10. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC ...
10. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC RAILROAD INTERCHANGE TRACKS AT YAKIMA - Yakima Valley Transportation Company Interurban Railroad, Connecting towns of Yakima, Selah & Wiley City, Yakima, Yakima County, WA
11. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC ...
11. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC RAILROAD INTERCHANGE TRACKS AT YAKIMA, SHOWING DETAIL OF OVERHEAD WIRING - Yakima Valley Transportation Company Interurban Railroad, Connecting towns of Yakima, Selah & Wiley City, Yakima, Yakima County, WA
12. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC ...
12. VIEW OF YAKIMA VALLEY TRANSPORTATION COMPANY AND UNION PACIFIC RAILROAD INTERCHANGE TRACKS AT YAKIMA, SHOWING SOUTH END OF OVERHEAD WIRING TERMINATION - Yakima Valley Transportation Company Interurban Railroad, Connecting towns of Yakima, Selah & Wiley City, Yakima, Yakima County, WA
ERIC Educational Resources Information Center
Schuehler, Susan S.; And Others
A project entitled the LINK Program was undertaken to develop a model program of educational brokering through union locals and small businesses in the Lehigh Valley in Pennsylvania. Included among the major project activities were the following: contacting unions, presenting a model program to them, and soliciting support from union officials;…
Shelving plans, elevations, and sections. San Bernardino Valley Union Junior ...
Shelving plans, elevations, and sections. San Bernardino Valley Union Junior College, Science Building. Howard E. Jones, Architect, San Bernardino, California. Sheet 9, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
ERIC Educational Resources Information Center
Schwartzbeck, Terri Duggan
2013-01-01
The K-8 Cajon Valley Union School District (Cajon Valley USD) is one of forty-two school districts in the greater San Diego, California metropolitan area. Serving approximately 16,000 students, the Cajon Valley USD is extremely diverse; 36 percent of students are Hispanic, 46 percent are white, 7 percent are African American, and many students are…
South elevation and main floor plan. San Bernardino Valley Union ...
South elevation and main floor plan. San Bernardino Valley Union Junior College, Science Building. Includes chemistry and botany departments. Howard E. Jones, Architect, San Bernardino, California. Sheet 2, job no. 311. Scale 1/8 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
Foundation plan. San Bernardino Valley Union Junior College, Classics Building. ...
Foundation plan. San Bernardino Valley Union Junior College, Classics Building. Also includes sections AA-KK (except DD). Howard E. Jones, Architect, San Bernardino, California. Sheet 1, job no. 312. Scales 1/8 inch to the foot (plan) and 1/2 inch to the foot (sections). February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
South entrance, plan, section, & detail. San Bernardino Valley Union ...
South entrance, plan, section, & detail. San Bernardino Valley Union Junior College, Science Building. Detailed drawings of tile work, wrought iron, and art stone, Howard E. Jones, Architect, San Bernardino, California. Sheet 6, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
Details of main entrance. San Bernardino Valley Union Junior College, ...
Details of main entrance. San Bernardino Valley Union Junior College, Classics Building. Half elevation of exterior iron gates, half plan of interior with tiling, and section AA. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 312. Scale 1/2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
North elevation and second floor plan. San Bernardino Valley Union ...
North elevation and second floor plan. San Bernardino Valley Union Junior College, Science Building. Includes physics, geology, and zoology departments shelving. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, job no. 311. Scales 1/8 inch to the foot (elevations) and 1/2 inch to the foot (shelving). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
East and west elevations. San Berardino Valley Union Junior College, ...
East and west elevations. San Berardino Valley Union Junior College, Science Building. Also includes elevations and sections of chemistry department shelving. Howard E. Jones, Architect, San Bernardino, California. Sheet 4, Job no. 311. Scales 1/8 inch to the foot (elevations) and 1/2 inch t other foot (shelving). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
West elevation. San Bernardino Valley Union Junior College, Science Building. ...
West elevation. San Bernardino Valley Union Junior College, Science Building. Also includes plan of entrance, section EE showing tiling and typical transom design, and a full size detail of a door jamb for inside concrete walls. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 311. Scale 1.2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
Technology Finds Its Place in Silicon Valley Schools
ERIC Educational Resources Information Center
Hundley, Paula; Scigliano, Marie
2012-01-01
Technology today is poised to usher in the best of times. Exploring what other districts do highlights the common themes as well as the unique challenges. Three very different districts in Silicon Valley--Portola Valley School District, Campbell Union School District and San Jose Unified School District--explain the strategies they use to enhance…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-15
... line beginning south of Sun Valley Boulevard (near UP milepost 56.50) that crosses Salt Creek and..., 2006). UP also leases: (1) The BNSF line near Sun Valley Boulevard (beginning near UP milepost 56.50) to the beginning point of the wye at BNSF milepost 0.62 (referred to as the Sun Valley Segment); and...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-08
...... 11/23/10 11/18/10 Plastics (Union). 74909 Heritage Valley Health Moon Township, PA..... 11/23/10 11... 11/20/10 Technologies, Inc. (Union). 74927 Pfizer, Inc. (Union)....... Pearl River, NY....... 11/26... Adjustment Assistance. APPENDIX TAA Petitions Instituted between 11/22/10 and 11/26/10 Date of Date of TA-W...
Evidence for Circulation of the Rift Valley Fever Virus among Livestock in the Union of Comoros
Soulé, Miradje; Faharoudine, Abdourahime; Foray, Coralie; Olive, Marie-Marie; Maquart, Marianne; Soulaimane, Abdouroihamane; Madi Kassim, Ahmed; Cêtre-Sossah, Catherine; Cardinale, Eric
2014-01-01
Rift Valley fever virus (RVFV) is an arthropod-borne phlebovirus reported to be circulating in most parts of Africa. Since 2009, RVFV has been suspected of continuously circulating in the Union of Comoros. To estimate the incidence of RVFV antibody acquisition in the Comorian ruminant population, 191 young goats and cattle were selected in six distinct zones and sampled periodically from April 2010 to August 2011. We found an estimated incidence of RVFV antibody acquisition of 17.5% (95% confidence interval (CI): [8.9–26.1]) with a significant difference between islands (8.2% in Grande Comore, 72.3% in Moheli and 5.8% in Anjouan). Simultaneously, a longitudinal entomological survey was conducted and ruminant trade-related information was collected. No RVFV RNA was detected out of the 1,568 blood-sucking caught insects, including three potential vectors of RVFV mosquito species. Our trade survey suggests that there is a continuous flow of live animals from eastern Africa to the Union of Comoros and movements of ruminants between the three Comoro islands. Finally, a cross-sectional study was performed in August 2011 at the end of the follow-up. We found an estimated RVFV antibody prevalence of 19.3% (95% CI: [15.6%–23.0%]). Our findings suggest a complex RVFV epidemiological cycle in the Union of Comoros with probable inter-islands differences in RVFV circulation patterns. Moheli, and potentially Anjouan, appear to be acting as endemic reservoir of infection whereas RVFV persistence in Grande Comore could be correlated with trade in live animals with the eastern coast of Africa. More data are needed to estimate the real impact of the disease on human health and on the national economy. PMID:25078616
7 CFR 27.93 - Bona fide spot markets.
Code of Federal Regulations, 2014 CFR
2014-01-01
..., East Texas and Oklahoma, West Texas, Desert Southwest and San Joaquin Valley. Such markets will... Desert Southwest Markets and the New Mexico counties of Union, Quay, Curry, Roosevelt and Lea. Desert... counties. San Joaquin Valley All California counties except those included in the Desert Southwest market...
75 FR 65331 - Federal Home Loan Bank Members Selected for Community Support Review
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-22
... Texas. Federal Home Loan Bank of Topeka--District 10 First Southwest Bank Alamosa Colorado. Fitzsimons Federal Credit Union Aurora Colorado. Boulder Municipal Employees FCU Boulder Colorado. Boulder Valley Credit Union Boulder Colorado. Flatirons Bank Boulder Colorado. 5Star Bank Colorado Springs Colorado...
Elevation and plan of east side entrance. San Bernardino Valley ...
Elevation and plan of east side entrance. San Bernardino Valley Union Junior College, Library Building. Also includes sections II and SS of entrance hall; and a stress diagram of steel truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 315. Scale 1/2 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
NASA Astrophysics Data System (ADS)
Yang, M. M.; Blake, D. R.
2009-12-01
The San Joaquin Valley Air Basin in Central California is plagued with air quality problems, and is classified by the U.S. Environmental Protection Agency (EPA) as a serious non-attainment area for health-based eight-hour federal ozone (smog) standard (1). One of the main sources of Volatile Organic Compounds (VOCs), and indirect sources of ozone in the Valley, has been identified as dairy farming (2). Among these compounds, we have found that several OVOCs such as ethanol, methanol, acetone and acetaldehyde are produced in major quantities throughout the San Joaquin valley as by-products of yeast fermentation of silage and photochemical oxidation. These oxygenates, especially ethanol, play an important role in ozone (O3) formation within the valley. Since 2008, several different types of sampling protocols have been employed by our group in order to determine the degree of enhancement of the four oxygenates in the valley air shed, as well as to determine their sources, emission profiles and emission rates (2). In 2008 and 2009, samples were in early summer, allowing us to compare the difference in concentration levels between both years.The photochemical production of ozone was calculated for each of the four oxygenates and approximately one hundred other quantified VOCs. Based on the Maximum Incremental Reactivity (MIR) scale and concentrations of each oxygenate in the atmosphere, for both 2008 and 2009, as much as 15% of O3 production in the valley is from ethanol and its photochemical by-product acetaldehyde. Our findings suggest that the data observed in 2008 is consistent with that observed in 2009, with a slight decrease in concentrations overall for 2009. 1. Lindberg, J. Analysis of the San Joaquin Valley 2007 Ozone Plan. State of California Air Resources Board. Final Draft Staff Report. 5/30/2007. 2. M. Yang, S. Meinardi, C. Krauter, D.R. Blake. Characterization of VOC Emissions from Various Components of Dairy Farming and their effect on San Joaquin Valley Air Quality. American Geophysical Union, Fall Meeting 2008, abstract #A53A-0241
ERIC Educational Resources Information Center
Jung, Steven M.; And Others
In an effort to encourage the participation of educationally disadvantaged youth in the Silicon Valley's high technology employment boom, the Peninsula Academies program was established utilizing a triad-partnership arrangement among the Sequoia Union High School District, high technology employers in the area, and the Stanford Mid-Peninsula Urban…
7. Photocopy of map of the Agua Fria Valley and ...
7. Photocopy of map of the Agua Fria Valley and lands to be irrigated by the Agua Fria Water and Land Company. Photographer Mark Durben, 1987 Source: 'Map of the Agua Fria Valley and the Western Portion of the Salt River Valley Showing the System of Reservoirs and Canals of the Agua Fria Water and Land Company and the Land to be Irrigated Thereby 160,000 Acres of New Land to be Reclaimed in the Maricopa County, Arizona Territory,' (Brochure) Union Photo Engraving Company, c. 1895, Salt River Project Research Archives, Tempe, Arizona. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ
Detail of lockers, shelving, etc. in art rooms and supply ...
Detail of lockers, shelving, etc. in art rooms and supply room. San Bernardino Valley Union Junior College, Classics Building. Lockers, bins, and cupboards-plans, elevations, sections. Howard E. Jones, Architect, San Bernardino, California. Sheet 7, job no. 312. Scale 1/2 inch to the foot. February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
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
Tychsen, Paul C.; Swenson, Herbert A.
1950-01-01
The Heart River irrigation project, in southwestern North Dakota, lies in the Missouri Plateau section of the Great Plains physiographic province, which extends from the Missouri escarpment to and beyond the western border of the State. The area ranges in altitude from 1,620 to 2,275 feet and locally has strong relief. The floor of the Heart River Valley is underlain by alluvial deposits of Quaternary age. In the westernmost part of the areas the Fort Union formation of Paleocene (Tertiary) age forms the valley sides, but in a downstream direction the Cannonball and Ludlow formations, here undifferentiated, also of Paleocene age, crop out in the valley sides and underlie progressively broader areas of the upland surface. The Hell Creek formation of Upper Cretaceous age appears above stream level only in the stretch of the valley between the center of T. 136 N., R. 85 W., and the northeastern part of T.. 137 N., R. 84 W. Glacial Drift, which once covered the whole area, now has been almost entirely removed by erosion except for .scattered boulders on the uplands. The Cannonball and Ludlow unit and the Fort Union formation yield, moderate supplies of ground water, and the river alluvium yields more abundant supplies. At the present rate of withdrawal and with normal precipitation there is little danger of seriously depleting the supply. In 1946 the average depth to water in observation wells in the Heart River Valley was 19 feet, whereas the depth to water in observation wells in the upland averaged 30 feet. The Dickinson area is small and is about 45 miles upstream from the Heart River irrigation project. Ground-water levels in the Dickinson municipal well field have declined considerably within recent years, but the impounding of Heart River water is expected to insure a more adequate water supply for the town. Samples of ground water from four wells in the lower Heart River Valley were analyzed to determine the present mineral character of the waters in this region. Waters from shallow and deep wells in the Dickinson area were analyzed to assist in determining the practicability of further utilization of ground water as a public supply. A map showing areas of the least-mineralized ground water in the Dickinson area is presented and the need of further exploratory work is discussed.
ERIC Educational Resources Information Center
Moraine Valley Community Coll., Palos Hills, IL.
The collective bargaining agreement between the Board of Community College District No. 524, County of Cook and State of Illinois, and the Moraine Valley Faculty Association is presented. This contract, covering the period from July 1, 1989 to June 30, 1992, deals with the following topics: definitions; bargaining agent recognition;…
Section AA through main entrance gates & west stairs. San ...
Section AA through main entrance gates & west stairs. San Bernardino Valley Union Junior College, Science Building. Also includes plans and sections of boys' and girls' toilets. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 311. Scales 1/4 inch to the foot (section AA) and 1/2 inch to the foot (toilet rooms). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
NASA Astrophysics Data System (ADS)
Vaudour, Emmanuelle; Carey, Victoria A.; Gilliot, Jean-Marc
2014-05-01
Geospatial technologies prove more and more useful for characterizing terroirs and this, not only at the within-field scale: amongst innovating technologies revolutionizing approaches for digitally zoning viticultural areas, be they managed by individual or cooperative grape growers, or even unions of grape growers, multispectral satellite remote sensing data have been used for 15 years already at either regional or whole-vineyard scale, starting from single date-studies to multi-temporal processings. Regional remotely-sensed approaches for terroir mapping mostly use multispectral satellite images in conjunction with a set of ancillary morphometric and/or geomorphological and/or legacy soil data and time series data on grape/wine quality and climate. Two prominent case-studies of regional terroir mapping using SPOT satellite images with medium spatial resolution (20 m) were carried out in the Southern Rhone Valley (Côtes-du-Rhône controlled Appelation of origin) in Southern France and in the Stellenbosch-Paarl region (including 5 Wine of Origin wards: Simonsberg-Stellenbosch, Simonsberg-Paarl, Jonkershoek Valley, Banghoek and Papegaaiberg and portions of two further wards, namely, Franschoek and Devon Valley) in the South Western Cape of South Africa. In addition to emphasizing their usefulness for operational land management, our objective was to develop, compare and discuss both approaches in terms of formalization, spatial data handling and processing, sampling design, validation procedures and/or availability of uncertainty information. Both approaches essentially relied on supervised image classifiers based on the selection of reference training areas. For the Southern Rhone valley, viticultural terroirs were validated using an external sample of 91 vineyards planted with Grenache Noir and Syrah for which grape composition was available over a large 17 years-period: the validation procedure highlighted a strong vintage effect for each specific terroir. The output map was appropriate at the scale of cooperative wineries and the scale of the union of grapegrowers. For the Stellenbosch-Paarl region, 55 Sauvignon Blanc vineyards previously characterized in terms of grape/vine/wine quality in several earlier studies were used to introduce expert knowledge as a basis for bootstrapped regression tree calculations, which enabled uncertainty assessment of final map results. Further perspectives related to the spatial monitoring of vine phenology according to the output terroir units and the possible characterization of both within/between terroir spatio-temporal variability of vegetative growth were initiated for the Southern Rhone terroirs considering a SPOT4-Take Five satellite time series acquired from February to June 2013 in the framework of the SPOT4-Take Five program of the French Space Agency (CNES).
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
Marshall, G.A.; Langbein, J.; Stein, R.S.; Lisowski, M.; Svarc, J.
1997-01-01
Five years of annual Global Positioning System (GPS) surveys of a network centered on Long Valley, California, constrain displacement rates for these stations relative to a central station in the network. These observations are consistent with recent models of resurgent dome inflation in Long Valley (Langbein et al., 1995) and have sufficient signal to detect the presence of Basin and Range strain in the Long Valley region. The data also allow for the possibility of dike inflation beneath the Mono Craters; dike intrusion is consistent with the Mono Craters' recent geologic history of ash eruptions, with seismic tomography, leveling data, and geologic studies of these volcanic domes and flows. Copyright 1997 by the American Geophysical Union.
Basal melting of snow on early Mars: A possible origin of some valley networks
Carr, M.H.; Head, J. W.
2003-01-01
Valley networks appear to be cut by liquid water, yet simulations suggest that early Mars could not have been warmed enough by a CO2-H2O greenhouse to permit rainfall. The vulnerability of an early atmosphere to impact erosion, the likely rapid scavenging of CO2 from the atmosphere by weathering, and the lack of detection of weathering products all support a cold early Mars. We explore the hypothesis that valley networks could have formed as a result of basal melting of thick snow and ice deposits. Depending on the heat flow, an early snowpack a few hundred meters to a few kilometers thick could undergo basal melting, providing water to cut valley networks. Copyright 2003 by the American Geophysical Union.
1981-10-01
Illinois River Valley, Illinois; the Jonesboro and Stuttgart regions of Arkansas; Union and Alexander Counties in southern Illinois; Reelfoot Lake and Lake ...food habits of mammals in the vicinity of Reelfoot Lake Biological Station, III. Discussion of the mammals recorded from the area. J. Tennessee Acad...Yeager and Anderson (1944) found that fox squir- rels were present in all timbered areas of a leveed bottomland lake in Illinois. Lowery (1974) stated
Remediation System Evaluation, A-Z Automotive in West Milford, New Jersey
The A-Z Automotive site is a former gasoline retail outlet and automobile service station located on Union Valley Road between St. George Street and Lou Ann Boulevard in West Milford, Passaic County, New Jersey.
Cannon, M.R.
1985-01-01
Otter Creek drains an area of 709 square miles in the coal-rich Powder River structural basin of southeastern Montana. The Knobloch coal beds in the Tongue River Member of the Paleocene Fort Union Formation is a shallow aquifer and a target for future surface mining in the downstream part of the Otter Creek basin. A mass-balance model was used to estimate the effects of potential mining on the dissolved solids concentration in Otter Creek and in the alluvial aquifer in the Otter Creek valley. With extensive mining of the Knobloch coal beds, the annual load of dissolved solids to Otter Creek at Ashland at median streamflow could increase by 2,873 tons, or a 32-percent increase compared to the annual pre-mining load. Increased monthly loads of Otter Creek, at the median streamflow, could range from 15 percent in February to 208 percent in August. The post-mining dissolved solids load to the subirrigated part of the alluvial valley could increase by 71 percent. The median dissolved solids concentration in the subirrigated part of the valley could be 4,430 milligrams per liter, compared to the pre-mining median concentration of 2,590 milligrams per liter. Post-mining loads from the potentially mined landscape were calculated using saturated-paste-extract data from 506 overburdened samples collected from 26 wells and test holes. Post-mining loads to the Otter Creek valley likely would continue at increased rates for hundreds of years after mining. If the actual area of Knobloch coal disturbed by mining were less than that used in the model, post-mining loads to the Otter Creek valley would be proportionally smaller. (USGS)
Section NN, showing steel roof trusses, mezzanine iron railing, first ...
Section NN, showing steel roof trusses, mezzanine iron railing, first floor doors, etc. San Bernardino Valley Union Junior College, Library Building. Also includes steel truss roof plan and a small stress diagram of the truss. Howard E. Jones, Architect, San Bernardino, California. Sheet 8, job no. 315. Scales 1/2 inch to the foot (section), and 1/8 and 1/16 inch to the foot. No date given on sheet (probably March or April, 1927). - San Bernardino Valley College, Library, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA
A Model of Cooperation: The VALNet Project.
ERIC Educational Resources Information Center
Oberg, Larry R.
1986-01-01
Description of VALNet (Valley Library Consortium), a consortium of public, academic, and school libraries in Idaho, highlights proposed online public access union catalog which would include nonbibliographic and referral files and circulation and serials control modules. The political climate, marketing, needs assessment, support and consultation,…
Bouri, M; Salghi, R; Bazzi, Lh; Zarrouk, A; Rios, A; Zougagh, M
2012-09-01
Dissipation of bifenthrin and λ-cyhalothrin pyrethroid insecticides, under environmental conditions, was evaluated on green beans grown in experimental greenhouses (Souss Massa valley, Morocco). Pesticide residues were determined by gas chromatography with micro electron-capture detector (GC-μECD) after dichloromethane extraction and cleanup on florisil phase cartridges. In the case of field experiments, a random block scheme was employed. Each block contained 25 plants in a single row and tests were carried out in triplicates applying pesticides at the recommended doses by the manufacturers. Fruit samples were periodically taken until the end of the preharvest interval (p.i.). The results obtained showed that the p.i of bifenthrin in green bean were 4 days in the winter and 3.5 days in the spring, whereas that for λ-cyhalothrin 8 days was found in the winter and 7.5 days in the spring. Consequently, it is possible to consider the European Union maximum residue limit (EU MRL) values compatible with the proper agricultural practices used for growing green bean in the plastic greenhouse of Souss Massa valley in South Morocco. Bifenthrin had a degradation of first-order kinetics, whereas that of levels for λ-cyhalothrin residue can not be interpreted by the use of a first order model.
Blackstone River Valley National Historical Park Establishment Act
Rep. Cicilline, David N. [D-RI-1
2013-02-14
House - 12/22/2014 Placed on the Union Calendar, Calendar No. 518. (All Actions) Notes: For further action, see H.R.3979, which became Public Law 113-291 on 12/19/2014. Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:
Geologic map of the Granite 7.5' quadrangle, Lake and Chaffee Counties, Colorado
Shroba, Ralph R.; Kellogg, Karl S.; Brandt, Theodore R.
2014-01-01
The geologic map of the Granite 7.5' quadrangle, Lake and Chaffee Counties, Colorado, portrays the geology in the upper Arkansas valley and along the lower flanks of the Sawatch Range and Mosquito Range near the town of Granite. The oldest rocks, exposed in the southern and eastern parts of the quadrangle, include gneiss and plutonic rocks of Paleoproterozoic age. These rocks are intruded by younger plutonic rocks of Mesoproterozoic age. Felsic hypabyssal dikes, plugs, and plutons, ranging in age from Late Cretaceous or Paleocene to late Oligocene, locally intruded Proterozoic rocks. A small andesite lava flow of upper Oligocene age overlies Paleoproterozoic rock, just south of the Twin Lakes Reservoir. Gravelly fluvial and fan deposits of the Miocene and lower Pliocene(?) Dry Union Formation are preserved in the post-30 Ma upper Arkansas valley graben, a northern extension of the Rio Grande rift. Mostly north-northwest-trending faults displace deposits of the Dry Union Formation and older rock units. Light detection and ranging (lidar) imagery suggests that two short faults, near the Arkansas River, may displace surficial deposits as young as middle Pleistocene. Surficial deposits of middle Pleistocene to Holocene age are widespread in the Granite quadrangle, particularly in the major valleys and on slopes underlain by the Dry Union Formation. The main deposits are glacial outwash and post-glacial alluvium; mass-movement deposits transported by creep, debris flow, landsliding, and rockfall; till deposited during the Pinedale, Bull Lake, and pre-Bull Lake glaciations; rock-glacier deposits; and placer-tailings deposits formed by hydraulic mining and other mining methods used to concentrate native gold. Hydrologic and geologic processes locally affect use of the land and locally may be of concern regarding the stability of buildings and infrastructure, chiefly in low-lying areas along and near stream channels and locally in areas of moderate to steep slopes. Low-lying areas along major and minor streams are subject to periodic stream flooding. Mass-movement deposits and deposits of the Dry Union Formation that underlie moderate to steep slopes are locally subject to creep, debris-flow deposition, and landsliding. Proterozoic rocks that underlie steep slopes are locally subject to rockfall. Sand and gravel resources for construction and other uses in and near the Granite quadrangle are present in outwash-terrace deposits of middle and late Pleistocene age along the Arkansas River and along tributary streams in glaciated valleys.
Dingman, Robert James; Gordon, Ellis D.; Swenson, H.A.
1954-01-01
The Fort Berthold Indian Reservation occupies about 1,000 square miles in west- central North Dakota. The Missouri and Little Missouri Rivers flow through the area and form part of its boundaries. Garrison Dam, which is under construction on the Missouri River 30 miles downstream from the east boundary of the reservation, will impound water in Garrison Reservoir and flood the valleys of both rivers throughout the area. The reservoir will divide the reservation into five parts, herein referred to as the eastern, northeastern, northern, western, and southern segments. Rock formations ranging in age from Paleocene to Recent are exposed. The Fort Union formation of Paleocene age underlies the entire reservation, and it crops out along the Missouri and Little Missouri Rivers. Relatively thin glacial till and outwash deposits of late Pleistocene age mantle much of the upland in all of the segments. The glacial de. posits commonly are less than 10 feet thick; in many places they consist only of scattered boulders on the bedrock surface. The major valleys have terrace deposits of Pleistocene and Recent age and alluvium of Recent age. The principal mineral resources of the reservation are lignite, sand, and gravel. The lignite beds range in thickness from a few inches to about 30 feet. At least four separate beds, which range in thickness from 4 feet to more than 7 feet, are mined locally. Although many mines will be flooded after Garrison Dam is completed, many suitable mine sites will remain above the proposed reservoir level. Sand and gravel deposits are found in glacial outwash and in stream-terrace deposits. On upland areas of the reservation ground water is available principally from the lignite and the associated fine- to medium-grained sandstone beds of the Fort Union formation. Few wells on the reservation are known to produce water from glacial material, although the recessional moraines are possible sources of shallow-water supplies. Small quantities of ground water are available from thin alluvial deposits in some places on the upland. Most wells in the valleys produce water from the alluvium or the terrace deposits. However, several wells penetrate the underlying Fort Union formation. A few flowing wells in the Missouri River valley near Elbowoods produce water from either the lower part of the Fort Union formation or from the Cannonball formation, also of Paleocene age. The chemical character of water from the Fort Union formation and the outwash and river gravels was determined from analyses of 39 samples from wells and springs. Water from bedrock may be either hard or soft, and it is moderately to highly mineralized. Water from the surficial deposits is uniformly hard, but it is less mineralized. Shallow wells in the eastern and northeastern segments produce water of good quality. Wells in these segments, and several springs in the western segment, could be used satisfactorily as domestic supplies. Spring water from lignite deposits on the reservation generally is colored and contains objectionable amounts of iron. Treatment of the water would improve its quality for domestic use. The filling of Garrison Reservoir will cause a rise of the water levels in wells that tap aquifers now discharging below the operating level of the reservoir. All the permeable strata below this level will become saturated, and ground-water bodies that are now separated will become hydraulically united. In addition to providing subsurface information, the drilling program of the U. S. Bureau of Indian Affairs provided wells for domestic and stock-water supplies. All test holes that tapped an adequate supply of potable water were reamed to a larger diameter, equipped with casing and well screen, and gravel-packed. The test-drilling program was completed in 1951; however, the drilling of domestic wells was continued under the supervision of the U. S. Geological Survey.
7 CFR 27.93 - Bona fide spot markets.
Code of Federal Regulations, 2012 CFR
2012-01-01
..., East Texas and Oklahoma, West Texas, Desert Southwest and San Joaquin Valley. Such markets will... Hidalgo counties. West Texas All Texas counties not included in the East Texas, Oklahoma and Desert Southwest Markets and the New Mexico counties of Union, Quay, Curry, Roosevelt and Lea. Desert Southwest The...
7 CFR 27.93 - Bona fide spot markets.
Code of Federal Regulations, 2013 CFR
2013-01-01
..., East Texas and Oklahoma, West Texas, Desert Southwest and San Joaquin Valley. Such markets will... Hidalgo counties. West Texas All Texas counties not included in the East Texas, Oklahoma and Desert Southwest Markets and the New Mexico counties of Union, Quay, Curry, Roosevelt and Lea. Desert Southwest The...
7 CFR 27.93 - Bona fide spot markets.
Code of Federal Regulations, 2011 CFR
2011-01-01
..., East Texas and Oklahoma, West Texas, Desert Southwest and San Joaquin Valley. Such markets will... Hidalgo counties. West Texas All Texas counties not included in the East Texas, Oklahoma and Desert Southwest Markets and the New Mexico counties of Union, Quay, Curry, Roosevelt and Lea. Desert Southwest The...
Building Robust Community Partnerships
ERIC Educational Resources Information Center
Walker, Diane L.
2012-01-01
The Antelope Valley Union High School District (AVUHSD), located in the Los Angeles, Bakersfield, and San Bernardino metro areas, receives students from eight area K-8 districts. AVUHSD is home to seven career academies with themes ranging from digital design and engineering to law and government, each of which integrates core content with…
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.
Courtside: "Ungodly" Agency Shop Fees Revisited
ERIC Educational Resources Information Center
Zirkel, Perry A.
2005-01-01
On 26 September 2001, the Chino Valley School District, which is approximately 30 miles east of Los Angeles, signed a negotiated agreement with the duly authorized union representing the certified employees, the Associated Chino Teachers (ACT). The agreement provided that every member of the represented unit would become either a member of the ACT…
Antarctic climate cooling and response of diatoms in glacial meltwater streams
Esposito, R.M.M.; Horn, S.L.; McKnight, Diane M.; Cox, M.J.; Grant, M.C.; Spaulding, S.A.; Doran, P.T.; Cozzetto, K.D.
2006-01-01
To understand biotic responses to an Antarctic cooling trend diatom samples from glacial meltwater streams in the McMurdo Dry Valleys, the largest ice-free area in Antarctica. Diatoms are abundant in these streams, and 24 of 40 species have only been found in the Antarctic. The percentage of these Antarctic diatom species increased with decreasing annual stream flow and increasing harshness of the stream habitat. The species diversity of assemblages reached a maximum when the Antarctic species accounted for 40-60% of relative diatom abundance. Decreased solar radiation and air-temperatures reduce annual stream flow, raising the dominance of these Antarctic species to levels above 60%. Thus, cooling favors the Antarctic species, and lowers diatom species diversity in this region. Copyright 2006 by the American Geophysical Union.
76 FR 12295 - James Luehman; Denial of Petition for Rulemaking
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-07
... retaliation for raising safety concerns. Union Electric Co. (Callaway Plant, Units 1&2), ALAB-527, 9 NRC 126... was decided by the Commission in the Tennessee Valley Authority (Watts Bar Nuclear Plant, Unit 1; Sequoyah Nuclear Plant, Units 1 and 2; Browns Ferry Nuclear Plant, Units 1, 2, and 3), CLI-04-24, 60 NRC...
Vaccines and Animal Models for Arboviral Encephalitides
2003-01-01
equine encephalitis Rodents Aedes, Culex mosquitoes and other species Central and South America, southern Florida IND Western equine encephalitis Birds...former Soviet Union Licensed Louping ill Birds Britain Murray Valley encephalitis Birds Culex mosquitoes Australia, New Guinea None Powassan Rodents ...Birds Culex mosquitoes North and South America None Tick-borne encephalitis Rodents Ixodes, Dermacentor, Haemaphysalis ticks Europe, Russia, former
New York Downtown Manhattan (Wall Street) Heliport - Operations Analysis
1991-09-01
Unicorn World Coord. E,NJ Stat Police G -Union Pacific ENorl Air- A Unisys ENVI Corp. E Universal Television ENY Helicopters A US Air Force M_NY Air E US...Yonkers construction E 4Phillip Morris E Phillips Aviation E Phipps E Pioneer Valley E Pitcairn Finance U PMC U PNN Helicopter U Prime Production E PSE&G
45. DETAIL ELEVATION OF STAMP BATTERIES AND APRONS, LOOKING SOUTHEAST. ...
45. DETAIL ELEVATION OF STAMP BATTERIES AND APRONS, LOOKING SOUTHEAST. MORTARS, BOSSES, MOST SHOES, STEMS, TAPPETS, CAMS AND BULL WHEELS ARE CLEARLY VISIBLE ON THE UPPER MORTAR BLOCKS (BELOW CENTER) UNION IRON WORKS, SAN FRANCISCO C-L. SEE CA-290-18 FOR A SIMILAR B&W NEGATIVE. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA
JPRS Report, Environmental Issues
1990-06-13
in settlements in valley locations, with the simultaneous application of efficient waste- gas purification proce- dures (dedusting, desulfurization ...Slaughtered [RUDE PRAVO 1 JunJ 17 Power Plant Desulfurization Technology, Funding Explored [ZEMEDELSKE NOVINY 29 Apr] . 17 GERMAN DEMOCRATIC...the Soviet Union, it is a question of money and a shortage of foreign currency but apparently also an attempt to develop its own pollution control
Rosen, Michael R.; Shaefer, Donald H.; Toccalino, Patricia A.; Delzer, Gregory C.
2006-01-01
As a part of the U.S. Geological Survey's National Water-Quality Assessment Program, an effort to characterize the quality of major rivers and aquifers used as a source of supply to some of the largest community water systems (CWSs) in the United States has been initiated. These studies, termed Source Water-Quality Assessments (SWQAs), consist of two sampling phases. Phase 1 was designed to determine the frequency of detection and concentrations of about 260 volatile organic compounds (VOCs), pesticides and pesticide degradates, and other anthropogenic organic compounds in source water of 15 CWS wells in each study. Phase 2 monitors concentrations in the source water and also the associated finished water of CWSs for compounds most frequently detected during phase 1. One SWQA was completed in the Nevada Basin and Range area in Nevada. Ten CWS wells in Eagle Valley and five CWS wells in Spanish Springs Valley were sampled. For phase 2, two wells were resampled in Eagle Valley. Samples were collected during 2002-2004 for both phases. Water use in Eagle Valley is primarily for domestic purposes and is supplied through CWSs. Ground-water sources provide about 55 percent of the public-water supply, and surface-water sources supply about 45 percent. Lesser amounts of water are provided by domestic wells. Very little water is used for agriculture or manufacturing. Spanish Springs Valley has water-use characteristics similar to those in Eagle Valley, although there is more agricultural water use in Spanish Springs Valley than in Eagle Valley. Maximum contaminant concentrations were compared to two human-health benchmarks, if available, to describe the water-quality data in a human-health context for these findings. Measured concentrations of regulated contaminants were compared to U.S. Environmental Protection Agency and Nevada Maximum Contaminant Level (MCL) values. Measured concentrations of unregulated contaminants were compared to Health-Based Screening Levels, which are not regulatory standards and are not legally enforceable values. All of the contaminants detected in this study were found at concentrations less than available human-health benchmarks. In the source waters sampled in phase 1, 10 contaminants of the approximately 260 measured were detected in samples collected from Eagle Valley, and 4 contaminants were detected in samples from Spanish Springs Valley. The most frequently detected compounds in the Eagle Valley source water were chloroform (a disinfection by-product), which was detected in samples from four wells, and deethylatrazine (a degradation product of the herbicide atrazine), which was detected in samples from three wells. Each of the four contaminants detected in the Spanish Springs Valley source waters was detected in samples from one well. The detection frequencies of VOCs and pesticides in samples from the SWQA wells were similar to those in samples from both shallow and deep monitoring wells in Carson City, Reno, and Spanish Springs. This indicates that the SWQA sampling is representative of the organic chemical compounds likely to be detected in the aquifers sampled. However, more organic compounds were detected at low frequencies and concentrations in samples from the monitoring wells than in samples from SWQA wells. Three contaminants were detected in one finished-water sample collected from Eagle Valley. Comparison of SWQA results in the Nevada Basin and Range Study Unit to results of an SWQA in the larger urban area of Salt Lake City showed that fewer anthropogenic compounds were detected in Eagle and Spanish Springs Valleys and generally at lower concentrations than in the Salt Lake City study.
A consortium of three brings real geothermal power for California's Imperial valley -- at last
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wehlage, E.F.
1983-04-01
Imperial Valley's geothermal history gets a whole new chapter with dedication ceremony for southern California's unusual 10,000 kilowatt power station-SCE in joint corporate venture with Southern Pacific and Union Oil. America's newest and unique electric power generation facility, The Salton Sea Geothermal-Electric Project, was the the site of a formal dedication ceremony while the sleek and stainless jacketed piping and machinery were displayed against a flawlessly brilliant January sky - blue and flecked with a few whisps of high white clouds, while plumes of geothermal steam rose across the desert. The occasion was the January 19, 1983, ceremonial dedication ofmore » the unique U.S.A. power generation facility constructed by an energy consortium under private enterprise, to make and deliver electricity, using geothermal steam released (with special cleaning and treatment) from magma-heated fluids produced at depths of 3,000 to 6,000 feet beneath the floor of the Imperial Valley near Niland and Brawley, California.« less
18. DETAIL ELEVATION OF STAMP BATTERIES AND APRONS, LOOKING SOUTHEAST. ...
18. DETAIL ELEVATION OF STAMP BATTERIES AND APRONS, LOOKING SOUTHEAST. MORTARS, BOSSES, MOST SHOES, STEMS, TAPPETS, CAMS AND BULL WHEELS ARE CLEARLY VISIBLE AND INTACT. NAMEPLATE CASTING IS CLEARLY VISIBLE ON THE UPPER MORTAR BLOCKS (BELOW CENTER) UNION IRON WORKS, SAN FRANCISCO C-L, SEE CA-290-45 (CT) FOR A SIMILAR COLOR TRANSPARENCY. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA
Outbreak of avian cholera on the wintering grounds of the Mississippi Valley Canada goose flock
Windingstad, R.M.; Duncan, R.M.; Thornburg, D.
1983-01-01
Avian cholera is reported for the first time in Canada geese, Branta canadensis, of the Mississippi Valley population. The disease was detected in weekly surveillance transects and was responsible for the loss of about 850 geese during the winter of 1978-1979 at localized areas in southern Illinois. Necropsies performed on 480 geese that died at Union County Conservation Area and on 133 birds at Horseshoe Lake Conservation Area during January and February 1979 revealed that the majority of losses (64%) were caused by avian cholera. Lead poisoning was responsible for the death of 14% of the geese analyzed and the remaining 22%, most of which were decomposed, were undiagnosed. Lethal lead levels and Pasteurella multocida occurred concomitantly in a few instances.
Kopczynski, S.E.; Ramage, J.; Lawson, D.; Goetz, S.; Evenson, E.; Denner, J.; Larson, G.
2008-01-01
We advance an approach to use satellite passive microwave observations to track valley glacier snowmelt and predict timing of spring snowmelt-induced floods at the terminus. Using 37 V GHz brightness temperatures (Tb) from the Special Sensor Microwave hnager (SSM/I), we monitor snowmelt onset when both Tb and the difference between the ascending and descending overpasses exceed fixed thresholds established for Matanuska Glacier. Melt is confirmed by ground-measured air temperature and snow-wetness, while glacier hydrologic responses are monitored by a stream gauge, suspended-sediment sensors and terminus ice velocity measurements. Accumulation area snowmelt timing is correlated (R2 = 0.61) to timing of the annual snowmelt flood peak and can be predicted within ??5 days. Copyright 2008 by the American Geophysical Union.
The February 21, 1993 tornadoes of East Tennessee
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fricke, K.E.; Kornegay, F.C.
1993-08-11
A series of tornadoes struck the east Tennessee area on Sunday afternoon, February 21, 1993 around Knoxville, Lenoir City, and Oak Ridge causing millions of dollars worth of damage to both homes and businesses in the area, killing one, injuring a number of persons, and leaving a large area without power for many hours or even days due to damage to the local TVA transmission line network. One tornado touched down in the Department of Energy Oak Ridge Reservation near the Oak Ridge Y-12 Plant, continued through the Union Valley business district located just east of the plant, through themore » adjacent University of Tennessee Arboretum and then continued into the communities of Claxton and Powell. The path length of the tornado was approximately 13 miles. Damage to the Y-12 Plant was minimal, but the Union Valley business district was seriously damaged, including the Fusion Energy Design Center (FEDC) which houses a number of DOE related projects. The preliminary cost estimate of the damage to DOE facilities (both at Y-12 and at the FEDC) was around $520,000. This paper describes the local meteorological data, the tornado that struck near the Y-12 plant, the resulting damage both to the DOE facilities and to the surrounding communities, the plant emergency response and recovery activities, and the current hazard analyses being undertaken at the plant.« less
Rare earth element content of thermal fluids from Surprise Valley, California
Andrew Fowler
2015-09-23
Rare earth element measurements for thermal fluids from Surprise Valley, California. Samples were collected in acid washed HDPE bottles and acidified with concentrated trace element clean (Fisher Scientific) nitric acid. Samples were pre-concentratated by a factor of approximately 10 using chelating resin with and IDA functional group and measured on magnetic sector ICP-MS. Samples include Seyferth Hot Springs, Surprise Valley Resort Mineral Well, Leonard's Hot Spring, and Lake City Mud Volcano Boiling Spring.
Panno, S.V.; Wiebel, C.P.; Heigold, P.C.; Reed, P.C.
1994-01-01
Three regolith-collapse sinkholes formed near the Dongola Unit School and the Pentecostal Church in the southern Illinois village of Dongola (Union County) during the spring of 1993. The sinkholes appeared over a three-month period that coincided with development of a new municipal well. The new well was drilled through clay-rich, valley-fill sediment into karstified limestone bedrock. The piezometric surface of the limestone aquifer is above land surface, indicating the presence of an upward hydraulic gradient in the valley and that the valley fill is acting as a confining unit. Pumping during development of the well lowered the piezometric surface of the limestone aquifer to an elevation below the base of the valley fill. It is hypothesized that drainage of water from the sediments, the resulting loss of hydrostatic pressure and buoyant force in overlying sediments, increased intergranular pressure, and the initiation of groundwater flow toward the well resulted in rapid sediment transport, subsurface erosion, and collapse of the valley-fill sediment. The sinkholes follow an approximately east-west alignment, which is consistent with one of the two dominant alignments of passages of nearby joint-controlled caves. A constant electrode-separation resistivity survey of the school playground was conducted to locate areas that might contain incipient sinkholes. The survey revealed a positive resistivity anomaly trending N75E in the southern part of the study area. The anomaly is linear, between 5 and 10 m wide, and its trend either intersects or is immediately adjacent to the three sinkholes. The anomaly is interpreted to be a series of pumping-induced cavities in the valley-fill sediments that formed over a preexisting crevice in the karstified bedrock limestone. ?? 1994 Springer-Verlag.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weibel, C.P.; Panno, S.V.; Heigold, P.C.
1994-04-01
Three regolith-collapse sinkholes formed near a school and a church in the southern Illinois village of Dongola (Union County) during the spring of 1993. The appearance of the sinkholes over a 3-month period coincided with development of a new municipal well, which was drilled through clay-rich, valley-fill sediment into karstified limestone bedrock. The piezometric surface of the limestone aquifer is above land surface, indicating an upward hydraulic gradient in the valley and that the valley-fill is acting as a confining unit. Pumping during development of the well lowered the piezometric surface of the limestone aquifer to an elevation below themore » base of the valley-fill. It is hypothesized that drainage of water from the sediments, the resulting loss of both hydrostatic pressure and buoyant force in overlying sediments, increased intergranular pressure, and the initiation of ground-water flow toward the well resulted in rapid sediment transport, subsurface erosion, and subsequent collapse of the valley-fill sediment. The sinkholes follow an approximately east-west alignment, which is consistent with one of the two dominant alignments of nearby joint-controlled caves. A constant electrode-separation resistivity survey of the school playground was conducted to locate areas that might contain incipient sinkholes. The survey revealed a linear, positive resistivity anomaly, between 5 and 10 m wide, and with a trend that either intersects or is immediately adjacent to the three sinkholes. The anomaly is interpreted to be a series of pumping-induced cavities in the valley-fill sediments that formed over a pre-existing crevice in the karstified bedrock limestone.« less
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.
Geology of the Knife River area, North Dakota
Benson, William Edward
1953-01-01
The Knife River area, consisting of six 15-minute quadrangles, includes the lower half of the Knife River valley in west-central North Dakota. The area, in the center of the Williston Basin, is underlain by the Tongue River member of the Fort Union formation (Paleocene) and the Golden Valley formation (Eocene). The Tongue River includes beds equivalent to the Sentinel Butte shale; the Golden Valley formation, which receives its first detailed description in this report, consists of two members, a lower member of gray to white sandy kaolin clay and an upper member of cross-bedded micaceous sandstone. Pro-Tongue River rocks that crop out in southwestern North Dakota include the Ludlow member of the Fort Union formation, the Cannonball marine formation (Paleocene) and the Hell Creek, Fox Hills, and Pierre formations, all upper Cretaceous. Post-Golden Valley rocks include the White River formation (Oligocene) and gravels on an old planation surface that may be Miocene or Pliocent. Surficial deposits include glacial and fluvial deposits of Pleistocene age and alluvium, dune sand, residual silica, and landslide blocks of Recent age. Three ages of glacial deposits can be differentiated, largely on the basis of three fills, separated by unconformities, in the Knife River valley. All three are of Wisconsin age and probably represent the Iowan, Tazewell, and Mankato substages. Deposits of the Cary substage have not been identified either in the Knife River area or elsewhere in southern North Dakota. Iowan glacial deposits form the outermost drift border in North Dakota. Southwest of this border are a few scattered granite boulders that are residual from the erosion of either the White River formation or a pre-Wisconsin till. The Tazewell drift border cannot be followed in southern North Dakota. The Mankato drift border can be traced in a general way from the South Dakota State line northwest across the Missouri River and through the middle of the Knife River area. The major land forms of southwestern North Dakota are: (1) high buttes that stand above (2) a gravel-capped planation surface and (3) a gently-rolling upland; below the upland surface are (4) remnants of a broad valley stage of erosion into which (5) modern valleys have been cut. The broad valley profiles of many streams continue east across the Missouri River trench and are part of a former drainage system that flowed into Hudson Bay. Crossing the divides are (6) large trenches, formed when the former northeast-flowing streams were dammed by the glacier and diverted to the southeast. The largest diversion valley is occupied by the Missouri River; another diversion system, now largely abandoned, extends from the Killdeer Mountains southwest to the mouth of Porcupine Creek in Sioux County. By analogy with South Dakota, most of the large diversion valleys are thought to have been cut in Illinoian time. Numerous diversion valleys of Illinoian to late Wisconsin age cut across the divides. Other Pleistocene land forms include ground and moraines, kames, and terraces. Land forms of Recent age include dunes, alluvial terraces, floodplains, and several types of landslide blocks. One type of landslide, called rockslide slump, has not previously been described. Drainage is well adjusted to the structure, most of the streams flowing down the axes of small synclines. The bedrock formations have been gently folded into small domes and synclines that interrupt a gentle northward regional dip into the Williston Basin. Three episodes of deformation affected southwestern North Dakota in Tertiary time: (1) intra-Paleocene, involving warping and minor faulting; (2) post-Eocene, involving uplift and tilting; (2) Oligocene, involving uplift and gentle folding. Mineral resources include ceramic clay, sand and gravel and lignite coal. The Knife River area is the largest lignite-producing district in the United States.
2008-04-01
well trained and educated for employment in all forms ofwarfare."z After years ofpreparing for 1 L I conventional war on the presumption superior...far. He sent two ofhis best Rangers, John Puryear and Charley McDough, back to Kabletown with orders to keep an eye out for any signs of Blazer and...military education , Captain Blazer was unbound from the restraints and constraints of conventional military science and allowed to apply the true art
Miller, Todd S.
2009-01-01
In 2002, the U.S. Geological Survey, in cooperation with the Town of Caroline and Tompkins County Planning Department, began a study of the valley-fill aquifer system in upper Sixmile Creek and headwaters of West Branch Owego Creek valleys in the Town of Caroline, NY. The purpose of the study is to provide geohydrologic data to county and town planners as they develop a strategy to manage and protect their water resources. The first aquifer reach investigated in this series is in the Town of Caroline and includes the upper Sixmile Creek valley and part of West Branch Owego Creek valley. The portions of the valley-fill aquifer system that are comprised of saturated coarse-grained sediments including medium to coarse sand and sandy gravel form the major aquifers. Confined sand and gravel units form the major aquifers in the western and central portions of the upper Sixmile Creek valley, and an unconfined sand and gravel unit forms the major aquifer in the eastern portion of the upper Sixmile Creek valley and in the headwaters of the West Branch Owego Creek valley. The valley-fill deposits are thinnest near the edges of the valley where they pinch out along the till-mantled bedrock valley walls. The thickness of the valley fill in the deepest part of the valley, at the western end of the study area, is about 100 feet (ft); the thickness is greater than 165 ft on top of the Valley Heads Moraine in the central part of the valley. An estimated 750 people live over and rely on groundwater from the valley-fill aquifers in upper Sixmile Creek and West Branch Owego Creek valleys. Most groundwater withdrawn from the valley-fill aquifers is pumped from wells with open-ended 6-inch diameter casings; the remaining withdrawals are from shallow dug wells or cisterns that collect groundwater that discharges to springs (especially in the Brooktondale area). The valley-fill aquifers are the sources of water for about 200 households, several apartment complexes, two mobile home parks, a school, and several farms and small businesses. Most groundwater that is withdrawn from pumped wells is returned to the groundwater system via septic systems. Groundwater in the upper and basal confined aquifers in the upper Sixmile Creek valley is under artesian conditions everywhere except where the water discharges to springs along bluffs in the western end of the Sixmile Creek valley. Principal sources of recharge to the confined aquifers are (1) the sides of the valley where the confined aquifers may extend up along the flank of the bedrock valley wall and crop out at land surface or are overlain and in contact with surficial coarse-grained deltaic and fluvial sediments that provide a pathway through which direct precipitation and seepage losses from tributary streams can reach the buried aquifers, or (2) where the buried aquifers are isolated and receive recharge only from adjacent fine-grained sediment and bedrock. The base-flow and runoff components of total streamflow at two streamgages, Sixmile Creek at Brooktondale and Sixmile Creek at Bethel Grove, were calculated using hydrograph-separation techniques from 2003 to 2007 discharge records. Base flow constituted 64 and 56 percent of the total annual flow at the Brooktondale and Bethel Grove streamgages, respectively. Water-quality samples were collected from 2003 to 2005, with 10 surface-water samples collected seasonally during base-flow conditions at the Sixmile Creek at Brooktondale streamgage, and 12 samples were collected during base-flow conditions at several selected tributaries from 2004 to 2005. The predominant cation detected in the surface-water samples was calcium, but moderate amounts of magnesium, silica, and sodium were also detected; the major anions were bicarbonate, chloride, and sulfate. Sodium and chloride concentrations were relatively low in all samples but increased downstream from the Sixmile Creek sampling site at Six Hundred Road near Slaterville Springs, NY, to B
NASA Astrophysics Data System (ADS)
Zacny, K.; Paulsen, G.; McKay, C.; Glass, B. J.; Marinova, M.; Davila, A. F.; Pollard, W. H.; Jackson, A.
2011-12-01
We report on the testing of the one meter class prototype Mars drill and cuttings sampling system, called the IceBreaker in the Dry Valleys of Antarctica. The drill consists of a rotary-percussive drill head, a sampling auger with a bit at the end having an integrated temperature sensor, a Z-stage for advancing the auger into the ground, and a sampling station for moving the augered ice shavings or soil cuttings into a sample cup. In November/December of 2010, the IceBreaker drill was tested in the Uni-versity Valley (within the Beacon Valley region of the Antarctic Dry Valleys). University Valley is a good analog to the Northern Polar Regions of Mars because a layer of dry soil lies on top of either ice-cemeted ground or massive ice (depending on the location within the valley). That is exactly what the 2007 Phoenix mission discovered on Mars. The drill demonstrated drilling in ice-cemented ground and in massive ice at the 1-1-100-100 level; that is the drill reached 1 meter in 1 hour with 100 Watts of power and 100 Newton Weight on Bit. This corresponds to an average energy of 100 Whr. At the same time, the bit temperature measured by the bit thermocouple did not exceed more than 10 °C above the formation temperature. The temperature also never exceeded freezing, which minimizes chances of getting stuck and also of altering the materials that are being sampled and analyzed. The samples in the forms of cuttings were acquired every 10 cm intervals into sterile bags. These tests have shown that drilling on Mars, in ice cemented ground with limited power, energy and Weight on Bit, and collecting samples in discrete depth intervals is possible within the given mass, power, and energy levels of a Phoenix-size lander and within the duration of a Phoenix-like mission.
Hodgkinson, K.M.; Stein, R.S.; King, G.C.P.
1996-01-01
In 1954, four earthquakes of M > 6.0 occurred within a 30 km radius in a period of six months. The Rainbow Mountain-Fairview Peak-Dixie Valley earthquakes are among the largest to have been recorded geodetically in the Basin and Range province. The Fairview Peak earthquake (M=7.2, December 12, 1954) followed two events in the Rainbow Mountains (M=6.2, July 6, and M=6.5, August 24, 1954) by 6 months. Four minutes later the Dixie Valley fault ruptured (M=6.7, December 12, 1954). The changes in static stresses caused by the events are calculated using the Coulomb-Navier failure criterion and assuming uniform slip on rectangular dislocations embedded in an elastic half-space. Coulomb stress changes are resolved on optimally oriented faults and on each of the faults that ruptured in the chain of events. These calculations show that each earthquake in the Rainbow Mountain-Fairview Peak-Dixie Valley sequence was preceded by a static stress change that encouraged failure. The magnitude of the stress increases transferred from one earthquake to another ranged from 0.01 MPa (0.1 bar) to over 0.1 MPa (1 bar). Stresses were reduced by up to 0.1 MPa over most of the Rainbow Mountain-Fairview Peak area as a result of the earthquake sequence. Copyright 1996 by the American Geophysical Union.
Oberlin, Elizabeth A; Claire, Mark W; Kounaves, Samuel P
2018-02-09
Locations on Earth that provide insights into processes that may be occurring or may have occurred throughout martian history are often broadly deemed "Mars analog environments." As no single locale can precisely represent a past or present martian environment, it is important to focus on characterization of terrestrial processes that produce analogous features to those observed in specific regions of Mars or, if possible, specific time periods during martian history. Here, we report on the preservation of ionic species in soil samples collected from the Tindouf region of Morocco and compare them with the McMurdo Dry Valleys of Antarctica, the Atacama Desert in Chile, the martian meteorite EETA79001, and the in situ Mars analyses from the Phoenix Wet Chemistry Laboratory (WCL). The Moroccan samples show the greatest similarity with those from Victoria Valley, Beacon Valley, and the Atacama, while being consistently depleted compared to University Valley and enriched compared to Taylor Valley. The NO 3 /Cl ratios are most similar to Victoria Valley and Atacama, while the SO 4 /Cl ratios are similar to those from Beacon Valley, Victoria Valley, and the Atacama. While perchlorate concentrations in the Moroccan samples are typically lower than those found in samples of other analog sites, conditions in the region are sufficiently arid to retain oxychlorines at detectable levels. Our results suggest that the Tindouf Basin in Morocco can serve as a suitable analogue for the soil geochemistry and subsequent aridification of the Noachian epoch on Mars. Key Words: Mars analogues-Antarctica-Morocco-Oxyanions-Perchlorate-Nitrate. Astrobiology 18, xxx-xxx.
NASA Astrophysics Data System (ADS)
Blake, D. R.; Yang, M.; Meinardi, S.; Krauter, C.; Rowland, F. S.
2009-05-01
The San Joaquin Valley Air Pollution Control District of California issued a report identifying dairies as a main source of Volatile Organic Compounds (VOCs). A dairy study funded by the California Air Resources Board commenced shortly after the report was issued. Our University of California Irvine group teamed with California State University Fresno to determine the major sources of VOCs from various dairy operations and from a variety of dairy types. This study identified ethanol and methanol as two gases produced in major quantities throughout the dairies in the San Joaquin valley as by-products of yeast fermentation of silage. Three different types of sampling protocols were employed in order to determine the degree of enhancement of the target oxygenates in the valley air shed. Their sources, emission profiles, and emission rates were determined from whole air samples collected at various locations at the six dairies studied. An assessment of the impact of dairy emissions in the valley was achieved by using data obtained on low altitude NASA DC-8 flights through the valley, and from ground level samples collected though out the valley in a grid like design. Our data suggest that a significant amount of O3 production in the valley may come from methanol, ethanol, and acetaldehyde (a photochemical by-product ethanol oxidation). Our findings indicate that improvement to valley air quality may be obtained by focusing on instituting new silage containment practices and regulations.
Geology and mineral resources of the Mud Springs Ranch Quadrangle, Sweetwater County, Wyoming
Roehler, Henry W.
1979-01-01
The Mud Springs Ranch quadrangle occupies an area of 56 mF (square miles) on the southeast flank of the Rock Springs uplift in southwestern Wyoming. The climate is arid and windy. The landscape is mostly poorly vegetated and consists of north-trending ridges and valleys that are dissected by dry drainages. Sedimentary rocks exposed in the quadrangle are 5,400 ft (feet) thick and are mostly gray sandstone, siltstone, and shale, gray and brown carbonaceous shale, and thin beds of coal. They compose the Blair, Rock Springs, Ericson, Almond, and Lewis Formations of Cretaceous age and the Fort Union Formation of Paleocene age. The structure is mostly homoclinal, having southeast dips of 5?-12? in the northern part of the quadrangle, but minor plunging folds and one small fault are present in the southern part of the quadrangle. Three coal beds in the Fort Union Formation and 15 coal beds in the Almond Formation exceed 2.5 ft in thickness, are under less than 3,000 ft of overburden, and are potentially minable. Geographic stratigraphic, and resource data are present for each bed of minable coal. The total minable coal resources are estimated to be about 283 million short tons. Nine coal and rock samples from outcrops were analyzed to determine their quality and chemical composition. Four dry oil and gas test wells have been drilled within the quadrangle area, but structurally controlled stratigraphic-trap prospects remain untested.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coplen, T.B.
1973-10-01
Preliminary studies indicate that the Imperial Valley has a large geothermal potential. In order to delineate additional geothermal systems a chemical and isotopic investigation of samples from water wells, springs, and geothermal wells in the Imperial Valley and Yuma areas was conducted. Na, K, and Ca concentrations of nearly 200 well water, spring water, hot spring, and geothermal fluid samples from the Imperial Valley area were measured by atomic absorption spectrophotometry. Fournier and Truesdell's function was determined for each water sample. Suspected geothermal areas are identified. Hydrogen and oxygen isotope abundances were determined in order to determine and to identifymore » the source of the water in the Mesa geothermal system. (JGB)« less
NASA Astrophysics Data System (ADS)
Stang, Dallon Michael
Petrographic, conglomerate and detrital-zircon analyses of formations in southern California can determine consanguineous petrofacies and lithofacies that help constrain paleotectonic and paleogeographic reconstructions of the southwestern United States. Arkosic sandstone of the lower Middle Miocene Cajon Valley formation is exposed on the southwest edge of the Mojave block and juxtaposed against Mesozoic and Paleozoic rocks by the San Andreas fault (SAf). Early work in Cajon Valley referred to the formation as Punchbowl, due to its similar appearance to the Punchbowl Formation at Devil's Punchbowl (northwest along the SAf). However, paleontological work placed Cajon Valley strata in the Hemingfordian-Barstovian (18-14 Ma), as opposed to the Clarendonian-Hemphillian (13-9 Ma) Punchbowl Formation. Since the Cajon Valley formation was deposited prior to being truncated by the San Andreas fault, the 2400m-thick, laterally extensive subaerial deposits likely were deposited across what is now the fault trace. Restoring 310 km of dextral slip on the SAf system should indicate the location of offset equivalent sandstone. Restoration of slip on the SAf system places Cajon Valley adjacent to the Caliente and La Panza Ranges, east of San Luis Obispo. Although analysis of detrital zircon from Cenozoic sandstone throughout southern California has been crucial in establishing paleodrainage areas, detrital zircon from the Cajon Valley and equivalent formations had not been analyzed prior to this study. Paleocurrents measured throughout the Cajon Valley formation indicate a source to the NE, in the Mojave Desert. Sandstone samples analyzed in thin section using the Gazzi-Dickinson method of point-counting are homogeneously arkosic, with slight compositional variability, making differentiation of the Cajon Valley formation and potential offset equivalents problematic. However, Branch Canyon Sandstone and Santa Margarita Formation samples are compositionally the best match for the Cajon Valley formation. Detrital-zircon ages were determined from the Cajon Valley formation and related strata. These data are slightly more variable than sandstone composition, with distinct age peaks at 85-90 Ma, 150 Ma and 250 Ma. These ages correlate with batholiths in the SW Mojave Desert. Of the nine samples from six formations collected as potential offset equivalents, Branch Canyon and Santa Margarita samples are most similar to Cajon Valley samples, in terms of both detrital-zircon ages and sandstone composition. Based on 310km of post-Miocene offset on the San Andreas fault system, the Cajon Valley formation restores adjacent to shallow-marine sandstone of the Santa Margarita Formation and Branch Canyon Sandstone Member of the Monterey Formation in the Caliente and La Panza ranges. Cajon Valley sandstone is interpreted to represent a Miocene fluvial system on a coastal plain, flowing toward a delta on a narrow continental shelf.
Publications - GMC 331 | Alaska Division of Geological & Geophysical
DGGS GMC 331 Publication Details Title: Coal vitrinite analysis of Copper Valley well samples as , Terry, 2006, Coal vitrinite analysis of Copper Valley well samples as follows: UNOCAL Tazlina #1
Code of Federal Regulations, 2010 CFR
2010-07-01
... Unions Certificate of Compliance C Appendix C to Part 231 National Defense Department of Defense... UNIONS AND OTHER FINANCIAL INSTITUTIONS ON DOD INSTALLATIONS Pt. 231, App. C Appendix C to Part 231... union complies with the requirements of section 170 of the Federal Credit Union Act (12 U.S.C 1770), for...
Determination of water-soluble ions in soils from the dry valleys of Antarctica
NASA Technical Reports Server (NTRS)
Bustin, R.
1981-01-01
The soil chemistry of the dry valleys of Antarctica was studied. These valleys furnish a terrestrial analog for the surface of Mars. The abundance of the water-soluble ions magnesium, calcium, potassium, sodium chloride, and nitrate in soil samples was determined. All samples examined contained water-soluble salts reflecting the aridity of the area. Movement of salts to low-lying areas was verified. Upward ionic migration was evident in all core samples. Of all cations observed, sodium showed the greatest degree of migration.
