Sample records for oasis valley region
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Delineation of the Pahute Mesa–Oasis Valley groundwater basin, Nevada
Fenelon, Joseph M.; Halford, Keith J.; Moreo, Michael T.
2016-01-22
This report delineates the Pahute Mesa–Oasis Valley (PMOV) groundwater basin, where recharge occurs, moves downgradient, and discharges to Oasis Valley, Nevada. About 5,900 acre-feet of water discharges annually from Oasis Valley, an area of springs and seeps near the town of Beatty in southern Nevada. Radionuclides in groundwater beneath Pahute Mesa, an area of historical underground nuclear testing at the Nevada National Security Site, are believed to be migrating toward Oasis Valley. Delineating the boundary of the PMOV groundwater basin is necessary to adequately assess the potential for transport of radionuclides from Pahute Mesa to Oasis Valley.The PMOV contributing area is defined based on regional water-level contours, geologic controls, and knowledge of adjacent flow systems. The viability of this area as the contributing area to Oasis Valley and the absence of significant interbasin flow between the PMOV groundwater basin and adjacent basins are shown regionally and locally. Regional constraints on the location of the contributing area boundary and on the absence of interbasin groundwater flow are shown by balancing groundwater discharges in the PMOV groundwater basin and adjacent basins against available water from precipitation. Internal consistency for the delineated contributing area is shown by matching measured water levels, groundwater discharges, and transmissivities with simulated results from a single-layer, steady-state, groundwater-flow model. An alternative basin boundary extending farther north than the final boundary was rejected based on a poor chloride mass balance and a large imbalance in the northern area between preferred and simulated recharge.
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Gravity and magnetic study of the Pahute Mesa and Oasis Valley region, Nye County, Nevada
Mankinen, Edward A.; Hildenbrand, Thomas G.; Dixon, Gary L.; McKee, Edwin H.; Fridrich, Christopher J.; Laczniak, Randell J.
1999-01-01
Regional gravity and aeromagnetic maps reveal the existence of deep basins underlying much of the southwestern Nevada volcanic field, approximately 150 km northwest of Las Vegas. These maps also indicate the presence of prominent features (geophysical lineaments) within and beneath the basin fill. Detailed gravity surveys were conducted in order to characterize the nature of the basin boundaries, delineate additional subsurface features, and evaluate their possible influence on the movement of ground-water. Geophysical modeling of gravity and aeromagnetic data indicates that many of the features may be related to processes of caldera formation. Collapse of the various calderas within the volcanic field resulted in dense basement rocks occurring at greater depths within caldera boundaries. Modeling indicates that collapse occurred along faults that are arcuate and steeply dipping. There are indications that the basement in the western Pahute Mesa - Oasis Valley region consists predominantly of granitic and/or fine-grained siliceous sedimentary rocks that may be less permeable to groundwater flow than the predominantly fractured carbonate rock basement to the east and southeast of the study area. The northeast-trending Thirsty Canyon lineament, expressed on gravity and basin thickness maps, separates dense volcanic rocks on the northwest from less dense intracaldera accumulations in the Silent Canyon and Timber Mountain caldera complexes. The source of the lineament is an approximately 2-km wide ring fracture system with step-like differential displacements, perhaps localized on a pre-existing northeast-trending Basin and Range fault. Due to vertical offsets, the Thirsty Canyon fault zone probably juxtaposes rock types of different permeability and, thus, it may act as a barrier to ground-water flow and deflect flow from Pahute Mesa along its flanks toward Oasis Valley. Within the Thirsty Canyon fault zone, highly fractured rocks may serve also as a conduit
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Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith, J. LaRue; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.
2002-01-01
Oasis Valley is an area of natural ground-water discharge within the Death Valley regional ground-water flow system of southern Nevada and adjacent California. Ground water discharging at Oasis Valley is replenished from inflow derived from an extensive recharge area that includes the northwestern part of the Nevada Test Site (NTS). Because nuclear testing has introduced radionuclides into the subsurface of the NTS, the U.S. Department of Energy currently is investigating the potential transport of these radionuclides by ground water flow. To better evaluate any potential risk associated with these test-generated contaminants, a number of studies were undertaken to accurately quantify discharge from areas downgradient in the regional ground-water flow system from the NTS. This report refines the estimate of ground-water discharge from Oasis Valley. Ground-water discharge from Oasis Valley was estimated by quantifying evapotranspiration (ET), estimating subsurface outflow, and compiling ground-water withdrawal data. ET was quantified by identifying areas of ongoing ground-water ET, delineating areas of ET defined on the basis of similarities in vegetation and soil-moisture conditions, and computing ET rates for each of the delineated areas. A classification technique using spectral-reflectance characteristics determined from satellite imagery acquired in 1992 identified eight unique areas of ground-water ET. These areas encompass about 3,426 acres of sparsely to densely vegetated grassland, shrubland, wetland, and open water. Annual ET rates in Oasis Valley were computed with energy-budget methods using micrometeorological data collected at five sites. ET rates range from 0.6 foot per year in a sparse, dry saltgrass environment to 3.1 feet per year in dense meadow vegetation. Mean annual ET from Oasis Valley is estimated to be about 7,800 acre-feet. Mean annual ground-water discharge by ET from Oasis Valley, determined by removing the annual local precipitation
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Magnetotelluric study of the Pahute Mesa and Oasis Valley regions, Nye County, Nevada
Schenkel, Clifford J.; Hildenbrand, Thomas G.; Dixon, Gary L.
1999-01-01
Magnetotelluric data delineate distinct layers and lateral variations above the pre-Tertiary basement. On Pahute Mesa, three resistivity layers associated with the volcanic rocks are defined: a moderately resistive surface layer, an underlying conductive layer, and a deep resistive layer. Considerable geologic information can be derived from the conductive layer which extents from near the water table down to a depth of approximately 2 km. The increase in conductivity is probably related to zeolite zonation observed in the volcanic rock on Pahute Mesa, which is relatively impermeable to groundwater flow unless fractured. Inferred faults within this conductive layer are modeled on several profiles crossing the Thirsty Canyon fault zone. This fault zone extends from Pahute Mesa into Oasis Valley basin. Near Colson Pond where the basement is shallow, the Thirsty Canyon fault zone is several (~2.5) kilometers wide. Due to the indicated vertical offsets associated with the Thirsty Canyon fault zone, the fault zone may act as a barrier to transverse (E-W) groundwater flow by juxtaposing rocks of different permeabilities. We propose that the Thirsty Canyon fault zone diverts water southward from Pahute Mesa to Oasis Valley. The electrically conductive nature of this fault zone indicates the presence of abundant alteration minerals or a dense network of open and interconnected fractures filled with electrically conductive groundwater. The formation of alteration minerals require the presence of water suggesting that an extensive interconnected fracture system exists or existed at one time. Thus, the fractures within the fault zone may be either a barrier or a conduit for groundwater flow, depending on the degree of alteration and the volume of open pore space. In Oasis Valley basin, a conductive surface layer, composed of alluvium and possibly altered volcanic rocks, extends to a depth of 300 to 500 m. The underlying volcanic layer, composed mostly of tuffs, fills the
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Geohydrology of Monitoring Wells Drilled in Oasis Valley near Beatty, Nye County, Nevada, 1997
Robledo, Armando R.; Ryder, Philip L.; Fenelon, Joseph M.; Paillet, Frederick L.
1999-01-01
Twelve monitoring wells were installed in 1997 at seven sites in and near Oasis Valley, Nevada. The wells, ranging in depth from 65 to 642 feet, were installed to measure water levels and to collect water-quality samples. Well-construction data and geologic and geophysical logs are presented in this report. Seven geologic units were identified and described from samples collected during the drilling: (1) Ammonia Tanks Tuff; (2) Tuff of Cutoff Road; (3) tuffs, not formally named but informally referred to in this report as the 'tuff of Oasis Valley'; (4) lavas informally named the 'rhyolitic lavas of Colson Pond'; (5) Tertiary colluvial and alluvial gravelly deposits; (6) Tertiary and Quaternary colluvium; and (7) Quaternary alluvium. Water levels in the wells were measured in October 1997 and February 1998 and ranged from about 18 to 350 feet below land surface. Transmissive zones in one of the boreholes penetrating volcanic rock were identified using flowmeter data. Zones with the highest transmissivity are at depths of about 205 feet in the 'rhyolitic lavas of Colson Pond' and 340 feet within the 'tuff of Oasis Valley.'
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Ma, Ming-guo; Wang, Xue-mei; Cheng, Guo-dong
2003-03-01
The study on the oasis corridor landsape is a new hotspot in the ecological environment research in the arid regions. In oasis, main corridor landscape types include river, ditch, shelterbelt and road. This paper introduces the basic ecological effects of the corridor landscape on the transporting mass and energy and obstructing desert landscape expansion and incursion. Using Geographic Information System (GIS), we have researched the corridor distribution and its spatial relationship with other landscape types in the Jinta Oasis. Based on the dynamically monitoring on the landscape pattern change of the Jinta Oasis during the latter 10 years by using Remote Sensing (RS) and GIS, the driving functions of the corridors on this change have been analyzed in detail. The analysis results showed that all kinds of corridors' characteristics can be quantified by the indexes such as length and width, ratio of perimeter and area, density and non-heterogeneity. The total corridor length of Jinta Oasis is 1838.5 km and its density is 2.1 km/km2. The corridor density of the irrigation land, forest and resident area is maximal, which shows that affection degree of the oasis corridors on them is the most. The improvement of the corridors quality is one of the important driving factors on the irrigation land and so on. The organic combination of the RS and GIS technologies and landscape research methods would be an effective means for the corridor landscape research on arid region oasis.
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Lin, Yong Chong; Xu, Li Shuai
2017-04-18
In order to understand the environmental influence of oasis-desert ecotone to oasis ecological system, we comparatively analyzed the grain size characteristics of various aeolian sediments, including the sediments in oasis-desert ecotone, shelterbelt and the inside oasis and in Qira River valley. The results showed that the grain size characteristics (including grain-size distribution curve, grain size parameters, and content of different size classes) of sediments in the oasis-desert ecotone were consistent along the prevailing wind direction with a grain-size range of 0.3-200 μm and modal size of 67 μm. All of the sediments were good sorting and mainly composed of suspension components and saltation components, but not denatured saltation and creeping components (>200 μm). They were typically aeolian deposits being short-range transported. The grain sizes of sediments in oasis-desert ecotone were smaller than that in the material sources of Qira River valley and desert (0.3-800 μm), but very similar to those of the modern aeolian deposits in oasis-desert ecotone, shelterbelt and the inside oasis. The denatured saltation and creep components (>200 μm) were suppressed to transport into oasis-desert ecotone because of the high vegetation cover in oasis-desert ecotone. Therefore, like the shelterbelts, the oasis-desert ecotone could also block the invasion of desert. They safeguarded the oasis ecological environment together.
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NASA Astrophysics Data System (ADS)
Abbas, Abbas M.; Ghazala, Hosni H.; Mesbah, Hany S.; Atya, Magdy A.; Radwan, Ali; Hamed, Diaa E.
2016-06-01
Bahariya Oasis is one of the lately inspected spots in Egypt and has a long historical record extending from the old kingdom till the emergence of Islam. Since June 1999, the Valley of the Golden Mummies near Bawiti (at kilometer 6 on the road leads to Farafra Oasis) became significant due to the discoveries of amazing mummies of gelded faces. The archeologists believe that the Valley has more valuable tombs that still unrevealed. Also, the possibility that the Greco-Roman Necropolis extends to areas other than Kilo-6 is sustainable. The ground penetrating radar and electrical resistivity tomography are two geophysical tools that have successful applications in archeological assessment. The two techniques were used in integration plan to assert the archeological potentiality of the studied site and to map the feasible tombs. Sum of 798 GPR profiles and 19 ERT cross sections was carried out over the study area. The results of them were analyzed to envisage these results in archeological terms.
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NASA Astrophysics Data System (ADS)
Shu, P.; Li, B.; Wang, H.; Cheng, P.; An, Z.; Zhou, W.; Zhang, D. D.
2017-12-01
Taklimakan Desert, the largest arid landform in the Eurasia, is one of the most important dust sources in the world. Growing evidences shows that millennial-scale abrupt climate changes during the last glacial period in the region. However, records on millennial-scale climate and environmental changes remain poorly understood because dating eolian, lacustrine, and fluvial sediments and establishing the reliable environmental proxies from these records are always challenging. Here, we present 32 AMS 14C dates of bulk sediments, grain size, and Rb/Sr ratio parameters from the oasis sequence and dates of bulk loess and charcoal from the upstream source regions to examine the significance of oasis sediments on millennial-scale environmental changes in the Taklimakan Desert. We found that substantial reversal of radiocarbon dates on total organic carbon (TOC) was controlled by source region organic carbon input. Loess hills, alpine meadow north of the study region provided fluvial deposits along drainage system and deflation in the river valleys further provide eolain materials. We argue that early oasis deposits experienced deflation and re-deposition less severe than the younger oasis deposits. After refining radiocarbon age-depth relationships for an age model by Bacon package, proxy records show substantial abrupt fluctuations in climate and environments during the last glacial period, among which three wet intervals, two dry periods are identified. The wetter and warmer conditions during the Holocene facilitated human to occupy the oasis.
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The oasis effect and summer temperature rise in arid regions - case study in Tarim Basin
Hao, Xingming; Li, Weihong; Deng, Haijun
2016-01-01
This study revealed the influence of the oasis effect on summer temperatures based on MODIS Land Surface Temperature (LST) and meteorological data. The results showed that the oasis effect occurs primarily in the summer. For a single oasis, the maximum oasis cold island intensity based on LST (OCILST) was 3.82 °C and the minimum value was 2.32 °C. In terms of the annual change in OCILST, the mean value of all oases ranged from 2.47 °C to 3.56 °C from 2001 to 2013. Net radiation (Rn) can be used as a key predictor of OCILST and OCItemperature (OCI based on air temperature). On this basis, we reconstructed a long time series (1961–2014) of OCItemperature and Tbase(air temperature without the disturbance of oasis effect). Our results indicated that the reason for the increase in the observed temperatures was the significant decrease in the OCItemperature over the past 50 years. In arid regions, the data recorded in weather stations not only underestimated the mean temperature of the entire study area but also overestimated the increasing trend of the temperature. These discrepancies are due to the limitations in the spatial distribution of weather stations and the disturbance caused by the oasis effect. PMID:27739500
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Geologic map of the Oasis Valley basin and vicinity, Nye County, Nevada
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fridrich, C.J.; Minor, S.A.; Ryder, P.L.
2000-01-13
This map and accompanying cross sections present an updated synthesis of the geologic framework of the Oasis Valley area, a major groundwater discharge site located about 15 km west of the Nevada Test Site. Most of the data presented in this compilation is new geologic map data, as discussed below. In addition, the cross sections incorporate new geophysical data that have become available in the last three years (Grauch and others, 1997; written comm., 1999; Hildenbrand and others, 1999; Mankinen and others, 1999). Geophysical data are used to estimate the thickness of the Tertiary volcanic and sedimentary rocks on themore » cross sections, and to identify major concealed structures. Large contiguous parts of the map area are covered either by alluvium or by volcanic units deposited after development of the major structures present at the depth of the water table and below. Hence, geophysical data provide critical constraints on our geologic interpretations. A companion paper by Fridrich and others (1999) and the above-cited reports by Hildenbrand and others (1999) and Mankinen and others (1999) provide explanations of the interpretations that are presented graphically on this map. This map covers nine 7.5-minute quadrangles in Nye County, Nevada, centered on the Thirsty Canyon SW quadrangle, and is a compilation of one published quadrangle map (O'Connor and others, 1966) and eight new quadrangle maps, two of which have been previously released (Minor and others, 1997; 1998). The cross sections that accompany this map were drawn to a depth of about 5 km below land surface at the request of hydrologists who are modeling the Death Valley groundwater system.« less
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Quinlivan, W.D.; Byers, F.M.
1977-01-01
Silica variation diagrams presented here are based on 162 chemical analyses of tuffs, lavas, and intrusives, representative of volcanic centers of the Timber Mountain-Oasis Valley caldera complex and cogenetic rocks of the Silent Canyon ca1dera. Most of the volcanic units sampled are shown on the U.S. Geological Survey geologic map of the Timber Mountain caldera area (I-891) and are described in U.S. Geological Survey Professional Paper 919. Early effusives of the complex, although slightly altered, are probably chemically, and petrographically, more like the calc-alkalic Fraction Tuff (Miocene) of the northern Nellis Air Force Base Bombing and Gunnery Range to the north, whereas effusives of later Miocene age, such as the Paintbrush and Timber Mountain Tuffs, are alkali-calcic.
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NASA Astrophysics Data System (ADS)
Smith, P. H.; tomasko, M. G.; McEwen, A.; Rice, J.
2000-07-01
The next phase of unmanned Mars missions paves the way for astronauts to land on the surface of Mars. There are lessons to be learned from the unmanned precursor missions to the Moon and the Apollo lunar surface expeditions. These unmanned missions (Ranger, Lunar Orbiter, and Surveyor) provided the following valuable information, useful from both a scientific and engineering perspective, which was required to prepare the way for the manned exploration of the lunar surface: (1) high resolution imagery instrumental to Apollo landing site selection also tremendously advanced the state of Nearside and Farside regional geology; (2) demonstrated precision landing (less than two kilometers from target) and soft landing capability; (3) established that the surface had sufficient bearing strength to support a spacecraft; and (4) examination of the chemical composition and mechanical properties of the surface. The search for extinct or extant life on Mars will follow the water. However, geomorphic studies have shown that Mars has had liquid water on its surface throughout its geologic history. A cornucopia of potential landing sites with water histories (lakes, floodplains, oceans, deltas, hydrothermal regions) presently exist. How will we narrow down site selection and increase the likelihood of finding the signs of life? One way to do this is to identify 'Martian oases.' It is known that the Martian surface is often highly fractured and some areas have karst structures that support underground caves. Much of the water that formed the channels and valley networks is thought to be frozen underground. All that is needed to create the potential for liquid water is a near surface source of heat; recent lava flows and Martian meteorites attest to the potential for volcanic activity. If we can locate even one spot where fracturing, ice, and underground heat are co-located then we have the potential for an oasis. Such a discovery could truly excite the imaginations of both the
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NASA Astrophysics Data System (ADS)
Xie, Yuchu; Gong, Jie; Sun, Peng; Gou, Xiaohua
2014-12-01
As one of the vital research highlights of global land use and cover change, oasis change and its interaction with landscape pattern have been regarded as an important content of regional environmental change research in arid areas. Jinta oasis, a typical agricultural oasis characterized by its dramatic exploitation and use of water and land resources in Hexi corridor, northwest arid region in China, was selected as a case to study the spatiotemporal oasis change and its effects on oasis landscape pattern. Based on integration of Keyhole satellite photographs, KATE-200 photographs, Landsat MSS, TM and ETM+ images, we evaluated and analyzed the status, trend and spatial pattern change of Jinta oasis and the characteristics of landscape pattern change by a set of mathematical models and combined this information with landscape metrics and community surveys. During the period of 1963a-2010a, Jinta oasis expanded gradually with an area increase of 219.15 km2, and the conversion between oasis and desert was frequent with a state of “imbalance-balance-extreme imbalance conditions”. Moreover, most of the changes took place in the ecotone between oasis and desert and the interior of oasis due to the reclamation of abandoned land, such as Yangjingziwan and Xiba townships. Furthermore, the area, size and spatial distribution of oasis were influenced by human activities and resulted in fundamental changes of oasis landscape pattern. The fractal characteristics, dispersion degree and fragmentation of Jinta oasis decreased and the oasis landscape tended to be simple and uniform. Oasis change trajectories and its landscape pattern were mainly influenced by water resource utilization, policies (especially land policies), demographic factors, technological advancements, as well as regional economic development. We found that time series analysis of multi-source remote sensing images and the application of an oasis change model provided a useful approach to monitor oasis change
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NASA Technical Reports Server (NTRS)
Adams, James H., Jr.; Barghouty, Abdulnasser F.; Binns, W. robert; Christl, Mark; Cosse, Charles B.; Guzik, T. Gregory; deNolfo, Georgia A.; Hams,Thomas; Isbert, Joachim; Israel, Martin H.;
2010-01-01
The Orbiting Astrophysical Observatory in Space (OASIS) is a mission to investigate Galactic Cosmic Rays (GCRs), a major feature of our galaxy. OASIS will use measurements of GCRs to determine the cosmic ray source, where they are accelerated, to investigate local accelerators and to learn what they can tell us about the interstellar medium and the processes that occur in it. OASIS will determine the astrophysical sources of both the material and acceleration of GCRs by measuring the abundances of the rare actinide nuclei and make direct measurements of the spectrum and anisotropy of electrons at energies up to approx.10 TeV, well beyond the range of the Fermi and AMS missions. OASIS has two instruments. The Energetic Trans-Iron Composition Experiment (ENTICE) instrument measures elemental composition. It resolves individual elements with atomic number (Z) from 10 to 130 and has a collecting power of 60m2.str.yrs, >20 times larger than previous instruments, and with improved resolution. The sample of 10(exp 10) GCRs collected by ENTICE will include .100 well-resolved actinides. The High Energy Particle Calorimeter Telescope (HEPCaT) is an ionization calorimeter that will extend the electron spectrum into the TeV region for the first time. It has 7.5 sq m.str.yrs of collecting power. This talk will describe the scientific objectives of the OASIS mission and its discovery potential. The mission and its two instruments which have been designed to accomplish this investigation will also be described.
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OASIS: Ocean-Atmosphere-Sea-Ice-Snowpack Interactions in Polar Regions
NASA Astrophysics Data System (ADS)
Bottenheim, J. W.; Abbatt, J.; Beine, H.; Berg, T.; Bigg, K.; Domine, F.; Leck, C.; Lindberg, S.; Matrai, P.; MacDonald, R.; McConnell, J.; Platt, U.; Raspopov, O.; Shepson, P.; Shumilov, O.; Stutz, J.; Wolff, E.
2004-05-01
While Polar regions encompass a large part of the globe, little attention has been paid to the interactions between the atmosphere and its extensive snow-covered surfaces. Recent discoveries in the Arctic and Antarctic show that the top ten centimeters of snow is not simply a white blanket but in fact is a surprisingly reactive medium for chemical reactions in the troposphere. It has been concluded that interlinked physical, chemical, and biological mechanisms, fueled by the sun and occurring in the snow, are responsible for depletion of tropospheric ozone and gaseous mercury. At the same time production of highly reactive compounds (e.g. formaldehyde, nitrogen dioxide) has been observed at the snow surface. Air-snow interactions also have an impact on the chemical composition of the snow and hence the nature and amounts of material released in terrestrial/marine ecosystems during the melting of seasonal snow-packs. Many details of these possibly naturally occurring processes are yet to be discovered. For decades humans have added waste products including acidic particles (sulphates) and toxic contaminants such as gaseous mercury and POPs (persistent organic pollutants) to the otherwise pristine snow surface. Virtually nothing is known about transformations of these contaminants in the snowpack, making it impossible to assess the risk to the polar environment, including humans. This is especially disconcerting when considering that climate change will undoubtedly alter the nature of these transformations involving snow, ice, atmosphere, ocean, and, ultimately, biota. To address these topics an interdisciplinary group of scientists from North America, Europe and Japan is developing a set of coordinated research activities under the banner of the IGBP programs IGAC and SOLAS. The program of Ocean-Atmosphere-Sea Ice-Snowpack (OASIS) interactions has been established with a mission statement aimed at determining the impact of OASIS chemical exchange on tropospheric
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Jim Faulds
2015-10-29
All datasets and products specific to the Steptoe Valley model area. Includes a packed ArcMap project (.mpk), individually zipped shapefiles, and a file geodatabase for the northern Steptoe Valley area; a GeoSoft Oasis montaj project containing GM-SYS 2D gravity profiles along the trace of our seismic reflection lines; a 3D model in EarthVision; spreadsheet of links to published maps; and spreadsheets of well data.
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Photomosaics and logs of trenches on the San Andreas Fault, Thousand Palms Oasis, California
Fumal, Thomas E.; Frost, William T.; Garvin, Christopher; Hamilton, John C.; Jaasma, Monique; Rymer, Michael J.
2004-01-01
We present photomosaics and logs of the walls of trenches excavated for a paleoseismic study at Thousand Palms Oasis (Fig. 1). The site is located on the Mission Creek strand of the San Andreas fault zone, one of two major active strands of the fault in the Indio Hills along the northeast margin of the Coachella Valley (Fig. 2). The Coachella Valley section is the most poorly understood major part of the San Andreas fault with regard to slip rate and timing of past large-magnitude earthquakes, and therefore earthquake hazard. No large earthquakes have occurred for more than three centuries, the longest elapsed time for any part of the southern San Andreas fault. In spite of this, the Working Group on California Earthquake Probabilities (1995) assigned the lowest 30-year conditional probability on the southern San Andreas fault to the Coachella Valley. Models of the behavior of this part of the fault, however, have been based on very limited geologic data. The Thousand Palms Oasis is an attractive location for paleoseismic study primarily because of the well-bedded late Holocene sedimentary deposits with abundant layers of organic matter for radiocarbon dating necessary to constrain the timing of large prehistoric earthquakes. Previous attempts to develop a chronology of paleoearthquakes for the region have been hindered by the scarcity of in-situ 14C-dateable material for age control in this desert environment. Also, the fault in the vicinity of Thousand Palms Oasis consists of a single trace that is well expressed, both geomorphically and as a vegetation lineament (Figs. 2, 3). Results of our investigations are discussed in Fumal et al. (2002) and indicate that four and probably five surface-rupturing earthquakes occurred along this part of the fault during the past 1200 years. The average recurrence time for these earthquakes is 215 ± 25 years, although interevent times may have been as short as a few decades or as long as 400 years. Thus, although the elapsed
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1981-09-01
OASIS) U Final Report This report i.s one of a set of companion documents which includes the following volumes: Volume I Executive Summary and...Northern Coastal Region of 4 the Directorate of Engineering and Systems (Direccion de Ingenieria y Sistemas ), which is responsible for maintenance of the
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NASA Astrophysics Data System (ADS)
Liu, Xingran; Shen, Yanjun
2018-03-01
Ecological deterioration in arid regions caused by agricultural development has become a global issue. Understanding water requirements of the oasis ecosystems and the influences of human agricultural activities and climate change is important for the sustainable development of oasis ecosystems and water resource management in arid regions. In this study, water requirements of the main oasis in Heihe River basin during 1986-2013 were analyzed and the amount showed a sharp increase from 10.8 × 108 m3 in 1986 to 19.0 × 108 m3 in 2013. Both human agricultural activities and climate change could lead to the increase in water requirement. To quantify the contributions of agricultural activities and climate change to the increase in water requirements, partial derivative and slope method were used. Results showed that climate change and human agricultural activities, such as oasis expansion and changes in land cropping structure, has contributed to the increase in water requirement at rates of 6.9, 58.1, and 25.3 %, respectively. Overall, human agricultural activities were the dominant forces driving the increase in water requirement. In addition, the contribution of oasis expanding to the increased water requirement was significantly greater than that of other concerned variables. This reveals that controlling the oasis scale is extremely important and effective for balancing water for agriculture and ecosystems and to achieving a sustainable oasis development in arid regions.
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NASA Astrophysics Data System (ADS)
Shaaban, Fathy A.; Abbas, Abbas M.; Atya, Magdy A.; Hafez, Mahfouz A.
2009-06-01
A Valley of Mummies was discovered recently by an Egyptian team at Bahariya Oasis, located about 380 km west of the pyramids. Four tombs were excavated, and inside them were found one hundred and five mummies (105), many of them beautifully gilded. These mummies, many sumptuously decorated with religious scenes, are the very best Roman-Period mummies ever found in Egypt. These remains are around 2000 years old, but they are in remarkable condition. A Ground-Penetrating Radar (GPR) had proved successful in detecting the cavities in resistive soil in which the mummies were found. The GPR survey conducted near the earlier-discovered tombs at Kilo-6 El-Bahariya to Farafra Oasis road is the focus of this paper. The GPR survey was conducted using the SIR-2000 attached to a 200 MHz monostatic antenna. The two areas to be surveyed were selected by the archaeologists in situ. Area one was 40 m × 40 m and Area two was 30 m × 15 m. A grid pattern survey in one direction; with one-meter profile spacing was done to both areas. In addition, a focusing survey was undertaken over the entire Area one. In addition, twenty long GPR profiles were conducted in an attempt to determine the outer, expected limits of the burial area. After the data acquisition, Reflex software was used for data processing and presentation. The final results of the radar survey: in the form of 2D radar records, time slices and 3D block diagrams; were used to guide the archaeologists during the excavation process. The excavation processes have been completed by the archaeologists, and many tombs and mummies were discovered. It is worthy to mention that, the excavations and location of tombs and cavities matched strongly with the GPR results.
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NASA Astrophysics Data System (ADS)
Song, Wei; Zhang, Ying
The Heihe River Basin (HRB) is the second largest inland river basin in the arid region of northwestern China. An agricultural oasis is a typical landscape in arid regions providing precious fertile soil, living space and ecological services. The agricultural oasis change has been one of the key issues in sustainable development in recent decades. In this paper, we examined the changes in the agricultural oasis in HRB and analyzed the socio-economic and climatic driving forces behind them. It was found that the agricultural oasis in HRB expanded by 25.11% and 14.82% during the periods of 1986-2000 and 2000-2011, respectively. Most of the newly added agricultural oases in HRB were converted from grassland (40.94%) and unused land (40.22%). The expansion in the agricultural oasis mainly occurred in the middle reaches of HRB, particularly in the counties of Shandan, Minle, Jinta and Jiuquan city. Changes in the rural labor force, annual temperature and precipitation have significant positive effects on agricultural oasis changes, while the ratio of irrigated agricultural oases has significant negative effects on agricultural oasis changes. The agricultural oasis expansion in HRB is the combined effect of human activity and climate change.
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A cephalometric study of skulls from the Bahriyah oasis
Zaki, Moushira Erfan; Soliman, Muhammad Al-Tohamy; El-Bassyouni, Hala T.
2012-01-01
Objectives: To determine the craniofacial characteristics of crania from the Bahariyah oasis dating from the Greco-Roman period and to compare their cephalometric traits with other ancient Egyptian samples from various time periods and to evaluate sexual dimorphism. Materials and Methods: The sample comprised 149 skulls (90 males and 59 females), belonging to the Greco-Roman (332 B.C. – 395 A.D.). Lateral and postero-anterior cephalograms were taken. Sixteen linear measurements were analyzed and six indices were calculated. Results: Significant differences were found between males and females almost in all measurements. All male measurements were greater than those of the females. The study shows notable differences in the craniofacial parameters of the present sample as compared to other ancient Egyptians from various periods and from various geographical areas. Conclusion: The present study suggests that the studied crania from Bahriyah oasis had a specific craniometric phenotype, which is distinguished from other Egyptian samples from different periods, suggesting some migration could have occurred along the Egyptian Nile Valley over various times. PMID:23741149
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NASA Astrophysics Data System (ADS)
Hewaidy, Abdel Galil A.; Farouk, Sherif; Bazeen, Youssef S.
2017-12-01
The Maastrichtian-Paleocene succession at the Dakhla Oasis is marked by the presence of a typical Nile Valley Facies represented by the Dakhla and Tarawan formations in Edmonstone and Qur El Malik sections in the central and western parts of the oasis, while a mixed Nile Valley and Garra Al-Arbain facies represented by Dakhla, Kurkur and Tarawan formations in Teneida section in the eastern part of the oasis adjacent to the Abu Tartur Plateau. These sections were examined for their foraminiferal contents, lithologic characters and stratigraphic boundaries. The distribution of foraminifera in the studied sections is variable and inconstant, as the planktonics are concentrated only at certain levels, which may be considered as a time intervals of transgression and maximum flooding surfaces. Eight planktonic biozones are distinguished in this work; of theses two are of Maastrichtain age and six are of Paleocene age. Eight 3rd order depositional sequences are recognized in the studied Maastrichtian-Paleocene succession based on the time stratigraphic boundaries released from the planktonic foraminifera and sea level changes which are released from the paleoecologic interpretations. The distinguished sequences are subdivided into their systems tracts based on the paleobathymetric interpretations of P/B% and benthic biofacies analysis. These sequences are bounded by eight sequence boundaries (SB A - SB H) represented by unconformity surfaces and depositional hiatuses. The correlation of the sequence boundaries of the established depositional sequences with the eustatic sea level curve, suggesting that these depositional sequences were resulted from the interplay of eustatic sea-level changes and local tectonic activities.
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Development and performance of a new version of the OASIS coupler, OASIS3-MCT_3.0
NASA Astrophysics Data System (ADS)
Craig, Anthony; Valcke, Sophie; Coquart, Laure
2017-09-01
OASIS is coupling software developed primarily for use in the climate community. It provides the ability to couple different models with low implementation and performance overhead. OASIS3-MCT is the latest version of OASIS. It includes several improvements compared to OASIS3, including elimination of a separate hub coupler process, parallelization of the coupling communication and run-time grid interpolation, and the ability to easily reuse mapping weight files. OASIS3-MCT_3.0 is the latest release and includes the ability to couple between components running sequentially on the same set of tasks as well as to couple within a single component between different grids or decompositions such as physics, dynamics, and I/O. OASIS3-MCT has been tested with different configurations on up to 32 000 processes, with components running on high-resolution grids with up to 1.5 million grid cells, and with over 10 000 2-D coupling fields. Several new features will be available in OASIS3-MCT_4.0, and some of those are also described.
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ERIC Educational Resources Information Center
Franklin, Betty; Smith, Bert Kruger
This report describes Project OASIS (Older Adults Sharing Important Skills), a project designed to provide paraprofessional mental health services to nursing home residents by providing training for older adult volunteers in areas related to mental health and the elderly, supervision by OASIS staff, and consultation by staff. The background of the…
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NASA Astrophysics Data System (ADS)
Will, Andreas; Akhtar, Naveed; Brauch, Jennifer; Breil, Marcus; Davin, Edouard; Ho-Hagemann, Ha T. M.; Maisonnave, Eric; Thürkow, Markus; Weiher, Stefan
2017-04-01
We developed a coupled regional climate system model based on the CCLM regional climate model. Within this model system, using OASIS3-MCT as a coupler, CCLM can be coupled to two land surface models (the Community Land Model (CLM) and VEG3D), the NEMO-MED12 regional ocean model for the Mediterranean Sea, two ocean models for the North and Baltic seas (NEMO-NORDIC and TRIMNP+CICE) and the MPI-ESM Earth system model.We first present the different model components and the unified OASIS3-MCT interface which handles all couplings in a consistent way, minimising the model source code modifications and defining the physical and numerical aspects of the couplings. We also address specific coupling issues like the handling of different domains, multiple usage of the MCT library and exchange of 3-D fields.We analyse and compare the computational performance of the different couplings based on real-case simulations over Europe. The usage of the LUCIA tool implemented in OASIS3-MCT enables the quantification of the contributions of the coupled components to the overall coupling cost. These individual contributions are (1) cost of the model(s) coupled, (2) direct cost of coupling including horizontal interpolation and communication between the components, (3) load imbalance, (4) cost of different usage of processors by CCLM in coupled and stand-alone mode and (5) residual cost including i.a. CCLM additional computations.Finally a procedure for finding an optimum processor configuration for each of the couplings was developed considering the time to solution, computing cost and parallel efficiency of the simulation. The optimum configurations are presented for sequential, concurrent and mixed (sequential+concurrent) coupling layouts. The procedure applied can be regarded as independent of the specific coupling layout and coupling details.We found that the direct cost of coupling, i.e. communications and horizontal interpolation, in OASIS3-MCT remains below 7 % of the CCLM stand
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Perennial Antarctic lake ice: an oasis for life in a polar desert
NASA Technical Reports Server (NTRS)
Priscu, J. C.; Fritsen, C. H.; Adams, E. E.; Giovannoni, S. J.; Paerl, H. W.; McKay, C. P.; Doran, P. T.; Gordon, D. A.; Lanoil, B. D.; Pinckney, J. L.
1998-01-01
The permanent ice covers of Antarctic lakes in the McMurdo Dry Valleys develop liquid water inclusions in response to solar heating of internal aeolian-derived sediments. The ice sediment particles serve as nutrient (inorganic and organic)-enriched microzones for the establishment of a physiologically and ecologically complex microbial consortium capable of contemporaneous photosynthesis, nitrogen fixation, and decomposition. The consortium is capable of physically and chemically establishing and modifying a relatively nutrient- and organic matter-enriched microbial "oasis" embedded in the lake ice cover.
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Perennial Antarctic lake ice: an oasis for life in a polar desert.
Priscu, J C; Fritsen, C H; Adams, E E; Giovannoni, S J; Paerl, H W; McKay, C P; Doran, P T; Gordon, D A; Lanoil, B D; Pinckney, J L
1998-06-26
The permanent ice covers of Antarctic lakes in the McMurdo Dry Valleys develop liquid water inclusions in response to solar heating of internal aeolian-derived sediments. The ice sediment particles serve as nutrient (inorganic and organic)-enriched microzones for the establishment of a physiologically and ecologically complex microbial consortium capable of contemporaneous photosynthesis, nitrogen fixation, and decomposition. The consortium is capable of physically and chemically establishing and modifying a relatively nutrient- and organic matter-enriched microbial "oasis" embedded in the lake ice cover.
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NASA Astrophysics Data System (ADS)
Khalifa, M. A.; Catuneanu, O.
2008-05-01
The Lower Cenomanian Bahariya Formation in the Bahariya Oasis, Western Desert, Egypt, was deposited under two coeval environmental conditions. A fully fluvial system occurs in the southern portion of the Bahariya Oasis, including depositional products of meandering and braided streams, and a coeval fluvio-marine setting is dominant to the north. These deposits are organized into four unconformity-bounded depositional sequences, whose architecture is shaped by a complex system of incised valleys. The fluvial portion of the lower two depositional sequences is dominated by low-energy, meandering systems with a tabular geometry, dominated by overbank facies. The fluvial deposits of the upper two sequences represent the product of sedimentation within braided streams, and consist mainly of amalgamated channel-fills. The braided fluvial systems form the fill of incised valleys whose orientation follows a southeast-northwest trending direction, and which truncate the underlying sequences. Four sedimentary facies have been identified within the braided-channel systems, namely thin-laminated sandstones (Sh), cross-bedded sandstones (Sp, St), massive ferruginous sandstones (Sm) and variegated mudstones (Fm). The exposed off-channel overbank facies of the meandering systems include floodplain (Fm) and crevasse splay (Sl) facies. The fluvio-marine depositional systems consist of interbedded floodplain, coastal and shallow-marine deposits. The floodplain facies include fine-grained sandstones (Sf), laminated siltstones (Stf) and mudstones (Mf) that show fining-upward cycles. The coastal to shallow-marine facies consist primarily of mudstones (Mc) and glauconitic sandstones (Gc) organized vertically in coarsening-upward prograding cyclothems topped by thin crusts of ferricrete (Fc). The four depositional sequences are present across the Bahariya Oasis, albeit with varying degrees of preservation related to post-depositional erosion associated with the formation of sequence
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Jackson, Tracie R.; Fenelon, Joseph M.
2018-05-31
This report identifies water-level trends in wells and provides a conceptual framework that explains the hydrologic stresses and factors causing the trends in the Pahute Mesa–Oasis Valley (PMOV) groundwater basin, southern Nevada. Water levels in 79 wells were analyzed for trends between 1966 and 2016. The magnitude and duration of water-level responses to hydrologic stresses were analyzed graphically, statistically, and with water-level models.The conceptual framework consists of multiple stress-specific conceptual models to explain water-level responses to the following hydrologic stresses: recharge, evapotranspiration, pumping, nuclear testing, and wellbore equilibration. Dominant hydrologic stresses affecting water-level trends in each well were used to categorize trends as nonstatic, transient, or steady state.The conceptual framework of water-level responses to hydrologic stresses and trend analyses provide a comprehensive understanding of the PMOV basin and vicinity. The trend analysis links water-level fluctuations in wells to hydrologic stresses and potential factors causing the trends. Transient and steady-state trend categorizations can be used to determine the appropriate water-level data for groundwater studies.
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[Study on ecological risk assessment technology of fluoride pollution from arid oasis soil].
Xue, Su-Yin; Li, Ping; Wang, Sheng-Li; Nan, Zhong-Ren
2014-03-01
According to translocation regulation of fluoride in the typical oasis soil-plant system under field, an ecological risk assessment model of fluoride was established, and this model was used to assess ecological risk to fluoride pollution from suburban oasis soils in Baiyin City, which was specifically expressed with the potential ecological risk of bioavailability (ER(bc)) model to assess ecological risk of fluoride pollution in oasis regions. Results showed that the ecological risk indices of fluoride pollution from this region were 1.37-24.81, the level of risk at most sites was high to very high, the average ecological risk index was 11.28, belonged to very high risk. This indicated that in the suburb soil of Baiyin City needs to be concerned about the remediation of fluoride pollution.
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Varela, Héctor H; Cocilovo, Jose A; Fuchs, María L; O'Brien, Tyler G
2014-12-01
The existing biocultural links are analyzed among ancient inhabitants of the Cochabamba valleys (Bolivia) from the Formative and Tiwanaku periods, coastal and inland Azapa region (Chile) from the Late Archaic to the Late periods, and the Atacama Desert oases (Chile) from the Formative period to the time of European contact. Craniometric information obtained from a sample of 565 individuals from different sites of the studied regions was evaluated using methods derived from quantitative genetics and multivariate statistical analysis techniques. It is shown that during the Formative and Tiwanaku periods inhabitants of the Cochabamba valleys maintained contact with the population of northern Chile. This contact was more fluid with the people from the interior valley of Azapa than it was with the settlers of San Pedro Atacama (SPA). An important biological affinity in the Late Period between the inhabitants of the Azapa valley and the late SPA groups is also examined. The Late-Inca Catarpe SPA sample shows a broad genetic variability shared with the majority of the groups studied. The results reaffirm the differences between the coastal and interior Azapa valley groups and strengthen the hypothesis of two pathways to populating the south central Andean area. The divergence observed among subpopulations can be explained by the spatiotemporal dispersion between them, genetic drift dispersion compensated by the action of gene flow, and cultural norms that regulate within group mating. © 2014 Wiley Periodicals, Inc.
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EPA Region 1 - Valley Depth in Meters
Raster of the Depth in meters of EPA-delimited Valleys in Region 1.Valleys (areas that are lower than their neighbors) were extracted from a Digital Elevation Model (USGS, 30m) by finding the local average elevation, subtracting the actual elevation from the average, and selecting areas where the actual elevation was below the average. The landscape was sampled at seven scales (circles of 1, 2, 4, 7, 11, 16, and 22 km radius) to take into account the diversity of valley shapes and sizes. Areas selected in at least four scales were designated as valleys.
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2017-12-08
NASA image acquired Feb. 9, 2011 Less than 5 percent of Algeria’s land surface is suitable for growing crops, and most precipitation falls on the Atlas Mountains along the coast. Inland, dust-laden winds blow over rocky plains and sand seas. However, in north central Algeria—off the tip of Grand Erg Occidental and about 450 kilometers (280 miles) south of Algiers—lies a serpentine stretch of vegetation. It is the M’zab Valley, filled with palm groves and dotted with centuries-old settlements. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured this image of M’zab Valley on February 9, 2011. ASTER combines infrared, red, and green wavelengths of light. Bare rock ranges in color from beige to peach. Buildings and paved surfaces appear gray. Vegetation is red, and brighter shades of red indicate more robust vegetation. This oasis results from water that is otherwise in short supply in the Sahara Desert, thanks to the valley’s approximately 3,000 wells. Chemical analysis of Algerian aquifers, as well studies of topography in Algeria and Tunisia, suggest this region experienced a cooler climate in the late Pleistocene, and potentially heavy monsoon rains earlier in the Holocene. The M’zab region shows evidence of meandering rivers and pinnate drainage patterns. The vegetation lining M’zab Valley highlights this old river valley’s contours. Cool summer temperatures and monsoon rains had long since retreated from the region by eleventh century, but this valley nevertheless supported the establishment of multiple fortified settlements, or ksours. Between 1012 A.D. and 1350 A.D., locals established the ksours of El-Atteuf, Bounoura, Melika, Ghardaïa, and Beni-Isguen. Collectively these cities are now a United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage site. NASA Earth Observatory image by Robert Simmon and Jesse Allen, using data from the GSFC
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[Dynamics of ecological footprints of agricultural region in Hexi oasis of Gansu Province].
Lin, Haiming; Xie, Peng
2004-05-01
This paper studied the dynamics of ecological footprints (EF), degree of sustainable development and its tendency of Hexi oasis agricultural region in Gansu. The results showed that the EF displayed an increasing trend from 0.426 hm2 to 2.158 hm2 in 1949-2000, which was 0.693 hm2 in 1949-1970, 1.029 hm2 in 1975-1980, and 2.288 hm2 in 1985-2000. The ecological capacity (EC) was also increased from 0.550 hm2 in 1949 to 1.762 hm2 in 2000. Comparing with EF, the EC increased at low speed, which reached 0.782 hm2 in 1949-1970 and 1.715 hm2 in 1975-2000. Meanwhile, the sustainable development of Hexi region maintained ecological remainder during 1949-1975. However, it emerged ecological deficit in 1980, and resumed in 1985. The sustainable development of Hexi region has been successive ecological deficit since 1991. The degree was keeping negative increment at acceleration, and got to -0258 hm2 in 1991-2000. These results showed that the regional economic development of Hexi region was far away from sustainable development, and was in no-sustainable state.
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42 CFR 484.20 - Condition of participation: Reporting OASIS information.
Code of Federal Regulations, 2014 CFR
2014-10-01
... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...
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42 CFR 484.20 - Condition of participation: Reporting OASIS information.
Code of Federal Regulations, 2012 CFR
2012-10-01
... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...
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42 CFR 484.20 - Condition of participation: Reporting OASIS information.
Code of Federal Regulations, 2013 CFR
2013-10-01
... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...
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42 CFR 484.20 - Condition of participation: Reporting OASIS information.
Code of Federal Regulations, 2011 CFR
2011-10-01
... layout, edit specifications, and data dictionary, and that includes the required OASIS data set. [64 FR... OASIS data collected in accordance with § 484.55. (a) Standard: Encoding and transmitting OASIS data. An... beneficiary. (b) Standard: Accuracy of encoded OASIS data. The encoded OASIS data must accurately reflect the...
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Orbiting Astrophysical Spectrometer in Space (OASIS)
NASA Technical Reports Server (NTRS)
Adams, James H.
2008-01-01
This viewgraph presentation reviews the OASIS mission. The contents include: 1) Introduction to Cosmic Rays; 2) How are they accelerated?; 3) OASIS Objectives; 4) 5) HEPCaT Instrument; and 6) ENTICE Instrument
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The classification and assessment of vulnerability of man-land system of oasis city in arid area
NASA Astrophysics Data System (ADS)
Gao, Chao; Lei, Jun; Jin, Fengjun
2013-12-01
Oasis city system is the center of the man-land relationship in arid area and it is the most influential spatial and temporal multiple dynamic system. Oasis city system is not only the largest area where artificial disturbances occur at a regional scale but also the most concentrated area of human activity in arid area. In this study, we developed an applicable and convenient method to assess vulnerability of man-land system of oasis cities with vulnerability indicator system, respectively evaluating the sensitivity, adaptability and vulnerability of the eco-environment system, the economic system and the social system. The results showed that the sensitivity and vulnerability of oasis cities in Xinjiang, China have significant differences while their adaptability does little. In order to find the inherent differences in the vulnerability of oasis cities, triangle methodology has been adopted to divide Xinjiang oasis cities into five types. Some adaptive developing policies specific for individual cities are also proposed based on their vulnerability type and constraining factors.
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OASIS modulates hypoxia pathway activity to regulate bone angiogenesis
Cui, Min; Kanemoto, Soshi; Cui, Xiang; Kaneko, Masayuki; Asada, Rie; Matsuhisa, Koji; Tanimoto, Keiji; Yoshimoto, Yuki; Shukunami, Chisa; Imaizumi, Kazunori
2015-01-01
OASIS/CREB3L1, an endoplasmic reticulum (ER)-resident transcription factor, plays important roles in osteoblast differentiation. In this study, we identified new crosstalk between OASIS and the hypoxia signaling pathway, which regulates vascularization during bone development. RT-PCR and real-time PCR analyses revealed significant decreases in the expression levels of hypoxia-inducible factor-1α (HIF-1α) target genes such as vascular endothelial growth factor A (VEGFA) in OASIS-deficient (Oasis−/−) mouse embryonic fibroblasts. In coimmunoprecipitation experiments, the N-terminal fragment of OASIS (OASIS-N; activated form of OASIS) bound to HIF-1α through the bZIP domain. Luciferase assays showed that OASIS-N promoted the transcription activities of a reporter gene via a hypoxia-response element (HRE). Furthermore, the expression levels of an angiogenic factor Vegfa was decreased in Oasis−/− osteoblasts. Immunostaining and metatarsal angiogenesis assay showed retarded vascularization in bone tissue of Oasis−/− mice. These results suggest that OASIS affects the expression of HIF-1α target genes through the protein interaction with HIF-1α, and that OASIS-HIF-1α complexes may play essential roles in angiogenesis during bone development. PMID:26558437
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Entomofauna of Ziban Oasis, Biskra, Algeria
Deghiche-Diab, Nassima; Porcelli, Francisco; Belhamra, Mohamed
2015-01-01
An inventory was carried out at five stations in the oasis of Ziban, an oasis that is characterized by its high-quality dates, in order to study the relationships between the oasis ecosystem and its insect fauna. Specimens were sampled using pitfall traps containing ethylene glycol as a preservative. In total, 115 arthropod species were collected during 5 months of survey. These species belonged to 61 families, 17 orders, and 4 classes (12 orders from Insecta, 3 from Arachnida, 1 from Chilopoda, and 1 from Malocostraca). The most represented insect orders were Coleoptera (44.42%), Hymenoptera (20.86%), and Lepidoptera (7.87%). Represented in the collections were phytophagous, omnivorous, and predator/parasite species. Given the large number of species collected, and the largely unknown relationships existing between the various ecological groups, this study is a first step in the description of the oasis entomofauna. PMID:25855607
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Quaternary history of the Kiseiba Oasis region, southern Egypt
NASA Astrophysics Data System (ADS)
Maxwell, Ted A.; Haynes, C. Vance; Nicoll, Kathleen; Johnston, Andrew K.; Grant, John A.; Kilani, Ali
2017-12-01
Kiseiba Oasis and depression are located in southern Egypt between the Selima Sand Sheet to the west and the Nile to the east, an important area that hosted Late Cenozoic drainage, Middle Pleistocene lakes, and numerous Paleolithic and Neolithic cultural sites. A synthesis of orbital data, field surveying and near-surface stratigraphy provides new insights into the Quaternary history of this region. Shuttle Imaging Radar data show a complex of fluvial channels that are due to stringers of surficial fluvial lag, subsurface fluvial deposits, and areas of deep alluvium. Three topographic surfaces are described: 1) the Atmur El-Kibeish, above 230 m elevation, which displays a linear pattern of light radar returns, possibly formed from northeast drainage; 2) the Acheulean Surface, at 200 m elevation, that has dark radar patterns resulting from thick alluvium bounded by pebble sand and calcrete strata, and 3) the Kiseiba Surface, below 190 m, that has a complex series of surface and subsurface fluvial and aeolian sediments. Initial drainage from the Early through Middle Pleistocene was to the northeast, which may have lasted through the Last Interglacial. Later reworking of sediments during the Last Glacial Maximum and the Holocene resulted in topographic inversion, with any subsequent local drainage on the Kiseiba Surface to the southwest, towards the Kiseiba Scarp.
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DOT National Transportation Integrated Search
2009-04-01
The Delaware Valley Regional Planning Commission uses a systematic process for managing traffic congestion and monitoring transportation system performance in the Philadelphia metropolitan region. Guided by an advisory team of stakeholders, the agenc...
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Source regions and water release mechanisms of Martian Valley Networks
NASA Astrophysics Data System (ADS)
Jaumann, R.; Reiss, D.; Sander, T.; Gwinner, K.; Roatsch, T.; Matz, K.-D.; Hauber, E.; Mertens, V.; Hoffmann, H.; Neukum, G.; HRSC Co-Investigator Team
Martian valley networks have been cited as the best evidence that Mars maintained flow of liquid water across the surface. Although internal structures associated with a fluvial origin within valleys like inner channels, terraces, slip-off and undercut slopes are extremely rare on Mars (Carr and Malin, 2000) such features can be identified in high-resolution imagery (e.g. Malin and Edgett, 2001; Jaumann et al., 2005). However, besides internal features the source regions are an important indicator for the flow processes in Martian valleys because they define the drainage area and thus constrain the amount of available water for eroding the valley network. Furthermore, the morphology of the source regions and their topographic characteristics provide information about the origin of the water. On Mars valley networks are thought to be formed by retreating erosion where the water is supplied from the sub-surface. However, the mechanisms that are responsible for the release of ground water are poorly understood. The three dimensional highly resolved data of the High Resolution Stereo Camera (HRSC) on the Mars Express Mission (Neukum et al., 2004) allow the detailed examination of valley network source regions. A valley network in the western Lybia Montes region valley between 1.4°N to 3.5°N and 81.6°E to 82.5°E originates at a highland mountain region and drains down to Isidis Planitia over a distance of 400 km. Most of its distance the valley exhibits an interior channel that allows to constraint discharge and erosion budgets (Jaumann, et al., 2005). The valley was formed in the Noachian/Hesperian between 3.7 and 3.3 billion years. However, discharge and erosion budgets restrict the erosion time to a few million years in total, indicating single events rather than continuous flow over long periods. The source region of the valley is covered by a series of lava flows. Even the upstream part of the valley is covered by lava flows that cover the interior channel
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Geological heritage diversity in the Faiyum Oasis (Egypt): A comprehensive assessment
NASA Astrophysics Data System (ADS)
Sallam, Emad S.; Fathy, Esraa E.; Ruban, Dmitry A.; Ponedelnik, Alena A.; Yashalova, Natalia N.
2018-04-01
The Faiyum Oasis in the Western Desert of Egypt is famous for its palaeontological localities (Cenozoic whales, primates, etc.) of global importance, but its geological heritage has been not studied in the modern theoretical frame. The new investigation based on the field studies and the literature review permits comprehensive assessment of the geological heritage diversity in this oasis. For this purposes, unique geological features are inventoried with establishment of their geological essence, rank, relative abundance, and intrinsic diversity. As a result, the existence of ten geological heritage types in the Faiyum Oasis is found. These include palaeontological, palaeogeographical, geomorphological, stratigraphical, sedimentary (merged with mineralogical), hydrological coupled with geochemical, igneous, and economical types. From them, the palaeontological and palaeogeographical types are ranked globally, and the geomorphological and hydrological types are ranked nationally. The other types are either of regional (provincial) or local importance. Some hills and cliffs can serve as viewpoint sites for observation of the local geological landscape. The relative abundance and the intrinsic diversity of the unique geological features vary between low and high. Generally, the concentration of this geological heritage in the Faiyum Oasis permits recognition of the geodiversity hotspot that requires conservation and use for tourism purposes. The protected areas located in the oasis and the existing tourism programs do not offer geoconservation and geotourism activities for the entire hotspot. The possible solution of this problem would be creation of a large geopark similar in its design to the Jeju Island Geopark in South Korea. There are important premises for geotourism development in the Faiyum Oasis and its combination with the archaeological and industrial tourism. Nature conservation failures in this geopark should be avoided; some recommendations are given on
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False color image of Safsaf Oasis in southern Egypt
NASA Technical Reports Server (NTRS)
1994-01-01
This is a false color image of the uninhabited Safsaf Oasis in southern Egypt near the Egypt/Sudan border. It was produced from data obtained from the L-band and C-band radars that are part of the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar onboard the Shuttle Endeavour on April 9, 1994. The image is centered at 22 degrees North latitude, 29 degrees East longitude. It shows detailed structures of bedrock, and the dark blue sinuous lines are braided channels that occupy part of an old broad river valley. Virtually everything visible on this radar composite image cannot be seen either when standing on the ground or when viewing photographs or satellite images such as Landsat. The Jet Propulsion Laboratory alternative photo number is P-43920.
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From Workbook to Web: Building an Information Literacy OASIS.
ERIC Educational Resources Information Center
Rosen, Jeff; Castro, Gina M.
2002-01-01
Describes a Web-based information literacy tutorial, OASIS (Online Advancement of Student Information Skills), developed at San Francisco State University. Discussion includes: core competencies identified; design structure and content; planning and marketing; problems and partnerships in the pilot year of OASIS; restructuring the OASIS tutorial;…
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40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...
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40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2014 CFR
2014-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...
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40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...
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40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2013 CFR
2013-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...
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40 CFR 81.48 - Champlain Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2012 CFR
2012-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.48 Champlain Valley Interstate Air Quality Control Region. The Champlain Valley Interstate Air Quality Control Region (Vermont-New York) has been revised to consist of the...
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OASIS: Prototyping Graphical Interfaces to Networked Information.
ERIC Educational Resources Information Center
Buckland, Michael K.; And Others
1993-01-01
Describes the latest modifications being made to OASIS, a front-end enhancement to the University of California's MELVYL online union catalog. Highlights include the X Windows interface; multiple database searching to act as an information network; Lisp implementation for flexible data representation; and OASIS commands and features to help…
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Oasis: online analysis of small RNA deep sequencing data.
Capece, Vincenzo; Garcia Vizcaino, Julio C; Vidal, Ramon; Rahman, Raza-Ur; Pena Centeno, Tonatiuh; Shomroni, Orr; Suberviola, Irantzu; Fischer, Andre; Bonn, Stefan
2015-07-01
Oasis is a web application that allows for the fast and flexible online analysis of small-RNA-seq (sRNA-seq) data. It was designed for the end user in the lab, providing an easy-to-use web frontend including video tutorials, demo data and best practice step-by-step guidelines on how to analyze sRNA-seq data. Oasis' exclusive selling points are a differential expression module that allows for the multivariate analysis of samples, a classification module for robust biomarker detection and an advanced programming interface that supports the batch submission of jobs. Both modules include the analysis of novel miRNAs, miRNA targets and functional analyses including GO and pathway enrichment. Oasis generates downloadable interactive web reports for easy visualization, exploration and analysis of data on a local system. Finally, Oasis' modular workflow enables for the rapid (re-) analysis of data. Oasis is implemented in Python, R, Java, PHP, C++ and JavaScript. It is freely available at http://oasis.dzne.de. stefan.bonn@dzne.de Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press.
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Effects of climate change on phenological trends and seed cotton yields in oasis of arid regions.
Huang, Jian; Ji, Feng
2015-07-01
Understanding the effects of climatic change on phenological phases of cotton (Gossypium hirsutum L.) in oasis of arid regions may help optimize management schemes to increase productivity. This study assessed the impacts of climatic changes on the phenological phases and productivity of spring cotton. The results showed that climatic warming led the dates of sowing seed, seeding emergence, three-leaf, five-leaf, budding, anthesis, full bloom, cleft boll, boll-opening, boll-opening filling, and stop-growing become earlier by 24.42, 26.19, 24.75, 23.28, 22.62, 15.75, 14.58, 5.37, 2.85, 8.04, and 2.16 days during the period of 1981-2010, respectively. The growth period lengths from sowing seed to seeding emergence and from boll-opening to boll-opening filling were shortened by 1.76 and 5.19 days, respectively. The other growth period lengths were prolonged by 2-9.71 days. The whole growth period length was prolonged by 22.26 days. The stop-growing date was delayed by 2.49-3.46 days for every 1 °C rise in minimum, maximum, and mean temperatures; however, other development dates emerged earlier by 2.17-4.76 days. Rising temperatures during the stage from seeding emergence to three-leaf reduced seed cotton yields. However, rising temperatures increased seed cotton yields in the two stages from anthesis to cleft boll and from boll-opening filling to the stop-growing. Increasing accumulated temperatures (AT) had different impacts on different development stages. During the vegetative phase, rising AT led to reduced seed cotton yields, but rising AT during reproductive stage increased seed cotton yields. In conclusion, climatic warming helpfully obtained more seed cotton yields in oasis of arid regions in northwest China. Changing the sowing date is another way to enhance yields for climate change in the future.
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ERIC Educational Resources Information Center
Bircher, Lisa S.; Sansenbaugher, Bonnie
2017-01-01
This article describes an elementary science summer day camp at East Palatine High School in East Palestine, Ohio, for students in grades K-4, aided by high school (grades 9-12) student mentors. The school's Outdoor Area for Studies in Science (OASIS) is used for formal and informal studies in science for an elementary science camp week. The camp…
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Steinkampf, W.C.
2000-01-01
Yucca Mountain, located ~100 mi northwest of Las Vegas, Nevada, has been designated by Congress as a site to be characterized for a potential mined geologic repository for high-level radioactive waste. This field trip will examine the regional geologic and hydrologic setting for Yucca Mountain, as well as specific results of the site characterization program, The first day focuses on the regional seeing with emphasis on current and paleo hydrology, which are both of critical concern for predicting future performance of a potential repository. Morning stops will be in southern Nevada and afternoon stops will be in Death Valley. The second day will be spent at Yucca Mountain. The filed trip will visit the underground testing sites in the "Exploratory Studies Facility" and the "Busted Butte Unsaturated Zone Transport Field Test" plus several surface-based testing sites. Much of the work at the site has concentrated on studies of the unsaturated zone, and element of the hydrologic system that historically has received little attention. Discussions during the second day will comprise selected topics of Yucca Mountain geology, mic hazard in the Yucca Mountain area. Evening discussions will address modeling of regional groundwater flow, the geology and hydrology of Yucca Mountain to the performance of a potential repository. Day 3 will examine the geologic framework and hydrology of the Pahute Mesa-Oasis Valley Groundwater Basin and then will continue to Reno via Hawthorne, Nevada and the Walker Lake area.
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Oasis 2: improved online analysis of small RNA-seq data.
Rahman, Raza-Ur; Gautam, Abhivyakti; Bethune, Jörn; Sattar, Abdul; Fiosins, Maksims; Magruder, Daniel Sumner; Capece, Vincenzo; Shomroni, Orr; Bonn, Stefan
2018-02-14
Small RNA molecules play important roles in many biological processes and their dysregulation or dysfunction can cause disease. The current method of choice for genome-wide sRNA expression profiling is deep sequencing. Here we present Oasis 2, which is a new main release of the Oasis web application for the detection, differential expression, and classification of small RNAs in deep sequencing data. Compared to its predecessor Oasis, Oasis 2 features a novel and speed-optimized sRNA detection module that supports the identification of small RNAs in any organism with higher accuracy. Next to the improved detection of small RNAs in a target organism, the software now also recognizes potential cross-species miRNAs and viral and bacterial sRNAs in infected samples. In addition, novel miRNAs can now be queried and visualized interactively, providing essential information for over 700 high-quality miRNA predictions across 14 organisms. Robust biomarker signatures can now be obtained using the novel enhanced classification module. Oasis 2 enables biologists and medical researchers to rapidly analyze and query small RNA deep sequencing data with improved precision, recall, and speed, in an interactive and user-friendly environment. Oasis 2 is implemented in Java, J2EE, mysql, Python, R, PHP and JavaScript. It is freely available at https://oasis.dzne.de.
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NASA Technical Reports Server (NTRS)
Duke, Michael B.; Niehoff, John
1989-01-01
The 'lunar oasis' emphasizes development toward self-sufficiency in order to reduce dependence on the earth for resupply, and to enable expansion utilizing indigeneous resources. The oasis phase includes: (1) habitation and work facilities for 10 people, (2) capability for extraction of volatile consumables (H2O, O2, N2, etc.) from indigenous resources for resupply of losses and filling of reservoirs, and (3) a highly closed life support system, including food production. In the consolidation phase, the base grows from 10 to 30 crewmembers. Lunar resources are used for expanding the lunar foothold, including construction of habitats, extraction of metals for the fabrication of products for maintenance and repair, and expansion of the power system. The strategy does not produce propellants for space transportation. A 10-year scenario is laid out, which contains all elements needed to allow the base to enter a self-expanding utilization phase. Three lunar missions yer year, two cargo missions and one crew flight, are required. At the end of a decade, the base is producing more than it requires for its continued support, although it is unlikely to be completely self-sufficient.
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NASA Astrophysics Data System (ADS)
Catuneanu, O.; Khalifa, M. A.; Wanas, H. A.
2006-08-01
The Lower Cenomanian Bahariya Formation corresponds to a second-order depositional sequence that formed within a continental shelf setting under relatively low-rate conditions of positive accommodation (< 200 m during 3-6 My). This overall trend of base-level rise was interrupted by three episodes of base-level fall that resulted in the formation of third-order sequence boundaries. These boundaries are represented by subaerial unconformities (replaced or not by younger transgressive wave ravinement surfaces), and subdivide the Bahariya Formation into four third-order depositional sequences. The construction of the sequence stratigraphic framework of the Bahariya Formation is based on the lateral and vertical changes between shelf, subtidal, coastal and fluvial facies, as well as on the nature of contacts that separate them. The internal (third-order) sequence boundaries are associated with incised valleys, which explain (1) significant lateral changes in the thickness of incised valley fill deposits, (2) the absence of third-order highstand and even transgressive systems tracts in particular areas, and (3) the abrupt facies shifts that may occur laterally over relatively short distances. Within each sequence, the concepts of lowstand, transgressive and highstand systems tracts are used to explain the observed lateral and vertical facies variability. This case study demonstrates the usefulness of sequence stratigraphic analysis in understanding the architecture and stacking patterns of the preserved rock record, and helps to identify 13 stages in the history of base-level changes that marked the evolution of the Bahariya Oasis region during the Early Cenomanian.
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Recreational value of an oasis in Oman.
Zekri, Slim; Mbaga, Msafiri; Fouzai, Ayoub; Al-Shaqsi, Saif
2011-07-01
Increasing demand for water to develop non-agricultural activities is causing water to be diverted to high-value uses at the expense of irrigation. However, agriculture provides a flow of amenities in the desert environment which are not either accounted or paid. Oases are spread all over the globe and are threatened for various reasons among which is the high pressure of demand for fresh water. This paper estimates the recreation use value of an oasis. The paper is based on the Misfat Al-Abryeen oasis in Oman, a man-made area of streams and woodland. The travel cost method is used through an on-site questionnaire distributed to 230 visitors. Around 75% of visitors to the oasis also visited other historical or ecological sites during the same day-trip. The econometric model is estimated using negative binomial regression with endogenous stratification. The average consumer surplus, or benefit, from visiting Misfat Al-Abryeen is estimated at US$ 104.74 per individual per trip. The total social benefit from this oasis is estimated at $366,590 per year. These results underscore the importance of the role played by irrigated agriculture in the provision of amenity services for the tourism sector in a desert environment. The sustainability of the irrigation activity depends on the recognition of the recreation role of oases and the transfer of part of these benefits to the farmers who maintain the irrigation system. The implementation of an entrance fee to the oasis might increase farmers' profit by 6-21%.
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Recreational Value of an Oasis in Oman
NASA Astrophysics Data System (ADS)
Zekri, Slim; Mbaga, Msafiri; Fouzai, Ayoub; Al-Shaqsi, Saif
2011-07-01
Increasing demand for water to develop non-agricultural activities is causing water to be diverted to high-value uses at the expense of irrigation. However, agriculture provides a flow of amenities in the desert environment which are not either accounted or paid. Oases are spread all over the globe and are threatened for various reasons among which is the high pressure of demand for fresh water. This paper estimates the recreation use value of an oasis. The paper is based on the Misfat Al-Abryeen oasis in Oman, a man-made area of streams and woodland. The travel cost method is used through an on-site questionnaire distributed to 230 visitors. Around 75% of visitors to the oasis also visited other historical or ecological sites during the same day-trip. The econometric model is estimated using negative binomial regression with endogenous stratification. The average consumer surplus, or benefit, from visiting Misfat Al-Abryeen is estimated at US 104.74 per individual per trip. The total social benefit from this oasis is estimated at 366,590 per year. These results underscore the importance of the role played by irrigated agriculture in the provision of amenity services for the tourism sector in a desert environment. The sustainability of the irrigation activity depends on the recognition of the recreation role of oases and the transfer of part of these benefits to the farmers who maintain the irrigation system. The implementation of an entrance fee to the oasis might increase farmers' profit by 6-21%.
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EPA Region 1 - Map Layers for Valley ID Tool (Hosted Feature Service)
The Valley Service Feature Layer hosts spatial data for EPA Region 1's Valley Identification Tool. These layers contain attribute information added by EPA R1 GIS Center to help identify populated valleys:- Fac_2011NEI: Pollution sources selected from the National Emissions Inventory (EPA, 2011).- NE_Towns_PopValleys: New England Town polygons (courtesy USGS), with Population in Valleys and Population Density in Valleys calculated by EPA R1 GIS, from 2010 US Census blocks. - VT_E911: Vermont residences (courtesy VT Center for Geographic Information E-911).
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ERIC Educational Resources Information Center
Stanford Univ., CA.
Recognizing the need to balance generality and economy in system costs, the Project INFO team at Stanford University developing OASIS has sought to provide generalized and powerful computer support within the normal range of operating and analytical requirements associated with university administration. The specific design objectives of the OASIS…
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Demonstration of obstacle avoidance system (OASYS) symbology in full mission simulation
NASA Astrophysics Data System (ADS)
Sharkey, Thomas J.
