Sample records for basin western north

  1. Seasonal forecasting of intense tropical cyclones over the North Atlantic and the western North Pacific basins

    Choi, Woosuk; Ho, Chang-Hoi; Jin, Chun-Sil; Kim, Jinwon; Feng, Song; Park, Doo-Sun R.; Schemm, Jae-Kyung E.


    Intense tropical cyclones (TCs) accompanying torrential rain and powerful wind gusts often cause substantial socio-economic losses in the regions around their landfall. This study analyzes intense TCs in the North Atlantic (NA) and the western North Pacific (WNP) basins during the period 1982-2013. Different intensity criteria are used to define intense TCs for these two basins, category 1 and above for NA and category 3 and above for WNP, because the number of TCs in the NA basin is much smaller than that in the WNP basin. Using a fuzzy clustering method, intense TC tracks in the NA and the WNP basins are classified into two and three representative patterns, respectively. On the basis of the clustering results, a track-pattern-based model is then developed for forecasting the seasonal activities of intense TCs in the two basins. Cross-validation of the model skill for 1982-2013 as well as verification of a forecast for the 2014 TC season suggest that our intense TC model is applicable to operational uses.

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

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


    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

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

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


    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.

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

    Orth, Karin; Phillips, Chris; Hollis, Julie


    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°.

  5. Western Canada Sedimentary Basin competitiveness

    Recent dramatic expansion of the natural gas industry in the Western Canada Sedimentary Basin provided ample proof of the potential of this area for further development of natural gas supply. However, the inherent competitive advantages provided by the Western Canada Sedimentary Basin were said to have been offset by low netback prices resulting in poor producer economics when competitiveness is measured by availability of opportunities to find and develop gas supply at costs low enough to ensure attractive returns. Technology was identified as one of the key elements in improving basin competitiveness, but the greatest potential lies in reduced transportation costs and increased access to North American market centres. 8 figs

  6. An experimental peri-urban basin in North-western France

    Chancibault, K.; Rodriguez, F.; Mosini, M.-L.; Furusho, C.; Bocher, E.; Palaccio, M.; Palma-Lopes, S.; Letellier, L.; Benot, R.; Andrieu, H.


    Basins located in the suburbs, known as peri-urban basins, face a quick land-use change, increasing pollution and flood risks. Being neither urban nor rural basins, they have been left apart by hydrologists. Improving hydrological models taking into account both natural and anthropogenic surfaces and pathways is the objective of the French project AVuPUR. One of the two peri-urban basins chosen for this project is the Chézine basin, located in northwestern France, in the suburbs of Nantes. The Chézine basin is subject to an oceanic climate and has a quite flat topography. Whereas the upstream part of the catchment remains essentially rural, the urbanization is dense in the downstream part and under development in the medium part. The mean urbanization over the basin is about 18%. A first part of the project consists of collecting geographical and hydrological data, followed by a first hydrological data analysis. Then different spatial segmentation methods are tested based on a geomorphological analysis and ultimately hydrological models well adapted for these particular basins will be developed. Nantes Metropole supplies geographical data as roads, buildings, land-use, sewer networks, Digital Elevation Model, etc. They also have monitored Chézine basin since 2001, with a water level recorder and a rain gauge. The outlet, at the water level recorder, defines a 29 km² basin with a 15km long river. During summer 2008, additional recorders were installed, in the medium part of the basin, at the outlet of the rural subcatchment : a rain gauge and a flow meter. This will help to analyse the hydrological behaviour of the catchment, by characterizing the rainfall spatial variability over the basin and by pointing out the rural surface contribution. In autumn 2008, a geophysical experimental study was carried out, using different geophysical methods: ground penetrating radar, DC-electrical resistivity tomography and EM31 electromagnetic profiling method. The aim of this

  7. Trace and major elements in sediments and in porewater from the north western basin of the Mediterranean Sea

    As part of an international and interdisciplinary research program of the European Community (EROS-2000), sediment samples were collected in the north western basin of the Mediterranean Sea in May 1990. In the samples trace and/or major elements were determined to advance the knowledge about the manifestation, sources and cycles of natural and anthropogenic constituents in coastal areas. Three fractions were determined: the porewater fraction which contains all dissolved elements, the leachable fraction which contains all easily exchangeable elements, and the residual fraction which contains the not-exchangeable elements in the sediments. The results show that the investigated area can be separated into five 'sub-areas' which are different in element concentration, leachable fraction and sedimentary composition. Highest concentrations of trace elements are found in sediments closest to the Rhone delta. In summary the Rhone is probably the major source for several (trace)-elements to the Gulf of Lions which is located close to the river mouth of the Rhone. (author). 27 refs.; 15 figs.; 17 tabs

  8. The roles of ENSO on the occurrence of abruptly recurving tropical cyclones over the Western North Pacific Ocean Basin

    N. K. W. Cheung


    Full Text Available The abruptly recurving tropical cyclones over the Western North Pacific Ocean Basin during El Niño and La Niña events are studied. Temporal and spatial variations of these anomalous tracks under different phases of ENSO are shown. The anomalies of the pressure field in relation to ENSO circulation for the occurrence of the abruptly recurving cyclone tracks are investigated using fuzzy method. These are supplemented by wind field analyses. It is found that the occurrence of recurving-left (RL and recurving-right (RR tropical cyclones under the modification of the steering currents, including the re-adjustment of the westerly trough, the expansion or contraction of the sub-tropical high pressure, the intensifying easterly flow and the strengthening of the cross-equatorial flow, can be in El Niño or La Niña events. Evidently, there is a higher chance of occurrence of anomalous tropical cyclone trajectories in El Niño rather than La Niña events, but there is not any pronounced spatial pattern of anomalous tropical cyclone tracks. By analyzing the pressure-field, it is seen RL (RR tropical cyclones tend to occur when the subtropical high pressure is weak (strong in El Niño and La Niña events. More importantly, how the internal force of tropical cyclones changed by the steering current, which relies upon the relative location of tropical cyclones to the re-adjustment of the weather systems, shows when and where RL and RR tropical cyclones occur in El Niño and La Niña events.

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

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


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

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


    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

  11. Palaeomagnetic secular variation and relative field intensity in pleistocene lacustrine sediments in the U.S. great basin as chronologic tools for dating climate in western north America

    Complete text of publication follows. Since the end of the 19th Century when first it was reported that large pluvial lakes formed during the Pleistocene in the U.S. Great Basin (Russell, 1885), the sediments deposited by some of those lakes have been used to study climate in western North America back about 3 m.y. (Smith et al., 1983, Morrison, 1991: many others). That research includes mineralogic, isotopic, geochemical, and sedimentologic data; radiometric dates; lacustrine fossils; volcanic ashes; and a record of long-term behaviour (secular variation) and excursions (Pringle Falls, Laschamp, and Mono Lake) of the palaeomagnetic field. In an attempt to establish an accurate chronology for the palaeoclimate in western North America during the past approximately 50,000 years, I will compare the records of palaeomagnetic directions for Pyramid Lake (the remnant of Lake Lahontan in northwestern Nevada)(Benson et al., 2008), Mono Lake (the remnant of Lake Russell in east-central California)(Lund et al., 1988; Zimmerman et al., 2006), and Searles Lake in the southeastern Great Basin (Liddicoat et al., 2008) with other records of palaeomagnetic field behaviour, especially the relative palaeomagnetic field intensity for the North and South Atlantic oceans (Laj et al., 2000; Stoner et al., 2004). This is possible because large- and small-scale fluctuations occur in the records that are distinctive and often are common to all.

  12. Reserves in western basins

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


    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.

  13. Methane leakage during the evolution of petroleum systems in the Western Canada Sedimentary Basin and the Central Graben area of the North Sea

    Berbesi, L. A.; di Primio, R.; Anka, Z.; Horsfield, B.


    Around 500 to 600 Tg (1 Tg = 1012 g) of methane enter the atmosphere every year, mainly as product of microbial processes and combustion of fossil fuels and burning biomass. The importance of another source, the geologic emissions of methane, is up to now only loosely constrained. In this study, we addressed the potential methane emissions during the geological evolution of the Western Canada sedimentary basin (WCSB), which holds the largest oil sand accumulations in the world, and the Central Graben area of the North Sea. In the case of the WCSB, thermogenic gas generation and leakage at the sediment surface were addressed through 3D petroleum systems modeling. In this basin, the accumulated oil experienced intense biodegradation that resulted in large masses of biogenic methane. We quantified this latter mass though a two-step mass balance approach. Firstly, we estimated the rate of petroleum degradation and the magnitude of petroleum loss. After this, we calculated the mass of biogenic methane generated using a model that assumes hexadecane (C16H34) as representative of the saturated compounds (Zengler et al., 1999). Our 3D model suggests that 90000-150000 Tg of dry gas (mostly methane) could have leaked during the interval from 80 Ma to 60 Ma. Therefore, uniform leakage rates would have been in the order of 10-3-10-2 Tg yr-1. Biogenic methane generation could have taken place at rates of 10-4 to 10-2 Tg yr-1. However, the effective mass of thermogenic and biogenic methane reaching the atmosphere might have been up to 90% lower than calculated here due to methanotrophic consumption in soils (Etiope and Klusman, 2002). We addressed the thermogenic gas generation and leakage in the Central Graben through two different methods. The first is based on a previous 3D petroleum system modeling of the region (Neumann, 2006). The second consisted of calculating the mass of generated petroleum based on source rock extension and properties (Schmoker, 1994), and then

  14. 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

    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

  15. 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

    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.

  16. Quantifying the contribution of Long-Range Transport to PM, NOx, and SO2 loadings at a suburban site in the North-Western Indo Gangetic Basin

    Pawar, Harshita; Sachan, Himanshu; Garg, Saryu; Arya, Ruhani; Singh, Nitin Kumar; Sinha, Baerbel; Sinha, Vinayak


    We investigate the climatology of air masses arriving at the IISER Mohali Atmospheric Chemistry facility (30.67°N, 76.73°E; 310 m amsl) through 3-day backtrajectories arriving at 20 m above ground level for the period August 2011-November 2012. IISER Mohali is a suburban site in the North-Western Indo Gangetic Basin. The trajectories are computed in ensemble mode twice daily with an arrival time of 2:30 pm local time (daytime) and 4:30 am local time (nighttime) using the HYSPLIT 4 model with the National Oceanic and Atmospheric Administration's GDAS file as meterological input data. Due to the close proximity of the site to the Himalayan mountain range the trajectory output is found to be very sensitive to the models input data. IISER Air Quality station is located in the IGB at an altitude of 310 m amsl approximately 20 km south west of the Shivalik hills, but the model terrain height for the site in the ensemble run output varies between 200 m amsl and 3500 m amsl for the GDAS dataset and 200 m amsl to 5000 m amsl for the reanalysis dataset. We conclude that the GDAS dataset performs better than than reanalysis dataset for our site and selected only those trajectories from the trajectory ensemble for cluster analysis, for which the terrain height in the model output was 400 m amsl for Shimla (a site located at an altitude of 1000 m amsl in the mountains 60 km north east of Mohali). We subjected the trajectories to hierarchical, and non-hierarchical (K-means) clustering and found that the air mass transport to our station can be characterised by 10 distinct airflow patterns; 3 of which occur only during the monsoon season. For pre-monsoon season (March-June), post-monsoon season (Sept-Nov) and winter season (Dec-Feb), air mass transport to our site is predominantly from the west. Direct transport of north westerly air masses to our site is subdivided into three clusters (slow, medium and rapid) while other clusters are attributed to south westerly air currents

  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

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


    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. 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

    Pigott, John D.; Abouelresh, Mohamed O.


    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

  19. Mesozoic basins and associated palaeogeographic evolution in North China

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


    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

  20. Evidence for Badenian local sea level changes in the proximal area of the North Croatian Basin

    Bakrač, Koraljka; Hajek-Tadesse, Valentina; MIKNIĆ, Mirjana; Grizelj, Anita; Hećimović, Ivan; Kovačić, Marijan


    Quantitative analysis of palynomorphs, foraminifera and ostracods enabled the recognition of biotic events and the reconstruction of environmental change in the Badenian sediments from the Vrhovčak section of Mt. Samoborsko gorje (NW Croatia). During the Middle Miocene the investigated area of Mt. Samoborska gora was located at the south-western margin of the North Croatian Basin, which represents the south-western edge of the Pannonian Basin System and the Central Paratethys Basin. This marg...

