drill holes that contained intrusive diabase dikes, sills, and sheets of early Mesozoic age. These intrusive rocks heated and metamorphosed the surrounding sediments and organic matter in the black shale and coal bed source rocks and, thus, masked the source rock potential that they would have had in an unaltered state. In places, heat from the intrusives generated over-mature vitrinite reflectance (%Ro) profiles and metamorphosed the coals to semi-anthracite, anthracite, and coke. The maximum burial depth of these coal beds is unknown, and depth of burial may also have contributed to elevated thermal maturation profiles. The organic geochemistry data show that potential source rocks exist in the Sanford sub-basin and Dan River basin and that the sediments are gas prone rather than oil prone, although both types of hydrocarbons were generated. Total organic carbon (TOC) data for 56 of the samples are greater than the conservative 1.4% TOC threshold necessary for hydrocarbon expulsion. Both the Cow Branch Formation (Dan River basin) and the Cumnock Formation (Deep River basin, Sanford sub-basin) contain potential source rocks for oil, but they are more likely to have yielded natural gas. The organic material in these formations was derived primarily from terrestrial Type III woody (coaly) material and secondarily from lacustrine Type I (algal) material. Both the thermal alteration index (TAI) and vitrinite reflectance data

  3. Heterogeneous impact of traveling to Western countries on gender norms in Middle East and North Africa countries

    OpenAIRE

    Atamanov, Aziz

    2015-01-01

    Social gender norms shape individuals’ opportunities and actions. Traditional and gender biased norms can contribute to persistent gender disparities. However, counter-stereotypical images can shift an expected behavior for men and women. This paper investigates if traveling to Western countries relaxes gender norms in the Middle East and North Africa region using the Arab Barometer data. Preliminary empirical findings suggest that international travel to Western countries is associated with ...

  4. A new structural interpretation relating NW Libya to the Hun Graben, western Sirt Basin based on a new paleostress inversion

    Science.gov (United States)

    Abdunaser, K. M.; McCaffrey, K. J. W.

    2015-12-01

    The present study is based on fault-slip data (striated fault planes with known sense of slip) measured in outcrops in two structural domains located along the Hun Graben, western Sirt Basin (150 fault-slip data) and the Jifarah Basin and Nafusah Uplift, northwest Libya (200 fault-slip data). Pre-existing field data collected in two previous studies were reprocessed using standard inversion methods in MyFaultTM(v. 1.03) stereonet software, produced by Pangaea Scientific Ltd.

  5. Intensified impact of tropical Atlantic SST on the western North Pacific summer climate under a weakened Atlantic thermohaline circulation

    OpenAIRE

    Chen, Wei; Lee, June-Yi; Lu, Riyu; Dong, Buwen; Ha, Kyung-Ja

    2015-01-01

    The tropical North Atlantic (TNA) sea surface temperature (SST) has been identified as one of regulators on the boreal summer climate over the western North Pacific (WNP), in addition to SSTs in the tropical Pacific and Indian Oceans. The major physical process proposed is that the TNA warming induces a pair of cyclonic circulation anomaly over the eastern Pacific and negative precipitation anomalies over the eastern to central tropical Pacific, which in turn lead to an anticyclonic circulati...

  6. The Coupled Model Predictability of the Western North Pacific Summer Monsoon with Different Leading Times

    Institute of Scientific and Technical Information of China (English)

    LU Ri-Yu; LI Chao-Fan; Se-Hwan YANG; Buwen DONG

    2012-01-01

    Leading time length is an important issue for modeling seasonal forecasts. In this study, a comparison of the interannual predictability of the Western North Pacific (WNP) summer monsoon between different leading months was performed by using one-, four-, and sevenmonth lead retrospective forecasts (hindcasts) of four coupled models from Ensembles-Based Predictions of Climate Changes and Their Impacts (ENSEMBLES) for the period of 1960 2005. It is found that the WNP summer anomalies, including lower-tropospheric circulation and precipitation anomalies, can be well predicted for all these leading months. The accuracy of the four-month lead prediction is only slightly weaker than that of the one-month lead prediction, although the skill decreases with the increase of leading months.

  7. North Western Spain hot springs are a source of lipolytic enzyme-producing thermophilic microorganisms.

    Science.gov (United States)

    Deive, Francisco J; Alvarez, María S; Sanromán, M Angeles; Longo, Maria A

    2013-02-01

    Several hot springs in Galicia (North Western Spain) have been investigated as potential sources of lipolytic enzyme-producing thermophilic microorganisms. After isolating 12 esterase producing strains, 9 of them were assured to be true lipase producers, and consequently grown in submerged cultures, obtaining high extracellular activities by two of them. Furthermore, a preliminary partial characterization of the crude lipase, obtained by ultrafiltration of the cell-free culture supernatant, was carried out at several pH and temperature values. It is outstanding that several enzymes turned out to be multiextremozymes, since they had their optimum temperature and pH at typical values from thermoalkalophiles. The thermal stability in aqueous solution of the crude enzymes was also assayed, and the influence of some potential enzyme stabilizing compounds was tested. Finally, the viability of the selected microorganisms has been demonstrated at bioreactor scale.

  8. Enhanced or Weakened Western North Pacific Subtropical High under Global Warming?

    Science.gov (United States)

    He, Chao; Zhou, Tianjun; Lin, Ailan; Wu, Bo; Gu, Dejun; Li, Chunhui; Zheng, Bin

    2015-11-26

    The Western North Pacific Subtropical High (WNPSH) regulates East Asian climate in summer. Anomalous WNPSH causes floods, droughts and heat waves in China, Japan and Korea. The potential change of the WNPSH under global warming is concerned by Asian people, but whether the WNPSH would be enhanced or weakened remains inconclusive. Based on the multi-model climate change projection from the 5th phase of Coupled Model Intercomparison Project (CMIP5), we show evidences that the WNPSH tends to weaken and retreat eastward in the mid-troposphere in response to global warming, accompanied by an eastward expansion of East Asian rain belt along the northwestern flank of WNPSH. Weakened meridional temperature gradient on the northern flank of WNPSH and the associated thermal wind account for the weakened WNPSH in the mid troposphere. We recommend the WNPSH be measured by eddy geopotential height (He) instead of traditionally used geopotential height, especially in climate change studies.

  9. Chemical Composition of the Volatile Components of Tropaeolum majus L. (Garden Nasturtium from North Western Algeria

    Directory of Open Access Journals (Sweden)

    B. BENYELLES

    2015-11-01

    Full Text Available Essential oil from Tropaeolum majus L. aerial parts, a plant native to North Western Algeria, was obtained by hydrodistillation. The oil volatile components were identified by a combination of gas chromatography/flame ionization detection (GC/FID, GC-mass spectrometry (GC-MS techniques, and NMR spectroscopy. Nine components representing 92.0 % of the essential oil total (GC/FID chromatogram were identified. The most abundant compounds were benzyl isothiocyanate (82.5 %, benzene acetonitrile (3.9 % and 2-phenylethyl isovalerate (2.9 %. Higher content in nitrogen- and sulfur-containing compounds accounting to 86.4 % of the volatile fraction composition of T. majus were quantified.

  10. Transport process of Pu isotope in marginal seas of the western North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masatoshi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, Hirosaki, 036-8564, Aomori (Japan); Zheng, Jian [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, 263-8555, Chiba (Japan)

    2014-07-01

    Significant quantities of Pu isotopes have been released into the marine environment as the result of atmospheric nuclear weapons testing. Most radionuclides globally dispersed in atmospheric nuclear weapons testing were released into the environment during the 1950's and 1960's. In the western North Pacific Ocean, the principal source can be further distinguished as two distinct sources of Pu: close-in tropospheric fallout from nuclear weapons testing at the Pacific Proving Grounds (PPG) in the Marshall Islands and global stratospheric fallout. Since the {sup 240}Pu/{sup 239}Pu atom ratio is characteristic for the Pu emission source, information on Pu isotopic signature is very useful to better understand the transport process in the oceans and to identify the sources of Pu. The mean atom ratio of {sup 240}Pu/{sup 239}Pu from the global stratospheric fallout is 0.180 ±0.014 based on soil sample data, whereas that from close-in tropospheric fallout from the PPG is 0.33 - 0.36. The {sup 240}Pu/{sup 239}Pu atom ratios in seawater samples collected in marginal seas of the western North Pacific Ocean will provide important and useful data for understanding the process controlling Pu transport and for distinguishing future Pu sources. The objectives of this study were to measure the {sup 239+240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios in seawater from the Sea of Okhotsk, Japan Sea, South China Sea and Sulu Sea and to discuss the transport process of Pu. Large-volume seawater samples (250 L each) were collected from the surface to the bottom in marginal seas of the western North Pacific Ocean with acoustically triggered quadruple PVC sampling bottles during the R/V Hakuho-Maru cruise. The {sup 239}Pu and {sup 240}Pu concentrations and {sup 240}Pu/{sup 239}Pu atom ratios were measured with a double-focusing SF-ICP-MS, which was equipped with a guard electrode to eliminate secondary discharge in the plasma and to enhance overall sensitivity. In

  11. Problems encountered and approaches for the deployment of advanced reactors in Western Europe and North America

    International Nuclear Information System (INIS)

    The deployment of nuclear energy faces stagnation in Western European and North American countries as a result of 'barriers' that have appeared over the years. Such barriers were identified in the areas of economics, public acceptance, energy policy, technology, licensing and regulations, as well as the environment and waste disposal. They are institutional rather than technical and originate from all sectors of society: industry, government, the authorities and the public. However, it is up to the nuclear community, and particularly the industry (i.e. utilities and nuclear vendors), to take the initiative and the leadership role for the most significant approaches to overcome these barriers. The paper describes the barriers in a systematic way and proposes appropriate measures to overcome them. 3 refs, 1 fig

  12. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

    Science.gov (United States)

    Eads, David A; Biggins, Dean E

    2015-08-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. PMID:25817984

  13. Climate change increases deoxynivalenol contamination of wheat in north-western Europe

    DEFF Research Database (Denmark)

    van der Fels-Klerx, H J; Olesen, Jørgen E; Madsen, M S;

    2012-01-01

    will be earlier in the season because of climate change effects, about 1 to 2 weeks. Deoxynivalenol contamination was found to increase in most of the study region, with an increase of the original concentrations by up to 3 times. The study results may inform governmental and industrial risk managers to underpin......Climate change will affect the development of cereal crops and the occurrence of mycotoxins in these crops, but so far little research has been done on quantifying the expected effects. The aim of this study was to assess climate change impacts on the occurrence of deoxynivalenol in wheat grown...... in north-western Europe by 2040, considering the combined effects of shifts in wheat phenology and climate. The study used climate model data for the future period of 2031–2050 relative to the baseline period of 1975–1994. A weather generator was used for generating synthetic series of daily weather data...

  14. Difference of mercury bioaccumulation in red mullets from the north-western Mediterranean and Black seas

    International Nuclear Information System (INIS)

    The relationships between total mercury (Hg) concentration and stable nitrogen isotope ratio (δ15N) were evaluated in Mullus barbatus barbatus and M. surmuletus from the Mediterranean Sea and M. barbatus ponticus from the Black Sea. Mercury concentration in fish muscle was six times higher in the two Mediterranean species than in the Black Sea one for similar sized animals. A positive correlation between Hg concentration and δ15N occurred in all species. Increase in Hg concentration with δ15N was high and similar in the two Mediterranean fishes and much lower in the Black Sea species. Since this was neither related to trophic level difference between species nor to methylmercury (MeHg) concentration differences between the north-western Mediterranean and the Black Sea waters, we suggested that the higher primary production of the Black Sea induced a dilution of MeHg concentration at the base of the food webs.

  15. A review of the studies on modern process for climatic proxies in north-western China

    Institute of Scientific and Technical Information of China (English)

    Jinghui SUN; Furong LI; Wenwei ZHAO; Yu TANG

    2011-01-01

    This paper reviews the modem process studies for four types of proxies(tree-ring,biologic indicators,physical proxies and geochemical indexes)in arid northwestern China for the purpose of better understanding their environmental indication for reconstructing paleoenvironment and palcoclimate.These proxies are affected by many variables in some cases,such as temperature,precipitation,pH,topography etc.,and their indicative meanings may become complex sometimes.For this reason,multiple proxies might be used to complement each other if conditions permit.Moreover,potential differences of each proxy should be taken into consideration when they were used.This paper indicates the application of each modem process proxy and their advantages and disadvantages,so as to give some references to fossil data interpretation and environment reconstruction in arid north-western China.

  16. Spatiotemporal patterns of mercury accumulation in lake sediments of western North America

    Science.gov (United States)

    Drevnick, Paul; Cooke, Colin A.; Barraza, Daniella; Blais, Jules M.; Coale, Kenneth; Cumming, Brian F.; Curtis, Chris; Das, Biplob; Donahue, William F.; Eagles-Smith, Collin A.; Engstrom, Daniel R.; Fitzgerald, William F.; Furl, Chad V.; Gray, John R.; Hall, Roland I.; Jackson, Togwell A.; Laird, Kathleen R.; Lockhart, W. Lyle; Macdonald, Robie W.; Mast, M. Alisa; Mathieu, Callie; Muir, Derek C.G.; Outridge, Peter; Reinemann, Scott; Rothenberg, Sarah E.; Ruiz-Fernandex, Ana Carolina; St. Louis, V.L.; Sanders, Rhea; Sanei, Hamed; Skierszkan, Elliott; Van Metre, Peter C.; Veverica, Timothy; Wiklund, Johan A.; Wolfe, Brent B.

    2016-01-01

    For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.2 μg/m2 per year. Lakes with the greatest increases were influenced by the Flin Flon smelter, followed by lakes directly affected by mining and wastewater discharges. Of lakes not directly affected by point sources, there is a clear separation in mercury accumulation rates between lakes with no/little watershed development and lakes with extensive watershed development for agricultural and/or residential purposes. Lakes in the latter group exhibited a sharp increase in mercury accumulation rates with human settlement, stabilizing after 1950 at five times (5×) 1850 rates. Mercury accumulation rates in lakes with no/little watershed development were controlled primarily by relative watershed size prior to 1850, and since have exhibited modest increases (in absolute terms and compared to that described above) associated with (regional and global) industrialization. A sub-regional analysis highlighted that in the ecoregion Northwestern Forest Mountains, <1% of mercury deposited to watersheds is delivered to lakes. Research is warranted to understand whether mountainous watersheds act as permanent sinks for mercury or if export of “legacy” mercury (deposited in years past) will delay recovery when/if emissions reductions are achieved.

  17. Ocean acidification from 1997 to 2011 in the subarctic western North Pacific Ocean

    Directory of Open Access Journals (Sweden)

    M. Wakita

    2013-05-01

    Full Text Available Rising atmospheric CO2 contents have led to greater CO2 uptake by the oceans, lowering both pH due to increasing hydrogen ions and CaCO3 saturation states due to declining carbonate ion (CO32−. Here, we used previously compiled data sets and new data collected in 2010 and 2011 to investigate ocean acidification of the North Pacific western subarctic gyre. In winter, the western subarctic gyre is a source of CO2 to the atmosphere because of convective mixing of deep waters rich in dissolved inorganic carbon (DIC. We calculated pH in winter mixed layer from DIC and total alkalinity (TA, and found that it decreased at the rate of −0.001 ± 0.0004 yr−1 from 1997 to 2011. This decrease rate is slower than that expected under condition of seawater/atmosphere equilibration, and it is also slower than the rate in the subtropical regions (−0.002 yr−1. The slow rate is caused by a reduction of CO2 emission in winter due to an increase in TA. Below the mixed layer, the calcite saturation horizon (~185 m depth shoaled at the rate of 2.9 ± 0.9 m yr−1 as the result of the declining CO32− concentration (−0.03 ± 0.01 μmol k−1yr−1. Between 200 m and 300 m depth, pH decline during the study period (−0.0051 ± 0.0010 yr−1 was larger than ever reported in the open North Pacific. This enhanced acidification rate below the calcite saturation horizon reflected not only the uptake of anthropogenic CO2 but also the increase in the decomposition of organic matter evaluated from the increase in AOU, which suggests that the dissolution of CaCO3 particles increased.

  18. Impact of oil pollution on the North-western coast of Morocco

    Science.gov (United States)

    Aksissou, M.

    2003-04-01

    The North-western coast of Morocco has approximately 160 km from Asila city while passing by the towns of Tangier, Fnideq, M'diq and Tetouan to Oued Laou and shelters wetlands (lake Smir.), beaches, cliffs and mountains. Investigations carried out in 2000-2001 in this zone show scattered beaches and wetlands (Smir lake, Maleh river) polluted by oil. These polluted beaches and coastal wetlands are generally close to Marina or fishing ports and to the residential areas. Cases of fish (Rays and other Chondrychtiens), tortoises (Caretta caretta) and dolphins dead have been noted in some of these beaches during spring and summer (2000-2001) most probably because of oil pollution. Increased dredging in beaches (Haouara, Martil...) involves the salinity of the ground water and the disturbance of the marine biodiversity. Some management (construction of Kabila marina and Smir dam) involved disturbance of hydrology (salinity increased) and biodiversity (migration of the Birds from Smir lake towards Smir dam) in Smir lake. This management, dredging, algae extraction and oil act on the coastal biodiversity and involve the deterioration of the natural environment. The beaches polluted by oil obstruct the tourism activity. Measurements of prevention (by prohibition to get rid of the motor oil and the washing of the boats on the open sea, construction of sewage stations and industrial water purification) are necessary for the conservation of biological diversity and the tourism development. The cleaning of the beaches polluted within the framework of the activities of the ONG or the local communities is also necessary. An integrated coastal zone management is necessary for the nature conservation and the sustainable development of the North Western of Morocco. Keywords: Oil pollution, Biodiversity, Coast, Morocco.

  19. Hg concentrations in fish from coastal waters of California and Western North America.

    Science.gov (United States)

    Davis, J A; Ross, J R M; Bezalel, S; Sim, L; Bonnema, A; Ichikawa, G; Heim, W A; Schiff, K; Eagles-Smith, C A; Ackerman, J T

    2016-10-15

    The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3μg/gwet weight (ww), and 10 locations an average above 1.0μg/gww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds. PMID:27067833

  20. Hg concentrations in fish from coastal waters of California and Western North America

    Science.gov (United States)

    Davis, Jay; Ross, John; Bezalel, Shira; Sim, Lawrence; Bonnema, Autumn; Ichikawa, Gary; Heim, Wes; Schiff, Kenneth C; Eagles-Smith, Collin A.; Ackerman, Josh

    2016-01-01

    The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3 μg/g wet weight (ww), and 10 locations an average above 1.0 μg/g ww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

  1. Convective and Precipitation Properties of Tropical Cyclone in the Western North Pacific as Observed by TRMM Satellite

    Science.gov (United States)

    Yuan, T.; Yang, C.

    2015-12-01

    The convective properties and three-dimension structure of precipitation in the inner-core (IC), inner rainband (IB), and outer rainband (OB) regions of tropical cyclones (TCs) in the western north Pacific basin have been studied by using the data from the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR), Microwave Imager (TMI), Lightning Imaging Sensor (LIS) and best-track data during the period from 1998 to 2013. It is found that stratiform precipitation is dominated in all regions of TCs, especially in IB, the proportion of convective precipitation is highest in IC regions and the proportion of stratiform precipitation is highest in IB regions. The highest average precipitation rate of convective precipitation, stratiform precipitation and other precipitation occur in IC regions, and the lowest occur in OB regions. Only 1.1% of all the precipitation features have maximum 20-dBZ radar echo ≥ 14 km, which contribute 24.4% of rainfall and 70.0% of lightning. The precipitation features in IC regions have much stronger radar echoes and ice scattering (i.e. lower 85 GHz PCT) than those in IB and OB regions, which indicates that the strongest convections appear in IC region, and the convection intensity increases as the TC intensity increases. Stronger convective cells also occur in IC regions, but there strength changes little during different TC categories. There is significant difference of flash density of precipitation feature normalized by the raining area in IC and OB regions among different TC categories, and the lowest flash density is always found in IB regions. The flash density in OB features is 1.2 times higher than that in IC features for all TC categories, the flash density in IC features 2.4 times higher than that in OB features for CAT35 TCs, but the flash rate of both precipitation features and convective cells in IC regions is highest except for CAT12 TCs

  2. The East Asia-Western North Pacific Boreal Summer Intraseasonal Oscillation Simulated in GAMIL 1.1.1

    Institute of Scientific and Technical Information of China (English)

    YANG Jing; Bin WANG; WANG Bin; LI Lijuan

    2009-01-01

    We evaluate the performance of GAMIL1.1.1 in a 27-year forced simulation of the summer intraseasonal oscillation (ISO) over East Asia (EA)-western North Pacific (WNP). Thc assessment is based on two mea- sures: climatological ISO (CISO) and transient ISO (TISO). CISO is the ISO component that is phase-locked to the annual cycle and describes seasonal march. TISO is the ISO component that varies year by year. The model reasonably captures many observed features of the ISO, including the stepwise northward advance of the rain belt of CISO, the dominant periodicities of TISO in both the South China Sea-Philippine Sea (SCS-PS) and the Yangtze River Basin (YRB), the northward propagation of 30-50-day TISO and the westward propagation of the 12 25-day TISO mode over the SCS-PS, and the zonal propagating features of three major TISO modes over the YRB. However, the model has notable deficiencies. These include the early onset of the South China Sea monsoon associated with CISO, too fast northward propagation of CISO from 20°N to 40°N and the absence of the CISO signal south of 10°N, the deficient eastward propagation of the 30-50-day TISO mode and the absence of a southward propagation in the YRB TISO modes. Tile authors found that the deficiencies in the ISO simulation are closely related to the model's biases in the mean states, suggesting that the improvement of the model mean state is crucial for realistic simulation of the intraseasonal variation.

  3. The Association Between the North Atlantic Oscillation and the Interannual Variability of the Tropospheric Transport Pathways in Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Orza, J.A.G.; Cabello Ganuza, M.; Galiano, V. [SCOLAb, Fca Aplicada, Universidad Miguel Hernez, Elche (Spain); Vermeulen, A.T. [Environmental Assessment, ECN-Energy Research Centre of the Netherlands, Petten (Netherlands); Stein, A.F. [Earth Resources Technology, Inc., Laurel, Maryland (United States)

    2013-03-15

    The variations in tropospheric transport pathways over a 20 year period, 1990-2009, are studied at six locations in Europe. Three Atlantic (Lisbon, Mace Head, and Cabauw) and three Mediterranean sites (Malaga and Elche in the western part and Lecce in the central Mediterranean) are considered. The work is based on the identification of flow types at each location by robust cluster analysis of the trajectories, the assessment of temporal trends for each advection pattern, and subsequent quantification of the association, at the monthly scale, between the North Atlantic Oscillation (NAO) index (NAOi) and the frequency of occurrence of the identified flows. This exploratory study demonstrates the usefulness of the approach for specific locations in a context where synoptic circulation/weathertype classifications are usually used. A different number of advection pathways were identified at each location. Common features to all the sites were prevalence of westerly flows, strong seasonal variability, and association of the air flow types to known synoptic situations in both phases of the NAO. The degree of association varies strongly with latitude, location within the Mediterranean basin, and closeness to the action centers. Overall, flows reaching Mace Head and Cabauw present stronger association to the NAO, which is substantially reduced at lower latitudes and is not significant at Lisbon. Significant temporal trends are found for northerly flows at Mace Head and Malaga, associated to changes at the beginning of the study period that are also present in the NAOi time series. WSW flows at Mace Head exhibit a steady decreasing trend over the whole period.

  4. The neo-tectonic deformation features in the eastern segment of Circum-Tibetan Plateau Basin and Range System:Take the western Sichuan basin as an example%环青藏高原盆山体系东段新构造变形特征——以川西为例

    Institute of Scientific and Technical Information of China (English)

    李本亮; 雷永良; 陈竹新; 贾东; 张朝军

    2011-01-01

    介于扬子板块与青藏高原之间的川西前陆冲断带是环青藏高原盆山体系东段的重要组成部分,它是研究喜马拉雅构造运动对青藏高原东缘沉积盆地构造作用的重要场所.本文分别选取川西南段、川西北段和川北西段米仓山前的区城构造地质剖面来研究沉积地层在喜马拉雅运动中发生的构造变形特征.通过前陆冲断构造变形带的宽度、水平缩短童,山体隆升、盆地沉降,新构造对早期古构造的叠加与改造关系的研究,揭示出在环青藏高原盆山体系内,造山带与盆地边缘的冲断构造变形从造山带向克拉通盆地内扩展的同时受欧亚大陆与印度板块碰撞及其远程效应的空间位置限制,靠近青藏高原的川西南段到远离它的川北西段,新构造变形强度、新构造变形范围、盆山耦合程度具有依次降低等特征.这种受环青藏高原盆山体系控制的前陆冲断带构造变形具有明显的资环效应,特别是对油气资源的聚集与分布有重要的影响,控制了川西南段晚期次生气藏发育,川西北段和川北西段的早期原生气藏的发育.%The western Sichuan basin foreland thrust and fold belt locate between the Tibetan Plateau and Upper Yangtze plate, which is the main part of the eastern segment of Circum-Tibetan Plateau Basin and Range System formed during the Himalayan tectonic movement. There are different neo-tectonic deformation features in the different areas. The long geologic profile cross the whole foreland thrust and fold belt in the south segment of western Sichuan basin, north segment of western Sichuan basin and west segment of northern Sichuan basin, are compiled to study the neo-tectonic features and distribution. After comparing their deformation width of foreland thrust and fold belt, structural shortening amount, lifted mountain altitude, basin subsidence and the space relation between old structure and neo-structure, authors

  5. Nutrients, suspended sediment, and pesticides in waters of the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1970-90

    Science.gov (United States)

    Tornes, L.H.; Brigham, M.E.

    1994-01-01

    Available data on nutrients (phosphorus and nitrogen), suspended sediment, and pesticides in the Red River of the North Basin, a study unit under the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program, are reviewed. These data were collected by several agencies during 1970-90. Nutrient concentrations in surface water are higher downgradient from agricultural and urban areas than in other areas, but generally do not exceed U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs). The 10 milligram per liter (mg/L) drinking water MCL for nitrate (as nitrogen) was rarely exceeded. Some of the largest nutrient inputs to the surface-water system appear to come from the Fargo-Moorhead area. The highest nitrogen concentrations usually were found in the Red River of the North. Nitrogen composition was mostly organic nitrogen with some nitrate. Ammonia nitrogen was negligible except during mid-winter, when concentrations could exceed 1.0 mg/L. Streams draining the corn-dominated cropland in the southern part of the basin had relatively high nitrogen concentrations compared to parts of the basin where small-grain crops, forests, and wetlands predominate. The Pembina River in the northern part of the basin had a large range in nitrogen concentrations that often exceeded those in the Red River of the North. The highest phosphorus concentrations generally were found in of the Red River of the North, although tributary streams occasionally had peak concentrations that exceeded those in the Red River of the North. Median nitrate concentrations in ground water were less than 1.0 mg/L as nitrogen in all counties in the basin except in Otter Tail and Decker Counties in Minnesota. Half of the wells in Otter Tail County had nitrate-nitrogen concentrations exceeding 2.8 mg/L. Shallow, surficial aquifers tended to have the highest nitrate concentrations.

  6. Regional trends in radiogenic heat generation in the Precambrian basement of the Western Canadian Basin

    Science.gov (United States)

    Jones, F. W.; Majorowicz, J. A.

    Radiogenic heat generation values for 381 basement samples from 229 sites in the western Canadian basin exhibit a lognormal frequency distribution. The mean value = 2.06 (S.D. = 1.22) µWm-3 is larger than the radiogenic heat generation values reported for the shield in the Superior (ca. 1.2 µWm-3, Jessop and Lewis, 1978) and Churchill (ca. 0.7 µWm-3, Drury, 1985) provinces. When equal Log A contour intervals are used to map the basement heat generation, three large zones of relatively high heat generation are found. One coincides with the Peace River Arch basement structure and one with the Athabasca axis (Darnley, 1981). There is no apparent indication of increased heat flow through the Paleozoic formations associated with these two zones. The third zone, in southwestern Saskatchewan, coincides with a high heat flow zone in the Swift Current area. The lack of correlation between heat flow and heat generation in Alberta may be due to the disturbance to the heat flow in the Paleozoic formations by water motion, or may indicate that the heat is from uranium, thorium and potassium isotope enrichment near the basement surface rather than enrichment throughout the entire upper crust.