1994-06-01
The U. S. Army Aeroflightdynamics Directorate's (AFDD) Crew Station Research and Development Branch (CSRDB) conducted a multiphase effort to develop symbology displaying information from the Obstacle Avoidance System (OASYS) on the Aviator's Night Vision System (ANVIS) Head Up Display (HUD). The first phase of this program used static symbology displayed on a workstation to identify the types of information required from OASYS by the pilot. The second phase used a low-fidelity, pilot-in-the-loop simulation to evaluate fourteen different symbology-drive law combinations. Based on the results of phases 1 and 2 three candidate symbologies were selected, along with the baseline symbology developed by the OASYS contractor, for evaluation in full mission simulation. In addition, a full-daylight, full field-of-view condition and Night Vision Goggle (NVG) condition, both without OASYS symbology, were used as control conditions. The environmental conditions (e.g., ambient illumination, visual range) and task requirements (e.g., altitude and airspeed) used in the simulation were selected to severely tax the symbology. Reliable differences in performance between symbology conditions were found. Two of the symbologies developed during the earlier phases of this program resulted in reduced frequencies of ground strikes compared to OASYS baseline and NVG only conditions. The frequency of close approaches to wires was lower with the symbology developed in this program than with the baseline symbology. All OASYS symbologies improved performance relative to the NVG control condition. It is recommended that the OASYS symbology and drive laws developed during this program be used during OASYS flight tests.
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Long-term outcomes of the Stop Traumatic OASI Morbidity Project (STOMP).
Basu, Maya; Smith, Dot
2018-06-09
To evaluate long-term sustainability of the Stop Traumatic OASI Morbidity Project (STOMP) in reducing the incidence of obstetric anal sphincter injury (OASI). A prospective observational study of women undergoing vaginal delivery at a UK district general hospital between September 1, 2014, and February 28, 2017. The principles of STOMP involve encouraging upright positioning, verbal coaching to avoid expulsive pushing and to slow down delivery, and tactile support to the vertex to judge speed and slow down delivery. After a training period, STOMP was implemented for all vaginal deliveries. Clinical and demographic data on women affected by OASI were collected across a 30-month period. The primary outcome measure was the incidence of OASI. There were 8782 vaginal deliveries during the 30-month period after implementation of STOMP. There was a significant decrease in the mean incidence of OASI relative to the 9 months before implementation (P<0.001). There was a significant decrease in the incidence of OASI for both spontaneous vaginal and instrumental deliveries (both P<0.05). There was no change in the frequency of episiotomy. Implementation of STOMP led to a significant decrease in OASI, confirming the sustainability of this approach to improve outcomes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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OASIS: A Data Fusion System Optimized for Access to Distributed Archives
NASA Astrophysics Data System (ADS)
Berriman, G. B.; Kong, M.; Good, J. C.
2002-05-01
The On-Line Archive Science Information Services (OASIS) is accessible as a java applet through the NASA/IPAC Infrared Science Archive home page. It uses Geographical Information System (GIS) technology to provide data fusion and interaction services for astronomers. These services include the ability to process and display arbitrarily large image files, and user-controlled contouring, overlay regeneration and multi-table/image interactions. OASIS has been optimized for access to distributed archives and data sets. Its second release (June 2002) provides a mechanism that enables access to OASIS from "third-party" services and data providers. That is, any data provider who creates a query form to an archive containing a collection of data (images, catalogs, spectra) can direct the result files from the query into OASIS. Similarly, data providers who serve links to datasets or remote services on a web page can access all of these data with one instance of OASIS. In this was any data or service provider is given access to the full suite of capabilites of OASIS. We illustrate the "third-party" access feature with two examples: queries to the high-energy image datasets accessible from GSFC SkyView, and links to data that are returned from a target-based query to the NASA Extragalactic Database (NED). The second release of OASIS also includes a file-transfer manager that reports the status of multiple data downloads from remote sources to the client machine. It is a prototype for a request management system that will ultimately control and manage compute-intensive jobs submitted through OASIS to computing grids, such as request for large scale image mosaics and bulk statistical analysis.
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40 CFR 81.81 - Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Designation of Air Quality Control Regions § 81.81 Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region. The Merrimack Valley Southern New Hampshire Interstate Air Quality Control Region (Massachusetts-New Hampshire) consists of the territorial area encompassed by the boundaries of the following...
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40 CFR 81.81 - Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Designation of Air Quality Control Regions § 81.81 Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region. The Merrimack Valley Southern New Hampshire Interstate Air Quality Control Region (Massachusetts-New Hampshire) consists of the territorial area encompassed by the boundaries of the following...
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40 CFR 81.81 - Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Designation of Air Quality Control Regions § 81.81 Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region. The Merrimack Valley Southern New Hampshire Interstate Air Quality Control Region (Massachusetts-New Hampshire) consists of the territorial area encompassed by the boundaries of the following...
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40 CFR 81.81 - Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Designation of Air Quality Control Regions § 81.81 Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region. The Merrimack Valley Southern New Hampshire Interstate Air Quality Control Region (Massachusetts-New Hampshire) consists of the territorial area encompassed by the boundaries of the following...
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40 CFR 81.81 - Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Designation of Air Quality Control Regions § 81.81 Merrimack Valley-Southern New Hampshire Interstate Air Quality Control Region. The Merrimack Valley Southern New Hampshire Interstate Air Quality Control Region (Massachusetts-New Hampshire) consists of the territorial area encompassed by the boundaries of the following...
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Laczniak, Randell J.; Smith, J. LaRue; Elliott, Peggy E.; DeMeo, Guy A.; Chatigny, Melissa A.; Roemer, Gaius J.
2001-01-01
The Death Valley regional flow system (DVRFS) is one of the larger ground-water flow systems in the southwestern United States and includes much of southern Nevada and the Death Valley region of eastern California. Centrally located within the ground-water flow system is the Nevada Test Site (NTS). The NTS, a large tract covering about 1,375 square miles, historically has been used for testing nuclear devices and currently is being studied as a potential repository for the long-term storage of high-level nuclear waste generated in the United States. The U.S. Department of Energy, as mandated by Federal and State regulators, is evaluating the risk associated with contaminants that have been or may be introduced into the subsurface as a consequence of any past or future activities at the NTS. Because subsurface contaminants can be transported away from the NTS by ground water, components of the ground-water budget are of great interest. One such component is regional ground-water discharge. Most of the ground water leaving the DVRFS is limited to local areas where geologic and hydrologic conditions force ground water upward toward the surface to discharge at springs and seeps. Available estimates of ground-water discharge are based primarily on early work done as part of regional reconnaissance studies. These early efforts covered large, geologically complex areas and often applied substantially different techniques to estimate ground-water discharge. This report describes the results of a study that provides more consistent, accurate, and scientifically defensible measures of regional ground-water losses from each of the major discharge areas of the DVRFS. Estimates of ground-water discharge presented in this report are based on a rigorous quantification of local evapotranspiration (ET). The study identifies areas of ongoing ground-water ET, delineates different ET areas based on similarities in vegetation and soil-moisture conditions, and determines an ET rate for
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NASA Astrophysics Data System (ADS)
Ma, Bin; Jin, Menggui; Liang, Xing; Li, Jing
2018-02-01
Hydrogeochemistry and environmental tracers (2H, 18O, 87Sr/86Sr) in precipitation, river and reservoir water, and groundwater have been used to determine groundwater recharge sources, and to identify mixing characteristics and mineralization processes in the Manas River Basin (MRB), which is a typical mountain-oasis-desert ecosystem in arid northwest China. The oasis component is artificial (irrigation). Groundwater with enriched stable isotope content originates from local precipitation and surface-water leakage in the piedmont alluvial-oasis plain. Groundwater with more depleted isotopes in the north oasis plain and desert is recharged by lateral flow from the adjacent mountains, for which recharge is associated with high altitude and/or paleo-water infiltrating during a period of much colder climate. Little evaporation and isotope exchange between groundwater and rock and soil minerals occurred in the mountain, piedmont and oasis plain. Groundwater δ2H and δ18O values show more homogeneous values along the groundwater flow direction and with well depths, indicating inter-aquifer mixing processes. A regional contrast of groundwater allows the 87Sr/86Sr ratios and δ18O values to be useful in a combination with Cl, Na, Mg, Ca and Sr concentrations to distinguish the groundwater mixing characteristics. Two main processes are identified: groundwater lateral-flow mixing and river leakage in the piedmont alluvial-oasis plain, and vertical mixing in the north oasis plain and the desert. The 87Sr/86Sr ratios and selected ion ratios reveal that carbonate dissolution and mixing with silicate from the southern mountain area are primarily controlling the strontium isotope hydrogeochemistry.
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Policies, Land Use, and Water Resource Management in an Arid Oasis Ecosystem
NASA Astrophysics Data System (ADS)
Xue, Xian; Liao, Jie; Hsing, Youtian; Huang, Cuihua; Liu, Famin
2015-05-01
This paper addresses two questions concerning the relationship between state policies and environmental transformation in China in the past four decades. The first one deals with the promotion of agricultural productivity since the 1980s; the second, the water conservation measures as a response to the water crisis that peaked in the early 2000s. We had chosen Minqin County in northwestern China, one of the most fragile arid oasis systems in the world, as the study area. We found that the irrigated farmland in up and midstream areas had greatly expanded between the 1980s and the 2000s under the government policy of promoting commodity grain production. As a result, the runoff flowing into Minqin Oasis had reduced 80 % from the 1950s to early 2000s. Irrigated farmland in Minqin Oasis expanded 15.76 % from 1995 to 2000. In the 2000s, because of the changing policy discourse that has shifted from productivity to conservation, a new set of environmentally framed policies has restructured agricultural production in Minqin by 2005. These new policies included establishing a watershed-level water management system, promoting drought resistant crops, introducing water-saving irrigation measures, and forced reduction of irrigated farming acreage. These policies have produced positive results in terms of greater coverage of vegetation, rising ground water table, and reduction of evaporation. Nevertheless, new policies have also brought new challenges to both farmers and policy makers to keep the balance between poverty reduction and environmental sustainability in Minqin Oasis in the historically poor region in China's Northwest.
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Application of the unified mask data format based on OASIS for VSB EB writers
NASA Astrophysics Data System (ADS)
Suzuki, Toshio; Hirumi, Junji; Suga, Osamu
2005-11-01
Mask data preparation (MDP) for modern mask manufacturing becomes a complex process because many kinds of EB data formats are used in mask makers and EB data files continue to become bigger by the application of RET. Therefore we developed a unified mask pattern data format named "OASIS.VSB1" and a job deck format named "MALY2" for Variable-Shaped-Beam (VSB) EB writers. OASIS.VSB is the mask pattern data format based on OASISTM 3 (Open Artwork System Interchange Standard) released as a successive format to GDSII by SEMI. We defined restrictions on OASIS for VSB EB writers to input OASIS.VSB data directly to VSB EB writers just like the native EB data. OASIS.VSB specification and MALY specification have been disclosed to the public and will become a SEMI standard in the near future. We started to promote the spread activities of OASIS.VSB and MALY. For practical use of OASIS.VSB and MALY, we are discussing the infrastructure system of MDP processing using OASIS.VSB and MALY with mask makers, VSB EB makers, and device makers. We are also discussing the tools for the infrastructure system with EDA vendors. The infrastructure system will enable TAT, the man-hour, and the cost in MDP to be reduced. In this paper, we propose the plan of the infrastructure system of MDP processing using OASIS.VSB and MALY as an application of OASIS.VSB and MALY.
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Spatial distribution of an ancient agricultural oasis in Juyan, northwestern China
NASA Astrophysics Data System (ADS)
Hu, Ningke; Li, Xin
2014-09-01
Activities related to agricultural cultivation are some of the major human drivers of landscape change on the Earth's surface. Archaeological remains can provide qualitative evidence for studies of past agricultural development and environmental conditions. The ancient Juyan Oasis, which once flourished along the historic Silk Road, was a typical oasis of downstream inland river basins in the arid zone of northwestern China. Historical records and archaeological discoveries have qualitatively shown that the oasis supported extensive agricultural activities in this historical period from the Han Dynasty to the early Ming Dynasty (B.C. 202-A.D. 1375), which can be traced back to 2,000 years ago. In this study, different types of archaeological remains (including archaeological sites, ground surface artifacts, ancient cultivation ruins, and agricultural irrigation canals) that were obtained and identified from previous archaeological reports, field inspections, and remote sensing imagery were used to determine the spatial extent of the agricultural oasis in the historical period of interest. Our approach used multiple data sources in order to increase the accuracy and reliability of the results compared to previous studies. Our results distinctly suggested that much of the oasis was cultivated during the historical periods considered. Additionally, the arable land area in the historical period considered was roughly estimated to be approximately (3.39-4.75) × 104 ha. These findings regarding the spatial distribution of this ancient agricultural oasis and its arable land were reasonably determined to represent the ancient agricultural development that occurred in the Juyan Oasis better than results obtained from single sources of data.
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The Outcome and Assessment Information Set (OASIS): A Review of Validity and Reliability
O’CONNOR, MELISSA; DAVITT, JOAN K.
2015-01-01
The Outcome and Assessment Information Set (OASIS) is the patient-specific, standardized assessment used in Medicare home health care to plan care, determine reimbursement, and measure quality. Since its inception in 1999, there has been debate over the reliability and validity of the OASIS as a research tool and outcome measure. A systematic literature review of English-language articles identified 12 studies published in the last 10 years examining the validity and reliability of the OASIS. Empirical findings indicate the validity and reliability of the OASIS range from low to moderate but vary depending on the item studied. Limitations in the existing research include: nonrepresentative samples; inconsistencies in methods used, items tested, measurement, and statistical procedures; and the changes to the OASIS itself over time. The inconsistencies suggest that these results are tentative at best; additional research is needed to confirm the value of the OASIS for measuring patient outcomes, research, and quality improvement. PMID:23216513
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Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone
USDA-ARS?s Scientific Manuscript database
Wind erosion in the desert-oasis ecotone can accelerate desertification and thus impacts oasis ecological security. Little is known about the susceptibility of the desert-oasis ecotone to wind erosion in the Tarim Basin even though the ecotone is a major source of windblown dust in China. The object...
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40 CFR 81.55 - Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Northeast Pennsylvania-Upper Delaware... Designation of Air Quality Control Regions § 81.55 Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control Region. The Northeast Pennsylvania-Upper Delaware Valley Interstate Air Quality Control...
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Profile Changes in the Soil Microbial Community When Desert Becomes Oasis
Li, Chen-hua; Tang, Li-song; Jia, Zhong-jun; Li, Yan
2015-01-01
The conversion of virgin desert into oasis farmland creates two contrasting types of land-cover. During oasis formation with irrigation and fertilizer application, however, the changes in the soil microbial population, which play critical roles in the ecosystem, remain poorly understood. We applied high-throughput pyrosequencing to investigate bacterial and archaeal communities throughout the profile (0–3 m) in an experimental field, where irrigation and fertilization began in 1990 and cropped with winter wheat since then. To assess the effects of cultivation, the following treatments were compared with the virgin desert: CK (no fertilizer), PK, NK, NP, NPK, NPKR, and NPKM (R: straw residue; M: manure fertilizer). Irrigation had a greater impact on the overall microbial community than fertilizer application. The greatest impact occurred in topsoil (0–0.2 m), e.g., Cyanobacteria (25% total abundance) were most abundant in desert soil, while Actinobacteria (26%) were most abundant in oasis soil. The proportions of extremophilic and photosynthetic groups (e.g., Deinococcus-Thermus and Cyanobacteria) decreased, while the proportions of R-strategy (e.g., Gammaproteobacteria including Xanthomonadales), nitrifying (e.g., Nitrospirae), and anaerobic bacteria (e.g., Anaerolineae) increased throughout the oasis profile. Archaea occurred only in oasis soil. The impact of fertilizer application was mainly reflected in the non-dominant communities or finer taxonomic divisions. Oasis formation led to a dramatic shift in microbial community and enhanced soil enzyme activities. The rapidly increased soil moisture and decreased salt caused by irrigation were responsible for this shift. Furthermore, difference in fertilization and crop growth altered the organic carbon contents in the soil, which resulted in differences of microbial communities within oasis. PMID:26426279
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The spatio-temporal variability of groundwater depth in a typical desert-oasis ecotone
NASA Astrophysics Data System (ADS)
Wang, Guohua; Zhao, Wenzhi
2015-06-01
Eight groundwater observation wells were installed along the river plain, where the landscapes varied from floodplain, to oasis farmland, to desert-oasis ecotone to desert, in a typical desert-oasis ecotone in northwestern China. Ten years of data were used to analyze temporal and spatial changes in the groundwater depth. The results indicated that in the last decade: (1) the groundwater depths in the floodplain (GW1) and the desert (GW8) were basically stable; (2) the groundwater depths in the oasis farmland (GW2, GW3, GW4) increased dramatically: the annual fluctuations were 1.43, 1.01 and 0.79 m respectively, with the groundwater depths increasing by 0.13-0.18 m every year; (3) the groundwater depths in the desert-oasis ecotone (GW5, GW6, GW7) also increased dramatically: the annual fluctuations were 1.10, 1.06 and 1.05 m respectively, and the depths increased by 0.10-0.15 m every year; (4) the influence distance between the river and both the farmland and the desert-oasis ecotone was about 1000-2000 m in the study area. These results show that the natural seasonal fluctuation influence on groundwater depths was not significant, but the human-induced fluctuations such as intensive irrigation caused a significant increase in groundwater depth in both the farmland and the desert-oasis ecotone, seriously affecting sustainable agriculture development and the environment, in the oasis.
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Modeling the Death Valley regional ground-water flow system
D'Agnese, F. A.; Faunt, C.C.; Hill, M.C.
2004-01-01
The development of a regional ground-water flow model of the Death Valley region in the southwestern United States is discussed in the context of the fourteen guidelines of Hill. This application of the guidelines demonstrates how they may be used for model calibration and evaluation, and to direct further model development and data collection.
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NASA Astrophysics Data System (ADS)
Y Yang, M.; Wang, J.; Zhang, Q.
2017-07-01
Vegetation coverage is one of the most important indicators for ecological environment change, and is also an effective index for the assessment of land degradation and desertification. The dry-hot valley regions have sparse surface vegetation, and the spectral information about the vegetation in such regions usually has a weak representation in remote sensing, so there are considerable limitations for applying the commonly-used vegetation index method to calculate the vegetation coverage in the dry-hot valley regions. Therefore, in this paper, Alternating Angle Minimum (AAM) algorithm of deterministic model is adopted for selective endmember for pixel unmixing of MODIS image in order to extract the vegetation coverage, and accuracy test is carried out by the use of the Landsat TM image over the same period. As shown by the results, in the dry-hot valley regions with sparse vegetation, AAM model has a high unmixing accuracy, and the extracted vegetation coverage is close to the actual situation, so it is promising to apply the AAM model to the extraction of vegetation coverage in the dry-hot valley regions.
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Imaging Radar in the Mojave Desert-Death Valley Region
NASA Technical Reports Server (NTRS)
Farr, Tom G.
2001-01-01
The Mojave Desert-Death Valley region has had a long history as a test bed for remote sensing techniques. Along with visible-near infrared and thermal IR sensors, imaging radars have flown and orbited over the area since the 1970's, yielding new insights into the geologic applications of these technologies. More recently, radar interferometry has been used to derive digital topographic maps of the area, supplementing the USGS 7.5' digital quadrangles currently available for nearly the entire area. As for their shorter-wavelength brethren, imaging radars were tested early in their civilian history in the Mojave Desert-Death Valley region because it contains a variety of surface types in a small area without the confounding effects of vegetation. The earliest imaging radars to be flown over the region included military tests of short-wavelength (3 cm) X-band sensors. Later, the Jet Propulsion Laboratory began its development of imaging radars with an airborne sensor, followed by the Seasat orbital radar in 1978. These systems were L-band (25 cm). Following Seasat, JPL embarked upon a series of Space Shuttle Imaging Radars: SIRA (1981), SIR-B (1984), and SIR-C (1994). The most recent in the series was the most capable radar sensor flown in space and acquired large numbers of data swaths in a variety of test areas around the world. The Mojave Desert-Death Valley region was one of those test areas, and was covered very well with 3 wavelengths, multiple polarizations, and at multiple angles. At the same time, the JPL aircraft radar program continued improving and collecting data over the Mojave Desert Death Valley region. Now called AIRSAR, the system includes 3 bands (P-band, 67 cm; L-band, 25 cm; C-band, 5 cm). Each band can collect all possible polarizations in a mode called polarimetry. In addition, AIRSAR can be operated in the TOPSAR mode wherein 2 antennas collect data interferometrically, yielding a digital elevation model (DEM). Both L-band and C-band can be
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40 CFR 81.90 - Androscoggin Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Quality Control Region. 81.90 Section 81.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.90 Androscoggin Valley Interstate Air Quality Control Region. The...
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40 CFR 81.90 - Androscoggin Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Quality Control Region. 81.90 Section 81.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.90 Androscoggin Valley Interstate Air Quality Control Region. The...
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Histopathological assessment of OASIS Ultra on critical-sized wound healing: a pilot study.
Yeh, Daniel Dante; Nazarian, Rosalynn M; Demetri, Leah; Mesar, Tomaz; Dijkink, Suzan; Larentzakis, Andreas; Velmahos, George; Sadik, Karim Walid
2017-06-01
Dermatopathologists assess wounds secondary to trauma, infection, or oncologic resection that can be challenging to reconstruct. OASIS Ultra, an extracellular matrix, has been described for use in chronic and burn wounds. The aim of this pilot study is to assess wound healing in post-traumatic and infective wounds treated with OASIS using histological markers of repair. Adults with traumatic, infective or iatrogenic wound defects with size precluding primary closure were eligible. Half the wound was randomly assigned to receive OASIS plus standard therapy; the other half received standard of care (SOC) therapy. During dressing changes, standardized-scale photographs were taken and biopsies obtained. Histologic sections were reviewed for degree of acute inflammation and extent of tissue repair. Neutrophils, edema, hemorrhage, necrosis, fibroblasts, collagen density and neovascularization were semi-quantitatively assessed. Forty-four skin biopsies from 7 patients with 10 acute wounds met eligibility criteria. Histologically, OASIS samples demonstrated improved acute inflammation scores compared to SOC. No patients experienced OASIS-related complications. OASIS-treated wound halves trended toward more wound contraction and improved tissue repair. Our scoring system aids histopathological wound assessment. Treatment of critical-sized, post-traumatic, acute wounds with OASIS resulted in decreased inflammation, and potentially more advanced wound healing, compared to SOC. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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An Evaluation of Operational Airspace Sectorization Integrated System (OASIS) Advisory Tool
NASA Technical Reports Server (NTRS)
Lee, Paul U.; Mogford, Richard H.; Bridges, Wayne; Buckley, Nathan; Evans, Mark; Gujral, Vimmy; Lee, Hwasoo; Peknik, Daniel; Preston, William
2013-01-01
In January 2013, a human-in-the-loop evaluation of the Operational Airspace Sectorization Integrated System (OASIS) was conducted in the Airspace Operations Laboratory of the Human Systems Integration Division (Code TH) in conjunction with the Aviation Systems Division (Code AF). The development of OASIS is a major activity of the Dynamic Airspace Configuration (DAC) research focus area within the Aeronautics Research Mission Directorate (ARMD) Airspace Systems Program. OASIS is an advisory tool to assist Federal Aviation Administration (FAA) En Route Area Supervisors in their planning of sector combinedecombine operations as well as opening closing of Data-side (D-side) control positions. These advisory solutions are tailored to the predicted traffic demand over the next few hours. During the experiment, eight retired FAA personnel served as participants for a part-task evaluation of OASIS functionality, covering the user interface as well as the underlying algorithm. Participants gave positive feedback on both the user interface and the algorithm solutions for airspace configuration, including an excellent average rating of 94 on the tool usability scales. They also suggested various enhancements to the OASIS tool, which will be incorporated into the next tool development cycle for the full-scale human-in-the-loop evaluation to be conducted later this year.
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Dependable water supplies from valley alluvium in arid regions.
Van Haveren, Bruce P
2004-12-01
Reliable sources of high-quality water for domestic use are much needed in arid regions. Valley alluvium, coarse sand and gravel deposited by streams and rivers, provides an ideal storage medium for water in many regions of the world. However, river sediments will not accumulate in a valley without a natural or artificial barrier to slow the water. Sediments will deposit upstream of a barrier dam and form an alluvial deposit of relatively well-sorted material. The alluvium then acts as both an underground water-supply reservoir and a water filter, yielding a constant flow of high-quality water. Trap dams that store water in alluvial sediments and slowly release the filtered water represent an appropriate and inexpensive technology for combating desertification and mitigating the effects of drought at the community level. Small trap dams may be built as a community project using local materials and local labor.
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Combining remote sensing image with DEM to identify ancient Minqin Oasis, northwest of China
NASA Astrophysics Data System (ADS)
Xie, Yaowen
2008-10-01
The developing and desertification process of Minqin oasis is representative in the whole arid area of northwest China. Combining Remote Sensing image with Digital Elevation Model (DEM) can produce the three-dimensional image of the research area which can give prominence to the spatial background of historical geography phenomenon's distribution, providing the conditions for extracting and analyzing historical geographical information thoroughly. This research rebuilds the ancient artificial Oasis based on the three-dimensional images produced by the TM digital Remote Sensing image and DEM created using 1:100000 topographic maps. The result indicates that the whole area of the ancient artificial oasis in Minqin Basin over the whole historical period reaches 321km2, in the form of discontinuous sheet, separated on the two banks of ancient Shiyang River and its branches, namely, Xishawo area, west to modern Minqin Basin and Zhongshawo area, in the center of the oasis. Except for a little of the ancient oasis unceasingly used by later people, most of it became desert. The combination of digital Remote Sensing image and DEM can integrate the advantages of both in identifying ancient oasis and improve the interpreting accuracy greatly.
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Liu, Xuelu; Ren, Jizhou; Zhang, Zihe
2002-08-01
Oasis landscape ecosystem is composed of 10 landscape elements, i.e., residence land, cultivated land, grassland, forestland, water area, water system, road, rocky desert, sandy desert, and gravel desert. Among the elements, cultivated land formed by human being production covers the most of the area, is most connected, and hence, is the matrix of the oasis landscape ecosystem. Residence land, grassland, forestland, water area, rocky desert, sandy desert, and gravel desert are patches. Residence land and forestland generate from human being production, while rocky desert, gravel desert and sandy desert are the remnant with the human being disturbance. Water region and grassland are the environmental resources remnant after natural disturbance. Water system and road are corridors. Cultivated land dominated in plant production should be utilized with more productive layers through developing animal production other than expanding used-area to maintain the landscape heterogeneity and diversity of the oasis landscape ecosystem. For remnant and environmental resource patches, it should be profitable in preserving and stabilizing landscape heterogeneity and diversity, exploiting the functions of water and soil conservation, tourism, windbreak and sand fixation. For landscape elements remnant only, it should be fruitful in avoiding degeneration of the landscape pattern to explore their preceding plant production with moderate plant production.
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Ground-water modeling of the Death Valley Region, Nevada and California
Belcher, W.R.; Faunt, C.C.; Sweetkind, D.S.; Blainey, J.B.; San Juan, C. A.; Laczniak, R.J.; Hill, M.C.
2006-01-01
The Death Valley regional ground-water flow system (DVRFS) of southern Nevada and eastern California covers an area of about 100,000 square kilometers and contains very complex geology and hydrology. Using a computer model to represent the complex system, the U.S. Geological Survey simulated ground-water flow in the Death Valley region for use with U.S. Department of Energy projects in southern Nevada. The model was created to help address contaminant cleanup activities associated with the underground nuclear testing conducted from 1951 to 1992 at the Nevada Test Site and to support the licensing process for the proposed geologic repository for high-level nuclear waste at Yucca Mountain, Nevada.
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Erosional valleys in the Thaumasia region of Mars: Hydrothermal and seismic origins
Tanaka, K.L.; Dohm, J.M.; Lias, J.H.; Hare, T.M.
1998-01-01
Analysis of erosional valleys, geologic materials and features, and topography through time in the Thaumasia region of Mars using co-registered digital spatial data sets reveals significant associations that relate to valley origin. Valleys tend to originate (1) on Noachian to Early Hesperian (stages 1 and 2) large volcanoes, (2) within 50-100 km of stages 1 and 2 rift systems, and (3) within 100 km of Noachian (stage 1) impact craters >50 km in diameter. These geologic preferences explain observations of higher valley-source densities (VSDs) in areas of higher elevations and regional slopes (>1??) because the volcanoes, rifts, and craters form high, steep topography or occur in terrain of high relief. Other stage 1 and stage 2 high, steep terrains, however, do not show high VSDs. The tendency for valleys to concentrate near geologic features and the overall low drainage densities in Thaumasia compared to terrestrial surfaces rule out widespread precipitation as a major factor in valley formation (as is proposed in wann, wet climate scenarios) except perhaps during the Early Noachian, for which much of the geologic record has been obliterated. Instead, volcanoes and rifts may indicate the presence of shallow crustal intrusions that could lead to local hydrothermal circulation, melting of ground ice and snow, and groundwater sapping. However, impact-crater melt would provide a heat source at the surface that might drive away water, forming valleys in the process. Post-stage 1 craters mostly have low nearby VSDs, which, for valleys incised in older rocks, suggests burial by e??jecta and, for . younger valleys, may indicate desiccation of near-surface water and deepening of the cryosphere. Later Hesperian and Amazonian (stages 3 and 4) valleys originate within 100-200 km of three young, large impact craters and near rifts systems at Warrego Valle??s and the southern part of Coprates rise. These valleys likely developed when the cryosphere was a couple kilometers or
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Windblown sediment transport and loss in a desert-oasis ecotone in the Tarim Basin.
Pi, Huawei; Sharratt, Brenton; Lei, Jiaqiang
2017-08-10
The Tarim Basin is regarded as one of the most highly erodible areas in China. Desert comprises 64% of the land use in the Basin, but the desert-oasis ecotone plays a prominent role in maintaining oasis ecological security and stability. Yet, little is known concerning the magnitude of windblown sediment transport in a desert-oasis ecotone. Therefore, aeolian sediment transport and loss was assessed from a desert-oasis experimental site located near Alaer City in the northwestern Tarim Basin. Sediment transport and factors governing transport were measured during three high wind events in 2012 and four events in 2013. Sediment transport was measured to a height of 10 m using passive aeolian airborne sediment samplers. The mass flux profile over the eroding surface was well represented by the power-law (R 2 > 0.77). Sediment loss from the site ranged from 118 g m -2 for the 20-24Apr 2012 wind event to 2925 g m -2 for the 31Mar-11Apr 2012 event. Suspension accounted for 67.4 to 84.8% of sediment loss across all high wind events. Our results indicate the severity of wind erosion in a desert-oasis ecotone and thus encourage adoption of management practices that will enhance oasis ecological security.
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NASA Astrophysics Data System (ADS)
Bouaamlat, I.; Larabi, A.; Faouzi, M.
2013-12-01
The geographical location of Tafilalet oasis system (TOS) in the south of the valley of Ziz (Morocco) offers him a particular advantage on the plane of water potential. The surface water which comes from humid regions of the High Atlas and intercepted by a dam then converged through the watercourse of Ziz towards the plain of the TOS, have created the conditions for the formation of a water table relatively rich with regard to the local climatic conditions (arid climate with recurrent drought). Because of this situation, the region has one of the largest palms of North Africa. Thus there is an agricultural activity that is practiced in a 21 irrigation areas whose size rarely exceeds 2,000 hectare. Given the role of the water table in the economic development of the region, a hydrogeological study was conducted to understand the impact of artificial recharge and recurrent droughts on the development of the groundwater reserves of TOS. In this study, a three-dimensional model of groundwater flow was developed for the Tafilalet oasis system aquifer, to assist the decision makers as a "management tool" in order to assess alternative schemes for development and exploitation of groundwater resources based on the variation of artificial recharge and drought, using for the first time the Modflow code. This study takes into account the most possible real hydrogeological conditions and using the geographical information system (GIS) for the organisation and treatment of data and applying a multidisciplinary approach combining geostatistical and hydrogeological modeling. The results from this numerical investigation of the TOS aquifer shows that the commissioning of the dam to control the flows of extreme flood and good management of water releases, has avoided the losses of irrigation water and consequently the non-overexploitation of the groundwater. So that with one or two water releases per year from the dam of flow rate more than 14 million m3/year it is possible to
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40 CFR 81.90 - Androscoggin Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Androscoggin Valley Interstate Air Quality Control Region (Maine-New Hampshire) consists of the territorial... New Hampshire: Cass County. ..., New Sharron Town, New Vineyard Town, Perkins Township, Phillips Town, Salem Township, Strong Town...
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40 CFR 81.90 - Androscoggin Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Androscoggin Valley Interstate Air Quality Control Region (Maine-New Hampshire) consists of the territorial... New Hampshire: Cass County. ..., New Sharron Town, New Vineyard Town, Perkins Township, Phillips Town, Salem Township, Strong Town...
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40 CFR 81.90 - Androscoggin Valley Interstate Air Quality Control Region.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Androscoggin Valley Interstate Air Quality Control Region (Maine-New Hampshire) consists of the territorial... New Hampshire: Cass County. ..., New Sharron Town, New Vineyard Town, Perkins Township, Phillips Town, Salem Township, Strong Town...
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Hanson, R.T.; Li, Zhen; Faunt, C.C.
2004-01-01
The Santa Clara Valley is a long, narrow trough extending about 35 miles southeast from the southern end of San Francisco Bay where the regional alluvial-aquifer system has been a major source of water. Intensive agricultural and urban development throughout the 20th century and related ground-water development resulted in ground-water-level declines of more than 200 feet and land subsidence of as much as 12.7 feet between the early 1900s and the mid-1960s. Since the 1960s, Santa Clara Valley Water District has imported surface water to meet growing demands and reduce dependence on ground-water supplies. This importation of water has resulted in a sustained recovery of the ground-water flow system. To help support effective management of the ground-water resources, a regional ground-water/surface-water flow model was developed. This model simulates the flow of ground water and surface water, changes in ground-water storage, and related effects such as land subsidence. A numerical ground-water/surface-water flow model of the Santa Clara Valley subbasin of the Santa Clara Valley was developed as part of a cooperative investigation with the Santa Clara Valley Water District. The model better defines the geohydrologic framework of the regional flow system and better delineates the supply and demand components that affect the inflows to and outflows from the regional ground-water flow system. Development of the model includes revisions to the previous ground-water flow model that upgraded the temporal and spatial discretization, added source-specific inflows and outflows, simulated additional flow features such as land subsidence and multi-aquifer wellbore flow, and extended the period of simulation through September 1999. The transient-state model was calibrated to historical surface-water and ground-water data for the period 197099 and to historical subsidence for the period 198399. The regional ground-water flow system consists of multiple aquifers that are grouped
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A Total Lightning Climatology for the Tennessee Valley Region
NASA Technical Reports Server (NTRS)
McCaul, E. W.; Goodman, S. J.; Buechler, D. E.; Blakeslee, R.; Christian, H.; Boccippio, D.; Koshak, W.; Bailey, J.; Hallm, J.; Bateman, M.
2003-01-01
Total flash counts derived from the North Alabama Lightning Mapping Array are being processed for 2002 to form a climatology of total lightning for the Tennessee Valley region. The data from this active and interesting period will be compared to data fiom the National Lightning Detection Network, space-based lightning sensors, and weather radars.
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Geophysical Characterization of Groundwater-Fault Dynamics at San Andreas Oasis
NASA Astrophysics Data System (ADS)
Faherty, D.; Polet, J.; Osborn, S. G.
2017-12-01
The San Andreas Oasis has historically provided a reliable source of fresh water near the northeast margin of the Salton Sea, although since the recent completion of the Coachella Canal Lining Project and persistent drought in California, surface water at the site has begun to disappear. This may be an effect of the canal lining, however, the controls on groundwater are complicated by the presence of the Hidden Springs Fault (HSF), a northeast dipping normal fault that trends near the San Andreas Oasis. Its surface expression is apparent as a lineation against which all plant growth terminates, suggesting that it may form a partial barrier to subsurface groundwater flow. Numerous environmental studies have detailed the chemical evolution of waters resources at San Andreas Spring, although there remains a knowledge gap on the HSF and its relation to groundwater at the site. To better constrain flow paths and characterize groundwater-fault interactions, we have employed resistivity surveys near the surface trace of the HSF to generate profiles of lateral and depth-dependent variations in resistivity. The survey design is comprised of lines installed in Wenner Arrays, using an IRIS Syscal Kid, with 24 electrodes, at a maximum electrode spacing of 5 meters. In addition, we have gathered constraints on the geometry of the HSF using a combination of ground-based magnetic and gravity profiles, conducted with a GEM walking Proton Precession magnetometer and a Lacoste & Romberg gravimeter. Seventeen gravity measurements were acquired across the surface trace of the fault. Preliminary resistivity results depict a shallow conductor localized at the oasis and discontinuous across the HSF. Magnetic data reveal a large contrast in subsurface magnetic susceptibility that appears coincident with the surface trace and trend of the HSF, while gravity data suggests a shallow, relatively high density anomaly centered near the oasis. These data also hint at a second, previously
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OASIS: Organics Analyzer for Sampling Icy Surfaces
NASA Technical Reports Server (NTRS)
Getty, S. A.; Dworkin, J. P.; Glavin, D. P.; Martin, M.; Zheng, Y.; Balvin, M.; Southard, A. E.; Ferrance, J.; Malespin, C.
2012-01-01
Liquid chromatography mass spectrometry (LC-MS) is a well established laboratory technique for detecting and analyzing organic molecules. This approach has been especially fruitful in the analysis of nucleobases, amino acids, and establishing chirol ratios [1 -3]. We are developing OASIS, Organics Analyzer for Sampling Icy Surfaces, for future in situ landed missions to astrochemically important icy bodies, such as asteroids, comets, and icy moons. The OASIS design employs a microfabricated, on-chip analytical column to chromatographically separate liquid ana1ytes using known LC stationary phase chemistries. The elution products are then interfaced through electrospray ionization (ESI) and analyzed by a time-of-flight mass spectrometer (TOF-MS). A particular advantage of this design is its suitability for microgravity environments, such as for a primitive small body.
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Miocene rapakivi granites in the southern Death Valley region, California, USA
Calzia, J.P.; Ramo, O.T.
2005-01-01
Rapakivi granites in the southern Death Valley region, California, include the 12.4-Ma granite of Kingston Peak, the ca. 10.6-Ma Little Chief stock, and the 9.8-Ma Shoshone pluton. All of these granitic rocks are texturally zoned from a porphyritic rim facies, characterized by rapakivi textures and miarolitic cavities, to an equigranular aplite core. These granites crystallized from anhydrous and peraluminous to metaluminous magmas that were more oxidized and less alkalic than type rapakivi granites from southern Finland. Chemical and isotope (Nd-Sr-Pb) data suggest that rapakivi granites of the southern Death Valley region were derived by partial melting of lower crustal rocks (possibly including Mesozoic plutonic component) with some mantle input as well; they were emplaced at shallow crustal levels (4 km) in an actively extending orogen.
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Miocene rapakivi granites in the southern Death Valley region, California, USA
Calzia, James P.; Ramo, O.T.
2005-01-01
Rapakivi granites in the southern Death Valley region, California, include the 12.4-Ma granite of Kingston Peak, the ca. 10.6-Ma Little Chief stock, and the 9.8-Ma Shoshone pluton. All of these granitic rocks are texturally zoned from a porphyritic rim facies, characterized by rapakivi textures and miarolitic cavities, to an equigranular aplite core. These granites crystallized from anhydrous and peraluminous to metaluminous magmas that were more oxidized and less alkalic than type rapakivi granites from southern Finland. Chemical and isotope (Nd–Sr–Pb) data suggest that rapakivi granites of the southern Death Valley region were derived by partial melting of lower crustal rocks (possibly including Mesozoic plutonic component) with some mantle input as well; they were emplaced at shallow crustal levels (4 km) in an actively extending orogen.
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An endangered oasis of aquatic microbial biodiversity in the Chihuahuan desert
Souza, Valeria; Espinosa-Asuar, Laura; Escalante, Ana E.; Eguiarte, Luis E.; Farmer, Jack; Forney, Larry; Lloret, Lourdes; Rodríguez-Martínez, Juan M.; Soberón, Xavier; Dirzo, Rodolfo; Elser, James J.
2006-01-01
The Cuatro Cienegas basin in the Chihuahuan desert is a system of springs, streams, and pools. These ecosystems support >70 endemic species and abundant living stromatolites and other microbial communities, representing a desert oasis of high biodiversity. Here, we combine data from molecular microbiology and geology to document the microbial biodiversity of this unique environment. Ten water samples from locations within the Cuatro Cienegas basin and two neighboring valleys as well as three samples of wet sediments were analyzed. The phylogeny of prokaryotic populations in the samples was determined by characterizing cultured organisms and by PCR amplification and sequencing of 16S rRNA genes from total community DNA. The composition of microbial communities was also assessed by determining profiles of terminal restriction site polymorphisms of 16S rRNA genes in total community DNA. There were 250 different phylotypes among the 350 cultivated strains. Ninety-eight partial 16S rRNA gene sequences were obtained and classified. The clones represented 38 unique phylotypes from ten major lineages of Bacteria and one of Archaea. Unexpectedly, 50% of the phylotypes were most closely related to marine taxa, even though these environments have not been in contact with the ocean for tens of millions of years. Furthermore, terminal restriction site polymorphism profiles and geological data suggest that the aquatic ecosystems of Cuatro Cienegas are hydrologically interconnected with adjacent valleys recently targeted for agricultural intensification. The findings underscore the conservation value of desert aquatic ecosystems and the urgent need for study and preservation of freshwater microbial communities. PMID:16618921
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OASIS: PARAMETER ESTIMATION SYSTEM FOR AQUIFER RESTORATION MODELS, USER'S MANUAL VERSION 2.0
OASIS, a decision support system for ground water contaminant modeling, has been developed for the CPA by Rice University, through the National Center for Ground Water Research. As a decision support system, OASIS was designed to provide a set of tools which will help scientists ...
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Fretted Terrain Valley in Coloe Fossae Region
NASA Technical Reports Server (NTRS)
2006-01-01
[figure removed for brevity, see original site] Figure 1 Click on image for larger version The image in figure 1 shows lineated valley fill in one of a series of enclosed, intersecting troughs known as Coloe (Choloe) Fossae. Lineated valley fill consists of rows of material in valley centers that are parallel to the valley walls. It is probably made of ice-rich material and boulders that are left behind when the ice-rich material sublimates. Very distinct rows can be seen near the south (bottom) wall of the valley. Lineated valley fill is thought to result from mass wasting (downslope movement) of ice-rich material from valley walls towards their centers. It is commonly found in valleys near the crustal dichotomy that separates the two hemispheres of Mars. The valley shown here joins four other valleys with lineated fill near the top left corner of this image. Their juncture is a topographic low, suggesting that the lineated valley fill from the different valleys may be flowing or creeping towards the low area (movement towards the upper left of the image). The valley walls appear smooth at first glance but are seen to be speckled with small craters several meters in diameter at HiRISE resolution (see contrast-enhanced subimage). This indicates that at least some of the wall material has been stable to mass wasting for some period of time. Also seen on the valley wall are elongated features shaped like teardrops. These are most likely slightly older craters that have been degraded due to potentially recent downhill creep. It is unknown whether the valley walls are shedding material today. The subimage is approximately 140 x 400 m (450 x 1280 ft). Image PSP_001372_2160 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 11, 2006. The complete image is centered at 35.5 degrees latitude, 56.8 degrees East longitude. The range to the target site was 290.3 km (181 -
Imaging Radar Applications in the Death Valley Region
NASA Technical Reports Server (NTRS)
Farr, Tom G.
1996-01-01
Death Valley has had a long history as a testbed for remote sensing techniques (Gillespie, this conference). Along with visible-near infrared and thermal IR sensors, imaging radars have flown and orbited over the valley since the 1970's, yielding new insights into the geologic applications of that technology. More recently, radar interferometry has been used to derive digital topographic maps of the area, supplementing the USGS 7.5' digital quadrangles currently available for nearly the entire area. As for their shorter-wavelength brethren, imaging radars were tested early in their civilian history in Death Valley because it has a variety of surface types in a small area without the confounding effects of vegetation. In one of the classic references of these early radar studies, in a semi-quantitative way the response of an imaging radar to surface roughness near the radar wavelength, which typically ranges from about 1 cm to 1 m was explained. This laid the groundwork for applications of airborne and spaceborne radars to geologic problems in and regions. Radar's main advantages over other sensors stems from its active nature- supplying its own illumination makes it independent of solar illumination and it can also control the imaging geometry more accurately. Finally, its long wavelength allows it to peer through clouds, eliminating some of the problems of optical sensors, especially in perennially cloudy and polar areas.
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3D Groundwater Flow Model in the Arid Region of Tafilalet Oasis System (South East of Morocco)
NASA Astrophysics Data System (ADS)
Bouaamlat, I.; Larabi, A.; Faouzi, M.
2013-05-01
The plain of Tafilalet contains an important oasis located in the Southeast of Morocco in a pre-Saharan area, characterized by an arid climate with a large deficit water budget. It has a behavior of a large depression resulting from erosion of a set of geological coverage during the Quaternary period. It also forms a small Mesopotamia crossed by two main rivers from the mountains of the High Atlas: Ziz and Rheris. The oasis of Tafilalet is an area of old traditions irrigation where agriculture is the main activity of the region that represents approximately 37% of the total area (637 km2). In this study, a three-dimensional model of groundwater flow was developed for the aquifer system of Tafilalet, to assist the decision makers as a "management tool" in order to assess alternative schemes for development and exploitation of groundwater resources in the Tafilalet plain, using Modflow2000 code. It is the first mathematical model performed for this oasis plain, taking into account the most possible real hydrogeological conditions and using the geographical information system (GIS) for the organisation and treatment of data and applying a multidisciplinary approach combining geostatistical and hydrogeological modeling. The conceptual model, in terms of hydrogeological modeling was therefore considered as a monolayer model and the aquifer system is mainly heterogeneous with lateral different hydraulic conductivities, which are ranging from 3.10-7 to 5.10-2 m/s, but most of them are located between 2.10-4 and 8.10-3 m/s. The results of the model calibration under steady state (1960) and transient state conditions, starting from this time, show reasonable agreement between observed and simulated water levels for the observation wells. After calibration, the model contributed to better groundwater characterization, the hydrodynamic parameters obtained from the model are much representative of reality. As a management tool, this model can help the manager to take
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Late Cenozoic crustal extension and magmatism, southern Death Valley region, California
Calzia, J.P.; Rämö, O.T.
2000-01-01
The late Cenozoic geologic history of the southern Death Valley region is characterized by coeval crustal extension and magamatism. Crustal extension is accommodated by numerous listric and planar normal faults as well as right- and left-lateral strike slip faults. The normal faults sip 30°-50° near the surface and flatten and merge leozoic miogeoclinal rocks; the strike-slip faults act as tear faults between crustal blocks that have extended at different times and at different rates. Crustal extension began 13.4-13.1 Ma and migrated northwestward with time; undeformed basalt flows and lacustrine deposits suggest that extension stopped in this region (but continued north of the Death Valley graben) between 5 and 7 Ma. Estimates of crustal extension in this region vary from 30-50 percent to more than 100 percent. Magmatic rocks syntectonic with crustal extension in the southern Death Valley region include 12.4-6.4 Ma granitic rocks as well as bimodal 14.0-4.0 Ma volcanic rocks. Geochemical and isotopic evidence suggest that the granitic rocks get younger and less alkalic from south to north; the volcanic rocks become more mafic with less evidence of crustal interaction as they get younger. The close spatial and temporal relation between crustal extension and magmatism suggest a genetic and probably a dynamic relation between these geologic processes. We propose a rectonic-magmatic model that requires heat to be transported into the crust by mantle-derived mafic magmas. These magmas pond at lithologic or rheologic boundaries, begin the crystallize, and partially melt the surrounding crustal rocks. With time, the thermally weakened crust is extended (given a regional extensional stress field) concurrent with granitic magmatism and bimodal volcanism.
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Sweetkind, D.S.; Dickerson, R.P.; Blakely, R.J.; Denning, Paul
2001-01-01
This report presents a network of 28 geologic cross sections that portray subsurface geologic relations within the Death Valley regional ground-water system, a ground-water basin that encompasses a 3? x 3? area (approximately 70,000 km2) in southern Nevada and eastern California. The cross sections transect that part of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain. The specific geometric relationships portrayed on the cross sections are discussed in the context of four general sub-regions that have stratigraphic similarities and general consistency of structural style: (1) the Nevada Test Site vicinity; (2) the Spring Mountains, Pahrump Valley and Amargosa Desert region; (3) the Death Valley region; and (4) the area east of the Nevada Test Site. The subsurface geologic interpretations portrayed on the cross sections are based on an integration of existing geologic maps, measured stratigraphic sections, published cross sections, well data, and geophysical data and interpretations. The estimated top of pre-Cenozoic rocks in the cross sections is based on inversion of gravity data, but the deeper parts of the sections are based on geologic conceptual models and are more speculative. The region transected by the cross sections includes part of the southern Basin and Range Province, the northwest-trending Walker Lane belt, the Death Valley region, and the northern Mojave Desert. The region is structurally complex, where a locally thick Tertiary volcanic and sedimentary section unconformably overlies previously deformed Proterozoic through Paleozoic rocks. All of these rocks have been deformed by complex Neogene ex-tensional normal and strike-slip faults. These cross sections form a three-dimensional network that portrays the interpreted stratigraphic and structural relations in the region; the sections form part of the geologic framework that will be
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Geology of the Thaumasia region, Mars: Plateau development, valley origins, and magmatic evolution
Dohm, J.M.; Tanaka, K.L.
1999-01-01
We have constructed the complex geologic history of the Thaumasia region of Mars on the basis of detailed geologic mapping and relative-age dating of rock units and structure. The Thaumasia plateau dominates the region and consists of high lava plains partly surrounded by rugged highlands, mostly of Noachian and Hesperian age. Long-lived faulting centered near Syria Planum and at lesser sites produced radiating narrow grabens during the Noachian through Early Amazonian and concentric wrinkle ridges during the Late Noachian and Early Hesperian. Fault activity peaked during the Noachian and waned substantially during Late Hesperian and Amazonian time. Volcanism on the Thaumasia plateau was particularly active in comparison with other martian cratered highlands, resulting in fourteen volcanoes and numerous outcrops of smooth, ridged, and lobate plains materials. A particularly extensive set of overlapping lava-flow units was emplaced sequentially from Thaumasia Planum to Syria Planum, spanning from the Late Noachian to the Late Hesperian; lobate flows succeeded smooth flow at the beginning of the Late Hesperian. Deep crustal intrusion and a thickened, buoyant crust may have caused the uplift of the plateau during the Noachian and Early Hesperian, resulting in outward-verging fold-and-thrust plateau margins. This structural style appears similar to that of the young ranges of the Rocky Mountains in the western U.S. Within the plateau, several sites of volcanotectonic activity and valley erosion may be underlain by large and perhaps long-lived magmatic intrusions. One such site occurs at the headland of Warrego Valles. Here, at least two episodes of valley dissection from the Noachian to Early Hesperian occurred during the formation of two nearby rift systems. The site also is a locus of intersection for regional narrow grabens during the Late Noachian and Early Hesperian. However, at the site, such faults diverge or terminate, which suggests that a resistant body of
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40 CFR 81.239 - Upper Rio Grande Valley Intrastate Air Quality Control Region.
Code of Federal Regulations, 2011 CFR
2011-07-01
.... The Upper Rio Grande Valley Intrastate Air Quality Control Region (New Mexico) consists of the... Quality Control Region. 81.239 Section 81.239 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...
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40 CFR 81.239 - Upper Rio Grande Valley Intrastate Air Quality Control Region.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... The Upper Rio Grande Valley Intrastate Air Quality Control Region (New Mexico) consists of the... Quality Control Region. 81.239 Section 81.239 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of...
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Wang, Shuixian; Wu, Bin; Yang, Pengnian
2014-12-01
The Yanqi Basin, one of the most productive agricultural areas, has a high population density in Xinjiang, Northwest China. Land use changes, mainly driven by oasis expansion, significantly impact ecosystem services and functions, but these effects are difficult to quantify. The valuation of ecosystem services is important to clarify the ecological and environmental changes caused by agriculturalization of oasis. This study aimed to investigate variations in ecosystem services in response to land use changes during oasis agricultural expansion activities in the Yanqi Basin from 1964 to 2009. The methods used were based on formula of ecosystem service value (ESV) and ESV coefficients. Satellite data were combined with the ESV coefficients to quantify land use changes and ecosystem service changes in the study area. Sensitivity analysis determined the effect of manipulating the coefficients on the estimated values. The results show that the total ESVs in the Yanqi Basin were $1,674, $1,692, $1,471, $1,732, and $1,603 million in 1964, 1973, 1989, 1999, and 2009, respectively. The net deline in ESV was $71 million in the past 46 years, but the ESVs of each types of landscape changed significantly. The aggregated ESVs of water areas and wetlands were approximately 80 % of the total ESV. Water supply and waste treatment were the two largest service functions and contributed approximately 65 % of the total ESV. The estimated ESVs in this study were elastic with respect to the value coefficients. Therefore, the estimations were robust in spite of uncertainties on the value coefficients. These significant changes in land use occur within the entire basin over the study period. These changes cause environmental problems, such as land degradation, vegetation degeneracy, and changes in aquatic environment.
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STS-26 Discovery, OV-103, OASIS equipment is mounted in payload bay (PLB)
1988-04-18
S88-37764 (18 April 1988) --- OASIS, instrumentation which will record the environment experienced by Discovery during the STS-26 Space Shuttle mission, is lowered into position for attachment to the orbiter's aft port sill. Instrumentation sensors in the payload bay which are connected to the tape recorder module will document a variety of environmental measurements during various phases of the flight including temperature, pressure, vibration, sounds, acceleration, stress, and strain. OASIS will also record data during the Flight Readiness Firing. NASA is flying OASIS aboard Discovery in support of the Inertial Upper Stage (IUS) program office of the Air Force Space Division. The system was developed by Lockheed under a NASA contract, funded by the Air Force.
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NASA Astrophysics Data System (ADS)
Kress, A.; Head, J. W.
2009-03-01
Studies of lineated valley fill and lobate debris aprons in the Deuteronilus Mensae region, Mars, reveal that they are endmembers of a continuum of morphologies with the same mode of origin, which is that of debris-covered glacier.
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Imperial Contradictions: Is the Valley a Watershed, Region, or Cyborg?
ERIC Educational Resources Information Center
Rudy, Alan P.
2005-01-01
Is California's Imperial Valley a watershed? If so, at what level and by what topographic logic? Is it a region? If so, at what level and by what geographic logic? Are its boundaries natural, political, or multivalent on different scales? In short, this essay looks at the special (re)production of environmental conditions within a cyborg world.…
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Choi, Jeungok; Jenkins, Melinda L.; Cimino, James J.; White, Thomas M.; Bakken, Suzanne
2005-01-01
Objective: The authors aimed to (1) formally represent OASIS-B1 concepts using the Logical Observation Identifiers, Names, and Codes (LOINC) semantic structure; (2) demonstrate integration of OASIS-B1 concepts into a concept-oriented terminology, the Medical Entities Dictionary (MED); (3) examine potential hierarchical structures within LOINC among OASIS-B1 and other nursing terms; and (4) illustrate a Web-based implementation for OASIS-B1 data entry using Dialogix, a software tool with a set of functions that supports complex data entry. Design and Measurements: Two hundred nine OASIS-B1 items were dissected into the six elements of the LOINC semantic structure and then integrated into the MED hierarchy. Each OASIS-B1 term was matched to LOINC-coded nursing terms, Home Health Care Classification, the Omaha System, and the Sign and Symptom Check-List for Persons with HIV, and the extent of the match was judged based on a scale of 0 (no match) to 4 (exact match). OASIS-B1 terms were implemented as a Web-based survey using Dialogix. Results: Of 209 terms, 204 were successfully dissected into the elements of the LOINC semantics structure and integrated into the MED with minor revisions of MED semantics. One hundred fifty-one OASIS-B1 terms were mapped to one or more of the LOINC-coded nursing terms. Conclusion: The LOINC semantic structure offers a standard way to add home health care data to a comprehensive patient record to facilitate data sharing for monitoring outcomes across sites and to further terminology management, decision support, and accurate information retrieval for evidence-based practice. The cross-mapping results support the possibility of a hierarchical structure of the OASIS-B1 concepts within nursing terminologies in the LOINC database. PMID:15802480
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Choi, Jeungok; Jenkins, Melinda L; Cimino, James J; White, Thomas M; Bakken, Suzanne
2005-01-01
The authors aimed to (1) formally represent OASIS-B1 concepts using the Logical Observation Identifiers, Names, and Codes (LOINC) semantic structure; (2) demonstrate integration of OASIS-B1 concepts into a concept-oriented terminology, the Medical Entities Dictionary (MED); (3) examine potential hierarchical structures within LOINC among OASIS-B1 and other nursing terms; and (4) illustrate a Web-based implementation for OASIS-B1 data entry using Dialogix, a software tool with a set of functions that supports complex data entry. Two hundred nine OASIS-B1 items were dissected into the six elements of the LOINC semantic structure and then integrated into the MED hierarchy. Each OASIS-B1 term was matched to LOINC-coded nursing terms, Home Health Care Classification, the Omaha System, and the Sign and Symptom Check-List for Persons with HIV, and the extent of the match was judged based on a scale of 0 (no match) to 4 (exact match). OASIS-B1 terms were implemented as a Web-based survey using Dialogix. Of 209 terms, 204 were successfully dissected into the elements of the LOINC semantics structure and integrated into the MED with minor revisions of MED semantics. One hundred fifty-one OASIS-B1 terms were mapped to one or more of the LOINC-coded nursing terms. The LOINC semantic structure offers a standard way to add home health care data to a comprehensive patient record to facilitate data sharing for monitoring outcomes across sites and to further terminology management, decision support, and accurate information retrieval for evidence-based practice. The cross-mapping results support the possibility of a hierarchical structure of the OASIS-B1 concepts within nursing terminologies in the LOINC database.
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Narrating Regional Identity in Tourism--Sketches from the Austrian Danube Valley
ERIC Educational Resources Information Center
Ploner, Josef
2009-01-01
This article sketches the processes of regionalisation in the realm of present day tourism. By exploring issues of "regional culture" and "diversity" in Austria, and more particular, in the highly symbolic Danube valley "Wachau", the article shows how the imaginaries of contested cultural spaces--be they…
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Windblown sediment transport and loss in a desert–oasis ecotone in the Tarim Basin
USDA-ARS?s Scientific Manuscript database
The Tarim Basin is regarded as one of the most highly erodible areas in China. Desert comprises 64% of the land use in the Basin, but the desert–oasis ecotone plays a prominent role in maintaining oasis ecological security and stability. Yet, little is known concerning the magnitude of windblown sed...
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42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... operating the OASIS system: (a) Establish and maintain an OASIS database. The State agency or other entity designated by CMS must— (1) Use a standard system developed or approved by CMS to collect, store, and analyze..., system back-up, and monitoring the status of the database; and (3) Obtain CMS approval before modifying...
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Zhang, Fei; Tiyip, Tashpolat; Ding, Jianli; Sawut, Mamat; Tashpolat, Nigara; Kung, Hsiangte; Han, Guihong; Gui, Dongwei
2012-08-01
Aiming at the remote sensing application has been increasingly relying on ground object spectral characteristics. In order to further research the spectral reflectance characteristics in arid area, this study was performed in the typical delta oasis of Weigan and Kuqa rivers located north of Tarim Basin. Data were collected from geo-targets at multiple sites in various field conditions. The spectra data were collected for different soil types including saline-alkaline soil, silt sandy soil, cotton field, and others; vegetations of Alhagi sparsifolia, Phragmites australis, Tamarix, Halostachys caspica, etc., and water bodies. Next, the data were processed to remove high-frequency noise, and the spectral curves were smoothed with the moving average method. The derivative spectrum was generated after eliminating environmental background noise so that to distinguish the original overlap spectra. After continuum removal of the undesirable absorbance, the spectrum curves were able to highlight features for both optical absorbance and reflectance. The spectrum information of each ground object is essential for fully utilizing the multispectrum data generated by remote sensing, which will need a representative spectral library. In this study using ENVI 4.5 software, a preliminary spectral library of surface features was constructed using the data surveyed in the study area. This library can support remote sensing activities such as feature investigation, vegetation classification, and environmental monitoring in the delta oasis region. Future plan will focus on sharing and standardizing the criteria of professional spectral library and to expand and promote the utilization of the spectral databases.
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The Skateboard Factory: Curriculum by Design--Oasis Skateboard Factory Q&A with Craig Morrison
ERIC Educational Resources Information Center
Pearson, George
2012-01-01
Since its opening three years ago, Oasis Skateboard Factory (OSF), founded by teacher Craig Morrison, has attracted considerable media exposure and received a Ken Spencer Award from the CEA for its innovative program. OSF is one of three programs offered by Oasis Alternative Secondary School, one of 22 alternative secondary schools of the Toronto…
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Oasis Connections: Results from an Evaluation Study
ERIC Educational Resources Information Center
Czaja, Sara J.; Lee, Chin Chin; Branham, Janice; Remis, Peggy
2012-01-01
Purpose of the Study: The objectives of this study were to evaluate a community-based basic computer and Internet training program designed for older adults, provide recommendations for program refinement, and gather preliminary information on program sustainability. Design and Methods: The program was developed by the OASIS Institute, a nonprofit…
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NASA Technical Reports Server (NTRS)
Haldemann, A. F. C.; Kleindienst, M. R.; Churcher, C. S.; Smith, J. R.; Schwarcz, H. P.; Osinski, G.
2005-01-01
Over the past decade members of the Dakhleh Oasis Project have studied enigmatic signatures in the Pleistocene geologic record of portions of the Dakhleh oasis and palaeo-oasis in Egypt's Western Desert [1,2]. In particular, Si-Ca-Al rich glass melt (Dakhleh Glass, Fig. 1) points to a catastrophic event between c.100,000-200,000 years ago [3] in this well-studied African savannah and freshwater lake Middle Stone Age environment [4,5].
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Mohiudin, Henna; Ali, Sajjad; Pisal, Pradyna N; Villar, Rose
2018-05-01
To audit the impact of implementation of the RCOG guidelines for prevention of Obstetric anal sphincter injuries (OASIS) by introducing antenatal perineal massage, manual perineal protection, and cutting episiotomies at 60° to the midline at the time of crowning. Time series analysis; Setting - Two London teaching hospitals; Royal Free London (RFL) and Barnet; Population or Sample - All nulliparous women undergoing vaginal birth; Methods - Training was provided for above techniques. EPISCISSORS-60 were introduced to perform 60° episiotomies. Data were extracted from maternity databases and dashboards; Main Outcome Measures - OASIS rates before and after implementation. Data from 2566 births were analysed. In operative vaginal deliveries (OVD), OASIS declined from 9.6% to 2% (p = 0.001) at Barnet and from 5.6% to 4.2% (p = 0.4) at RFL. OASIS reduced in nulliparous OVD's given episiotomies from 6.3% in the 'before' period to 0.6% in the 'after' period [p = 0.01] at Barnet. Before introduction of the EPISCISSORS-60, OASIS rate was 6.3% with episiotomies and 30% without episiotomies (p = 0.000). After introduction of the EPISCISSORS-60, OASIS rate was 0.63% with episiotomies v 16% without episiotomies (p = 0.000) at Barnet. At RFL, OASIS rate was 2.6% with episiotomies, and 42% without episiotomy (p = 0.000). In SVD's at Barnet, OASIS declined from 6.6% before to 0% after (p = 0.000) in women given episiotomies while it declined from 5.4% to 3% (p = 0.12) in those not given episiotomies. After introduction of the EPISCISSORS-60, OASIS was 0% in women with episiotomies and 3% in those without episiotomies (p = 0.04). In SVD's at RFL, OASIS was 0% in women given episiotomy v 4.7% without episiotomy (p = 0.03). Deliveries with EPISCISSORS-60 episiotomies had lesser OASIS than those without episiotomies in both nulliparous OVD's and SVD's. OASIS was lower with EPISCISSORS-60 episiotomies than those with eyeballed episiotomies
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NASA Astrophysics Data System (ADS)
Bouzekraoui, Hicham; Barakat, Ahmed; El Youssi, Mohammed; El Khalki, Yahia; Hafid, Abdelatif; Mouaddine, Atika
2016-04-01
Central High-Atlas mountain in the centre of Morocco, contains an exceptional geodiversity. Some geomorphological and geological objects of it are included and protected recently by the World Heritage list. The valley of Aït Bou Oulli is located in the heart of the Moroccan central High-Atlas, whose height is 4068 m in Ighil M'goun and 3800 m in Rat Mountain. The mountain areas are characterized by higher geodiversity in comparison with other areas. The valley possesses a geological and geomorphological heritage which is very rich, much diversified and exceptional landscapes of high mountains. It is part of geopark M'Goun; the valley attracts a number of tourists every year. However, this number remains restricted because of the lack of the tools of promotion, valuation and mediation of this geoheritage. Moreover, the touristic infrastructure is modest. Regarding this situation, the geotouristic map appears as a tool of promotion of the geotourism and diversification of the regional and national tourist product. This work aims at elaborating new maps of geomorphosites, cultural sites, and geomonuments in high Mountain landscapes of the valley, suggested in geotourism circuits. The first results reveal the low exploitation of the geodiversity of this valley-oasis: the spectacular waterfalls, water sources, canyons, glacial cirques and U-shaped valleys, superficial karstic forms (sinkholes and swallow-holes), high-Atlas peaks and cliffs, spectacular scree slopes, badlands landscapes, fairy chimneys, and the geological history dating back to the Paleozoic and angular unconformity. In addition, the valley has diverse tangible cultural heritage spanning hundreds of years such as the enigmatic rock engravings (dating from 2000 to 3000 years), troglodyte caves and terraced agriculture landscapes, geomonuments (old cooperative storage, Kasbah, traditional water mills) and the architecture of the villages. It has also an intangible cultural heritage such as folklore. This
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Sweeney, Elizabeth M; Shinohara, Russell T; Shiee, Navid; Mateen, Farrah J; Chudgar, Avni A; Cuzzocreo, Jennifer L; Calabresi, Peter A; Pham, Dzung L; Reich, Daniel S; Crainiceanu, Ciprian M
2013-01-01
Magnetic resonance imaging (MRI) can be used to detect lesions in the brains of multiple sclerosis (MS) patients and is essential for diagnosing the disease and monitoring its progression. In practice, lesion load is often quantified by either manual or semi-automated segmentation of MRI, which is time-consuming, costly, and associated with large inter- and intra-observer variability. We propose OASIS is Automated Statistical Inference for Segmentation (OASIS), an automated statistical method for segmenting MS lesions in MRI studies. We use logistic regression models incorporating multiple MRI modalities to estimate voxel-level probabilities of lesion presence. Intensity-normalized T1-weighted, T2-weighted, fluid-attenuated inversion recovery and proton density volumes from 131 MRI studies (98 MS subjects, 33 healthy subjects) with manual lesion segmentations were used to train and validate our model. Within this set, OASIS detected lesions with a partial area under the receiver operating characteristic curve for clinically relevant false positive rates of 1% and below of 0.59% (95% CI; [0.50%, 0.67%]) at the voxel level. An experienced MS neuroradiologist compared these segmentations to those produced by LesionTOADS, an image segmentation software that provides segmentation of both lesions and normal brain structures. For lesions, OASIS out-performed LesionTOADS in 74% (95% CI: [65%, 82%]) of cases for the 98 MS subjects. To further validate the method, we applied OASIS to 169 MRI studies acquired at a separate center. The neuroradiologist again compared the OASIS segmentations to those from LesionTOADS. For lesions, OASIS ranked higher than LesionTOADS in 77% (95% CI: [71%, 83%]) of cases. For a randomly selected subset of 50 of these studies, one additional radiologist and one neurologist also scored the images. Within this set, the neuroradiologist ranked OASIS higher than LesionTOADS in 76% (95% CI: [64%, 88%]) of cases, the neurologist 66% (95% CI: [52%, 78
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Oasis: A high-level/high-performance open source Navier-Stokes solver
NASA Astrophysics Data System (ADS)
Mortensen, Mikael; Valen-Sendstad, Kristian
2015-03-01
Oasis is a high-level/high-performance finite element Navier-Stokes solver written from scratch in Python using building blocks from the FEniCS project (fenicsproject.org). The solver is unstructured and targets large-scale applications in complex geometries on massively parallel clusters. Oasis utilizes MPI and interfaces, through FEniCS, to the linear algebra backend PETSc. Oasis advocates a high-level, programmable user interface through the creation of highly flexible Python modules for new problems. Through the high-level Python interface the user is placed in complete control of every aspect of the solver. A version of the solver, that is using piecewise linear elements for both velocity and pressure, is shown to reproduce very well the classical, spectral, turbulent channel simulations of Moser et al. (1999). The computational speed is strongly dominated by the iterative solvers provided by the linear algebra backend, which is arguably the best performance any similar implicit solver using PETSc may hope for. Higher order accuracy is also demonstrated and new solvers may be easily added within the same framework.
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Plant diversity and conservation status of Himalayan Region Poonch Valley Azad Kashmir (Pakistan).
Khan, Muhammad Azam; Khan, Mir Ajab; Hussain, Mazhar; Mujtaba, Ghulam
2014-09-01
The plant diversity of Himalayan region has been reduced to greater extent due to environmental degradation and human exploitation. Anthropogenic disturbance was the major factor responsible for fragmentation of forest vegetation into small patches. Little research has been conducted in the Himalayan region of Poonch Valley of North eastern Pakistan with reference to plants biodiversity and its conservation. The present research was carried out to provide a checklist of vegetation for biodiversity conservation. A total of 430 vascular and 5 nonvascular plant species with 5 species of Bryophytes (5 families), 13 species of Pteridophytes (6 families), 4 species of Gymnosperms (1 family) and 413 species of angiosperms (95 families) were enumerated from the Poonch valley Azad Kashmir. The genera were classified into three categories according to the number of species. 25 plant communities with phytosociological parameters and diversity indices were reported. Present study revealed that there were 145 threatened, 30 endangered, 68 vulnerable and 47 rare species. It is recorded that extensive grazing, uprooting of plants and soil slope erosion intensify the environmental problems. Since there is maximum exploitation of vegetation, the valley showed a decline in plant diversity. The study was also indicated that the main threats to the biodiversity are expansion of settlement and army installations in the forest area of the valley. For sustainable use In-situ and Ex-situ conservation, controlled harvesting and afforestation may be the solution. Moreover, forest area should be declared prohibited for settlements and army installations.