2012-2013 Delaware Valley Household Travel Survey | Transportation Secure
Data Center | NREL 12-2013 Delaware Valley Household Travel Survey 2012-2013 Delaware Valley Household Travel Survey The 2012-2013 Delaware Valley Household Travel Survey collected data for multiple ) sponsored the survey in collaboration with AbtSRBI. Methodology A sampling strategy was designed to recruit
Observation of valley-selective microwave transport in photonic crystals
NASA Astrophysics Data System (ADS)
Ye, Liping; Yang, Yuting; Hong Hang, Zhi; Qiu, Chunyin; Liu, Zhengyou
2017-12-01
Recently, the discrete valley degree of freedom has attracted extensive attention in condensed matter physics. Here, we present an experimental observation of the intriguing valley transport for microwaves in photonic crystals, including the bulk valley transport and the valley-projected edge modes along the interface separating different photonic insulating phases. For both cases, valley-selective excitations are realized by a point-like chiral source located at proper locations inside the samples. Our results are promising for exploring unprecedented routes to manipulate microwaves.
Healy, D.F.
1996-01-01
The Rio Grande Valley study unit of the U.S. Geological Survey National Water-Quality Assessment Program conducted a two-phase synoptic study of the occurrence and distribution of pesticides and nutrients in the surface water of the Mesilla Valley, New Mexico and Texas. Phase one, conducted in April-May 1994 during the high-flow irrigation season, consisted of a 6-week time- series sampling event during which 17 water-column samples were collected at 3 main-stem sites on the Rio Grande and a synoptic irrigation-run sampling event during which 19 water-column samples were collected at 7 main-stem sites, 10 drain sites, and 2 sites at the discharges of wastewater-treatment plants. Three samples are included in both the time-series and irrigation-run events. Phase two, conducted in January 1995 during the low-flow non-irrigation season, consisted of a non-irrigation synoptic sampling event during which 18 water-column samples were collected at seven main-stem sites, nine drain sites, and two sites at the discharges of wastewater-treatment plants and a bed- material sampling event during which 6 bed-material samples were collected at six sites near the mouths of drains that discharge to the Rio Grande. The 51 water-column samples were analyzed for 78 pesticides and metabolites and 8 nutrients along with other constituents. The six bed-material samples were analyzed for 21 pesticides and metabolites, gross polychlorinated biphenyls, and gross polychlorinated naphthalenes. The presence of dissolved pesticides in the surface water of the Mesilla Valley is erratic. A total of 100 detections of 17 different pesticides were detected in 44 of the water-column samples. As many as 38 percent of these detections may be attributed to pesticide use upstream from the valley or to nonagricultural pesticide use within the valley. There were 29 detections of 10 different pesticides in 17 samples during the irrigation run and 41 detections of 13 pesticides in 16 samples during the non-irrigation run. Nine pesticides were detected during both phases of the study. The most commonly detected pesticides in the water-column samples were DCPA, which was detected in 29 samples, and metolachlor, which was detected in 17 of the samples. DCPA was detected throughout the Mesilla Valley, whereas metolachlor was detected mainly in the northern and central parts of the valley. The maximum pesticide concentration found during the study was 0.75 microgram per liter of carbofuran, which was detected at the East Side Drain site during the irrigation run. No water-column pesticide concentration exceeded U.S. Environmental Protection Agency's drinking-water standards or any applicable Federal or State criteria or guidelines. A total of 21 occurrences of six pesticides and metabolites were found in the bed-material samples. Chlordane, diazinon, and methyl parathion were detected once each, whereas DDD, DDE, and DDT were detected at all six bed-material sites. Water-column samples for the analysis of nutrient concentrations were collected at all sampling sites during both phases of the study. The concentrations of each nutrient ranged from at or below the individual minimum reporting level to as much as two or three orders of magnitude larger than the minimum reporting level. The concentration of each nutrient was left skewed with most of the values toward the lower end of the range. The larger concentrations of each nutrient, except dissolved nitrite plus nitrate, were associated with wastewater-treatment- plant sites 4 and 16. The larger concentrations of dissolved nitrite plus nitrate were generally associated with the non- irrigation run; however, the largest concentration was at site 4 during the irrigation run. During this study, the Mesilla Valley as a unit was a source of nutrients to the Rio Grande. Wi
Anderholm, S.K.
1996-01-01
This report describes the quality of shallow ground water in an agricultural area in the San Luis Valley, Colorado, and discusses how natural and human factors affect the quality of shallow ground water. Thirty-five wells were installed, and water samples were collected from these wells and analyzed for selected dissolved common constituents, nutrients, trace elements, radionuclides, and synthetic organic compounds. The San Luis Valley is a high intermontane valley that is partially drained by the Rio Grande. The San Luis Valley land-use study area was limited to a part of the valley where the depth to water is generally less than 25 feet. The area where the 35 monitor wells were installed was further limited to the part of the study area where center-pivot overhead sprinklers are used to irrigate crops. Precipitation, runoff from adjacent mountainous areas, and ground-water inflow from the adjacent mountainous areas are the main sources of water to the aquifers in the San Luis Valley. Discharge of water from the shallow, unconfined aquifer in the valley is mainly from evapotranspiration. The dominant land use in the San Luis Valley is agriculture, although nonirrigated land and residential land are interspersed with agricultural land. Alfalfa, native hay, barley, wheat, potatoes, and other vegetables are the main crops. Dissolved-solids concentrations in shallow ground water sampled ranged from 75 to 1,960 milligrams per liter. The largest median concentration of cations was for calcium, and the largest median concentration of anions was for bicarbonate in shallow ground water in the San Luis Valley. Calcium concentrations ranged from 7.5 to 300 milligrams per liter, and bicarbonate concentrations ranged from 28 to 451 milligrams per liter. Nitrite plus nitrate concentrations ranged from less than 0.1 to 58 milligrams per liter as N; water from 11 wells had nitrite plus nitrate concentrations greater than 10 milligrams per liter as N. With the exception of the following trace elements--aluminum, barium, iron, manganese, molybdenum, and uranium--the concentrations of trace elements were less than 10 micrograms per liter in 90 percent of the samples. All trace-element concentrations measured were below the maximum contaminant levels set by the U.S. Environmental Protection Agency. Five samples exceeded the proposed maximum contaminant level of 0.02 milligram per liter for uranium. All samples collected exceeded the proposed maximum contaminant level for radon-222. The volatile organic compound methyltertbutylether was detected in one sample at a concentration of 0.6 microgram per liter. Of the pesticides analyzed for, one or more were detected in water from 5 of the 35 wells sampled. Metribuzin was the most commonly detected pesticide and was detected in water from three wells at concentrations ranging from an estimated 0.005 to 0.017 microgram per liter. Metolachlor (detected in one sample at a concentration of 0.072 microgram per liter), prometon (detected in one sample at a concentration of 0.01 microgram per liter), and p,p'-DDE (detected in one sample at an estimated concentration of 0.002 microgram per liter) were the other pesticides detected. The U.S. Environmental Protection Agency lifetime health advisory for metolachlor, metribuzin, and prometon is 100 micrograms per liter, which is much larger than the concentrations measured in the shallow ground water sampled for this study. The elevated nitrite plus nitrate concentrations in shallow ground water are indicative of leaching of fertilizers from the land surface. This conclusion is consistent with conclusions made in other investigations of the San Luis Valley. On the basis of areal distribution and range of trace-element concentrations, human activities have not caused widespread trace-element contamination in the shallow grou
Berger, David L.; Maurer, Douglas K.; Lopes, Thomas J.; Halford, Keith J.
2004-01-01
The Dry Valley Hydrographic Area is being considered as a potential source area for additional water supplies for the Reno-Sparks area, which is about 25 miles south of Dry Valley. Current estimates of annual ground-water recharge to Dry Valley have a considerable range. In undeveloped valleys, such as Dry Valley, long-term ground-water discharge can be assumed the same as long-term ground-water recharge. Because estimating ground-water discharge has more certainty than estimating ground-water recharge from precipitation, the U.S. Geological Survey, in cooperation with Washoe County, began a three-year study to re-evaluate the ground-water resources by estimating natural ground-water discharge and characterize ground-water quality in Dry Valley. In Dry Valley, natural ground-water discharge occurs as subsurface outflow and by ground-water evapotranspiration. The amount of subsurface outflow from the upper part of Dry Valley to Winnemucca and Honey Lake Valleys likely is small. Subsurface outflow from Dry Valley westward to Long Valley, California was estimated using Darcy's Law. Analysis of two aquifer tests show the transmissivity of poorly sorted sediments near the western side of Dry Valley is 1,200 to 1,500 square feet per day. The width of unconsolidated sediments is about 4,000 feet between exposures of tuffaceous deposits along the State line, and decreases to about 1,500 feet (0.5 mile) west of the State line. The hydraulic gradient east and west of the State line ranges from 0.003 to 0.005 foot per foot. Using these values, subsurface outflow to Long Valley is estimated to be 50 to 250 acre-feet per year. Areas of ground-water evapotranspiration were field mapped and partitioned into zones of plant cover using relations derived from Landsat imagery acquired July 8, 2002. Evapotranspiration rates for each plant-cover zone were multiplied by the corresponding area and summed to estimate annual ground-water evapotranspiration. About 640 to 790 acre-feet per year of ground water is lost to evapotranspiration in Dry Valley. Combining subsurface-outflow estimates with ground-water evapotranspiration estimates, total natural ground-water discharge from Dry Valley ranges from a minimum of about 700 acre-feet to a maximum of about 1,000 acre-feet annually. Water quality in Dry Valley generally is good and primary drinking-water standards were not exceeded in any samples collected. The secondary standard for manganese was exceeded in three ground-water samples. One spring sample and two surface-water samples exceeded the secondary standard for pH. Dry Valley has two primary types of water chemistry that are distinguishable by cation ratios and related to the two volcanic-rock units that make up much of the surrounding mountains. In addition, two secondary types of water chemistry appear to have evolved by evaporation of the primary water types. Ground water near the State line appears to be an equal mixture of the two primary water chemistries and has as an isotopic characteristic similar to evaporated surface water.
Water resources of Parowan Valley, Iron County, Utah
Marston, Thomas M.
2017-08-29
Parowan Valley, in Iron County, Utah, covers about 160 square miles west of the Red Cliffs and includes the towns of Parowan, Paragonah, and Summit. The valley is a structural depression formed by northwest-trending faults and is, essentially, a closed surface-water basin although a small part of the valley at the southwestern end drains into the adjacent Cedar Valley. Groundwater occurs in and has been developed mainly from the unconsolidated basin-fill aquifer. Long-term downward trends in groundwater levels have been documented by the U.S. Geological Survey (USGS) since the mid-1950s. The water resources of Parowan Valley were assessed during 2012 to 2014 with an emphasis on refining the understanding of the groundwater and surface-water systems and updating the groundwater budget.Surface-water discharge of five perennial mountain streams that enter Parowan Valley was measured from 2013 to 2014. The total annual surface-water discharge of the five streams during 2013 to 2014 was about 18,000 acre-feet (acre-ft) compared to the average annual streamflow of about 22,000 acre-ft from USGS streamgages operated on the three largest of these streams from the 1940s to the 1980s. The largest stream, Parowan Creek, contributes more than 50 percent of the annual surface-water discharge to the valley, with smaller amounts contributed by Red, Summit, Little, and Cottonwood Creeks.Average annual recharge to the Parowan Valley groundwater system was estimated to be about 25,000 acre-ft from 1994 to 2013. Nearly all recharge occurs as direct infiltration of snowmelt and rainfall on the Markagunt Plateau east of the valley. Smaller amounts of recharge occur as infiltration of streamflow and unconsumed irrigation water near the east side of the valley on alluvial fans associated with mountain streams at the foot of the Red Cliffs. Subsurface flow from the mountain block to the east of the valley is a significant source of groundwater recharge to the basin-fill aquifer. Groundwater flows from the high-altitude recharge areas downward toward the basin-fill aquifer in Parowan Valley. Almost all groundwater discharge occurs as withdrawals from irrigation wells in the valley with a small amount of discharge from phreatophytic evapotranspiration. Subsurface groundwater discharge to Cedar Valley is likely minimal. Withdrawals from wells during 2013 were about 32,000 acre-ft. The estimated withdrawals from wells from 1994 to 2013 have ranged from 22,000 to 39,000 acre-ft per year. Declining water levels are an indication of the estimated average annual decrease in groundwater storage of 15,000 acre-ft from 1994 to 2013.Groundwater and surface-water samples were collected from 46 sites in Parowan Valley and Cedar Valley near the town of Enoch during June 2013. Groundwater samples from 34 wells were submitted for geochemical analysis. The total dissolved-solids concentration in water from these wells ranged from 142 to 886 milligrams per liter. Results of stable isotope analysis of oxygen and deuterium from groundwater and surface-water samples indicate that most of the groundwater in Parowan Valley and in Cedar Valley near Enoch is similar in isotopic composition to water from mountain streams, which reflects meteoric water recharged in high-altitude areas east of the valley. In addition, results of stable isotope analysis of a subset of samples from wells located near Little Salt Lake may indicate recharge of precipitation that occurred during cooler climatic conditions of the Pleistocene Epoch.
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 commonly associated with deposition of glacial outwash or bouldery glacial-flood deposits. Many previously unrecognized Neogene and Quaternary faults, some of the latter with possible Holocene displacement, have been identified on lidar (light detection and ranging) imagery which covers 59 percent of the map area. This imagery has also permitted more accurate remapping of glacial, fluvial, and mass-movement deposits and aided in the determination of their relative ages. Recently published 10beryllium cosmogenic surface-exposure ages, coupled with our new geologic mapping, have revealed the timing and rates of late Pleistocene deglaciation. Glacial dams that impounded the Arkansas River at Clear Creek and possibly at Pine Creek failed at least three times during the middle and late Pleistocene, resulting in catastrophic floods and deposition of enormous boulders and bouldery alluvium downstream; at least two failures occurred during the late Pleistocene during the Pinedale glaciation.
Mentaberre, Gregorio; Gutiérrez, Carlos; Rodríguez, Noé F; Joseph, Sunitha; González-Barrio, David; Cabezón, Oscar; de la Fuente, José; Gortazar, Christian; Boadella, Mariana
2013-12-27
The Canary Islands contain the most important dromedary camel (Camelus dromedarius) population in the European Union and are the main export point of dromedaries to continental Europe and Latin America. We investigated the presence of antibodies against relevant disease agents in 100 Canarian camel sera. Selected blood samples of the same animals were also tested by PCR. Sera were tested for antibodies against Bluetongue virus (BTV; 0%), Bovine Viral Diarrhoea virus (BVDV; 0%), Camelpox virus (CPV; 8% by serum neutralization, 16% by ELISA), Peste des Petits Ruminants virus (PPRV, 0%), Rift Valley Fever virus (RVFV; 0%) and West Nile Fever virus (WNV; 3%), the bacterial pathogens Anaplasma sp. (3%), Brucella sp. (1%), Coxiella burnetii (19%), Mycobacterium avium paratuberculosis (MAP; 22%), Mycobacterium tuberculosis complex (MTC; 10%) and Rickettsia sp. (83%), and the parasites Toxoplasma gondii (36%) and Neospora caninum (86%). The most remarkable findings were the detection of antibodies against CPV and the high antibody prevalence against C. burnetii, Rickettsia sp., T. gondii and N. caninum. By PCR, we found no C. burnetii, N. caninum and Anaplasma sp. DNA in the tested samples. However, Rickettsia sp. DNA was detected in six antibody positive tested samples. These results should be taken into consideration in order to implement adequate control measures and avoid a potential dissemination of infections to other territories. Copyright © 2013 Elsevier B.V. All rights reserved.
Valley splitting of single-electron Si MOS quantum dots
Gamble, John King; Harvey-Collard, Patrick; Jacobson, N. Tobias; ...
2016-12-19
Here, silicon-based metal-oxide-semiconductor quantum dots are prominent candidates for high-fidelity, manufacturable qubits. Due to silicon's band structure, additional low-energy states persist in these devices, presenting both challenges and opportunities. Although the physics governing these valley states has been the subject of intense study, quantitative agreement between experiment and theory remains elusive. Here, we present data from an experiment probing the valley states of quantum dot devices and develop a theory that is in quantitative agreement with both this and a recently reported experiment. Through sampling millions of realistic cases of interface roughness, our method provides evidence that the valley physicsmore » between the two samples is essentially the same.« less
NASA Technical Reports Server (NTRS)
Ashwal, Lewis D.; Wooden, Joseph L.
1989-01-01
This paper presents Nd, Sr, and Pb isotopic data indicating a late-Archean/early-Proterozoic age for the River Valley anorthositic pluton of the southwestern Grenville Province of Sudbury, Ontario. Pb-Pb isotopic data on 10 whole-rock samples ranging in composition from anorthosite to gabbro yield an age of 2560 + or - 155 Ma. The River Valley pluton is thus the oldest anorthositic intrusive yet recognized within the Grenville Province. The Sm-Nd isotopic system records an age of 2377 + or - 68 Ma. High Pb-208/Pb-204 of deformed samples relative to igneous-textured rocks implies Th introduction and/or U loss during metamorphism in the River Valley area. Rb-Sr data from igneous-textured and deformed samples and from mineral separates give an age of 2185 + or - 105 Ma, indicating substantial disturbance of the Rb-Sr isotopic system.
Geologic map of the Harvard Lakes 7.5' quadrangle, Park and Chaffee Counties, Colorado
Kellogg, Karl S.; Lee, Keenan; Premo, Wayne R.; Cosca, Michael A.
2013-01-01
The Harvard Lakes 1:24,000-scale quadrangle spans the Arkansas River Valley in central Colorado, and includes the foothills of the Sawatch Range on the west and Mosquito Range on the east. The Arkansas River valley lies in the northern end of the Rio Grande rift and is structurally controlled by Oligocene and younger normal faults mostly along the west side of the valley. Five separate pediment surfaces were mapped, and distinctions were made between terraces formed by the Arkansas River and surfaces that formed from erosion and alluviation that emanated from the Sawatch Range. Three flood deposits containing boulders as long as 15 m were deposited from glacial breakouts just north of the quadrangle. Miocene and Pliocene basin-fill deposits of the Dry Union Formation are exposed beneath terrace or pediment deposits in several places. The southwestern part of the late Eocene Buffalo Peaks volcanic center, mostly andesitic breccias and flows and ash-flow tuffs, occupy the northeastern corner of the map. Dated Tertiary intrusive rocks include Late Cretaceous or early Paleocene hornblende gabbro and hornblende monzonite. Numerous rhyolite and dacite dikes of inferred early Tertiary or Late Cretaceous age also intrude the basement rocks. Basement rocks are predominantly Mesoproterozoic granites, and subordinately Paleoproterozoic biotite gneiss and granitic gneiss.
In summer 1997, we sampled reaches in 24 wadeable, Willamette Valley ecoregion streams draining agriculturally-infiuenced watersheds. Within these reaches, physical habitat, water chemistry, aquatic invertebrate and fish data and samples were collected. Low-level air photos were ...
2012-01-01
Background Although the experiences of unintended pregnancies and poor birth outcomes among adolescents aged 15–19 years in the general population are well documented, there is limited understanding of the same among those who are living with HIV. This paper examines the factors associated with experiencing unintended pregnancies, poor birth outcomes, and post-partum contraceptive use among HIV-positive female adolescents in Kenya. Methods Data are from a cross-sectional study that captured information on pregnancy histories of HIV-positive female adolescents in four regions of Kenya: Coast, Nairobi, Nyanza and Rift Valley provinces. Study participants were identified through HIV and AIDS programs in the four regions. Out of a total of 797 female participants, 394 had ever been pregnant with 24% of them experiencing multiple pregnancies. Analysis entails the estimation of random-effects logit models. Results Higher order pregnancies were just as likely to be unintended as lower order ones (odds ratios [OR]: 1.2; 95% confidence interval [CI]: 0.8–2.0) while pregnancies occurring within marital unions were significantly less likely to be unintended compared to those occurring outside such unions (OR: 0.1; 95% CI: 0.1–0.2). Higher order pregnancies were significantly more likely to result in poor outcomes compared to lower order ones (OR: 2.5; 95% CI: 1.6–4.0). In addition, pregnancies occurring within marital unions were significantly less likely to result in poor outcomes compared to those occurring outside such unions (OR: 0.3; 95% CI: 0.1–0.9). However, experiencing unintended pregnancy was not significantly associated with adverse birth outcomes (OR: 1.3; 95% CI: 0.5–3.3). There was also no significant difference in the likelihood of post-partum contraceptive use by whether the pregnancy was unintended (OR: 0.9; 95% CI: 0.5–1.5). Conclusions The experience of repeat unintended pregnancies among HIV-positive female adolescents in the sample is partly due to inconsistent use of contraception to prevent recurrence while poor birth outcomes among higher order pregnancies are partly due to abortion. This underscores the need for HIV and AIDS programs to provide appropriate sexual and reproductive health information and services to HIV-positive adolescent clients in order to reduce the risk of undesired reproductive health outcomes. PMID:23039966
King, N.E.; Argus, D.; Langbein, J.; Agnew, D.C.; Bawden, G.; Dollar, R.S.; Liu, Z.; Galloway, D.; Reichard, E.; Yong, A.; Webb, F.H.; Bock, Y.; Stark, K.; Barseghian, D.
2007-01-01
Starting early in 2005, the positions of GPS stations in the San Gabriel valley region of southern California showed statistically significant departures from their previous behavior. Station LONG moved up by about 47 mm, and nearby stations moved away from LONG by about 10 mm. These changes began during an extremely rainy season in southern California and coincided with a 16-m increase in water level at a nearby well in Baldwin Park and a regional uplift detected by interferometric synthetic aperture radar. No equivalent signals were seen in GPS station position time series elsewhere in southern California. Our preferred explanation, supported by the timing and by a hydrologic simulation, is deformation due to recharging of aquifers after near-record rainfall in 2004-2005. We cannot rule out an aseismic slip event, but we consider such an event unlikely because it requires slip on multiple faults and predicts other signals that are not observed. Copyright 2007 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Yang, M. M.; Meinardi, S.; Krauter, C.; Blake, D.
2008-12-01
The San Joaquin Valley Air Basin in Central California is classified by the U.S. Environmental Protection Agency (EPA) as a serious non-attainment area for health-based eight-hour federal ozone (smog) standard (1). In August 2005, the San Joaquin Valley Air Pollution Control District issued a report identifying dairies as a main source of Volatile Organic Compounds (VOCs) and fine particulate matter in the valley (2). Among these compounds, we have found that ethanol, methanol, acetone and acetaldehyde are produced in major quantities throughout the San Joaquin valley as by-products of yeast fermentation of silage and photochemical oxidation. These oxygenates, especially ethanol, play an important role in ozone (O3) formation within the valley. Three different types of sampling protocols were employed in order to determine the degree of enhancement of the four oxygenates in the valley air shed, as well as to determine their sources, emission profiles and emission rates. An assessment of the emissions of these oxygenates in the valley was achieved using data obtained on low altitude flights through the valley and from ground level samples collected thoughout the valley. The photochemical production of ozone was calculated for each of the four oxygenates and approximately one hundred other quantified VOCs. Based on the Maximum Incremental Reactivity (MIR) scale and concentrations of each oxygenate in the atmosphere, as much as 20% of O3 production in the valley is from ethanol and its photochemical by-product acetaldehyde. Our findings suggest that improvement to the valley air quality may be obtained by focusing on instituting new silage containment practices and regulations. 1. Lindberg, J. "Analysis of the San Joaquin Valley 2007 Ozone Plan." State of California Air Resources Board. Final Draft Staff Report. 5/30/2007. 2. Crow, D., executive director/APCO. "Air Pollution Control Officer's Determination of VOC Emisison Factors for Dairies." San Joaquin Valley Air Pollution Control District. Aug. 1st 2005.
Lowe, Mike; Miner, Michael L.; ,
1990-01-01
Ground water in Ogden Valley occurs in perched, confined, and unconfined aquifers in the valley fill to depths of 600 feet and more. The confined aquifer, which underlies only the western portion of the valley, is overlain by cleyey silt lacustrine sediments probably deposited during the Bonneville Basin's Little Valley lake cycle sometime between 90,000 and 150,000 years ago. The top of this cleyey silt confining layer is generally 25 to 60 feet below the ground surface. Unconfined conditions occur above and beyond the outer margin of the confining layer. The sediments overlying the confining layer are primarily Lake Bonneville deposits. Water samples from springs, streams, and wells around Pineview Reservoir, and from the reservoir itself, were collected and analyzed. These samples indicate that water quality in Ogden Valley is presently good. Average nitrate concentrations in the shallow unconfined aquifer increase toward the center of Ogden Valley. This trend was not observed in the confined aquifer. There is no evidence, however, of significant water-quality deterioration, even in the vicinity of Huntsville, a town that has been densely developed using septic-tank-soil-absorption systems for much of the time since it was founded in 1860.
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.
Dettinger, M.D.
1987-01-01
As a result of rapid urban growth in Las Vegas Valley, rates of water use and wastewater disposal have grown rapidly during the last 25 years. Concern has developed over the potential water quality effects of this growth. The deep percolation of wastewater and irrigation return flow (much of which originates as imported water from Lake Mead), along with severe overdraft conditions in the principal aquifers of the valley, could combine to pose a long-term threat to groundwater quality. The quantitative investigations of groundwater quality and geochemical conditions in the valley necessary to address these concerns would include the establishment of data collection networks on a valley-wide scale that differ substantially from existing networks. The valley-wide networks would have a uniform areal distribution of sampling sites, would sample from all major depth zones, and would entail repeated sampling from each site. With these criteria in mind, 40 wells were chosen for inclusion in a demonstration monitoring network. Groundwater in the northern half of the valley generally contains 200 to 400 mg/L of dissolved solids, and is dominated by calcium, magnesium , and bicarbonate ions, reflecting a chemical equilibrium between the groundwater and the dominantly carbonate rocks in the aquifers of this area. The intermediate to deep groundwater in the southern half of the valley is of poorer quality (containing 700 to 1,500 mg/L of dissolved solids) and is dominated by calcium, magnesium, sulfate, and bicarbonate ions, reflecting the occurrence of other rock types including evaporite minerals among the still-dominant carbonate rocks in the aquifers of this part of the valley. The poorest quality groundwater in the valley is generally in the lowland parts of the valley in the first few feet beneath the water table, where dissolved solids concentrations range from 2,000 to > 7,000 mg/L , and probably reflects the effects of evaporite dissolution, secondary recharge, and evapotranspiration. The most common water quality constraint on potential groundwater use is the high salinity. No evidence of large-scale contamination of deep groundwater was found in this study. (Author 's abstract)
An assessment of nonpoint-source discharges, streamflow, and water quality in Onion River, Wisconsin
Field, S.J.; Lidwin, R.A.
1984-01-01
All samples at both Hingham and Sheboygan Falls contained concentrations of un-ionized ammonia that were less than the U.S. Environmental Protection Agency's criteria (0.02 milligrams per liter), except the March 1980 samples. No samples exceeded the Wisconsin Department of Natural Resources criteria for un-ionized ammonia (0.04 milligrams per liter).
Densmore, Jill N.; Belitz, Kenneth; Wright, Michael T.; Dawson, Barbara J.; Johnson, Tyler D.
2005-01-01
The California Aquifer Susceptibility Assessment of the Ground-Water Ambient Monitoring and Assessment Program was developed to assess water quality and susceptibility of ground-water resources to contamination from surficial sources. This study focuses on the Mojave River and the Antelope Valley ground-water basins in southern California. Volatile organic compound (VOC) data were evaluated in conjunction with tritium data to determine a potential correlation with aquifer type, depth to top of perforations, and land use to VOC distribution and occurrence in the Mojave River and the Antelope Valley Basins. Detection frequencies for VOCs were compiled and compared to assess the distribution in each area. Explanatory variables were evaluated by comparing detection frequencies for VOCs and tritium and the number of compounds detected. Thirty-three wells were sampled in the Mojave River Basin (9 in the floodplain aquifer, 15 in the regional aquifer, and 9 in the sewered subset of the regional aquifer). Thirty-two wells were sampled in the Antelope Valley Basin. Quality-control samples also were collected to identify, quantify, and document bias and variability in the data. Results show that VOCs generally were detected slightly more often in the Antelope Valley Basin samples than in the Mojave River Basin samples. VOCs were detected more frequently in the floodplain aquifer than in the regional aquifer and the sewered subset. Tritium was detected more frequently in the Mojave River Basin samples than in the Antelope Valley Basin samples, and it was detected more frequently in the floodplain aquifer than in the regional aquifer and the sewered subset. Most of the samples collected in both basins for this study contained old water (water recharged prior to 1952). In general, in these desert basins, tritium need not be present for VOCs to be present. When VOCs were detected, young water (water recharge after 1952) was slightly more likely to be contaminated than old water. Trihalomethanes (THMs) were detected less frequently in the Mojave River Basin samples than in the Antelope Valley Basin samples. The THMs that were detected in the Mojave River Basin were detected more frequently in the floodplain aquifer than in the regional aquifer and sewered subset. Solvents were detected more frequently in the Mojave River samples than in the Antelope Valley samples. In the Mojave River Basin samples, solvents were detected less frequently in the floodplain aquifer than in the regional aquifer and the sewered subset. Benzene, toluene, ethylbenzene and xylene (BTEX) were not detected in either study area. Methyl tert-butyl ether (MTBE) was detected in one sample from both the Mojave River and Antelope Valley Basins. The most frequently detected compound (detected in more than 10 percent of the wells) in the Mojave River Basin was chloroform. The two most frequently detected compounds in the Antelope Valley Basin were chloroform and tetrachloroethylene (PCE). In the Mojave River Basin, aquifer type and land use within 1,640 ft (500 m) of the well head were not statistically correlated with the number of VOCs detected, although VOCs were detected more frequently in the floodplain aquifer than in the regional aquifer and the sewered subset. Depth to the top of the perforations was an explanatory factor for the number of VOCs detected in the Mojave River Basin; the detection frequency was greater for shallow wells than for deep wells. In the Antelope Valley Basin, neither aquifer type, depth to the top of the perforations, nor land use within 1,640 ft of the well head were explanatory factors for the number of VOCs detected. Although aquifer type and depth to top of the perforations did explain the presence of tritium in the Mojave River Basin, land use within 1,640 ft of the well head was not a statistically significant explanatory factor for the presence of tritium in this basin. Aquifer type, depth to the top of the perfora
Ground-water-quality and ground-water-level data, Bernalillo County, central New Mexico, 1990-1993
Kues, G.E.; Garcia, B.M.
1995-01-01
Ground-water-quality and ground-water-level data were collected in four unincorporated areas of Bernalillo County during 1990-93. Twenty wells in the east mountain area of Bernalillo County were sampled approximately monthly between January 1990 and June 1993. The water samples were analyzed for concentrations of chloride and selected nutrient species; many of the samples also were analyzed for concentrations of total organic carbon and dissolved boron and iron. Eleven wells northeast of the city of Albuquerque, 20 wells in the Rio Grande Valley immediately north of Albuquerque, and 30 wells in the Rio Grande Valley immediately south of Albuquerque were sampled once each between December 1992 and September 1993; all water samples were analyzed for chloride and selected nutrient species, and selected samples from wells in the north and south valley areas were also analyzed for major dissolved constituents, iron, manganese, and methylene blue active substances. Samples from 10 of the wells in the north and south valley areas were analyzed for 47 selected pesticides. Field measurements of specific conductance, pH, temperature, and alkalinity were made on most samples at the time of sample collection. Water levels also were measured at the time of sample collection when possible. Results of the monthly water-quality and water-level monitoring in the east mountain area of Bernalillo County are presented in graphical form. Water-quality and water-level data collected from the other areas are presented in tabular form.
Geology and ground-water resources of upper Grande Ronde River Basin, Union County, Oregon
Hampton, E.R.; Brown, S.G.
1964-01-01
The upper Grande Ronde River basin is a 1,400-square-mile area in northeastern Oregon, between the Blue Mountains to the west and the Wallowa Mountains to the east. The area is drained by the Grande Ronde River, which flows northeast through this region and is tributary to the Snake River. The climate is generally moderate; temperature extremes recorded at La Grande are 22?F. below zero and 108?F. above. The average annual precipitation ranges from 13 to 20 inches in the Grande Ronde Valley to . more than 35 inches in the mountain highlands surrounding the valley. The topography of. the area is strongly controlled by the geologic structures, principally those related to block faulting. The terrain ranges from the nearly flat floors of the Grande Ronde and Indian Valleys, whose elevations are 2,600 to about 2,750 feet, to the mountainous uplands, whose average elevations are about 5,000 feet and which have local prominences exceeding 6,500 feet. The rocks in the upper Grande Ronde River basin, from oldest to youngest, are metamorphic rocks of pre-Tertiary age; igneous masses of diorite and granodiorite that intruded the metamorphic rocks; tuff-breccia, welded and silicified tuff, and andesite and dacite flows, of Tertiary age; the Columbia River basalt of Miocene and possibly early Pliocene age; fanglomerate and lacustrine deposits of Pliocene and Pleistocene age; and younger deposits . of alluvium, colluvium, and welded tuff. In the graben known as the Grande Ronde Valley, which is the principal populated district in the area, the valley fill deposits are as thick as 2,000 feet. The valley is bordered by the scarps of faults, the largest of which have displacements of more than 4.000 feet. Most of the wells in the area obtain small to moderate supplies of water from unconfined aquifers in the val1ey fill and alluvial fan deposits. Moderate to large quantities of water are obtained from aquifers carrying artesian water in the fan alluvium and the Columbia River basalt. The available supplies of ground water greatly exceed the relatively small amounts that are being used, and the natural supplies are ..adequate for foreseeable domestic, industrial, irrigation, and municipal. requirements. Yields of future wells probably could be improved appreciably over those of present wells by exercising close attention to subsurface conditions during construction, and by greater use of well screens, gravel envelopes, and well development techniques. The chemical quality of the ground water in general is excellent. All waters sampled are potable and are within the desired ranges of hardness and salinity for most public, industrial, and irrigation uses. The average temperature of shallow ground water drawn from, the alluvial fill was 3?F. above the mean annual air temperature. That of water obtained from the basalt is 6?F. above the temperatures computed from the 'normal' gradient of 1.8?F. per 100 feet of increased depth.
Superior Valley Polarization and Coherence of 2s Excitons in Monolayer WSe_{2}.
Chen, Shao-Yu; Goldstein, Thomas; Tong, Jiayue; Taniguchi, Takashi; Watanabe, Kenji; Yan, Jun
2018-01-26
We report the experimental observation of 2s exciton radiative emission from monolayer tungsten diselenide, enabled by hexagonal boron nitride protected high-quality samples. The 2s luminescence is highly robust and persists up to 150 K, offering a new quantum entity for manipulating the valley degree of freedom. Remarkably, the 2s exciton displays superior valley polarization and coherence than 1s under similar experimental conditions. This observation provides evidence that the Coulomb-exchange-interaction-driven valley-depolarization process, the Maialle-Silva-Sham mechanism, plays an important role in valley excitons of monolayer transition metal dichalcogenides.
Superior Valley Polarization and Coherence of 2 s Excitons in Monolayer WSe2
NASA Astrophysics Data System (ADS)
Chen, Shao-Yu; Goldstein, Thomas; Tong, Jiayue; Taniguchi, Takashi; Watanabe, Kenji; Yan, Jun
2018-01-01
We report the experimental observation of 2 s exciton radiative emission from monolayer tungsten diselenide, enabled by hexagonal boron nitride protected high-quality samples. The 2 s luminescence is highly robust and persists up to 150 K, offering a new quantum entity for manipulating the valley degree of freedom. Remarkably, the 2 s exciton displays superior valley polarization and coherence than 1 s under similar experimental conditions. This observation provides evidence that the Coulomb-exchange-interaction-driven valley-depolarization process, the Maialle-Silva-Sham mechanism, plays an important role in valley excitons of monolayer transition metal dichalcogenides.
Prospects for developing stock - Water supplies from wells in northeastern Garfield County, Montana
Van Lewen, M. C.; King, Norman Julius
1971-01-01
Ground-water resources in northeastern Garfield County, Mont., afford a practical and reliable source of stock water on the intermingled public and private grazing lands that together comprise an area of about 1,200 square miles. The oldest formation exposed in the area is the relatively thick and impermeable Bearpaw Shale of Cretaceous .age. Overlying the Bearpaw Shale in succession are the Fox Hills Sandstone and Hell Creek Formation of Cretaceous age, the Fort Union Formation of Tertiary age, and thin glacial deposits .and alluvium of Quaternary age. All but the Bearpaw Shale and the glacial deposits are potential aquifers. Published geologic maps were found to be satisfactory after fitting contacts to the topographic base. Mapping, therefore, was limited mainly to outlining on aerial photographs the alluvial deposits in the stream valleys. The major structural feature is the Blood Creek syncline, the axis of which plunges eastward 10-15 feet per mile across the southern part of the area. Beds generally dip 15-25 feet per mile toward the synclinal axis. Water in bedrock aquifers is under artesian pressure, .and most wells in Big and Little Dry Creek valleys flow at the land surface. The only bedrock aquifer having appreciable areal extent is a sandstone 30-70 feet thick that has been mapped by previous investigators as the upper part of the Fox Hills Sandstone. This aquifer crops out in the northern and northwestern parts of the area and dips about 20 feet per mile southeastward beneath younger beds. Most wells in the northern half of the area obtain water from this sandstone at drilling depths of less than 200 feet. The depth to the Fox Hills Sandstone increases progressively southward, and most wells south of Woody Creek obtain water from irregularly distributed sandstone beds and lenses in the overlying Hell Creek and Fort Union Formations. The depth at which water may be obtained from these beds is not accurately predictable, but the depth seldom exceeds 300 feet. The results of the investigation indicate that the prospects for obtaining ample water for livestock from wells drilled into the bedrock formations are very favorable in most of the area. The average depth of bedrock wells in the area is 195 feet. Underflow in the alluvial deposits along all the larger stream valleys also affords a practical source of stock water. Chemical analyses of samples collected at 43 wells and three springs show the water quality to be generally poor. Water from bedrock aquifer contains 530-5,340 milligrams per liter total dissolved solids, whereas water from alluvium contains less than 1,500 milligrams per liter total dissolved solids. The predominant constituents are sodium, bicarbonate, and sulfate. So far as could be determined, all water supplies in the area are suitable for livestock.
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.
Ana L. Albarrán-Lara; Jessica W. Wright; Paul F. Gugger; Annette Delfino-Mix; Juan Manuel Peñaloza-Ramírez; Victoria L. Sork
2015-01-01
California oaks exhibit tremendous phenotypic variation throughout their range. This variation reflects phenotypic plasticity in tree response to local environmental conditions as well as genetic differences underlying those phenotypes. In this study, we analyze phenotypic variation in leaf traits for valley oak adults sampled along three elevational transects and in...
Thomas, Mary Ann
2003-01-01
Ground-water-quality data collected as part of 12 U.S. Geological Survey National Water-Quality Assessment studies during 1996-2001 were analyzed to (1) document arsenic occurrence in four types of gla-cial deposits that occur in large areas of the Midwest, (2) identify hydrogeologic or geochemical factors asso-ciated with elevated arsenic concentrations, and (3) search for clues as to arsenic source(s) or mechanism(s) of mobilization that could be useful for designing future studies. Arsenic and other water-quality constituents were sampled in 342 monitor and domestic wells in parts of Illinois Indiana Ohio Michigan and Wisconsin. Arsenic was detected (at a concentration >1 ?g/L) in one-third of the samples. The maximum concentration was 84 ?g/L, and the median was less than 1 ?g/L. Eight percent of samples had arsenic concentrations that exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level (MCL) of 10?g/L. Samples were from four aquifer types?confined valley fill, unconfined valley fill, outwash plain, and till with sand lenses. Highest arsenic concentrations were found in reducing waters from valley-fill depos-its. In confined valley fill, all waters were reducing and old (recharged before 1953), and almost half of sam-ples had arsenic concentrations greater than the MCL. In unconfined valley fill, redox conditions and ages were varied, and elevated arsenic concentrations were sporadic. In both types of valley fill, elevated arsenic concentrations are linked to the underlying bedrock on the basis of spatial relations and geochemical correla-tions. In shallow (150 ft), all deep wells were from a distinctive aquifer type (confined valley fill). It is not known whether wells at similar depths in other aquifer types would produce waters with simi-larly high arsenic concentrations. Correlations of arsenic with fluoride, strontium, and barium suggest that arsenic might be related to epi-genetic (Mississippi Valley-type) sulfide deposits in Paleozoic bedrock. Arsenic is typically released from sulfides by oxidation, but in the current study, the highest arsenic concentrations in glacial deposits were detected in reducing waters. Therefore, a link between epigenetic sulfides and elevated arsenic concentrations in glacial deposits would probably require a multi-step process.
PIXE Analysis of Indoor Aerosols
NASA Astrophysics Data System (ADS)
Johnson, Christopher; Turley, Colin; Moore, Robert; Battaglia, Maria; Labrake, Scott; Vineyard, Michael
2011-10-01
We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol samples collected in academic buildings at Union College to investigate the air quality in these buildings and the effectiveness of their air filtration systems. This is also the commissioning experiment for a new scattering chamber in the Union College Ion-Beam Analysis Laboratory. The aerosol samples were collected on Kapton foils using a nine-stage cascade impactor that separates particles according to their aerodynamic size. The foils were bombarded with beams of 2.2-MeV protons from the Union College 1.1-MV Pelletron Accelerator and the X-ray products were detected with an Amptek silicon drift detector. After subtracting the contribution from the Kapton foils, the X-ray energy spectra of the aerosol samples were analyzed using GUPIX software to determine the elemental concentrations of the samples. We will describe the collection of the aerosol samples, discuss the PIXE analysis, and present the results.
Assessment of surface water quality of inland valleys for cropping in SW Nigeria
NASA Astrophysics Data System (ADS)
Aboyeji, O. S.; Ogunkoya, O. O.
2017-05-01
Inland valley agro-ecosystems which are a category of wetlands have potential for sustainable crop production relative to uplands. A major challenge to their utilisation in the study area is their heterogeneity in hydrology, morphology, soil types and agro-economy. The study assessed the surface water quality of three typologies of the agro-ecosystems—amphitheatre-like valley-heads (Am), valley-side (VS), and low depression (LD)—for cropping. Surface water of six sites were sampled during the wet and dry seasons. The physicochemical properties and metal concentrations of the samples were analysed. Descriptive statistics and water quality indices were used to assess the suitability of the waters of the agro-ecosystems for cropping. Results showed that the valleys have neutral to slightly alkaline waters. Values of physicochemical parameters are generally within the acceptable range for cropping. The concentration of major cations varied across the inland valley types, but exhibited similar characteristics within each valley. The dominance of the major cations is in the order of Na > Ca > K > Mg. ANOVA results indicated that there is no significant difference in the concentration of heavy metals across the valleys ( F = 2.044, p = 0.138, α = 0.05). Generally, most of the physicochemical parameters and trace metals have low concentrations and are non-toxic to plants. Values of water quality indices (sodium adsorption ratio, soluble sodium percentage, total dissolved solids and permeability index) indicated that the concentrations of minerals in waters across the valley typologies are generally within permissible limits for cropping.
Unstable ground in western North Dakota
Trimble, Donald E.
1979-01-01
Unstable ground in western North Dakota is mainly the result of mass-wasting processes. The units most affected are mudstones, siltstones, and sandstones of the Fort Union Formation. Ground instability generally is indicated by landslides, soil slides, or subsidence. Landslides are mostly of the slump-earthflow type and are localized along the flanks of the high buttes in southwestern North Dakota, including HT (Black) Butte, Chalky Buttes, Sentinel Butte, and East and West Rainy Buttes, and along parts of the valleys of the Des Lacs, Missouri, Little Missouri, and Heart Rivers. Landslides are sparse elsewhere. Soil slides are common in the areas south and southwest of the maximum position of the Pleistocene glacial ice margin on slopes of 15 degrees or more, and have taken place on some slopes as gentle as five degrees. The weathered, exposed surface of the Fort Union Formation seems to be especially susceptible to soil slides. Soil slides constitute the major type of ground instability in southwestern North Dakota. Subsidence is of two types: (1) subsidence over old underground mine workings, and (2) subsidence over naturally ignited and burned underground coal beds. Major subsidence has taken place over old, underground workings near Beulah, Wilton, Lehigh, Haynes, and Belfield, and lesser subsidence near Scranton, and west and north of Bowman. Thickness of overburden above the coal in all these areas is believed to be less than 30 m (100 ft). Subsidence has not taken place over old underground workings along the Des Lacs and-Souris valleys northwest of Minot, where the thickness of overburden is more than 60 m (200 ft). Spectacular subsidence has occurred over a burning underground coal bed at Burning Coal Vein Park near the Little Missouri River, northwest of Amidon.
Soil developments in polar deserts: Implications for exobiology and future Mars missions
NASA Technical Reports Server (NTRS)
Gibson, Everett K., Jr.
1989-01-01
Chemical alterations, weathering, and diagenesis of soil profiles from the dry valleys of Antarctica were studied as analogs of regolith development for the Martian regolith. Chemical weathering processes play an important part in soil development within the dry valleys of Antarctica. A suite of core samples were studied which were taken within the valley floors in addition to samples taken in the vicinity of evaporite and brine ponds. Analysis of water soluable cations and anions from core samples were performed along with petrographic analysis of selected samples. It was shown that ionic transport processes operate primarily above the permafrost zone. Abundances of the water soluable ions reflect the nature of secondary minerals produced by evaporation and weathering. Chloride, calcium, and sodium abundances for soils from the cores within the North and South Forks of Wright Valley, reflect the secondary mineralogy of the soil columns. Calculations for Na, Ca, and Cl abundances reflect the appearance of halite and antarcticite. In areas where excess Ca is present, X-ray diffraction studies show the presence of gypsum. It is well known that the Martian surface conditions may be favorable for chemical weathering. Primary silicates would be expected to be reactive with any ground water. It seems likely that Martian subsurface water is available to assist in the weathering of the primary minerals. Such weathering could result in the formation of clays, sulfates, carbonates, hydrates, halides, and zeolites. The dry valley cores have shown that they maybe excellent analogs to weathering processes on the near-surface of Mars. Since movement of water within the near-surface region clearly results in chemical weathering, leaching, and salt formation in the dry valleys, similar processes are probably operating within the Martian regolith.
Parliman, D.J.; Boyle, Linda; Nicholls, Sabrina
1996-01-01
Water samples were collected from 903 wells in the Boise River Valley, Idaho, from January 1990 through December 1995. Selected well information and analyses of 1,357 water samples are presented. Analyses include physical properties ad concentrations of nutrients, bacteria, major ions, selected trace elements, radon-222, volatile organic compounds, and pesticides.
Publications - GMC 278 | Alaska Division of Geological & Geophysical
DGGS GMC 278 Publication Details Title: High pressure methane adsorption analyses for coal samples of the Matanuska Valley coal-bed methane AK 94-CBM-1 hole as follows: Seam #1, Seam #6, Seam #9, and Seam , High pressure methane adsorption analyses for coal samples of the Matanuska Valley coal-bed methane AK
Gardner, Philip M.; Kirby, Stefan
2011-01-01
The water resources of Rush Valley were assessed during 2008–2010 with an emphasis on refining the understanding of the groundwater-flow system and updating the groundwater budget. Surface-water resources within Rush Valley are limited and are generally used for agriculture. Groundwater is the principal water source for most other uses including supplementing irrigation. Most groundwater withdrawal in Rush Valley is from the unconsolidated basin-fill aquifer where conditions are generally unconfined near the mountain front and confined at lower altitudes near the valley center. Productive aquifers also occur in fractured bedrock along the valley margins and beneath the basin-fill deposits in some areas.Drillers’ logs and geophysical gravity data were compiled and used to delineate seven hydrogeologic units important to basin-wide groundwater movement. The principal basin-fill aquifer includes the unconsolidated Quaternary-age alluvial and lacustrine deposits of (1) the upper basin-fill aquifer unit (UBFAU) and the consolidated and semiconsolidated Tertiary-age lacustrine and alluvial deposits of (2) the lower basin-fill aquifer unit (LBFAU). Bedrock hydrogeologic units include (3) the Tertiary-age volcanic unit (VU), (4) the Pennsylvanian- to Permian-age upper carbonate aquifer unit (UCAU), (5) the upper Mississippian- to lower Pennsylvanian-age upper siliciclastic confining unit (USCU), (6) the Middle Cambrian- to Mississippian-age lower carbonate aquifer unit (LCAU), and (7) the Precambrian- to Lower Cambrian-age noncarbonate confining unit (NCCU). Most productive bedrock wells in the Rush Valley groundwater basin are in the UCAU.Average annual recharge to the Rush Valley groundwater basin is estimated to be about 39,000 acre-feet. Nearly all recharge occurs as direct infiltration of snowmelt and rainfall within the mountains with smaller amounts occurring as infiltration of streamflow and unconsumed irrigation water at or near the mountain front. Groundwater generally flows from the higher altitude recharge areas toward two distinct valley-bottom discharge areas: one in the vicinity of Rush Lake in northern Rush Valley and the other located west and north of Vernon. Average annual discharge from the Rush Valley groundwater basin is estimated to be about 43,000 acre-feet. Most discharge occurs as evapotranspiration in the valley lowlands, as discharge to springs and streams, and as withdrawal from wells. Subsurface discharge outflow to Tooele and Cedar Valleys makes up only a small fraction of natural discharge.Groundwater samples were collected from 25 sites (24 wells and one spring) for geochemical analysis. Dissolved-solids concentrations in water from these sites ranged from 181 to 1,590 milligrams per liter. Samples from seven wells contained arsenic concentrations that exceed the Environmental Protection Agency Maximum Contaminant Level of 10 micrograms per liter. The highest arsenic levels are found north of Vernon and in southeastern Rush Valley. Stable-isotope ratios of oxygen and deuterium, along with dissolved-gas recharge temperatures, indicate that nearly all modern groundwater is meteoric and derived from the infiltration of high altitude precipitation in the mountains. These data are consistent with recharge estimates made using a Basin Characterization Model of net infiltration that shows nearly all recharge occurring as infiltration of precipitation and snowmelt within the mountains surrounding Rush Valley. Tritium concentrations between 0.4 and 10 tritium units indicate the presence of modern (less than 60 years old) groundwater at 7 of the 25 sample sites. Apparent 3H/3He ages, calculated for six of these sites, range from 3 to 35 years. Adjusted minimum radiocarbon ages of premodern water samples range from about 1,600 to 42,000 years with samples from 11 of 13 sites being more than 11,000 years. These data help to identify areas where modern groundwater is circulating through the hydrologic system on time scales of decades or less and indicate that large parts of the principal basin-fill and the bedrock aquifers are much less active and receive little to no modern recharge.
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 integrated more with the Urals and Western Siberia than with the rest of Kazakhstan. Serious ethnic conflicts in either Kazakhstan or the Ferghana Valley are likely to spill far beyond their local boundaries, embroiling much of the area in hostilities.
Thiros, Susan A.; Manning, Andrew H.
2004-01-01
Ground water supplies about one-third of the water used by the public in Salt Lake Valley, Utah. The occurrence and distribution of natural and anthropogenic compounds in ground water used for public supply in the valley were evaluated. Water samples were collected from 31 public-supply wells in 2001 and analyzed for major ions, trace elements, radon, nutrients, dissolved organic carbon, methylene blue active substances, pesticides, and volatile organic compounds. The samples also were analyzed for the stable isotopes of water (oxygen-18 and deuterium), tritium, chlorofluorocarbons, and dissolved gases to determine recharge sources and ground-water age.Dissolved-solids concentration ranged from 157 to 1,280 milligrams per liter (mg/L) in water from the 31 public-supply wells. Comparison of dissolved-solids concentration of water sampled from the principal aquifer during 1988-92 and 1998-2002 shows a reduction in the area where water with less than 500 mg/L occurs. Nitrate concentration in water sampled from 12 of the 31 public-supply wells was higher than an estimated background level of 2 mg/L, indicating a possible human influence. At least one pesticide or pesticide degradation product was detected at a concentration much lower than drinking-water standards in water from 13 of the 31 wells sampled. Chloroform was the most frequently detected volatile organic compound (17 of 31 samples). Its widespread occurrence in deeper ground water is likely a result of the recharge of chlorinated public-supply water used to irrigate lawns and gardens in residential areas of Salt Lake Valley.Environmental tracers were used to determine the sources of recharge to the principal aquifer used for public supply in the valley. Oxygen-18 values and recharge temperatures computed from dissolved noble gases in the ground water were used to differentiate between mountain and valley recharge. Maximum recharge temperatures in the eastern part of the valley generally are below the range of valley water-table temperatures indicating that mountain-block recharge must constitute a substantial fraction of recharge to the principal aquifer in this area. Together, the recharge temperature and stable-isotope data define two zones with apparently high proportions of valley recharge on the east side of the valley.The possibility of water samples containing a substantial proportion of water recharged before thermonuclear testing began in the early 1950s (pre-bomb) was evaluated by comparing the initial tritium concentration of each sample (measured tritium plus measured tritiogenic helium-3) to that of local precipitation at the apparent time of recharge. Three interpreted-age categories were determined for water from the sampled wells: (1) dominantly pre-bomb; (2) dominantly modern; and (3) modern or a mixture of pre-bomb and modern. Apparent tritium/helium-3 ages range from 3 years to more than 50 years. Water generally becomes older with distance from the mountain front, with the oldest water present in the discharge area.The presence of anthropogenic compounds at concentrations above reporting levels and elevated nitrate concentrations (affected wells) in the principal aquifer is well correlated with the distribution of interpreted-age categories. All of the wells (10 of 10) with dominantly modern water are affected. Seventy percent (7 of 10) of the wells with dominantly modern or a mixture of modern and pre-bomb waters are affected. Only 1 of the 11 wells with dominantly pre-bomb water is affected. Anthropogenic compounds were not detected in water with an apparent age of more than 50 years, except for water from one well. All of the samples that consisted mostly of modern water contained at least one anthropogenic compound.
Hajeb, Parvaneh; Herrmann, Susan S; Poulsen, Mette E
2017-07-19
The guidance document SANTE 11945/2015 recommends that cereal samples be milled to a particle size preferably smaller than 1.0 mm and that extensive heating of the samples should be avoided. The aim of the present study was therefore to investigate the differences in milling procedures, obtained particle size distributions, and the resulting pesticide residue recovery when cereal samples were milled at the European Union National Reference Laboratories (NRLs) with their routine milling procedures. A total of 23 NRLs participated in the study. The oat and rye samples milled by each NRL were sent to the European Union Reference Laboratory on Cereals and Feedingstuff (EURL) for the determination of the particle size distribution and pesticide residue recovery. The results showed that the NRLs used several different brands and types of mills. Large variations in the particle size distributions and pesticide extraction efficiencies were observed even between samples milled by the same type of mill.
Mellor, Steven; Golay, Leslie M
2014-01-01
We tested a theoretically trimmed model of union participation presented by Tetrick, Shore, McClurg, and Vandenberg (2007), in which perceived union instrumentality is expected to influence participation through perceived union support. This testing was accomplished as a precursor to testing a conditional indirect effect model of women's participation--in which perceived union tolerance for sexual harassment was expected to moderate the influence of perceived support on willingness to participate in union activities. In a sample of 326 women from multiple unions, we found support for the conditional model; the influence of perceived instrumentality on willingness to participate through perceived support was moderated by perceived tolerance for harassment; specifically, the influence through perceived support was weak when perceived tolerance was high. The implications of our results are discussed in reference to need support and women's participation.
Diversity of micro-fungi in an Antarctic dry valley
NASA Technical Reports Server (NTRS)
Baublis, J. A.; Wharton, R. A. Jr; Volz, P. A.; Wharton RA, J. r. (Principal Investigator)
1991-01-01
The fungal microflora of a dry valley in Southern Victoria Land near McMurdo Sound, Antarctica, was investigated. Samples were collected from introduced objects such as a mummified penguin and spent chewing tobacco in addition to the sparse soil found in rock fissures, isolated moss colonies, shoreline deposit materials, CaCO3 precipitates, and microbial mat debris obtained from the frozen surface of the lake in the basin of Taylor Valley. Using conventional media and techniques, all collection sites yielded populations of yeasts and filamentous fungi. Water samples and live microbial mats from beneath the lake ice yielded species of fungi along with an abundance of bacteria.
What Whole Rock Samples of Portales Valley Can and Cannot Tell Us
NASA Technical Reports Server (NTRS)
Papanastassiou, D. A.; Chen, J. H.; Wasserburg, G. J.
2002-01-01
We are on our way to deciding that despite significant young disturbances, the Portales Valley breccia maintains vestiges of early formation. Additional information is contained in the original extended abstract.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyrrell, Evan; Denny, Angelita
Fifty-two groundwater samples and one surface water sample were collected at the Monument Valley, Arizona, Processing Site to monitor groundwater contaminants for evaluating the effectiveness of the proposed compliance strategy as specified in the 1999 Final Site Observational Work Plan for the UMTRA Project Site at Monument Valley, Arizona. Sampling and analyses were conducted as specified in the Sampling and Analysis Plan for U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated, http://energy.gov/lm/downloads/sampling-and-analysis-plan-us-department- energy-office-legacy-management-sites). Samples were collected for metals, anions, nitrate + nitrite as N, and ammonia as N analyses at all locations.
Crowley, J.K.; Hook, S.J.
1996-01-01
Efflorescent salt crusts and associated sediments in Death Valley, California, were studied with remote-sensing data acquired by the NASA thermal infrared multispectral scanner (TIMS). Nine spectral classes that represent a variety of surface materials were distinguished, including several classes that reflect important aspects of the playa groundwater chemistry and hydrology. Evaporite crusts containing abundant thenardite (sodium sulfate) were mapped along the northern and eastern margins of the Cottonball Basin, areas where the inflow waters are rich in sodium. Gypsum (calcium sulfate) crusts were more common in the Badwater Basin, particularly near springs associated with calcic groundwaters along the western basin margin. Evaporite-rich crusts generally marked areas where groundwater is periodically near the surface and thus able to replenish the crusts though capillary evaporation. Detrital silicate minerals were prevalent in other parts of the salt pan where shallow groundwater does not affect the surface composition. The surface features in Death Valley change in response to climatic variations on several different timescales. For example, salt crusts on low-lying mudflats form and redissolve during seasonal-to-interannual cycles of wetting and desiccation. In contrast, recent flooding and erosion of rough-salt surfaces in Death Valley probably reflect increased regional precipitation spanning several decades. Remote-sensing observations of playas can provide a means for monitoring changes in evaporite facies and for better understanding the associated climatic processes. At present, such studies are limited by the availability of suitable airborne scanner data. However, with the launch of the Earth Observing System (EOS) AM-1 Platform in 1998, multispectral visible/near-infrared and thermal infrared remote-sensing data will become globally available. Copyright 1996 by the American Geophysical Union.
Influenza-associated mortality in 2009 in four sentinel sites in Bangladesh
Luby, Stephen P; Alamgir, ASM; Islam, Kariul; Paul, Repon; Abedin, Jaynal; Rahman, Mustafizur; Azim, Tasnim; Podder, Goutam; Sohel, Badrul Munir; Brooks, Abdullah; Fry, Alicia M; Widdowson, Marc-Alain; Bresee, Joseph; Rahman, Mahmudur; Azziz-Baumgartner, Eduardo
2012-01-01
Abstract Objective To estimate influenza-associated mortality in Bangladesh in 2009. Methods In four hospitals in Bangladesh, respiratory samples were collected twice a month throughout 2009 from inpatients aged < 5 years with severe pneumonia and from older inpatients with severe acute respiratory infection. The samples were tested for influenza virus ribonucleic acid (RNA) using polymerase chain reaction. The deaths in 2009 in five randomly selected unions (the smallest administrative units in Bangladesh) in each hospital’s catchment area were then investigated using formal records and informal group discussions. The deaths of those who had reportedly died within 14 days of suddenly developing fever with cough and/or a sore throat were assumed to be influenza-associated. The rate of such deaths in 2009 in each of the catchment areas was then estimated from the number of apparently influenza-associated deaths in the sampled unions, the proportion of the sampled inpatients in the local hospital who tested positive for influenza virus RNA, and the estimated number of residents of the sampled unions. Findings Of the 2500 people known to have died in 2009 in all 20 study unions, 346 (14%) reportedly had fever with cough and/or sore throat within 14 days of their deaths. The estimated mean annual influenza-associated mortality in these unions was 11 per 100 000 population: 1.5, 4.0 and 125 deaths per 100 000 among those aged < 5, 5–59 and > 59 years, respectively. Conclusion The highest burden of influenza-associated mortality in Bangladesh in 2009 was among the elderly. PMID:22511823
Inoue, Daisuke; Hinoura, Takuji; Suzuki, Noriko; Pang, Junqin; Malla, Rabin; Shrestha, Sadhana; Chapagain, Saroj Kumar; Matsuzawa, Hiroaki; Nakamura, Takashi; Tanaka, Yasuhiro; Ike, Michihiko; Nishida, Kei; Sei, Kazunari
2015-01-01
Because of heavy dependence on groundwater for drinking water and other domestic use, microbial contamination of groundwater is a serious problem in the Kathmandu Valley, Nepal. This study investigated comprehensively the occurrence of pathogenic bacteria in shallow well groundwater in the Kathmandu Valley by applying DNA microarray analysis targeting 941 pathogenic bacterial species/groups. Water quality measurements found significant coliform (fecal) contamination in 10 of the 11 investigated groundwater samples and significant nitrogen contamination in some samples. The results of DNA microarray analysis revealed the presence of 1-37 pathogen species/groups, including 1-27 biosafety level 2 ones, in 9 of the 11 groundwater samples. While the detected pathogens included several feces- and animal-related ones, those belonging to Legionella and Arthrobacter, which were considered not to be directly associated with feces, were detected prevalently. This study could provide a rough picture of overall pathogenic bacterial contamination in the Kathmandu Valley, and demonstrated the usefulness of DNA microarray analysis as a comprehensive screening tool of a wide variety of pathogenic bacteria.
Bugliosi, Edward F.; Miller, Todd S.; Reynolds, Richard J.