  7. Fractured rock aquifer test in the Western Siberian Basin, Ozyorsk, Russia

    International Nuclear Information System (INIS)

    A series of multi-zone pumping tests was conducted in a contaminated fractured rock aquifer in the Western Siberian Basin, Ozyorsk, Russia. The tests were conducted adjacent to the Mishelyak River floodplain in fractured Paleozoic porphyrites, tufts, tuff breccia, and lava typical of the Ural mountain complex. Geophysical logs, borehole photography, core samples, and results from previous borehole contamination studies were used to identify the zones to be tested. A network of three uncased wells was tested using a system of inflatable packers, pressure transducers and data loggers. Seven zones were isolated and monitored in two of the uncased wells. A straddle packer assembly was used to isolate individual zones within the pumping well. Eight constant rate pumping tests were conducted. Results of the testing indicate that shallow groundwater migrates primarily in two intervals that are separated by an interval with low lateral conductivity. The water bearing intervals have moderate to high specific capacities (1.3 and 30 L/min/m). Several processes are responsible for fracturing present in the lower interval. The network of compound fractures produced a complex array of fracture intersections yielding a fractured media with hydraulic behavior similar to porous media. Models used for the analysis of pumping tests in porous media provide a good estimation of the hydraulic response of the lower interval to pumping. Future work will include more complex analysis of the data to determine hydraulic conductivity ellipses

  8. Fractured rock aquifer tests in the Western Siberian Basin, Ozyorsk, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, R.L.; Looney, B.B.; Eddy-Dilek, C.A. [and others

    1997-10-01

    A series of multi-zone pumping tests was conducted in a contaminated fractured rock aquifer in the Western Siberian Basin, Ozyorsk, Russia. The tests were conducted adjacent to the Mishelyak River floodplain in fractured Paleozoic porphyrites, tufts, tuff breccia, and lava typical of the Ural mountain complex. Geophysical logs, borehole photography, core samples, and results from previous borehole contamination studies were used to identify the zones to be tested. A network of three uncased wells was tested using a system of inflatable packers, pressure transducers and data loggers. Seven zones were isolated and monitored in two of the uncased wells. A straddle packer assembly was used to isolate individual zones within the pumping well. Eight constant rate pumping tests were conducted. Results of the testing indicate that shallow groundwater migrates primarily in two intervals that are separated by an interval with low lateral conductivity. The water bearing intervals have moderate to high specific capacities (1.3 and 30 L/min/m). Several processes are responsible for fracturing present in the lower interval. The network of compound fractures produced a complex array of fracture intersections yielding a fractured media with hydraulic behavior similar to porous media. Models used for the analysis of pumping tests in porous media provide a good estimation of the hydraulic response of the lower interval to pumping. Future work will include more complex analysis of the data to determine hydraulic conductivity ellipses.

  9. Tritium clouds environmental impact in air into the Western Mediterranean Basin evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Castro, P., E-mail: paloma.castro@ciemat.es [EURATOM-CIEMAT Association, LNF Fusion National Laboratory, BBTU, Avda Complutense,40 28040 Madrid (Spain); Velarde, M. [ETSII Nuclear Fusion Institute: DENIM, Madrid (Spain); Ardao, J. [AEMET, Environmental Applications Service, 28040 Madrid (Spain); Perlado, J.M. [ETSII Nuclear Fusion Institute: DENIM, Madrid (Spain); Sedano, L. [EURATOM-CIEMAT Association, LNF Fusion National Laboratory, BBTU, Avda Complutense,40 28040 Madrid (Spain)

    2012-08-15

    The paper considers short-term releases of tritium (mainly but not only tritium hydride (HT)) to the atmosphere from a potential ITER-like fusion reactor located in the Mediterranean Basin and explores if the short range legal exposure limits are exceeded (both locally and downwind). For this, a coupled Lagrangian ECMWF/FLEXPART model has been used to follow real time releases of tritium. This tool was analyzed for nominal tritium operational conditions under selected incidental conditions to determine resultant local and Western Mediterranean effects, together with hourly observations of wind, to provide a short-range approximation of tritium cloud behavior. Since our results cannot be compared with radiological station measurements of tritium in air, we use the NORMTRI Gaussian model. We demonstrate an overestimation of the sequence of tritium concentrations in the atmosphere, close to the reactor, estimated with this model when compared with ECMWF/FLEXPART results. A Gaussian 'mesoscale' qualification tool has been used to validate the ECMWF/FLEXPART for winter 2010/spring 2011 with a database of the HT plumes. It is considered that NORMTRI allows evaluation of tritium-in-air-plume patterns and its contribution to doses.

  10. Managing the Cumulative Impacts of Land Uses in the Western Canadian Sedimentary Basin: A Modeling Approach

    Directory of Open Access Journals (Sweden)

    Stan Boutin

    2003-07-01

    Full Text Available This case study from northeastern Alberta, Canada, demonstrates a fundamentally different approach to forest management in which stakeholders balance conservation and economic objectives by weighing current management options from the point of view of their long-term effects on the forest. ALCES®, a landscape-scale simulation model, is used to quantify the effects of the current regulatory framework and typical industrial practices on a suite of ecological and economic indicators over the next 100 yr. These simulations suggest that, if current practices continue, the combined activities of the energy and forestry industries in our 59,000 km2 study area will cause the density of edge of human origin to increase from 1.8 km/km 2 to a maximum of 8.0 km/km2. We also predict that older age classes of merchantable forest stands will be largely eliminated from the landscape, habitat availability for woodland caribou will decline from 43 to 6%, and there will be a progressive shortfall in the supply of softwood timber beginning in approximately 60 yr. Additional simulations involving a suite of "best practices" demonstrate that substantial improvements in ecological outcome measures could be achieved through alternative management scenarios while still maintaining a sustainable flow of economic benefits. We discuss the merits of our proposed approach to land use planning and apply it to the Western Canadian Sedimentary Basin.

  11. Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa

    Directory of Open Access Journals (Sweden)

    Leon Prozesky

    2016-03-01

    Full Text Available The north-western part of South Africa, in particular, is well known for mineral imbalances. Aphosphorosis, resulting in rickets and osteomalacia, received a lot of attention at the turn of the nineteenth century (1882–1912. This was followed in 1997 by research on Vryburg hepatosis, another area-specific mineral imbalance–related disease in young calves reared on manganese-rich soil derived from the weathering of dolomitic (carbonate rock formations. In 1982, a totally new syndrome (osteochondrosis manifested in, amongst others, areas in South Africa where aphosphorosis was rife. Osteochondrosis was also identified in the south-western parts of Namibia as well as southern Botswana and other areas in South Africa. Osteochondrosis has a multifactorial aetiology and this study focused on the role of minerals, particularly phosphorus, in the development of the disease. A significant improvement in the clinical signs in experimental animals and a reduction of osteochondrosis occurred on farms where animals received bioavailable trace minerals and phosphorus as part of a balanced lick. An increase in the occurrence of the disease on farms during severe drought conditions in 2012–2013 prompted researchers to investigate the possible role of chronic metabolic acidosis in the pathogenesis of the disease.

  12. THE EFFECT OF WARM POOL THERMAL STATES ON TROPICAL CYCLONES IN THE WESTERN NORTH PACIFIC

    Institute of Scientific and Technical Information of China (English)

    CHEN Guang-hua; HUANG Rong-hui

    2007-01-01

    The influence of thermal states in the warm pool on tropical cyclones (TCs) in the western North Pacific (WNP) is investigated. There are fewer typhoons during warm years of the warm pool in which tropical storms tend to form in the northwest quadrant and move westward. Inversely, typhoons tend to recurve northeastward to the southeast of Japan and increase in number in the southeast quadrant during cold years. Based on composite analyses, circulation-induced dynamic factors rather than thermal factors are identified as being responsible for TCs activities. During the warm state, the monsoon trough retreats westwards, which leads to anomalous vorticity in low-level and divergence in high-level in the western part of west Pacific. Above-normal TCs activity is found in this area. Furthermore, wind anomalies at 500 hPa determine the main track types. On the contrary, when the warm pool is in cold state, the atmospheric circulation is responsible for the formation of more TCs in the southeast quadrant and recurving track.

  13. Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa.

    Science.gov (United States)

    Prozesky, Leon; Neser, Johan; Meissner, Heinz; Botha, Kenneth; Jacobs, Lubbe; Shepstone, Craig; Viljoen, Hannes; Köster, Hinner; De Brouwer, Chris; Van Zyl, Jan; Van der Veen, Gerjan

    2016-01-01

    The north-western part of South Africa, in particular, is well known for mineral imbalances. Aphosphorosis, resulting in rickets and osteomalacia, received a lot of attention at the turn of the nineteenth century (1882-1912). This was followed in 1997 by research on Vryburg hepatosis, another area-specific mineral imbalance-related disease in young calves reared on manganese-rich soil derived from the weathering of dolomitic (carbonate) rock formations. In 1982, a totally new syndrome (osteochondrosis) manifested in, amongst others, areas in South Africa where aphosphorosis was rife. Osteochondrosis was also identified in the south-western parts of Namibia as well as southern Botswana and other areas in South Africa. Osteochondrosis has a multifactorial aetiology and this study focused on the role of minerals, particularly phosphorus, in the development of the disease. A significant improvement in the clinical signs in experimental animals and a reduction of osteochondrosis occurred on farms where animals received bioavailable trace minerals and phosphorus as part of a balanced lick. An increase in the occurrence of the disease on farms during severe drought conditions in 2012-2013 prompted researchers to investigate the possible role of chronic metabolic acidosis in the pathogenesis of the disease. PMID:27543146

  14. Using technology for E and P success - the practices of leader companies in Western Canada Sedimentary Basin strategies

    International Nuclear Information System (INIS)

    The technologies that create a competitive advantage for the leaders in various exploration and production (E and P) strategies were demonstrated. The western Canadian E and P industry has evolved since the oil price shock of 1986 and the gas price shock of 1990-92. Performance of the leaders in broadly defined E and P strategy areas in the western Canada Sedimentary Basin are compared. Success of the industry as a whole was evaluated based on measurement of one of the most critical success factors, technology utilization

  15. Collapse of the western North America climate dipole during the MCA and LIA

    Science.gov (United States)

    Asmerom, Y.; Polyak, V. J.; Rasmussen, J.; Burns, S. J.; Lachniet, M. S.

    2011-12-01

    Understanding of the teleconnections between regional climate regimes and the time-scale of the stability of these teleconnections is crucial for building predictive models of climate change. Using annually-resolved speleothem physical (band thickness, hiatus and mineralogy) and oxygen and carbon isotopic effective moisture proxy data, we show climate variability in the southwestern United States (SW) during the critical Medieval Climate Anomaly and Little Ice Age (LIA) intervals. Although the MCA overall was not markedly drier than the wet latter half of the LIA, it was punctuated by multiple megadroughts. The driest interval was the early LIA, during which we identify an extended multi-century drought, which we will refer to as a Super Drought (SD), occurring during the early LIA ca. AD 1350 to AD 1650. There is a well-established dipole response to Pacific Decadal Oscillation (PDO) and El Nino-Southern Oscillation (ENSO) variability between the SW and northwestern United States (NW), and the SW and the Asian monsoon during the modern and overall Holocene climate regime. Our data indicate that this climate dipole apparently collapsed during the MCA-LIA, extending back to about 300 AD, such that pluvial and drought intervals in the SW and NW, and SW and Asian monsoon occur contemporaneously over this period. The modern positive relationship between moisture and the PDO observed in the SW is also reversed. During this interval the PDO is negatively correlated with SW moisture amount. In addition, the strong solar control of Holocene climate observed previously in western North America and the Asian monsoon is weakened during parts of this interval, such that solar maxima and minima do not correlate coherently with precipitation variability both in North America and the Asian monsoon. The MCA-early LIA period in which the megadroughts dominate occurs within the prominently positive phase of the North Atlantic Oscillation (NAO). One potential mechanism of propagating

  16. Assimilation of Satellite Altimetry into a Western North Pacific Operational Model

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An ocean data assimilation system, COMPASS-K (the Comprehensive Ocean Modeling, Prediction, Analysis and Synthesis System in the Kuroshio-region), has been developed at the Meteorological Research Institute (MRI). The purposes of the development are understanding ocean variability in the Kuroshio re gion as a local response to a global climate change with assimilated four-dimensional data sets, develop ment of an operational system in the Japan Meteorological Agency, and for the GODAE (Global Ocean Data Assimilation Experiment) project. The model is an eddy permitting version of an MRI-OGCM. Space-time decorrelation scales of ocean variability are estimated with TOPEX/POSEIDON (T/P) altimeter data. Subsurface temperature and salinity fields are projected from the T / P altimeter data with a statistical correlation method and are assim ilated into the model with a time-retrospective nudging scheme. Seasonal variation in the western North Pacific is investigated. Realistic space-time distribution of the physical quantities, the path of Kuroshio and its separation from Honshu are captured well. The Kuroshio volume transport is well reproduced in a reanalysis experiment of 1993. Preliminary predictability experi ments are done in February and March, 1994. Predictability diagram shows the time scale of the predictability for temperature field is about 17 days in the Kuroshio south of Japan. This time scale is smal ler than that in the North Atlantic.

  17. Dryland Salinity in the North Stirling Land Conservation District, Western Australia: Simulation and Management Options

    Science.gov (United States)

    Gomboso, J.; Ghassemi, F.; Appleyard, S. J.

    1997-01-01

    The North Stirling Land Conservation District consists of approximately 100,000 hectares north of the Stirling Range National Park, Western Australia. Clearing of land for agriculture occurred in the 1960's and early 1970's. The groundwater is highly saline, and, since clearing, the water table has risen by as much as 12 m; it is now generally less than 3 m below ground level throughout the area. The rise in groundwater levels following clearing and the use of crops and pastures requiring low water use have caused dramatic secondary salinisation over a short period of time. Groundwater flow was simulated with models of steady-state and transient groundwater flow. By incorporating economic simulations with the calibrated transient hydrogeological model, estimates of the expected gross margin losses were made. Three salinity-management strategies were simulated. Results indicate that 1) under the `do-nothing' strategy, future gross margins are expected to decline; 2) under the agronomic strategy, the rate of water-table rise would be reduced and foregone agricultural production losses would be less than the `do-nothing' strategy; and 3) under the agroforestry strategy, the water table is expected to decline in the long term, which would increase future agricultural production levels and, hence, profitability.

  18. Teleconnected ocean forcing of Western North American droughts and pluvials during the last millennium

    Science.gov (United States)

    Routson, Cody C.; Woodhouse, Connie A.; Overpeck, Jonathan T.; Betancourt, Julio L.; McKay, Nicholas P.

    2016-08-01

    Western North America (WNA) is rich in hydroclimate reconstructions, yet questions remain about the causes of decadal-to-multidecadal hydroclimate variability. Teleconnection patterns preserved in annually-resolved tree-ring reconstructed drought maps, and anomalies in a global network of proxy sea surface temperature (SST) reconstructions, were used to reassess the evidence linking ocean forcing to WNA hydroclimate variability over the past millennium. Potential forcing mechanisms of the Medieval Climate Anomaly (MCA) and individual drought and pluvial events-including two multidecadal-length MCA pluvials-were evaluated. We show strong teleconnection patterns occurred during the driest (wettest) years within persistent droughts (pluvials), implicating SSTs as a potent hydroclimate forcing mechanism. The role of the SSTs on longer timescales is more complex. Pacific teleconnection patterns show little long-term change, whereas low-resolution SST reconstructions vary over decades to centuries. While weaker than the tropical Pacific teleconnections, North Atlantic teleconnection patterns and SST reconstructions also show links to WNA droughts and pluvials, and may in part account for longer-term WNA hydroclimate changes. Nonetheless, evidence linking WNA hydroclimate to SSTs still remains sparse and nuanced-especially over long-timescales with a broader range of hydroclimatic variability than characterized during the 20th century.

  19. Taxonomy of quaternary deep-sea ostracods from the Western North Atlantic ocean

    Science.gov (United States)

    Yasuhara, Moriaki; Okahashi, H.; Cronin, T. M.

    2009-01-01

    Late Quaternary sediments from Ocean Drilling Program (ODP) Hole 1055B, Carolina Slope, western North Atlantic (32??47.041??? N, 76??17.179??? W; 1798m water depth) were examined for deep-sea ostracod taxonomy. A total of 13933 specimens were picked from 207 samples and c. 120 species were identified. Among them, 87 species were included and illustrated in this paper. Twenty-eight new species are described. The new species are: Ambocythere sturgio, Argilloecia abba, Argilloecia caju, Argilloecia keigwini, Argilloecia robinwhatleyi, Aversovalva carolinensis, Bythoceratina willemvandenboldi, Bythocythere eugeneschornikovi, Chejudocythere tenuis, Cytheropteron aielloi, Cytheropteron demenocali, Cytheropteron didieae, Cytheropteron richarddinglei, Cytheropteron fugu, Cytheropteron guerneti, Cytheropteron richardbensoni, Eucytherura hazeli, Eucytherura mayressi, Eucytherura namericana, Eucytherura spinicorona, Posacythere hunti, Paracytherois bondi, Pedicythere atroposopetasi, Pedicythere kennettopetasi, Pedicythere klothopetasi, Pedicythere lachesisopetasi, Ruggieriella mcmanusi and Xestoleberis oppoae. Taxonomic revisions of several common species were made to reduce taxonomic uncertainty in the literature. This study provides a robust taxonomic baseline for application to palaeoceanographical reconstruction and biodiversity analyses in the deep and intermediate-depth environments of the North Atlantic Ocean. ?? The Palaeontological Association, 2009.

  20. Evolution of Rotations in the Fish Creek Vallecito Basin, Western Salton Trough, CA

    Science.gov (United States)

    Housen, B. A.; Dorsey, R. J.; Janecke, S. U.; Axen, G. J.

    2006-12-01

    Rocks in the Western Salton Trough region record the history of slip on the transtensional West Salton detachment fault and initiation of younger strike-slip faults in this plate boundary zone. Spatial and temporal patterns of vertical axis rotations as determined by paleomagnetism can be used to provide valuable constraints on the structural-tectonic evolution of this area. Prior work includes the magnetostratigraphy of Plio-Pleistocene sedimentary rocks in the Fish Creek-Vallecito Basin (FCVB) (Opdyke et al., 1977; Johnson et al., 1983), who found that these rocks contain a complete record of geomagnetic field reversals spanning Pliocene-Pleistocene time. Johnson et al. (1983) also concluded that the FCVB had undergone 35° of CW rotation during the past 0.9 Ma. We resampled and reanalyzed their section, and sampled additional sedimentary and plutonic rocks in the Western Salton Trough in order to better document the history of vertical axis rotation recorded by these rocks. Results from 29 sites in the FCVB have well-defined magnetizations with two components. The first removed component in all samples is unblocked between 90 and 220 °C, and the second-removed components are unblocked between 300 and 590 °C. The second-removed components have either normal or reversed polarity. Sites from the Diablo Fm are predominantly reversed and have a mean of D = 204, I = -48.3, k = 37, α95 = 12.7°, N = 5. Sites from the middle of the section (Olla and Tapiado Fms) are predominantly normal and have a mean of D = 8.1, I = 48, k = 32, α95= 8.7°, N = 10. Sites from the upper portion of the section (Hueso Fm) have predominantly reversed polarity with means of D = 179.6, I = -43.4, k = 82, α95 = 10.2°, N = 4. Results from weakly-magnetized and deformed rocks of the La Posta pluton, on the south side of Whale Peak, have well-defined magnetizations with a group mean direction of D = 16.3, I = 37.3, k = 44, α95 = 7.4°, N = 10. The stratigraphic distribution of declination

  1. Seasonal variation of the surface North Equatorial Countercurrent (NECC) in the western Pacific Ocean

    Science.gov (United States)

    Zhao, Jun; Li, Yuanlong; Wang, Fan

    2016-03-01

    The North Equatorial Countercurrent (NECC) is an important zonal flow in the upper circulation of the tropical Pacific Ocean, which plays a vital role in the heat budget of the western Pacific warm pool. Using satellite-derived data of ocean surface currents and sea surface heights (SSHs) from 1992 to 2011, the seasonal variation of the surface NECC in the western tropical Pacific Ocean was investigated. It was found that the intensity (INT) and axis position (Y CM) of the surface NECC exhibit strikingly different seasonal fluctuations in the upstream (128°-136°E) and downstream (145°-160°E) regions. Of the two regions, the seasonal cycle of the upstream NECC shows the greater interannual variability. Its INT and YCM are greatly influenced by variations of the Mindanao Eddy, Mindanao Dome (MD), and equatorial Rossby waves to its south. Both INT and Y CM also show semiannual signals induced by the combined effects of equatorial Rossby waves from the Central Pacific and local wind forcing in the western Pacific Ocean. In the downstream region, the variability of the NECC is affected by SSH anomalies in the MD and the central equatorial Pacific Ocean. Those in the MD region are especially important in modulating the YCM of the downstream NECC. In addition to the SSH-related geostrophic flow, zonal Ekman flow driven by meridional wind stress also plays a role, having considerable impact on INT variability of the surface NECC. The contrasting features of the variability of the NECC in the upstream and downstream regions reflect the high complexity of regional ocean dynamics.

  2. Revised conceptualization of the North China Basin groundwater flow system: Groundwater age, heat and flow simulations

    Science.gov (United States)

    Cao, Guoliang; Han, Dongmei; Currell, Matthew J.; Zheng, Chunmiao

    2016-09-01

    Groundwater flow in deep sedimentary basins results from complex evolution processes on geological timescales. Groundwater flow systems conceptualized according to topography and/or groundwater table configuration generally assume a near-equilibrium state with the modern landscape. However, the time to reach such a steady state, and more generally the timescales of groundwater flow system evolution are key considerations for large sedimentary basins. This is true in the North China Basin (NCB), which has been studied for many years due to its importance as a groundwater supply. Despite many years of study, there remain contradictions between the generally accepted conceptual model of regional flow, and environmental tracer data. We seek to reconcile these contractions by conducting simulations of groundwater flow, age and heat transport in a three dimensional model, using an alternative conceptual model, based on geological, thermal, isotope and historical data. We infer flow patterns under modern hydraulic conditions using this new model and present the theoretical maximum groundwater ages under such a flow regime. The model results show that in contrast to previously accepted conceptualizations, most groundwater is discharged in the vicinity of the break-in-slope of topography at the boundary between the piedmont and central plain. Groundwater discharge to the ocean is in contrast small, and in general there are low rates of active flow in the eastern parts of the basin below the central and coastal plain. This conceptualization is more compatible with geochemical and geothermal data than the previous model. Simulated maximum groundwater ages of ∼1 Myrs below the central and coastal plain indicate that residual groundwater may be retained in the deep parts of the basin since being recharged during the last glacial period or earlier. The groundwater flow system has therefore probably not reached a new equilibrium state with modern-day hydraulic conditions. The

  3. Climatology, hydrology, and simulation of an emergency outlet, Devils Lake basin, North Dakota

    Science.gov (United States)

    Wiche, Gregg J.; Vecchia, A.V.; Osborne, Leon; Wood, Carrie M.; Fay, James T.

    2000-01-01

    Devils Lake is a natural lake in northeastern North Dakota that is the terminus of a nearly 4,000-square-mile subbasin in the Red River of the North Basin. The lake has not reached its natural spill elevation to the Sheyenne River (a tributary of the Red River of the North) in recorded history. However, geologic evidence indicates a spill occurred sometime within the last 1,800 years. From 1993 to 1999, Devils Lake rose 24.5 feet and, at the present (August 2000), is about 13 feet below the natural spill elevation. The recent lake-level rise has caused flood damages exceeding $300 million and triggered development of future flood-control options to prevent further infrastructure damage and reduce the risk of a potentially catastrophic uncontrolled spill. Construction of an emergency outlet from the west end of Devils Lake to the Sheyenne River is one flood-control option being considered. This report describes the climatologic and hydrologic causes of the recent lake level rise, provides information on the potential for continued lake-level rises during the next 15 years, and describes the potential effectiveness of an emergency outlet in reducing future lake levels and in reducing the risk of an uncontrolled spill. The potential effects of an outlet on downstream water quantity and quality in the upper Sheyenne River also are described.

  4. Patterns of genetic diversity in Hepatozoon spp. infecting snakes from North Africa and the Mediterranean Basin.

    Science.gov (United States)

    Tomé, Beatriz; Maia, João P; Salvi, Daniele; Brito, José C; Carretero, Miguel A; Perera, Ana; Meimberg, Harald; Harris, David James

    2014-03-01

    Species of Hepatozoon Miller, 1908 are blood parasites most commonly found in snakes but some have been described from all tetrapod groups and a wide variety of hematophagous invertebrates. Previous studies have suggested possible associations between Hepatozoon spp. found in predators and prey. Particularly, some saurophagous snakes from North Africa and the Mediterranean region have been found to be infected with Hepatozoon spp. similar to those of various sympatric lizard hosts. In this study, we have screened tissue samples of 111 North African and Mediterranean snakes, using specific primers for the 18S rRNA gene. In the phylogenetic analysis, the newly-generated Hepatozoon spp. sequences grouped separately into five main clusters. Three of these clusters were composed by Hepatozoon spp. also found in snakes and other reptiles from the Mediterranean Basin and North Africa. In the other two clusters, the new sequences were not closely related to geographically proximate known sequences. The phylogeny of Hepatozoon spp. inferred here was not associated with intermediate host taxonomy or geographical distribution. From the other factors that could explain these evolutionary patterns, the most likely seems series of intermediate hosts providing similar ribotypes of Hepatozoon and a high prevalence of host shifts for Hepatozoon spp. This is indicated by ribotypes of high similarity found in different reptile families, as well as by divergent ribotypes found in the same host species. This potentially low host specificity has profound implications for the systematics of Hepatozoon spp.

  5. The origin of the Great Lakes Basin, Western Mongolia: not the super flooding, but glaciated super valley

    OpenAIRE

    Khukhuudei Ulambadrakh

    2015-01-01

    Research on Morphology and genesis of the Great Lakes Basin in western Mongolia were taken relatively rarely in recent years. The present study combines the results of previous work with modern analysis of photographs and satellite images. The theory of Pleistocene glaciation which took vast areas of the northern hemisphere became the basis of the new approach. Glaciation covered the area from northwestern Mongolia to Mongolian Altai, Khangai and Khuvsgul mountain ranges. At that time, the ic...

  6. Assessment of waterlogging in agricultural megaprojects in the closed drainage basins of the Western Desert of Egypt

    OpenAIRE

    Bastawesy, M.; R. Ramadan Ali; A. Faid; Osta, M.

    2013-01-01

    This paper investigates the development of waterlogging in the cultivated and arable areas within typical dryland closed drainage basins (e.g. the Farafra and Baharia Oases), which are located in the Western Desert of Egypt. Multi-temporal remote sensing data of the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) were collected and processed to detect the land cover changes; cultivations, and the extent of water ponds and seepage channels. The Shuttle Radar Topography Mission...

  7. Response of the western North Atlantic to seasonal variability in the Southern Ocean

    Science.gov (United States)

    Ivchenko, V.; Sinha, B.; Wells, N.; Blaker, A.

    2009-04-01

    The huge seasonal variability in Antarctic sea ice distribution and concentration is well known. As a result the air-sea fluxes of heat, freshwater and momentum fluxes are strongly modified seasonally. In this study we conduct two experiments with the NEMO ocean general circulation model at 1 degree horizontal resolution. The first is a control run between January 1989 and December of 1994 forced at the surface by NCEP reanalysis. The second experiment was run for the same period of time as the control run, but all external fluxes from/to the atmosphere south of 30S are replaced by annual mean fluxes. The difference between the two experiments results in anomalies of temperature, salinity and other variables. The anomalies south of 30S are created by differences in the surface fluxes. The anomalies north of 30S are created by the influence of the Southern Ocean (SO) on the northern domain (ND). The SO anomalies can affect the ND in two ways (disregarding possible atmosphere influence): (i) slow propagation of the anomaly signal by currents and turbulence (ii) fast wave-like propagation of the anomaly signal. The propagation speed of such waves could be high. For example the barotropic Rossby waves have a wave speed of about 40 m/s. The results from the experiments show that the anomaly signal starts propagation in the South Atlantic as a barotropic planetary wave, reaching the equator within the first two days and reaching the North Atlantic in a few days. After the wave reflects from the western boundary temperature anomalies (TA) appear quickly, but with very low amplitude. However, the amplitude of the TA increases with time. Maximum values of TA occur in an area adjacent to the coast over the Southeast Newfoundland Rise (SNR). The highest values of TA can be observed after two or three years at depths between 90 and 200m: usually between 0.3 to 0.6C and occasionally even above that, up to 0.8C and 1.0C. Mesoscale patches appear after approx. 5 months with

  8. Wasatchian-Bridgerian (Eocene) paleoecology of the western interior of North America: changing paleoenvironments and taxonomic composition of omomyid (Tarsiiformes) primates.