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Han, Seong Kyu; Lee, Dongyeop; Lee, Heetak; Kim, Donghyo; Son, Heehwa G; Yang, Jae-Seong; Lee, Seung-Jae V; Kim, Sanguk
2016-08-30
Online application for survival analysis (OASIS) has served as a popular and convenient platform for the statistical analysis of various survival data, particularly in the field of aging research. With the recent advances in the fields of aging research that deal with complex survival data, we noticed a need for updates to the current version of OASIS. Here, we report OASIS 2 (http://sbi.postech.ac.kr/oasis2), which provides extended statistical tools for survival data and an enhanced user interface. In particular, OASIS 2 enables the statistical comparison of maximal lifespans, which is potentially useful for determining key factors that limit the lifespan of a population. Furthermore, OASIS 2 provides statistical and graphical tools that compare values in different conditions and times. That feature is useful for comparing age-associated changes in physiological activities, which can be used as indicators of "healthspan." We believe that OASIS 2 will serve as a standard platform for survival analysis with advanced and user-friendly statistical tools for experimental biologists in the field of aging research.
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Zhang, Peng Peng; Liu, Yan Jie; Pu, Xiao Zhen; Zhang, Guo Juan; Wang, Jin; Zhang, Wang Feng
2016-11-18
To reveal the regulation mechanisms of agricultural management practices on soil organic carbon (SOC) pools and provide scientific basis for improving soil productivity and formulating agricultural fixed carbon and reducing discharge measures, we monitored the changes of SOC pools and organic carbon fractions in an oasis cotton field under different residue management and fertilizer application modes. A split-plot experimental design was used with differing residue management including residue incorporation (S) and residue removing (NS) in the main plots and differing fertilizer application modes including no fertilizer (CK), NPK fertilizer (NPK), organic manure (OM) and NPK fertilizer plus organic manure (NPK+OM) in the subplot. The results showed that fertilization and residue incorporation significantly increased SOC pool, soil organic carbon (C T ), labile carbon (C L ), microbial biomass carbon (C MB ), water-soluble organic carbon (C WS ), hot-water-soluble organic carbon (C HWS ), accumulative amount of soil organic carbon mineralization (C TM ) and carbon management index (CMI). The SOC pool was increased by 20.6% by residue incorporation compared to residue removing. SOC pools were increased by 7.8%, 29.5% and 37.7% in NPK, OM and NPK+OM treatments compared to CK, respectively. The contents of C T , C L , C MB , C WS and C HWS under different fertilization treatments were shown as NPK+OM>OM>NPK>CK. C TM was increased by 5.9% by residue incorporation compared to residue removing and C TM was increased by 32.7%, 59.5% and 97.3% in NPK, OM and NPK+OM treatments compared to CK, respectively. There was a significant correlation between CMI and C T , C MB , C L , C WS , C HWS , C TM , C pool and C sequestration. Therefore, we concluded that CMI is an important index for evaluating the effect of agricultural management practices on soil quality. In order to construct high-standard oasis farmland in arid region and develop cotton production, we should consider
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Validation of SWEEP for creep, saltation, and suspension in a desert-oasis ecotone
NASA Astrophysics Data System (ADS)
Pi, H.; Sharratt, B.; Feng, G.; Lei, J.; Li, X.; Zheng, Z.
2016-03-01
Wind erosion in the desert-oasis ecotone can accelerate desertification, but little is known about the susceptibility of the ecotone to wind erosion in the Tarim Basin despite being a major source of windblown dust in China. The objective of this study was to test the performance of the Single-event Wind Erosion Evaluation Program (SWEEP) in simulating soil loss as creep, saltation, and suspension in a desert-oasis ecotone. Creep, saltation, and suspension were measured and simulated in a desert-oasis ecotone of the Tarim Basin during discrete periods of high winds in spring 2012 and 2013. The model appeared to adequately simulate total soil loss (ranged from 23 to 2272 g m-2 across sample periods) according to the high index of agreement (d = 0.76). The adequate agreement of the SWEEP in simulating total soil loss was due to the good performance of the model (d = 0.71) in simulating creep plus saltation. The SWEEP model, however, inadequately simulated suspension based upon a low d (⩽0.43). The slope estimates of the regression between simulated and measured suspension and difference of mean suggested that the SWEEP underestimated suspension. The adequate simulation of creep plus saltation thus provides reasonable estimates of total soil loss using SWEEP in a desert-oasis environment.
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NASA Astrophysics Data System (ADS)
Song, W. J.; Chen, M. H.; Zhang, Q.; Liu, S. S.; Yang, J. N.
2017-07-01
Oases in arid areas are environmentally and economically vulnerable regions. Study on ecological security of oases in arid areas is of great significance to the stability and the economic development of oases. Based on Land Use/Land Cover data in 1965, 1980, 1995, 2005 and 2015, the study analyze the temporal and spatial changes in human disturbance and ecological security of oases in the Northern Tianshan Mountain Slope Economic Zone (NTMSEZ) in recent 50 years by establishing the ecological security index (ESI) through human disturbance index and landscape vulnerability index. The results showed that: in recent 50 years, the human disturbance of the NTMSEZ has been increased to current moderate human impacts. Urban construction, oasis expansion and farmland reclamation are the main factors of the increment. The human disturbance in Urumchi, Shihezi, Kuitun, Miquan and Changji is higher than that in other oases and that in core areas of oasis is higher than other areas. The ESI of the NTMSEZ increases firstly and then decreases. In most areas, the ESI is “relatively unsafe” and “critical”. However, there are increasingly more vulnerable areas, moving northwestwards and expanding southwards. The ESI gradually presents a “NW-SE” trend of zonal distribution pattern.
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Oasis in Iraq: Universities Flourish in Kurdistan
ERIC Educational Resources Information Center
Krieger, Zvika
2007-01-01
The campus of Salahadin University--peaceful, bustling, and collegial-- is a rare sight in Iraq, where sectarian violence has brought the higher education system to the verge of collapse. Home to the country's historically repressed four million to five million ethnic Kurds, it is an oasis of stability and tranquility while much of the rest of…
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NASA Astrophysics Data System (ADS)
Amuti, T.; Luo, G.
2014-07-01
The combined effects of drought, warming and the changes in land cover have caused severe land degradation for several decades in the extremely arid desert oases of Southern Xinjiang, Northwest China. This study examined land cover changes during 1990-2008 to characterize and quantify the transformations in the typical oasis of Hotan. Land cover classifications of these images were performed based on the supervised classification scheme integrated with conventional vegetation and soil indexes. Change-detection techniques in remote sensing (RS) and a geographic information system (GIS) were applied to quantify temporal and spatial dynamics of land cover changes. The overall accuracies, Kappa coefficients, and average annual increase rate or decrease rate of land cover classes were calculated to assess classification results and changing rate of land cover. The analysis revealed that major trends of the land cover changes were the notable growth of the oasis and the reduction of the desert-oasis ecotone, which led to accelerated soil salinization and plant deterioration within the oasis. These changes were mainly attributed to the intensified human activities. The results indicated that the newly created agricultural land along the margins of the Hotan oasis could result in more potential areas of land degradation. If no effective measures are taken against the deterioration of the oasis environment, soil erosion caused by land cover change may proceed. The trend of desert moving further inward and the shrinking of the ecotone may lead to potential risks to the eco-environment of the Hotan oasis over the next decades.
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Regional dust storm modeling for health services: The case of valley fever
NASA Astrophysics Data System (ADS)
Sprigg, William A.; Nickovic, Slobodan; Galgiani, John N.; Pejanovic, Goran; Petkovic, Slavko; Vujadinovic, Mirjam; Vukovic, Ana; Dacic, Milan; DiBiase, Scott; Prasad, Anup; El-Askary, Hesham
2014-09-01
On 5 July 2011, a massive dust storm struck Phoenix, Arizona (USA), raising concerns for increased cases of valley fever (coccidioidomycosis, or, cocci). A quasi-operational experimental airborne dust forecast system predicted the event and provides model output for continuing analysis in collaboration with public health and air quality communities. An objective of this collaboration was to see if a signal in cases of valley fever in the region could be detected and traced to the storm - an American haboob. To better understand the atmospheric life cycle of cocci spores, the DREAM dust model (also herein, NMME-DREAM) was modified to simulate spore emission, transport and deposition. Inexact knowledge of where cocci-causing fungus grows, the low resolution of cocci surveillance and an overall active period for significant dust events complicate analysis of the effect of the 5 July 2011 storm. In the larger context of monthly to annual disease surveillance, valley fever statistics, when compared against PM10 observation networks and modeled airborne dust concentrations, may reveal a likely cause and effect. Details provided by models and satellites fill time and space voids in conventional approaches to air quality and disease surveillance, leading to land-atmosphere modeling and remote sensing that clearly mark a path to advance valley fever epidemiology, surveillance and risk avoidance.
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Landslide susceptibility in the Tully Valley area, Finger Lakes region, New York
Jager, Stefan; Wieczorek, Gerald E.
1994-01-01
As a consequence of a large landslide in the Tully Valley, Onondaga County, New York, an investigation was undertaken to determine the factors responsible for the landslide in order to develop a model for regional landslide susceptibility. The April 27, 1993 Tully Valley landslide occurred within glacial lake clays overlain by till and colluvium on gentle slopes of 9-12 degrees. The landslide was triggered by extreme climatic events of prolonged heavy rainfall combined with rapid melting of a winter snowpack. A photoinventory and field checking of landslides within a 415 km2 study area, including the Tully Valley, revealed small recently-active landslides and other large dormant prehistoric landslides, probably Pleistocene in age. Similar to the larger Tully Valley landslide, the smaller recently-active landslides occurred in red, glacial lake clays very likely triggered by seasonal rainfall. The large dormant landslides have been stable for long periods as evidenced by slope denudational processes that have modified the landslides. These old and ancient landslides correspond with proglacial lake levels during the Pleistocene, suggesting that either inundation or rapid drainage was responsible for triggering these landslides. A logistic regression analysis was performed within a Geographic Information System (GIS) environment to develop a model of landslide susceptibility for the Tully Valley study area. Presence of glacial clays, slope angle, and glacial lake levels were used as explanatory variables for landslide incidence. The spatial probability of landsliding, categorized as low, moderate and high, is portrayed within 90-m square cells on the susceptibility map.
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18 CFR 37.8 - Obligations of OASIS users.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME INFORMATION SYSTEMS § 37.8... initiating a significant amount of automated queries. The OASIS user must also notify the Responsible Party one month in advance of expected significant increases in the volume of automated queries. [Order 605...
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Chen, Ting; Rangarajan, Anand; Vemuri, Baba C.
2010-01-01
This paper presents a novel classification via aggregated regression algorithm – dubbed CAVIAR – and its application to the OASIS MRI brain image database. The CAVIAR algorithm simultaneously combines a set of weak learners based on the assumption that the weight combination for the final strong hypothesis in CAVIAR depends on both the weak learners and the training data. A regularization scheme using the nearest neighbor method is imposed in the testing stage to avoid overfitting. A closed form solution to the cost function is derived for this algorithm. We use a novel feature – the histogram of the deformation field between the MRI brain scan and the atlas which captures the structural changes in the scan with respect to the atlas brain – and this allows us to automatically discriminate between various classes within OASIS [1] using CAVIAR. We empirically show that CAVIAR significantly increases the performance of the weak classifiers by showcasing the performance of our technique on OASIS. PMID:21151847
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Chen, Ting; Rangarajan, Anand; Vemuri, Baba C
2010-04-14
This paper presents a novel classification via aggregated regression algorithm - dubbed CAVIAR - and its application to the OASIS MRI brain image database. The CAVIAR algorithm simultaneously combines a set of weak learners based on the assumption that the weight combination for the final strong hypothesis in CAVIAR depends on both the weak learners and the training data. A regularization scheme using the nearest neighbor method is imposed in the testing stage to avoid overfitting. A closed form solution to the cost function is derived for this algorithm. We use a novel feature - the histogram of the deformation field between the MRI brain scan and the atlas which captures the structural changes in the scan with respect to the atlas brain - and this allows us to automatically discriminate between various classes within OASIS [1] using CAVIAR. We empirically show that CAVIAR significantly increases the performance of the weak classifiers by showcasing the performance of our technique on OASIS.
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High-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region, California
NASA Astrophysics Data System (ADS)
Ponce, D. A.; Mangan, M.; McPhee, D.
2013-12-01
A new high-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region greatly enhances previous magnetic interpretations that were based on older, low-resolution, and regional aeromagnetic data sets and provides new insights into volcano-tectonic processes. The surveyed area covers a 8,750 km2 NNW-trending swath situated between the Sierra Nevada to the west and the Basin and Range Province to the east. The surveyed area includes the volcanic centers of Mono Lake, Mono-Inyo Craters, Mammoth Mountain, Devils Postpile, and Long Valley Caldera. The NW-trending eastern Sierra frontal fault zone crosses through the study area, including the active Mono Lake, Silver Lake, Hartley Springs, Laurel Creek, and Hilton Creek faults. Over 6,000 line-kilometers of aeromagnetic data were collected at a constant terrain clearance of 150 m, a flight-line spacing of 400 m, and a tie-line spacing of 4 km. Data were collected via helicopter with an attached stinger housing a magnetic sensor using a Scintrex CS-3 cesium magnetometer. In the northern part of the survey area, data improve the magnetic resolution of the individual domes and coulees along Mono Craters and a circular shaped magnetic anomaly that coincides with a poorly defined ring fracture mapped by Kistler (1966). Here, aeromagnetic data combined with other geophysical data suggests that Mono Craters may have preferentially followed a pre-existing plutonic basement feature that may have controlled the sickle shape of the volcanic chain. In the northeastern part of the survey, aeromagnetic data reveal a linear magnetic anomaly that correlates with and extends a mapped fault. In the southern part of the survey, in the Sierra Nevada block just south of Long Valley Caldera, aeromagnetic anomalies correlate with NNW-trending Sierran frontal faults rather than to linear NNE-trends observed in recent seismicity over the last 30 years. These data provide an important framework for the further analysis of the
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Karaevskaia, E S; Demchenko, L S; Demidov, N É; Rivkina, E M; Bulat, S A; Gilichinskiĭ, D A
2014-01-01
Archaeal communities of permafrost deposits of King George Island and Bunger Hills Oasis (Antarctica) differing in the content of biogenic methane were analyzed using clone libraries of two 16S rRNA gene regions. Phylotypes belonging to methanogenic archaea were identified in all horizons.
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18 CFR 37.8 - Obligations of OASIS users.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Obligations of OASIS users. 37.8 Section 37.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME INFORMATION SYSTEMS § 37.8...
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El-Naggar, Hesham M
2010-01-01
The main activity in Siwa Oasis society is the agriculture, it depends on the groundwater. The agricultural drainage water and the unused saline water of naturally flowing springs are poured into four main salty lakes. This leads to an increase in the surface area of the saltwater lakes, marshes and rise in water table levels. to investigate some environmental engineering interventions to control the expansion of saltwater surface area in Siwa Oasis. Field visits, observation sheets and questionnaire survey with farmers were carried out to find out the main environmental problems in the Oasis. Environmental survey was carried out to collect different rocks and stones samples as natural construction materials from the desert that surrounds Siwa Oasis. Physical analyses, chemical composition and principal mechanical parameters were conducted on the collected samples. After the analysis, the safa rocks were the best natural construction materials in the Siwa Oasis. So, it could be used to build a construction wall around the salty lakes and marshes. Walls could convert the lakes into basins. The water will be evaporated at high rate during summer season by solar energy. After evaporation, the remaining salty rock named "karshef" can be easily collected from the lakes to be used as a low cost construction material for traditional building houses in Siwa Oasis. Therefore, the water level of lakes will be reduced to dryness and land could be reused as agricultural land. Among different rocks, safa rocks proved to be the best natural construction materials to construct a defense wall around the lakes and marshes. They will save about 80% of the concrete cost. The formed karshef rocks from the lakes will be used in the construction of the traditional building houses which will save about 90% of the concrete buildings. This intervention will save energy as it exchanges fuel consuming man-made material such as cement with naturally made material. This can reduce the green
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Fumal, T.E.; Rymer, M.J.; Seitz, G.G.
2002-01-01
Paleoseismic investigations across the Mission Creek strand of the San Andreas fault at Thousand Palms Oasis indicate that four and probably five surface-rupturing earthquakes occurred during the past 1200 years. Calendar age estimates for these earthquakes are based on a chronological model that incorporates radio-carbon dates from 18 in situ burn layers and stratigraphic ordering constraints. These five earthquakes occurred in about A.D. 825 (770-890) (mean, 95% range), A.D. 982 (840-1150), A.D. 1231 (1170-1290), A.D. 1502 (1450-1555), and after a date in the range of A.D. 1520-1680. The most recent surface-rupturing earthquake at Thousand Palms is likely the same as the A.D. 1676 ?? 35 event at Indio reported by Sieh and Williams (1990). Each of the past five earthquakes recorded on the San Andreas fault in the Coachella Valley strongly overlaps in time with an event at the Wrightwood paleoseismic site, about 120 km northwest of Thousand Palms Oasis. Correlation of events between these two sites suggests that at least the southernmost 200 km of the San Andreas fault zone may have ruptured in each earthquake. The average repeat time for surface-rupturing earthquakes on the San Andreas fault in the Coachella Valley is 215 ?? 25 years, whereas the elapsed time since the most recent event is 326 ?? 35 years. This suggests the southernmost San Andreas fault zone likely is very near failure. The Thousand Palms Oasis site is underlain by a series of six channels cut and filled since about A.D. 800 that cross the fault at high angles. A channel margin about 900 years old is offset right laterally 2.0 ?? 0.5 m, indicating a slip rate of 4 ?? 2 mm/yr. This slip rate is low relative to geodetic and other geologic slip rate estimates (26 ?? 2 mm/yr and about 23-35 mm/yr, respectively) on the southernmost San Andreas fault zone, possibly because (1) the site is located in a small step-over in the fault trace and so the rate is not be representative of the Mission Creek fault
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Lead Isotopes from the Upper Mississippi Valley District: A Regional Perspective
Millen, Timothy M.; Zartman, Robert E.; Heyl, Allen Van
1995-01-01
New lead isotopic data on galena from within and peripheral to the Upper Mississippi Valley lead-zinc district make it possible, by extending coverage to outlying locations, to trace the pathway traversed by the mineralizing fluids beyond the boundary of the main district. All but one of the samples exhibit elevated ratios of the radiogenic isotopes typical of the Upper Mississippi Valley ore deposits; 206PbP04Pb ranges from 19.38 to 24.46, 207PbP04Pb ranges from 15.73 to 16.24, and 208PbP04Pb ranges from 39.24 to 43.69. Galena from the Pints quarry near Waterloo, Iowa, has distinctly lower values of these ratios and may not be related paragenetically to the other samples. Otherwise, the lowest ratios are for samples in the southern part of the region in north-central Illinois, and the highest ratios are for samples to the northeast of the main district in the vicinity of Madison, Wisconsin. Thus, an isotopic pattern rather similar to that observed originally by Heyl and others (1966) prevails regionally, although the predominant fluid flow is now believed to have emanated from the Illinois Basin rather than from the Forest City Basin. Metal-bearing brines being driven northward out of the Illinois Basin probably played the key role in mineralization of the Upper Mississippi Valley district. Both the new and the previously reported lead ratios for the Upper Mississippi Valley district are plotted on 207PbP04Pb and Pb208/pb204Pb versus 206PbP04Pb diagrams, which permit their comparison and the calculation of refined slopes for the expanded data set. A two-stage model age for the time of mineralization can be determined from the 207PbP04Pb_Pb206/Pb204 slope, provided that the source age of the lead is known. With our limited know ledge of this source age, the time of mineralization cannot be tightly constrained but is permissive of a Permian or younger lateral secretion event, as suggested by other geochronological results.
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Fondaparinux and acute coronary syndromes: update on the OASIS 5-6 studies.
Schiele, François
2010-04-15
Anticoagulant therapy is a major component in the management of acute coronary syndromes (ACS). Four anticoagulant agents are currently commercially available for ACS, namely unfractionated heparin (UFH), enoxaparin, bivalirudin and fondaparinux. We describe the advantages of fondaparinux and the reasons that have hampered its uptake into routine management of ACS. Fondaparinux was shown to be efficacious in the prevention of deep vein thrombosis vs low-molecular-weight heparins, while in the setting of venous thrombo-embolic disease, it was shown to be noninferior to enoxaparin and UFH. Two pivotal studies have demonstrated the efficacy of fondaparinux as an anticoagulant in the setting of ACS, namely OASIS-5 in non-ST elevation ACS, and OASIS-6 in ST elevation myocardial infarction (MI). In OASIS-5, fondaparinux was shown to be noninferior to enoxaparin in terms of death, MI or refractory ischemia at 9 days. Furthermore, a 50% reduction in bleeding complications was obtained with fondaparinux vs enoxaparin, leading to a risk reduction for death. In OASIS-6, fondaparinux was shown to be superior to the comparator (UFH or placebo). European and North American guidelines give fondaparinux a Grade 1A and 1B recommendation respectively, but uptake of fondaparinux in routine practice has been slow. We explore reasons for this, such as prevailing doubts about the efficacy of fondaparinux in the setting of angioplasty, the problem of catheter thrombosis, and the lack of antidote in case of bleeding complications. With the exception of primary angioplasty, fondaparinux is as effective as enoxaparin or UFH, but is also associated with a considerable reduction in bleeding complications, and thus, an undeniable net clinical benefit.
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Alaya-Ltifi, Leila; Hayder-Benyahya, Nawel; Selmi, Slaheddine
2015-06-01
We investigated whether the proximity to the Gabès-Ghannouche factory complex of phosphate treatment, in south-eastern Tunisia, was associated with notable changes in the condition and health of Rufous bush robin (Cercotrichas galactotes) nestlings hatched in the neighbouring oasis habitat. Results demonstrated that excrements of nestlings hatched in one oasis close to the factory complex contained higher concentrations of lead and zinc than the excrements of nestlings from one oasis situated 20 km away. Furthermore, when effects of age and nestling number in the nest were controlled, nestlings hatched near the factory complex showed reduced tarsus length, rectrix length, haematocrit level and haemoglobin concentration, but higher levels of fluctuating asymmetry compared to those from the more distant oasis. Overall, results suggest that the proximity to the factory complex was associated with increased exposure to metals and deterioration in nestling condition and development.
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Eisenberg, Vered H; Valsky, Dan V; Yagel, Simcha
2018-03-24
Obstetric anal sphincter injury (OASI) is the most common cause of anal incontinence and ano-rectal symptoms in women 1 . Reported rates of anal incontinence following primary repair of OASI range between 15-61%, with a mean of 39% 2, 3 . Other possible complications of OASI include perineal pain, dyspareunia, and less commonly, abscess formation, wound breakdown, and rectovaginal fistulae. Symptom onset may occur immediately, several years postpartum, or only late in life when aging of tissues adds to the delivery insult. Having sustained an OASI may impact significantly on women's physical and emotional health. Missed OASI, inadequate repair or lack of follow up are potential sources of litigation 4 . The reported incidence of OASI may be as high as 4-6.6% 4 , averaging 2.9% in the UK 3 . The incidence is higher in primiparae (6.1%) than in multiparae (1.7%) 3 . Recent years are seeing an increased awareness and structured training programs, which appear to have resulted in an increase in the detection rate of OASI 3 . The following risk factors have been identified with varying risk rates reported 3 : Asian ethnicity (OR 2.27, 95% CI 2.14-2.41), nulliparity (relative risk [RR] 6.97, 95% CI 5.40-8.99), birth weight greater than 4 kg (OR 2.27, 95% CI 2.18-2.36), shoulder dystocia (OR 1.90, 95% CI 1.72-2.08), occipito-posterior position (RR 2.44, 95% CI 2.07-2.89), prolonged second stage of labor (up to RR 2.02, 95% CI 1.62-2.51 after four hours duration). Instrumental deliveries and episiotomy use have been extensively studied resulting in the following evidence: Vacuum delivery without episiotomy (OR 1.89, 95% CI 1.74-2.05); vacuum delivery with episiotomy is protective (OR 0.57, 95% CI 0.51-0.63); forceps delivery without episiotomy carries the highest potential risk (OR 6.53, 95% CI 5.57-7.64); and forceps delivery with episiotomy (OR 1.34, 95% CI 1.21-1.49). Other potential risk factors have been suggested with varying evidence such as advanced maternal age at
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Nimz, Gregory; Janik, Cathy; Goff, Fraser; Dunlap, Charles; Huebner, Mark; Counce, Dale; Johnson, Stuart D.
1999-01-01
Chemical and isotopic analyses of Dixie Valley regional waters indicated several distinct groups ranging in recharge age from Pleistocene (1000a). Geothermal field fluids (~12-14 ka) appear derived from water similar in composition to non thermal groundwater observed today in valley artesian well (also ~14 ka). Geothermal fluid interaction with mafic rocks (Humboldt Lopolith) appears to be common, and significant reaction with granodiorite may also occur. Despite widespread occurrence of carbonate rocks, large scale chemical interaction appears minor. Age asymmetry of the range, more extensive interaction with deep seated waters in the west, and distribution of springs and artesian wells suggest the existence of a regional upward hydrologic gradient with an axis in proximity to the Stillwater range.
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NASA Technical Reports Server (NTRS)
1973-01-01
The Sacramento Valley (40.5N, 121.5W) of California is the northern extension of the Central Valley, main agriculture region of the state. Hundreds of truck farms, vineyards and orchards can be seen throughout the length and breadth of the valley which was reclaimed from the desert by means of intensive and extensive irrigation projects.
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NASA Astrophysics Data System (ADS)
Bouaamlat, I.; Larabi, A.; Faouzi, M.
2014-12-01
The geographical location of Tafilalet oasis system (TOS) in the south of the valley of Ziz (Morocco) offers him a particular advantage on the plane of water potential. The surface water which comes from humid regions of the High Atlas and intercepted by a dam then converged through the watercourse of Ziz towards the plain of the TOS, have created the conditions for the formation of a water table relatively rich with regard to the local climatic conditions (arid climate with recurrent drought). Given the role of the water table in the economic development of the region, a hydrogeological study was conducted to understand the impact of artificial recharge and recurrent droughts on the development of the groundwater reserves of TOS. In this study, a three-dimensional model of groundwater flow was developed for the TOS, to assist the decision makers as a "management tool" in order to assess alternative schemes for development and exploitation of groundwater resources based on the variation of artificial recharge and drought. The results from this numerical investigation of the TOS aquifer shows that the commissioning of the dam to control the flows of extreme flood and good management of water releases, has avoided the losses of irrigation water and consequently the non-overexploitation of the groundwater. So that with one or two water releases per year from the dam of flow rate more than 28 million m3/year it is possible to reconstruct the volume of water abstracted by wells. The idea of lowering water table by pumping wells is not exactly true, as well the development of groundwater abstraction has not prevented the wound of water table in these last years, the pumping wells accompanied more than it triggers the lowering of water table and it is mainly the succession of dry periods causing the decreases of the piezometric level. This situation confirms the important role that groundwater plays as a "buffer" during the drought periods.
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NASA Astrophysics Data System (ADS)
Zhang, Yongyong; Zhao, Wenzhi; He, Jianhua; Fu, Li
2018-02-01
Macropore flow not only provides a fast pathway for water and solute transport and increases the risks of water and nutrient loss but also enhances soil aeration and groundwater recharge. However, macropore flow characteristics in irrigated oasis soils subject to continuous crop cultivation are poorly understood. This study was to investigate the effect of continuous cultivation on soil properties and macropore flow and to quantify the changes in macropore flow characteristics in an old oasis field (>50 years of cultivation, OOF), young oasis field (20 years, YOF), and adjacent uncultivated sandy area (0 year, USL) in Northwest China. Triplicate soil samples were collected from each site to investigate soil properties. Dye tracer experiments with also three replicates were conducted at each site. The degree of macropore flow (i.e., parameters of macropore flow) was highest at the OOF, intermediate at the YOF, and minimal at the USL. The macropore flow fraction (i.e., fraction of total infiltration flows through macropore flow pathways) at the OOF was 3.4 times greater than at the USL. The heterogeneous infiltration pattern at the OOF was dominated by macropore flow, while funnel flow was predominant at the USL. Long-term irrigation with silt-laden river water has increased silt + clay contents of the oasis soils. Irrigation and high-input crop cultivation also increased organic matter. These changes in soil properties contributed to the interaggregate voids formation. The conversion of native desert soils to irrigated croplands increases the degree of macropore flow, which might enhance groundwater recharge in the desert-oasis ecotone.
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Singh, J; Gautam, S; Bhushan Pant, A
2012-12-22
The survival of Antarctic flora under ozone depletion depends on their ability to acclimate against increasing UV—B radiation by employing photo protective mechanisms either by avoiding or repairing UV—B damage. A fifteen days experiment was designed to study moss (Bryum argenteum) and lichen (Umbilicaria aprina) under natural UV—B exposure and under UV filter frames at the Maitri region of Schirmacher oasis, East Antarctica. Changes in UV absorbing compounds, phenolics, carotenoids and chlorophyll content were studied for continuous fifteen days and significant changes were observed in the UV exposed plants of B. argenteum and U. aprina. The change in the UV absorbing compounds was more significant in B. argenteum (P<0.0001) than U. aprina (P<0.0002). The change in phenolic contents and total carotenoid content was significant (P<0.0001) in both B. argenteum and lichen U. aprina indicating that the increase in UV absorbing compounds, phenolic contents and total carotenoid content act as a protective mechanism against the deleterious effect of UV—B radiations.
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Dohm, J.M.; Ferris, J.C.; Barlow, N.G.; Baker, V.R.; Mahaney, W.C.; Anderson, R.C.; Hare, T.M.
2004-01-01
The northwestern slope valleys region is a prime candidate site for future science-driven Mars exploration because it records Noachian to Amazonian Tharsis development in a region that encapsulates (1) a diverse and temporally extensive stratigraphic record, (2) at least three distinct paleohydrologic regimes, (3) gargantuan structurally controlled flood valleys that generally correspond with gravity and magnetic anomalies, possibly marking ancient magnetized rock materials exposed by fluvial activity, (4) water enrichment, as indicated by Mars Odyssey and impact crater analyses, (5) long-lived magma and ground water/ice interactions that could be favorable for the development and sustenance of life, and (6) potential paleosol development. This region has high probability to yield significant geologic, climatic, and exobiologic information that could revolutionize our understanding of Mars. ?? 2003 Elsevier Ltd. All rights reserved.
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Fridrich, Christopher J.; Thompson, Ren A.
2011-01-01
The Death Valley region, of southeast California and southwest Nevada, is distinct relative to adjacent regions in its structural style and resulting topography, as well as in the timing of basin-range extension. Cenozoic basin-fill strata, ranging in age from greater than or equal to 40 to approximately 2 million years are common within mountain-range uplifts in this region. The tectonic fragmentation and local uplift of these abandoned basin-fills indicate a multistage history of basin-range tectonism. Additionally, the oldest of these strata record an earlier, pre-basin-range interval of weak extension that formed broad shallow basins that trapped sediments, without forming basin-range topography. The Cenozoic basin-fill strata record distinct stratigraphic breaks that regionally cluster into tight age ranges, constrained by well-dated interbedded volcanic units. Many of these stratigraphic breaks are long recognized formation boundaries. Most are angular unconformities that coincide with abrupt changes in depositional environment. Deposits that bound these unconformities indicate they are weakly diachronous; they span about 1 to 2 million years and generally decrease in age to the west within individual basins and regionally, across basin boundaries. Across these unconformities, major changes are found in the distribution and provenance of basin-fill strata, and in patterns of internal facies. These features indicate rapid, regionally coordinated changes in strain patterns defined by major active basin-bounding faults, coincident with step-wise migrations of the belt of active basin-range tectonism. The regionally correlative unconformities thus record short intervals of radical tectonic change, here termed "tectonic reorganizations." The intervening, longer (about 3- to 5-million-year) interval of gradual, monotonic evolution in the locus and style of tectonism are called "tectonic stages." The belt of active tectonism in the Death Valley region has abruptly
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Jeong, Yoonah; Schäffer, Andreas; Smith, Kilian
2017-05-01
Oasis hydrophilic lipophilic balance ® (Oasis HLB) is commonly employed in solid phase extraction (SPE) of environmental contaminants and within polar organic chemical integrative passive samplers (POCIS). In this study batch experiments were carried out to evaluate the relative affinity of a range of relevant organic pollutants to Oasis HLB in aqueous systems. The influence of sorbate concentration, temperature, pH, and salinity on the equilibrium sorption was investigated. Equilibrium partition ratios (K D ) of 28 compounds were determined, ranging over three orders of magnitude from 1.16 × 10 3 L/kg (atenolol) to 1.07 × 10 6 L/kg (isoproturon). The Freundlich model was able to describe the equilibrium partitioning to Oasis HLB, and an analysis of the thermodynamic parameters revealed the spontaneous and exothermic nature of the partitioning process. Ionic strength had only a minor effect on the partitioning, whereas pH had a considerable effect but only for ionizable compounds. The results show that apolar interactions between the Oasis HLB and analyte mainly determine the equilibrium partitioning. These research findings can be used to optimize the application of SPE and POCIS for analyses of environmental contaminants even in complex mixtures. Copyright © 2017 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Zhu, Xiaobin; Wu, Jichun; Nie, Huijun; Guo, Fei; Wu, Jianfeng; Chen, Kouping; Liao, Penghui; Xu, Hongxia; Zeng, Xiankui
2018-06-01
Inter-basin water transfer projects (IBWTPs) can involve basins as water donors and water receivers. In contrast to most studies on IBWTPs, which mainly impact the surface-water eco-environment, this study focuses on the impacts of an IBWTP on groundwater and its eco-environment in a water donor basin in an arid area, where surface water and groundwater are exchanged. Surface water is assumed to recharge groundwater and a groundwater numerical simulation model was constructed using MODFLOW. The model was used to quantitatively evaluate the impact of an IBWTP located in the upstream portion of Nalenggele River (the biggest river in the Qaidam basin, Northwest China). The impact involved decrease in spring flow, drawdown of groundwater, reduction in oasis area, and an increase in species replacement of oasis vegetation in the midstream and downstream of the river. Results show that the emergence sites of springs at the front of the oasis will move 2-5 km downstream, and the outflow of springs will decrease by 42 million m3/a. The maximum drawdown of groundwater level at the front of the oasis will be 3.6 m and the area across which groundwater drawdown exceeds 2.0 m will be about 59.02 km2, accounting for 2.71% of the total area of the oasis. Under such conditions, reeds will gradually be replaced by Tamarix, shrubs, and other alternative plant species. These findings have important implications for the optimization of water resource allocation and protection of the eco-environment in arid regions.
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1973-06-22
SL2-04-179 (22 June 1973) --- The Sacramento Valley (40.5N, 121.5W) of California is the northern extension of the Central Valley, main agriculture region of the state. Hundreds of truck farms, vineyards and orchards can be seen throughout the length and breadth of the valley which was reclaimed from the desert by means of intensive and extensive irrigation projects. Photo credit: NASA
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NASA Astrophysics Data System (ADS)
Ismael, Hossam
2015-04-01
Undoubtedly, El-Kharga Oasis monumental sites are considered an important part of our world's cultural heritage in the South Western Desert of Egypt. These sites are scattered on the floor of the oasis representing ancient civilizations. The Roman stone monuments in Kharga represent cultural heritage of an outstanding universal value. Such those monuments have suffered weathering deterioration. There are various elements which affect the weathering process of stone monuments: climate conditions, shapes of cultural heritages, exposed time periods, terrains, and vegetation around them, etc. Among these, climate conditions are the most significant factor affecting the deterioration of Archeological sites in Egypt. El- Kharga Oasis belongs administratively to the New Valley Governorate. It is located in the southern part of the western desert of Egypt, lies between latitudes 22°30'14" and 26°00'00" N, and between 30°27'00" and 30°47'00" E. The area of El Kharga Oasis covers about 7500 square kilometers. Pilot studies were carried out on the EI-Nadura Temple, composed of sandstones originating from the great sand sea. The major objective of this study is to monitor and measure the weathering features and the weathering rate affecting the building stones forming El-Nadora Roman building rocks in cubic cm. To achieve these aims, the present study used analysis of climatic data such as annual and seasonal solar radiation, Monthly average number of hours of sunshine, maximum and minimum air temperatures, wind speed, which have obtained from actual field measurements and data Meteorological Authority of El-Kharga station for the period 1977 to 2010 (33 years), and from the period 1941-2050 (110 years) as a long term of temperature data. Several samples were collected and examined by polarizing microscopy (PLM), X-ray diffraction analysis (XRD) and scanning electron microscopy equipped with an energy dispersive X-ray analysis system (SEM-EDX). The results were in
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Visscher, A P; Lam, T J; Hart, N; Felt-Bersma, R J F
2014-05-01
Our aim was to evaluate alterations in anorectal function after anal sphincteroplasty for third-degree obstetric anal sphincter injury (OASI) in relation to clinical outcome. In this retrospective, descriptive, cross-sectional study conducted between 1998 and 2008, women with persisting fecal incontinence (FI) after 3a OASI and all women with grade 3b or 3c OASI were sent for anorectal function evaluation (AFE) consisting of anal manometry and endosonography 3 months after sphincteroplasty. In 2011, questionnaires regarding FI (Vaizey/Wexner), urinary incontinence (UI) [International Consultation on Incontinence Questionnaire Short Form (ICIQ-SF)], sexual function [Female Sexual Function Index (FSFI)], and quality of life (QOL) (Rand-36) were sent and women were asked to undergo additional AFE. Sixty-six women underwent AFE. Mean follow-up was 5.0 years. Forty (61%) patients returned questionnaires regarding FI and UI. Prevalence of FI was 63% flatus, 50% liquid stool, and 20% solid stool. Thirty-two of 40 also reported on QOL and SF. Sexual dysfunction was present in the majority of women (cutoff value 26.55) and more pronounced in larger OASI. Sixteen of 40 women underwent additional AFE. Women with combined internal (IAS) and external (EAS) anal sphincter injury (n = 6) had worse FI (P < 0.050) and lower anal pressures (P = 0.040) than women with isolated EAS injury (n = 10). Follow-up after third-degree OASI suggests poor anorectal and sexual function. Women with combined external and internal OASI show more deterioration in anorectal function and experience worse FI. Therefore, special attention should be paid to these women in order to mitigate these symptoms later in life.
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Overdiagnosis and rising rate of obstetric anal sphincter injuries (OASIS): time for reappraisal.
Sioutis, D; Thakar, R; Sultan, A H
2017-11-01
To determine the accuracy of clinical diagnosis of obstetric anal sphincter injuries (OASIS) using three-dimensional (3D) endoanal ultrasound (EA-US) and to compare symptoms and anal manometry measurements between women with anal sphincters adequately repaired and those with persistent anal sphincter defects. The EA-US images of women with clinically diagnosed and repaired OASIS, defined as third- or fourth-degree perineal tear, who attended the perineal clinic at Croydon University Hospital over a 10-year period (2003-2013) were reanalyzed by a single expert blind to symptoms and the results of clinical examination. St Mark's Incontinence Scores (SMIS) and anal manometry measurements were obtained and compared between women with an intact anal sphincter and those with an anal sphincter scar and between those with an intact anal sphincter and those with a defect. Anal manometry measurements were compared between women with an external anal sphincter (EAS) defect and those with an internal anal sphincter (IAS) defect. The images of 908 women were reanalyzed. No evidence of OASIS was found in 64 (7.0%) women, an EAS scar alone was detected in 520 (57.3%) and an anal sphincter defect in 324 (35.7%). Of the 324 women with a defect, 112 had an EAS defect, 90 had an IAS defect and 122 had a combined IAS and EAS defect. SMIS results were significantly higher in women with an anal sphincter defect compared with those with no evidence of OASIS (P = 0.018), but there was no significant difference in scores between women with an intact sphincter and those with an EAS scar only. Women with a defect had a significantly lower maximum resting pressure (median (range), 44 (8-106) vs 55 (29-86) mmHg; P < 0.001) and maximum squeeze pressure (median (range), 74 (23-180) vs 103 (44-185) mmHg; P < 0.001) compared with those in the intact group. Similar, but less marked, differences were observed in women with an EAS scar compared with those who had an intact anal sphincter
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Zhang, Peng Peng; Pu, Xiao Zhen; Zhang, Wang Feng
2018-03-01
To reveal the regulatory mechanism of agricultural management practices on soil quality, an experiment was carried out to study the different cropping system and straw management on soil organic carbon and fractions and soil enzyme activity in farmland of arid oasis region, which would provide a scientific basic for enhancing agricultural resources utilization and sustainable development. In crop planting planning area, we took the mainly crop (cotton, wheat, maize) as research objects and designed long-term continues cropping and crop rotation experiments. The results showed that the soil organic carbon (SOC), soil microbial biomass C, labile C, water-soluble organic C, and hot-water-soluble organic C content were increased by 3.6%-9.9%, 41.8%-98.9%, 3.3%-17.0%, 11.1%-32.4%, 4.6%-27.5% by crop rotation compared to continues cropping, and 12%-35.9%, 22.4%-49.7%, 30.7%-51.0%, 10.6%-31.9%, 41.0%-96.4% by straw incorporated compared to straw removed, respectively. The soil catalase, dehydrogenase, β-glucosidase, invertase glucose, cellulase glucose activity were increased by 6.4%-10.9%, 6.6%-18.8%, 5.9%-15.3%, 10.0%-27.4%, 28.1%-37.5% by crop rotation compared to continues cropping, and 31.4%-47.5%, 19.9%-46.6%, 13.8%-20.7%, 19.8%-55.6%, 54.1%-70.9% by straw incorporated compared to straw removed, respectively. There were significant positive linear correlations among SOC, labile SOC fractions and soil enzyme. Therefore, we concluded that labile SOC fractions and soil enzyme were effective index for evaluating the change of SOC and soil quality. Based on factor analysis, in arid region, developing agricultural production using cropland management measures, such as straw-incorporated and combined short-term continues cotton and crop rotation, could enhance SOC and labile SOC fractions contents and soil enzyme activity, which could improve soil quality and be conducive to agricultural sustainable development.
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Regional Aquifer-System Analysis— Appalachian Valley and Piedmont
,
2004-01-01
The Regional Aquifer-System Analysis Program, RASA, represents a systematic effort to study a number of the Nation’s most important aquifer systems, which, in aggregate, underlie much of the country and which represent an important component of the Nation’s total water supply. In general, the boundaries of these studies are identified by the hydrologic extent of each system and, accordingly, transcend the political subdivisions to which investigations have often arbitrarily been limited in the past. The broad objective for each study is to assemble geologic, hydrologic, and geochemical information, to analyze and develop an understanding of the system, and to develop predictive capabilities that will contribute to the effective management of the system. The use of computer simulation is an important element of the RASA studies to develop an understanding of the natural, undisturbed hydrologic system and the changes brought about in it by human activities and to provide a means of predicting the regional effects of future pumping or other stresses.The final interpretive results of the RASA Program are presented in a series of U.S. Geological Survey Professional Papers that describe the geology, hydrology, and geochemistry of each regional aquifer system. Each study within the RASA Program is assigned a single Professional Paper number beginning with Professional Paper 1400.This paper, Professional Paper 1422, represents the Regional Aquifer-System Analysis— Appalachian Valley and Piedmont. It is published as several individual volumes over several years.
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NASA Astrophysics Data System (ADS)
Shchetnikov, A. A.; Klementiev, A. M.; Filinov, I. A.; Semeney, E. Yu.
2015-03-01
This work presents the data on new finds of fossil macrotheriofauna in the reference sections of the Upper Neopleistocene sediments in the Tunka rift valley (southwestern Baikal Region). The osteological material of a number of Late Neopleistocene mammals including extinct species rare for the Baikal region such as Crocuta spelaea, Panthera spelaea, and Spirocerus kiakhtensis (?) was directly dated with a radiocarbon (AMS) method. The obtained 14C data (18000-35000 years) allow one to rejuvenate significantly the upper limit of the common age interval of habitat of these animals in southern part of Eastern Siberia. Cave hyena and spiral-horned antelope lived in the Tunka rift valley in the Baikal region in Late Kargino time (37-24 ka), and cave lion survived the maximum in the Sartan cryochron in the region (21-20 ka). The study of collected paleontological collections provides a basis for selection of independent Kargino (MIS 3) faunal assemblages to use them for regional biostratigraphic analysis of Pleistocene deposits. Radiocarbon age dating of samples allows one to attribute confidently all paleofaunal remains available to the second half of the Late Pleistocene.
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NASA Astrophysics Data System (ADS)
Mueller, N.; Kerstetter, S. R.; Katopody, D. T.; Oldow, J. S.
2016-12-01
The NW-striking, right-oblique Fish Lake Valley fault zone (FLVFZ) forms the northern segment of the longest active structure in the western Great Basin; the Death Valley - Furnace Creek - Fish Lake Valley fault system. Since the mid-Miocene, 50 km of right-lateral displacement is documented on the southern FLVFZ and much of that displacement was and is transferred east and north on active WNW left-lateral faults. Prior to the Pliocene, displacement was transferred east and north on a low-angle detachment. Displacement on the northern part of the FLVFZ continues and is transferred to a fanned array of splays striking (west to east) WNW, NNW, ENE and NNE. To determine the displacement budget on these structures, we conducted a gravity survey to determine subsurface basin morphology and its relation to active faults. Over 2450 stations were collected and combined with existing PACES and proprietary data for a total of 3388 stations. The data were terrain corrected and reduced to a 2.67 g/cm3 density to produce a residual complete Bouguer anomaly. The eastern part of northern Fish Lake Valley is underlain by several prominent gravity lows forming several sub-basins with maximum RCBA values ranging from -24 to -28 mGals. The RCBA was inverted for depth using Geosoft Oasis Montaj GM-SYS 3D modeling software. Density values for the inversion were constrained by lithologic and density logs from wells that penetrate the entire Cenozoic section into the Paleozoic basement. Best fitting gravity measurements taken at the wellheads yielded an effective density of 2.4 g/cm3 for the basin fill. Modeled basement depths range between 2.1 to 3 km. The sub-basins form an arc opening to the NW and are bounded by ENE and NNE faults in the south and NS to NNW in the north. At the northern end of the valley, the faults merge with ENE left-lateral strike slip faults of the Mina deflection, which carries displacement to NW dextral strike-slip faults of the central Walker Lane.
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Ramo, O.T.; Calzia, J.P.; Kosunen, P.J.
2002-01-01
Mesozoic granitoid plutons in the southern Death Valley region of southeastern California reveal substantial compositional and isotopic diversity for Mesozoic magmatism in the southwestern US Cordillera. Jurassic plutons of the region are mainly calc-alkaline mafic granodiorites with ??Ndi of -5 to -16, 87Sr/86Sri of 0.707-0.726, and 206Pb/204Pbi of 17.5-20.0. Cretaceous granitoids of the region are mainly monzogranites with ??Ndi of -6 to -19, 87Sr/86Sri of 0.707-0.723, and 206Pb/204Pbi of 17.4-18.6. The granitoids were generated by mixing of mantle-derived mafic melts and pre-existing crust - some of the Cretaceous plutons represent melting of Paleoproterozoic crust that, in the southern Death Valley region, is exceptionally heterogeneous. A Cretaceous gabbro on the southern flank of the region has an unuasually juvenile composition (??Ndi -3.2, 87Sr/86Sri 0.7060). Geographic position of the Mesozoic plutons and comparison with Cordillera plutonism in the Mojave Desert show that the Precambrian lithosphere (craton margin) in the eastern Mojave Desert region may consists of two crustal blocks separated by a more juvenile terrane.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Goff, Fraser; Bergfeld, Deborah; Janik, C.J.
2002-08-01
This report tabulates an extensive geochemical database on waters, gases, scales, rocks, and hot-spring deposits from the Dixie Valley region, Nevada. The samples from which the data were obtained were collected and analyzed during 1996 to 1999. These data provide useful information for ongoing and future investigations on geothermal energy, volcanism, ore deposits, environmental issues, and groundwater quality in this region.
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Geochemistry of waters in the Valley of Ten Thousand Smokes region, Alaska
Keith, T.E.C.; Thompson, J.M.; Hutchinson, R.A.; White, L.D.
1992-01-01
Meteoric waters from cold springs and streams outside of the 1912 eruptive deposits filling the Valley of Ten Thousand Smokes (VTTS) and in the upper parts of the two major rivers draining the 1912 deposits have similar chemical trends. Thermal springs issue in the mid-valley area along a 300-m lateral section of ash-flow tuff, and range in temperature from 21 to 29.8??C in early summer and from 15 to 17??C in mid-summer. Concentrations of major and minor chemical constituents in the thermal waters are nearly identical regardless of temperature. Waters in the downvalley parts of the rivers draining the 1912 deposits are mainly mixtures of cold meteoric waters and thermal waters of which the mid-valley thermal spring waters are representative. The weathering reactions of cold waters with the 1912 deposits appear to have stabilized and add only subordinate amounts of chemical constituents to the rivers relative to those contributed by the thermal waters. Isotopic data indicate that the mid-valley thermal spring waters are meteoric, but data is inconclusive regarding the heat source. The thermal waters could be either from a shallow part of a hydrothermal system beneath the 1912 vent region or from an incompletely cooled, welded tuff lens deep in the 1912 ash-flow sheet of the upper River Lethe area. Bicarbonate-sulfate waters resulting from interaction of near-surface waters and the cooling 1953-1968 southwest Trident plug issue from thermal springs south of Katmai Pass and near Mageik Creek, although the Mageik Creek spring waters are from a well-established, more deeply circulating hydrothermal system. Katmai caldera lake waters are a result of acid gases from vigorous drowned fumaroles dissolving in lake waters composed of snowmelt and precipitation. ?? 1992.
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River-damming, late-Quaternary rockslides in the Ötz Valley region (Tyrol, Austria)
NASA Astrophysics Data System (ADS)
Dufresne, A.; Ostermann, M.; Preusser, F.
2018-06-01
The Ötz Valley and adjacent regions in Tyrol (Austria) have been repeatedly affected by large rockslope failures following deglaciation. Six rockslides, each over 107 m3 in volume, were emplaced into the Ötz and Inn valleys, five of which formed persistent rockslide dams. Even though catastrophic rockslope failures are short-lived events (commonly minutes) they can have long-lasting impacts on the landscape. For example, large fans have built in the Ötz Valley and knickpoints persist at the former dam sites even though the Ötz River has eroded through the deposits during the past thousands of years; exact age-constraints of rockslide dam failure, however, are still scarce. Empirical, geomorphic stability indices from the literature successfully identified the least and the most stable dams of this group, whereas the rest remain inconclusive with some indices variably placing the dams in the stable, unstable, and uncertain categories. This shows (a) that further index calibrations and (b) better age constraints on dam formation and failure are needed, and (c) that the exact processes of dam failure are not always trivial to pinpoint for ancient (partially) breached dams. This study is a contribution towards better constraining the nature and landscape impact of dam formation following large rockslope failures.
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NASA Astrophysics Data System (ADS)
Orabi, H.; El Beshtawy, M.; Osman, R.; Gadallah, M.
2015-05-01
In the Eocene part of the Siwa Oasis, the larger foraminifera are represented by the genera Nummulites, Arxina, Operculina, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella, Gaziryina and Discocyclina in order of abundance. Operculina continues up to the early Oligocene as modern representatives in tropical regions, while the other genera became extinct. Nevertheless, the most common larger foraminiferal genus Lepidocyclina (Nephrolepidina) appears only in the lowermost Oligocene. In spite of the Eocene-Oligocene (E/O) transition is thought to have been attended by major continental cooling at northern middle and high latitudes, we discover that at the Siwa Oasis, there is a clear warming trend from the late Eocene (extinction level of Nummulites, Sphaerogypsina, Asterocyclina, Grzybowskia, Silvestriella and Discocyclina) to the early Oligocene is observed due to the high abundance of Operculina and occurrence of kaolinite and gypsiferous shale deposits in both Qatrani and El Qara formations (Oligocene) at this transition. The El Qara Formation is a new rock unit proposed herein for the Oligocene (Rupelian age) in the first time. Several episodes of volcanic activity occurred in Egypt during the Cenozoic. Mid Tertiary volcanicity was widespread and a number of successive volcanic pulses are starting in the late Eocene. The release of mantle CO2 from this very active volcanic episode may have in fact directly caused the warm Eocene-Oligocene greenhouse climate effect.
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18 CFR 37.6 - Information to be posted on the OASIS.
Code of Federal Regulations, 2011 CFR
2011-04-01
... protocols, information regarding the transmission system necessary to enable prudent business decision... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY...
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18 CFR 37.6 - Information to be posted on the OASIS.
Code of Federal Regulations, 2010 CFR
2010-04-01
... protocols, information regarding the transmission system necessary to enable prudent business decision... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY...
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NASA Technical Reports Server (NTRS)
Parker, T. J.; Pieri, D. C.
1985-01-01
Three major valley tapes were identified in the SW Margaritefer Sinus and Argyre regions. Two are restricted to specific geologic units while the third is independent of the geology. The first type (the small valley networks) are found within the channeled and subdued plains unit in the eastern half of the map, in the grooved and channeled plains unit north of Nirgal Vallis, and in scattered instances in the cratered plateau unit north of Argyre. The even smaller valleys just inside Argyre's rim and on the inner slopes of many large craters are not directly related to the processes which formed the small valleys but are a result, instead, of post-impact modification of the crater walls. The second type of valley network is represented by Nirgal Vallis and the similar, shorter continuation of it to the west. This type is found only in the smooth plains material west of Uzboi Vallis in the map area. The third type of valley network is that of the Uzbol-Holden-Ladon valles system. This system is related to catastrophic outflow from Argyre Basin and is topographically rather than geologically controlled.
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NASA Astrophysics Data System (ADS)
Viani, Cristina; Machguth, Horst; Huggel, Christian; Godio, Alberto; Perotti, Luigi; Giardino, Marco
2017-04-01
Aosta Valley (NW-Alps, Italy) is the region with the largest glaciarized area of Italy (133.73 km2). Like the other alpine regions it has shown a significant glacier retreat starting from the end of the Little Ice Age (LIA, ca. 1850 AD), by losing about 60% of its glaciarized area. As a direct consequence of glacier shrinkage, within glacially-sculpted landscapes, glacier-bed overdeepenings become exposed, offering suitable conditions for glacier lakes formation. In the Aosta Valley region, about 200 glacier lakes have been recognized in different time periods within LIA maximum extent boundaries, mainly dammed by bedrock landforms. With respect to human activities, glacier lakes represent both opportunities (e.g. Miage lake for tourism) and risks (e.g. outburst flood of the Gran Croux lake above Cogne in August 2016) in such a densely populated and developed region. The objective of this contribution is to assess locations of possible future glacier lakes in the Aosta Valley by using the GlabTop2 model (Glacier Bed Topography model version 2). Understanding where future lakes will appear is of fundamental importance for the identification of potential hazards and the interpretation of conditioning factors and dynamics. We first assessed ice thickness and consequently glacier bed topography over large glaciated areas of the region, by using both glaciers outlines related to 1999 (provided by the GlaRiskAlp project) and the regional DEM of 1990 (provided by the Aosta Valley Region) as input data. We performed several runs by varying different input parameters (e,g.: pixel size and basal shear stress). Then we compared modelled results on selected test glaciers (Rutor and Grand Etrèt) with available GPR data. As a validation, we also carried out a GPR survey during summer 2016 on the central area of Indren Glacier (Monte Rosa massif) where GlabTop2 shows the presence of a possible subglacial overdeepening morphology. We found that ice thickness and consequently the
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NASA Astrophysics Data System (ADS)
Voldoire, Aurore; Decharme, Bertrand; Pianezze, Joris; Lebeaupin Brossier, Cindy; Sevault, Florence; Seyfried, Léo; Garnier, Valérie; Bielli, Soline; Valcke, Sophie; Alias, Antoinette; Accensi, Mickael; Ardhuin, Fabrice; Bouin, Marie-Noëlle; Ducrocq, Véronique; Faroux, Stéphanie; Giordani, Hervé; Léger, Fabien; Marsaleix, Patrick; Rainaud, Romain; Redelsperger, Jean-Luc; Richard, Evelyne; Riette, Sébastien
2017-11-01
This study presents the principles of the new coupling interface based on the SURFEX multi-surface model and the OASIS3-MCT coupler. As SURFEX can be plugged into several atmospheric models, it can be used in a wide range of applications, from global and regional coupled climate systems to high-resolution numerical weather prediction systems or very fine-scale models dedicated to process studies. The objective of this development is to build and share a common structure for the atmosphere-surface coupling of all these applications, involving on the one hand atmospheric models and on the other hand ocean, ice, hydrology, and wave models. The numerical and physical principles of SURFEX interface between the different component models are described, and the different coupled systems in which the SURFEX OASIS3-MCT-based coupling interface is already implemented are presented.
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OASIS - ORBIT ANALYSIS AND SIMULATION SOFTWARE
NASA Technical Reports Server (NTRS)
Wu, S. C.
1994-01-01
The Orbit Analysis and Simulation Software, OASIS, is a software system developed for covariance and simulation analyses of problems involving earth satellites, especially the Global Positioning System (GPS). It provides a flexible, versatile and efficient accuracy analysis tool for earth satellite navigation and GPS-based geodetic studies. To make future modifications and enhancements easy, the system is modular, with five major modules: PATH/VARY, REGRES, PMOD, FILTER/SMOOTHER, and OUTPUT PROCESSOR. PATH/VARY generates satellite trajectories. Among the factors taken into consideration are: 1) the gravitational effects of the planets, moon and sun; 2) space vehicle orientation and shapes; 3) solar pressure; 4) solar radiation reflected from the surface of the earth; 5) atmospheric drag; and 6) space vehicle gas leaks. The REGRES module reads the user's input, then determines if a measurement should be made based on geometry and time. PMOD modifies a previously generated REGRES file to facilitate various analysis needs. FILTER/SMOOTHER is especially suited to a multi-satellite precise orbit determination and geodetic-type problems. It can be used for any situation where parameters are simultaneously estimated from measurements and a priori information. Examples of nonspacecraft areas of potential application might be Very Long Baseline Interferometry (VLBI) geodesy and radio source catalogue studies. OUTPUT PROCESSOR translates covariance analysis results generated by FILTER/SMOOTHER into user-desired easy-to-read quantities, performs mapping of orbit covariances and simulated solutions, transforms results into different coordinate systems, and computes post-fit residuals. The OASIS program was developed in 1986. It is designed to be implemented on a DEC VAX 11/780 computer using VAX VMS 3.7 or higher. It can also be implemented on a Micro VAX II provided sufficient disk space is available.
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Belcher, Wayne R.; Elliott, Peggy E.; Geldon, Arthur L.
2001-01-01
The Death Valley regional ground-water flow system encompasses an area of about 43,500 square kilometers in southeastern California and southern Nevada, between latitudes 35? and 38?15' north and longitudes 115? and 117?45' west. The study area is underlain by Quaternary to Tertiary basin-fill sediments and mafic-lava flows; Tertiary volcanic, volcaniclastic, and sedimentary rocks; Tertiary to Jurassic granitic rocks; Triassic to Middle Proterozoic carbonate and clastic sedimentary rocks; and Early Proterozoic igneous and metamorphic rocks. The rock assemblage in the Death Valley region is extensively faulted as a result of several episodes of tectonic activity. This study is comprised of published and unpublished estimates of transmissivity, hydraulic conductivity, storage coefficient, and anisotropy ratios for hydrogeologic units within the Death Valley region study area. Hydrogeologic units previously proposed for the Death Valley regional transient ground-water flow model were recognized for the purpose of studying the distribution of hydraulic properties. Analyses of regression and covariance were used to assess if a relation existed between hydraulic conductivity and depth for most hydrogeologic units. Those analyses showed a weak, quantitatively indeterminate, relation between hydraulic conductivity and depth.
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18 CFR 37.6 - Information to be posted on the OASIS.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...
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18 CFR 37.6 - Information to be posted on the OASIS.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...
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18 CFR 37.6 - Information to be posted on the OASIS.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Information to be posted on the OASIS. 37.6 Section 37.6 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT OPEN ACCESS SAME-TIME...
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Moreo, Michael T.; Halford, Keith J.; La Camera, Richard J.; Laczniak, Randell J.
2003-01-01
Ground-water withdrawals from 1913 through 1998 from the Death Valley regional flow system have been compiled to support a regional, three-dimensional, transient ground-water flow model. Withdrawal locations and depths of production intervals were estimated and associated errors were reported for 9,300 wells. Withdrawals were grouped into three categories: mining, public-supply, and commercial water use; domestic water use; and irrigation water use. In this report, groupings were based on the method used to estimate pumpage. Cumulative ground-water withdrawals from 1913 through 1998 totaled 3 million acre-feet, most of which was used to irrigate alfalfa. Annual withdrawal for irrigation ranged from 80 to almost 100 percent of the total pumpage. About 75,000 acre-feet was withdrawn for irrigation in 1998. Annual irrigation withdrawals generally were estimated as the product of irrigated acreage and application rate. About 320 fields totaling 11,000 acres were identified in six hydrographic areas. Annual application rates for high water-use crops ranged from 5 feet in Penoyer Valley to 9 feet in Pahrump Valley. The uncertainty in the estimates of ground-water withdrawals was attributed primarily to the uncertainty of application rate estimates. Annual ground-water withdrawal was estimated at about 90,000 acre-feet in 1998 with an assigned uncertainty bounded by 60,000 to 130,000 acre-feet.
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Theory of stability, and regulation and control of ecological system in oasis
NASA Astrophysics Data System (ADS)
Pan, Xiaoling; Chao, Jiping
2003-06-01
Starting with analysis on the evolving course of oasis and the characteristics and evolution of transitional zone between oasis and desert, in consideration of ecological elements including plant stomata resistance, area covered by vegetation, and physical elements including albedo of vegetation and bare soil, atmosphere temperature, and humidity, under the condition of the balance among net radiation flux, latent heat flux, and sensible heat flux, the following are calculated: temperatures of vegetation and bare soil in different conditions, as well as the evapotranspiration rate of ecosystem. Analysis on evapotranspiration rate indicates that it depends on both the climate of environment and the physiological and ecological conditions of plants. On certain conditions, the evapotranspiration rate of transitional zone between oasis and desert (i.e. area covered by vegetation less than 20%), in some parameter domains, appears in bifurcation or multiequilibrium state. Meanwhile, in such area, ecosystem is extremely unstable. Any minor change to the balance will cause either increase or reduction of area covered by vegetation in ecosystem, on the basis of discussion on the emergency of these phenomena. This paper is attempting to propose an effective way of destruction and rebuilt ecosystem in transitional zone. The way is to control the evaporation of plant through selecting anti-drought country plant with big stomata resistance, and modify the roughness of the underlying surface in ecosystem by establishing rational interspace structure of plant community, so as to put the degenerative ecosystem into the natural succession track. This primary theory is being verified through observation and analysis on historical data.
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1981-05-01
drops at its lowest point to 154 meters below sea level and presents a varied natural panorama of desert, oasis, gorges and sand dunes. The chief...Febr’iarv each :ear AraiKawa. Ab’ . -. 25 Thermal conditions in the depression are similar to those in North China, but the amount of precipitation is
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NASA Technical Reports Server (NTRS)
2004-01-01
30 October 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows shallow tributary valleys in the Ismenius Lacus fretted terrain region of northern Arabia Terra. These valleys exhibit a variety of typical fretted terrain valley wall and floor textures, including a lineated, pitted material somewhat reminiscent of the surface of a brain. Origins for these features are still being debated within the Mars science community; there are no clear analogs to these landforms on Earth. This image is located near 39.9oN, 332.1oW. The picture covers an area about 3 km (1.9 mi) wide. Sunlight illuminates the scene from the lower left. -
Belcher, Wayne R.; Sweetkind, Donald S.; Faunt, Claudia C.; Pavelko, Michael T.; Hill, Mary C.
2017-01-19
Since the original publication of the Death Valley regional groundwater flow system (DVRFS) numerical model in 2004, more information on the regional groundwater flow system in the form of new data and interpretations has been compiled. Cooperators such as the Bureau of Land Management, National Park Service, U.S. Fish and Wildlife Service, the Department of Energy, and Nye County, Nevada, recognized a need to update the existing regional numerical model to maintain its viability as a groundwater management tool for regional stakeholders. The existing DVRFS numerical flow model was converted to MODFLOW-2005, updated with the latest available data, and recalibrated. Five main data sets were revised: (1) recharge from precipitation varying in time and space, (2) pumping data, (3) water-level observations, (4) an updated regional potentiometric map, and (5) a revision to the digital hydrogeologic framework model.The resulting DVRFS version 2.0 (v. 2.0) numerical flow model simulates groundwater flow conditions for the Death Valley region from 1913 to 2003 to correspond to the time frame for the most recently published (2008) water-use data. The DVRFS v 2.0 model was calibrated by using the Tikhonov regularization functionality in the parameter estimation and predictive uncertainty software PEST. In order to assess the accuracy of the numerical flow model in simulating regional flow, the fit of simulated to target values (consisting of hydraulic heads and flows, including evapotranspiration and spring discharge, flow across the model boundary, and interbasin flow; the regional water budget; values of parameter estimates; and sensitivities) was evaluated. This evaluation showed that DVRFS v. 2.0 simulates conditions similar to DVRFS v. 1.0. Comparisons of the target values with simulated values also indicate that they match reasonably well and in some cases (boundary flows and discharge) significantly better than in DVRFS v. 1.0.
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Earthquake processes in the Rainbow Mountain-Fairview Peak-Dixie Valley, Nevada, region 1954-1959
NASA Astrophysics Data System (ADS)
Doser, Diane I.
1986-11-01
The 1954 Rainbow Mountain-Fairview Peak-Dixie Valley, Nevada, sequence produced the most extensive pattern of surface faults in the intermountain region in historic time. Five earthquakes of M>6.0 occurred during the first 6 months of the sequence, including the December 16, 1954, Fairview Peak (M = 7.1) and Dixie Valley (M = 6.8) earthquakes. Three 5.5≤M≤6.5 earthquakes occurred in the region in 1959, but none exhibited surface faulting. The results of the modeling suggest that the M>6.5 earthquakes of this sequence are complex events best fit by multiple source-time functions. Although the observed surface displacements for the July and August 1954 events showed only dip-slip motion, the fault plane solutions and waveform modeling suggest the earthquakes had significant components of right-lateral strike-slip motion (rakes of -135° to -145°). All of the earthquakes occurred along high-angle faults with dips of 40° to 70°. Seismic moments for individual subevents of the sequence range from 8.0 × 1017 to 2.5 × 1019 N m. Stress drops for the subevents, including the Fairview Peak subevents, were between 0.7 and 6.0 MPa.
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Transport of regional pollutants through a remote trans-Himalayan valley in Nepal
NASA Astrophysics Data System (ADS)
Dhungel, Shradda; Kathayat, Bhogendra; Mahata, Khadak; Panday, Arnico
2018-01-01
Anthropogenic emissions from the combustion of fossil fuels and biomass in Asia have increased in recent years. High concentrations of reactive trace gases and light-absorbing and light-scattering particles from these sources form persistent haze layers, also known as atmospheric brown clouds, over the Indo-Gangetic plains (IGP) from December through early June. Models and satellite imagery suggest that strong wind systems within deep Himalayan valleys are major pathways by which pollutants from the IGP are transported to the higher Himalaya. However, observational evidence of the transport of polluted air masses through Himalayan valleys has been lacking to date. To evaluate this pathway, we measured black carbon (BC), ozone (O3), and associated meteorological conditions within the Kali Gandaki Valley (KGV), Nepal, from January 2013 to July 2015. BC and O3 varied over both diurnal and seasonal cycles. Relative to nighttime, mean BC and O3 concentrations within the valley were higher during daytime when the up-valley flow (average velocity of 17 m s-1) dominated. BC and O3 concentrations also varied seasonally with minima during the monsoon season (July to September). Concentrations of both species subsequently increased post-monsoon and peaked during March to May. Average concentrations for O3 during the seasonally representative months of April, August, and November were 41.7, 24.5, and 29.4 ppbv, respectively, while the corresponding BC concentrations were 1.17, 0.24, and 1.01 µg m-3, respectively. Up-valley fluxes of BC were significantly greater than down-valley fluxes during all seasons. In addition, frequent episodes of BC concentrations 2-3 times higher than average persisted from several days to a week during non-monsoon months. Our observations of increases in BC concentration and fluxes in the valley, particularly during pre-monsoon, provide evidence that trans-Himalayan valleys are important conduits for transport of pollutants from the IGP to the
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The Long Valley Caldera GIS database
Battaglia, Maurizio; Williams, M.J.; Venezky, D.Y.; Hill, D.P.; Langbein, J.O.; Farrar, C.D.; Howle, J.F.; Sneed, M.; Segall, P.
2003-01-01
This database provides an overview of the studies being conducted by the Long Valley Observatory in eastern California from 1975 to 2001. The database includes geologic, monitoring, and topographic datasets related to Long Valley caldera. The CD-ROM contains a scan of the original geologic map of the Long Valley region by R. Bailey. Real-time data of the current activity of the caldera (including earthquakes, ground deformation and the release of volcanic gas), information about volcanic hazards and the USGS response plan are available online at the Long Valley observatory web page (http://lvo.wr.usgs.gov). If you have any comments or questions about this database, please contact the Scientist in Charge of the Long Valley observatory.