2014-01-01
The lithology, areal extent, and the water-table configuration in stratified-drift aquifers in the northern part of the Pony Hollow Creek valley in the Town of Newfield, New York, were mapped as part of an ongoing aquifer mapping program in Tompkins County. Surficial geologic and soil maps, well and test-boring records, light detection and ranging (lidar) data, water-level measurements, and passive-seismic surveys were used to map the aquifer geometry, construct geologic sections, and determine the depth to bedrock at selected locations throughout the valley. Additionally, water-quality samples were collected from selected streams and wells to characterize the quality of surface and groundwater in the study area. Sedimentary bedrock underlies the study area and is overlain by unstratified drift (till), stratified drift (glaciolacustrine and glaciofluvial deposits), and recent post glacial alluvium. The major type of unconsolidated, water-yielding material in the study area is stratified drift, which consists of glaciofluvial sand and gravel, and is present in sufficient amounts in most places to form an extensive unconfined aquifer throughout the study area, which is the source of water for most residents, farms, and businesses in the valleys. A map of the water table in the unconfined aquifer was constructed by using (1) measurements made between the mid-1960s through 2010, (2) control on the altitudes of perennial streams at 10-foot contour intervals from lidar data collected by Tompkins County, and (3) water surfaces of ponds and wetlands that are hydraulically connected to the unconfined aquifer. Water-table contours indicate that the direction of groundwater flow within the stratified-drift aquifer is predominantly from the valley walls toward the streams and ponds in the central part of the valley where groundwater then flows southwestward (down valley) toward the confluence with the Cayuta Creek valley. Locally, the direction of groundwater flow is radially away from groundwater mounds that have formed beneath upland tributaries that lose water where they flow on alluvial fans on the margins of the valley. In some places, groundwater that would normally flow toward streams is intercepted by pumping wells. Surface-water samples were collected in 2001 at four sites including Carter, Pony Hollow (two sites), and Chafee Creeks, and from six wells throughout the aquifer. Calcium dominates the cation composition and bicarbonate dominates the anion composition in groundwater and surface-water samples and none of the common inorganic constituents collected exceeded any Federal or State water-quality standards. Groundwater samples were collected from six wells all completed in the unconfined sand and gravel aquifer. Concentrations of calcium and magnesium dominated the ionic composition of the groundwater in all wells sampled. Nitrate, orthophosphate, and trace metals were detected in all groundwater samples, but none were more than U.S. Environmental Protection Agency or New York State Department of Health regulatory limits.
NASA Technical Reports Server (NTRS)
Whitehead, Victor S.; Helfert, Michael R.; Lulla, Kamlesh P.; Wood, Charles A.; Amsbury, David L.; Gibson, Robert; Gardner, Guy; Mullane, Mike; Ross, Jerry; Shepherd, Bill
1989-01-01
The earth observations from the STS-27 mission on December 2-6, 1988 are reported. The film and generic scene characteristics chosen for the mission are given. Results are given from geological observations of the Ruwenzori Mountains between Uganda and Zaire, four rift valley systems in Africa and Asia, and several volcanoes and impact craters. Environmental observations of Africa, the Middle East, South Asia, North America and the Soviet Union, are presented. Also, meteorological and oceanographic observations are discussed. The uniqueness of the high-inclination winter launch of the STS-27 mission for obtaining observations of specific features is noted.
Maquart, M; Pascalis, H; Abdouroihamane, S; Roger, M; Abdourahime, F; Cardinale, E; Cêtre-Sossah, C
2016-04-01
Major explosive outbreaks of Rift Valley fever (RVF), an arthropod borne zoonotic disease, occur in humans and animals with significant mortality and economic impact across continental Africa and the Indian Ocean region (Madagascar, the Comoros archipelago). Recently, sporadic human cases have been reported in Mayotte and Grande Comore, two islands belonging to the Comoros archipelago. To identify the hypothetical source of virus introduction in an inter-epidemic or a post-epidemic period, a longitudinal survey of livestock was set up in Comorian ruminant populations, known to be susceptible hosts. The phylogeographic genomic analysis has shown that RVF virus (RVFV) detected in a zebu collected in Anjouan in August 2011 seems to be related to the last known epidemic of RVF which occurred in East Africa and Madagascar (2007-2009). This result highlights the fact that RVFV is maintained within local livestock populations and transboundary animal movements from eastern continental Africa to Indian Ocean islands likely result in RVFV crossover. © 2014 Blackwell Verlag GmbH.
Observations on the epidemiology of Rift Valley fever in Kenya.
Davies, F G
1975-10-01
The epizootic range of Rift Valley fever in Kenya is defined from the results of virus isolations during epizootics, and form an extensive serological survey of cattle which were exposed during an epizootic. A study of the sera from a wide range of wild bovidae sampled immediately after the epizootic, showed that they did not act as reservoir or amplifying hosts for RVF. Virus isolation attempts from a variety of rodents proved negative. Rift Valley fever did not persist between epizootics by producing symptomless abortions in cattle in areas within its epizootic range. A sentinel herd sampled annually after an epizootic in 1968 revealed not one single seroconversion from 1969 to 1974. Certain forest and forest edge situations were postulated as enzootic for Rift Valley fever, and a small percentage of seroconversions were detected in cattle in these areas, born four years after the last epizootic. This has been the only evidence for the persistence of the virus in Kenya since 1968, and may be a part of the interepizootic maintenance cycle for Rift Valley fever in Kenya, which otherwise remains unknown.
NASA Astrophysics Data System (ADS)
Łuszczyńska, Katarzyna; Wistuba, Małgorzata; Malik, Ireneusz
2017-11-01
Intensive development of the area of Polish Carpathians increases the scale of landslide risk. Thus detecting landslide hazards and risks became important issue for spatial planning in the area. We applied dendrochronological methods and GIS analysis for better understanding of landslide activity and related hazards in the test area (3,75 km2): Salomonka valley and nearby slopes in the Beskid Żywiecki Mts., Outer Western Carpathians, southern Poland. We applied eccentricity index of radial growth of trees to date past landslide events. Dendrochronological results allowed us to determine the mean frequency of landsliding at each sampling point which were next interpolated into a map of landslide hazard. In total we took samples at 46 points. In each point we sampled 3 coniferous trees. Landslide hazard map shows a medium (23 sampling points) and low (20 sampling points) level of landslide activity for most of the area. The highest level of activity was recorded for the largest landslide. Results of the dendrochronological study suggest that all landslides reaching downslope to Salomonka valley floor are active. LiDAR-based analysis of relief shows that there is an active coupling between those landslides and river channel. Thus channel damming and formation of an episodic lake are probable. The hazard of flooding valley floor upstream of active landslides should be included in the local spatial planning system and crisis management system.
ANALYSIS OF LOTIC MACROINVERTEBRATE ASSEMBLAGES IN CALIFORNIA'S CENTRAL VALLEY
Using multivariate and cluster analyses, we examined the relaitonships between chemical and physical characteristics and macroinvertebrate assemblages at sites sampled by R-EMAP in California's Central Valley. By contrasting results where community structure was summarized as met...
Preimpoundment water quality of the Wild Rice River, Norman County, Minnesota
Tornes, L.H.
1980-01-01
Water samples have been collected at two sites on the Wild Rice River since September 1974 to establish baseline water-quality characteristics before construction of a reservoir for recreation and flood control near Twin Valley, Minn. A decline in water quality between the sites is shown by mean total phosphorus concentrations, which increase from 0.06 to 0.10 milligram per liter downstream, and mean turbidity, which increases from 12 to 24 units downstream. Phosphorus and ammonia concentrations, as high as 0.31 and 2.7 milligrams per liter, respectively, could be the result of domestic waste input to the river upstream from Hendrum. Biochemical oxygen demand concentrations were significantly higher during spring runoff than during the rest of the year. Four out of 90 bacteria samples taken at Twin Valley indicate the presence of human fecal material, though bacteria densities do not exceed recommendations of the U.S. Environmental Protection Agency for public-water supplies. The dominace of organic-pollution tolerant phytoplankton in 49 out of 78 samples also indicates degradation of the river quality at Twin Valley. Nutrient concentrations at Twin Valley have no apparent effect on phytoplankton concentrations. None of the consitituents sampled were found to exceed recommended concentrations for public-water supplies.
Bonizzi, I; Buffoni, J N; Feligini, M; Enne, G
2009-10-01
To assess the bacterial biodiversity level in bovine raw milk used to produce Fontina, a Protected Designation of Origin cheese manufactured at high-altitude pastures and in valleys of Valle d'Aosta region (North-western Italian Alps) without any starters. To study the relation between microbial composition and pasture altitude, in order to distinguish high-altitude milk against valley and lowland milk. The microflora from milks sampled at different alpine pasture, valley and lowland farms were fingerprinted by PCR of the 16S-23S intergenic transcribed spacers (ITS-PCR). The resulting band patterns were analysed by generalized multivariate statistical techniques to handle discrete (band presence-absence) and continuous (altitude) information. The fingerprints featured numerous bands and marked variability indicating complex, differentiated bacterial communities. Alpine pasture milks were distinguished from lowland ones by cluster analysis, while this technique less clearly discriminated alpine pasture and valley samples. Generalized principal component analysis and clustering-after-ordination enabled a more effective distinction of alpine pasture, valley and lowland samples. Alpine raw milks for Fontina production contain highly diverse bacterial communities, the composition of which is related to the altitude of the pasture where milk was produced. This research may provide analytical support to the important issue represented by the authentication of the geographical origin of alpine milk productions.
Saiki, Michael K.; Palawski, Donald U.
1990-01-01
Concentrations of selenium and other trace elements were determined in 55 whole body samples of juvenile anadromous striped bass (Morone saxatilis) from the San Joaquin Valley and San Francisco Estuary, California. The fish (≤1 yr old—the predominant life stage in the San Joaquin Valley) were collected in September–December 1986 from 19 sites in the Valley and 3 sites in the Estuary, and analyzed for the following elements: aluminum (Al), arsenic (As), boron (B), barium (Ba), beryllium (Be), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), magnesium (Mg), molybdenum (Mo), nickel (Ni), lead (Pb), selenium (Se), strontium (Sr), vanadium (V), and zinc (Zn). When compared to concentrations in whole freshwater fish measured by surveys from other waters, a few samples contained higher levels, of As, Cd, Cu, Pb, and Se. The median concentrations of Al, As, Cu, Fe, Mg, Se, and Sr also differed significantly (P⩽0.05) among sites. However, only Se concentrations were highest (up to 7.9 μg/g dry weight) in samples from Valley sites exposed to agricultural subsurface (tile) drainwater; concentrations were lower in samples collected elsewhere. Water quality variables—especially those strongly influenced by tile drainwater (conductivity, total dissolved solids, total alkalinity, and total hardness)—were also significantly correlated (P⩽0.05) with Se concentrations in fish. Selenium concentrations in striped bass from the Estuary were only one-fourth to one-half the concentrations measured in the most contaminated fish from the San Joaquin River.
Heisig, Paul M.
2004-01-01
Estimates of the quantity and quality of ground-water discharge from valley-fill deposits were calculated for nine valley reaches within the Pepacton watershed in southeastern New York in July and August of 2001. Streamflow and water quality at the upstream and downstream end of each reach and at intervening tributaries were measured under base-flow conditions and used in mass-balance equations to determine quantity and quality of ground-water discharge. These measurements and estimates define the relative magnitudes of upland (tributary inflow) and valley-fill (ground-water discharge) contributions to the main-valley streams and provide a basis for understanding the effects of hydrogeologic setting on these contributions. Estimates of the water-quality of ground-water discharge also provide an indication of the effects of road salt, manure, and human wastewater from villages on the water quality of streams that feed the Pepacton Reservoir. The most common contaminant in ground-water discharge was chloride from road salt; concentrations were less than 15 mg/L.Investigation of ground-water quality within a large watershed by measurement of stream base-flow quantity and quality followed by mass-balance calculations has benefits and drawbacks in comparison to direct ground-water sampling from wells. First, sampling streams is far less expensive than siting, installing, and sampling a watershed-wide network of wells. Second, base-flow samples represent composite samples of ground-water discharge from the most active part of the ground-water flow system across a drainage area, whereas a well network would only be representative of discrete points within local ground-water flow systems. Drawbacks to this method include limited reach selection because of unfavorable or unrepresentative hydrologic conditions, potential errors associated with a large number of streamflow and water-quality measurements, and limited ability to estimate concentrations of nonconservative constituents such as nutrients.The total gain in streamflow from the upper end to the lower end of each valley reach was positively correlated with the annual-runoff volume calculated for the drainage area of the reach. This correlation was not greatly affected by the proportions of ground-water and tributary contributions, except at two reaches that lost much of their tributary flow after the July survey. In these reaches, the gain in total streamflow showed a negative departure from this correlation.Calculated ground-water discharge exceeded the total tributary inflow in each valley reach in both surveys. Groundwater discharge, as a percentage of streamflow gain, was greatest among reaches in wide valleys (about 1,000-ft wide valley floors) that contain permeable valley fill because tributary flows were seasonally diminished or absent as a result of streambed infiltration. Tributary inflows, as a percentage of streamflow gain, were highest in reaches of narrow valleys (200-500-ft wide valley floors) with little valley fill and high annual runoff.Stream-water and ground-water quality were characterized by major-ion type as either (1) naturally occurring water types, relatively unaffected by road salt, or (2) road-salt-affected water types having elevated concentrations of chloride and sodium. The naturally occurring waters were typically the calcium-bicarbonate type, but some contained magnesium and (or) sulfate as secondary ions. Magnesium concentration in base flow is probably related to the amount of till and its carbonate content, or to the amount of lime used on cultivated fields within a drainage area. Sulfate was a defining ion only in dilute waters (with short or unreactive flow paths) with low concentrations of bicarbonate. Nearly all tributary waters were classified as naturally occurring water types.Ground-water discharge from nearly all valley reaches that contain State or county highways had elevated concentrations of chloride and sodsodium. The mean chloride concentrations of ground-water discharge--from 8 to 13 milligrams per liter--did not exceed Federal or State standards, but were about 5 times higher than naturally occurring levels. Application of road salt along a valley bottom probably affects only the shallow ground water in the area between a road and a stream. The elevated concentrations of chloride and sodium in the base-flow samples from such reaches indicate that the concentrations in the affected ground water were high enough to offset the low concentrations in all unaffected ground water entering the reach.Nutrient (nitrate and orthophosphate) concentrations in base-flow samples collected throughout the valleyreach network could not generally be used to estimate their concentrations in ground-water discharge because these constituents can be transformed or removed from water through biological uptake, transformation, or by adsorption on sediments. Base-flow samples from streams with upgradient manure sources or villages served by septic systems consistently had the highest concentrations of these nutrients.
Amick, Benjamin C; Hogg-Johnson, Sheilah; Latour-Villamil, Desiree; Saunders, Ron
2015-12-01
Do Ontario unionized construction firms have lower workers' compensation claims rates compared with nonunion firms? Building trade and construction trade association lists of union contractors were linked to Workplace Safety and Insurance Board claims data for 2006 to 2012. Data were pooled for 2006 to 2012, and negative binomial regressions conducted with adjustment to estimate a union safety effect. The sample included 5797 unionized and 38,626 nonunion construction firms. Total claims rates were 13% higher (1.13, 1.09 to 1.18) in unionized firms because of higher allowed no-lost-time claim rates (1.28, 1.23 to 1.34), whereas the lost-time claims rate was 14% lower (0.86, 0.82 to 0.91). Unionized construction firms compared with nonunion firms have higher no-lost-time and lower lost-time claims rates. Unionized firms may encourage occupational injury reporting and reduce risks through training and hazard identification and control strategies.
Neil, J.M.
1986-01-01
Water samples were collected for selenium analysis from 63 wells in western San Joaquin Valley, California, during February to July 1985. Results of the data collection indicate that dissolved selenium concentrations ranged from less than 1 to 120 micrograms per liter; more than 50 percent of the wells sampled had concentrations of less than 1 microgram per liter. Four additional samples collected from public supply wells in the western valley had concentrations ranging from less than 1 to 2 micrograms per liter. All samples from five public supply wells east of the study area had concentrations less than 1 microgram per liter. The U.S. Environmental Protection Agency 's drinking-water standard of 10 micrograms per liter for selenium was slightly exceeded in 2 of 39 domestic wells (11 and 13 micrograms per liter) and substantially exceeded in 2 of 11 irrigation and agricultural wells (55 and 120 micrograms per liter). (USGS)
Zabik, John M.; Seiber, James N.
1993-01-01
Atmospheric transport of organophosphate pesticides from California's Central Valley to the Sierra Nevada mountains was assessed by collecting air- and wet-deposition samples during December, January, February, and March, 1990 to 1991. Large-scale spraying of these pesticides occurs during December and January to control insect infestations in valley orchards. Sampling sites were placed at 114- (base of the foothills), 533-, and 1920-m elevations. Samples acquired at these sites contained chlorpyrifos [phosphorothioic acid; 0,0-diethyl 0-(3,5,6-trichloro-2-pyridinyl) ester], parathion [phosphorothioic acid, 0-0-diethylo-(4-nitrophenyl) ester], diazinon {phosphorothioic acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester} diazinonoxon {phosphoric acid, 0,0-diethyl 0-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] ester}, and paraoxon [phosphoric acid, 0,0-diethyl 0-(4-nitrophenyl) ester] in both air and wet deposition samples. Air concentrations of chloropyrifos, diazinon and parathion ranged from 13 to 13 000 pg/m3 at the base of the foothills. At 533-m air concentrations were below the limit of quantification (1.4 pg/m3) to 83 pg/m3 and at 1920 m concentrations were below the limit of quantification. Concentrations in wet deposition varied with distance and elevation from the Central Valley. Rainwater concentrations at the base of the foot hills ranged from 16 to 7600 pg/mL. At 533-m rain and snow water concentrations ranged from below the limit of quantification (1.3 pg/mL) to 140 pg/mL and at 1920 m concentrations ranged from below the limit of quantification to 48 pg/mL. These findings indicate that atmospheric transport of pesticides applied in the valley to the Sierra Nevada mountains is occurring, but the levels decrease as distance and elevation increase from the valley floor.
Kamalzadeh, Zahra; Babanezhad, Esmaeil; Ghaffari, Solmaz; Mohseni Ezhiyeh, Alireza; Mohammadnejad, Mahdieh; Naghibfar, Mehdi; Bararjanian, Morteza; Attar, Hossein
2017-08-01
A new, normal phase high performance liquid chromatography (NP-HPLC) method was developed for separation of Bortezomib (BZB) enantiomers and quantitative determination of (1S,2R)-enantiomer of BZB in active pharmaceutical ingredient (API) samples. The developed method was validated based on International Conference on Harmonisation (ICH) guidelines and it was proved to be accurate, precise and robust. The obtained resolution (RS) between the enantiomers was more than 2. The calibration curve for (1S,2R)-enantiomer was found to be linear in the concentration range of 0.24-5.36 mg/L with regression coefficient (R2) of 0.9998. Additionally, the limit of detection (LOD) and limit of quantification (LOQ) were 0.052 and 0.16 mg/L, respectively. Also, in this study, a precise, sensitive and robust gradient reversed-phase HPLC (RP-HPLC) method was developed and validated for determination of BZB in API samples. The detector response was linear over the concentration range of 0.26-1110.5 mg/L. The values of R2, LOD and LOQ were 0.9999, 0.084 and 0.25 mg/L, respectively. For both NP-HPLC and RP-HPLC methods, all of the RSD (%) values obtained in the precision study were <1.0%. System suitability parameters in terms of tailing factor (TF), number of theoretical plates (N) and RS were TF < 2.0, N > 2,000 and RS > 2.0. The performance of two common integration methods of valley to valley and drop perpendicular for drawing the baseline between two adjacent peaks were investigated for the determination of diastereomeric impurity (Imp-D) in the BZB-API samples. The results showed that the valley to valley method outperform the drop perpendicular method for calculation of Imp-D peak areas. Therefore, valley to valley method was chosen for peak integration. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Hans-Erik Andersen; Jacob Strunk; Hailemariam Temesgen
2011-01-01
Airborne laser scanning, collected in a sampling mode, has the potential to be a valuable tool for estimating the biomass resources available to support bioenergy production in rural communities of interior Alaska. In this study, we present a methodology for estimating forest biomass over a 201,226-ha area (of which 163,913 ha are forested) in the upper Tanana valley...
Fuel regulation in inland navigation: reduced soil black carbon and PAH deposition in river valleys
NASA Astrophysics Data System (ADS)
Bläsing, M.; Schwark, L.; Amelung, W.; Lehndorff, E.
2016-12-01
Inland navigation (IN) is of increasing importance in the transport sector. Most inland waterways and inland ports are located in/near urban regions; hence many people are exposed to emissions from IN. However, its contribution to environmental quality is not yet known. Accordingly, we aimed at identifying IN emissions in the environment, and investigating consequences of the S-reduction in ship diesel (EU regulation 2009/30/EC) on IN emissions. To do so, topsoil samples were taken from vineyards in valley transects (perpendicular to rivers) at two German inland waterways (Rhine, Moselle) and one ship-free reference valley (Ahr) and analyzed for polycyclic aromatic hydrocarbons (PAHs) and black carbon (BC). To elucidate the effect of fuel regulation (effective since 2011), samplings were performed from 2010 to 2013. Additionally, the potential dispersal of IN emissions was simulated by a Lagrangian stochastic model. Before regulating the S-content of ship diesel by the EU directive soil samples indicated a clear impact of IN emissions on BC and PAH deposits, in at least 200 and 350 m distance to the Moselle and Rhine river, respectively. IN emissions accounted for approximately 30% of total soil BC. However, soils along waterways comprised only slightly more BC than soils in the ship-free Ahr Valley, with BC contents comparable to rural to suburban European soils. Contents of PAHs in river valleys compared to remote to urban pollution load. In the course of the fuel regulation, BC and PAH deposits in soil were reduced within three years by 30-60%, respectively. Also the quality of emissions changed to higher shares of low molecular weight PAHs and smaller proportions of soot-BC, indicating less deposition of IN emissions. The impact of the fuel regulation was more obvious at the Rhine Valley than at the Moselle Valley, likely because of higher ship traffic volume at the former. Overall, fuel regulation was effective in reducing IN emissions along inland waterways.
2D Semiconductors for Valley-Polarized LEDs and Photodetectors
NASA Astrophysics Data System (ADS)
Yu, Ting
The recently discovered two-dimensional (2D) semiconductors, such as transitional-metal-dichalcogenide monolayers, have aroused great interest due to the underlying quantum physics and the appealing optoelectronic applications like atomically thin light-emitting diodes (LEDs) and photodetectors. On the one hand, valley-polarized electroluminescence and photocurrent from such monolayers have not caused enough attention but highly demanded as building blocks for the new generation valleytronic applications. On the other hand, most reports on these devices are based on the mechanically exfoliated small samples. Considering real applications, a strategy which could offer mass-product and high compatibility to the current planar processes is greatly demanded. Large-area samples prepared by chemical vapour deposition (CVD) are perfect candidates towards such a goal. Here, we report electrically tunable valley-polarized electroluminescence and the selective spin-valley-coupled photocurrent in optoelectronic devices based on monolayer WS2 and MoS2 grown by CVD, exhibiting large electroluminescence and photocurrent dichroisms of 81% and 60%, respectively. The controllable valley polarization and emission components of the electroluminescence have been realized by varying electrical injection of carriers. For the observed helicity-dependent photocurrent, the circular photogalvanic effect at resonant excitations has been found to take the dominant responsibility.
Mastalerz, Maria; Bustin, R.M.
1997-01-01
Variations in elemental and molecular chemistry of macerals, with vitrinite, semifusinite and sporinite in particular, are discussed for the coal seams of the Mist Mountain Formation in the Elk Valley coalfield, in western Canada. In the south Elk Valley coalfield, carbon content of vitrinite oscillates around 85%, and oxygen content increases gradually up section, from seam A to C. In the north Elk Valley coalfield, carbon content in vitrinite shows marked variations (from 70% to 85%) between the samples and is lower than in the south Elk Valley coalfield, which is consistent with a higher maturation level of south Elk Valley coalfield samples. Sulphur content is below 1% in both coalfields. Semifusinite, in general, has higher carbon and lower oxygen content than vitrinite, whereas cutinite has higher carbon content than vitrinite and slightly higher or comparable to that of semifusinite. Functional group distributions show large variations between the seams and these variations are attributed mainly to differences in a primary depositional environment and only occasionally to later weathering and oxidation processes. The results presented in this paper provide also information on the length and branching of aliphatic chains, which, for liptinite macerals is valuable from the oil generation viewpoint, whereas for semifusinite, it may help to understand reactive versus non-reactive behaviour during coking.
NASA Astrophysics Data System (ADS)
Lundquist, J. K.; Bariteau, L.; Hocut, C. M.; Creegan, E.; Chow, F. K.; Mazzaro, L.; Bodini, N.; Tomaszewski, J.; Murphy, P.; Neher, J.; van Veen, L.; Pattantyus, A.
2017-12-01
To investigate the turbulent mixing events within and around Portugal's Perdigão valley during the intensive field campaign of 1 May - 15 June 2017, the University of Colorado Boulder (CU) and the Army Research Laboratory (ARL) deployed Tethered Lifting Systems (TLS). The TLS carried turbulence probes to sample from the ground to 500 m above the surface. These probes sample temperature, relative humidity, and winds, including very high-rate measurements that enable measurement of turbulence dissipation rate and temperature structure parameters. The vertical resolution of the systems is defined by the ascent and descent rates of the probes, making this platform uniquely suited for sensing and characterizng stratification and layering undetectable by other instrumentation in the campaign. Therefore, the detailed information provided by the TLS (see Figure 1) allows us to characterize the intermittent turbulence events and circulations above and within the valley with detail sufficient for evaluation of mesoscale-microscale modeling of these flows. This presentation will survey the datasets collected by the University of Colorado's TLS located in the center of the valley. Specific case studies will be highlighted, including turbine wake measurements, interactions between drainage flow down-valley and mesoscale forcing up-valley, evening transitions, and morning transitions. Several coordinated "flights" of the CU and ARL systems within and outside of the valley enabled contrasting measurements to provide insight into the terrain-driven mixing events.
Huntington, Jena M.; Garcia, C. Amanda; Rosen, Michael R.
2014-01-01
Dixie Valley, a primarily undeveloped basin in west-central Nevada, is being considered for groundwater exportation. Proposed pumping would occur from the basin-fill aquifer. In response to proposed exportation, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation and Churchill County, conducted a study to improve the understanding of groundwater resources in Dixie Valley. The objective of this report is to characterize the hydrogeologic framework, the occurrence and movement of groundwater, the general water quality of the basin-fill aquifer, and the potential mixing between basin-fill and geothermal aquifers in Dixie Valley. Various types of geologic, hydrologic, and geochemical data were compiled from previous studies and collected in support of this study. Hydrogeologic units in Dixie Valley were defined to characterize rocks and sediments with similar lithologies and hydraulic properties influencing groundwater flow. Hydraulic properties of the basin-fill deposits were characterized by transmissivity estimated from aquifer tests and specific-capacity tests. Groundwater-level measurements and hydrogeologic-unit data were combined to create a potentiometric surface map and to characterize groundwater occurrence and movement. Subsurface inflow from adjacent valleys into Dixie Valley through the basin-fill aquifer was evaluated using hydraulic gradients and Darcy flux computations. The chemical signature and groundwater quality of the Dixie Valley basin-fill aquifer, and potential mixing between basin-fill and geothermal aquifers, were evaluated using chemical data collected from wells and springs during the current study and from previous investigations. Dixie Valley is the terminus of the Dixie Valley flow system, which includes Pleasant, Jersey, Fairview, Stingaree, Cowkick, and Eastgate Valleys. The freshwater aquifer in the study area is composed of unconsolidated basin-fill deposits of Quaternary age. The basin-fill hydrogeologic unit can be several orders of magnitude more transmissive than surrounding and underlying consolidated rocks and Dixie Valley playa deposits. Transmissivity estimates in the basin fill throughout Dixie Valley ranged from 30 to 45,500 feet squared per day; however, a single transmissivity value of 0.1 foot squared per day was estimated for playa deposits. Groundwater generally flows from the mountain range uplands toward the central valley lowlands and eventually discharges near the playa edge. Potentiometric contours east and west of the playa indicate that groundwater is moving eastward from the Stillwater Range and westward from the Clan Alpine Mountains toward the playa. Similarly, groundwater flows from the southern and northern basin boundaries toward the basin center. Subsurface groundwater flow likely enters Dixie Valley from Fairview and Stingaree Valleys in the south and from Jersey and Pleasant Valleys in the north, but groundwater connections through basin-fill deposits were present only across the Fairview and Jersey Valley divides. Annual subsurface inflow from Fairview and Jersey Valleys ranges from 700 to 1,300 acre-feet per year and from 1,800 to 2,300 acre-feet per year, respectively. Groundwater flow between Dixie, Stingaree, and Pleasant Valleys could occur through less transmissive consolidated rocks, but only flow through basin fill was estimated in this study. Groundwater in the playa is distinct from the freshwater, basin-fill aquifer. Groundwater mixing between basin-fill and playa groundwater systems is physically limited by transmissivity contrasts of about four orders of magnitude. Total dissolved solids in playa deposit groundwater are nearly 440 times greater than total dissolved solids in the basin-fill groundwater. These distinctive physical and chemical flow restrictions indicate that groundwater interaction between the basin fill and playa sediments was minimal during this study period (water years 2009–11). Groundwater in Dixie Valley generally can be characterized as a sodium bicarbonate type, with greater proportions of chloride north of the Dixie Valley playa, and greater proportions of sulfate south of the playa. Analysis of major ion water chemistry data sampled during the study period indicates that groundwater north and south of Township 22N differ chemically. Dixie Valley groundwater quality is marginal when compared with national primary and secondary drinking-water standards. Arsenic and fluoride concentrations exceed primary drinking water standards, and total dissolved solids and manganese concentrations exceed secondary drinking water standards in samples collected during this study. High concentrations of boron and tungsten also were observed. Chemical comparisons between basin-fill and geothermal aquifer water indicate that most basin-fill groundwater sampled could contain 10–20 percent geothermal water. Geothermal indicators such as high temperature, lithium, boron, chloride, and silica suggest that mixing occurs in many wells that tap the basin-fill aquifer, particularly on the north, south, and west sides of the basin. Magnesium-lithium geothermometers indicate that some basin-fill aquifer water sampled for the current study likely originates from water that was heated above background mountain-block recharge temperatures (between 3 and 15 degrees Celsius), highlighting the influence of mixing with warm water that was possibly derived from geothermal sources.
Local Clerical and Custodial Wage Administration Practices.
ERIC Educational Resources Information Center
Bakos, Estelle
Moraine Valley Community College (MVCC), Illinois, collected salary-related data for clerical and custodial personnel, in order to establish a compatible wage structure, provide business management course information, and improve secretarial career counseling. Limiting data sampling to the geographical boundries of the Moraine Valley District…
Valley-chiral quantum Hall state in graphene superlattice structure
NASA Astrophysics Data System (ADS)
Tian, H. Y.; Tao, W. W.; Wang, J.; Cui, Y. H.; Xu, N.; Huang, B. B.; Luo, G. X.; Hao, Y. H.
2016-05-01
We theoretically investigate the quantum Hall effect in a graphene superlattice (GS) system, in which the two valleys of graphene are coupled together. In the presence of a perpendicular magnetic field, an ordinary quantum Hall effect is found with the sequence σxy=ν e^2/h(ν=0,+/-1,+/-2,\\cdots) . At the zeroth Hall platform, a valley-chiral Hall state stemming from the single K or K' valley is found and it is localized only on one sample boundary contributing to the longitudinal conductance but not to the Hall conductivity. Our findings may shed light on the graphene-based valleytronics applications.
Geochemical evidence for diversity of dust sources in the southwestern United States
Reheis, M.C.; Budahn, J.R.; Lamothe, P.J.
2002-01-01
Several potential dust sources, including generic sources of sparsely vegetated alluvium, playa deposits, and anthropogenic emissions, as well as the area around Owens Lake, California, affect the composition of modern dust in the southwestern United States. A comparison of geochemical analyses of modern and old (a few thousand years) dust with samples of potential local sources suggests that dusts reflect four primary sources: (1) alluvial sediments (represented by Hf, K, Rb, Zr, and rare-earth elements, (2) playas, most of which produce calcareous dust (Sr, associated with Ca), (3) the area of Owens (dry) Lake, a human-induced playa (As, Ba, Li, Pb, Sb, and Sr), and (4) anthropogenic and/or volcanic emissions (As, Cr, Ni, and Sb). A comparison of dust and source samples with previous analyses shows that Owens (dry) Lake and mining wastes from the adjacent Cerro Gordo mining district are the primary sources of As, Ba, Li, and Pb in dusts from Owens Valley. Decreases in dust contents of As, Ba, and Sb with distance from Owens Valley suggest that dust from southern Owens Valley is being transported at least 400 km to the east. Samples of old dust that accumulated before European settlement are distinctly lower in As, Ba, and Sb abundances relative to modern dust, likely due to modern transport of dust from Owens Valley. Thus, southern Owens Valley appears to be an important, geochemically distinct, point source for regional dust in the southwestern United States. Copyright ?? 2002 Elsevier Science Ltd.
Rockfall hazard and risk assessment in the Yosemite Valley, California, USA
Guzzetti, F.; Reichenbach, P.; Wieczorek, G.F.
2003-01-01
Rock slides and rock falls are the most frequent types of slope movements in Yosemite National Park, California. In historical time (1857-2002) 392 rock falls and rock slides have been documented in the valley, and some of them have been mapped in detail. We present the results of an attempt to assess rock fall hazards in the Yosemite Valley. Spatial and temporal aspects of rock falls hazard are considered. A detailed inventory of slope movements covering the 145-year period from 1857 to 2002 is used to determine the frequency-volume statistics of rock falls and to estimate the annual frequency of rock falls, providing the temporal component of rock fall hazard. The extent of the areas potentially subject to rock fall hazards in the Yosemite Valley were obtained using STONE, a physically-based rock fall simulation computer program. The software computes 3-dimensional rock fall trajectories starting from a digital elevation model (DEM), the location of rock fall release points, and maps of the dynamic rolling friction coefficient and of the coefficients of normal and tangential energy restitution. For each DEM cell the software calculates the number of rock falls passing through the cell, the maximum rock fall velocity and the maximum flying height. For the Yosemite Valley, a DEM with a ground resolution of 10 ?? 10 m was prepared using topographic contour lines from the U.S. Geological Survey 1:24 000-scale maps. Rock fall release points were identified as DEM cells having a slope steeper than 60??, an assumption based on the location of historical rock falls. Maps of the normal and tangential energy restitution coefficients and of the rolling friction coefficient were produced from a surficial geologic map. The availability of historical rock falls mapped in detail allowed us to check the computer program performance and to calibrate the model parameters. Visual and statistical comparison of the model results with the mapped rock falls confirmed the accuracy of the model. The model results are compared with a previous map of rockfall talus and with a geomorphic assessment of rock fall hazard based on potential energy referred to as a shadow angle approach, recently completed for the Yosemite Valley. The model results are then used to identify the roads and trails more subject to rock fall hazard. Of the 166.5 km of roads and trails in the Yosemite Valley 31.2% were found to be potentially subject to rock fall hazard, of which 14% are subject to very high hazard. ?? European Geosciences Union 2003.
Hans-Erik Andersen; Jacob Strunk; Hailemariam Temesgen
2011-01-01
Airborne laser scanning, collected in a sampling mode, has the potential to be a valuable tool for estimating the biomass resources available to support bioenergy production in rural communities of interior Alaska. In this study, we present a methodology for estimating forest biomass over a 201,226-ha area (of which 163,913 ha are forested) in the upper Tanana valley...
Welch, Heather L.; Kingsbury, James A.; Tollett, Roland W.; Seanor, Ronald C.
2009-01-01
The Mississippi embayment-Texas coastal uplands aquifer system is an important source of drinking water, providing about 724 million gallons per day to about 8.9 million people in Texas, Louisiana, Mississippi, Arkansas, Missouri, Tennessee, Kentucky, Illinois, and Alabama. The Mississippi River Valley alluvial aquifer ranks third in the Nation for total withdrawals of which more than 98 percent is used for irrigation. From 1994 through 2004, water-quality samples were collected from 169 domestic, monitoring, irrigation, and public-supply wells in the Mississippi embayment-Texas coastal uplands aquifer system and the Mississippi River Valley alluvial aquifer in various land-use settings and of varying well capacities as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Groundwater samples were analyzed for physical properties and about 200 water-quality constituents, including total dissolved solids, major inorganic ions, trace elements, radon, nutrients, dissolved organic carbon, pesticides, pesticide degradates, and volatile organic compounds. The occurrence of nutrients and pesticides differed among four groups of the 114 shallow wells (less than or equal to 200 feet deep) in the study area. Tritium concentrations in samples from the Holocene alluvium, Pleistocene valley trains, and shallow Tertiary wells indicated a smaller component of recent groundwater than samples from the Pleistocene terrace deposits. Although the amount of agricultural land overlying the Mississippi River Valley alluvial aquifer was considerably greater than areas overlying parts of the shallow Tertiary and Pleistocene terrace deposits wells, nitrate was rarely detected and the number of pesticides detected was lower than other shallow wells. Nearly all samples from the Holocene alluvium and Pleistocene valley trains were anoxic, and the reducing conditions in these aquifers likely result in denitrification of nitrate. In contrast, most samples from the Pleistocene terrace deposits in Memphis, Tennessee, were oxic, and the maximum nitrate concentration measured was 6.2 milligrams per liter. Additionally, soils overlying the Holocene alluvium and Pleistocene valley trains, generally in areas near the wells, had lower infiltration rates and higher percentages of clay than soils overlying the shallow Tertiary and Pleistocene terrace deposits wells. Differences in these soil properties were associated with differences in the occurrence of pesticides. Pesticides were most commonly detected in samples from wells in the Pleistocene terrace deposits, which generally had the highest infiltration rates and lowest clay content. Median dissolved phosphorus concentrations were 0.07, 0.11, and 0.65 milligram per liter in samples from the shallow Tertiary, Pleistocene valley trains, and Holocene alluvium, respectively. The widespread occurrence of dissolved phosphorus at concentrations greater than 0.02 milligram per liter suggests either a natural source in the soils or aquifer sediments, or nonpoint sources such as fertilizer and animal waste or a combination of natural and human sources. Although phosphorus concentrations in samples from the Holocene alluvium were weakly correlated to concentrations of several inorganic constituents, elevated concentrations of phosphorus could not be attributed to a specific source. Phosphorus concentrations generally were highest where samples indicated anoxic and reducing conditions in the aquifers. Elevated dissolved phosphorus concentrations in base-flow samples from two streams in the study area suggest that transport of phosphorus with groundwater is a potential source contributing to high yields of phosphorus in the lower Mississippi River basin. Water from 55 deep wells (greater than 200 feet deep) completed in regional aquifers of Tertiary age represent a sample of the principal aquifers used for drinking-water supply in the study area. The wells were screened in both confined and
The relationship between labor unions and safety in US airlines: Is there a "union effect?"
NASA Astrophysics Data System (ADS)
Zapf, Renee Catherine
Every airline union claims to work for safety and presents anecdotes where greater airline safety has been achieved through union efforts. The effect unionization has on safety outcomes in U.S. commercial airlines, however, wasn't found to be previously tested. Studies have shown that in industries such as coal mining, retail, and construction, unionization does lead to an increase in safety. This study evaluated the safety rates of 15 major US commercial airlines to compare the difference between unionized and non-unionized airlines. These safety rates were compared based on if and how long each airline's pilots and flight attendants have been unionized, to determine if unionization had an effect on safety outcomes. The 15 airlines included in the study identified as operating most of the years between 1990 and 2013, with annual departures averaging over 130,000, available through the Bureau of Transportation Statistics. Accident and Incident information was acquired through the National Transportation Safety Board database. The number of accident and incidents divided by the total departures at each airline was used as the safety rate. Union websites provided information on unionization at the airlines. Due to the complex nature of the aviation industry, a number of confounding factors could have affected the tests, including mergers, route structures, and legislation. To help control for these confounding factors, this study was limited to airlines with a stable presence in the industry over time, which limited the number of airlines included. No significant difference was found between unionized and non-unionized airlines in this study, though the mean safety rate of unionized airlines was found be better than non-unionized airlines. This study did not take into account safety improvements that were union-backed and eventually required at all airlines, regardless of unionization. Due to the large sample size of the small population the difference in safety rate means could be indicative of greater safety in unionized airlines.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moser, Duane P.; Hamilton-Brehm, Scott D.; Fisher, Jenny C.
Due to the legacy of Cold War nuclear weapons testing, the Nevada National Security Site (NNSS, formerly known as the Nevada Test Site (NTS)) contains millions of Curies of radioactive contamination. Presented here is a summary of the results of the first comprehensive study of subsurface microbial communities of radioactive and nonradioactive aquifers at this site. To achieve the objectives of this project, cooperative actions between the Desert Research Institute (DRI), the Nevada Field Office of the National Nuclear Security Administration (NNSA), the Underground Test Area Activity (UGTA), and contractors such as Navarro-Interra (NI), were required. Ultimately, fluids from 17more » boreholes and two water-filled tunnels were sampled (sometimes on multiple occasions and from multiple depths) from the NNSS, the adjacent Nevada Test and Training Range (NTTR), and a reference hole in the Amargosa Valley near Death Valley. The sites sampled ranged from highly-radioactive nuclear device test cavities to uncontaminated perched and regional aquifers. Specific areas sampled included recharge, intermediate, and discharge zones of a 100,000-km2 internally-draining province, known as the Death Valley Regional Flow System (DVRFS), which encompasses the entirety of the NNSS/NTTR and surrounding areas. Specific geological features sampled included: West Pahute and Ranier Mesas (recharge zone), Yucca and Frenchman Flats (transitional zone), and the Western edge of the Amargosa Valley near Death Valley (discharge zone). The original overarching question underlying the proposal supporting this work was stated as: Can radiochemically-produced substrates support indigenous microbial communities and subsequently stimulate biocolloid formation that can affect radionuclides in NNSS subsurface nuclear test/detonation sites? Radioactive and non-radioactive groundwater samples were thus characterized for physical parameters, aqueous geochemistry, and microbial communities using both DNA- and cultivation-based tools in an effort to understand the drivers of microbial community structure (including radioactivity) and microbial interactions with select radionuclides and other factors across the range of habitats surveyed.« less
Heisig, Paul M.; Scott, Tia-Marie
2013-01-01
A survey of methane in groundwater was undertaken to document methane occurrence on the basis hydrogeologic setting within a glaciated 1,810-square-mile area of south-central New York along the Pennsylvania border. Sixty-six wells were sampled during the summer of 2012. All wells were at least 1 mile from any known gas well (active, exploratory, or abandoned). Results indicate strong positive and negative associations between hydrogeologic settings and methane occurrence. The hydrogeologic setting classes are based on topographic position (valley and upland), confinement or non-confinement of groundwater by glacial deposits, well completion in fractured bedrock or sand and gravel, and hydrogeologic subcategories. Only domestic wells and similar purposed supply wells with well-construction and log information were selected for classification. Field water-quality characteristics (pH, specific conductance, dissolved oxygen, and temperature) were measured at each well, and samples were collected and analyzed for dissolved gases, including methane and short-chain hydrocarbons. Carbon and hydrogen isotopic ratios of methane were measured in 21 samples that had at least 0.3 milligram per liter (mg/L) of methane. Results of sampling indicate that occurrence of methane in groundwater of the region is common—greater than or equal to 0.001 mg/L in 78 percent of the groundwater samples. Concentrations of methane ranged over five orders of magnitude. Methane concentrations at which monitoring or mitigation are indicated (greater than or equal to 10 mg/L) were measured in 15 percent of the samples. Methane concentrations greater than 0.1 mg/L were associated with specific hydrogeologic settings. Wells completed in bedrock within valleys and under confined groundwater conditions were most closely associated with the highest methane concentrations. Fifty-seven percent of valley wells had greater than or equal to 0.1 mg/L of methane, whereas only 10 percent of upland wells equaled or exceeded that concentration. Isotopic signatures differed between these groups as well. Methane in valley wells was predominantly thermogenic in origin, likely as a result of close vertical proximity to underlying methane-bearing saline groundwater and brine and possibly as a result of enhanced bedrock fracture permeability beneath valleys that provides an avenue for upward gas migration. Isotopic signatures of methane from four upland well samples indicated a microbial origin (carbon-dioxide reduction) with one sample possibly altered by microbial methane oxidation. Water samples from wells in a valley setting that indicate a mix of thermogenic and microbial methane reflect the close proximity of regional groundwater flow and underlying saline water and brine in valley areas. The microbial methane is likely produced by bacteria that utilize carbon dioxide or formational organic matter in highly reducing environments within the subregional groundwater flow system. This characterization of groundwater methane shows the importance of subsurface information (hydrogeology, well construction) in understanding methane occurrence and provides an initial conceptual framework that can be utilized in investigation of stray gas in south-central New York.
Wiley, Jeffrey B.; Evaldi, Ronald D.; Eychaner, James H.; Chambers, Douglas B.
2001-01-01
The effects of mountaintop removal coal mining and the valley fills created by this mining method in southern West Virginia were investigated by comparing data collected at valley-fill, mined, and unmined sites. Bed material downstream of valley-fill sites had a greater number of particles less than 2 millimeters and a smaller median particle size than the mined and unmined sites. At the 84th percentile of sampled data, however, bed material at each site type had about the same size particles. Bankfull cross-sectional areas at a riffle section were approximately equal at valley-fill and unmined sites, but not enough time has passed and insufficient streamflows since the land was disturbed may have prevented the stream channel at valley-fill sites from reaching equilibrium. The 90-percent flow durations at valley-fill sites generally were 6-7 times greater than at unmined sites. Some valley-fill sites, however, exhibited streamflows similar to unmined sites, and some unmined sites exhibited streamflows similar to valley-fill sites. Daily streamflows from valley-fill sites generally are greater than daily streamflows from unmined sites during periods of low streamflow. Valley-fill sites have a greater percentage of base-flow and a lower percentage of flow from storm runoff than unmined sites. Water temperatures from a valley-fill site exhibited lower daily fluctuations and seasonal variations than water temperatures from an unmined site.
Seasonal trend of fog water chemical composition in the Po Valley.
Fuzzi, S; Facchini, M C; Orsi, G; Ferri, D
1992-01-01
Fog frequency in the Po Valley, Northern Italy, can be as high as 30% of the time in the fall-winter season. High pollutant concentrations have been measured in fog water samples collected in this area over the past few years. The combined effects of high fog occurrence and high pollutant loading of the fog droplets can determine, in this area, appreciable chemical deposition rates. An automated station for fog water collection was developed, and deployed at the field station of S. Pietro Capofiume, in the eastern part of the Po Valley for an extended period: from the beginning of November 1989 to the end of April 1990. Time-resolved sampling of fog droplets was carried out during all fog events occurring in this period, and chemical analyses were performed on the collected samples. Statistical information on fog occurrence and fog water chemical composition is reported in this paper, and a tentative seasonal deposition budget is calculated for H+, NH4+, NO3- and SO4(2-) ions. The problems connected with fog droplet sampling in sub-freezing conditions are also addressed in the paper.
Long-term fault creep observations in central California
NASA Astrophysics Data System (ADS)
Schulz, Sandra S.; Mavko, Gerald M.; Burford, Robert O.; Stuart, William D.
1982-08-01
The U.S. Geological Survey (USGS) has been monitoring aseismic fault slip in central California for more than 10 years as part of an earthquake prediction experiment. Since 1968, the USGS creep network has grown from one creep meter at the Cienega Winery south of Hollister to a 44-station network that stretches from Hayward, east of San Francisco Bay, to Palmdale in southern California. In general, the long-term slip pattern is most variable on sections of the faults where several magnitude 4 and larger earthquakes occurred during the recording period (e.g., Calaveras fault near Hollister and San Andreas fault between San Juan Bautista and Bear Valley). These fault sections are the most difficult to characterize with a single long-term slip rate. In contrast, sections of the faults that are seismically relatively quiet (e.g., San Andreas fault between Bear Valley and Parkfield) produce the steadiest creep records and are easiest to fit with a single long-term slip rate. Appendix is available with entire article on microfiche. Order from the American Geophysical Union, 2000 Florida Avenue, N.W., Washington, D.C. 20009. Document J82-004; $1.00. Payment must accompany order.
One year of tracer dispersion measurements over Washington, D.C.
NASA Astrophysics Data System (ADS)
Draxler, Roland R.
Two perfluorocarbon tracers were released for 6 h from several locations about 20 km outside of Washington, D.C. at 36-h intervals for over 1 year. Continuous air samples were collected at 8-h intervals at one urban and two suburban sites, and at monthly intervals at 93 sites all over the region. Over 50 % of the 8-h samples showed no tracer concentration. However, about 20% of the samples had significant amounts of tracer, so that about 600 values under a variety of meteorological conditions are available for analysis. Although the Potomac River is only 100 m below the surrounding terrain, the tracer releases from within the river valley indicated that the tracer flow was channeled along the river valley. For tracer released away from the river valley, the tracer tended to pass aloft and not mix down into the river valley. Sequential concentration measurements frequently showed high values for extended periods after the tracer release terminated, decreasing exponentially with a half life of about 3 h. This suggests that the finite tracer plume may have a rather long upwind trailing edge toward the release point. The average rate of change in the vertical dispersion during summer and winter was found to be proportional to the 0.6 power of distance.
NASA Astrophysics Data System (ADS)
Gillies, S. L.; Marsh, S. J.; Peucker-Ehrenbrink, B.; Janmaat, A.; Bourdages, M.; Paulson, D.; Groeneweg, A.; Bogaerts, P.; Robertson, K.; Clemence, E.; Smith, S.; Yakemchuk, A.; Faber, A.
2017-12-01
Undergraduate students in the Geography and Biology Departments at the University of the Fraser Valley (UFV) have been provided the opportunity to participate in the time series sampling of the Fraser River at Fort Langley and Fraser Valley tributaries as part of the Global Rivers Observatory (GRO, www.globalrivers.org) which is coordinated by Woods Hole Oceanographic Institution and Woods Hole Research Center. Student research has focussed on Clayburn, Willband and Stoney Creeks that flow from Sumas Mountain northwards to the Fraser River. These watercourses are increasingly being impacted by anthropogenic activity including residential developments, industrial activity, and agricultural landuse. Students are instructed in field sampling protocols and the collection of water chemistry data and the care and maintenance of the field equipment. Students develop their own research projects and work in support of each other as teams in the field to collect the data and water samples. Students present their findings as research posters at local academic conferences and at UFV's Student Research Day. Through their involvement in our field research our students have become more aware of the state of our local streams, the methods used to monitor water chemistry and how water chemistry varies seasonally.
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.
Socioeconomic Status and Unionization Attitudes in the United States.
ERIC Educational Resources Information Center
Cornfield, Daniel B.; Kim, Hyunhee
1994-01-01
Survey responses from a national sample of 1,195 nonunion, nonfarm workers suggest that corporations legitimize themselves by appealing to occupational identities of high-status workers, whereas unions legitimize themselves by appealing to social background identities (ethnic, racial, and gender identities) of low-status workers. Prounion…
Valley-controlled propagation of pseudospin states in bulk metacrystal waveguides
NASA Astrophysics Data System (ADS)
Chen, Xiao-Dong; Deng, Wei-Min; Lu, Jin-Cheng; Dong, Jian-Wen
2018-05-01
Light manipulations such as spin-direction locking propagation, robust transport, quantum teleportation, and reconfigurable electromagnetic pathways have been investigated at the boundaries of photonic systems. Recently by breaking Dirac cones in time-reversal-invariant photonic crystals, valley-pseudospin coupled edge states have been employed to realize selective propagation of light. Here, we realize the controllable propagation of pseudospin states in three-dimensional bulk metacrystal waveguides by valley degree of freedom. Reconfigurable photonic valley Hall effect is achieved for frequency-direction locking propagation in such a way that the propagation path can be tunable precisely by scanning the working frequency. A complete transition diagram is illustrated on the valley-dependent pseudospin states of Dirac-cone-absent photonic bands. A photonic blocker is proposed by cascading two inversion asymmetric metacrystal waveguides in which pseudospin-direction locking propagation exists. In addition, valley-dependent pseudospin bands are also discussed in a realistic metamaterials sample. These results show an alternative way toward molding the pseudospin flow in photonic systems.
Chávez, Alma; Maya, Catalina; Gibson, Richard; Jiménez, Blanca
2011-05-01
The Tula Valley receives untreated wastewater from Mexico City for agricultural irrigation, half of which infiltrates to aquifers from where drinking water is extracted. Samples of wastewater and infiltrated water from three areas of the valley were analyzed for microorganisms, organic micropollutants, and some basic parameters. Concentrations of microorganisms in the infiltrated water were generally very low but the incidence of fecal coliforms (present in 68% of samples), somatic bacteriophages (36%), Giardia spp. (14%), and helminth eggs (8%) suggested a health risk. Organic micropollutants, often present at high concentrations in the wastewater, were generally absent from the infiltrated water except carbamazepine which was in 55% of samples (up to 193 ng/L). There was no correlation between carbamazepine concentrations and the presence of microorganisms but highest concentrations of carbamazepine and boron coincided. A treatment such as nanofiltration would be necessary for the infiltrated water to be a safe potable supply. Copyright © 2011 Elsevier Ltd. All rights reserved.
Berenbrock, Charles
1987-01-01
Ground water is the sole source of water in Indian Wells Valley. Since 1966, annual ground-water pumpage has exceeded estimates of mean annual recharge, and continued and increased stresses on the aquifer system of the valley are expected. In 1981 the U.S. Geological Survey began a 10-year program to develop a data base that could be used in evaluating future water-management alternatives for the valley. This report tabulates existing water-level and water-quality data in order to provide a basis for the design of a ground-water monitoring network for Indian Wells Valley. Water-levels were measured in 131 wells during 1977-84. About 62 percent of the wells that have water-level measurements spanning at least 3 years during the period 1977-84 show a net water-level decline; the decline in 23 percent of the wells is greater than 5 feet. Water-quality samples from 85 wells were analyzed for major dissolved constituents. At selected wells water samples were also analyzed for nutrients and trace metals. Seventy-nine of the wells sampled contained water with concentrations of one or more dissolved constituents that equaled or exceeded U.S. Environmental Protection Agency primary or secondary maximum contaminant levels for drinking water. Dissolved-solids concentrations, which ranged from 190 to 67,000 milligrams per liter, equaled or exceeded 500 milligrams per liter (the Environmental Protection Agency secondary maximum contaminant level) in 85 percent of the sampled wells and 1,000 milligrams per liter in 59 percent. Water samples collected in 1984 from eight wells near the industrial-waste ponds of the China Lake Naval Weapons Center were analyzed for the presence of organic compounds designated 'priority pollutants' by the U.S. Environmental Protection Agency. Priority pollutants were detected in three wells. Trichloroethylene, methylene chloride, vinyl chloride, and chloroform were identified; concentrations were less than 10 micrograms per liter except for trichloroethylene and chloroform, at 94 and 12 micrograms per liter, respectively. Trichloroethylene in one sample and vinyl chloride in another exceeded Environmental Protection Agency proposed maximum contaminant levels.
A Spatial Analysis of Rift Valley Fever Virus Seropositivity in Domestic Ruminants in Tanzania
Sindato, Calvin; Pfeiffer, Dirk U.; Karimuribo, Esron D.; Mboera, Leonard E. G.; Rweyemamu, Mark M.; Paweska, Janusz T.
2015-01-01
Rift Valley fever (RVF) is an acute arthropod-borne viral zoonotic disease primarily occurring in Africa. Since RVF-like disease was reported in Tanzania in 1930, outbreaks of the disease have been reported mainly from the eastern ecosystem of the Great Rift Valley. This cross-sectional study was carried out to describe the variation in RVF virus (RVFV) seropositivity in domestic ruminants between selected villages in the eastern and western Rift Valley ecosystems in Tanzania, and identify potential risk factors. Three study villages were purposively selected from each of the two Rift Valley ecosystems. Serum samples from randomly selected domestic ruminants (n = 1,435) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM), using RVF enzyme-linked immunosorbent assay methods. Mixed effects logistic regression modelling was used to investigate the association between potential risk factors and RVFV seropositivity. The overall RVFV seroprevalence (n = 1,435) in domestic ruminants was 25.8% and speciesspecific seroprevalence was 29.7%, 27.7% and 22.0% in sheep (n = 148), cattle (n = 756) and goats (n = 531), respectively. The odds of seropositivity were significantly higher in animals sampled from the villages in the eastern than those in the western Rift Valley ecosystem (OR = 1.88, CI: 1.41, 2.51; p<0.001), in animals sampled from villages with soils of good than those with soils of poor water holding capacity (OR = 1.97; 95% CI: 1.58, 3.02; p< 0.001), and in animals which had been introduced than in animals born within the herd (OR = 5.08, CI: 2.74, 9.44; p< 0.001). Compared with animals aged 1–2 years, those aged 3 and 4–5 years had 3.40 (CI: 2.49, 4.64; p< 0.001) and 3.31 (CI: 2.27, 4.82, p< 0.001) times the odds of seropositivity. The findings confirm exposure to RVFV in all the study villages, but with a higher prevalence in the study villages from the eastern Rift Valley ecosystem. PMID:26162089
A Spatial Analysis of Rift Valley Fever Virus Seropositivity in Domestic Ruminants in Tanzania.
Sindato, Calvin; Pfeiffer, Dirk U; Karimuribo, Esron D; Mboera, Leonard E G; Rweyemamu, Mark M; Paweska, Janusz T
2015-01-01
Rift Valley fever (RVF) is an acute arthropod-borne viral zoonotic disease primarily occurring in Africa. Since RVF-like disease was reported in Tanzania in 1930, outbreaks of the disease have been reported mainly from the eastern ecosystem of the Great Rift Valley. This cross-sectional study was carried out to describe the variation in RVF virus (RVFV) seropositivity in domestic ruminants between selected villages in the eastern and western Rift Valley ecosystems in Tanzania, and identify potential risk factors. Three study villages were purposively selected from each of the two Rift Valley ecosystems. Serum samples from randomly selected domestic ruminants (n = 1,435) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM), using RVF enzyme-linked immunosorbent assay methods. Mixed effects logistic regression modelling was used to investigate the association between potential risk factors and RVFV seropositivity. The overall RVFV seroprevalence (n = 1,435) in domestic ruminants was 25.8% and species specific seroprevalence was 29.7%, 27.7% and 22.0% in sheep (n = 148), cattle (n = 756) and goats (n = 531), respectively. The odds of seropositivity were significantly higher in animals sampled from the villages in the eastern than those in the western Rift Valley ecosystem (OR = 1.88, CI: 1.41, 2.51; p<0.001), in animals sampled from villages with soils of good than those with soils of poor water holding capacity (OR = 1.97; 95% CI: 1.58, 3.02; p< 0.001), and in animals which had been introduced than in animals born within the herd (OR = 5.08, CI: 2.74, 9.44; p< 0.001). Compared with animals aged 1-2 years, those aged 3 and 4-5 years had 3.40 (CI: 2.49, 4.64; p< 0.001) and 3.31 (CI: 2.27, 4.82, p< 0.001) times the odds of seropositivity. The findings confirm exposure to RVFV in all the study villages, but with a higher prevalence in the study villages from the eastern Rift Valley ecosystem.
Alvarez, Nancy L.; Seiler, Ralph L.
2004-01-01
Discharge of treated municipal-sewage effluent to the Carson River in western Nevada and eastern California ceased by 1987 and resulted in a substantial decrease in phosphorus concentrations in the Carson River. Nonetheless, concentrations of total phosphorus and suspended sediment still commonly exceed beneficial-use criteria established for the Carson River by the Nevada Division of Environmental Protection. Potential sources of phosphorus in the study area include natural inputs from undisturbed soils, erosion of soils and streambanks, construction of low-head dams and their destruction during floods, manure production and grazing by cattle along streambanks, drainage from fields irrigated with streamwater and treated municipal-sewage effluent, ground-water seepage, and urban runoff including inputs from golf courses. In 2000, the U.S. Geological Survey (USGS), in cooperation with Carson Water Subconservancy District, began an investigation with the overall purpose of providing managers and regulators with information necessary to develop and implement total maximum daily loads for the Carson River. Two specific goals of the investigation were (1) to identify those reaches of the Carson River upstream from Lahontan Reservoir where the greatest increases in phosphorus and suspended-sediment concentrations and loading occur, and (2) to identify the most important sources of phosphorus within the reaches of the Carson River where the greatest increases in concentration and loading occur. Total-phosphorus concentrations in surface-water samples collected by USGS in the study area during water years 2001-02 ranged from <0.01 to 1.78 mg/L and dissolved-orthophosphate concentrations ranged from <0.01 to 1.81 mg/L as phosphorus. In streamflow entering Carson Valley from headwater areas in the East Fork Carson River, the majority of samples exceeding the total phosphorus water-quality standard of 0.1 mg/L occur during spring runoff (March, April, and May) when suspended-sediment concentrations are high. Downstream from Carson Valley, almost all samples exceed the water-quality standard, with the greatest concentrations observed during spring and summer months. Estimated annual total-phosphorus loads ranged from 1.33 tons at the West Fork Carson River at Woodfords to 43.41 tons at the Carson River near Carson City during water years 2001-02. Loads are greatest during spring runoff, followed by fall and winter, and least during the summer, which corresponds to the amount of streamflow in the Carson River. The estimated average annual phosphorus load entering Carson Valley was 21.9 tons; whereas, the estimated average annual phosphorus load leaving Carson Valley was 37.8 tons, for an annual gain in load across Carson Valley of 15.9 tons. Thus, about 58 percent of the total-phosphorus load leaving Carson Valley on an annual basis could be attributed to headwater reaches upstream from Carson Valley. During spring and summer (April 1-September 30) an average of 85 percent of the total-phosphorus load leaving Carson Valley could be attributed to headwater reaches. During fall and winter (October 1-March 31) only 17 percent of the phosphorus load leaving Carson Valley could be attributed to headwater reaches. The composition of the phosphorus changes during summer from particulate phosphorus entering Carson Valley to dissolved orthophosphate leaving Carson Valley. Particulate phosphorus entering Carson Valley could be settling out when water is applied to fields and be replaced by dissolved orthophosphate from other sources. Alternatively, the particulate phosphorus could be converted to dissolved orthophosphate as it travels across Carson Valley. Data collected during the study are not sufficient to distinguish between the two possibilities. Eagle Valley and Dayton-Churchill Valleys may act as sinks for phosphorus. On an annual basis, during water years 2001-02, about 90 percent of the phosphorus entering Eagle Valley left the
Union Listing via OCLC's Serials Control Subsystem.
ERIC Educational Resources Information Center
O'Malley, Terrence J.
1984-01-01
Describes library use of Conversion of Serials Project's (CONSER) online national machine-readable database for serials to create online union lists of serials via OCLC's Serial Control Subsystem. Problems in selection of appropriate, accurate, and authenticated records and prospects for the future are discussed. Twenty sources and sample records…
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.'
Payn, R.A.; Gooseff, M.N.; McGlynn, B.L.; Bencala, K.E.; Wondzell, S.M.