  1. Detailed cross sections of the Eocene Green River Formation along the north and east margins of the Piceance Basin, western Colorado, using measured sections and drill hole information

    Johnson, Ronald C.


    This report presents two detailed cross sections of the Eocene Green River Formation in the Piceance Basin, northwestern Colorado, constructed from eight detailed measured sections, fourteen core holes, and two rotary holes. The Eocene Green River Formation in the Piceance Basin contains the world’s largest known oil shale deposit with more than 1.5 billion barrels of oil in place. It was deposited in Lake Uinta, a long-lived saline lake that once covered much of the Piceance Basin and the Uinta Basin to the west. The cross sections extend across the northern and eastern margins of the Piceance Basin and are intended to aid in correlating between surface sections and the subsurface in the basin.

  2. Westward shift of western North Pacific tropical cyclogenesis

    Wu, Liguang; Wang, Chao; Wang, Bin


    Tropical cyclones (TCs) in the western North Pacific or typhoons account for one third of all TCs in the world and the change of the mean TC genesis location can affect billions of people in Pacific islands and Asian countries. The annual mean TC genesis longitude is generally controlled by the east-west shift of the tropical upper tropospheric trough (TUTT). A pronounced westward shift in the TUTT is found in all of the available reanalysis data sets during 1979-2012, suppressing TC genesis in the eastern portion (east of 145°E) of the western North Pacific basin due to the enhanced vertical wind shear associated with the TUTT shift. As a result, the annual mean TC genesis longitude has significantly shifted westward since 1979. The westward shifting trends in the TUTT and TC genesis are associated with the enhanced tropical tropospheric warming, which is consistent with the response of the tropospheric temperature to global warming.

  3. Extreme winds in the Western North Pacific

    Ott, Søren


    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...

  4. 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

    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

  5. Dependence between Ventilation and Climate as recorded with Biomarkers over the last 420,000 years in the Guianas Region (North-western Amazon Basin)

    Rama, O.; Lopez-Otalvaro, G.; Martrat, B.; Flores, J.; Sierro, F. J.; Grimalt, J. O.


    There is growing evidence that the majority of the Amazon rainforest survived the climatic threshold of the last ice age. This information is crucial given that this region could be currently near its critical resiliency tipping point; thus, minor climate warming, widespread reductions in precipitation and lengthening of the dry season may be sufficient to gradually contribute to the forest dieback and biodiversity loss [Cowling et al., 2004; Lenton et al., 2008; Maslin, 2004]. To contribute to this knowledge, palaeoclimatic oscillations have been identified in this study by using fossil organic compounds synthesized by marine and terrestrial flora and later accumulated on sediment strata (MD03-2616, 7N, 53W, -1233 meters below sea-level) from the Guianas region, closely linked to the Amazon Basin. Different indicators have been considered to continuously reconstruct the climate over the past 420,000 years at centennial scale: average annual sea surface temperatures (SST, Uk’37), productivity of the coccolithophora flora (alken-2-ones), continental vegetation variability (long chain n-alkanes) and changes in oxygenation of the deep-sea floor (ratio between n-alkan-1-ols and n-alkanes). At present, the Guianas region is largely influenced by migration of the intertropical convergence zone (ITCZ), related temperature and wind patterns, together with changes in hydrological conditions, atmospheric and oceanic fronts. Annual SST is 27.7C; two rain seasons and two dry seasons occur. At the core location, surface waters present complex seasonal configuration, while oxygen-enriched and low-salinity Antarctic Intermediate waters (AAIW) flow northward from -700 to -1500 meters depth; the Upper North Atlantic Deep waters circulate southward at greater depths [World Meteo. Org.; Masson & Delecluse, 2001; Arz et al., 2001]. This study reveals that completely different hydrological conditions and much colder climate occurred in the past, e.g. a harsh drop in SST of up to 24C

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

    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...

  7. Oceanography, bathymetry and syndepositional tectonics of a Precambrian intracratonic basin: integrating sediments, storms, earthquakes and tsunamis in the Belt Supergroup (Helena Formation, ca. 1.45 Ga), western North America

    Pratt, Brian R.


    The carbonate-dominated Helena Formation of the Mesoproterozoic Belt Supergroup of western North America provides an instructive example of how a range of regional depositional and environmental characteristics of an ancient sea can be deduced on the basis of micron- to metre-scale features. Particularly revealing is the window opened by the presence of abundant molar-tooth structure onto the paleoceanography, paleobathymetry, paleoclimate and tectonic regime of this intracratonic Precambrian basin. The facies hosting molar-tooth structure is composed dominantly of lime mud with substantial subangular quartz and feldspar silt and clay derived from the western and southwestern side of the basin. These are low-energy tempestites deposited on a remarkably flat sea bottom at the limit of storm-wave base, at about 50 m. Sporadic domical, stromatolite patch reefs confirm that the sea bottom was normally within the photic zone. The ubiquity of molar-tooth structure suggests frequent, near-field seismic activity during subsidence, which generated ground motion sufficient to liquefy granular lime mud and terrigenous silt. Sporadic tsunamis from major submarine faults far to the west pounded the shallow-water platform to the east. Tsunami off-surge swept ooids and rounded, coarse-grained, feldspathic quartz sand westward into deeper water, and created strongly erosive currents that left gutter casts composed of lags of preferentially cemented molar-tooth structure in otherwise relatively low-energy facies. Mineralogical and geochemical evidence, confirms that the Belt basin was marine. Organic matter was essentially fully oxidized in the water column. Original high-Mg composition and cementation of lime mud in molar-tooth structure indicate that calcite precipitated above the thermocline in supersaturated seawater under tropical conditions. Scattered bimineralic ooids in allochthonous grainstones indicate that shoals on the platform to the east were intermittently above a

  8. Browning boreal forests of western North America

    Verbyla, David


    , 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

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

    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

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

    Meredith, Karina, E-mail: [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)


    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

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

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


    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

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

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


    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

  13. Structural evolution and strike-slip tectonics off north-western Sumatra

    Berglar, Kai; Gaedicke, Christoph; Franke, Dieter; Ladage, Stefan; Klingelhoefer, Frauke; Djajadihardja, Yusuf S.


    Based on new multi-channel seismic data, swath bathymetry, and sediment echosounder data we present a model for the interaction between strike-slip faulting and forearc basin evolution off north-western Sumatra between 2 degrees N and 7 degrees N. We examined seismic sequences and sea floor morphology of the Simeulue- and Aceh forearc basins and the adjacent outer arc high. We found that strike-slip faulting has controlled the forearc basin evolution since the Late Miocene. The Mentawai Fault...

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

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


    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. Migration of western mackerel to the North Sea 1973 - 1988

    Iversen, Svein A.; Skagen, Dankert W.


    The latest years, it is evident that most of the mackerel present in the North Sea belongs to the Western stock, since the yearly catches by far exceed the presumed size of the North Sea stock. The Norwegian tagging data have been revised to obtain estimates of the percentage of Western mackerel in the catches in the North Sea. By combining these data with the distribution of catches, a reasonable estimate of the migration of the Western mackerel to the North Sea may be o...

  16. The Late Quaternary biogeographic histories of some Great Basin mammals (western USA)

    Grayson, Donald K.


    The Great Basin of arid western North America provides one of the most detailed late Pleistocene and Holocene mammal records available for any part of the world, though the record is by far strongest for small mammals. Of the 35 genera of now-extinct North American Pleistocene mammals, 19 are known to have occurred in the Great Basin, a list that is likely to be complete or nearly so. Of these 19, seven can be shown to have survived beyond 12,000 radiocarbon years ago, a proportion similar to that for North America as a whole. Horses, camels, mammoth, and helmeted musk-oxen appear to have been the most abundant of these genera. Pygmy rabbits ( Brachylagus idahoensis), yellow-bellied marmots ( Marmota flaviventris), and bushy-tailed woodrats ( Neotoma cinerea) declined in abundance at the end of the Pleistocene, at about the same time as populations south of their current arid western distributional boundary were extirpated. Subsequent declines occurred during the hot/dry middle Holocene. Pygmy rabbits also declined as modern pinyon-juniper woodlands developed across the Great Basin. The Snake Range of eastern Nevada has seen the late Pleistocene or Holocene extinction of both northern pocket gophers ( Thomomys talpoides) and pikas ( Ochotona princeps). Coupled with the rarity of yellow-bellied marmots here, these histories make the Snake Range a biogeographic oddity. These and other Great Basin mammal histories provide significant insights into the possible responses of Great Basin small mammals to global warming.

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

    A. A. Tahir; Chevallier, Pierre; Arnaud, Yves; Ashraf, M.; Bhatti, M. T.


    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 spatiotemporal change and the hydrological response of these sub-basins i...

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

    ZHANG Zhongyi; WU Ganguo; GUO Jinghui; ZHANG Da


    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

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


    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. Novel fen ecosystems in western North Carolina

    Wilcox, J. D.


    Western North Carolina is mountainous, and groundwater flows from hillslope recharge zones to valley stream and spring discharge zones. Depending on surface topography and geologic conditions, the water table may approach or intersect the ground surface to form seepage wetlands, or fens. Fen ecosystems can be very sensitive to changes in land use, groundwater pumping, and upslope development. This presentation will focus on two sites where historical land use and human activity played important roles in creating or preserving fen ecosystems. Both sites now support—and are being managed to protect—federally endangered flora and fauna. The first site is home to Sarracenia oreophilia, an endangered pitcher plant that thrives on saturated soils with low nutrient content. The site's early history includes tree clearing, drain tile installation, and cattle grazing, while more recent management activities have included drain tile excavation, manual invasive removal, and prescribed burns. A 15-year water-level record indicates seasonal artesian conditions wet a 3m clay unit (K=2E-5 cm/sec) beneath the site, which is able to retain moisture during drier periods. Shorter "clay wetting periods" during drought years (1999-2000; 2007-2008) correspond to reduced clump counts in pitcher-plant surveys. The second site is a former aggregate quarry that now supports over 60 bog turtles (Clemmys muhlenbergii). The biggest threat to this site is encroachment of non-native and invasive multiflora rose (Rosa multiflora) and other large woody species. Management activities include manual removal and prescribed goat herbivory. Current efforts to characterize the springs, water-table, and surface-water flows will be used to detect changes in the future to the hydrologic regime in the fen.

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

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


    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.

  2. Repeated glacial lake outburst flood threatening the oldest Buddhist monastery in north-western Nepal

    J. Kropáček; N. Neckel; Tyrna, B.; Holzer, N.; A. Hovden; Gourmelen, N.; Schneider, C.; M. Buchroithner; V. Hochschild


    Since 2004, Halji village, home of the oldest Buddhist Monastery in north-western Nepal, has suffered from recurrent glacial lake outburst floods (GLOFs). A sudden englacial drainage of a supraglacial lake, located at a distance of 6.5 km from the village, was identified as the source of the flood. The topography of the lake basin was mapped by combining differential Global Positioning System (DGPS) measurements with a structure-from-motion (SFM) approach using terrestrial photographs. From t...

  3. Repeated glacial lake outburst flood threatening the oldest Buddhist monastery in north-western Nepal

    J. Kropáček; N. Neckel; Tyrna, B.; Holzer, N.; A. Hovden; Gourmelen, N.; Schneider, C.; M. Buchroithner; V. Hochschild


    Since 2004, Halji village, home of the oldest Buddhist Monastery in north-western Nepal, has suffered from recurrent glacial lake outburst floods (GLOFs). A sudden englacial drainage of a supraglacial lake, located at a distance of 6.5 km from the village, was identified as the source of the flood. The topography of the lake basin was mapped by combining differential Global Positioning System (DGPS) measurements with a structure-from-motion (SFM) approach using terrestrial p...

  4. Extreme winds in the Western North Pacific

    Ott, S.


    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

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

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


    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...