    Science.gov (United States)

    Gunnell, G F

    1997-01-01

    Many changes in mammalian faunas occurred across the early (Wasatchian) to middle (Bridgerian) Eocene boundary as documented in the fossil record from the Western Interior of North America. One of the more striking changes took place within the tarsiiform primate family Omomyidae. In the early Eocene, omomyids were dominated, both in abundance and diversity, by the subfamily Anaptomorphinae. In the middle Eocene, the subfamily Omomyinae dominated in abundance, while both subfamilies were nearly equally diverse. Examination of a series of paleoecological indicators including leaf-margin analysis, cenogram analysis, ecological diversity analysis of trophic structure, the distribution and development of ancient soil horizons (paleosols), and the distribution of lacustrine and fluvial facies in the Bighorn and southern Green River basins of Wyoming reveals factors that may have influenced the composition of omomyid primates. Subtle but important changes occurred in paleoclimates with mean annual temperatures reaching Cenozoic maximums at the end of the Wasatchian into the early Bridgerian. Both land mammal ages were typified by subtropical, closed forested conditions, but the Bridgerian was probably more humid and wetter than the Wasatchian. Paleohabitats most commonly sampled in the Wasatchian of the Bighorn Basin are proximal and distal floodplains, while those of the Bridgerian in the southern Green River Basin are lake margins and proximal floodplains. Changes in paleoclimate may have triggered a wave of omomyine immigration near the end of the Wasatchian with omomyines entering into habitats previously occupied by anaptomorphines. Lake margin and proximal floodplain habitats are those most commonly occupied by omomyines in the Bridgerian with anaptomorphines being more common in basin margin and distal floodplain areas not commonly sampled. Omomyine immigration and sampling of differing paleohabitats are two possible explanations for the changes documented in

  9. Pre-bomb marine reservoir ages in the western north Pacific : Preliminary result on Kyoto University collection

    NARCIS (Netherlands)

    Yoneda, M; Kitagawa, H; van der Plicht, J; Uchida, M; Tanaka, A; Uehiro, T; Shibata, Y; Morita, M; Ohno, T

    2000-01-01

    The calibration of radiocarbon dates on marine materials involves a global marine calibration with regional corrections. The marine reservoir ages in the Western North Pacific have not been discussed, while it is quite important to determine the timing of palaeo-environmental changes as well as arch

  10. A revision of the fossil genus Miocepphus and other Miocene Alcidae (Aves: Charadriiformes) of the Western North Atlantic Ocean

    NARCIS (Netherlands)

    Wijnker, T.G.; Olson, S.L.

    2009-01-01

    This study reviews and describes all known fossils of Alcidae from the Miocene of the western North Atlantic. Because the majority of alcid fossils recovered from Miocene sediments are allied with the genus Miocepphus Wetmore, 1940, the genus is revised here. Three new species of Miocepphus are desc

  11. High amphibian diversity related to unexpected environmental values in a biogeographic transitional area in north-western Mexico

    NARCIS (Netherlands)

    Serrano, J.M.; Berlanga-Robles, C.A.; Ruiz-Luna, A.

    2014-01-01

    Amphibian diversity and distribution patterns in Sinaloa state (north-western Mexico) were assessed from the Global Amphibian Assessment database (GAA-2010). A geographic information system (GIS) was used to evaluate diversity based on distribution maps of 41 species, associated with environmental d

  12. Survival of non-Western first generations immigrants with stomach cancer in North East Netherlands: Short communication

    NARCIS (Netherlands)

    Siemerink, E.J.M.; Aa, van der M.A.; Siesling, S.; Hospers, G.A.P.; Mulder, N.H.

    2011-01-01

    Background: Isolated groups, such as first generation non-Western immigrants, are at risk for suboptimal utilisation of the health care system resulting in a worse outcome. Methods: From 1989 to 2007, all patients with stomach cancer were selected from the Comprehensive Cancer Centre North-East c

  13. Tropical Cyclone Activity in the North Atlantic Basin During the Weather Satellite Era, 1960-2014

    Science.gov (United States)

    Wilson, Robert M.

    2016-01-01

    This Technical Publication (TP) represents an extension of previous work concerning the tropical cyclone activity in the North Atlantic basin during the weather satellite era, 1960-2014, in particular, that of an article published in The Journal of the Alabama Academy of Science. With the launch of the TIROS-1 polar-orbiting satellite in April 1960, a new era of global weather observation and monitoring began. Prior to this, the conditions of the North Atlantic basin were determined only from ship reports, island reports, and long-range aircraft reconnaissance. Consequently, storms that formed far from land, away from shipping lanes, and beyond the reach of aircraft possibly could be missed altogether, thereby leading to an underestimate of the true number of tropical cyclones forming in the basin. Additionally, new analysis techniques have come into use which sometimes has led to the inclusion of one or more storms at the end of a nominal hurricane season that otherwise would not have been included. In this TP, examined are the yearly (or seasonal) and 10-year moving average (10-year moving average) values of the (1) first storm day (FSD), last storm day (LSD), and length of season (LOS); (2) frequencies of tropical cyclones (by class); (3) average peak 1-minute sustained wind speed () and average lowest pressure (); (4) average genesis location in terms of north latitudinal () and west longitudinal () positions; (5) sum and average power dissipation index (); (6) sum and average accumulated cyclone energy (); (7) sum and average number of storm days (); (8) sum of the number of hurricane days (NHD) and number of major hurricane days (NMHD); (9) net tropical cyclone activity index (NTCA); (10) largest individual storm (LIS) PWS, LP, PDI, ACE, NSD, NHD, NMHD; and (11) number of category 4 and 5 hurricanes (N4/5). Also examined are the December-May (D-M) and June-November (J-N) averages and 10-year moving average values of several climatic factors, including the (1

  14. Mapping the hydraulic connection between a coalbed and adjacent aquifer: example of the coal-seam gas resource area, north Galilee Basin, Australia

    Science.gov (United States)

    Jiang, Zhenjiao; Mariethoz, Gregoire; Schrank, Christoph; Cox, Malcolm; Timms, Wendy

    2016-07-01

    Coal-seam gas production requires groundwater extraction from coal-bearing formations to reduce the hydraulic pressure and improve gas recovery. In layered sedimentary basins, the coalbeds are often separated from freshwater aquifers by low-permeability aquitards. However, hydraulic connection between the coalbed and aquifers is possible due to the heterogeneity in the aquitard such as the existence of conductive faults or sandy channel deposits. For coal-seam gas extraction operations, it is desirable to identify areas in a basin where the probability of hydraulic connection between the coalbed and aquifers is low in order to avoid unnecessary loss of groundwater from aquifers and gas production problems. A connection indicator, the groundwater age indictor (GAI), is proposed, to quantify the degree of hydraulic connection. The spatial distribution of GAI can indicate the optimum positions for gas/water extraction in the coalbed. Depressurizing the coalbed at locations with a low GAI would result in little or no interaction with the aquifer when compared to the other positions. The concept of GAI is validated on synthetic cases and is then applied to the north Galilee Basin, Australia, to assess the degree of hydraulic connection between the Aramac Coal Measure and the water-bearing formations in the Great Artesian Basin, which are separated by an aquitard, the Betts Creek Beds. It is found that the GAI is higher in the western part of the basin, indicating a higher risk to depressurization of the coalbed in this region due to the strong hydraulic connection between the coalbed and the overlying aquifer.

  15. Evaluation of Weights of Evidence to Predict Epithermal-Gold Deposits in the Great Basin of the Western United States

    International Nuclear Information System (INIS)

    The weights-of-evidence method provides a simple approach to the integration of diverse geologic information. The application addressed is to construct a model that predicts the locations of epithermal-gold mineral deposits in the Great Basin of the western United States. Weights of evidence is a data-driven method requiring known deposits and occurrences that are used as training sites in the evaluated area. Four hundred and fifteen known hot spring gold-silver, Comstock vein, hot spring mercury, epithermal manganese, and volcanogenic uranium deposits and occurrences in Nevada were used to define an area of 327.4 km2 as training sites to develop the model. The model consists of nine weighted-map patterns that are combined to produce a favorability map predicting the distribution of epithermal-gold deposits. Using a measure of the association of training sites with predictor features (or patterns), the patterns can be ranked from best to worst predictors. Based on proximity analysis, the strongest predictor is the area within 8 km of volcanic rocks younger than 43 Ma. Being close to volcanic rocks is not highly weighted, but being far from volcanic rocks causes a strong negative weight. These weights suggest that proximity to volcanic rocks define where deposits do not occur. The second best pattern is the area within 1 km of hydrothermally altered areas. The next best pattern is the area within 1 km of known placer-gold sites. The proximity analysis for gold placers weights this pattern as useful when close to known placer sites, but unimportant where placers do not exist. The remaining patterns are significantly weaker predictors. In order of decreasing correlation, they are: proximity to volcanic vents, proximity to east-west to northwest faults, elevated airborne radiometric uranium, proximity to northwest to west and north-northwest linear features, elevated aeromagnetics, and anomalous geochemistry. This ordering of the patterns is a function of the quality

  16. Geochemical characteristics and genetic types of crude oils from the Tertiary system in the southern part of western Qaidam Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    LI Hongbo; ZHANG Min; ZHANG Chunming; PENG Dehua

    2008-01-01

    Crude oil samples taken from the southern part of westem Qaidam Basin were analyzed with GC/MS in order to understand the geochemical characteristics of crude oils. The results reveal that most crude oils are characterized by high abundance of gammaeerane and C35 homohopane, which are the representative characteristics of saline lacustrine crude oils. Based on the variation of the ratios of gammacerane/C30 hopane (G/H) and C35 homohopane/C34 homohopane (C35/C34H), two crude oil groups, A and B, are identified. Group-A crude oils mainly occurr in the north of the study area, with higher ratios of G/H (>0.8) and C35/C34H (>1.2), whereas group-B crude oils, selected from the south of the study area, show lower ratios of G/H (<0.8) and C35/C3aH (<1.0). In addition, group-A crude oils are distinguished into three subgroups in accordance with their different ratios of G/H and C35/C34H and different distribution characteristics of n-alkanes, isoprenoids and steranes. These may be helpful for understanding the distribution characteristics of crude oils in the southern part of western Qaidam Basin and providing clues to the forthcoming exploration of crude oils and gas.

  17. Integrating Climate and Ecosystem-Response Sciences in Temperate Western North American Mountains: The CIRMOUNT Initiative

    Science.gov (United States)

    Millar, C. I.; Fagre, D. B.

    2004-12-01

    Mountain regions are uniquely sensitive to changes in climate, vulnerable to climate effects on biotic and physical factors of intense social concern, and serve as critical early-warning systems of climate impacts. Escalating demands on western North American (WNA) mountain ecosystems increasingly stress both natural resources and rural community capacities; changes in mountain systems cascade to issues of national concern. Although WNA has long been a focus for climate- and climate-related environmental research, these efforts remain disciplinary and poorly integrated, hindering interpretation into policy and management. Knowledge is further hampered by lack of standardized climate monitoring stations at high-elevations in WNA. An initiative is emerging as the Consortium for Integrated Climate Research in Western Mountains (CIRMOUNT) whose primary goal is to improve knowledge of high-elevation climate systems and to better integrate physical, ecological, and social sciences relevant to climate change, ecosystem response, and natural-resource policy in WNA. CIRMOUNT seeks to focus research on climate variability and ecosystem response (progress in understanding synoptic scale processes) that improves interpretation of linkages between ecosystem functions and human processing (progress in understanding human-environment integration), which in turn would yield applicable information and understanding on key societal issues such as mountains as water towers, biodiversity, carbon forest sinks, and wildland hazards such as fire and forest dieback (progress in understanding ecosystem services and key thresholds). Achieving such integration depends first on implementing a network of high-elevation climate-monitoring stations, and linking these with integrated ecosystem-response studies. Achievements since 2003 include convening the 2004 Mountain Climate Sciences Symposium (1, 2) and several special sessions at technical conferences; initiating a biennial mountain climate

  18. Disentangling Middle Paleozoic sea level and tectonic events in cratonic margins and cratonic basins of North America

    Science.gov (United States)

    Bond, Gerard C.; Kominz, Michelle A.

    1991-04-01

    The cratonic margins and basins of North America contain evidence of distinct changes in relative sea level, one of the most intriguing of which occurred in middle Paleozoic time. The change in relative sea level began in Frasnian time (Late Devonian) and continued through Visean time (Middle Mississippian) in the Cordilleran miogeocline, in the Southern Oklahoma Aulacogen, in the Appalachian miogeocline and in the Michigan, Illinois, and Williston basins. The synchroneity and wide geographic distribution of this event are striking and would seem to argue for an eustatic mechanism. An estimate of the middle Paleozoic sea level rise relative to the stable craton in Iowa suggests that while a large sea level rise occurred, it is smaller than the magnitude of subsidence in the cratonic basins and margins. Flexural foreland basin models do not appear to account for the all of the events in the cratonic margins, and thermal subsidence mechanisms do not seem appropriate for the subsidence in the cratonic basins. The middle Paleozoic stratigraphic record from the North American craton and its margins, therefore, poses a basic problem of identifying a mechanism for producing a large-amplitude rise in sea level relative to the stable craton at the same time as a synchronous onset of tectonic subsidence in widespread basinal and marginal settings of diverse tectonic origin. One plausible mechanism for the tectonic subsidence in the basins and margins is a pulse of intraplate compressive stress. The origin of the large sea level rise relative to the stable craton could reflect an unusually large eustatic sea level change, but we cannot eliminate the possibility of a small component of subsidence or change in dynamic topography of the North American craton. The synchroneity of the sea level rise relative to the craton with the subsidence of basins and margins may be fortuitous, but it is also predicted by recent mantle convection models for the early stages of accretion of

  19. Base of principal aquifer for parts of the North Platte, South Platte, and Twin Platte Natural Resources Districts, western Nebraska

    Science.gov (United States)

    Hobza, Christopher M.; Abraham, Jared D.; Cannia, James C.; Johnson, Michaela R.; Sibray, Steven S.

    2014-01-01

    Water resources in the North and South Platte River valleys of Nebraska, including the valley of Lodgepole Creek, are critical to the social and economic health of the area, and for the recovery of threatened and endangered species in the Platte River Basin. Groundwater and surface water are heavily used resources, and uses are regulated in the study area. Irrigation is the dominant water use and, in most instances, is supplied by both groundwater and surface-water sources. The U.S. Geological Survey and its partners have collaborated to use airborne geophysical surveys for areas of the North and South Platte River valleys including the valley of Lodgepole Creek in western Nebraska. The objective of the surveys was to map the aquifers and underlying bedrock topography of selected areas to help improve the understanding of groundwater–surface-water relations to guide water-management decisions. This project was a cooperative study involving the North Platte Natural Resources District, the South Platte Natural Resources District, the Twin Platte Natural Resources District, the Conservation and Survey Division of the University of Nebraska-Lincoln, and the Nebraska Environmental Trust. This report presents the interpreted base-of-aquifer surface for part of the area consisting of the North Platte Natural Resources District, the South Platte Natural Resources District, and the Twin Platte Natural Resources District. The interpretations presented herein build on work done by previous researchers from 2008 to 2009 by incorporating additional airborne electromagnetic survey data collected in 2010 and additional test holes from separate, related studies. To make the airborne electromagnetic data useful, numerical inversion was used to convert the measured data into a depth-dependent subsurface resistivity model. An interpretation of the elevation and configuration of the base of aquifer was completed in a geographic information system that provided x, y, and z

  20. Formation mechanisms of heavy oils in the Liaohe Western Depression,Bohai Gulf Basin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The Liaohe Oilfield in the Liaohe Western Depression of the Bohai Gulf Basin is the third-largest oil producing province and the largest heavy oil producing oilfield in China. A total of 65 oil samples,35 rock samples and 36 reservoir sandstone samples were collected and analyzed utilizing conventional geochemical and biogeochemical approaches to unravel the mechanisms of the formation of the heavy oils. Investigation of the oils with the lowest maturity compared with the oils in the Gaosheng and Niuxintuo oilfields indicates no apparent relation between the maturity and physical properties of the heavy oils. It is suggested that the heavy oil with primary origin is not likely the main mechanism re-sponsible for the majority of the heavy oils in the Liaohe Western Slope. The absence and/or depletion of n-alkanes etc.,with relatively low molecular weight and the occurrence of 25-norhopane series in the heavy oils as well as the relatively high acidity of the oils all suggest that the majority of the heavy oils once experienced secondary alteration. The fingerprints of the total scanning fluorescence (TSF) of the inner adsorbed hydrocarbons on the reservoir grains and the included hydrocarbons in fluid inclusions are similar to that of the normal oils in the area but are different from the outer adsorbed and reser-voired free oils at present,further indicating that most of the heavy oils are secondary in origin. Analyses of bacteria (microbes) in 7 oil samples indicate that anaerobic and hyperthermophilic Ar-chaeoglobus sp. are the dominant microbes relevant to oil biodegradation,which coincides with the shallow commercial gas reservoirs containing anaerobic bacteria derived gas in the Gaosheng and Leijia teotonic belts. The biodegradation most likely occurs at the water/oil interface,where the forma-tion water is essential for microbe removal and nutrient transportation. We think that biodegradation,water washing and oxidization are interrelated and are the main

  1. Rapid inundation estimates using coastal amplification laws in the Western Mediterranean basin

    Science.gov (United States)

    Gailler, Audrey; Hébert, Hélène; Schindelé, François

    2016-04-01

    Numerical tsunami propagation and inundation models are well developed and have now reached an impressive level of accuracy, especially in locations such as harbors where the tsunami waves are mostly amplified. In the framework of tsunami warning under real-time operational conditions, the main obstacle for the routine use of such numerical simulations remains the slowness of the numerical computation, which is strengthened when detailed grids are required for the precise modeling of the coastline response of an individual harbor. Thus only tsunami offshore propagation modeling tools using a single sparse bathymetric computation grid are presently included within the French Tsunami Warning Center (CENALT), providing rapid estimation of tsunami impact at Western Mediterranean and NE Atlantic basins scale. We present here a work that performs quick estimates of the coastal impact at individual harbors from these high sea forecasting tsunami simulations. The method involves an empirical correction based on the Green's theoretical amplification law. The main limitation is that its application to a given coastal area would require a large database of previous observations, in order to define the empirical parameters of the correction equation. As no tide gage records of significant tsunamis are available for the Western Mediterranean French coasts, we use a set of points of interest distributed along these coasts, where maximum water heights are calculated for both fake events and well-known historical tsunamigenic earthquakes in the area. This synthetic dataset is obtained through accurate numerical tsunami propagation and inundation modeling by using several nested bathymetric grids of increasingly fine resolution close to the shores. Non linear shallow water tsunami modeling performed on a single 2' coarse bathymetric grid are compared to the values given by time-consuming nested grids simulations, in order to check to which extent the simple approach based on the

  2. Assessment of Undiscovered Oil and Gas Resources of the Williston Basin Province of North Dakota, Montana, and South Dakota, 2008

    Science.gov (United States)

    Anna, Lawrence O.; Pollastro, Richard M.; Gaswirth, Stephanie B.; Lewan, Michael D.; Lillis, Paul G.; Roberts, Laura N.R.; Schenk, Christopher J.; Charpentier, Ronald R.; Cook, Troy A.; Klett, Timothy R.

    2008-01-01

    Using a geology-based assessment method, the U.S. Geological Survey estimated mean undiscovered volumes of 3.8 billion barrels of undiscovered oil, 3.7 trillion cubic feet of associated/dissolved natural gas, and 0.2 billion barrels of undiscovered natural gas liquids in the Williston Basin Province, North Dakota, Montana, and South Dakota.

  3. Holocene climate variability in the North-Western Mediterranean Sea (Gulf of Lions)

    Science.gov (United States)

    Jalali, B.; Sicre, M.-A.; Bassetti, M.-A.; Kallel, N.

    2016-01-01

    Sea surface temperatures (SSTs) and land-derived input time series were generated from the Gulf of Lions inner-shelf sediments (NW Mediterranean Sea) using alkenones and high-molecular-weight odd-carbon numbered n-alkanes (TERR-alkanes), respectively. The SST record depicts three main phases: a warm Early Holocene ( ˜ 18 ± 0.4 °C) followed by a cooling of ˜ 3 °C between 7000 and 1000 BP, and rapid warming from ˜ 1850 AD onwards. Several superimposed multi-decadal to centennial-scale cold events of ˜ 1 °C amplitude were also identified. TERR-alkanes were quantified in the same sedimentary horizons to identify periods of high Rhone River discharge and compare them with regional flood reconstructions. Concentrations show a broad increase from the Early Holocene towards the present with a pronounced minimum around 2500 BP and large fluctuations during the Late Holocene. Comparison with Holocene flood activity reconstructions across the Alps region suggests that sediments of the inner shelf originate mainly from the Upper Rhone River catchment basin and that they are primarily delivered during positive North Atlantic Oscillation (NAO).

  4. A new age model for the early-middle Miocene in the North Alpine Foreland Basin

    Science.gov (United States)

    Reichenbacher, Bettina; Krijgsman, Wout; Pippèrr, Martina; Sant, Karin; Kirscher, Uwe

    2016-04-01

    The establishment of high-resolution age models for sedimentary successions is crucial for numerous research questions in the geosciences and related disciplines. Such models provide an absolute chronology that permits precise dating of depositional episodes and related processes such as mountain uplift or climate change. Recently, our work in the Miocene sediments of the North Alpine Foreland Basin (NAFB) has revealed a significantly younger age (16.6 Myr) for sediments that were thought to have been deposited 18 Myr ago. This implies that a fundamentally revised new age model is needed for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB (20 to 15-Myr). Our new data also indicate that previously published reconstructions of early-middle Miocene palaeogeography, sedimentation dynamics, mountain uplift and climate change in the NAFB all require a critical review and revision. Further, the time-span addressed is of special interest, since it encompasses the onset of a global warming phase. However, it appears that a fundamentally revised new age model for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB can only be achieved based on a 500 m deep drilling in the NAFB for which we currently seek collaboration partners to develop a grant application to the International Continental Deep Drilling Program (ICDP). Reference: Reichenbacher, B., W. Krijgsman, Y. Lataster, M. Pippèrr, C. G. C. Van Baak, L. Chang, D. Kälin, J. Jost, G. Doppler, D. Jung, J. Prieto, H. Abdul Aziz, M. Böhme, J. Garnish, U. Kirscher, and V. Bachtadse. 2013. A new magnetostratigraphic framework for the Lower Miocene (Burdigalian/Ottnangian, Karpatian) in the North Alpine Foreland Basin. Swiss Journal of Geosciences 106:309-334.

  5. Long-range Transport of Aerosol at a Mountain Site in the Western Mediterranean Basin

    Science.gov (United States)

    Roberts, Greg; Corrigan, Craig; Ritchie, John; Pont, Véronique; Claeys, Marine; Sciare, Jean; Dulac, François

    2016-04-01

    The Mediterranean Region has been identified as sensitive to changes in the hydrological cycle, which could affect the water resources for millions of people by the turn of the century. However, prior to recent observations, most climate models have not accounted for the impacts of aerosol in this region. Past airborne studies have shown that aerosol sources from Europe and Africa are often transported throughout the lower troposphere; yet, because of their complex vertical distribution, it is a challenge to capture the variability and quantify the contribution of these sources to the radiative budget and precipitation processes. The PAEROS ChArMEx Mountain Experiment (PACMEx) complemented the regional activities by collecting aerosol data from atop a mountain on the island of Corsica, France in order to assess boundary layer / free troposphere atmospheric processes. In June/July 2013, PACMEx instruments were deployed at 2000 m.asl near the center of Corsica, France to complement ground-based aerosol observations at 550 m.asl on the northern peninsula, as well as airborne measurements. Comparisons between the peninsula site and the mountain site show similar general trends in aerosol properties; yet, differences in aerosol properties reveal the myriad transport mechanisms over the Mediterranean Basin. Using aerosol physicochemical data coupled with back trajectory analysis, different sources have been identified including Saharan dust transport, residual dust mixed with sea salt, anthropogenic emissions from Western Europe, and a period of biomass burning from Eastern Europe. Each period exhibits distinct signatures in the aerosol related to transport processes above and below the boundary layer. In addition, the total aerosol concentrations at the mountain site revealed a strong diurnal cycling the between the atmospheric boundary layer and the free troposphere, which is typical of mountain-top observations. PACMEx was funded by the National Science Foundation

  6. Summary of three dimensional pump testing of a fractured rock aquifer in the western Siberian Basin

    International Nuclear Information System (INIS)

    A group of scientists from the Savannah River Technology Center and Russia successfully completed a 17 day field investigation of a fractured rock aquifer at the MAYAK PA nuclear production facility in Russia. The test site is located in the western Siberian Basin near the floodplain of the Mishelyak river. The fractured rock aquifer is composed of orphyrites, tuff, tuffbreccia and lava and is overlain by 0.5--12 meters of elluvial and alluvial sediments. A network of 3 uncased wells (176, 1/96, and 2/96) was used to conduct the tests. Wells 176 and 2/96 were used as observation wells and the centrally located well 1/96 was used as the pumping well. Six packers were installed and inflated in each of the observation wells at a depth of up to 85 meters. The use of 6 packers in each well resulted in isolating 7 zones for monitoring. The packers were inflated to different pressures to accommodate the increasing hydrostatic pressure. A straddle packer assembly was installed in the pumping well to allow testing of each of the individual zones isolated in the observation wells. A constant rate pumping test was run on each of the 7 zones. The results of the pumping tests are included in Appendix A. The test provided new information about the nature of the fractured rock aquifers in the vicinity of the Mishelyak river and will be key information in understanding the behavior of contaminants originating from process wastes discharged to Lake Karachi. Results from the tests will be analyzed to determine the hydraulic properties of different zones within the fractured rock aquifer and to determine the most cost effective clean-up approach for the site

  7. Summary of three dimensional pump testing of a fractured rock aquifer in the western Siberian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, R.L.; Looney, B.B.; Eddy-Dilek, C.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Drozhko, E.G.; Glalolenko, Y.V.; Mokrov, Y.G.; Ivanov, I.A. [P.A. Mayak, Chelyabinsk (Russian Federation); Glagolev, A.V.; Vasil`kova, N.A. [P.S.A. Hydrospetzgeologiya, Moscow (Russian Federation)

    1996-10-30

    A group of scientists from the Savannah River Technology Center and Russia successfully completed a 17 day field investigation of a fractured rock aquifer at the MAYAK PA nuclear production facility in Russia. The test site is located in the western Siberian Basin near the floodplain of the Mishelyak river. The fractured rock aquifer is composed of orphyrites, tuff, tuffbreccia and lava and is overlain by 0.5--12 meters of elluvial and alluvial sediments. A network of 3 uncased wells (176, 1/96, and 2/96) was used to conduct the tests. Wells 176 and 2/96 were used as observation wells and the centrally located well 1/96 was used as the pumping well. Six packers were installed and inflated in each of the observation wells at a depth of up to 85 meters. The use of 6 packers in each well resulted in isolating 7 zones for monitoring. The packers were inflated to different pressures to accommodate the increasing hydrostatic pressure. A straddle packer assembly was installed in the pumping well to allow testing of each of the individual zones isolated in the observation wells. A constant rate pumping test was run on each of the 7 zones. The results of the pumping tests are included in Appendix A. The test provided new information about the nature of the fractured rock aquifers in the vicinity of the Mishelyak river and will be key information in understanding the behavior of contaminants originating from process wastes discharged to Lake Karachi. Results from the tests will be analyzed to determine the hydraulic properties of different zones within the fractured rock aquifer and to determine the most cost effective clean-up approach for the site.

  8. Real-time weather forecasting in the Western Mediterranean Basin: An application of the RAMS model

    Science.gov (United States)

    Gómez, I.; Caselles, V.; Estrela, M. J.

    2014-03-01

    A regional forecasting system based on the Regional Atmospheric Modeling System (RAMS) is being run at the CEAM Foundation. The model is started twice daily with a forecast range of 72 h. For the period June 2007 to August 2010 the verification of the model has been done using a series of automatic meteorological stations from the CEAM network and located within the Valencia Region (Western Mediterranean Basin). Air temperature, relative humidity and wind speed and direction of the output of the model have been compared with observations. For these variables, an operational verification has been performed by computing different statistical scores for 18 weather stations. This verification process has been carried out for each season of the year separately. As a result, it has been revealed that the model presents significant differences in the forecast of the meteorological variables analysed throughout the year. Moreover, due to the physical complexity of the area of study, the model presents different degree of accuracy between coastal and inland stations. Precipitation has also been verified by means of yes/no contingency tables as well as scatter plots. These tables have been built using 4 specific thresholds that have permitted to compute some categorical statistics. From the results found, it is shown that the precipitation forecast in the area of study is in general over-predicted, but with marked differences between the seasons of the year. Finally, dividing the available data by season of the year, has permitted us to analyze differences in the observed patterns for the magnitudes mentioned above. These results have been used to better understand the behavior of the RAMS model within the Valencia Region.