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Polarization measurements made on LFRA and OASIS emitter arrays
NASA Astrophysics Data System (ADS)
Geske, Jon; Sparkman, Kevin; Oleson, Jim; Laveigne, Joe; Sieglinger, Breck; Marlow, Steve; Lowry, Heard; Burns, James
2008-04-01
Polarization is increasingly being considered as a method of discrimination in passive sensing applications. In this paper the degree of polarization of the thermal emission from the emitter arrays of two new Santa Barbara Infrared (SBIR) micro-bolometer resistor array scene projectors was characterized at ambient temperature and at 77 K. The emitter arrays characterized were from the Large Format Resistive Array (LFRA) and the Optimized Arrays for Space-Background Infrared Simulation (OASIS) scene projectors. This paper reports the results of this testing.
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DOT National Transportation Integrated Search
1998-11-01
The purpose of this study is to provide the framework for future implementation of Intelligent Transportation Systems (ITS) in the Lower Hudson Valley area. The focus of the planning study is the regional freeway system, major arterial routes and the...
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Geologic map of the upper Arkansas River valley region, north-central Colorado
Kellogg, Karl S.; Shroba, Ralph R.; Ruleman, Chester A.; Bohannon, Robert G.; McIntosh, William C.; Premo, Wayne R.; Cosca, Michael A.; Moscati, Richard J.; Brandt, Theodore R.
2017-11-17
This 1:50,000-scale U.S. Geological Survey geologic map represents a compilation of the most recent geologic studies of the upper Arkansas River valley between Leadville and Salida, Colorado. The valley is structurally controlled by an extensional fault system that forms part of the prominent northern Rio Grande rift, an intra-continental region of crustal extension. This report also incorporates new detailed geologic mapping of previously poorly understood areas within the map area and reinterprets previously studied areas. The mapped region extends into the Proterozoic metamorphic and intrusive rocks in the Sawatch Range west of the valley and the Mosquito Range to the east. Paleozoic rocks are preserved along the crest of the Mosquito Range, but most of them have been eroded from the Sawatch Range. Numerous new isotopic ages better constrain the timing of both Proterozoic intrusive events, Late Cretaceous to early Tertiary intrusive events, and Eocene and Miocene volcanic episodes, including widespread ignimbrite eruptions. The uranium-lead ages document extensive about 1,440-million years (Ma) granitic plutonism mostly north of Buena Vista that produced batholiths that intruded an older suite of about 1,760-Ma metamorphic rocks and about 1,700-Ma plutonic rocks. As a result of extension during the Neogene and possibly latest Paleogene, the graben underlying the valley is filled with thick basin-fill deposits (Dry Union Formation and older sediments), which occupy two sub-basins separated by a bedrock high near the town of Granite. The Dry Union Formation has undergone deep erosion since the late Miocene or early Pliocene. During the Pleistocene, ongoing steam incision by the Arkansas River and its major tributaries has been interrupted by periodic aggradation. From Leadville south to Salida as many as seven mapped alluvial depositional units, which range in age from early to late Pleistocene, record periodic aggradational events along these streams that are
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Blainey, Joan B.; Faunt, Claudia C.; Hill, Mary C.
2006-01-01
This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.
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NASA Astrophysics Data System (ADS)
Rebuffi, Luca; Sanchez del Rio, Manuel
2017-08-01
In the next years most of the major synchrotron radiation facilities around the world will upgrade to 4th-generation Diffraction Limited Storage Rings using multi-bend-achromat technology. Moreover, several Free Electron Lasers are ready-to-go or in phase of completion. These events represent a huge challenge for the optics physicists responsible of designing and calculating optical systems capable to exploit the revolutionary characteristics of the new photon beams. Reliable and robust beamline design is nowadays based on sophisticated computer simulations only possible by lumping together different simulation tools. The OASYS (OrAnge SYnchrotron Suite) suite drives several simulation tools providing new mechanisms of interoperability and communication within the same software environment. OASYS has been successfully used during the conceptual design of many beamline and optical designs for the ESRF and Elettra- Sincrotrone Trieste upgrades. Some examples are presented showing comparisons and benchmarking of simulations against calculated and experimental data.
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42 CFR 484.11 - Condition of participation: Release of patient identifiable OASIS information.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 5 2010-10-01 2010-10-01 false Condition of participation: Release of patient... Administration § 484.11 Condition of participation: Release of patient identifiable OASIS information. The HHA and agent acting on behalf of the HHA in accordance with a written contract must ensure the...
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21st Century jobs initiative - Tennessee`s Resource Valley. Progress report 1995
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-12-20
Tennessee`s Resource Valley, a regional economic development organization, was asked to facilitate a two-year, $750,000 grant from the Department of Energy. The grant`s purpose is to make the East Tennessee region less dependent on federal funds for its economic well-being and to increase regional awareness of the advantages of proximity to the Department of Energy facilities in Oak Ridge. Tennessee`s Resource Valley`s mission is to market the mid-East Tennessee region`s business location advantages to corporate decision makers and to facilitate regional initiatives that impact the creation of quality job opportunities. Tennessee`s Resource Valley represents the following fifteen (15) counties inmore » East Tennessee: Anderson, Blount, Campbell, Claiborne, Cocke, Grainger, Jefferson, Knox, Loudon, Monroe, Morgan, Scott, Sevier, and Union.« less
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The Health Valley: Global Entrepreneurial Dynamics.
Dubuis, Benoit
2014-12-01
In the space of a decade, the Lake Geneva region has become the Health Valley, a world-class laboratory for discovering and developing healthcare of the future. Through visionary individuals and thanks to exceptional infrastructure this region has become one of the most dynamic in the field of innovation, including leading scientific research and exceptional actors for the commercialization of academic innovation to industrial applications that will improve the lives of patients and their families. Here follows the chronicle of a spectacular expansion into the Health Valley.
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NASA Astrophysics Data System (ADS)
Messenzehl, Karoline; Meyer, Hanna; Otto, Jan-Christoph; Hoffmann, Thomas; Dikau, Richard
2017-06-01
In mountain geosystems, rockfalls are among the most effective sediment transfer processes, reflected in the regional-scale distribution of talus slopes. However, the understanding of the key controlling factors seems to decrease with increasing spatial scale, due to emergent and complex system behavior and not least to recent methodological shortcomings in rockfall modeling research. In this study, we aim (i) to develop a new approach to identify major regional-scale rockfall controls and (ii) to quantify the relative importance of these controls. Using a talus slope inventory in the Turtmann Valley (Swiss Alps), we applied for the first time the decision-tree based random forest algorithm (RF) in combination with a principal component logistic regression (PCLR) to evaluate the spatial distribution of rockfall activity. This study presents new insights into the discussion on whether periglacial rockfall events are controlled more by topo-climatic, cryospheric, paraglacial or/and rock mechanical properties. Both models explain the spatial rockfall pattern very well, given the high areas under the Receiver Operating Characteristic (ROC) curves of > 0.83. Highest accuracy was obtained by the RF, correctly predicting 88% of the rockfall source areas. The RF appears to have a great potential in geomorphic research involving multicollinear data. The regional permafrost distribution, coupled to the bedrock curvature and valley topography, was detected to be the primary rockfall control. Rockfall source areas cluster within a low-radiation elevation belt (2900-3300 m a.s.l,) consistent with a permafrost probability of > 90%. The second most important factor is the time since deglaciation, reflected by the high abundance of rockfalls along recently deglaciated (< 100 years), north-facing slopes. However, our findings also indicate a strong rock mechanical control on the paraglacial rockfall activity, declining either exponentially or linearly since deglaciation. The study
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Wanty, R.B.; Goldhaber, M.B.; Morrison, J.M.; Lee, L.
2009-01-01
Regional patterns in ground- and surface-water chemistry of the southern Sacramento Valley in California were evaluated using publicly available geochemical data from the US Geological Survey's National Water Information System (NWIS). Within the boundaries of the study area, more than 2300 ground-water analyses and more than 20,000 surface-water analyses were available. Ground-waters from the west side of the Sacramento Valley contain greater concentrations of Na, Ca, Mg, B, Cl and SO4, while the east-side ground-waters contain greater concentrations of silica and K. These differences result from variations in surface-water chemistry as well as from chemical reactions between water and aquifer materials. Sediments that fill the Sacramento Valley were derived from highlands to the west (the Coast Ranges) and east (the Sierra Nevada Mountains), the former having an oceanic provenance and the latter continental. These geologic differences are at least in part responsible for the observed patterns in ground-water chemistry. Thermal springs that are common along the west side of the Sacramento Valley appear to have an effect on surface-water chemistry, which in turn may affect the ground-water chemistry.
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Hou, Lan-Gong; Zou, Song-Bing; Xiao, Hong-Lang; Yang, Yong-Gang
2013-01-01
The standardized FAO56 Penman-Monteith model, which has been the most reasonable method in both humid and arid climatic conditions, provides reference evapotranspiration (ETo) estimates for planning and efficient use of agricultural water resources. And sensitivity analysis is important in understanding the relative importance of climatic variables to the variation of reference evapotranspiration. In this study, a non-dimensional relative sensitivity coefficient was employed to predict responses of ETo to perturbations of four climatic variables in the Ejina oasis northwest China. A 20-year historical dataset of daily air temperature, wind speed, relative humidity and daily sunshine duration in the Ejina oasis was used in the analysis. Results have shown that daily sensitivity coefficients exhibited large fluctuations during the growing season, and shortwave radiation was the most sensitive variable in general for the Ejina oasis, followed by air temperature, wind speed and relative humidity. According to this study, the response of ETo can be preferably predicted under perturbation of air temperature, wind speed, relative humidity and shortwave radiation by their sensitivity coefficients.
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2009-05-01
rates are low, ranging from 0.014 to 2.2 liters per second (0.22 to 35 gallons per minute) (IT, 1997; Thordarson and Robinson, 1971). Most water...Area Ash Meadows Discharge Area Oasis Valley Discharge Area 29 fractured volcanic rocks (Winograd and Thordarson , 1975; Laczniak et al., 1996...Vicinity The current understanding of regional groundwater flow at the subject property and adjacent NTS is derived from work by Winograd and Thordarson
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Hevesi, J.A.; Flint, A.L.; Flint, L.E.
2002-01-01
A three-dimensional ground-water flow model has been developed to evaluate the Death Valley regional flow system, which includes ground water beneath the Nevada Test Site. Estimates of spatially distributed net infiltration and recharge are needed to define upper boundary conditions. This study presents a preliminary application of a conceptual and numerical model of net infiltration. The model was developed in studies at Yucca Mountain, Nevada, which is located in the approximate center of the Death Valley ground-water flow system. The conceptual model describes the effects of precipitation, runoff, evapotranspiration, and redistribution of water in the shallow unsaturated zone on predicted rates of net infiltration; precipitation and soil depth are the two most significant variables. The conceptual model was tested using a preliminary numerical model based on energy- and water-balance calculations. Daily precipitation for 1980 through 1995, averaging 202 millimeters per year over the 39,556 square kilometers area of the ground-water flow model, was input to the numerical model to simulate net infiltration ranging from zero for a soil thickness greater than 6 meters to over 350 millimeters per year for thin soils at high elevations in the Spring Mountains overlying permeable bedrock. Estimated average net infiltration over the entire ground-water flow model domain is 7.8 millimeters per year.To evaluate the application of the net-infiltration model developed on a local scale at Yucca Mountain, to net-infiltration estimates representing the magnitude and distribution of recharge on a regional scale, the net-infiltration results were compared with recharge estimates obtained using empirical methods. Comparison of model results with previous estimates of basinwide recharge suggests that the net-infiltration estimates obtained using this model may overestimate recharge because of uncertainty in modeled precipitation, bedrock permeability, and soil properties for
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Hill, M.C.; D'Agnese, F. A.; Faunt, C.C.
2000-01-01
Fourteen guidelines are described which are intended to produce calibrated groundwater models likely to represent the associated real systems more accurately than typically used methods. The 14 guidelines are discussed in the context of the calibration of a regional groundwater flow model of the Death Valley region in the southwestern United States. This groundwater flow system contains two sites of national significance from which the subsurface transport of contaminants could be or is of concern: Yucca Mountain, which is the potential site of the United States high-level nuclear-waste disposal; and the Nevada Test Site, which contains a number of underground nuclear-testing locations. This application of the guidelines demonstrates how they may be used for model calibration and evaluation, and also to direct further model development and data collection.Fourteen guidelines are described which are intended to produce calibrated groundwater models likely to represent the associated real systems more accurately than typically used methods. The 14 guidelines are discussed in the context of the calibration of a regional groundwater flow model of the Death Valley region in the southwestern United States. This groundwater flow system contains two sites of national significance from which the subsurface transport of contaminants could be or is of concern: Yucca Mountain, which is the potential site of the United States high-level nuclear-waste disposal; and the Nevada Test Site, which contains a number of underground nuclear-testing locations. This application of the guidelines demonstrates how they may be used for model calibration and evaluation, and also to direct further model development and data collection.
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D'Agnese, Frank A.; O'Brien, G. M.; Faunt, C.C.; Belcher, W.R.; San Juan, C.
2002-01-01
In the early 1990's, two numerical models of the Death Valley regional ground-water flow system were developed by the U.S. Department of Energy. In general, the two models were based on the same basic hydrogeologic data set. In 1998, the U.S. Department of Energy requested that the U.S. Geological Survey develop and maintain a ground-water flow model of the Death Valley region in support of U.S. Department of Energy programs at the Nevada Test Site. The purpose of developing this 'second-generation' regional model was to enhance the knowledge an understanding of the ground-water flow system as new information and tools are developed. The U.S. Geological Survey also was encouraged by the U.S. Department of Energy to cooperate to the fullest extent with other Federal, State, and local entities in the region to take advantage of the benefits of their knowledge and expertise. The short-term objective of the Death Valley regional ground-water flow system project was to develop a steady-state representation of the predevelopment conditions of the ground-water flow system utilizing the two geologic interpretations used to develop the previous numerical models. The long-term objective of this project was to construct and calibrate a transient model that simulates the ground-water conditions of the study area over the historical record that utilizes a newly interpreted hydrogeologic conceptual model. This report describes the result of the predevelopment steady-state model construction and calibration. The Death Valley regional ground-water flow system is situated within the southern Great Basin, a subprovince of the Basin and Range physiographic province, bounded by latitudes 35 degrees north and 38 degrees 15 minutes north and by longitudes 115 and 118 degrees west. Hydrology in the region is a result of both the arid climatic conditions and the complex geology. Ground-water flow generally can be described as dominated by interbasinal flow and may be conceptualized as
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Hevesi, Joseph A.; Flint, Alan L.; Flint, Lorraine E.
2003-01-01
This report presents the development and application of the distributed-parameter watershed model, INFILv3, for estimating the temporal and spatial distribution of net infiltration and potential recharge in the Death Valley region, Nevada and California. The estimates of net infiltration quantify the downward drainage of water across the lower boundary of the root zone and are used to indicate potential recharge under variable climate conditions and drainage basin characteristics. Spatial variability in recharge in the Death Valley region likely is high owing to large differences in precipitation, potential evapotranspiration, bedrock permeability, soil thickness, vegetation characteristics, and contributions to recharge along active stream channels. The quantity and spatial distribution of recharge representing the effects of variable climatic conditions and drainage basin characteristics on recharge are needed to reduce uncertainty in modeling ground-water flow. The U.S. Geological Survey, in cooperation with the Department of Energy, developed a regional saturated-zone ground-water flow model of the Death Valley regional ground-water flow system to help evaluate the current hydrogeologic system and the potential effects of natural or human-induced changes. Although previous estimates of recharge have been made for most areas of the Death Valley region, including the area defined by the boundary of the Death Valley regional ground-water flow system, the uncertainty of these estimates is high, and the spatial and temporal variability of the recharge in these basins has not been quantified. To estimate the magnitude and distribution of potential recharge in response to variable climate and spatially varying drainage basin characteristics, the INFILv3 model uses a daily water-balance model of the root zone with a primarily deterministic representation of the processes controlling net infiltration and potential recharge. The daily water balance includes precipitation
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Burow, Karen R.; Jurgens, Bryant C.; Belitz, Kenneth; Dubrovsky, Neil M.
2013-01-01
A regional assessment of multi-decadal changes in nitrate concentrations was done using historical data and a spatially stratified non-biased approach. Data were stratified into physiographic subregions on the basis of geomorphology and soils data to represent zones of historical recharge and discharge patterns in the basin. Data were also stratified by depth to represent a shallow zone generally representing domestic drinking-water supplies and a deep zone generally representing public drinking-water supplies. These stratifications were designed to characterize the regional extent of groundwater with common redox and age characteristics, two factors expected to influence changes in nitrate concentrations over time. Overall, increasing trends in nitrate concentrations and the proportion of nitrate concentrations above 5 mg/L were observed in the east fans subregion of the Central Valley. Whereas the west fans subregion has elevated nitrate concentrations, temporal trends were not detected, likely due to the heterogeneous nature of the water quality in this area and geologic sources of nitrate, combined with sparse and uneven data coverage. Generally low nitrate concentrations in the basin subregion are consistent with reduced geochemical conditions resulting from low permeability soils and higher organic content, reflecting the distal portions of alluvial fans and historical groundwater discharge areas. Very small increases in the shallow aquifer in the basin subregion may reflect downgradient movement of high nitrate groundwater from adjacent areas or overlying intensive agricultural inputs. Because of the general lack of regionally extensive long-term monitoring networks, the results from this study highlight the importance of placing studies of trends in water quality into regional context. Earlier work concluded that nitrate concentrations were steadily increasing over time in the eastern San Joaquin Valley, but clearly those trends do not apply to other
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NASA Astrophysics Data System (ADS)
Chacko, R.; Hammond, W. C.; Blewitt, G.; Bormann, J. M.
2014-12-01
Accurate estimates of fault slip rates based on geodetic data rely on measurements that represent the long-term deformation of the crust. In the Central Walker Lane/Sierra Nevada transition, the Long Valley Caldera region has experienced multiple episodes of uplift and subsidence during the last four decades. The latest episode began in late 2011 and is detectable as a transient signal in the time series of GPS stations around the caldera. These transient signals become more apparent and reveal the extent of the impact on the ambient crustal deformation field of the Walker Lane when the velocity vectors are transformed to a Sierra-Nevada reference frame. Estimating contemporary slip-rates on faults for the purpose of seismic hazard assessment in the region around Long Valley requires detecting and subtracting the transient signals caused by the uplift and subsidence in the caldera. We estimate the geographic extent to which the ambient crustal deformation field is significantly perturbed by ongoing magmatic activity in Long Valley. We present a time variable 3D deformation field constrained by InSAR and GPS observations, and discuss the implications that tectonic-magmatic interaction have for estimates of present-day fault slip-rate. We model the time dependent deformation at Long Valley by analyzing InSAR time series from Envisat and ERS interferograms spanning a period of more than 19 years. We use an analytical volcano deformation source model derived from vertical (GPS) and line of site (InSAR) component of geodetic observations to estimate the horizontal component of the signals associated with magmatic activity beneath the caldera. Previous studies showed that the latest episode of uplift can be modeled with a Mogi source located at a depth of ~6 km with a volume change of 0.03 km3 beneath the resurgent dome. This model predicts a perturbation to the ambient crustal deformation field extending as far as 60 km from the center of the resurgent dome. Thus the
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Valley-symmetric quasi-1D transport in ballistic graphene
NASA Astrophysics Data System (ADS)
Lee, Hu-Jong
We present our recent studies on gate-defined valley-symmetric one-dimensional (1D) carrier guiding in ballistic monolayer graphene and valley-symmetry-protected topological 1D transport in ballistic bilayer graphene. Successful carrier guiding was realized in ballistic monolayer graphene even in the absence of a band gap by inducing a high distinction ( more than two orders of magnitude) in the carrier density between the region of a quasi-1D channel and the rest of the top-gated regions. Conductance of a channel shows quantized values in units of 4e2/ h, suggesting that the valley symmetry is preserved. For the latter, the topological 1D conduction was realized between two closely arranged insulating regions with inverted band gaps, induced under a pair of split dual gating with polarities opposite to each other. The maximum conductance along the boundary channel showed 4e2/ h, again with the preserved valley symmetry. The 1D topological carrier guiding demonstrated in this study affords a promising route to robust valleytronic applications and sophisticated valley-associated functionalities based on 2D materials. This work was funded by the National Research Foundation of Korea.
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Knickpoints and Hanging Valleys of Licus Vallis, Mars
NASA Astrophysics Data System (ADS)
Goudge, T. A.; Fassett, C.
2016-12-01
Licus Vallis is a 350 km long valley system located along the dichotomy boundary on Mars. The main trunk of the valley is incised 200-700 m into the surrounding terrain. The valley heads at an outlet breach of a shallow, 30 km diameter impact crater, and is also fed by a system of tributaries incised into the plateau surrounding Licus Vallis. Many of the tributary valleys, as well as the main stem of the valley fed by the paleolake outlet, have profiles that are not smoothly graded, but rather have distinct reaches with concave downward topography. These sections are either knickpoints or hanging valleys that develop in response to changes in the effective local base level, changes in climate conditions during incision of the valley, or lithologic boundaries in the substrate. Here we present remote sensing observations from images and topography to test these competing hypotheses and further characterize the evolution of this large valley system. Slope-watershed area relationships for the tributaries and main trunk valley are used to distinguish between knickpoints and hanging valleys. Analysis of orbital images does not reveal any distinct layer above which knickpoints develop, and the elevation of knickpoints show no systematic trends that might be expected of a regional lithologic unit(s). Our preliminary results suggest that the distance of knickpoint retreat is correlated with the position of the tributary valley and not the watershed area. Downstream valleys have retreated the most, suggesting they have had the most time to adjust to lowering of the local base level associated with incision of the main valley. These results are most consistent with a wave of incision sweeping up the valley system as it adjusts to a low base level in the northern plains. This conclusion is also consistent with observations of the incision depth of Licus Vallis, which increases approximately linearly downstream. Understanding this signature of base level control on the incision
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OASIS Observation and Analysis of Smectic Islands in Space
NASA Technical Reports Server (NTRS)
Tin, Padetha
2014-01-01
The Observation and Analysis of Smectic Islands in Space (OASIS) project comprises a series of experiments that will probe the interfacial and hydrodynamic behavior of freely suspended liquid crystal films in space. These are the thinnest known stable condensed phase structures, making them ideal for studies of fluctuation and interface phenomena. The experiments seek to verify theories of coarsening dynamics, hydrodynamic flow, relaxation of hydrodynamic perturbations, and hydrodynamic interactions of a near two-dimensional structure. The effects of introducing islands or droplets on a very thin bubble will be studied, both as controllable inclusions that modify the flow and as markers of flow.
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Hao, Yuanyuan; Xie, Yaowen; Ma, Jinhui; Zhang, Wenpei
2017-12-01
Designed as a watershed groundwater restoration policy (WGRP), the Comprehensive Treatment Program of the Shiyang River Basin (CTSRB) was launched in 2006 to restore the groundwater resources in the Minqin oasis, northwestern China. This study sought to verify the recovery effects of CTSRB implementation from the perspective of groundwater depth. We reconstructed the spatio-temporal distribution of groundwater depth at interannual and pixel scales by using digital groundwater depth models (DGDMs), based on the ordinary kriging interpolation method. Using DGDMs data, various measures of the groundwater table (e.g., regional depths, surface areas, depletion cones, and conditions in irrigated regions including Ba, Quanshan, and Hu) were quantitatively analyzed and compared for the pre-CTSRB (2001-2006), CTSRB I (2006-2010), and CTSRB II (2010-2015) periods, for which spatial trends in the annual amplitudes of groundwater depth were compared. Finally, strategies that impacted the groundwater behavior before and during the CTSRB periods, possible indirect and adverse effects, and long-term strategies and prospects were discussed. The results showed that groundwater depth first declined sharply, before increasing slowly and stabilizing after implementation of the CTSRB. Areas of greater groundwater depth (<-20m) and four groundwater depletion cones expanded during the pre-CTSRB period, whereas variable shrinking trends were detected during the CTSRB period. Spatial analysis showed that groundwater recovery mainly occurred along the periphery of the three irrigated regions, among which recovery effects in Hu were more obvious than those in Quanshan and Ba, with pumping-well densities the main reason for the difference. Therefore, various strategies (increasing the surface water supply, reducing groundwater mining, and some other auxiliary measures) of CTSRB together supported groundwater recovery in the Minqin oasis. Overall, this research demonstrates an innovative
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Sork, Victoria L.; Davis, Frank W.; Westfall, Robert; Flint, Alan L.; Ikegami, Makihiko; Wang, Hongfang; Grivet, Delphine
2010-01-01
Rapid climate change jeopardizes tree populations by shifting current climate zones. To avoid extinction, tree populations must tolerate, adapt, or migrate. Here we investigate geographic patterns of genetic variation in valley oak, Quercus lobata N??e, to assess how underlying genetic structure of populations might influence this species' ability to survive climate change. First, to understand how genetic lineages shape spatial genetic patterns, we examine historical patterns of colonization. Second, we examine the correlation between multivariate nuclear genetic variation and climatic variation. Third, to illustrate how geographic genetic variation could interact with regional patterns of 21st Century climate change, we produce region-specific bioclimatic distributions of valley oak using Maximum Entropy (MAXENT) models based on downscaled historical (1971-2000) and future (2070-2100) climate grids. Future climatologies are based on a moderate-high (A2) carbon emission scenario and two different global climate models. Chloroplast markers indicate historical range-wide connectivity via colonization, especially in the north. Multivariate nuclear genotypes show a strong association with climate variation that provides opportunity for local adaptation to the conditions within their climatic envelope. Comparison of regional current and projected patterns of climate suitability indicates that valley oaks grow in distinctly different climate conditions in different parts of their range. Our models predict widely different regional outcomes from local displacement of a few kilometres to hundreds of kilometres. We conclude that the relative importance of migration, adaptation, and tolerance are likely to vary widely for populations among regions, and that late 21st Century conditions could lead to regional extinctions. ?? 2010 Blackwell Publishing Ltd.
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Sork, Victoria L; Davis, Frank W; Westfall, Robert; Flint, Alan; Ikegami, Makihiko; Wang, Hongfang; Grivet, Delphine
2010-09-01
Rapid climate change jeopardizes tree populations by shifting current climate zones. To avoid extinction, tree populations must tolerate, adapt, or migrate. Here we investigate geographic patterns of genetic variation in valley oak, Quercus lobata Née, to assess how underlying genetic structure of populations might influence this species' ability to survive climate change. First, to understand how genetic lineages shape spatial genetic patterns, we examine historical patterns of colonization. Second, we examine the correlation between multivariate nuclear genetic variation and climatic variation. Third, to illustrate how geographic genetic variation could interact with regional patterns of 21st Century climate change, we produce region-specific bioclimatic distributions of valley oak using Maximum Entropy (MAXENT) models based on downscaled historical (1971-2000) and future (2070-2100) climate grids. Future climatologies are based on a moderate-high (A2) carbon emission scenario and two different global climate models. Chloroplast markers indicate historical range-wide connectivity via colonization, especially in the north. Multivariate nuclear genotypes show a strong association with climate variation that provides opportunity for local adaptation to the conditions within their climatic envelope. Comparison of regional current and projected patterns of climate suitability indicates that valley oaks grow in distinctly different climate conditions in different parts of their range. Our models predict widely different regional outcomes from local displacement of a few kilometres to hundreds of kilometres. We conclude that the relative importance of migration, adaptation, and tolerance are likely to vary widely for populations among regions, and that late 21st Century conditions could lead to regional extinctions.
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Norman, Sonya B.; Campbell-Sills, Laura; Hitchcock, Carla A.; Sullivan, Sarah; Rochlin, Alexis; Wilkins, Kendall C.; Stein, Murray B.
2010-01-01
Brief measures of anxiety related severity and impairment that can be used across anxiety disorders and with subsyndromal anxiety are lacking. The Overall Anxiety Severity and Impairment Scale (OASIS) have shown strong psychometric properties with college students and primary care patients. This study examines sensitivity, specificity, and efficiency of an abbreviated version of the OASIS that takes only 2–3 minutes to complete using a non-clinical (college student) sample. 48 participants completed the OASIS and SCID for anxiety disorders, 21 had a diagnosis of ≥1 anxiety disorder, and 4 additional participants had a subthreshold diagnosis. A cut-score of 8 best discriminated those with anxiety disorders from those without, successfully classifying 78% of the sample with 69% sensitivity and 74% specificity. Results from a larger sample (n=171) showed a single factor structure and excellent convergent and divergent validity. The availability of cut-scores for a non-clinical sample furthers the utility of this measure for settings where screening or brief assessment of anxiety is needed. PMID:20609450
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42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...
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42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.
Code of Federal Regulations, 2011 CFR
2011-10-01
...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...
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42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...
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42 CFR 488.68 - State Agency responsibilities for OASIS collection and data base requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
...— (1) Instruct each HHA on the administration of the data set, privacy/confidentiality of the data set, and integration of the OASIS data set into the facility's own record keeping system; (2) Instruct each... and data base requirements. 488.68 Section 488.68 Public Health CENTERS FOR MEDICARE & MEDICAID...
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Trypanosoma mega (Kinetoplastida) from Bufo viridis in Siwah Oasis, Egypt.
Ashour, A A; Gaafar, N A
1997-04-01
A large pleomorphic trypanosome, identified as Trypanosoma mega, is described from the toad Bufo viridis collected from Siwah Oasis at the Western Desert of Egypt. The prevalence of the trypanosome is 83.3%. Three trypanosome forms are described, small, intermediate and large stumpy form. Observations were also made on the lysed (diffused) trypanosomes. This is the first record of T. mega from B. viridis in Egypt which represents a new host and new geographical location. The measurements of the present trypanosome are given and compared with related forms previously described from Egypt.
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A Quantitative Analysis of the Fretted Terrain Valleys, Arabia Terra, Mars
NASA Astrophysics Data System (ADS)
Mason, Kelsey Anne
Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypothesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, valley geometries and orientations throughout the fretted terrain, this study better constrains the origin of the valleys. Valleys were mapped using automated routines in ArcGIS including the D8 flow direction algorithm. Valleys were then grouped geographically into basins and also by Strahler order. The valleys were then segmented every 50 km and the azimuth of each segment was calculated. The resulting valley azimuths were analyzed using rose diagrams to quantitatively describe the planform geometries of the valleys. Qualitatively, the majority of basins were found to have rectangular valley geometries. The downslope direction was calculated for each basin, and it was compared to the corresponding valley azimuths. The basins with rectangular valley geometries had valleys with an azimuth mode nearly parallel to the downslope direction and another azimuth mode perpendicular to the downslope direction. The valley azimuth mode parallel to the downslope direction is attributed to hydrological flow processes while the mode perpendicular to the downslope direction is attributed to fracturing related to the formation or existence of the Mars global dichotomy boundary.
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[Spatial differentiation and impact factors of Yutian Oasis's soil surface salt based on GWR model].
Yuan, Yu Yun; Wahap, Halik; Guan, Jing Yun; Lu, Long Hui; Zhang, Qin Qin
2016-10-01
In this paper, topsoil salinity data gathered from 24 sampling sites in the Yutian Oasis were used, nine different kinds of environmental variables closely related to soil salinity were selec-ted as influencing factors, then, the spatial distribution characteristics of topsoil salinity and spatial heterogeneity of influencing factors were analyzed by combining the spatial autocorrelation with traditional regression analysis and geographically weighted regression model. Results showed that the topsoil salinity in Yutian Oasis was not of random distribution but had strong spatial dependence, and the spatial autocorrelation index for topsoil salinity was 0.479. Groundwater salinity, groundwater depth, elevation and temperature were the main factors influencing topsoil salt accumulation in arid land oases and they were spatially heterogeneous. The nine selected environmental variables except soil pH had significant influences on topsoil salinity with spatial disparity. GWR model was superior to the OLS model on interpretation and estimation of spatial non-stationary data, also had a remarkable advantage in visualization of modeling parameters.
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NASA Astrophysics Data System (ADS)
Mergelov, N. S.
2014-09-01
The properties and spatial distribution of soils and soil-like bodies in valleys of the coastal Larsemann Hills and Vestfold Hills oases—poorly investigated in terms of the soil areas of East Antarctica—are discussed. In contrast to Dry Valleys—large continental oases of Western Antarctica—the studied territory is characterized by the presence of temporarily waterlogged sites in the valleys. It is argued that the deficit of water rather than the low temperature is the major limiting factor for the development of living organisms and the pedogenesis on loose substrates. The moisture gradients in the surface soil horizons explain the spatial distribution of the different soils and biotic complexes within the studied valleys. Despite the permanent water-logging of the deep suprapermafrost horizons of most of the soils in the valleys, no gley features have been identified in them. The soils of the wet valleys in the Larsemann Hills oasis do not contain carbonates. They have a slightly acid or neutral reaction. The organic carbon and nitrogen contents are mainly controlled by the amount of living and dead biomass rather than by the humic substances proper. The larger part of the biomass is concentrated inside the mineral soil matrix rather than on the soil surface. The stresses caused by surface drying, strong winds, and ultraviolet radiation prevent the development of organisms on the surface of the soil and necessitate the search for shelter within the soil fine earth material (endoedaphic niche) or under the gravelly pavement (hypolithic niche). In the absence of higher plants, humified products of their decomposition, and rainwater that can wash the soil profile and upon the low content of silt and clay particles in the soil material, "classical" soil horizons are not developed. The most distinct (and, often, the only diagnosed) products of pedogenesis in these soils are represented by organomineral films on the surface of mineral particles.
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NASA Astrophysics Data System (ADS)
Faloona, I. C.; Conley, S. A.; Caputi, D.; Trousdell, J.; Chiao, S.; Eiserloh, A. J., Jr.; Clark, J.; Iraci, L. T.; Yates, E. L.; Marrero, J. E.; Ryoo, J. M.; McNamara, M. E.
2016-12-01
The San Joaquin Valley of California is wide ( 75 km) and long ( 400 km), and is situated under strong atmospheric subsidence due, in part, to the proximity of the midlatitude anticyclone of the Pacific High. The capping effect of this subsidence is especially prominent during the warm season when ground level ozone is a serious air quality concern across the region. While relatively clean marine boundary layer air is primarily funneled into the valley below the strong subsidence inversion at significant gaps in the upwind Coast Range mountains, airflow aloft also spills over these barriers and mixes into the valley from above. Because this transmountain flow occurs under the influence of synoptic subsidence it tends to present discrete, laminar sheets of differing air composition above the valley boundary layer. Meanwhile, although the boundary layers tend to remain shallow due to the prevailing subsidence, orographic and anabatic venting of valley boundary layer air around the basin whips up a complex admixture of regional air masses into a "buffer layer" just above the boundary layer (zi) and below the lower free troposphere. We present scalar data of widely varying lifetimes including ozone, methane, NOx, and thermodynamic observations from upwind and within the San Joaquin Valley to better explain this layering and its subsequent erosion into the valley boundary layer via entrainment. Data collected at a mountaintop monitoring station on Chews Ridge in the Coast Range, by coastal ozonesondes, and aircraft are analyzed to document the dynamic layering processes around the complex terrain surrounding the valley. Particular emphasis will be made on observational methods whereby distal ozone can be distinguished from the regional ozone to better understand the influence of exogenous sources on air quality in the valley.
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Air flow analysis in the upper Río Negro Valley (Argentina)
NASA Astrophysics Data System (ADS)
Cogliati, M. G.; Mazzeo, N. A.
2006-06-01
The so called Upper Río Negro Valley in Argentina is one of the most important fruit and vegetable production regions of the country. It comprises the lower valleys of the Limay and Neuquén rivers and the upper Negro river valley. Out of the 41,671 cultivated hectares, 84.6% are cultivated with fruit trees, especially apple, pear and stone fruit trees. Late frosts occurring when trees are sensitive to low temperatures have a significant impact on the regional production. This study presents an analysis of air flow characteristics in the Upper Río Negro Valley and its relationship with ambient air flow. To such effect, observations made when synoptic-scale weather patterns were favorable for radiative frosts (light wind and clear sky) or nocturnal temperature inversion in the lower layer were used. In the Negro river valley, both wind channeling and downward horizontal momentum transport from ambient wind were observed; in nighttime, very light wind events occurred, possibly associated with drainage winds from the nearby higher levels of the barda. In the Neuquén river valley, the prevailing effect appeared to be forced channeling, consistent with the results obtained in valleys where the synoptic scale wind crossed the axis of the valley. In the Limay river valley, the flow was observed to blow parallel to the longitudinal valley axis, possibly influenced by pressure gradient and forced channeling.
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The McMurdo Dry Valleys: A landscape on the threshold of change
NASA Astrophysics Data System (ADS)
Fountain, Andrew G.; Levy, Joseph S.; Gooseff, Michael N.; Van Horn, David
2014-11-01
Field observations of coastal and lowland regions in the McMurdo Dry Valleys suggest they are on the threshold of rapid topographic change, in contrast to the high elevation upland landscape that represents some of the lowest rates of surface change on Earth. A number of landscapes have undergone dramatic and unprecedented landscape changes over the past decade including, the Wright Lower Glacier (Wright Valley) - ablated several tens of meters, the Garwood River (Garwood Valley) has incised > 3 m into massive ice permafrost, smaller streams in Taylor Valley (Crescent, Lawson, and Lost Seal Streams) have experienced extensive down-cutting and/or bank undercutting, and Canada Glacier (Taylor Valley) has formed sheer, > 4 meter deep canyons. The commonality between all these landscape changes appears to be sediment on ice acting as a catalyst for melting, including ice-cement permafrost thaw. We attribute these changes to increasing solar radiation over the past decade despite no significant trend in summer air temperature. To infer possible future landscape changes in the McMurdo Dry Valleys, due to anticipated climate warming, we map ‘at risk’ landscapes defined as those with buried massive ice in relative warm regions of the valleys. Results show that large regions of the valley bottoms are ‘at risk’. Changes in surface topography will trigger important responses in hydrology, geochemistry, and biological community structure and function.
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Geologic history of the Yosemite Valley
Matthes, Francois E.
1930-01-01
Projection of the longitudinal profiles of these hanging valleys forward to the axis of the Merced Canyon shows that they are closely accordant in height. Their profiles indicate a series of points on a former profile of the Merced with respect to which the side streams had graded their courses prior to the last uplift. This old profile can be extended upward into the glaciated part of the Merced Canyon above El Portal and even into the profoundly glaciated Yosemite Valley, accordant points being furnished by a number of hanging side valleys (due allowance being made for glacial erosion suffered by those valleys). However, not all the hanging valleys of the Yosemite region are accordant with this set. Several of them, including the upland valley of Yosemite Creek, constitute a separate set indicating another old profile of the Merced at a level 600 to 1,000 feet higher than the first. Others, including the hanging gulch of lower Bridalveil Creek, point to an old profile of the Merced about 1,200 feet lower than the first. There are thus three distinct sets of hanging valleys produced in three cycles of stream erosion. The valleys of the upper set, like those of the middle set, were left hanging as a result of rapid trenching by the Merced induced by an uplift of the range, there having been two such uplifts. Only the valleys of the lower set hang because of glacial deepening and widening of the Yosemite Valley, the cycle in which they were cut having been interrupted by the advent of the Pleistocene glaciers. They consequently indicate the preglacial depth of the Yosemite Valley. That depth, measured from the brow of El Capitan, was about 2,400 feet; measured from the rim at Glacier Point it was about 2,000 feet.
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Belcher, Wayne R.; Sweetkind, Donald S.
2010-01-01
A numerical three-dimensional (3D) transient groundwater flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the groundwater flow system and previous less extensive groundwater flow models were incorporated and reevaluated together with new data to provide greater detail for the complex, digital model. A 3D digital hydrogeologic framework model (HFM) was developed from digital elevation models, geologic maps, borehole information, geologic and hydrogeologic cross sections, and other 3D models to represent the geometry of the hydrogeologic units (HGUs). Structural features, such as faults and fractures, that affect groundwater flow also were added. The HFM represents Precambrian and Paleozoic crystalline and sedimentary rocks, Mesozoic sedimentary rocks, Mesozoic to Cenozoic intrusive rocks, Cenozoic volcanic tuffs and lavas, and late Cenozoic sedimentary deposits of the Death Valley regional groundwater flow system (DVRFS) region in 27 HGUs. Information from a series of investigations was compiled to conceptualize and quantify hydrologic components of the groundwater flow system within the DVRFS model domain and to provide hydraulic-property and head-observation data used in the calibration of the transient-flow model. These studies reevaluated natural groundwater discharge occurring through evapotranspiration (ET) and spring flow; the history of groundwater pumping from 1913 through 1998; groundwater recharge simulated as net infiltration; model boundary inflows and outflows based on regional hydraulic gradients and water budgets of surrounding areas; hydraulic conductivity and its relation to depth; and water levels appropriate for regional simulation of prepumped and pumped conditions within the DVRFS model domain. Simulation results appropriate for the regional extent and scale of the model were provided
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Moreo, Michael T.; Justet, Leigh
2008-01-01
Ground-water withdrawal estimates from 1913 through 2003 for the Death Valley regional ground-water flow system are compiled in an electronic database to support a regional, three-dimensional, transient ground-water flow model. This database updates a previously published database that compiled estimates of ground-water withdrawals for 1913-1998. The same methodology is used to construct each database. Primary differences between the 2 databases are an additional 5 years of ground-water withdrawal data, well locations in the updated database are restricted to Death Valley regional ground-water flow system model boundary, and application rates are from 0 to 1.5 feet per year lower than original estimates. The lower application rates result from revised estimates of crop consumptive use, which are based on updated estimates of potential evapotranspiration. In 2003, about 55,700 acre-feet of ground water was pumped in the DVRFS, of which 69 percent was used for irrigation, 13 percent for domestic, and 18 percent for public supply, commercial, and mining activities.
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Norman, Sonya B; Allard, Carolyn B; Trim, Ryan S; Thorp, Steven R; Behrooznia, Michelle; Masino, Tonya T; Stein, Murray B
2013-04-01
Many women have unidentified anxiety or trauma histories that can impact their health and medical treatment-seeking behavior. This study examined the sensitivity, specificity, efficiency, and sensitivity to change of the Overall Anxiety Severity and Impairment Scale (OASIS) for identifying an anxiety disorder in a female sample with and without trauma history related to intimate partner violence (IPV). Forty-three women with full or partial PTSD from IPV and 41 women without PTSD completed the OASIS. All participants with trauma history completed the Clinician Administered PTSD Scale. This report is a secondary analysis of a study on the neurobiology of psychological trauma in survivors of IPV recruited from the community. A cut-score of 5 best discriminated those with PTSD from those without, successfully classifying 91% of the sample with 93% sensitivity and 90% specificity. The measure showed strong sensitivity to change in a subsample of 20 participants who completed PTSD treatment and strong convergent and divergent validity in the full sample. This study suggests that the OASIS can identify the presence of an anxiety disorder among a female sample of IPV survivors when PTSD is present.
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NASA Astrophysics Data System (ADS)
Li, Xianwen; Jin, Menggui; Zhou, Nianqing; Huang, Jinou; Jiang, Simin; Telesphore, Habiyakare
2016-07-01
Mulched drip irrigation for cotton field is an effective measure for the utilization of saline water, and the regulation of soil water and salt. However, the reasonable methods for quantifying actual evapotranspiration (ET) and deep percolation of recharge to groundwater are still not very well understood, which restricts the accurate regulation of soil water and salt for cotton growth in oasis. In this paper, a set of experiments of mulched drip irrigation with brackish water were conducted in a typical arid region of Tarim basin in southern Xinjiang, China. The irrigation events were recorded, and ET and fluctuations of groundwater table were carefully measured for two consecutive irrigation periods of flowering and bolling stages. A group of upscaling conversion methods were used to quantify the ET, in which canopy structure was considered to estimate the transpiration from leaf scale to a unit of field scale. The groundwater table had a significant response to the irrigation events, thus the deep percolation was estimated using water-table fluctuation method (WTF). Results showed that during the two irrigation events of flowering and bolling stages, the total ET was 31.1 mm with the soil surface evaporation of only 0.4 mm. The total percolation of recharge to groundwater was 48.2 mm which contributed to the groundwater run-off of 22.1 mm. Transpiration of 30.7 mm accounted for 98.6% of the total ET of 31.1 mm and 34.3% of the irrigation water of 90.6 mm. Compared with transpiration, the deep percolation accounted for 53.2% of irrigation water, indicating a serious excessive irrigation that recharged to groundwater. Soil salt budget showed that the salt leached into groundwater was 1.56 times of the input from brackish irrigation water and fertilization during the two irrigation periods. Even for the irrigation practice with brackish water, the accumulated salt of soil profile could also be leached out under large amount of irrigation water (e.g. 90.6 mm for the
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NASA Astrophysics Data System (ADS)
Hu, X.; Li, X.; Lu, L.
2017-12-01
Land use/cover change (LUCC) is an important subject in the research of global environmental change and sustainable development, while spatial simulation on land use/cover change is one of the key content of LUCC and is also difficult due to the complexity of the system. The cellular automata (CA) model had an irreplaceable role in simulating of land use/cover change process due to the powerful spatial computing power. However, the majority of current CA land use/cover models were binary-state model that could not provide more general information about the overall spatial pattern of land use/cover change. Here, a multi-state logistic-regression-based Markov cellular automata (MLRMCA) model and a multi-state artificial-neural-network-based Markov cellular automata (MANNMCA) model were developed and were used to simulate complex land use/cover evolutionary process in an arid region oasis city constrained by water resource and environmental policy change, the Zhangye city during the period of 1990-2010. The results indicated that the MANNMCA model was superior to MLRMCA model in simulated accuracy. These indicated that by combining the artificial neural network with CA could more effectively capture the complex relationships between the land use/cover change and a set of spatial variables. Although the MLRMCA model were also some advantages, the MANNMCA model was more appropriate for simulating complex land use/cover dynamics. The two proposed models were effective and reliable, and could reflect the spatial evolution of regional land use/cover changes. These have also potential implications for the impact assessment of water resources, ecological restoration, and the sustainable urban development in arid areas.
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ERIC Educational Resources Information Center
Tennessee Valley Authority, Knoxville.
This syllabus outlines a course of study in integrated regional resources management based on the experience of the Tennessee Valley Authority (TVA). The course has been developed for resource practitioners, in developing countries, who have responsibilities related to topics addressed in the course's 14 instructional modules. These topics are:…
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Organisms of the Hubbard Brook Valley, New Hampshire
Richard T. Holmes; Gene E. Likens
1999-01-01
Lists the organisms, both plant and animal, that have been identified by scientists engaged in multidisciplinary ecological research in the Hubbard Brook Valley, New Hampshire, during the past three decades. The Valley encompasses the Hubbard Brook Experimental Forest, Mirror Lake, and nearby areas within the White Mountain region of Grafton County. The species lists...
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21st Century jobs initiative - Tennessee`s Resource Valley. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-12-23
Tennessee`s Resource Valley, a regional economic development organization, was asked to facilitate a two-year, $750,000 grant from the Department of Energy. The grant`s purpose was to make the East Tennessee region less dependent on federal funds for its economic well-being and to increase regional awareness of the advantages of proximity to the Department of Energy facilities in Oak Ridge. The mission of Tennessee`s Resource Valley is to market the business location advantages of mid-East Tennessee to corporate decision makers and to facilitate regional initiatives that impact the creation of quality job opportunities. Tennessee`s Resource Valley represents fifteen (15) counties inmore » East Tennessee: Anderson, Blount, Campbell, Claiborne, Cocke, Grainger, Jefferson, Knox, Loudon, Monroe, Morgan, Roane, Scott, Sevier and Union.« less
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Hill, Mary C.; Ely, D. Matthew; Tiedeman, Claire; O'Brien, Grady M.; D'Agnese, Frank A.; Faunt, Claudia C.
2001-01-01
individual observation locations. This analysis is needed where observations are clustered to determine whether the area is important to the predictions of interest. (3) Finally, the method is used to evaluate omitting a set of 100 observation locations. The locations were selected because they had low individual ratings and were not one of the few locations at which hydraulic heads from deep in the system were measured. The major results of the three analyses, when applied to the three-layer DVRFS ground-water flow system, are described in the following paragraphs. The discussion is labeled using the numbers 1 to 3 to clearly relate it to the three ways the method is used, as listed above. (1) The individual observation location analysis indicates that three observation locations are most important. They are located in Emigrant Valley, Oasis Valley, and Beatty. Of importance is that these and other observations shown to be important by this analysis are far from the travel paths considered. This displays the importance of the regional setting within which the transport occurs, the importance of including some sites throughout the area in the monitoring network, and the importance of including sites in these areas in particular. The method considered in this report indicates that the 19 observation locations that reflect hydraulic heads deeper in the system (in model layers 1, 2, and 3) are not very important. This appears to be because the locations of these observations are in the vicinity of shallow observation locations that also generally are rated as low importance, and because the model layers are hydraulically well connected vertically. The value of deep observations to testing conceptual models, however, is stressed. As a result, the deep observations are rated higher than is consistent with the results of the analysis presented, and none of these observations are omitted in the scenario discussed under (3) below. (2) The geographic grouping of th
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Groundwater availability of the Central Valley Aquifer, California
Faunt, Claudia C.
2009-01-01
California's Central Valley covers about 20,000 square miles and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the Central Valley with an estimated value of $17 billion per year. This irrigated agriculture relies heavily on surface-water diversions and groundwater pumpage. Approximately one-sixth of the Nation's irrigated land is in the Central Valley, and about one-fifth of the Nation's groundwater demand is supplied from its aquifers. The Central Valley also is rapidly becoming an important area for California's expanding urban population. Since 1980, the population of the Central Valley has nearly doubled from 2 million to 3.8 million people. The Census Bureau projects that the Central Valley's population will increase to 6 million people by 2020. This surge in population has increased the competition for water resources within the Central Valley and statewide, which likely will be exacerbated by anticipated reductions in deliveries of Colorado River water to southern California. In response to this competition for water, a number of water-related issues have gained prominence: conservation of agricultural land, conjunctive use, artificial recharge, hydrologic implications of land-use change, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS Groundwater Resources Program made a detailed assessment of groundwater availability of the Central Valley aquifer system, that includes: (1) the present status of groundwater resources; (2) how these resources have changed over time; and (3) tools to assess system responses to stresses from future human uses and climate variability and change. This effort builds on previous investigations, such as the USGS Central Valley Regional Aquifer System and Analysis (CV-RASA) project and several other groundwater studies in the Valley completed by Federal, State and local agencies at differing scales. The
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The Central Valley Hydrologic Model
NASA Astrophysics Data System (ADS)
Faunt, C.; Belitz, K.; Hanson, R. T.
2009-12-01
Historically, California’s Central Valley has been one of the most productive agricultural regions in the world. The Central Valley also is rapidly becoming an important area for California’s expanding urban population. In response to this competition for water, a number of water-related issues have gained prominence: conjunctive use, artificial recharge, hydrologic implications of land-use change, subsidence, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS made a detailed assessment of the Central Valley aquifer system that includes the present status of water resources and how these resources have changed over time. The principal product of this assessment is a tool, referred to as the Central Valley Hydrologic Model (CVHM), that simulates surface-water flows, groundwater flows, and land subsidence in response to stresses from human uses and from climate variability throughout the entire Central Valley. The CVHM utilizes MODFLOW combined with a new tool called “Farm Process” to simulate groundwater and surface-water flow, irrigated agriculture, land subsidence, and other key processes in the Central Valley on a monthly basis. This model was discretized horizontally into 20,000 1-mi2 cells and vertically into 10 layers ranging in thickness from 50 feet at the land surface to 750 feet at depth. A texture model constructed by using data from more than 8,500 drillers’ logs was used to estimate hydraulic properties. Unmetered pumpage and surface-water deliveries for 21 water-balance regions were simulated with the Farm Process. Model results indicate that human activities, predominately surface-water deliveries and groundwater pumping for irrigated agriculture, have dramatically influenced the hydrology of the Central Valley. These human activities have increased flow though the aquifer system by about a factor of six compared to pre-development conditions. The simulated hydrology reflects spatial
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2017-05-09
Most of the oldest terrains on Mars have eroded into branching valleys, as seen here in by NASA's Mars Reconnaisance Orbiter, much like many land regions of Earth are eroded by rain and snowmelt runoff. This is the primary evidence for major climate change on Mars billions of years ago. How the climate of Mars could have supported a warmer and wetter environment has been the subject of scientific debates for 40 years. A full-resolution enhanced color closeup reveals details in the bedrock and dunes on the valley floor (upper left). The bedrock of ancient Mars has been hardened and cemented by groundwater. https://photojournal.jpl.nasa.gov/catalog/PIA21630
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NASA Astrophysics Data System (ADS)
Scanlon, B. R.; Zhang, Z.; Save, H.; Faunt, C. C.; Dettinger, M. D.
2015-12-01
Increasing concerns about drought impacts on water resources in California underscores the need to better understand effects of drought on water storage and coping strategies. Here we use a new GRACE mascons solution with high spatial resolution (1 degree) developed at the Univ. of Texas Center for Space Research (CSR) and output from the most recent regional groundwater model developed by the U.S. Geological Survey to evaluate changes in water storage in response to recent droughts. We also extend the analysis of drought impacts on water storage back to the 1980s using modeling and monitoring data. The drought has been intensifying since 2012 with almost 50% of the state and 100% of the Central Valley under exceptional drought in 2015. Total water storage from GRACE data declined sharply during the current drought, similar to the rate of depletion during the previous drought in 2007 - 2009. However, only 45% average recovery between the two droughts results in a much greater cumulative impact of both droughts. The CSR GRACE Mascons data offer unprecedented spatial resolution with no leakage to the oceans and no requirement for signal restoration. Snow and reservoir storage declines contribute to the total water storage depletion estimated by GRACE with the residuals attributed to groundwater storage. Rates of groundwater storage depletion are consistent with the results of regional groundwater modeling in the Central Valley. Traditional approaches to coping with these climate extremes has focused on surface water reservoir storage; however, increasing conjunctive use of surface water and groundwater and storing excess water from wet periods in depleted aquifers is increasing in the Central Valley.
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Geoenvironmental studies on conservation of archaeological sites at Siwa oasis, Egypt
NASA Astrophysics Data System (ADS)
Ibrahim, Hani A. M.; Kamh, Gamal E.
2006-02-01
Siwa oasis is located in the extreme western part of the Egyptian western desert. There are several archaeological sites in the oasis; the most distinct ones are Alexander the Great temple at Aghormi hill and the Gebel El Mota tomb excavations. They have suffered due to deterioration and cracks of different kinds and some parts are getting worse as rock falls occur. From field inspection and lab analysis, it is clear that lithology plays an important role on the extent of damage. Alexander the Great temple was built over the northern edge of Aghormi hill, which consists of two distinct beds—an upper limestone bed and a lower shale one. From field survey and laboratory analysis, the shale is considered as a high expanded bed and weak in its bearing capacity, as its clay content (mainly smectite) experienced swelling due to wetting from the ground water spring underneath. Consequently, the upper limestone bed suffered from map cracking associated with rock falls due to the differential settlement of the swelled lower shale one. The temple was threatened by slope instability and had experienced many cracks. At Gabal El Mota tomb excavations, it was noticed that a comparison of tombs of the same opening size revealed that those that excavated on shale beds had cracked much more than those that excavated on limestone. This may be attributed to the low bearing capacity of excavated shale walls. The remedial measures suggested to overcome the stability problems on these archaeological sites are grouting or construction of retaining walls.
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Li, Hai-Feng; Zeng, Fan-Jiang; Gui, Dong-Wei; An, Gui-Xiang; Liu, Zhen; Zhang, Li-Gang; Liu, Bo
2012-01-01
Taking Cele oasis at the southern fringe of Taklimakan Desert as a case, this paper studied the effects of different disturbances (burning in spring, cutting in spring, and cutting in fall) on the morphological characteristics and aboveground biomass of natural vegetation Alhagi sparsifolia in the ecotone of oasis-desert. Burning in spring decreased the A. sparsifolia plant height, crown width, and biomass significantly, being harmful to the regeneration and growth of the vegetation. Cutting in spring decreased the A. sparsifolia plant height, crown width, and biomass but increased the leaf biomass, thorn length, and thorn diameter, whereas cutting in fall decreased the plant height and crown width but increased the ramification amount and biomass of A. sparsifolia. Moderate cutting in fall could benefit the protection of A. sparsifolia at the southern fringe of Taklimakan Desert.
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NASA Astrophysics Data System (ADS)
Jiang, Y.; Huang, G., Sr.; Xu, X.; Huang, Q.; Huo, Z.
2015-12-01
Severe water scarcity and unreasonable allocation are threatening the eco-environment in the Heihe River basin (HRB), an arid and semi-arid watershed in Northwest China. The water use in the middle oasis accounts for about 70% of the total water use in the HRB, in which over 85% are consumed by irrigated agriculture. Thus the regional assessment and improvement of irrigation water use are quite essential for water-saving and eco-environmental sustainability. This paper applied a distributed agro-hydrological model (SWAP-EPIC) integrated with ArcGIS to investigate the irrigation water use efficiency (WUE) in the middle oasis. The detailed distributed data in 2012, including soil properties, irrigation schedules, crop pattern and calendar, were collected and used in the regional simulation. The spatial-temporal distribution of LAI and evapotranspiration (ETa) from remote sensing were used as observations to calibrate the model. Results showed that the simulation data was in a good agreement with the observation one. The relative WUE (i.e. divided by the mean value) ranged from 0.77 to 1.33 in different canal command areas. Large spatial variations of WUE were mainly caused by the non-uniform distribution of irrigation water. The present irrigation performance was poor, and only 50% of total irrigation amount was finally utilized through evapotranspiration in the whole district. While nearly 24% of the irrigation water were lost through field deep percolation and 26% were wasted in canal conveyance. Further analysis of water-saving scenarios was conducted through applying the improved irrigation schedule for each crop-soil unites and increasing the canal conveyance efficiency. Prediction showed that 15% of total irrigation amount can be saved without reduction of crop yield.
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Monitoring of Microseismicity with ArrayTechniques in the Peach Tree Valley Region
NASA Astrophysics Data System (ADS)
Garcia-Reyes, J. L.; Clayton, R. W.
2016-12-01
This study is focused on the analysis of microseismicity along the San Andreas Fault in the PeachTree Valley region. This zone is part of the transition zone between the locked portion to the south (Parkfield, CA) and the creeping section to the north (Jovilet, et al., JGR, 2014). The data for the study comes from a 2-week deployment of 116 Zland nodes in a cross-shaped configuration along (8.2 km) and across (9 km) the Fault. We analyze the distribution of microseismicity using a 3D backprojection technique, and we explore the use of Hidden Markov Models to identify different patterns of microseismicity (Hammer et al., GJI, 2013). The goal of the study is to relate the style of seismicity to the mechanical state of the Fault. The results show the evolution of seismic activity as well as at least two different patterns of seismic signals.
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Gravity Data from Newark Valley, White Pine County, Nevada
Mankinen, Edward A.; McKee, Edwin H.
2007-01-01
The Newark Valley area, eastern Nevada is one of thirteen major ground-water basins investigated by the BARCAS (Basin and Range Carbonate Aquifer Study) Project. Gravity data are being used to help characterize the geophysical framework of the region. Although gravity coverage was extensive over parts of the BARCAS study area, data were sparse for a number of the valleys, including the northern part of Newark Valley. We addressed this lack of data by establishing seventy new gravity stations in and around Newark Valley. All available gravity data were then evaluated to determine their reliability, prior to calculating an isostatic residual gravity map to be used for subsequent analyses. A gravity inversion method was used to calculate depths to pre-Cenozoic basement rock and estimates of maximum alluvial/volcanic fill. The enhanced gravity coverage and the incorporation of lithologic information from several deep oil and gas wells yields a view of subsurface shape of the basin and will provide information useful for the development of hydrogeologic models for the region.
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Li, Xin; Liu, Shaomin; Xiao, Qin; Ma, Mingguo; Jin, Rui; Che, Tao; Wang, Weizhen; Hu, Xiaoli; Xu, Ziwei; Wen, Jianguang; Wang, Liangxu
2017-01-01
We introduce a multiscale dataset obtained from Heihe Watershed Allied Telemetry Experimental Research (HiWATER) in an oasis-desert area in 2012. Upscaling of eco-hydrological processes on a heterogeneous surface is a grand challenge. Progress in this field is hindered by the poor availability of multiscale observations. HiWATER is an experiment designed to address this challenge through instrumentation on hierarchically nested scales to obtain multiscale and multidisciplinary data. The HiWATER observation system consists of a flux observation matrix of eddy covariance towers, large aperture scintillometers, and automatic meteorological stations; an eco-hydrological sensor network of soil moisture and leaf area index; hyper-resolution airborne remote sensing using LiDAR, imaging spectrometer, multi-angle thermal imager, and L-band microwave radiometer; and synchronical ground measurements of vegetation dynamics, and photosynthesis processes. All observational data were carefully quality controlled throughout sensor calibration, data collection, data processing, and datasets generation. The data are freely available at figshare and the Cold and Arid Regions Science Data Centre. The data should be useful for elucidating multiscale eco-hydrological processes and developing upscaling methods. PMID:28654086
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Origin of the Valley Networks On Mars: A Hydrological Perspective
NASA Technical Reports Server (NTRS)
Gulick, Virginia C.
2000-01-01
The geomorphology of the Martian valley networks is examined from a hydrological perspective for their compatibility with an origin by rainfall, globally higher heat flow, and localized hydrothermal systems. Comparison of morphology and spatial distribution of valleys on geologic surfaces with terrestrial fluvial valleys suggests that most Martian valleys are probably not indicative of a rainfall origin, nor are they indicative of formation by an early global uniformly higher heat flow. In general, valleys are not uniformly distributed within geologic surface units as are terrestrial fluvial valleys. Valleys tend to form either as isolated systems or in clusters on a geologic surface unit leaving large expanses of the unit virtually untouched by erosion. With the exception of fluvial valleys on some volcanoes, most Martian valleys exhibit a sapping morphology and do not appear to have formed along with those that exhibit a runoff morphology. In contrast, terrestrial sapping valleys form from and along with runoff valleys. The isolated or clustered distribution of valleys suggests localized water sources were important in drainage development. Persistent ground-water outflow driven by localized, but vigorous hydrothermal circulation associated with magmatism, volcanism, impacts, or tectonism is, however, consistent with valley morphology and distribution. Snowfall from sublimating ice-covered lakes or seas may have provided an atmospheric water source for the formation of some valleys in regions where the surface is easily eroded and where localized geothermal/hydrothermal activity is sufficient to melt accumulated snowpacks.
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Stamos, Christina L.; Christensen, Allen H.; Langenheim, Victoria
2017-07-19
The increasing demands on groundwater for water supply in desert areas in California and the western United States have resulted in the need to better understand groundwater sources, availability, and sustainability. This is true for a 650-square-mile area that encompasses the Antelope Valley, El Mirage Valley, and Upper Mojave River Valley groundwater basins, about 50 miles northeast of Los Angeles, California, in the western part of the Mojave Desert. These basins have been adjudicated to ensure that groundwater rights are allocated according to legal judgments. In an effort to assess if the boundary between the Antelope Valley and El Mirage Valley groundwater basins could be better defined, the U.S. Geological Survey began a cooperative study in 2014 with the Mojave Water Agency to better understand the hydrogeology in the area and investigate potential controls on groundwater flow and availability, including basement topography.Recharge is sporadic and primarily from small ephemeral washes and streams that originate in the San Gabriel Mountains to the south; estimates range from about 400 to 1,940 acre-feet per year. Lateral underflow from adjacent basins has been considered minor in previous studies; underflow from the Antelope Valley to the El Mirage Valley groundwater basin has been estimated to be between 100 and 1,900 acre-feet per year. Groundwater discharge is primarily from pumping, mostly by municipal supply wells. Between October 2013 and September 2014, the municipal pumpage in the Antelope Valley and El Mirage Valley groundwater basins was reported to be about 800 and 2,080 acre-feet, respectively.This study was motivated by the results from a previously completed regional gravity study, which suggested a northeast-trending subsurface basement ridge and saddle approximately 3.5 miles west of the boundary between the Antelope Valley and El Mirage Valley groundwater basins that might influence groundwater flow. To better define potential basement
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NASA Astrophysics Data System (ADS)
Heyerdahl, Håkon; Høydal, Øyvind
2016-04-01
The Gudbrandsdalen valley in Eastern Norway lies in a region where annual precipitation is generally low (down to 300 mm/year). The landslide activity has consequently historically been low, although the lower part of the valley sides generally is draped with thick layers of Quaternary deposits, primarily of glacial or glaciofluvial origin. The perception of natural hazards in the valley was previously primarily connected to flooding in the main river in the valley bottom during early summer, due to large discharges resulting from snowmelt in the mountainous regions west and east of the valley. However, several high-intensity events have changed the image of the region. Starting with a localized, but intense, landslide event in the Northern part of the valley in year 2008, two larger events covering almost the entire valley occurred in the years 2011 and 2013. A high number of landslides was triggered in all these events, including many flash floods and debris flows/debris slides in small and steep tributary rivers along the valley slopes. Landslide triggering covers different release mechanisms: In 2008, landslides were triggered without precipitation in not-frozen soil deposits without snow cover in the lower part of the valley. Groundwater flow through the permeable bedrock ("Otta schist") resulting from snow-melt in the elevated mountainous areas caused landslide triggering due to positive pore-water pressures forming at the bedrock surface below soil deposits, or at depressions in the terrain. Subsequent rainfall resulted in even more landslides being released. In later events (years 2011 and 2013) many landslides were caused by surface water taking new paths downslope, often due to man-made changes in existing waterways (typically poorly planned drainage solutions or new roads). Relatively small discharges in slopes with unconsolidated and easily erodible glacial deposits (typically lateral moraine) in many cases lead to small initial slides that down
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OASYS (OrAnge SYnchrotron Suite): an open-source graphical environment for x-ray virtual experiments
NASA Astrophysics Data System (ADS)
Rebuffi, Luca; Sanchez del Rio, Manuel
2017-08-01
The evolution of the hardware platforms, the modernization of the software tools, the access to the codes of a large number of young people and the popularization of the open source software for scientific applications drove us to design OASYS (ORange SYnchrotron Suite), a completely new graphical environment for modelling X-ray experiments. The implemented software architecture allows to obtain not only an intuitive and very-easy-to-use graphical interface, but also provides high flexibility and rapidity for interactive simulations, making configuration changes to quickly compare multiple beamline configurations. Its purpose is to integrate in a synergetic way the most powerful calculation engines available. OASYS integrates different simulation strategies via the implementation of adequate simulation tools for X-ray Optics (e.g. ray tracing and wave optics packages). It provides a language to make them to communicate by sending and receiving encapsulated data. Python has been chosen as main programming language, because of its universality and popularity in scientific computing. The software Orange, developed at the University of Ljubljana (SLO), is the high level workflow engine that provides the interaction with the user and communication mechanisms.
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El-Naggar, Hesham M
2010-01-01
Ground water is the only water resource for Siwa Oasis. It is obtained from natural freshwater wells and springs fed by the Nubian aquifer. Water samples collected from Siwa Oasis had relatively higher iron (Fe) and manganese (Mn) than the permissible limits specified in WHO Guidelines and Egyptian Standards for drinking water quality. Aeration followed by sand filtration is the most commonly used method for the removal of iron from ground water. The study aimed at development of low-cost technology for the removal of iron and manganese from ground water in Siwa Oasis. The study was carried out on Laboratory-scale columns experiments sand filters with variable depths of 15, 30, 45, 60, 75, 90 cm and three graded types of sand were studied. The graded sand (E.S. =0.205 mm, U.C. =3.366, depth of sand = 60 cm and filtration rate = 1.44 m3/m2/hr) was the best type of filter media. Iron and manganese concentrations measured in ground water with aeration only, decreased with an average removal percentage of 16%, 13% respectively. Iron and manganese concentrations after filtration with aeration came down to 0.1123, 0.05 mg/L respectively in all cases from an initial concentration of 1.14, 0.34 mg/L respectively. Advantages of such treatment unit included simplicity, low cost design, and no need for chemical addition. In addition, the only maintenance required was periodic washing of the sand filter or replacement of the sand in order to maintain reasonable flow rate through the system.
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Water availability and subsidence in California's Central Valley
Faunt, Claudia C.; Sneed, Michelle
2015-01-01
California’s Central Valley covers about 52,000 square kilometers (km2) and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the broad alluvial filled structural trough, with an estimated value exceeding $20 billion per year (Faunt 2009) (Figure 1). Central Valley agriculture depends on state and federal water systems that divert surface water, predominantly originating from Sierra Nevada snowmelt, to agricultural fields. Because the valley is semi-arid and the availability of surface water varies substantially from year to year, season to season, and from north to south, agriculture, as it grew, developed a reliance on groundwater for irrigation.
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NASA Astrophysics Data System (ADS)
Kreemer, C. W.; Hammond, W. C.; Blewitt, G.
2009-12-01
The Sierra Nevada - Great Valley (SNGV) micro-plate has long been recognized as a tectonically rigid, though mobile, entity within the Pacific - North America plate boundary zone. The motion of the SNGV relative to stable North America (and the Colorado Plateau) provides the kinematic boundary condition for, and perhaps drives, the deformation in the Basin and Range Province (BRP) and Walker Lane. In the north the motion of the SNGV is aligned with the Mohawk Valley fault zone, which could have a slip rate of over a few mm/yr. The crest of the Sierras marks the SNGV’s eastern edge, but the obliquity between orientation of this boundary and the block’s motion implies an expected increase in rangefront-normal extension from the northern to southern Walker Lane. We use new GPS data from the EarthScope Plate Boundary Observatory (PBO) and our own semi-continuous MAGNET network to revisit the following questions: 1) Do the data still support rigidity of the SNGV?; 2) How far east does the rigidity extend and how does this relate to SNGV lithology?; 3) How does the direction of SNGV motion relate to the strike of its eastern margin and observed strain partitioning (and its along strike variation) in the Walker Lane?; and 4) How is SNGV-BRP motion accommodated between the Walker Lane and the Cascadia forearc? We analyze data from all the available continuous GPS sites in the greater SNGV region, including new data from PBO, as well as data from MAGNET. All data are processed with the GIPSY-OASIS II precise point positioning software using recently reprocessed orbits from JPL's IGS Analysis Center. The processing includes satellite and station antenna calibrations and all data have the phase ambiguities fixed using the Ambizap algorithm. Positions are estimated in our custom-made North America reference frame in which continental-scale common-mode errors are removed. Velocities and uncertainties are estimated using the CATS software in which we assuming an error model
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Belcher, Wayne R.