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

    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


    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...

  7. The Salar de Atacama Basin: a Subsiding Block within the Western Edge of the Altiplano-Puna Plateau

    Klaus-J. Reutter; Reynaldo Charrier; Hans-J. Götze; B. Schurr; Peter Wigger; Ekkehard Scheuber; Peter Giese; Claus-Dieter Reuther; Sabine Schmidt; Andreas Rietbrock; Guillermo Chong; Arturo Belmonte-Pool


    The internally drained Salar de Atacama (SdA) Basin, located in the proximal fore-arc between the present magmatic arc (Western Cordillera) to the east and the North Chilean Precordillera (Cordillera de Domeyko) to the west, represents a prominent morphological anomaly in the Central Andean Plateau. The basin is a post-Incaic feature that developed contemporaneously with the initial plateau uplift. Before 38 Ma, the magmatic arc was positioned in the present-day Precordillera; as a result, th...

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

    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...

  9. 137Cs inventory in semi-isolated basins of the western South Pacific

    Yamada, M.; Wang, Z.


    The main introduction routes of 137Cs into the Pacific Ocean are worldwide global fallout from atmospheric nuclear weapons testing and close-in fallout from U. S. tests conducted on the Bikini and Enewetak Atolls. The objectives of this study are to measure the 137Cs activities in water columns of the western South Pacific Ocean and to discuss the processes controlling the 137Cs inventory. The 137Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea Basins of the western South Pacific Ocean. The 137Cs activities in surface waters ranged from 1.7 Bq m- 3 in the Tasman Sea Basin to 2.3 Bq m-3 in the East Caroline Basin. The latitudinal 137Cs distributions in surface waters showed the opposite trend to the expected deposition density from global fallout. The distribution profiles of 137Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. The total 137Cs inventories in the western South Pacific Ocean ranged from 850 Bq m-2 in the Coral Sea Basin to 1270 Bq m-2 in the South Fiji Basin. Higher 137Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137Cs inventories were 1.9 - 4.5 times higher than that of the expected deposition density of atmospheric global fallout at the same latitude. The possible sources of excess 137Cs inventories in the western South Pacific Ocean might be attributable to both the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137Cs from the northern stratosphere to the southern one and its subsequent deposition, and water- bearing transport of 137Cs from the North Pacific Ocean to the South Pacific.

  10. 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

    Xiaowei Feng


    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.

  11. Regional heat flow patterns in the Western Canadian Sedimentary Basin

    Majorowicz, J. A.; Jessop, A. M.


    The regional geothermal pattern of the Western Canadian Sedimentary Basin has been studied using available temperature data from wells. Average heat conductivity for various geological formations has been estimated on the basis of net rock studies by Canadian Stratigraphie Services. These data and observations of temperature made in "shut-in holes" in some of the oil pools have been used in heat flow estimations by the Bullard method. The geothermal gradient and heat flow within the basin are exceptionally high in comparison with the other world wide Precambrian platform areas. Especially high geothermal gradient areas are found in the northwestern part of the Prairies Basin in Alberta and British Columbia and most of southeastern and southwestern Saskatchewan. Areas of low gradient are found mainly in the Disturbed Belt of the Foothills, southern and southeastern Alberta, and the Peace River area in British Columbia. Neither the analysis of regional heat conductivity distribution nor the heat generation distribution of the basement rock of the Prairies Basin evaluated on the basis of U, Th and K data after Burwash (1979), explain the observed heat flow patterns of the Prairies Basin. Comparison of heat flow patterns with some of the hydrogeological phenomena suggests the significant influence of fluid flow in the basin formations on geothermal features. Low geothermal gradient areas coincide with water recharge areas and high hydraulic head distribution regions. The phenomenon of upward water movement in the deep strata and downward flow through much of the Cenozoic and Mesozoic strata seems to control the regional heat flow distribution in the basin. The analyses of coal metamorphism in the upper and middle Mesozoic formations of the Foothills Belt and in the central Prairies Basin suggest that the pre-Laramide paleogeothermal heat flow distribution was different from the present one. It is very probable that the Foothills Belt area was characterized by a higher

  12. Age and Thickness of the Lithosphere within the Western and Eastern Basins of the Black Sea according to Geophysical Data



    The ages of the western and eastern basins of the Black Sea have been estimated on the basis of heat-flow data. The obtained ages (70-60 Ma) are in good accord with the time of basins' origin as determined from seismic and magnetic data. During this time, the Black Sea opened as a back-arc basin to the north of the Pontide magmatic arc. The arc prehistory of the Pontides is confirmed by the existence of relict mantle seismicity, which is most active in the eastern Pontides. Nearly synchr...

  13. Effects of the bow on social organization in Western North America.

    Bettinger, Robert L


    The bow more than doubled, likely tripled, the success of individuals bent on killing animal or human targets (Box ). The advent of this revolutionary technology generated different responses in western North America depending on subsistence and sociopolitical organization at the time of its arrival, roughly 2300 - 1300 B.P. Its effect was substantial in California and the Great Basin, particularly on group size, which in many places diminished as a consequence of the bow's reliability. The counter-intuitive result was to increase within group-relatedness enough to encourage intensification of plant resources, previously considered too costly. The bow rose to greatest direct economic importance with the arrival of the horse, and was put to most effective use by former Great Basin groups who maintained the family band system that had developed around intensive Great Basin plant procurement, adapting the same organization to a lifestyle centered on the equestrian pursuit of buffalo and warfare. PMID:23776048

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

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


    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.

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


    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.

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

    Kare Liimatainen


    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.


    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...

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

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


    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...

  19. Childhood urolithiasis in North-Western Libya

    M Ben Halim


    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.

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

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


    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.

  1. Double-saloon-door tectonics in the North Fiji Basin

    Martin, A. K.


    Fiji Platform rotated counter clockwise from at least 10.2 Ma until 1.56 Ma, while Vanuatu Arc rotated clockwise from 12/10 Ma until the present. A revised model incorporating these opposite rotations explains the distribution of magnetic anomalies in the North Fiji Basin (NFB). The conjugate margin of southwest Fiji Platform is southeast Vanuatu Arc. Previous models which associate NW-oriented anomalies off southwest Fiji with similarly oriented anomalies northeast of Vanuatu Arc are therefore wrong. Secondly, these models propose a NW-oriented spreading ridge extending to 19°S, 177.5°E, almost 500 km southeast of the mapped extension of rifted island-arc crust on Vanuatu Arc. This creates an unacceptable overlap with Fiji Platform in pre-rift reconstructions. Thirdly, anomalies off SW Fiji which are NW-oriented in their present-day position were oriented NNE during initial breakup. Rather than aligning with NW-oriented anomalies in the western NFB, they are matched by NNE-oriented anomalies off SE Vanuatu Arc. With further rotation, these conjugate anomaly sets form a fan shape in the southern NFB. Fourthly, previous models which recognise a triple junction only from 3 Ma do not explain early WNW-ESE separation of Vanuatu Arc and Fiji Platform required by well-documented opposite rotations. NFB characteristics which match the double-saloon-door tectonic model include opposite rotations of island arc terranes, backarc seafloor spreading which is both arc-parallel and arc-perpendicular, and rifts propagating north, south, northeast and northwest. Features which do not match the double-saloon-door model include the North Fiji Fracture Zone and the West Fiji spreading centre. Both initiated post-1.5 Ma, when Fiji Platform stopped rotating, and only one terrane, Vanuatu Arc, continued to rotate. The NFB developed via double saloon door tectonics from 12/10 Ma until 1.5 Ma, whereas post-1.5 Ma opening constitutes single saloon door rotation.

  2. Fallout 137Cs in soils from North Western Libya

    Fallout levels of 137Cs in surface soil from North Western Libya have been measured using gamma-ray spectrometry. The activity concentrations of 137Cs in soil ranged from 975 to 1720 mBq x kg-1. The areal activity concentrations ranged from 1300 to 2250 mBq x m-2, and were highly correlated with annual precipitation. The effective dose from external exposure to 137Cs is found to be 3 nSv x y-1. (author)

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

    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

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

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


    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

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


    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.

  6. Rapid Middle Eocene temperature change in western North America

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


    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.

  7. Evidence for a broadly distributed Samoan-plume signature in the northern Lau and North Fiji Basins

    Price, Allison A.; Jackson, Matthew G.; Blichert-Toft, Janne; Hall, Paul S.; Sinton, John M.; Kurz, Mark D.; Blusztajn, Jerzy


    enrichment of lavas in the northern Lau Basin may reflect the influx of Samoan-plume mantle into the region. We report major and trace element abundances and He-Sr-Nd-Hf-Pb-isotopic measurements for 23 submarine volcanic glasses covering 10 locations in the northern Lau and North Fiji Basins, and for three samples from Wallis Island, which lies between Samoa and the Lau Basin. These data extend the western limit of geochemical observations in the Basins and improve the resolution of North-South variations in isotopic ratios. The Samoan hot spot track runs along the length of the northern trace of the Lau and North Fiji Basins. We find evidence for a Samoan-plume component in lavas as far West as South Pandora Ridge (SPR), North Fiji Basin. Isotopic signatures in SPR samples are similar to those found in Samoan Upolu shield lavas, but show a slight shift toward MORB-like compositions. We explain the origin of the enriched signatures by a model in which Samoan-plume material and ambient depleted mantle undergo decompression melting during upwelling after transiting from beneath the thick Pacific lithosphere to beneath the thin lithosphere in the northern Lau and North Fiji Basins. Other lavas found in the region with highly depleted isotopic signatures may represent isolated pockets of depleted mantle in the basins that evaded this enrichment process. We further find that mixing between the two components in our model, a variably degassed high-3He/4He Samoan component and depleted MORB, can explain the diversity among geochemical data from the northern Lau Basin.

  8. North American Natural Gas Outlook: Basin-on-basin competition

    Long-term trends and their impacts on the Canadian and American natural gas industry were examined, together with an assessment of the expected evolution of the natural gas markets in North America from 1995 to the year 2010. A strong growth of the natural gas markets in the U.S. and Canada was projected for the period. Demand in the two countries is expected to rise by about a third as a result of general economic growth, competitive gas prices, and efficiency and environmental advantages of gas relative to other fuels. In the U.S., much of this growth is related in some way to electricity: increased use of gas to fuel power generation facilities, a rise in the use of gas for industrial cogeneration and the displacement of electricity by gas in commercial cooling markets. In Canada however, increases in industrial gas demand, including the petrochemical sector, are expected to lead the growth in gas consumption. Canadian gas exports to the U.S. are projected to increase steadily over the period to reach 3.7 Tcf by 2010. While Alberta continues to account for over 80% of Canadian gas production, British Columbia experiences the strongest rate of production growth. In the U.S., the Gulf Coast area continues to be the dominant supply region, accounting for almost 50% of the production over the period. One of the greatest uncertainties over the period results from the deregulation of electricity markets in both the U.S. and Canada. Two other uncertainties that were identified were natural gas supply costs and the incremental tolling of pipeline expansions. 10 figs., 30 tabs., 29 refs

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

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


    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

  10. Structure and dynamics of basin forested wetlands in North America

    Freshwater basin wetlands are found in depressions of various depths, generally in areas where precipitation exceeds evapotranspiration or where the depression intersects the water table creating groundwater seeps or springs. Forested basins are those that contain woody vegetation with the potential for reaching tree stature; they do not include woody shrub wetlands. In North America these areas are mainly in the central and eastern region. Pertinent information and reviews on the distribution, floristic composition, structure and dynamics of basin forested wetlands are summarized. The major emphasis is on freshwater wetlands, but data for saltwater wetlands mainly from Florida and tropical America are included. The external factors affecting basin wetlands or the important components of a wetlands energy signature are described as well as the distribution and floristic composition of representative basin wetlands. Sections on structural characteristics, organic matter dynamics, and nutrient cycling comprise the bulk of quantitative information. The effects of disturbances, both natural and human induced, with varying degrees of impact depending upon the intensity and on the part of the ecosystem to which the stressor is applied are evaluated. Examples of stressors in basin wetlands include water impoundment, water diversion, thermal stress from hot water, sedimentation, addition of toxic substances, addition of wastewater, oil spills, and harvesting. 86 refs., 5 figs., 11 tabs

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

    McQuarrie, N.; Oskin, M.