  9. Exceptionally Preserved Caddisfly Larval Cases (Insecta) from the Lower Cretaceous of the Liupanshan Basin, Western China

    Institute of Scientific and Technical Information of China (English)

    Xin He; Zhong-Qiang Chen; Zongsheng Lu; Jun Li; Wei Hu; Shengfu Li; Zhitao Xu

    2015-01-01

    Abundant well-preserved tubular fossils of caddisfly (Insecta: Trichoptera) larval cases are reported from the Early Cretaceous Madongshan and Naijiahe formations of the Liupanshan Basin, Ningxia Province, western China. Most cases were mainly preserved in life position and densely packed in various layers. Individual cases in each layer tended to be same in size and were erect and parallel to one another and open at both ends. In a transverse section cut perpendicular to the long axis of the cases, individual case appears to form a rounded ring. Small cases are elliptic in a cross-section oblique to the long axis of the cases. Tube walls are nearly subparallel to one another in longitudinal section with both ends being open. The caudal end of the case slightly tapers and usually points downward. The cases were closely packed, almost touching with one another and lacking bifurcate or connecting struc-ture. The overwhelming majority of cases were partially or fully filled with calcite. The case wall em-braces a medium particle layer flanked by inner and outer organic layers. Individual particles are ovate in outline and comprise cryptocrystalline or ganic pellets. SEM imaging shows that those pellets are sub-cylindrical in outline and elliptic in cross section, and are made primarily of calcium carbonate. All features observed justify the assignment of the Liupanshan caddisfly cases to ichnogenus Coprindusia. The extinct insect Ningxiapsyche fangi was found in association with the Liupanshan caddisfly larval cases, and thus could be the candidate of the potential trace-maker.

  10. Study on relationship between deep and shallow structures along north boundary fault of Yanqing-Fanshan basin

    Institute of Scientific and Technical Information of China (English)

    于贵华; 徐锡伟; 朱艾澜; 马文涛; 刁桂苓; 张四昌; 张先康; 刘保金; 孙振国

    2004-01-01

    Based on the results of surface geology, shallow and deep seismic survey, features of micro-earthquake activity along the north boundary fault of Yanqing-Fanshan sub-basin and their relationship with the surface active faults and the deep-seated crustal structure are analyzed using the recordings from the high-resolution digital seismic network. The focal mechanism solutions of micro-earthquakes, whose locations are precisely determined by the seismic network, have confirmed the structural characteristics to be the rotational planar normal fault and demonstrated the surface traces of the north boundary fault of Yanqing-Fanshan sub-basin. By using the digital recordings of earthquakes with the high resolutions and analyzing the mechanism solutions, our study has revealed the relationship between the geological phenomena in the shallow and deep structures in Yanqing-Huailai basin and the transition features from the brittle to ductile deformation with the crustal depth.

  11. Integrating geologic and satellite radar data for mapping dome-and-basin patterns in the In Ouzzal Terrane, Western Hoggar, Algeria

    Science.gov (United States)

    Deroin, Jean-Paul; Djemai, Safouane; Bendaoud, Abderrahmane; Brahmi, Boualem; Ouzegane, Khadidja; Kienast, Jean-Robert

    2014-11-01

    The In Ouzzal Terrane (IOT) located in the north-western part of the Tuareg Shield forms an elongated N-S trending block, more than 400 km long and 80 km wide. It involves an Archaean crust remobilized during a very high-temperature metamorphic event related to the Palaeoproterozoic orogeny. The IOT largely crops out in the rocky and sandy desert of Western Hoggar. It corresponds mainly to a flat area with some reliefs composed of Late Panafrican granites, dyke networks or Cambrian volcanic rocks. These flat areas are generally covered by thin sand veneers. They are favorable for discriminating bedrock geological units using imaging radar, backscattering measurements, and field checking, because the stony desert is particularly sensitive to the radar parameters such as wavelength or polarization. The main radar data used are those obtained with the ALOS-PALSAR sensor (L-band), in ScanSAR mode (large swath) and Fine Beam modes. The PALSAR sensor has been also compared to ENVISAT-ASAR and to optical imagery. Detailed mapping of some key areas indicates extensive Archaean dome-and-basin patterns. In certain parts, the supracrustal synforms and orthogneiss domes exhibit linear or circular features corresponding to shear zones or rolling structures, respectively. The geological mapping of these dome-and-basin structures, and more generally of the Archaean and Proterozoic lithological units, is more accurate with the SAR imagery, particularly when using the L-band, than with the optical imagery. A quantitative approach is carried out in order to estimate the backscatter properties of the main rock types. Due to the large variety of configurations, radar satellite imagery such as ALOS PALSAR represents a key tool for geological mapping in arid region at different scales from the largest (e.g., 1:500,000) to the smallest (e.g., 1:50,000).

  12. Revision of the biostratigraphy of the Chatham Group (Upper Triassic), Deep River basin, North Carolina, USA

    Science.gov (United States)

    Litwin, R.J.; Ash, S.R.

    1993-01-01

    Paleontological evidence from the Upper Triassic Chatham Group in the three subbasins of the Deep River basin (North Carolina, USA) supports a significant revision of the ages assigned to most of this non-marine continental sedimentary sequence. This study confirms an early(?) or mid-Carnian age in the Sanford subbasin for the base of the Pekin Formation, the lowest unit of the Chatham Group. However, diagnostic late Carnian palynomorphs have been recovered from coals in the lower part of the Cumnock Formation in the Sanford subbasin, and from a sample of the Cumnock Formation equivalent in the Wadesboro subbasin. Plant megafossils and fossil verebrates from rocks in the Sanford subbasin also support a late Carnian age for the Cumnock Formation and its equivalents. The overlying Sanford Formation, which has not yet been dated paleontologically, probably includes beds of Norian age, as over 1000 m of strata may be present between the Cumnock Formation coals (dated here as late Carnian) and the top of the Sanford Formation. This chronostratigraphic interval appears similar to, but slightly longer than, that preserved in the Dan River-Danville and Davie County basins 100 km to the northwest. Our evidence, therefore, indicates that the Chatham Group was deposited over a much longer time interval [early(?) to mid-Carnian through early Norian] than previously was believed. ?? 1993.

  13. Early middle Miocene tectonic uplift of the northwestern part of the Qinghai–Tibetan Plateau evidenced by geochemical and mineralogical records in the western Tarim Basin

    NARCIS (Netherlands)

    Wang, Chaowen; Hong, Hanlie; Abels, Hemmo A.; Li, Zhaohui; Cao, Kai; Yin, Ke; Song, Bowen; Xu, Yadong; Ji, Junliang; Zhang, Kexin

    2016-01-01

    The Tarim Basin in western China has been receiving continuous marine to lacustrine deposits during the Cenozoic as a foreland basin of the Qinghai–Tibetan Plateau (QTP). Clay mineralogy and geochemical proxy data from these sedimentary archives can shed light on climate and tectonic trends. Here we

  14. Prevalence of iron deficiency anaemia among blood donors in Sokoto, North Western, Nigeria

    Directory of Open Access Journals (Sweden)

    Buhari Hauwa Ali

    2015-04-01

    Full Text Available Objective: To investigate the prevalence and socio-demographic factors associated with iron deficiency anaemia among blood donors in Sokoto, North Western, Nigeria using a combination of haemoglobin haematocrit and serum ferritin measurements. Methods: One hundred and fifty consecutively recruited whole blood donors, comprising of 148 (98.7% family replacement donors and 2 (1.3% voluntary non-remunerated donors aged 18-60 years and mean age 39±21 years constituted the subjects for this study. The full blood count was carried out using Mythic 22 CT fully automated haematology analyser (Orphee SA, Switzerland. Serum was tested for ferritin using a human ferritin enzyme immunoassay kitACCU Diag™ ELISA Ferritin kit (Diagnostic Automation/Cortez Diagnostic Inc. California, USA. Results: The prevalence of anaemia (haemoglobin<11.0 g/dL was evident in 24 (16% and iron deficiency anaemia (serum ferritin<12 ng/mL+haemoglobin<11 g/dL in 5 (10% of donors. The haemoglobin and ferritin levels was significantly lower among regular voluntary remunerated blood donors (13.50±0.00 and 34.88±0.00 compared to family replacement donors (14.10±2.40 and 74.12±45.20 respectively (P=0.01 and 0.05 respectively. The mean haemoglobin and ferritin level was compared among donors based on gender. The haemoglobin and ferritin was significantly higher among male donors (14.20±2.00, 78.02±49.10 compared to female donors (12.35±2.5 and 42.20±32.13 (P=0.01. The mean haemoglobin and ferritin level was compared among donors based on occupational groups. The haemoglobin and ferritin was significantly higher among civil servants compared to farmers and students (P=0.01. Conclusions: Iron deficiency anaemia is prevalent among blood donors in Sokoto, North Western, Nigeria. There is need to include routine ferritin in the blood donor testing protocol in the area to enable the diagnosis of donors with latent iron deficiency anaemia to facilitate iron supplementation for

  15. OH and HO{sub 2} measurements in a forested region of north-western Greece

    Energy Technology Data Exchange (ETDEWEB)

    Creasey, D.J.; Heard, D.E.; Lee, J.D. [Leeds Univ., School of Chemistry, Leeds (United Kingdom)

    2001-07-01

    Boundary layer concentration of hydroxyl (OH) and hydroperoxyl (HO{sub 2}) radicals were measured at 1180m elevation in a mountainous, forested region of north-western Greece during the AEROsols formation from Biogenic organic Carbon (AEROBIC) field campaign held in July-August 1997. In situ measurements of OH radicals were made by laser-induced fluorescence (LIF) at low pressure, exciting in the (0, 0) band of the A-X system at 308nm. HO{sub 2} radicals were monitored by chemical titration to OH upon the addition of NO, with subsequent detection by LIF. The instrument was calibrated regularly during the field campaign, and demonstrated a sensitivity towards OH and HO{sub 2} of 5.2x10{sup 5} and 2.4x10{sup 6}moleculecm{sup -3}, respectively, for a signal integration period of 2.5min and a signal-to-noise ratio of 1. Diurnal cycles of OH and HO{sub 2} were measured on 10 days within a small clearing of a forest of Greek Fir (Abies Borisi-Regis). In total 4165 OH data points and 1501 HO{sub 2} data points were collected at 30s intervals. Noon-time OH and HO{sub 2} concentrations were between 4-12x10{sup 6} and 0.4-9x10{sup 8}moleculecm{sup -3}, respectively. The performance of the instrument is evaluated, and the data are interpreted in terms of correlations with controlling variables. A significant correlation (r{sup 2}=0.66) is observed between the OH concentration and the rate of photolysis of ozone, J(O{sup 1}D). However, OH persisted into the early evening when J(O{sup 1}D) had fallen to very low values, consistent with the modelling study presented in the following paper (Carslaw et al., 2001, OH and HO{sub 2} radical chemistry in a forest region of north-western Greece. Atmospheric Environment 35, 4725-4737) that predicts a significant radical source from the ozonolysis of biogenic alkenes. Normalisation of the OH concentrations for variations in J(O{sup 1}D) revealed a bell-shaped dependence of OH upon NO{sub x} (NO+NO{sub 2}), which peaked at [NO{sub x

  16. Four years' observations of terrestrial lipid class compounds in marine aerosols from the western North Pacific

    Science.gov (United States)

    Kawamura, K.; Ishimura, Y.; Yamazaki, K.

    2003-03-01

    In order to understand the long-range atmospheric transport of terrestrial organic matter over the open ocean, marine aerosol samples were collected on a biweekly basis from 1990 to 1993 in a remote island, Chichi-Jima, in the western North Pacific. The samples were analyzed for lipid class compounds using a capillary gas chromatography (GC) and GC/mass spectrometry (GC/MS). A homologous series of n-alkanes (C20-C40), alcohols (C13-C34), fatty acids (C9-C34) and α,ω-dicarboxylic acids (C7-C28) were detected in the aerosol samples. Distributions of n-alkanes (0.17-14 ngm-3, average 1.7 ngm-3) are characterized by a strong odd-carbon number predominance (CPI ratios, average 4.5) with a maximum at C29 or C31, indicating that n-alkanes are mainly derived from terrestrial higher plant waxes. Fatty alcohols (0.19-23 ngm-3, average 2.0 ngm-3) show an even-carbon number predominance with a maximum generally at C26 or C28, again indicating a contribution from terrestrial higher plants. On the other hand, fatty acids (2.5-38 ngm-3, average 14 ngm-3) show a bimodal distribution with two maxima at C16 and C24 or C28. Lower molecular weight fatty acids (generally fatty acids (C21-C34) derived from terrestrial higher plants, together with C25-C35 alkanes, C20-C34 alcohols and C20-C28 dicarboxylic acids, generally showed higher concentrations in winter to spring seasons. This seasonal trend is most likely interpreted as atmospheric transport of terrestrial organic matter from Asian continent in winter/spring, when westerly winds dominate over the western North Pacific. Backward trajectory analyses supported the long-range atmospheric transport of higher plant- and soil-derived organic matter from the Asian continent over the Pacific Ocean. This study also suggested that the atmospheric transport is the main pathway for the terrestrial lipid compounds that are abundantly present in the deep-sea sediments in the Central Pacific.

  17. Long-term changes of glaciers in north-western Spitsbergen

    Science.gov (United States)

    Sobota, Ireneusz; Nowak, Marcin; Weckwerth, Piotr

    2016-09-01

    This paper comprises a detailed description of glaciers of the Kaffiøyra region, an area of Svalbard, located in north-western Spitsbergen. The primary objective of this work is to present the essential conditions and characteristics of changes in the dynamics and spatial extent of the glaciers in that region. Most of the research consisted in direct field measurements carried out in 1996-2015, and the investigated changes were mainly related to the mass balance on the Waldemarbreen, the Irenebreen and the Elisebreen. In order to identify the changes of the glaciated area of the studied region, a detailed analysis of the degree of changes in the glaciers' surface area and recession was carried out, starting with the period of their maximum extent in the late 19th and early 20th centuries, i.e. by the end of the Little Ice Age. Statistical analysis of measurement data from 1970 to 2015 enabled the development of a simple empirical formula used to work out the mass balance with a similar accuracy to that achieved using direct methods. The mean annual mass balance of the three analysed glaciers was: ˗0.72 m w.e. in the case of the Waldemarbreen in 1996-2015, - 0.84 m w.e. in the case of the Irenebreen in 2002-2015, and - 0.65 m w.e. in the case of the Elisebreen in 2006-2013. For the Waldemarbreen the change of mass balance with time was estimated to be - 0.040 (± 0.003) m w.e. a- 1. In the same period for the Irenebreen it was - 0.052 (± 0.024) m w.e. a- 1. From the time of their maximum reach in the late 19th and early 20th centuries to 2015, the total area of the Kaffiøyra region valley glaciers decreased by about 43.0% on average. Glaciers in the region retreated at an average rate of 12 ma- 1. The changes of the glaciers' front positions, which make the north-western coast of Spitsbergen, are similar to the changes observed for other Svalbard glaciers of this type. The investigations of the glacier mass balance in the Kaffiøyra region are especially

  18. Skill of western North Pacific tropical cyclone intensity forecast guidance relative to Weighted-Analog technique

    Science.gov (United States)

    Tsai, Hsiao-Chung; Elsberry, Russell L.

    2016-06-01

    The accuracy of the western North Pacific tropical cyclone intensity forecast guidance products available at the Joint Typhoon Warning Center (JTWC) is evaluated relative to a new skill metric called Weighted Analog Intensity Pacific (WAIP) that includes knowledge of the JTWC official track forecast and the current intensity, which is information that is available at the time the intensity forecast is generated. An intensity consensus technique called S5XX that includes statistical-dynamic intensity forecasts plus other dynamic and thermodynamic prediction techniques has statistically significant smaller errors than WAIP at 24 h and 48 h and has similar accuracy through 120 h. While the track consensus CONW is a critical input to the JTWC official track forecast, it has no skill relative to WAIP as an intensity forecast. Three regional numerical models also have no skill relative to WAIP, and especially at forecast intervals beyond 72 h because their mean absolute errors are statistically significantly larger than for WAIP. Furthermore, these regional models have statistically significant positive or negative intensity biases relative to the verifying intensities. However, an experimental consensus technique called CMES that includes these three regional models has small accuracy relative to WAIP in the 24 h to 72 h forecast intervals. Geographical-based comparisons of the intensity guidance products with the WAIP indicate almost all of the products are more accurate than WAIP over the South China Sea region. The statistical-dynamic consensus technique S5XX does have skill through 72 h for landfalling situations along the coasts of China and Southeast Asia. At 120 h, the WAIP has superior performance over the guidance products over most areas of the western North Pacific, but again the S5XX is more accurate than WAIP for landfalling tropical cyclones on the Philippine Islands, Southeast Asia, South China, and northeastern Japan. This information will be useful to

  19. Prevalence of iron deficiency anaemia among blood donors in Sokoto, North Western, Nigeria

    Institute of Scientific and Technical Information of China (English)

    Buhari Hauwa Ali; Yeldu Mohammed Haruna; Erhabor Osaro; Imrana Sani; Abubakar Wase; Onuigwe Festus; Okwesili Augustine; Isaac Zama; Yakubu Abdulrahaman; Dallatu Kabiru

    2015-01-01

    Objective: To investigate the prevalence and socio-demographic factors associated with iron deficiency anaemia among blood donors in Sokoto, North Western, Nigeria using a combination of haemoglobin haematocrit and serum ferritin measurements. Methods: One hundred and fifty consecutively recruited whole blood donors, comprising of 148 (98.7%) family replacement donors and 2 (1.3%) voluntary non-remunerated donors aged 18-60 years and mean age 39±21 years constituted the subjects for this study. The full blood count was carried out using Mythic 22 CT fully automated haematology analyser (Orphee SA, Switzerland). Serum was tested for ferritin using a human ferritin enzyme immunoassay kit-ACCU Diag™ ELISA Ferritin kit (Diagnostic Automation/Cortez Diagnostic Inc. California, USA). Results: The prevalence of anaemia (haemoglobin<11.0 g/dL) was evident in 24 (16%) and iron deficiency anaemia (serum ferritin<12 ng/mL+haemoglobin<11 g/dL) in 5 (10%) of donors. The haemoglobin and ferritin levels was significantly lower among regular voluntary remunerated blood donors (13.50±0.00 and 34.88±0.00) compared to family replacement donors (14.10±2.40 and 74.12±45.20) respectively (P=0.01 and 0.05 respectively). The mean haemoglobin and ferritin level was compared among donors based on gender. The haemoglobin and ferritin was significantly higher among male donors (14.20±2.00, 78.02±49.10) compared to female donors (12.35±2.5 and 42.20±32.13) (P=0.01). The mean haemoglobin and ferritin level was compared among donors based on occupational groups. The haemoglobin and ferritin was significantly higher among civil servants compared to farmers and students (P=0.01). Conclusions: Iron deficiency anaemia is prevalent among blood donors in Sokoto, North Western, Nigeria. There is need to include routine ferritin in the blood donor testing protocol in the area to enable the diagnosis of donors with latent iron deficiency anaemia to facilitate iron supplementation for regular

  20. Organic Carbon Geochemistry in the North-western Black Sea Danube River System

    Science.gov (United States)

    Galimov, E. M.; Kodina, L. A.; Zhiltsova, L. I.; Tokarev, V. G.; Vlasova, L. N.; Bogacheva, M. P.; Korobeinik, G. S.; Vaisman, T. I.

    2002-03-01

    The isotopic and chemical composition of organic matter from sediments collected on the north-western shelf of the Black Sea and the Danube River are discussed. The δ 13C distribution pattern in organic carbon from surface sediments (0-1 cm) of the western part of the Black Sea has been established. It reveals a rather complicated picture, reflecting the superposition of several factors: local marine primary productivity, terrestrial input to the Danube River discharge and possible contribution from anaerobic microbial activity. The analysis of organic carbon by a pyrolysis-chromatography technique showed that the H/O indices of organic matter from marine sediments are in correlation with δ 13C values. This is an indication of the mixed origin of the organic carbon in the littoral sediments. However, samples from the zone where H 2S conditions prevail deviate from the correlation line of δ 13C vs H/O indices. We believe that this is due to the contribution of the biomass of chemosynthetic bacteria in the sediments. Thus, we argue that in the Danube-Black Sea system several consecutive zones are distinguished. River discharge delivers organic carbon with δ 13C values from -28 to -26 (PSU is used). Mixing of the land-derived material with autochtonous marine primary production gives δ 13C values of about -26 to -23 for the organic carbon in coastal sediments. On the shelf area, beyond significant influence of both terrestrial and sulphide regime factors, plankton material dominates as a source of organic carbon in sediments. In the hydrogen sulphide zone, chemosynthetic bacteria produce additional amounts of organic matter with hydrogen to oxygen indices similar to those of plankton, but with different isotopic composition, which results in the appearance of relatively isotopically light organic carbon in the deep-sea sediments.

  1. Supercritical Submarine Channel Morphodynamics from Integrated Investigation of the Western North American Continental Margin

    Science.gov (United States)

    Covault, J. A.; Fildani, A.; Hubbard, S. M.; Hughes Clarke, J. E.; Kostic, S.; Paull, C. K.; Sylvester, Z.

    2015-12-01

    Submarine channels are conduits through which turbidity currents and related mass movements transport sediment into the deep sea, thereby playing important roles in the development of continental margins and biogeochemical cycles. To gain a better understanding of submarine channel morphodynamic evolution we explore a variety of channel systems from the western North American continental margin with varying sinuosity and levee geometry, terraces, channel cut-offs, and sediment waves in incipient channels, along thalwegs of well-developed channels, and on levees. Repeat bathymetric surveys of submarine channels in fjords of British Columbia and the Monterey canyon underscore the transience of fine-scale detail in channelized geomorphology, and multi-phase bed reworking, local deposition, and bypass of turbidity currents. Numerical modeling is combined with interpretations of channel geomorphology and strata in the Monterey and San Mateo canyon-channel systems to demonstrate that some of the sediment waves are likely to be cyclic steps. Submarine cyclic steps are long-wave, upstream-migrating bedforms in which each bedform in the series is bounded by a hydraulic jump in an overriding turbidity current, which is Froude-supercritical over the lee side of the bedform and Froude-subcritical over the stoss side. Submarine turbidity currents are susceptible to supercritical flow because of the reduced gravitational acceleration of dilute suspensions. Higher submarine slopes common to the North American continental margin also promote supercritical flow, which might not be as common across lower slopes of large passive margins such as the Amazon, Indus, and Bengal submarine fans. We posit that cyclic steps are a common morphodynamic expression in many continental margins. Continued integration of high-resolution data, such as repeat geophysical surveys, acoustic doppler current profiler measurements, and turbidite outcrops, which provide insights into the longer

  2. Hydrography and biogeochemistry of the north western Bay of Bengal and the north eastern Arabian Sea during winter monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Balachandran, K.K.; Laluraj, C.M.; Jyothibabu, R.; Madhu, N.V.; Muraleedharan, K.R.; Vijay, J.G.; Maheswaran, P.A.; Ashraf, T.T.M.; Nair, K.K.C.; Achuthankutty, C.T.

    to respond paradoxically to comparable intensities of the atmospheric forcing. There is an asymmetry in the net heat exchange of these two basins with atmosphere because of the varying thickness of barrier layer. During winter, the convective mixing...

  3. Hydrocarbon prospectivity in Western Greece

    Energy Technology Data Exchange (ETDEWEB)

    Maravelis, Angelos; Makrodimitras, George; Zelilidis, Avraam [Patras Univ. (Greece). Lab. of Sedimentology

    2012-06-15

    The geology of Western Greece is dominated by the most external zones of the Hellenide fold-and-thrust belt, namely the Pre-Apulian (or Paxoi) and Ionian zones. With Western Greece and Albania having undergone, in broad terms, similar geological histories, also the hydrocarbon potentials of both areas may be compared. Likewise, the hydrocarbon potential of Italy's Apulian Platform, adjoining in the westerly offshore, may serve as an analogue. Three basin types within Western Greece that deserve hydrocarbon exploration have been examined and are grouped, correlated to major tectonic features, namely foreland (Ionian thrusts' foreland basin), piggy-back (Ionian thrusts' back-arc basin) and strike-slip basins. Additionally, strike-slip basins are further subdivided into the basin north of the Borsh-Khardhiqit strike-slip fault and the Preveza basin, north of Cephalonia transfer fault. Their filling histories suggest the occurrence of Mesozoic carbonate plays and Oligocene/Miocene sandstone plays both for oil and gas.

  4. An Overview of the DAURE Campaign: Aerosols Emissions and Evolution in the Western Mediterranean Basin

    Science.gov (United States)

    Pandolfi, Marco; Querol, Xavier; Alastuey, Andrés.; Jimenez, Jose L.

    2010-05-01

    DAURE (Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in the western Mediterranean) is a multidisciplinary international measurement campaign mainly aimed at estimating the sources and origin of atmospheric fine aerosols in the Western Mediterranean Basin (WMB), with particular attention to the carbonaceous fraction. Main focuses of the campaign are the study of the origin of the intense pollution episodes frequently occurring at regional scale in summer and winter in the WMB (Perez et al., 2008) and the emission, formation, transport and transformation of aerosols during these polluted scenarios. The peculiar atmospheric dynamics in the WMB, regulated by complex climatic and orographic effects (Millán et al., 1997), together with the large pollutant emissions from densely populated areas, large industrial areas and ports located along the coastline, give rise to a complex phenomenology for aerosol formation and transformation. In this context, extremely high concentrations of fine particulate matter (mainly PM1, particulate matter with aerodynamic diameter MAAP, CPC, SMPS, Rotating Drum Impactor, among others) and remote sensing techniques (LIDAR, sunphotometer) have been applied together with state-of-the-art methods such as 14C (Szidat et al., 2006), Proton-Transfer Reaction Mass Spectrometry (PTRMS) for VOCs, and High-Resolution Aerosol Mass Spectrometer (AMS) (DeCarlo et al., 2006). These state-of-the-art techniques have been applied for the first time in the Western Mediterranean region within DAURE. Particular attention was devoted to quantitatively understand the sources and formation mechanisms of secondary inorganic and organic aerosols (SIA and SOA) in the WMB and the effects caused by anthropogenic activities in SOA formation at local and regional level. Here we give an overview of the objective of the DAURE campaign, groups involved and measurements performed. The main results of the DAURE winter and summer

  5. A new species of Ischyodus (Chondrichthyes: Holocephali: Callorhynchidae) from Upper Maastrichtian Shallow marine facies of the Fox Hills and Hell Creek Formations, Williston basin, North Dakota, USA

    Science.gov (United States)

    Hoganson, J.W.; Erickson, J.M.

    2005-01-01

    A new species of chimaeroid, Ischyodus rayhaasi sp. nov., is described based primarily upon the number and configuration of tritors on palatine and mandibular tooth plates. This new species is named in honour of Mr Raymond Haas. Fossils of I. rayhaasi have been recovered from the Upper Maastrichtian Fox Hills Formation and the Breien Member and an unnamed member of the Hell Creek Formation at sites in south-central North Dakota and north-central South Dakota, USA. Ischyodus rayhaasi inhabited shallow marine waters in the central part of the Western Interior Seaway during the latest Cretaceous. Apparently it was also present in similar habitats at that time in the Volga region of Russia. Ischyodus rayhaasi is the youngest Cretaceous species Ischyodus known to exist before the Cretaceous/Tertiary extinction, and the species apparently did not survive that event. It was replaced by Ischyodus dolloi, which is found in the Paleocene Cannonball Formation of the Williston Basin region of North Dakota and is widely distributed elsewhere. ?? The Palaeontological Association.