2009-01-01
Channel water balances of contiguous reaches along streams represent a poorly understood scale of stream-subsurface interaction. We measured reach water balances along a headwater stream in Montana, United States, during summer base flow recessions. Reach water balances were estimated from series of tracer tests in 13 consecutive reaches delineated evenly along a 2.6 km valley segment. For each reach, we estimated net change in discharge, gross hydrologic loss, and gross hydrologic gain from tracer dilution and mass recovery. Four series of tracer tests were performed during relatively high, intermediate, and low base flow conditions. The relative distribution of channel water along the stream was strongly related to a transition in valley structure, with a general increase in gross losses through the recession. During tracer tests at intermediate and low flows, there were frequent substantial losses of tracer mass (>10%) that could not be explained by net loss in flow over the reach, indicating that many of the study reaches were concurrently losing and gaining water. For example, one reach with little net change in discharge exchanged nearly 20% of upstream flow with gains and losses along the reach. These substantial bidirectional exchanges suggest that some channel interactions with subsurface flow paths were not measurable by net change in flow or transient storage of recovered tracer. Understanding bidirectional channel water balances in stream reaches along valleys is critical to an accurate assessment of stream solute fate and transport and to a full assessment of exchanges between the stream channel and surrounding subsurface. Copyright 2009 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Glas, R. L.; Lautz, L.; McKenzie, J. M.; Mark, B. G.; Baker, E. A.; Aubry-Wake, C.; Somers, L. D.; Wigmore, O.
2015-12-01
As tropical glaciers rapidly recede in response to climate change, the storage and discharge of groundwater will play an increasing role in regulating river baseflow, particularly during the dry season, when stream flow is currently sustained predominantly by glacial melt. Little is understood regarding the hydrogeologic processes controlling base flow characteristics of low-gradient proglacial valleys of the Cordillera Blanca in Northwestern Peru, which has the world's highest density of tropical glaciers. To better understand the processes of groundwater storage and discharge in proglacial meadows, we completed seismic refraction surveys in three representative valleys of the Cordillera Blanca range: the Quilcayhuanca, Yanamarey, and Pachacoto valleys. The locations of survey transects were chosen based on locations of previous sediment core sampling, GPR lines, and quantification of groundwater-surface water interaction derived from dye and temperature tracing experiments. The seismic surveys consisted of 48 vertical component geophones with 2.5 m spacing. Across the three representative valleys a total of 15 surveys were conducted, covering a distance of 1800 m in cross, down, and oblique-valley directions. Preliminary interpretation of the seismic refraction data indicates a maximum imaging depth of 16 m below land surface, and a transition from glacio-lacustrine sediments to buried saturated talus at a depth of 6 m in the Quilcayhuanca valley. The organic-rich glacio-lacustrine sediments in the Yanamarey valley have seismic velocities ranging from 300 to 800 m/s and are >16 m in thickness at mid- valley. Weathered metasedimentary bedrock in the Pachacoto valley was imaged at ~5 m below the valley surface, exhibiting a p-wave velocity of 3400 m/s. The knowledge of hydrogeologic structure derived from seismic refraction surveys will provide crucial boundary conditions for future groundwater models of the valleys of the Cordillera Blanca.
Geomorphic control of landscape carbon accumulation
Rosenbloom, N.A.; Harden, J.W.; Neff, J.C.; Schimel, D.S.
2006-01-01
We use the CREEP process-response model to simulate soil organic carbon accumulation in an undisturbed prairie site in Iowa. Our primary objectives are to identify spatial patterns of carbon accumulation, and explore the effect of erosion on basin-scale C accumulation. Our results point to two general findings. First, redistribution of soil carbon by erosion results in a net increase in basin-wide carbon storage relative to a noneroding environment. Landscape-average mean residence times are increased in an eroding landscape owing to the burial/preservation of otherwise labile C. Second, field observations taken along a slope transect may overlook significant intraslope variations in carbon accumulation. Spatial patterns of modeled deep C accumulation are complex. While surface carbon with its relatively short equilibration time is predictable from surface properties, deep carbon is strongly influenced by the landscape's geomorphic and climatic history, resulting in wide spatial variability. Convergence and divergence associated with upland swales and interfluves result in bimodal carbon distributions in upper and mid slopes; variability in carbon storage within modeled mid slopes was as high as simulated differences between erosional shoulders and depositional valley bottoms. The bimodality of mid-slope C variability in the model suggests that a three-dimensional sampling strategy is preferable over the traditional two-dimensional analog or "catena" approach. Copyright 2006 by the American Geophysical Union.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farhar, B. C.; Hunter, L. M.; Kirkland, T. M.
2010-06-01
This report is about the social acceptance of utility-scale concentrating solar power (CSP) plants in the San Luis Valley, approximately 200 miles southwest of Denver, Colorado. The research focused on social factors that may facilitate and impede the adoption and implementation of CSP. During the winter of 2008-2009, interviews were conducted with a purposive sample of 25 CSP-related stakeholders inside and outside the Valley. Interviews focused on the perceived advantages and disadvantages of siting a hypothetical 100-MW CSP facility in the Valley, the level of community support and opposition to CSP development, and related issues, such as transmission. State policymore » recommendations based on the findings include developing education programs for Valley residents, integrating Valley decision makers into an energy-water-land group, providing training for Valley decision makers, offering workforce training, evaluating models of taxation, and forming landholder energy associations. In addition, the SLV could become a laboratory for new approaches to CSP facility and transmission siting decision-making. The author recommends that outside stakeholders address community concerns and engage Valley residents in CSP decisions. Engaging the residents in CSP and transmission decisions, the author says, should take parallel significance with the investment in solar technology.« less
Social assistance and conjugal union dissolution in Canada: a dynamic analysis.
Lefebvre, P; Merrigan, P
1997-02-01
"Using Statistics Canada's General Social Survey on Family and Friends, carried out in 1990, we piece together the matrimonial and conjugal life history of a large sample of Canadian men and women. We then estimate duration models (Cox's proportional hazard models) describing the evolutionary laws of marriages and unions, which depend on various economic or socio-demographic explanatory variables. The empirical modelling focuses primarily on estimating the impact of couples' earned incomes and of provincial welfare programs on the dissolution rate of first marriages and unions....We...find that welfare benefits do not have an impact on the hazard of union dissolution and that earned incomes have a positive effect on conjugal stability." (EXCERPT)
Hydrology of Northern Utah Valley, Utah County, Utah, 1975-2005
Cederberg, Jay R.; Gardner, Philip M.; Thiros, Susan A.
2009-01-01
The ground-water resources of northern Utah Valley, Utah, were assessed during 2003-05 to describe and quantify components of the hydrologic system, determine a hydrologic budget for the basin-fill aquifer, and evaluate changes to the system relative to previous studies. Northern Utah Valley is a horst and graben structure with ground water occurring in both the mountain-block uplands surrounding the valley and in the unconsolidated basin-fill sediments. The principal aquifer in northern Utah Valley occurs in the unconsolidated basin-fill deposits where a deeper unconfined aquifer occurs near the mountain front and laterally grades into multiple confined aquifers near the center of the valley. Sources of water to the basin-fill aquifers occur predominantly as either infiltration of streamflow at or near the interface of the mountain front and valley or as subsurface inflow from the adjacent mountain blocks. Sources of water to the basin-fill aquifers were estimated to average 153,000 (+/- 31,500) acre-feet annually during 1975-2004 with subsurface inflow and infiltration of streamflow being the predominant sources. Discharge from the basin-fill aquifers occurs in the valley lowlands as flow to waterways, drains, ditches, springs, as diffuse seepage, and as discharge from flowing and pumping wells. Ground-water discharge from the basin-fill aquifers during 1975-2004 was estimated to average 166,700 (+/- 25,900) acre-feet/year where discharge to wells for consumptive use and discharge to waterways, drains, ditches, and springs were the principal sources. Measured water levels in wells in northern Utah Valley declined an average of 22 feet from 1981 to 2004. Water-level declines are consistent with a severe regional drought beginning in 1999 and continuing through 2004. Water samples were collected from 36 wells and springs throughout the study area along expected flowpaths. Water samples collected from 34 wells were analyzed for dissolved major ions, nutrients, and stable isotopes of hydrogen and oxygen. Water samples from all 36 wells were analyzed for dissolved-gas concentration including noble gases and tritium/helium-3. Within the basin fill, dissolved-solids concentration generally increases with distance along flowpaths from recharge areas, and shallower flowpaths tend to have higher concentrations than deeper flowpaths. Nitrate concentrations generally are at or below natural background levels. Dissolved-gas recharge temperature data support the conceptual model of the basin-fill aquifers and highlight complexities of recharge patterns in different parts of the valley. Dissolved-gas data indicate that the highest elevation recharge sources for the basin-fill aquifer are subsurface inflow derived from recharge in the adjacent mountain block between the mouths of American Fork and Provo Canyons. Apparent ground-water ages in the basin-fill aquifer, as calculated using tritium/helium-3 data, range from 2 to more than 50 years. The youngest waters in the valley occur near the mountain fronts with apparent ages generally increasing near the valley lowlands and discharge area around Utah Lake. Flowpaths are controlled by aquifer properties and the location of the predominant recharge sources, including subsurface inflow and recharge along the mountain front. Subsurface inflow is distributed over a larger area across the interface of the subsurface mountain block and basin-fill deposits. Subsurface inflow occurs at a depth deeper than that at which mountain-front recharge occurs. Recharge along the mountain front is often localized and focused over areas where streams and creeks enter the valley, and recharge is enhanced by the associated irrigation canals.
Paleo-Ice flow and overdeepenings in an Alpine setting: Examples from the Tyrolian Alps (Austria)
NASA Astrophysics Data System (ADS)
Reitner, J. M.; Gruber, W.
2009-04-01
Overdeepened valleys and basins are the most interesting features of former glacial action in Alpine areas. Understanding the formation of such phenomena are not only a scientific task but also an important challenge for a society increasingly exploiting sustainable natural resources even in remote areas. The feasibility of hydrogeological or geothermal projects, for instance, depends on the bedrock depth and the sedimentary infill of such valleys. Generally, overdeepened valleys are formed in areas where the ice discharge was high, such as near the equilibrium line, at valley junctions, or at narrowings of the valley profile. The long known overdeepened tongue basins in the Eastern Alps are regarded as typical examples of the impact of high ice flow velocities combined with increased debris load and running water under hydrostatic pressure around the former (LGM, and older glaciations) equilibrium lines (e.g. van Husen, 2000). However, within a highly dissected mountain topography like that of the Eastern Alps the existence of overdeepened valleys-parts supposedly also reflects changes in ice flow direction and velocity during glacial history within one glacial event (like the LGM) as well as during the Pleistocene. For example, ice flow in the phase of ice build-up at the beginning of major glaciations is controlled by the topography and trend of the valleys whereas during the climax of the big glaciations a mountain ice cap exists with a continuous discharge across water divides. Thus, the onsets of ice transfluences as well as the valley orientation in relation to the changing ice flow direction are regarded as major conditions for overdeepenings in an inneralpine setting. Such a complex and changing pattern of ice flow will be shown by the example of the Inn valley and its tributary valleys in the S and E (valley of the Wildschönauer Ache and of the Brixentaler Ache). Based on extensive geological mapping and lithostratigraphy in combination with geophysical surveys, a model of the LGM ice flow, its variation and its effect on glacial erosion is developed. On the one hand the effect of topography on ice dynamics in terms of promoting ice build-up as well as restricting erosion is evident. For the tributary valleys, on the other hand, the biggest amount of glacial erosion most probably occurred during the phase of ice build-up. However, seismic data, especially seismic stratigraphy (Reitner et al., 2007), shows the limitations of paleo-glaciological models derived from the youngest sequence, in this case the LGM sequence, for explaining sedimentary remnants of older glaciations. According to our example shifts of, and changes in, the amount of glacial erosion in tributary valleys may best be explained by changes in the onset of ice transfluences during ice build-up. Hence, a step-by-step lowering of passes and cols (water divides) during pleniglacial conditions had a profound impact on the ice dynamics of the following glaciation and, thus, on the occurrence of overdeepenings. Our model for a dynamic evolution of morphology presents an inverse relationship between the shaping of the surface and the subsurface and may only hold for a restricted area. However, this non-static view on glacier constellation and its change through time can explain the occurrence of unexpected overdeepenings or changes in erratic clast content elsewhere in dissected, formerly glaciated, Alpine landscapes. References: Husen, D. van, 2000. Geological Processes during the Quaternary.- Mitteilungen der Österreichischen Geologischen Gesellschaft, 92 (1999), 135-156, Wien. Reitner, J.M., Gruber, W., Römer, A., Bieber, G., Schmid, C., 2007. Complex Pleistocene stratigraphy and structure within an inneralpine setting: The basin of Hopfgarten (Northern Tyrol/Austria).- Geophysical Research Abstracts, Vol. 9, 09369, 2007, SRef-ID: 1607-7962/gra/EGU2007-A-09369, European Geosciences Union.
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.
Patterns of Rift Valley fever activity in Zambia.
Davies, F. G.; Kilelu, E.; Linthicum, K. J.; Pegram, R. G.
1992-01-01
An hypothesis that there was an annual emergence of Rift Valley fever virus in Zambia, during or after the seasonal rains, was examined with the aid of sentinel cattle. Serum samples taken during 1974 and 1978 showed evidence of epizootic Rift Valley fever in Zambia, with more than 80% positive. A sentinel herd exposed from 1982 to 1986 showed that some Rift Valley fever occurred each year. This was usually at a low level, with 3-8% of the susceptible cattle seroconverting. In 1985-6 more than 20% of the animals seroconverted, and this greater activity was associated with vegetational changes--which could be detected by remote-sensing satellite imagery--which have also been associated with greater virus activity in Kenya. PMID:1547835
Albert, Midori A; Maier, Christopher A
2013-11-01
Epiphyseal union stages for cervical vertebral centra (ring epiphyses) were documented for 55 individuals (females and males, ages 14-27 years) from the Terry Collection, using the Albert and Maples method 1, to examine both its relationship to age at death and to thoracic data collected from the same individuals using the same method. Results showed a moderate correlation between cervical ring union and age (r = 0.63, p = 0.000), and a fairly low correlation between cervical and thoracic ring union (r = 0.41, p = 0.002). Paired samples t-tests yielded a statistically significant difference between cervical and thoracic union mean values (p = 0.01). Union progressed earlier in cervical vertebrae and in females. Results indicated fairly substantial variation in both sexes. Findings may serve as a basic guideline for estimating a general age range at death for unknown skeletal remains and to corroborate findings from other skeletal age indicators. © 2013 American Academy of Forensic Sciences.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keighin, C.W.; Flores, R.M.; Ochs, A.
In southwestern North Dakota, minable lignite beds in the Paleocene Fort Union Formation include the Harmon and Hansen beds in the Bowman-Gascoyne area. Data from more than 700 drill holes penetrating these beds was used to construct stratigraphic cross sections. The Harmon and Hansen beds are the thickest and most laterally persistent lignites found under < 150 ft of overburden. The Harmon coal bed is as much as 34 ft thick, and is often split by claystone interbeds of variable thickness. The Hansen coal bed typically occurs 10--100 ft below the Harmon coal bed; it rarely attains a thickness ofmore » 15 ft, and averages 4 ft in thickness.« less
Relation of Chlorofluorocarbon Ground-Water Age Dates to Water Quality in Aquifers of West Virginia
,; Kurt, J.; Kozar, Mark D.
2007-01-01
The average apparent age of ground water in fractured-bedrock aquifers in West Virginia was determined using chlorofluorocarbon (CFC) dating methods. Since the introduction of CFC gases as refrigerants in the late 1930s, atmospheric concentrations have increased until production ceased in the mid-1990s. CFC dating methods are based on production records that date to the early 1940s, and the preservation of atmospheric CFC concentrations in ground water at the time of recharge. As part of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) and Ambient Ground-Water Monitoring Network (AGN) programs in West Virginia from 1997 to 2005, 80 samples from the Appalachian Plateaus Physiographic Province, 27 samples from the Valley and Ridge Physiographic Province, and 5 samples from the Ohio River alluvial aquifers were collected to estimate ground-water ages in aquifers of West Virginia. Apparent CFC ages of water samples from West Virginia aquifers ranged from 5.8 to 56 years. In the Appalachian Plateaus, topographically driven ground-water flow is evident from apparent ages of water samples from hilltop, hillside, and valley settings (median apparent ages of 12, 14, and 25 years, respectively). Topographic setting was the only factor that was found to be related to apparent ground-water age in the Plateaus at the scale of this study. Similar relations were not found in Valley and Ridge aquifers, indicating that other factors such as bedding or geologic structure may serve larger roles in controlling ground-water flow in that physiographic province. Degradation of CFCs was common in samples collected from methanogenic/anoxic aquifers in the Appalachian Plateaus and suboxic to anoxic aquifers in the Valley and Ridge. CFC contamination was most common in Ohio River alluvial aquifers and carbonate units of the Valley and Ridge, indicating that these highly transmissive surficial aquifers are the most vulnerable to water-quality degradation and may contain wastewater from domestic or industrial sources with CFC concentrations greater than modern atmospheric levels. However, based on a lack of detections of the volatile organic compounds analyzed for in most of the water samples collected for this and similar USGS investigations, ground-water resources of West Virginia used for public and private consumption do not appear to be routinely affected by anthropogenic activities despite their young apparent age.
McPherson, Ann K.; Abrahamsen, Thomas A.; Journey, Celeste A.
2002-01-01
The U.S. Geological Survey conducted a 16-month investigation of water quality, aquatic-community structure, bed sediment, and fish tissue in Village and Valley Creeks, two urban streams that drain areas of highly intensive residential, commercial, and industrial land use in Birmingham, Alabama. Water-quality data were collected between February 2000 and March 2001 at four sites on Village Creek, three sites on Valley Creek, and at two reference sites near Birmingham?Fivemile Creek and Little Cahaba River, both of which drain less-urbanized areas. Stream samples were analyzed for major ions, nutrients, fecal bacteria, trace and major elements, pesticides, and selected organic constituents. Bed-sediment and fish-tissue samples were analyzed for trace and major elements, pesticides, polychlorinated biphenyls, and additional organic compounds. Aquatic-community structure was evaluated by conducting one survey of the fish community and in-stream habitat and two surveys of the benthic-invertebrate community. Bed-sediment and fish-tissue samples, benthic-invertebrates, and habitat data were collected between June 2000 and October 2000 at six of the nine water-quality sites; fish communities were evaluated in April and May 2001 at the six sites where habitat and benthic-invertebrate data were collected. The occurrence and distribution of chemical constituents in the water column and bed sediment provided an initial assessment of water quality in the streams. The structure of the aquatic communities, the physical condition of the fish, and the chemical analyses of fish tissue provided an indication of the cumulative effects of water quality on the aquatic biota. Water chemistry was similar at all sites, characterized by strong calcium-bicarbonate component and magnesium components. Median concentrations of total nitrogen and total phosphorus were highest at the headwaters of Valley Creek and lowest at the reference site on Fivemile Creek. In Village Creek, median concentrations of nitrite and ammonia increased in a downstream direction. In Valley Creek, median concentrations of nitrate, nitrite, ammonia, organic nitrogen, suspended phosphorus, and orthophosphate decreased in a downstream direction. Median concentrations of Escherichia coli and fecal coliform bacteria were highest at the most upstream site of Valley Creek and lowest at the reference site on Fivemile Creek. Concentrations of enterococci exceeded the U.S. Environmental Protection Agency criterion in 80 percent of the samples; concentrations of Escherichia coli exceeded the criterion in 56 percent of the samples. Concentrations of bacteria at the downstream sites on Village and Valley Creeks were elevated during high flow rather than low flow, indicating the presence of nonpoint sources. Surface-water samples were analyzed for chemical compounds that are commonly found in wastewater and urban runoff. The median number of wastewater indicators was highest at the most upstream site on Valley Creek and lowest at the reference site on Fivemile Creek. Concentrations of total recoverable cadmium, copper, lead, and zinc in surface water exceeded acute and chronic aquatic life criteria in up to 24 percent of the samples that were analyzed for trace and major elements. High concentrations of trace and major elements in the water column were detected most frequently during high flow, indicating the presence of nonpoint sources. Of the 24 pesticides detected in surface water, 17 were herbicides and 7 were insecticides. Atrazine, simazine, and prometon were the most commonly detected herbicides; diazinon, chlorpyrifos, and carbaryl were the most commonly detected insecticides. Concentrations of atrazine, carbaryl, chlorpyrifos, diazinon, and malathion periodically exceeded criteria for the protection of aquatic life. Trace-element priority pollutants, pesticides, and other organic compounds were detected in higher concentrations in bed sediment at the Village and Valley Creek sites t
Hydrology of stock-water development on the public domain of western Utah
Snyder, Charles T.
1963-01-01
A geologic and hydrologic reconnaissance was made on the public domain of western Utah to appraise the water resources of the area and to provide a basis for locating and developing sources of stock water. The study area includes the Bonneville, Pahvant, and Virgin Grazing Districts, in parts of Tooele, Utah, Juab, Millard, Beaver, Iron, and Washington Counties, Utah.Western Utah is in the Great Basin section of the Basin and Range physiographic province and is typified by northward-trending parallel mountain ranges, and basins of interior drainage. Precipitation ranges from 5 to 9 inches annually in most of the valleys but in some places it is as much as 15 or 16 inches and probably is considerably greater in the mountains.The valleys of western Utah have been classified in the report according to their hydrologic and topographic characteristics. The Great Salt Lake valley and the Sevier Lake valley are closed or terminal valleys having no outlet for the discharge of water except by evaporation. Such valleys are topographically closed and hydrologically undrained. Valleys tributary to these terminal valleys are topographically open valleys from which water is discharged by gravity flow to the terminal valley. Quality of ground water in the valleys of western Utah depends upon the valley type and place where the water is sampled with respect to the body of ground water in the valley fill. Quality of the water in the drained parts of the valleys is usually good whereas water in the undrained parts of the valleys may be heavily charged with dissolved mineral contaminants. Limits of tolerance for use of salt-contaminated water are cited.The adequacy of distribution of water supplies in western Utah was determined by application of the service area concept to the existing supplies. Stock-water supplies are obtained from wells, springs, and reservoirs. Most of the wells are in the valleys where water is obtained from valley fill; the depth to water ranges from a few tens of feet to several hundred feet. Ground water generally cannot be obtained in the mountains because the rocks either lack permeability or are drained.Data collected in 13 valleys, each valley forming a ground-water unit, are listed in the tables and are used to evaluate the prospects for obtaining additional water supplies.
Domagalski, Joseph L.
1997-01-01
A nested surface water monitoring network was designed and tested to measure variability in pesticide concentrations in the San Joaquin River and selected tributaries during the irrigation season. The network design an d sampling frequency necessary for determining the variability and distribution in pesticide concentrations were tested in a prototype study. The San Joaquin River Basin, California, was sampled from April to August 1992, a period during the irrigation season where there was no rainfall. Orestimba Creek, which drains a part of the western San Joaquin Valley, was sampled three times per week for 6 weeks, followed by a once per week sampling for 6 weeks, and the three times per week sampling for 6 weeks. A site on the San Joaquin River near the mouth of the basin, and an irrigation drain of the eastern San Joaquin Valley, were sampled weekly during the entire sampling period. Pesticides were most often detected in samples collected from Orestimba Creek. This suggests that the western valley was the principal source of pesticides to the San Joaquin River during the irrigation season. Irrigation drainage water was the source of pesticides to Orestimba Creek. Pesticide concentrations of Orestimba Creek showed greater temporal variability when sampled three times per week than when sampled once a week, due to variations in field management and irrigation. The implication for the San Joaquin River basin (an irrigation-dominated agricultural setting) is that frequent sampling of tributary sites is necessary to describe the variability in pesticides transported to the San Joaquin River.
Geohydrology of the Souris River Valley in the vicinity of Minot, North Dakota
Pettyjohn, Wayne A.
1967-01-01
The Minot area is in the north-central part of North Dakota and includes part of the Souris River valley. The region is covered by glacial drift of late Wisconsin age except in small areas where the Fort Union Formation of Tertiary age crops out. Thickness of the drift is controlled by the topography of the bedrock. In places the drift is more than 450 feet thick, but it averages about 100 feet thick.Water from the Fort Union Formation is soft and is of sodium bicarbonate type that is undesirable for many uses. Wells in the formation produce only a few gallons per minute.Six glacial aquifers were studied in the report area, but detailed work was limited to the Minot aquifer. The Sundre buried-channel and the lower Souris aquifers contain large quantities of bard water of good chemical quality, but little is known of their hydraulic characteristics owing to lack of development. The North Hill and South Hill aquifers generally provide small quantities of hard water that may be high in iron and sodium. The northwest buried-channel aquifer has a high content of iron and chloride. Locally as much as 1,000 gallons per minute may be pumped from it.The Minot aquifer is a thick deposit of sand and gravel confined to the Souris River valley. The water level has declined more than 70 feet since the first municipal well began pumping in 1916. In .some places the water level in the aquifer declined more than 20 feet during 1961-1963. The rapid decline in water level indicates that a serious water shortage may arise in the near future unless counter measures are taken to prevent it.The Minot aquifer is under both artesian and water-table conditions. In places the transmissibility exceeds 250,000 gallons per day per foot. In 1963, 13 municipal wells pump'ed an average of nearly 4 million gallons per day from the aquifer. Some wells produce as much as 1,000 gallons per minute. The Minot aquifer receives most of its recharge from the buried glaciofiuvial deposits and from the Souris River. Natural recharge probably average about 3 million gallons per day. About 56,000 acre-feet of water available to wells was in storage in 1963.Artificial recharge could be used to counteract the rapid decline in water levels. Several feasible artificial recharge sites are in the western part of Minot, where highly permeable sand and gravel crop out.
Baudin, Maria; Jumaa, Ammar M; Jomma, Huda J E; Karsany, Mubarak S; Bucht, Göran; Näslund, Jonas; Ahlm, Clas; Evander, Magnus; Mohamed, Nahla
2016-11-01
Rift Valley fever virus is an emerging mosquito-borne virus that causes infections in animals and human beings in Africa and the Arabian Peninsula. Outbreaks of Rift Valley fever lead to mass abortions in livestock, but such abortions have not been identified in human beings. Our aim was to investigate the cause of miscarriages in febrile pregnant women in an area endemic for Rift Valley fever. Pregnant women with fever of unknown origin who attended the governmental hospital of Port Sudan, Sudan, between June 30, 2011, and Nov 17, 2012, were sampled at admission and included in this cross-sectional study. Medical records were retrieved and haematological tests were done on patient samples. Presence of viral RNA as well as antibodies against a variety of viruses were analysed. Any association of viral infections, symptoms, and laboratory parameters to pregnancy outcome was investigated using Pearson's χ 2 test. Of 130 pregnant women with febrile disease, 28 were infected with Rift Valley fever virus and 31 with chikungunya virus, with typical clinical and laboratory findings for the infection in question. 15 (54%) of 28 women with an acute Rift Valley fever virus infection had miscarriages compared with 12 (12%) of 102 women negative for Rift Valley fever virus (p<0·0001). In a multiple logistic regression analysis, adjusting for age, haemorrhagic disease, and chikungunya virus infection, an acute Rift Valley fever virus infection was an independent predictor of having a miscarriage (odds ratio 7·4, 95% CI 2·7-20·1; p<0·0001). This study is the first to show an association between infection with Rift Valley fever virus and miscarriage in pregnant women. Further studies are warranted to investigate the possible mechanisms. Our findings have implications for implementation of preventive measures, and evidence-based information to the public in endemic countries should be strongly recommended during Rift Valley fever outbreaks. Schlumberger Faculty for the Future, CRDF Global (31141), the Swedish International Development Cooperation Agency, the County Council of Västerbotten, and the Faculty of Medicine, Umeå University. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.
75 FR 80364 - Sample Income Data To Meet the Low-Income Definition
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-22
..., that member data drawn from loan applications or member surveys be used to show a majority of the... particular credit union are compared with like categories of statistical data on income from the Census... of statistical data. For example, if a credit union provides individual income information for...
ERIC Educational Resources Information Center
Liefbroer, Aart C.; Gierveld, Jenny De Jong
1993-01-01
Found that plans of representative sample of young adults in Netherlands concerning choice between cohabitation and marriage were predicted by rational evaluation of difference between marriage and cohabitation and by perceived opinions of significant others. Effects of family background and social status variables on union formation intentions…
Using Marital Attitudes in Late Adolescence to Predict Later Union Transitions
ERIC Educational Resources Information Center
Willoughby, Brian J.
2014-01-01
Using a sample of 982 late adolescents and tracking them throughout young adulthood, this study investigated whether marital attitudes held during the last year of high school were predictive of union transitions to both cohabitation and marriage during young adulthood. Results using both logistic regression and discrete event history models found…
Temperature profiles from Salt Valley, Utah
NASA Astrophysics Data System (ADS)
Sass, J. H.; Lachenbruch, A. H.; Smith, E. P.
Temperature profiles were obtained in the nine drilled wells as part of a thermal study of the Salt Valley anticline, Paradox Basin, Utha. Thermal conductivities were also measured on 10 samples judged to be representative of the rocks encountered in the deepest hole. The temperature profiles and thermal conductivities are presented, together with preliminary interpretive remarks and suggestions for additional work.
Lithium in rocks from the Lincoln, Helena, and Townsend areas, Montana
Brenner-Tourtelot, Elizabeth F.; Meier, Allen L.; Curtis, Craig A.
1978-01-01
In anticipation of increased demand for lithium for energy-related uses, the U.S. Geological Survey has been appraising the lithium resources of the United States and investigating occurrences of lithium. Analyses of samples of chiefly lacustrine rocks of Oligocene age collected by M. R. Mudge near Lincoln, Mont. showed as much as 1,500 ppm lithium. Since then we have sampled the area in greater detail, and have sampled rocks of similar ages in the Helena and Townsend valleys. The lithium-rich beds crop out in a band about 1.3 km long by 0.3 km wide near the head of Beaver Creek, about 14 km northwest of Lincoln, Mont. These beds consist of laminated marlstone, oil shale, carbonaceous shale, limestone, conglomerate, and tuff. Some parts of this sequence average almost 0.1 percent lithium. The lithium-bearing rocks are too low in grade and volume to be economic. Samples of sedimentary rocks of Oligocene age from the Helena and Townsend valleys in the vicinity of Helena, Mont. were generally low in lithium (3-40 ppm). However, samples of rhyolites from the western side of the Helena valley and from the Lava Mountain area were slightly above average in lithium content (6-200 ppm).
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.
Prevalence of anxiety, depression and post-traumatic stress disorder in the Kashmir Valley
Lenglet, Annick; Ariti, Cono; Shah, Showkat; Shah, Helal; Ara, Shabnum; Viney, Kerri; Janes, Simon; Pintaldi, Giovanni
2017-01-01
Background Following the partition of India in 1947, the Kashmir Valley has been subject to continual political insecurity and ongoing conflict, the region remains highly militarised. We conducted a representative cross-sectional population-based survey of adults to estimate the prevalence and predictors of anxiety, depression and post-traumatic stress disorder (PTSD) in the 10 districts of the Kashmir Valley. Methods Between October and December 2015, we interviewed 5519 out of 5600 invited participants, ≥18 years of age, randomly sampled using a probability proportional to size cluster sampling design. We estimated the prevalence of a probable psychological disorder using the Hopkins Symptom Checklist (HSCL-25) and the Harvard Trauma Questionnaire (HTQ-16). Both screening instruments had been culturally adapted and translated. Data were weighted to account for the sampling design and multivariate logistic regression analysis was conducted to identify risk factors for developing symptoms of psychological distress. Findings The estimated prevalence of mental distress in adults in the Kashmir Valley was 45% (95% CI 42.6 to 47.0). We identified 41% (95% CI 39.2 to 43.4) of adults with probable depression, 26% (95% CI 23.8 to 27.5) with probable anxiety and 19% (95% CI 17.5 to 21.2) with probable PTSD. The three disorders were associated with the following characteristics: being female, over 55 years of age, having had no formal education, living in a rural area and being widowed/divorced or separated. A dose–response association was found between the number of traumatic events experienced or witnessed and all three mental disorders. Interpretation The implementation of mental health awareness programmes, interventions aimed at high risk groups and addressing trauma-related symptoms from all causes are needed in the Kashmir Valley. PMID:29082026
Sanger, Elizabeth A.; Ponce, David A.
2003-01-01
In June, 2002, the U.S. Geological Survey (USGS) established 143 new gravity stations and 12 new rock samples in the Dry Valley area, 30 miles north of Reno, Nevada, on the California - Nevada border (see fig. 1). This study reports on gravity, magnetic, and physical property data intended for use in modeling the geometry and depth of Dry Valley for groundwater analysis. It is part of a larger study that aims to characterize the hydrologic framework of several basins in Washoe County. Dry Valley is located south of the Fort Sage Mountains and south-east of Long Valley, on USGS 7.5’ quadrangles Constantia and Seven Lakes (fig. 2). The Cretaceous granitic rocks and Tertiary volcanic rocks that bound the sediment filled basin (fig. 3) may be especially important to future modeling because of their impact on groundwater flow. The granitic and volcanic rocks of Dry Valley exhibit densities and magnetic susceptibilities higher than the overlaying sediments, and create a distinguishable pattern of gravity and magnetic anomalies that reflect these properties.
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
Serological status of Canadian cattle for brucellosis, anaplasmosis, and bluetongue in 2007-2008.
Paré, Julie; Geale, Dorothy W; Koller-Jones, Maria; Hooper-McGrevy, Kathleen; Golsteyn-Thomas, Elizabeth J; Power, Christine A
2012-09-01
A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed.
Serological surveillance studies confirm the Rift Valley fever virus free status in South Korea.
Kim, Hyun Joo; Park, Jee-Yong; Jeoung, Hye-Young; Yeh, Jung-Yong; Cho, Yun-Sang; Choi, Jeong-Soo; Lee, Ji-Youn; Cho, In-Soo; Yoo, Han-Sang
2015-10-01
Rift Valley fever is a mosquito-borne zoonotic disease of domestic ruminants. This disease causes abortions in pregnant animals, and it has a high mortality rate in newborn animals. Recently, a Rift Valley fever virus (RVFV) outbreak in the Arabian Peninsula increased its potential spread to new regions worldwide. In non-endemic or disease-free countries, early detection and surveillance are important for preventing the introduction of RVFV. In this study, a serological surveillance was conducted to detect antibodies against RVFV. A total of 2382 serum samples from goats and cattle were randomly collected from nine areas in South Korea from 2011 to 2013. These samples were tested for antibodies against RVFV, using commercial ELISA kits. None of the goats and cattle were positive for antibodies against RVFV. This finding suggests that this disease is not present in South Korea, and furthermore presents the evidence of the RVFV-free status of this country.
Valley fill in the Roswell-Artesia area, New Mexico
Lyford, Forest P.
1973-01-01
Drill samples from 225 water and oil wells in an area 70 miles long and 20 miles wide in the Roswell-Artesia area, southeastern New Mexico were examined. A thickness map and a saturated thickness map of the valley-fill sediments were constructed. Maximum depth of valley fill is about 300 feet in large closed depressions near Roswell, Hagerman, and Artesia. The depressions were formed by the solution of carbonates and evaporites that underlie the fill. Maximum saturated thickness is about 250 feet in depressions near Hagerman and Artesia and about 300 feet in a depression near Roswell.
Bhattachan, Balkrishna; Sherchand, Jeevan Bahadhur; Tandukar, Sarmila; Dhoubhadel, Bhim Gopal; Gauchan, Leesa; Rai, Ganesh
2017-09-07
The aim of this study is to determine the prevalence of Cyclospora cayetanensis and Cryptosporidium parvum infections among people living a slum in Kathmandu valley, Nepal. Ten different parasites were detected in the stool samples; the prevalence of any parasite was in 27.1% (71/262). The prevalence of C. cayetanensis and C. parvum were 14.1% (10/71) and 5.6% (4/71), respectively. This study showed high prevalence of intestinal parasitic infections along with the coccidian parasites in the slum area of Kathmandu Valley.
Chelsea Lancelle
2013-09-11
In September 2013, an experiment using Distributed Acoustic Sensing (DAS) was conducted at Garner Valley, a test site of the University of California Santa Barbara (Lancelle et al., 2014). This submission includes all DAS data recorded during the experiment. The sampling rate for all files is 1000 samples per second. Any files with the same filename but ending in _01, _02, etc. represent sequential files from the same test. Locations of the sources are plotted on the basemap in GDR submission 481, titled: "PoroTomo Subtask 3.2 Sample data from a Distributed Acoustic Sensing experiment at Garner Valley, California (PoroTomo Subtask 3.2)." Lancelle, C., N. Lord, H. Wang, D. Fratta, R. Nigbor, A. Chalari, R. Karaulanov, J. Baldwin, and E. Castongia (2014), Directivity and Sensitivity of Fiber-Optic Cable Measuring Ground Motion using a Distributed Acoustic Sensing Array (abstract # NS31C-3935), AGU Fall Meeting. https://agu.confex.com/agu/fm1/meetingapp.cgi#Paper/19828 The e-poster is available at: https://agu.confex.com/data/handout/agu/fm14/Paper_19828_handout_696_0.pdf
White, D.H.; Mitchell, C.A.; Kennedy, H.R.; Krynitsky, A.J.; Ribick, M.A.
1983-01-01
A potential organochlorine pesticide problem was identified near Mission, Texas, by the National Park Monitoring Program. Fish samples from this site have consistently contained elevated levels of DDE since 1968. Surveys were made in 1976, 1978, and 1979 to determine the extent of organochlorine pesticide contamination in fishes and birds of the area. Freshwater fishes of Arroyo Colorado, a major waterway traversing the lower Rio Grande Valley, were highly contaminated with DDE and toxaphene residues compared to samples from other areas in the Valley; both DDE and toxaphene ranged up to 31.5 ppm wet wt in whole-fish composite samples. Median DDE residues in fish-eating bird carcasses from this area ranged up to 34 ppm wet wt, and 81 ppm in individual specimens. The levels of contaminants detected in fishes and birds were within, or above, the range producing adverse effects in certain species. The major sources of contamination to the Arroyo Colorado system likely stem from past and present use of persistent pesticides on surrounding croplands, and possibly from an abandoned pesticide plant at Mission, Texas.
NASA Astrophysics Data System (ADS)
Sydoff, Marie; Stenström, Kristina
2010-04-01
The Department of Physics at Lund University is participating in a European Union project called EUMAPP (European Union Microdose AMS Partnership Programme), in which sample preparation and accelerator mass spectrometry (AMS) measurements of biological samples from microdosing studies have been made. This paper describes a simplified method of converting biological samples to solid graphite for 14C analysis with AMS. The method is based on online combustion of the samples, and reduction of CO 2 in septa-sealed vials. The septa-sealed vials and disposable materials are used to eliminate sample cross-contamination. Measurements of ANU and Ox I standards show deviations of 2% and 3%, respectively, relative to reference values. This level of accuracy is sufficient for biological samples from microdosing studies. Since the method has very few handling steps from sample to graphite, the risk of failure during the sample preparation process is minimized, making the method easy to use in routine preparation of samples.
USDA-ARS?s Scientific Manuscript database
In this paper, we describe the importance of hyporheic dynamics within Andersen Creek and Von Guerard Stream, Taylor Valley, Antarctica, from the 2010-11 melt season using natural tracers. Water collection started at flow onset and continued, with weekly hyporheic zone sampling. The water d18O and d...
Participation in Summer School and High School Graduation in the Sun Valley High School District
ERIC Educational Resources Information Center
Trujillo, Gabriel
2012-01-01
This study examines the effectiveness of a summer school credit recovery program in the Sun Valley High School District. Using logistic regression I assess the relationship between race, gender, course failure, school of origin and summer school participation for a sample of students that failed one or more classes in their first year of high…
William T. Borrie; James A. Harding
2002-01-01
A four-stage model of decisionmaking was investigated in the context of low-impact practices among rock climbers in the Bitterroot Valley of Montana. Previous research has suggested that knowing what to do to minimize environmental and social impacts may not be the only factor limiting compliance with recommended visitor behaviors. Results from a sample of climbers at...
ERIC Educational Resources Information Center
MILLERD, FRANK W.; VERNER, COOLIE
THIS STUDY ANALYZED THE GENERAL BEHAVIOR OF ORCHARDISTS IN THE OKANAGAN VALLEY, BRITISH COLUMBIA, AND THE FACTORS RELATED TO ADOPTION OF INNOVATIONS IN THIS SETTING. FIVE PERCENT SAMPLES WERE DRAWN FROM 19 DISTRICTS CONSISTING OF 2,721 ORCHARDS, AND DATA WERE GATHERED BY RESIDENT AGRICULTURISTS. THE DATA WERE ANALYZED BY STAGE IN THE ADOPTION…
Potential impact of air quality restrictions on logging residue burning
Owen P. Cramer; James N. Westwood
1970-01-01
The number of potential burning days and the potential burn acreage under smoke control restrictions were estimated for hypothetical forest areas on both sides of a pollution prone area, the Willamette Valley in western Oregon. On the basis of a sample of 2 dry years, the greatest impact on burning operations applied to low elevation forests west of the Valley. The...
Food Label Use and Food Label Skills among Immigrants from the Former Soviet Union
ERIC Educational Resources Information Center
Lubman, Nadia; Doak, Colleen; Jasti, Sunitha
2012-01-01
Objective: To assess food label use and skills and to identify their correlates among immigrants from the former Soviet Union (FSU). Design/Setting/Participants: Cross-sectional survey of a convenience sample of 200 FSU immigrants residing in New York City. Variables Measured: Food label use and skills; acculturation; and socioeconomic and…
ERIC Educational Resources Information Center
Spalter-Roth, Roberta; And Others
A study used data for the 1987 calendar year from the 1986 and 1987 panels of the Survey of Income and Program Participation (SIPP) to examine the impact of union membership on women's wages and job tenure. The data set included 17,200 sample members, representing about 79 million workers, aged 16-64. The study mapped the distribution of union…
Gender, Jobs and Working Conditions in the European Union.
ERIC Educational Resources Information Center
Fagan, Colette; Burchell, Brendan
Trends in gender, jobs, and working conditions in the European Union (EU) were examined. In 2000, representative samples of approximately 1,500 workers in each of the EU member states (500 in Luxembourg) were surveyed. To identify trends, the survey findings were compared with those of similar surveys conducted in 1991 and 1996. The comparison…
Haramoto, Eiji; Yamada, Kaoru; Nishida, Kei
2011-12-01
Limited information is available on the prevalence of waterborne pathogens in aquatic environments in developing countries. In this study, water samples were collected from nine shallow wells and a river in the Kathmandu Valley, Nepal, during the rainy season in 2009 and were subjected to detection of waterborne protozoa, viruses and coliphages using a recently developed method for simultaneous concentration of protozoa and viruses in water. Escherichia coli and total coliforms were also tested as indicator bacteria. At least one type of the five pathogens tested (Cryptosporidium, Giardia, human adenoviruses, and noroviruses of genogroups I and II) was detected in five groundwater samples (56%) (1000 ml each) from shallow wells. Compared with groundwater samples, the pathogens were more abundant in the river water sample (100ml); the concentrations of Cryptosporidium and Giardia were 140 oocysts/l and 8500 cysts/l, respectively, and the mean threshold cycle (Ct) values in real-time RT-PCR were 34.3, 36.8 and 34.0 for human adenoviruses and noroviruses of genogroups I and II, respectively. Genotyping of F-RNA coliphages by real-time RT-PCR was successfully used to differentiate human and animal faecal contamination in the samples. Moreover, for the groundwater samples, protozoa and viruses were detected only in E. coli-positive samples, suggesting that E. coli may be an appropriate indicator of pathogen contamination of valley groundwater. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Gellenbeck, Dorinda J.; Anning, David W.
2002-01-01
Samples of ground water and surface water from the Sierra Vista subbasin, the Upper Santa Cruz Basin, and the West Salt River Valley were collected and analyzed to determine the occurrence and distribution of pesticides and volatile organic compounds in central Arizona. The study was done during 1996-98 within the Central Arizona Basins study unit of the National Water-Quality Assessment program. This study included 121 wells and 4 surface-water sites in the 3 basins and the analyses of samples from 4 sites along the Santa Cruz River that were part of a separate study. Samples were collected from 121 wells and 3 surface-water sites for pesticide analyses, and samples were collected from 109 wells and 3 surface-water sites for volatile organic compound analyses. Certain pesticides detected in ground water and surface water can be related specifically to agricultural or urban uses; others can be related to multiple land uses. Effects from historical agriculture are made evident by detections of DDE in ground-water and surface-water samples collected in the West Salt River Valley and detections of atrazine and deethylatrazine in the ground water in the Upper Santa Cruz Basin. Effects from present agriculture are evident in the seasonal variability in concentrations of pre-emergent pesticides in surface-water samples from the West Salt River Valley. Several detections of DDE and dieldrin in surface water were higher than established water-quality limits. Effects of urban land use are made evident by detections of volatile organic compounds in ground water and surface water from the West Salt River Valley. Detections of volatile organic compounds in surface water from the Santa Cruz River near Nogales, Arizona, also are indications of the effects of urban land use. One detection of tetrachloroethene in ground water was higher than established water-quality limits. Water reuse is an important conservation technique in the Southwest; however, the reuse of water provides a transport mechanism for pesticides and volatile organic compounds to reach areas that are not normally affected by manmade compounds from specific land-use activities. The most complex mixture of pesticides and volatile organic compounds is in the West Salt River Valley and is the result of water-management practices and the combination of land uses in this basin throughout history.
Polyfluoroalkyl substance exposure in the Mid-Ohio River Valley, 1991-2012.
Herrick, Robert L; Buckholz, Jeanette; Biro, Frank M; Calafat, Antonia M; Ye, Xiaoyun; Xie, Changchun; Pinney, Susan M
2017-09-01
Industrial discharges of perfluorooctanoic acid (PFOA) to the Ohio River, contaminating water systems near Parkersburg, WV, were previously associated with nearby residents' serum PFOA concentrations above US general population medians. Ohio River PFOA concentrations downstream are elevated, suggesting Mid-Ohio River Valley residents are exposed through drinking water. Quantify PFOA and 10 other per- and polyfluoroalkyl substances (PFAS) in Mid-Ohio River Valley resident sera collected between 1991 and 2013 and determine whether the Ohio River and Ohio River Aquifer are exposure sources. We measured eleven PFAS in 1608 sera from 931 participants. Serum PFOA concentration and water source associations were assessed using linear mixed-effects models. We estimated between-sample serum PFOA using one-compartment pharmacokinetics for participants with multiple samples. In serum samples collected as early as 1991, PFOA (median = 7.6 ng/mL) was detected in 99.9% of sera; 47% had concentrations greater than US population 95th percentiles. Five other PFAS were detected in greater than 82% of samples; median other PFAS concentrations were similar to the US general population. Serum PFOA was significantly associated with water source, sampling year, age at sampling, tap water consumption, pregnancy, gravidity and breastfeeding. Serum PFOA was 40-60% lower with granular activated carbon (GAC) use. Repeated measurements and pharmacokinetics suggest serum PFOA peaked 2000-2006 for participants using water without GAC treatment; where GAC was used, serum PFOA concentrations decreased from 1991 to 2012. Mid-Ohio River Valley residents appear to have PFOA, but not other PFAS, serum concentrations above US population levels. Drinking water from the Ohio River and Ohio River Aquifer, primarily contaminated by industrial discharges 209-666 km upstream, is likely the primary exposure source. GAC treatment of drinking water mitigates, but does not eliminate, PFOA exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.
Thurber, C.; Zhang, H.; Brocher, T.; Langenheim, V.
2009-01-01
We present a three-dimensional (3D) tomographic model of the P wave velocity (Vp) structure of northern California. We employed a regional-scale double-difference tomography algorithm that incorporates a finite-difference travel time calculator and spatial smoothing constraints. Arrival times from earthquakes and travel times from controlled-source explosions, recorded at network and/or temporary stations, were inverted for Vp on a 3D grid with horizontal node spacing of 10 to 20 km and vertical node spacing of 3 to 8 km. Our model provides an unprecedented, comprehensive view of the regional-scale structure of northern California, putting many previously identified features into a broader regional context and improving the resolution of a number of them and revealing a number of new features, especially in the middle and lower crust, that have never before been reported. Examples of the former include the complex subducting Gorda slab, a steep, deeply penetrating fault beneath the Sacramento River Delta, crustal low-velocity zones beneath Geysers-Clear Lake and Long Valley, and the high-velocity ophiolite body underlying the Great Valley. Examples of the latter include mid-crustal low-velocity zones beneath Mount Shasta and north of Lake Tahoe. Copyright 2009 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Dansie, Andrew; Wiggs, Giles; Thomas, David
2016-04-01
Oceanic dust deposition provides biologically important iron and macronutrients (Phosphorus (P) and Nitrogen-based (N) compounds) that contribute to phytoplankton growth, marine productivity and oceanic atmospheric CO2 uptake. Research on dust emission sources to date has largely focused on the northern hemisphere and on ephemeral lakes and pans. Our work considers the ephemeral river valleys of the west coast of Namibia as an important yet overlooked source of ocean-fertilizing dust. Dust plumes are frequently emitted from the river valleys by strong easterly winds during the Southern Hemisphere winter, when the upwelling of the Benguela Current is at its weakest. We present field data from dust emission source areas along the main river channels near the coastal termini of the Huab, Kuiseb and Tsauchab river valleys. Collected data include erodible surface sediment, wind-blown flux, and associated meteorological data. Extensive surface sediment sampling was also undertaken throughout the combined 34,250 km2 extent of each river valley catchment with samples collected from within the main river channels, the main branches of each river system, selected tributaries, and into the upper watersheds. Geochemical data show valley sediment and wind-blown flux material have high concentrations of bioavailable Fe, P and N, exceeding that measured at the major dry lake basin dust sources in southern Africa. The contribution of fertilising deposition material is enhanced by both the spatial proximity of the source areas to the ocean and enrichment of source material by ephemeral fluvial accumulation and desiccation. Results show that geographical factors within each watershed play a key role in the nutrient composition of the emitting fluvial deposits in the river valleys. Analysis explores potential relationships between land use, geology, climate and precipitation in the upper watersheds and their influence on bioavailability of Fe, P and N compounds in wind-erodible valley sediments. MODIS data for dust plume identification and chlorophyll concentration in the southern Atlantic is utilised to investigate associations between recorded dust emission events and phytoplankton growth in the ocean surface waters.
Trade unionism in the information technology (IT) industry: an employee's perspective.
Dhar, Rajib Lochan
2012-01-01
This research aimed to understand the information technology (IT) employees' perception and approach towards union formation in the Indian IT Industry. Fifty IT professionals from three different organizations participated in this study who were dispersed throughout the organizational hierarchy and were selected via randomized quota sampling to reflect a mix of age, experience, gender and position they held with the organization. Qualitative methods were used in order to collect the data, through phenomenological principles. Discussion with the participants led to the emergence of four themes which influence the employees' perception of trade union formation the Indian IT industry. These were: (a) feeling of a blue collar, (b) collective to individual bargaining, (c) changing role of HR and (d) other reasons. This study provided a tentative starting point towards the greater understanding of the employee's perceived notion of organizational life that influences employee's outlook towards trade unionism. Based on the study findings, there is an imperative that the human resource department, organizational forerunners and trade union philosophers continue to use research findings to understand employees' views about union formation in the IT industry.
NASA Astrophysics Data System (ADS)
Guido, Zackry S.; Ward, Dylan J.; Anderson, Robert S.
2007-08-01
During the Last Glacial Maximum (LGM), a 5000 km2 ice cap covered the San Juan Mountains of southwest Colorado. The largest valley glacier draining this ice cap occupied the Animas Valley and flowed 91 km to the south. To characterize the post-LGM demise of the Animas Valley glacier, we employ cosmogenic 10Be to date the LGM terrace outside the terminal moraines and a suite of seven glacially polished bedrock samples. The 10Be depth profile within the terrace sediments suggests abandonment at 19.4 ± 1.5 ka. As deglaciation began, the ponding of Glacial Lake Durango behind the terminal moraines shut off fluvial sediment supply and caused terrace abandonment. The age of the terrace therefore records the initiation of LGM retreat. Negligible 10Be inheritance in the terrace profile suggests that glacial erosion of the bedrock valley floor from which sediments were derived erased all cosmogenic inventory. Glacial polish exposure ages monotonically decrease up-valley from 17.1 to 12.3 ka, with the single exception of a sample collected from a quartzite rib, yielding an average retreat rate of 15.4 m/yr. This trend and the lack of inherited cosmogenic nuclides in the terrace sediments imply that polish ages accurately record the glacial retreat history. Retreat of the Animas lobe began at a time of regional drying recorded in sediments and shoreline elevations of large lakes. Deglaciation lasted for ˜7.2 k.y., and was complete by 12.3 ± 1.0 ka. The retreat history followed the pattern of increasing insolation and was perhaps fastest during a time of regional drying.
Zamora, Celia; Majewski, Michael S.; Foreman, William T.
2013-01-01
The U.S. Geological Survey monitored atmospheric deposition of pesticides in the Central Valley of California during two studies in 2001 and 2002–04. The 2001 study sampled wet deposition (rain) and storm-drain runoff in the Modesto, California, area during the orchard dormant-spray season to examine the contribution of pesticide concentrations to storm runoff from rainfall. In the 2002–04 study, the number and extent of collection sites in the Central Valley were increased to determine the areal distribution of organophosphate insecticides and other pesticides, and also five more sample types were collected. These were dry deposition, bulk deposition, and three sample types collected from a soil box: aqueous phase in runoff, suspended sediment in runoff, and surficial-soil samples. This report provides concentration data and describes methods and quality assurance of sample collection and laboratory analysis for pesticide compounds in all samples collected from 16 sites. Each sample was analyzed for 41 currently used pesticides and 23 pesticide degradates, including oxygen analogs (oxons) of 9 organophosphate insecticides. Analytical results are presented by sample type and study period. The median concentrations of both chloryprifos and diazinon sampled at four urban (0.067 micrograms per liter [μg/L] and 0.515 μg/L, respectively) and four agricultural sites (0.079 μg/L and 0.583 μg/L, respectively) during a January 2001 storm event in and around Modesto, Calif., were nearly identical, indicating that the overall atmospheric burden in the region appeared to be fairly similar during the sampling event. Comparisons of median concentrations in the rainfall to those in the McHenry storm-drain runoff showed that, for some compounds, rainfall contributed a substantial percentage of the concentration in the runoff; for other compounds, the concentrations in rainfall were much greater than in the runoff. For example, diazinon concentrations in rainfall were about 70 percent of the diazinon concentration in the runoff, whereas the chlorpyrifos concentration in the rain was 1.8 times greater than in the runoff. The more water-soluble pesticides—carbaryl, metolachlor, napropamide, and simazine—followed the same pattern as diazinon and had lower concentrations in rain compared to runoff. Similar to chlorpyrifos,compounds with low water solubilities and higher soil-organic carbon partition coefficients, including dacthal, pendimethalin, and trifluralin, were found to have higher concentrations in rain than in runoff water and were presumed to partition to the suspended sediments and organic matter on the ground. During the 2002–04 study period, the herbicide dacthal had the highest detection frequencies for all sample types collected from the Central Valley sites (67–100 percent). The most frequently detected compounds in the wet-deposition samples were dacthal, diazinon, chlorpyrifos, and simazine (greater than 90 percent). The median wet-deposition amounts for these compounds were 0.044 micrograms per square meter per day (μg/m2/day), 0.209 μg/m2/day, 0.079 μg/m2/day, and 0.172 μg/m2/day, respectively. For the dry-deposition samples, detection frequencies were greater than 73 percent for the compounds dacthal, metolachor, and chlorpyrifos, and median deposition amounts were an order of magnitude less than for wet deposition. The differences between wet deposition and dry deposition appeared to be closely related to the Henry’s Law (H) constant of each compound, although the mass deposited by dry deposition takes place over a much longer time frame. Pesticides detected in rainfall usually were detected in the aqueous phase of the soil-box runoff water, and the runoff concentrations were generally similar to those in the rainfall. For compounds detected in the aqueous phase and suspended-sediment samples of soil-box runoff, concentrations of pesticides in the aqueous phase generally were detected in low concentrations and had few corresponding detections in the suspended- sediment samples. Dacthal, diazinon, chlorpyrifos, and simazine were the most frequently detected pesticides (greater than 83 percent) in the aqueous-phase samples, with median concentrations of 0.010 μg/L, 0.045 μg/L, 0.016 μg/L, and 0.077 μg/L, respectively. Simazine was the most frequently detected compound in the suspended-sediment samples (69 percent), with a median concentration of 0.232 μg/L. Results for compounds detected in the surficial-soil samples collected throughout the study period showed that there was an increase in concentration for some compounds, indicating atmospheric deposition of these compounds onto the soil-box surface. In the San Joaquin Valley, the compounds chlorpyrifos, dacthal, and iprodione were detected at higher concentrations (between 1.4 and 2 times greater) than were found in the background samples collected from the San Joaquin Valley soil-box sites. In the Sacramento Valley, the compounds chlorpyrifos, dacthal, iprodione, parathionmethyl, and its oxygen analog, paraoxon-methyl, were detected in samples collected during the study period in low concentrations, but were not detected in the background concentration of the Sacramento Valley soil mix.
Uranium and radon in ground water in the lower Illinois River basin
Morrow, William S.
2001-01-01
Uranium and radon are present in ground water throughout the United States, along with other naturally occurring radionuclides. The occurrence and distribution of uranium and radon are of concern because these radionuclides are carcinogens that can be ingested through drinking water. As part of the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program, water samples were collected and analyzed for uranium and radon from 117 wells in four aquifers in the lower Illinois River Basin (LIRB) from 1996 to 1997. The aquifers were the shallow glacial drift deposits of the Bloomington Ridged Plain (BRP) not overlying a buried bedrock valley (BRP N/O BV), shallow glacial drift deposits of the BRP overlying the Mahomet Buried Bedrock Valley (BRP O/L MBBV), shallow glacial drift deposits of the Galesburg/Springfield Plain not overlying a buried bedrock valley (GSP N/O BV), and the deep glacial drift deposits of the Mahomet Buried Bedrock Valley (MBBV). Uranium was detected in water samples from all aquifers except the MBBV and ranged in concentration from less than 1 microgram per liter ( ? g/L) to 17 ? g/L. Uranium concentrations did not exceed 20 ? g/L, the proposed U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Level (MCL) at the time of sampling (1996?97). The current (2001) promulgated MCL is 30 ? g/L (U.S. Environmental Protection Agency, 2000). The highest median uranium concentration (2.0 ? g/L) among the four aquifers was in the BRP N/O BV. Uranium most often occurred in oxidizing and sulfate-rich water. Radon was detected in water samples from all aquifers in the LIRB. Radon concentrations in all aquifers ranged from less than 80 picocuries per liter (pCi/L) to 1,300 pCi/L. Of 117 samples, radon concentrations exceeded 300 pCi/L (the proposed USEPA MCL) in 34 percent of the samples. Radon concentrations exceeded 300 pCi/L in more than one-half of the samples from the GSP N/O BV and the BRP O/L MBBV. No sample exceeded the proposed Alternative Maximum Contaminant Level (AMCL) of 4,000 pCi/L. Concentrations of uranium and radon were not correlated.
Calibration of numerical models for small debris flows in Yosemite Valley, California, USA
Bertolo, P.; Wieczorek, G.F.
2005-01-01
This study compares documented debris flow runout distances with numerical simulations in the Yosemite Valley of California, USA, where about 15% of historical events of slope instability can be classified as debris flows and debris slides (Wieczorek and Snyder, 2004). To model debris flows in the Yosemite Valley, we selected six streams with evidence of historical debris flows; three of the debris flow deposits have single channels, and the other three split their pattern in the fan area into two or more channels. From field observations all of the debris flows involved coarse material, with only very small clay content. We applied the one dimensional DAN (Dynamic ANalysis) model (Hungr, 1995) and the two-dimensional FLO2D model (O'Brien et al., 1993) to predict and compare the runout distance and the velocity of the debris flows observed in the study area. As a first step, we calibrated the parameters for the two softwares through the back analysis of three debris- flows channels using a trial-and-error procedure starting with values suggested in the literature. In the second step we applied the selected values to the other channels, in order to evaluate their predictive capabilities. After parameter calibration using three debris flows we obtained results similar to field observations We also obtained a good agreement between the two models for velocities. Both models are strongly influenced by topography: we used the 30 m cell size DTM available for the study area, that is probably not accurate enough for a highly detailed analysis, but it can be sufficient for a first screening. European Geosciences Union ?? 2005 Author(s). This work is licensed under a Creative Commons License.
New constraints on mechanisms of remotely triggered seismicity at Long Valley Caldera
Brodsky, E.E.; Prejean, S.G.
2005-01-01
Regional-scale triggering of local earthquakes in the crust by seismic waves from distant main shocks has now been robustly documented for over a decade. Some of the most thoroughly recorded examples of repeated triggering of a single site from multiple, large earthquakes are measured in geothermal fields of the western United States like Long Valley Caldera. As one of the few natural cases where the causality of an earthquake sequence is apparent, triggering provides fundamental constraints on the failure processes in earthquakes. We show here that the observed triggering by seismic waves is inconsistent with any mechanism that depends on cumulative shaking as measured by integrated energy density. We also present evidence for a frequency-dependent triggering threshold. On the basis of the seismic records of 12 regional and teleseismic events recorded at Long Valley Caldera, long-period waves (>30 s) are more effective at generating local seismicity than short-period waves of comparable amplitude. If the properties of the system are stationary over time, the failure threshold for long-period waves is ~0.05 cm/s vertical shaking. Assuming a phase velocity of 3.5 km/s and an elastic modulus of 3.5 x 1010Pa, the threshold in terms of stress is 5 kPa. The frequency dependence is due in part to the attenuation of the surface waves with depth. Fluid flow through a porous medium can produce the rest of the observed frequency dependence of the threshold. If the threshold is not stationary with time, pore pressures that are >99.5% of lithostatic and vary over time by a factor of 4 could explain the observations with no frequency dependence of the triggering threshold. Copyright 2005 by the American Geophysical Union.
Three-dimensional P wave velocity model for the San Francisco Bay region, California
Thurber, C.H.; Brocher, T.M.; Zhang, H.; Langenheim, V.E.
2007-01-01
A new three-dimensional P wave velocity model for the greater San Francisco Bay region has been derived using the double-difference seismic tomography method, using data from about 5,500 chemical explosions or air gun blasts and approximately 6,000 earthquakes. The model region covers 140 km NE-SW by 240 km NW-SE, extending from 20 km south of Monterey to Santa Rosa and reaching from the Pacific coast to the edge of the Great Valley. Our model provides the first regional view of a number of basement highs that are imaged in the uppermost few kilometers of the model, and images a number of velocity anomaly lows associated with known Mesozoic and Cenozoic basins in the study area. High velocity (Vp > 6.5 km/s) features at ???15-km depth beneath part of the edge of the Great Valley and along the San Francisco peninsula are interpreted as ophiolite bodies. The relocated earthquakes provide a clear picture of the geometry of the major faults in the region, illuminating fault dips that are generally consistent with previous studies. Ninety-five percent of the earthquakes have depths between 2.3 and 15.2 km, and the corresponding seismic velocities at the hypocenters range from 4.8 km/s (presumably corresponding to Franciscan basement or Mesozoic sedimentary rocks of the Great Valley Sequence) to 6.8 km/s. The top of the seismogenic zone is thus largely controlled by basement depth, but the base of the seismogenic zone is not restricted to seismic velocities of ???6.3 km/s in this region, as had been previously proposed. Copyright 2007 by the American Geophysical Union.