    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, 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

  12. Organic-Carbon Burial and Oxygen Depletion Along the Margin of Western North America During the Past 60,000 Years: Teleconnections With Greenland Ice and the Cariaco Basin

    Dean, W. E.


    During Oxygen Isotope Stage 3 (OIS3; 60-24 cal ka),), the Bolling/Allerod warm interval (B/A; 15-13 cal ka), and the Holocene, bottom-water oxygen levels were much lower, and organic carbon (Corg) burial was much higher on all margins of the Californias (Alta and Baja) than during the last glacial interval (LGI; 24-15 cal ka) and the Younger Dryas cold interval (YD; 13-11.6 cal ka). Burial of Corg during the LGI-B/A-Holocene transition in the Cariaco Basin on the margin of northern Venezuela is remarkably similar to that on the California margin. Correlation between Dansgaard-Oeschger (D-O) cycles in Greenland ice with gray-scale measurements in varved sediments in the Cariaco Basin, and cycles of Corg burial on the Baja California margin are well established. Synchronous climate-driven changes as recorded in the sediments on the margins of the Californias, sediments from the Cariaco Basin, and in the GISP-2 Greenland ice core support the hypothesis that changes in atmospheric dynamics played a major role in abrupt climate change during the last 60 ky.




    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.

  14. Isotopes in Western North American snowpack 1993 - 2013

    Anderson, L.; Berkelhammer, M. B.; VanSistine, P.


    The interpretation of oxygen isotope-based climate proxies in the western North America, including those from lake sediment calcite, tree cellulose, leaf waxes, and speleothems, each depend on assumptions about the site-specific and regional patterns of the isotopic composition of seasonal precipitation. Here we explore isotopic ratios in the integrated Rocky Mountain snowpack (IRMS) since 1993 for >45 high-elevation locations per year between northern Montana and northern New Mexico. The isotopic network comprises the most extensive spatial and temporal effort to document snowpack isotopic values to be conducted beyond Polar Regions. The dataset provides new insight into the processes that influence the isotopic composition of Western North American winter precipitation. Preliminary assessments indicate a number of spatial features that are similar to those observed in existing isotopic networks from North America but with additional spatial and temporal detail over this topographically complex region. Lower isotopic ratios generally occur with higher latitude, a reflection of condensation at cooler temperatures associated with more common Arctic air mass incursions, which bring isotopically depleted vapor. Higher elevation sites also generally have lower isotopes ratios, but this is most likely as a consequence of orographic rainout. East-west isotopic gradients occur as a consequence of preferential rainout as air masses pass from west to east over the spine of the cordillera and when southern tracking lows generate east to west upslope flow. Previous studies have also indicated that isotopes in precipitation track interannual shifts in atmospheric regimes that lead to changes in jet stream strength and position and the frequency that Arctic, sub-tropical or Pacific air masses reach the Rockies. We hypothesize that these changes also yield distinct impacts on the isotopic ratio of the snowpack and use the unique spatial and temporal density of the IRMS dataset

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

    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


    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.

  16. 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)

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


    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...

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

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


    -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.

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

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


    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. PMID:25461078

  19. New evidence for the Storegga tsunami event in lake basins systems: western Norway

    Waldmann, N.; Vasskog, K.; Nesje, A.; Chapron, E.; Ariztegui, D.; Bondevik, S.


    Between 8180 and 8070 years ago, one of the largest known submarine slides occurred off the coast of mid-Norway. This event displaced about 3500 km3 of sediment, affected an area of 95,000 km2 and triggered a large tsunami that inundated coastal areas around the North Atlantic and the North Sea. In this contribution, we present first geological evidence from a high resolution geophysical survey and shallow sediment coring for the presence of a large tsunamite related to the Storegga event, in shallow lacustrine basins of Western Norway. A unique Rapidly Deposited Layer (RDL) discovered in the sedimentary infill of the lakes Nerfloen and Oppstrynsvatnet (29 m a.s.l.) is interpreted as a deposit from this tsunami. Two radiocarbon dates from within the deposit itself yield a combined age estimate of 8180-8030 cal a BP (2σ) for the RDL, which is in agreement with robust age-depth modelling of the overlying sediments and strongly supporting the correlation with the Storegga event. In the outer lake basins, where both high-resolution seismic profiles and sediment cores are available, the up to 3.5 m thick RDL covers an area of ~1.1 km2 and features an estimated sediment volume of ~1.2x106 m3. More tentatively we suggest that a ~5x106 m3 semi-transparent seismic unit in the main Oppstrynsvatnet basin could also be connected to the tsunami. Tsunami deposits of this magnitude have not been documented previously in Norwegian lakes, suggesting that the physiographic setting of the study area may have significantly amplified the tsunami wave.

  20. Western Gas Sands Project. Quarterly Basin Activities Report

    Atkinson, C H


    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)

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

    Olusegun A Babaniyi


    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.

  2. 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



    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.

  3. 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

    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

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

    Jesse Lee Morris


    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. 

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

    Sigloch, K.; Mihalynuk, M. G.


    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

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

    Dybkjær, Karen; Piasecki, Stefan


    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...

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

    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.

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

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


    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...

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

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


    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.

  10. Palaeotemperature conditions for the southwest of Western Australia from the stable isotopic composition of deep, confined groundwater within the Perth Basin

    Two major confined aquifers occur within the upper 3000 m of the sedimentary sequence forming the Perth Basin located in the south-west coastal margin of Western Australia. The aquifers comprise multi-layered sequences of interbedded sandstones, shales and siltstones and are an important groundwater resource for metropolitan Perth. Within the context of research into groundwater resource evaluation of the aquifers, undertaken by the Geological Survey of Western Australia [1], 14C, δ2H and δ18O data on the deep groundwater were collected. Samples were obtained from nine east-west transects across the coastal plain, four transects in the Northern Perth Basin and five in the Southern Perth Basin. The most northerly transect in the Northern Perth basin is 70 km north of Perth while the most southerly is 50 km south of Perth. The most northerly transect on the Southern Perth Basin is near Bunbury and the most southerly is at Karridale, giving a total north to south range for both basins of 300 km. The purpose of this paper is to investigate palaeoclimatic conditions based on isotopic data within the groundwater archive of the Perth Basin

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

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


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

    Vidal, Maria del Pilar Clemente


    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...

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

    Underdown, R; Redfern, J


    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...

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

    Clemmensen, Anne; Thomsen, Erik


    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...

  15. Cottonwood Tree Rings and Climate in Western North America

    Friedman, J. M.; Edmondson, J.; Griffin, E. R.; Meko, D. M.; Merigliano, M. F.; Scott, J. A.; Scott, M. L.; Touchan, R.


    In dry landscapes of interior western USA, cottonwood (Populus spp.) seedling establishment often occurs only close to river channels after floods. Where winter is sufficiently cold, cottonwoods also have distinct annual rings and can live up to 370 years, allowing us to reconstruct the long-term history of river flows and channel locations. We have analyzed the annual rate of cottonwood establishment along streams in Montana, Wyoming, Colorado, North Dakota and Idaho. Because the trees germinate next to the river, establishment rates are strongly correlated with the rate of channel migration driven by floods. Along large rivers dominated by snowmelt from the mountains, interannual variation in peak flows and cottonwood establishment is small, and century-scale variation driven by climate change is apparent. The upper Snake, Yellowstone and Green rivers all show a strong decrease in cottonwood establishment beginning in the late 1800s and continuing to the present, indicating a decrease in peak flows prior to flow regulation by large dams. This is consistent with published tree-ring studies of montane conifers showing decreases in snowpack at the same time scale. In contrast, beginning in the late 1800s cottonwood ring widths along the Little Missouri River, North Dakota show an increase in annual growth that continues into the present. Because annual growth is strongly correlated with April-July flows (r=0.69) the ring-width data suggest an increase in April-July flows at the same time tree establishment dates suggest a decrease in peak flows. These results may be reconciled by the hypothesis that increases in low temperatures have decreased snowpack while lengthening the growing season.

  16. Orbital control of the western North Pacific summer monsoon

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


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


    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.

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

    C. Eva


    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. The role of strain partitioning on intermontane basin inception and isolation, External Western Gibraltar Arc

    Jiménez-Bonilla, A.; Expósito, I.; Balanyá, J. C.; Díaz-Azpiroz, M.; Barcos, L.


    The intermontane Ronda Basin, currently located in the Western Betics External Zones, started as an embayment of the Betic foreland basin during the Tortonian. We have characterized a post-Serravallian, basin-related deformation event that overprinted the former fold-and-thrust belt. Updated structural and kinematic maps allow us to identify NW-SE basinward-dipping normal faults at the southwestern and northeastern boundaries of the basin and NE-SW shortening structures (large-scale folds and reverse faults) affecting both the outcropping basement and partially the basin infill. In order to test the possible tectonic activity of these structures during the last 5 Ma, exhaustive geomorphologic analyses in the Ronda Basin area have been done. This included the qualitative study of relief and drainage network, together with the characterization of quantitative indices (SLk, Smf, Vf and HI). These results obtained from this analysis are coherent with structural data and suggest that the identified post-Serravallian structures were active up to at least 5 Ma. We also conclude that the Ronda Basin was generated by along strike segmentation of the relief in the Western Betics induced by NE-SW (arc-parallel) stretching accompanied with NW-SE shortening. In the NW basin boundary, the strain was partitioned into ENE-WSW dextral strike-slip faults and NE-SW shortening structures, which gave rise to a Messinian transpressive structural high that disconnected the former Ronda Basin from its parental foreland basin.

  20. North Atlantic deep water in the south-western Indian Ocean

    van Aken, Hendrik M.; Ridderinkhof, Herman; de Ruijter, Wilhelmus P. M.


    The circulation of deep water in the south-western Indian Ocean has been studied from hydrographic observations and current measurements, obtained during the Dutch-South African Agulhas Current Sources Experiment programme, and from similar public data from the World Ocean Circulation Experiment. The three major water masses involved are the saline North Atlantic deep water (NADW), its derivative in the Antarctic circumpolar current, lower circumpolar deep water (LCDW), and the aged variety of deep water, North Indian deep water (NIDW). Although bound by the shallow topography near Madagascar, about 2×10 6 m 3/s from the upper half of the NADW core appears to flow across the sill in the Mozambique Channel into the Somali Basin, while the remaining NADW flows east at about 45°S and is transformed to LCDW by lateral and diapycnal mixing. East of Madagascar the deep circulation is dominated by the southward flow of NIDW. Northward inflow of LCDW into the Indian Ocean therefore can take place only in the eastern half of the Indian Ocean, along the Southeast Indian Ridge and the Ninetyeast Ridge.

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

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


    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.

  2. Repeated glacial lake outburst flood threatening the oldest Buddhist monastery in north-western Nepal

    Kropáček, J.; Neckel, N.; Tyrna, B.; Holzer, N.; Hovden, A.; Gourmelen, N.; Schneider, C.; Buchroithner, M.; Hochschild, V.


    Since 2004, Halji village, home of the oldest Buddhist Monastery in north-western Nepal, has suffered from recurrent glacial lake outburst floods (GLOFs). A sudden englacial drainage of a supraglacial lake, located at a distance of 6.5 km from the village, was identified as the source of the flood. The topography of the lake basin was mapped by combining differential Global Positioning System (DGPS) measurements with a structure-from-motion (SFM) approach using terrestrial photographs. From this model the maximum filling capacity of the lake has been estimated as 1.06 ×106 m3 with a maximum discharge of 77.8 m3 s-1, calculated using the empiric Clague-Mathews formula. A simulation of the flooded area employing a raster-based hydraulic model considering six scenarios of discharge volume and surface roughness did not result in a flooding of the village. However, both the village and the monastery are threatened by undercutting of the river bank formed by unconsolidated sediments, as it already happened in 2011. Further, the comparison of the GLOF occurrences with temperature and precipitation from the High Asia Reanalysis (HAR) data set for the period 2001-2011 suggests that the GLOF is climate-driven rather than generated by an extreme precipitation event. The calculation of geodetic mass balance and the analysis of satellite images showed a rapid thinning and retreat of Halji Glacier which will eventually lead to a decline of the lake basin. As the basin will persist for at least several years, effective mitigation measures should be considered. A further reinforcement of the gabion walls was suggested as an artificial lake drainage is not feasible given the difficult accessibility of the glacier.