  6. SOME TRADITIONAL HEALTH CARE PRACTICES OF JAUNDICE IN PARTS OF WESTERN ASSAM (NORTH EAST INDIA

    Directory of Open Access Journals (Sweden)

    N.Nath

    2013-12-01

    Full Text Available The very old traditional Indian herbal medicinal heritage flow in two streams –one is codified classical stream and the other one is the non-codified or the oral folk .The codified system is more institutionalized and is basically of four types - Ayurveda, Sidha, Unani and Gsorigpa.It is interesting that the non- codified systems are more popularly known as Local Health Tradition (LHT though it is informal it exists among various ethnic and traditional communities of India more particularly in North East India of which the study area i. e. Western Assam being a part is found to be rich in such traditional herbal system of health care practices. Western Assam is located at the extreme western part of Assam it extends from 89049/20// E longitude to 91048/16// longitude and 25027/ N latitude to 26054// latitude covering lower Brahmaputra valley. For primary data collection the fields were visited frequently meeting the local people specially these people who are well experienced with the knowledge of local health practices through interview during 2012- 2013. During data collection it was found that there are many knowledgeable persons in the field of herbal health care practices who often practice their medicinal systems to cure various types of diseases like piles, fever ,stomach disorder, eye problem, bone problem including some minor bodily disorders .But in this paper importance is given to one of the very dangerous more common disease that is Jaundice which is caused by an excess of a waste product bilirubin in blood after the removal of iron from hemoglobin ;this excess bilirubin may leak out into surrounding tissues saturating them with this yellow substance. Here 5 main herbal recipes are analyzed and presented in a very lucid scientific way. Thus the herbal preparations presented here practiced by various knowledgeable persons in herbal medicines (known as Ojha, Kobiraj, Bej, Healers etc. which are often found very active preparations

  7. Possible influence of western North Pacific monsoon on TC activity in mid-latitudes of East Asia

    Science.gov (United States)

    Choi, Ki-Seon; Cha, Yumi; Kim, Hae-Dong; Kang, Sung-Dae

    2016-01-01

    This study analyzed the correlation between tropical cyclone (TC) frequency and the Western North Pacific monsoon index (WNPMI), which have both been influential in East Asia's mid-latitude regions during the summer season over the past 37 years (1977-2013). A high positive correlation existed between these two variables, which was not reduced even if El Niño-Southern Oscillation (ENSO) years were excluded. To determine the cause of this positive correlation, the highest (positive WNPMI phase) and lowest WNPMIs (negative WNPMI phase) during a nine-year period were selected to analyze the mean difference between them, excluding ENSO years. In the positive WNPMI phase, TCs were mainly generated in the eastern seas of the tropical and subtropical western North Pacific, passing through the East China Sea and moving northward toward Korea and Japan. In the negative phase, TCs were mainly generated in the western seas of the tropical and subtropical western North Pacific, passing through the South China Sea and moving westward toward China's southern regions. Therefore, TC intensity in the positive phase was stronger due to the acquisition of sufficient energy from the sea while moving a long distance up to East Asia's mid-latitude. Additionally, TCs occurred more in the positive phase. Regarding the difference of the two phases between the 850 and 500-hPa streamlines, anomalous cyclones were strengthened in the tropical and subtropical western North Pacific, whereas anomalous anticyclones were strengthened in East Asia's mid-latitude regions. Due to these two anomalous pressure systems, anomalous southeasterlies developed in East Asia's mid-latitude regions, which played a role in the anomalous steering flows that moved TCs into these regions. Furthermore, due to the anomalous cyclones that developed in the tropical and subtropical western North Pacific, more TCs could be generated in the positive phase. Both the lower and upper tropospheric layers had warm anomalies

  8. Response of a dryland fluvial system to climate-tectonic perturbations during the Late Quaternary: Evidence from Rukmawati River basin, Kachchh, western India

    Science.gov (United States)

    Das, Archana; Bhattacharya, Falguni; Rastogi, B. K.; Chauhan, Gaurav; Ngangom, Mamata; Thakkar, M. G.

    2016-08-01

    Dryland rivers, dominated by short-lived, localised and highly variable flow due to discrete precipitation events, have characteristic preservation potential, which serves as suitable archives towards understanding the climate-tectonic coupling. In the present study, we have investigated the fluvial records of a major, southerly-draining river - the Rukmawati River in the dryland terrain of southern Kachchh, in western India. The sediment records along the bedrock rivers of Kachchh register imprints of the Indian summer monsoon (ISM), which is the major source of moisture to the fluvial system in western India. The Rukmawati River originates from the Katrol Hill Range in the north and flows towards the south, into the Gulf of Kachchh. The field stratigraphy, sedimentology, along with the optical chronology suggests that a braided-meandering system existed during 37 ka period due to an overall strengthened monsoon. A gradual decline in the monsoon strength with fluctuation facilitated the development of a braided channel system between 20 and 15 ka. A renewed phase of strengthened monsoon with seasonality after around 15 ka which persisted until around 11 ka, is implicated in the development of floodplain sequences. Two zones of relatively high bedrock uplift are identified based on the geomorphometry and morphology of the fluvial landform. These zones are located in the vicinity of the North Katrol Hill Fault (NKHF) and South Katrol Hill Fault (SKHF). Geomorphic expression of high bedrock uplift is manifested by the development of beveled bedrock prior to or around 20 ka during weak monsoon. The study suggests that the terrain in the vicinity of NKHF and SKHF is uplifting at around 0.8 and >0.3 mm/a, respectively. Simultaneously, the incision in the Rukmawati River basin, post 11 ka, is ascribed to have occurred due to lowered sea level during the LGM and early Holocene period.

  9. Response of a dryland fluvial system to climate–tectonic perturbations during the Late Quaternary: Evidence from Rukmawati River basin, Kachchh, western India

    Indian Academy of Sciences (India)

    Archana Das; Falguni Bhattacharya; B K Rastogi; Gaurav Chauhan; Mamata Ngangom; M G Thakkar

    2016-08-01

    Dryland rivers, dominated by short-lived, localised and highly variable flow due to discrete precipitation events, have characteristic preservation potential, which serves as suitable archives towards understanding the climate–tectonic coupling. In the present study, we have investigated the fluvial records of a major, southerly-draining river – the Rukmawati River in the dryland terrain of southern Kachchh, in western India. The sediment records along the bedrock rivers of Kachchh register imprints of the Indian summer monsoon (ISM), which is the major source of moisture to the fluvial system in western India. The Rukmawati River originates from the Katrol Hill Range in the north and flows towards the south, into the Gulf of Kachchh. The field stratigraphy, sedimentology, along with the optical chronology suggeststhat a braided-meandering system existed during 37 ka period due to an overall strengthened monsoon. A gradual decline in the monsoon strength with fluctuation facilitated the development of a braided channel system between 20 and 15 ka. A renewed phase of strengthened monsoon with seasonality after around 15 ka which persisted until around 11 ka, is implicated in the development of floodplain sequences. Two zones of relatively high bedrock uplift are identified based on the geomorphometry and morphology of the fluvial landform. These zones are located in the vicinity of the North Katrol Hill Fault (NKHF) and South Katrol Hill Fault (SKHF). Geomorphic expression of high bedrock uplift is manifested by the development of beveled bedrock prior to or around 20 ka during weak monsoon. The study suggests that the terrain in the vicinity of NKHF and SKHF is uplifting at around 0.8 and >0.3 mm/a, respectively. Simultaneously, the incision in the Rukmawati River basin, post 11 ka, is ascribed to have occurred due to lowered sea level during the LGM and early Holocene period.

  10. Megascopic lithologic studies of coals in the Powder River basin in Wyoming and in adjacent basins in Wyoming and North Dakota

    Science.gov (United States)

    Trippi, Michael H.; Stricker, Gary D.; Flores, Romeo M.; Stanton, Ronald W.; Chiehowsky, Lora A.; Moore, Timothy A.

    2010-01-01

    Between 1999 and 2007, the U.S. Geological Survey (USGS) investigated coalbed methane (CBM) resources in the Wyoming portion of the Powder River Basin. The study also included the CBM resources in the North Dakota portion of the Williston Basin of North Dakota and the Wyoming portion of the Green River Basin of Wyoming. This project involved the cooperation of the State Office, Reservoir Management Group (RMG) of the Bureau of Land Management (BLM) in Casper, Wyo., and 16 independent gas operators in the Powder River, Williston, and Green River Basins. The USGS and BLM entered into agreements with these CBM operators to supply samples for the USGS to analyze and provide the RMG with rapid, timely results of total gas desorbed, coal quality, and high-pressure methane adsorption isotherm data. This program resulted in the collection of 963 cored coal samples from 37 core holes. This report presents megascopic lithologic descriptive data collected from canister samples extracted from the 37 wells cored for this project.

  11. Messinian erosional and salinity crises: View from the Provence Basin (Gulf of Lions, Western Mediterranean)

    OpenAIRE

    Bache, François; Olivet, Jean-Louis; Gorini, Christian; Rabineau, Marina; Baztan, J.; Aslanian, Daniel; Suc, Jean-Pierre

    2009-01-01

    International audience Though the late Miocene “Messinian Salinity Crisis” has been intensely researched along the circum-Mediterranean basins, few studies have focused on the central part of the Mediterranean Basin and, especially, the pre-salt deposits. To improve our knowledge of the Messinian events, it is imperative to better understand this domain. In this study, we provide a more complete understanding of this central domain in the Provence Basin. We were able to recognize: a) thick...

  12. Watcr Security Situation in Haihc Rivcr Basin after South-to-North Watcr Transfer Project

    Institute of Scientific and Technical Information of China (English)

    JIA Shaofeng; YAN Tingting; LUE Aifeng

    2012-01-01

    The over-exploitation of water resources in the Haihe River Basin (HRB) has now become a serious problem. This is clearly evidenced by the fact that many local rivers and lakes are drying up and the total amount of over-exploited groundwater has reached over 1000×10^8m^3. It is important to note that the exploitation of water resources in HRB was reasonable before 1979. After 1980, however, over-exploitation happened with an annual average amount of 40×10^8m^3. Both the dry season and rapid economic growth in HRB took place at the same time. Therefore, the over-exploitation of water in HRB was actually the negative result of the conjunction of a continuous dry season and rapid economic growth. So the over-exploitation would not be as serious as it is today if either of the above two stopped. After the first stage of south-to-north water transfer project, the water shortage problem in HRB could be eased for the following reasons: firstly, water transfer project will bring to the Basin 60x108m3 water resources; secondly, a wet season will come back eventually according to natural law of climate variability; finally, its agricultural and industrial use and total water consumption all have decreased from the peak value, so that the groundwater table will raise certainly and ecological water in rivers and lakes that were dried-up will be partly restored. In the future, the main problem of water resources security in HRB will include water pollution, operation risk of the south-to-north water transfer project, groundwater pollution and engineering geological hazards that may be brought by groundwater rise. The proposed countermeasures are as follows: keeping strengthening water demand management, raising water price as well as subsidies for the low- income family and improving other water related policies, preventing and dealing with water pollution seriously and getting fully prepared for the operation of south-to-north water transfer project.

  13. Modeling petroleum generation and accumulation in Qarun field, north Western Desert, Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Younes, Mohamed Abdel-Aziz [Alexandria Univ. (Egypt). Dept. Geology

    2011-09-15

    The Qarun area lies on the southeast flank of the Jurassic-Cretaceous Kattaniya uplift and the northwest flank of the Gindi Basin in the northernWestern Desert of Egypt, where many promising structural traps have been discovered within the inverted basin. The Rock-Eval pyrolysis technique carried out on 59 shale rock samples representing the stratigraphic succession of the well Qarun-5X revealed the presence of two excellent potential source rocks within the Khatatba and Abu Roash formations with different levels of thermal maturity. The burial history model proved that the shale rock of the Khatatba formation reached the late mature stage of oil generation at the vitrinite reflectance value of 1.35 Ro% between 100 to 80 Ma. Meanwhile, the shale rock of the Abu RoashGand F formation entered the earlymature stage of oil generation at the vitrinite reflectance value of 0.5-0.7 Ro% between 50 to 40 Ma. The geochemical fingerprints of 9 crude oil samples also support a genetic relation to multiple source rocks for oil generation. The crude oil produced from the Kharita formation has a low ratio of oleanane index <10% and high maturity level of C{sub 29}{alpha}{alpha}{alpha} Cholestane 20S/(20S+20R) ratio >0.5 and has the great affinity to be generated from shale section of the Khatatba formation that has amixed kerogen types II-III. Meanwhile, the biomarker fingerprints of crude oils produced from the Bahariya formation indicate a high oleanane index >20% and low ratios of C{sub 29}{alpha}{alpha}{alpha} Cholestane 20S/(20S+20R) <0.5. These characteristics referred their origin to the shale source rocks of the Abu Roash formation G and F which have mixed type II-III kerogen thatwere derived from amixed environment containing an admixture of continental and marginal marine organic matter and have the ability to generate mixed oil and gas accumulations under thermal maturation. The burial history modeling suggests that initial hydrocarbon expulsion from Jurassic source

  14. Urban floods: a case study in the Savigliano area (North-Western Italy

    Directory of Open Access Journals (Sweden)

    C. Audisio

    2011-11-01

    Full Text Available Flood processes and effects are examined, concerning two rivers in an urbanized area in North-Western Italy (Piedmont – Cuneo Plain. In May 2008, some areas in Northern Italy were struck by intense and persistent rainfall. In the Cuneo province (Southern Piedmont, floodplain with some urban areas was inundated over ca. ten square kilometres, and the city of Savigliano (about 21 000 inhabitants was particularly hit by flood. A purposely-made historical research has evidenced approximately fifty flood events as having occurred since 1350 in the Savigliano area. Based upon historical data, both documents and maps, GIS (Geographical Information System technique and field surveys were used to quantitatively assess the growing urbanization of the city and to describe flood processes and effects over years. This work aims to describe the dynamic behaviour of the 2008 flood, also comparing it to past events, in particular those that occurred in 1896. It is emphasized how the knowledge of past events can be helpful in reducing urban flooding.

  15. Effects of South China Sea/western North Pacific summer monsoon on tropospheric biennial oscillation (TBO)

    Institute of Scientific and Technical Information of China (English)

    Zheng Bin; Gu De-Jun; Lin Ai-Lan; Li Chun-Hui

    2007-01-01

    Severed theories have been developed to explain tropical biennial oscillation (TBO), as an air-sea interactive system to impact Asian and global weather and climate, and some models have been established to produce a TBO. A simple 5-box model, with almost all the key processes associated with TBO, can produce a TBO by including air-sea interactions in the monsoon regions. Despite that, the South China Sea/western North Pacific summer monsoon (SCS/WNPSM), a very important monsoon subsystem, is neglected. In this paper, based on the dynamical framework of 5-box model, the term of SCS/WNPSM has been added and a 6-box model has been developed. Comparing the difference of TBO sensibilities with several key parameters, air-sea coupling coefficient α, SST-thermocline feedback coefficient γ and wind-evaporation feedback coefficient λ, between the modified model and original model, TBO is more sensible to the parameters in the new model. The results imply that the eastern Pacific and local wind-evaporation play more important roles in the TBO when including SCS/WNPSM.

  16. Multiscale perspectives of fire, climate and humans in western North America and the Jemez Mountains, USA.

    Science.gov (United States)

    Swetnam, Thomas W; Farella, Joshua; Roos, Christopher I; Liebmann, Matthew J; Falk, Donald A; Allen, Craig D

    2016-06-01

    Interannual climate variations have been important drivers of wildfire occurrence in ponderosa pine forests across western North America for at least 400 years, but at finer scales of mountain ranges and landscapes human land uses sometimes over-rode climate influences. We reconstruct and analyse effects of high human population densities in forests of the Jemez Mountains, New Mexico from ca 1300 CE to Present. Prior to the 1680 Pueblo Revolt, human land uses reduced the occurrence of widespread fires while simultaneously adding more ignitions resulting in many small-extent fires. During the 18th and 19th centuries, wet/dry oscillations and their effects on fuels dynamics controlled widespread fire occurrence. In the late 19th century, intensive livestock grazing disrupted fuels continuity and fire spread and then active fire suppression maintained the absence of widespread surface fires during most of the 20th century. The abundance and continuity of fuels is the most important controlling variable in fire regimes of these semi-arid forests. Reduction of widespread fires owing to reduction of fuel continuity emerges as a hallmark of extensive human impacts on past forests and fire regimes.This article is part of the themed issue 'The interaction of fire and mankind'. PMID:27216525

  17. Bankfull Curves for the Temperate Rainforests in the Southern Appalachian Mountains of Western North Carolina

    Directory of Open Access Journals (Sweden)

    MICKEY B. HENSON

    2014-08-01

    Full Text Available Bankfull hydraulic geometry relationships, also called regional curves, relate bankfull stream channel dimensions and discharge to watershed drainage area. This paper describes results of bankfull curve relationships developed for the temperate rainforests of the Southern Appalachian Mountains primarily on Western North Carolina Mountain streams in the Southeastern United States. Gauge stations for small and larger catchments were selected with a range of 10 to 50 years of continuous or peak discharge measurements, no major impoundments, no significant change in land use over the past 10 years, and impervious cover ranges of <20%. Cross-sectional and longitudinal surveys were measured at each study reach to determine channel dimension, pattern, and profile information. Log-Pearson Type III distributions were used to analyze annual peak discharge data for nine small watersheds sites gauged by the United States Department of Agriculture (USDA, Forest Service, Southern Research Station, Coweeta Hydrologic Laboratory and for eleven larger watersheds gauged by the United States Geological Survey (USGS. Power function relationships were developed using regression analyses for bankfull discharge, channel cross-sectional area, mean depth, and width as functions of watershed drainage area.

  18. Serological diagnosis of North American Paragonimiasis by Western blot using Paragonimus kellicotti adult worm antigen.

    Science.gov (United States)

    Fischer, Peter U; Curtis, Kurt C; Folk, Scott M; Wilkins, Patricia P; Marcos, Luis A; Weil, Gary J

    2013-06-01

    Abstract. We studied the value of an IgG Western blot (WB) with Paragonimus kellicotti (Pk) antigen for diagnosis of North American paragonimiasis. The test was evaluated with sera from patients with Pk and Paragonimus westermani infections, with control sera from patients with other helminth infections, and sera from healthy Americans. All 11 proven Pk infection sera and two samples from suspected cases that were negative by P. westermani WB at the Centers for Disease Control and Prevention (CDC) contained antibodies to antigens at 34 kDa and at 21/23 kDa. Seven of 7 P. westermani sera contained antibodies to the 34 kDa antigen, but only 2 recognized the 21/23 kDa doublet. No control samples were reactive with these antigens. Antibody reactivity declined after praziquantel treatment. Thus, the P. kellicotti WB appears to be superior to P. westermani WB for diagnosing Pk infections, and it may be useful for assessing responses to treatment.

  19. Can the climate background of western North Pacific typhoon activity be predicted by climate model?

    Institute of Scientific and Technical Information of China (English)

    LANG XianMei; WANG HuiJun

    2008-01-01

    Based on the observation and reanalysis data through 1948-2004, the vertical shear of zonal wind, outgoing Iongwave radiation, and divergence fields in the lower and upper troposphere during summer are revealed to correlate significantly with the concurrent western North Pacific (WNP) typhoon frequency, and they therefore can be regarded as predictors for the WNP typhoon activity anomaly. After that, the 34-year (1970-2003) ensemble hindcast experiments are performed by the nine-level atmospheric general circulation model developed at the Institute of Atmospheric Physics Under the Chinese Academy of Sciences (IAP9L-AGCM), aiming to investigate the numerical predictability of the summer vertical shear of zonal wind and divergence field in the lower troposphere. It is found that the temporal correlation coefficients between the hindcast and observation are 0.70 and 0.62 for the vertical shear of zonal wind and divergence field, respectively. This suggests that the model possesses a large potential skill for predicting the large-scale climate background closely related to the WNP typhoon activity, and the model is therefore capable of performing the real-time numerical prediction of the WNP typhoon activity anomaly to some extent.

  20. Reliability of Dental Attrition as a Sole Parameter for Age Estimation among North Western Adult Indians

    Directory of Open Access Journals (Sweden)

    J. Arora

    2014-09-01

    Full Text Available Dental ageing is important in medico legal cases when teeth are the only material available to the investigating agencies for identification of the deceased. Attrition, which is the wear of occlusal surface of tooth (a physiological change; can be used as a determinant parameter for this purpose. The present study has been undertaken to examine the reliability of attrition as a sole parameter for age estimation among North Western adult Indians. 109 (43males, 66 females single rooted freshly extracted teeth ranging in age from 18-75years were studied. Teeth were fixed, cleaned and sectioned labiolingually upto thickness of 1mm. Sections were then mounted and attrition was graded from 0-3 according to Gustafson’s method. Scores were subjected to regression equation to estimate age of an individual. Results of the present study revealed that this parameter is reliable in individuals of ≤ 60 years with an error of ±10years. However, periodontal disease severely affected the accuracy of age estimation from this parameter as is evident from the results. Statistically no significant difference was noted in absolute mean error of age in different age groups. No significant difference was observed in absolute mean error of age in both the sexes.

  1. The epidemiology of tick-borne relapsing fever in Bijar County, North-Western Iran

    Institute of Scientific and Technical Information of China (English)

    Hamid Kassiri; Ali Kasiri; Kobra Dostifar; Masoud Lotfi

    2014-01-01

    To explain the demographic and epidemiological aspects of found cases of illness in theBijar County, north-westernIran, in the year of2007-2008. Methods:In this descriptive study population included all febrile cases referring to health services centers ofBijarCounty.A confirmed case was defined as an individual who had both febrile disease and detection ofBorrelia in a peripheral blood smear byWright-Giemsa using dark-field microscop.Each patient was asked to fulfill a questionnaire including clinical and epidemiological features and demographic information ofTBRF. Results:During the year of2007-2008,11 cases have been reported fromBijarCounty.There were5 cases(45.4%) of the patients younger than10 years,6 cases(54.5%) were10-19 years old. Of the patients,63.6% occurred in summer and27.3% in spring.All cases developed during the months ofMay toOctober.Fever and chills, the most common symptoms, occured in all patients. Most(54.5%) of the cases were students and the remaining were children.Approximately72.7% of the patients were keeping cattle and sheep near or inside their homes.

  2. Interannual Variation of Multiple Tropical Cyclone Events in the Western North Pacific

    Institute of Scientific and Technical Information of China (English)

    GAO Jianyun; Tim LI

    2012-01-01

    The interannual variability of occurrence of multiple tropical cyclone (MTC) events during June-October in the western North Pacific (WNP) was examined for the period 1979-2006.The number of the MTC events ranged from 2 to 9 per year,exhibiting a remarkable year-to-year variation.Seven active and seven inactive MTC years were identified.Compared to the inactive years,tropical cyclone genesis locations extended farther to the east and in the meridional direction during the active MTC years.A composite analysis shows that inactive MTC years were often associated with the El Ni(n)o decaying phase,as warm SST anomalies in the equatorial eastern-central Pacific in the preceding winter transitioned into cold sea surface temperature (SST) anomalies in the concurrent summer.Associated with the SST evolution were suppressed low-level cyclonic vorticity and weakened convection in the WNP monsoon region.In addition to the mean flow difference,significant differences between active and inactive MTC years were also found in the strength of the atmospheric intraseasonal oscillation (ISO).Compared with inactive MTC years,ISO activity was much stronger along the equator and in the WNP region during active MTC years.Both westward- and northward-propagating ISO spectrums strengthened during active MTC years compared to inactive years.The combined mean state and ISO activity changes may set up a favorable environment for the generation of MTC events.

  3. Nitrate Determination of Vegetables in Varzeghan City, North-western Iran

    Directory of Open Access Journals (Sweden)

    Parviz Nowrouz

    2012-12-01

    Full Text Available Background: Vegetables play an important role in human nutrition. Nitrate content is a signifi-cant quality criterion to determine characteristic of vegetables. About 80% of nitrate intake in human is from vegetables and fruits. High dietary intake of nitrate is seen as an undesirable be-cause of its association with gastric cancer and infantile methemoglobinemia. Varzeghan, North-western Iran is one of the cities with high Age-standardized incidence rates (ASR of gastric can-cer in Iran. Currently, in Varzeghan there is no available and accurate information describing ni-trate concentration as one of the important risk factors of vegetables for human consumption.Methods: In this cross sectional study totally 11 types of vegetables (cabbage, lettuce, spinach, parsley, coriander, dill, leek, fenugreek, tarragon, fumitory and mint from several different green-grocery of Varzeghan were collected in spring (April and autumn (November and December 2011 and their nitrate contents were analyzed.Results: Mean nitrate contents at the above noted fresh vegetables were 161, 781, 83, 707, 441,501, 1702, 684, 805, 772 and 191 mg NO3-kg-1 respectively. In none of the 11 fresh vegetablesnitrate content were not more than established limitations.Conclusion: Nitrate concentrations were below of others reported at different countries. The mean concentration of nitrate at all vegetables in autumn was higher than in spring significantly.

  4. Simulations of tropical cyclogenesis associated with different monsoon trough patterns over the western North Pacific

    Science.gov (United States)

    Cao, Xi; Chen, Guanghua; Li, Tim; Ren, Fumin

    2016-08-01

    The numerical simulations of tropical cyclone (TC) genesis during the strong and weak monsoon trough (MT) years, in which meteorological fields are composited, are conducted using advanced research weather research and forecasting model. The simulation results show that both tropical disturbances tend to form in the east of the western North Pacific (WNP) near 160°-170°E during the strong and weak MT years. During the strong MT years, there is a faster formation rate of TC. The eastward-extending MT gradually evolves into a closed monsoon gyre over the WNP during the early stage. The following rapid development of TC can be attributed to the enhanced lower-level southwesterly flows induced by the cross-equatorial currents, enhanced easterly winds, and weak vertical wind shear, which provide a favorable environment for TC genesis. The strengthened large-scale circulation spawns abundant convective updrafts resulting in the aggregation of cyclonic vorticity. In contrast, during the weak MT years, the westward-retreated MT gradually evolves into expansive easterly winds over the WNP. Two episodes of convective updrafts are triggered with a longer interval, and thus lead to a slower TC genesis compared with that during the strong MT years.

  5. Geodiversity action plans for the enhancement of geoheritage in the Piemonte region (north-western Italy

    Directory of Open Access Journals (Sweden)

    Elena Ferrero

    2012-07-01

    Full Text Available A geoethical approach to geodiversity allows better understanding of the value of abiotic nature and enhances its conservation and development. Our basic assumption is that even during an economical crisis, geoheritage sites can serve both public and private interests. A set of nine strategic geothematic areas were chosen to represent the geodiversity of the Piemonte region, north-western Italy, each of which is characterized by great potential for scientific studies, enhancement of public understanding of science, recreational activities, and economic support to the local communities. Specialized research teams individuated critical aspects to advance our knowledge of the geological history of the Piemonte region, through climate and environmental changes, natural hazards, soil processes, and georesources. The scientific concepts and techniques were coupled with geodiffusion actions and products: not only geosites, but also museum collections, evidence of mining and quarrying activities, science exhibitions, and nature trails. The preliminary results have allowed action plans to be developed with local partners, to assess the geoheritage management requirements. A series of investigations were carried out to improve the visual representation of the geological processes and the evolutionary scenarios. Further outcomes of the project will include didactic tools for educators, schools, and the public in general.

  6. Phylogeography of Camassia quamash in western North America: postglacial colonization and transport by indigenous peoples.

    Science.gov (United States)

    Tomimatsu, Hiroshi; Kephart, Susan R; Vellend, Mark

    2009-09-01

    Recent human activities have spread numerous plant species across the globe, yet it is unclear to what degree historical human activities influenced plant dispersal. In western North America, Camassia quamash was one of the most important food plants for indigenous peoples, who transported its propagules either intentionally or accidentally. We investigated how human and natural dispersal might have contributed to the current pattern of spatial genetic structure in C. quamash by performing phylogeographical surveys at two geographical scales. We sequenced two noncoding regions of chloroplast deoxyribonucleic acid (DNA) in 226 individuals from 53 populations of C. quamash as well as 126 individuals from 21 populations of the non-food plant Zigadenus venenosus. Contrary to the expectation of anthropogenic transport, C. quamash populations did not exhibit weaker genetic structure than Z. venenosus populations. We also failed to find convincing evidence for signatures of transport. Instead, our data showed strong effects of past glaciation and geographical barriers of the mountains in the Cascade Range, Olympic Peninsula and Vancouver Island. West of the Cascades, the species appears to have largely migrated northward from a southern refugium after deglaciation, whereas few populations having a highly divergent haplotype might have survived in southwestern Washington. Our data suggest that despite substantial ethnobotanical evidence for anthropogenic transport, the current pattern of genetic structure of C. quamash does not show any detectable signatures of transport by indigenous peoples and is better understood as the result of natural dispersal processes.