Muhs, D.R.; Budahn, J.R.; Prospero, J.M.; Carey, S.N.
2007-01-01
We studied soils on high-purity limestones of Quaternary age on the western Atlantic Ocean islands of Barbados, the Florida Keys, and the Bahamas. Potential soil parent materials in this region, external to the carbonate substrate, include volcanic ash from the island of St. Vincent (near Barbados), volcanic ash from the islands of Dominica and St. Lucia (somewhat farther from Barbados), the fine-grained component of distal loess from the lower Mississippi River Valley, and wind-transported dust from Africa. These four parent materials can be differentiated using trace elements (Sc, Cr, Th, and Zr) and rare earth elements that have minimal mobility in the soil-forming environment. Barbados soils have compositions that indicate a complex derivation. Volcanic ash from the island of St. Vincent appears to have been the most important influence, but African dust is a significant contributor, and even Mississippi River valley loess may be a very minor contributor to Barbados soils. Soils on the Florida Keys and islands in the Bahamas appear to have developed mostly from African dust, but Mississippi River valley loess may be a significant contributor. Our results indicate that inputs of African dust are more important to the genesis of soils on islands in the western Atlantic Ocean than previously supposed. We hypothesize that African dust may also be a major contributor to soils on other islands of the Caribbean and to soils in northern South America, central America, Mexico, and the southeastern United States. Dust inputs to subtropical and tropical soils in this region increase both nutrient-holding capacity and nutrient status and thus may be critical in sustaining vegetation. Copyright 2007 by the American Geophysical Union.
Mars Exploration Program 2007 Phoenix landing site selection and characteristics
Arvidson, R.; Adams, D.; Bonfiglio, G.; Christensen, P.; Cull, S.; Golombek, M.; Guinn, J.; Guinness, E.; Heet, T.; Kirk, R.; Knudson, A.; Malin, M.; Mellon, M.; McEwen, A.; Mushkin, A.; Parker, T.; Seelos, F.; Seelos, K.; Smith, P.; Spencer, D.; Stein, T.; Tamppari, L.
2009-01-01
To ensure a successful touchdown and subsequent surface operations, the Mars Exploration Program 2007 Phoenix Lander must land within 65?? to 72?? north latitude, at an elevation less than -3.5 km. The landing site must have relatively low wind velocities and rock and slope distributions similar to or more benign than those found at the Viking Lander 2 site. Also, the site must have a soil cover of at least several centimeters over ice or icy soil to meet science objectives of evaluating the environmental and habitability implications of past and current near-polar environments. The most challenging aspects of site selection were the extensive rock fields associated with crater rims and ejecta deposits and the centers of polygons associated with patterned ground. An extensive acquisition campaign of Odyssey Thermal Emission Imaging Spectrometer predawn thermal IR images, together with ???0.31 m/pixel Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment images was implemented to find regions with acceptable rock populations and to support Monte Carlo landing simulations. The chosen site is located at 68.16?? north latitude, 233.35?? east longitude (areocentric), within a ???50 km wide (N-S) by ???300 km long (E-W) valley of relatively rock-free plains. Surfaces within the eastern portion of the valley are differentially eroded ejecta deposits from the relatively recent ???10-km-wide Heimdall crater and have fewer rocks than plains on the western portion of the valley. All surfaces exhibit polygonal ground, which is associated with fracture of icy soils, and are predicted to have only several centimeters of poorly sorted basaltic sand and dust over icy soil deposits. Copyright 2008 by the American Geophysical Union.
Halstead, Brian J.; Skalos, Shannon M.; Casazza, Michael L.; Wylie, Glenn D.
2015-09-30
Giant gartersnakes (Thamnophis gigas) comprise a species of rare, semi-aquatic snake precinctive to the Central Valley of California. Because of the loss of more than 90% of their natural habitat, giant gartersnakes are listed as Threatened by the United States and California endangered species acts. Little is known, however, about the distribution of giant gartersnakes in the Sacramento Valley, which is where most extant populations occur. We conducted detection-nondetection surveys for giant gartersnakes throughout the rice-growing regions of the Sacramento Valley, and used occupancy models to examine evidence for the effects of landscape-scale GIS-derived variables, local habitat and vegetation composition, and prey communities on patterns of giant gartersnake occurrence. Although our results are based on a relatively small sample of sites, we found that distance to historic marsh, relative fish count, and an interaction of distance to historic marsh with proportion of habitat composed of submerged vegetation were important variables for explaining occupancy of giant gartersnakes. In particular, giant gartersnakes were more likely to occur closer to historic marsh and where relatively fewer fish were captured in traps. At locations in or near historic marsh, giant gartersnakes were more likely to occur in areas with less submerged vegetation, but this relationship was reversed (and more uncertain) at sites distant from historic marsh. Additional research with a larger sample of sites would further elucidate the distribution of giant gartersnakes in the Sacramento Valley.
Ground-water quality in east-central Idaho valleys
Parliman, D.J.
1982-01-01
From May through November 1978, water quality, geologic, and hydrologic data were collected for 108 wells in the Lemhi, Pahsimeroi, Salman River (Stanley to Salmon), Big Lost River, and Little Lost River valleys in east-central Idaho. Data were assembled to define, on a reconnaissance level, water-quality conditions in major aquifers and to develop an understanding of factors that affected conditions in 1978 and could affect future ground-water quality. Water-quality characteristics determined include specific conductance, pH, water temperature, major dissolved cations, major dissolved anions, and coliform bacteria. Concentrations of hardness, nitrite plus nitrate, coliform bacteria, dissolved solids, sulfate, chloride, fluoride , iron, calcium, magnesium, sodium, potassium or bicarbonate exceed public drinking water regulation limits or were anomalously high in some water samples. Highly mineralized ground water probably is due to the natural composition of the aquifers and not to surface contamination. Concentrations of coliform bacteria that exceed public drinking water limits and anomalously high dissolved nitrite-plus-nitrite concentrations are from 15- to 20-year old irrigation wells in heavily irrigated or more densely populated areas of the valleys. Ground-water quality and quantity in most of the study area are sufficient to meet current (1978) population and economic demands. Ground water in all valleys is characterized by significant concentrations of calcium, magnesium, and bicarbonate plus carbonate ions. Variations in the general trend of ground-water composition (especially in the Lemhi Valley) probably are most directly related to variability in aquifer lithology and proximity of sampling site to source of recharge. (USGS)
NNSS Soils Monitoring: Plutonium Valley (CAU 366) FY2013 and FY2014
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miller, Julianne J.; Nikolich, George; Mizell, Steve
The Desert Research Institute (DRI) is conducting a field assessment of the potential for contaminated soil transport from the Plutonium Valley Contamination Area (CA) as a result of wind transport and storm runoff in support of Nevada Nuclear Security Administration (NNSA) efforts to complete regulatory closure of the contamination areas. The DRI work is intended to confirm the likely mechanism(s) of transport and determine the meteorological conditions that might cause movement of contaminated soils. Emphasis is given to collecting sediment transported by channelized storm runoff at the Plutonium Valley investigation sites. These data will inform closure plans that are beingmore » developed, which will facilitate appropriate closure design and postclosure monitoring. Desert Research Institute installed two meteorological monitoring stations south (station number 1) and north (station number 2) of the Plutonium Valley CA and a runoff sediment sampling station within the CA in 2011. Temperature, wind speed, wind direction, relative humidity, precipitation, solar radiation, barometric pressure, soil temperature, and airborne particulate concentration are collected at both meteorological stations. The maximum, minimum, and average or total (as appropriate) for each of these parameters is recorded for each 10-minute interval. The sediment sampling station includes an automatically activated ISCO sampling pump with collection bottles for suspended sediment, which is activated when sufficient flow is present in the channel, and passive traps for bedload material that is transported down the channel during runoff events. This report presents data collected from these stations during FY2013 and FY2014.« less
NNSS Soils Monitoring: Plutonium Valley (CAU 366) FY2015
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nikolich, George; Mizell, Steve; McCurdy, Greg
Desert Research Institute (DRI) is conducting a field assessment of the potential for contaminated soil transport from the Plutonium Valley Contamination Area (CA) as a result of wind transport and storm runoff in support of National Nuclear Security Administration (NNSA) efforts to complete regulatory closure of the contamination areas. The DRI work is intended to confirm the likely mechanism(s) of transport and determine the meteorological conditions that might cause movement of contaminated soils. The emphasis of the work is on collecting sediment transported by channelized storm runoff at the Plutonium Valley investigation sites. These data will inform closure plans thatmore » are being developed, which will facilitate the appropriate closure design and post-closure monitoring. In 2011, DRI installed two meteorological monitoring stations south (station #1) and north (station #2) of the Plutonium Valley CA and a runoff sediment sampling station within the CA. Temperature, wind speed, wind direction, relative humidity, precipitation, solar radiation, barometric pressure, soil temperature, and airborne particulate concentration are collected at both meteorological stations. The maximum, minimum, and average or total (as appropriate) for each of these parameters are recorded for each 10-minute interval. The sediment sampling station includes an automatically activated ISCO sampling pump with collection bottles for suspended sediment, which is activated when sufficient flow is present in the channel, and passive traps for bedload material that is transported down the channel during runoff events. This report presents data collected from these stations during fiscal year (FY) 2015.« less
Procapra picticaudata (Artiodactyla: Bovidae)
Leslie, David M.
2010-01-01
Procapra picticaudata Hodgson, 1846, is commonly called the Tibetan gazelle, goa (= Tibetan), or zang yuan ling (= Chinese) and is monotypic. It is a high-elevation specialist endemic to the Tibetan Plateau where it prefers alpine meadow and alpine steppe but uses other lower-elevation plains and valleys. It is partial to good grasslands with high diversity of forbs. There have been no systematic estimates of total numbers of P. picticaudata. Populations are currently widespread but have been reduced from historic levels and are vulnerable because of poaching in remote areas and competition with livestock of pastoralists. P. picticaudata is uncommon in zoos and private collections. It is a threatened Class II species in China and considered “Near Threatened" by the International Union for Conservation of Nature and Natural Resources.
Hayes, Timothy S.; Mustafa, Mazin; Bennet, Thair
2014-01-01
Reconnaissance field visits and rock sampling were conducted at eight geologically selected locations within Mesozoic rocks on the eastern flank of the Rutbah Uplift, Anbar Province, western Iraq, in an attempt to determine if these rocks have been affected by a Mississippi Valley-Type (MVT) lead-zinc mineralizing system. Samples subsequently were studied by carbonate mineral staining, transmitted and reflected light petrology, and scanning electron microscopy with semi-quantitative energy dispersive elemental analyses. Single samples were studied by each, inductively coupled plasma mass spectrometry analyses of trace elements and fluid inclusion microthermometry. Permissive evidence indicates that there has been a MVT system present, but none of the evidence is considered definitive.
Serological tests for detecting Rift Valley fever viral antibodies in sheep from the Nile Delta.
Scott, R M; Feinsod, F M; Allam, I H; Ksiazek, T G; Peters, C J; Botros, B A; Darwish, M A
1986-01-01
To determine the accuracy of serological methods in detecting Rift Valley fever (RVF) viral antibodies, we examined serum samples obtained from 418 sheep in the Nile Delta by using five tests. The plaque reduction neutralization test (PRNT) was considered the standard serological method against which the four other tests were compared. Twenty-four serum samples had RVF viral antibodies detected by PRNT. Hemagglutination inhibition and enzyme-linked immunosorbent assay antibodies to RVF virus were also present in the same 24 serum samples. Indirect immunofluorescence was less sensitive in comparison with PRNT, and complement fixation was the least sensitive. These results extend observations made with laboratory animals to a large field-collected group of Egyptian sheep. PMID:3533977
Draft Genome Sequence of a Red-Pigmented Janthinobacterium sp. Native to the Hudson Valley Watershed
O’Brien, Kelsey
2018-01-01
ABSTRACT Water samples from the Hudson Valley watershed indicate that the area is host to many violacein-producing bacterial isolates. Here, we report the draft whole-genome sequence of Janthinobacterium sp. strain BJB412, an isolate lacking violacein production yet containing genes responsible for prodigiosin, biofilm production, and quorum sensing, like its purple-pigmented counterparts. PMID:29301893
ERIC Educational Resources Information Center
Jones, Paul; Miller, Christopher; Pickernell, David; Packham, Gary
2011-01-01
Purpose: The objective of this paper is to examine the initiation of the University of the Heads of the Valley Initiative (UHOVI) project and evaluate the development of its focus, materials and structure. Design/methodology/approach: The methodology employs interviews with a purposive sample of local employer stakeholders. The rationale for this…
Stand development of trembling aspen in Canaan Valley, West Virginia
James S. Rentch; James T. Anderson
2008-01-01
In wetlands of Canaan Valley, West Virginia, trembling aspen occurs as a disjunct population well south of its primary natural range. Based on sample data from 15 stands, we found that aspen occurs as nearly monospecific stands or clones. Eight stands had median ages between 30 and 40 yrs, and we suggest that stand initiation was related to changes in land use after...
Mineralogy of Drill Cuttings Beowawe, Dixie Valley and Roosevelt Hot Springs
Simmons, Stuart
2017-01-25
Mineralogical, lithological, and geospatial data of drill cuttings from exploration production wells in Beowawe, Dixie Valley and Roosvelt Hot Springs. These data support whole rock analyses for major, minor and critical elements to assess critical metals in produced fluids from Nevada and Utah geothermal fields. The samples were analyzed by x-ray diffraction (legacy data) and then checked by thin section analysis.
Wilkins, D.W.; Schlottmann, J.L.; Ferree, D.M.
1996-01-01
A study was conducted to investigate general ground-water- quality conditions and contaminant locations in the Rio Grande Valley in the vicinity of Albuquerque, New Mexico. Water samples from 36 observation wells in 12 well nests were analyzed. The well nests are located along three roads near the Rio Grande--two well nests near Paseo del Norte, five well nests near Monta?o Road, and five well nests near Rio Bravo Boulevard. The water samples were collected from October 19, 1993, through January 18, 1994. Water-quality types by major-ion composition were calcium bicarbonate (found in most samples), sodium sulfate, calcium sulfate, and calcium sulfate chloride. Nutrients were detected in all but one sample. Ammonia was detected in 34 samples, nitrite in 4 samples, and nitrate in 17 samples. Orthophosphate was detected in 31 samples. Organic carbon was detected in all samples collected. The trace elements arsenic and barium were detected in all samples and zinc in 31 samples. Fourteen samples contained detectable copper. Cadmium was detected in one sample, chromium in two samples, lead in four samples, and selenium in two samples. Mercury and silver were not detected.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
In the Bear Creek Valley Watershed Remedial Investigation, the Boneyard/Burnyard was identified as the source of the largest releases of uranium into groundwater and surface water in Bear Creek Valley. The proposed action for remediation of this site is selective excavation and removal of source material and capping of the remainder of the site. The schedule for this action has been accelerated so that this is the first remedial action planned to be implemented in the Bear Creek Valley Record of Decision. Additional data needs to support design of the remedial action were identified at a data quality objectives meetingmore » held for this project. Sampling at the Boneyard/Burnyard will be conducted through the use of a phased approach. Initial or primary samples will be used to make in-the-field decisions about where to locate follow-up or secondary samples. On the basis of the results of surface water, soil, and groundwater analysis, up to six test pits will be dug. The test pits will be used to provide detailed descriptions of source materials and bulk samples. This document sets forth the requirements and procedures to protect the personnel involved in this project. This document also contains the health and safety plan, quality assurance project plan, waste management plan, data management plan, implementation plan, and best management practices plan for this project as appendices.« less
[Genetic composition of Chilean population: rural communities of Elqui, Limari and Choapa valleys].
Acuña, M; Llop, E; Rothhammer, F
2000-06-01
The population that inhabits the semiarid Northern zone of Chile arose from ethnic admixture between aborigines, Spanish conquerors and the influx, during the XVII century, of foreign aboriginal workers and a minority of African slaves. To study the phenotypic frequencies of 15 genetic markers among populations inhabiting valleys in the Northern zone of Chile and to estimate the percentage of indigenous, African and Caucasian admixture in these populations. Throughout five different field works, blood samples were obtained from 120 individuals living in the Elqui valley, 120 individuals living in the Limari valley and 85 living in the Choapa valley. Blood groups, erythrocyte enzymes, plasma proteins and HLA markers were typified. In the populations studied, the contribution of non indigenous genes was low in relation with the time elapsed since the Spanish invasion. The Hardy-Weinberg disequilibrium for MNS system would have microevolutive implications. The admixture percentages in these valleys confirm ethnic and historic information. The variation of the enzyme esterase D is identical to that of other Chilean populations. The phenotypic and genetic frequencies in the three populations studied and different admixture of indigenous genes is inversely proportional to the geographic distance from Santiago, in Central Chile.
Colson, Aaron J; Vredenburgh, Larry; Guevara, Ramon E; Rangel, Natalia P; Kloock, Carl T; Lauer, Antje
2017-06-01
Ongoing large-scale land development for renewable energy projects in the Antelope Valley, located in the Western Mojave Desert, has been blamed for increased fugitive dust emissions and coccidioidomycosis incidence among the general public in recent years. Soil samples were collected at six sites that were destined for solar farm construction and were analyzed for the presence of the soil-borne fungal pathogen Coccidioides immitis which is endemic to many areas of central and southern California. We used a modified culture-independent nested PCR approach to identify the pathogen in all soil samples and also compared the sampling sites in regard to soil physical and chemical parameters, degree of disturbance, and vegetation. Our results indicated the presence of C. immitis at four of the six sites, predominantly in non-disturbed soils of the Pond-Oban complex, which are characterized by an elevated pH and salt bush communities, but also in grassland characterized by different soil parameters and covered with native and non-native annuals. Overall, we were able to detect the pathogen in 40% of the soil samples (n = 42). Incidence of coccidioidomycosis in the Antelope Valley was positively correlated with land use and particulate matter in the air (PM10) (Pearson correlation coefficient >0.5). With the predicted population growth and ongoing large-scale disturbance of soil in the Antelope Valley in coming years, incidence of coccidioidomycosis will likely further increase if policy makers and land developers continue to ignore the risk of grading land without implementing long-term dust mitigation plans in Environmental Impact Reports.
Sampling methods for microbiological analysis of red meat and poultry carcasses.
Capita, Rosa; Prieto, Miguel; Alonso-Calleja, Carlos
2004-06-01
Microbiological analysis of carcasses at slaughterhouses is required in the European Union for evaluating the hygienic performance of carcass production processes as required for effective hazard analysis critical control point implementation. The European Union microbial performance standards refer exclusively to the excision method, even though swabbing using the wet/dry technique is also permitted when correlation between both destructive and nondestructive methods can be established. For practical and economic reasons, the swab technique is the most extensively used carcass surface-sampling method. The main characteristics, advantages, and limitations of the common excision and swabbing methods are described here.
NASA Astrophysics Data System (ADS)
Peters, Bradley J.; Day, James M. D.; Taylor, Lawrence A.
2016-08-01
Ultramafic cumulate rocks form during intrusive crystallization of high-MgO magmas, incorporating relatively high abundances of compatible elements, including Cr and Ni, and high abundances of the highly siderophile elements (HSE: Os, Ir, Ru, Pt, Pd, Re). Here, we utilize a suite of cumulate xenoliths from Piton de la Fournaise, La Réunion (Indian Ocean), to examine the mantle source composition of the Réunion hotspot using HSE abundances and Os isotopes. Dunite and wherlite xenoliths and associated lavas from the Piton de la Fournaise volcanic complex span a range of MgO contents (46 to 7 wt.%), yet exhibit remarkably homogeneous 187Os/188Os (0.1324 ± 0.0014, 2σ), representing the Os-isotopic composition of Réunion hotspot primary melts. A significant fraction of the xenoliths also have primitive upper-mantle (PUM) normalized HSE patterns with elevated Ru and Pd (PUM-normalized Ru/Ir and Pd/Ir of 0.8-6.3 and 0.2-7.2, respectively). These patterns are not artifacts of alteration, fractional crystallization, or partial melting processes, but rather require a primary magma with similar relative enrichments. Some highly olivine-phyric (>40 modal percent olivine) Piton de la Fournaise lavas also preserve these relative Ru and Pd enrichments, while others preserve a pattern that is likely related to sulfur saturation in evolved melts. The estimate of HSE abundances in PUM indicates high Ru/Ir and Pd/Pt values relative to carbonaceous, ordinary and enstatite chondrite meteorite groups. Thus, the existence of cumulate rocks with even more fractionated HSE patterns relative to PUM suggests that the Réunion hotspot samples a yet unrecognized mantle source. The origin of fractionated HSE patterns in Réunion melts may arise from sampling of a mantle source that experienced limited late accretion (<0.2% by mass) compared with PUM (0.5-0.8%), possibly involving impactors that were distinct from present-day chondrites, or limited core-mantle interactions. Given the remarkably homogeneous Os, Pb, and noble-gas isotopic signatures of Réunion, which plot near the convergence point of isotopic data for many hotspots, such a conclusion provides evidence for an early differentiated and subsequently isolated mantle domain that may be partially sampled by some ocean island basalts.
Transport anomalies of high-mobility Q-valley electrons in few-layer WS2 and MoS2
NASA Astrophysics Data System (ADS)
Wang, Ning
Atomically thin transition metal dichalcogenides (TMDCs) have opened new avenues for exploring physical property anomalies due to their large band gaps, strong spin-orbit couplings, and rich valley degrees of freedom. Although novel optical phenomena such as valley selective circular dichroism, opto-valley Hall effect, and valley Zeeman effect have been extensively studied in TMDCs, investigation of quantum transport properties has encountered a number of obstacles primarily due to the low carrier mobility and strong impurity scattering. Recently, we successfully fabricated ultrahigh-mobility few-layer TMDC field-effect transistors based on the boron nitride encapsulation method and observed a number of interesting transport properties, such as even-odd layer-dependent magnetotransport of Q-valley electrons in WS2 and MoS2 and unconventional quantum Hall transport of Γ-valley hole carriers in WSe2. In few-layer samples of these TMDCs, the conduction bands along the ΓK directions shift downward energetically in the presence of interlayer interactions, forming six Q-valleys related by three-fold rotational symmetry and time reversal symmetry. In even-layers the extra inversion symmetry requires all states to be Kramers degenerate, whereas in odd-layers the intrinsic inversion asymmetry dictates the Q-valleys to be spin-valley coupled. In this talk, I'll demonstrate the prominent Shubnikov-de Hass (SdH) oscillations and the observation of the onset of quantum Hall plateaus for the Q-valley electrons. Universally in the SdH oscillations, we observe a valley Zeeman effect in all odd-layer TMDC devices and a spin Zeeman effect in all even-layer TMDC devices. In addition, we observe a series of quantum Hall states following an unconventional sequence predominated by odd-integer states under a moderate strength magnetic field in p-type few-layer TMDCs, indicating a large Zeeman energy associated with the carriers in the valence band at the Γ-valley. Financial supports from the Research Grants Council of Hong Kong (Project Nos. 16302215, HKU9/CRF/13G, 604112 and N-HKUST613/12) are hereby acknowledged.
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.
Serological status of Canadian cattle for brucellosis, anaplasmosis, and bluetongue in 2007–2008
Paré, Julie; Geale, Dorothy W.; Koller-Jones, Maria; Hooper-McGrevy, Kathleen; Golsteyn-Thomas, Elizabeth J.; Power, Christine A.
2012-01-01
A national bovine serological survey was conducted to confirm that the prevalence of brucellosis, bluetongue, and anaplasmosis does not exceed 0.02% (95% confidence) in live cattle in Canada. Sampling consisted of a systematic random sample of 15 482 adult cattle slaughtered in federally inspected abattoirs, stratified by province. Samples were tested to detect antibodies for brucellosis, bluetongue, and anaplasmosis. All samples were negative for brucellosis. Three samples were seroreactors to bluetongue, 2 of which originated from the Okanagan Valley in British Columbia and 1 from Ontario, which after follow-up, was considered an atypical result. A total of 244 samples were seroreactors to Anaplasma and follow-up identified infection in Saskatchewan, Manitoba, and Quebec. In conclusion, the Canadian cattle population remains free of brucellosis and free of bluetongue outside the Okanagan Valley. Canada is no longer free of anaplasmosis and will be unable to claim freedom until eradication measures are completed. PMID:23450858
NASA Technical Reports Server (NTRS)
Gibson, E. K.; Mckay, D. S.; Wentworth, S. J.
1983-01-01
Weathering, diagenesis, and chemical alteration of a soil profile from the Dry Valleys of Antarctica are investigated as an analog to soil development within the Martian regolith. Soil samples from a soil pit one meter deep on Prospect Mesa, Wright Valley, are examined for their major element concentrations, water-soluble cations and anions, carbon, sulfur, and water concentrations, and related petrographic characteristics of weathering in a cold, dry environment. A petrographic study of the samples suggests that most silicate mineral and lithic fragments exhibit some degree of alteration. Chemical alteration occurs both in samples above and within the permanently frozen zone. The concentrations of water-soluble cations, for example, Na(+), K(+), Ca(2+), and anions, Cl(-), SO4(2-), NO3(-), are found to decrease significantly from the surface to the permanently frozen zone, suggesting a major movement of water-soluble species. It is also found that enrichments in secondary mineral abundances correlate with the water soluble ion concentrations. The formation of zeolites is seen throughout the soil column; these, it is thought, may be reservoirs for volatile storage within the regolith.
NASA Astrophysics Data System (ADS)
Ward, Tony J.
A yearlong sampling program for PM2.5, Semi- Volatile Organic Compounds (SVOCs), and Volatile Organic Compounds (VOCs) was conducted in 2000/2001. The data were used in a Chemical Mass Balance (CMB) Source Apportionment Model (Version 8.0) to apportion the sources of PM2.5 in the Missoula Valley. Results showed that wood combustion contributed an average of 41% to the fine fraction throughout the year. The second largest source of PM 2.5 was diesel (19%), followed by ammonium nitrate (17%), the kraft recovery boilers from Smurfit-Stone Container (14%), other hog fuel boilers (6%), and street sand (5%). Results also showed that PM2.5 levels and contributions from sources were consistent on both sides of the Missoula Valley, but VOCs were twice as high in Missoula compared to Frenchtown. Another aspect of this program was to investigate the organic fraction of the Missoula Valley PM2.5 by evaluating a modified Federal Reference Method (FRM) PM2.5 sampler. A method comparison was also made between sampling for SVOCs using the modified PM2.5 sampler and in using a Hi-volume Polyurethane Foam (PUF) sampler. Results showed that the PM 2.5 PUF measured more of the lighter SVOCs compared to the Hi-vol PUF sampler. This is most likely the result of the higher flows through the Hi-vol PUF which ``strip'' the lighter organics from the surface of the filter. The wildland fires of summer 2000 comprised one of the most severe fire seasons is U.S. history, and had a direct impact on the city of Missoula. Sampling in Missoula was already in progress when the fires began and smoke started rolling into the Missoula Valley. Samples were collected before, during, and after the 2000 fire season, and a detailed characterization of particulate and gaseous emissions from extensive wildland fires was obtained. The 2000/2001 CMB Sampling Program data collected during the 2000 fire season suggest that the main health impacts to downwind populations reside in the fine particulate exposures, with an average of 81% of the Missoula Valley PM2.5 resulting from forest fires.
Muir, K.S.; Coplen, Tyler B.
1981-01-01
Starting in 1965 the Santa Clara Valley Water District began importing about i00,000 acre-feet per year of northern California water. About one-half of this water was used to artificially recharge the Upper Penitencia Creek alluvial fan in Santa Clara Valley. In order to determine the relative amounts of local ground water and recharged imported water being pumped from the wells, stable isotopes of oxygen and hydrogen were used to trace the movement of the imported water in the alluvial fan. To trace the movement of imported water in the Upper Penitencia Creek alluvial fan, well samples were selected to give areal and depth coverage for the whole fan. The stable isotopes of oxygen-16, oxygen-18, and deuterium were measured in the water samples of imported water and from the wells and streams in the Santa Clara Valley. The d18oand dD compositions of the local runoff were about -6.00 o/oo (parts per thousand) and -40 o/oo, respectively; the average compositions for the local native ground-water samples were about -6.1 o/oo and -41 o/oo, respectively; and the average compositions of the imported water samples were -10.2 o/oo and -74 o/oo, respectively. (The oxygen isotopic composition of water samples is reported relative to Standard Mean Ocean Water, in parts per thousand.) The difference between local ground water and recharged imported water was about 4.1 o/oo in d18o and 33 o/oo in dL. The isotopic data indicate dilution of northern California water with local ground water in a downgradient direction. Two wells contain approximately 74 percent northern California water, six wells more than 50 percent. Data indicate that there may be a correlation between the percentage of northern California water and the depth or length of perforated intervals in wells.
Geochemistry of soils from the San Rafael Valley, Santa Cruz County, Arizona
Folger, Helen W.; Gray, Floyd
2013-01-01
This study was conducted to determine whether surficial geochemical methods can be used to identify subsurface mineraldeposits covered by alluvium derived from surrounding areas. The geochemical investigation focused on an anomalous geo-physical magnetic high located in the San Rafael Valley in Santa Cruz County, Arizona. The magnetic high, inferred to be asso-ciated with a buried granite intrusion, occurs beneath Quaternary alluvial and terrace deposits. Soil samples were collected at a depth of 10 to 30 centimeters below land surface along transects that traverse the inferred granite. The samples were analyzed by inductively coupled plasma-mass spectrometry and by the partial-leach Mobile Metal Ion™ method. Principal component and factor analyses showed a strong correlation between the soils and source rocks hosting base-metal replacement deposits in the Harshaw and Patagonia Mining Districts. Factor analysis also indicated areas of high metal concentrations associated with the Meadow Valley Flat. Although no definitive geochemical signature was identified for the inferred granite, concentrations otungsten and iron in the surrounding area were slightly elevated.
Application LANDSAT imagery to geologic mapping in the ice-free valleys of Antarctica
NASA Technical Reports Server (NTRS)
Houston, R. S. (Principal Investigator); Marrs, R. W.; Smithson, S. B.
1976-01-01
The author has identified the following significant results. Studies in the Ice-Free Valleys are resulted in the compilation of a sizeable library of maps and publications. Rock reflectance measurements were taken during the Antarctic summer of 1973. Spectral reflectance of rocks (mostly mafic lava flows) in the McMurdo and Ice-Free Valleys areas were measured using a filter wheel photometer equipped to measure reflectances in the four Landsat bands. A series of samples were collected at regular intervals across a large differentiated, mafic sill near Lake Vida. Chemical analyses of the sample suggest that the tonal variations in this sill are controlled by changes in the iron content of the rock. False color images were prepared for a number of areas by the diazo method and with an optical multispectral biviewer. These images were useful in defining boundaries of sea ice, snow cover, and in the study of ablating glaciers, but were not very useful for rock discrimination.
Turner, Elena A.; Kroeger, Gretchen L.; Arnold, Mariah C.; Thornton, B. Lila; Di Giulio, Richard T.; Meyer, Joel N.
2013-01-01
Mountaintop removal-valley fill coal mining has been associated with a variety of impacts on ecosystem and human health, in particular reductions in the biodiversity of receiving streams. However, effluents emerging from valley fills contain a complex mixture of chemicals including metals, metalloids, and salts, and it is not clear which of these are the most important drivers of toxicity. We found that streamwater and sediment samples collected from mine-impacted streams of the Upper Mud River in West Virginia inhibited the growth of the nematode Caenorhabditis elegans. Next, we took advantage of genetic and transgenic tools available in this model organism to test the hypotheses that the toxicity could be attributed to metals, selenium, oxidative stress, or osmotic stress. Our results indicate that in general, the toxicity of streamwater to C. elegans was attributable to osmotic stress, while the toxicity of sediments resulted mostly from metals or metalloids. PMID:24066176
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.
Wright, Michael T.; Belitz, Kenneth; Burton, Carmen A.
2005-01-01
Because of concerns over ground-water quality, the California State Water Resources Control Board (SWRCB), in collaboration with the U.S. Geological Survey and Lawrence Livermore National Laboratory, has implemented the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. A primary objective of the program is to provide a current assessment of ground-water quality in areas where public supply wells are an important source of drinking water. The San Diego GAMA study unit was the first region of the state where an assessment of ground-water quality was implemented under the GAMA program. The San Diego GAMA study unit covers the entire San Diego Drainages hydrogeologic province, and is broken down into four distinct hydrogeologic study areas: the Temecula Valley study area, the Warner Valley study area, the Alluvial Basins study area, and the Hard Rock study area. A total of 58 ground-water samples were collected from public supply wells in the San Diego GAMA study unit: 19 wells were sampled in the Temecula Valley study area, 9 in the Warner Valley study area, 17 in the Alluvial Basins study area, and 13 in the Hard Rock study area. Over 350 chemical and microbial constituents and water-quality indicators were analyzed for in this study. However, only select wells were measured for all constituents and water-quality indicators. Results of analyses were calculated as detection frequencies by constituent classification and by individual constituents for the entire San Diego GAMA study unit and for the individual study areas. Additionally, concentrations of constituents that are routinely monitored were compared to maximum contaminant levels (MCL) and secondary maximum contaminant levels (SMCL). Concentrations of constituents classified as 'unregulated chemicals for which monitoring is required' (UCMR) were compared to the 'detection level for the purposes of reporting' (DLR). Eighteen of the 88 volatile organic compounds (VOCs) and gasoline oxygenates analyzed for were detected in ground-water samples. Twenty-eight wells sampled in the San Diego GAMA study had at least a single detection of VOCs or gasoline oxygenates. These constituents were most frequently detected in the Alluvial Basin study area (11 of 17 wells), and least frequently detected in the Warner Valley study area (one of nine wells). Trihalomethanes (THMs) were the most frequently detected class of VOCs (18 of 58 wells). The most frequently detected VOCs were chloroform (18 of 58 wells), bromodichloromethane (8 of 58 wells), and methyl tert-butyl ether (MTBE) (7 of 58 wells). Three VOCs were detected at concentrations greater than their MCLs. Tetrachloroethylene (PCE) and trichloroethylene (TCE) were detected in one well in the Hard Rock study area at concentrations of 9.75 and 7.27 micrograms per liter (?g/L), respectively; the MCL for these compounds is 5 ?g/L. MTBE was detected in one well in the Alluvial Basins study area at a concentration of 28.3 ?g/L; the MCL for MTBE is 13 ?g/L. Twenty-one of the 122 pesticides and pesticide degradates analyzed for were detected in ground-water samples. Pesticide or pesticide degradates were detected in 33 of 58 wells sampled, and were most frequently detected in the Temecula Valley study area wells (9 of 14 wells), and least frequently in the Warner Valley study area wells (3 of 9 wells). Herbicides were the most frequently detected class of pesticides (31 of 58 wells), and simazine was the most frequently detected compound (27 of 58 wells), followed by deethylatrazine (14 of 58 wells), prometon (10 of 58 wells), and atrazine (9 of 58 wells). None of the pesticides detected in ground-water samples had concentrations that exceeded MCLs. Eight waste-water indicator compounds were detected in ground-water samples. Twenty-one of 47 wells sampled for waste-water indicator compounds had at least a single detection. Waste-water indicator compounds were detected most frequently in the Allu
VAN Kesteren, F; Mastin, A; Torgerson, P R; Mytynova, Bermet; Craig, P S
2017-09-01
Echinococcosis is a re-emerging zoonotic disease in Kyrgyzstan. In 2012, an echinococcosis control scheme was started that included dosing owned dogs in the Alay Valley, Kyrgyzstan with praziquantel. Control programmes require large investments of money and resources; as such it is important to evaluate how well these are meeting their targets. However, problems associated with echinococcosis control schemes include remoteness and semi-nomadic customs of affected communities, and lack of resources. These same problems apply to control scheme evaluations, and quick and easy assessment tools are highly desirable. Lot quality assurance sampling was used to assess the impact of approximately 2 years of echinococcosis control in the Alay valley. A pre-intervention coproELISA prevalence was established, and a 75% threshold for dosing compliance was set based on previous studies. Ten communities were visited in 2013 and 2014, with 18-21 dogs sampled per community, and questionnaires administered to dog owners. After 21 months of control efforts, 8/10 communities showed evidence of reaching the 75% praziquantel dosing target, although only 3/10 showed evidence of a reduction in coproELISA prevalence. This is understandable, since years of sustained control are required to effectively control echinococcosis, and efforts in the Alay valley should be and are being continued.
ERIC Educational Resources Information Center
Johns Hopkins Univ., Baltimore, MD. Center for Research in Scientific Communication.
The April 1967 Annual Meeting of the American Geophysical Union was the subject of an investigation of scientific information exchange among geophysicists. The study focused on meeting presentation papers and drew a sample of 240 of the 800 presentation authors. The results of the meeting study demonstrated the currency of the work reported by…
Rouse, William A.; Houseknecht, David W.
2012-01-01
The Cook Inlet-Susitna region of south-central Alaska contains large quantities of gas-bearing coal of Tertiary age. The U.S. Geological Survey in 2011 completed an assessment of undiscovered, technically recoverable coal-bed gas resources underlying the Cook Inlet-Susitna region based on the total petroleum system (TPS) concept. The Cook Inlet Coal-Bed Gas TPS covers about 9,600,000 acres and comprises the Cook Inlet basin, Matanuska Valley, and Susitna lowland. The TPS contains one assessment unit (AU) that was evaluated for coal-bed gas resources between 1,000 and 6,000 feet in depth over an area of about 8,500,000 acres. Coal beds, which serve as both the source and reservoir for natural gas in the AU, were deposited during Paleocene-Pliocene time in mires associated with a large trunk-tributary fluvial system. Thickness of individual coal beds ranges from a few inches to more than 50 feet, with cumulative coal thickness of more than 800 feet in the western part of the basin. Coal rank ranges from lignite to subbituminous, with vitrinite reflectance values less than 0.6 percent throughout much of the AU. The AU is considered hypothetical because only a few wells in the Matanuska Valley have tested the coal-bed reservoirs, so the use of analog coal-bed gas production data was necessary for this assessment. In order to estimate reserves that might be added in the next 30 years, coal beds of the Upper Fort Union Formation in the Powder River Basin of Wyoming and Montana were selected as the production analog for Tertiary coal beds in the Cook Inlet-Susitna region. Upper Fort Union coal beds have similar rank (lignite to subbituminous), range of thickness, and coal-quality characteristics as coal beds of the Tertiary Kenai Group. By use of this analog, the mean total estimate of undiscovered coal-bed gas in the Tertiary Coal-Bed Gas AU is 4.674 trillion cubic feet (TCF) of gas.
Observation of macroscopic valley-polarized monolayer exciton-polaritons at room temperature
NASA Astrophysics Data System (ADS)
Lundt, N.; Stoll, S.; Nagler, P.; Nalitov, A.; Klembt, S.; Betzold, S.; Goddard, J.; Frieling, E.; Kavokin, A. V.; Schüller, C.; Korn, T.; Höfling, S.; Schneider, C.
2017-12-01
In this Rapid Communication, we address the chiral properties of valley exciton-polaritons in a monolayer of W S2 in the regime of strong light-matter coupling with a Tamm-plasmon resonance. We observe that the effect of valley polarization, which manifests in the circular polarization of the emitted photoluminescence as the sample is driven by a circularly polarized laser, is strongly enhanced in comparison to bare W S2 monolayers and can even be observed under strongly nonresonant excitation at ambient conditions. In order to explain this effect in more detail, we study the relaxation and decay dynamics of exciton-polaritons in our device, elaborate the role of the dark state, and present a microscopic model to explain the wave-vector-dependent valley depolarization by the linear polarization splitting inherent to the microcavity. We believe that our findings are crucial for designing novel polariton-valleytronic devices which can be operated at room temperature.
Epps, Clinton W.; Wehausen, John D.; Sloan, William B.; Holt, Stacy; Creech, Tyler G.; Crowhurst, Rachel S.; Jaeger, Jef R.; Longshore, Kathleen M.; Monello, Ryan J.
2013-01-01
Where possible, we revisited many of the water sources and other locations originally investigated by Welles and Welles (1961) and earlier researchers. We extracted DNA from fecal pellets, carcass tissue samples, and blood samples archived from earlier captures and genotyped them using highly variable genetic markers (15 microsatellite loci) with sufficient power to distinguish individuals and characterize gene flow and genetic structure. We also analyzed DNA samples collected from other bighorn sheep populations extending north to the White Mountains, west to the Inyo Mountains, south to the Avawatz Mountains, and southeast to the Clark Mountain Range, Kingston Range, and Spring Mountains of Nevada. We estimated genetic structure and recent gene flow among nearly all known populations of bighorn sheep in and around Death Valley National Park (DEVA), and used assignment tests to evaluate individual and population-level genetic structure to infer connectivity across the region. We found that bighorn sheep are still widely distributed in mountain ranges throughout DEVA, including many of the areas described by Welles and Welles (1961), although some use patterns appear to have changed and other areas still require resurvey. Gene flow was relatively high through some sections of fairly continuous habitat, such as the Grapevine and Funeral Mountains along the eastern side of Death Valley, but other populations were more isolated. Genetic diversity was relatively high throughout the park. Although southern Death Valley populations were genetically distinct from populations to the southeast, population assignment tests and recent gene flow estimates suggested that individuals occasionally migrate between those regions, indicating the potential for the recent outbreak of respiratory disease in the southern Mojave Desert to spread into the Death Valley system. We recommend careful monitoring of bighorn sheep using remote cameras to check for signs of respiratory disease in southeastern DEVA and ground surveys in the still-understudied southwestern part of DEVA.
2013-01-01
Background Deer tick virus, DTV, is a genetically and ecologically distinct lineage of Powassan virus (POWV) also known as lineage II POWV. Human incidence of POW encephalitis has increased in the last 15 years potentially due to the emergence of DTV, particularly in the Hudson Valley of New York State. We initiated an extensive sampling campaign to determine whether POWV was extant throughout the Hudson Valley in tick vectors and/or vertebrate hosts. Methods More than 13,000 ticks were collected from hosts or vegetation and tested for the presence of DTV using molecular and virus isolation techniques. Vertebrate hosts of Ixodes scapularis (black-legged tick) were trapped (mammals) or netted (birds) and blood samples analyzed for the presence of neutralizing antibodies to POWV. Maximum likelihood estimates (MLE) were calculated to determine infection rates in ticks at each study site. Results Evidence of DTV was identified each year from 2007 to 2012, in nymphal and adult I. scapularis collected from the Hudson Valley. 58 tick pools were positive for virus and/or RNA. Infection rates were higher in adult ticks collected from areas east of the Hudson River. MLE limits ranged from 0.2-6.0 infected adults per 100 at sites where DTV was detected. Virginia opossums, striped skunks and raccoons were the source of infected nymphal ticks collected as replete larvae. Serologic evidence of POWV infection was detected in woodchucks (4/6), an opossum (1/6), and birds (4/727). Lineage I, prototype POWV, was not detected. Conclusions These data demonstrate widespread enzootic transmission of DTV throughout the Hudson Valley, in particular areas east of the river. High infection rates were detected in counties where recent POW encephalitis cases have been identified, supporting the hypothesis that lineage II POWV, DTV, is responsible for these human infections. PMID:24016533
Dupuis, Alan P; Peters, Ryan J; Prusinski, Melissa A; Falco, Richard C; Ostfeld, Richard S; Kramer, Laura D
2013-07-15
Deer tick virus, DTV, is a genetically and ecologically distinct lineage of Powassan virus (POWV) also known as lineage II POWV. Human incidence of POW encephalitis has increased in the last 15 years potentially due to the emergence of DTV, particularly in the Hudson Valley of New York State. We initiated an extensive sampling campaign to determine whether POWV was extant throughout the Hudson Valley in tick vectors and/or vertebrate hosts. More than 13,000 ticks were collected from hosts or vegetation and tested for the presence of DTV using molecular and virus isolation techniques. Vertebrate hosts of Ixodes scapularis (black-legged tick) were trapped (mammals) or netted (birds) and blood samples analyzed for the presence of neutralizing antibodies to POWV. Maximum likelihood estimates (MLE) were calculated to determine infection rates in ticks at each study site. Evidence of DTV was identified each year from 2007 to 2012, in nymphal and adult I. scapularis collected from the Hudson Valley. 58 tick pools were positive for virus and/or RNA. Infection rates were higher in adult ticks collected from areas east of the Hudson River. MLE limits ranged from 0.2-6.0 infected adults per 100 at sites where DTV was detected. Virginia opossums, striped skunks and raccoons were the source of infected nymphal ticks collected as replete larvae. Serologic evidence of POWV infection was detected in woodchucks (4/6), an opossum (1/6), and birds (4/727). Lineage I, prototype POWV, was not detected. These data demonstrate widespread enzootic transmission of DTV throughout the Hudson Valley, in particular areas east of the river. High infection rates were detected in counties where recent POW encephalitis cases have been identified, supporting the hypothesis that lineage II POWV, DTV, is responsible for these human infections.
Moraga, Mauricio; Santoro, Calogero M; Standen, Vivien G; Carvallo, Pilar; Rothhammer, Francisco
2005-06-01
Archeological evidence suggests that the iconographic and technological developments that took place in the highlands around Lake Titicaca in the Central Andean region had an influence on the cultural elaborations of the human groups in the valleys and the Pacific coast of northern Chile. In a previous communication, we were able to show, by means of a distance analysis, that a craniofacial differentiation accompanied the process of cultural evolution in the valleys (Rothhammer and Santoro [2001] Lat. Am. Antiq. 12:59-66). Recently, numerous South Amerindian mtDNA studies were published, and more accurate molecular techniques to study ancient mtDNA are available. In view of these recent developments, we decided 1) to study chronological changes of ancient mtDNA haplogroup frequencies in the nearby Lluta, Azapa, and Camarones Valleys, 2) to identify microevolutionary forces responsible for such changes, and 3) to compare ancient mtDNA haplogroup frequencies with previous data in order to validate craniometrical results and to reconstruct the biological history of the prehistoric valley groups in the context of their interaction with culturally more developed highland populations. From a total of 97 samples from 83 individuals, 68 samples (61 individuals) yielded amplifications for the fragments that harbor classical mtDNA markers. The haplogroup distribution among the total sample was as follows: 26.2%, haplogroup A; 34.4%, haplogroup B; 14.8%, haplogroup C; 3.3%, haplogroup D; and 21.3%, other haplogroups. Haplogroup B tended to increase, and haplogroup A to decrease during a 3,900-year time interval. The sequence data are congruent with the haplogroup analysis. In fact, the sequencing of hypervariable region I of 30 prehistoric individuals revealed 43 polymorphic sites. Sequence alignment and subsequent phylogenetic tree construction showed two major clusters associated with the most common restriction haplogroups. Individuals belonging to haplogroups C and D tended to cluster together with nonclassical lineages. 2004 Wiley-Liss, Inc.
Study of air pollution in the Aburra Valley, Colombia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bedoya, J.; Bedoya, E.
1980-01-01
A study of air pollution in the Aburra Valley, Colombia, showed that in 1978, the total vehicular (automobiles, buses, and trucks) fuel consumption, including gasoline, fuel oil, kerosine and aviation gasoline, was 136 million gal, which, based on EPA emission factors, produced 755 metric tons of particulate matter and 245 metric tons of sulfur dioxide. In the city of Medellin, during 1976-1979, sulfur dioxide concentrations averaged 40 jg/cu m annually at two sampling stations representing the worst cases, a value below the Colombian standard of 70 jg/cu m. The annual average for the city showed an increase of 22 jg/cumore » m in 1977 to 30 jg/cu m in 1979. In March 1978, the Olaya Herrera Airport in Aburra Valley was closed a number of hours due to lack of visibility caused by fumes; on 3/17/78, it was closed ten hours. The economic and demographic aspects of the Aburra Valley, industrial sources of pollution in the Valley and Colombian air pollution regulations are discussed.« less
Extracting valley-ridge lines from point-cloud-based 3D fingerprint models.
Pang, Xufang; Song, Zhan; Xie, Wuyuan
2013-01-01
3D fingerprinting is an emerging technology with the distinct advantage of touchless operation. More important, 3D fingerprint models contain more biometric information than traditional 2D fingerprint images. However, current approaches to fingerprint feature detection usually must transform the 3D models to a 2D space through unwrapping or other methods, which might introduce distortions. A new approach directly extracts valley-ridge features from point-cloud-based 3D fingerprint models. It first applies the moving least-squares method to fit a local paraboloid surface and represent the local point cloud area. It then computes the local surface's curvatures and curvature tensors to facilitate detection of the potential valley and ridge points. The approach projects those points to the most likely valley-ridge lines, using statistical means such as covariance analysis and cross correlation. To finally extract the valley-ridge lines, it grows the polylines that approximate the projected feature points and removes the perturbations between the sampled points. Experiments with different 3D fingerprint models demonstrate this approach's feasibility and performance.
Ground-water resources investigation in the Amran Valley, Yeman Arab Republic
Tibbitts, G. Chase; Aubel, James
1980-01-01
A program of hydrologic studies and exploratory drilling was conducted intermittently between 1974 and 1978 to evaluate the water-bearing properties of the unconsolidated alluvial sediments and associated rocks in the semi-arid Amran Valley basin, an 800-square-kilometer area in north-central Yemen Arab Republic. Inventory data from 395 wells were compiled, observation well and rain-gage networks were established and 16 standard complete chemical analyses were made for samples from selected wells. The water resources of the area were overexploited. The chemical quality of the water is generally good. Four aquifer tests were run to determine transmissivity and storage characteristics. The pumping tests show that groundwater occurs under semi-confined leaky-aquifer conditions in the valley fill. Wells drilled in the alluvial fill of the south-central part of the valley have the highest yields. Wells penetrating the limestone and volcanic rocks generally have little or no yield except in fracture zones. Basalt flows occur interbedded with the wadi alluvium at several depths. Cropping out rocks in the Amran Valley range in age from late Jurassic to Holocene. (USGS)
Effects of winery wastewater on soil, grape nutrition, and wine quality
USDA-ARS?s Scientific Manuscript database
Many wineries are interested in recycling wastewater for irrigation. This project investigates the effects on winemaking when winery wastewater (WW) is recycledfor irrigation. Water samples and soils samples were collected from one Napa Valley and one Sonoma vineyard. Leaf and berry samples were col...
Aquatic invertebrate ecology during a simulated botulism epizootic in a Sacramento Valley wetland
Hicks, Jane M.; Euliss, Ned H.; Harris, Stanley W.
1997-01-01
We investigated the effect of decomposing duck carcasses on aquatic invertebrate numbers, biomass, and taxonomic composition in a seasonally flooded, impounded wetland in the Sacramento Valley, California during August–November 1988 and 1989. Major invertebrate taxa were copepods (Cyclopoida, occurred in 8.3% of samples), water fleas (Daphnidae, 8.9%), water boatmen (Corisella, 10.4%), and midge larvae (Goeldichironomus, 9.3%;Chironomus, 11.5%;Tanypus, 17.2%). We found no treatment (carcass present or no carcass) by sampling day interaction for these taxa. We found a significant difference between sample plots with carcasses and those without carcasses only for Daphnidae counts andCorisella wet weights. We found significant differences among sampling days for these taxa that were probably statistical artifacts. We were unable to detect any effect of duck carcasses on aquatic invertebrate community structure and the potential availability of invertebrates as waterfowl food.
Setmire, J.G.; Schroeder, R.A.; Densmore, J.N.; Goodbred, S.O.; Audet, D.J.; Radke, W.R.
1993-01-01
Results of a detailed study by the National Irrigation Water-Quality Program (NIWQP), U.S. Department of the Interior, indicate that factors controlling contaminant concentrations in subsurface irrigation drainwater in the Imperial Valley are soil characteristics, hydrology, and agricultural practices. Higher contaminant concentrations commonly were associated with clayey soils, which retard the movement of irrigation water and thus increase the degree of evaporative concentration. Regression of hydrogen- and oxygen-isotope ratios in samples collected from sumps yields a linear drainwater evaporation line that extrapolates through the isotopic composition of Colorado River water, thus demonstrating that Colorado River water is the sole source of subsurface drainwater in the Imperial Valley. Ratios of selenium to chloride indicate that selenium present in subsurface drainwater throughout the Imperial Valley originates from the Colorado River. The selenium load discharged to the Salton Sea from the Alamo River, the largest contributor, is about 6.5 tons/yr. Biological sampling and analysis showed that drainwater contaminants, including selenium, boron, and DDE, are accumulating in tissues of migratory and resident birds that use food sources in the Imperial Valley and the Salton Sea. Selenium concentration in fish-eating birds, shorebirds, and the endangered Yuma clapper rail were at levels that could affect reproduction. Boron concentrations in migratory waterfowl and resident shorebirds were at levels that potentially could cause reduced growth in young. As a result of DDE contamination of food sources, waterfowl and fish-eating birds in the Imperial Valley may be experiencing reproductive impairment.
NASA Astrophysics Data System (ADS)
Tremblay, Marissa; Spagnolo, Matteo; Ribolini, Adriano; Shuster, David
2016-04-01
The Gesso Valley, located in the southwestern-most, Maritime portion of the European Alps, contains an exceptionally well-preserved record of glacial advances during the late Pleistocene and Holocene. Detailed geomorphic mapping, geochronology of glacial deposits, and glacier reconstructions indicate that glaciers in this Mediterranean region responded to millennial scale climate variability differently than glaciers in the interior of the European Alps. This suggests that the Mediterranean Sea somehow modulated the climate of this region. However, since glaciers respond to changes in temperature and precipitation, both variables were potentially influenced by proximity to the Sea. To disentangle the competing effects of temperature and precipitation changes on glacier size, we are constraining past temperature variations in the Gesso Valley since the Last Glacial Maximum (LGM) using cosmogenic noble gas paleothermometry. The cosmogenic noble gases 3He and 21Ne experience diffusive loss from common minerals like quartz and feldspars at Earth surface temperatures. Cosmogenic noble gas paleothermometry utilizes this open-system behavior to quantitatively constrain thermal histories of rocks during exposure to cosmic ray particles at the Earth's surface. We will present measurements of cosmogenic 3He in quartz sampled from moraines in the Gesso Valley with LGM, Bühl stadial, and Younger Dryas ages. With these 3He measurements and experimental data quantifying the diffusion kinetics of 3He in quartz, we will provide a preliminary temperature reconstruction for the Gesso Valley since the LGM. Future work on samples from younger moraines in the valley system will be used to fill in details of the more recent temperature history.
Dadáková, Eva; Brožová, Kristýna; Piel, Alex K; Stewart, Fiona A; Modrý, David; Celer, Vladimír; Hrazdilová, Kristýna
2018-01-01
Adenoviruses are a widespread cause of diverse human infections with recently confirmed zoonotic roots in African great apes. We focused on savanna-dwelling chimpanzees in the Issa Valley (Tanzania), which differ from those from forested sites in many aspects of behavior and ecology. PCR targeting the DNA polymerase gene detected AdV in 36.7% (69/188) of fecal samples. We detected five groups of strains belonging to the species Human mastadenovirus E and two distinct groups within the species Human mastadenovirus C based on partial hexon sequence. All detected AdVs from the Issa Valley are related to those from nearby Mahale and Gombe National Parks, suggesting chimpanzee movements and pathogen transmission.
Keeter, Gail L.
1980-01-01
The study area of this report includes the eastern valley area of Contra Costa County and all of San Joaquin County, an area of approximately 1,600 square miles in the northern part of the San Joaquin Valley, Calif. Between December 1977 and December 1978, 1,489 wells were selectively canvassed. During May and June in 1978 and 1979, water samples were collected for chemical analysis from 321 of these wells. Field determinations of alkalinity, conductance, pH, and temperature were made, and individual constituents were analyzed. This report is the fourth in a series of baseline data reports on wells in the Sacramento and San Joaquin Valleys. (USGS)
Geohydrology and water-chemistry of the Alexander Valley, Sonoma County, California
Metzger, Loren F.; Farrar, Christopher D.; Koczot, Kathryn M.; Reichard, Eric G.
2006-01-01
This study of the geohydrology and water chemistry of the Alexander Valley, California, was done to provide an improved scientific basis for addressing emerging water-management issues, including potential increases in water demand and changes in flows in the Russian River. The study tasks included (1) evaluation of existing geohydrological, geophysical, and geochemical data; (2) collection and analysis of new geohydrologic data, including subsurface lithologic data, ground-water levels, and streamflow records; and (3) collection and analysis of new water-chemistry data. The estimated total water use for the Alexander Valley for 1999 was approximately 15,800 acre-feet. About 13,500 acre-feet of this amount was for agricultural use, primarily vineyards, and about 2,300 acre-feet was for municipal/industrial use. Ground water is the main source of water supply for this area. The main sources of ground water in the Alexander Valley are the Quaternary alluvial deposits, the Glen Ellen Formation, and the Sonoma Volcanics. The alluvial units, where sufficiently thick and saturated, comprise the best aquifer in the study area. Average recharge to the Alexander Valley is estimated from a simple, basinwide water budget. On the basis of an estimated annual average of 298,000 acre-feet of precipitation, 160,000 acre-feet of runoff, and 113,000 to 133,000 acre-feet of evapotranspiration, about 5,000 to 25,000 acre-feet per year is available for ground-water recharge. Because this estimate is based on differences between large numbers, there is significant uncertainty in this recharge estimate. Long-term changes in ground-water levels are evident in parts of the study area, but because of the sparse network and lack of data on well construction and lithology, it is uncertain if any significant changes have occurred in the northern part of the study area since 1980. In the southern half of the study area, ground-water levels generally were lower at the end of the 2002 irrigation season than at the end of the 1980 season, which suggests that a greater amount of ground water is being pumped in the southern half of the study area in recent years compared with that pumped in the early 1980s. Water-chemistry data for samples collected from 11 wells during 2002-04 indicate that water quality in the study area generally is acceptable for potable use. Two wells, however, each contained one constituent (241 ?g/L of manganese and 1,350 ?g/L of boron) in excess of the recommended standards for drinking water (50 ?g/L and 1,000 ?g/L, respectively). The chemical composition of water from most of the wells sampled for major ions plot as a mixed cation-bicarbonate, magnesium-bicarbonate, or calcium-bicarbonate type water. The ionic composition of the historical and recent samples from wells in the Alexander Valley is similar to that of the historical surface-water samples collected from the Russian River near Healdsburg. This suggests a similar source of water, particularly for wells that are less than 200 feet total depth and perforated in Quaternary alluvial deposits. Water from deeper, non-alluvial wells may contain slightly higher concentrations of sodium as a result of cation exchange. Water samples collected from several wells over an approximately 30-year period suggest a progressive change in water chemistry over time. Samples from the southern part of the valley show a trend towards higher ionic concentrations and increasing concentrations of particular constituents such as sulfate.
Near-road sampling of PM2. 5, BC, and fine-particle chemical components in Kathmandu Valley, Nepal
NASA Astrophysics Data System (ADS)
Shakya, Kabindra M.; Rupakheti, Maheswar; Shahi, Anima; Maskey, Rejina; Pradhan, Bidya; Panday, Arnico; Puppala, Siva P.; Lawrence, Mark; Peltier, Richard E.
2017-06-01
Semicontinuous PM2. 5 and black carbon (BC) concentrations, and 24 h integrated PM2. 5 filter samples were collected near roadways in the Kathmandu Valley, Nepal. Instruments were carried by a group of volunteer traffic police officers in the vicinity of six major roadway intersections in the Kathmandu Valley across two sampling periods in 2014. Daily PM2. 5 filter samples were analyzed for water-soluble inorganic ions, elemental carbon (EC) and organic carbon (OC), and 24 elements. Mean PM2. 5 and BC concentrations were 124.76 µg m-3 and 16.74 µgC m-3 during the drier spring sampling period, and 45.92 µg m-3 and 13.46 µgC m-3 during monsoonal sampling. Despite the lower monsoonal PM2. 5 concentrations, BC and several elements were not significantly lower during the monsoon, which indicates an important contribution of vehicle-related emissions throughout both seasons in this region. During the monsoon, there was an enhanced contribution of chemical species (elements and water-soluble inorganic ions), except secondary inorganic ions, and BC to PM2. 5 (crustal elements: 19 %; heavy metals: 5 %; and BC: 39 %) compared to those in spring (crustal elements: 9 %; heavy metals: 1 %; and BC: 18 %). Silica, calcium, aluminum, and iron were the most abundant elements during both spring and the monsoon, with total concentrations of 12.13 and 8.85 µg m-3, respectively. PM2. 5 and BC showed less spatial variation compared to that for individual chemical species.
NASA Astrophysics Data System (ADS)
Shakya, K. M.; Rupakheti, M.; Peltier, R.
2016-12-01
Kathmandu valley located in the foothills of Himalaya in Nepal suffers from serious air pollution problems. Near-roadway PM2.5 and BC were measured at six sites in the Kathmandu valley using a portable scattering nephelometer (pDR-1500, Thermo Inc., US) and a microaethalometer (Aeth Labs, US), respectively. 37 mm polytetrafluoroethylene filter samples were analyzed by a laboratory-based X-ray fluorescence (XRF) spectrometer (QUANT'X, Thermo Inc., US) for elements, with subsequent filter extraction in deionized water followed by ion chromatography (ICS-1100, Thermo Inc., US) for water-soluble ions. PM2.5 concentrations at six different locations in the Kathmandu Valley, Nepal showed distinct seasonal variability. There was a reduction of 57-74% in PM2.5 levels during the monsoonal period (July 20 - August 22, 2014) compared to the drier winter season (February 16 - April 4, 2014). Daily means of PM2.5 were 124.76 and 45.92 μg/m3 during winter and monsoon, respectively. BC concentrations, however, were marginally reduced during the monsoon (13.46 μgC/m3) compared to that in winter (16.74 μgC/m3). Four sites located along a busy commercial ring road had higher PM2.5 levels than the two sites located inside the ring road. Chemical analysis of 24 hour PM2.5 filter samples shows dust and traffic sources as the most important PM emission source at these locations. Silica, calcium, aluminum, and iron were the most abundant elements during both winter and monsoon, with the total concentrations of 12.13 and 8.85 μg/m3, respectively. Coefficient of divergence calculated from the four main sites resulted in more heterogeneity for chemical species compared to PM2.5 and BC. This suggests though PM2.5 and BC levels might be similar in the valley, their emission sources and production might differ across the valley. Our findings provide important insights on physical and chemical characteristics of particulate matter and its sources, which will be useful in designing appropriate mitigation measures, which the valley desperately needs.