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

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


    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.

  4. Status of woodland caribou in western north America

    E. Janet Edmonds


    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. The alkenone temperature signal in western North Atlantic surface waters

    Conte, M. H.; Weber, J. C.; King, L. L.; Wakeham, S. G.


    Haptophyte algae-derived long-chain C 37-C 39 alkenones and alkyl alkenoates were analyzed in euphotic zone particulate matter collected over a 7 yr period at the Oceanic Flux Program/Bermuda Atlantic Time Series (OFP/BATS) site in the western Sargasso Sea. Surface water temperatures at the site range annually from 19 to 29°C. Alkenone concentrations ranged from 100 ng L -1 following the passage of storms. Highest seasonal concentrations occurred during the late winter and spring. Under stratified conditions, alkenone concentrations in the surface mixed layer (0-20 m) were generally 2 to 4 times higher than in the deep fluorescent maximum (75-110 m), consistent with Emiliania huxleyi concentration profiles (Haidar and Thierstein, 2001) and indicated that alkenone production primarily occurs within the upper euphotic zone in this region. Alkenone compound distributions and the temperature calibrations of C 37 and C 38 methyl and ethyl alkenone unsaturation (U 37K', U 38MeK, and U 38EtK, respectively) were remarkably similar to that observed in an E. huxleyi strain previously isolated from the same area (Conte et al., 1998), providing strong evidence that E. huxleyi is the predominant alkenone synthesizer and that characteristics exhibited by randomly isolated clones in culture are, in many cases, consistent with those of populations in the region of origin. The Bermuda calibration of U 37K' vs. water temperature (U 37K' = -1.9835 + 0.2004T - 0.0034T 2, r 2 = 0.95, n = 91) is nonlinear and falls along the same trendline as euphotic zone particulates from warm (> 15°C) waters of the eastern North Atlantic (Conte and Eglinton, 1993) and Mediterranean (Ternois et al., 1997). The combined North Atlantic temperature calibration (U 37K' = - 1.1365 + 0.1257T - 0.0018T 2, r 2 = 0.963, n = 134) differs significantly from published coretop sediment calibrations (Rosell-Melé et al., 1995; Müller et al., 1998) based on sea surface temperature maps (Levitus and Boyer, 1994

  6. Effects of tropical North Atlantic SST on tropical cyclone genesis in the western North Pacific

    Yu, Jinhua; Li, Tim; Tan, Zhemin; Zhu, Zhiwei


    The tropical cyclone genesis number (TCGN) in July-October (JASO) over the western North Pacific (WNP) exhibits a robust interannual variation. It shows a longitudinally tri-pole pattern with a high in the eastern WNP and South China Sea (SCS) and a low in the western WNP, which explain 42.2 and 23.4 % of total TCGN variance in the eastern WNP and SCS, respectively. The high-low-high pattern is similar to that derived from a TC genesis potential index (GPI). To understand the cause of the longitudinal distribution of the dominant interannual mode, we examine the contributions of environmental parameters associated with GPI. It is found that relative humidity and relative vorticity are important factors responsible for TC variability in the SCS, while vertical shear and relative vorticity are crucial in determining TC activity in eastern WNP. A simultaneous correlation analysis shows that the WNP TCGN in JASO is significantly negatively correlated (with a correlation coefficient of -0.5) with sea surface temperature anomalies (SSTA) in the tropical North Atlantic (TNA). The longitudinal distribution of TC genesis frequency regressed onto TNA SSTA resembles that regressed upon the WNP TCGN series. The spatial patterns of regressed environmental variables onto the SSTA over the TNA also resemble those onto TCGN in the WNP, that is, an increase of relative humidity in the SCS and a weakening of vertical shear in the eastern WNP are all associated with cold SSTA in the TNA. Further analyses show that the cold SSTA in the TNA induce a negative heating in situ. In response to this negative heating, a low (upper)-level anomalous aniti-cyclonic (cyclonic) flows appear over the subtropical North Atlantic and eastern North Pacific, and to east of the cold SSTA, anomalous low-level westerlies appear in the tropical Indian Ocean. Given pronounced mean westerlies in northern Indian Ocean in boreal summer, the anomalous westerly flows increase local surface wind speed and surface

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

    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

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

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


    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

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

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


    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

  10. 90-Sr in Milk in the North-Western Croatia

    The program of radioactivity measurements and monitoring of the human environment in Croatia, carried out by the Radiation Protection Unit of the Institute for Medical Research and Occupational Heath in Zagreb, involve also investigations of radiostrontium in milk and milk products. Milk is a very important foodstuff and a critical food in respect to the presence and persistence of nuclides in the body. Because of its high calcium content, milk is used as a sensitive indicator for the presence of fission products in foods and in the environment. It is also an important route of entry of radiostrontium from fallout to man. Radiostrontium, a highly toxic radionuclide, is similar to calcium in its chemical behaviour, including its deposition in human bone. The paper describes investigation of 90Sr activity in milk collected over the period of six year at two locations in the north-western part of the Republic of Croatia. 90Sr was determined by extraction with tributyl phosphate. 90Sr was measured on basis of radioactive balance with its decay product 90Y, counted by low background level anti-coincidence shielded GM counter. In the Republic of Croatia, milk consumption of approximately 100 L per year/person can potentially lead to the accumulation of significant radiation dose. The doses received from milk consumption are small, but owing to the long retention time of 90Sr in bone which can be the basis for its potential hazard, 90Sr level require continuous control and monitoring. Special emphasis should be given to children as the most vulnerable part of population. (author)

  11. Urinary stone disease in Kano, North Western Nigeria

    S A Aji


    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.

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

    Garfin, Gregg; Orr, Barron


    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

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

    Ryde, A.


    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.

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

    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

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

    J. Vincent


    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

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

    M. Pandolfi


    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

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

    M. Pandolfi


    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

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

    M. S. Kooij


    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. Flash heat simulation events in the north Mediterranean basin

    Mazon, Jordi; Pino, David


    According to the definition of flash heat event proposed by Mazon et al. in the European Meteorology Meeting (2011 and 2012) from the studied case produced in the Northeast of the Iberian peninsula on 27th August 20120, some other flash heat events have been detected by automatic weather stations around the in the Mediterranean basin (South Italy, Crete island, South Greece and the northeast of the Iberian peninsula). Flash heat event covers those events in which a large increase of temperature last a spatial and temporal scale between heat wave (defined by the WMO as a phenomenon in which the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5°C, with respect to the 1961-1990 period) and heat burst (defined by the AMS as a rare atmospheric event characterized by gusty winds and a rapid increase in temperature and decrease in humidity that can last some minutes). Thus flash heat event may be considered as a rapid modification of the temperature that last several hours, lower than 48 hours, but usually less than 24 hours. Two different flash heat events have been simulated with the WRF mesoscale model in the Mediterranean basin. The results show that two different mechanisms are the main causes of these flash heat events. The first one occurred on 23rd March 2008 in Crete Island due to a strong Foehn effect caused by a strong south and southeast wind, in which the maximum temperature increased during some hours on the night at 32°C. The second one occurred on 1st August 2012 in the northeast of the Iberian Peninsula, caused by a rapid displacement of warm a ridge from North Africa that lasted around 24 hours.

  20. Localized accumulation and a shelf-basin gradient of particles in the Chukchi Sea and Canada Basin, western Arctic

    Yamada, Yosuke; Fukuda, Hideki; Uchimiya, Mario; Motegi, Chiaki; Nishino, Shigeto; Kikuchi, Takashi; Nagata, Toshi


    Transparent exopolymer particles (TEP), particulate organic carbon (POC), and particles (size range: 5.2-119 μm) as determined by laser in situ scattering and transmissometry (LISST) were measured in the water column from the Chukchi Sea to the Canada Basin in the western Arctic Ocean, during the late summer of 2012. In general, the percentages of TEP-carbon to POC were high (the mean values for the shelf and slope-basin regions were 135.4 ± 58.0% (± standard deviation, n = 36) and 187.6 ± 73.3% (n = 58), respectively), relative to the corresponding values reported for other oceanic regions, suggesting that TEP play an important role in regulating particle dynamics. A hotspot (extremely high concentration) of particles, accompanied by high prokaryote abundance and production, was observed near the seafloor (depth 50 m) of the shelf region. Localized accumulation of particles was also found in the thin layer near the pycnocline (depth 10-30 m) and on the slope. Over a broader spatial scale, particle concentration gradients were identified from the shelf to the basin in the upper water column (TEP are produced in the shelf region and are potentially delivered to the slope-basin region along the pycnocline, which might support productivity and material cycles in the nutrient-depleted basin region of the western Arctic Ocean.

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

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


    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

  2. A multi-scale analysis of tropical cyclogenesis within the critical layer of tropical easterly waves in the Atlantic and western North Pacific sectors

    Lussier, Louis L.


    A newly proposed tropical cyclogenesis sequence that describes the transition of a tropical wave's critical layer to a tropical cyclone is used to examine two formation cases in the western North Pacific basin. Typhoon Nuri (2008), formed from a precursor easterly wave during the Tropical Cyclone Structure 2008 field experiment, and Typhoon Man-yi (2007), formed within an equatorial Rossby wave as it interacted with a monsoon trough. In each case, i) the critical layer of the parent wave pr...

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

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


    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)

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

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


    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...

  5. Fukushima-derived radiocesium in western North Pacific sediment traps

    M. C. Honda


    Full Text Available At two stations in the western North Pacific, K2 in the subarctic gyre and S1 in the subtropical gyre, time-series sediment traps were collecting sinking particles when the Fukushima Daiichi Nuclear Power Plant (FNPP1 accident occurred on 11 March 2011. Radiocesium (134Cs and 137Cs derived from FNPP1 accident was detected in sinking particles collected at 500 m by late March 2011 and at 4810 m by early April 2011 at both stations. The sinking velocity of 134Cs and 137Cs was estimated to be 8 to 36 m day−1 between the surface and 500 m and > 180 m day−1 between 500 m and 4810 m. 137Cs specific activity varied from 0.14 to 0.25 Bq g−1 dry weight. These values are higher than those of surface seawater, suspended particles, and zooplankton collected in April 2011. Although the radiocesium may have been adsorbed onto or incorporated into clay minerals, correlations between 134Cs and lithogenic material were not always significant; therefore, the form of the cesium associated with the sinking particles is still an open question. The total 137Cs flux by late June at K2 and by late July at S1 was 0.5 to 1.7 Bq m−2 at both depths. Compared with 137Cs input to both stations by April 2011, estimated from the surface 137Cs activity and mixed layer depth and by assuming that the observed 137Cs flux was constant throughout the year, the estimated removal rate of 137Cs from the upper layer (residence time in the upper layer was 0.3 to 1.5% (68 to 312 yr. The estimated removal rates and residence times are comparable to previously reported values.

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

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


    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

  7. Estimating the Length of the North Atlantic Basin Hurricane Season

    Wilson, Robert M.


    For the interval 1945-2011, the length of the hurricane season in the North Atlantic basin averages about 130 +/- 42 days (the +/-1 standard deviation interval), having a range of 47 to 235 days. Runs-testing reveals that the annual length of season varies nonrandomly at the 5% level of significance. In particular, its trend, as described using 10-yr moving averages, generally has been upward since about 1979, increasing from about 113 to 157 days (in 2003). Based on annual values, one finds a highly statistically important inverse correlation at the 0.1% level of significance between the length of season and the occurrence of the first storm day of the season. For the 2012 hurricane season, based on the reported first storm day of May 19, 2012 (i.e., DOY = 140), the inferred preferential regression predicts that the length of the current season likely will be about 173 +/- 23 days, suggesting that it will end about November 8 +/- 23 days, with only about a 5% chance that it will end either before about September 23, 2012 or after about December 24, 2012.