  7. Enhanced Particulate Organic Carbon Export at Eddy Edges in the Oligotrophic Western North Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Yung-Yen Shih

    Full Text Available Mesoscale eddies in the subtropical oligotrophic ocean are ubiquitous and play an important role in nutrient supply and oceanic primary production. However, it is still unclear whether these mesoscale eddies can efficiently transfer CO2 from the atmosphere to deep waters via biological pump because of the sampling difficulty due to their transient nature. In 2007, particulate organic carbon (POC fluxes, measured below the euphotic zone at the edge of warm eddy were 136-194 mg-C m-2 d-1 which was greatly elevated over that (POC flux = 26-35 mg-C m-2 d-1 determined in the nutrient-depleted oligotrophic waters in the Western North Pacific (WNP. In 2010, higher POC fluxes (83-115 mg-C m-2 d-1 were also observed at the boundary of mesoscale eddies in the WNP. The enhanced POC flux at the edge of eddies was mainly attributed to both large denuded diatom frustules and zooplankton fecal pellets based on scanning electron microscopy (SEM examination. The result suggests that mesoscale eddies in the oligotrophic waters in the subtropical WNP can efficiently increase the oceanic carbon export flux and the eddy edge is a crucial conduit in carbon sequestration to deep waters.

  8. Event-based surveillance in north-western Ethiopia: experience and lessons learnt in the field

    Directory of Open Access Journals (Sweden)

    Yumi Toyama

    2015-08-01

    Full Text Available This study piloted an event-based surveillance system at the health centre (HC level in Ethiopia. The system collects rumours in the community and registers them in rumour logbooks to record events of disease outbreaks and public health emergencies. Descriptive analysis was conducted on the events captured at the 59 study HCs in the Amhara Region in north-western Ethiopia between October 2013 and November 2014. A total of 126 rumours were registered at two thirds of the HCs during the study period. The average event reporting time was 3.8 days; response time of the HCs was 0.6 days, resulting in a total response time of 4.4 days. The most commonly reported rumours were measles-related (n = 90, 71%. These rumours followed a similar pattern of measles cases reported in the routine surveillance system. The largest proportion of rumours were reported by community members (n = 38, 36% followed by health post workers (n = 36, 29% who were normally informed by the community members about the rumours. This surveillance system was established along with an existing indicator-based surveillance system and was simple to implement. The implementation cost was minimal, requiring only printing and distribution of rumour logbooks to the HCs and brief orientations to focal persons. In countries where routine surveillance is still weak, an event-based surveillance system similar to this should be considered as a supplementary tool for disease monitoring.

  9. Hierarchical modeling of bycatch rates of sea turtles in the western North Atlantic

    Science.gov (United States)

    Gardner, B.; Sullivan, P.J.; Epperly, S.; Morreale, S.J.

    2008-01-01

    Previous studies indicate that the locations of the endangered loggerhead Caretta caretta and critically endangered leatherback Dermochelys coriacea sea turtles are influenced by water temperatures, and that incidental catch rates in the pelagic longline fishery vary by region. We present a Bayesian hierarchical model to examine the effects of environmental variables, including water temperature, on the number of sea turtles captured in the US pelagic longline fishery in the western North Atlantic. The modeling structure is highly flexible, utilizes a Bayesian model selection technique, and is fully implemented in the software program WinBUGS. The number of sea turtles captured is modeled as a zero-inflated Poisson distribution and the model incorporates fixed effects to examine region-specific differences in the parameter estimates. Results indicate that water temperature, region, bottom depth, and target species are all significant predictors of the number of loggerhead sea turtles captured. For leatherback sea turtles, the model with only target species had the most posterior model weight, though a re-parameterization of the model indicates that temperature influences the zero-inflation parameter. The relationship between the number of sea turtles captured and the variables of interest all varied by region. This suggests that management decisions aimed at reducing sea turtle bycatch may be more effective if they are spatially explicit. ?? Inter-Research 2008.

  10. Recent growth of conifer species of western North America: Assessing spatial patterns of radial growth trends

    Science.gov (United States)

    McKenzie, D.; Hessl, Amy E.; Peterson, D.L.

    2001-01-01

    We explored spatial patterns of low-frequency variability in radial tree growth among western North American conifer species and identified predictors of the variability in these patterns. Using 185 sites from the International Tree-Ring Data Bank, each of which contained 10a??60 raw ring-width series, we rebuilt two chronologies for each site, using two conservative methods designed to retain any low-frequency variability associated with recent environmental change. We used factor analysis to identify regional low-frequency patterns in site chronologies and estimated the slope of the growth trend since 1850 at each site from a combination of linear regression and time-series techniques. This slope was the response variable in a regression-tree model to predict the effects of environmental gradients and species-level differences on growth trends. Growth patterns at 27 sites from the American Southwest were consistent with quasi-periodic patterns of drought. Either 12 or 32 of the 185 sites demonstrated patterns of increasing growth between 1850 and 1980 A.D., depending on the standardization technique used. Pronounced growth increases were associated with high-elevation sites (above 3000 m) and high-latitude sites in maritime climates. Future research focused on these high-elevation and high-latitude sites should address the precise mechanisms responsible for increased 20th century growth.

  11. Plasmodium vivax and Mansonella ozzardi co-infection in north-western Argentina.

    Science.gov (United States)

    Dantur Juri, María J; Veggiani Aybar, Cecilia A; Ortega, Eugenia S; Galante, Guillermina B; Zaidenberg, Mario O

    2013-01-01

    A case of co-infection with Plasmodium vivax and Mansonella ozzardi was detected in a blood sample from a person who had shown symptoms of malaria and lived in a city that was close to the Argentina/Bolivia border. The case was detected during a random revision of thick and thin smears from patients diagnosed with malaria from various towns and cities located in north-western Argentina between 1983 and 2001. Trophozoites of P. vivax were observed in the thin blood smear along with M. ozzardi microfilaria (larval form), which presented a long, slender, pointed anucleate tail and the absence of the sheath. This last characteristic is shared with Mansonella perstans, Mansonella streptocerca and Onchocerca volvulus. More rigorously controlled studies to detect other co-infection cases in the area as well as the possibility of importation from Bolivia into Argentina are currently ongoing. The relationship between the malaria parasite and microfilaria, the potential effect of malaria treatment on the development of M. ozzardi, and the possible impact of this microfilaria on the immunity of a person against P. vivax are all still unknown. This contribution constitutes a point of focus for future studies involving the interaction between the parasites and the potential risk that humans are exposed to. PMID:23866313

  12. Study on Clinical Bovine Dermatophilosis and its Potential Risk Factors in North Western Ethiopia

    Directory of Open Access Journals (Sweden)

    Meseret Admassu and Sefinew Alemu

    2011-02-01

    Full Text Available A cross-sectional study of dermatophilosis was undertaken from October 2008 to March 2009 on 3456 cattle (3181 indigenous zebu and 275 Holestien-zebu cross with the aim of determining prevalence and associated risk factors in urban and periurban areas of Bahir Dar, north western Ethiopia. Culturing of Dermatiphilus congolensis and Giemsa staining were the techniques used. Thirty six of 3456 examined animals (1.04% had clinical dermatophilosis. Prevalence was higher in cross bred (5.5% than in indigenous zebu (0.7% cattle, in male cattle (1.7% than in female (0.8% , in adults (1.2% than in young (0.8% age groups, in wet (1.6% than in dry season (0.5%, and in cattle infested with tick (2.7% than cattle with no tick infestation (0.4%. Statistically significant difference (p# 0.05 was observed in the prevalence between breeds of cattle, between age groups, between wet and dry seasons, and between cattle with and without tick infestation. Amblyoma variegatum was identified. The study indicated dermatophilosis is a potential determinant factor for the dairy development strategy started through cross breeding in the study area. Tick control especially on crossbred cattle is suggested to reduce the risk of dermatophilosis.

  13. Survey of thermophilic Campylobacter species in cats and dogs in north-western Nigeria

    Directory of Open Access Journals (Sweden)

    Adewale Kolawale

    2010-12-01

    Full Text Available This study was conducted in north-western Nigeria to investigate the role of cats and dogs as potential reservoirs of thermophilic Campylobacter species. Faecal samples were analysed from 104 cats and 141 dogs between March 2007 and March 2009. The samples were collected from animals in households, those presented to veterinary premises and feline colonies. Campylobacter spp. were isolated from 39 (27.7% and 19 (18.3% dogs and cats, respectively. There was no significant difference in isolation rate observed between dogs (27.7% and cats (18.3% and there was also no significance difference between younger and older dogs; 23.1% (young compared to 30.3% (older dogs, but a significant difference was seen between young (4.3% and older (29.3% cats. Campylobacter upsaliensis predominated in the isolates, accounting for 89.5% and 74.4% of the positive samples in cats and dogs, respectively, C. jejuni constituted 21.1% and 23.1% of the positive samples from cats and dogs, respectively. This finding is an indication that dogs and cats frequently shed thermophilic Campylobacter spp. which could be of public health importance. To establish the zoonotic significance of canine and feline Campylobacter, isolates need to be further characterised and compared. This is the first study on the prevalence of campylobacter in cats and dogs in the region.

  14. Bioprospecting of plant growth promoting psychrotrophic Bacilli from the cold desert of north western Indian Himalayas.

    Science.gov (United States)

    Yadav, Ajar Nath; Sachan, Shashwati Ghosh; Verma, Priyanka; Saxena, Anil Kumar

    2016-02-01

    The plant growth promoting psychrotrophic Bacilli were investigated from different sites in north western Indian Himalayas. A total of 247 morphotypes were obtained from different soil and water samples and were grouped into 43 clusters based on 16S rDNA-RFLP analysis with three restriction endonucleases. Sequencing of representative isolates has revealed that these 43 Bacilli belonged to different species of 11 genera viz., Desemzia, Exiguobacterium, Jeotgalicoccus, Lysinibacillus, Paenibacillus, Planococcus, Pontibacillus, Sinobaca, Sporosarcina, Staphylococcus and Virgibacillus. With an aim to develop microbial inoculants that can perform efficiently at low temperatures, all representative isolates were screened for different plant growth promoting traits at low temperatures (5-15 degrees C). Among the strains, variations were observed for production (%) of indole-3-acetic acid (20), ammonia (19), siderophores (11), gibberellic acid (4) and hydrogen cyanide (2); solubilisation (%) of zinc (14), phosphate (13) and potassium (7); 1-aminocyclopropane-1-carboxylate deaminase activity (6%) and biocontrol activity (4%) against Rhizoctonia solani and Macrophomina phaseolina. Among all the strains, Bacillus licheniformis, Bacillus muralis, Desemzia incerta, Paenibacillus tylopili and Sporosarcina globispora were found to be potent candidates to be developed as inoculants as they exhibited multiple PGP traits at low temperature. PMID:26934782

  15. Sub-Seafloor Carbon Dioxide Storage Potential on the Juan de Fuca Plate, Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Jerry Fairley; Robert Podgorney

    2012-11-01

    The Juan de Fuca plate, off the western coast of North America, has been suggested as a site for geological sequestration of waste carbon dioxide because of its many attractive characteristics (high permeability, large storage capacity, reactive rock types). Here we model CO2 injection into fractured basalts comprising the upper several hundred meters of the sub-seafloor basalt reservoir, overlain with low-permeability sediments and a large saline water column, to examine the feasibility of this reservoir for CO2 storage. Our simulations indicate that the sub-seafloor basalts of the Juan de Fuca plate may be an excellent CO2 storage candidate, as multiple trapping mechanisms (hydrodynamic, density inversions, and mineralization) act to keep the CO2 isolated from terrestrial environments. Questions remain about the lateral extent and connectivity of the high permeability basalts; however, the lack of wells or boreholes and thick sediment cover maximize storage potential while minimizing potential leakage pathways. Although promising, more study is needed to determine the economic viability of this option.

  16. Fasciola hepatica in goats from north-western Spain: Risk factor analysis using a capture ELISA.

    Science.gov (United States)

    Pérez-Creo, Ana; Díaz, Pablo; López, Ceferino; Béjar, Juan Pablo; Martínez-Sernández, Victoria; Panadero, Rosario; Díez-Baños, Pablo; Ubeira, Florencio M; Morrondo, Patrocinio

    2016-02-01

    In order to study the seroprevalence of Fasciola hepatica infection in goats from north-western Spain, a total of 603 serum samples from 47 herds were tested using a capture ELISA (MM3-SERO). The identification of risk factors was assessed by a mixed-effects logistic regression analysis. The results showed that F. hepatica is widespread in this area with 57.4% of the herds and 22.7% of the animals testing positive. Breed and age were identified as determining factors for caprine F. hepatica infection. Seroprevalence in cross-bred animals was significantly higher than in the autochthonous Cabra Galega breed. A significantly higher seroprevalence was observed in older animals. The use of locally adapted breeds and the implementation of suitable management practices could provide a substantial improvement over the current F. hepatica control measures carried out in goat herds and should be considered when designing new F. hepatica control programs.

  17. Nutrients, suspended sediment, and pesticides in streams in the Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1993-95

    Science.gov (United States)

    Tornes, L.H.; Brigham, M.E.; Lorenz, D.L.

    1997-01-01

    Fifteen stream sites in the Red River of the North Basin were sampled during 1993-95 to assess levels of nutrients, organic carbon, and suspended sediment, and five sites were sampled for pesticides. Concentrations varied seasonally and were related to periods of fertilizer and pesticide application, and to runoff. Concentrations of several constituents were related to the physiographic area the stream drains, but other factors such as local land use frequently complicated that relation.

  18. New Data on Land Subsidence Phenomena Due to Excessive Ground Water Withdrawal in the Western Thessaly Basin, Central Greece

    Science.gov (United States)

    Sideri, D.; Rozos, D.; Loupasakis, C.; Kotsanis, D.

    2012-04-01

    The Western Thessaly basin is a major plain which is located in Central Greece. During the last decades this area exhibits an intensive development, mainly based on the agricultural economy. Due to that agricultural development, several thousand boreholes have been drilled for irrigation purposes. The overexploitation of the ground water, in the wider area, has triggered the manifestation of land subsidence phenomena. These phenomena were firstly observed in 2002 in the Stavros and Farsala sites (southeast part of the Western Thessaly basin), in the form of various surface ruptures. In 2009 similar phenomena appeared in Agios Georgios village and in 2011 in Anohori and Katohori villages, which are located between Farsala and Stavros towns. The geological environment of the research area consists of terrestrial sands and gravels horizons Pleistocene in age, with brown and grey clayey silt to silty clay intercalations. These alternations of permeable coarse-grained deposits (aquifers) with impermeable to low permeability strata (aquitards) create a number of successive semi-confined to confined aquifers, sometimes artesians. Land subsidence deformations were noticed both along the margins as well as in the inner part of the basin. Surface ruptures are observed along the margins of the basin where the bedrock outcrops and generally in areas where the thickness of the Pleistocene deposits appear to be small. On the contrary, in the parts of the basin with thick deposits, the subsidence of the Pleistocene formations can be noticed by the extraction of the water wells pipes. During this research a detailed geotechnical and hydrogeological survey was carried out covering the study area. Several hundreds of boreholes, drilled in the frame of previous geological-geotechnical investigations, were analyzed and interpreted, along with previous data, referring to the stratigraphy of the study area. As a result, the highly compressible units, which may be responsible for

  19. Loess in the foothills of the western Carpathians and its importance for paleoenvironmental reconstruction towards the Carpathian Basin

    Science.gov (United States)

    Obreht, Igor; Lehmkuhl, Frank; Kels, Holger; Hambach, Ulrich; Schulte, Philipp; Eckmeier, Eileen; Klasen, Nicole; Bösken, Janina; Krauss, Lydia; Zeeden, Christian

    2016-04-01

    The CRC 806 "Our way to Europe" focuses on the first arrival and dispersal of anatomically modern humans (AMH) from Africa to Europe. Within the second phase of this project, a subproject investigates the eastern trajectory of AMH dispersal through the Levant and Balkan Peninsula. Special attention is given to the Carpathian Basin and the surrounding foothills of the Carpathian Mountains. To this date, most Paleolithic sites in this region have been found in the foothills. To test the hypothesis whether this observation presents a valid pattern, or if it may be biased by the fact that the lowlands of the Carpathian Basin are covered by thick loess deposits overlying the archaeologic remains of AMH, beside improved archeological perspective it is also necessarily to understand the regional past climatic conditions from the time of the first AMH appearance in Europe around 40 ka ago. Loess-paleosol sequences (LPS) from the lowlands of the Carpathian Basin preserve almost continuous records of past environmental changes from this region. During the last decade, LPS were intensively investigated resulting in a good overall understanding of general paleoenvironmental conditions in the Carpathian Basin itself. However, short LPS from the surrounding mountains have only been studied in few localities and not well understood yet. This presents a challenge in understanding the past environmental conditions of the foothill areas which are hypothesized to be a preferred habitat of the AMH. As an attempt to bridge this gap, we are presenting the initial results from the Şanoviţa section (western Romania), located at the transition from lowlands to foothills of the Carpathians. Based on a multi-proxy study (grain-size, rock magnetism, color and geochemical analysis) of last glacial sediments, we improve the understanding of paleoenvironmental conditions between the Carpathian Basin and the western flank of the Carpathian Mountains. Şanoviţa is located at the upper end of a

  20. Aerosol properties over the western Mediterranean Basin: temporal and spatial variability

    Science.gov (United States)

    Lyamani, H.; Valenzuela, A.; Perez-Ramirez, D.; Toledano, C.; Granados-Muñoz, M. J.; Olmo, F. J.; Alados-Arboledas, L.

    2014-08-01

    This study focuses on the analysis of AERONET aerosol data obtained over Alborán Island (35.95° N, 3.01° W, 15 m a.s.l.) in the western Mediterranean from July 2011 to January 2012. Additional aerosol data from three nearest AERONET stations and the Maritime Aerosol Network (MAN) were also analyzed in order to investigate the aerosol temporal and spatial variations over this scarcely explored region. Aerosol load over Alborán was significantly larger than that reported for open oceanic areas not affected by long-range transport. High aerosol loads over Alborán were mainly associated with desert dust transport from North Africa and occasional advection of anthropogenic fine particles from Italy. The fine particle load observed over Alborán was surprisingly similar to that obtained over the other three nearest AERONET stations in spite of the large differences in local aerosol sources. The results from MAN acquired over the Mediterranean Sea, Black Sea and Atlantic Ocean from July to November 2011 revealed a pronounced predominance of fine particles during the cruise period. Alborán was significantly less influenced by anthropogenic particles than the Black Sea and central and eastern Mediterranean regions during the cruise period. Finally, the longer AERONET dataset from Málaga (36.71° N, 4.4° W, 40 m a.s.l.), port city in southern Spain, shows that no significant changes in columnar aerosol loads since the European Directive on ship emissions was implemented in 2010 were observed over this site.

  1. Arctic and boreal ecosystems of western North America as components of the climate system

    Science.gov (United States)

    Chapin, F. S., III; McGuire, A.D.; Randerson, J.; Pielke, R., Sr.; Baldocchi, D.; Hobbie, S.E.; Roulet, Nigel; Eugster, W.; Kasischke, E.; Rastetter, E.B.; Zimov, S.A.; Running, S.W.

    2000-01-01

    Synthesis of results from several Arctic and boreal research programmes provides evidence for the strong role of high-latitude ecosystems in the climate system. Average surface air temperature has increased 0.3??C per decade during the twentieth century in the western North American Arctic and boreal forest zones. Precipitation has also increased, but changes in soil moisture are uncertain. Disturbance rates have increased in the boreal forest; for example, there has been a doubling of the area burned in North America in the past 20 years. The disturbance regime in tundra may not have changed. Tundra has a 3-6-fold higher winter albedo than boreal forest, but summer albedo and energy partitioning differ more strongly among ecosystems within either tundra or boreal forest than between these two biomes. This indicates a need to improve our understanding of vegetation dynamics within, as well as between, biomes. If regional surface warming were to continue, changes in albedo and energy absorption would likely act as a positive feedback to regional warming due to earlier melting of snow and, over the long term, the northward movement of treeline. Surface drying and a change in dominance from mosses to vascular plants would also enhance sensible heat flux and regional warming in tundra. In the boreal forest of western North America, deciduous forests have twice the albedo of conifer forests in both winter and summer, 50-80% higher evapotranspiration, and therefore only 30-50% of the sensible heat flux of conifers in summer. Therefore, a warming-induced increase in fire frequency that increased the proportion of deciduous forests in the landscape, would act as a negative feedback to regional warming. Changes in thermokarst and the aerial extent of wetlands, lakes, and ponds would alter high-latitude methane flux. There is currently a wide discrepancy among estimates of the size and direction of CO2 flux between high-latitude ecosystems and the atmosphere. These

  2. Crustal structure at the western end of the North Anatolian Fault Zone from deep seismic sounding

    Directory of Open Access Journals (Sweden)

    B. Baier

    2001-06-01

    Full Text Available The first deep seismic sounding experiment in Northwestern Anatolia was carried out in October 1991 as part of the "German - Turkish Project on Earthquake Prediction Research" in the Mudurnu area of the North Anatolian Fault Zone. The experiment was a joint enterprise by the Institute of Meteorology and Geophysics of Frankfurt University, the Earthquake Research Institute (ERI in Ankara, and the Turkish Oil Company (TPAO. Two orthogonal profiles, each 120 km in length with a crossing point near Akyazi, were covered in succession by 30 short period tape recording seismograph stations with 2 km station spacing. 12 shots, with charge sizes between 100 and 250 kg, were fired and 342 seismograms out of 360 were used for evaluation. By coincidence an M b = 4.5 earthquake located below Imroz Island was also recorded and provided additional information on Moho and the sub-Moho velocity. A ray tracing method orginally developed by Weber (1986 was used for travel time inversion. From a compilation of all data two generalized crustal models were derived, one with velocity gradients within the layers and one with constant layer velocities. The latter consists of a sediment cover of about 2 km with V p » 3.6 km/s, an upper crystalline crust down to 13 km with V p » 5.9 km/s, a middle crust down to 25 km depth with V p » 6.5 km/s, a lower crust down to 39 km Moho depth with V p » 7.0 km/s and V p » 8.05 km/s below the Moho. The structure of the individual profiles differs slightly. The thickest sediment cover is reached in the Izmit-Sapanca-trough and in the Akyazi basin. Of particular interest is a step of about 4 km in the lower crust near Lake Sapanca and probably an even larger one in the Moho (derived from the Imroz earthquake data. After the catastrophic earthquake of Izmit on 17 August 1999 this significant heterogeneity in crustal structure appears in a new light with regard to the possible cause of the Izmit earthquake. Heterogeneities in

  3. U-Pb Zircon Dating of the Yeniutan Granitic Intrusion in the Western Sector of the North Qilian Mountains

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Zircons from granodiorite and biotite granite in the Yeniutan granitic intrusion in the western North Qilian Mountains ylelded a weighted mean 206PH/apparent age of 460±3Ma, suggesting that the intrusion originated during the late stage of plate subuotion Its related Ta’ergou and Xiaoliugou deposits are two of the few large tungsten deposits formed in the plate subduction environment in the world. The U-Pb dating of the zircons from the biotite granite gave a discordant lower intercept age of 183±4 Ma, which implies that the Yanshanian event was probably superimposed on the North Qilian region.

  4. High-resolution seismic analysis of the coastal Mecklenburg Bay (North German Basin): the pre-Alpine evolution

    Science.gov (United States)

    Zöllner, H.; Reicherter, K.; Schikowsky, P.

    2008-09-01

    The pre-Alpine structural and geological evolution in the northern part of the North German Basin have been revealed on the basis of a very dense reflection seismic profile grid. The study area is situated in the coastal Mecklenburg Bay (Germany), part of the southwestern Baltic Sea. From the central part of the North German Basin to the northern basin margin in the Grimmen High area a series of high-resolution maps show the evolution from the base Zechstein to the Lower Jurassic. We present a map of basement faults affecting the pre-Zechstein. The pre-Alpine structural evolution of the region has been determined from digital mapping of post-Permian key horizons traced on the processed seismic time sections. The geological evolution of the North German Basin can be separated into four distinct periods in the Rerik study area. During Late Permian and Early Triassic evaporites and clastics were deposited. Salt movement was initiated after the deposition of the Middle Triassic Muschelkalk. Salt pillows, which were previously unmapped in the study area, are responsible for the creation of smaller subsidence centers and angular unconformities in the Late Triassic Keuper, especially in the vicinity of the fault-bounded Grimmen High. In this area, partly Lower Jurassic sediments overlie the Keuper unconformably. The change from extension to compression in the regional stress field remobilized the salt, leading to a major unconformity marked at the base of the Late Cretaceous.

  5. Late Pliocene and Early Pleistocene Temperature Reconstructions from Paleolakes of the West Turkana and North Awash Basins, East Africa

    Science.gov (United States)

    Castañeda, I. S.; Thompson-Munson, M.; Lupien, R.; Russell, J. M.

    2015-12-01

    The Hominin Sites and Paleolakes Drilling Project (HSPDP) aims to reconstruct past environments of the East African Rift Valley from locations in close proximity to some of the world's most important fossil hominin and artifact sites. In this study, we investigate sediments from the West Turkana and North Awash Basins, which were recently drilled as part of the HSPDP. The North Awash Basin contains abundant early hominin fossils and the lakebeds of the Hadar Formation (~3.6 to ~2.9 Ma) will provide a record of climate variability during the Pliocene, prior to the intensification of Northern Hemisphere glaciation at ~2.7 Ma. The lakebeds of the Turkana Basin are Early Pleistocene in age (~1.9 to ~1.45 Ma) and span the interval that includes some the earliest fossils of Homo rudolfensis and H. ergaster/erectus. Here we examine the organic geochemistry of West Turkana and North Awash Basin sediments and investigate the use of proxies based on isoprenoid and branched glycerol dialkyl glycerol tetraethers (GDGTs) to reconstruct temperature, including TEX86 and the methylation and cyclization (MBT and CBT) ratios and relative abundances of branched GDGTs. We also examine variability in the abundances and ratios of plant leaf waxes (n-alkanes) to provide insight into past vegetation changes on the East African landscape.

  6. Status and understanding of groundwater quality in the North San Francisco Bay groundwater basins, 2004

    Science.gov (United States)

    Kulongoski, Justin T.; Belitz, Kenneth; Landon, Matthew K.; Farrar, Christopher

    2010-01-01

    Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) North San Francisco Bay study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in northern California in Marin, Napa, and Sonoma Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA North San Francisco Bay study was designed to provide a spatially unbiased assessment of untreated groundwater quality in the primary aquifer systems. The assessment is based on water-quality and ancillary data collected by the USGS from 89 wells in 2004 and water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer systems (hereinafter referred to as primary aquifers) were defined by the depth interval of the wells listed in the CDPH database for the North San Francisco Bay study unit. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOC), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifers of the North San Francisco Bay study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or

  7. Gas desorption and adsorption isotherm studies of coals in the Powder River basin, Wyoming and adjacent basins in Wyoming and North Dakota

    Science.gov (United States)

    Stricker, Gary D.; Flores, Romeo M.; McGarry, Dwain E.; Stillwell, Dean P.; Hoppe, Daniel J.; Stillwell, Cathy R.; Ochs, Alan M.; Ellis, Margaret S.; Osvald, Karl S.; Taylor, Sharon L.; Thorvaldson, Marjorie C.; Trippi, Michael H.; Grose, Sherry D.; Crockett, Fred J.; Shariff, Asghar J.

    2006-01-01

    The U.S. Geological Survey (USGS), in cooperation with the State Office, Reservoir Management Group (RMG), of the Bureau of Land Management (BLM) in Casper (Wyoming), investigated the coalbed methane resources (CBM) in the Powder River Basin, Wyoming and Montana, from 1999 to the present. Beginning in late 1999, the study also included the Williston Basin in Montana and North and South Dakota and Green River Basin and Big Horn Basin in Wyoming. The rapid development of CBM (referred to as coalbed natural gas by the BLM) during the early 1990s, and the lack of sufficient data for the BLM to fully assess and manage the resource in the Powder River Basin, in particular, gave impetus to the cooperative program. An integral part of the joint USGS-BLM project was the participation of 25 gas operators that entered individually into confidential agreements with the USGS, and whose cooperation was essential to the study. The arrangements were for the gas operators to drill and core coal-bed reservoirs at their cost, and for the USGS and BLM personnel to then desorb, analyze, and interpret the coal data with joint funding by the two agencies. Upon completion of analyses by the USGS, the data were to be shared with both the BLM and the gas operator that supplied the core, and then to be released or published 1 yr after the report was submitted to the operator.