2004-01-01
A numerical three-dimensional (3D) transient ground-water flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the ground-water flow system and previous less extensive ground-water flow models were incorporated and reevaluated together with new data to provide greater detail for the complex, digital model. A 3D digital hydrogeologic framework model (HFM) was developed from digital elevation models, geologic maps, borehole information, geologic and hydrogeologic cross sections, and other 3D models to represent the geometry of the hydrogeologic units (HGUs). Structural features, such as faults and fractures, that affect ground-water flow also were added. The HFM represents Precambrian and Paleozoic crystalline and sedimentary rocks, Mesozoic sedimentary rocks, Mesozoic to Cenozoic intrusive rocks, Cenozoic volcanic tuffs and lavas, and late Cenozoic sedimentary deposits of the Death Valley Regional Ground-Water Flow System (DVRFS) region in 27 HGUs. Information from a series of investigations was compiled to conceptualize and quantify hydrologic components of the ground-water flow system within the DVRFS model domain and to provide hydraulic-property and head-observation data used in the calibration of the transient-flow model. These studies reevaluated natural ground-water discharge occurring through evapotranspiration and spring flow; the history of ground-water pumping from 1913 through 1998; ground-water recharge simulated as net infiltration; model boundary inflows and outflows based on regional hydraulic gradients and water budgets of surrounding areas; hydraulic conductivity and its relation to depth; and water levels appropriate for regional simulation of prepumped and pumped conditions within the DVRFS model domain. Simulation results appropriate for the regional extent and scale of the model were
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Radon Outgassing in the Casa Diablo Region, Long Valley Caldera, California
NASA Astrophysics Data System (ADS)
Adarkwah, N.; Cuff, K.
2003-12-01
A radon outgassing survey has been conducted in the Casa Diablo region of the Long Valley Caldera. The Long Valley Caldera (LVC) is an active volcanic system situated along the eastern front of the Sierra Nevada mountain range in east-central California. The survey was centered in an area .4 km northwest of the Casa Diablo geothermal power plant, located along the southwestern-most rim of the caldera?s resurgent dome. Results from previous radon emission studies in LVC indicate that high degrees of outgassing occur in association with relatively narrow networks of unsealed fractures (Cuff, et al., 2000 and Hoyos, et al., 2001). These fracture networks act as pathways for radon and other gases generated at depth as they migrate toward the surface. The purpose of the present study was to determine whether or not a relationship exists between radon emissions in the current survey area and that in a previously surveyed area approximately .8 km west of the geothermal plant. To accomplish this, we measured radon concentration in soil-gas at 35 separate sites. These sites were located within a 140 by 100 meter grid, with 20 meter spacing between each sample site. A radon outgassing map was then created using measured concentration values along with longitude and latitude values for each sample location. Geologic maps of the area were also analyzed and compared with radon outgassing maps. Analysis of these maps indicates that radon outgassing occurs through a set of crisscrossing fractures, trending southwest-northeast and northwest-southeast respectively. The northwest trending fractures are related to mapped normal faults in the area, while those with a southwest-northeast orientation are associated with an unmapped zone of faulting that is roughly perpendicular to the other faults. The latter set of fractures has a trend similar to that discovered in the previously surveyed area to the west. In both areas the highest readings were in excess of three times background
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Battaglia, Maurizio; Dzurisin, Daniel; Langbein, John; Svarc, Jerry; Hill, David P.
2008-01-01
A GPS survey of leveling benchmarks done in Long Valley Caldera in 1999 showed that the application of the National Geodetic Survey (NGS) geoid model GEOID99 to tie GPS heights to historical leveling measurements would significantly underestimate the caldera ground deformation (known from other geodetic measurements). The NGS geoid model was able to correctly reproduce the shape of the deformation, but required a local adjustment to give a realistic estimate of the magnitude of the uplift. In summer 2006, the U.S. Geological Survey conducted a new leveling survey along two major routes crossing the Long Valley region from north to south (Hwy 395) and from east to west (Hwy 203 - Benton Crossing). At the same time, 25 leveling bench marks were occupied with dual frequency GPS receivers to provide a measurement of the ellipsoid heights. Using the heights from these two surveys, we were able to compute a precise geoid height model (LVGEOID) for the Long Valley volcanic region. Our results show that although the LVGEOID and the latest NGS GEOID03 model practically coincide in areas outside the caldera, there is a difference of up to 0.2 m between the two models within the caldera. Accounting for this difference is critical when using the geoid height model to estimate the ground deformation due to magmatic or tectonic activity in the caldera.
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Utilizing Lidar Data for Detection of Channel Migration: Taylor Valley, Antarctica
NASA Astrophysics Data System (ADS)
Barlow, M. C.; Telling, J. W.; Glennie, C.; Fountain, A.
2017-12-01
The McMurdo Dry Valleys is the largest ice-free expanse in Antarctica and one of the most studied regions on the continent. The valleys are a hyper-arid, cold-polar desert that receives little precipitation (<50 mm weq yr-1). The valley bottoms are covered in a sandy-gravel, dotted with ice-covered lakes and ponds, and alpine glaciers that descend from the surrounding mountains. Glacial melt feeds the lakes via ephemeral streams that flow 6 - 10 weeks each summer. Field observations indicate that the valley floors, particularly in Taylor Valley, contain numerous abandoned stream channels but, given the modest stream flows, channel migration is rarely observed. Only a few channels have been surveyed in the field due to the slow pace of manual methods. Here we present a method to assess channel migration over a broad region in order to study the pattern of channel migration as a function of climatic and/or geologic gradients in Taylor Valley. Raster images of high-resolution topography were created from two lidar (Light Detection and Ranging) datasets and were used to analyze channel migration in Taylor Valley. The first lidar dataset was collected in 2001 by NASA's Airborne Topographic Mapper (ATM) and the second was collected by the National Center for Airborne Laser Mapping (NCALM) in 2014 with an Optech Titan Sensor. The channels were extracted for each dataset using GeoNet, which is an open source tool used for the automatic extraction of channel networks. Channel migration was found to range from 0 to 50 cm per year depending upon the location. Channel complexity was determined based on the change in the number of channel branches and their length. We present the results for various regions in Taylor Valley with differing degrees of stream complexity. Further research is being done to determine factors that drive channel migration rates in this unique environment.
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NASA Astrophysics Data System (ADS)
1984-12-01
Surface landforms in the Salt Valley Area are generally a function of the Salt Valley anticline and are characterized by parallel and subparallel cuestaform ridges and hogbacks and flat valley floors. The most prominent structure in the Area is the Salt Valley anticline. Erosion resulting from the Tertiary uplift of the Colorado Plateau led to salt dissolution and subsequent collapse along the crest of the anticline. Continued erosion removed the collapse material, forming an axial valley along the crest of the anticline. Paleozoic rocks beneath the salt bearing Paradox Formation consist of limestone, dolomite, sandstone, siltstone and shale. The salt beds of the Paradox formation occur in distinct cycles separated by an interbed sequence of anhydrite, carbonate, and clastic rocks. The Paradox Formation is overlain by Pennsylvanian limestone; Permian sandstone; and Mesozoic sandstone, mudstone, conglomerate and shale. No earthquakes have been reported in the area during the period of the historic record and contemporary seismicity appears to be diffusely distributed, of low level and small magnitude. The upper unit includes the Permian strata and upper Honaker trail formation.
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Diversity and cold adaptation of microorganisms isolated from the Schirmacher Oasis, Antarctica
NASA Astrophysics Data System (ADS)
Mojib, Nazia; Bej, Asim K.; Hoover, Richard
2008-08-01
We have investigated the feasibility of the PCR amplification of the 16S rRNA genes from eubacteria and Archea on samples collected on Whatman FTA filters from Schirmacher Oasis for the study of culture-independent analysis of the microbial diversity. Both conventional PCR and real-time TaqmaTM PCR successfully amplified the targeted genes. A number of diverse groups of psychrotolerant microorganisms with various pigments have been isolated when cultured on agar medium. 16S rRNA gene analysis of these isolates helped us to identify closest taxonomic genus Pseudomonas, Frigoribacterium, Arthrobacter, Flavobacterium, and Janthinobacterium. It is possible that the pigments play protective role from solar UV radiation, which is prevalent in Antarctic continent especially during Austral summer months. Study of the expression of cold adaptive protein CapB and ice-binding protein IBP using western blots showed positive detection of both or either of these proteins in 6 out of 8 isolates. Since the CapB and IBP protein structure greatly varies in microorganisms, it is possible that the 2 isolates with negative results could have a different class of these proteins. The expression of the CapB and the IBP in these isolates suggest that these proteins are essential for the survival in the Antarctic cold and subzero temperatures and protect themselves from freeze-damage. The current study provided sufficient data to further investigate the rich and diverse biota of psychrotolerant extremophiles in the Antarctic Schirmacher Oasis using both culture-independent and culture-based approaches; and understand the mechanisms of cold tolerance.
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Pavelko, Michael T.
2010-01-01
The water-level database for the Death Valley regional groundwater flow system in Nevada and California was updated. The database includes more than 54,000 water levels collected from 1907 to 2007, from more than 1,800 wells. Water levels were assigned a primary flag and multiple secondary flags that describe hydrologic conditions and trends at the time of the measurement and identify pertinent information about the well or water-level measurement. The flags provide a subjective measure of the relative accuracy of the measurements and are used to identify which water levels are appropriate for calculating head observations in a regional transient groundwater flow model. Included in the report appendix are all water-level data and their flags, selected well data, and an interactive spreadsheet for viewing hydrographs and well locations.
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Valley-dependent band structure and valley polarization in periodically modulated graphene
NASA Astrophysics Data System (ADS)
Lu, Wei-Tao
2016-08-01
The valley-dependent energy band and transport property of graphene under a periodic magnetic-strained field are studied, where the time-reversal symmetry is broken and the valley degeneracy is lifted. The considered superlattice is composed of two different barriers, providing more degrees of freedom for engineering the electronic structure. The electrons near the K and K' valleys are dominated by different effective superlattices. It is found that the energy bands for both valleys are symmetric with respect to ky=-(AM+ξ AS) /4 under the symmetric superlattices. More finite-energy Dirac points, more prominent collimation behavior, and new crossing points are found for K' valley. The degenerate miniband near the K valley splits into two subminibands and produces a new band gap under the asymmetric superlattices. The velocity for the K' valley is greatly renormalized compared with the K valley, and so we can achieve a finite velocity for the K valley while the velocity for the K' valley is zero. Especially, the miniband and band gap could be manipulated independently, leading to an increase of the conductance. The characteristics of the band structure are reflected in the transmission spectra. The Dirac points and the crossing points appear as pronounced peaks in transmission. A remarkable valley polarization is obtained which is robust to the disorder and can be controlled by the strain, the period, and the voltage.
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Maja Valley and the Chryse outflow complex sites
NASA Technical Reports Server (NTRS)
Rice, Jim W.
1994-01-01
This candidate landing site is located at 19 deg N, 53.5 deg W near the mouth of a major outflow channel. Maja Valles, and two 'valley network' channel systems, Maumee and Vedra Valles. The following objectives are to be analyzed in this region: (1) origin and paleohydrology of outflow and valley network channels; (2) fan delta complex composition (the deposit located in this area is one of the few identified at the mouth s of any channels on the planet); and (3) analysis of any paleolake sediments (carbonates, evaporites). The primary objectives of the Chryse Outflow Complex region (Ares, Tiu, Mawrth, Simud, and Shalbatana Valles) would be outflow channel dynamics (paleohydrology) of five different channel systems.
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The geochemistry of groundwater resources in the Jordan Valley: The impact of the Rift Valley brines
Farber, E.; Vengosh, A.; Gavrieli, I.; Marie, Amarisa; Bullen, T.D.; Mayer, B.; Polak, A.; Shavit, U.
2007-01-01
The chemical composition of groundwater in the Jordan Valley, along the section between the Sea of Galilee and the Dead Sea, is investigated in order to evaluate the origin of the groundwater resources and, in particular, to elucidate the role of deep brines on the chemical composition of the regional groundwater resources in the Jordan Valley. Samples were collected from shallow groundwater in research boreholes on two sites in the northern and southern parts of the Jordan Valley, adjacent to the Jordan River. Data is also compiled from previous published studies. Geochemical data (e.g., Br/Cl, Na/Cl and SO4/Cl ratios) and B, O, Sr and S isotopic compositions are used to define groundwater groups, to map their distribution in the Jordan valley, and to evaluate their origin. The combined geochemical tools enabled the delineation of three major sources of solutes that differentially affect the quality of groundwater in the Jordan Valley: (1) flow and mixing with hypersaline brines with high Br/Cl (>2 ?? 10-3) and low Na/Cl (<0.8) ratios; (2) dissolution of highly soluble salts (e.g., halite, gypsum) in the host sediments resulting in typically lower Br/Cl signal (<2 ?? 10-3); and (3) recharge of anthropogenic effluents, primarily derived from evaporated agricultural return flow that has interacted (e.g., base-exchange reactions) with the overlying soil. It is shown that shallow saline groundwaters influenced by brine mixing exhibit a north-south variation in their Br/Cl and Na/Cl ratios. This chemical trend was observed also in hypersaline brines in the Jordan valley, which suggests a local mixing process between the water bodies. ?? 2007 Elsevier Ltd. All rights reserved.
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Surface Deformation in Quetta Valley, Balochistan, Pakistan
NASA Astrophysics Data System (ADS)
Huang, J.; Shuhab, K.; Wulamu, A.; Crupa, W.; Khan, A. S.; Kakar, D. M.; Kasi, A.
2015-12-01
In February 2011, several ground fissures up to ~1.8 km in length appeared in the Quetta Valley, Balochsitan, Pakistan. It is not clear what caused the sudden occurrence of these fissures. The region is tectonically active and bounded to the west by several regional strike-slip faults including the north-south striking left-lateral Chaman fault system that slips at ~10 mm per year. Several large earthquakes have occurred recently in this area, one fatal 6.4 magnitude (Mw) earthquake occurred on October 28th, 2008. Some parts of Quetta Valley are subsiding; GPS data from two stations in Quetta that span mid-2006 - 2009 recorded subsidence rates of ~10 cm per year. Although subsidence in urban areas is generally attributed to groundwater depletion, it is not clear whether ground fissures are caused by water withdrawal or related to tectonics of the region. This study is designed to quantify and assess the source of surface deformation in Quetta Valley using InSAR, GPS, seismic and earthquake centroid moment tensor data. To detect and map the spatial-temporal features of the processes that led to the surface deformation, we used two time series, i.e., 15 European Remote Sensing (ERS-1/2) satellite images from 1992 - 1999 and 27 ENVISAT images spanning 2003 - 2010. A Differential Interferometric Synthetic Aperture Radar (DInSAR) Small Baseline Subset (SBAS) technique was used to investigate surface deformation. Eleven continuous-GPS stations within the InSAR antenna footprint were compared with the InSAR time series for quality control. Preliminary InSAR results revealed that the areas in and around the fissures are subsiding at 5 cm per year. Five seismic lines totaling ~60 km, acquired in 2003, were used to interpret faults beneath Holocene alluvium in the Quetta Valley. One of the blind faults is a north-south striking thrust fault mapped north into the Takatu range. However, a focal mechanism for the 2008 earthquake in this region indicated northwest
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NASA Astrophysics Data System (ADS)
Lima, R. D.; Hayman, N. W.; Prior, M. G.; Stockli, D. F.; Kelly, E. D.
2016-12-01
Deformation and temperature evolution during orogenic stages may influence later fabric development, thus controlling large-scale extensional processes that can occur millions of years later. Here, we describe pressure-temperature and fabric evolution from the Death Valley (DV) region and show how inherited fabrics, formed in late orogenic stages during Late Cretaceous time, influenced later Neogene age Basin and Range (BR) extension. The DV region is one of the most extended and thinned regions in the western US BR province, and the two of the ranges that bound the eastern valley expose basement rocks exhumed during the Neogene extension. In the Funeral range, it has been established that older (Precambrian) basement underwent Mesozoic age syn-deformational metamorphism during the Sevier-Laramide orogeny. In contrast, the Black Mountains record widespread tectonic stretching and magmatism of Miocene age on Precambrian basement, and have, overall, been lacking previous evidence of Mesozoic metamorphism and fabric development. In the Funeral Range Late Cretaceous migmatitic fabrics were overprinted by zones of high-strain fabrics formed due to melt-consuming reaction that define an overall P-T cooling path likely during late- to post-orogenesis. These fabrics form interconnected layers of quartz + biotite aggregates, in which individual quartz grains lack evidence of intracrystalline plastic deformation and show consistently random [c]-axis microfabrics. This suggests coupled reaction-diffusion processes that favored diffusion-assisted creep. New geochronometric results of melt products in the Black Mountains show evidence of partial melting of Late Cretaceous age. Contrasting with the neighboring Funeral Range, overprinting by extensional fabrics of Miocene age is widespread, and consists of high-strain, anastomosing foliation composed of retrograde products from preexisting, higher-temperature fabrics. These include interconnected fine-grained chlorite + quartz
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ERIC Educational Resources Information Center
National Oceanic and Atmospheric Administration (DOC), Washington, DC. Environmental Data Service.
OASIS (Oceanic and Atmospheric Scientific Information System) is an information retrieval service that furnishes ready reference to the technical literature and research efforts concerning the environmental sciences and marine and coastal resources. It provides computerized searches of both NOAA (National Oceanic and Atmospheric Administration)…
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NASA Astrophysics Data System (ADS)
Morgan, Gareth A.; Head, James W.; Marchant, David R.
2009-07-01
In order to assess the nature, degradational processes and history of the dichotomy boundary on Mars, we conducted a detailed morphological analysis of a 70,000 km2 region of its northern portion (north-central Deuteronilus Mensae, south of Lyot, in the vicinity of Sinton Crater). This region is characterized by the distinctive sinuous ∼2 km-high plateau scarp boundary, outlying massifs to the north, and extensive fretted valleys dissecting the plateau to the south. These features represent the first-order modification and retreat of the dichotomy boundary, and are further modified by processes that form lineated valley fill (LVF) in the fretted valleys, and lobate debris aprons (LDA) along the dichotomy scarp and surrounding the outlying massifs. We use new high-resolution image and topography data to examine the nature and origin of LVF and LDA and to investigate the climatic and accompanying degradational history of the escarpment. On the basis of our analysis, we conclude that: (1) LVF and LDA deposits within the study region are comprised of the same material, show integrated flow patterns, and originate as debris-covered valley glaciers; a significant amount of ice (hundreds of meters) is likely to remain today beneath a thin cover of sublimation till. (2) There is depositional evidence to suggest glacial highstands at least 800 m above the present level, implying previous conditions in which the distribution of ice was much more widespread; this is supported by similar deposits within many other areas across the dichotomy boundary. (3) The timing of the most recent large-scale activity of the LDA/LVF in this area is about 100-500 million years ago, similar to ages reported elsewhere along the dichotomy boundary. (4) There is evidence for a secondary, but significantly limited phase of glaciation; the deposits of which are limited to the vicinity of the alcoves; similar later phases have also been reported elsewhere along the dichotomy boundary. (5
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Scheirer, Daniel S.; Andreasen, Arne Dossing
2008-01-01
In March 2008, we collected gravity data along 12 traverses across newly-mapped faults in the Moapa Valley region of Clark County, Nevada. In areas crossed by these faults, the traverses provide better definition of the gravity field and, thus, the density structure, than prior gravity observations. Access problems prohibited complete gravity coverage along all of the planned gravity traverses, and we added and adjusted the locations of traverses to maximize our data collection. Most of the traverses exhibit isostatic gravity anomalies that have gradients characteristic of exposed or buried faults, including several of the newly-mapped faults.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Crist
2008-12-31
As stated in the proposal: Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, evaluated the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury and associated fine particulate matter. This evaluation involved two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring included the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station contains sampling equipment tomore » collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NOx, SO2, O3, etc.). Laboratory analyses of time-integrated samples were used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Nearreal- time measurements were used to measure the ambient concentrations of PM mass and all gaseous species including Hg0 and RGM. Approximately 30 months of field data were collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data provides mercury, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis includes (1) development of updated inventories of mercury emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg0, RGM, and fine particulate matter in the different sectors of the study region to identify key
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ERIC Educational Resources Information Center
Woo, Chung Wan
2012-01-01
Using qualitative research methods, this dissertation closely examines discourses and representations of disability from the cinematic images of disabled characters and their families in two South Korean films, "Oasis" (C. Lee, 2002) and "Malaton" (Y. Jung, 2005) as well as from the responses of nineteen Korean graduate…
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Sweetkind, Donald S.; Fridrich, Christopher J.; Taylor, Emily
2001-01-01
Existing hydrologic models of the Death Valley region typically have defined the Cenozoic basins as those areas that are covered by recent surficial deposits, and have treated the basin-fill deposits that are concealed under alluvium as a single unit with uniform hydrologic properties throughout the region, and with depth. Although this latter generalization was known to be flawed, it evidently was made because available geologic syntheses did not provide the basis for a more detailed characterization. As an initial attempt to address this problem, this report presents a compilation and synthesis of existing and new surface and subsurface data on the lithologic variations between and within the Cenozoic basin fills of this region. The most permeable lithologies in the Cenozoic basin fills are freshwater limestones, unaltered densely welded tuffs, and little-consolidated coarse alluvium. The least permeable lithologies are playa claystones, altered nonwelded tuffs, and tuffaceous and clay-matrix sediments of several types. In all but the youngest of the basin fills, permeability probably decreases strongly with depth owing to a typically increasing abundance of volcanic ash or clay in the matrices of the clastic sediments with increasing age (and therefore with increasing depth in general), and to increasing consolidation and alteration (both hydrothermal and diagenetic) with increasing depth and age. This report concludes with a categorization of the Cenozoic basins of the Death Valley region according to the predominant lithologies in the different basin fills and presents qualitative constraints on the hydrologic properties of these major lithologic categories.
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NASA Astrophysics Data System (ADS)
Lawson, M. J.; Yin, A.; Rhodes, E. J.
2015-12-01
Steep landscapes are known to provide sediment to sink regions, but often petrological factors can dominate basin sedimentation. Within Eureka Valley, in northwestern Death Valley National Park, normal faulting has exposed a steep cliff face on the western margin of the Last Chance range with four kilometers of vertical relief from the valley floor and an angle of repose of nearly 38 degrees. The cliff face is composed of Cambrian limestone and dolomite, including the Bonanza King, Carrara and Wood Canyon formations. Interacting with local normal faulting, these units preferentially break off the cliff face in coherent blocks, which result in landslide deposits rather than as finer grained material found within the basin. The valley is well known for a large sand dune, which derives its sediment from distal sources to the north, instead of from the adjacent Last Chance Range cliff face. During the Holocene, sediment is sourced primary from the northerly Willow Wash and Cucomungo canyon, a relatively small drainage (less than 80 km2) within the Sylvan Mountains. Within this drainage, the Jurassic quartz monzonite of Beer Creek is heavily fractured due to motion of the Fish Valley Lake - Death Valley fault zone. Thus, the quartz monzonite is more easily eroded than the well-consolidated limestone and dolomite that forms the Last Change Range cliff face. As well, the resultant eroded material is smaller grained, and thus more easily transported than the limestone. Consequently, this work highlights an excellent example of the strong influence that source material can have on basin sedimentation.
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NASA Astrophysics Data System (ADS)
Gulick, V. C.
2002-12-01
Despite three decades of exploration, the valley networks on Mars still seem to raise more questions than they answer. Valley systems have formed in the southern highlands, along some regions of the dichotomy boundary and the south rim of Valles Marineris, around the rim of some impact craters, and on the flanks of some volcanoes. They are found on some of the oldest and youngest terrains as well as on intermediate aged surfaces. There is surprisingly little consensus as to the formation and the paleoclimatic implications of the valley networks. Did the valleys require a persistent solar-driven atmospheric hydrological cycle involving precipitation, surface runoff, infiltration and groundwater outflow as they typically do on Earth? Or are they the result of magmatic or impact-driven thermal cycling of ground water involving persistent outflow and subsequent runoff? Are they the result of some other process(es)? Ground-water sapping, surface-water runoff, debris flows, wind erosion, and formation mechanisms involving other fluids have been proposed. Until such basic questions as these are definitively answered, their significance for understanding paleoclimatic change on Mars remains cloudy. I will review what is known about valley networks using data from both past and current missions. I will discuss what we have learned about their morphology, environments in which they formed, their spatial and temporal associations, possible formation mechanisms, relation to outflow channel and gully formation, as well as the possible implications for past climate change on Mars. Finally I will discuss how future, meter to submeter scale imaging and other remote sensing observations may shed new light on the debate over the origin of these enigmatic features.
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Extinction dynamics of a discrete population in an oasis.
Berti, Stefano; Cencini, Massimo; Vergni, Davide; Vulpiani, Angelo
2015-07-01
Understanding the conditions ensuring the persistence of a population is an issue of primary importance in population biology. The first theoretical approach to the problem dates back to the 1950s with the Kierstead, Slobodkin, and Skellam (KiSS) model, namely a continuous reaction-diffusion equation for a population growing on a patch of finite size L surrounded by a deadly environment with infinite mortality, i.e., an oasis in a desert. The main outcome of the model is that only patches above a critical size allow for population persistence. Here we introduce an individual-based analog of the KiSS model to investigate the effects of discreteness and demographic stochasticity. In particular, we study the average time to extinction both above and below the critical patch size of the continuous model and investigate the quasistationary distribution of the number of individuals for patch sizes above the critical threshold.
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OASIS connections: results from an evaluation study.
Czaja, Sara J; Lee, Chin Chin; Branham, Janice; Remis, Peggy
2012-10-01
The objectives of this study were to evaluate a community-based basic computer and Internet training program designed for older adults, provide recommendations for program refinement, and gather preliminary information on program sustainability. The program was developed by the OASIS Institute, a nonprofit agency serving older adults and implemented in 4 cities by community trainers across the United States. One hundred and ninety-six adults aged 40-90 years were assigned to the training or a wait-list control group. Knowledge of computers and the Internet, attitudes toward computers, and computer/Internet use were assessed at baseline, posttraining, and 3 months posttraining. The program was successful in increasing the computer/Internet skills of the trainees. The data indicated a significant increase in computer and Internet knowledge and comfort with computers among those who received the training. Further, those who completed the course reported an increase in both computer and Internet use 3 months posttraining. The findings indicate that a community-based computer and Internet training program delivered by community instructors can be effective in terms of increasing computer and Internet skills and comfort with computer technology among older adults.
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NASA Astrophysics Data System (ADS)
Hamiel, Yariv; Masson, Frederic; Piatibratova, Oksana; Mizrahi, Yaakov
2018-01-01
Detailed analysis of crustal deformation along the southern Arava Valley section of the Dead Sea Fault is presented. Using dense GPS measurements we obtain the velocities of new near- and far-field campaign stations across the fault. We find that this section is locked with a locking depth of 19.9 ± 7.7 km and a slip rate of 5.0 ± 0.8 mm/yr. The geodetically determined locking depth is found to be highly consistent with the thickness of the seismogenic zone in this region. Analysis of instrumental seismic record suggests that only 1% of the total seismic moment accumulated since the last large event occurred about 800 years ago, was released by small to moderate earthquakes. Historical and paleo-seismic catalogs of this region together with instrumental seismic data and calculations of Coulomb stress changes induced by the 1995 Mw 7.2 Nuweiba earthquake suggest that the southern Arava Valley section of the Dead Sea Fault is in the late stage of the current interseismic period.
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NASA Astrophysics Data System (ADS)
Calderón, M.; Cereceda, P.; Larrain, H.; Osses, P.; Pérez, L.; Ibáñez, M.
2010-07-01
Alto Patache coastal fog oasis is a protected area located south of Iquique, Northern Chile, being presently in charge of the Atacama Desert Center (ADC) research group of the Pontificia Universidad Católica de Chile, since 1997. On 2007, the Chilean Government bestowed a piece of land stretch covering 1,114 hectares to ADC scientific group for scientific research, ecosystem protection and environmental education. This oasis has been recently studied from different points of view: climate, biogeography, fog collection, geomorphology, soil survey and land use planning, plant distribution, conservation and archaeology. During 2009, a study of the geographical basis to elaborate a general management plan was undertaken to collect information to fulfill our planned out objectives. Through this study, georreferenciated strategic information was compiled to evaluate future actions conducting to a sustainable development within the protected area. This information was translated into thematic maps showing the spatial distribution of variables like: climate, geology, geomorphology, soils, vegetation, fauna, archaeological sites and management zones. The methodology used is the analysis of satellite imagery, using GPS by creating a cartographic Data Base incorporated in GIS. Results show that the area starts at the littoral plain, ranging from 500 m to 2.000 m, being continued in parts by a piedmont intercepted by a very abrupt mega-cliff, or hectares of climbing sand dunes leading to a short high plateau limited by a soft hilly area to the East. Two soil types are characteristic: Entisols (Torriorthent) covering the coastal beach sediments, and Aridisols along the cliff and adjacent hills. Vegetation consists not only of a very rich lichen cover, but also of endangered vascular species associations constituting a very fragile sub-tropical coastal desert community, such as Eulychnia, Cumulopuntia, Eriosyce cacti, and Lycium - Nolana- Ephedra communities. Fog oasis
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Heterotrophic bacteria in soils of Larsemann Oasis of East Antarctica
NASA Astrophysics Data System (ADS)
Churilin, Nikita; Soina, Vera
2015-04-01
The study of diversity and functional state of microorganisms in subsurface rocks layers, their participation in the biochemical weathering and formation of organic horizons of soils is important for understanding ecology and microorganisms in Antarctic soils. The study of cultured forms of microorganisms and their potential viability is still relevant to characterize the physiological state, biological activity and resilience of microorganisms involved in the initial soil formation. Improvement of isolation techniques of viable bacteria from the extreme habitats has a particular importance for rising the efficiency of environmental monitoring. The aim of the study was to investigate the viable heterotrophic bacteria involved in the formation of soils from wet valleys Larsemann Oasis, which is one of the warmest ice-free space of East Antarctica. Soil samples were taken from the intermountain humid valleys, where silt-gravelly substrates formed moss, algae, lichen cover. We used nutrient solutions (trypticase soy, R2A and glucose-peptone) to isolate cultured bacteria and study their morphological types in the light microscope. The total number of microorganisms was determined by fluorescent microscopy with acridine orange. SEM was used for morphological studies of bacterial communities in situ. To activate the growth processes we added into nutrient solutions various regulatory metabolites that have dose-dependence and operate at the community level. Physiological and functional conditions were determined by the duration of the lag phase and specific growth rate of bacterial communities in nutrient solutions containing various organic substrates. Soils form under protection of «stone pavement» and organisms leave the surface, so the forming organo-mineral horizon occurs inside of rock, thus the microprofile can form on both sides of the organic horizons. UV radiation, lack of moisture and strong wind are main limiting factors for microorganisms' growth in
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NASA Astrophysics Data System (ADS)
Li, Xingmin; Lu, Ling; Yang, Wenfeng; Cheng, Guodong
2012-07-01
Estimating surface evapotranspiration is extremely important for the study of water resources in arid regions. Data from the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer (NOAA/AVHRR), meteorological observations and data obtained from the Watershed Allied Telemetry Experimental Research (WATER) project in 2008 are applied to the evaporative fraction model to estimate evapotranspiration over the Heihe River Basin. The calculation method for the parameters used in the model and the evapotranspiration estimation results are analyzed and evaluated. The results observed within the oasis and the banks of the river suggest that more evapotranspiration occurs in the inland river basin in the arid region from May to September. Evapotranspiration values for the oasis, where the land surface types and vegetations are highly variable, are relatively small and heterogeneous. In the Gobi desert and other deserts with little vegetation, evapotranspiration remains at its lowest level during this period. These results reinforce the conclusion that rational utilization of water resources in the oasis is essential to manage the water resources in the inland river basin. In the remote sensing-based evapotranspiration model, the accuracy of the parameter estimate directly affects the accuracy of the evapotranspiration results; more accurate parameter values yield more precise values for evapotranspiration. However, when using the evaporative fraction to estimate regional evapotranspiration, better calculation results can be achieved only if evaporative fraction is constant in the daytime.
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National highway system connectors to freight facilities in the Delaware Valley region
DOT National Transportation Integrated Search
2001-10-01
DVRPC conducted a study of important roadway connections between the National Highway System and 12 key intermodal freight terminals (or clusters of freight facilities) to assist the planning needs of the Delaware Valley Goods Movement Task Force.
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A Progressive Black Top Hat Transformation Algorithm for Estimating Valley Volumes from DEM Data
NASA Astrophysics Data System (ADS)
Luo, W.; Pingel, T.; Heo, J.; Howard, A. D.
2013-12-01
The amount of valley incision and valley volume are important parameters in geomorphology and hydrology research, because they are related to the amount erosion (and thus the volume of sediments) and the amount of water needed to create the valley. This is not only the case for terrestrial research but also for planetary research as such figuring out how much water was on Mars. With readily available digital elevation model (DEM) data, the Black Top Hat (BTH) transformation, an image processing technique for extracting dark features on a variable background, has been applied to DEM data to extract valley depth and estimate valley volume. However, previous studies typically use one single structuring element size for extracting the valley feature and one single threshold value for removing noise, resulting in some finer features such as tributaries not being extracted and underestimation of valley volume. Inspired by similar algorithms used in LiDAR data analysis to separate above ground features and bare earth topography, here we propose a progressive BTH (PBTH) transformation algorithm, where the structuring elements size is progressively increased to extract valleys of different orders. In addition, a slope based threshold was introduced to automatically adjust the threshold values for structuring elements with different sizes. Connectivity and shape parameters of the masked regions were used to keep the long linear valleys while removing other smaller non-connected regions. Preliminary application of the PBTH to Grand Canyon and two sites on Mars has produced promising results. More testing and fine-tuning is in progress. The ultimate goal of the project is to apply the algorithm to estimate the volume of valley networks on Mars and the volume of water needed to form the valleys we observe today and thus infer the nature of the hydrologic cycle on early Mars. The project is funded by NASA's Mars Data Analysis program.
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NASA Astrophysics Data System (ADS)
Menendez, H. M.; Thurber, C. H.
2011-12-01
Eastern California's Long Valley Caldera (LVC) and the Mono-Inyo Crater volcanic systems have been active for the past ~3.6 million years. Long Valley is known to produce very large silicic eruptions, the last of which resulted in the formation of a 17 km by 32 km wide, east-west trending caldera. Relatively recent unrest began between 1978-1980 with five ML ≥ 5.7 non-double-couple (NDC) earthquakes and associated aftershock swarms. Similar shallow seismic swarms have continued south of the resurgent dome and beneath Mammoth Mountain, surrounding sites of increased CO2 gas emissions. Nearly two decades of increased volcanic activity led to the 1997 installation of a temporary three-component array of 69 seismometers. This network, deployed by the Durham University, the USGS, and Duke University, recorded over 4,000 high-frequency events from May to September. A local tomographic inversion of 283 events surrounding Mammoth Mountain yielded a velocity structure with low Vp and Vp/Vs anomalies at 2-3 km bsl beneath the resurgent dome and Casa Diablo hot springs. These anomalies were interpreted to be CO2 reservoirs (Foulger et al., 2003). Several teleseismic and regional tomography studies have also imaged low Vp anomalies beneath the caldera at ~5-15 km depth, interpreted to be the underlying magma reservoir (Dawson et al., 1990; Weiland et al., 1995; Thurber et al., 2009). This study aims to improve the resolution of the LVC regional velocity model by performing tomographic inversions using the local events from 1997 in conjunction with regional events recorded by the Northern California Seismic Network (NCSN) between 1980 and 2010 and available refraction data. Initial tomographic inversions reveal a low velocity zone at ~2 to 6 km depth beneath the caldera. This structure may simply represent the caldera fill. Further iterations and the incorporation of teleseismic data may better resolve the overall shape and size of the underlying magma reservoir.
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NASA Astrophysics Data System (ADS)
Prejean, Stephanie; Ellsworth, William; Zoback, Mark; Waldhauser, Felix
2002-12-01
We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (˜20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.
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Prejean, Stephanie; Ellsworth, William L.; Zoback, Mark; Waldhauser, Felix
2002-01-01
We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (???20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.
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NASA Astrophysics Data System (ADS)
Barman, Prakash; Jade, Sridevi; Shrungeshwara, T. S.; Kumar, Ashok; Bhattacharyya, Sanjeev; Ray, Jagat Dwipendra; Jagannathan, Saigeetha; Jamir, Wangshi Menla
2017-09-01
The present study reports the contemporary deformation of the tectonically complex northeast India using 11 years (2002-2013) of GPS observations. The central Shillong Plateau and few sites north of Plateau located in Assam Valley behave like a rigid block with 7 mm/year India-fixed southward velocity. The Euler pole of rotation of this central Shillong Plateau-Assam Valley (SH-AS) block is estimated to be at -25.1° ± 0.2°N, -97.8° ± 1.8°E with an angular velocity of 0.533° ± 0.10° Myr-1 relative to India-fixed reference frame. Kopili fault located between Shillong Plateau and Mikir massif records a dextral slip of 4.7 ± 1.3 mm/year with a locking depth of 10.2 ± 1.4 km indicating the fragmentation of Assam Valley across the fault. Presently, western edge of Mikir massif appears to be locked to Assam block indicating strain accumulation in this region. First-order elastic dislocation modelling of the GPS velocities estimates a slip rate of 16 mm/year along the Main Himalayan Thrust in Eastern Himalaya which is locked over a width of 130 km from the surface to a depth of 17 km with underthrusting Indian plate. Around 9 mm/year arc-normal convergence is accommodated in Lesser Himalaya just south of Main Central Thrust indicating high strain accumulation. Out of 36 mm/year (SSE) India-Sunda plate motion, about 16 mm/year motion is accommodated in Indo-Burmese Fold and Thrust Belt, both as normal convergence ( 6 mm/year) and active slip ( 7-11 mm/year) in this region.
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NASA Technical Reports Server (NTRS)
Huang, Jonathan; Hoover, Richard B.; Swain, Ashit; Murdock, Chris; Bej, Asim K.
2010-01-01
Extreme conditions such as low temperature, dryness, and constant UV-radiation in terrestrial Antarctica are limiting factors of the survival of microbial populations. The objective of this study was to investigate the microbial diversity and enumeration between the open water lakes of Schirmacher Oasis and the permanently ice-covered Lake Untersee. The lakes in Schirmacher Oasis possessed abundant and diverse group of microorganisms compared to the Lake Untersee. Furthermore, the microbial diversity between two lakes in Schirmacher Oasis (Lake L27C and L47) was compared by culture-based molecular approach. It was determined that L27Chad a richer microbial diversity representing 5 different phyla and 7 different genera. In contrast L47 consisted of 4 different phyla and 6 different genera. The difference in microbial community could be due to the wide range of pH between L27C (pH 9.1) and L47 (pH 5.7). Most of the microbes isolated from these lakes consisted of adaptive biological pigmentation. Characterization of the microbial community found in the freshwater lakes of East Antarctica is important because it gives a further glimpse into the adaptation and survival strategies found in extreme conditions.
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NASA Astrophysics Data System (ADS)
Watanabe, Makiko; Koizumi, Natsuko; Kato, Sayuri; Kikuchi, Ryohei; Kamei, Hiroyuki
2014-05-01
Desertification in North Africa has rapidly advanced over the last 6,000 years. Such environmental changes began in the Early Dynastic Period of Egypt (4200 - 3150 BC), and the occupation of Achaemenid Persian and Roman cultures in Egypt occurred under even drier climates. Kharga is the largest oasis of the five oases, located in the western desert of Egypt that contains a treasure trove of archaeological resources. This oasis has been highlighted to promote resource exploration and development of archaeological tourism since the 1980's. The El-Zayyan temple is located 27 km south of the central Kharga oasis. Zayyan was once called 'Tchonemyris', which has connection with the means of 'huge well' in Greek. Although major portions of the temple were rebuilt in 140 AD during the rule of the Roman Emperor Antoninus Pius, this temple is considered to be originally built in the Ptolemaic period (4c-1c BC). It is likely that the area had a sufficient water supply in the past as the El-Zayyan temple stands at the lowest point (-18 m a.s.l.) in the Kharga oasis. Furthermore, the El-Ghueita temple that stands on a hill top at 68.5 m a.s.l., 4 km northward from the El-Zayyan temple, has given name that means 'beautiful garden' in Greek. From these facts, we can imagine that the past landscape of this area contained green surroundings. The El-Ghueita temple was well known as a production centre of high quality wine since the mid-Dynastic age (2050 -1786 BC). As this area is currently arid, it is expected that there were irrigation facilities to maintain the vast farm land during the ancient period. To deepen our knowledge of how people developed their technologies and conducted their life within the natural environment of a drastic drying period, understanding the process of environmental change on a region scale is necessary. The aim of this study was to extract proxies from sand deposits in the western desert area to estimate the change in the environment. We examined the
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-05
... Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National Park, Inyo... an Environmental Impact Statement for the Saline Valley Warm Springs Management Plan, Death Valley... analysis process for the Saline Valley Warm Springs Management Plan for Death Valley [[Page 33238...
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2014-01-01
Background This paper represents the first ethnobotanical study in Chail valley of district Swat-Pakistan and provides significant information on medicinal plants use among the tribal people of the area. The aim of this study was to document the medicinal uses of local plants and to develop an ethnobotanical inventory of the species diversity. Methods In present study, semi-structured interviews with 142 inhabitants (age range between 31–75 years) were conducted. Ethnobotanical data was analyzed using relative frequency of citation (RFC) to determine the well-known and most useful species in the area. Results Current research work reports total of 50 plant species belonging to 48 genera of 35 families from Chail valley. Origanum vulgare, Geranium wallichianum and Skimmia laureola have the highest values of relative frequency of citation (RFC) and are widely known by the inhabitants of the valley. The majority of the documented plants were herbs (58%) followed by shrubs (28%), trees (12%) and then climbers (2%). The part of the plant most frequently used was the leaves (33%) followed by roots (17%), fruits (14%), whole plant (12%), rhizomes (9%), stems (6%), barks (5%) and seeds (4%). Decoction was the most common preparation method use in herbal recipes. The most frequently treated diseases in the valley were urinary disorders, skin infections, digestive disorders, asthma, jaundice, angina, chronic dysentery and diarrhea. Conclusion This study contributes an ethnobotanical inventory of medicinal plants with their frequency of citations together with the part used, disease treated and methods of application among the tribal communities of Chail valley. The present survey has documented from this valley considerable indigenous knowledge about the local medicinal plants for treating number of common diseases that is ready to be further investigated for biological, pharmacological and toxicological screening. This study also provides some socio-economic aspects which
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77 FR 18879 - Meeting of the Regional Resource Stewardship Council
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-28
... TENNESSEE VALLEY AUTHORITY Meeting of the Regional Resource Stewardship Council AGENCY: Tennessee Valley Authority (TVA). ACTION: Notice of meeting. SUMMARY: The TVA Regional Resource Stewardship Council... Stewardship Council, Tennessee Valley Authority, 400 West Summit Hill Drive, WT-11 B, Knoxville, Tennessee...
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Geophysical setting of the Wabash Valley fault system
Hildenbrand, T.G.; Ravat, D.
1997-01-01
Interpretation of existing regional magnetic and gravity data and new local high-resolution aeromagnetic data provides new insights on the tectonic history and structural development of the Wabash Valley Fault System in Illinois and Indiana. Enhancement of short-wavelength magnetic anomalies reveal numerous NW- to NNE-trending ultramafic dikes and six intrusive complexes (including those at Hicks Dome and Omaha Dome). Inversion models indicate that the interpreted dikes are narrow (???3 m), lie at shallow depths (500 km long and generally >50 km wide) and with deep basins (locally >3 km thick), the ancestral Wabash Valley faults express, in comparison, minor tectonic structures and probably do not represent a failed rift arm. There is a lack of any obvious relation between the Wabash Valley Fault System and the epicenters of historic and prehistoric earthquakes. Five prehistoric earthquakes lie conspicuously near structures associated with the Commerce geophysical lineament, a NE-trending magnetic and gravity lineament lying oblique to the Wabash Valley Fault System and possibly extending over 600 km from NE Arkansas to central Indiana.
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NASA Astrophysics Data System (ADS)
Li, H.; Dong, G.; Zhang, S.
2017-12-01
Many ancient cities and settlement sites have been found in Lucaogou, an ancient oasis near Dunhuangcity in northwest China. These settlements indicate that humans inhabited this area during the historicalperiod. However, the chronology and subsistence practices of this area remain unclear. Based on newdata from radiocarbon dating, macrobotanical analysis, and the synthesis of historical documents andhigh-resolution paleoclimatic records, we discuss the inter-relationship between human settlements andplant resource utilization strategies at Lucaogou ancient oasis during historical period. Our resultsindicate that these ancient sites in Lucaogou area were built between the Han dynasty (202 BC-AD 220)and the Ming dynasty (AD 1368-AD 1644). People mainly used foxtail millet, broomcorn millet, barleyand three types of wood (Tamarix, Salix, Populus), probably as fuel for cooking. Human settlement intensityin the area during the historical period was primarily influenced by political situations, whichmight also have been affected by fluctuations in precipitation.
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An exploration of adult body shape and limb proportions at Kellis 2, Dakhleh Oasis, Egypt.
Bleuze, Michele M; Wheeler, Sandra M; Dupras, Tosha L; Williams, Lana J; El Molto, J
2014-03-01
Several studies have shown that the human body generally conforms to the ecogeographical expectations of Bergmann's and Allen's rules; however, recent evidence suggests that these expectations may not hold completely for some populations. Egypt is located at the crossroads of Sub-Saharan Africa, Southern Europe, and the Near East, and gene flow among groups in these regions may confound ecogeographical patterning. In this study, we test the fit of the adult physique of a large sample (N = 163) of females and males from the Kellis 2 cemetery (Dakhleh Oasis, Egypt) against ecogeographical predictions. Body shape (i.e., body mass relative to stature) was assessed by the femur head diameter to bicondylar femur length index (FHD/BFL), and brachial and crural indices were calculated to examine intralimb proportions. Body shape in the Kellis 2 sample is not significantly different from high-latitude groups and a Lower Nubian sample, and intralimb proportions are not significantly different from mid-latitude and other low-latitude groups. This study demonstrates the potential uniqueness of body shape and intralimb proportions in an ancient Egyptian sample, and further highlights the complex relationship between ecogeographic patterning and adaptation. Copyright © 2013 Wiley Periodicals, Inc.
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Valley floor climate observations from the McMurdo dry valleys, Antarctica, 1986-2000
Doran, P.T.; McKay, C.P.; Clow, G.D.; Dana, G.L.; Fountain, A.G.; Nylen, T.; Lyons, W.B.
2002-01-01
Climate observations from the McMurdo dry valleys, East Antarctica are presented from a network of seven valley floor automatic meteorological stations during the period 1986 to 2000. Mean annual temperatures ranged from -14.8??C to -30.0??C, depending on the site and period of measurement. Mean annual relative humidity is generally highest near the coast. Mean annual wind speed increases with proximity to the polar plateau. Site-to-site variation in mean annual solar flux and PAR is due to exposure of each station and changes over time are likely related to changes in cloudiness. During the nonsummer months, strong katabatic winds are frequent at some sites and infrequent at others, creating large variation in mean annual temperature owing to the warming effect of the winds. Katabatic wind exposure appears to be controlled to a large degree by the presence of colder air in the region that collects at low points and keeps the warm less dense katabatic flow from the ground. The strong influence of katabatic winds makes prediction of relative mean annual temperature based on geographical position (elevation and distance from the coast) alone, not possible. During the summer months, onshore winds dominate and warm as they progress through the valleys creating a strong linear relationship (r2 = 0.992) of increasing potential temperature with distance from the coast (0.09??C km-1). In contrast to mean annual temperature, summer temperature lends itself quite well to model predictions, and is used to construct a statistical model for predicting summer dry valley temperatures at unmonitored sites. Copyright 2002 by the American Geophysical Union.
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Revisiting the 1872 Owens Valley, California, Earthquake
Hough, S.E.; Hutton, K.
2008-01-01
The 26 March 1872 Owens Valley earthquake is among the largest historical earthquakes in California. The felt area and maximum fault displacements have long been regarded as comparable to, if not greater than, those of the great San Andreas fault earthquakes of 1857 and 1906, but mapped surface ruptures of the latter two events were 2-3 times longer than that inferred for the 1872 rupture. The preferred magnitude estimate of the Owens Valley earthquake has thus been 7.4, based largely on the geological evidence. Reinterpreting macroseismic accounts of the Owens Valley earthquake, we infer generally lower intensity values than those estimated in earlier studies. Nonetheless, as recognized in the early twentieth century, the effects of this earthquake were still generally more dramatic at regional distances than the macroseismic effects from the 1906 earthquake, with light damage to masonry buildings at (nearest-fault) distances as large as 400 km. Macroseismic observations thus suggest a magnitude greater than that of the 1906 San Francisco earthquake, which appears to be at odds with geological observations. However, while the mapped rupture length of the Owens Valley earthquake is relatively low, the average slip was high. The surface rupture was also complex and extended over multiple fault segments. It was first mapped in detail over a century after the earthquake occurred, and recent evidence suggests it might have been longer than earlier studies indicated. Our preferred magnitude estimate is Mw 7.8-7.9, values that we show are consistent with the geological observations. The results of our study suggest that either the Owens Valley earthquake was larger than the 1906 San Francisco earthquake or that, by virtue of source properties and/or propagation effects, it produced systematically higher ground motions at regional distances. The latter possibility implies that some large earthquakes in California will generate significantly larger ground motions than San
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Fracture controls on valley persistence: the Cairngorm Granite pluton, Scotland
NASA Astrophysics Data System (ADS)
Hall, A. M.; Gillespie, M. R.
2017-09-01
Valleys are remarkably persistent features in many different tectonic settings, but the reasons for this persistence are rarely explored. Here, we examine the structural controls on valleys in the Cairngorms Mountains, Scotland, part of the passive margin of the eastern North Atlantic. We consider valleys at three scales: straths, glens and headwater valleys. The structural controls on valleys in and around the Cairngorm Granite pluton were examined on satellite and aerial photographs and by field survey. Topographic lineaments, including valleys, show no consistent orientation with joint sets or with sheets of microgranite and pegmatitic granite. In this granite landscape, jointing is not a first-order control on valley development. Instead, glens and headwater valleys align closely to quartz veins and linear alteration zones (LAZs). LAZs are zones of weakness in the granite pluton in which late-stage hydrothermal alteration and hydro-fracturing have greatly reduced rock mass strength and increased permeability. LAZs, which can be kilometres long and >700 m deep, are the dominant controls on the orientation of valleys in the Cairngorms. LAZs formed in the roof zone of the granite intrusion. Although the Cairngorm pluton was unroofed soon after emplacement, the presence of Old Red Sandstone (ORS) outliers in the terrain to the north and east indicates that the lower relief of the sub-ORS basement surface has been lowered by <500 m. Hence, the valley patterns in and around the Cairngorms have persisted through >1 km of vertical erosion and for 400 Myr. This valley persistence is a combined product of regionally low rates of basement exhumation and of the existence of LAZs in the Cairngorm pluton and sub-parallel Caledonide fractures in the surrounding terrain with depths that exceed 1 km.
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27 CFR 9.57 - Green Valley of Russian River Valley.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...
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27 CFR 9.57 - Green Valley of Russian River Valley.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...
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27 CFR 9.57 - Green Valley of Russian River Valley.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...
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27 CFR 9.57 - Green Valley of Russian River Valley.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...
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27 CFR 9.57 - Green Valley of Russian River Valley.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Green Valley of Russian River Valley. 9.57 Section 9.57 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.57 Green Valley of Russian River...
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Winter fog is decreasing in the fruit growing region of the Central Valley of California
NASA Astrophysics Data System (ADS)
Baldocchi, Dennis; Waller, Eric
2014-05-01
The Central Valley of California is home to a variety of fruit and nut trees. These trees account for 95% of the U.S. production, but they need a sufficient amount of winter chill to achieve rest and quiescence for the next season's buds and flowers. In prior work, we reported that the accumulation of winter chill is declining in the Central Valley. We hypothesize that a reduction in winter fog is cooccurring and is contributing to the reduction in winter chill. We examined a 33 year record of satellite remote sensing to develop a fog climatology for the Central Valley. We find that the number of winter fog events, integrated spatially, decreased 46%, on average, over 32 winters, with much year to year variability. Less fog means warmer air and an increase in the energy balance on buds, which amplifies their warming, reducing their chill accumulation more.
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NASA Technical Reports Server (NTRS)
Mittlefehldt, D. W.; Gellert, R.; Van Bommel, S.; Arvidson, R. E.; Clark, B. C.; Ming, D. W.; Schroeder, C.; Yen, A. S.; Fox, V. K.; Farrand, W. H.;
2016-01-01
Mars Exploration Rover Opportunity has been exploring Mars for 12+ years, and is presently investigating the geology of a western rim segment of 22 kilometers diameter, Noachian- aged Endeavour crater. The Alpha Particle X-ray Spectrometer has determined the compositions of a pre-impact lithology, the Matijevic fm., and polymict impact breccias ejected from the crater, the Shoemaker fm. Opportunity is now investigating a region named Marathon Valley that cuts southwest-northeast through the central portion of the rim segment and provides a window into the lower stratigraphic record. (Geographic names used here are informal.) At the head of Marathon Valley, referred to here as Upper Marathon Valley, is a shallow, ovoid depression approximately 25×35 millimeters in size, named Spirit of Saint Louis. Layering inside Spirit of Saint Louis appears continuous with the Upper Marathon Valley rocks outside, indicating they are coeval. Spirit of Saint Louis is partly bounded by approximately 10-20 centimeters wide zone containing reddish altered rocks (red zone). Red zones also form prominent curvilinear features in Marathon Valley. Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) spectra provide evidence for a really extensive Fe-Mg smectite in the Marathon Valley region, indicating distinct styles of aqueous alteration. The CRISM detections of smectites are based on metal-OH absorptions at approximately 2.3 and 2.4 micron that are at least two times the background noise level.
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Farmer, G.L.; Broxton, D.E.; Warren, R.G.; Pickthorn, W.
1991-01-01
Nd, Sr and O isotopic data were obtained from silicic ash-flow tuffs and lavas at the Tertiary age (16-9 Ma) Timber (Mountain/Oasis Valley volcanic center (TMOV) in southern Nevada, to assess models for the origin and evolution of the large-volume silicic magma bodies generated in this region. The large-volume (>900 km3), chemically-zoned, Topopah Spring (TS) and Tiva Canyon (TC) members of the Paintbrush Tuff, and the Rainier Mesa (RM) and Ammonia Tanks (AT) members of the younger Timber Mountain Tuff all have internal Nd and Sr isotopic zonations. In each tuff, high-silica rhyolites have lower initial e{open}Nd values (???1 e{open}Nd unit), higher87Sr/86Sr, and lower Nd and Sr contents, than cocrupted trachytes. The TS, TC, and RM members have similar e{open}Nd values for high-silica rhyolites (-11.7 to -11.2) and trachytes (-10.5 to -10.7), but the younger AT member has a higher e{open}Nd for both compositional types (-10.3 and -9.4). Oxygen isotope data confirm that the TC and AT members were derived from low e{open}Nd magmas. The internal Sr and Nd isotopic variations in each tuff are interpreted to be the result of the incorporation of 20-40% (by mass) wall-rock into magmas that were injected into the upper crust. The low e{open}Nd magmas most likely formed via the incorporation of low ??18O, hydrothermally-altered, wall-rock. Small-volume rhyolite lavas and ash-flow tuffs have similar isotopic characteristics to the large-volume ash-flow tuffs, but lavas erupted from extracaldera vents may have interacted with higher ??18O crustal rocks peripheral to the main magma chamber(s). Andesitic lavas from the 13-14 Ma Wahmonie/Salyer volcanic center southeast of the TMOV have low e{open}Nd (-13.2 to -13.8) and are considered on the basis of textural evidence to be mixtures of basaltic composition magmas and large proportions (70-80%) of anatectic crustal melts. A similar process may have occurred early in the magmatic history of the TMOV. The large-volume rhyolites
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NASA Technical Reports Server (NTRS)
Kochel, R. Craig; Piper, Jonathan F.
1986-01-01
Morphometric data on the runoff and sapping valleys on the slopes of Hawaii and Molokai in Hawaii are analyzed. The analysis reveals a clear distinction between the runoff valleys and sapping valleys. The Hawaiian sapping valleys are characterized by: (1) steep valley walls and flat floors, (2) amphitheater heads, (3) low drainage density, (4) paucity of downstream tributaries, (5) low frequency of up-dip tributaries, and (6) structural and stratigraphic control on valley patterns. The characteristics of the Hawaiian sapping valleys are compared to Martian valleys and experimental systems, and good correlation between the data is detected. Flume experiments were also conducted to study the evolution of sapping valleys in response to variable structure and stratigraphy.
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Structural superposition in fault systems bounding Santa Clara Valley, California
Graymer, Russell W.; Stanley, Richard G.; Ponce, David A.; Jachens, Robert C.; Simpson, Robert W.; Wentworth, Carl M.
2015-01-01
Santa Clara Valley is bounded on the southwest and northeast by active strike-slip and reverse-oblique faults of the San Andreas fault system. On both sides of the valley, these faults are superposed on older normal and/or right-lateral normal oblique faults. The older faults comprised early components of the San Andreas fault system as it formed in the wake of the northward passage of the Mendocino Triple Junction. On the east side of the valley, the great majority of fault displacement was accommodated by the older faults, which were almost entirely abandoned when the presently active faults became active after ca. 2.5 Ma. On the west side of the valley, the older faults were abandoned earlier, before ca. 8 Ma and probably accumulated only a small amount, if any, of the total right-lateral offset accommodated by the fault zone as a whole. Apparent contradictions in observations of fault offset and the relation of the gravity field to the distribution of dense rocks at the surface are explained by recognition of superposed structures in the Santa Clara Valley region.
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Airborne electromagnetic and magnetic survey data of the Paradox and San Luis Valleys, Colorado
Ball, Lyndsay B.; Bloss, Benjamin R.; Bedrosian, Paul A.; Grauch, V.J.S.; Smith, Bruce D.
2015-01-01
In October 2011, the U.S. Geological Survey (USGS) contracted airborne magnetic and electromagnetic surveys of the Paradox and San Luis Valleys in southern Colorado, United States. These airborne geophysical surveys provide high-resolution and spatially comprehensive datasets characterizing the resistivity structure of the shallow subsurface of each survey region, accompanied by magnetic-field information over matching areas. These data were collected to provide insight into the distribution of groundwater brine in the Paradox Valley, the extent of clay aquitards in the San Luis Valley, and to improve our understanding of the geologic framework for both regions. This report describes these contracted surveys and releases digital data supplied under contract to the USGS.
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McLaughlin, R.J.; Langenheim, V.E.; Schmidt, K.M.; Jachens, R.C.; Stanley, R.G.; Jayko, A.S.; McDougall, K.A.; Tinsley, J.C.; Valin, Z.C.
1999-01-01
In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly understood. Based on recent geologic mapping and geophysical investigations, we propose that the range-front thrust system evolved in conjunction with development of the San Andreas fault system. In the early Miocene, the region was dominated by a system of northwestwardly propagating, basin-bounding, transtensional faults. Beginning as early as middle Miocene time, however, the transtensional faulting was superseded by transpressional NE-stepping thrust and reverse faults of the range-front thrust system. Age constraints on the thrust faults indicate that the locus of contraction has focused on the Monte Vista, Shannon, and Berrocal faults since about 4.8 Ma. Fault slip and fold reconstructions suggest that crustal shortening between the San Andreas fault and the Santa Clara Valley within this time frame is ~21%, amounting to as much as 3.2 km at a rate of 0.6 mm/yr. Rates probably have not remained constant; average rates appear to have been much lower in the past few 100 ka. The distribution of coseismic surface contraction during the Loma Prieta earthquake, active seismicity, late Pleistocene to Holocene fluvial terrace warping, and geodetic data further suggest that the active range-front thrust system includes blind thrusts. Critical unresolved issues include information on the near-surface locations of buried thrusts, the timing of recent thrust earthquake events, and their recurrence in relation to earthquakes on the San Andreas fault.
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Modelling the effect of buried valleys on groundwater flow: case study in Ventspils vicinity, Latvia
NASA Astrophysics Data System (ADS)
Delina, Aija; Popovs, Konrads; Bikse, Janis; Retike, Inga; Babre, Alise; Kalvane, Gunta
2015-04-01
Buried subglacial valleys are widely distributed in glaciated regions and they can have great influence on groundwater flow and hence on groundwater resources. The aim of this study is to evaluate the effect of the buried valleys on groundwater flow in a confined aquifer (Middle Devonian Eifelian stage Arukila aquifer, D2ar) applying numerical modelling. The study area is located at vicinity of Ventspils Town, near wellfield Ogsils where number of the buried valleys with different depth and filling material are present. Area is located close to the Baltic Sea at Piejūra lowland Rinda plain and regional groundwater flow is towards sea. Territory is covered by thin layer of Quaternary sediments in thicknesses of 10 to 20 meters although Prequaternary sediments are exposed at some places. Buried valleys are characterized as narrow, elongated and deep formations that is be filled with various, mainly Pleistocene glacigene sediments - either till loam of different ages or sand and gravel or interbedding of both above mentioned. The filling material of the valleys influences groundwater flow in the confined aquifers which is intercepted by the valleys. It is supposed that glacial till loam filled valleys serves as a barrier to groundwater flow and as a recharge conduit when filled with sand and gravel deposits. Numerical model was built within MOSYS modelling system (Virbulis et al. 2012) using finite element method in order to investigate buried valley influence on groundwater flow in the study area. Several conceptual models were tested in numerical model depending on buried valley filling material: sand and gravel, till loam or mixture of them. Groundwater flow paths and travel times were studied. Results suggested that valley filled with glacial till is acting as barrier and it causes sharp drop of piezometric head and downward flow. Valley filled with sand and gravel have almost no effect on piezometric head distribution, however it this case buried valleys
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Businessman's Efforts Help Reinvent Valley Tech
ERIC Educational Resources Information Center
Pedersen, Diane B.
2007-01-01
Machine shop and metal fabrication programs across the country have struggled since the mid-1980s when the rise in global competition resulted in more manufacturing jobs going overseas. Blackstone Valley Regional Vocational Technical High School in Upton, Massachusetts, was able to keep its program up and running due in large part to its…
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Venusian channels and valleys - Distribution and volcanological implications
NASA Technical Reports Server (NTRS)
Komatsu, Goro; Baker, Victor R.; Gulick, Virginia C.; Parker, Timothy J.
1993-01-01
An updated map is presented which shows the distribution of more than 200 channels and valleys on Venus. A large number of channels are concentrated in equatorial regions characterized by highlands, rift and fracture zones, an associated volcanic features. Many channels associated with flow deposits are similar to typical terrestrial lava drainage channels. They are associated with a wide range of volcanic edifices. More than half of the sinuous rilles are associated with coronae, coronalike features, or arachnoids. Corona volcanism driven by mantle plume events may explain this association. Many valley network are observed in highlands and in association with coronae, coronalike features, or arachnoids. This indicates that highlands and coronae provided fractures and flow-viscosity lavas, both of which seem to be required for network formation by lava sapping processes. Canali-type channels have a unique distribution limited to some plains regions.
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The combined Fog Monitoring System of ARPAV over the Veneto Region, Po Valley - Italy
NASA Astrophysics Data System (ADS)
Domenichini, F.; Rossa, A.; Zardini, F.; Monai, M.; Calza, M.; Della Valle, A.; Gaspari, V.
2010-07-01
The presence of fog is a frequent problem in the Po Valley. The consequent reduction in visibility has a strong impact on the road, air, ship and railway traffic. Both, fog monitoring and forecasting, constitute significant challenges, not least due to the high spatial and temporal variability of the phenomenon. ARPAV (Regional Agency for Environmental Prevention and Protection of Veneto) is the regional meteorological service of the north-eastern Italian region Veneto and, as such, is responsible for meteorological support to institutional and private users. Real-time visibility information over an extended area would represent an interesting product for road and transport safety. In the framework of the FP7 project Roadidea, (14 partners from 8 different countries, Dec 2007 - Aug 2010) on road safety and traffic control ARPAV developed pilot system for the fog monitoring. The main idea of this fog monitoring methodology is to merge information derived from different observation platforms, i.e. satellite low stratus cloud classification, direct visibility monitoring, statistical estimation of low visibility from meteorological parameters at the ground. This information is translated into probability maps of fog occurrence and information weight on a common grid (4x4 km) covering the flat portion of the region Veneto. These weights are used to combine the three data sources into the final fog probability map. A probabilistic verification applied to the fog monitoring product yields encouraging results, and is systematically more skillfull than the fog probabilities derived from the individual data sources. First real-time products are now available on the ARPAV Fog Pilot website for a group of specific users (motorway head office, road police, national railways and others) and are under testing.
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Water resources of Beaver Valley, Utah
Lee, Willis Thomas
1908-01-01
Location and extent of area examined. Beaver Valley is located in Beaver County, in southwestern Utah, about 175 miles south of Salt Lake. It lies between the Tushar Mountains on the east and the Beaver Mountains on the west. The principal town of the valley is Beaver, which is most conveniently reached from Milford, a station on the San Pedro, Los Angeles and Salt Lake Railroad. The valley, together with its neighboring highlands, occupies the eastern third of Beaver County, an area of about 1,200 square miles. A large part of this area, however, is rocky upland and unproductive desert, the tillable land comprising a comparatively small area in the immediate vicinity of the streams.Purpose and scope of work. The purpose of this paper is to present information concerning the waters of Beaver Valley and to point out ways and means of increasing their usefulness. The presence of a large amount of water in Beaver Valley results from local topograhic conditions, the water being supplied by precipitation in the highland to the east. Its conservation and distribution result from geologic conditions, the water being held in loose gravel and sand, which are more or less confined between ridges of consolidated rocks. The rock basins were formed partly by erosion and partly by faulting and surface deformation. In order to accomplish the purpose in view it is therefore necessary to describe the geographic and geologic conditions in Beaver Valley and neighboring regions.The investigation included the determination of the flow of streams and springs, of the manner of occurrence and quantity of the underground waters as shown by the geologic and geographic conditions of the region and by the distribution of springs and wells, and of the chemical character of the waters with reference to their adaptability to domestic use and to irrigation. The chemical data were obtained (a) by field assays, which are approximately correct and probably of sufficient accuracy to be of value in
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Crist
2005-10-02
Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, is evaluating the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury, arsenic, and associated fine particulate matter. This evaluation will involve two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring will include the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station will contain sampling equipment tomore » collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), arsenic, particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NOx, SO{sub 2}, O{sub 3}, etc.). Laboratory analysis of time-integrated samples will be used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Near-real-time measurements will be used to measure the ambient concentrations of PM mass and all gaseous species including Hg{sup 0} and RGM. Approximately of 18 months of field data will be collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data will also provide mercury, arsenic, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis will include (1) development of updated inventories of mercury and arsenic emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg0, RGM, arsenic, and fine
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Crist
2006-04-02
As stated in the proposal: Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, is evaluating the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury, arsenic, and associated fine particulate matter. This evaluation will involve two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring will include the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM stationmore » will contain sampling equipment to collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), arsenic, particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NO{sub x}, SO{sub 2}, O{sub 3}, etc.). Laboratory analysis of time-integrated samples will be used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Near-real-time measurements will be used to measure the ambient concentrations of PM mass and all gaseous species including Hg0 and RGM. Approximately 18 months of field data will be collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data will also provide mercury, arsenic, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis will include (1) development of updated inventories of mercury and arsenic emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Crist
2005-04-02
Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, is evaluating the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury, arsenic, and associated fine particulate matter. This evaluation will involve two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring will include the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station will contain sampling equipment tomore » collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), arsenic, particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NO{sub x}, SO{sub 2}, O{sub 3}, etc.). Laboratory analysis of time-integrated samples will be used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Near-real-time measurements will be used to measure the ambient concentrations of PM mass and all gaseous species including Hg{sup 0} and RGM. Approximately of 18 months of field data will be collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data will also provide mercury, arsenic, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis will include (1) development of updated inventories of mercury and arsenic emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg{sup 0}, RGM
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kevin Crist
2004-10-02
Ohio University, in collaboration with CONSOL Energy, Advanced Technology Systems, Inc (ATS) and Atmospheric and Environmental Research, Inc. (AER) as subcontractors, is evaluating the impact of emissions from coal-fired power plants in the Ohio River Valley region as they relate to the transport and deposition of mercury, arsenic, and associated fine particulate matter. This evaluation will involve two interrelated areas of effort: ambient air monitoring and regional-scale modeling analysis. The scope of work for the ambient air monitoring will include the deployment of a surface air monitoring (SAM) station in southeastern Ohio. The SAM station will contain sampling equipment tomore » collect and measure mercury (including speciated forms of mercury and wet and dry deposited mercury), arsenic, particulate matter (PM) mass, PM composition, and gaseous criteria pollutants (CO, NOx, SO{sub 2}, O{sub 3}, etc.). Laboratory analysis of time-integrated samples will be used to obtain chemical speciation of ambient PM composition and mercury in precipitation. Near-real-time measurements will be used to measure the ambient concentrations of PM mass and all gaseous species including Hg{sup 0} and RGM. Approximately of 18 months of field data will be collected at the SAM site to validate the proposed regional model simulations for episodic and seasonal model runs. The ambient air quality data will also provide mercury, arsenic, and fine particulate matter data that can be used by Ohio Valley industries to assess performance on multi-pollutant control systems. The scope of work for the modeling analysis will include (1) development of updated inventories of mercury and arsenic emissions from coal plants and other important sources in the modeled domain; (2) adapting an existing 3-D atmospheric chemical transport model to incorporate recent advancements in the understanding of mercury transformations in the atmosphere; (3) analyses of the flux of Hg{sup 0}, RGM, arsenic, and
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Spectrum of Rift Valley Fever Virus Transmission in Kenya: Insights from three Distinct Regions
Labeaud, A. Desiree; Ochiai, Yoshitsugu; Peters, C.J.; Muchiri, Eric M.; King, Charles H.