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

    Titeca, Kristof


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

    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...

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

    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...

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

    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...

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

    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...

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

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


    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.

  14. PCBs and OCPs in marine species from the Belgian North Sea and the Western Scheldt Estuary

    Voorspoels, S.; Covaci, A.; Maervoet, J.; Schepens, P. [Antwerp Univ., Wilrijk (Belgium). Toxicological Centre


    The use and/or production of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), such as 2,2-bis-(4-chlorophenyl)-1,1,1-trichloroethane (DDT), hexachlorobenzene (HCB) and lindane ({gamma}-HCH) have been banned in most developed countries since the 1970's. Despite this measure, these compounds are among the most prevalent environmental pollutants and they can be found in various environmental compartments, both biotic and abiotic. Their widespread presence is due to their extremely persistant and lipophilic nature, resulting in enrichment throughout the food chain. Prolonged exposure to these pollutants can interfere with normal physiology and biochemistry3, resulting in adverse effects in various organisms, including starfish, shrimp, crabs, and fish4. Because humans readily consume seafood, such as shrimp, crab and various fish species, these organisms are of great scientific value to estimate the possible exposure to PCBs and OCPs through marine food sources. The area studied in this investigation covered both commercial fishing grounds (Belgian North Sea - BNS) and a recreational fishing area (Western Scheldt Estuary - SE). The drainage basin of the SE covers a very densely populated and highly industrialised region, causing a high level of pollution in the SE. In this work, PCBs and OCPs were determined in benthic invertebrates and different fish species from both BNS and SE in order to evaluate trends in levels, congener distribution, and geographical variation.

  15. The thermal history of the western lower Saxony Basin, Germany

    Adriasola Muñoz, Yvonne


    Since about 30 years the maturity and geophysical anomalies within the Lower Saxony Basin (LSB) were interpreted as a result of a deep lying igneous intrusion called “Bramsche Massif”. Based on the lignite/subbituminous coal stage of Upper Campanian rocks overlying the Lower Cretaceous units, a late Early Cretaceous or early Late Cretaceous age was concluded for the time of intrusion. Vitrinite reflectances for the central and southern part of the LSB confirm a low reflectance increase with d...

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

    G. Chouliaras


    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.

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

    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

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

    Wang, B.; Zhou, X.


    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.

  19. Franciscan olistoliths in Upper Cretaceous conglomerate deposits, Western Transverse Ranges, California: Implications for basin morphology and tectonic history

    Reed, W.E.; Campbell, M.D. (Univ. of California, Los Angeles, CA (United States). Dept. of Earth and Space Sciences)


    Compositional analyses reveal that Upper Cretaceous sediments exposed in the Western Transverse Ranges of CA were deposited in submarine fan systems in a forearc basin. Point count data suggest a magmatic arc/recycled orogen as the dominant provenance for these sediments. Paleocurrent measurements from conglomerates in these sediments yield a northerly transport direction. Removal of ca. 90[degree] of clockwise rotation and 70 km of right-lateral slip restore this section to a position west of the San Diego area. The forearc basin would have had a N-S orientation, with the bulk of sediments supplied by the Peninsular Ranges to the east. Evidence of the erosion of the accretionary wedge is provided by the presence of large, internally stratified olistoliths of Franciscan material interbedded with and surrounded by upper Cretaceous conglomerate. Petrographic, quantitative SEM, and microprobe analyses indicate the presence of diagnostic Franciscan mineralogy, including glaucophane, riebeckite, lawsonite, and serpentine. Olistoclasts of chert, jadeitic graywacke, serpentine, and blueschist are found intermixed with the conglomerates in close association with the olistoliths. This association provides strong field evidence that recirculation of melange material within the subduction zone was active and well-established by late Cretaceous time. Inferences regarding the forearc system morphology can be drawn from these observations. The occurrence of coarse, easterly-derived conglomerates surrounded by large, stratified, but sheared, westerly-derived Franciscan debris, suggests a narrow, relatively steep-sided basin. Paleocurrent measurements gave no indication of axial transport within the basin. This morphology suggests that, in late Cretaceous time, the forearc basin was youthful, with a narrow arc-trench gap. Thus, relative convergence rates between the North American and Pacific plates were possibly slower than Tertiary convergence rates.

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

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


    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

  1. Geology and natural gas occurrence, western Williston Basin

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


    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.

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

    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...

  3. Long-term geochemical connections between the Samoan hotspot and the northern Lau and North Fiji Basins

    Price, A. A.; Jackson, M. G.; Blichert-Toft, J.; Hall, P. S.; Sinton, J. M.; Kurz, M. D.; Blusztajn, J.


    The Lau and North Fiji Basins provide a unique environment for the study of upper mantle flow around a subducting slab due to the juxtaposition of the Tonga Trench and the Samoan hotspot (Hart et al., 2004). Both geochemical and geophysical data suggest that material from the Samoan hotspot is leaking southward into the adjacent Lau Basin, but the direction and rate of mantle flow are difficult to constrain.Spatial variations in the isotope geochemistry of igneous rocks from the Lau Basin can provide a useful window on flow in the upper mantle. For example, some lavas from the Samoan hotspot exhibit high 3He/4He, and the observation of elevated 3He/4He at Rochambeau Bank in the nearby northern Lau Basin has been interpreted as the result of a 'finger-like' intrusion of Samoan-plume mantle into the region. However, high 3He/4He is rare even in Samoan lavas, so other geochemical signatures including radiogenic 87Sr/86Sr and Pb-isotopic compositions unique to the Samoan hotspot are useful for characterizing the spatial distribution of the Samoan component within the northern Lau and North Fiji Basins. We present analyses of a combination of geochemical tracers (He-Hf-Nd-Sr-Pb isotopes, major, and trace elements) measured on glasses from the northern Lau Basin and the North Fiji Basin. The samples have 3He/4He ratios that vary between 6 and 10.5 times atmospheric. The samples also show arange in isotopic values from extremely depleted (87Sr/86Sr=0.702892, 143Nd/144Nd=0.513218 and 176Hf/177Hf=0.283510 on a ridge 100km North of Fiji) to moderately enriched (87Sr/86Sr=0.703598, 143Nd/144Nd=0.512884 and 176Hf/177Hf=0.283082 in lavas fromPandora Ridge). Notably, moderately enriched isotopic compositions in Pandora Ridge lavas plot near Samoa's Upolu Island in isotope space, but are slightly shifted isotopically towards a depleted MORB mantle component. The new data suggestthat the western extent of the Samoan plume's influence in the region extends into both the

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

    Niu, Y.


    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

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

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


    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.

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

    Khukhuudei, Ulambadrakh; Otgonbayar, Orolzodmaa


    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.

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

    Zhou Shuqing; Huang Haiping; Liu Yuming


    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

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

    Simon Weides


    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.

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

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


    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

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

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


    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

  11. Mesoscale cyclogenesis over the western North Pacific Ocean during TPARC

    Davis, Christopher A.; Sarah C. Jones; Anwender, Doris; Badey, Janina; Scheck, Leonhard


    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 c...

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

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


    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...

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

    Ayse Ozlem Goral


    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

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

    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.


    A. V. Marinin


    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.  

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

    Methner, Katharina; Mulch, Andreas; Chamberlain, Page


    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

  17. 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)

    Akkouche, M


    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

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

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


    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

  19. A Geodetic Strain Rate Model for the Pacific-North American Plate Boundary, western United States

    Kreemer, C.; Hammond, W. C.; Blewitt, G.; Holland, A. A.; Bennett, R. A.


    We present a model of crustal strain rates derived from GPS measurements of horizontal station velocities in the Pacific-North American plate boundary in the western United States. The model reflects a best estimate of present-day deformation from the San Andreas fault system in the west to the Basin and Range province in the east. Of the total 2,846 GPS velocities used in the model, 1,197 are derived by ourselves, and 1,649 are taken from (mostly) published results. The velocities derived by ourselves (the "UNR solution") are estimated from GPS position time-series of continuous and semi-continuous stations for which data are publicly available. We estimated ITRF2005 positions from 2002-2011.5 using JPL's GIPSY-OASIS II software with ambiguity resolution applied using our custom Ambizap software. Only stations with time-series that span at least 2.25 years are considered. We removed from the time-series continental-scale common-mode errors using a spatially-varying filtering technique. Velocity uncertainties (typically 0.1-0.3 mm/yr) assume that the time-series contain flicker plus white noise. We used a subset of stations on the stable parts of the Pacific and North American plates to estimate the Pacific-North American pole of rotation. This pole is applied as a boundary condition to the model and the North American - ITRF2005 pole is used to rotate our velocities into a North America fixed reference frame. We do not include parts of the time-series that show curvature due to post-seismic deformation after major earthquakes and we also exclude stations whose time-series display a significant unexplained non-linearity or that are near volcanic centers. Transient effects longer than the observation period (i.e., slow viscoelastic relaxation) are left in the data. We added to the UNR solution velocities from 12 other studies. The velocities are transformed onto the UNR solution's reference frame by estimating and applying a translation and rotation that minimizes

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

    Wilson, Robert M.


    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.

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

    Harrison, Brent


    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...

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

    Hasson, Shabeh ul; Lucarini, Valerio


    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...

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

    Walker, Tony Robert


    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. Chronostratigraphy and tectonic deformation of the North Ecuadorian-South Colombian offshore Manglares forearc basin

    Marcaillou, B.; Collot, Jean-Yves


    Forearc basins in convergent margins contain a nearly continuous record of sedimentation and deformation. Their chronostratigraphy reflects the manner in which the basin accommodates loads and vertical and horizontal motion caused by eustasy, tectonics and sedimentation during plate convergence. Along the North Ecuador and South Colombia (NESC) Margin (1 degrees-3.5 degrees N), thick Cenozoic sedimentary sequences accumulated over blocks of oceanic basement that accreted between the Late Cret...

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

    Messori, Gabriele; Caballero, Rodrigo; Gaetani, Marco


    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.

  6. Lead isotopes in the western North Atlantic: Transient tracers of pollutant lead inputs

    In the early 1980s, Patterson and colleagues demonstrated that most lead in oceanic surface waters had an anthropogenic origin. Their discovery occurred during the phasing out of leaded gasoline in North America initiated in the previous decade. The corresponding decrease in anthropogenic lead emissions, verified by Pb/210Pb ratios, accounted for the systematic decline in lead concentrations in surface waters of the western Sargasso Sea. Subsequent changes in anthropogenic lead inputs to the western Sargasso Sea surface waters have been documented by measurements of lead concentrations, isotopic compositions (206Pb/207Pb, 208Pb/206Pb), and Pb/210Pb ratios in precipitation and seawater for the period of 1981 to 1994. These data indicate the easterly trade winds are now the primary source of atmospheric lead in Bermuda, and they confirm that the decline of lead concentrations in the North Atlantic is associated with the phasing out of leaded gasoline in North America and western Europe over the past decade. Moreover, temporal variations in the relative contribution of industrial lead inputs from the two sides of the North Atlantic over that period can be quantified based on differences in their isotopic composition. The transient character of those isotopic signatures also allows calculations of pollutant lead penetration rates into the mixed layer and upper thermocline of the western Sargasso Sea

  7. Natural Radioactivity Levels in Environmental Samples in North Western Desert of Egypt

    Soil and sediment samples were collected from North western desert of Egypt. Gamma spectroscopy was used to determine the concentration of naturally occurring radionuclides 238 U,232 Th and 40 K. The hazard index due to these radionuclides has been calculated. The measurement results obtained from this study indicate that the region has background radioactivity levels within natural limits

  8. Minor and trace metals levels in human milk in north western cities of Libya

    Levels of twelve minor and trace metals were determined by using (AAS, ES and ICP/MS) in breast milk obtained from 60 women living in north western cities of Libya. Samples were collected at one week up to two years after delivery. Women with age>21 years old to an age of <43 years old were investigated. (Author)

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

    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…

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

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


    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

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

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


    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 u...

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

    Wilson, Robert M.


    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.