  8. Watershed boundaries and geographic isolation: patterns of diversification in cutthroat trout from western North America

    Directory of Open Access Journals (Sweden)

    Loxterman Janet L

    2012-03-01

    Full Text Available Abstract Background For wide-ranging species, intraspecific variation can occur as a result of reproductive isolation from local adaptive differences or from physical barriers to movement. Cutthroat trout (Oncorhynchus clarkii, a widely distributed fish species from North America, has been divided into numerous putative subspecies largely based on its isolation in different watersheds. In this study, we examined mtDNA sequence variation of cutthroat trout to determine the major phylogenetic lineages of this polytypic species. We use these data as a means of testing whether geographic isolation by watershed boundaries can be a primary factor organizing intraspecific diversification. Results We collected cutthroat trout from locations spanning almost the entire geographic range of this species and included samples from all major subspecies of cutthroat trout. Based on our analyses, we reveal eight major lineages of cutthroat trout, six of which correspond to subspecific taxonomy commonly used to describe intraspecific variation in this species. The Bonneville cutthroat trout (O. c. utah and Yellowstone cutthroat trout (O. c. bouvieri did not form separate monophyletic lineages, but instead formed an intermixed clade. We also document the geographic distribution of a Great Basin lineage of cutthroat trout; a group typically defined as Bonneville cutthroat trout, but it appears more closely related to the Colorado River lineage of cutthroat trout. Conclusion Our study indicates that watershed boundaries can be an organizing factor isolating genetic diversity in fishes; however, historical connections between watersheds can also influence the template of isolation. Widely distributed species, like cutthroat trout, offer an opportunity to assess where historic watershed connections may have existed, and help explain the current distribution of biological diversity across a landscape.

  9. Chemical evolution in the high arsenic groundwater of the Huhhot basin (Inner Mongolia, PR China) and its difference from the western Bengal basin (India)

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Abhijit, E-mail: amukh2@gmail.com [Bureau of Economic Geology, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78758 (United States); Bhattacharya, Prosun; Shi, Fei [KTH-International Groundwater Arsenic Research Group, Dept. of Land and Water Resources, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Fryar, Alan E. [Department of Earth and Environmental Sciences, University of Kentucky, Lexington, KY 40506 (United States); Mukherjee, Arun B. [Environmental Sciences, Dept. of Biological and Environmental Sciences, Helsinki University, P.O. Box 27, FIN-00014 Helsinki (Finland); Xie, Zheng M. [Department of Resources/Soil Sciences, Zhejiang University, Hangzhou 310029 (China); Jacks, Gunnar [KTH-International Groundwater Arsenic Research Group, Dept. of Land and Water Resources, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Bundschuh, Jochen [Instituto Costarricense de Electricidad, Apartado Postal 10032, 1000 San Jose (Costa Rica)

    2009-10-15

    Elevated As concentrations in groundwater of the Huhhot basin (HB), Inner Mongolia, China, and the western Bengal basin (WBB), India, have been known for decades. However, few studies have been performed to comprehend the processes controlling overall groundwater chemistry in the HB. In this study, the controls on solute chemistry in the HB have been interpreted and compared with the well-studied WBB, which has a very different climate, physiography, lithology, and aquifer characteristics than the HB. In general, there are marked differences in solute chemistry between HB and WBB groundwaters. Stable isotopic signatures indicate meteoric recharge in the HB in a colder climate, distant from the source of moisture, in comparison to the warm, humid WBB. The major-ion composition of the moderately reducing HB groundwater is dominated by a mixed-ion (Ca-Na-HCO{sub 3}-Cl) hydrochemical facies with an evolutionary trend along the regional hydraulic gradient. Molar ratios and thermodynamic calculations show that HB groundwater has not been affected by cation exchange, but is dominated by weathering of feldspars (allitization) and equilibrium with gibbsite and anorthite. Mineral weathering and mobilization of As could occur as recharging water flows through fractured, argillaceous, metamorphic or volcanic rocks in the adjoining mountain-front areas, and deposits solutes near the center of the basin. In contrast, WBB groundwater is Ca-HCO{sub 3}-dominated, indicative of calcite weathering, with some cation exchange and silicate weathering (monosiallitization).

  10. Petroleum resources assessment on the western part of the Kunsan Basin

    Energy Technology Data Exchange (ETDEWEB)

    Park, K.S.; Park, K.P.; Sunwoo, D.; Yoo, D.G.; Cheong, T.J.; Oh, J.H.; Bong, P.Y.; Son, J.D.; Lee, H.Y.; Ryu, B.J.; Son, B.K.; Hwang, I.G.; Kwon, Y.I.; Lee, Y.J.; Kim, H.J. [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1997-12-01

    Palynomorphs including spores, pollen and organic-walled microfossils and calcareous microfossils such as ostracods, charophytes and gastropods were studied for the biostratigraphic work of Kachi-1 and IIH-1Xa wells. All the microfossils yielded from two wells indicate nonmarine environment ranging from shallow lacustrine to fluvial one. The paleoclimates have been fluctuated between subtropical and cool temperate with arid/humid alternating conditions. The fluvial sandstone of the interval between 2017 m and 2021 m could be a potential reservoir rock in the well Kachi-1. The sandstone from 1587 m to 1592 could be also a potential reservoir rock even if further study is necessary for the cap rock. Content of organic matter is very low and the type is compared to III in the section penetrated by the above two wells. Thermal maturity might reach top of oil window at depth about 1200 m by Tmax and about 1300 m by biomarker analysis in the Kachi-1 well. On the basis of illite crystallinity, the top of oil generation zone could be located at the depth 1600 m. The thermal maturity could not be determined in the IIH-1Xa well, because of the extremely low organic matter content or bad state of samples. Hydrocarbon genetic potential is almost null in the both well except for a few sample in the thermally immature interval. Analysis of approximately 3,300 Line-km of multichannel seismic data integrated with 3 well data provides an insight of structural evolution of the western part of the Yellow Sea Basin. Tectonics of the rifting phase have been established on the basis of structural and stratigraphic analyses of depositional sequences and their seismic expressions. Based on available well data, the rifting probably began in the Cretaceous time had continued until Paleocene. It is considered that compressional force immediately after rifting event deformed sedimentary sections. During the period of Paleocene to middle Miocene, the sediments were deposited in stable

  11. Impact of stormwater infiltration basins on groundwater quality, Perth metropolitan region, Western Australia

    Science.gov (United States)

    Appleyard, S. J.

    1993-08-01

    Twelve bores were sunk adjacent to three stormwater infiltration basins in the Perth metropolitan area to examine the impact of runoff from a light industrial area, a medium-density residential area, and a major arterial road on groundwater quality, and to examine the hydrological response of the aquifer to runoff recharge. Automatic and manual water level monitoring between April and November 1990 indicated that groundwater levels responded within minutes to recharge from the infiltration basins. Peak water levels of up to 2.5 m above rest levels occurred 6 24 h after the commencement of ponding in the infiltration basins. There was a marked reduction in salinity and increase in dissolved oxygen concentrations in the upper part of the aquifer downgradient of the infiltration basins. Concentrations of toxic metals, nutrients, pesticides, and phenolic compounds in groundwater near the infiltration basins were low and generally well within Australian drinking water guidelines. However, sediment in the base of an infiltration basin draining a major road contained in excess of 3500 ppm of lead. Phthalates, which are US EPA priority pollutants, were detected in all but one bore near the infiltration basins. Their detection may be a sampling artifact, but they may also be derived from the plastic litter that accumulates in the infiltration basins. The concentration of iron in groundwater near the infiltration basins appears to be controlled by dissolved oxygen concentrations, with high iron concentrations occurring where dissolved oxygen concentrations are low. Pumping bores located near infiltration basins may suffer from iron encrustation problems caused by the mixing of shallow, oxygenated groundwater with water containing higher concentrations of iron from deeper in the aquifer.

  12. Impingement of Deep Mantle-Derived Upwelling Beneath Northern, Subducted Extension of the East Pacific Rise and Palinspastically Restored Cenozoic Mafic Magmatism in Western North America

    Science.gov (United States)

    Rowley, D. B.; Moucha, R.; Forte, A. M.; Mitrovica, J. X.; Simmons, N. A.; Grand, S. P.

    2009-12-01

    Reconstruction of the retrodicted whole mantle flow, based on presently imaged distribution of variations in seismic velocity and its correlation to density (Simmons et al. 2009), over the past 30 Ma, in the North American fixed frame of reference, reveals that the northern, now subducted, extension of the East Pacific Rise is coincident with mantle buoyancy arising from near the core-mantle boundary and extending to the base of the lithosphere (Moucha et al. 2009 GRL, in press). Divergence of the reconstructed flow near the surface is independent of the surface plate(s) and results in predicted geological manifestations distinct from those predicted by traditional plate driven models of flow. Most particularly the retrodicted flow-related dynamic topography results in progressive west to east sweep of surface uplift, that is now centered on the Colorado Plateau (Moucha et al. 2008, 2009 GRL, in press). In addition, and the primary focus of the current study is the relationship between this retrodicted mantle-wide flow and the history of magmatism within the western U.S. and adjacent Mexico. There is a close spatial correlation between the impingement of upwelling with palinspastic restored western North America (McQuarrie and Wernicke, 2005) and onset and distribution of magmatism, particularly of mafic compositions as revealed in the Navdat (www.navdat.org) database. Although often attributed to effects of opening of a slab window (Snyder and Dickinson, 1979, McQuarrie and Oskins, 2008) associated with continued plate-driven separation, this model predicts active mantle flow induced upwelling and divergence resulting in mantle melting that sweeps across east-northeast across southern Basin and Range to the Rio Grande Rift with time and as seen in the distribution of magmatism in this region.

  13. Out of the tropics: the Pacific, Great Basin lakes, and late Pleistocene water cycle in the western United States

    Science.gov (United States)

    Lyle, Mitchell; Heusser, Linda; Ravelo, Christina; Yamamoto, Masanobu; Barron, John; Diffenbaugh, Noah S.; Herbert, Timothy; Andreasen, Dyke

    2012-01-01

    The water cycle in the western U.S. changed dramatically over glacial cycles. In the last 20,000 years, higher precipitation caused desert lakes to form which have since dried out. Higher glacial precipitation is hypothesized to result from a southward shift of Pacific winter storm tracks. We compared Pacific Ocean data to lake levels from the interior west and found that Great Basin lake high stands are older than coastal wet periods at the same latitude. Westerly storms were not the source of high precipitation. Instead, air masses from the tropical Pacific were transported northward, bringing more precipitation into the Great Basin when coastal California was still dry. The changing climate during the deglaciation altered precipitation source regions and strongly affected the regional water cycle.

  14. GEODYNAMICAL MODELING OF CRUSTAL DEFORMATION OF THE NORTH CHINA BLOCK

    Institute of Scientific and Technical Information of China (English)

    LIN Ge; ZHANG Yan-hua; GUO Feng; WANG Yue-jun; FAN Wei-ming

    2001-01-01

    @@ The North China block,the western portion of the Sino-Korean Craton,is rounded by Yanshanian in the north and Qinling-Dabie orogenic belts in the south.The widespread development of extensional basins in this block indicates horizontal extension or continued thinning of a previousely thickened,trnstable lithosphere throughout the Mesozoic.In this paper,we attempt to simulate numerically the geodynamical process of the basin formation by using the mountain-basin evolution system.We assume that the formation of numerous sedimentary basins in the North China block is the result of the crustal extension,which destructs rapidly the previously thickened crust.

  15. Development of basins in the Inner Moray Firth and the North Sea by crustal extension and dextral displacement of the Great Glen Fault

    Science.gov (United States)

    McQuillin, R.; Donato, J. A.; Tulstrup, J.

    1982-08-01

    Reflection seismic data provide evidence that Mesozoic dextral movements along the Great Glen Fault line have had an important influence on the development of the Inner Moray Firth Basin. Geophysical evidence further indicates that deep structure beneath the inner basin is dissimilar to that beneath the outer part and Viking and Central Grabens in the North Sea. Tectonic development of the inner basin can nevertheless be fitted into a pattern of North Sea extensional movements which led to the formation of the graben system with which the major North Sea hydrocarbon resources are associated.

  16. Travertine from Egypt's Western Desert: a terrestrial proxy for North African paleohydrology and paleoclimate during the Quaternary

    Science.gov (United States)

    Jimenez, G.; Crossey, L. J.; Karlstrom, K. E.; Polyak, V. J.; Asmerom, Y.

    2013-12-01

    The 'Green Sahara' pluvial phases that overprinted North African aridity during the Pleistocene are well recognized in tropical and Mediterranean marine records. Comparatively few studies have investigated the terrestrial expression of these pluvials, though, in part because of the paucity of paleohydrology archives in the desert. In this study, we show that travertine in Egypt's Western Desert constitutes a unique terrestrial proxy for the North African hydrologic cycle. In the Western Desert, travertine (defined inclusively as chemically-precipitated continental carbonate) deposits in paleo-oasis springs during times of high hydrologic head. Since head increases as meteoric precipitation falls in southern groundwater recharge areas, large-scale travertine accumulations can record pluvial episode durations as well as their geochemical characteristics. We built a database of new and previously-published U/Th ages from five paleo-oasis areas spanning a north-south gradient through the Western Desert. Integrating this geochronology with stable isotope and 87Sr/86Sr geochemistry of travertine samples, we present a terrestrial record of North African pluvial periods for the last ~650 ka. We show that groundwater sources for travertine remain constant through space and time, implying hydrological similarity between pluvial periods. The timing of travertine deposition is inconsistent over shorter (~10 ka) timescales in the various paleo-oases, though, suggesting that local hydrology may obscure the travertine response to pluvials. However, we observe significant travertine deposition across several areas between approximately 100 to 300 ka, and 450 to 600 ka, with a hiatus in between; we interpret these depositional 'peaks' to correspond with maxima in the 400-ka component of eccentricity. Thus, contrary to prior literature, we find that travertine deposition in the Western Desert, and thus pluvial occurrence, responds to orbitally-paced changes in equatorial insolation

  17. Basin-floor fans in the North Sea: Sequence stratigraphic models vs. sedimentary facies

    Energy Technology Data Exchange (ETDEWEB)

    Shanmugam, G.; Bloch, R.B. [Mobil Research and Development Corp., Dallas, TX (United States); Mitchell, S.M. [Mobil Exploration and Producing US, Inc., Dallas, TX (United States); Beamish, G.W.J.; Shields, K.E. [Mobil North Sea Ltd., London (United Kingdom); Hodgkinson, R.J.; Straume, T.; Syvertsen, S.E. [Mobil Exploration Norway, Inc., Stavanger (Norway); Damuth, J.E. [Univ. of Texas, Arlington, TX (United States)

    1995-04-01

    Examination of nearly 12,000 feet (3658m) of conventional core from Paleogene and Cretaceous deep-water sandstone reservoirs cored in 50 wells in 10 different areas or fields in the North Sea and adjacent regions reveals that these reservoirs are predominantly composed of mass-transport deposits, mainly sandy slumps and sandy debris flows. Sedimentary features indicating slump and debris-flow origin include sand units with sharp upper contacts; slump folds; discordant, steeply dipping layers (up to 60{degrees}); glide planes; shear zones; brecciated clasts; clastic injections; floating mudstone clasts; planar clast fabric; inverse grading of clasts; and moderate-to-high matrix content (5-30%). This model predicts that basin-floor fans are predominantly composed of sand-rich turbidites with laterally extensive, sheetlike geometries. However, calibration of sedimentary facies in our long (400-700 feet) cores with seismic and wire-line-log signatures through several of these basin-floor fans (including the Gryphon-Forth, Frigg, and Faeroe areas) shows that these features are actually composed almost exclusively of mass-transport deposits consisting mainly of slumps and debris flows. Distinguishing deposits of mass-transport processes, such as debris flows, from those of turbidity currents has important implications for predicting reservoir geometry. Debris flows, which have plastic flow rheology, can form discontinuous, disconnected sand bodies that are harder to delineate and less economical to develop than deposits of fluidal turbidity currents, which potentially produce more laterally continuous, interconnected sand bodies. Process sedimentological interpretation of conventional core is commonly critical for determining the true origin and distribution of reservoir sands.

  18. Prevalence of phocine distemper virus specific antibodies: bracing for the next seal epizootic in north-western Europe

    OpenAIRE

    Bodewes, Rogier; Morick, Danny; van de Bildt, Marco WG; Osinga, Nynke; Rubio García, Ana; Sánchez Contreras, Guillermo J; Smits, Saskia L.; Reperant, Leslie AP; Kuiken, Thijs; Osterhaus, Albert DME

    2013-01-01

    In 1988 and 2002, two major phocine distemper virus (PDV) outbreaks occurred in harbour seals (Phoca vitulina) in north-western European coastal waters, causing the death of tens of thousands seals. Here we investigated whether PDV is still circulating among seals of the Dutch coastal waters and whether seals have protective serum-antibodies against PDV. Therefore seal serum samples, collected from 2002 to 2012, were tested for the presence of PDV-neutralizing antibodies. Antibodies were dete...

  19. Mercury in western North America: A synthesis of environmental contamination, fluxes, bioaccumulation, and risk to fish and wildlife

    Science.gov (United States)

    Eagles-Smith, Collin A.; Wiener, James G.; Eckley, Chris S.; Willacker, James J.; Evers, David C.; Marvin-DiPasquale, Mark C.; Obrist, Daniel; Fleck, Jacob; Aiken, George R.; Lepak, Jesse M.; Jackson, Allyson K.; Webster, Jackson; Stewart, Robin; Davis, Jay; Alpers, Charles N.; Ackerman, Josh

    2016-01-01

    Western North America is a region defined by extreme gradients in geomorphology and climate, which support a diverse array of ecological communities and natural resources. The region also has extreme gradients in mercury (Hg) contamination due to a broad distribution of inorganic Hg sources. These diverse Hg sources and a varied landscape create a unique and complex mosaic of ecological risk from Hg impairment associated with differential methylmercury (MeHg) production and bioaccumulation. Understanding the landscape-scale variation in the magnitude and relative importance of processes associated with Hg transport, methylation, and MeHg bioaccumulation requires a multidisciplinary synthesis that transcends small-scale variability. The Western North America Mercury Synthesis compiled, analyzed, and interpreted spatial and temporal patterns and drivers of Hg and MeHg in air, soil, vegetation, sediments, fish, and wildlife across western North America. This collaboration evaluated the potential risk from Hg to fish, and wildlife health, human exposure, and examined resource management activities that influenced the risk of Hg contamination. This paper integrates the key information presented across the individual papers that comprise the synthesis. The compiled information indicates that Hg contamination is widespread, but heterogeneous, across western North America. The storage and transport of inorganic Hg across landscape gradients are largely regulated by climate and land-cover factors such as plant productivity and precipitation. Importantly, there was a striking lack of concordance between pools and sources of inorganic Hg, and MeHg in aquatic food webs. Additionally, water management had a widespread influence on MeHg bioaccumulation in aquatic ecosystems, whereas mining impacts where relatively localized. These results highlight the decoupling of inorganic Hg sources with MeHg production and bioaccumulation. Together the findings indicate that developing

  20. High amphibian diversity related to unexpected environmental values in a biogeographic transitional area in north-western Mexico

    OpenAIRE

    Serrano, J. M.; Berlanga-Robles, C.A.; Ruiz-Luna, A.

    2014-01-01

    Amphibian diversity and distribution patterns in Sinaloa state (north-western Mexico) were assessed from the Global Amphibian Assessment database (GAA-2010). A geographic information system (GIS) was used to evaluate diversity based on distribution maps of 41 species, associated with environmental data. The highest α and γ-diversities were identified in the south-eastern portion of the state, in mountain zones with a warm sub-humid climate, whereas the greatest β-diversity (multiplicative for...

  1. Reassessing the Significance of Firearms in Central Africa: The Case of North-Western Zambia to the 1920s

    OpenAIRE

    Macola, Giacomo

    2010-01-01

    Based on a close examination of European travelogues and the evidence produced in the wake of the formulation of colonial gun policies, this article contends that the significance of firearms in Central Africa in the nineteenth and early twentieth centuries has been unduly played down in the existing literature. The first substantive section of the article charts the movement of the gun frontier in nineteenth-century north-western Zambia. It foregrounds the new technology’s economic and milit...

  2. Mercury in western North America: A synthesis of environmental contamination, fluxes, bioaccumulation, and risk to fish and wildlife.

    Science.gov (United States)

    Eagles-Smith, Collin A; Wiener, James G; Eckley, Chris S; Willacker, James J; Evers, David C; Marvin-DiPasquale, Mark; Obrist, Daniel; Fleck, Jacob A; Aiken, George R; Lepak, Jesse M; Jackson, Allyson K; Webster, Jackson P; Stewart, A Robin; Davis, Jay A; Alpers, Charles N; Ackerman, Joshua T

    2016-10-15

    Western North America is a region defined by extreme gradients in geomorphology and climate, which support a diverse array of ecological communities and natural resources. The region also has extreme gradients in mercury (Hg) contamination due to a broad distribution of inorganic Hg sources. These diverse Hg sources and a varied landscape create a unique and complex mosaic of ecological risk from Hg impairment associated with differential methylmercury (MeHg) production and bioaccumulation. Understanding the landscape-scale variation in the magnitude and relative importance of processes associated with Hg transport, methylation, and MeHg bioaccumulation requires a multidisciplinary synthesis that transcends small-scale variability. The Western North America Mercury Synthesis compiled, analyzed, and interpreted spatial and temporal patterns and drivers of Hg and MeHg in air, soil, vegetation, sediments, fish, and wildlife across western North America. This collaboration evaluated the potential risk from Hg to fish, and wildlife health, human exposure, and examined resource management activities that influenced the risk of Hg contamination. This paper integrates the key information presented across the individual papers that comprise the synthesis. The compiled information indicates that Hg contamination is widespread, but heterogeneous, across western North America. The storage and transport of inorganic Hg across landscape gradients are largely regulated by climate and land-cover factors such as plant productivity and precipitation. Importantly, there was a striking lack of concordance between pools and sources of inorganic Hg, and MeHg in aquatic food webs. Additionally, water management had a widespread influence on MeHg bioaccumulation in aquatic ecosystems, whereas mining impacts where relatively localized. These results highlight the decoupling of inorganic Hg sources with MeHg production and bioaccumulation. Together the findings indicate that developing

  3. Ethnomedicine of the Kagera Region, north western Tanzania. Part 3: plants used in traditional medicine in Kikuku village, Muleba District

    OpenAIRE

    Moshi Mainen J; Otieno Donald F; Weisheit Anke

    2012-01-01

    Abstract Background The Kagera region of north western Tanzania has a rich culture of traditional medicine use and practice. Traditional medicines are the mainstay of healthcare in this region and are known to support the management of many illnesses such as malaria, bacterial infections, epilepsy, gynecological problems and others. However, most of the plants being used have either not been documented or evaluated for safety and efficacy or both. This study, the sixth of an ongoing series, r...

  4. Re-Evaluating Geothermal Potential with GIS Methods and New Data: Williston Basin, North Dakota

    Science.gov (United States)

    Crowell, A. M.; Gosnold, W. D.; UND Geothermal Laboratory

    2011-12-01

    The University of North Dakota Geothermal Laboratory is working on the National Geothermal Data Aggregation project in conjunction with Southern Methodist University (SMU) and other partners, and funded by the Department of Energy to collect data for exploration and utilization of resources for geothermal power production. We have examined 10,951 wells in the Williston Basin to determine accurate methods for estimating power extraction potential in a sedimentary basin. The calculations we used involved defining the area of wells within designated ranges and calculating the geothermal fluid reservoir volume using porosity data from the North Dakota Geological Survey Wilson M. Laird Core Library. We defined the parameters for our calculations as: bottom-hole temperature (BHT), formation thickness data, surface area of the polygon around wells within the temperature range, and porosity data. The wells in each formation with a BHT over 90°C were imported into ArcGIS, buffered to 1.6 kilometers from centroid, and outlined with a polygon feature to define the surface area. We then included average formation thickness to determine an approximate volume for ten water and rock reservoirs. In calculating this available energy the following three assumptions were made; that 1/1000 of the water volume is available to use per year, that the temperature is lowered to 50°C during electrical power production, and that the efficiency of the binary power plant utilized is 14%. The estimated recoverable energy in the volume of rock containing geothermal fluids by temperature range is as follows: 1.32 x 108 MW for 90°-100° C, 1.92 x 108 MW for 100°-110° C, 2.15 x 108 MW for 110°-120° C, 2.4 x 108 MW for 120°-130° C, 1.4 x 108 MW for 130°-140° C, 4.95 x 107 MW for 140°-150° C, and 3.67 x 107 MW for 150° C and up.

  5. Reconstructing multiple arc-basin systems in the Altai-Junggar area (NW China): Implications for the architecture and evolution of the western Central Asian Orogenic Belt

    Science.gov (United States)

    Li, Di; He, Dengfa; Tang, Yong

    2016-05-01

    The Altai-Junggar area in northwestern China is a critical region to gain insights on the tectonic framework and geological evolution of the western Central Asian Orogenic Belt (CAOB). In this study, we report results from integrated geological, geochemical and geophysical investigations on the Wulungu Depression of the Junggar Basin to determine the basement nature of the basin and understand its amalgamation history with the Chinese Altai, within the broad tectonic evolution of the Altai-Junggar area. Based on borehole and seismic data, the Wulungu Depression is subdivided into two NW-trending tectonic units (Suosuoquan Sag and Hongyan High) by southward-vergent thrust faults. The Suosuoquan Sag consists of the Middle-Late Devonian basaltic andesite, andesite, dacite, tuff, tuffaceous sandstone and tuffite, and the overlying Early Carboniferous volcano-sedimentary sequence with lava flows and shallow marine sediments from a proximal juvenile provenance (zircon εHf(t) = 6.0-14.9), compared to the Late Carboniferous andesite and rhyolite in the Hongyan High. Zircon SIMS U-Pb ages for dacites and andesites indicate that these volcanics in the Suosuoquan Sag and Hongyan High erupted at 376.3 Ma and 313.4 Ma, respectively. The Middle-Late Devonian basaltic andesites from well LC1 are calc-alkaline and exhibit primitive magma-like MgO contents (7.9-8.6%) and Mg# values (66-68), with low initial 87Sr/86Sr (0.703269-0.704808) and positive εNd(t) values (6.6-7.6), and relatively high Zr abundance (98.2-116.0 ppm) and Zr/Y ratios (5.1-5.4), enrichment in LREEs and LILEs (e.g., Th and U) and depletion in Nb, Ta and Ti, suggesting that they were probably derived from a metasomatized depleted mantle in a retro-arc extensional setting. The well LC1 andesitic tuffs, well L8 dacites, well WL1 dacitic tuffs and well L5 andesites belong to calc-alkaline and metaluminous to peraluminous (A/CNK = 0.8-1.7) series, and display low Mg# values (35-46) and variably positive εNd(t) (4

  6. Disruption of ecosystem processes in western North America by invasive species

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Dukes

    2004-09-01

    Full Text Available Many ecosystems of western North America have been dramatically changed by non-native species. Here, we review ecological impacts of 56 plant, animal, fungus, and protist species that were brought to this region by humans. We discuss characteristics of invasive species that can lead to major ecosystem impacts, and explore how invasive species alter many different attributes of ecosystems. Specifically, we include examples of invasive species that affect geomorphology, fire regimes, hydrology, microclimate, atmospheric composition, nutrient cycling, and productivity. Finally, we review the direct consequences of biological invasions for some native species. We summarize examples from this paper in Appendix 1. Our examples illustrate how, as invasive species have become dominant across large areas of western North America's grassland, shrubland, dune, riparian, and estuarine ecosystems, the properties and functioning of these systems have changed. To date, some systems in this region, such as its forests, remain relatively unaffected by invasive species. However, recent attacks of forest pathogens highlight the potential vulnerability of these ecosystemsMuchos ecosistemas de Norteamérica occidental han cambiado dramáticamente a causa del efecto producido por especies no autóctonas. Aquí se muestra una revisión del impacto ecológico producido por 56 especies diferentes de plantas, animales y hongos, y especies de protistas que fueron traídos a esta región por humanos. Discutimos las características de las especies invasoras que pueden producir un gran impacto en el ecosistema, y exploramos cómo las especies invasoras pueden alterar de forma muy diferente los atributos de un ecosistema. Específicamente, incluimos ejemplos de especies invasoras que afectan a la geomorfología, a los regímenes del fuego, a la hidrología, al microclima, a la composición atmosférica, al ciclo de nutrientes, y a la productividad. Finalmente, revisamos las

  7. Pre-bomb marine reservoir ages in the western north Pacific: Preliminary result on Kyoto University collection

    Energy Technology Data Exchange (ETDEWEB)

    Yoneda, Minoru E-mail: myoneda@nies.go.jp; Kitagawa, Hiroyuki; Plicht, Johannes van der; Uchida, Masao; Tanaka, Atsushi; Uehiro, Takashi; Shibata, Yasuyuki; Morita, Masatoshi; Ohno, Terufumi

    2000-10-01

    The calibration of radiocarbon dates on marine materials involves a global marine calibration with regional corrections. The marine reservoir ages in the Western North Pacific have not been discussed, while it is quite important to determine the timing of palaeo-environmental changes as well as archaeological interpretation around this region. The lack of adequate collection of the pre-bomb shell from western north Pacific was the biggest problem. Recently we had a chance to examine specimens from an old shell collection stored in Kyoto University, including shell specimens from Japan, Korea, Taiwan and the Micronesia of 1920s and 1930s. We explored the possibility for usage of specimen without clear evidence of live collection by measuring 30 apparent radiocarbon ages of pre-bomb mollusk shells from 18 sites in Western North Pacific. The preliminary results showed several discrepancies with previously reported results and with each other. We have to carefully select the shell specimen that has biological signs such as articulating fulcrum. In order to exploit this big resource of pre-bomb shell collection, the new technique to distinguish fossils from live collected samples should be developed by using chemical and physical methods.