2008-01-01
Rift Valley fever virus (RVFV) is an emerging pathogen that maintains high biodefense priority based on its threat to livestock, its ability to cause human hemorrhagic fever, and its potential for aerosol spread. To define the range of human transmission during inter-epidemic and epidemic periods in Kenya, we tested archived sera from defined populations (N = 1,263) for anti-RVFV IgG by ELISA and plaque reduction neutralization testing. RVFV seroprevalence was 10.8% overall and varied significantly by location, sex, and age. In NW Kenya, high seroprevalence among those born before 1980 indicates that an undetected epidemic may have occurred then. Seroconversion documented in highland areas suggests previously unsuspected inter-epidemic transmission. RVFV seroprevalence is strikingly high in certain Kenyan areas, suggesting endemic transmission patterns that may preclude accurate estimation of regional acute outbreak incidence. The extent of both epidemic and inter-epidemic RVFV transmission in Kenya is greater than previously documented. PMID:17488893
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Influence of southwest monsoons in the Kashmir Valley, western Himalayas.
Jeelani, Ghulam; Deshpande, Rajendrakumar D; Shah, Rouf A; Hassan, Wasim
2017-08-01
The regional climate of the Himalayas is predominated by the southwest monsoons and the western disturbances. The uplift of the Pir Panjal to its present height is believed to restrict the southwest monsoons from entering into the Kashmir Valley in the western Himalayas. In the present study, monthly precipitation samples were collected across the Kashmir Valley from June 2013 to May 2014 for δ 18 O and δ 2 H analyses to constrain the influence of southwest monsoons in the valley. Except in August, the precipitation is enriched in 18 O and 2 H from June to September and depleted from October to May. The sharp depletion of 18 O in precipitation along with the decrease in d-excess in August confirm the maximum intrusion of southwest monsoons into the valley. A significant temperature - δ 18 O relationship was found during October and May (westerlies period) decreasing during June and September (southwest monsoon period). The local meteoric water line for the whole Kashmir Valley based on the precipitation-weighted monthly samples is [Formula: see text] [Formula: see text]. Higher intercept of the regression equation suggested dominant contribution of precipitation from western disturbances. The study suggested that the southwest monsoons enter the Kashmir Valley from southwest through the mountainous passes.
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Switching effects and spin-valley Andreev resonant peak shifting in silicene superconductor
NASA Astrophysics Data System (ADS)
Soodchomshom, Bumned; Niyomsoot, Kittipong; Pattrawutthiwong, Eakkarat
2018-03-01
The magnetoresistance and spin-valley transport properties in a silicene-based NM/FB/SC junction are investigated, where NM, FB and SC are normal, ferromagnetic and s-wave superconducting silicene, respectively. In the FB region, perpendicular electric and staggered exchange fields are applied. The quasiparticles may be described by Dirac Bogoliubov-de Gennes equation due to Cooper pairs formed by spin-valley massive fermions. The spin-valley conductances are calculated based on the modified Blonder-Tinkham-Klapwijk formalism. We find the spin-valley dependent Andreev resonant peaks in the junction shifted by applying exchange field. Perfect conductance switch generated by interplay of intrinsic spin orbit interaction and superconducting gap has been predicted. Spin and valley polarizations are almost linearly dependent on biased voltage near zero bias and then turn into perfect switch at biased voltage approaching the superconducting gap. The perfect switching of large magnetoresistance has been also predicted at biased energy near the superconducting gap. These switching effects may be due to the presence of spin-valley Andreev resonant peak near the superconducting gap. Our work reveals potential of silicene as applications of electronic switching devices and linear control of spin and valley polarizations.
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ERIC Educational Resources Information Center
Minnesota Univ., Minneapolis. Project Social Studies Curriculum Center.
Readings designed to accompany Unit IV, (ED 069 562) which is intended for fifth grade students, describe the Birmingham region from 1812 to 1872. Nine themes in the study illustrate settlement in the valley, early growth in Birmingham, and the changing use of the area in terms of different perceptions of natural resources. Technical advancement…
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Mountaintop removal and valley fill coal mining has altered the physicochemical landscape of the Central Appalachian region in the U.S. Increased specific conductance and levels of component ions downstream from valley fill sites are toxic to aquatic life and can negatively impa...
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NASA Astrophysics Data System (ADS)
Freedman, Jeffrey M.; Fitzjarrald, David R.
2017-02-01
We examine cases of a regional elevated mixed layer (EML) observed during the Hudson Valley Ambient Meteorology Study (HVAMS) conducted in New York State, USA in 2003. Previously observed EMLs referred to topographic domains on scales of 105 -106 km2 . Here, we present observational evidence of the mechanisms responsible for the development and maintenance of regional EMLs overlying a valley-based convective boundary layer (CBL) on much smaller spatial scales (<5000 km2) . Using observations from aircraft-based, balloon-based, and surface-based platforms deployed during the HVAMS, we show that cross-valley horizontal advection, along-valley channelling, and fog-induced cold-air pooling are responsible for the formation and maintenance of the EML and valley-CBL coupling over New York State's Hudson Valley. The upper layer stability of the overlying EML constrains growth of the valley CBL, and this has important implications for air dispersion, aviation interests, and fog forecasting.
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Belcher, Wayne R.; Faunt, Claudia C.; D'Agnese, Frank A.
2002-01-01
The U.S. Geological Survey, in cooperation with the Department of Energy and other Federal, State, and local agencies, is evaluating the hydrogeologic characteristics of the Death Valley regional ground-water flow system. The ground-water flow system covers an area of about 100,000 square kilometers from latitude 35? to 38?15' North to longitude 115? to 118? West, with the flow system proper comprising about 45,000 square kilometers. The Death Valley regional ground-water flow system is one of the larger flow systems within the Southwestern United States and includes in its boundaries the Nevada Test Site, Yucca Mountain, and much of Death Valley. Part of this study includes the construction of a three-dimensional hydrogeologic framework model to serve as the foundation for the development of a steady-state regional ground-water flow model. The digital framework model provides a computer-based description of the geometry and composition of the hydrogeologic units that control regional flow. The framework model of the region was constructed by merging two previous framework models constructed for the Yucca Mountain Project and the Environmental Restoration Program Underground Test Area studies at the Nevada Test Site. The hydrologic characteristics of the region result from a currently arid climate and complex geology. Interbasinal regional ground-water flow occurs through a thick carbonate-rock sequence of Paleozoic age, a locally thick volcanic-rock sequence of Tertiary age, and basin-fill alluvium of Tertiary and Quaternary age. Throughout the system, deep and shallow ground-water flow may be controlled by extensive and pervasive regional and local faults and fractures. The framework model was constructed using data from several sources to define the geometry of the regional hydrogeologic units. These data sources include (1) a 1:250,000-scale hydrogeologic-map compilation of the region; (2) regional-scale geologic cross sections; (3) borehole information, and (4
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Valley Fever (Coccidioidomycosis) Statistics
... Valley fever may be under-recognized. 2 , 3 Public health surveillance for Valley fever Valley fever is reportable ... MMWR) . Check with your local, state, or territorial public health department for more information about disease reporting requirements ...
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Garner, Bradley D.; Pool, D.R.; Tillman, Fred D.; Forbes, Brandon T.
2013-01-01
Water budgets were developed for the Verde Valley of central Arizona in order to evaluate the degree to which human stresses have affected the hydrologic system and might affect it in the future. The Verde Valley is a portion of central Arizona wherein concerns have been raised about water availability, particularly perennial base flow of the Verde River. The Northern Arizona Regional Groundwater Flow Model (NARGFM) was used to generate the water budgets and was run in several configurations for the 1910–2005 and 2005–2110 time periods. The resultant water budgets were subtracted from one another in order to quantify the relative changes that were attributable solely to human stresses; human stresses included groundwater withdrawals and incidental and artificial recharge but did not include, for example, human effects on the global climate. Three hypothetical and varied conditions of human stresses were developed and applied to the model for the 2005–2110 period. On the basis of this analysis, human stresses during 1910–2005 were found to have already affected the hydrologic system of the Verde Valley, and human stresses will continue to affect the hydrologic system during 2005–2110. Riparian evapotranspiration decreased and underflow into the Verde Valley increased because of human stresses, and net groundwater discharge to the Verde River in the Verde Valley decreased for the 1910–2005 model runs. The model also showed that base flow at the upstream end of the study area, as of 2005, was about 4,900 acre-feet per year less than it would have been in the absence of human stresses. At the downstream end of the Verde Valley, base flow had been reduced by about 10,000 acre-feet per year by the year 2005 because of human stresses. For the 2005–2110 period, the model showed that base flow at the downstream end of the Verde Valley may decrease by an additional 5,400 to 8,600 acre-feet per year because of past, ongoing, and hypothetical future human
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Langenheim, V.E.; Wright, T.L.; Okaya, D.A.; Yeats, R.S.; Fuis, G.S.; Thygesen, K.; Thybo, H.
2011-01-01
Industry seismic reflection data, oil test well data, interpretation of gravity and magnetic data, and seismic refraction deep-crustal profiles provide new perspectives on the subsurface geology of San Fernando Valley, home of two of the most recent damaging earthquakes in southern California. Seismic reflection data provide depths to Miocene–Quaternary horizons; beneath the base of the Late Miocene Modelo Formation are largely nonreflective rocks of the Middle Miocene Topanga and older formations. Gravity and seismic reflection data reveal the North Leadwell fault zone, a set of down-to-the-north faults that does not offset the top of the Modelo Formation; the zone strikes northwest across the valley, and may be part of the Oak Ridge fault system to the west. In the southeast part of the valley, the fault zone bounds a concealed basement high that influenced deposition of the Late Miocene Tarzana fan and may have localized damage from the 1994 Northridge earthquake. Gravity and seismic refraction data indicate that the basin underlying San Fernando Valley is asymmetric, the north part of the basin (Sylmar subbasin) reaching depths of 5–8 km. Magnetic data suggest a major boundary at or near the Verdugo fault, which likely started as a Miocene transtensional fault, and show a change in the dip sense of the fault along strike. The northwest projection of the Verdugo fault separates the Sylmar subbasin from the main San Fernando Valley and coincides with the abrupt change in structural style from the Santa Susana fault to the Sierra Madre fault. The Simi Hills bound the basin on the west and, as defined by gravity data, the boundary is linear and strikes ~N45°E. That northeast-trending gravity gradient follows both the part of the 1971 San Fernando aftershock distribution called the Chatsworth trend and the aftershock trends of the 1994 Northridge earthquake. These data suggest that the 1971 San Fernando and 1994 Northridge earthquakes reactivated portions of
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Temperature and Precipitation trends in Kashmir valley, North Western Himalayas
NASA Astrophysics Data System (ADS)
Shafiq, Mifta Ul; Rasool, Rehana; Ahmed, Pervez; Dimri, A. P.
2018-01-01
Climate change has emerged as an important issue ever to confront mankind. This concern emerges from the fact that our day-to-day activities are leading to impacts on the Earth's atmosphere that has the potential to significantly alter the planet's shield and radiation balance. Developing countries particularly whose income is particularly derived from agricultural activities are at the forefront of bearing repercussions due to changing climate. The present study is an effort to analyze the changing trends of precipitation and temperature variables in Kashmir valley along different elevation zones in the north western part of India. As the Kashmir valley has a rich repository of glaciers with its annual share of precipitation, slight change in the temperature and precipitation regime has far reaching environmental and economic consequences. The results from Indian Meteorological Department (IMD) data of the period 1980-2014 reveals that the annual mean temperature of Kashmir valley has increased significantly. Accelerated warming has been observed during 1980-2014, with intense warming in the recent years (2001-2014). During the period 1980-2014, steeper increase, in annual mean maximum temperature than annual mean minimum temperature, has been observed. In addition, mean maximum temperature in plain regions has shown higher rate of increase when compared with mountainous areas. In case of mean minimum temperature, mountainous regions have shown higher rate of increase. Analysis of precipitation data for the same period shows a decreasing trend with mountainous regions having the highest rate of decrease which can be quite hazardous for the fragile mountain environment of the Kashmir valley housing a large number of glaciers.
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Valley polarization in bismuth
NASA Astrophysics Data System (ADS)
Fauque, Benoit
2013-03-01
The electronic structure of certain crystal lattices can contain multiple degenerate valleys for their charge carriers to occupy. The principal challenge in the development of valleytronics is to lift the valley degeneracy of charge carriers in a controlled way. In bulk semi-metallic bismuth, the Fermi surface includes three cigar-shaped electron valleys lying almost perpendicular to the high symmetry axis known as the trigonal axis. The in-plane mass anisotropy of each valley exceeds 200 as a consequence of Dirac dispersion, which drastically reduces the effective mass along two out of the three orientations. According to our recent study of angle-dependent magnetoresistance in bismuth, a flow of Dirac electrons along the trigonal axis is extremely sensitive to the orientation of in-plane magnetic field. Thus, a rotatable magnetic field can be used as a valley valve to tune the contribution of each valley to the total conductivity. As a consequence of a unique combination of high mobility and extreme mass anisotropy in bismuth, the effect is visible even at room temperature in a magnetic field of 1 T. Thus, a modest magnetic field can be used as a valley valve in bismuth. The results of our recent investigation of angle-dependent magnetoresistance in other semi-metals and doped semiconductors suggest that a rotating magnetic field can behave as a valley valve in a multi-valley system with sizeable mass anisotropy.
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NASA Astrophysics Data System (ADS)
Xiang, T.; Vivoni, E. R.; Gochis, D. J.; Mascaro, G.
2015-12-01
Heterogeneous land surface conditions are essential components of land-atmosphere interactions in regions of complex terrain and have the potential to affect convective precipitation formation. Yet, due to their high complexity, hydrologic processes over mountainous regions are not well understood, and are usually parameterized in simple ways within coupled land-atmosphere modeling frameworks. With the improving model physics and spatial resolution of numerical weather prediction models, there is an urgent need to understand how land surface processes affect local and regional meteorological processes. In the North American Monsoon (NAM) region, the summer rainy season is accompanied by a dramatic greening of mountain ecosystems that adds spatiotemporal variability in vegetation which is anticipated to impact the conditions leading to convection, mountain-valley circulations and mesoscale organization. In this study, we present results from a detailed analysis of a high-resolution (1 km) land surface model, Noah-MP, in a large, mountainous watershed of the NAM region - the Rio Sonora (21,264 km2) in Mexico. In addition to capturing the spatial variations in terrain and soil distributions, recently-developed features in Noah-MP allow the model to read time-varying vegetation parameters derived from remotely-sensed vegetation indices; however, this new implementation has not been fully evaluated. Therefore, we assess the simulated spatiotemporal fields of soil moisture, surface temperature and surface energy fluxes through comparisons to remote sensing products and results from coarser land surface models obtained from the North American Land Data Assimilation System. We focus attention on the impact of vegetation changes along different elevation bands on the diurnal cycle of surface energy fluxes to provide a baseline for future analyses of mountain-valley circulations using a coupled land-atmosphere modeling system. Our study also compares limited streamflow
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Fleskes, Joseph P.; Fowler, Ada C.; Casazza, Michael L.; Eadie, John M.
2010-01-01
Female Northern Pintails (Anas acuta) were sampled in California's three main Central Valley wintering regions (Sacramento Valley, Suisun Marsh, San Joaquin Valley) during September–October before most regional movements occur and microsatellite and mitochondrial DNA were analyzed to examine population structure and relatedness. Despite reportedly high rates of early-fall pairing and regional fidelity, both sets of markers indicated that there was little overall genetic structuring by region. Pintails from Suisun Marsh did exhibit higher relatedness among individuals and capture groups than in the Sacramento or San Joaquin Valleys, likely reflecting a sample comprised of a greater proportion of local breeders. The lack of genetic structuring among regions indicates that a high degree of movement and interchange occurs among pintails wintering in the Central Valley. Thus, although maintaining the existing distribution of pintails among Central Valley regions is important for other reasons, it does not appear to be critical to retain current patterns of population genetic variation. Because of potential lack of independence among highly related study individuals, researchers should consider regional differences in relatedness when designing sampling schemes and interpreting research findings.
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The Oasis impact structure, Libya: geological characteristics from ALOS PALSAR-2 data interpretation
NASA Astrophysics Data System (ADS)
van Gasselt, Stephan; Kim, Jung Rack; Choi, Yun-Soo; Kim, Jaemyeong
2017-02-01
Optical and infrared remote sensing may provide first-order clues for the identification of potential impact structures on the Earth. Despite the free availability of at least optical image data at highest resolution, research has shown that remote sensing analysis always remains inconclusive and extensive groundwork is needed for the confirmation of the impact origin of such structures. Commonly, optical image data and digital terrain models have been employed mainly for such remote sensing studies of impact structures. With the advent of imaging radar data, a few excursions have been made to also employ radar datasets. Despite its long use, capabilities of imaging radar for studying surface and subsurface structures have not been exploited quantitatively when applied for the identification and description of such features due to the inherent complexity of backscatter processes. In this work, we make use of higher-level derived radar datasets in order to gain clearer qualitative insights that help to describe and identify potential impact structures. We make use of high-resolution data products from the ALOS PALSAR-1 and ALOS PALSAR-2 L-band sensors to describe the heavily eroded Oasis impact structure located in the Libyan Desert. While amplitude radar data with single polarization have usually been utilized to accompany the suite of remote sensing datasets when interpreting impact structures in the past, we conclude that the integration of amplitude data with HH/HV/HH-HV polarization modes in standard and, in particular, in Ultra-Fine mode, as well as entropy-alpha decomposition data, significantly helps to identify and discriminate surface units based on their consolidation. Based on the overarching structural pattern, we determined the diameter of the eroded Oasis structure at 15.6 ± 0.5 km.
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Recent landscape change in California's Central Valley
NASA Astrophysics Data System (ADS)
Soulard, C. E.; Wilson, T. S.
2012-12-01
Long term monitoring of land use and land cover in California's intensively farmed Central Valley reveals several key physical and socioeconomic factors driving landscape change. As part of the USGS Land Cover Trends Project, we analyzed modern land-use/land-cover change for the California Central Valley ecoregion between 2000 and 2010, monitoring annual change between 2005 and 2010, while creating two new change intervals (2000-2005 and 2005-2010) to update the existing 27-year, interval-based analysis. Between 2000 and 2010, agricultural lands fluctuated due to changes in water allocations and emerging drought conditions, or were lost permanently to development (240 square km). Land-use pressure from agriculture and development also led to a decline in grasslands and shrublands across the region (280 square km). Overall, 400 square km of new developed lands were added in the first decade of the 21st century. From 2007 to 2010, development only expanded by 50 square km, coinciding with defaults in the banking system, the onset of historic foreclosure crisis in California and the global economic downturn. Our annual LULC change estimates capture landscape-level change in response to regional policy changes, climate, and fluctuations (e.g., growth or decline) in the national and global economy. The resulting change data provide insights into the drivers of landscape change in the California Central Valley and the combination of two consistent mapping efforts represents the first continuous, 37-year endeavor of its kind.
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Remote monitoring and Tennessee Valley Authority programs
NASA Technical Reports Server (NTRS)
Stevens, A. R.; Voss, A. W.
1977-01-01
The Tennessee Valley Authority was created in 1933 as a resource development agency and was charged with the basic mission of improving the economy of a depressed region through power production, flood control, and navigation. Those programs which availed themselves of remotely monitored data, either directly or indirectly supporting this mission, were examined.
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Geophysical Data from Spring Valley to Delamar Valley, East-Central Nevada
Mankinen, Edward A.; Roberts, Carter W.; McKee, Edwin H.; Chuchel, Bruce A.; Morin, Robert L.
2007-01-01
Cenozoic basins in eastern Nevada and western Utah constitute major ground-water recharge areas in the eastern part of the Great Basin and these were investigated to characterize the geologic framework of the region. Prior to these investigations, regional gravity coverage was variable over the region, adequate in some areas and very sparse in others. Cooperative studies described herein have established 1,447 new gravity stations in the region, providing a detailed description of density variations in the middle to upper crust. All previously available gravity data for the study area were evaluated to determine their reliability, prior to combining with our recent results and calculating an up-to-date isostatic residual gravity map of the area. A gravity inversion method was used to calculate depths to pre-Cenozoic basement rock and estimates of maximum alluvial/volcanic fill in the major valleys of the study area. The enhanced gravity coverage and the incorporation of lithologic information from several deep oil and gas wells yields a much improved view of subsurface shapes of these basins and provides insights useful for the development of hydrogeologic models for the region.
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The Cenozoic evolution of the San Joaquin Valley, California
Bartow, J. Alan
1991-01-01
The San Joaquin Valley, which is the southern part of the 700-km-long Great Valley of California, is an asymmetric structural trough that is filled with a prism of upper Mesozoic and Cenozoic sediments up to 9 km thick; these sediments rest on crystalline basement rocks of the southwestward-tilted Sierran block. The San Joaquin sedimentary basin is separated from the Sacramento basin to the north by the buried Stockton arch and associated Stockton fault. The buried Bakersfield arch near the south end of the valley separates the small Maricopa-Tejon subbasin at the south end of the San Joaquin basin from the remainder of the basin. Cenozoic strata in the San Joaquin basin thicken southeastward from about 800 m in the north to over 9,000 m in the south. The San Joaquin Valley can be subdivided into five regions on the basis of differing structural style. They are the northern Sierran block, the southern Sierran block, the northern Diablo homocline, the westside fold belt, and the combined Maricopa-Tejon subbasin and southmargin deformed belt. Considerable facies variation existed within the sedimentary basin, particularly in the Neogene when a thick section of marine sediment accumulated in the southern part of the basin, while a relatively thin and entirely nonmarine section was deposited in the northern part. The northern Sierran block, the stable east limb of the valley syncline between the Stockton fault and the San Joaquin River, is the least deformed region of the valley. Deformation consists mostly of a southwest tilt and only minor late Cenozoic normal faulting. The southern Sierran block, the stable east limb of the valley syncline between the San Joaquin River and the Bakersfield arch, is similar in style to the northern part of the block, but it has a higher degree of deformation. Miocene or older normal faults trend mostly north to northwest and have a net down-to-the-west displacement with individual offsets of as much as 600 m. The northern Diablo
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NASA Astrophysics Data System (ADS)
Rigsby, C. A.; Farabaugh, R. L.; Baker, P. A.
2002-12-01
Lacustrine sediments have become important archives of paleoclimatic history in the tropical Andes of South America. The history of lake level of Lake Titicaca (LT) has played a central role in these reconstructions. Here we report on our ongoing studies of the late Quaternary sedimentary and geomorphic histories of two of the major tributaries to LT (the Rios Ramis and Ilave) and on our earlier studies of LT's only outlet (the Rio Desaguadero). The strata and fluvial terraces in these valleys record large-scale aggradation and downcutting events that are apparently correlative with both climate changes in the LT basin and local complex response mechanisms (changes in sediment source, topographic variability, etc.). Both the Ramis and Ilave valleys have 5 terrace tracts, ranging from less than 1 m to approximately 53 m above the river level and occurring as both paired and unpaired tracts and as cut-fill, fill-, and strath terraces. The Rio Desaguadero valley has 4, locally paired, cut-fill and fill terrace tracts that range in height from approximately 2 m to 40 m above river level. In all three valleys, the terraces are underlain by meandering- and braided-river sands and gravels and by lacustrine muds. Radiocarbon dates from the Ilave and Desaguadero valleys suggest that strata in these valleys aggraded during periods of high or rising levels of LT, high or increasing sedimentation rates in the Rio Ilave delta, high (but variable) regional precipitation, and lacustrine sedimentation in the upstream-most reaches of the Rio Desaguadero valley. These same strata were downcut during periods of low or falling levels of LT, low or rapidly decreasing sedimentation rates in the Rio Ilave delta, and lower regional precipitation and runoff. In all three valleys, aggradational periods are punctuated by equilibrium periods of soil formation, downcutting events are episodic, and the most recent events are aggradation and subsequent downcutting of a low, young fill
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Sánchez-Murillo, Ricardo; Esquivel-Hernández, Germain; Sáenz-Rosales, Oscar; Piedra-Marín, Gilberto; Fonseca-Sánchez, Alicia; Madrigal-Solís, Helga; Ulloa-Chaverri, Franz; Rojas-Jiménez, Luis D; Vargas-Víquez, José A
2017-03-01
The linkage between precipitation and recharge is still poorly understood in the Central America region. This study focuses on stable isotopic composition in precipitation and groundwater in the northern mountainous region of the Central Valley of Costa Rica. During the dry season, rainfall samples corresponded to enriched events with high deuterium excess. By mid-May, the Intertropical Convergence Zone poses over Costa Rica resulting in a depletion of 18 O/ 16 O and 2 H/H ratios. A parsimonious four-variable regression model (r 2 = 0.52) was able to predict daily δ 18 O in precipitation. Air mass back trajectories indicated a combination of Caribbean Sea and Pacific Ocean sources, which is clearly depicted in groundwater isoscape. Aquifers relying on Pacific-originated recharge exhibited a more depleted pattern, whereas recharge areas relying on Caribbean parental moisture showed an enrichment trend. These results can be used to enhance modelling efforts in Central America where scarcity of long-term data limits water resources management plans.
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Birds of the St. Croix River valley: Minnesota and Wisconsin
Faanes, Craig A.
1981-01-01
The St. Croix River Valley encompasses nearly 11,550 km2 in east-central Minnesota and northwestern Wisconsin. A wide range of habitats are available for birds including upland oak, lowland deciduous, maple-basswood, lowland and upland coniferous forests, natural basin wetlands, and grasslands. Situated in the north-central region of the United States, the valley is a biological 'crossroads' for many species. Because of the mixed affinities of plant communities, the valley includes the northern and southern range limits for a number of species. Also, because the valley lies near the forest-prairie transition zone, many typical western breeding species (e.g. pintail, western meadowlark, yellow-headed blackbird) breed in proximity to typical eastern species such as tufted titmouse, eastern meadowlark, and cardinal. From 1966 to 1980, I conducted extensive surveys of avian distribution and abundance in the St. Croix River Valley. I have supplemented the results of these surveys with published and unpublished observations contributed by many ornithologists. These additional data include compilations from Christmas Bird Counts sponsored by the National Audubon Society and from the Breeding Bird Survey coordinated by the U.S. Fish and Wildlife Service. Three hundred fourteen species have been recorded in the study area; data are presented on the migration period, nesting season distribution, winter distribution, relative abundance, and habitat use of each species. Recognizing the uniqueness of the area, and its importance not only to wildlife but also to man, the U.S. Congress designated the St. Croix a National Scenic Riverway. This action provided a considerable degree of protection to lands along and directly adjacent to the river. Unfortunately, no similar legal measure exists to protect lands away from the river. With the exception of the northern quarter of the St. Croix River Valley, agricultural interests have made significant inroads into the habitat base. The
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Fusar-Poli, P; Palombini, E; Davies, C; Oliver, D; Bonoldi, I; Ramella-Cravaro, V; McGuire, P
2018-02-01
The reason for declining risk to psychosis across individuals assessed and meeting Ultra High Risk (UHR) criteria is still unclear. No studies have investigated the potential substantial role of the underlying risk enrichment across all the individuals undergoing an UHR assessment. Cohort study including all non-psychotic subjects who were assessed on suspicion of psychosis risk by the OASIS UHR service in the period 2001 to 2015. Posttest (after UHR assessment) and pretest risk (before UHR assessment) of psychosis were stratified and compared across three time periods (2001-2005, 2006-2010, 2011-2015) with Cox analysis and modulating factors were investigated. The posttest risk of psychosis at the OASIS service has increased from the initial pilot years of the service (2001-2005) and then stabilised and not declined over the following decade (2006-2010 and 2011-2015). This was paralleled by a similar course of pretest risk for psychosis. Stability of pretest risk for psychosis over the past decade was associated with a lack of change in ethnicity and to counterweighting changes in the type of referral sources over different time periods. The time course of transition risk to psychosis in UHR services is strictly associated with the time course of pretest risk enrichment. If the latter remains stable over time, as for the OASIS service, no declining transition risk is observed over the most recent years. Pretest risk enrichment is determined by recruitment and sampling strategies. This study confirms the need to control these factors in the UHR field. Copyright © 2017 Elsevier B.V. All rights reserved.
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Unexpected Rift Valley Fever Outbreak, Northern Mauritania
El Mamy, Ahmed B. Ould; Baba, Mohamed Ould; Barry, Yahya; Isselmou, Katia; Dia, Mamadou L.; Hampate, Ba; Diallo, Mamadou Y.; El Kory, Mohamed Ould Brahim; Diop, Mariam; Lo, Modou Moustapha; Thiongane, Yaya; Bengoumi, Mohammed; Puech, Lilian; Plee, Ludovic; Claes, Filip; Doumbia, Baba
2011-01-01
During September–October 2010, an unprecedented outbreak of Rift Valley fever was reported in the northern Sahelian region of Mauritania after exceptionally heavy rainfall. Camels probably played a central role in the local amplification of the virus. We describe the main clinical signs (hemorrhagic fever, icterus, and nervous symptoms) observed during the outbreak. PMID:22000364
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Optical manipulation of valley pseudospin
Ye, Ziliang; Sun, Dezheng; Heinz, Tony F.
2016-09-19
The coherent manipulation of spin and pseudospin underlies existing and emerging quantum technologies, including quantum communication and quantum computation. Valley polarization, associated with the occupancy of degenerate, but quantum mechanically distinct valleys in momentum space, closely resembles spin polarization and has been proposed as a pseudospin carrier for the future quantum electronics. Valley exciton polarization has been created in the transition metal dichalcogenide monolayers using excitation by circularly polarized light and has been detected both optically and electrically. In addition, the existence of coherence in the valley pseudospin has been identified experimentally. The manipulation of such valley coherence has, however,more » remained out of reach. In this paper, we demonstrate all-optical control of the valley coherence by means of the pseudomagnetic field associated with the optical Stark effect. Using below-bandgap circularly polarized light, we rotate the valley exciton pseudospin in monolayer WSe 2 on the femtosecond timescale. Both the direction and speed of the rotation can be manipulated optically by tuning the dynamic phase of excitons in opposite valleys. Finally, this study unveils the possibility of generation, manipulation, and detection of the valley pseudospin by coupling to photons.« less
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Chemistry and Mineralogy of Antarctica Dry Valley Soils: Implications for Mars
NASA Technical Reports Server (NTRS)
Quinn, J. E.; Golden, D. C.; Graff, T. G.; Ming, D. W.; Morris, R. V.; Douglas, S.; Kounaves, S. P.; McKay, C. P.; Tamppari, L, K.; Smith, P. H.;
2011-01-01
The Antarctic Dry Valleys (ADV) comprise the largest ice-free region of Antarctica. Precipitation almost always occurs as snow, relative humidity is frequently low, and mean annual temperatures are about -20 C. The ADV soils have previously been categorized into three soil moisture regimes: subxerous, xerous and ultraxerous, based on elevation and climate influences. The subxerous regime is predominately a coastal zone soil, and has the highest average temperature and precipitation, while the ultraxerous regime occurs at high elevation (>1000 m) and have very low temperature and precipitation. The amounts and types of salts present in the soils vary between regions. The nature, origin and significance of salts in the ADV have been previously investigated. Substantial work has focused on soil formation in the ADVs, however, little work has focused on the mineralogy of secondary alteration phases. The dominant weathering process in the ADV region is physical weathering, however, chemical weathering has been well documented. The objective of this study was to characterize the chemistry and mineralogy, including the alteration mineralogy, of soils from two sites, a subxerous soil in Taylor Valley, and an ultraxerous soil in University Valley. The style of aqueous alteration in the ADVs may have implications for pedogenic processes on Mars.
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Shaded relief aeromagnetic map of the Santa Clara Valley and vicinity, California
Roberts, Carter W.; Jachens, Robert C.
2003-01-01
This aeromagnetic map covers the southern portion of San Francisco Bay, the Santa Clara Valley and surrounding mountains, part of which has been modelled in threedimensions (Jachens and other, 2001). The magnetic anomaly map has been compiled from existing digital data. Data was obtained from six aeromagnetic surveys that were flown at different times, spacings and elevations. The International Geomagnetic Reference Field (IGRF) for the date of each survey had been removed in the initial processing. The resulting residual magnetic anomalies were analytically continued onto a common surface 305 m (1000 ft) above terrain. Portions of each survey were substantially above the specified flight height listed in the table. The surveys were then merged together using a commercial software package called Oasis Montage. The gray lines on the map indicate the extent of each survey. The program used these regions of overlap to determine the best fit between surveys. Black dots show probable edges of magnetic bodies defined by the maximum horizontal gradient determined using a computer program by Blakely (1995). Crystalline rocks generally contain sufficient magnetic minerals to cause variations in the Earth’s magnetic field that can be mapped by aeromagnetic surveys. Sedimentary rocks are generally weakly magnetized and consequently have a small effect on the magnetic field: thus a magnetic anomaly map can be used to “see through” the sedimentary rock cover and can convey information on lithologic contrasts and structural trends related to the underlying crystalline basement (see Nettleton,1971; Blakely, 1995). Faults often cut magnetic bodies and offset magnetic anomalies can thus be used to help determine fault motion. Serpentinite, which is highly magnetic, is often found along faults. On this map areas of low magnetic anomalies are shown in blues and green while highs are shown in reds and magentas. Faults are from Brabb and others, 1998a,1998b, Graymer and others
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NASA Astrophysics Data System (ADS)
Giardino, Marco; Bacenetti, Marco; Perotti, Luigi; Giordano, Enrico; Ghiraldi, Luca; Palomba, Mauro
2013-04-01
Mountain regions have a range of geological and geomorphological features that make them very attractive for tourism activities. As a consequence, increased human "pressure" causes impacts on geoheritage sites and higher geomorphological risks. These effects are magnified by active geomorphic processes characterizing mountains areas, highly sensitive to climate change. In term of "human sensitivity", several sociological surveys have shown that "perceived risk", not "real risk", influences people's behavior towards natural hazards. The same approach can be applied to geodiversity and geoheritage. Based on these assumptions, we considered the possible strategic roles played by diffusion of scientific research and application of new technologies: 1) to enhance awareness, either of geodiversity or environmental dynamics and 2) to improve knowledge, both on geoheritage management and natural risk reduction. Within the activities of the "ProGEO-Piemonte Project" (Progetti d'Ateneo 2011, cofunded by Universita? degli Studi di Torino and Compagnia di San Paolo Bank Foundation), we performed a systematic review of geodiversity and natural hazards information in the Piemonte Region (NW-Italy). Then we focused our attention on the Susa Valley, an area of the Western Alps where the geoheritage is affected by very active morphodynamics, as well as by a growing tourism, after the 2006 winter Olympics. The Susa Valley became one of the 9 strategic geothematic areas have been selected to represent the geodiversity of the Piemonte region, each characterized by high potential for enhancement of public understanding of science, and recreation activities supported by local communities. Then we contributed to the awareness-raising communication strategy of the "RiskNat project" (Interreg Alcotra 2007-2013, Action A.4.3) by synthesizing geoscience knowledge on the Susa Valley and information on slope instabilities and models/prevention measures/warning systems. Visual representations
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De Cordier, B
1996-01-01
This work seeks to demonstrate that the combination of ecological degradation, demographic pressure, and ethnic heterogeneity in Central Asia constitute a serious threat to the future stability of the region. The predominantly rural Ferghana Valley and Northern Kazakhstan suffer from shortages of water and land and from unemployment that leads to extensive out-migration to cities suffering from decline in their Soviet-era industries. The problem in the Ferghana Valley began with Tsarist conquest of the valley in 1876 and the subsequent imposition of cotton cultivation, which was greatly expanded by the Soviet Union. The Ferghana Valley, despite being a natural unit, was divided between Uzbekistan, Tajikistan, and Kyrgyzstan in the 1920s and 1930s, and remains divided between the independent states. The current population of 11 million is ethnically diverse, with Uzbeks in the majority and increasing most rapidly. Immigration from the Caucasus since 1950 added to the tension. Future peace will depend on such factors as whether the neo-Communist political regime chooses to incite ethnic hostilities, the manner in which land is redistributed, and the outcome of struggles for control of the flourishing narcotics trade. The northern Kazakhstan region was designated a pioneer wheat-growing region by Soviet planners in 1954. Russian and Ukrainian migrants established between 1954 and 1956 are today the predominant population sector, but feel their privileged position threatened by nationalist policies making Kazakh the official language and giving preference in employment to Kazakhs. Resettlement of Kazakhs from Mongolia, China, and Afghanistan in the region and the high Kazakh birth rate increase tensions. Grain production initially grew rapidly, but the mediocre soil and erosion-inducing constant dry winds have caused production to stagnate or decline. Regional disputes within Kazakhstan complicate the situation. Northern Kazakhstan, with its industrial development, is
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The Breakup of Temperature Inversions In Steep Valleys
NASA Astrophysics Data System (ADS)
Colette, A.; Street, R.
The purpose of this research is to model and provide a better understanding of tem- perature inversions breakup in steep valleys. The Advanced Regional Prediction Sys- tem (ARPS), a three-dimensional, compressible, and non-hydrostatic modeling tool developed by the Center for Analysis and Prediction of Storms at the University of Oklahoma was used. Many field studies indicate that the evolution of the convective and inversion layers are strongly dependant on the surrounding topography. In relatively open valleys, the convective boundary layer usually grows from the bottom of the valley while in steeper cases, the upslope morning winds affects the dynamic of the mixing layer resulting in the destruction of the inversion from its bottom and its top (see Whiteman 1980). ARPS allows one to perform accurate simulation of such situations. First, written in terrain following coordinates, it handles steep topographies; then its extensive radi- ation and surface flux packages provide a good treatment of land related processes. Moreover, ARPS accounts for the incidence angle of sunrays, differencing the ex- posed and non-exposed mountain slopes. However, it neglects the topographic shade which can delay the sunrise of a hour or more in steep valleys. A new subroutine described by Colette etal. 2002 is thus used to compute the projected shade on the surrounding topography. Simulations of temperature inversion breakup for various two-dimensional valleys are presented. The time scale of evolution of the mixing layer is in good agreement with field studies and, as expected, the convective boundary layer shows an asymmetry between east and west facing slopes. The different patterns of inversion breakup doc- umented by Whiteman are also reproduced. These simulations of idealized cases give a better understanding of inversion breakup in steep valleys. Our code is now being applied to a real case: the study of a peculiar wind, la Ora del Garda, caused by the interaction between a
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DOT National Transportation Integrated Search
2006-08-02
In 2000, the Treasure Valley area of the State of Idaho received a federal earmark of $390,000 to develop an Advanced Transportation Management System (ATMS) for the Treasure Valley region of Idaho. The Ada County Highway District (ACHD), located in ...
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Community Survey Results for Rappahannock River Valley National Wildlife Refuge: Completion Report
Sexton, Natalie R.; Stewart, Susan C.; Koontz, Lynne
2008-01-01
This report provides a summary of results for the survey of residents of communities adjacent to Rappahannock River Valley NWR conducted from the spring through the summer in 2006. This research was commissioned by the Northeast Region of the U.S. Fish and Wildlife Service in support of the Rappahannock River Valley NWR CCP and conducted by the Policy Analysis and Science Assistance Branch (PASA) of the U.S. Geological Survey/Fort Collins Science Center.
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Measurements of Refractory Black Carbon (rBC) Aerosols in the McMurdo Dry Valleys, Antarctica
NASA Astrophysics Data System (ADS)
Khan, A. L.; McMeeking, G. R.; Lyons, W. B.; Schwarz, J. P.; Welch, K. A.; McKnight, D. M.
2015-12-01
Measurements of light absorbing particles in the boundary layer of the high southern latitudes are scarce. During the 2013-2014 austral summer field season refractory black carbon (rBC) aerosols were quantified by a single particle soot photometer (SP2) in the McMurdo Dry Valleys, Antarctica. The dark rBC particles absorb more radiation thereby increasing atmospheric heating, as well as reducing surface albedo and enhancing hydrologic melt when deposited on highly reflective surfaces such as snow and ice. Quantifying both local and long-range atmospheric transport of rBC to this region of a remote continent mostly covered by ice and snow would be useful in understanding meltwater generation as climate changes. Although the Dry Valleys are the largest ice-free region of Antarctica, they contain many alpine glaciers, some of which are fed from the East Antarctic Ice Sheet (EAIS). Continuous rBC measurements were collected at Lake Hoare Camp in the Taylor Valley for two months, along with shorter periods at more remote locations within the Dry Valleys. Conditions at the Lake Hoare Camp were dominated by up-valley winds from McMurdo Sound, however, winds also brought air down-valley from the EAIS polar plateau. Here we investigated periods dominated by both up and down-valley winds to explore differences in rBC concentrations, size distributions, and scattering properties. The average background rBC mass concentration was 1ng/m3, though concentrations as high as 50 ng/m3 were observed at times, likely due to local sources.
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Chuckwalla Valley multiple-well monitoring site, Chuckwalla Valley, Riverside County
Everett, Rhett
2013-01-01
The U.S. Geological Survey (USGS), in cooperation with the Bureau of Land Management, is evaluating the geohydrology and water availability of the Chuckwalla Valley, California. As part of this evaluation, the USGS installed the Chuckwalla Valley multiple-well monitoring site (CWV1) in the southeastern portion of the Chuckwalla Basin. Data collected at this site provide information about the geology, hydrology, geophysics, and geochemistry of the local aquifer system, thus enhancing the understanding of the geohydrologic framework of the Chuckwalla Valley. This report presents construction information for the CWV1 multiple-well monitoring site and initial geohydrologic data collected from the site.
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Potential for a significant deep basin geothermal system in Tintic Valley, Utah
NASA Astrophysics Data System (ADS)
Hardwick, C.; Kirby, S.
2014-12-01
The combination of regionally high heat flow, deep basins, and permeable reservoir rocks in the eastern Great Basin may yield substantial new geothermal resources. We explore a deep sedimentary basin geothermal prospect beneath Tintic Valley in central Utah using new 2D and 3D models coupled with existing estimates of heat flow, geothermometry, and shallow hydrologic data. Tintic Valley is a sediment-filled basin bounded to the east and west by bedrock mountain ranges where heat-flow values vary from 85 to over 240 mW/m2. Based on modeling of new and existing gravity data, a prominent 30 mGal low indicates basin fill thickness may exceed 2 km. The insulating effect of relatively low thermal conductivity basin fill in Tintic Valley, combined with typical Great Basin heat flow, predict temperatures greater than 150 °C at 3 km depth. The potential reservoir beneath the basin fill is comprised of Paleozoic carbonate and clastic rocks. The hydrology of the Tintic Valley is characterized by a shallow, cool groundwater system that recharges along the upper reaches of the basin and discharges along the valley axis and to a series of wells. The east mountain block is warm and dry, with groundwater levels just above the basin floor and temperatures >50 °C at depth. The west mountain block contains a shallow, cool meteoric groundwater system. Fluid temperatures over 50 °C are sufficient for direct-use applications, such as greenhouses and aquaculture, while temperatures exceeding 140°C are suitable for binary geothermal power plants. The geologic setting and regionally high heat flow in Tintic Valley suggest a geothermal resource capable of supporting direct-use geothermal applications and binary power production could be present.
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Orbital and Rover-based Exploration of Perseverance Valley, Endeavour Crater, Mars
NASA Astrophysics Data System (ADS)
Morgan, A. M.; Arvidson, R. E.; Duran Vinent, O.; Craddock, R. A.; Holo, S.; Gadal, C.; Blois, G.; Palucis, M. C.; Goudge, T. A.; Morgan, A. M.; Day, M.; Sullivan, R. J., Jr.; Umurhan, O. M.; Pähtz, T.; Birch, S.; Morgan, A. M.; Goudge, T. A.; Palucis, M. C.; Arvidson, R. E.; Duran Vinent, O.; Craddock, R. A.; Holo, S.; Blois, G.; Gadal, C.; Morgan, A. M.; Sullivan, R. J., Jr.; Day, M.; Arvidson, R. E.
2017-12-01
Perseverance Valley, based on orbital observations from the Mars Reconnaisance Orbiter HiRISE image data, is a 180 m long, 20 m wide anastomosing shallow channel system superimposed on the Cape Byron rim segment of the 22 km diameter Noachian-age Endeavour Crater on Mars. Several impact craters are superimposed on the valley system, indicating antiquity, although the valley's high degree of preservation indicates that it formed after significant regional-scale fluvial erosion and diffusive smoothing of Endeavour and its rim segments. The valley cuts into the inner, eastern rim on a 10˚ to 15˚ slope, and starts at a local low area on the rim crest. A set of shallow channels, some lined with perimeter rocks, extends from the west to meet the entrance to the valley. The western rim tilts to the west 0.8˚ and thus the channels tilt away from the valley entrance. The Mars Rover Opportunity has explored the western shallow channels leading up to the entrance to the valley. As of this writing Opportunity is located on the southern side of the valley entrance, with the Athena Science Team waiting until after solar conjunction to command the rover to descend into the valley to search for geomorphic and sedimentologic evidence related to valley formation. Wind erosion along radial fractures extending into and down Cape Byron is a possibility. Debris flows are also under consideration, perhaps enabled by melting ice at the rim crest. Dry avalanches are unlikely due to the low slopes. A fluvial origin is a strong contender based on models that show it is possible to have had a western catchment present when the Burns formation hydrated sulfates were being emplaced, followed by self-compaction of these sediments that tilted the western plains away from the rim crest. The key to testing among the various hypotheses for formation of the valley and shallow channels leading into the entrance will be the detailed stereo and multispectral imaging observations Opportunity will make
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Titan's fluvial valleys: Morphology, distribution, and spectral properties
Langhans, M.H.; Jaumann, R.; Stephan, K.; Brown, R.H.; Buratti, B.J.; Clark, R.N.; Baines, K.H.; Nicholson, P.D.; Lorenz, R.D.; Soderblom, L.A.; Soderblom, J.M.; Sotin, Christophe; Barnes, J.W.; Nelson, R.
2012-01-01
Titan's fluvial channels have been investigated based on data obtained by the Synthetic Aperture Radar (SAR) instrument and the Visible and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft. In this paper, a database of fluvial features is created based on radar-SAR data aiming to unveil the distribution and the morphologic and spectral characteristics of valleys on Titan on a global scale. It will also study the spatial relations between fluvial valleys and Titan's geologic units and spectral surface units which have become accessible thanks to Cassini-VIMS data. Several distinct morphologic types of fluvial valleys can be discerned by SAR-images. Dendritic valley networks appear to have much in common with terrestrial dendritic systems owing to a hierarchical and tree-shaped arrangement of the tributaries which is indicative of an origin from precipitation. Dry valleys constitute another class of valleys resembling terrestrial wadis, an indication of episodic and strong flow events. Other valley types, such as putative canyons, cannot be correlated with rainfall based on their morphology alone, since it cannot be ruled out that they may have originated from volcanic/tectonic action or groundwater sapping. Highly developed and complex fluvial networks with channel lengths of up to 1200 km and widths of up to 10 km are concentrated only at a few locations whereas single valleys are scattered over all latitudes. Fluvial valleys are frequently found in mountainous areas. Some terrains, such as equatorial dune fields and undifferentiated plains at mid-latitudes, are almost entirely free of valleys. Spectrally, fluvial terrains are often characterized by a high reflectance in each of Titan's atmospheric windows, as most of them are located on Titan's bright 'continents'. Nevertheless, valleys are spatially associated with a surface unit appearing blue due to its higher reflection at 1.3??m in a VIMS false color RGB composite with R: 1.59/1.27??m, G: 2
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NASA Astrophysics Data System (ADS)
Farr, T. G.; Fairbanks, A.
2017-12-01
Recent rains in California caused a pause, and even a reversal in some areas, of the subsidence that has plagued the Central Valley for decades. The 3 main drivers of surface deformation in the Central Valley are: Subsurface hydro-geology, precipitation and surface water deliveries, and groundwater pumping. While the geology is relatively fixed in time, water inputs and outputs vary greatly both in time and space. And while subsurface geology and water inputs are reasonably well-known, information about groundwater pumping amounts and rates is virtually non-existent in California. We have derived regional maps of surface deformation in the region for the period 2006 - present which allow reconstruction of seasonal and long-term changes. In order to understand the spatial and temporal patterns of subsidence and rebound in the Central Valley, we have been compiling information on the geology and water inputs and have attempted to infer pumping rates using maps of fallowed fields and published pumping information derived from hydrological models. In addition, the spatial and temporal patterns of hydraulic head as measured in wells across the region allow us to infer the spatial and temporal patterns of groundwater pumping and recharge more directly. A better understanding of how different areas (overlying different stratigraphy) of the Central Valley respond to water inputs and outputs will allow a predictive capability, potentially defining sustainable pumping rates related to water inputs. * work performed under contract to NASA and the CA Dept. of Water Resources
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USDA-ARS?s Scientific Manuscript database
The date palm (Phoenix dactylifera) is the only indigenous, wild desert plant definitely domesticated in its native harsh environment, and along with the camel (Camelus dromedarius), was responsible for opening the vast desert territories for human activity and the development of oasis ecosystems, w...
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Valley Fever: Earth Observations for Risk Reduction
NASA Astrophysics Data System (ADS)
Sprigg, W. A.
2012-12-01
Advances in satellite Earth observation systems, numerical weather prediction, and dust storm modeling yield new tools for public health warnings, advisories and epidemiology of illnesses associated with airborne desert dust. Valley Fever, endemic from California through the US/Mexico border region into Central and South America, is triggered by inhalation of soil-dwelling fungal spores. The path from fungal growth to airborne threat depends on environmental conditions observable from satellite. And space-based sensors provide initial conditions for dust storm forecasts and baselines for the epidemiology of Valley Fever and other dust-borne aggravation of respiratory and cardiovascular disease. A new Pan-American Center for the World Meteorological Organization Sand and Dust Storm Warning Advisory and Assessment System creates an opportunity to advance Earth science applications in public health.
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Eoff, Jennifer D.; Dubiel, Russell F.; Pearson, Ofori N.; Whidden, Katherine J.
2015-01-01
The Cotton Valley Group extends in the subsurface from southern Texas to the Florida Panhandle in an arcuate belt that crosses northern Louisiana, the southern part of Arkansas, and southern Mississippi and Alabama. Three of the AUs are quantitatively assessed for undiscovered volumes of hydrocarbons in conventional accumulations. The Cotton Valley Updip Oil AU includes areas between the maximum updip limit of the Cotton Valley Group and a curved belt of regional faults (included in the Peripheral Fault System AU). Hydrocarbon charge to this AU remains uncertain. The Peripheral Fault System Oil and Gas AU includes the Mexia, Talco, State Line, South Arkansas, Pickens, Gilbertown, and other fault segments, which trapped early oil that migrated from source rocks within the Smackover Formation. Hydrocarbons in the Downdip Oil and Gas AU are primarily associated with low-amplitude salt-related features in the East Texas, North Louisiana, and Mississippi salt basins. The Tight Sandstone Gas AU contains gas-charged sandstones previously referred to collectively as “massive.” Their reservoir properties are consistent with the USGS’s definition of continuous reservoirs, and their resources, therefore, are assessed using a separate methodology. Optimal coincidence of low-permeability sandstone, gas-mature source rocks, and complex structures of the regional Sabine feature encouraged development of a general “sweet spot” area in eastern Texas.
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The Northwestern Slope Valleys Region, Mars: A Prime Target for the Future Exploration of Mars
NASA Astrophysics Data System (ADS)
Dohm, J. M.; Ferris, J. C.; Anderson, R. C.; Baker, V. R.; Hare, T. M.; Mahaney, W. C.
2002-12-01
Mars is a water-enriched planet theorized to have had Earth-like conditions during its embryonic stages of evolution (Early into Middle Noachian or > 3.8 GA). The Earth-like conditions include: (1) plate tectonism, (2) an active hydrosphere resulting in higher erosion rates and the presence of layered sedimentary deposits, and (3) a potential biosphere. Due to its smaller size and lower gravity, its thermal energy rapidly declined, sending the planet into a permanent monoplate regime. The Tharsis superplume, Elysium superplume, and structural discontinuities in the lithosphere are sites of long-lived energy releases and hydrothermal activity. Furthermore, as its atmosphere thinned and cooled, and water was lost to hydrodynamic escape, the Earth-like hydrological cycle transitioned into a persisting cold desert climate, approximating the present-day climate of the Dry Valleys in Antarctica. Stratigraphic, hydrogeomorphic, and paleotectonic information indicate an active Mars (e.g., late-stage superplume activity) that experienced punctuated periods of magmatic-driven hydrologic activity long after the Earth-like hydrologic regime had ended. Existing geologic, geomorphic, geophysical, topographic, impact cratering, spectral, and elemental information collectively point to a prime target site for future exploration that has the potential to yield significant geologic, paleoclimatic, paleohydrologic, and exobiologic information. The Northwestern Slope Valleys (NSVs) region archives traits similar to terrestrial field sites where the processes associated with: (1) fluvial, eolian, and hydrothermal activity, (2) modification due to landslides and glaciers, and (3) the formation of diverse rock assemblages (e.g., provenances include Noachian Thaumasia highlands mountain range and Europe-sized sedimentary basin and Noachian-Amazonian basaltic and possibly silica-enriched volcanoes and lava flow fields) are recorded. The region is especially remarkable since it encapsulates
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The Salzach Valley overdeeping: A most precise bedrock model of a major alpine glacial basin
NASA Astrophysics Data System (ADS)
Pomper, Johannes; Salcher, Bernhard; Eichkitz, Christoph
2016-04-01
Overdeepenings are impressive phenomena related to the erosion in the ablation zone of major glaciers. They are common features in glaciated and deglaciated regions worldwide and their sedimentary fillings may act as important archives for regional environmental change and glaciation history. Sedimentary fillings are also important targets of geotechnical exploration and construction including groundwater resource management, shallow geothermal exploitation, tunneling and the foundation of buildings. This is especially true in densely populated areas such as the European Alps and their foreland areas, regions which have been multiply glaciated during the last million years. However, due depths often exceeding some hundreds of meters, the overall knowledge on their geometry, formation and sedimentary content is still poor and commonly tied to some local spots. Here we present a bedrock model of the overall lower Salzach Valley, one of the largest glacial overdeepings in the European Alps. We utilized seismic sections from hydrocarbon exploration surveys and deep drillings together with topographic and modelling data to construct a 3D bedrock model. Through the existence of seismic inline and crossline valley sections, multiple drillings reaching the bedrock surface, log and abundant outcrop data we were, as far to our knowledge, able to create the most accurate digital bedrock topography of an alpine major overdeepening. We furthermore analyzed the sedimentary content of the valley as recorded by driller's lithologic logs. Our results suggest that the valley is far from being a regular U-shaped trough with constant depth, rather highlighting highs and lows of different magnitude and underground valley widths of variable extent. Data also indicates that the largest overdeepening of bedrock, reaching around 450 m below the alluvial fill, is not situated after a major glacial confluence following a prominent bedrock gorge but shifted several km down the valley. The
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Valley- and spin-filter in monolayer MoS2
NASA Astrophysics Data System (ADS)
Majidi, Leyla; Zare, Moslem; Asgari, Reza
2014-12-01
We propose a valley- and spin-filter based on a normal/ferromagnetic/normal molybdenum disulfide (MoS2) junction where the polarizations of the valley and the spin can be inverted by reversing the direction of the exchange field in the ferromagnetic region. By using a modified Dirac Hamiltonian and the scattering formalism, we find that the polarizations can be tuned by applying a gate voltage and changing the exchange field in the structure. We further demonstrate that the presence of a topological term (β) in the Hamiltonian results in an enhancement or a reduction of the charge conductance depending on the value of the exchange field.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Sweetkind, D.S.; White, D.K.
Late Proterozoic through Lower Cambrian rocks in the southern Great Basin form a westward-thickening wedge of predominantly clastic deposits that record deposition on the early western shelf edge of western North America (Stewart and Poole, 1974; Poole and others, 1992). Regional analyses of geologic controls on ground-water flow in the southern Great Basin typically combined lithostratigraphic units into more general hydrogeologic units that have considerable lateral extent and distinct hydrologic properties. The Late Proterozoic through Lower Cambrian rocks have been treated as a single hydrogeologic unit, named the lower clastic aquitard (Winograd and Thordarson, 1975) or the quartzite confining unitmore » (Laczniak and others, 1996), that serves as the hydrologic basement to the flow system. Although accurate in a general sense, this classification ignores well-established facies relations within these rocks that might increase bedrock permeability and locally influence ground-water flow . This report presents a facies analysis of Late Proterozoic through Lower Cambrian rocks (hereafter called the study interval) in the Death Valley regional ground-water flow system - that portion of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain (fig. 1). The region discussed in this report, hereafter called the study area, covers approximately 100,000 km2 (lat 35 degrees-38 degrees 15'N., long 115 degrees-118 degrees W.). The purpose of this analysis is to provide a general documentation of facies transitions within the Late Proterozoic through Lower Cambrian rocks in order to provide an estimate of material properties (via rock type, grain size, and bedding characteristics) for specific hydrogeologic units to be included in a regional ground-water flow model.« less
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NASA Technical Reports Server (NTRS)
Kuss, Amber; Brandt, William; Randall, Joshua; Floyd, Bridget; Bourai, Abdelwahab; Newcomer, Michelle; Skiles, Joseph; Schmidt, Cindy
2011-01-01
The Gravity Recovery and Climate Experiment (GRACE) measures changes in total water storage (TWS) remotely, and may provide additional insight to the use of well-based data in California's agriculturally productive Central Valley region. Under current California law, well owners are not required to report groundwater extraction rates, making estimation of total groundwater extraction difficult. As a result, other groundwater change detection techniques may prove useful. From October 2002 to September 2009, GRACE was used to map changes in TWS for the three hydrological regions (the Sacramento River Basin, the San Joaquin River Basin, and the Tulare Lake Basin) encompassing the Central Valley aquifer. Net groundwater storage changes were calculated from the changes in TWS for each of the three hydrological regions and by incorporating estimates for additional components of the hydrological budget including precipitation, evapotranspiration, soil moisture, snow pack, and surface water storage. The calculated changes in groundwater storage were then compared to simulated values from the California Department of Water Resource's Central Valley Groundwater- Surface Water Simulation Model (C2VSIM) and their Water Data Library (WDL) Geographic Information System (GIS) change in storage tool. The results from the three methods were compared. Downscaling GRACE data into the 21 smaller Central Valley sub-regions included in C2VSIM was also evaluated. This work has the potential to improve California's groundwater resource management and use of existing hydrological models for the Central Valley.
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2001-10-22
These images of the Saline Valley area, California, were acquired March 30, 2000 and cover a full ASTER scene (60 by 60 km). Each image displays data from a different spectral region, and illustrates the complementary nature of surface compositional information available as a function of wavelength. This image displays visible and near infrared bands 3, 2, and 1 in red, green, and blue (RGB). Vegetation appears red, snow and dry salt lakes are white, and exposed rocks are brown, gray, yellow and blue. Rock colors mainly reflect the presence of iron minerals, and variations in albedo. Figure 1 displays short wavelength infrared bands 4, 6, and 8 as RGB. In this wavelength region, clay, carbonate, and sulfate minerals have diagnostic absorption features, resulting in distinct colors on the image. For example, limestones are yellow-green, and purple areas are kaolinite-rich. Figure 2 displays thermal infrared bands 13, 12 and 10 as RGB. In this wavelength region, variations in quartz content appear as more or less red; carbonate rocks are green, and mafic volcanic rocks are purple. The image is located at 36.8 degrees north latitude and 117.7 degrees west longitude. http://photojournal.jpl.nasa.gov/catalog/PIA11164
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Stock, Greg M.; Luco, Nicolas; Collins, Brian D.; Harp, Edwin L.; Reichenbach, Paola; Frankel, Kurt L.
2014-01-01
Rock falls are common in Yosemite Valley, California, posing substantial hazard and risk to the approximately four million annual visitors to Yosemite National Park. Rock falls in Yosemite Valley over the past few decades have damaged structures and caused injuries within developed regions located on or adjacent to talus slopes highlighting the need for additional investigations into rock-fall hazard and risk. This assessment builds upon previous investigations of rock-fall hazard and risk in Yosemite Valley and focuses on hazard and risk to structures posed by relatively frequent fragmental-type rock falls as large as approximately 100,000 (cubic meters) in volume.
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Jiang, Li; Huang, Tian
2018-04-01
Food poisoning due to wild wasp broods ingestion has long been noted in the upstream region of the Lancang river valley, Yunnan province, China. This study describes the epidemiological and clinical features of the poisoning and possible causes. Surveillance data collected between 2008 and 2016 were analyzed to produce demographic data on patients, information on clinical presentations, wasp species identification, and estimations of possible risk factors for symptomatic cases. Eleven poisoning events were associated with the ingestion of wild wasp broods, including 46 exposed persons with 31 symptomatic living cases and 8 deceased cases that were reported in the Yunnan province between 2008 and 2016. Poisoning cases were only detected in the upstream region of the Lancang river valley in the autumn. The severity of the symptoms was correlated with an evident dose-effect relationship regarding the quantity ingested. The mean latent period from wild wasp broods ingestion to the onset of the symptoms was 10 h for symptomatic living cases and 7 h for deceased cases, respectively. Both gastrointestinal and neurological symptoms were commonly observed in the poisoning cases. The toxin source may be indirectly caused by the wasp broods due to the prevalence of local poisonous plants, such as Tripterygium wilfordii Hook F, Tripterygium hypoglaucum Hutch and Vaccinium bracteatum Thunb. Educational programs at the start of wasp harvest season in September in the high-risk area should be carried out to reduce the incidence of poisonings. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Geomorphic response to tectonically-induced ground deformation in the Wabash Valley
Fraser, G.S.; Thompson, T.A.; Olyphant, G.A.; Furer, L.; Bennett, S.W.
1997-01-01
Numerous low- to moderate-intensity earthquakes have been recorded in a zone of diffuse modern seismicity in southwest Indiana, southeast Illinois, and northernmost Kentucky. Structural elements within the zone include the Wabash Valley Fault System, the LaSalle Anticlinal Belt in western Illinois, and the Rough Creek-Shawneetown Fault System in northern Kentucky. The presence of seismically-induced liquefaction features in the near-surface alluvial sediments in the region indicates that strong ground motion has occurred in the recent geological past, but because the glacial and alluvial sediments in the Wabash Valley appear to be otherwise undisturbed, post-Paleozoic ground deformation resulting from movement on these structural elements has not yet been documented. Morphometric analysis of the land surface, detailed mapping of geomorphic elements in the valley, reconnaissance drilling of the Holocene and Pleistocene alluvium, and structural analysis of the bedrock underlying the valley were used to determine whether the geomorphology of the valley and the patterns of alluviation of the Wabash River were affected by surface deformation associated with the seismic zone during the late Pleistocene and Holocene. Among the observed features in the valley that can be attributed to deformation are: (1) tilting of the modern land surface to the west, (2) preferred channel migration toward the west side of the valley, with concomitant impact on patterns of soil development and sedimentation rate, (3) a convex longitudinal profile of the Wabash River where it crosses the LaSalle Anticlinal Belt, and (4) increased incision of the river into its floodplain downstream from the anticlinal belt.
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NASA Astrophysics Data System (ADS)
Cienciala, P.; Pasternack, G. B.
2017-04-01
Floodplain inundation regime defines hydrological connectivity between river channel and floodplain and thus strongly controls structure and function of these highly diverse and productive ecosystems. We combined an extensive LiDAR data set on topography and vegetation, long-term hydrological records, as well as the outputs of hydrological and two-dimensional hydraulic models to examine how floodplain inundation regimes in a dynamic, regulated, gravel-cobble river in a Mediterranean-climate region are controlled by reach-scale valley morphology, hydroclimatic conditions, and flow regulation. Estimated relative differences in the extent, duration, and cumulative duration of inundation events were often as large as an order of magnitude and generally greatest for large and long duration events. The relative impact of flow regulation was greatest under dry hydroclimatic conditions. Although the effects of hydroclimate and flow impairment are larger than that of valley floor topography, the latter controls sensitivity of floodplain hydroperiod to flow regime changes and should not be ignored. These quantitative estimates of the relative importance of factors that control floodplain processes in Mediterranean, semiarid rivers contributes to better understanding of hydrology and geomorphology of this important class of channels. We also discuss implications of our findings for processes that shape floodplain habitat for riparian vegetation and salmonid fish, especially in the context of ecological restoration.
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Fluvial valleys in the heavily cratered terrains of Mars: Evidence for paleoclimatic change?
NASA Technical Reports Server (NTRS)
Gulick, V. C.; Baker, V. R.
1993-01-01
Whether the formation of the Martian valley networks provides unequivocal evidence for drastically different climatic conditions remains debatable. Recent theoretical climate modeling precludes the existence of a temperate climate early in Mars' geological history. An alternative hypothesis suggests that Mars had a globally higher heat flow early in its geological history, bringing water tables to within 350 m of the surface. While a globally higher heat flow would initiate ground water circulation at depth, the valley networks probably required water tables to be even closer to the surface. Additionally, it was previously reported that the clustered distribution of the valley networks within terrain types, particularly in the heavily cratered highlands, suggests regional hydrological processes were important. The case for localized hydrothermal systems is summarized and estimates of both erosion volumes and of the implied water volumes for several Martian valley systems are presented.
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Ericksen, G.E.; Hosterman, J.W.; St., Amand
1988-01-01
The clay-hill nitrate deposits of the Amargosa River valley, California, are caliche-type accumulations of water-soluble saline minerals in clay-rich soils on saline lake beds of Miocene, Pliocene(?) and Pleistocene age. The soils have a maximum thickness of ??? 50 cm, and commonly consist of three layers: (1) an upper 5-10 cm of saline-free soil; (2) an underlying 15-20 cm of rubbly saline soil; and (3) a hard nitrate-rich caliche, 10-20 cm thick, at the bottom of the soil profile. The saline constituents, which make up as much as 50% of the caliche, are chiefly Cl-, NO-3, SO2-4 and Na+. In addition are minor amounts of K+, Mg2+ and Ca2+, varying, though generally minor, amounts of B2O3 and CO2-3, and trace amounts of I (probably as IO-3), NO-2, CrO2-4 and Mo (probably as MoO2-4). The water-soluble saline materials have an I/Br ratio of ??? 1, which is much higher than nearly all other saline depostis. The principal saline minerals of the caliche are halite (NaCl), nitratite (NaNO3), darapskite (Na3(SO4)(NO3)??H2O), glauberite (Na2Ca(SO4)2), gypsum (CaSO4??2H2O) and anhydrite (CaSO4). Borax (Na2B4O5(OH)4??8H2O), tincalconite (Na2B4O5(OH)4??3H2O) and trona (Na3(CO3)(HCO3)??2H2O) are abundant locally. The clay-hill nitrate deposits are analogous to the well-known Chilean nitrate deposits, and probably are of similar origin. Whereas the Chilean deposits are in permeable soils of the nearly rainless Atacama Desert, the clay-hill deposits are in relatively impervious clay-rich soils that inhibited leaching by rain water. The annual rainfall in the Death Valley region of ??? 5 cm is sufficient to leach water-soluble minerals from the more permeable soils. The clay-hill deposits contain saline materials from the lake beds beneath the nitrate deposits are well as wind-transported materials from nearby clay-hill soils, playas and salt marshes. The nitrate is probably of organic origin, consisting of atmospheric nitrogen fixed as protein by photoautotrophic blue-green algae
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Lamontagne, Jonathan R.; Stedinger, Jery R.; Berenbrock, Charles; Veilleux, Andrea G.; Ferris, Justin C.; Knifong, Donna L.
2012-01-01
Flood-frequency information is important in the Central Valley region of California because of the high risk of catastrophic flooding. Most traditional flood-frequency studies focus on peak flows, but for the assessment of the adequacy of reservoirs, levees, other flood control structures, sustained flood flow (flood duration) frequency data are needed. This study focuses on rainfall or rain-on-snow floods, rather than the annual maximum, because rain events produce the largest floods in the region. A key to estimating flood-duration frequency is determining the regional skew for such data. Of the 50 sites used in this study to determine regional skew, 28 sites were considered to have little to no significant regulated flows, and for the 22 sites considered significantly regulated, unregulated daily flow data were synthesized by using reservoir storage changes and diversion records. The unregulated, annual maximum rainfall flood flows for selected durations (1-day, 3-day, 7-day, 15-day, and 30-day) for all 50 sites were furnished by the U.S. Army Corps of Engineers. Station skew was determined by using the expected moments algorithm program for fitting the Pearson Type 3 flood-frequency distribution to the logarithms of annual flood-duration data. Bayesian generalized least squares regression procedures used in earlier studies were modified to address problems caused by large cross correlations among concurrent rainfall floods in California and to address the extensive censoring of low outliers at some sites, by using the new expected moments algorithm for fitting the LP3 distribution to rainfall flood-duration data. To properly account for these problems and to develop suitable regional-skew regression models and regression diagnostics, a combination of ordinary least squares, weighted least squares, and Bayesian generalized least squares regressions were adopted. This new methodology determined that a nonlinear model relating regional skew to mean basin elevation
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Examining Dimethyl Sulfide Emissions in California's San Joaquin Valley
NASA Astrophysics Data System (ADS)
Huber, D.; Hughes, S.; Blake, D. R.