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

    PANDEY; Dhirendra; Kumar; FüRSICH; Franz; Theodor


    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

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

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


    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

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

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


    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

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

    WANG HuiJun; FAN Ke


    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.

  17. 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

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


    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.

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

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


    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.

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

    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)


    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.

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

    Christopher A. Davis


    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.

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

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


    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.

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


    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).


    To assess the impact of entrainment of larval fishes at steam generating electrical power plants, samples were collected in Lake Erie. In 1975, 1976 and 1977 the Western Basin was sampled and in 1978 the sampling was concentrated in the Central Basin. The 1975, 1976 sampling perm...

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

    Abdunaser, K. M.


    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

  5. The Mediterranean basin

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


    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...

  6. Cenozoic coupled basin-mountain and prospecting direction for sandstone-type uranium deposits in western Yunnan

    The initial forming time of Cenozoic basins in western Yunnan is at 14 Ma or so, it was coupling in the later period tectonic activity time of Lushui-Ruili arc dextral strike-slip fault belt in the eastern fringe and Nabang dextral strike-slip fault belt in the western fringe of Tengchong microplate. The evolution of Cenozoic basins is divided into two stages of sedimentary basin and reformed basin, the former was coupling in the strike-slip tectonic activity of orogen, and formed strike-slip basins, the latter was closely related with the uplift of the whole basins, and formed residual basins. It is considered that there exists two sorts of Cenozoic basins, and they are different in sedimentary evolution, volcanic activity and geographic sight etc., the metallogenic conditions of sandstone-type uranium deposits are also different. The most favourable basins for prospecting sandstone-type uranium deposits are those basins that keeps on uplifting in reformed basin stages, exists volcanic activity and deep incised low mountain-hill-river valley terraces in northern Tengchong area. (authors)

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

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


    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.

  8. Monitoring interannual variability of vegetation in the western Liaohe River Basin, Northeast China

    Huang, Fang; Wang, Ping; Qin, Yujun; Li, Yanqing


    Because vegetation affect several processes including water balance, absorption and reemission of solar radiation, latent and sensible heat fluxes, and carbon cycle, the variations in the composition and distribution of vegetation represents one of the most main source of systematic change on local, regional, or global scale. To monitor and better assess natural or man-made change in vegetation of the earth is desirable for modeling and predicting interactions between land surface and atmosphere. The temporal evolution of decadal NDVI composition is regarded as an effective time window able to show the natural seasonal variations. This paper investigates vegetation change between 1998 and 2006 in the west Liao River watershed, North China, which is the east fringe of agro-pasture transitional zone in northern China and highly sensitive to global change. Time series of SPOT-VEGETATION Normalized Difference Vegetation Index (NDVI) data are used to detect the vegetation cover change during last 9 years. Results show that the yearly maximum value composite mean NDVI over the study area increased slightly from 0.277 in 1998 to 0.287 in 2006, which indicated the increasing trend of vegetation activity. The annual average NDVI value in whole area was steady. Very slight improved and slight improved area reached 113442.32 km2 and 27987.34 km2, taking up 67.81% and 16.73% of the whole study area respectively. The degraded regions occupied about 15.16%. During 1998-2006, the landscape evolution in the western Liaohe River Basin was characterized by two opposite processes, namely vegetation restoration (returning cropland for farming to grassland and close grazing) and desertification (especially land salinization). The increasing amplitude is larger than the decreasing amplitude on the whole. There was obvious decrease of monthly MNDVI in spring months, while increasing tendency of monthly MNDVI in summer and autumn was found. Results will help to provide valuable

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

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


    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.

  10. Beyond Positive Sciences : an Anthropological Approach to Market Analysis in North-Western Ghana

    Dessein, JPG.


    Full Text Available Western science has often been thought of as an universally applicable, dominant and neutral knowledge system. Recently this view has been challenged by various scientists, who try to revalue the subjugated knowledge systems of local people by appreciating its characteristics. But this upgrading of endogenous knowledge often is but another example of the hegemonie position of Western science : it evaluates local situations with Western criteria, neglecting the cultural paradigms of the people involved. This article is a plea for a new multidisciplinary and intercultural research approach which takes as its foundation an understanding of the local culture and paradigms on which selected topics can be analysed, rather than a traditional disciplinary approach in which, afterwards, a foreign cultural component is being inscribed. This appeal is supported by material from a local market in North-western Ghana, where the Lobi peasants sell their harvest to the Wala traders.

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

    Sappenfield, Aaron Dale


    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...

  12. A potential archive of Pleistocene uplift and erosion in the eastern Nete basin, Campine area, north-eastern Belgium

    Beerten, Koen; Leterme, Bertrand


    of ONDRAF/NIRAS. References Hijma, M.P., Cohen, K.M., Roebroeks, W., Westerhoff, W.E., Busschers, F.S., 2012. Pleistocene Rhine-Thames landscapes: geological background for hominin occupation of the southern North Sea region. Journal of Quaternary Science, 27, 17-39. Toucanne, S., Zaragosi, S., Bourillet, J.F., Gibbard, P.L., Eynaud, F., Giraudeau, J., Turon, J.L., Cremer, M., Cortijo, E., Martinez, P., Rossignol, L., 2009. A 1.2 Ma record of glaciation and fluvial discharge from the Western European Atlantic margin. Quaternary Science Reviews, 28, 2974-2981. van Balen, R.T., Houtgast, R.F., Van der Wateren, F.M., Vandenberghe, J., Bogaart, P.W., 2000. Sediment budget and tectonic evolution of the Meuse catchment in the Ardennes and the Roer Valley Rift System. Global and Planetary Change, 27, 113-129. Westaway, 2001. Flow in the lower continental crust as a mechanism for the Quaternary uplift of the Rhenish Massif, north-west Europe. In: Maddy, D., Macklin, M.G. & Woodward, J.C. (eds) River Basin Sediment Systems: Archives of Environmental Change. Balkema (Rotterdam), 87-167.

  13. Pollen analysis of coal-bearing Miocene sedimentary rocks from the Seyitomer basin (Kutahya), western Anatolia

    Yavuz-Isik, N. [Ondokuz Mayis University, Kurupelit (Turkey). Dept. of Civil Engineering


    The late Early-Middle Miocene sequences of the Seyitomer Basin (western Anatolia) were palynologically investigated. Fifty-five taxa belonging to seven gymnospermous and 48 angiospermous pollen genera were identified in the 19 productive samples. Two pollen zones were recognised based on the changing abundance of individual tree taxa. Zone 1 is characterized by predominance of Pinus and Cedrus. Zone 2 is characterized by predominance of deciduous Quercus and evergreen Quercus and a marked reduction in representation of Taxodiaceae. The differences in the pollen spectra between Zone 1 and Zone 2 may reflect the global Middle Miocene cooling. These results are largely comparable to pollen data derived from the neighbouring areas. The vegetation of the Seyitomer Basin was dominated by trees. This palynological analysis reveals the existence of a swamp-forest developed in a subtropical to warm-temperate humid climate.

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

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


    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)

  15. Research on supplying potential of uranium source from rocks in western provenance area of Hailaer basin

    Using U-Pb isotope composition evolution, this paper expounds the initial uranium content in volcanic rocks of provenance area of Xihulitu basin and in granites of provenance area of Kelulun sag, western Hailaer basin. The initial uranium content (U0) in volcanic rocks of provenance area is higher, the average initial uranium content of volcanic rocks is 10.061 x 10-6, the average uranium variation coefficient (ΔU) is -49.57%; the average initial uranium content of granites is 18.381 x 10-6, the average uranium variation coefficient (ΔU) is -80%. The results indicate that rocks in provenance area could provide the pre-enrichment of uranium in deposited sandstone. U-Ra equilibrium coefficients of rocks indicate that there is obvious U-Ra disequilibrium phenomenon in volcanic rocks, and the time when granites provided uranium source occurred 16000 a ago. (authors)

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

    Lienau, P.J.


    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.

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

    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)

  18. [Comparison of biotic index used in monitoring of 2 lotic systems in north-western Argentina].

    Salusso, María M; Moraña, Liliana B


    Two lotic bodies located in a subtropical semi-arid region in north-western Argentina were studied: the Arias-Arenales and the Rosario rivers. Both rivers are located in Salta Province, and belong to the high basin of river Juramento, connected to the river Río de la Plata and the Atlantic Ocean. The study was conducted between March 1997 and March 1998. The region is known by its sustained economic development and one of the highest population growth rates in the country (4% per year). The objective of this work was the assessment of organic pollution spatial gradients in both rivers, as a function of the hydrological regime (a long period of drought from May to October and floodings the rest of the year). Three groups of biotic indices were applied to characterize the level of organic pollution and were based on planktonic microalgae to evaluate water quality. The relative performance of these indices was then compared for use to biomonitoring programs. The diversity indices: Shannon-Weaver and Whilm-Dorris were not highly sensible to detect moderate pollution. The saprobity indices (Pantle and Buck and Diatom Assemblage Index of Watanabe et al.), were useful to detect intermediate levels of organic load, but their sensitivity dropped at high pollution levels. The second index precisely discriminated the most deteriorated part of river Rosario, with values between 0.3-0.7 (extreme poli-saprobity). Raw sewage discharges along the most polluted sector of river Arias-Arenales were assigned a value between 10 and 11 in both periods of the hydrological regime. Both saprobity indices consider the same indicator pollution value of species. The first one is based on the relative abundance of the species while the second one is calculated with the species relative frequency. The second index is better than the first one in considering non-dominant species that were constant in each particular environmental condition. The principal component analysis allowed a

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

    Gülyüz, Erhan; Özkaptan, Murat; Kaymakcı, Nuretdin


    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

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

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


    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.

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

    W. Sasaki


    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.

  2. Study on geochronology of sandstone-type uranium mineralization in western Hailaer basin

    The study on U-Pb isotopic dating of sandstone-type uranium mineralization in western Hailaer basin, namely, Xihulitu and Kelulun depressions, has been carried out. The ages of 81 ± 2 Ma, 44 ± 2 Ma, 9 ± 2 Ma, 2 ± 0 Ma for sandstone-type uranium mineralization in Xihulitu depression and 51 ± 8 Ma, 67 ± 5 Ma for sandstone-type uranium mineralization in Kelulun depression have been obtained for the first time by U-Pb isochron dating. These mineralization ages are in good accordance with the tectonic and climatic evolution histories of the study area

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


    [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...

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

    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.


    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

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

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


    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...

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

    Dukes, Jeffrey S.; Mooney, Harold A.


    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,...

  7. Cultural Transmission of Traditional Knowledge in two populations of North-western Patagonia

    Lozada Mariana; Ladio Ana H; Eyssartier Cecilia


    Abstract Background In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs. Methods Ethnobotanical fieldwork was conducted by means of semi-st...

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

    Kagabo, M.D.


    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...

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

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


    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...

  10. Assessing Crop-Livestock Interaction in Mixed Farming Systems of North Western Kenya

    Wanyama, J. M; Muyekho, F. N; Lusweti, N. F.; Lusweti, C. M.; Omamo, E; Wairimu, K. N.; Kariuki, Nelson; Komen, John


    A study was conducted in the four counties the maize- wheat-teapotato and sugarcane-based farming system in North western Kenya to explore the variability among household characteristics and farm productivity. The aim of this work was to establish homogenous groups of crop-livestock mixed farming systems of Kenya. A two step approach was adopted for the study. The first was a rapid rural appraisal followed by a formal survey aimed at establishing farm types to facilitate detailed analysis of ...

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

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


    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...

  12. Trans-Pacific Transport of Saharan Dust to Western North America: A Case Study

    Kendry, Ian G. M.; Strawbridge, Kevin B.; O'Neill, Norman; Macdonald, Anne Marie; Liu, Peter S. K.; Leaitch, W. Richard; Anlauf, Kurt G.; Jaegle, Lyatt; Fairlie, T. Duncan; Westphal, Douglas L.