Sylvester, Marc A.; Brown, William M.
1978-01-01
Two basins (Castro Valley Creek, in Alameda County, and Strong Ranch Slough, in Sacramento County) in the San Francisco Bay and Sacramento-San Joaquin Delta region (Bay-Delta region) were sampled intensively (3-15 minute intervals) during three storms between October 1974 and April 1975. Both basins are primarily residential, but the Strong Ranch Slough basin is almost entirely urbanized and nearly flat, while the Castro Valley Creek basin possesses some rural areas and slopes greater than 70 percent in the headwaters. Water discharge and concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, nitrite and nitrate, total Kjeldahl nitrogen, total orthophosphorus, and settleable matter were usually greater at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Concentrations of these constituents and water discharge changed more rapidly at the Castro Valley Creek basin than at the Strong Ranch Slough basin. Of the four subbasins sampled (two in each basin), constituent concentrations in runoff from a residential subbasin were usually greatest. Quantity and quality of runoff were related to environmental characteristics such as slope, perviousness, residential development and maintenance, and channel conditions. Greater water discharge and concentrations of constituents in the Castro Valley Creek basin seem to be partly due to steeper slopes, less perviousness, and smaller residential lot sizes than are in the Strong Ranch Slough basin. Erosion of steep slopes disturbed by grazing and residential development, poorly maintained dwellings and lots, and a mostly earthen drainage channel in the Castro Valley Creek basin are probably responsible for the greater concentrations of suspended solids and settleable matter in runoff from this basin. In both basins, the highest observed concentrations of suspended solids, chemical oxygen demand, 5-day biochemical oxygen demand, settleable matter, total Kjeldahl nitrogen, and total orthophosphorus were observed at or near peak water discharges. Flow-weighted and arithmetic-mean concentrations of suspended solids in Castro Valley Creek exceed the arithmetic-mean concentration of suspended solids in medium-strength untreated sewage. These results indicate that control of urban storm runoff in the Bay-Delta region may be desirable to protect receiving water.
NASA Astrophysics Data System (ADS)
Zhang, Wei; Harbor, Jon; Cui, Zhijiu; Liu, Liang; Liu, Beibei; Fu, Yanjing; Shi, Yuanhuang; Gribenski, Natacha; Blomdin, Robin; Stroeven, Arjen; Caffee, Marc; Jansson, Krister
2014-05-01
Reconstructions of the timing and extent of past glaciation provide key constraints for paleoclimate and numerical modeling of past glacier behavior. As part of the multinational Central Asian Paleoglaciology Project we are reconstructing the timing and extent of past glaciation along and across a series of mountain ranges in central Asia using consistent methods for mapping, field investigations and numerical dating. Here we report on new findings for the Kanas Valley in northwest China, a large glaciated valley system on the south side of the Altai Mountains. Previous studies have concluded that the Kanas Valley has been shaped by a series of major glacial advances that produced overdeepened basins, a U-shaped valley cross profile, and extensive glacial and glaciofluvial deposits. Existing Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) dating results suggest major glaciation in the Kanas Valley during Marine Oxygen Isotope Stages (MIS) 3, 5, and 6, but very limited MIS 2 glaciation. Limited MIS 2 glaciation has also been suggested for other parts of central Asia, and this contrasts with extensive MIS 2 glaciation in Europe and North America. Field studies in 2013 provided new evidence for the highest elevation extent of glaciation in the Kanas Valley in the vicinity of the 20-km long Lake Kanas, with the upper limit of distinct erratics on the valley sidewalls indicating past ice thicknesses here up to 1000 m. Upper limits of erratics extending from Lake Kanas to the mapped maximum down-valley extent of glaciation suggest an ice surface slope of 1.8 degrees for the lower half of the paleoglacier in the Kanas Valley, assuming that all the erratics were deposited at the same time. Systematic sampling of glacial erratics, basal till, terminal moraines, glacially eroded bedrock, and glaciofluvial deposits provided material that is being used for cosmogenic radionuclide, OSL and ESR dating of the glacial chronology, and for dating intercomparisons.
Winston Paul Smith; Daniel J. Twedt; David A. Wiedenfeld; Paul B. Hamel; Robert P. Ford; Robert J. Cooper
1993-01-01
To compare efficacy of point count sampling in bottomland hardwood forests, duration of point count, number of point counts, number of visits to each point during a breeding season, and minimum sample size are examined.
Tanaka, Yasuhiro; Nishida, Kei; Nakamura, Takashi; Chapagain, Saroj Kumar; Inoue, Daisuke; Sei, Kazunari; Mori, Kazuhiro; Sakamoto, Yasushi; Kazama, Futaba
2012-03-01
Although groundwater is a major water supply source in the Kathmandu Valley of Nepal, it is known that the groundwater has significant microbial contamination exceeding the drinking water quality standard recommended by the World Health Organization (WHO), and that this has been implicated in causing a variety of diseases among people living in the valley. However, little is known about the distribution of pathogenic microbes in the groundwater. Here, we analysed the microbial communities of the six water samples from deep tube wells by using the 16S rRNA gene sequences based culture-independent method. The analysis showed that the groundwater has been contaminated with various types of opportunistic microbes in addition to fecal microbes. Particularly, the clonal sequences related to the opportunistic microbes within the genus Acinetobacter were detected in all samples. As many strains of Acinetobacter are known as multi-drug resistant microbes that are currently spreading in the world, we conducted a molecular-based survey for detection of the gene encoding carbapenem-hydrolysing β-lactamase (bla(oxa-23-like) gene), which is a key enzyme responsible for multi-drug resistance, in the groundwater samples. Nested polymerase chain reaction (PCR) using two specific primer sets for amplifying bla(oxa-23-like) gene indicated that two of six groundwater samples contain multi-drug resistant Acinetobacter.
Silva-Pinto, Verónica; Arriaza, Bernardo; Standen, Vivien
2010-04-01
The Camarones River Valley, located in the extreme north of Chile, is characterized by high environmental arsenic levels and an arid desert. It has been inhabited by humans for the past 7,000 years. Evidence exists for chronic arsenic poisoning in both prehispanic and present populations residing in the area. Chronic arsenic exposure causes multi-systemic problems and can induce congenital malformations, in particular neural tube development defects such as spina bifida. To study the prevalence of spina bifida among prehispanic mummies of the area. One hundred and twenty prehistoric adult individuals were analyzed for evidence of spina bifda occulta of the sacrum in skeletal samples from the sites of Camarones 8, Camarones 9, Azapa 140 and Lluta 54, held in repository at the Museo Universidad de Tarapacá de Arica- San Miguel de Azapa. A diagnosis was considered positive when at least S1, S2 or S3 were affected. As controls, mummies of individuals that resided in Lluta and Azapa valley, with a low arsenic exposure, were analyzed. The frequency of spina bifida occulta among samples from the Camarones coast and Lluta and Azapa Valley were 13.5 and 2.4% respectively. Considering these were contemporaneous samples, and are believed to have had no other differences in diet or other factors, the differential exposures to arsenic could have produced the observed differences in spina bifida frequencies.
Hopkins, Candice B.; Bartolino, James R.
2013-01-01
Residents and resource managers of the Wood River Valley of south-central Idaho are concerned about the effects that population growth might have on the quality of groundwater and surface water. As part of a multi-phase assessment of the groundwater resources in the study area, the U.S. Geological Survey evaluated the quality of water at 45 groundwater and 5 surface-water sites throughout the Wood River Valley during July and August 2012. Water samples were analyzed for field parameters (temperature, pH, specific conductance, dissolved oxygen, and alkalinity), major ions, boron, iron, manganese, nutrients, and Escherichia coli (E.coli) and total coliform bacteria. This study was conducted to determine baseline water quality throughout the Wood River Valley, with special emphasis on nutrient concentrations. Water quality in most samples collected did not exceed U.S. Environmental Protection Agency standards for drinking water. E. coli bacteria, used as indicators of water quality, were detected in all five surface-water samples and in two groundwater samples collected. Some analytes have aesthetic-based recommended drinking water standards; one groundwater sample exceeded recommended iron concentrations. Nitrate plus nitrite concentrations varied, but tended to be higher near population centers and in agricultural areas than in tributaries and less populated areas. These higher nitrate plus nitrite concentrations were not correlated with boron concentrations or the presence of bacteria, common indicators of sources of nutrients to water. None of the samples collected exceeded drinking-water standards for nitrate or nitrite. The concentration of total dissolved solids varied considerably in the waters sampled; however a calcium-magnesium-bicarbonate water type was dominant (43 out of 50 samples) in both the groundwater and surface water. Three constituents that may be influenced by anthropogenic activity (chloride, boron, and nitrate plus nitrite) deviate from this pattern and show a wide distribution of concentrations in the unconfined aquifer, indicating possible anthropogenic influence. Time-series plots of historical water-quality data indicated that nitrate does not seem to be increasing or decreasing in groundwater over time; however, time-series plots of chloride concentrations indicate that chloride may be increasing in some wells. The small amount of temporal variability in nitrate concentrations indicates a lack of major temporal changes to groundwater inputs.
Henaux, V.; Samuel, M.D.; Dusek, Robert J.; Fleskes, J.P.; Ip, Hon S.
2012-01-01
Although wild waterfowl are the main reservoir for low pathogenic avian influenza viruses (LPAIv), the environment plays a critical role for the circulation and persistence of AIv. LPAIv may persist for extended periods in cold environments, suggesting that waterfowl breeding areas in the northern hemisphere may be an important reservoir for AIv in contrast to the warmer southern wintering areas. We evaluated whether southern wetlands, with relatively small populations (thousands) of resident waterfowl, maintain AIv in the summer, prior to the arrival of millions of migratory birds. We collected water and fecal samples at ten wetlands in two regions (Yolo Bypass and Sacramento Valley) of the California Central Valley during three bi-weekly intervals beginning in late July, 2010. We detected AIv in 29/367 fecal samples (7.9%) and 12/597 water samples (2.0%) by matrix real time Reverse Transcription Polymerase Chain Reaction (rRT-PCR). We isolated two H3N8, two H2N3, and one H4N8 among rRT-PCR positive fecal samples but no live virus from water samples. Detection of AIv RNA in fecal samples was higher from wetlands in the Sacramento Valley (11.9%) than in the Yolo Bypass (0.0%), but no difference was found for water samples (2.7 vs. 1.7%, respectively). Our study showed that low densities of hosts and unfavorable environmental conditions did not prevent LPAIv circulation during summer in California wetlands. Our findings justify further investigations to understand AIv dynamics in resident waterfowl populations, compare AIv subtypes between migratory and resident waterfowl, and assess the importance of local AIv as a source of infection for migratory birds.
Molecular detection of Rift Valley fever virus in serum samples from selected areas of Tanzania.
Chengula, Augustino Alfred; Kasanga, Christopher Jacob; Mdegela, Robinson Hammerthon; Sallu, Raphael; Yongolo, Mmeta
2014-04-01
Rift Valley fever (RVF) is an acute mosquito-borne viral zoonotic disease affecting domestic animals and humans caused by the Rift Valley fever virus (RVFV). The virus belongs to the genus Phlebovirus of the family Bunyaviridae. The main aim of this study was to detect the presence of antibodies to RVFV as well as the virus in the serum samples that were collected from livestock during the 2006/2007 RVF outbreaks in different locations in Tanzania. Analysis of selected samples was done using a RVF-specific inhibition enzyme-linked immunosorbent assay (I-ELISA) and reverse transcription polymerase chain reaction (RT-PCR). Genomic viral RNA was extracted directly from serum samples using a QIAamp Viral RNA Mini Kit (QIAGEN), and a one-step RT-PCR protocol was used to amplify the S segment of RVFV. Positive results were obtained in 39.5% (n = 200) samples using the RVF I-ELISA, and 17.6% (n = 108) of samples were positive by RT-PCR. I-ELISA detected 41 (38.7%), 32 (39.0%), and 6 (50.0%) positive results in cattle, goats, and sheep sera, respectively, whereas the RT-PCR detected 11 (0.2%), 7 (0.2%), and 1 (0.1%) positive results in cattle, goats, and sheep sera, respectively. These findings have demonstrated the presence of RVFV in Tanzania during the 2006/2007 RVF outbreaks. To our knowledge, this is the first report to detect RVFV in serum samples from domestic animals in Tanzania using PCR technique. Therefore, a detailed molecular study to characterize the virus from different geographical locations in order to establish the profile of strains circulating in the country and develop more effective and efficient control strategies should be done.
Hydrology and simulation of ground-water flow in Kamas Valley, Summit County, Utah
Brooks, L.E.; Stolp, B.J.; Spangler, L.E.
2003-01-01
Kamas Valley, Utah, is located about 50 miles east of Salt Lake City and is undergoing residential development. The increasing number of wells and septic systems raised concerns of water managers and prompted this hydrologic study. About 350,000 acre-feet per year of surface water flows through Kamas Valley in the Weber River, Beaver Creek, and Provo River, which originate in the Uinta Mountains east of the study area. The ground-water system in this area consists of water in unconsolidated deposits and consolidated rock; water budgets indicate very little interaction between consolidated rock and unconsolidated deposits. Most recharge to consolidated rock occurs at higher altitudes in the mountains and discharges to streams and springs upgradient of Kamas Valley. About 38,000 acre-feet per year of water flows through the unconsolidated deposits in Kamas Valley. Most recharge is from irrigation and seepage from major streams; most discharge is to Beaver Creek in the middle part of the valley. Long-term water-level fluctuations range from about 3 to 17 feet. Seasonal fluctuations exceed 50 feet. Transmissivity varies over four orders of magnitude in both the unconsolidated deposits and consolidated rock and is typically 1,000 to 10,000 feet squared per day in unconsolidated deposits and 100 feet squared per day in consolidated rock as determined from specific capacity. Water samples collected from wells, streams, and springs had nitrate plus nitrite concentrations (as N) substantially less than 10 mg/L. Total and fecal coliform bacteria were detected in some surface-water samples and probably originate from livestock. Septic systems do not appear to be degrading water quality. A numerical ground-water flow model developed to test the conceptual understanding of the ground-water system adequately simulates water levels and flow in the unconsolidated deposits. Analyses of model fit and sensitivity were used to refine the conceptual and numerical models.
Carey, A.E.; Prudic, David E.
1996-01-01
Documentation is provided of model input and sample output used in a previous report for analysis of ground-water flow and simulated pumping scenarios in Paradise Valley, Humboldt County, Nevada.Documentation includes files containing input values and listings of sample output. The files, in American International Standard Code for Information Interchange (ASCII) or binary format, are compressed and put on a 3-1/2-inch diskette. The decompressed files require approximately 8.4 megabytes of disk space on an International Business Machine (IBM)- compatible microcomputer using the MicroSoft Disk Operating System (MS-DOS) operating system version 5.0 or greater.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-20
..., closures and coils and from graphic arts operations and the provision of sampling and testing facilities...; SDCAPCD Rule 67.16, Metal Container, Graphic Arts Operations; MBUAPCD Rule 205, Provision of Sampling and...
NASA Astrophysics Data System (ADS)
Baldet, Bertrand
2010-05-01
The incertainties due to climate changes are often evocated in order to explain the increase of natural threats. This study aims to explore the dynamics that are at work within the systems of actors dealing with policies for flood risk management and to introduce the evolutions of public action in this field. We will be showing that there are two different levels of changes. The first mutation is based on the integration of (…). This evolution, albeit it isn' t specific with policies for flood risk management, contributes nevertheless to a renewal recognition of the threat. Secondly, we will indicate that the approach of flood risk changed by itself, it is more « including ». In nowadays, to be able to understand natural risk one needs a positioning all-embracing wich is not confined to the hydraulic dimension. To be able to manage the threat one needs to reconsider all the activities of the valley and to put forward a new approach of the natural environment. In order to explain that changes, we will use the resilience concept. In outline, resilience is defined "as the measure of a part of system's capacity to absorb and recover from occurrence of a hazardous event" (Timmerman). This concept allows to describe the system stability and the capacity to confront change and to manage incertainty. The incertainties due to climate change, the troubles to identify the hazards, the multiplicity of representations about the stakes that have to be protected are a lot of factors wich make the flood risk management more complex and lead the system of actors to regular adaptations. This analysis is based on a ethnographic study, we met local government actors, ecological associations, riverside residents associations, experts…. These actors have to manage the floods of the « Touch ». This river is located in south of France, it crosses his valley (…) before to reach the Garonne near to Toulouse. An historic (view) of the management of the river will lead us to understand the current situation and to show the auto-organisation capacity of the system. We suggest by « system » a whole set of elements localisated in the valley. So, we refer to social, economical, politic, technic and natural factors involved with the flood risk management. For a long time, the « Touch » was only considered like a « irrigating canal ». Beforehand, it crossed only farmlands and his management was entrusted to a riverside residents farmers association. However, during the last decades, the zoning of the downstream banks had changed and some villages (d'autrefois) were been densely urbanized and are now considered as great towns. So, the approach of the threat along the river was renewaled. According the new configuration, an intercommunity union was created - wich gather together all the districts crossed by the Touch - and substitued the farmers association. The approach of flood risk was moved : the management of the threat was « private » but with the creation of the intercommunity union became « political » and « public ». Nowadays, the main stake is to operate a balanced management of the flood risk in order to allocate a well-proportioned constraints. The banks zoning - an agricultural upstream and an urbanized downstream - cause an opposition between farming world wich has to be defend and urban population wich needs protection. The public policies for flood risk management have to juggle between various requirements and deal with conflicting interests - we will see that public policies try to rethink agricultural practices (a decrease of irrigation, planting hedges...) and urbanization dynamics. The concept of resilience can explain the activities of the intercommunity union and the pratices of the actors around it. The working of this organization based on a balanced representation of the riverside cities - every city is represented by two delegates whatever the tall of the city - allows the integration of various stakes (agricultural, environmental, urban...). In spite of heterogeneous situations - (…) - we will see that the global approach of the valley permits the integration of risk, the spreading of the culture of risk and allows the auto-organization of the system.
NASA Astrophysics Data System (ADS)
Ağaç, Kübra; Koçak, Kasım; Deniz, Ali
2015-04-01
A time series approach using autoregressive model (AR), moving average model (MA) and seasonal autoregressive integrated moving average model (SARIMA) were used in this study to simulate and forecast daily PM10 concentrations in Kagithane Creek Valley, Istanbul. Hourly PM10 concentrations have been measured in Kagithane Creek Valley between 2010 and 2014 periods. Bosphorus divides the city in two parts as European and Asian parts. The historical part of the city takes place in Golden Horn. Our study area Kagithane Creek Valley is connected with this historical part. The study area is highly polluted because of its topographical structure and industrial activities. Also population density is extremely high in this site. The dispersion conditions are highly poor in this creek valley so it is necessary to calculate PM10 levels for air quality and human health. For given period there were some missing PM10 concentration values so to make an accurate calculations and to obtain exact results gap filling method was applied by Singular Spectrum Analysis (SSA). SSA is a new and efficient method for gap filling and it is an state-of-art modeling. SSA-MTM Toolkit was used for our study. SSA is considered as a noise reduction algorithm because it decomposes an original time series to trend (if exists), oscillatory and noise components by way of a singular value decomposition. The basic SSA algorithm has stages of decomposition and reconstruction. For given period daily and monthly PM10 concentrations were calculated and episodic periods are determined. Long term and short term PM10 concentrations were analyzed according to European Union (EU) standards. For simulation and forecasting of high level PM10 concentrations, meteorological data (wind speed, pressure and temperature) were used to see the relationship between daily PM10 concentrations. Fast Fourier Transformation (FFT) was also applied to the data to see the periodicity and according to these periods models were built in MATLAB an Eviews programmes. Because of the seasonality of PM10 data SARIMA model was also used. The order of autoregression model was determined according to AIC and BIC criteria. The model performances were evaluated from Fractional Bias, Normalized Mean Square Error (NMSE) and Mean Absolute Percentage Error (MAPE). As expected, the results were encouraging. Keywords: PM10, Autoregression, Forecast Acknowledgement The authors would like to acknowledge the financial support by the Scientific and Technological Research Council of Turkey (TUBITAK, project no:112Y319).
Water resources of Lincoln County, Wyoming
Eddy-Miller, C. A.; Plafcan, Maria; Clark, M.L.
1996-01-01
Streamflow and ground-water quantity and quality data were collected and analyzed, 1993 through 1995, and historical data were compiled to summarize the water resources of Lincoln County.Deposits of Quaternary age, in the valleys of the Bear River and Salt River, had the most well development of any geologic unit in the county.The most productive alluvial aquifers were located in the Bear River Valley and Star Valley with pumping wells discharging up to 2,000 gallons perminute. The ground-water connection between the Overthrust Belt and the Green River Basin is restricted as a result of the folding and faulting that occurred during middle Mesozoic and early Cenozoic time. Total water use in Lincoln County during 1993 was estimated to be 405,000 million gallons. Surface water was the source for 98 percent of the water used in the county. Hydroelectric power generation and irrigation used the largest amounts of water. Dissolved-solids concentrations varied greatly for water samples collected from 35 geologic units inventoried. Dissolved-solids concentrations in all water samples from the LaneyMember of the Green River Formation were greater than the Secondary Maximum Contaminant Level of 500 milligrams per liter established by the U.S. Environmental Protection Agency. Statistical analysis of data collected from wells in the Star Valley monitoring study indicated there was no significant difference between data collected during different seasons, and no correlation between the nitrate concentrations and depth to ground water.
Calvert, S.E.; Piper, D.Z.; Baedecker, P.A.
1987-01-01
The distribution of rare earth elements (REE) in ferromanganese nodules from DOMES Site A has been determined by instrumental neutron activation methods. The concentrations of the REE vary markedly. Low concentrations characterize samples from a depression (the valley), in which Quaternary sediments are thin or absent; high concentrations are found in samples from the surrounding abyssal hills (the highlands) where the Quaternary sediment section is relatively thick. Moreover, the valley nodules are strongly depleted in the light trivalent REE (LREE) and Ce compared with nodules from the highlands, some of the former showing negative Ce anomalies. The REE abundances in the nodules are strongly influenced by the REE abundances in coexisting bottom water. Some controls on the REE chemistry of bottom waters include: a) the more effective removal of the LREE relative to the HREE from seawater because of the greater degree of complexation of the latter elements with seawater ligands, b) the very efficient oxidative scavenging of Ce on particle surfaces in seawater, and c) the strong depletion of both Ce and the LREE in, or a larger benthic flux of the HREE into, the Antarctic Bottom Water (AABW) which flows through the valley. The distinctive REE chemistry of valley nodules is a function of their growth from geochemically evolved AABW. In contrast, the REE chemistry of highland nodules indicates growth from a local, less evolved seawater source. ?? 1987.
Hagerty, Christina H; Anderson, Nicole P; Mundt, Christopher C
2017-03-01
Fungicide resistance can cause disease control failure in agricultural systems, and is particularly concerning with Zymoseptoria tritici, the causal agent of Septoria tritici blotch of wheat. In North America, the first quinone outside inhibitor resistance in Z. tritici was discovered in the Willamette Valley of Oregon in 2012, which prompted this hierarchical survey of commercial winter wheat fields to monitor azoxystrobin- and propiconazole-resistant Z. tritici. Surveys were conducted in June 2014, January 2015, May 2015, and January 2016. The survey was organized in a hierarchical scheme: regions within the Willamette Valley, fields within the region, transects within the field, and samples within the transect. Overall, frequency of azoxystrobin-resistant isolates increased from 63 to 93% from June 2014 to January 2016. Resistance to azoxystrobin increased over time even within fields receiving no strobilurin applications. Propiconazole sensitivity varied over the course of the study but, overall, did not significantly change. Sensitivity to both fungicides showed no regional aggregation within the Willamette Valley. Greater than 80% of spatial variation in fungicide sensitivity was at the smallest hierarchical scale (within the transect) of the survey for both fungicides, and the resistance phenotypes were randomly distributed within sampled fields. Results suggest a need for a better understanding of the dynamics of fungicide resistance at the landscape level.
USSR and Eastern Europe Scientific Abstracts, Biomedical and Behavioral Sciences, Number 85
1978-01-12
OF INVESTIGATION OF SAMPLES OF SPRING WHEAT OF THE WORLD -WIDE COLLECTION OF THE ALL-UNION SCIENTIFIC RESEARCH INSTITUTE...Institute of Agri- culture on about 2,000 specimens of spring wheat from 50 nations of the world taken from the collection of the Ail-Union Scientific...for 2-3 weeks, while leukemoid reactions during other diseases were found much less frequently. In $k.1% of the patients with eosinophilia
Injuries in Australian school-level rugby union.
Leung, Felix T; Franettovich Smith, Melinda M; Hides, Julie A
2017-11-01
There is a high incidence of injuries in rugby union due to the physical nature of the game. In youth rugby union, there are large variations in injury rates reported. Our study investigated the rates of injuries in school-level rugby union players in Australia using the consensus statement for rugby union injuries. Injury surveillance was conducted on 480 rugby players from 1 school in Queensland, Australia. Injury data were collected using paper-based injury recording forms during the 8-week rugby season using a "medical-attention" injury definition. In total, 76 players sustained one or more injuries, with a total of 80 injuries recorded. The overall injury rate was 31.8 injuries/1000 match player hours (95% CI, 25.4-39.4). Concussion had an incidence rate of 6.0/1000 match player hours (95% CI, 3.5-9.6). The incidence of upper limb and lower limb injuries were 9.1 and 9.9/1000 match player hours, respectively (95% CI, 5.9-13.5 and 6.6-14.5). The older age divisions had higher injury rates and most injuries occurred while tackling or being tackled. The injury rates observed in this sample of Australian school rugby union players provides direction for future studies to enable informed decisions relating to development of injury prevention programmes at this level of rugby.
Lundgren, Robert F.; Vining, Kevin C.
2013-01-01
The Turtle Mountain Indian Reservation relies on groundwater supplies to meet the demands of community and economic needs. The U.S. Geological Survey, in cooperation with the Turtle Mountain Band of Chippewa Indians, examined historical groundwater-level and groundwater-quality data for the Fox Hills, Hell Creek, Rolla, and Shell Valley aquifers. The two main sources of water-quality data for groundwater were the U.S. Geological Survey National Water Information System database and the North Dakota State Water Commission database. Data included major ions, trace elements, nutrients, field properties, and physical properties. The Fox Hills and Hell Creek aquifers had few groundwater water-quality data. The lack of data limits any detailed assessments that can be made about these aquifers. Data for the Rolla aquifer exist from 1978 through 1980 only. The concentrations of some water-quality constituents exceeded the U.S. Environmental Protection Agency secondary maximum contaminant levels. No samples were analyzed for pesticides and hydrocarbons. Numerous water-quality samples have been obtained from the Shell Valley aquifer. About one-half of the water samples from the Shell Valley aquifer had concentrations of iron, manganese, sulfate, and dissolved solids that exceeded the U.S. Environmental Protection Agency secondary maximum contaminant levels. Overall, the data did not indicate obvious patterns in concentrations.
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.
Potential for autoimmune pathogenesis of Rift Valley Fever virus retinitis.
Newman-Gerhardt, Shoshana; Muiruri, Samuel; Muchiri, Eric; Peters, Clarence J; Morrill, John; Lucas, Alexander H; King, Charles H; Kazura, James; LaBeaud, Angelle Desiree
2013-09-01
Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans with retinitis (n = 8) were slightly more likely to have antibodies against retinal tissue than control populations, but the correlation was not statistically significant. Further investigation into the possible immune pathogenesis of RVFV retinitis could lead to improved therapies to prevent or treat this severe complication.
Potential for Autoimmune Pathogenesis of Rift Valley Fever Virus Retinitis
Newman-Gerhardt, Shoshana; Muiruri, Samuel; Muchiri, Eric; Peters, Clarence J.; Morrill, John; Lucas, Alexander H.; King, Charles H.; Kazura, James; LaBeaud, Angelle Desiree
2013-01-01
Rift Valley Fever (RVF) is a significant threat to human health because it can progress to retinitis, encephalitis, and hemorrhagic fever. The timing of onset of Rift Valley Fever virus (RVFV) retinitis suggests an autoimmune origin. To determine whether RVFV retinitis is associated with increased levels of IgG against retinal tissue, we measured and compared levels of IgG against healthy human eye tissue by immunohistochemical analysis. We found that serum samples from RVFV-exposed Kenyans with retinitis (n = 8) were slightly more likely to have antibodies against retinal tissue than control populations, but the correlation was not statistically significant. Further investigation into the possible immune pathogenesis of RVFV retinitis could lead to improved therapies to prevent or treat this severe complication. PMID:23918215
In situ gamma-spectrometry several years after deposition of radiocesium. II. Peak-to-valley method.
Gering, F; Hillmann, U; Jacob, P; Fehrenbacher, G
1998-12-01
A new method is introduced for deriving radiocesium soil contaminations and kerma rates in air from in situ gamma-ray spectrometric measurements. The approach makes use of additional information about gamma-ray attenuation given by the peak-to-valley ratio, which is the ratio of the count rates for primary and forward scattered photons. In situ measurements are evaluated by comparing the experimental data with the results of Monte Carlo simulations of photon transport and detector response. The influence of photons emitted by natural radionuclides on the calculation of the peak-to-valley ratio is carefully analysed. The new method has been applied to several post-Chernobyl measurements and the results agreed well with those of soil sampling.
Wang, Zhong; Bhattacharyya, Timothy
2015-01-01
Surgical care and pain management for patients with fractures have evolved over the years. We wanted to ascertain if there were any changes in the incidence of non-unions and, if so, whether the use of non-steroidal anti-inflammatory drugs (NSAIDs), including COX-2 selective inhibitors, might have an effect. We used the National Inpatient Sample (NIS) to estimate the annual number of patients hospitalized for surgical treatment of a non-union between 1993 and 2012, and calculated age-adjusted rates of non-union. We estimated the prevalence of prescriptions for NSAIDs from 1996 through 2012 using the Medical Expenditure Panel Survey (MEPS). The interrupted time-series analysis was used to relate quarterly rates of non-union to changes in prescriptions for NSAIDs between 1996 and 2009. The annual estimate of non-unions in the USA declined 30% from 25,634 in 1993 to 17,815 in 2012 (p < 0.001). Specifically, the age-adjusted rate of non-unions decreased by 44% from 8.6 per 10(5) persons in 1996 to 4.8 per 10(5) persons in 2012 (p < 0.001). However, there was an 8% increase in the incidence rate of non-unions (p = 0.003) between 2000 and 2004, when certain COX-2 selective inhibitors were on the market and their prescriptions were prevalent at around 6% among those with fractures. A drop in non-union estimates from 22,321 in 2010 to 18,789 in 2011 (p = 0.04) also coincided with a marked decrease in prescriptions for NSAIDs in patients with fractures, from 22% to 14% (p = 0.02). Non-unions in the USA declined substantially between 1993 and 2012, but this was interrupted by changes in prescriptions for NSAIDs, with sustained increases between 2000 and 2004 followed by transient decreases in 2005 and 2011.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-20
..., closures and coils, from graphic arts operations, from the provision of sampling and testing facilities... Provision of Sampling and Revised 03/21/01....... 05/31/01 Testing Facilities. AVAQMD 1168 Adhesive and... District (1) Rule 205, ``Provision of Sampling and Testing Facilities,'' revised on March 21, 2001...
Lead (Pb) in sheep exposed to mining pollution: implications for animal and human health.
Pareja-Carrera, Jennifer; Mateo, Rafael; Rodríguez-Estival, Jaime
2014-10-01
Livestock from the ancient mining area of Sierra Madrona and Alcudia Valley (Spain) is exposed to elevated levels of lead (Pb), as previous studies based on blood monitoring have revealed. Here we have studied blood, liver and muscle Pb levels in sheep in order to know if Pb exposure could represent a risk for human consumers of the meat and offal of these animals. A cross-sectional study was conducted with ≥4 years old (adults) ewes from the mining area (n=46) and a control area (n=21). Blood samples were taken before the sacrifice at the slaughterhouse, and liver and muscle samples were taken thereafter. At the same time, 2-3 year old rams (subadults, n=17) were blood sampled in the mining area. Blood, liver and muscle Pb levels were higher in the mining than in the control area. Blood Pb concentration in the mining area (n= 44, mean: 6.7μg/dl in ewes and 10.9μg/dl in rams) was above background levels (>6μg/dl) in 73.3 percent of animals. Liver Pb concentration in 68 percent of sheep from the mining area (n=32, mean: 6.16μg/g dry weight, d.w.) exceeded the minimum level associated with toxic exposure (5µg/g d.w.) and 87.5 percent of liver samples were above European Union Maximum Residue Levels (MRL) established for offal destined for human consumption (0.5µg/g w.w.~1.4µg/g d.w.). On the contrary, none of the muscle samples in ewes exceeded the EU MRL (0.1µg/g w.w.~0.34µg/g d.w.) established for meat, which may be related to the decline of blood Pb levels with age observed in the present study. These results suggest a potential health effect for sheep exposed to Pb pollution in this area and implications for food safety, but further research with lamb meat may be necessary to refine the risk assessment for human consumers. Copyright © 2014 Elsevier Inc. All rights reserved.
Sample Size and Allocation of Effort in Point Count Sampling of Birds in Bottomland Hardwood Forests
Winston P. Smith; Daniel J. Twedt; Robert J. Cooper; David A. Wiedenfeld; Paul B. Hamel; Robert P. Ford
1995-01-01
To examine sample size requirements and optimum allocation of effort in point count sampling of bottomland hardwood forests, we computed minimum sample sizes from variation recorded during 82 point counts (May 7-May 16, 1992) from three localities containing three habitat types across three regions of the Mississippi Alluvial Valley (MAV). Also, we estimated the effect...
Galaxy and Mass Assembly (GAMA): variation in galaxy structure across the green valley
NASA Astrophysics Data System (ADS)
Kelvin, Lee S.; Bremer, Malcolm N.; Phillipps, Steven; James, Philip A.; Davies, Luke J. M.; De Propris, Roberto; Moffett, Amanda J.; Percival, Susan M.; Baldry, Ivan K.; Collins, Chris A.; Alpaslan, Mehmet; Bland-Hawthorn, Joss; Brough, Sarah; Cluver, Michelle; Driver, Simon P.; Hashemizadeh, Abdolhosein; Holwerda, Benne W.; Laine, Jarkko; Lara-Lopez, Maritza A.; Liske, Jochen; Maciejewski, Witold; Napolitano, Nicola R.; Penny, Samantha J.; Popescu, Cristina C.; Sansom, Anne E.; Sutherland, Will; Taylor, Edward N.; van Kampen, Eelco; Wang, Lingyu
2018-07-01
Using a sample of 472 local Universe (z < 0.06) galaxies in the stellar mass range 10.25 {<} log {M}_{\\star }/{M}_{⊙} {<} 10.75, we explore the variation in galaxy structure as a function of morphology and galaxy colour. Our sample of galaxies is subdivided into red, green, and blue colour groups and into elliptical and non-elliptical (disk-type) morphologies. Using Kilo-Degree Survey (KiDS) and Visible and Infrared Survey Telescope for Astronomy (VISTA) Kilo-Degree Infrared Galaxy Survey (VIKING) derived postage stamp images, a group of eight volunteers visually classified bars, rings, morphological lenses, tidal streams, shells, and signs of merger activity for all systems. We find a significant surplus of rings (2.3σ) and lenses (2.9σ) in disk-type galaxies as they transition across the green valley. Combined, this implies a joint ring/lens green valley surplus significance of 3.3σ relative to equivalent disk-types within either the blue cloud or the red sequence. We recover a bar fraction of {˜ }44 per cent which remains flat with colour, however, we find that the presence of a bar acts to modulate the incidence of rings and (to a lesser extent) lenses, with rings in barred disk-type galaxies more common by ˜20-30 percentage points relative to their unbarred counterparts, regardless of colour. Additionally, green valley disk-type galaxies with a bar exhibit a significant 3.0σ surplus of lenses relative to their blue/red analogues. The existence of such structures rules out violent transformative events as the primary end-of-life evolutionary mechanism, with a more passive scenario the favoured candidate for the majority of galaxies rapidly transitioning across the green valley.
Galaxy and Mass Assembly (GAMA): Variation in Galaxy Structure Across the Green Valley
NASA Astrophysics Data System (ADS)
Kelvin, Lee S.; Bremer, Malcolm N.; Phillipps, Steven; James, Philip A.; Davies, Luke J. M.; De Propris, Roberto; Moffett, Amanda J.; Percival, Susan M.; Baldry, Ivan K.; Collins, Chris A.; Alpaslan, Mehmet; Bland-Hawthorn, Joss; Brough, Sarah; Cluver, Michelle; Driver, Simon P.; Hashemizadeh, Abdolhosein; Holwerda, Benne W.; Laine, Jarkko; Lara-Lopez, Maritza A.; Liske, Jochen; Maciejewski, Witold; Napolitano, Nicola R.; Penny, Samantha J.; Popescu, Cristina C.; Sansom, Anne E.; Sutherland, Will; Taylor, Edward N.; van Kampen, Eelco; Wang, Lingyu
2018-04-01
Using a sample of 472 local Universe (z < 0.06) galaxies in the stellar mass range 10.25< log M_{\\star }/M_{⊙}<10.75, we explore the variation in galaxy structure as a function of morphology and galaxy colour. Our sample of galaxies is sub-divided into red, green and blue colour groups and into elliptical and non-elliptical (disk-type) morphologies. Using KiDS and VIKING derived postage stamp images, a group of eight volunteers visually classified bars, rings, morphological lenses, tidal streams, shells and signs of merger activity for all systems. We find a significant surplus of rings (2.3σ) and lenses (2.9σ) in disk-type galaxies as they transition across the green valley. Combined, this implies a joint ring/lens green valley surplus significance of 3.3σ relative to equivalent disk-types within either the blue cloud or the red sequence. We recover a bar fraction of ˜44% which remains flat with colour, however, we find that the presence of a bar acts to modulate the incidence of rings and (to a lesser extent) lenses, with rings in barred disk-type galaxies more common by ˜20 - 30 percentage points relative to their unbarred counterparts, regardless of colour. Additionally, green valley disk-type galaxies with a bar exhibit a significant 3.0σ surplus of lenses relative to their blue/red analogues. The existence of such structures rules out violent transformative events as the primary end-of-life evolutionary mechanism, with a more passive scenario the favoured candidate for the majority of galaxies rapidly transitioning across the green valley.
NASA Astrophysics Data System (ADS)
Arata, Laura; Meusburger, Katrin; Zehringer, Markus; Ketterer, Michael E.; Mabit, Lionel; Alewell, Christine
2016-04-01
Improper land management and climate change has resulted in accelerated soil erosion rates in Alpine grasslands. To efficiently mitigate and control soil erosion and reduce its environmental impact in Alpine grasslands, reliable and validated methods for comprehensive data generation on its magnitude and spatial extent are mandatory. The use of conventional techniques (e.g. sediment traps, erosion pins or rainfall simulations) may be hindered by the extreme topographic and climatic conditions of the Alps. However, the application of the Fallout Radionuclides (FRNs) as soil tracers has already showed promising results in these specific agro-ecosystems. Once deposited on the ground, FRNs strongly bind to fine particles at the surface soil and move across the landscape primarily through physical processes. As such, they provide an effective track of soil and sediment redistribution. So far, applications of FRN in the Alps include 137Cs (half-life: 30.2 years) and 239+240Pu (239Pu [half-life = 24110 years] and 240Pu [half-life = 6561 years]). To investigate short term (4-5 years) erosion dynamics in the Swiss Alps, the authors applied a FRNs repeated sampling approach. Two study areas in the central Swiss Alps have been investigated: the Urseren Valley (Canton Uri), where significant land use changes occurred in the last centuries, and the Piora Valley (Canton Ticino), where land use change plays a minor role. Soil samples have been collected at potentially erosive sites along the valleys over a period of 4-5 years and measured for 137Cs and 239+240Pu activity. The inventory change between the sampling years indicates high erosion and deposition dynamics at both valleys. High spatial variability of 137Cs activities at all sites has been observed, reflecting the heterogeneous distribution of 137Cs fallout after the Chernobyl power plant accident in 1986. Finally, a new modelling technique to convert the inventory changes to quantitative estimates of soil erosion has been tested.
Wintertime Ambient Ammonia Concentrations in Northern Utah's Urban Valleys
NASA Astrophysics Data System (ADS)
Hammond, I. A.; Martin, R. S.; Silva, P.; Baasandorj, M.
2017-12-01
Many of the population centers in northern Utah are currently classified as non-attainment or serious non-attainment, Wasatch Front, for PM2.5 and previous studies have shown ammonium nitrate to often be the largest contributor to the particulate mass. Furthermore, measurements have shown several of the Wasatch Front cities and Cache Valley (UT/ID) consistently recorded some of the highest ambient ammonia (NH3) concentrations in the continental United States. As a part of the multi-organization 2017 Utah Winter Fine Particulate Study real-time NH3 concentrations were monitored in the Cache Valley at the Logan, UT site, collocated at an EPA sampling trailer near the Utah State University (USU) campus. A Picarro model G2508 was to used collect 5-sec averaged concentrations of NH3, carbon dioxide (CO2), and methane (CH4) from January 16th to February 14th, 2017. Parts of three inversion events, wherein the PM2.5 concentrations approached or exceeded the National Ambient Air Quality Standards, were captured during the sampling period, including a 10-day event from January 25th to February 4th. Concentrations of all three of the observed species showed significant accumulation during the events, with NH3 concentrations ranging from below the detection limit (<0.5 ppb) to >70 ppb. Preliminary analysis suggested the temporal NH3 changes tracked the increase in PM2.5 throughout the inversion events; however, a one-day period of NH3 depletion during the main inversion event was observed while PM2.5 continued to increase. Additionally, a network of passive NH3 samplers (Ogawa Model 3300) were arrayed at 25 sites throughout the Cache Valley and at 11 sites located along the Wasatch Front. These networks sampled for three 7-day periods, during the same study time frame. Ion chromatographic (IC) analyses of the sample pads are not yet finalized; however, preliminary results show concentrations in the tens of ppb and seemingly spatially correlate with previous studies showing elevated wintertime values.
Ground-water data, 1969-77, Vandenberg Air Force Base area, Santa Barbara County, California
Lamb, Charles E.
1980-01-01
The water supply for Vandenberg Air Force Base is obtained from wells in the Lompoc Plain, San Antonio Valley, and Lompoc Terrace groundwater basins. Metered pumpage during the period 1969-77 from the Lompoc Plain decreased from a high of 3,670 acre-feet in 1969 to a low of 2,441 acre-feet in 1977, while pumpage from the San Antonio Valley increased from a low of 1 ,020 acre-feet in 1969 to a high of 1,829 acre-feet in 1977. Pumpage from the Lompoc Terrace has remained relatively constant and was 187 acre-feet in 1977. In the Barka Slough area of the San Antonio Valley, water levels in four shallow wells declined during 1976 and 1977. Water levels in observation wells in the two aquifers of the Lompoc Terrace ground-water basin fluctuated during the period, but show no long term trends. Chemical analyses or field determinations of temperature and specific conductance were made of 219 water samples collected from 53 wells. In the Lompoc Plain the dissolved-solids concentration in all water samples was more than 625 milligrams per liter, and in most was more than 1,000 milligrams per liter. The manganese concentration in analyzed samples equaled or exceeded the recommended limit of 50 micrograms per liter for public water supplies. Dissolved-solids concentrations increased with time in water samples from two wells east of the Air Force Base in San Antonio Valley. In the base well-field area, concentrations of dissolved solids ranged from 290 to 566 milligrams per liter. Eight analyses show manganese at or above the recommended limit of 50 milligrams per liter. In the Lompoc Terrace area dissolved-solids concentrations ranged from 470 to 824 milligrams per liter. Five new supply wells, nine observation wells, and two exploratory/observation wells were drilled on the base during the period 1972-77. (USGS)
La Ferla, Rosabruna; Azzaro, Maurizio; Michaud, Luigi; Caruso, Gabriella; Lo Giudice, Angelina; Paranhos, Rodolfo; Cabral, Anderson S; Conte, Antonella; Cosenza, Alessandro; Maimone, Giovanna; Papale, Maria; Rappazzo, Alessandro Ciro; Guglielmin, Mauro
2017-08-01
Victoria Land permafrost harbours a potentially large pool of cold-affected microorganisms whose metabolic potential still remains underestimated. Three cores (BC-1, BC-2 and BC-3) drilled at different depths in Boulder Clay (Northern Victoria Land) and one sample (DY) collected from a core in the Dry Valleys (Upper Victoria Valley) were analysed to assess the prokaryotic abundance, viability, physiological profiles and potential metabolic rates. The cores drilled at Boulder Clay were a template of different ecological conditions (different temperature regime, ice content, exchanges with atmosphere and with liquid water) in the same small basin while the Dry Valleys site was very similar to BC-2 conditions but with a complete different geological history and ground ice type. Image analysis was adopted to determine cell abundance, size and shape as well as to quantify the potential viable and respiring cells by live/dead and 5-cyano-2,3-ditolyl-tetrazolium chloride staining, respectively. Subpopulation recognition by apparent nucleic acid contents was obtained by flow cytometry. Moreover, the physiological profiles at community level by Biolog-Ecoplate™ as well as the ectoenzymatic potential rates on proteinaceous (leucine-aminopeptidase) and glucidic (ß-glucosidase) organic matter and on organic phosphates (alkaline-phosphatase) by fluorogenic substrates were tested. The adopted methodological approach gave useful information regarding viability and metabolic performances of microbial community in permafrost. The occurrence of a multifaceted prokaryotic community in the Victoria Land permafrost and a large number of potentially viable and respiring cells (in the order of 10 4 -10 5 ) were recognised. Subpopulations with a different apparent DNA content within the different samples were observed. The physiological profiles stressed various potential metabolic pathways among the samples and intense utilisation rates of polymeric carbon compounds and carbohydrates, mainly in deep samples. The measured enzymatic activity rates suggested the potential capability of the microbial community to decompose proteins and polysaccharides. The microbial community seems to be appropriate to contribute to biogeochemical cycling in this extreme environment.
Sheets, Rodney A.; Bair, E. Scott; Rowe, Gary L.
1998-01-01
Combined use of the tritium/helium 3 (3H/3He) dating technique and particle-tracking analysis can improve flow-model calibration. As shown at two sites in the Great Miami buried-valley aquifer in southwestern Ohio, the combined use of 3H/3He age dating and particle tracking led to a lower mean absolute error between measured heads and simulated heads than in the original calibrated models and/or between simulated travel times and 3H/3He ages. Apparent groundwater ages were obtained for water samples collected from 44 wells at two locations where previously constructed finite difference models of groundwater flow were available (Mound Plant and Wright-Patterson Air Force Base (WPAFB)). The two-layer Mound Plant model covers 11 km2 within the buried-valley aquifer. The WPAFB model has three layers and covers 262 km2 within the buried-valley aquifer and adjacent bedrock uplands. Sampled wells were chosen along flow paths determined from potentiometric maps or particle-tracking analyses. Water samples were collected at various depths within the aquifer. In the Mound Plant area, samples used for comparison of 3H/3He ages with simulated travel times were from wells completed in the uppermost model layer. Simulated travel times agreed well with 3H/3He ages. The mean absolute error (MAE) was 3.5 years. Agreement in ages at WPAFB decreased with increasing depth in the system. The MAEs were 1.63, 17.2, and 255 years for model layers 1, 2, and 3, respectively. Discrepancies between the simulated travel times and 3H/3He ages were assumed to be due to improper conceptualization or incorrect parameterization of the flow models. Selected conceptual and parameter modifications to the models resulted in improved agreement between 3H/3He ages and simulated travel times and between measured and simulated heads and flows.
NASA Astrophysics Data System (ADS)
Colombo, Ferran; Busquets, Pere; Sole de Porta, Nuria; Limarino, Carlos Oscar; Heredia, Nemesio; Rodriguez-Fernandez, Luis Roberto; Alvarez-Marron, Joaquina
2009-10-01
The Jáchal River Valley displays a number of significant Holocene sedimentary accumulations made up of fine-grained materials. These deposits are interpreted as the sedimentary infill of shallow temporary lakes that were generated by slow growing episodes of alluvial fans that obstructed the Jáchal River Valley. The association of fossil remains through the Holocene sedimentary sequence suggests that the accumulation of lacustrine sediments was affected by climate variations. The predominant aridity was punctuated by very few humid episodes characterised by fresh-water gastropoda and the intercalations of muddy sediments. The high proportion of charcoal particles in some samples indicates periodic forest fires. Abundant non-pollen forest remains suggest that an open zone dominated by several types of grasses underwent a dry season during part of the year. The palynomorph associations found in the Jáchal River Valley Holocene lacustrine sediments suggest that the humid conditions were less intense than those in the San Juan River Valley located more than one hundred kilometres southwards. Our study suggests that lake formation could have been controlled by climate oscillation probably related to the ENSO variation at 30° south latitude.
Deglaciation chronology in the Mérida Andes from cosmogenic 10Be dating, (Gavidia valley, Venezuela)
NASA Astrophysics Data System (ADS)
Angel, Isandra; Audemard M., Franck A.; Carcaillet, Julien; Carrillo, Eduardo; Beck, Christian; Audin, Laurence
2016-11-01
In the Mérida Andes, a detailed deglaciation history reconstruction is difficult to achieve due to scattered deglaciation chronologies available. This paper contributes with 24 exposure ages of glacial landforms sampled in the Gavidia valley. Exposure ages were obtained based on terrestrial cosmogenic nuclide 10Be dating. Results indicate deglaciation mainly occurred between ∼21 ka and 16.5 ka and the complete deglaciation occurred at ∼16.0 ka. The glacier retreated in two different phases. The oldest one occurred since the LGM until middle OtD or the local climate event El Caballo Stadial. The youngest phase occurred at ages younger than ∼16.5 ka until complete deglaciation. A combination of topographic features and changes in the paleoclimate conditions at the end of the El Caballo Stadial seems leaded the fastest former glacier extinction. The topographic feature which seems contributed to the fastest glacier extinction was the low valley bottom slopes. In addition, exposure ages of the Gavidia valley were integrated with deglaciation chronologies from the central Mérida Andes to compare deglaciation histories. Asynchronous deglaciation histories were observed. Local paleotemperatures and paleoprecipitations contrasts, different valleys aspects, insolation and catchments steepness could explain different deglaciation histories.
Pesticides and amphibian population declines in California, USA
Sparling, Donald W.; Fellers, Gary M.; McConnell, Laura L.
2001-01-01
Several species of anuran amphibians have undergone drastic population declines in the western United States over the last 10 to 15 years. In California, the most severe declines are in the Sierra Mountains east of the Central Valley and downwind of the intensely agricultural San Joaquin Valley. In contrast, coastal and more northern populations across from the less agrarian Sacramento Valley are stable or declining less precipitously. In this article, we provide evidence that pesticides are instrumental in declines of these species. Using Hyla regilla as a sentinel species, we found that cholinesterase (ChE) activity in tadpoles was depressed in mountainous areas east of the Central Valley compared with sites along the coast or north of the Valley. Cholinesterase was also lower in areas where ranid population status was poor or moderate compared with areas with good ranid status. Up to 50% of the sampled population in areas with reduced ChE had detectable organophosphorus residues, with concentrations as high as 190 ppb wet weight. In addition, up to 86% of some populations had measurable endosulfan concentrations and 40% had detectable 4,4'- dichlorodiphenyldichloroethylene, 4,4'-DDT, and 2,4'-DDT residues.
Inventory of amphibians and reptiles at Death Valley National Park
Persons, Trevor B.; Nowak, Erika M.
2006-01-01
As part of the National Park Service Inventory and Monitoring Program in the Mojave Network, we conducted an inventory of amphibians and reptiles at Death Valley National Park in 2002-04. Objectives for this inventory were to: 1) Inventory and document the occurrence of reptile and amphibian species occurring at DEVA, primarily within priority sampling areas, with the goal of documenting at least 90% of the species present; 2) document (through collection or museum specimen and literature review) one voucher specimen for each species identified; 3) provide a GIS-referenced list of sensitive species that are federally or state listed, rare, or worthy of special consideration that occur within priority sampling locations; 4) describe park-wide distribution of federally- or state-listed, rare, or special concern species; 5) enter all species data into the National Park Service NPSpecies database; and 6) provide all deliverables as outlined in the Mojave Network Biological Inventory Study Plan. Methods included daytime and nighttime visual encounter surveys, road driving, and pitfall trapping. Survey effort was concentrated in predetermined priority sampling areas, as well as in areas with a high potential for detecting undocumented species. We recorded 37 species during our surveys, including two species new to the park. During literature review and museum specimen database searches, we recorded three additional species from DEVA, elevating the documented species list to 40 (four amphibians and 36 reptiles). Based on our surveys, as well as literature and museum specimen review, we estimate an overall inventory completeness of 92% for Death Valley and an inventory completeness of 73% for amphibians and 95% for reptiles. Key Words: Amphibians, reptiles, Death Valley National Park, Inyo County, San Bernardino County, Esmeralda County, Nye County, California, Nevada, Mojave Desert, Great Basin Desert, inventory, NPSpecies.
Rice, Karen C.; Monti, Michele M.; Ettinger, Matthew R.
2005-01-01
Concentrated animal feeding operations (CAFOs) result from the consolidation of small farms with animals into larger operations, leading to a higher density of animals per unit of land on CAFOs than on small farms. The density of animals and subsequent concentration of animal wastes potentially can cause contamination of nearby ground and surface waters. This report summarizes water-quality data collected from agricultural sites in the Shenandoah Valley and Eastern Shore of Virginia. Five sites, three non-CAFO and two dairy-operation CAFO sites, were sampled in the Shenandoah Valley. Four sites, one non-CAFO and three poultry-operation CAFO sites were sampled on the Eastern Shore. All samples were collected during January and February 2004. Water samples were analyzed for the following parameters and constituents: temperature, specific conductance, pH, and dissolved oxygen; concentrations of the indicator organisms Escherichia coli (E. coli) and enterococci; bacterial isolates of E. coli, enterococci, Salmonella spp., and Campylobacter spp.; sensitivity to antibiotics of E. coli, enterococci, and Salmonella spp.; arsenic, cadmium, chromium3+, copper, nickel, and mercury; hardness, biological oxygen demand, nitrate, nitrite, ammonia, ortho-phosphate, total Kjeldahl nitrogen, chemical oxygen demand, total organic carbon, and dissolved organic carbon; and 45 dissolved organic compounds, which included a suite of antibiotic compounds.Data are presented in tables 5-21 and results of analyses of replicate samples are presented in tables 22-28. A summary of the data in tables 5-8 and 18-21 is included in the report.
Mechanical Properties of Sprinting in Elite Rugby Union and Rugby League.
Cross, Matt R; Brughelli, Matt; Brown, Scott R; Samozino, Pierre; Gill, Nicholas D; Cronin, John B; Morin, Jean-Benoît
2015-09-01
To compare mechanical properties of overground sprint running in elite rugby union and rugby league athletes. Thirty elite rugby code (15 rugby union and 15 rugby league) athletes participated in this cross-sectional analysis. Radar was used to measure maximal overground sprint performance over 20 or 30 m (forwards and backs, respectively). In addition to time at 2, 5, 10, 20, and 30 m, velocity-time signals were analyzed to derive external horizontal force-velocity relationships with a recently validated method. From this relationship, the maximal theoretical velocity, external relative and absolute horizontal force, horizontal power, and optimal horizontal force for peak power production were determined. While differences in maximal velocity were unclear between codes, rugby union backs produced moderately faster split times, with the most substantial differences occurring at 2 and 5 m (ES 0.95 and 0.86, respectively). In addition, rugby union backs produced moderately larger relative horizontal force, optimal force, and peak power capabilities than rugby league backs (ES 0.73-0.77). Rugby union forwards had a higher absolute force (ES 0.77) despite having ~12% more body weight than rugby league forwards. In this elite sample, rugby union athletes typically displayed greater short-distance sprint performance, which may be linked to an ability to generate high levels of horizontal force and power. The acceleration characteristics presented in this study could be a result of the individual movement and positional demands of each code.
Linking plant hydraulics and beta diversity in tropical forests
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christoffersen, Bradley; Meir, Patrick; McDowell, Nate G.
In tropical forests, studies of xylem traits governing water transport through plants, or ‘hydraulic architecture’ (Tyree et al., 1991), and changes in species composition across environmental gradients, or ‘beta diversity’ (Gentry, 1988; Ackerly & Cornwell, 2007), have progressedmostly in parallel until recently (Hao et al., 2008; Bartlett et al., 2016). In this issue of New Phytologist, Cosme et al. (pp. 000–5 000) present a timely contribution to the intersection of plant hydraulic architecture (HA) with trait-based community ecology. Building on previous biogeographical work that demonstrated shifts in species composition (beta diversity) across a gradient from valleys to plateaus in centralmore » Amazonia (Schietti et al., 2014), Cosme et al. explore how variation in HA might underpin this sorting, sampling pairs of congeneric species restrictedmostly to either plateau or valley habitats. Valley species had significantly lower wood density and higher hydraulically-weighted vessel diameter and vessel area. By contrast, trees with some of the largest hydraulically-weighted vessel diameters existed in tall, deciduous plateau species, while the leaf: sapwood area ratio decreased with height in valley but not plateau species. These intriguing results suggest that species differentiation in water transport traits mediate edaphic filtering along the valley-toplateau gradient, in contrast to previous work where wood mechanical support mediated valley-to-plateau environmental filtering (Fortunel et al., 2014).« less
NASA Astrophysics Data System (ADS)
Khan, A. L.; McKnight, D. M.; Williams, M. W.; Armstrong, R. L.
2016-12-01
To investigate the impacts of the 2015 earthquakes on water quality and resources in the Gokyo Valley, drinking water samples were collected in the Khumbu region of Nepal in early 2016 and compared to baseline data from November 2012. This study was part of a larger USAID funded project housed at the National Snow and Ice Data Center to understand Contributions to High Asian Run-off from Ice and Snow (CHARIS) which has more than 10 local partners across 8 countries in High Asia. The Gokyo Valley is home to the Ngozumba Glacier and the Gokyo Lakes, which serve as the headwaters to the Dudh Koshi River. Samples were collected from tributary streams, which serve as the local drinking water sources and contribute to the Dudh Koshi watershed, along a transect from Lukla, 9181 ft, to Gokyo, 15, 557 ft. Water samples were analyzed in the field with the Aquagenx, Compartment Bag Test, a low cost method to detect E.coli, an indicator bacteria of fecal contamination. E.coli was present at the lowest elevations. Water samples were also shipped back to CU-Boulder for further chemical analysis including dissolved organic carbon (DOC), total dissolved nitrogen (TDN), arsenic, and oxygen isotopes to identify changes in hydrologic flow paths. These samples are being analyzed over the summer of 2016. Snow samples were also collected along a transect from Namche Bazaar at 11,657 ft to Gokyo Ri at 17,500 ft and have been analyzed for refractory black carbon (rBC). In general, rBC concentrations decreased with increasing elevation, except near local point-sources. Impurities like these reduce surface albedo and increase the amount of solar radiation absorbed by snow/ice, leading to enhanced melt.
Colgan, J.P.; Shuster, D.L.; Reiners, P.W.
2008-01-01
We use a combination of apatite 4He/3He, (U-Th)/ He, and fission-track thermochronology to date slip on the Surprise Valley fault in northeastern California by analyzing a single sample from the Warner Range in the footwall of the fault. This sample, a granitic clast from a conglomerate, yielded a fission-track age of 11.6 ?? 2.8 Ma and a (U-Th)/He age of 3.02 ?? 0.52 Ma. Geologic relationships indicate that this sample was buried to a depth of ???3.3 km prior to exhumation during slip on the Surprise Valley fault. Fission-track age and length data indicate that the sample was fully reset (>120 ??C) prior to exhumation, which began sometime after 14 Ma. A single aliquot of nine apatite grains was step-heated for 4He/3He analysis; modeling of the resulting 4He distribution indicates that cooling from <80 ??C to ???20 ??C occurred between 3 and 1 Ma. Interconsistent time-temperature (t-T) solutions to the combined 4He/3He, (U-Th)/He, and fission-track data require two distinct periods of cooling, consistent with non-continuous slip on the Surprise Valley fault. Early cooling and fault slip took place between 14 and 8 Ma, followed by more recent fault slip ca. 3 Ma. This timing is consistent with both local geologic relationships and with the regional timing of faulting along the western margin of the Basin and Range Province. These data demonstrate the resolving power of combined fission-track, (U-Th)/He, and 4He/3He thermochronometric data to extract low-temperature t-T information from a single sample close to Earth's surface. ?? 2008 The Geological Society of America.
Pediatric Coccidioidomycosis Patients: Perceptions, Quality of Life and Psychosocial Factors
Gaab, Erin Mary; Naeem, Fouzia
2015-01-01
Research investigating the effects of coccidioidomycosis (valley fever) on children and the psychosocial implications of this disease in general is lacking. This study reviews what is known about pediatric coccidioidomycosis patients. It documents the psychological functioning, quality of life, and illness perceptions of a sample of coccidioidomycosis patient families. Primary caregivers of pediatric patients and patients from a major hospital in the San Joaquin Valley of California were interviewed regarding their perceptions of disease detection, access to care and the patient/family experience. PMID:27417796
Temporal trends in nitrate and selected pesticides in Mid-Atlantic ground water.
Debrewer, Linda M; Ator, Scott W; Denver, Judith M
2008-01-01
Evaluating long-term temporal trends in regional ground-water quality is complicated by variable hydrogeologic conditions and typically slow flow, and such trends have rarely been directly measured. Ground-water samples were collected over near-decadal and annual intervals from unconfined aquifers in agricultural areas of the Mid-Atlantic region, including fractured carbonate rocks in the Great Valley, Potomac River Basin, and unconsolidated sediments on the Delmarva Peninsula. Concentrations of nitrate and selected pesticides and degradates were compared among sampling events and to apparent recharge dates. Observed temporal trends are related to changes in land use and chemical applications, and to hydrogeology and climate. Insignificant differences in nitrate concentrations in the Great Valley between 1993 and 2002 are consistent with relatively steady fertilizer application during respective recharge periods and are likely related to drought conditions in the later sampling period. Detecting trends in Great Valley ground water is complicated by long open boreholes characteristic of wells sampled in this setting which facilitate significant ground-water mixing. Decreasing atrazine and prometon concentrations, however, reflect reported changes in usage. On the Delmarva Peninsula between 1988 and 2001, median nitrate concentrations increased 2 mg per liter in aerobic ground water, reflecting increasing fertilizer applications. Correlations between selected pesticide compounds and apparent recharge date are similarly related to changing land use and chemical application. Observed trends in the two settings demonstrate the importance of considering hydrogeology and recharge date along with changing land and chemical uses when interpreting trends in regional ground-water quality.