2017-12-01
Dimethyl Sulfide (DMS) is a sulfur-containing compound that leads to the formation of aerosols which can lead to the formation of haze and fog. Whole air samples were collected on board the NASA C-23 Sherpa aircraft during the 2017 Student Airborne Research Program (SARP) over dairies and agricultural fields in the San Joaquin Valley. Analysis of the samples indicate average DMS concentrations of 23 ± 9 pptv, with a maximum concentration of 49 pptv. When compared with DMS concentrations from previous SARP missions (2009-2016), 2017 by far had the highest frequency of elevated DMS in this region. For this study, agricultural productivity of this region was analyzed to determine whether land use could be contributing to the elevated DMS. Top down and bottom up analysis of agriculture and dairies were used to determine emission rates of DMS in the San Joaquin Valley. Correlations to methane and ethanol were used to determine that DMS emissions were strongly linked to dairies, and resulted in R2 values of 0.61 and 0.43, respectively. These values indicate a strong correlation between dairies and DMS emissions. Combined with NOAA HySPLIT back trajectory data and analysis of ground air samples, results suggest that the contribution of dairies to annual DMS emissions in the San Joaquin Valley exceeds those from corn and alfalfa production.
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Observation of acoustic valley vortex states and valley-chirality locked beam splitting
NASA Astrophysics Data System (ADS)
Ye, Liping; Qiu, Chunyin; Lu, Jiuyang; Wen, Xinhua; Shen, Yuanyuan; Ke, Manzhu; Zhang, Fan; Liu, Zhengyou
2017-05-01
We report an experimental observation of the classical version of valley polarized states in a two-dimensional hexagonal sonic crystal. The acoustic valley states, which carry specific linear momenta and orbital angular momenta, were selectively excited by external Gaussian beams and conveniently confirmed by the pressure distribution outside the crystal, according to the criterion of momentum conservation. The vortex nature of such intriguing bulk crystal states was directly characterized by scanning the phase profile inside the crystal. In addition, we observed a peculiar beam-splitting phenomenon, in which the separated beams are constructed by different valleys and locked to the opposite vortex chirality. The exceptional sound transport, encoded with valley-chirality locked information, may serve as the basis of designing conceptually interesting acoustic devices with unconventional functions.
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2009-11-02
The McMurdo Dry Valleys are a row of valleys west of McMurdo Sound, Antarctica. They are so named because of their extremely low humidity and lack of snow and ice cover. This image was acquired December 8, 2002 by NASA Terra spacecraft.
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NASA Technical Reports Server (NTRS)
Massman, W. J.; Pederson, J.; Delany, A.; Grantz, D.; Hertog, G. Den; Neumann, H. H.; Oncley, S. P.; Pearson, R., Jr.; Shaw, R. H.
1994-01-01
Plants and soils act as major sinks for the destruction of tropospheric ozone, especially during daylight hours when plant stomata open and are thought to provide the dominant pathway for the uptake of ozone. The present study, part of the California Ozone Deposition Experiment, compares predictions of the regional acid deposition model ozone surface conductance module with surface conductance data derived from eddy covariance measurements of ozone flux taken at a grape, a cotton, and a grassland site in the San Joaquin Valley of California during the summer of 1991. Results indicate that the model (which was developed to provide long-term large-area estimates for the eastern United States) significantly overpredicts the surface conductance at all times of the day for at least two important types of plant cover of the San Joaquin Valley and that it incorrectly partitions the ozone flux between transpiring and nontranspiring components of the surface at the third site. Consequently, the model either overpredicts or inaccurately represents the observed deposition velocities. Other results indicate that the presence of dew does not reduce the rate of ozone deposition, contradicting to model assumptions, and that model assumptions involving the dependency of stomata upon environmental temperature are unnecessary. The effects of measurement errors and biases, arising from the presence of the roughness sublayer and possible photochemical reactions, are also discussed. A simpler model for ozone surface deposition (at least for the San Joaquin Valley) is proposed and evaluated.
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Deep groundwater and potential subsurface habitats beneath an Antarctic dry valley
Mikucki, J. A.; Auken, E.; Tulaczyk, S.; Virginia, R. A.; Schamper, C.; Sørensen, K. I.; Doran, P. T.; Dugan, H.; Foley, N.
2015-01-01
The occurrence of groundwater in Antarctica, particularly in the ice-free regions and along the coastal margins is poorly understood. Here we use an airborne transient electromagnetic (AEM) sensor to produce extensive imagery of resistivity beneath Taylor Valley. Regional-scale zones of low subsurface resistivity were detected that are inconsistent with the high resistivity of glacier ice or dry permafrost in this region. We interpret these results as an indication that liquid, with sufficiently high solute content, exists at temperatures well below freezing and considered within the range suitable for microbial life. These inferred brines are widespread within permafrost and extend below glaciers and lakes. One system emanates from below Taylor Glacier into Lake Bonney and a second system connects the ocean with the eastern 18 km of the valley. A connection between these two basins was not detected to the depth limitation of the AEM survey (∼350 m). PMID:25919365
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NASA Astrophysics Data System (ADS)
Masoud, Alaa A.; El-Horiny, Mohamed M.; Atwia, Mohamed G.; Gemail, Khaled S.; Koike, Katsuaki
2018-06-01
Salinization of groundwater and soil resources has long been a serious environmental hazard in arid regions. This study was conducted to investigate and document the factors controlling such salinization and their inter-relationships in the Dakhla Oasis (Egypt). To accomplish this, 60 groundwater samples and 31 soil samples were collected in February 2014. Factor analysis (FA) and hierarchical cluster analysis (HCA) were integrated with geostatistical analyses to characterize the chemical properties of groundwater and soil and their spatial patterns, identify the factors controlling the pattern variability, and clarify the salinization mechanism. Groundwater quality standards revealed emergence of salinization (av. 885.8 mg/L) and extreme occurrences of Fe2+ (av. 17.22 mg/L) and Mn2+ (av. 2.38 mg/L). Soils were highly salt-affected (av. 15.2 dS m-1) and slightly alkaline (av. pH = 7.7). Evaporation and ion-exchange processes governed the evolution of two main water types: Na-Cl (52%) and Ca-Mg-Cl (47%), respectively. Salinization leads the chemical variability of both resources. Distinctive patterns of slight salinization marked the northern part and intense salinization marked the middle and southern parts. Congruence in the resources clusters confirmed common geology, soil types, and urban and agricultural practices. Minimizing the environmental and socioeconomic impacts of the resources salinization urges the need for better understanding of the hydrochemical characteristics and prediction of quality changes.
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Plevinsky, Jill M; Greenley, Rachel N
2014-09-01
Youth with inflammatory bowel diseases are at risk for impaired health-related quality of life (HRQoL) and problems with social functioning. This study examined the impact of attending Camp Oasis (a disease-specific weeklong camp experience) on the HRQoL and social functioning of youth with inflammatory bowel diseases. Additionally, the study collected pilot data on whether a postcamp Facebook group contributed to maintenance or enhancement of these factors. Twenty-one youth ages 14 to 17 years who attended Camp Oasis and were Facebook users participated. HRQoL and social functioning (i.e., social support and social connectedness) were assessed through validated youth-report questionnaires at precamp, postcamp, and post-Facebook group. The Facebook group was 8 weeks in duration and encouraged campers to continue interacting in a private, protected setting. Analyses of effect sizes (i.e., Cohen's d) indicated medium and statistically significant increases in HRQoL from precamp to postcamp (d = 0.40) and small increases in social functioning (d = 0.15-0.24). Additional improvements in social functioning were seen from postcamp to post-Facebook group (d = 0.21-0.32), and overall improvements were observed in all domains (d = 0.17-0.52). Findings replicated those of previous research in documenting the value of Camp Oasis on enhancing HRQoL. Both the camp experience and the Facebook group contributed to improvements in youth social functioning. Thus, supplementing the camp experience with membership in an online community may enhance social functioning in adolescents with inflammatory bowel diseases.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-09
... micrometers (PM 10 ) submitted by the State of Alaska on May 8, 2009 for the Mendenhall Valley nonattainment area (Mendenhall Valley NAA), and the State's request to redesignate the area to attainment for the... comments. Email: [email protected] Mail: Mr. Keith Rose, U.S. EPA Region 10, Office of Air, Waste...
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Susan D. Olberding; Karen Malis-Clark; Peter J. Pilles; Dennis Lund
2008-01-01
This poster presents the continuing cooperative relationship between the Fort Valley Experimental Forest (FVEF), Coconino National Forest (CNF), USFS Region 3, and the long-term partnerships with the Museum of the Northern Arizona and the NAU School of Forestry.Fort Valley was initially named the Coconino Experiment Station and funds were channeled...
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The Aosta Valley Astronomical Observatory
NASA Astrophysics Data System (ADS)
Carbognani, A.
2011-06-01
OAVdA stands for Astronomical Observatory of the Autonomous Region of the Aosta Valley (Italy). The centre is located in the northwestern Italian Alps, near the border with France and Switzerland (Lat: 45° 47' 22" N, Long: 7° 28' 42" E), at 1675 m above sea level in the Saint-Barthélemy Valley and is managed by the "Fondazione Clément Fillietroz", with funding from local administrations. OAVdA was opened in 2003 as a centre for the popularization of astronomy but, since 2006, the main activity has been scientific research, as a consequence of an official cooperation agreement established with the Italian National Institute for Astrophysics (INAF). In 2009, a planetarium was built near the observatory with a 10-meter dome and 67 seats, which is currently used for educational astronomy. In the year 2009 about 15,200 people visited OAVdA and the planetarium. The staff in 2010 was made up of 12 people, including a scientific team of 5 physicists and astronomers on ESF (European Social Fund) grants and permanently residing at the observatory.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
None
A companion report, DOE/ET-0064/1, presents a geographic, cultural, and demographic profile of the Tennessee Valley Region study area. This report describes the calculations of radionuclide release and transport and of the resultant dose to the regional population, assuming a projected installed capacity of 220,000 MW in the year 2000, of which 144,000 MW would be nuclear. All elements of the fuel cycle were assumed to be in operation. The radiological dose was calculated as a one-year dose based on ingestion of 35 different food types as well as for nine non-food pathways, and was reported as dose to the totalmore » body and for six specific organs for each of four age groups (infant, child, teen, and adult). Results indicate that the average individual would receive an incremental dose of 7 x 10/sup -4/ millirems in the year 2000 from the operation of nuclear facilities within and adjacent to the region, five orders of magnitude smaller than the dose from naturally occurring radiation in the area. The major contributor to dose was found to be tritium, and the most significant pathways were immersion in air, inhalation of air, transpiration of tritium (absorption through the skin), and exposure radionuclide-containing soil. 60 references.« less
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Vignon, Eric; Valat, Jean-Pierre; Rossignol, Michel; Avouac, Bernard; Rozenberg, Sylvie; Thoumie, Philippe; Avouac, Jérôme; Nordin, Margareta; Hilliquin, Pascal
2006-07-01
The goal of this study was to determine which activities in four domains, daily life, exercises, sports and occupational activities, should be recommended, in favor or against, for the patient suffering from knee or hip OA. Scientific literature was searched in Medline, Embase and Cochrane databases for articles in French or English, reporting original data. The articles were evaluated with standardized epidemiological criteria. Seventy-two articles were retained. Recommendations were graded according to the level of scientific evidence (A high, B moderate, C clinical consensus) and were formulated for primary care. For activity of daily life (ADL), the OASIS group states with a moderate level of scientific evidence, that ADL are a risk factor for knee OA and that risk increases with intensity and duration of activity. The group concludes that healthy subjects as well as OA patients in general can pursue a high level of physical activity, provided the activity is not painful and does not predispose to trauma (grade B). Radiographic or clinical OA is not a contraindication to promoting activity in patients who have a sedentary lifestyle (grade C). For exercises and other structured activities pursued with a goal of health improvement, the group states with a high level of scientific evidence that they have a favourable effect on pain and function in the sedentary knee OA patient. The OASIS group recommends the practice of exercises and other structured activities for the sedentary patient with knee OA (grade A). Static exercises are not favored over dynamic exercises, availability, preference and tolerance being the criteria for the choice of an exercise (grade A). As results deteriorate when exercises are stopped, they should be performed at a frequency of between one and three times per week (grade B). Professional assistance can be useful in improving initial compliance and perseverance (grade B). There is no scientific argument to support halting exercise in
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Ground-water conditions in southern Utah Valley and Goshen Valley, Utah
Cordova, R.M.
1970-01-01
The investigation of ground-water conditions in southern Utah Valley and Goshen Valley, Utah, was made by the U. S. Geological Survey as part of a cooperative program with the Utah Department of Natural Resources, Division of Water Rights, to investigate the water resources of the State. The purposes of the investigation were to (1) determine the occurrence, recharge, discharge, movement, storage, chemical quality, and availability of ground water; (2) appraise the effects of increased withdrawal of water from wells; and (3) evaluate the effect of the Central Utah Project on the ground-water reservoir and the water supply of Utah Lake.This report presents a description of the aquifer system in the two valleys, a detailed description of the ground-water resources, and conclusions about potential development and its effect on the hydrologic conditions in the valleys. Two supplementary reports are products of the investigation. A basic-data release (Cordova, 1969) contains most of the basic data collected for the investigation, including well characteristics, drillers' logs, water levels, pumpage from wells, chemical analyses of ground and surface waters, and discharge of selected springs, drains, and streams. An interpretive report (Cordova and Mower, 1967) contains the results of a large-scale aquifer test in southern Utah Valley.
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Riley, P.; Tikoff, B.; Hildreth, Wes
2012-01-01
The Long Valley region of eastern California (United States) is the site of abundant late Tertiary–present magmatism, including three geochemically distinct stages of magmatism since ca. 3 Ma: Mammoth Mountain, the Mono-Inyo volcanic chain, and Long Valley Caldera. We propose two tectonic models, one explaining the Mammoth Mountain–Mono-Inyo magmatism and the other explaining the presence of Long Valley Caldera. First, the ongoing Mammoth Mountain–Mono-Inyo volcanic chain magmatism is explained by a ridge-transform-ridge system, with the Mono-Inyo volcanic chain acting as one ridge segment and the South Moat fault acting as a transform fault. Implicit in this first model is that this region of eastern California is beginning to act as an incipient plate boundary. Second, the older Long Valley Caldera system is hypothesized to occur in a region of enhanced extension resulting from regional fault block rotation, specifically involving activation of the sinistral faults of the Mina deflection. The tectonic models are consistent with observed spatial and temporal differences in the geochemistry of the regional magmas, and the westward progression of magmatism since ca. 12 Ma.
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Silvani, Ludovica; Riccardi, Carmela; Eek, Espen; Papini, Marco Petrangeli; Morin, Nicolas A O; Cornelissen, Gerard; Oen, Amy M P; Hale, Sarah E
2017-10-01
Polar organic chemical integrative samplers (POCIS) have previously been used to monitor alkylphenol (AP) contamination in water and produced water. However, only the sorbent receiving phase of the POCIS (Oasis beads) is traditionally analyzed, thus limiting the use of POCIS for monitoring a range of APs with varying hydrophobicity. Here a "pharmaceutical" POCIS was calibrated in the laboratory using a static renewal setup for APs (from 2-ethylphenol to 4-n-nonylphenol) with varying hydrophobicity (log K ow between 2.47 and 5.76). The POCIS sampler was calibrated over its 28 day integrative regime and sampling rates (R s ) were determined. Uptake was shown to be a function of AP hydrophobicity where compounds with log K ow < 4 were preferentially accumulated in Oasis beads, and compounds with log K ow > 5 were preferentially accumulated in the PES membranes. A lag phase (over a 24 h period) before uptake in to the PES membranes occurred was evident. This work demonstrates that the analysis of both POCIS phases is vital in order to correctly determine environmentally relevant concentrations owing to the fact that for APs with log K ow ≤ 4 uptake, to the PES membranes and the Oasis beads, involves different processes compared to APs with log K ow ≥ 4. The extraction of both the POCIS matrices is thus recommended in order to assess the concentration of hydrophobic APs (log K ow ≥ 4), as well as hydrophilic APs, most effectively. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
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Arctic springtime observations of volatile organic compounds during the OASIS-2009 campaign
NASA Astrophysics Data System (ADS)
Hornbrook, Rebecca S.; Hills, Alan J.; Riemer, Daniel D.; Abdelhamid, Aroob; Flocke, Frank M.; Hall, Samuel R.; Huey, L. Gregory; Knapp, David J.; Liao, Jin; Mauldin, Roy L.; Montzka, Denise D.; Orlando, John J.; Shepson, Paul B.; Sive, Barkley; Staebler, Ralf M.; Tanner, David. J.; Thompson, Chelsea R.; Turnipseed, Andrew; Ullmann, Kirk; Weinheimer, Andrew J.; Apel, Eric C.
2016-08-01
Gas-phase volatile organic compounds (VOCs) were measured at three vertical levels between 0.6 m and 5.4 m in the Arctic boundary layer in Barrow, Alaska, for the Ocean-Atmosphere-Sea Ice-Snowpack (OASIS)-2009 field campaign during March-April 2009. C4-C8 nonmethane hydrocarbons (NMHCs) and oxygenated VOCs (OVOCs), including alcohols, aldehydes, and ketones, were quantified multiple times per hour, day and night, during the campaign using in situ fast gas chromatography-mass spectrometry. Three canister samples were also collected daily and subsequently analyzed for C2-C5 NMHCs. The NMHCs and aldehydes demonstrated an overall decrease in mixing ratios during the experiment, whereas acetone and 2-butanone showed increases. Calculations of time-integrated concentrations of Br atoms, ∫[Br]dt, yielded values as high as (1.34 ± 0.27) × 1014 cm-3 s during the longest observed ozone depletion event (ODE) of the campaign and were correlated with the steady state Br calculated at the site during this time. Both chlorine and bromine chemistry contributed to the large perturbations on the production and losses of VOCs. Notably, acetaldehyde, propanal, and butanal mixing ratios dropped below the detection limit of the instrument (3 parts per trillion by volume (pptv) for acetaldehyde and propanal, 2 pptv for butanal) during several ODEs due to Br chemistry. Chemical flux calculations of OVOC production and loss are consistent with localized high Cl-atom concentrations either regionally or within a very shallow surface layer, while the deeper Arctic boundary layer provides a continuous source of precursor alkanes to maintain the OVOC mixing ratios.
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Relating coccidioidomycosis (Valley Fever) incidence via to soil moisture conditions
USDA-ARS?s Scientific Manuscript database
Coccidioidomycosis (also called Valley fever) is caused by a soil-borne fungus, Coccidioides spp., in arid regions of the southwestern United States. Though some who develop infections from this fungus remain asymptomatic, others develop respiratory disease as a consequence. Less commonly, severe ...
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Nearing the cold-arid limits of microbial life in permafrost of an upper dry valley, Antarctica.
Goordial, Jacqueline; Davila, Alfonso; Lacelle, Denis; Pollard, Wayne; Marinova, Margarita M; Greer, Charles W; DiRuggiero, Jocelyn; McKay, Christopher P; Whyte, Lyle G
2016-07-01
Some of the coldest and driest permafrost soils on Earth are located in the high-elevation McMurdo Dry Valleys (MDVs) of Antarctica, but little is known about the permafrost microbial communities other than that microorganisms are present in these valleys. Here, we describe the microbiology and habitable conditions of highly unique dry and ice-cemented permafrost in University Valley, one of the coldest and driest regions in the MDVs (1700 m above sea level; mean temperature -23 °C; no degree days above freezing), where the ice in permafrost originates from vapour deposition rather than liquid water. We found that culturable and total microbial biomass in University Valley was extremely low, and microbial activity under ambient conditions was undetectable. Our results contrast with reports from the lower-elevation Dry Valleys and Arctic permafrost soils where active microbial populations are found, suggesting that the combination of severe cold, aridity, oligotrophy of University Valley permafrost soils severely limit microbial activity and survival.
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Nearing the cold-arid limits of microbial life in permafrost of an upper dry valley, Antarctica
Goordial, Jacqueline; Davila, Alfonso; Lacelle, Denis; Pollard, Wayne; Marinova, Margarita M; Greer, Charles W; DiRuggiero, Jocelyn; McKay, Christopher P; Whyte, Lyle G
2016-01-01
Some of the coldest and driest permafrost soils on Earth are located in the high-elevation McMurdo Dry Valleys (MDVs) of Antarctica, but little is known about the permafrost microbial communities other than that microorganisms are present in these valleys. Here, we describe the microbiology and habitable conditions of highly unique dry and ice-cemented permafrost in University Valley, one of the coldest and driest regions in the MDVs (1700 m above sea level; mean temperature −23 °C; no degree days above freezing), where the ice in permafrost originates from vapour deposition rather than liquid water. We found that culturable and total microbial biomass in University Valley was extremely low, and microbial activity under ambient conditions was undetectable. Our results contrast with reports from the lower-elevation Dry Valleys and Arctic permafrost soils where active microbial populations are found, suggesting that the combination of severe cold, aridity, oligotrophy of University Valley permafrost soils severely limit microbial activity and survival. PMID:27323892
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Castle, Robert O.; Gilmore, Thomas D.; Walker, James P.; Castle, Susan A.
2005-01-01
Comparisons among repeated levelings along selected lines through the Death Valley region of California and adjacent parts of Nevada have disclosed surprisingly large vertical displacements. The vertical control data in this lightly populated area is sparse; moreover, as much as a third of the recovered data is so thoroughly contaminated by systematic error and survey blunders that no attempt was made to correct these data and they were simply discarded. In spite of these limitations, generally episodic, commonly large vertical displacements are disclosed along a number of lines. Displacements in excess of 0.4 m, with respect to our selected control point at Beatty, Nevada, and differential displacements of about 0.7 m apparently occurred during the earlier years of the 20th century and continued episodically through at least 1943. While this area contains abundant evidence of continuing tectonic activity through latest Quaternary time, it is virtually devoid of historic seismicity. We have detected no clear connection between the described vertical displacements and fault zones reportedly active during Holocene time, although we sense some association with several more broadly defined tectonic features.
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Analysis of Mining-induced Valley Closure Movements
NASA Astrophysics Data System (ADS)
Zhang, C.; Mitra, R.; Oh, J.; Hebblewhite, B.
2016-05-01
Valley closure movements have been observed for decades in Australia and overseas when underground mining occurred beneath or in close proximity to valleys and other forms of irregular topographies. Valley closure is defined as the inward movements of the valley sides towards the valley centreline. Due to the complexity of the local geology and the interplay between several geological, topographical and mining factors, the underlying mechanisms that actually cause this behaviour are not completely understood. A comprehensive programme of numerical modelling investigations has been carried out to further evaluate and quantify the influence of a number of these mining and geological factors and their inter-relationships. The factors investigated in this paper include longwall positional factors, horizontal stress, panel width, depth of cover and geological structures around the valley. It is found that mining in a series passing beneath the valley dramatically increases valley closure, and mining parallel to valley induces much more closure than other mining orientations. The redistribution of horizontal stress and influence of mining activity have also been recognised as important factors promoting valley closure, and the effect of geological structure around the valley is found to be relatively small. This paper provides further insight into both the valley closure mechanisms and how these mechanisms should be considered in valley closure prediction models.
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The Inter-Valley Soil Comparative Survey: the ecology of Dry Valley edaphic microbial communities
Lee, Charles K; Barbier, Béatrice A; Bottos, Eric M; McDonald, Ian R; Cary, Stephen Craig
2012-01-01
Recent applications of molecular genetics to edaphic microbial communities of the McMurdo Dry Valleys and elsewhere have rejected a long-held belief that Antarctic soils contain extremely limited microbial diversity. The Inter-Valley Soil Comparative Survey aims to elucidate the factors shaping these unique microbial communities and their biogeography by integrating molecular genetic approaches with biogeochemical analyses. Although the microbial communities of Dry Valley soils may be complex, there is little doubt that the ecosystem's food web is relatively simple, and evidence suggests that physicochemical conditions may have the dominant role in shaping microbial communities. To examine this hypothesis, bacterial communities from representative soil samples collected in four geographically disparate Dry Valleys were analyzed using molecular genetic tools, including pyrosequencing of 16S rRNA gene PCR amplicons. Results show that the four communities are structurally and phylogenetically distinct, and possess significantly different levels of diversity. Strikingly, only 2 of 214 phylotypes were found in all four valleys, challenging a widespread assumption that the microbiota of the Dry Valleys is composed of a few cosmopolitan species. Analysis of soil geochemical properties indicated that salt content, alongside altitude and Cu2+, was significantly correlated with differences in microbial communities. Our results indicate that the microbial ecology of Dry Valley soils is highly localized and that physicochemical factors potentially have major roles in shaping the microbiology of ice-free areas of Antarctica. These findings hint at links between Dry Valley glacial geomorphology and microbial ecology, and raise previously unrecognized issues related to environmental management of this unique ecosystem. PMID:22170424
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Code of Federal Regulations, 2010 CFR
2010-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rogue Valley. 9.132... Rogue Valley. (a) Name. The name of the viticultural area described in this section is “Rouge Valley.” (b) Approved map. The appropriate map for determining the boundaries of the Rogue Valley viticultural...
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USDA-ARS?s Scientific Manuscript database
With over 4 million ha irrigated cropland, the Lower Mississippi River Valley (LMRV) is a highly productive agricultural region where irrigation practices are similar and the Mississippi River Valley alluvial aquifer (MRVA) is a primary source of on-demand irrigation. Owing to agricultural exports, ...
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Geophysical interpretations west of and within the northwestern part of the Nevada Test Site
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grauch, V.J.; Sawyer, D.A.; Fridrich, C.J.
1997-12-31
This report focuses on interpretation of gravity and new magnetic data west of the Nevada Test Site (NTS) and within the northwestern part of NTS. The interpretations integrate the gravity and magnetic data with other geophysical, geological, and rock property data to put constraints on tectonic and magmatic features not exposed at the surface. West of NTS, where drill hole information is absent, these geophysical data provide the best available information on the subsurface. Interpreted subsurface features include calderas, intrusions, basalt flows and volcanoes, Tertiary basins, structurally high pre-Tertiary rocks, and fault zones. New features revealed by this study includemore » (1) a north-south buried tectonic fault east of Oasis Mountain, which the authors call the Hogback fault; (2) an east striking fault or accommodation zone along the south side of Oasis Valley basin, which they call the Hot Springs fault; (3) a NNE striking structural zone coinciding with the western margins of the caldera complexes; (4) regional magnetic highs that probably represent a thick sequence of Tertiary volcanic rocks; and (5) two probable buried calderas that may be related to the tuffs of Tolicha Peak and of Sleeping Butte, respectively.« less
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Microbial extremophiles from the 2008 Schirmacher Oasis Expedition: preliminary results
NASA Astrophysics Data System (ADS)
Hoover, Richard B.; Pikuta, Elena V.; Townsend, Alisa; Anthony, Joshua; Guisler, Melissa; McDaniel, Jasmine; Bej, Asim; Storrie-Lombardi, Michael
2008-08-01
Among the most interesting targets for Astrobiology research are the polar ice caps and the permafrost of Mars and the ice and liquid water bodies that may lie beneath the frozen crusts of comets, the icy moons of Jupiter (Europa, Io and Ganymede) and Saturn (Titan and Enceladus). The permanently ice-covered lakes of Antarctica, such as Lake Vostok and Lake Untersee, provide some of the best terrestrial analogues for these targets. The 2008 International Tawani Schirmacher Oasis/Lake Untersee Expeditions have been organized to conduct studies of novel microbial extremophiles and investigate the biodiversity of the glaciers and ice-covered lakes of Dronning Maud Land, East Antarctica. This paper describes the preliminary analysis of the anaerobic microbial extremophiles isolated from samples collected during the 2008 International Schirmacher Oasis Antarctica Reconnaissance Expedition. These samples showed great diversity of psychrophlic and psychrotolerant bacteria. Six new anaerobic strains have been isolated in pure cultures and partially characterized. Two of them (strains ARHSd-7G and ARHSd-9G) were isolated from a small tidal pool near the colony of African Penguins Spheniscus demersus. Strain ARHSd-7G was isolated on mineral anaerobic medium with 3 % NaCl, pH 7 and D-glucose, it has motile, vibrion shape cells, and is Gram variable. Strain ARHSd-9G grew on anaerobic, alkaline medium with pH 9 and 1 % NaCl at 3°C. The substrate was D-glucose supplemented with yeast extract (0.05 %). Cells of strain ARHSd-9G had morphology of straight or slightly curved elongated rods and demonstrated unusual optical effects under dark-field visible light microscopy. The cells were spore-forming and Gram positive. From the mat sample collected near Lake Zub, the new strain LZ-3 was isolated in pure culture at 3°C. Strain LZ-3 was anaerobic and grew on 0.5 % NaCl mineral medium with Dglucose as a substrate. The gram positive cells were spore-forming. They exhibited a
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Surface Sediment Geochemistry in and around the Hudson Shelf Valley Offshore of New York
NASA Astrophysics Data System (ADS)
Mecray, E. L.; ten Brink, M. B.; Butman, B.; Denny, J.; Murray, R. W.
2001-05-01
The Hudson Shelf Valley, an ancient submerged portion of the Hudson River, extends across the continental shelf offshore of New York and New Jersey. Between 1959 and 1987, the area near the head of the valley was used for disposal of approximately 1.20 x 108 m3 of dredged material and sewage sludge. The distribution of metal concentrations and sediment characteristics were used to investigate the transport and fate of the sediments and their associated contaminants. Surface (0-2cm) sediments collected at 440 stations throughout the New York Bight between 1993 and 1998 were used to establish the regional distribution of pollutant metals, grain size, organic carbon, and Clostridium perfringens spores. Sediments in the New York Bight are generally sandy, however fine-grained sediments are found in the axis of the Valley. Statistical methods identified common sources and chemical mobility within groups of anthropogenic and naturally-occurring elements. High metal concentrations, fine-grained sediments, and higher organic carbon concentrations co-occur in depo-centers within the Valley. Normalization of the metal concentrations to these factors shows higher metal concentrations on the fine-grained particles in sandy areas of the Bight, particularly along the southern shore of Long Island. These distributions have implications for evaluating the impact of the mass distribution for contaminated metals in different habitats and areas. Decreasing concentrations of pollutants with time are observed, reflecting reduced contaminant loading in the upper region of the Valley; however, concentrations are still above natural background levels.
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Scaling the Morphology of Sapping and Pressurized Groundwater Experiments to Martian Valleys
NASA Astrophysics Data System (ADS)
Marra, W. A.; Kleinhans, M. G.
2013-12-01
Various valleys exist on Mars, which shows the former existence of fluvial activity and thus liquid water at the surface. Although these valleys show similarities with some valleys on Earth, many morphological features are unique for Mars or are very rare on Earth. Therefore, we lack knowledge about the formative processes of these enigmatic valleys. In this study, we explored possible groundwater scenarios for the formation of these valleys using flume experiments, as there are no pure Earth analogues for these systems. We aim to infer their formative processes from morphological properties. A series of flume experiments were carried out in a 4x6x1 m experimental setup, where we observed the valley formation as result from seeping groundwater by both local and distal groundwater sources and by pressurized groundwater release. Time-lapse imagery and DEMs of the experiments show the morphological development, associated processes, and landscape evolution. Indicators of the processes where we particularly looked at were changes in valley slope, cross-sectional shape, the relations between valley dimensions, and regional landscape properties as drainage density and valley size distributions. Hydrological modelling assists in scaling the observed experimental features to real-world systems. Additionally, we looked at valleys on Earth in the Atacama Desert, at Box canyon in Idaho, valleys around Kohala on Hawaii and Apalachicola bluffs in Florida to test the applicability of our methods to real-world systems. In the seeping groundwater valleys, valleys develop due to a combination of mass-wasting failures, mudflows and fluvial flow. The latter two processes are expressed in the final morphology by a break in slope. The mass wasting processes result in U-shaped valleys, which are more pronounced in distal groundwater cases. However, in real-world cases of similar shaped valleys, the cross-sectional shape seems strongly influenced by the strength of the material as well
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NASA Astrophysics Data System (ADS)
Xie, Yaowen; Wang, Guisheng; Wang, Xueqiang; Fan, Peilei
2017-12-01
Oasis evolution, one of the most obvious surface processes in arid regions, affects various aspects of the regional environment, such as hydrological processes, ecological conditions, and microclimates. In this paper, the historical spatio-temporal evolution of the cultivated oases in the Heihe River Basin, the second largest inland watershed in the northwest of China, was assessed using multidisciplinary methods and data from multiple sources, including historical literature, ancient sites, maps and remotely sensed images. The findings show that cultivated oases were first developed on a large scale during the Han Dynasty (121 BC-220) and then gradually decreased in extent from the Six Dynasties period (220-581) to the Sui-Tang period (581-907), reaching a minimum in the Song-Yuan period (960-1368). An abrupt revival occurred during the Ming Dynasty (1368-1644) and continued through the Qing Dynasty (1644-1911), and during the period of the Republic of China (1912-1949), oasis development reached its greatest peak of the entire historical period. The oasis areas during seven major historical periods, i.e., Han, Six Dynasties, Sui-Tang, Song-Yuan, Ming, Qing, and Republic of China, are estimated to have been 1703 km2, 1115 km2, 629 km2, 614 km2, 964 km2, 1205 km2, and 1917 km2, respectively. The spatial distribution generally exhibited a continuous sprawl process, with the center of the oases moving gradually from the downstream region to the middle and even upstream regions. The oases along the main river remained stable during most periods, whereas those close to the terminal reaches were subject to frequent variations and even abandonment. Socio-economic factors were the main forces driving the evolution of cultivated oases in the area; among them, political and societal stability, national defense, agricultural policy, population, and technological progress were the most important.
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NASA Astrophysics Data System (ADS)
Tebbs, E. J.; Remedios, J. J.; Avery, S. T.; Rowland, C. S.; Harper, D. M.
2015-08-01
In situ reflectance measurements and Landsat satellite imagery were combined to develop an optical classification scheme for alkaline-saline lakes in the Eastern Rift Valley. The classification allows the ecological state and consequent value, in this case to Lesser Flamingos, to be determined using Landsat satellite imagery. Lesser Flamingos depend on a network of 15 alkaline-saline lakes in East African Rift Valley, where they feed by filtering cyanobacteria and benthic diatoms from the lakes' waters. The classification developed here was based on a decision tree which used the reflectance in Landsat ETM+ bands 2-4 to assign one of six classes: low phytoplankton biomass; suspended sediment-dominated; microphytobenthos; high cyanobacterial biomass; cyanobacterial scum and bleached cyanobacterial scum. The classification accuracy was 77% when verified against in situ measurements. Classified imagery and timeseries were produced for selected lakes, which show the different ecological behaviours of these complex systems. The results have highlighted the importance to flamingos of the food resources offered by the extremely remote Lake Logipi. This study has demonstrated the potential of high spatial resolution, low spectral resolution sensors for providing ecologically valuable information at a regional scale, for alkaline-saline lakes and similar hypereutrophic inland waters.
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NASA Astrophysics Data System (ADS)
Zambrano-Garcia, A.; López-Veneroni, D.; Rojas, A.; Torres, A.; Sosa, G.
2007-05-01
As a part of the MILAGRO Field Campaign 2006, the influence of anthropogenic sources to metal air pollution in the Mezquital Valley, Hidalgo State, was explored by biomonitoring techniques. This valley is a major industrial- agriculture area located in central Mexico. An oil refinery, an electrical power plant, several cement plants with open-pit mines, as well as intensive wastewater-based agricultural areas, all within a 50 km radius, are some of the most important local sources of particulate air pollution. The concentrations of 25 metals and elements were determined by ICP-AES (EPA 610C method) for triplicate composite samples of the "ball moss" (T. recurvata ) collected at 50 sites. In addition, the ratios of two stable isotopes ((13C/12C and 15N/14N) were determined by continuous-flow isotope-ratio mass spectrometry in order to assess their potential as tracers for industrial emissions. Preliminary results showed high to very high average contents of several metals in the biomonitor compared to values from similar studies in other world regions, indicating a high degree of local air pollution. In contrast, most samples had Ag, As, Be, Se and Tl contents below detection levels (DL = 0.05 mg/kg of sample dry weight) indicating low levels of pollution by these metals. Metals such as Al, Ba, Ca, Fe, Li, Mo, Ni, Sr, Ti, V and Zn concentrated the most at the South portion of the valley, where the Tepeji-Tula-Apaxco industrial corridor is located. A transect parallel to the along-wind direction (N-S) showed a higher concentration of metals farther away from the sources relative to a cross-wind transect, which is consistent with the eolian transport of metal-enriched particles. Regional distribution maps of metals in the biomonitor showed that Al, Ba, Fe, Mo, Ni, Sr, Ti and V had higher levels at the industrial sampling sites; whereas K, Na and P were more abundant near to agriculture areas. Vanadium, a common element of crude oil, reflected better the influence from
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Hydrogeology of a drift-filled bedrock valley near Lino Lakes, Anoka County, Minnesota
Winter, T.C.; Pfannkuch, H.O.
1976-01-01
The bedrock surface of east-central Minnesota is dissected by an intricate network of valleys. Outside the bedrock valley at site B, 3 mi (4. 8 km) from site A, 100 ft (30 m) of drift overlies the bedrock surface. Observation wells were installed at the two sites to determine the vertical ground-water movement between the various aquifer units and the lateral movement between the two sites. An aquifer test of the lowest valley-fill aquifer at site A showed that the observation well completed in the same aquifer as the pumping well responded immediately; whereas a lag of about 100 min occurred between the lower valley fill and uppermost body of sand and gravel. This indicates that the hydraulic connection between these two layers is poor at the immediate site. Test results show that the lower sand-and-gravel aquifer has a transmissivity between 14,000 and 27,000 ft2/d (1,300 and 2,500 m2/d). Although the hydraulic gradient is vertically downward in the valley, much of the drift fill is poorly permeable. This suggests that the quantity of downward-percolating water reaching the lowest valley-fill aquifer is relatively small at the test site. Because valley cut through a number of bedrock aquifers in the region, they could potentially be an important avenue of contamination from land-surface waste. In addition, the vast network of bedrock valleys in the Twin Cities area might cause contaminants to disseminate rather rapidly throughout a large area.
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Truini, Margot; Beard, L. Sue; Kennedy, Jeffrey; Anning, Dave W.
2013-01-01
We have investigated the hydrogeology of the Hualapai Valley, Detrital Valley, and Sacramento Valley basins of Mohave County in northwestern Arizona to develop a better understanding of groundwater storage within the basin fill aquifers. In our investigation we used geologic maps, well-log data, and geophysical surveys to delineate the sedimentary textures and lithology of the basin fill. We used gravity data to construct a basin geometry model that defines smaller subbasins within the larger basins, and airborne transient-electromagnetic modeled results along with well-log lithology data to infer the subsurface distribution of basin fill within the subbasins. Hydrogeologic units (HGUs) are delineated within the subbasins on the basis of the inferred lithology of saturated basin fill. We used the extent and size of HGUs to estimate groundwater storage to depths of 400 meters (m) below land surface (bls). The basin geometry model for the Hualapai Valley basin consists of three subbasins: the Kingman, Hualapai, and southern Gregg subbasins. In the Kingman subbasin, which is estimated to be 1,200 m deep, saturated basin fill consists of a mixture of fine- to coarse-grained sedimentary deposits. The Hualapai subbasin, which is the largest of the subbasins, contains a thick halite body from about 400 m to about 4,300 m bls. Saturated basin fill overlying the salt body consists predominately of fine-grained older playa deposits. In the southern Gregg subbasin, which is estimated to be 1,400 m deep, saturated basin fill is interpreted to consist primarily of fine- to coarse-grained sedimentary deposits. Groundwater storage to 400 m bls in the Hualapai Valley basin is estimated to be 14.1 cubic kilometers (km3). The basin geometry model for the Detrital Valley basin consists of three subbasins: northern Detrital, central Detrital, and southern Detrital subbasins. The northern and central Detrital subbasins are characterized by a predominance of playa evaporite and fine
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NASA Astrophysics Data System (ADS)
Swanger, K. M.; Schaefer, J. M.; Winckler, G.; Lamp, J. L.; Marchant, D. R.
2016-12-01
Based on surface exposure dating of moraines and drifts, East Antarctic outlet glaciers in the McMurdo Dry Valleys (MDV) advanced during the mid-Pliocene and/or early-Pleistocene. However, scatter in exposure ages is common for these deposits (and other glacial drifts throughout Antarctica), making it difficult to tie glacial advances to specific climate intervals. In order to constrain the sources of scatter, we mapped and dated 15 cold-based drifts in Taylor Valley and the Olympus Range in the MDV. A secondary goal was to build a regional climate record, for comparison with fluctuations of the local outlet glaciers. Our alpine drift record is confined to the late-Pleistocene, with glacial advances during interglacial periods. Based on 54 3He exposure dates on alpine drifts, age scatter is common in the MDV on both recent and ancient deposits. Where it occurs, age scatter is likely caused by inheritance of cosmogenic nuclides previous to glacial entrainment and stacking of multiple cold-based drifts. Nuclide inheritance of >1 Myr is possible, but this is relatively rare and confined to regions where englacial debris is sourced from stable, high-elevation plateaus. On the other hand, drifts associated with glaciers bound by steep cirque headwalls and arêtes exhibit significantly less age scatter. Given the cold-based nature of MDV alpine and outlet glaciers, deposition of multiple stacked drift sheets also contributes to age scatter, with the implication that it might be possible to date multiple advances of cold-based ice. These results serve to inform better sampling strategies on cold-based drifts throughout Antarctica.
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Merging seismic and MT in Garden Valley, Nevada
DOE Office of Scientific and Technical Information (OSTI.GOV)
Telleen, K.E.
1986-04-01
In the northern part of Garden Valley, Nevada, a 1978 regional seismic program encountered a large area of poor to no-reflection data. Surface geology suggested that a large high structure might underlie the valley floor, and that shallowly buried basalts were causing the poor data. The implied strongly layered structure of electrical resistivity - resistive basalt on conductive Tertiary clastics on resistive paleozoic carbonates - formed an ideal theater for the magnetotelluric method. In 1984, Conoco acquired 48 magnetotelluric sites on about a half-mile grid. These data supported the presence of a buried high block in the Paleozoic rocks andmore » allowed confident mapping of its outlines. In addition, the magnetotelluric survey showed a thin, shallowly buried resistor coextensive with the seismic no-reflection area. In 1985, a high-effort repeat of the earlier no-reflection seismic line confirmed the high block, improved the fault interpretation, and provided weak guidance on the depth of the targeted Paleozoic rocks. Because Garden Valley's Paleozoic stratigraphy differs negligibly from that at nearby Grant Canyon field, the high block constitutes an attractive prospect - possibly the first one found in Nevada due largely to magnetotelluric surveying.« less
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A Crustal Velocity Model for South Mexicali Valley, Baja California, México.
NASA Astrophysics Data System (ADS)
Ramirez, E.; Vidal-Villegas, A.; Stock, J. M.; Gonzalez-Fernandez, A.
2016-12-01
The northern Baja California region consists of two subregions of different geological features: the Peninsular Ranges of Baja California, of granitic composition, and the Mexicali Valley region, characterized by a series of sedimentary basins: the Laguna Salada and the Mexicali Valley. Due to the lack of an appropriate crust model for South Mexicali Valley, a refraction study was conducted. We installed 16 three-component short period stations (2 Hz) and one broadband station (100 s - 50 Hz). The stations, spaced 6 km along a refraction profile, recorded a blast performed in the southwest Arizona near the border with Sonora, Mexico. Records gathered were used to estimate a crust velocity structure model for South Mexicali Valley. The beginning of the profile is at San Luis Rio Colorado (SLRC), Sonora and its ending is at the middle of Sierra Juarez, Baja California. As a "reverse shot", for a 47 km section between SLRC and El Mayor Mountain, we used an aftershock M 3.4 of the 2010 M 7.2 El Mayor - Cucapah earthquake. Record sections show seismograms with impulsive P arrivals for nearby stations. The arrival Pn wave is observed at three stations located in Laguna Salada and Sierra Juarez. From the first arrivals of refractions and reflections of the P wave we performed direct modeling of travel times and relative amplitudes (normalized synthetic seismograms). Method based on asymptotic ray theory programed in the RAYINVR software (Zelt and Smith, 1992). We propose an average-three-layer velocity structure model: 2.9, 5.6 and 6.9 km/s, with thicknesses of 1.2, 4.4 and 9.6 km, respectively. Velocities of our model for the region under study are about 1 km/s higher than the model proposed by McMechan and Mooney (1984) for the Imperial Valley. The preliminary interpretation using the "reverse shot" indicates a crust of 15 km depth beneath the Mexicali Valley and 19 km under the El Mayor Mountain and Laguna Salada basin. On the eastern side of the El Mayor Mountain we
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NASA Astrophysics Data System (ADS)
Belitz, Kenneth; Phillips, Steven P.
1995-08-01
The occurrence of selenium in agricultural drainage water derived from the central part of the western San Joaquin Valley has focused concern on alternatives to agricultural drains for managing shallow, poor-quality groundwater. A transient, three-dimensional simulation model was developed to evaluate the response of the water table to alternatives that affect recharge to or discharge from the groundwater flow system. The modeled area is 551 mi2 (1 mi2 = 2.59 km2) and includes both the semiconfined and confined zones above and below the Corcoran Clay Member of the Tulare Formation of Pleistocene age. The simulation model was calibrated using hydrologic data from 1972 to 1988, and was extended to the year 2040 to forecast for various management alternatives, including maintenance of present practices, land retirement, reduced recharge, increased groundwater pumping, and combinations of these alternatives. Maintenance of present practices results in a worsening of the situation: the total area subject to bare-soil evaporation increases from 224 mi2 in 1990 to 344 mi2 in 2040, and drain flow increases from 25,000 ac ft/yr (1 ac ft = 1234 m3) to 28,000 ac ft/yr. Although land retirement results in elimination of bare-soil evaporation and drain flow in the areas retired, it has little to no effect in adjacent areas. In contrast, regional-scale changes in recharge and pumping are effective for regional management. The area subject to bare-soil evaporation can be reduced to 78 mi2, and drain flow to 8000 ac ft/yr if (1) recharge is reduced by 15% (26,000 ac ft/yr) in areas that currently use surface and groundwater (362 mi2); (2) recharge is reduced by 40% (28,000 ac ft/yr) in areas that currently use only surface water (137 mi2); and (3) pumping rates are uniformly incremented by 0.5 ft/yr (160,000 ac ft/yr) in both areas. If these water budget changes were to be implemented in the study area, and in adjacent areas with similiar Hydrogeologic characteristics, then
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NASA Astrophysics Data System (ADS)
Moser, D. P.; Hamilton-Brehm, S.; Zhang, G.; Fisher, J.; Hughes, K.; Wheatley, A.; Thomas, J.; Zavarin, M.; Roberts, S. K.; Kryder, L.; McRae, R.; Howard, W.; Walker, J.; Federwisch, R.; King, M.; Friese, R.; Grim, S.; Amend, J.; Momper, L.; Sherwood Lollar, B.; Onstott, T. C.
2013-12-01
Recent decades have revealed anaerobic microbial ecosystems across a range of deep, continental settings; however, aerobic, regional aquifers represent a little-studied habitat for deep life. The US' Basin and Range Province is an extensional zone defined by deep, interconnected fracture systems that span multiple hydrologic basins and host regional aquifers. Here we describe a multi-basin microbiological assessment, applied to the Death Valley Regional Flow System (DVRFS). Our group has surveyed more than thirty deep boreholes (~ 1,000 m depth average) and deeply-sourced springs across a ~170 km inferred flow path from recharge areas in volcanic and carbonate rock highlands of the Nevada National Security Site (NNSS) and the Spring Mountains to discharge zones in Oasis, Amargosa, and Death Valleys. DVRFS waters were characterized by temperatures of 30 - 50 oC and the presence of dissolved O2 (4 - 8 mg/L in the recharge areas and ~0.2 - 2 mg/L in the discharge zones). Planktonic microbial populations, as tracked by molecular DNA approaches (e.g. 454 pyrotag), were of low abundance (e.g. ~ 10e3 ~10e6 per mL) and dominated by Proteobacteria and Nitrospirae. Archaea were also present and dominated by novel Thaumarchaeotes. Patterns of microbial diversity and the hypothesis that these patterns may have utility for recognition of hydrologic connectivity were assessed by statistical tools. At the species level, cosmopolitan, system-wide, and flow-path-specific groupings of both bacteria and archaea were detected. Even when in close proximity to aerobic springs and wells, sites sampling deep, hot, anaerobic groundwaters possessed completely distinct microbial populations (e.g. dominance by Firmicutes, ANME, and predicted methanogens). Among methodological refinements developed from this work, the repeated sampling of one deep borehole over a month-long pump test revealed that well-bore-associated contaminants required several days of pumping for complete removal and
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Landform Evolution of the Zanskar Valley, Ladakh Himalaya.
NASA Astrophysics Data System (ADS)
Chahal, P.; Kumar, A.; Sharma, P.; Sundriyal, Y.; Srivastava, P.
2017-12-01
Zanskar River flow from south-west to north-east, perpendicularly through Higher Himalayan crystalline sequences, Tethyan sedimentary sequences, and Indus Molasses; and finally merge with the Indus River at Nimu. Geologically, the Indus valley is bounded by Ladakh Batholith in the north and highly folded and thrusted Zanskar mountain ranges in the south. Sedimentary sequences of Zanskar ranges are largely of continental origin, which were uplifted and deformed via several north verging thrusts, where Zanskar counter thrust, Choksti and Indus-Bazgo thrusts are important thrust zone, and there is atleast 36 km of crustal shortening in the Zanskar section which continued from middle Miocene to the late Pleistocene. This shortening is accommodated mainly by north or north-east directed Zanskar backthrusts. Two major tributaries of Zanskar: Tsrapchu and Doda, flow in the headwaters, along the strike of South Tibetan Detachment System (STDs), an east-west trending regional fault. The present study incorporate field sedimentology, geomorphology and chronology of landform associated with Zanskar valley. In the upper Zanskar, alluvial fan, valley fill and strath terraces configured the major landforms with paleo-lake deposits in the area between the fans. The lower catchment, at the confluence of Zanskar and Indus rivers, exhibit mainly valley fill terraces and strath terraces. Chronology suggests diachronous aggradation in the upper and lower Zanskar catchments. In the upper Zanskar large scale valley aggradation took place with simultaneously fan progradation and flooding events from 45-15 ka. Luminescence chronology of the lower Zanskar indicates aggradation from 145-55 ka and 18-12 ka. The two aggradation basins are separated by a deep V-shaped gorge which is approximately 60 km long. The longitudinal profile of the Zanskar River shows several local convexities marking knick point zone, which suggests tectonically controlled topography.
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Bedrock mapping of buried valley networks using seismic reflection and airborne electromagnetic data
NASA Astrophysics Data System (ADS)
Oldenborger, G. A.; Logan, C. E.; Hinton, M. J.; Pugin, A. J.-M.; Sapia, V.; Sharpe, D. R.; Russell, H. A. J.
2016-05-01
In glaciated terrain, buried valleys often host aquifers that are significant groundwater resources. However, given the range of scales, spatial complexity and depth of burial, buried valleys often remain undetected or insufficiently mapped. Accurate and thorough mapping of bedrock topography is a crucial step in detecting and delineating buried valleys and understanding formative valley processes. We develop a bedrock mapping procedure supported by the combination of seismic reflection data and helicopter time-domain electromagnetic data with water well records for the Spiritwood buried valley aquifer system in Manitoba, Canada. The limited spatial density of water well bedrock observations precludes complete depiction of the buried valley bedrock topography and renders the water well records alone inadequate for accurate hydrogeological model building. Instead, we leverage the complementary strengths of seismic reflection and airborne electromagnetic data for accurate local detection of the sediment-bedrock interface and for spatially extensive coverage, respectively. Seismic reflection data are used to define buried valley morphology in cross-section beneath survey lines distributed over a regional area. A 3D model of electrical conductivity is derived from inversion of the airborne electromagnetic data and used to extrapolate buried valley morphology over the entire survey area. A spatially variable assignment of the electrical conductivity at the bedrock surface is applied to different features of the buried valley morphology identified in the seismic cross-sections. Electrical conductivity is then used to guide construction of buried valley shapes between seismic sections. The 3D locus of points defining each morphological valley feature is constructed using a path optimization routine that utilizes deviation from the assigned electrical conductivities as the cost function. Our resulting map represents a bedrock surface of unprecedented detail with more
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Utilization potential evaluation of plant resources in the dry-hot valley of Jinsha River
NASA Astrophysics Data System (ADS)
Xi, Rong; Xu, Naizhong; Liu, Shengxiang; Ren, Tingyan
2017-08-01
Plant resources in the dry-hot valley of Jinsha River are endemic to a class of district. The article adopts the analytic hierarchy process method to evaluate the exploitation and utilization potential of plant resources of thirty typical plant resources on the basis of their characteristics in the dry-hot valley of Jinsha River, which provide scientific evidence for quantitative evaluation of regional plant resources, and we also suggest pathways offering protection and development.
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Space Radar Image of Karakax Valley, China 3-D
1999-04-15
This three-dimensional perspective of the remote Karakax Valley in the northern Tibetan Plateau of western China was created by combining two spaceborne radar images using a technique known as interferometry. Visualizations like this are helpful to scientists because they reveal where the slopes of the valley are cut by erosion, as well as the accumulations of gravel deposits at the base of the mountains. These gravel deposits, called alluvial fans, are a common landform in desert regions that scientists are mapping in order to learn more about Earth's past climate changes. Higher up the valley side is a clear break in the slope, running straight, just below the ridge line. This is the trace of the Altyn Tagh fault, which is much longer than California's San Andreas fault. Geophysicists are studying this fault for clues it may be able to give them about large faults. Elevations range from 4000 m (13,100 ft) in the valley to over 6000 m (19,700 ft) at the peaks of the glaciated Kun Lun mountains running from the front right towards the back. Scale varies in this perspective view, but the area is about 20 km (12 miles) wide in the middle of the image, and there is no vertical exaggeration. http://photojournal.jpl.nasa.gov/catalog/PIA01800
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2001-10-22
These band composites, acquired on June 4, 2000, cover a 11 by 13.5 km sub-scene in the Coachella Valley, CA. The area is shown by the yellow box on the full scene in the LOWER RIGHT corner, northwest of the Salton Sea. This is a major agricultural region of California, growing fruit and produce throughout the year. Different combinations of ASTER bands help identify the different crop types. UPPER LEFT: bands 3, 2, 1 as red, green, and blue (RGB); UPPER RIGHT: bands 4, 2, 1 as RGB; LOWER LEFT: bands 4, 3, 2 as RGB. The image is centered at 33.6 degrees north latitude, 116.1 degrees west longitude. http://photojournal.jpl.nasa.gov/catalog/PIA11161
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Environmental Degradation in a Dependent Region: The Rio Grande Valley of Mexico and Texas.
ERIC Educational Resources Information Center
Jones, Richard C.
1999-01-01
Traces the interrelationships among dependence, environmental degradation, and human health in the Rio Grande Valley of Mexico and Texas. Presents a case study on environmental factors threatening family health in households located on both sides of the border; the health problems can be overcome by addressing restrictive zoning, health services,…
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Water availability and land subsidence in the Central Valley, California, USA
NASA Astrophysics Data System (ADS)
Faunt, Claudia C.; Sneed, Michelle; Traum, Jon; Brandt, Justin T.
2016-05-01
The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007-2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.
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Miller, David M.; Valin, Zenon C.
2007-01-01
This publication describes results from new regional and detailed surficial geologic mapping, combined with geomorphologic, geochronologic, and tectonic studies, in Silurian Valley and Death Valley, California. The studies address a long-standing problem, the tectonic and geomorphic evolution of the intersection between three regional tectonic provinces: the eastern California shear zone, the Basin and Range region of southern Nevada and adjacent California, and the eastern Mojave Desert region. The chapters represent work presented on the 2005 Friends of the Pleistocene field trip and meeting as well as the field trip road log.
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Pearthree, Philip; House, P. Kyle
2014-01-01
Geologic investigations of late Miocene–early Pliocene deposits in Mohave and Cottonwood valleys provide important insights into the early evolution of the lower Colorado River system. In the latest Miocene these valleys were separate depocenters; the floor of Cottonwood Valley was ∼200 m higher than the floor of Mohave Valley. When Colorado River water arrived from the north after 5.6 Ma, a shallow lake in Cottonwood Valley spilled into Mohave Valley, and the river then filled both valleys to ∼560 m above sea level (asl) and overtopped the bedrock divide at the southern end of Mohave Valley. Sediment-starved water spilling to the south gradually eroded the outlet as siliciclastic Bouse deposits filled the lake upstream. When sediment accumulation reached the elevation of the lowering outlet, continued erosion of the outlet resulted in recycling of stored lacustrine sediment into downstream basins; depth of erosion of the outlet and upstream basins was limited by the water levels in downstream basins. The water level in the southern Bouse basin was ∼300 m asl (modern elevation) at 4.8 Ma. It must have drained and been eroded to a level <150 m asl soon after that to allow for deep erosion of bedrock divides and basins upstream, leading to removal of large volumes of Bouse sediment prior to massive early Pliocene Colorado River aggradation. Abrupt lowering of regional base level due to spilling of a southern Bouse lake to the Gulf of California could have driven observed upstream river incision without uplift. Rapid uplift of the entire region immediately after 4.8 Ma would have been required to drive upstream incision if the southern Bouse was an estuary.
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-22
... Railway, LLC--Acquisition and Operation Exemption--Conecuh Valley Railroad Co., Inc. Conecuh Valley Railway, LLC (CVR), a noncarrier, has filed a verified notice of exemption under 49 CFR 1150.31 to acquire from Conecuh Valley Railroad Co., Inc. (COEH), and to operate [[Page 22747
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Diurnal cycle of air pollution in the Kathmandu Valley, Nepal: 2. Modeling results
NASA Astrophysics Data System (ADS)
Panday, Arnico K.; Prinn, Ronald G.; SchäR, Christoph
2009-11-01
After completing a 9-month field experiment studying air pollution and meteorology in the Kathmandu Valley, Nepal, we set up the mesoscale meteorological model MM5 to simulate the Kathmandu Valley's meteorology with a horizontal resolution of up to 1 km. After testing the model against available data, we used it to address specific questions to understand the factors that control the observed diurnal cycle of air pollution in this urban basin in the Himalayas. We studied the dynamics of the basin's nocturnal cold air pool, its dissipation in the morning, and the subsequent growth and decay of the mixed layer over the valley. During mornings, we found behavior common to large basins, with upslope flows and basin-center subsidence removing the nocturnal cold air pool. During afternoons the circulation in the Kathmandu Valley exhibited patterns common to plateaus, with cooler denser air originating over lower regions west of Kathmandu arriving through mountain passes and spreading across the basin floor, thereby reducing the mixed layer depth. We also examined the pathways of pollutant ventilation out of the valley. The bulk of the pollution ventilation takes place during the afternoon, when strong westerly winds blow in through the western passes of the valley, and the pollutants are rapidly carried out through passes on the east and south sides of the valley. In the evening, pollutants first accumulate near the surface, but then are lifted slightly when katabatic flows converge underneath. The elevated polluted layers are mixed back down in the morning, contributing to the morning pollution peak. Later in the morning a fraction of the valley's pollutants travels up the slopes of the valley rim mountains before the westerly winds begin.
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Koo, Hyunmin; Strope, Bailey M; Kim, Eddy H; Shabani, Adel M; Kumar, Ranjit; Crowley, Michael R; Andersen, Dale T; Bej, Asim K
2016-01-21
Janthinobacterium sp. Ant5-2-1, isolated from the Schirmacher Oasis of East Antarctica, produces a purple-violet pigment, manifests diverse energy metabolism abilities, and tolerates cold, ultraviolet radiation, and other environmental stressors. We report here the 6.19-Mb draft genome of strain Ant5-2-1, which will help understand its survival mechanisms in extreme Antarctic ecosystems. Copyright © 2016 Koo et al.
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Magmatic Intrusions and a Hydrothermal Origin for Fluvial Valleys on Mars
NASA Technical Reports Server (NTRS)
Gulick, Virginia C
1998-01-01
Numerical models of Martian hydrothermal systems demonstrate that systems associated with magmatic intrusions greater than several hundred cubic kilometers can provide sufficient groundwater outflow to form the observed fluvial valleys, if subsurface permeability exceeds about 1.0 darcy. Groundwater outflow increases with increasing intrusion volume and subsurface permeability and is relatively insensitive to intrusion depth and subsurface porosity within the range considered here. Hydrothermally-derived fluids can melt through 1 to 2 km thick ice-rich permafrost layers in several thousand years. Hydrothermal systems thus provide a viable alternative to rainfall for providing surface water for valley formation. This mechanism can form fluvial valleys not only during the postulated early warm, wet climatic epoch, but also during more recent epochs when atmospheric conditions did not favor atmospheric cycling of water. The clustered distribution of the valley networks on a given geologic surface or terrain unit of Mars may also be more compatible with localized, hydrothermally-driven groundwater outflow than regional rainfall. Hydrothermal centers on Mars may have provided appropriate environments for the initiation of life or final oases for the long-term persistence of life.
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Modeling Events in the Lower Imperial Valley Basin
NASA Astrophysics Data System (ADS)
Tian, X.; Wei, S.; Zhan, Z.; Fielding, E. J.; Helmberger, D. V.
2010-12-01
The Imperial Valley below the US-Mexican border has few seismic stations but many significant earthquakes. Many of these events, such as the recent El Mayor-Cucapah event, have complex mechanisms involving a mixture of strike-slip and normal slip patterns with now over 30 aftershocks with magnitude over 4.5. Unfortunately, many earthquake records from the Southern Imperial Valley display a great deal of complexity, ie., strong Rayleigh wave multipathing and extended codas. In short, regional recordings in the US are too complex to easily separate source properties from complex propagation. Fortunately, the Dec 30 foreshock (Mw=5.9) has excellent recordings teleseismically and regionally, and moreover is observed with InSAR. We use this simple strike-slip event to calibrate paths. In particular, we are finding record segments involving Pnl (including depth phases) and some surface waves (mostly Love waves) that appear well behaved, ie., can be approximated by synthetics from 1D local models and events modeled with the Cut-and-Paste (CAP) routine. Simple events can then be identified along with path calibration. Modeling the more complicated paths can be started with known mechanisms. We will report on both the aftershocks and historic events.
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Grizzly Valley fault system, Sierra Valley, CA
Gold, Ryan; Stephenson, William; Odum, Jack; Briggs, Rich; Crone, Anthony; Angster, Steve
2012-01-01
The Grizzly Valley fault system (GVFS) strikes northwestward across Sierra Valley, California and is part of a network of active, dextral strike-slip faults in the northern Walker Lane (Figure 1). To investigate Quaternary motion across the GVFS, we analyzed high-resolution (0.25 m) airborne LiDAR data (Figure 2) in combination with six, high-resolution, P-wave, seismic-reflection profiles [Gold and others, 2012]. The 0.5- to 2.0-km-long seismic-reflection profiles were sited orthogonal to suspected tectonic lineaments identified from previous mapping and our analysis of airborne LiDAR data. To image the upper 400–700 m of subsurface stratigraphy of Sierra Valley (Figure 3), we used a 230-kg accelerated weight drop source. Geophone spacing ranged from 2 to 5 m and shots were co-located with the geophones. The profiles reveal a highly reflective, deformed basal marker that we interpret to be the top of Tertiary volcanic rocks, overlain by a 120- to 300-m-thick suite of subhorizontal reflectors we interpret as Plio-Pleistocene lacustrine deposits. Three profiles image the principle active trace of the GVFS, which is a steeply dipping fault zone that offsets the volcanic rocks and the basin fill (Figures 4 & 5).
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Topological Valley Currents in Gapped Dirac Materials
NASA Astrophysics Data System (ADS)
Lensky, Yuri D.; Song, Justin C. W.; Samutpraphoot, Polnop; Levitov, Leonid S.
2015-06-01
Gapped 2D Dirac materials, in which inversion symmetry is broken by a gap-opening perturbation, feature a unique valley transport regime. Topological valley currents in such materials are dominated by bulk currents produced by electronic states just beneath the gap rather than by edge modes. The system ground state hosts dissipationless persistent valley currents existing even when topologically protected edge modes are absent. Valley currents induced by an external bias are characterized by a quantized half-integer valley Hall conductivity. The undergap currents dominate magnetization and the charge Hall effect in a light-induced valley-polarized state.
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1981-08-01
valleys are typical of the Basin and Range Province, characterized by parallel, north-south trending mountain ranges, separated by hydrologically closed... basins . Pine and Wah Wah valleys each have hardpan-playas in their lowest areas. State Highway 21 runs roughly northwest-southeast through both val...have been important for prehis- toric and historic use of the area. Pine Valley: Pine and Wah Wah valleys are closed alluvial basins . The central part
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Space Radar Image of Wadi Kufra, Libya
1998-04-14
The ability of a sophisticated radar instrument to image large regions of the world from space, using different frequencies that can penetrate dry sand cover, produced the discovery in this image: a previously unknown branch of an ancient river, buried under thousands of years of windblown sand in a region of the Sahara Desert in North Africa. This area is near the Kufra Oasis in southeast Libya, centered at 23.3 degrees north latitude, 22.9 degrees east longitude. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar when it flew aboard the space shuttle Endeavour on its 60th orbit on October 4, 1994. This SIR-C image reveals a system of old, now inactive stream valleys, called "paleodrainage systems, http://photojournal.jpl.nasa.gov/catalog/PIA01310
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1993-06-01
This decision document presents the selected remedial action for the Glendale North Operable Unit, San Fernando Valley Area 2 Superfund site. The remedy involves groundwater extraction and treatment for the shallow aquifer system in the Glendale area of the San Fernando Valley.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1993-06-01
This decision document presents the selected remedial action for the Glendale South Operable Unit, San Fernando Valley Area 2 Superfund site. The remedy involves groundwater extraction and treatment for the shallow aquifer system in the Glendale area of the San Fernando Valley.
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Localized and Areally Extensive Alterations in Marathon Valley, Endeavour Crater Rim, Mars
NASA Technical Reports Server (NTRS)
Mittlefehldt, David W.; Gellert, Ralf; Van Bommel, Scott; Arvidson, Raymond E.; Clark, Benton C.; Cohen, Barbara A.; Farrand, William H.; Ming, Douglas W.; Schroeder, Christian; Yen, Albert S.;
2016-01-01
Mars Exploration Rover Opportunity is exploring the rim of 22 km diameter, Noachian-aged Endeavour crater. Marathon Valley cuts through the central region of the western rim providing a window into the local lower rim stratigraphic record. Spectra from the Compact Reconnaissance Imaging Spectrometer for Mars show evidence for the occurrence of Fe-Mg smectite in this valley, indicating areally extensive and distinct lithologic units and/or styles of aqueous alteration. The Alpha Particle X-ray Spectrometer has determined the compositions of 59 outcrop targets on untreated, brushed and abraded surfaces. Rocks in the Marathon Valley region are soft breccias composed of mm- to cm-sized darker clasts set in a lighter-toned, finegrained matrix. They are basaltic in non-volatile-element composition and compositionally similar to breccias investigated elsewhere on the rim. Alteration styles recorded in the rocks include: (1) Enrichments in Si, Al, Ti and Cr in more reddish-colored rock, consistent with leaching of more soluble cations and/or precipitation of Si +/- Al, Ti, Cr from fluids. Coprecipitation of Ge-rich phases with Si occurred in the western area only; high water:rock is indicated. Pancam multispectral observations indicate higher nanophase ferric oxide contents, but the rocks have lower Fe contents. The highly localized nature of the red zones indicate they cannot be the source of the widespread smectite signature observed from orbit. (2) Outcrops separated by approximately 65 m show common compositional changes between brushed and abraded (approximately 1 mm deep) targets: increases in S and Mg; decreases in Al, Cl and Ca. These changes are likely due to relatively recent, surface-related alteration of valley rocks and formation of surface coatings under low water:rock. (3) One target, from the center of a region of strong CRISM smectite signature, shows modest differences in composition (higher Si, K; lower Mn) compared to most Marathon Valley rocks, while
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Increased body mass of ducks wintering in California's Central Valley
Fleskes, Joseph P.; Yee, Julie L.; Yarris, Gregory S.; Loughman, Daniel L.
2016-01-01
Waterfowl managers lack the information needed to fully evaluate the biological effects of their habitat conservation programs. We studied body condition of dabbling ducks shot by hunters at public hunting areas throughout the Central Valley of California during 2006–2008 compared with condition of ducks from 1979 to 1993. These time periods coincide with habitat increases due to Central Valley Joint Venture conservation programs and changing agricultural practices; we modeled to ascertain whether body condition differed among waterfowl during these periods. Three dataset comparisons indicate that dabbling duck body mass was greater in 2006–2008 than earlier years and the increase was greater in the Sacramento Valley and Suisun Marsh than in the San Joaquin Valley, differed among species (mallard [Anas platyrhynchos], northern pintail [Anas acuta], America wigeon [Anas americana], green-winged teal [Anas crecca], and northern shoveler [Anas clypeata]), and was greater in ducks harvested late in the season. Change in body mass also varied by age–sex cohort and month for all 5 species and by September–January rainfall for all except green-winged teal. The random effect of year nested in period, and sometimes interacting with other factors, improved models in many cases. Results indicate that improved habitat conditions in the Central Valley have resulted in increased winter body mass of dabbling ducks, especially those that feed primarily on seeds, and this increase was greater in regions where area of post-harvest flooding of rice and other crops, and wetland area, has increased. Conservation programs that continue to promote post-harvest flooding and other agricultural practices that benefit wintering waterfowl and continue to restore and conserve wetlands would likely help maintain body condition of wintering dabbling ducks in the Central Valley of California.