  8. Interdecadal modulation on the relationship between ENSO and typhoon activity during the late season in the western North Pacific

    Science.gov (United States)

    Zhao, Haikun; Wang, Chunzai

    2016-07-01

    The present study identifies an interdecadal modulation of the Pacific decadal oscillation (PDO) on the relationship between El Niño-Southern oscillation (ENSO) and typhoon activity during the late season (October-December) in the western North Pacific. The PDO is uncorrelated with ENSO during the warm phase of 1979-1997, while the PDO is positively correlated with ENSO during the cold phase of 1998-2012. Further analyses show that the warm phase is associated with the reduced ENSO-typhoon activity relationship and more typhoons, whereas the cold phase is corresponded to the enhanced ENSO-typhoon activity relationship and fewer typhoons. These variations are mainly manifested by a significant difference of typhoon activity in the southeastern part of the western North Pacific. Moreover, the change of ENSO-typhoon relationship is largely due to changes in large-scale environmental conditions especially from low-level vorticity and vertical wind shear between the two phases, which are related to the changes in tropical Indo-Pacific sea surface temperature. The study implies that the phase of the PDO should be taken into account when ENSO is used as a predictor for predicting typhoon activity in the western North Pacific.

  9. INVENTORY AND PLANT DIVERSITY CONSERVATION IN THE NORTH-WESTERN PART OF THE GREAT CAUCASUS

    Directory of Open Access Journals (Sweden)

    Litvinskaya S. A.

    2012-11-01

    Full Text Available The problems of floristic inventory within four floristic areas are underlined, namely for Western Ciscaucasia, Western Caucasus, Northwest, and the Western Transcaucasia. The issue questions towards taxonomy, species protection, devastation in ecosystems, and adventizion of vegetation are considered.

  10. Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Bandana Devi

    2013-05-01

    Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as a major sink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied under different plantation forest ecosystems comprising of eight different tree species: Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnusnitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57±48.99tha-1 and below ground (42.47±10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera(118.37±1.49 tha-1 and minimum (36.50±9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86±10.34 tha-1 in Alnus nitida, and minimum (170.83±20.60 tha-1 in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79±2.0 tha-1. Carbon sequestration (7.91±3.4 tha-1 and CO2 mitigation potential (29.09±12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions for sustainable management of fragile hilly ecosystem.

  11. The distribution of thiamin and pyridoxine in the western tropical North Atlantic Amazon River plume

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    Laila Pualani Barada

    2013-03-01

    Full Text Available B-vitamins are recognized as essential organic growth factors for many organisms, although little is known about their abundance and distribution in marine ecosystems. Despite their metabolic functions regulating important enzymatic reactions, the methodology to directly measure different B-vitamins in aquatic environments has only recently been developed. Here, we present the first direct measurements of two B-vitamins, thiamin (B1 and pyridoxine (B6, in the Amazon River plume-influenced Western Tropical North Atlantic (WTNA Ocean, an area known to have high productivity, carbon (C and dinitrogen (N2 fixation, and C sequestration. The vitamins B1 and B6 ranged in concentrations from undetectable to 230 pM and 40 pM, respectively. Significantly higher concentrations were measured in the surface plume water at some stations and variation with salinity was observed, suggesting a possible riverine influence on those B-vitamins. The influences of vitamins B1 and B6 on biogeochemical processes such as C and N2 fixation were investigated using a linear-regression model that indicated that the availability of those organic factors could affect these rates in the WTNA. In fact, significant increases in C fixation and N2 fixation were observed with increasing vitamin B1 concentrations at some low and mesohaline stations (stations 9.1 and 1; p value <0.017 and <0.03, respectively. N2 fixation was also found to have a significant positive correlation with B1 concentrations at station 1 (p value = 0.029, as well as vitamin B6 at station 9.1 (p value <0.017. This work suggests that there can be a dynamic interplay between essential biogeochemical rates (C and N2 fixation and B-vitamins, drawing attention to potential roles of B-vitamins in ecosystem dynamics, community structure, and global biogeochemistry.

  12. Upper Mantle Discontinuity Structure Beneath the Western Atlantic Ocean and Eastern North America from SS Precursors

    Science.gov (United States)

    Schmerr, N. C.; Beghein, C.; Kostic, D.; Baldridge, A. M.; West, J. D.; Nittler, L. R.; Bull, A. L.; Montesi, L.; Byrne, P. K.; Hummer, D. R.; Plescia, J. B.; Elkins-Tanton, L. T.; Lekic, V.; Schmidt, B. E.; Elkins, L. J.; Cooper, C. M.; ten Kate, I. L.; Van Hinsbergen, D. J. J.; Parai, R.; Glass, J. B.; Ni, J.; Fuji, N.; McCubbin, F. M.; Michalski, J. R.; Zhao, C.; Arevalo, R. D., Jr.; Koelemeijer, P.; Courtier, A. M.; Dalton, H.; Waszek, L.; Bahamonde, J.; Schmerr, B.; Gilpin, N.; Rosenshein, E.; Mach, K.; Ostrach, L. R.; Caracas, R.; Craddock, R. A.; Moore-Driskell, M. M.; Du Frane, W. L.; Kellogg, L. H.

    2015-12-01

    Seismic discontinuities within the mantle arise from a wide range of mechanisms, including changes in mineralogy, major element composition, melt content, volatile abundance, anisotropy, or a combination of the above. In particular, the depth and sharpness of upper mantle discontinuities at 410 and 660 km depth are attributed to solid-state phase changes sensitive to both mantle temperature and composition, where regions of thermal heterogeneity produce topography and chemical heterogeneity changes the impedance contrast across the discontinuity. Seismic mapping of this topography and sharpness thus provides constraint on the thermal and compositional state of the mantle. The EarthScope USArray is providing unprecedented access to a wide variety of new regions previously undersampled by the SS precursors. This includes the boundary between the oceanic plate in the western Atlantic Ocean and continental margin of eastern North America. Here we use a seismic array approach to image the depth, sharpness, and topography of the upper mantle discontinuities, as well as other possible upper mantle reflectors beneath this region. This array approach utilizes seismic waves that reflect off the underside of a mantle discontinuity and arrive several hundred seconds prior to the SS seismic phase as precursory energy. In this study, we collected high-quality broadband data SS precursors data from shallow focus (4th root vespagrams to enhance the SS precursors and determine how they sample the mantle. Our data show detection of localized structure on the discontinuity boundaries as well as additional horizons, such as the X-discontinuity and a potential reflection from a discontinuity near the depth of the lithosphere-asthenosphere boundary. These structures are related to the transition from predominantly old ocean lithosphere to underlying continental lithosphere, as while deeper reflectors are associated with the subduction of the ancient Farallon slab. A comparison of the

  13. DIFFERENCES AMONG DIFFERENT DATABASES IN THE NUMBER OF TROPICAL CYCLONES FORMING OVER THE WESTERN NORTH PACIFIC

    Institute of Scientific and Technical Information of China (English)

    WU Sheng-an; KONG Hai-jiang; WU hui

    2010-01-01

    As shown in comparisons of the characteristics of inter-annual and inter-decadal variability and periodical changes in the number of tropical cyclones forming over the western North Pacific by three major forecast centers,i.e.China Meteorological Administration (CMA),Regional Specialized Meteorological Center of Tokyo (JMA) and Joint Typhoon Warning Center (JTWC) of Guam,there are the following important points.(1) Climatology of tropical cyclone (TC) or typhoon (TC on the intensity of TS or stronger) shows some difference in tropical cyclone frequency among the centers,which is more notable with TC than with typhoon.Both of them are more at the database of CMA than at those of the other two centers.(2) The difference is too significant to ignore in the inter-annual variability of tropical cyclone frequency between CMA and JTWC,which mainly results from the obvious difference in the inter-annual variability of the number of generated tropical depression (TD) between the two databases.The difference is small in the inter-annual variability of TS formations among all the three databases,and consistence is good between JMA and CMA or JTWC.(3) Though differences are not significant in the periodical variation of TC formations between CMA and JTWC,they are markedly apart in the inter-decadal variability,which is mainly shown by an anti-phase during the 1990s.(4) Non-homogeneity may exist around the late stage of the 1960s in the data of tropical cyclone frequency.

  14. Age and Growth of the Dusky Shark, Carcharhinus obscurus, in the Western North Pacific Ocean

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    Shoou-Jeng Joung

    2015-01-01

    Full Text Available Age and growth of the dusky shark, Carcharhinus obscurus, in the western North Pacific Ocean was estimated based on 434 specimens (213 females and 256 males collected between September 2002 and November 2003 at the Nanfanao fish market, in northeastern Taiwan. Sex-specific relationships between body weight (W and total length (TL were estimated as follows: W = 2.03 _ 10-6TL3.216 (n = 209, p < 0.01 for females and W = 8.01 _ 10-6TL2.957 (n = 294, p < 0.01 for males. The relationship between TL and the vertebral centrum radius (R for both sexes _ data was described using the following equation TL = 14.74 + 20.31R (n = 399, p < 0.01. Growth band pairs (including translucent and opaque bands in precaudal vertebrae were determined to form once annually, based on centrum edge analysis and verified by statistical analysis. The maximum number of growth band pairs was 29 for females and 24 for males. The Robertson growth function best fit the observed length-at-age data. Sex-specific growth equations were not significantly different; thus, the combined growth parameters for both sexes were estimated as: asymptotic length (L∞(L∞ = 369.4 cm TL, b = 0.912, growth coefficient (kR = 0.126 yr-1 (n = 385, p < 0.01. Age at maturity was estimated to be 16.6 yrs for females and 15.5 yrs for males.

  15. Microbes in mercury-enriched geothermal springs in western North America.

    Science.gov (United States)

    Geesey, Gill G; Barkay, Tamar; King, Sue

    2016-11-01

    Because geothermal environments contain mercury (Hg) from natural sources, microorganisms that evolved in these systems have likely adapted to this element. Knowledge of the interactions between microorganisms and Hg in geothermal systems may assist in understanding the long-term evolution of microbial adaptation to Hg with relevance to other environments where Hg is introduced from anthropogenic sources. A number of microbiological studies with supporting geochemistry have been conducted in geothermal systems across western North America. Approximately 1 in 5 study sites include measurements of Hg. Of all prokaryotic taxa reported across sites with microbiological and accompanying physicochemical data, 42% have been detected at sites in which Hg was measured. Genes specifying Hg reduction and detoxification by microorganisms were detected in a number of hot springs across the region. Archaeal-like sequences, representing two crenarchaeal orders and one order each of the Euryarchaeota and Thaumarchaeota, dominated in metagenomes' MerA (the mercuric reductase protein) inventories, while bacterial homologs were mostly found in one deeply sequenced metagenome. MerA homologs were more frequently found in metagenomes of microbial communities in acidic springs than in circumneutral or high pH geothermal systems, possibly reflecting higher bioavailability of Hg under acidic conditions. MerA homologs were found in hot springs prokaryotic isolates affiliated with Bacteria and Archaea taxa. Acidic sites with high Hg concentrations contain more of Archaea than Bacteria taxa, while the reverse appears to be the case in circumneutral and high pH sites with high Hg concentrations. However, MerA was detected in only a small fraction of the Archaea and Bacteria taxa inhabiting sites containing Hg. Nevertheless, the presence of MerA homologs and their distribution patterns in systems, in which Hg has yet to be measured, demonstrates the potential for detoxification by Hg reduction

  16. Climate Warming and Seasonal Precipitation Change Interact to Limit Species Distribution Shifts across Western North America.

    Science.gov (United States)

    Harsch, Melanie A; HilleRisLambers, Janneke

    2016-01-01

    Using an extensive network of occurrence records for 293 plant species collected over the past 40 years across a climatically diverse geographic section of western North America, we find that plant species distributions were just as likely to shift upwards (i.e., towards higher elevations) as downward (i.e., towards lower elevations)-despite consistent warming across the study area. Although there was no clear directional response to climate warming across the entire study area, there was significant region- to region- variation in responses (i.e. from as many as 73% to as few as 32% of species shifting upward). To understand the factors that might be controlling region-specific distributional shifts of plant species, we explored the relationship between the direction of change in distribution limits and the nature of recent climate change. We found that the direction that distribution limits shifted was explained by an interaction between the rate of change in local summer temperatures and seasonal precipitation. Specifically, species were more likely to shift upward at their upper elevational limit when minimum temperatures increased and snowfall was unchanging or declined at slower rates (<0.5 mm/year). This suggests that both low temperature and water availability limit upward shifts at upper elevation limits. By contrast, species were more likely to shift upwards at their lower elevation limit when maximum temperatures increased, but also shifted upwards under conditions of cooling temperatures when precipitation decreased. This suggests increased water stress may drive upward shifts at lower elevation limits. Our results suggest that species' elevational distribution shifts are not predictable by climate warming alone but depend on the interaction between seasonal temperature and precipitation change.

  17. Climate Warming and Seasonal Precipitation Change Interact to Limit Species Distribution Shifts across Western North America.

    Directory of Open Access Journals (Sweden)

    Melanie A Harsch

    Full Text Available Using an extensive network of occurrence records for 293 plant species collected over the past 40 years across a climatically diverse geographic section of western North America, we find that plant species distributions were just as likely to shift upwards (i.e., towards higher elevations as downward (i.e., towards lower elevations-despite consistent warming across the study area. Although there was no clear directional response to climate warming across the entire study area, there was significant region- to region- variation in responses (i.e. from as many as 73% to as few as 32% of species shifting upward. To understand the factors that might be controlling region-specific distributional shifts of plant species, we explored the relationship between the direction of change in distribution limits and the nature of recent climate change. We found that the direction that distribution limits shifted was explained by an interaction between the rate of change in local summer temperatures and seasonal precipitation. Specifically, species were more likely to shift upward at their upper elevational limit when minimum temperatures increased and snowfall was unchanging or declined at slower rates (<0.5 mm/year. This suggests that both low temperature and water availability limit upward shifts at upper elevation limits. By contrast, species were more likely to shift upwards at their lower elevation limit when maximum temperatures increased, but also shifted upwards under conditions of cooling temperatures when precipitation decreased. This suggests increased water stress may drive upward shifts at lower elevation limits. Our results suggest that species' elevational distribution shifts are not predictable by climate warming alone but depend on the interaction between seasonal temperature and precipitation change.

  18. Morphological variability of Fraxinus angustifolia Vahl in the north-western Balkans

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    Kristjan Jarni

    2011-08-01

    Full Text Available Fraxinus angustifolia Vahl is a species native in the north-western Balkans, where it has a divided range. Most of its range is located in flood-prone riparian sites in the Pannonian plain but the species is also found on humid sites along some rivers in the Submediterranean region. We analysed morphologic variation within and between five populations (14 trees/population located in the Subpannonian and Submediterranean region of Slovenia. Thirty two characters were assessed on ca. 80 leaves from each tree which were divided depending on exposure to sunlight (sun and shade leaves, and 8 traits on each fruit (ca. 50 fruits/tree. A hierarchically designed experiment using analysis of variance confirmed the significant contribution of all the analysed hierarchical levels of variation to the total variation. The results show that the differences between the trees in a single population are the greatest factor of variability of leaves, followed by differences between populations and differences which are the result of variation in exposure to sunlight. Leaves in shade positions are typically larger than those in sunny positions, and they have broader and shorter-pointed leaflets; in this feature they are very similar to the leaves of F. excelsior. Stepwise discriminant analysis showed that the traits which refer to the leaflet number and length are the best differentiating traits between individual populations. The Submediterranean population Dragonja stands out with the smallest leaves and the population Lijak from the same region is the most similar to Dragonja for most morphological traits. In general, phenotypic differences between the Subpannonian and the Submediterranean populations of F. angustifolia are minor and indistinct. Based on the differences ascertained by the study, we can only confirm the presence of F. angustifolia subsp. oxycarpa (Bieb. ex Willd. Franco et Rocha Alfonso in this part of its natural range.

  19. Reexamination of tropical cyclone heat potential in the western North Pacific

    Science.gov (United States)

    Wada, Akiyoshi

    2016-06-01

    Tropical cyclone heat potential (TCHP), a measure of the oceanic heat content from the surface to the 26°C isotherm depth, has been widely used for tropical cyclone (TC) forecasting and climatological studies. This study reexamines TCHP and the relation to TCs in the western North Pacific in view of the importance of the oceanic reference isothermal depth. Original TCHP is not applicable around the Kuroshio and Kuroshio Extension regions because the value is zero where sea surface temperature is below 26°C. Therefore, this study proposes an improved version of TCHP as new TCHP under relatively weak baroclinic conditions in the atmospheric environment during the TC season from July to November. The alternative oceanic reference isothermal temperature (TRef24) used to calculate new TCHP is determined based on 2 m dew point temperature or 24°C when it is lower than 24°C. We examine the relationship between TCHPs and changes in best track central pressures during the previous 6 h from 2002 to 2012. Relatively high new TCHP is associated with deep oceanic isotherm depth and the decrease in TRef24 around the Kuroshio region from September to November. Case studies for Typhoons Maemi (2003), Songda (2004), and Roke (2011) reveal that TCs could intensify/redevelop around the Ryukyu Islands over warm eddies revealed by high new TCHP, where original TCHP is relatively low. The results indicate that new TCHP can be a metric for TC intensification caused by wind-induced surface heat exchange processes associated with atmospheric temperature and moisture near the surface and upper ocean stratification.

  20. Climate Warming and Seasonal Precipitation Change Interact to Limit Species Distribution Shifts across Western North America

    Science.gov (United States)

    Harsch, Melanie A.; HilleRisLambers, Janneke

    2016-01-01

    Using an extensive network of occurrence records for 293 plant species collected over the past 40 years across a climatically diverse geographic section of western North America, we find that plant species distributions were just as likely to shift upwards (i.e., towards higher elevations) as downward (i.e., towards lower elevations)–despite consistent warming across the study area. Although there was no clear directional response to climate warming across the entire study area, there was significant region- to region- variation in responses (i.e. from as many as 73% to as few as 32% of species shifting upward). To understand the factors that might be controlling region-specific distributional shifts of plant species, we explored the relationship between the direction of change in distribution limits and the nature of recent climate change. We found that the direction that distribution limits shifted was explained by an interaction between the rate of change in local summer temperatures and seasonal precipitation. Specifically, species were more likely to shift upward at their upper elevational limit when minimum temperatures increased and snowfall was unchanging or declined at slower rates (<0.5 mm/year). This suggests that both low temperature and water availability limit upward shifts at upper elevation limits. By contrast, species were more likely to shift upwards at their lower elevation limit when maximum temperatures increased, but also shifted upwards under conditions of cooling temperatures when precipitation decreased. This suggests increased water stress may drive upward shifts at lower elevation limits. Our results suggest that species’ elevational distribution shifts are not predictable by climate warming alone but depend on the interaction between seasonal temperature and precipitation change. PMID:27447834

  1. The Early Mesozoic volcanic arc of western North America in northeastern Mexico

    Science.gov (United States)

    Barboza-Gudiño, José Rafael; Orozco-Esquivel, María Teresa; Gómez-Anguiano, Martín; Zavala-Monsiváis, Aurora

    2008-02-01

    Volcanic successions underlying clastic and carbonate marine rocks of the Oxfordian-Kimmeridgian Zuloaga Group in northeastern Mexico have been attributed to magmatic arcs of Permo-Triassic and Early Jurassic ages. This work provides stratigraphic, petrographic geochronological, and geochemical data to characterize pre-Oxfordian volcanic rocks outcropping in seven localities in northeastern Mexico. Field observations show that the volcanic units overlie Paleozoic metamorphic rocks (Granjeno schist) or Triassic marine strata (Zacatecas Formation) and intrude Triassic redbeds or are partly interbedded with Lower Jurassic redbeds (Huizachal Group). The volcanic rocks include rhyolitic and rhyodacitic domes and dikes, basaltic to andesitic lava flows and breccias, and andesitic to rhyolitic pyroclastic rocks, including breccias, lapilli, and ashflow tuffs that range from welded to unwelded. Lower-Middle Jurassic ages (U/Pb in zircon) have been reported from only two studied localities (Huizachal Valley, Sierra de Catorce), and other reported ages (Ar/Ar and K-Ar in whole-rock or feldspar) are often reset. This work reports a new U/Pb age in zircon that confirms a Lower Jurassic (193 Ma) age for volcanic rocks exposed in the Aramberri area. The major and trace element contents of samples from the seven localities are typical of calc-alkaline, subduction-related rocks. The new geochronological and geochemical data, coupled with the lithological features and stratigraphic positions, indicate volcanic rocks are part of a continental arc, similar to that represented by the Lower-Middle Jurassic Nazas Formation of Durango and northern Zacatecas. On that basis, the studied volcanic sequences are assigned to the Early Jurassic volcanic arc of western North America.

  2. Carbon allocation, sequestration and carbon dioxide mitigation under plantation forests of north western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Bandana Devi

    2013-07-01

    Full Text Available The organic carbon and soils of the world comprise bulk of the terrestrial carbon and serve as amajorsink and source of atmospheric carbon. Increasing atmospheric concentrations of green house gases may be mitigated by increasing carbon sequestration in vegetation and soil. The study attempted to estimate biomass production and carbon sequestration potential of different plantation ecosystems in north western Himalaya, India. Biomass, carbon density of biomass, soil, detritus, carbon sequestration and CO2 mitigation potential were studied underdifferent plantation forest ecosystems comprising of eight different tree species viz. Quercus leucotrichophora, Pinus roxburghii, Acacia catechu, Acacia mollissima, Albizia procera, Alnus nitida, Eucalyptus tereticornis and Ulmus villosa. Above (185.57 ą 48.99 tha-1 and below ground (42.47 ą 10.38 tha-1 biomass was maximum in Ulmus villosa. The vegetation carbon density was maxium in Albizia procera (118.37 ą 1.49 tha-1 and minimum (36.50 ą 9.87 tha-1 in Acacia catechu. Soil carbon density was maximum (219.86ą 10.34 tha-1 in Alnus nitida, and minimum (170.83ą 20.60 tha-1in Pinus roxburghii. Detritus was higher in Pinus roxburghii (6.79 ą 2.0 tha-1. Carbon sequestration (7.91ą 3.4 tha-1 and CO2 mitigation potential (29.09 ą 12.78 tha-1 was maximum in Ulmus villosa. Pearson correlation matrix revealed significant positive relationship of ecosystem carbon with plantation biomass, soil carbon and CO2 mitigation potential. With the emerging threat of climate change, such assessment of forest and soil carbon inventory would allow to devise best land management and policy decisions forsustainable management of fragile hilly ecosystem. 

  3. Microbes in mercury-enriched geothermal springs in western North America.

    Science.gov (United States)

    Geesey, Gill G; Barkay, Tamar; King, Sue

    2016-11-01

    Because geothermal environments contain mercury (Hg) from natural sources, microorganisms that evolved in these systems have likely adapted to this element. Knowledge of the interactions between microorganisms and Hg in geothermal systems may assist in understanding the long-term evolution of microbial adaptation to Hg with relevance to other environments where Hg is introduced from anthropogenic sources. A number of microbiological studies with supporting geochemistry have been conducted in geothermal systems across western North America. Approximately 1 in 5 study sites include measurements of Hg. Of all prokaryotic taxa reported across sites with microbiological and accompanying physicochemical data, 42% have been detected at sites in which Hg was measured. Genes specifying Hg reduction and detoxification by microorganisms were detected in a number of hot springs across the region. Archaeal-like sequences, representing two crenarchaeal orders and one order each of the Euryarchaeota and Thaumarchaeota, dominated in metagenomes' MerA (the mercuric reductase protein) inventories, while bacterial homologs were mostly found in one deeply sequenced metagenome. MerA homologs were more frequently found in metagenomes of microbial communities in acidic springs than in circumneutral or high pH geothermal systems, possibly reflecting higher bioavailability of Hg under acidic conditions. MerA homologs were found in hot springs prokaryotic isolates affiliated with Bacteria and Archaea taxa. Acidic sites with high Hg concentrations contain more of Archaea than Bacteria taxa, while the reverse appears to be the case in circumneutral and high pH sites with high Hg concentrations. However, MerA was detected in only a small fraction of the Archaea and Bacteria taxa inhabiting sites containing Hg. Nevertheless, the presence of MerA homologs and their distribution patterns in systems, in which Hg has yet to be measured, demonstrates the potential for detoxification by Hg reduction

  4. Isolation of Balamuthia mandrillaris from soil samples in North-Western Iran.

    Science.gov (United States)

    Niyyati, Maryam; Karamati, Seyed Ahmad; Lorenzo Morales, Jacob; Lasjerdi, Zohreh

    2016-02-01

    Balamuthia mandrillaris is an opportunistic free-living amoebae (FLA) which has been reported as the causative agent of the fatal Balamuthia amoebic encephalitis (BAE). Currently, the transmission dynamics of this pathogen remain poorly understood although the organism has been associated with soils, and thus, soil exposure has been identified as a risk factor for this pathogenic amoeba. Nevertheless, environmental isolation of B. mandrillaris is a rare event and strains of this amoebic species have been isolated from soil and dust sources only in seven previous reports (Iran, Mexico, USA, Peru, Costa Rica, Guinea Bissau, and Jamaica). In Iran, a previous study reported the isolation of B. mandrillaris from dust collected in the city of Tehran and free of known infectious involvement. Therefore, in this work, 55 soil samples collected from public and recreational areas of East Azerbaijan, North-Western Iran, were investigated for the presence of this pathogen. Samples were cultured in 2% non-nutrient agar plates and were monitored for the presence of B. mandrillaris-like trophozoites and/or cysts. Those samples that were positive for these amoebae by microscopic criteria were then confirmed by PCR amplification and DNA sequencing of the mitochondrial 16S ribosomal DNA (rDNA) of B. mandrillaris. The obtained results revealed the presence of this emerging pathogen in 5 of 55 samples included in the study. Homology analysis of the obtained DNA sequences revealed high similarity with previously isolated strains from clinical and environmental sources. To the best of our knowledge, this is the first report on the isolation of B. mandrillaris from soil sources in Iran related to human activity and the second time that this pathogen is isolated from the environment in this country.

  5. Fluid and gas migration in the North German Basin: fluid inclusion and stable isotope constraints

    Science.gov (United States)

    Lüders, Volker; Reutel, Christian; Hoth, Peer; Banks, David A.; Mingram, Birgit; Pettke, Thomas

    2005-12-01

    Fluid inclusions have been studied in minerals infilling fissures (quartz, calcite, fluorite, anhydrite) hosted by Carboniferous and Permian strata from wells in the central and eastern part of the North German Basin in order to decipher the fluid and gas migration related to basin tectonics. The microthermometric data and the results of laser Raman spectroscopy reveal compelling evidence for multiple events of fluid migration. The fluid systems evolved from a H2O-NaCl±KCl type during early stage of basin subsidence to a H2O-NaCl-CaCl2 type during further burial. Locally, fluid inclusions are enriched in K, Cs, Li, B, Rb and other cations indicating intensive fluid-rock interaction of the saline brines with Lower Permian volcanic rocks or sediments. Fluid migration through Carboniferous sediments was often accompanied by the migration of gases. Aqueous fluid inclusions in quartz from fissures in Carboniferous sedimentary rocks are commonly associated with co-genetically trapped CH4-CO2 inclusions. P-T conditions estimated, via isochore construction, yield pressure conditions between 620 and 1,650 bar and temperatures between 170 and 300°C during fluid entrapment. The migration of CH4-rich gases within the Carboniferous rocks can be related to the main stage of basin subsidence and stages of basin uplift. A different situation is recorded in fluid inclusions in fissure minerals hosted by Permian sandstones and carbonates: aqueous fluid inclusions in calcite, quartz, fluorite and anhydrite are always H2O-NaCl-CaCl2-rich and show homogenization temperatures between 120 and 180°C. Co-ge