Molecular techniques are an alternative to culturing and counting methods in quantifying indoor fungal contamination. Pyrosequencing offers the possibility of identifying unexpected indoor fungi. In this study, 50 house dust samples were collected from homes in the Yakima Valley,...
Intra-storm variability and soluble fractionation was explored for summer-time rain events in Steubenville, Ohio to evaluate the physical processes controlling mercury (Hg) in wet deposition in this industrialized region. Comprehensive precipitation sample collection was conducte...
NASA Astrophysics Data System (ADS)
Acheampong, S. Y.
2007-12-01
A critical component to managing water resources is understanding the source of ground water that is extracted from a well. Detail information on the source of recharge and the age of groundwater is thus vital for the proper assessment, development, management, and monitoring of the groundwater resources in an area. Great differences in the isotopic composition of groundwater in a basin and the basin precipitation imply that the groundwater in the basin originates from a source outside the basin or is recharged under different climatic conditions. The stable isotopes of oxygen and hydrogen in precipitation were compared with the isotopic composition of water from wells, springs, and creeks to evaluate the source of the shallow groundwater recharge in Spring and Snake Valleys, Nevada, as part of an evaluation of the water resources in the area. Delta deuterium and delta oxygen-18 composition of springs, wells, creeks, and precipitation in Spring and Snake Valleys show that groundwater recharge occurs primarily from winter precipitation in the surrounding mountains. The carbon-14 content of the groundwater ranged from 30 to 95 percent modern carbon (pmc). Twenty two of the thirty samples had carbon-14 values of greater than 50 pmc. The relatively high carbon-14 values suggest that groundwater in the area is recharged by modern precipitation and the waters have rapid travel times. Total dissolved solids content of the samples outside the playa areas are generally low, and suggests that the water has a relatively short travel time between the recharge areas and sample sites. The presence of tritium in some of the springs and wells also indicate that groundwater mixes with post 1952 precipitation. Hydrogen bomb tests which began in 1952 in the northern hemisphere added large amounts of tritium to the atmosphere and reached a peak in 1963. The stable isotopic composition, the high carbon-14 activities, and the presence of tritium, show that the shallow groundwater in Snake and Spring Valleys originates as modern recharge. The shallow groundwater in these valleys is thus a renewable resource and can be developed in a sustainable manner using the appropriate planning and management tools.
Saadat, Victoria M
2015-01-01
The dissolution of the USSR resulted in independence for constituent republics but left them battling an unstable economic environment and healthcare. Increases in injection drug use, prostitution, and migration were all widespread responses to this transition and have contributed to the emergence of an HIV epidemic in the countries of former Soviet Union. Researchers have begun to identify the risks of HIV infection as well as the barriers to HIV testing and treatment in the former Soviet Union. Significant methodological challenges have arisen and need to be addressed. The objective of this review is to determine common threads in HIV research in the former Soviet Union and provide useful recommendations for future research studies. In this systematic review of the literature, Pubmed was searched for English-language studies using the key search terms "HIV", "AIDS", "human immunodeficiency virus", "acquired immune deficiency syndrome", "Central Asia", "Kazakhstan", "Kyrgyzstan", "Uzbekistan", "Tajikistan", "Turkmenistan", "Russia", "Ukraine", "Armenia", "Azerbaijan", and "Georgia". Studies were evaluated against eligibility criteria for inclusion. Thirty-nine studies were identified across the two main topic areas of HIV risk and barriers to testing and treatment, themes subsequently referred to as "risk" and "barriers". Study design was predominantly cross-sectional. The most frequently used sampling methods were peer-to-peer and non-probabilistic sampling. The most frequently reported risks were condom misuse, risky intercourse, and unsafe practices among injection drug users. Common barriers to testing included that testing was inconvenient, and that results would not remain confidential. Frequent barriers to treatment were based on a distrust in the treatment system. The findings of this review reveal methodological limitations that span the existing studies. Small sample size, cross-sectional design, and non-probabilistic sampling methods were frequently reported limitations. Future work is needed to examine barriers to testing and treatment as well as longitudinal studies on HIV risk over time in most-at-risk populations.
NASA Astrophysics Data System (ADS)
Livers, A.; Han, L.; Delph, J. R.; White-Gaynor, A. L.; Petit, R.; Hole, J. A.; Stock, J. M.; Fuis, G. S.
2012-12-01
First-arrival refraction data were used to create a seismic velocity model of the upper crust across the actively rifting northern Imperial Valley and its margins. The densely sampled seismic refraction data were acquired by the Salton Seismic Imaging Project (SSIP) , which is investigating rift processes in the northern-most rift segment of the Gulf of California extensional province and earthquake hazards at the southern end of the San Andreas Fault system. A 95-km long seismic line was acquired across the northern Imperial Valley, through the Salton Sea geothermal field, parallel to the five Salton Butte volcanoes and perpendicular to the Brawley Seismic Zone and major strike-slip faults. Nineteen explosive shots were recorded with 100 m seismometer spacing across the valley and with 300-500 m spacing into the adjacent ranges. First-arrival travel times were picked from shot gathers along this line and a seismic velocity model was produced using tomographic inversion. Sedimentary basement and seismic basement in the valley are interpreted to be sediment metamorphosed by the very high heat flow. The velocity model shows that this basement to the west of the Brawley Seismic Zone is at ~4-km depth. The basement shallows to ~2-km depth in the active geothermal field and Salton Buttes volcanic field which locally coincide with the Brawley Seismic Zone. At the eastern edge of the geothermal field, the basement drops off again to ~3.5-km depth. The eastern edge of the valley appears to be fault bounded by the along-strike extension of the Sand Hills Fault, an inactive strike-slip fault. The seismic velocities to the east of the fault correspond to metamorphic rock of the Chocolate Mountains, different from the metamorphosed basement in the valley. The western edge of the valley appears to be fault bounded by the active Superstition Hills Fault. To the west of the valley, >4-km deep valley basement extends to the active Superstition Hills Fault. Basement then shallows westward towards exposures of granitic basement in the Superstition Mountains. The basin between the Superstition Mountains and Coyote Mountains is ~2 km deep.
Effect of urbanization on the water resources of eastern Chester County, Pennsylvania
Sloto, R.A.
1987-01-01
The effects of human activity on the water resources of a 207-square-mile area of eastern Chester County was evaluated. The most serious consequence of urbanization is the contamination of ground water by volatile organic compounds, which were detected in 39 percent of the 70 wells sampled. As many as nine compounds were found in one water sample, and the concentration of total volatile organic compounds was as high as 17,400 ug/L (micrograms per liter). In the Chester Valley, volatile organic compounds are moving down the hydraulic gradient caused by quarry dewatering. Movement through the quarries reduces concentrations of these compounds and removes most of them. Phenol was detected in 28 percent of 54 wells sampled, with concentrations up to 7 ug/L. Metals, except for iron and manganese, and other trace constituents generally are not a water-quality problem. However, ground water in an area in Chester Valley has been contaminated by concentrations of boron as high as 20,000 ug/L and lithium as high as 13,000 ug/L. The ground water discharges to Valley Creek, where concentrations of boron are as high as 130 ug/L and lithium as high as 800 ug/L. Concentrations of chloride as high as 2,100 mg/L (milligrams per liter) were found in a well at a former highway salt storage site. Wells completed in carbonate rock downgradient from the Pennsylvania Turnpike had chloride concentrations as high as 350 mg/L. The base-neutral organic compounds bis(2-ethylhexyl) phthalate, di-n-butyl phthalate, and 1,2-dichlorobenzene, and the pesticides alachlor, aldrian, diazanon, DDD, DDT, dieldrin, methyl parathion, picloram, and 2,4-D were detected in a few water samples in low concentrations, However, these organic compounds do not present a widespread water-quality problem. Neither acid organic compounds nor polychlorinated napthalenes (PCN) were detected in ground water. The growth of public water and sewer systems has resulted in a significant interbasin transfer of water. Estimates for 1984 range from a net loss of 630 million gallons in the Valley Creek basin to a net gain of 783 million gallons in the Chester Creek basin. The quantity of wastewater discharged from treatment plants generally correlates well with the altitude of the water table and poorly with water use or precipitation, indicating substantial ground-water infiltration. Estimated ground-water infiltration to the West Goshen treatment plant for 1980-84 was 0.8 cubic feet per square mile, or 10 percent of the long-term average flow of Chester Creek. Estimated ground-water infiltration to the Valley Forge sewer system was as high as 4.9 million gallons per day. Dewatering operations at two active quarries in Chester Valley have lowered water levels locally and increased the range of the fluctuation of the local water table. The spread of the cones of depression caused by quarry pumping is limited by geologic and hydrologic controls. Pumping of high-capacity wells in Chester Valley has caused small local cones of depression and may have caused some reaches of Valley Creek or its tributaries to lose water. One of the greatest effects of human activity on the surface-water system has been the accumulation of organic compounds, particularly PCB and pesticides, on stream-bottom material. PCB, DDE, and dieldrin were found in bottom material from all eight streams sampled. Land-use changes in 10 selected subbasins were quantified and related to stream-benthic invertebrate diversity index. from 1970-80, the diversity index increased at all sites. Subbasins that had a greater change in land use had a greater increase in diversity index. The increase may be due to the banning of certain pesticides such as DDT, a decreasing use of pesticides in urbanizing subbasins, or flushing or burial of older pesticide-contaminated sediment.
A regional soil and sediment geochemical study in northern California
Goldhaber, M.B.; Morrison, J.M.; Holloway, J.M.; Wanty, R.B.; Helsel, D.R.; Smith, D.B.
2009-01-01
Regional-scale variations in soil geochemistry were investigated in a 20,000-km2 study area in northern California that includes the western slope of the Sierra Nevada, the southern Sacramento Valley and the northern Coast Ranges. Over 1300 archival soil samples collected from the late 1970s to 1980 in El Dorado, Placer, Sutter, Sacramento, Yolo and Solano counties were analyzed for 42 elements by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry following a near-total dissolution. These data were supplemented by analysis of more than 500 stream-sediment samples from higher elevations in the Sierra Nevada from the same study site. The relatively high-density data (1 sample per 15 km2 for much of the study area) allows the delineation of regional geochemical patterns and the identification of processes that produced these patterns. The geochemical results segregate broadly into distinct element groupings whose distribution reflects the interplay of geologic, hydrologic, geomorphic and anthropogenic factors. One such group includes elements associated with mafic and ultramafic rocks including Cr, Ni, V, Co, Cu and Mg. Using Cr as an example, elevated concentrations occur in soils overlying ultramafic rocks in the foothills of the Sierra Nevada (median Cr = 160 mg/kg) as well as in the northern Coast Ranges. Low concentrations of these elements occur in soils located further upslope in the Sierra Nevada overlying Tertiary volcanic, metasedimentary and plutonic rocks (granodiorite and diorite). Eastern Sacramento Valley soil samples, defined as those located east of the Sacramento River, are lower in Cr (median Cr = 84 mg/kg), and are systematically lower in this suite compared to soils from the west side of the Sacramento Valley (median Cr = 130 mg/kg). A second group of elements showing a coherent pattern, including Ca, K, Sr and REE, is derived from relatively silicic rocks types. This group occurs at elevated concentrations in soils overlying volcanic and plutonic rocks at higher elevations in the Sierras (e.g. median La = 28 mg/kg) and the east side of the Sacramento Valley (median 20 mg/kg) compared to soils overlying ultramafic rocks in the Sierra Nevada foothills (median 15 mg/kg) and the western Sacramento Valley (median 14 mg/kg). The segregation of soil geochemistry into distinctive groupings across the Sacramento River arises from the former presence of a natural levee (now replaced by an artificial one) along the banks of the river. This levee has been a barrier to sediment transport. Sediment transport to the Valley by glacial outwash from higher elevations in the Sierra Nevada and, more recently, debris from placer Au mining has dominated sediment transport to the eastern Valley. High content of mafic elements (and low content of silicic elements) in surface soil in the west side of the valley is due to a combination of lack of silicic source rocks, transport of ultramafic rock material from the Coast Ranges, and input of sediment from the late Mesozoic Great Valley Group, which is itself enriched in mafic elements. A third group of elements (Zn, Cd, As and Cu) reflect the impact of mining activity. Soil with elevated content of these elements occurs along the Sacramento River in both levee and adjacent flood basin settings. It is interpreted that transport of sediment down the Sacramento River from massive sulfide mines in the Klamath Mountains to the north has caused this pattern. The Pb, and to some extent Zn, distribution patterns are strongly impacted by anthropogenic inputs. Elevated Pb content is localized in major cites and along major highways due to inputs from leaded gasoline. Zinc has a similar distribution pattern but the source is tire wear.
Geology and energy resources of the Sand Butte Rim NW Quadrangle, Sweetwater County, Wyoming
Roehler, Henry W.
1979-01-01
The Sand Butte Rim NW 71-minute quadrangle occupies 56 square miles of an arid, windy, sparsely vegetated area of ridges and valleys on the east flank of the Rock Springs uplift in southwest Wyoming. The area is underlain by a succession of sedimentary rocks, about 20,000 feet thick, that includes 28 formations ranging in age from Cambrian to Tertiary. Upper Cretaceous and lower Tertiary formations crop out and dip 3?-6? southeast. They are unfaulted and generally homoclinal, but a minor anticlinal nose is present. Older rocks in the subsurface are faulted and folded. Coal resources are estimated to be nearly I billion short tons of subbituminous coal, in beds more than 2.5 feet thick, under less than 3,000 feet of overburden, in the Fort Union Formation of Paleocene age and the Lance and Almond Formations of Cretaceous age.
Non-double-couple mechanisms of microearthquakes induced by hydraulic fracturing
Sileny, J.; Hill, D.P.; Eisner, Leo; Cornet, F.H.
2009-01-01
We have inverted polarity and amplitude information of representative microearthquakes to investigate source mechanisms of seismicity induced by hydraulic fracturing in the Carthage Cotton Valley, east Texas, gas field. With vertical arrays of four and eight three-component geophones in two monitoring wells, respectively, we were able to reliably determine source mechanisms of the strongest events with the best signal-to-noise ratio. Our analysis indicates predominantly non-double-couple source mechanisms with positive volumetric component consistent with opening cracks oriented close to expected hydraulic fracture orientation. Our observations suggest the induced events are directly the result of opening cracks by fluid injection, in contrast to many previous studies where the seismicity is interpreted to be primarily shearing caused by pore pressure diffusion into the surrounding rock or associated with shear stresses created at the hydraulic fracture tip. Copyright 2009 by the American Geophysical Union.
Paleomagnetic reorientation of San Andreas Fault Observatory at Depth (SAFOD) core
Pares, J.M.; Schleicher, A.M.; van der Pluijm, B.A.; Hickman, S.
2008-01-01
We present a protocol for using paleomagnetic analysis to determine the absolute orientation of core recovered from the SAFOD borehole. Our approach is based on determining the direction of the primary remanent magnetization of a spot core recovered from the Great Valley Sequence during SAFOD Phase 2 and comparing its direction to the expected reference field direction for the Late Cretaceous in North America. Both thermal and alternating field demagnetization provide equally resolved magnetization, possibly residing in magnetite, that allow reorientation. Because compositionally similar siltstones and fine-grained sandstones were encountered in the San Andreas Fault Zone during Stage 2 rotary drilling, we expect that paleomagnetic reorientation will yield reliable core orientations for continuous core acquired from directly within and adjacent to the San Andreas Fault during SAFOD Phase 3, which will be key to interpretation of spatial properties of these rocks. Copyright 2008 by the American Geophysical Union.
Preliminary Results from VOC measurements in the Lower Fraser Valley in July/Aug 2012
NASA Astrophysics Data System (ADS)
Schiller, C. L.; Jones, K.; Vingarzan, R.; Leaitch, R.; Macdonald, A.; Osthoff, H. D.; Reid, K.
2012-12-01
In July/August 2012, a pilot study looking at the effect of ClNO2 production on the ozone concentrations in the lower Fraser valley near Abbotsford, BC was conducted. The lower Fraser valley in British Columbia Canada has some of the highest ozone concentrations and visibility issues in Canada. Abbotsford is located approximately 80 kms east of Vancouver, BC and approximately 30 kms from the ocean. The site was located in a largely agricultural area with fruit farms (raspberries and blueberries) and poultry barns predominating. During the study biogenic and anthropogenic VOCs were measured in situ using a GCMS/FID with hourly samples. Particle composition was measured using an ACSM and size distribution using an SMPS. Preliminary results from the study will be discussed.
Effects of Climate and Social Change on Pasture Productivity and Area in the Alay Valley, Kyrgyzstan
NASA Astrophysics Data System (ADS)
Zhang, L.; Smithwick, E. A. H.
2017-12-01
The high elevation Alay Valley, located in the central Asian country of Kyrgyzstan, has experienced substantial socio-political and environmental changes in recent decades, resulting from the collapse of the Soviet Union and an increase in average annual temperature from 1.8 C to 2.7 C between 1990 and 2014. However, the consequences of these changes on pastureland productivity and area has not been previously assessed, despite the critical cultural and economic importance of pasturelands for sustaining livelihoods in this region. We assessed spatial and temporal patterns of soil moisture, pasture productivity and pasture area in the Alay Valley. Supervised classification was performed on Landsat imagery over the study region to distinguish pastures and agricultural land in order to relate changes in soil moisture to specific land classes. Root Zone Soil Moisture (RZSM) was estimated between May 2015 and June 2017 from Soil Moisture Active Passive L4 RZSM product. Average monthly NDVI for 2016 was calculated to obtain seasonal patterns in productivity of the pasturelands in the region. Results show that annual RZSM trends closely matched those of precipitation, as RZSM peaks during May (the wettest month) and decreases during the dry summer. The NDVI trend is also notable as it peaks very early in June before declining due to limited precipitation and grazing practices. There has been a sharp increase in pasturelands encompassing the bank of the Kyzyl Suu river from 1993 to 2016. Likely due to turmoil from collapse of the USSR, the area of pasturelands decreased slightly from 59.98 to 55.99 km^2 from 1993-1994, corresponding with a decline in livestock count and GDP per capita. The area of pasturelands has since recovered and is hovering around 104.47 - 107.95 km^2 between 2009-2016. Overall results highlight both sensitivity and resilience of high elevation pasture to coupled socio-environmental drivers.
Hydrology and simulation of ground-water flow in Juab Valley, Juab County, Utah.
Thiros, Susan A.; Stolp, Bernard J.; Hadley, Heidi K.; Steiger, Judy I.
1996-01-01
Plans to import water to Juab Valley, Utah, primarily for irrigation, are part of the Central Utah Project. A better understanding of the hydrology of the valley is needed to help manage the water resources and to develop conjunctive-use plans.The saturated unconsolidated basin-fill deposits form the ground-water system in Juab Valley. Recharge is by seepage from streams, unconsumed irrigation water, and distribution systems; infiltration of precipitation; and subsurface inflow from consolidated rocks that surround the valley. Discharge is by wells, springs, seeps, evapotranspiration, and subsurface outflow to consolidated rocks. Ground-water pumpage is used to supplement surface water for irrigation in most of the valley and has altered the direction of groundwater flow from that of pre-ground-water development time in areas near and in Nephi and Levan.Greater-than-average precipitation during 1980-87 corresponds with a rise in water levels measured in most wells in the valley and the highest water level measured in some wells. Less-than average precipitation during 1988-91 corresponds with a decline in water levels measured during 1988-93 in most wells. Geochemical analyses indicate that the sources of dissolved ions in water sampled from the southern part of the valley are the Arapien Shale, evaporite deposits that occur in the unconsolidated basin-fill deposits, and possibly residual sea water that has undergone evaporation in unconsolidated basin-fill deposits in selected areas. Water discharging from a spring at Burriston Ponds is a mixture of about 70 percent ground water from a hypothesized flow path that extends downgradient from where Salt Creek enters Juab Valley and 30 percent from a hypothesized flow path from the base of the southern Wasatch Range.The ground-water system of Juab Valley was simulated by using the U.S. Geological Survey modular, three-dimensional, finite-difference, ground-water flow model. The numerical model was calibrated to simulate the steady-state conditions of 1949, multi-year transient-state conditions during 1949-92, and seasonal transient-state conditions during 1992-94. Calibration parameters were adjusted until model-computed water levels reasonably matched measured water levels. Parameters important to the calibration process include horizontal hydraulic conductivity, transmissivity, and the spatial distribution and amount of recharge from subsurface inflow and seepage from ephemeral streams to the east side of Juab Valley.
Agricultural Influences on Cache Valley, Utah Air Quality During a Wintertime Inversion Episode
NASA Astrophysics Data System (ADS)
Silva, P. J.
2017-12-01
Several of northern Utah's intermountain valleys are classified as non-attainment for fine particulate matter. Past data indicate that ammonium nitrate is the major contributor to fine particles and that the gas phase ammonia concentrations are among the highest in the United States. During the 2017 Utah Winter Fine Particulate Study, USDA brought a suite of online and real-time measurement methods to sample particulate matter and potential gaseous precursors from agricultural emissions in the Cache Valley. Instruments were co-located at the State of Utah monitoring site in Smithfield, Utah from January 21st through February 12th, 2017. A Scanning mobility particle sizer (SMPS) and aerodynamic particle sizer (APS) acquired size distributions of particles from 10 nm - 10 μm in 5-min intervals. A URG ambient ion monitor (AIM) gave hourly concentrations for gas and particulate ions and a Chromatotec Trsmedor gas chromatograph obtained 10 minute measurements of gaseous sulfur species. High ammonia concentrations were detected at the Smithfield site with concentrations above 100 ppb at times, indicating a significant influence from agriculture at the sampling site. Ammonia is not the only agricultural emission elevated in Cache Valley during winter, as reduced sulfur gas concentrations of up to 20 ppb were also detected. Dimethylsulfide was the major sulfur-containing gaseous species. Analysis indicates that particle growth and particle nucleation events were both observed by the SMPS. Relationships between gas and particulate concentrations and correlations between the two will be discussed.
Dellagi, Koussay; Salez, Nicolas; Maquart, Marianne; Larrieu, Sophie; Yssouf, Amina; Silaï, Rahamatou; Leparc-Goffart, Isabelle; Tortosa, Pablo; de Lamballerie, Xavier
2016-01-01
A cross sectional serological survey of arboviral infections in humans was conducted on the three islands of the Union of Comoros, Indian Ocean, in order to test a previously suggested contrasted exposure of the three neighboring islands to arthropod-borne epidemics. Four hundred human sera were collected on Ngazidja (Grande Comore), Mwali (Mohéli) and Ndzouani (Anjouan), and were tested by ELISA for IgM and/or IgG antibodies to Dengue (DENV), Chikungunya (CHIKV), Rift Valley fever (RVFV), West Nile (WNV), Tick borne encephalitis (TBEV) and Yellow fever (YFV) viruses and for neutralizing antibodies to DENV serotypes 1–4. Very few sera were positive for IgM antibodies to the tested viruses indicating that the sero-survey was performed during an inter epidemic phase for the investigated arbovirus infections, except for RVF which showed evidence of recent infections on all three islands. IgG reactivity with at least one arbovirus was observed in almost 85% of tested sera, with seropositivity rates increasing with age, indicative of an intense and long lasting exposure of the Comorian population to arboviral risk. Interestingly, the positivity rates for IgG antibodies to DENV and CHIKV were significantly higher on Ngazidja, confirming the previously suggested prominent exposure of this island to these arboviruses, while serological traces of WNV infection were detected most frequently on Mwali suggesting some transmission specificities associated with this island only. The study provides the first evidence for circulation of RVFV in human populations from the Union of Comoros and further suggests that the virus is currently circulating on the three islands in an inconspicuous manner. This study supports contrasted exposure of the islands of the Comoros archipelago to arboviral infections. The observation is discussed in terms of ecological factors that may affect the abundance and distribution of vector populations on the three islands as well as concurring anthropogenic factors that may impact arbovirus transmission in this diverse island ecosystem. PMID:27977670
The Physics and Chemistry of carbides, Nitrides and Borides. Volume 185
1990-01-01
and C-B-C chains [15,17]. Clearly, the use of boron-rich solids as electronic materials will place new demands on the quality of materials. In this...first heated in a pyrolytic boron nitride (PBN) crucible ( Union Carbide Corp.) under high vacuum (< 50 mTorr) to 1900°C. This removed surface...contamination of the sample. The powders were loaded into a graphite die with a high-purity BN die liner ( Union Carbide Grade HBC) with inner diameter of 3/8
Detection of airborne genetically modified maize pollen by real-time PCR.
Folloni, Silvia; Kagkli, Dafni-Maria; Rajcevic, Bojan; Guimarães, Nilson C C; Van Droogenbroeck, Bart; Valicente, Fernando H; Van den Eede, Guy; Van den Bulcke, Marc
2012-09-01
The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this 'GM pollen monitoring by bioaerosol sampling and PCR screening' approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves. © 2012 Blackwell Publishing Ltd.
Union Army Veterans, All Grown Up
Costa, Dora L.; DeSomer, Heather; Hanss, Eric; Roudiez, Christopher; Wilson, Sven E.; Yetter, Noelle
2016-01-01
This paper overviews the research opportunities made possible by a NIA-funded program project, Early Indicators, Intergenerational Processes, and Aging. Data collection began almost three decades ago on 40,000 soldiers from the Union Army in the US Civil War. The sample contains extensive demographic, economic, and medical data from childhood to death. In recent years, a large sample of African-American soldiers and an oversampling of soldiers from major US cities have been added. Hundreds of historical maps containing public health data have been geocoded to place soldiers and their family members in a geospatial context. With newly granted funding, thousands of veterans will be linked to the demographic information available from the census and vital records of their children. PMID:28690347
James, Katherine A; Meliker, Jaymie R; Buttenfield, Barbara E; Byers, Tim; Zerbe, Gary O; Hokanson, John E; Marshall, Julie A
2014-08-01
Consumption of inorganic arsenic in drinking water at high levels has been associated with chronic diseases. Risk is less clear at lower levels of arsenic, in part due to difficulties in estimating exposure. Herein we characterize spatial and temporal variability of arsenic concentrations and develop models for predicting aquifer arsenic concentrations in the San Luis Valley, Colorado, an area of moderately elevated arsenic in groundwater. This study included historical water samples with total arsenic concentrations from 595 unique well locations. A longitudinal analysis established temporal stability in arsenic levels in individual wells. The mean arsenic levels for a random sample of 535 wells were incorporated into five kriging models to predict groundwater arsenic concentrations at any point in time. A separate validation dataset (n = 60 wells) was used to identify the model with strongest predictability. Findings indicate that arsenic concentrations are temporally stable (r = 0.88; 95 % CI 0.83-0.92 for samples collected from the same well 15-25 years apart) and the spatial model created using ordinary kriging best predicted arsenic concentrations (ρ = 0.72 between predicted and observed validation data). These findings illustrate the value of geostatistical modeling of arsenic and suggest the San Luis Valley is a good region for conducting epidemiologic studies of groundwater metals because of the ability to accurately predict variation in groundwater arsenic concentrations.
Anderholm, Scott K.
2002-01-01
As part of the National Water-Quality Assessment Program, surface-water and ground-water samples were collected in 1994 and 1995 for analysis of common constituents, nutrients, dissolved organic carbon, trace elements, radioactivity, volatile organic compounds, and pesticides to characterize surface- water quality and shallow ground-water quality and to determine factors affecting water quality in the Rincon Valley, south-central New Mexico. Samples of surface water were collected from three sites on the Rio Grande and from sites on three agricultural drains in the Rincon Valley in January 1994 and 1995, April 1994, and October 1994. Ground-water samples were collected in late April and early May 1994 from 30 shallow wells that were installed during the investigation. Dissolved-solids concentrations in surface water ranged from 434 to 1,510 milligrams per liter (mg/L). Dissolved-solids concentrations were smallest in water from the Rio Grande below Caballo Dam and largest in the drains. Nitrite plus nitrate concentrations ranged from less than 0.05 to 3.3 mg/L as nitrogen, and ammonia concentrations ranged from less than 0.015 to 0.33 mg/L as nitrogen in surface-water samples. Trace-element concentrations in surface water were significantly smaller than the acute-fisheries standards. One or more pesticides were detected in 34 of 37 surface-water samples. DCPA (dacthal) and metolachlor were the most commonly detected pesticides. No standards have been established for the pesticides analyzed for in this study. Dissolved-solids concentrations in shallow ground water ranged from 481 to 3,630 mg/L. All but 2 of 30 samples exceeded the secondary maximum contaminant level for dissolved solids of 500 mg/L. Water from about 73 percent of the wells sampled exceeded the secondary maximum contaminant level of 250 mg/L for sulfate, and water from about 7 percent of the wells sampled exceeded the secondary maximum contaminant level of 250 mg/L for chloride. Nitrite plus nitrate concentrations ranged from less than 0.05 to 33 mg/L as nitrogen in shallow ground water. Water from about 17 percent of the well samples exceeded the maximum contaminant level of 10 mg/L as nitrogen for nitrite plus nitrate. Trace-element concentrations in shallow ground water generally were small (1 to 10 micrograms per liter). The proposed maximum contaminant level of 20 micrograms per liter for uranium was exceeded in about 13 percent of the samples. The secondary maximum contaminant level of 300 micrograms per liter for iron was exceeded in about 17 percent of the samples and of 50 micrograms per liter for manganese was exceeded in about 83 percent of the samples. Samples from about 23 percent of the wells exceeded the maximum contaminant level of 15 picocuries per liter for gross alpha activity. One or more pesticides were detected in water from 12 of 30 wells sampled. The pesticides or pesticide metabolites diazinon, metolachlor, napropamide, p,p'-DDE, and prometon were detected in one or more samples. Metolachlor and prometon were the most commonly detected pesticides. Health advisories for the pesticides detected in shallow ground water (no maximum contaminant levels have been established for the pesticides detected) are 10 to 300 times larger than the concentrations detected. Infiltration, evaporation, and transpiration of irrigation water are important factors affecting the concentrations of common constituents in shallow ground water in the Rincon Valley. Dissolution and precipitation of minerals and mixing of shallow ground water and inflow of ground water from adjacent areas also affect the composition of shallow ground water and water in the drains. Relatively large nitrite plus nitrate concentrations in several shallow ground-water samples indicate leaching of fertilizers in some areas of th
NASA Astrophysics Data System (ADS)
Howard, A. J.; Coulthard, T. J.; Knight, D.
2017-09-01
The exploitation of river systems for power and navigation has commonly been achieved through the installation of a variety of in-channel obstacles of which weirs in Britain are amongst the most common. In the UK, the historic value of many of these features is recognised by planning designations and protection more commonly associated with historic buildings and other major monuments. Their construction, particularly in the north and west of Britain, has often been associated with industries such as textiles, chemicals, and mining, which have polluted waterways with heavy metals and other contaminants. The construction of weirs altered local channel gradients resulting in sedimentation upstream with the potential as well for elevated levels of contamination in sediments deposited there. For centuries these weirs have remained largely undisturbed, but as a result of the growth in hydropower and the drive to improve water quality under the European Union's Water Framework Directive, these structures are under increasing pressure to be modified or removed altogether. At present, weir modifications appear to be considered largely on an individual basis, with little focus on the wider impacts this might have on valley floor environments. Using a numerical modelling approach, this paper simulates the removal of major weirs along a 24-km stretch of the river Derwent, Derbyshire, UK, designated as a UNESCO World Heritage Site. The results suggest that although removal would not result in significant changes to the valley morphology, localised erosion would occur upstream of structures as the river readjusts its base level to new boundary conditions. Modelling indicates that sediment would also be evacuated away from the study area. In the context of the Derwent valley, this raises the potential for the remobilisation of contaminants (legacy sediments) within the wider floodplain system, which could have detrimental, long-term health and environmental implications for the river system. Worldwide, rivers have a common association with industry - being the focus of settlement and development since the earliest civilisations with channel engineering a common practice. Therefore, the conceptual issues raised by this study have global resonance and are particularly important where heritage protection is less robust and structures can be removed with little consideration of the environmental consequences.
NASA Astrophysics Data System (ADS)
Valla, Pierre; Rahn, Meinert; Shuster, David; van der Beek, Peter
2015-04-01
Neogene exhumation of the European Alps is understood as the interplay between tectonics and climatic-induced erosion. While the former has been influenced by a decrease in plate convergence, the latter has been suggested to be affected by climatic variation and the onset of Plio-Quaternary glaciations, leading to relief amplification. However, even though geomorphologic and sedimentologic studies both suggest topographic relief change and transition from fluvial to oscillations between glacial/fluvial conditions, precise quantification on both the timing and magnitude of this transition are yet sparse. Our study focuses on the upper Rhône valley (Swiss Central Alps) within the Visp-Brig area (Aar massif). This area encompasses some of the most spectacular reliefs within the Alps with several nearby summits around or above 4000 m crosscut by the glacially overdeepened Rhône valley. It also shows among the highest late Neogene exhumation rates within the Western-Central European Alps, influenced by tectonic activity along the major Simplon-Rhône extensional fault system. Moreover, the upper Rhône valley has experienced enhanced glacial erosion associated with strong relief development during the Pliocene-Quaternary period. Finally, structural inheritance, late-stage tectonics and rapid exhumation may have promoted recent hydrothermal activity in this region, although timing of its onset and its precise causes remain poorly understood. We investigated the late-stage cooling history by using different low-temperature thermochronometers along a pseudo-vertical bedrock profile (elevation between 600 and 2900 m) and additional samples from an on-site 500-m geothermal well, resulting in a total elevation difference of nearly 3 km. Apatite fission-track (AFT) ages and track-length data have been added to previously published and new apatite (U-Th-Sm)/He (AHe) and 4He/3He data. Our results confirm high-exhumation rates (0.6 to 0.9 km/Myr) within late-Cenozoic to Pliocene times. Combined with AFT data from the literature, our age pattern reveals no exhumation difference across the Simplon fault system during the last 6-8 Ma, suggesting only strike-slip detachment activity of the structure during that period. Thermal modelling using HeFTy confirms rapid exhumation and evidences a late-stage cooling contrast between high-elevation and valley-bottom/geothermal well samples, in agreement with previous 4He/3He data. This late-stage exhumation is associated to the onset of major Alpine glaciation triggering the Rhône valley carving at ~1 Ma. Apatite track length measurements suggest that the well samples have been affected by recent hydrothermal activity. This agrees well with the present-day observation of high geothermal activity below the Rhône valley floor, whose origin has been primarily linked to structural inheritance (Simplon-Rhône extensional fault system). Our thermochronology data helps to put constrain on the onset timing of this geothermal activity, which we propose to be concordant with the onset of major alpine glaciations, glacial erosion and bedrock-fracture development promoting localized fluid circulation and hydrothermal activity below the Rhône valley floor.
Virgin Valley opal district, Humboldt County, Nevada
Staatz, Mortimer Hay; Bauer, Herman L.
1951-01-01
The Virgin Valley opal district, Humboldt County, Nevada, is near the Oregon-Nevada border in the Sheldon Game Refuge. Nineteen claims owned by Jack and Toni Crane were examined, sampled, and tested radiometrically for uranium. Numerous discontinuous layers of opal are interbedded with a gently-dipping series of vitric tuff and ash which is at least 300 ft thick. The tuff and ash are capped by a dark, vesicular basalt in the eastern part of the area and by a thin layer of terrace qravels in the area along the west side of Virgin Valley. Silicification of the ash and tuff has produced a rock that ranges from partly opalized rock that resembles silicified shale to completely altered rock that is entirely translucent, and consists of massive, brown and pale-green opal. Carnotite, the only identified uranium mineral, occurs as fracture coatings or fine layers in the opal; in places, no uranium minerals are visible in the radioactive opal. The opal layers are irregular in extent and thickness. The exposed length of the layers ranges from 8 to 1, 200 ft or more, and the thickness of the layers ranges from 0. 1 to 3. 9 ft. The uranium content of each opal layer, and of different parts of the same layer, differs widely. On the east side of Virgin Valley four of the seven observed opal layers, nos. 3, 4, 5, and 7, are more radioactive than the average; and the uranium content ranges from 0. 002 to 0. 12 percent. Two samples, taken 5 ft apart across opal layer no. 7, contained 0. 003 and 0. -049 percent uranium. On the west side of the valley only four of the fifteen observed opal layers, nos; 9, , 10, 14, and 15, are more radioactive than the average; and the uranium content ranges from 0. 004 to 0. 047 percent. Material of the highest grade was found in a small discontinuous layer of pale-green opal (no. 4) on the east side of Virgin Valley. The grade of this layer ranged from 0. 027 to 0. 12 percent uranium.
Wilberg, D.E.; Stolp, B.J.
1985-01-01
Hydrologic, geologic, and partial water quality data were collected at 90 selected springs in west-central Utah, and chemical analyses performed on water samples from 62 of the springs. Descriptions of the physiographic and geologic conditions, climate, and vegetation patterns for the study area are included. Allowable limits of certain chemical constituents in water for human and livestock consumption are included with the water quality data. Three classifications of springs were established based on physical characteristics of the springs, and chemical composition of the springflow: (1) mountain springs; (2) non-thermal valley springs, and (3) thermal valley springs. Mountain springs are in and near recharge areas, have seasonal variations of discharge and temperature, typically discharge from extrusive and metamorphic geohydrologic units, and generally discharge freshwater. Non-thermal valley springs are peripheral to recharge areas, have seasonal variations of discharge and temperature, typically discharge from a variety of geohydrologic units, and have variable water composition. Thermal valley springs are near topographic low areas of valleys , and have little seasonal variation of discharge or temperature. They typically discharge from unconsolidated deposits (but the discharge probably has flowed through buried carbonate geohydrologic units). They also have a considerable range of water composition that reflects the relative complexity of the groundwater system. (Author 's abstract)
NASA Astrophysics Data System (ADS)
Kirpes, R.; Blake, D. R.; Marrero, J.
2013-12-01
Following the Montreal Protocol of 1987 calling for the phase-out of CFCs and other ozone depleting substances, HCFCs and HFCs were introduced as alternatives despite still being greenhouse gases with high global warming potentials. In this study, whole air samples were collected during four research flights over Southern California aboard the NASA DC-8 Airborne Science Laboratory as part of the NASA Student Airborne Science Program. These samples were then analyzed by gas chromatography using a suite of detectors for many compounds, including HFC-134a, HCFC-22, and HFC-152a. HCFC-22 is primarily used as a refrigerant, while HFC-134a and HFC-152a are also used as aerosol propellants and foam blowing agents. High concentrations of these three compounds were observed for samples taken at low altitudes over urban areas around Los Angeles and San Bernardino. Exceptionally high concentrations were seen for all three compounds in samples taken near the Ontario and San Bernardino airports. Concentrations of HFC-134a, HCFC-22, and HFC-152a were enhanced above background levels near other airports sampled in the Los Angeles Basin and San Bernardino Valley. It is clear that concentrations of these three gases are higher in the San Bernardino Valley than in the Los Angeles Basin, and locations with exceptionally high concentrations were investigated to identify potential point sources. Concentrations of these three compounds were also compared to data from past SARP missions and data collected at Trinidad Head, California since 2005 as part of the AGAGE network. Comparison of the average values for each of these campaigns reveal that the background concentrations of HFC-134a, HCFC-22, and HFC-152a are all increasing with a strong linear trend in Southern California.
Episodic acidification and changes in fish diversity in Pennsylvania headwater streams
Heard, R.M.; Sharpe, W.E.; Carline, R.F.; Kimmel, William G.
1997-01-01
Current water chemistry and fish communities in 70 Pennsylvania streams were compared with historical records to determine whether fish species richness had declined and, if so, the possible role of acidification. First-, second-, and third-order streams were selected, and stream sites sampled during the 1961-1971 survey were resampled during May and June 1994 in the Appalachian Plateaus province and during June 1995 in the Valley and Ridge province. Stream-flow was measured and a habitat assessment was completed at each site. Dominant bedrock types influencing the stream sampling site were determined for the Appalachian Plateaus streams. Episodic water chemistry was collected for 39 of the 50 Appalachian Plateaus streams and 14 of the 20 Valley and Ridge streams during the winter and spring of 1996. Thirty-eight (76%) streams of the Appalachian Plateaus province and 13 (65%) streams in the Valley and Ridge province had a loss of fish species since the 1961-1971 sampling period. Habitat scores were not related to losses of fish species. Of the 53 streams sampled during runoff episodes 22 (42%) increased in total dissolved aluminum by more than 50 ??g/L, and 31 (58%) streams decreased in pH by 0.5 units or more. Minnows (Cyprinidae) and darters (Percidae) are sensitive to acidity and were the species most often lost. Streams draining watersheds of the Appalachian Plateaus province dominated by Pottsville bedrock had more acidic water quality during base flow and storm flow sampling periods than streams dominated by Pocono bedrock. The results of this study indicate that many Pennsylvania streams have undergone an alarming reduction in fish diversity during the past 25-34 years. In many of these streams the loss in fish diversity may be attributed to episodic acidification.
Ghaju Shrestha, Rajani; Tanaka, Yasuhiro; Malla, Bikash; Bhandari, Dinesh; Tandukar, Sarmila; Inoue, Daisuke; Sei, Kazunari; Sherchand, Jeevan B; Haramoto, Eiji
2017-12-01
Bacteriological analysis of drinking water leads to detection of only conventional fecal indicator bacteria. This study aimed to explore and characterize bacterial diversity, to understand the extent of pathogenic bacterial contamination, and to examine the relationship between pathogenic bacteria and fecal indicator bacteria in different water sources in the Kathmandu Valley, Nepal. Sixteen water samples were collected from shallow dug wells (n=12), a deep tube well (n=1), a spring (n=1), and rivers (n=2) in September 2014 for 16S rRNA gene next-generation sequencing. A total of 525 genera were identified, of which 81 genera were classified as possible pathogenic bacteria. Acinetobacter, Arcobacter, and Clostridium were detected with a relatively higher abundance (>0.1% of total bacterial genes) in 16, 13, and 5 of the 16 samples, respectively, and the highest abundance ratio of Acinetobacter (85.14%) was obtained in the deep tube well sample. Furthermore, the bla OXA23-like genes of Acinetobacter were detected using SYBR Green-based quantitative PCR in 13 (35%) of 37 water samples, including the 16 samples that were analyzed for next-generation sequencing, with concentrations ranging 5.3-7.5logcopies/100mL. There was no sufficient correlation found between fecal indicator bacteria, such as Escherichia coli and total coliforms, and potential pathogenic bacteria, as well as the bla OXA23-like gene of Acinetobacter. These results suggest the limitation of using conventional fecal indicator bacteria in evaluating the pathogenic bacteria contamination of different water sources in the Kathmandu Valley. Copyright © 2017 Elsevier B.V. All rights reserved.
Revisiting the Field Geology of Taurus-Littrow
NASA Technical Reports Server (NTRS)
Schmitt, H. H.; Petro, N. E.; Wells, R. A.; Robinson, M. S.; Weiss, B. P.; Mercer, C. M.
2016-01-01
Integration of Apollo 17 field observations and photographs, sample investigations, Lunar Reconnaissance Orbiter Camera images, Chandrayaan-1 Moon Mineralogy Mapper (M(sup 3)) spectra, and Miniature Radio Frequency (Mini-RF) S-band radar images provides new insights into the geology of the valley of Taurus-Littrow on the Moon. Connecting the various remote observations to sample data enables a set of new conclusions to be drawn regarding the geological evolution of the valley. Structural considerations and published and recalculated Ar-40/Ar-39 analyses of samples from the North Massif and the Sculptured Hills indicate that the Crisium basin formed about 3.93 Ga; the Serenitatis basin about 3.82 Ga; and the Imbrium basin no earlier than 3.82 Ga and no later than the average of 3.72 Ga for 33 age dates from samples of the valley's mare basalts. Strong evidence continues to support the conclusion of others (Lucchitta, 1972; Spudis et al., 2011; Fassett et al., 2012) that the Sculptured Hills physiographic unit consists of Imbrium ejecta. Interpretation of M(sup 3) spectral data and Apollo 17 samples indicate that rock units of the Sculptured Hills consist of a largely coherent, Mg-suite pluton. LROC NAC stereo images and Mini-RF data indicate the presence of several exposed pyroclastic fissures across the Sculptured Hills. Rim boulders at Camelot Crater constitute nearly in situ wall rocks of that crater rather than ejecta and provide an opportunity for investigations of remanent magnetic field orientation at the time of the eruption of late mare basalt lavas in the valley. Paleomagnetic field orientation information also may be obtained relative to melt-breccia contacts in North Massif boulders that suggest original horizontal orientations. LROC images indicate the existence of two temporally separate light mantle avalanche deposits. The origin, potential flow mechanisms, and geology of the youngest avalanche from the South Massif have been clarified. The existence of two distinct light mantle avalanches raises doubt about the association of either light mantle avalanche with secondary impacts related to the Tycho impact event. Alternatively, the Lee-Lincoln thrust fault appears to have triggered the second light mantle avalanche between 70 and 110 Ma. A simple structural analysis shows that this thrust fault dips 20-25 degrees to the southwest where it crosses the North Massif and to the west where it crosses the valley floor. Mini-RF data reveal a line of reduced reflections roughly perpendicular to contours on the North Massif about 3 km to the east of the Lee-Lincoln fault. Although this line is possibly an older ancillary fault, LROC NAC stereo images indicate that it may be best explained as a pyroclastic fissure. A debris flow of dark, apparent pyroclastic ash lies below the southeast end of the potential fissure. Finally, young lunar impact glass sample 70019 has been precisely located within LROC NAC images and oriented for the first time using 60 mm (f.l.) sample documentation photographs. Sample 70019 can now be employed in lunar paleomagnetic field orientation studies.
Revisiting the field geology of Taurus-Littrow
NASA Astrophysics Data System (ADS)
Schmitt, H. H.; Petro, N. E.; Wells, R. A.; Robinson, M. S.; Weiss, B. P.; Mercer, C. M.
2017-12-01
Integration of Apollo 17 field observations and photographs, sample investigations, Lunar Reconnaissance Orbiter Camera images, Chandrayaan-1 Moon Mineralogy Mapper (M3) spectra, and Miniature Radio Frequency (Mini-RF) S-band radar images provides new insights into the geology of the valley of Taurus-Littrow on the Moon. Connecting the various remote observations to sample data enables a set of new conclusions to be drawn regarding the geological evolution of the valley. Structural considerations and published and recalculated 40Ar/39Ar analyses of samples from the North Massif and the Sculptured Hills indicate that the Crisium basin formed about 3.93 Ga; the Serenitatis basin about 3.82 Ga; and the Imbrium basin no earlier than 3.82 Ga and no later than the average of 3.72 Ga for 33 age dates from samples of the valley's mare basalts. Strong evidence continues to support the conclusion of others (Lucchitta, 1972; Spudis et al., 2011; Fassett et al., 2012) that the Sculptured Hills physiographic unit consists of Imbrium ejecta. Interpretation of M3 spectral data and Apollo 17 samples indicate that rock units of the Sculptured Hills consist of a largely coherent, Mg-suite pluton. LROC NAC stereo images and Mini-RF data indicate the presence of several exposed pyroclastic fissures across the Sculptured Hills. Rim boulders at Camelot Crater constitute nearly in situ wall rocks of that crater rather than ejecta and provide an opportunity for investigations of remanent magnetic field orientation at the time of the eruption of late mare basalt lavas in the valley. Paleomagnetic field orientation information also may be obtained relative to melt-breccia contacts in North Massif boulders that suggest original horizontal orientations. LROC images indicate the existence of two temporally separate light mantle avalanche deposits. The origin, potential flow mechanisms, and geology of the youngest avalanche from the South Massif have been clarified. The existence of two distinct light mantle avalanches raises doubt about the association of either light mantle avalanche with secondary impacts related to the Tycho impact event. Alternatively, the Lee-Lincoln thrust fault appears to have triggered the second light mantle avalanche between 70 and 110 Ma. A simple structural analysis shows that this thrust fault dips 20-25° to the southwest where it crosses the North Massif and to the west where it crosses the valley floor. Mini-RF data reveal a line of reduced reflections roughly perpendicular to contours on the North Massif about 3 km to the east of the Lee-Lincoln fault. Although this line is possibly an older ancillary fault, LROC NAC stereo images indicate that it may be best explained as a pyroclastic fissure. A debris flow of dark, apparent pyroclastic ash lies below the southeast end of the potential fissure. Finally, young lunar impact glass sample 70019 has been precisely located within LROC NAC images and oriented for the first time using 60 mm (f.l.) sample documentation photographs. Sample 70019 can now be employed in lunar paleomagnetic field orientation studies.
Dudeja, Divya; Bartarya, Sukesh Kumar; Biyani, A K
2011-10-01
The present study discusses ion sources and assesses the chemical quality of groundwater of Doon Valley in Outer Himalayan region for drinking and irrigational purposes. Valley is almost filled with Doon gravels that are main aquifers supplying water to its habitants. Recharged only by meteoric water, groundwater quality in these aquifers is controlled essentially by chemical processes occurring between water and lithology and locally altered by human activities. Seventy-six water samples were collected from dug wells, hand pumps and tube wells and were analysed for their major ion concentrations. The pH is varying from 5.6 to 7.4 and electrical conductivity from 71 to 951 μmho/cm. Groundwater of Doon valley is dominated by bicarbonate contributing 83% in anionic abundance while calcium and magnesium dominate in cationic concentrations with 88%. The seasonal and spatial variation in ionic concentration, in general, is related to discharge and lithology. The high ratio of (Ca + Mg)/(Na + K), i.e. 10, low ratio of (Na + K)/TZ+, i.e.0.2 and also the presence of carbonate lithology in the northern part of valley, is indicative of carbonate dissolution as the main controlling solute acquisition process in the valley. The low abundance of silica content and high HCO₃/H₄SiO₄ ratio also supports carbonate dissolution and less significant role of silicate weathering as the major source for dissolved ions in Doon Valley. The analytical results computed for various indices show that water is of fairly good quality, although, hard but have moderate dissolved solid content. It is free from sodium hazard lying in C₁-S₁ and C₂-S₁ class of USSL diagram and in general suitable for drinking and irrigation except few locations having slightly high salinity hazard.
NASA Astrophysics Data System (ADS)
Rao, K. Shankar; Eckman, Richard M.; Hosker, Rayford P., Jr.
1989-07-01
During the 1984 ASCOT field study in Brush Creek Valley, two perfluorocarbon tracers were released into the nocturnal drainage flow at two different heights. The resulting surface concentrations were sampled at 90 sites, and vertical concentration profiles at 11 sites. These detailed tracer measurements provide a valuable dataset for developing and testing models of pollutant transport and dispersion in valleys.In this paper, we present the results of Gaussian puff model simulations of the tracer releases in Brush Creek Valley. The model was modified to account for the restricted lateral dispersion in the valley, and for the gross elevation differences between the release site and the receptors. The variable wind fields needed to transport the puffs were obtained by interpolation between wind profiles measured using tethered balloons at five along-valley sites. Direct turbulence measurements were used to estimate diffusion. Subsidence in the valley flow was included for elevated releases.Two test simulations-covering different nights, tracers, and release heights-were performed. The predicted hourly concentrations were compared with observations at 51 ground-level locations. At most sites, the predicted and observed concentrations agree within a factor of 2 to 6. For the elevated release simulation, the observed mean concentration is 40 pL/L, the predicted mean is 21 pL/L, the correlation coefficient between the observed and predicted concentrations is 0.24, and the index of agreement is 0.46. For the surface release simulation, the observed mean is 85 pL/L, and the predicted mean is 73 pL/L. The correlation coefficient is 0.23, and the index of agreement is 0.42. The results suggest that this modified puff model can be used as a practical tool for simulating pollutant transport and dispersion in deep valleys.
NASA Astrophysics Data System (ADS)
Lopez, K. A.; Baron, D.; Guo, J.; Woolford, J. M.
2016-12-01
The early to middle Miocene Olcese Formation in the southern San Joaquin Valley of California consists of shallow marine shelf sands in its lower and upper parts, and non-marine, frequently pumiceous sands in its middle part, and varies in thickness up to 1800 ft. There is little known as to the origin, nature, quantity, and distribution of clay minerals throughout the formation. This study examined 95 sidewall core samples from three wells, as well as 388 cutting samples from four wells and 12 samples from 3 outcrops. Well samples were from depths between 1,800 and 4,000 ft. Qualitative and quantitative mineralogy including clay minerals of the sidewall samples and selected cutting samples was determined by powder X-ray diffraction (XRD). XRD analyses were supplemented by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) and petrographic microscopy of selected samples. The main minerals of bulk samples include composite clay, quartz, potassium feldspar/plagioclase, calcite, and clinoptilolite. Content of composite clay varies between 17% and 51%. The clay-size fraction is predominantly composed of smectite, illite, kaolinite and chlorite with smectite being the most abundant. Smectite and clinoptilolite may be the alteration products of deeper burial of volcanic materials. The formation permeability could be significantly lowered by these authigenic minerals.
Orlando, James L.; Jacobson, Lisa A.; Kuivila, Kathryn
2004-01-01
Field and laboratory studies were conducted to determine the effects of pesticide mixtures on Chinook salmon under various environmental conditions in surface waters of the northern Central Valley of California. This project was a collaborative effort between the U.S. Geological Survey (USGS) and the University of California. The project focused on understanding the environmental factors that influence the toxicity of pesticides to juvenile salmon and their prey. During the periods January through March 2001 and January through May 2002, water samples were collected at eight surface water sites in the northern Central Valley of California and analyzed by the USGS for dissolved pesticide and dissolved organic carbon concentrations. Water samples were also collected by the USGS at the same sites for aquatic toxicity testing by the Aquatic Toxicity Laboratory at the University of California Davis; however, presentation of the results of these toxicity tests is beyond the scope of this report. Samples were collected to characterize dissolved pesticide and dissolved organic carbon concentrations, and aquatic toxicity, associated with winter storm runoff concurrent with winter run Chinook salmon out-migration. Sites were selected that represented the primary habitat of juvenile Chinook salmon and included major tributaries within the Sacramento and San Joaquin River Basins and the Sacramento?San Joaquin Delta. Water samples were collected daily for a period of seven days during two winter storm events in each year. Additional samples were collected weekly during January through April or May in both years. Concentrations of 31 currently used pesticides were measured in filtered water samples using solid-phase extraction and gas chromatography-mass spectrometry at the U.S. Geological Survey's organic chemistry laboratory in Sacramento, California. Dissolved organic carbon concentrations were analyzed in filtered water samples using a Shimadzu TOC-5000A total organic carbon analyzer.
Magnetic properties of Apollo samples and implications for regolith formation
NASA Technical Reports Server (NTRS)
Pearce, G. W.; Strangway, D. W.; Gose, W. A.
1974-01-01
The magnetic properties of a number of Apollo 17 samples have been measured and confirm that regoliths of mare sites (Apollo 11, 12, 15 valley, and 17 valley) differ markedly from those of highland sites (Apollo 14, 16, and 17 massif) in the ratio of content of metallic to ferrous iron and in the grain size of metallic iron. The ratio of metallic to ferrous iron is correlated with mean particle size, a parameter representing maturity, for soils of Apollo 16 and roughly correlated with the age of the sites for soils of different sites. It is suggested that the ratio of metallic to ferrous iron may be an effective indicator of relative soil maturity for any one site and of the age of the soil material for any sites.
Garcia, A.F.; Mahan, S.A.
2009-01-01
Factors influencing sediment transport and storage within the 156??6 km2 drainage basin of Pancho Rico Creek (PRC), and sediment transport from the PRC drainage basin to its c. 11000 km2 mainstem drainage (Salinas River) are investigated. Numeric age estimates are determined by optically stimulated luminescence (OSL) dating on quartz grains from three sediment samples collected from a 'quaternary terrace a (Qta)' PRC terrace/PRC-tributary fan sequence, which consists dominantly of debris flow deposits overlying fluvial sediments. OSL dating results, morphometric analyses of topography, and field results indicate that the stormy climate of the Pleistocene-Holocene transition caused intense debris-flow erosion of PRC- tributary valleys. However, during that time, the PRC channel was backfilled by Qta sediment, which indicates that there was insufficient discharge in PRC to transport the sediment load produced by tributary-valley denudation. Locally, Salinas Valley alluvial stratigraphy lacks any record of hillslope erosion occurring during the Pleistocene-Holocene transition, in that the alluvial fan formed where PRC enters the Salinas Valley lacks lobes correlative to Qta. This indicates that sediment stripped from PRC tributaries was mostly trapped in Pancho Rico Valley despite the relatively moist climate of the Pleistocene-Holocene transition. Incision into Qta did not occur until PRC enlarged its drainage basin by c. 50% through capture of the upper part of San Lorenzo Creek, which occurred some time after the Pleistocene-Holocene transition. During the relatively dry Holocene, PRC incision through Qta and into bedrock, as well as delivery of sediment to the San Ardo Fan, were facilitated by the discharge increase associated with stream-capture. The influence of multiple mechanisms on sediment storage and transport in the Pancho Rico Valley-Salinas Valley system exemplifies the complexity that (in some instances) must be recognized in order to correctly interpret terrestrial sedimentary sequences in tectonically active areas. ?? 2009 John Wiley & Sons, Ltd.
Andrew Fowler
2015-05-01
Results for fluid rare earth element analyses from four Reykjanes peninsula high-temperature geothermal fields. Data for fluids from hydrothermal vents located 2400 m below sea level from Middle Valley on the Juan de Fuca Ridge are also included. Data have been corrected for flashing. Samples preconcentrated using a chelating resin with IDA functional group (InertSep ME-1). Analyzed using an Element magnetic sector inductively coupled plasma mass spectrometry (ICP-MS).
1991-02-01
analysis of water, soil, and/or sediment samples, are required. Careful documentation and quality control procedures in accordance with CERCLA/SARA...I III-1 I I Northern Piedmont * AI Southern Piedmont a’.3 Cahaba Valley... ...... Coosa ValleyI Fall Line Hills Aluvial Plain Black Prairie3 Cu enu e...no surface outlet; (b) A drainage basin or river basin; (c) A low area in the Earth’s crust, of tectonic origin, in which sediments have accumulated
Regmi, Ram Krishna; Mishra, Binaya Kumar; Masago, Yoshifumi; Luo, Pingping; Toyozumi-Kojima, Asako; Jalilov, Shokhrukh-Mirzo
2017-08-01
Human activities during recent decades have led to increased degradation of the river water environment in South Asia. This degradation has led to concerns for the populations of the major cities of Nepal, including those of the Kathmandu Valley. The deterioration of the rivers in the valley is directly linked to the prevalence of poor sanitary conditions, as well as the presence of industries that discharge their effluents into the river. This study aims to investigate the water quality aspect for the aquatic ecosystems and recreation of the major rivers in the Kathmandu Valley using the Canadian Council of Ministers of the Environment water quality index (CCME WQI). Ten physicochemical parameters were used to determine the CCME WQI at 20 different sampling locations. Analysis of the data indicated that the water quality in rural areas ranges from excellent to good, whereas in denser settlements and core urban areas, the water quality is poor. The study results are expected to provide policy-makers with valuable information related to the use of river water by local people in the study area.
Reif, Andrew G.; Sloto, Ronald A.
1997-01-01
The Schuylkill River flows through Valley Forge National Historical Park in Lower Providence and West Norriton Townships in Montgomery County, Pa. The concentration of selected metals, pesticides, semivolatile organic compounds, and total carbon in stream-bottom sediments from Valley Forge National Historical Park were determined for samples collected once at 12 sites in and around the Schuylkill River.Relatively low concentrations of arsenic, chromium, copper, and lead were detected in all samples. The concentrations of these metals are similar to concentrations in other stream-bottom sediment samples collected in the region. The concentrations of iron, manganese, and zinc were elevated in samples from four sites in the Schuylkill River, and the concentration of mercury was elevated in a sample from an impoundment along the river.The organophosphorus insecticide diazinon was detected in relatively low concentrations in half of the 12 samples analyzed. The organo-chlorine insecticide DDE was detected in all 12 samples analyzed; dieldrin was detected in 10 samples, chlordane, DDD, and DDT were detected in 9 samples, and heptachlor epoxide was detected in one sample. The concentrations of organo-chlorine and organophosphorus insecticides were relatively low and similar to concentrations in samples collected in the region.Detectable concentrations of 17 semivolatile organic compounds were measured in the 12 samples analyzed. The most commonly detected compounds were fluoranthene, phenanthrene, and pyrene. The maximum concentration detected was 4,800 micrograms per kilogram of phenanthrene. The highest concentrations of compounds were detected in Lamb Run, a small tributary to the Schuylkill River with headwaters in an industrial corporate center. The concentration of compounds in the Schuylkill River below Lamb Run is higher than the Schuylkill River above Lamb Run, indicating that sediment from Lamb Run is increasing the concentration of semivolatile organic compounds in sediment from the Schuylkill River. Concentrations of semivolatile organic compounds are lower in sediment from the Schuylkill River below Myer's Run than above Myer's Run because of the addition of relatively clean sediment from Myer's Run. Samples collected from the floodplain, impounding basin, and wetland along the Schuylkill River contained the lowest concen-trations of semivolatile organic compounds.Detectable concentrations of polychlorinated biphenyls (PCB's) were measured in 11 of the 12 samples analyzed. The maximum PCB concentration was 37 micrograms per kilogram. Sediment samples from Lamb Run contained the highest concentrations of semivolatile organic compounds and PCB's.
Rift Valley Fever Risk Map Model and Seroprevalence in Selected Wild Ungulates and Camels from Kenya
Ruder, Mark G.; Linthicum, Kenneth J.; Anyamba, Assaf; Small, Jennifer L.; Tucker, Compton J.; Ateya, Leonard O.; Oriko, Abuu A.; Gacheru, Stephen; Wilson, William C.
2013-01-01
Since the first isolation of Rift Valley fever virus (RVFV) in the 1930s, there have been multiple epizootics and epidemics in animals and humans in sub-Saharan Africa. Prospective climate-based models have recently been developed that flag areas at risk of RVFV transmission in endemic regions based on key environmental indicators that precede Rift Valley fever (RVF) epizootics and epidemics. Although the timing and locations of human case data from the 2006–2007 RVF outbreak in Kenya have been compared to risk zones flagged by the model, seroprevalence of RVF antibodies in wildlife has not yet been analyzed in light of temporal and spatial predictions of RVF activity. Primarily wild ungulate serum samples from periods before, during, and after the 2006–2007 RVF epizootic were analyzed for the presence of RVFV IgM and/or IgG antibody. Results show an increase in RVF seropositivity from samples collected in 2007 (31.8%), compared to antibody prevalence observed from 2000–2006 (3.3%). After the epizootic, average RVF seropositivity diminished to 5% in samples collected from 2008–2009. Overlaying maps of modeled RVF risk assessments with sampling locations indicated positive RVF serology in several species of wild ungulate in or near areas flagged as being at risk for RVF. Our results establish the need to continue and expand sero-surveillance of wildlife species Kenya and elsewhere in the Horn of Africa to further calibrate and improve the RVF risk model, and better understand the dynamics of RVFV transmission. PMID:23840512
Understanding erosion rates in the Himalayan orogen: A case study from the Arun Valley
NASA Astrophysics Data System (ADS)
Olen, Stephanie M.; Bookhagen, Bodo; Hoffmann, Bernd; Sachse, Dirk; Adhikari, D. P.; Strecker, Manfred R.