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Susan D. Olberding; Karen Malis-Clark; Peter J. Pilles; Dennis Lund
2008-01-01
This poster presents the continuing cooperative relationship between the Fort Valley Experimental Forest (FVEF), Coconino National Forest (CNF), USFS Region 3, and the long-term partnerships with the Museum of the Northern Arizona and the NAU School of Forestry. Fort Valley was initially named the Coconino Experiment Station and funds were channeled...
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Paper birch: Sentinels of climate change in the Niobrara River Valley, Nebraska
Stroh, Esther D.
2011-01-01
The Niobrara River Valley in the northern Great Plains supports scattered stands of paper birch (Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation. Localized summer microclimates have likely facilitated the persistence of birch populations in a region otherwise unsuitable for the species. Dieback of canopy-sized birch has been observed throughout the valley in recent years, although no onset dates are documented. Changes in spring weather patterns may be causing rootlet injury so that trees die in spite of the still-cool summer microclimates. Current weather patterns, combined with little evidence of recruitment of young birch and great geographic distances from potential immigrant sources, make the future persistence of birch in the Niobrara River Valley stands uncertain.
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David E. Nagel; John M. Buffington; Sharon L. Parkes; Seth Wenger; Jaime R. Goode
2014-01-01
Valley confinement is an important landscape characteristic linked to aquatic habitat, riparian diversity, and geomorphic processes. This report describes a GIS program called the Valley Confinement Algorithm (VCA), which identifies unconfined valleys in montane landscapes. The algorithm uses nationally available digital elevation models (DEMs) at 10-30 m resolution to...
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Graphene Nanobubbles as Valley Filters and Beam Splitters
NASA Astrophysics Data System (ADS)
Settnes, Mikkel; Power, Stephen R.; Brandbyge, Mads; Jauho, Antti-Pekka
2016-12-01
The energy band structure of graphene has two inequivalent valleys at the K and K' points of the Brillouin zone. The possibility to manipulate this valley degree of freedom defines the field of valleytronics, the valley analogue of spintronics. A key requirement for valleytronic devices is the ability to break the valley degeneracy by filtering and spatially splitting valleys to generate valley polarized currents. Here, we suggest a way to obtain valley polarization using strain-induced inhomogeneous pseudomagnetic fields (PMFs) that act oppositely on the two valleys. Notably, the suggested method does not involve external magnetic fields, or magnetic materials, unlike previous proposals. In our proposal the strain is due to experimentally feasible nanobubbles, whose associated PMFs lead to different real space trajectories for K and K' electrons, thus allowing the two valleys to be addressed individually. In this way, graphene nanobubbles can be exploited in both valley filtering and valley splitting devices, and our simulations reveal that a number of different functionalities are possible depending on the deformation field.
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Geophysical framework of the northern San Francisco Bay region, California
Langenheim, Victoria; Graymer, Russell W.; Jachens, Robert C.; McLaughlin, Robert J.; Wagner, D.L.; Sweetkind, Donald
2010-01-01
We use geophysical data to examine the structural framework of the northern San Francisco Bay region, an area that hosts the northward continuation of the East Bay fault system. Although this fault system has accommodated ∼175 km of right-lateral offset since 12 Ma, how this offset is partitioned north of the bay is controversial and important for understanding where and how strain is accommodated along this stretch of the broader San Andreas transform margin. Using gravity and magnetic data, we map these faults, many of which influenced basin formation and volcanism. Continuity of magnetic anomalies in certain areas, such as Napa and Sonoma Valleys, the region north of Napa Valley, and the region south of the Santa Rosa Plain, preclude significant (>10 km) offset. Much of the slip is partitioned around Sonoma and Napa Valleys and onto the Carneros, Rodgers Creek, and Green Valley faults. The absence of correlative magnetic anomalies across the Hayward–Rodgers Creek–Maacama fault system suggests that this system reactivated older basement structures, which appear to influence seismicity patterns in the region.
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Mapping Ecosystem Services in the Jordan Valley, Jordan
NASA Astrophysics Data System (ADS)
Luz, Ana; Marques, Ana; Ribeiro, Inês; Alho, Maria; Catarina Afonso, Ana; Almeida, Erika; Branquinho, Cristina; Talozi, Samer; Pinho, Pedro
2016-04-01
In the last decade researchers started using ecosystem services as a new framework to understand the relationships between environment and society. Habitat quality and water quality are related with ecosystem services regulation and maintenance, or even provision. According to the Common International Classification of Ecosystem Services (CICES) both habitat quality and water quality are associated with lifecycle maintenance, habitat and gene pool protection, and water conditions, among others. As there is increased pressure on habitats and rivers especially for agricultural development, mapping and evaluating habitat and water quality has important implications for resource management and conservation, as well as for rural development. Here, we model and map habitat and water quality in the Jordan Valley, Jordan. In this study, we aim to identify and analyse ecosystem services both through 1) habitat quality and 2) water quality modelling using InVest, an integrated valuation of ecosystem services and tradeoffs. The data used in this study mainly includes the LULC, Jordan River watershed and main threats and pollutants in the study area, such as agriculture, industry, fish farms and urbanization. Results suggest a higher pressure on natural habitats in the Northern region of the Jordan Valley, where industry is dominant. Agriculture is present along the Jordan Valley and limits the few natural forested areas. Further, water pollution is mainly concentrated in disposal sites due to the low flow of the Jordan River. Our results can help to identify areas where natural resources and water resource management is most needed in the Jordan Valley. Acknowledgements: Transbasin FP7 project
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Glaciated valleys in Europe and western Asia
Prasicek, Günther; Otto, Jan-Christoph; Montgomery, David R.; Schrott, Lothar
2015-01-01
In recent years, remote sensing, morphometric analysis, and other computational concepts and tools have invigorated the field of geomorphological mapping. Automated interpretation of digital terrain data based on impartial rules holds substantial promise for large dataset processing and objective landscape classification. However, the geomorphological realm presents tremendous complexity and challenges in the translation of qualitative descriptions into geomorphometric semantics. Here, the simple, conventional distinction of V-shaped fluvial and U-shaped glacial valleys was analyzed quantitatively using multi-scale curvature and a novel morphometric variable termed Difference of Minimum Curvature (DMC). We used this automated terrain analysis approach to produce a raster map at a scale of 1:6,000,000 showing the distribution of glaciated valleys across Europe and western Asia. The data set has a cell size of 3 arc seconds and consists of more than 40 billion grid cells. Glaciated U-shaped valleys commonly associated with erosion by warm-based glaciers are abundant in the alpine regions of mid Europe and western Asia but also occur at the margins of mountain ice sheets in Scandinavia. The high-level correspondence with field mapping and the fully transferable semantics validate this approach for automated analysis of yet unexplored terrain around the globe and qualify for potential applications on other planetary bodies like Mars. PMID:27019665
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NASA Astrophysics Data System (ADS)
Jawak, Shridhar D.; Jadhav, Ajay; Luis, Alvarinho J.
2016-05-01
Supraglacial debris was mapped in the Schirmacher Oasis, east Antarctica, by using WorldView-2 (WV-2) high resolution optical remote sensing data consisting of 8-band calibrated Gram Schmidt (GS)-sharpened and atmospherically corrected WV-2 imagery. This study is a preliminary attempt to develop an object-oriented rule set to extract supraglacial debris for Antarctic region using 8-spectral band imagery. Supraglacial debris was manually digitized from the satellite imagery to generate the ground reference data. Several trials were performed using few existing traditional pixel-based classification techniques and color-texture based object-oriented classification methods to extract supraglacial debris over a small domain of the study area. Multi-level segmentation and attributes such as scale, shape, size, compactness along with spectral information from the data were used for developing the rule set. The quantitative analysis of error was carried out against the manually digitized reference data to test the practicability of our approach over the traditional pixel-based methods. Our results indicate that OBIA-based approach (overall accuracy: 93%) for extracting supraglacial debris performed better than all the traditional pixel-based methods (overall accuracy: 80-85%). The present attempt provides a comprehensive improved method for semiautomatic feature extraction in supraglacial environment and a new direction in the cryospheric research.
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Town of Chino Valley Municipal Water System Improvement Project FONSI and EA
EPA Region 9 has prepared an Environmental Assessment (EA) describing the potential environmental impacts associated with, and the alternatives to, the proposed Water System Improvement Project in the town of China Valley, Arizona. This Finding of No Signi
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D'Agnese, F. A.; Faunt, C.C.; Turner, A.K.; ,
1996-01-01
The recharge and discharge components of the Death Valley regional groundwater flow system were defined by techniques that integrated disparate data types to develop a spatially complex representation of near-surface hydrological processes. Image classification methods were applied to multispectral satellite data to produce a vegetation map. The vegetation map was combined with ancillary data in a GIS to delineate different types of wetlands, phreatophytes and wet playa areas. Existing evapotranspiration-rate estimates were used to calculate discharge volumes for these area. An empirical method of groundwater recharge estimation was modified to incorporate data describing soil-moisture conditions, and a recharge potential map was produced. These discharge and recharge maps were readily converted to data arrays for numerical modelling codes. Inverse parameter estimation techniques also used these data to evaluate the reliability and sensitivity of estimated values.The recharge and discharge components of the Death Valley regional groundwater flow system were defined by remote sensing and GIS techniques that integrated disparate data types to develop a spatially complex representation of near-surface hydrological processes. Image classification methods were applied to multispectral satellite data to produce a vegetation map. This map provided a basis for subsequent evapotranspiration and infiltration estimations. The vegetation map was combined with ancillary data in a GIS to delineate different types of wetlands, phreatophytes and wet playa areas. Existing evapotranspiration-rate estimates were then used to calculate discharge volumes for these areas. A previously used empirical method of groundwater recharge estimation was modified by GIS methods to incorporate data describing soil-moisture conditions, and a recharge potential map was produced. These discharge and recharge maps were readily converted to data arrays for numerical modelling codes. Inverse parameter
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NASA Astrophysics Data System (ADS)
Ansan, V.; Mangold, N.
2013-09-01
valley networks have been identified mainly in the Noachian heavily cratered uplands. Eight dense branching valley networks were studied in Noachian terrains of Huygens, Newcomb and Kepler craters, south Tyrrhena Terra, and Thaumasia, in Hesperian terrains of Echus Plateau and west Eberswalde craters, and in Amazonian terrains of Alba Patera, using images and digital elevation models from the Mars Express High Resolution Stereo Camera to determine 2D and 3D morphometric parameters. Extracted geomorphic parameters show similar geometry to terrestrial valleys: drainage densities, organization from bifurcation ratios and lengths ratios, Hack exponent consistent with terrestrial values of ~0.6, and progressive deepening of valleys with increasing Strahler order. In addition, statistics on valley depths indicate a deeper incision of Noachian valleys compared to younger post-Noachian valleys (<25 m for Amazonian ones compared to >100 m for Noachian ones), showing a strong difference in fluvial erosion. These characteristics show that dense Martian valley networks formed by overland flows in relation to a global atmospheric water cycle in Noachian epoch and confirm that the later stages of activity may be related to shorter duration of activity, distinct climatic conditions, and/or regional processes, or conditions.
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NASA Astrophysics Data System (ADS)
Ang, Yee Sin; Yang, Shengyuan A.; Zhang, C.; Ma, Zhongshui; Ang, L. K.
2017-12-01
Despite much anticipation of valleytronics as a candidate to replace the aging complementary metal-oxide-semiconductor (CMOS) based information processing, its progress is severely hindered by the lack of practical ways to manipulate valley polarization all electrically in an electrostatic setting. Here, we propose a class of all-electric-controlled valley filter, valve, and logic gate based on the valley-contrasting transport in a merging Dirac cones system. The central mechanism of these devices lies on the pseudospin-assisted quantum tunneling which effectively quenches the transport of one valley when its pseudospin configuration mismatches that of a gate-controlled scattering region. The valley polarization can be abruptly switched into different states and remains stable over semi-infinite gate-voltage windows. Colossal tunneling valley-pseudomagnetoresistance ratio of over 10 000 % can be achieved in a valley-valve setup. We further propose a valleytronic-based logic gate capable of covering all 16 types of two-input Boolean logics. Remarkably, the valley degree of freedom can be harnessed to resurrect logical reversibility in two-input universal Boolean gate. The (2 +1 ) polarization states (two distinct valleys plus a null polarization) reestablish one-to-one input-to-output mapping, a crucial requirement for logical reversibility, and significantly reduce the complexity of reversible circuits. Our results suggest that the synergy of valleytronics and digital logics may provide new paradigms for valleytronic-based information processing and reversible computing.
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Investigating Groundwater Depletion and Aquifer Degradation in Central Valley California from Space
NASA Astrophysics Data System (ADS)
Ojha, C.; Shirzaei, M.; Werth, S.; Argus, D. F.
2017-12-01
The Central Valley in California includes one of the world's largest and yet most stressed aquifer systems. The large demand for groundwater, accelerated by population growth and extreme droughts, has been depleting the region's groundwater resources for decades. However, the lack of dense monitoring networks and inaccurate information on geophysical aquifer response pose serious challenges to water management efforts in the area and put the groundwater at high risk. Here, we performed a joint analysis of large SAR interferometric data sets acquired by ALOS L-band satellite in conjunction with the groundwater level observations across the Central Valley. We used 420 L-band SAR images acquired on the ascending orbit track during period Dec 24, 2006 - Jan 1, 2010, and generated more than 1600 interferograms with a pixel size of 100 m × 100 m. We also use data from 1600 observational wells providing continuous measurements of groundwater level within the study period for our analysis. We find that in the south and near Tulare Lake, north of Tule and south of Kaweah basin in San Joaquin valley, the subsidence rate is greatest at up to 20-25 cm/yr, while in Sacramento Valley the subsidence rate is lower at 1-3 cm/yr. From the characterization of the elastic and inelastic storage coefficients, we find that Kern, Tule, Tulare, Kaweah and Merced basins in the San Joaquin Valley are more susceptible to permanent compaction and aquifer storage loss. Kern County shows 0.23%-1.8% of aquifer storage loss during the study period, and has higher percentage loss than adjacent basins such as Tule and Tulare Lake with 0.15%-1.2% and 0.2 %-1.5% loss, respectively. Overall, we estimate that the aquifers across the valley lost a total of 28 km3 of groundwater and 2% of their storage capacity during the study period. Our unique observational evidence including valley-wide estimate of mechanical properties of aquifers and model results will not only facilitate monitoring water deficits
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Water availability and land subsidence in the Central Valley, California, USA
Faunt, Claudia; Sneed, Michelle; Traum, Jonathan A.; Brandt, Justin
2016-01-01
The Central Valley in California (USA) covers about 52,000 km2 and is one of the most productive agricultural regions in the world. This agriculture relies heavily on surface-water diversions and groundwater pumpage to meet irrigation water demand. Because the valley is semi-arid and surface-water availability varies substantially, agriculture relies heavily on local groundwater. In the southern two thirds of the valley, the San Joaquin Valley, historic and recent groundwater pumpage has caused significant and extensive drawdowns, aquifer-system compaction and subsidence. During recent drought periods (2007–2009 and 2012-present), groundwater pumping has increased owing to a combination of decreased surface-water availability and land-use changes. Declining groundwater levels, approaching or surpassing historical low levels, have caused accelerated and renewed compaction and subsidence that likely is mostly permanent. The subsidence has caused operational, maintenance, and construction-design problems for water-delivery and flood-control canals in the San Joaquin Valley. Planning for the effects of continued subsidence in the area is important for water agencies. As land use, managed aquifer recharge, and surface-water availability continue to vary, long-term groundwater-level and subsidence monitoring and modelling are critical to understanding the dynamics of historical and continued groundwater use resulting in additional water-level and groundwater storage declines, and associated subsidence. Modeling tools such as the Central Valley Hydrologic Model, can be used in the evaluation of management strategies to mitigate adverse impacts due to subsidence while also optimizing water availability. This knowledge will be critical for successful implementation of recent legislation aimed toward sustainable groundwater use.
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27 CFR 9.78 - Ohio River Valley.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ohio River Valley. 9.78... River Valley. (a) Name. The name of the viticultural area described in this section is “Ohio River Valley.” (b) Approved maps. The approved maps for determining the boundary of the Ohio River Valley...
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Valley dependent transport in graphene L junction
NASA Astrophysics Data System (ADS)
Chan, K. S.
2018-05-01
We studied the valley dependent transport in graphene L junctions connecting an armchair lead and a zigzag lead. The junction can be used in valleytronic devices and circuits. Electrons injected from the armchair lead into the junction is not valley polarized, but they can become valley polarized in the zigzag lead. There are Fermi energies, where the current in the zigzag lead is highly valley polarized and the junction is an efficient generator of valley polarized current. The features of the valley polarized current depend sensitively on the widths of the two leads, as well as the number of dimers in the armchair lead, because this number has a sensitive effect on the band structure of the armchair lead. When an external potential is applied to the junction, the energy range with high valley polarization is enlarged enhancing its function as a generator of highly valley polarized current. The scaling behavior found in other graphene devices is also found in L junctions, which means that the results presented here can be extended to junctions with larger dimensions after appropriate scaling of the energy.
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NASA Astrophysics Data System (ADS)
Spötl, Christoph; Dublyansky, Yuri; Moseley, Gina; Wendt, Kathleen; Edwards, Larry; Scholger, Robert; Woodhead, Jon
2016-04-01
Death Valley in eastern California holds North Americás record for the deepest, hottest and driest place. Despite these unfavourable boundary conditions speleothems are present in this hyperarid depression and the surrounding deserts and provide unique insights into long-term regional climate change and landscape evolution of this tectonically and geomorphologically highly active region. Most of the speleothems are inactive and exposed due to tectonic uplift and erosion. They differ from common speleothems, because the majority formed under phreatic conditions as part of a regional groundwater flow system that is still active today. Data from three sites will be discussed illustrating the spectrum of speleothem deposits and their modes of formation. At Devils Hole, the thermal aquifer and the associated subaqueous and water-table speleothems can be directly accessed and provide a record reaching back about 1 million years. At Travertine Point, close to modern discharge points of this large groundwater flow system, phreatic speleothems form near-vertical veins up to about 2 m wide showing evidence of high flow rates along these fractures, which are connected to fossil spring tufa deposits. Finally, outcrops along Titus Canyon expose several generations of speleothems documenting the progressive lowering of the regional groundwater table. The youngest calcite generation records the transition towards vadose conditions 500-400 ka ago.
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NASA Astrophysics Data System (ADS)
Asfahani, Jamal
2016-05-01
A new alternative approach based on using Vertical electrical sounding (VES) technique is proposed for computing the hydraulic conductivity K of an aquifer. The approach takes only the salinity of the groundwater into consideration. VES measurements in the locations, where available water samples exist, are required in such an approach, in order to calibrate and establish empirical relationships between transverse resistance Dar-Zarrouck TR parameter and modified transverse resistance MTR, and between MTR and transmissivity T. Those relationships are thereafter used to extrapolate the transmissivity even in the VES points where no water samples exist. This approach is tested and practiced in the Khanasser valley, Northern Syria, where the hydraulic conductivity of the Quaternary aquifer is computed. An acceptable agreement is found between the hydraulic conductivity values obtained by the proposed approach and those obtained by the pumping test which range between 0.864 and 8.64 m/day (10-5 and 10-4 m/s). The Quaternary aquifer transmissivity of the Khanasser Valley, has been characterized by using this approach and by adapting the MTR parameter. The transmissivity varies between a minimum of 79 m2/day and a maximum of 814 m2/day, with an average of 283 m2/day and a standard deviation of 145 m2/day. The easy and inexpensive approach proposed in this paper can be applied in other semi arid regions.
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Valley-isospin dependence of the quantum Hall effect in a graphene p-n junction
NASA Astrophysics Data System (ADS)
Tworzydło, J.; Snyman, I.; Akhmerov, A. R.; Beenakker, C. W. J.
2007-07-01
We calculate the conductance G of a bipolar junction in a graphene nanoribbon, in the high-magnetic-field regime where the Hall conductance in the p -doped and n -doped regions is 2e2/h . In the absence of intervalley scattering, the result G=(e2/h)(1-cosΦ) depends only on the angle Φ between the valley isospins ( =Bloch vectors representing the spinor of the valley polarization) at the two opposite edges. This plateau in the conductance versus Fermi energy is insensitive to electrostatic disorder, while it is destabilized by the dispersionless edge state which may exist at a zigzag boundary. A strain-induced vector potential shifts the conductance plateau up or down by rotating the valley isospin.
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ERIC Educational Resources Information Center
Salter, Linda Graef
1999-01-01
Describes the partnerships formed by West Valley Mission Community College District (California) with its surrounding Silicon Valley business community in an effort to benefit workforce development. Asserts that community colleges are uniquely positioned to provide a lifelong education that will yield a skilled workforce to meet the needs of…
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2013-01-01
Rift Valley fever virus (Phlebovirus, Bunyaviridae) is an arbovirus causing intermittent epizootics and sporadic epidemics primarily in East Africa. Infection causes severe and often fatal illness in young sheep, goats and cattle. Domestic animals and humans can be contaminated by close contact with infectious tissues or through mosquito infectious bites. Rift Valley fever virus was historically restricted to sub-Saharan countries. The probability of Rift Valley fever emerging in virgin areas is likely to be increasing. Its geographical range has extended over the past years. As a recent example, autochthonous cases of Rift Valley fever were recorded in 2007–2008 in Mayotte in the Indian Ocean. It has been proposed that a single infected animal that enters a naive country is sufficient to initiate a major outbreak before Rift Valley fever virus would ever be detected. Unless vaccines are available and widely used to limit its expansion, Rift Valley fever will continue to be a critical issue for human and animal health in the region of the Indian Ocean. PMID:24016237
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Balenghien, Thomas; Cardinale, Eric; Chevalier, Véronique; Elissa, Nohal; Failloux, Anna-Bella; Jean Jose Nipomichene, Thiery Nirina; Nicolas, Gaelle; Rakotoharinome, Vincent Michel; Roger, Matthieu; Zumbo, Betty
2013-09-09
Rift Valley fever virus (Phlebovirus, Bunyaviridae) is an arbovirus causing intermittent epizootics and sporadic epidemics primarily in East Africa. Infection causes severe and often fatal illness in young sheep, goats and cattle. Domestic animals and humans can be contaminated by close contact with infectious tissues or through mosquito infectious bites. Rift Valley fever virus was historically restricted to sub-Saharan countries. The probability of Rift Valley fever emerging in virgin areas is likely to be increasing. Its geographical range has extended over the past years. As a recent example, autochthonous cases of Rift Valley fever were recorded in 2007-2008 in Mayotte in the Indian Ocean. It has been proposed that a single infected animal that enters a naive country is sufficient to initiate a major outbreak before Rift Valley fever virus would ever be detected. Unless vaccines are available and widely used to limit its expansion, Rift Valley fever will continue to be a critical issue for human and animal health in the region of the Indian Ocean.
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Hazardous Waste Cleanup: West Valley Demonstration Project USDOE in West Valley, New York
The U.S. Department of Energy's West Valley Demonstration Project is located at 10282 Rock Spring Road in West Valley, New York. This is a 167 acre, Department of Energy (DOE)-operated portion of a 3,300-acre site owned by the New York State Energy
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NASA Technical Reports Server (NTRS)
Patel, S. N.; Bishop, J. L.; Englert, P.; Gibson, E. K.
2015-01-01
The Antarctic Dry Valleys (ADV) provide a unique terrestrial analog for Martian surface processes as they are extremely cold and dry sedimentary environments. The surface geology and the chemical composition of the Dry Valleys that are similar to Mars suggest the possible presence of these soil-formation processes on Mars. The soils and sediments from Wright Valley, Antarctica were investigated in this study to examine mineralogical and chemical changes along the surface layer in this region and as a function of depth. Surface samples collected near Prospect Mesa and Don Juan Pond of the ADV were analyzed using visible/near-infrared (VNIR) and mid-IR reflectance spectroscopy and major and trace element abundances.
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Faunt, C.C.; Hanson, R.T.; Martin, P.; Schmid, W.
2011-01-01
California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence. ?? 2011 ASCE.
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Faunt, Claudia C.; Hanson, Randall T.; Martin, Peter; Schmid, Wolfgang
2011-01-01
California's Central Valley has been one of the most productive agricultural regions in the world for more than 50 years. To better understand the groundwater availability in the valley, the U.S. Geological Survey (USGS) developed the Central Valley hydrologic model (CVHM). Because of recent water-level declines and renewed subsidence, the CVHM is being updated to better simulate the geohydrologic system. The CVHM updates and refinements can be grouped into two general categories: (1) model code changes and (2) data updates. The CVHM updates and refinements will require that the model be recalibrated. The updated CVHM will provide a detailed transient analysis of changes in groundwater availability and flow paths in relation to climatic variability, urbanization, stream flow, and changes in irrigated agricultural practices and crops. The updated CVHM is particularly focused on more accurately simulating the locations and magnitudes of land subsidence. The intent of the updated CVHM is to help scientists better understand the availability and sustainability of water resources and the interaction of groundwater levels with land subsidence.
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Inland diatoms from the McMurdo Dry Valleys and James Ross Island, Antarctica
Esposito, R.M.M.; Spaulding, S.A.; McKnight, Diane M.; Van De Vijver, B.; Kopalova, K.; Lubinski, D.; Hall, B.; Whittaker, T.
2008-01-01
Diatom taxa present in the inland streams and lakes of the McMurdo Dry Valleys and James Ross Island, Antarctica, are presented in this paper. A total of nine taxa are illustrated, with descriptions of four new species (Luticola austroatlantica sp. nov., Luticola dolia sp. nov., Luticola laeta sp. nov., Muelleria supra sp. nov.). In the perennially ice-covered lakes of the McMurdo Dry Valleys, diatoms are confined to benthic mats within the photic zone. In streams, diatoms are attached to benthic surfaces and within the microbial mat matrix. One species, L. austroatlantica, is found on James Ross Island, of the southern Atlantic archipelago, and the McMurdo Dry Valleys. The McMurdo Dry Valley populations are at the lower range of the size spectrum for the species. Streams flow for 6-10 weeks during the austral summer, when temperatures and solar radiation allow glacial ice to melt. The diatom flora of the region is characterized by species assemblages favored under harsh conditions, with naviculoid taxa as the dominant group and several major diatom groups conspicuously absent. ?? 2008 NRC.
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Cold air drainage flows subsidize montane valley ecosystem productivity.
Novick, Kimberly A; Oishi, A Christopher; Miniat, Chelcy Ford
2016-12-01
In mountainous areas, cold air drainage from high to low elevations has pronounced effects on local temperature, which is a critical driver of many ecosystem processes, including carbon uptake and storage. Here, we leverage new approaches for interpreting ecosystem carbon flux observations in complex terrain to quantify the links between macro-climate condition, drainage flows, local microclimate, and ecosystem carbon cycling in a southern Appalachian valley. Data from multiple long-running climate stations and multiple eddy covariance flux towers are combined with simple models for ecosystem carbon fluxes. We show that cold air drainage into the valley suppresses local temperature by several degrees at night and for several hours before and after sunset, leading to reductions in growing season respiration on the order of ~8%. As a result, we estimate that drainage flows increase growing season and annual net carbon uptake in the valley by >10% and >15%, respectively, via effects on microclimate that are not be adequately represented in regional- and global-scale terrestrial ecosystem models. Analyses driven by chamber-based estimates of soil and plant respiration reveal cold air drainage effects on ecosystem respiration are dominated by reductions to the respiration of aboveground biomass. We further show that cold air drainage proceeds more readily when cloud cover and humidity are low, resulting in the greatest enhancements to net carbon uptake in the valley under clear, cloud-free (i.e., drought-like) conditions. This is a counterintuitive result that is neither observed nor predicted outside of the valley, where nocturnal temperature and respiration increase during dry periods. This result should motivate efforts to explore how topographic flows may buffer eco-physiological processes from macroscale climate change. © 2016 John Wiley & Sons Ltd.
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NASA Astrophysics Data System (ADS)
Posada, G.; Trujillo, J. C., Sr.; Hoyos, C.; Monsalve, G.
2017-12-01
The tectonics setting of Colombia is determined by the interaction of Nazca, Caribbean and South American plates, together with the Panama-Choco block collision, which makes a seismically active region. Regional seismic monitoring is carried out by the National Seismological Network of Colombia and the Accelerometer National Network of Colombia. Both networks calculate locations, magnitudes, depths and accelerations, and other seismic parameters. The Medellín - Aburra Valley is located in the Northern segment of the Central Cordillera of Colombia, and according to the Colombian technical seismic norm (NSR-10), is a region of intermediate hazard, because of the proximity to seismic sources of the Valley. Seismic monitoring in the Aburra Valley began in 1996 with an accelerometer network which consisted of 38 instruments. Currently, the network consists of 26 stations and is run by the Early Warning System of Medellin and Aburra Valley (SIATA). The technical advances have allowed the real-time communication since a year ago, currently with 10 stations; post-earthquake data is processed through operationally near-real-time, obtaining quick results in terms of location, acceleration, spectrum response and Fourier analysis; this information is displayed at the SIATA web site. The strong motion database is composed by 280 earthquakes; this information is the basis for the estimation of seismic hazards and risk for the region. A basic statistical analysis of the main information was carried out, including the total recorded events per station, natural frequency, maximum accelerations, depths and magnitudes, which allowed us to identify the main seismic sources, and some seismic site parameters. With the idea of a more complete seismic monitoring and in order to identify seismic sources beneath the Valley, we are in the process of installing 10 low-cost shake seismometers for micro-earthquake monitoring. There is no historical record of earthquakes with a magnitude
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USDA-ARS?s Scientific Manuscript database
Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...
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Dry Valley streams in Antarctica: Ecosystems waiting for water
McKnight, Diane M.; Niyogi, D.K.; Alger, A.S.; Bomblies, A.; Conovitz, P.A.; Tate, C.M.
1999-01-01
An axiom of ecology is: 'Where there is water, there is life.' In dry valley ecosystems of Antarctica, this axiom can be extended to: 'Where there has been and will be water, there is life.' Stream communities in the dry valleys can withstand desiccation on an annual basis and also for longer periods - as much as decades or even centuries. These intact ecosystems, consisting primarily of cyanobacteria and eukaryotic algae, spring back to life with the return of water. Soil organisms in the dry valleys also have remarkable survival capabilities (Virginia and Wall 1999), emerging from dormancy with the arrival of water. Streams in the dry valleys carry meltwater from a glacier or ice-field source to the lakes on the valley floors and generally flow for 4-10 weeks during the summer, depending on climatic conditions. Many of these streams contain abundant algal mats that are perennial in the sense that they are in a freeze-dried state during the winter and begin growing again within minutes of becoming wetted by the first flow of the season. The algal species present in the streams are mainly filamentous cyanobacteria (approximately 20 species of the genera Phormidium, Oscillatoria, and Nostoc), two green algal species of the genus Prasiola, and numerous diatom taxa that are characteristic of soil habitats and polar regions. Algal abundances are greatest in those streams in which periglacial processes, acting over periods of perhaps a century, have produced a stable stone pavement in the streambed. This habitat results in a less turbulent flow regime and limits sediment scour from the streambed. Because dry valley glaciers advance and retreat over periods of centuries and millennia and stream networks in the dry valleys evolve through sediment deposition and transport, some of the currently inactive stream channels may receive flow again in the future. Insights- into the process of algal persistence and reactivation will come from long-term experiments that study the
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Community-driven Environmental Solutions in EPA’s Pacific Southwest Region
This fact sheet describes accomplishments in community-driven environmental Solutions in EPA’s Pacific Southwest Region, including Imperial Valley (CA), American Samoa, Las Vegas Valley (NV), Gila River Indian Community (AZ) and Gilroy (CA).
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NASA Technical Reports Server (NTRS)
Bechtold, I. C. (Principal Investigator)
1974-01-01
The author has identified the following significant results. A study of Greenwater Valley indicates that the valley is bounded on the north and east by faults, on the south by a basement high, and on the west by the dip slope of the black mountains, movement of ground water from the valley is thus Movement of ground water from the valley is thus restricted, indicating the valley is a potential water reservoir.
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Early diagenetic microporosity in the Cotton Valley Limestone of east Texas
NASA Astrophysics Data System (ADS)
Ahr, Wayne M.
1989-07-01
The Upper Jurassic, Cotton Valley Limestone was deposited on a mature ramp where monotonous, regional slopes were punctuated by salt-generated structures and basement topography. The strandline and the crests of paleobathymetric highs were blanketed by oolitic and palletoidal grainstones. The ratio of grainstones to mudstones increases in the upper Cotton Valley, reflecting a regional shallowing phase. Thinner, shoaling-upward sequences are present but they do not correlate easily, especially from basement highs to salt domes, probably because salt movement occurred during deposition of Cotton Valley rocks. The complex diagenetic history of the Cotton Valley, inferred from cross-cutting features observed in thin section and from trace-element and stable-isotope content, includes the origin of "chalky" microporosity, especially in ooids. This intraparticle, intercrystalline porosity occurs in a fabric of equant, subhedral to euhedral, low-Mg calcite micro-rhombs which appear to have developed at the expense of an acicular precursor. Such microporous ooids are present mainly on the crests of paleobathymetric highs; nearby, offstructure ooids contain a mixture of micritic and well-preserved ooids. However, these micritic ooids are different from the micro-rhombic, microporous ones on the highs. The well-preserved low-Mg calcite ooids from offstructure positions exhibit relict acicular microstructures in some of their lamellae. The "chalky" microporosity is crosscut by virtually every other diagenetic feature in the Cotton Valley Limestone. The ɛ 13C values from individual microporous ooids range from +1.65 to +2.76% PDB, which is not in the range of values associated with precipitation in a hydrocarbon-rich environment. The formation of microporosity was followed by the formation of embayed grain contacts, pore-filling cementation, grain compaction, stylolite formation, replacements by quartz and rhombic dolomite, fracturing, fracture-filling cementation, saddle
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Measuring ground movement in geothermal areas of Imperial Valley, California
NASA Technical Reports Server (NTRS)
Lofgren, B. E.
1974-01-01
Significant ground movement may accompany the extraction of large quantities of fluids from the subsurface. In Imperial Valley, California, one of the potential hazards of geothermal development is the threat of both subsidence and horizontal movement of the land surface. Regional and local survey nets are being monitored to detect and measure possible ground movement caused by future geothermal developments. Precise measurement of surface and subsurface changes will be required to differentiate man-induced changes from natural processes in this tectonically active region.
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NASA Astrophysics Data System (ADS)
Mills, S. C.; Grab, S. W.
2009-04-01
Despite considerable research attention on apparent periglacial, glacial and sedimentary phenomena in the Maluti-Drakensberg alpine environment, knowledge on the Quaternary environmental history of this important watershed and climate-divide is still rather rudimentary. The dearth of Quaternary environmental indicators (proxy data) in the high Drakensberg is partly owing to the harsh climate (e.g. high wind speeds and high seasonal precipitation), which offers a poor preservation of past biological remains (e.g. bones, dung, middens, pollen). Possibly the best opportunity to reconstruct high Drakensberg palaeoenvironments is from sedimentary sequences exposed along fluvially-incised valley fills. The upper Sehonghong River (3000 to 3200 m a.s.l.) flows in a westerly direction and is flanked by north- and south-facing slopes reaching 3465 m a.s.l. Sediment is exposed on both the north- and south-facing slopes along the river. Despite uniform regional environmental conditions (geology, topography, climate, vegetation), there is a notable absence of similar north-facing deposits in adjacent upper valley catchments to the north and south of Sehonghong Valley. The upper Sehonghong Valley thus presents somewhat ‘unique' evidence for palaeo-slope mass movement in this alpine region. Thick colluvial deposits are most prominent on the south-facing slopes along the Sehonghong River and occur at altitudes between 3100 m a.s.l. and 3150 m a.s.l. The colluvial mantles are approximately 7 m in thickness, however reach up to 13 m in some areas. Although the north-facing lower valley side-slopes are generally absent of deposits, the notable exception is the thick stratified deposit located a few kilometres upstream. Whilst the south-facing deposits are relatively uniform in nature, the north-facing deposits consist of alternating units of gravel and organic sediment, dated to 36 600 ± 1400 14C yrs BP, and reflecting environmental changes during the Late Pleistocene. Mass
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NASA Astrophysics Data System (ADS)
He, Xiulan; Sonnenborg, Torben O.; Jørgensen, Flemming; Jensen, Karsten H.
2017-03-01
Stationarity has traditionally been a requirement of geostatistical simulations. A common way to deal with non-stationarity is to divide the system into stationary sub-regions and subsequently merge the realizations for each region. Recently, the so-called partition approach that has the flexibility to model non-stationary systems directly was developed for multiple-point statistics simulation (MPS). The objective of this study is to apply the MPS partition method with conventional borehole logs and high-resolution airborne electromagnetic (AEM) data, for simulation of a real-world non-stationary geological system characterized by a network of connected buried valleys that incise deeply into layered Miocene sediments (case study in Denmark). The results show that, based on fragmented information of the formation boundaries, the MPS partition method is able to simulate a non-stationary system including valley structures embedded in a layered Miocene sequence in a single run. Besides, statistical information retrieved from the AEM data improved the simulation of the geology significantly, especially for the deep-seated buried valley sediments where borehole information is sparse.
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Code of Federal Regulations, 2013 CFR
2013-04-01
... Chiles Valley. (a) Name. The name of the viticultural area described in this section is “Chiles Valley... viticultural area are four 1:24,000 Scale U.S.G.S. topography maps. They are titled: (1) St. Helena, CA 1960 photorevised 1980; (2) Rutherford, CA 1951 photorevised 1968; (3) Chiles Valley, CA 1958 photorevised 1980; (4...
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Taboada, B; Isa, P; Gutiérrez-Escolano, A L; Del Ángel, R M; Ludert, J E; Vázquez, N; Tapia-Palacios, M A; Chávez, P; Garrido, E; Espinosa, A C; Eguiarte, L E; López, S; Souza, V; Arias, C F
2018-06-01
The Cuatro Ciénegas Basin (CCB) is located in the Chihuahuan desert in the Mexican state of Coahuila; it has been characterized as a site with high biological diversity despite its extreme oligotrophic conditions. It has the greatest number of endemic species in North America, containing abundant living microbialites (including stromatolites and microbial mats) and diverse microbial communities. With the hypothesis that this high biodiversity and the geographic structure should be reflected in the virome, the viral communities in 11 different locations of three drainage systems, Churince, La Becerra, and Pozas Rojas, and in the intestinal contents of 3 different fish species, were analyzed for both eukaryotic and prokaryotic RNA and DNA viruses using next-generation sequencing methods. Double-stranded DNA (dsDNA) virus families were the most abundant (72.5% of reads), followed by single-stranded DNA (ssDNA) viruses (2.9%) and ssRNA and dsRNA virus families (0.5%). Thirteen families had dsDNA genomes, five had ssDNA, three had dsRNA, and 16 had ssRNA. A highly diverse viral community was found, with an ample range of hosts and a strong geographical structure, with very even distributions and signals of endemicity in the phylogenetic trees from several different virus families. The majority of viruses found were bacteriophages but eukaryotic viruses were also frequent, and the large diversity of viruses related to algae were a surprise, since algae are not evident in the previously analyzed aquatic systems of this ecosystem. Animal viruses were also frequently found, showing the large diversity of aquatic animals in this oasis, where plants, protozoa, and archaea are rare. IMPORTANCE In this study, we tested whether the high biodiversity and geographic structure of CCB is reflected in its virome. CCB is an extraordinarily biodiverse oasis in the Chihuahuan desert, where a previous virome study suggested that viruses had followed the marine ancestry of the marine
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Meter-Scale Characteristics of Martian Channels and Valleys
Carr, M.H.; Malin, M.C.
2000-01-01
Mars Global Surveyor images, with resolutions as high as 1.5 m pixel, enable characterization of martian channels and valleys at resolutions one to two orders of magnitude better than was previously possible. A major surprise is the near-absence of valleys a few hundred meters wide and narrower. The almost complete absence of fine-scale valleys could be due to lack of precipitation, destruction of small valleys by erosion, or dominance of infiltration over surface runoff. V-shaped valleys with a central channel, such as Nanedi Vallis, provide compelling evidence for sustained or episodic flow of water across the surface. Larger valleys appear to have formed not by headward erosion as a consequence of groundwater sapping but by erosion from water sources upstream of the observed sections. The freshest appearing valleys have triangular cross sections, with talus from opposing walls meeting at the center of the valley. The relations suggest that the width of the valleys is controlled by the depth of incision and the angle of repose of the walls. The flat floors of less fresh-appearing valleys result primarily from later eolian fill. Several discontinuous valleys and lines of craters suggest massive subsurface solution or erosion. The climatic implications of the new images will remain obscure until the cause for the scarcity of fine-scale dissection is better understood. ?? 2000 Academic Press.
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Solar Energy within the Central Valley, CA: Current Practices and Potential
NASA Astrophysics Data System (ADS)
Hoffacker, M. K.; Hernandez, R. R.; Allen, M. F.
2015-12-01
Utility-scale solar energy (USSE, ≥ 1 megawatt [MW]) systems are rapidly being deployed in the Central Valley of California, generating clean electricity and new job opportunities. Utility-scale solar energy systems require substantial quantities of land or space, often prompting an evaluation of environmental impacts and trade-offs when selecting their placement. Utilizing salt-contaminated agricultural land (as the sodium absorption and electrical conductivity values are unsuitably high), unsuitable for food production, and lands within the built environment (developed), can serve as a co-benefit opportunity when reclamation of these lands for USSE development is prioritized. In this study, we quantify the theoretical and generation-based solar energy potential for the Central Valley according to land-cover type, crop type, and for salt-contaminated lands. Further, we utilize the Carnegie Energy and Environmental Compatibility (CEEC) model to identify and prioritize solar energy, integrating environmental resource opportunities and constraints most relevant to the Central Valley. We use the CEEC model to generate a value-based environmental compatibility output for the Central Valley. The Central Valley extends across nearly 60,000 km2 of California with the potential of generating 21,800 - 30,300 TWh y-1 and 41,600 TWh y-1 of solar energy for photovoltaic (PV) and concentrating solar power (CSP), respectively. Pasture, hay, and cultivated crops comprise over half of the Central Valley, much of which is considered prime agriculture or of statewide or local importance for farming (28,200 km2). Together, approximately one-third of this region is salt-contaminated (16%) or developed (11%). This confers a generation-based potential of 5713 - 7891 TWh y-1 and 2770 TWh y-1 for PV and CSP, respectively. As energy, food, and land are inextricably linked, our study shows how land favorable for renewable energy systems can be used more effectively in places where land is
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NASA Astrophysics Data System (ADS)
Schubert, Brian A.; Lowenstein, Tim K.; Timofeeff, Michael N.
2009-06-01
Primary fluid inclusions in halite crystallized in Saline Valley, California, in 1980, 2004-2005, and 2007, contain rod- and coccoid-shaped microparticles the same size and morphology as archaea and bacteria living in modern brines. Primary fluid inclusions from a well-dated (0-100,000 years), 90 m long salt core from Badwater Basin, Death Valley, California, also contain microparticles, here interpreted as halophilic and halotolerant prokaryotes. Prokaryotes are distinguished from crystals on the basis of morphology, optical properties (birefringence), and uniformity of size. Electron micrographs of microparticles from filtered modern brine (Saline Valley), dissolved modern halite crystals (Saline Valley), and dissolved ancient halite crystals (Death Valley) support in situ microscopic observations that prokaryotes are present in fluid inclusions in ancient halite. In the Death Valley salt core, prokaryotes in fluid inclusions occur almost exclusively in halite precipitated in perennial saline lakes 10,000 to 35,000 years ago. This suggests that trapping and preservation of prokaryotes in fluid inclusions is influenced by the surface environment in which the halite originally precipitated. In all cases, prokaryotes in fluid inclusions in halite from the Death Valley salt core are miniaturized (<1 μm diameter cocci, <2.5 μm long, very rare rod shapes), which supports interpretations that the prokaryotes are indigenous to the halite and starvation survival may be the normal response of some prokaryotes to entrapment in fluid inclusions for millennia. These results reinforce the view that fluid inclusions in halite and possibly other evaporites are important repositories of microbial life and should be carefully examined in the search for ancient microorganisms on Earth, Mars, and elsewhere in the Solar System.
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Valley Vortex States in Sonic Crystals
NASA Astrophysics Data System (ADS)
Lu, Jiuyang; Qiu, Chunyin; Ke, Manzhu; Liu, Zhengyou
2016-03-01
Valleytronics is quickly emerging as an exciting field in fundamental and applied research. In this Letter, we study the acoustic version of valley states in sonic crystals and reveal a vortex nature of such states. In addition to the selection rules established for exciting valley polarized states, a mimicked valley Hall effect of sound is proposed further. The extraordinary chirality of valley vortex states, detectable in experiments, may open a new possibility in sound manipulations. This is appealing to scalar acoustics that lacks a spin degree of freedom inherently. In addition, the valley selection enables a handy way to create vortex matter in acoustics, in which the vortex chirality can be controlled flexibly. Potential applications can be anticipated with the exotic interaction of acoustic vortices with matter, such as to trigger the rotation of the trapped microparticles without contact.
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NASA Astrophysics Data System (ADS)
Wei, K.; Song, S.; Huang, C.
2003-12-01
Availability of water, and response to shortage of it, plays an important role in shaping human history. Near a century ago, Ellsworth Huntington (1907) suggested that the developments of ancient civilizations in Inner Asian and their invasions into China and Europe were pulsed by climatic changes. In revisiting this proposition, here we present a paleoclimatic record of the past 5000 years deduced from carbon isotopic ratio of organic carbon and percentage of aragonite in bulk sediments of a radiometrically dated sedimentary core of Lake Bosten, Xinjiang, China. Together the two proxies of aridity provide a detailed record of climatic fluctuation of the Inner Asia. The arid periods are well characterized by high content of authigenic aragonite and heavier values of carbon isotopic ratio of organic carbon in the bulk sediments (implying dominance of C4 plants which thrived under arid condition). Conversely, the humid/wet periods are marked by lighter carbon isotopic values (indicating presence of C3 plants of humid climateœcand absence of aragonite. The Western Region (Xi-Y"1) area of China enjoyed a long period of stable and humid condition from 2nd century B.C. to the 8th century when many oasis city-states were established and Buddhism spread from India. A drastic deterioration of climate during the eighth century appears to cause the decline of those once strived ancient civilizations in the eastern side of the Tarim Basin along the Silk Routes.
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Topological Valley Transport in Two-dimensional Honeycomb Photonic Crystals.
Yang, Yuting; Jiang, Hua; Hang, Zhi Hong
2018-01-25
Two-dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.
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Geomorphic controls on Pleistocene knickpoint migration in Alpine valleys
NASA Astrophysics Data System (ADS)
Leith, Kerry; Fox, Matt; Moore, Jeffrey R.; Brosda, Julian; Krautblatter, Michael; Loew, Simon
2014-05-01
Recent insights into sub-glacial bedrock stress conditions suggest that the erosional efficiency of glaciers may reduce markedly following a major erosional cycle [Leith et al., 2013]. This implies that the formation of large glacial valleys within the Alps is likely to have occurred shortly after the onset of 100 ky glacial-interglacial cycles (at the mid-Pleistocene Revolution (MPR)). The majority of landscape change since this time may have therefore been driven by sub-aerial processes. This hypothesis is supported by observations of hillslope and channel morphology within Canton Valais (Switzerland), where major tributary valleys display a common morphology along their length, hinting at a shared geomorphic history. Glaciers currently occupy the headwaters of many catchments, while the upper reaches of rivers flow across extensive alluvial planes before abruptly transitioning to steep channels consisting of mixed bedrock and talus fan deposits. The rivers then converge to flow out over the alluvial plane of the Rhone Valley. Characteristically rough topographies within the region are suggested to mark the progressive transition from a glacial to fluvially-dominated landscape, and correlate well with steepened river channel sections determined from a 2.5 m resolution LiDAR DEM. We envisage a landscape in which ongoing tectonic uplift drives the emergence of Alpine bedrock through massive sedimentary valley infills (currently concentrated in the Rhone Valley), whose elevation is fixed by the consistent fluvial baselevel at Lake Geneva. As fluvial incision ceases at the onset of glaciation, continued uplift causes the formation of knickpoints at the former transition from bedrock to sedimentary infill. These knickpoints will then propagate upstream during subsequent interglacial periods. By investigating channel morphologies using an approach based on the steady-state form of the stream power equation, we can correlate steepened channel reaches (degraded
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NASA Astrophysics Data System (ADS)
Dalton, T. A.; Daniels, J. J.
2009-12-01
The development of geological carbon sequestration within the Ohio River Valley is of major interest to the national electricity and coal industries because the Valley is home to a heavy concentration of coal-burning electricity generation plants and the infrastructure is impossible to eliminate in the short-term. It has been determined by Ohio's politicians and citizenry that the continued use of coal in this region until alternative energy supplies are available will be necessary over the next few years. Geologic sequestration is the only possible means of keeping the CO2 out of the atmosphere in the region. The cost of the sequestration effort greatly decreases CO2 emissions by sequestering CO2 directly on site of these plants, or by minimizing the distance between fossil-fueled generation and sequestration (i.e., by eliminating the cost of transportation of supercritical CO2 from plant to sequestration site). Thus, the practicality of CO2 geologic sequestration within the Ohio River Valley is central to the development of such a commercial effort. Though extensive work has been done by the Regional Partnerships of the DOE/NETL in the characterization of general areas for carbon sequestration throughout the nation, few projects have narrowed their focus into a single geologic region in order to evaluate the sites of greatest commercial potential. As an undergraduate of the Earth Sciences at Ohio State, I have engaged in thorough research to obtain a detailed understanding of the geology of the Ohio River Valley and its potential for commercial-scale carbon sequestration. Through this research, I have been able to offer an estimate of the areas of greatest interest for CO2 geologic sequestration. This research has involved petrological, mineralogical, geochemical, and geophysical analyses of four major reservoir formations within Ohio—the Rose Run, the Copper Ridge, the Clinton, and the Oriskany—along with an evaluation of the possible effects of injection
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Optical tuning of electronic valleys (Conference Presentation)
NASA Astrophysics Data System (ADS)
Sie, Edbert J.; Gedik, Nuh
2017-02-01
Monolayer transition-metal dichalcogenides such as MoS2 and WS2 are prime examples of atomically thin semiconducting crystals that exhibit remarkable electronic and optical properties. They have a pair of valleys that can serve as a new electronic degree of freedom, and these valleys obey optical selection rules with circularly polarized light. Here, we discuss how ultrafast laser pulses can be used to tune their energy levels in a controllable valley-selective manner. The energy tunability is extremely large, comparable to what would be obtained using a hundred Tesla of magnetic field. We will also show that such valley tunability can be performed while we effectively manipulate the valley selection rules. Finally, we will explore the prospect of using this technique through photoemission spectroscopy to create a new phase of matter called a valley Floquet topological insulator.
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[Gamasid mites (Gamasina) of rodents in the natural biotopes of Tchui Valley].
Fedorova, S Zh; Tranbaev, Zh M
2005-01-01
The recent fauna of gamasid mites parasitising rodents in the natural biotopes of Tchui Valley (Kyrgyzstan) in investigated. 32 species of Gamasina are revealed, of which 9 are recorded in the region for the first time. A checklist of the gamasid mites is given.
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NASA Astrophysics Data System (ADS)
Herrera, L.; Hoyos Ortiz, C. D.
2017-12-01
The spatio-temporal evolution of the Atmospheric Boundary Layer (ABL) in the Aburrá Valley, a narrow highly complex mountainous terrain located in the Colombian Andes, is studied using different datasets including radiosonde and remote sensors from the meteorological network of the Aburrá Valley Early Warning System. Different techniques are developed in order to estimate Mixed Layer Height (MLH) based on variance of the ceilometer backscattering profiles. The Medellín metropolitan area, home of 4.5 million people, is located on the base and the hills of the valley. The generally large aerosol load within the valley from anthropogenic emissions allows the use of ceilometer retrievals of the MLH, especially under stable atmospheric conditions (late at night and early in the morning). Convective atmospheres, however, favor the aerosol dispersion which in turns increases the uncertainty associated with the estimation of the Convective Boundary Layer using ceilometer retrievals. A multi-sensor technique is also developed based on Richardson Number estimations using a Radar Wind Profiler combined with a Microwave Radiometer. Results of this technique seem to be more accurate thorough the diurnal cycle. ABL retrievals are available from October 2014 to April 2017. The diurnal cycle of the ABL exhibits monomodal behavior, highly influenced by the evolution of the potential temperature profile, and the turbulent fluxes near the surface. On the other hand, the backscattering diurnal cycle presents a bimodal structure, showing that the amount of aerosol particles at the lower troposphere is strongly influenced by anthropogenic emissions, dispersion conditioned by topography and by the ABL dynamics, conditioning the available vertical height for the pollutants to interact and disperse. Nevertheless, the amount, distribution or type of atmospheric aerosols does not appear to have a first order influence on the MLH variations or evolution. Results also show that intra
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NASA Astrophysics Data System (ADS)
Harlow, R. C.; Blockley, E. W.; Brooks, I. M.; Essery, R.; Milton, S.; Renfrew, I.; Vosper, S.
2016-12-01
The spatio-temporal evolution of the Atmospheric Boundary Layer (ABL) in the Aburrá Valley, a narrow highly complex mountainous terrain located in the Colombian Andes, is studied using different datasets including radiosonde and remote sensors from the meteorological network of the Aburrá Valley Early Warning System. Different techniques are developed in order to estimate Mixed Layer Height (MLH) based on variance of the ceilometer backscattering profiles. The Medellín metropolitan area, home of 4.5 million people, is located on the base and the hills of the valley. The generally large aerosol load within the valley from anthropogenic emissions allows the use of ceilometer retrievals of the MLH, especially under stable atmospheric conditions (late at night and early in the morning). Convective atmospheres, however, favor the aerosol dispersion which in turns increases the uncertainty associated with the estimation of the Convective Boundary Layer using ceilometer retrievals. A multi-sensor technique is also developed based on Richardson Number estimations using a Radar Wind Profiler combined with a Microwave Radiometer. Results of this technique seem to be more accurate thorough the diurnal cycle. ABL retrievals are available from October 2014 to April 2017. The diurnal cycle of the ABL exhibits monomodal behavior, highly influenced by the evolution of the potential temperature profile, and the turbulent fluxes near the surface. On the other hand, the backscattering diurnal cycle presents a bimodal structure, showing that the amount of aerosol particles at the lower troposphere is strongly influenced by anthropogenic emissions, dispersion conditioned by topography and by the ABL dynamics, conditioning the available vertical height for the pollutants to interact and disperse. Nevertheless, the amount, distribution or type of atmospheric aerosols does not appear to have a first order influence on the MLH variations or evolution. Results also show that intra
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Regional nitrate and pesticide trends in ground water in the eastern San Joaquin Valley, California
Burow, K.R.; Shelton, James L.; Dubrovsky, N.M.
2008-01-01
Protection of ground water for present and future use requires monitoring and understanding of the mechanisms controlling long-term quality of ground water. In this study, spatial and temporal trends in concentrations of nitrate and pesticides in ground water in the eastern San Joaquin Valley, California, were evaluated to determine the long-term effects of agricultural and urban development on regional ground-water quality. Trends in concentrations of nitrate, the nematocide 1,2-dibromo-3-chloropropane, and the herbicide simazine during the last two decades are generally consistent with known nitrogen fertilizer and pesticide use and with the position of the well networks in the regional ground-water flow system. Concentrations of nitrate and pesticides are higher in the shallow part of the aquifer system where domestic wells are typically screened, whereas concentrations are lower in the deep part of the aquifer system where public-supply wells are typically screened. Attenuation processes do not seem to significantly affect concentrations. Historical data indicate that concentrations of nitrate have increased since the 1950s in the shallow and deep parts of the aquifer system. Concentrations of nitrate and detection of pesticides in the deep part of the aquifer system will likely increase as the proportion of highly affected water contributed to these wells increases with time. Because of the time of travel between the water table and the deep part of the aquifer system, current concentrations in public-supply wells likely reflect the effects of 40- to 50-yr-old management practices. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
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Martian oceans, valleys and climate
Carr, M.H.
2000-01-01
The new Mars Global Surveyor altimetry shows that the heavily cratered southern hemisphere of Mars is 5 km higher that the sparely cratered plains of the northern hemisphere. Previous suggestions that oceans formerly occupied that northern plains as evidenced by shorelines are partly supported by the new data. A previously identified outer boundary has a wide range of elevations and is unlikely to be a shoreline but an inner contact with a narrow range of elevations is a more likely candidate. No shorelines are visible in the newly acquired, 2.5 metre/pixel imaging. Newly imaged valleys provide strong support for sustained or episodic flow of water across the Martian surface. A major surprise, however, is the near absence of valleys less than 100 m across. Martian valleys seemingly do not divide into ever smaller valleys as terrestrial valleys commonly do. This could be due to lack of precipitation or lack of surface runoff because of high infiltration rates. High erosion rates and supports warm climates and presence of large bodies of water during heavy bombardment. The climate history and fate of the water after heavy bombardment remain cotroversial.
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Evidence for precipitation on Mars from dendritic valleys in the Valles Marineris area.
Mangold, Nicolas; Quantin, Cathy; Ansan, Véronique; Delacourt, Christophe; Allemand, Pascal
2004-07-02
Dendritic valleys on the plateau and canyons of the Valles Marineris region were identified from Thermal Emission Imaging System (THEMIS) images taken by Mars Odyssey. The geomorphic characteristics of these valleys, especially their high degree of branching, favor formation by atmospheric precipitation. The presence of inner channels and the maturity of the branched networks indicate sustained fluid flows over geologically long periods of time. These fluvial landforms occur within the Late Hesperian units (about 2.9 to 3.4 billion years old), when Mars was thought to have been cold. Our results suggest a period of warmer conditions conducive to hydrological activity.
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Ptacek, Travis; Crowley, Michael; Swain, Ashit K.; Osborne, John D.; Bej, Asim K.; Andersen, Dale T.
2014-01-01
Hymenobacter sp. IS2118, isolated from a freshwater lake in Schirmacher Oasis, Antarctica, produces extracellular polymeric substance (EPS) and manifests tolerance to cold, UV radiation (UVR), and oxidative stress. We report the 5.26-Mb draft genome of strain IS2118, which will help us to understand its adaptation and survival mechanisms in Antarctic extreme ecosystems. PMID:25103756
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Fu, Qi; Li, Bo; Hou, Ying; Bi, Xu; Zhang, Xinshi
2017-12-31
The sustainable use of ecosystem services (ES) can contribute to enhancing human well-being. Understanding the effects of land use and climate change on ES can provide scientific and targeted guidance for the sustainable use of ES. The objective of this study was to reveal the way in which land use and climate change influence the spatial and temporal variations of ES in the mountain-oasis-desert system (MODS). In this study, we assessed water yield, soil conservation, crop production, and sand fixation in 1990, 2000, and 2010 in Altay Prefecture, which is representative of the MODS, based on widely used biophysical models. Moreover, we analyzed the effects of different land use and climate change conditions on ES. The results show that the area of forest and bare land decreased in Altay Prefecture. In contrast, the area of grassland with low coverage and cropland increased. The climate of this area presented an overall warming-wetting trend, with warming-drying and cooling-wetting phenomena in some areas. Soil conservation in the mountain zone, water yield in the oasis zone, and sand fixation in the desert zone all decreased under the influence of land use change alone. The warming-drying trend led to decreased water yield in the oasis zone and increased wind erosion in the desert zone. Based on the results, we recommend that local governments achieve sustainable use of ES by planting grasslands with high coverage in the oasis zone, increasing investment in agricultural science and technology, and establishing protected areas in the mountain and desert zones. The methodology in our study can also be applied to other regions with a MODS structure. Copyright © 2017 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Arvani, Barbara; Pierce, R. Bradley; Lyapustin, Alexei I.; Wang, Yujie; Ghermandi, Grazia; Teggi, Sergio
2016-09-01
In this work, the new 1 km-resolved Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm is employed to characterize seasonal PM10 - AOD correlations over northern Italy. The accuracy of the new dataset is assessed compared to the widely used Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 5.1 Aerosol Optical Depth (AOD) data, retrieved at 0.55 μm with spatial resolution of 10 km (MYD04_L2). We focused on evaluating the ability of these two products to characterize both temporal and spatial distributions of aerosols within urban and suburban areas. Ground PM10 measurements were obtained from 73 of the Italian Regional Agency for Environmental Protection (ARPA) monitoring stations, spread across northern Italy, during a three-year period from 2010 to 2012. The Po Valley area (northern Italy) was chosen as the study domain because of its severe urban air pollution, resulting from it having the highest population and industrial manufacturing density in the country, being located in a valley where two surrounding mountain chains favor the stagnation of pollutants. We found that the global correlations between the bin-averaged PM10 and AOD are R2 = 0.83 and R2 = 0.44 for MYD04_L2 and for MAIAC, respectively, suggesting a greater sensitivity of the high-resolution product to small-scale deviations. However, the introduction of Relative Humidity (RH) and Planetary Boundary Layer (PBL) depth corrections allowed for a significant improvement to the bin-averaged PM - AOD correlation, which led to a similar performance: R2 = 0.96 for MODIS and R2 = 0.95 for MAIAC. Furthermore, the introduction of the PBL information in the corrected AOD values was found to be crucial in order to capture the clear seasonal cycle shown by measured PM10 values. The study allowed us to define four seasonal linear correlations that estimate PM10 concentrations satisfactorily from the remotely sensed MAIAC AOD retrieval. Overall, the results show that the high
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NASA Technical Reports Server (NTRS)
Arvani, Barbara; Pierce, R. Bradley; Lyapustin, Alexei I.; Wang, Yujie; Ghermandi, Grazia; Teggi, Sergio
2016-01-01
In this work, the new 1-km-resolved Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm is employed to characterize seasonal AOD-PM10 correlations over northern Italy. The accuracy of the new dataset is assessed versus the widely used Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 5.1 Aerosol Optical Depth (AOD) data, retrieved at 0.55 microns with spatial resolution of 10 km (MYD04). We focused on evaluating the ability of these two products to characterize both temporal and spatial distributions of aerosols within urban and suburban areas. Ground PM10 measurements were obtained from 73 of the Italian Regional Agency for Environmental Protection (ARPA) monitoring stations, spread across northern Italy, for a three-year period from 2010 to 2012. The Po Valley area (northern Italy) was chosen as the study domain because of severe urban air pollution, resulting from the highest population and industrial manufacturing density in the country, being located in a valley where two surrounding mountain chains favor the stagnation of pollutants. We found that the global correlations between PM10 and AOD are R(sup 2) = 0.83 and R(sup 2) = 0.44 for MYD04_L2 and for MAIAC, respectively, suggesting for a greater sensitiveness of the high-resolution product to small-scale deviations. However, the introduction of Relative Humidity (RH) and Planetary Boundary Layer (PBL) depth corrections gave a significant improvement to the PM AOD correlation, which led to similar performance: R(sup 2) = 0.96 for MODIS and R(sup 2) = 0.95 for MAIAC. Furthermore, the introduction of the PBL information in the corrected AOD values was found to be crucial in order to capture the clear seasonal cycle shown by measured PM10 values. The study allowed us to define four seasonal linear correlations that estimate PM10 concentrations satisfactorily from the remotely sensed MAIAC AOD retrieval. Overall, the results show that the high resolution provided by MAIAC
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Thatcher, W.; Massonnet, D.
1997-01-01
Satellite radar interferometric images of Long Valley caldera show a pattern of surface deformation that resembles that expected from analysis of an extensive suite of ground-based geodetic data. Images from 2 and 4 year intervals respectively, are consistent with uniform movement rates determined from leveling surveys. Synthetic interferograms generated from ellipsoidal-inclusion source models based on inversion of the ground-based data show generally good agreement with the observed images. Two interferograms show evidence for a magmatic source southwest of the caldera in a region not covered by ground measurements. Poorer image quality in the 4 year interferogram indicates that temporal decorrelation of surface radar reflectors is progressively degrading the fringe pattern in the Long Valley region. Copyright 1997 by the American Geophysical Union.
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Krusic, A.G.; Prentice, M.L.; Licciardi, J.M.
2009-01-01
Early-mid Pliocene moraines in the McMurdo Dry Valleys, Antarctica, are more extensive than the present alpine glaciers in this region, indicating substantial climatic differences between the early-mid Pliocene and the present. To quantify this difference in the glacier-climate regime, we estimated the equilibrium-line altitude (ELA) change since the early-mid Pliocene by calculating the modern ELA and reconstructing the ELAs of four alpine glaciers in Wright and Taylor Valleys at their early-mid Pliocene maxima. The area-altitude balance ratio method was used on modern and reconstructed early-mid Pliocene hypsometry. In Wright and Victoria Valleys, mass-balance data identify present-day ELAs of 800-1600 m a.s.l. and an average balance ratio of 1.1. The estimated ELAs of the much larger early-mid Pliocene glaciers in Wright and Taylor Valleys range from 600 to 950 ?? 170 m a.s.l., and thus are 250-600 ??170 m lower than modern ELAs in these valleys. The depressed ELAs during the early-mid-Pliocene most likely indicate a wetter and therefore warmer climate in the Dry Valleys during this period than previous studies have recognized.
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Paleolimnology of the McMurdo Dry Valleys, Antarctica
NASA Technical Reports Server (NTRS)
Doran, P. T.; Wharton, R. A. Jr; Lyons, W. B.; Wharton RA, J. r. (Principal Investigator)
1994-01-01
The McMurdo Dry Valleys presently contain more than 20 permanent lakes and ponds, which vary markedly in character. All, with the exception of a hypersaline pond, have a perennial ice-cover. The dry valley lakes, and lakes in other ice-free regions of continental Antarctica, are unique on this planet in that they consistently maintain a thick year-round ice cover (2.8-6.0 m) over liquid water. The persistent ice covers minimize wind-generated currents and reduce light penetration, as well as restricting sediment deposition into a lake and the exchange of atmospheric gases between the water column and the atmosphere. From a paleolimnological perspective, the dry valley lakes offer an important record of catchment and environmental changes. These lakes are also modern-day equivalents of periglacial lakes that were common during glacial periods at temperate latitudes. The present lakes are mostly remnants of larger glacial lakes that occupied the valleys in the past, perhaps up to 4.6 Ma ago. Two of the valleys contain evidence of being filled with large glacial lakes within the last 10000 years. Repeated drying and filling events since then have left a characteristic impression on the salt profiles of some lakes creating a unique paleo-indicator within the water column. These events are also marked in the sediments by the concentration and dilution of certain chemical constituents, particularly salts, and are also corroborated by carbonate speciation and oxygen isotope analysis. Stratigraphic analysis of dry valley lake sediments is made difficult by the occurrence of an 'old carbon' reservoir creating spurious radiocarbon dates, and by the high degree of spatial variability in lake sedimentation. From a biological perspective, the lakes are relatively simple, containing various taxa of planktonic and benthic microorganisms, but no higher forms of life, which is an advantage to paleolimnologists because there is no bioturbation in the sediments. Useful biological
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Paleolimnology of the McMurdo Dry Valleys, Antarctica.
Doran, P T; Wharton, R A; Lyons, W B
1994-01-01
The McMurdo Dry Valleys presently contain more than 20 permanent lakes and ponds, which vary markedly in character. All, with the exception of a hypersaline pond, have a perennial ice-cover. The dry valley lakes, and lakes in other ice-free regions of continental Antarctica, are unique on this planet in that they consistently maintain a thick year-round ice cover (2.8-6.0 m) over liquid water. The persistent ice covers minimize wind-generated currents and reduce light penetration, as well as restricting sediment deposition into a lake and the exchange of atmospheric gases between the water column and the atmosphere. From a paleolimnological perspective, the dry valley lakes offer an important record of catchment and environmental changes. These lakes are also modern-day equivalents of periglacial lakes that were common during glacial periods at temperate latitudes. The present lakes are mostly remnants of larger glacial lakes that occupied the valleys in the past, perhaps up to 4.6 Ma ago. Two of the valleys contain evidence of being filled with large glacial lakes within the last 10000 years. Repeated drying and filling events since then have left a characteristic impression on the salt profiles of some lakes creating a unique paleo-indicator within the water column. These events are also marked in the sediments by the concentration and dilution of certain chemical constituents, particularly salts, and are also corroborated by carbonate speciation and oxygen isotope analysis. Stratigraphic analysis of dry valley lake sediments is made difficult by the occurrence of an 'old carbon' reservoir creating spurious radiocarbon dates, and by the high degree of spatial variability in lake sedimentation. From a biological perspective, the lakes are relatively simple, containing various taxa of planktonic and benthic microorganisms, but no higher forms of life, which is an advantage to paleolimnologists because there is no bioturbation in the sediments. Useful biological
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Ground magnetometer survey in the Valley of Ten Thousand Smokes, Alaska. M.S. Thesis
NASA Technical Reports Server (NTRS)
Trible, M. C.
1972-01-01
A reconnaissance magnetometer survey was conducted with both total- and vertical-field magnetometers. The large, sharp, narrow total magnetic anomalies observed over a zone of relict fumaroles in Broken Mountain Valley showed spectacular agreement with the surficial geology. Such a correlation is a strong indication that accumulations of magnetic minerals have been preserved along these fissure vents at shallow depths. Since large magnetic anomalies were measured near fumarolic markings along all of the traverses, it is proposed that the retention of sublimates along fumarolic vents is common throughout the Valley. The generally concentric contours of the vertical magnetic anomaly at the head of the Valley suggest that the dome of Novarupta is merely the surficial expression of a very massive conical-shaped intrusive centered just northeast of the dome. The magnetometer survey indicates that the pyroclastics in the Valley may be over 150 meters thick. Such an estimate is compatible with the volume of eruptive material needed to compensate for the subsidence surrounding Novarupta as well as a sizable amount of other regional subsidence.