    The first documented case of long range transport of Saharan dust over a pathway spanning Asia and the Pacific to Western North America is described. Crustal material generated by North African dust storms during the period 28 February - 3 March 2005 reached western Canada on 13-14 March 2005 and was observed by lidar and sunphotometer in the Vancouver region and by high altitude aerosol instrumentation at Whistler Peak. Global chemical models (GEOS-CHEM and NRL NAAPS) confirm the transport pathway and suggest source attribution was simplified in this case by the distinct, and somewhat unusual, lack of dust activity over Eurasia (Gobi and Takla Makan deserts) at this time. Over western North America, the dust layer, although subsiding close to the boundary layer, did not appear to contribute to boundary layer particulate matter concentrations. Furthermore, sunphotometer observations (and associated inversion products) suggest that the dust layer had only subtle optical impact (Aerosol Optical Thickness (Tau(sub a500)) and Angstrom exponent (Alpha(sub 440-870) were 0.1 and 1.2 respectively) and was dominated by fine particulate matter (modes in aerodynamic diameter at 0.3 and 2.5microns). High Altitude observations at Whistler BC, confirm the crustal origin of the layer (rich in Ca(++) ions) and the bi-modal size distribution. Although a weak event compared to the Asian Trans-Pacific dust events of 1998 and 2001, this novel case highlights the possibility that Saharan sources may contribute episodically to the aerosol burden in western North America.

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

    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


    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

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

    TAO Li; FU Xiouhua; WANG Bin


    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.

  15. Post-Glacial Development of Western North Atlantic - Labrador Sea Oceanographic Circulation

    Sheldon, Christina


    , the subpolar gyre weakened, which carried less Gulf Stream-derived water to the western North Atlantic Ocean via the West Greenland Current and the Slopewater Current, south of Newfoundland. Changes in the subpolar gyre circulation had developed to be analogous to the modern climate by approximately 2 cal kyr...... surface currents involved in the gyre are the south-flowing, cold and relatively fresh Labrador Current and the north-flowing, warm and relatively saline Gulf Stream. The oceanic front between these two major currents moves north and south, dependent on the relative strengths of the currents, impacting...... analyses, all constrained by radiocarbon dates. At the height of the Last Glacial Maximum, there was a large, confluent ice stream draining the Uummannaq fjords on central west Greenland which extended to the shelf edge. By 15,000 years BP, the ice had begun to retreat from the outer shelf, aided...

  16. Krušné hory Piedmont basins. North Bohemian Lignite (Most) Basin

    Elznic, A.; Macůrek, V.; Dašková, Jiřina; Fejfar, O.; Kvaček, Z.; Mikuláš, Radek; Pešek, J.; Sýkorová, Ivana; Teodoridis, V.

    Prague: Czech Geological Survey, 2014, s. 31-89 ISBN 978-80-7075-862-5 R&D Projects: GA ČR GA105/06/0653 Institutional support: RVO:67985891 ; RVO:67985831 Keywords : Tertiary basins * Czech Republic * Cenomanian and Tertiary lignite * geology * stratigraphy Subject RIV: DB - Geology ; Mineralogy




    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.

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

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


    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

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

    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,...

  20. Influence of palaeotopography on the distribution of coal in the Western Coalfield, Sydney basin, Australia: comparison with South African coals

    Hutton, A. C.; Feldtmann, R.


    The Western Coalfield of New South Wales, centred on the town of Lithgow, is one of several areas of the Sydney Basin (Australia) that produces Permian coals for export and for domestic: use. The lowermost seam of the Illawarra Coal Measures, the Lithgow seam, was deposited in an alluvial fan to proximal braidplain complex. The style of clastic sedimentation and coal seam development was strongly influenced by the palaeotopography, especially basement highs which represent erosional remnants of the pre-Permian erosional cycle. The influence of the palaeotopography is seen in the distribution of the basal conglomerate, the thickness of the basal Shoalhaven Group (which is thinnest on and near the basement highs), the location of the alluvial fan facies of the Illawarra Coal Measures (which are adjacent to the highs and received a large proportion of the clastic detritus from these highs) and the development of the coal seams (which are distal to the basement highs). Of great significance is the location of economic sections of the Lithgow seam with respect to palaeotopographic highs. Adjacent to the highs the Lithgow seam is either too thin or contains too many claystone bands to allow mining. Between the highs: and further to the east and north of the highs, where the precursor peats formed on the floodplain and interfan areas, the seam is of significantly better quality and has been mined.

  1. Long-period magnetotelluric survey from the black forest through the Western Alps to the Po Basin

    Complete text of publication follows. Magnetotelluric (MT) soundings in the period range of 8s to 100000s were carried out along a 400-kilometre-long North-South profile from the Black Forest through the Western Alps, with focus on the Ivrea Zone, to the Po Basin. Several RAP-Stations, MT devices developed at the University of Goettingen, were mounted to collect data between October 2008 and May 2009. The survey aims to investigate the evolution of the conductivity structures in the lower crust and mantle along the profile. MT-transfer functions were calculated to investigate the interruption of the intracrustal and asthenospheric high conductivity layers under the European Alps. Furthermore Sq-variations were considered to find out more about the structure of the upper mantle. First results with models made by MT-forward modelling are presented and additionally a comparison with seismic studies in the target areas and particularly about the Alpine Crustal root in the Po Plain is provided. First results indicate a lithospheric thickening under the collision zones.

  2. A cultural task analysis of implicit independence: comparing North America, Western Europe, and East Asia.

    Kitayama, Shinobu; Park, Hyekyung; Sevincer, A Timur; Karasawa, Mayumi; Uskul, Ayse K


    Informed by a new theoretical framework that assigns a key role to cultural tasks (culturally prescribed means to achieve cultural mandates such as independence and interdependence) in mediating the mutual influences between culture and psychological processes, the authors predicted and found that North Americans are more likely than Western Europeans (British and Germans) to (a) exhibit focused (vs. holistic) attention, (b) experience emotions associated with independence (vs. interdependence), (c) associate happiness with personal achievement (vs. communal harmony), and (d) show an inflated symbolic self. In no cases were the 2 Western European groups significantly different from one another. All Western groups showed (e) an equally strong dispositional bias in attribution. Across all of the implicit indicators of independence, Japanese were substantially less independent (or more interdependent) than the three Western groups. An explicit self-belief measure of independence and interdependence showed an anomalous pattern. These data were interpreted to suggest that the contemporary American ethos has a significant root in both Western cultural heritage and a history of voluntary settlement. Further analysis offered unique support for the cultural task analysis. PMID:19634973

  3. Rhinocerotidae from the Upper Miocene deposits of the Western Pannonian Basin (Hungary): implications for migration routes and biogeography

    Pandolfi, Luca; Gasparik, Mihály; Magyar, Imre


    Although the rhinoceros remains have high biochronological significance, they are poorly known or scarcely documented in the uppermost Miocene deposits of Europe. Several specimens collected from the Upper Miocene (around 7.0 Ma, Turolian) deposits of Kávás (Pannonian Basin, Western Hungary), previously determined as Rhinoceros sp., are revised and described in this paper. The postcranial remains of these specimens belong to "Dihoplus" megarhinus (de Christol) on the basis of the morphological and morphometric characters of humerus, radii, metacarpal and metatarsal elements. An overview of rhinoceros remains from several uppermost Miocene localities and the revision of the rhinoceros material from the Pannonian Basin suggest that "D." megarhinus spread during the latest Miocene from the Pannonian Basin towards Italy. The occurrences of this species in Western Hungary and Italy during the latest Miocene further imply that Rhinocerotini species were biogeographically segregated between Western, Southern and Central Europe.

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

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


    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.

  5. Short-term natural gas deliverability from the Western Canada Sedimentary Basin 2000-2002

    Factors which affect natural gas supply in the short term are discussed and a forecast for deliverability to the year 2002 is provided as part of the ongoing effort by the National Energy Board to provide analyses of the major energy commodities on either an individual or integrated commodity basis. The objective of these energy market assessment reports is to advance the understanding of the short-term supply situation by reviewing recent trends in the production characteristics of the Western Canada Sedimentary Basin and to update previous reports on short-term deliverability. This report focuses on a review of producing characteristics of natural gas wells from 1990 to 1999. These producing characteristics are then combined with forecasts of drilling activity in order to generate a forecast of natural gas deliverability from 2000 to 2002. Two key trends were identified during the review process. First, recently drilled wells were found to produce at lower rates than wells drilled more than five years ago; second, production from these wells were shown to decline more quickly than production from older wells. Based on these observations, it was concluded that future wells will be generally less productive than wells which were drilled a few years ago, therefore, more wells will have to be drilled to offset production declines from existing gas wells if deliverability is to be maintained or increased. The National Energy Board expects 8,100 wells to be drilled in 2000, followed by 8,700 natural gas wells in 2001 and 8,900 in 2002. A shift in drilling activity to more prolific areas located in the western and northern parts of the Western Canada Sedimentary Basin is also expected. Based on these estimates of expected drilling activity, total deliverability is projected to increase from 465 million cubic feet per day in 1999 to 495 million cubic feet in 2002. Specialized statistics and forecast data are provided in the appendices. 3 tabs., 11 figs., 6 appendices

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

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


    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.

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

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


    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

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

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


    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

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

    Astibia, H.; Tosquella Angrill, Josep


    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...

  10. Kernel Density Estimation of Tropical Cyclone Frequencies in the North Atlantic Basin

    Timothy A. Joyner; Robert V. Rohli


    Previous research has identified specific areas of frequent tropical cyclone activity in the North Atlantic basin. This study examines long-term and decadal spatio-temporal patterns of Atlantic tropical cyclone frequencies from 1944 to 2009, and analyzes categorical and decadal centroid patterns using kernel density estimation (KDE) and centrographic statistics. Results corroborate previous research which has suggested that the Bermuda-Azores anticyclone plays an integral role in the directio...

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

    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,...

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

    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...

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



    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.

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

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


    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).

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

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


    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.

  16. 2009 Spring floods in North Dakota, western Minnesota, and northeastern South Dakota

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


    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

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

    Carlotto, Víctor


    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

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

    Martín-González, F.; Heredia, N.


    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

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

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


    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

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

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


    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...


    MA Li-ping; CHEN Lian-shou


    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.

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

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


    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

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

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


    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.

  4. 137Cs vertical distribution at the deep basins of the North and Central Aegean Sea, Greece

    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

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

    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

  6. The role of tropical Atlantic SST anomalies in modulating western North Pacific tropical cyclone genesis

    Huo, Liwei; Guo, Pinwen; Hameed, Saji N.; Jin, Dachao


    The connection between north tropical Atlantic (NTA) sea surface temperature (SST) anomalies and tropical cyclone (TC) genesis over the western North Pacific (WNP) and associated physical mechanisms are investigated in this study. We demonstrate a remarkable negative correlation of WNP TC genesis frequency with the (preceding) boreal spring NTA SST anomalies. Our analysis suggests that major factors for TC genesis including distributions of large-scale vorticity and midtropospheric humidity are rendered unfavorable by remote teleconnections while barotropic energy conversion from the large-scale flow is suppressed. As shown in recent studies, the remote teleconnection from the Atlantic is sustained and enhanced throughout the typhoon season through local air-sea interactions. These results suggest that boreal spring NTA SST anomaly could be a new predictor for the seasonal WNP TC activity.

  7. Tropical cyclone-related socio-economic losses in the western North Pacific region

    Welker, Christoph Simon; E. Faust


    The western North Pacific (WNP) is the area of the world most frequently affected by tropical cyclones (TCs). However, little is known about the socio-economic impacts of TCs in this region, probably because of the limited relevant loss data. Here, loss data from Munich RE's NatCatSERVICE database is used, a high-quality and widely consulted database of natural disasters. In the country-level loss normalisation technique we apply, the original loss data are normalised to present-day exposure ...

  8. Tropical cyclone-related socio-economic losses in the western North Pacific region

    Welker, Christoph; Faust, Eberhard


    The western North Pacific (WNP) is the area of the world most frequently affected by tropical cyclones (TCs). However, little is known about the socio-economic impacts of TCs in this region, probably because of the limited relevant loss data. Here, loss data from Munich RE’s NatCat-SERVICE database is used, a high-quality and widely consulted database of natural disasters. In the country-level loss normalisation technique we apply, the original loss data are normalised to present-day expos...

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

    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

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

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


    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.