2015-10-01
Understanding the rates and pattern of erosion is a key aspect of deciphering the impacts of climate and tectonics on landscape evolution. Denudation rates derived from terrestrial cosmogenic nuclides (TCNs) are commonly used to quantify erosion and bridge tectonic (Myr) and climatic (up to several kiloyears) time scales. However, how the processes of erosion in active orogens are ultimately reflected in 10Be TCN samples remains a topic of discussion. We investigate this problem in the Arun Valley of eastern Nepal with 34 new 10Be-derived catchment-mean denudation rates. The Arun Valley is characterized by steep north-south gradients in topography and climate. Locally, denudation rates increase northward, from <0.2 mm yr-1 to ~1.5 mm yr-1 in tributary samples, while main stem samples appear to increase downstream from ~0.2 mm yr-1 at the border with Tibet to 0.91 mm yr-1 in the foreland. Denudation rates most strongly correlate with normalized channel steepness (R2 = 0.67), which has been commonly interpreted to indicate tectonic activity. Significant downstream decrease of 10Be concentration in the main stem Arun suggests that upstream sediment grains are fining to the point that they are operationally excluded from the processed sample. This results in 10Be concentrations and denudation rates that do not uniformly represent the upstream catchment area. We observe strong impacts on 10Be concentrations from local, nonfluvial geomorphic processes, such as glaciation and landsliding coinciding with areas of peak rainfall rates, pointing toward climatic modulation of predominantly tectonically driven denudation rates.
Rift Valley Fever Risk Map Model and Seroprevalence in Selected Wild Ungulates and Camels from Kenya
NASA Technical Reports Server (NTRS)
Britch, Seth C.; Binepal, Yatinder S.; Ruder, Mark G.; Kariithi, Henry M.; Linthicum, Kenneth J.; Anyamba, Assaf; Small, Jennifer L.; Tucker, Compton J.; Ateya, Leonard O.; Oriko, Abuu A.;
2013-01-01
Since the first isolation of Rift Valley fever virus (RVFV) in the 1930s, there have been multiple epizootics and epidemics in animals and humans in sub-Saharan Africa. Prospective climate-based models have recently been developed that flag areas at risk of RVFV transmission in endemic regions based on key environmental indicators that precede Rift Valley fever (RVF) epizootics and epidemics. Although the timing and locations of human case data from the 2006-2007 RVF outbreak in Kenya have been compared to risk zones flagged by the model, seroprevalence of RVF antibodies in wildlife has not yet been analyzed in light of temporal and spatial predictions of RVF activity. Primarily wild ungulate serum samples from periods before, during, and after the 2006-2007 RVF epizootic were analyzed for the presence of RVFV IgM and/or IgG antibody. Results show an increase in RVF seropositivity from samples collected in 2007 (31.8%), compared to antibody prevalence observed from 2000-2006 (3.3%). After the epizootic, average RVF seropositivity diminished to 5% in samples collected from 2008-2009. Overlaying maps of modeled RVF risk assessments with sampling locations indicated positive RVF serology in several species of wild ungulate in or near areas flagged as being at risk for RVF. Our results establish the need to continue and expand sero-surveillance of wildlife species Kenya and elsewhere in the Horn of Africa to further calibrate and improve the RVF risk model, and better understand the dynamics of RVFV transmission.
Reimann, Clemens; Bjorvatn, Kjell; Frengstad, Bjørn; Melaku, Zenebe; Tekle-Haimanot, Redda; Siewers, Ulrich
2003-07-20
Drinking water samples were collected throughout the Ethiopian part of the Rift Valley, separated into water drawn from deep wells (deeper than 60 m), shallow wells (<60 m deep), hot springs (T>36 degrees C), springs (T<32 degrees C) and rivers. A total of 138 samples were analysed for 70 parameters (Ag, Al, As, B, Ba, Be, Bi, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Er, Eu, F, Fe, Ga, Gd, Ge, Hf, Hg, Ho, I, In, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, NO(2), NO(3), Pb, Pr, Rb, Sb, Se, Si, Sm, Sn, SO(4), Sr, Ta, Tb, Te, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn, Zr, temperature, pH, conductivity and alkalinity) with ion chromatography (anions), spectrometry (ICP-OES and ICP-MS, cations) and parameter-specific (e.g. titration) techniques. In terms of European water directives and WHO guidelines, 86% of all wells yield water that fails to pass the quality standards set for drinking water. The most problematic element is fluoride (F), for which 33% of all samples returned values above 1.5 mg/l and up to 11.6 mg/l. The incidence of dental and skeletal fluorosis is well documented in the Rift Valley. Another problematic element may be uranium (U)-47% of all wells yield water with concentrations above the newly suggested WHO maximum acceptable concentration (MAC) of 2 microg/l. Fortunately, only 7% of the collected samples are above the 10 microg/l EU-MAC for As in drinking water.
NASA Astrophysics Data System (ADS)
Bentley, S.
2017-12-01
The European Union Water Framework Directive came into force in October 2000 committing European Union member states to achieve Good Ecological Status for all water bodies. By 2015 29% of rivers across England had achieved this level suggesting that these watercourse units are now functioning well. This study utilises recently published land cover data for England clipped to the floodplain boundary as defined by the 100 year return period discharge to examine the state of valley bottom vegetation and function for these Good Status rivers. Agricultural use of floodplain areas is high with cereal and horticulture covering an average of 24% and pasture accounting for some 37% of the area. Maximum values increase to 77% and 92% respectively. In all cases wetland accounts for less than 2% of the floodplain and rough grassland averages 7%. Such significant and widespread alteration to floodplain vegetation character suggests that the ecological functioning of this component of the fluvial system has been severely negatively impacted calling into question the Water Framework Directive status level. This is a fault of the Water Framework Directive process which only explicitly evaluates the hydromorphological component of the fluvial system for high status rivers preferring to infer functioning from biological indicators that are focused on in-channel assessments. The fundamental omission of floodplain condition in the Water Framework Directive process will result in only partial achievement of the original goals of the Directive with the majority of Europe's floodplains remaining in a highly degraded, non-functional state.
Ground-water quality in the southeastern Sacramento Valley aquifer, California, 1996
Milby Dawson, Barbara J.
2001-01-01
In 1996, the U.S. Geological Survey sampled 29 domestic wells and 2 monitoring wells in the southeastern Sacramento Valley as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. This area, designated as the NAWQA Sacramento subunit study area, was chosen because it had the largest amount of ground-water use in the Sacramento River Basin. The Sacramento subunit study area is about 4,400 square kilometers and includes intense agricultural and urban development. The wells sampled ranged from 14.9 to 79.2 meters deep. Ground-water samples from 31 wells were analyzed for 6 field measurements, 14 inorganic constituents, 6 nutrient constituents, organic carbon, 86 pesticides, 87 volatile organic compounds, tritium (hydrogen-3), radon-222, deuterium (hydrogen-2), and oxygen-18. Nitrate levels were lower than the 2000 drinking-water standards in all but one well, but many detections were in the range that indicated an effect by human activities on ground-water quality. Radon was detected in all wells, and was measured at levels above the proposed Federal 2000 maximum contaminant level in 90 percent of the wells. Five pesticides and one pesticide degradation product were detected in ground-water samples and concentrations were below 2000 drinking-water standards. All pesticides detected during this study have been used in the Sacramento Valley. Thirteen volatile organic compounds were detected in ground water. One detection of trichloroethene was above Federal 2000 drinking-water standards, and another, tetrachloromethane, was above California 1997 drinking-water standards; both occurred in a well that had eight volatile organic compound detections and is near a known source of ground-water contamination. Pesticides and volatile organic compounds were detected in agricultural and urban areas; both pesticides and volatile organic compounds were detected at a higher frequency in urban wells. Ground-water chemistry indicates that natural processes and human activities are affecting ground-water quality in the upper part of the southeastern Sacramento Valley aquifer. The factors identified as having an influence on ground-water quality were redox condition in the aquifer, depth within the aquifer, and land use overlying the aquifer. Nitrate concentra-tions showed a statistical correlation with each of these factors. Detections of pesticides and volatile organic compounds were too few to compare concentrations with the various factors, but the types of synthetic compounds detected were consistent with the sur-rounding land use. Sixty-one percent of the wells sampled in this study showed the effect of human activities on ground-water quality in the form of a nitrate concentration over 3 milligrams per liter or a detection of a pesticide or volatile organic compound. In general, the water quality in the southeastern Sacramento Valley aquifer was found suitable for most uses.
Rowe, Gary L.; Shapiro, Stephanie Dunkle; Schlosser, Peter
1999-01-01
Chlorofluorocarbons (CFC method) and tritium and helium isotopes (3H-3He method) were used as environmental tracers to estimate ground-water age in conjunction with efforts to develop a regional ground-water flow model of the buried-valley aquifer in the Dayton area, southwestern Ohio. This report describes results of CFC and water-quality sampling, summarizes relevant aspects of previously published work, and describes the use of 3H-3He ages to characterize temporal trends in ground-water quality of the buried-valley aquifer near Dayton, Ohio. Results of CFC sampling indicate that approximately 25 percent of the 137 sampled wells were contaminated with excess CFC's that rendered the ground water unsuitable for age dating. Evaluation of CFC ages obtained for the remaining samples indicated that the CFC compounds used for dating were being affected by microbial degradation. The degradation occurred under anoxic conditions that are found in most parts of the buried-valley aquifer. As a result, ground-water ages derived by the CFC method were too old and were inconsistent with measured tritium concentrations and independently derived 3H-3He ages. Limited data indicate that dissolved methane may play an important role in the degradation of the CFC's. In contrast, the 3H-3He technique was found to yield ground-water ages that were chemically and hydrologically reasonable. Ground-water ages derived by the 3H-3He technique were compared to values for selected water- quality characteristics to evaluate temporal trends in ground-water quality in the buried- valley aquifer. Distinct temporal trends were not identified for pH, alkalinity, or calcium and magnesium because of rapid equilibration of ground-water with calcite and dolomite in aquifer sediments. Temporal trends in which the amount of scatter and the number of outlier concentrations increased as ground-water age decreased were noted for sodium, potassium, boron, bromide, chloride, ammonia, nitrate, phosphate, sulfate, and organic carbon. Elevated concentrations of these constituents in shallow ground water are probably related to human activities. Temporal trends in which concentrations declined as ground-water age increased may reflect natural processes that reduce constituent concentrations to low levels. For example, the absence of nitrate detections in ground water recharged before 1980 may indicate natural removal of nitrate by bacterially mediated denitrification. Temporal trends observed for dissolved oxygen, iron, nitrate and silica indicate that these constituents may help identify recently (post-1990) recharged ground water.
Behavior of Aluminum in Solid Propellant Combustion
1982-06-01
dry pressing 30% Valley Met H- 30 aluminum, 7% carnauba wax , and 63% 100 P AP. One sample was prepared using as received H-30, a second sample used pre...34propellant" formulations. The formulations included dry pressed AP/AI, and AP/AI/ Wax samples. Sandwiches were also prepared consisting of an aluminum...Binder flame instead of by aluminum exposure during accumulate break-up. Combustion of AP/AI/ Wax Samples A set of propellant samples were prepared by
We reviewed compliance monitoring requirements in the European Union (EU), the United States(USA), and the Oslo-Paris Convention for the protection of the marine environment of the North-East Atlantic (OSPAR), and evaluated if these are met by passive sampling methods for nonpola...
Impact of land use change on soil organic matter dynamics in subalpine grassland
NASA Astrophysics Data System (ADS)
Meyer, Stefanie; Leifeld, Jens; Bahn, Michael; Fuhrer, Jürg
2010-05-01
Information regarding the response of soil organic matter (SOM) in soils to past and expected future land use changes in the European Alps is scarce. Understanding this response requires knowledge of size and residence times of SOM fractions with distinct stabilities. In order to quantify differences between types of land use in the amount, distribution and turnover rates of soil organic carbon (SOC) in subalpine grassland soils, we used soil aggregate and SOM density fractionation in combination with 14C dating. Samples were taken along gradients of different types of land use from meadow (M) to pasture (P) and to abandoned grassland (A) in the Stubai Valley and in the Matsch Valley. Sampling sites in both areas were located at equal altitude (1880 m and 1820 m, respectively) with the same parent material and soil type, but the Matsch Valley receives 400-500 mm less annual rainfall. SOC stocks in the top 10 cm were 2.47 ± 0.32 (M), 2.75 ± 0.32 (P), and 2.50 ± 0.31 kg C/m2 (A) in the Stubai Valley and 2.25 ± 0.14 (M), 3.45 ± 0.22 (P), 3.16 ± 0.27 kg C/m2(A) in the Matsch Valley. Three aggregate size classes were separated by wet sieving: 2 mm. The light floating fraction (wPOM, ρ >1 g/cm3) was included in the analysis. Free (f-) and occluded particulate organic matter (oPOM) were isolated from each aggregate size class (ρ >1.6 g/cm3). At both locations, more than 80% of SOC was stored in small (0.25-2 mm) and large (>2 mm) macroaggregates, but no trend in relation to the different types of land use could be detected. The fraction of C in fPOM and in oPOM in all aggregate size classes was highest for soil from abandoned grasslands. The bulk soil of the abandoned site in the Stubai Valley showed a significantly higher share of fPOM-C and oPOM-C and a higher amount of wPOM-C as compared to the soil from managed grassland, whereas in the Matsch Valley pasture soil had a significantly higher wPOM-C content. At both sites, 13C natural abundance analyses revealed a gradient in 13C between density fractions. wPOM was particularly useful to reveal differences between sampling sites. Radiocarbon values emphasized the importance of this fraction for the calculation of the turnover of bulk soil C. wPOM turned out to be the most active fraction turning over in 2-4 years. Bulk SOC turnover time was approximately 46 years for pasture soil and 78 years for meadow soil. In conclusion, density fractionation produced homogenous fractions allowing detection of differences between different land use types. However, C distribution among aggregates did not systematically differ.
Evaluation of Ground Water Near Sidney, Western Nebraska, 2004-05
Steele, G.V.; Sibray, S.S.; Quandt, K.A.
2007-01-01
During times of drought, ground water in the Lodgepole Creek area around Sidney, western Nebraska, may be insufficient to yield adequate supplies to private and municipal wells. Alternate sources of water exist in the Cheyenne Tablelands north of the city, but these sources are limited in extent. In 2003, the U.S. Geological Survey and the South Platte Natural Resources District began a cooperative study to evaluate the ground water near Sidney. The 122-square-mile study area lies in the south-central part of Cheyenne County, with Lodgepole Creek and Sidney Draw occupying the southern and western parts of the study area and the Cheyenne Tablelands occupying most of the northern part of the study area. Twenty-nine monitoring wells were installed and then sampled in 2004 and 2005 for physical characteristics, nutrients, major ions, and stable isotopes. Some of the 29 sites also were sampled for ground-water age dating. Ground water is limited in extent in the tableland areas. Spring 2005 depths to ground water in the tableland areas ranged from 95 to 188 feet. Ground-water flow in the tableland areas primarily is northeasterly. South of a ground-water divide, ground-water flows southeasterly toward Lodgepole Creek Valley. Water samples from monitoring wells in the Ogallala Group were predominantly a calcium bicarbonate type, and those from monitoring wells in the Brule Formation were a sodium bicarbonate type. Water samples from monitoring wells open to the Brule sand were primarily a calcium bicarbonate type at shallow depths and a sodium bicarbonate type at deeper depths. Ground water in Lodgepole Creek Valley had a strong sodium signature, which likely results from most of the wells being open to the Brule. Concentrations of sodium and nitrate in ground-water samples from the Ogallala were significantly different than in water samples from the Brule and Brule sand. In addition, significant differences were seen in concentrations of calcium between water samples from the Ogallala and the Brule sand. Median concentrations of nitrate varied by aquifer-2.6 milligrams per liter (Ogallala), 2.1 milligrams per liter (Brule), and 1.3 milligrams per liter (Brule sand). The chemistry of the ground water in the study area indicates that ground water flows from recharge areas in both the tableland areas and Lodgepole Creek Valley to discharge areas beyond the study area. Recharging water that percolates into the Ogallala in the tableland areas either enters the Ogallala aquifer, flows along the Ogallala-Brule contact, or enters Brule fractures or sand. Although limited in amount, ground water flowing along the Ogallala-Brule contact or in the Brule fractures or sand appears to be the predominant means by which water moves from the tableland areas to Lodgepole Creek Valley. Apparent ground-water ages from chlorofluorocarbon and sulfur hexafluoride data generally were similar. Age of ground water for most monitoring wells located in Lodgepole Creek Valley ranged from the mid- to late 1960s to the early 1990s. Ages of ground water in samples from monitoring wells located in tableland draw areas ranged from the mid-1980s to the early 1990s. Water in the Brule (areas without known secondary permeability structures) or deeper Brule sand aquifer was substantially older than water in the Ogallala aquifer and probably was recharged between 10,000 to 30,000 years before present. The stable isotopic data indicate that the ground water in the study area probably originated from precipitation. Ground water in Lodgepole Creek and the tableland areas are similar in chemistry. However, there appears to be limited interaction between ground water within the Ogallala to the north of Sidney and Lodgepole Creek Valley. Available data indicate that although some of the ground water in the Ogallala likely flows across the Ogallala-Brule contact, most of it does not move toward Lodgepole Creek.
Shallow ground-water quality beneath rice areas in the Sacramento Valley, California, 1997
Dawson, Barbara J.
2001-01-01
In 1997, the U.S. Geological Survey installed and sampled 28 wells in rice areas in the Sacramento Valley as part of the National Water-Quality Assessment Program. The purpose of the study was to assess the shallow ground-water quality and to determine whether any effects on water quality could be related to human activities and particularly rice agriculture. The wells installed and sampled were between 8.8 and 15.2 meters deep, and water levels were between 0.4 and 8.0 meters below land surface. Ground-water samples were analyzed for 6 field measurements, 29 inorganic constituents, 6 nutrient constituents, dissolved organic carbon, 86 pesticides, tritium (hydrogen- 3), deuterium (hydrogen-2), and oxygen-18. At least one health-related state or federal drinking-water standard (maximum contaminant or long-term health advisory level) was exceeded in 25 percent of the wells for barium, boron, cadmium, molybdenum, or sulfate. At least one state or federal secondary maximum contaminant level was exceeded in 79 percent of the wells for chloride, iron, manganese, specific conductance, or dissolved solids. Nitrate and nitrite were detected at concentrations below state and federal 2000 drinking-water standards; three wells had nitrate concentrations greater than 3 milligrams per liter, a level that may indicate impact from human activities. Ground-water redox conditions were anoxic in 26 out of 28 wells sampled (93 percent). Eleven pesticides and one pesticide degradation product were detected in ground-water samples. Four of the detected pesticides are or have been used on rice crops in the Sacramento Valley (bentazon, carbofuran, molinate, and thiobencarb). Pesticides were detected in 89 percent of the wells sampled, and rice pesticides were detected in 82 percent of the wells sampled. The most frequently detected pesticide was the rice herbicide bentazon, detected in 20 out of 28 wells (71 percent); the other pesticides detected have been used for rice, agricultural, and non-agricultural purposes. All pesticide concentrations were below state and federal 2000 drinking-water standards. The relation of the ground-water quality to natural processes and human activities was tested using statistical methods (Spearman rank correlation, Kruskal?Wallis, or rank-sum tests) to determine whether an influence from rice land-use or other human activities on ground-water chemistry could be identified. The detection of pesticides in 89 percent of the wells sampled indicates that human activities have affected shallow ground-water quality. Concentrations of dissolved solids and inorganic constituents that exceeded state or federal 2000 drinking-water standards showed a statistical relation to geomorphic unit. This is interpreted as a relation to natural processes and variations in geology in the Sacramento River Basin; the high concentrations of dissolved solids and most inorganic constituents did not appear to be related to rice land use. No correlation was found between nitrate concentration and pesticide occurrence, indicating that an absence of high nitrate concentrations is not a predictor of an absence of pesticide contamination in areas with reducing ground-water conditions in the Sacramento Valley. Tritium concentrations, pesticide detections, stable isotope data, and dissolved-solids concentrations suggest that shallow ground water in the ricegrowing areas of the Sacramento Valley is a mix of recently recharged ground water containing pesticides, nitrate, and tritium, and unknown sources of water that contains high concentrations of dissolved solids and some inorganic constituents and is enriched in oxygen-18. Evaporation of applied irrigation water, which leaves behind salt, accounts for some of the elevated concentrations of dissolved solids. More work needs to be done to understand the connections between the land surface, shallow ground water, deep ground water, and the drinking-water supplies in the Sacramento Valley.
Geology and MER target site characteristics along the southern rim of Isidis Planitia, Mars
Crumpler, L.S.; Tanaka, K.L.
2003-01-01
The southern rim of the Isidis basin contains one of the highest densities of valley networks, several restricted paleolake basins, and the stratigraphically lowest (oldest) terrain on Mars. Geologic mapping in Viking, MGS/MOC, and MOLA data, Odyssey/ THEMIS data, and other multispectral data products supports the presence of extensive fans of debris and sediments deposited along the inner rim of the Isidis basin where large valleys enter the lowlands. Additional processes subsequent to the period of intense fluvial activity, including mass flow analogous to some glacial processes, have contributed to the materials accumulated on the margins of the Isidis basin. These have occurred along preexisting channels and valleys at the termini of major channels where they enter the plains along the highland-lowland boundary. If the abundant valley networks in highland terrains are the result of runoff accompanied by saturated groundwater flow, as has been suggested in previous studies of ancient fluvial highland terrains, then the extreme age and abundance of early valley networks in the Libya Montes highland rocks should have resulted in deposition of materials that record evidence for the long-term presence of water in the form of aqueous alteration of polycrystalline constituents. The material deposited along the basin margin is likely to consist of ancient altered highland rocks in several physical states (weathered, rounded, and angular) exposing both weathered and altered surfaces, and exposures of alteration profiles in fractured faces and unweathered material from rock interiors. Debris fans shed off the southern rim of Isidis Planitia should contain materials that have experienced possible saturated groundwater flow, residence within paleolake basins, and derivative materials deposited during the most fluvially intensive part of Martian geologic history. Many of these materials have also been reworked by ice-related processes. In situ measurements of the ancient crustal materials, in the form of rocks within the debris fans, and the weathered condition of the rocky material are potential sources for mineralogical evidence of climatic conditions in earliest Martian geologic history. The absence of alteration within rocks would, on the other hand, support the hypothesis that fluvial runoff during the earliest history of Mars was geologically brief rather than long-term and that long-term saturated groundwater flow was not present. Determination of the presence or absence of alteration would have corresponding implications for hypotheses requiring the long-term presence of aqueous solutions (i.e., complex organic compounds and life). A proposed MER site along the margin addresses realistic field science objectives of the Mars Exploration Rover mission and the current goals of the Mars Exploration Program. In situ measurements may be important in deriving estimates of the longevity and intensity of past wetter climates. Copyright 2003 by the American Geophysical Union.
Adrian, B.M.; Frisken, J.G.; Bradley, L.A.; Taylor, Cliff D.; McHugh, J.B.
1987-01-01
In the summer of 1985, the U.S. Geological Survey conducted a reconnaissance geochemical survey of the Skedaddle (CA-020-612) and Dry Valley Rim (CA-020-615) Wilderness Study Areas in Lassen County, California, and Washoe County, Nevada.Skedaddle and Dry Valley Rim are contiguous wilderness study areas (WSA) located in the eastern part of the Modoc Plateau in Lassen County, northeastern California, and Washoe County, northwestern Nevada (fig. 1). The Skedaddle study area encompasses 39,420 acres and the Dry Valley Rim study area encompasses 54,480 acres of Bureau of Land Management administered public land about 25 mi east of Susanville, California. The Skedaddle study area is bounded on the east by the Skedaddle road, on the north by the Smoke Creek Road, on the south by the Wendel road, and on the west by the rim west of Wendel Canyon. The Dry Valley Rim study area is bounded on the east by the lower Smoke Creek road, the Dry Valley road, and the Pipe Springs Road. The northern boundary is the Smoke Creek Ranch road, the southern boundary the Wendel road, and the western boundary the east-side Skedaddle road. Access to the study areas is provided by several light-duty dirt roads and ways that join the boundary roads. Elevations range from 3,800 (1158 m) to 7,552 ft (2302 m). Steep rim rock walls and talus-covered canyons are common in the eastern third of the Dry Valley Rim study area, and the western third of the Skedaddle study area, while the majority of both study areas is gradually sloping, covered only by sparse sagebrush. Existing geologic maps that cover the two study areas consist of Lydon and others (I960), Bonham (1969), and Diggles and others (1986).The Skedaddle Wilderness Study Area consists of two parallel ridges, the Skedaddle Mountains and the Amedee Mountains. The ridges bound the Wendel and Spencer basins, an area of bleached and silicified rocks. Dry Valley Rim is a 17-mi (5.2 m)-long north-south-trending fault block that is situated 1,500 ft (457 m) above the Smoke Creek Desert to the east. The rim provides good exposure of the thick sequences of volcanic rocks that underlie the wilderness study area.The rocks of the study areas consist mostly of Tertiary basalt, andesite, and lahar with minor amounts of rhyolitic ash-flow tuff, rhyolite, and dacite. Surficial deposits consist of colluvium, alluvium, and talus, as well as aeolian, lacustrine, and fluvial deposits.
Reid, Kerry; Crochelet, Estelle; Bloomer, Paulette; Hoareau, Thierry B
2016-10-01
Due to their geographic isolation, biotas of oceanic islands are likely influenced by episodic long distance dispersal events, but such observations are scarce. In June 2012, fishermen from Réunion Island caught an unknown specimen of grouper, identified as dusky grouper Epinephelus marginatus (Lowe, 1834). This was highly unexpected considering the large distance of its closest verified occurrence (South Africa, ∼2500km). To identify the origin of this specimen and the mechanisms driving this potential long distance colonization, we combined genetic analyses and hydrodynamic connectivity modeling approaches. Molecular markers and samples from various locations across the distribution range resulted in the identification of three putative source populations. The Réunion specimen clustered genetically with South Africa. The estimated spawning period in relation to the connectivity modeling of larvae showed no possible direct connection between South Africa and Réunion. However, connectivity was predicted through intermediate stepping stone populations likely located around the southern tip of Madagascar, where the occurrence of the species has yet to be verified. The results further highlight the potential role of the cyclone Bingiza (February 2011) in the connection between Madagascar and Réunion. This shows that cyclones may be an important driver in long distance colonization of oceanic islands. Copyright © 2016 Elsevier Inc. All rights reserved.
Gonzales, J. L.; Elbers, A. R. W.; Bouma, A.; Koch, G.; De Wit, J. J.; Stegeman, J. A.
2010-01-01
Please cite this paper as: Gonzales et al. (2010) Low‐pathogenic notifiable avian influenza serosurveillance and the risk of infection in poultry – a critical review of the European Union active surveillance programme (2005–2007). Influenza and Other Respiratory Viruses 4(2), 91–99. Background Since 2003, Member States (MS) of the European Union (EU) have implemented serosurveillance programmes for low pathogenic notifiable avian influenza (LPNAI) in poultry. To date, there is the need to evaluate the surveillance activity in order to optimize the programme’s surveillance design. Objectives To evaluate MS sampling operations [sample size and targeted poultry types (PTs)] and its relation with the probability of detection and to estimate the PTs relative risk (RR) of being infected. Methods Reported data of the surveillance carried out from 2005 to 2007 were analyzed using: (i) descriptive indicators to characterize both MS sampling operations and its relation with the probability of detection and the LPNAI epidemiological situation, and (ii) multivariable methods to estimate each PTs RR of being infected. Results Member States sampling a higher sample size than that recommended by the EU had a significantly higher probability of detection. Poultry types with ducks & geese, game‐birds, ratites and “others” had a significant higher RR of being seropositive than chicken categories. The seroprevalence in duck & geese and game‐bird holdings appears to be higher than 5%, which is the EU‐recommended design prevalence (DP), while in chicken and turkey categories the seroprevalence was considerably lower than 5% and with that there is the risk of missing LPNAI seropositive holdings. Conclusion It is recommended that the European Commission discusses with its MS whether the results of our evaluation calls for refinement of the surveillance characteristics such as sampling frequency, the between‐holding DP and MS sampling operation strategies. PMID:20167049
NASA Astrophysics Data System (ADS)
Haramoto, E.
2018-03-01
In this study, the prevalence of various waterborne pathogens in water samples collected in the Kathmandu Valley, Nepal, and the applicability of Escherichia coli as an indicator of pathogen contamination in groundwater were assessed. Fifty-three water samples, including shallow groundwater and river water, were analyzed to examine the presence of protozoan (oo)cysts via fluorescence microscopy and that of viral and bacterial genomes via quantitative PCR. At least one of the seven types of pathogens tested (i.e., Cryptosporidium, Giardia, human adenoviruses, noroviruses of genogroups I and II, group A rotaviruses, and Vibrio cholerae) was detected in 68% (15/22) of the shallow dug well water samples; groundwater in the shallow dug wells was more contaminated compared with that in shallow tube wells (8/15, 53%). River water and sewage samples were contaminated with extremely high concentrations of multiple pathogens, whereas a tap water sample supplied by a water tanker tested positive for human adenoviruses and V. cholerae. The detection of host-specific Bacteroidales genetic markers revealed the effects of human and animal feces on groundwater contamination. The tested pathogens were sometimes detected even in E. coli-negative groundwater samples, indicative of the limitations of using E. coli as an indicator for waterborne pathogens in groundwater.
Lower tropospheric ozone and aerosol measurements at a coastal mountain site in Central California
NASA Astrophysics Data System (ADS)
Post, A.; Faloona, I. C.; Lighthall, D.; Wexler, A. S.; Cliff, S. S.; Conley, S. A.; Zhao, Y.
2013-12-01
Increasing concern over the impacts of exogenous air pollution in California's Central Valley has prompted the establishment of a coastal, high altitude monitoring site at the Chews Ridge Observatory (1550 m) approximately 30 km east of Point Sur in Monterey County, operated by the Monterey Institute for Research in Astronomy. Eighteen months of ozone and aerosol measurements are presented in the context of long-range transport and its potential impact on surface air quality in the southern San Joaquin Valley. Moreover, several ozone surveys have been conducted by aircraft upwind, over the Pacific Ocean, and downwind, over the Central Valley, to characterize horizontal and vertical transport across the coastal mountains. Diurnal variations present at Chews Ridge indicate the formation of a convective boundary layer on the ridge during the daytime leading to a 6-8 ppb decrease in ozone accompanied by a rise in specific humidity of 2-3 g/kg due to coupling with the forest. During the nighttime, the sampled air masses are representative of free tropospheric conditions which have not been significantly influenced by either local emissions nor convective coupling to the surface. The maximum daily 8-hour average ozone concentration at Chews Ridge is used in lagged correlation analysis with two sites in the San Joaquin Valley, Fresno and Arvin, to de-emphasize the influence of locally produced, diurnally cycled ozone. The correlation coefficients (~0.60) peak between 9-21 hour lag and tend to decorrelate completely within 4-5 days. These and other analyses along with data provided by the aircraft sampling are used to provide a deeper understanding of ozone transport into the San Joaquin Valley. Aerosol size is measured with a scanning mobility particle sizer and composition is analyzed with an 8-stage rotating drum impactor whose substrates are characterized by X-ray fluorescence. Various elemental ratios and back trajectory calculations are used to infer the temporal patterns of influence that long range transport has on California air quality.
Hydrogeology and water quality of the Shell Valley Aquifer, Rolette County, North Dakota
Strobel, M.L.
1997-01-01
The Shell Valley aquifer is the sole source of water for the city of Belcourt and the primary source of water for most of the Turtle Mountain Indian Reservation. The Turtle Mountain Band of Chippewa Indians is concerned about the quantity and quality of water in the Shell Valley aquifer, which underlies about 56 square miles in central Rolette County and has an average saturated thickness of about 35 feet. Water levels across most of the Shell Valley aquifer fluctuate with variations in precipitation but generally are stable. Withdrawals from the north well field decreased slightly during 1976-95, but withdrawals from the south well field increased during 1983-95. Water levels in the south well field declined as withdrawals increased. The average decline during the last 8 years was about 1.75 feet per year. The water level has reached the well screen in at least one of the production wells. Most of the water in the aquifer is a bicarbonate type and has dissolved-solids concentrations ranging from 479 to 1,510 milligrams per liter. None of the samples analyzed had detectable concentrations of pesticides, but hydrocarbons were detected in both ground- and surfacewater samples. Polycyclic aromatic hydrocarbons (PAH) were the most frequently detected hydrocarbons. Benzene, toluene, ethylbenzene, and xylene (BTEX), polychlorinated biphenyls (PCB), and pentachlorophenol (PCP) also were detected.Generally, the Shell Valley aquifer is an adequate source of water for current needs, but evaluation of withdrawals in relation to a knowledge of aquifer hydrology would be important in quantifying sustainable water supplies. Water quality in the aquifer generally is good; the Turtle Mountain Band of Chippewa Indians filters the water to reduce concentrations of dissolved constituents. Hydrocarbons, although present in the aquifer, have not been quantified and may not pose a general health risk. Further analysis of the quantity and distribution of the hydrocarbons would be useful to understand their sources and implications for water use.
Minor and Trace Element Chemistry of Urban NS-Soot from the Central Valley of CA, USA
NASA Astrophysics Data System (ADS)
Kleich, S. J.; Hooper, R.
2017-12-01
During a recent study of metal transport in the Central Valley of California, it was noted that ns-soot (soot) occurred as complex clusters of graphene-like spheres admixed with other aerosols and were usually the dominant component of PM2.5 air particulates. These soot clusters contained a wide variety of metals of environmental concern such as As,Pb,Cr, and Ni. This study reports semi-quantitative results for 20 minor and trace elements (calibrated with Smithsonian microbeam standards) using a 200kV Transmission Electron Microscope, EDS, and SAED. This study also examined the mineralogy and crystallinity of admixed aerosols within composite soot clusters. Samples selected represent three contrasting urban settings in the Central Valley: Woodland, on the western side of the valley (Interstate highway to the east); Stockton, an inland sea-port and land transportation corridor in the center of the valley; and Roseville, a major rail-transport hub to the east. The wet/dry Mediterranean climate of California resulted in pronounced seasonal variations in total metal content. Soot cluster chemistry is highly variable however certain patterns emerged. Soot collected during the wet season is generally more aciniform, less structurally complex, and had lower sulfur (sulfate) concentrations but still had significant levels of transition metals (V,Cr,Mn,Fe,Ni,Zn and Pb) . Dry season soot was predominantly admixed with sulfate aerosols, and enriched in alkalis and alkaline earth metals. Stockton (wet-season) soot had up to 6000ppm of Pb. There is appreciable Pb (210ppm-2600ppm) in 38% of samples from Roseville but no Pb greater than 200ppm in Woodland. The highest overall total metals were found in Roseville soot with appreciable As(670ppm), V(100ppm), Pb(2600ppm), Zn(4000 ppm), Cr(90ppm), and Ni(300ppm). Heavy transport (road/rail/port) correlates with higher metal contents regardless of climate.
Voytek, M.A.; Priscu, J.C.; Ward, B.B.
1999-01-01
Marked differences in the concentrations of major ions and cations, macronutrient chemistry and general trophic status exist among the lakes of the McMurdo dry valleys in Antarctica. These differences have been attributed to both variations in stream inputs and in situ lake processes (Priscu, 1995; Lizotte et al., 1996, Spigel and Priscu, 1996). This study examines the role of nitrifying bacteria in nitrogen transformations in these lakes. Applying two polymerase chain reaction (PCR) assays targeting the 16S rRNA genes of ammonia-oxidizing bacteria and the active site of the ammonia monooxygenase gene (amoA), the distribution of ammonia-oxidizers was examined in six Antarctic lakes: Lake Bonney, Lake Hoare, Lake Fryxell and Lake Joyce in the Taylor Valley, Lake Miers in the the Miers Valley and Lake Vanda in the Wright Valley. Using a two stage amplification procedure, ammonia-oxidizers from both the beta and gamma- subclasses of the Proteobacteria were detected and their relative abundances were determined in samples collected from all sites. Ammonia-oxidizers were detected in all lakes sampled. Members of the gamma subclass were only present in the saline lakes. In general, nitrifiers were most abundant at depths above the pycnocline and were usually associated with lower concentrations of NH4 and elevated concentrations of NO3 or NO2. The distribution of nitrifiers suggests that the primary N2O peak observed in most of the lakes was produced via nitrification. Preliminary data on the rate of nitrification (Priscu et al., 1996) support the occurrence of nitrification and the presence of nitrifiers at the depth intervals where nitrifiers were detected. In all lakes, except Lake Miers, the data indicate that nitrifying bacteria have an important role in the vertical distribution of nitrogen compounds in these systems.
Effects of sampling design on age ratios of migrants captured at stopover sites
Jeffrey F. Kelly; Deborah M. Finch
2000-01-01
Age classes of migrant songbirds often differ in migration timing. This difference creates the potential for age-ratios recorded at stopover sites to vary with the amount and distribution of sampling effort used. To test for these biases, we sub-sampled migrant capture data from the Middle Rio Grande Valley of New Mexico. We created data sets that reflected the age...
Amoebae from antarctic soil and water.
Brown, T J; Cursons, R T; Keys, E A
1982-01-01
Samples of soil and water were taken from the McMurdo Sound-Dry Valley region of Antarctica. Of the 70 samples cultured, 22 yielded amoebae capable of clonal growth at 30 degrees C. None of the isolates was pathogenic for mice. Acanthamoeba isolates appeared to show better survival potential than Naegleria isolates. PMID:7125658
Kinsey, Willie B.; Johnson, Mark V.; Gronberg, JoAnn M.
2005-01-01
This report contains pesticide, volatile organic compound, major ion, nutrient, tritium, stable isotope, organic carbon, and trace-metal data collected from 149 ground-water wells, and pesticide data collected from 39 surface-water stream sites in the San Joaquin Valley of California. Included with the ground-water data are field measurements of pH, specific conductance, alkalinity, temperature, and dissolved oxygen. This report describes data collection procedures, analytical methods, quality assurance, and quality controls used by the National Water-Quality Assessment Program to ensure data reliability. Data contained in this report were collected during a four year period by the San Joaquin?Tulare Basins Study Unit of the United States Geological Survey's National Water-Quality Assessment Program. Surface-water-quality data collection began in April 1992, with sampling done three times a week at three sites as part of a pilot study conducted to provide background information for the surface-water-study design. Monthly samples were collected at 10 sites for major ions and nutrients from January 1993 to March 1995. Additional samples were collected at four of these sites, from January to December 1993, to study spatial and temporal variability in dissolved pesticide concentrations. Samples for several synoptic studies were collected from 1993 to 1995. Ground-water-quality data collection was restricted to the eastern alluvial fans subarea of the San Joaquin Valley. Data collection began in 1993 with the sampling of 21 wells in vineyard land-use settings. In 1994, 29 wells were sampled in almond land-use settings and 9 in vineyard land-use settings; an additional 11 wells were sampled along a flow path in the eastern Fresno County vineyard land-use area. Among the 79 wells sampled in 1995, 30 wells were in the corn, alfalfa, and vegetable land-use setting, and 1 well was in the vineyard land-use setting; an additional 20 were flow-path wells. Also sampled in 1995 were 28 wells used for a regional assessment of ground-water quality in the eastern San Joaquin Valley.
Groundwater flow processes and mixing in active volcanic systems: the case of Guadalajara (Mexico)
NASA Astrophysics Data System (ADS)
Hernández-Antonio, A.; Mahlknecht, J.; Tamez-Meléndez, C.; Ramos-Leal, J.; Ramírez-Orozco, A.; Parra, R.; Ornelas-Soto, N.; Eastoe, C. J.
2015-09-01
Groundwater chemistry and isotopic data from 40 production wells in the Atemajac and Toluquilla valleys, located in and around the Guadalajara metropolitan area, were determined to develop a conceptual model of groundwater flow processes and mixing. Stable water isotopes (δ2H, δ18O) were used to trace hydrological processes and tritium (3H) to evaluate the relative contribution of modern water in samples. Multivariate analysis including cluster analysis and principal component analysis were used to elucidate distribution patterns of constituents and factors controlling groundwater chemistry. Based on this analysis, groundwater was classified into four groups: cold groundwater, hydrothermal groundwater, polluted groundwater and mixed groundwater. Cold groundwater is characterized by low temperature, salinity, and Cl and Na concentrations and is predominantly of Na-HCO3-type. It originates as recharge at "La Primavera" caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal groundwater is characterized by high salinity, temperature, Cl, Na and HCO3, and the presence of minor elements such as Li, Mn and F. It is a mixed-HCO3 type found in wells from Toluquilla Valley and represents regional flow circulation through basaltic and andesitic rocks. Polluted groundwater is characterized by elevated nitrate and sulfate concentrations and is usually derived from urban water cycling and subordinately from agricultural return flow. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Twenty-seven groundwater samples contain at least a small fraction of modern water. The application of a multivariate mixing model allowed the mixing proportions of hydrothermal fluids, polluted waters and cold groundwater in sampled water to be evaluated. This study will help local water authorities to identify and dimension groundwater contamination, and act accordingly. It may be broadly applicable to other active volcanic systems on Earth.
Paleoglaciology of the Ala-Archa and Ak-Shyrak areas, Kyrgyz Tian Shan
NASA Astrophysics Data System (ADS)
Blomdin, R.; Beel, C.; Caffee, M. W.; Codilean, A.; Gribenski, N.; Harbor, J.; Heyman, J.; Hattestrand, C.; Ivanov, M.; Kassab, C.; Lifton, N. A.; Petrakov, D.; Rogozhina, I.; Stroeven, A. P.; Usubaliev, R.
2012-12-01
We employed detailed glacial geomorphological mapping of the Ala-Archa and Ak-Shyrak areas, Kyrgyz Tian Shan (Shan = Mountains) to build a paleoglaciological reconstruction. These two areas were selected because their glaciers constitute important freshwater reservoirs for downstream communities (the Kyrgyz capital Bishkek, and cities along the Syr Darja which drains towards the Aral Sea, respectively), and because fluctuations in their extent cause both variations in water supply and risks for glacial hazards. Five landform categories were mapped; glacial valleys, marginal moraines, glacial lineations, hummocky terrain, and melt-water channels. These landforms were mapped using a SRTM digital elevation model (DEM) with a 90 m resolution, Landsat 7 ETM+ satellite imagery with a 30 m resolution, Aster GDEM with a 30 m resolution, and Google Earth. This remotely sensed mapping was also checked and complemented by field mapping. The distribution of mapped landforms indicates restricted glaciations, mainly concentrated to the mountain areas. In both ranges marginal moraines extend beyond the furthest extent of glacial valleys. Furthermore, extensive areas of hummocky moraine in Ak-Shyrak extending beyond montane glacial valleys indicate glacial extents into the intermontane basins. Several series of lateral and terminal moraines in the Ala-Archa and Ak-Shyrak ranges have been identified and sampled for cosmogenic nuclide 10Be dating, while associated glaciofluvial sediment was sampled for optically-stimulated luminescence (OSL) and electron spin resonance (ESR) dating. Future work will involve using these samples to build a consistent chronology for glaciation and investigation of contrasts between paleoglaciological reconstructions of valleys within a single range but with different aspects, as well as between ranges. In the final stages of the project we will use intermediate complexity glacier flow models to examine paleoclimatic implications of the observed spatial and temporal patterns of glacier changes, focused in particular on the last glacial cycle.
Presence of faecal indicator bacteria in groundwaters in Kathmandu Valley, Nepal
NASA Astrophysics Data System (ADS)
Nishida, K.; Shrestha, S.; Tanaka, Y.; Haramoto, E.; Nakamura, T.; Osaka, K.; Chapagain, S.
2010-12-01
Groundwater quality is a critical problem in Kathmandu Valley, Nepal. The population of the city increased 6 times in the last six decades and more than half of water demand depends on groundwater resource. Nevertheless, few data of microorganism presence have been reported qualitatively in the central area of the valley. We investigated distribution of faecal indicator bacteria (Total coliforms and Escherichia coli) detected in wells and analyzed the variations of the concentrations. Groundwater samples were collected from 12 deep tube wells (170-300m depths) and 36 shallow tube wells and dug wells (3-20m depths) in Aug 2008, Jan 2009, Aug 2009 and Aug 2010. River waters were also collected for analyzing effect on groundwater quality. E. coli was detected from most of all wells; the concentrations were within 1 log cfu/100mL in deep tube wells and shallow tube wells while those in dug wells ranged from 1 to 3 log cfu/100mL. E. coli was detected at extremely high level in river water, from 5 to 7 log cfu/100mL, however, no clear relation was observed between E. coli concentrations in any types of groundwaters and distance of wells from adjacent rivers. These results indicate that both types of tube wells were rather protected and dug wells were most vulnerable for faecal contamination at very local scale. Genetic analysis of bacterial communities for deep well samples showed the existence of Enterobacter, Acinetobacter as well as Methane-metabolizing groups which provide information of possible indicators other than total coliforms or E. coli for groundwater management in the valley.
Dioxin reservoirs in southern Viet Nam--a legacy of Agent Orange.
Dwernychuk, L Wayne; Cau, Hoang Dinh; Hatfield, Christopher T; Boivin, Thomas G; Hung, Tran Manh; Dung, Phung Tri; Thai, Nguyen Dinh
2002-04-01
In the isolated Aluoi Valley of central Viet Nam, very high levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were measured in soil, fish fat, duck fat, pooled human blood and breast milk samples collected from A So village between 1996 and 1999. The village was situated on a former military base occupied by US Special Forces between 1963 and 1966. TCDD was a contaminant of the herbicide "Agent Orange", aerially sprayed in the valley between 1965 and 1970, and stored at the A So base. Measured levels were lower near the sites of two other former US bases in the valley which had been occupied for shorter periods of time. In areas where Agent Orange had been applied by low-flying aircraft, levels of TCDD in soil, food and human samples were elevated, but lower than those near the three former US bases. We confirm the apparent food chain transfer of TCDD from contaminated soil to cultured fish pond sediments to fish and duck tissues, then to humans as measured in whole blood and breast milk. We theorize that the Aluoi Valley is a microcosm of southern Viet Nam, where numerous reservoirs of TCDD exist in the soil of former military installations south of the former demilitarized zone. Large quantities of Agent Orange were stored at many sites, used in ground and aerial applications, and spilled. TCDD, through various forms of soil disturbance, can be mobilized from these reservoirs after decades below the surface, and subsequently, introduced into the human food chain.
McGuire, Virginia L.; Ryter, Derek W.; Flynn, Amanda S.
2012-01-01
The U.S. Geological Survey, in cooperation with the Papio-Missouri River Natural Resources District (PMRNRD), conducted this study to map the water-level altitude of 2009 within the Elkhorn River Valley, Missouri River Valley, and Platte River Valley alluvial aquifers; to present the predevelopment potentiometric-surface altitude within the Dakota aquifer; and to describe the age and quality of groundwater in the five principal aquifers of the PMRNRD in eastern Nebraska using data collected from 1992 to 2009. In addition, implications of alternatives to the current PMRNRD groundwater-quality monitoring approach are discussed. In the PMRNRD, groundwater altitude, relative to National Geodetic Vertical Datum of 1929, ranged from about 1,080 feet (ft) to 1,180 ft in the Elkhorn River Valley alluvial aquifer and from about 960 ft to 1,080 ft in the Missouri River Valley and Platte River Valley alluvial aquifers. In the PMRNRD, the estimated altitude of the potentiometric surface of the Dakota aquifer, predevelopment, ranged from about 1,100 ft to 1,200 ft. To assess groundwater age and quality, groundwater samples were collected from a total of 217 wells from 1992 to 2009 for analysis of various analytes. Groundwater samples collected in the PMRNRD from 1992 to 2009 and interpreted in this report were analyzed for age-dating analytes (chlorofluorocarbons), dissolved gases, major ions, trace elements, nutrients, stable isotope ratios, pesticides and pesticide degradates, volatile organic compounds, explosives, and 222radon. Apparent groundwater age was estimated from concentrations of chlorofluorocarbons measured in samples collected in 2000. Apparent groundwater-recharge dates ranged from older than 1940 in samples from wells screened in the Missouri River Valley alluvial aquifer to the early 1980s in samples from wells screened in the Dakota aquifer. Concentrations of major ions in the most recent sample per well collected from 1992 to 2009 indicate that the predominant water type was calcium bicarbonate. Samples from 4 wells exceeded the U.S. Environmental Protection Agency (USEPA) Secondary Drinking Water Regulation (SDWR) for sulfate [250 milligrams per liter (mg/L)], and samples from 4 wells exceeded the USEPA Drinking Water Advisory Table for sodium (30-60 mg/L). Eighteen of the 21 trace elements analyzed in samples from PMRNRD wells have USEPA drinking-water standards. Sixteen of the trace elements with USEPA standards were detected in the selected samples. In the samples selected for trace-element analysis, the only trace-element concentration that exceeded an enforceable USEPA drinking-water standard, the Maximum Contaminant Level (MCL), was for arsenic; arsenic concentration exceeded the USEPA MCL of 10 micrograms per liter (μg/L) in 4 percent of the samples. Trace-element concentrations that exceeded the USEPA SDWR or Lifetime Health Advisory level were iron (46 percent of the samples were greater than USEPA SDWR of 300 μg/L), manganese (70 percent of the samples were greater than USEPA SDWR of 50 μg/L), and strontium (4 percent of the samples were greater than USEPA Lifetime Health Advisory level of 4,000 μ/L). The concentration of nitrate plus nitrite as nitrogen (nitrate-N) in the most recent nutrient samples collected from the network wells and from one randomly selected well in the well nests from 1992 to 2009 for most wells (80 percent) ranged from less than 0.06 to 8.55 mg/L, with a median value of 0.12 mg/L. Concentrations of nitrate-N in 13 (7 percent) nutrient samples, 1992 to 2009, were greater than or equal to the USEPA MCL and Nebraska Title-118 standard of 10 mg/L, and concentrations of nitrate-N in 35 (18 percent) nutrient samples, 1992 to 2009, were greater than or equal to 5 mg/L, which is the PMRNRD action level for possible management implementation to reduce nitrate concentrations in groundwater. Of the 61 pesticides or pesticide degradates analyzed from 2007 to 2009, 21 were detected. Three of the 21 pesticides detected (alachlor, atrazine, and metolachlor) have established health-based criteria; all detections of these compounds were at concentrations less than their USEPA standards. From 2007 to 2009, 1 or more pesticide compounds were detected in 16 of the 82 network wells and in 18 of the 26 wells in well nests. From 2007 to 2009, the individual pesticide compounds that were detected most frequently were alachlor ethane sulfonic acid, a degradate of alachlor; deethylcyanazine acid, a degradate of cyanazine; and atrazine. Analytes with concentrations that exceeded 30 percent of the applicable Nebraska Title-118 standard were identified so that the PMRNRD can plan to monitor groundwater in the area and consider possible actions should the analyte concentrations continue to rise. The analytical results from the most recent samples collected in the network wells and all the wells in well nests from 1992 to 2009 indicate that, in at least 1 sample, there was a concentration that exceeded 30 percent of the Nebraska Title-118 standard for at least 1 of 3 major ions (chloride, fluoride, and sulfate), 1 nutrient (nitrate-N), 1 pesticide (atrazine), or 3 trace elements (arsenic, iron, and manganese). In addition, 30 percent of the USEPA MCL or Nebraska Title-118 standard for gross alpha activity likely was exceeded in samples from three wells screened in the Dakota aquifer. Study findings indicate that some alternatives to the current PMRNRD groundwater-sampling approach that could be considered are to collect fewer samples for nutrient analysis and to collect samples periodically for determining concentrations of additional analytes, particularly the analytes with concentrations that were at least 30 percent or more than the Nebraska Title-118 standard.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Jinyuan
A digitization scheme of sub-microampere current using a commercial comparator with adjustable hysteresis and FPGA-based Wave Union TDC has been tested. The comparator plus a few passive components forms a current controlled oscillator and the input current is sent into the hysteresis control pin. The input current is converted into the transition times of the oscillations, which are digitized with a Wave Union TDC in FPGA and the variation of the transition times reflects the variation of the input current. Preliminary tests show that input charges < 25 fC can be measured at > 50 M samples/s without a preamplifier.
Serologic evidence of exposure to Rift Valley fever virus detected in Tunisia
Bosworth, A.; Ghabbari, T.; Dowall, S.; Varghese, A.; Fares, W.; Hewson, R.; Zhioua, E.; Chakroun, M.; Tiouiri, H.; Ben Jemaa, M.; Znazen, A.; Letaief, A.
2015-01-01
Rift Valley fever virus (RVFv) is capable of causing dramatic outbreaks amongst economically important animal species and is capable of causing severe symptoms and mortality in humans. RVFv is known to circulate widely throughout East Africa; serologic evidence of exposure has also been found in some northern African countries, including Mauritania. This study aimed to ascertain whether RVFv is circulating in regions beyond its known geographic range. Samples from febrile patients (n = 181) and nonfebrile healthy agricultural and slaughterhouse workers (n = 38) were collected during the summer of 2014 and surveyed for exposure to RVFv by both serologic tests and PCR. Of the 219 samples tested, 7.8% of nonfebrile participants showed immunoglobulin G reactivity to RVFv nucleoprotein and 8.3% of febrile patients showed immunoglobulin M reactivity, with the latter samples indicating recent exposure to the virus. Our results suggest an active circulation of RVFv and evidence of human exposure in the population of Tunisia. PMID:26740887
Prudic, David E.
1978-01-01
A low-level radioactive-waste burial site, West Valley, N.Y., operated from 1963 to 1975, contains 12 refuse-filled trenches about 20 feet deep in till. Twenty-eight wells, 1.25 inch in diameter, were driven to selected depths in 11 of the 12 trenches to obtain gas and water samples for chemical and radiochemical analysis, water-level measurements for evaluation of trench-cover permeability. Gas from unsaturated refuse above the trench water level was detected in nearly all wells. Rapid water-level response in most wells to pumping of water from trench sumps 20 to 275 feet distant showed the refuse to be highly permeable. Described in detail are the methods and equipment used to (1) install the wells, (2) collect gas and water samples, and (3) monitor radiation and methane concentrations while driving wells into trenches. A record of each well driven into the burial trenches is included. (Woodard-USGS)
Genetics of Central Valley O. mykiss populations: drainage and watershed scale analyses
Nielsen, Jennifer L.; Pavey, Scott A.; Wiacek, Talia; Williams, Ian S.
2005-01-01
Genetic variation at 11 microsatellite loci described population genetic structure for Oncorhynchus mykiss in the Central Valley, California. Spatial and temporal variation was examined as well as relationships between hatchery and putative natural spawning anadromous stocks. Genetic diversity was analyzed at two distinct spatial scales: fine-scale within drainage for five populations on Clear Creek; between and among drainage diversity for 23 populations. Significant regional spatial structure was apparent, both within Clear Creek and among rainbow trout populations throughout the Central Valley. Significant differences in allelic frequencies were found among most river or drainage systems. Less than 1% of the molecular variance could be attributed to differences found between drainages. Hatchery populations were shown to carry similar genetic diversity to geographically proximate wild populations. Central Valley M = 0.626 (below the M < 0.68 threshold) supported recent population reductions within the Central Valley. However, average estimated effective population size was relatively high (Ne = 5066). Significant allelic differences were found in rainbow trout collected above and below impassable dams on the American, Yuba, Stanislaus and Tuolumne rivers. Rainbow trout sampled in Spring Creek were extremely bottlenecked with allelic variation at only two loci and an estimated effective population size of 62, suggesting some local freshwater O. mykiss stocks may be declining rapidly. These data support significant genetic population structure for steelhead and rainbow trout populations within the Central Valley across multiple scales. Careful consideration of this genetic diversity and its distribution across the landscape should be part of future conservation and restoration efforts.
Multi-scale curvature for automated identification of glaciated mountain landscapes
NASA Astrophysics Data System (ADS)
Prasicek, Günther; Otto, Jan-Christoph; Montgomery, David; Schrott, Lothar
2014-05-01
Automated morphometric interpretation of digital terrain data based on impartial rule sets holds substantial promise for large dataset processing and objective landscape classification. However, the geomorphological realm presents tremendous complexity in the translation of qualitative descriptions into geomorphometric semantics. Here, the simple, conventional distinction of V-shaped fluvial and U-shaped glacial valleys is analyzed quantitatively using the relation of multi-scale curvature and drainage area. Glacial and fluvial erosion shapes mountain landscapes in a long-recognized and characteristic way. Valleys incised by fluvial processes typically have V-shaped cross-sections with uniform and moderately steep slopes, whereas glacial valleys tend to have U-shaped profiles and topographic gradients steepening with distance from valley floor. On a DEM, thalweg cells are determined by a drainage area cutoff and multiple moving window sizes are used to derive per-cell curvature over a variety of scales ranging from the vicinity of the flow path at the valley bottom to catchment sections fully including valley sides. The relation of the curvatures calculated for the user-defined minimum scale and the automatically detected maximum scale is presented as a novel morphometric variable termed Difference of Minimum Curvature (DMC). DMC thresholds determined from typical glacial and fluvial sample catchments are employed to identify quadrats of glaciated and non-glaciated mountain landscapes and the distinctions are validated by field-based geological and geomorphological maps. A first test of the novel algorithm at three study sites in the western United States and a subsequent application to Europe and western Asia demonstrate the transferability of the approach.
Beever, Erik A.; Pyke, D.A.
2004-01-01
In contrast to the more incised riparian channels of central Nevada, we observed knickzones, downcutting, and incision only rarely and usually with limited extent in the walking surveys. Downcutting occurred most frequently and extensively in Strawberry and Snake creeks, due in part to their more erodible soils. According to a hydrogeomorphologist with extensive experience in Great Basin riparian systems, the sediment-delivery and hydrologic systems appeared relatively undisturbed in most reaches, with respect to grazing animals and other types of anthropogenic alteration. Site elevation of the 31 transects ranged from 1,950-2,987 m, and stream slope (i.e., gradient) was relatively steep (mean = 9.3%, range 3-16%). Strawberry Creek averaged the lowest maximum water depth, and correspondingly had greatest width/depth ratios. Baker Creek sites averaged the smallest amount of tree-canopy gaps, whereas Snake Creek sites on average had the largest proportion of gaps in understory vegetation. Sites in terrace-bound valley types averaged the lowest slope in the channel as well as the least cover of trees, litter, and vegetation overall, whereas alluviated, boulder-bed canyon sites averaged the greatest widths of the active channel. Sites in Lehman Creek averaged nearly twice as much coarse woody debris as sites from any other creek, whereas Baker Creek sites averaged greatest tree cover (mean = 67%, range 40 – 96%) and species richness (mean = 17.3 species). Multivariate ordinations suggested that sites in leveed outwash valleys and alluvial-fan-influenced valleys had the greatest inter-site heterogeneity in plant composition, whereas sites in incised moraine-filled valleys appeared most homogeneous. Differences among homogeneity of sites within vegetation types were less pronounced, but sites dominated by either aspen and Woodsʼ rose or narrow-leaved cottonwood had the most similar plant communities among sites of the same vegetation type. A number of species were faithful indicators of various valley and vegetation types, using either set of plant-frequency data. We estimate that all 31 sites could be subsequently re-sampled in 14-18 field days by individuals possessing familiarity of the riparian flora of the southern Snake Range. As with any research, monitoring-focused investigations must balance the concerns for number of ecosystem attributes measured, extensiveness in time and space of sampling periods and locations, and the time and cost of sampling.
76 FR 2663 - Endangered and Threatened Species; Take of Anadromous Fish
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-14
... Conservation Bank on the Sacramento River in the Central Valley, California. Permit 13675 authorizes indirect... species, taking of length measurements), tissue sampling, release of moribund fish or fish carcasses back...
Application of Droplet Digital PCR to Validate Rift Valley Fever Vaccines.
Ly, Hoai J; Lokugamage, Nandadeva; Ikegami, Tetsuro
2016-01-01
Droplet Digital™ polymerase chain reaction (ddPCR™) is a promising technique that quantitates the absolute concentration of nucleic acids in a given sample. This technique utilizes water-in-oil emulsion technology, a system developed by Bio-Rad Laboratories that partitions a single sample into thousands of nanoliter-sized droplets and counts nucleic acid molecules encapsulated in each individual particle as one PCR reaction. This chapter discusses the applications and methodologies of ddPCR for development of Rift Valley fever (RVF) vaccine, using an example that measures RNA copy numbers of a live-attenuated MP-12 vaccine from virus stocks, infected cells, or animal blood. We also discuss how ddPCR detects a reversion mutant of MP-12 from virus stocks accurately. The use of ddPCR improves the quality control of live-attenuated vaccines in the seed lot systems.
Root, J Jeffrey; Puskas, Robert B; Fischer, Justin W; Swope, Craig B; Neubaum, Melissa A; Reeder, Serena A; Piaggio, Antoinette J
2009-12-01
Raccoons are the reservoir for the raccoon rabies virus variant in the United States. To combat this threat, oral rabies vaccination (ORV) programs are conducted in many eastern states. To aid in these efforts, the genetic structure of raccoons (Procyon lotor) was assessed in southwestern Pennsylvania to determine if select geographic features (i.e., ridges and valleys) serve as corridors or hindrances to raccoon gene flow (e.g., movement) and, therefore, rabies virus trafficking in this physiographic region. Raccoon DNA samples (n = 185) were collected from one ridge site and two adjacent valleys in southwestern Pennsylvania (Westmoreland, Cambria, Fayette, and Somerset counties). Raccoon genetic structure within and among these study sites was characterized at nine microsatellite loci. Results indicated that there was little population subdivision among any sites sampled. Furthermore, analyses using a model-based clustering approach indicated one essentially panmictic population was present among all the raccoons sampled over a reasonably broad geographic area (e.g., sites up to 36 km apart). However, a signature of isolation by distance was detected, suggesting that widths of ORV zones are critical for success. Combined, these data indicate that geographic features within this landscape influence raccoon gene flow only to a limited extent, suggesting that ridges of this physiographic system will not provide substantial long-term natural barriers to rabies virus trafficking. These results may be of value for future ORV efforts in Pennsylvania and other eastern states with similar landscapes.
Iron Redox Transformations And Phosphorous Cycling In Tropical Soils
NASA Astrophysics Data System (ADS)
Peretyazhko, T.; Sposito, G.
2003-12-01
We are investigating the hypothesis that in highly weathered tropical soils iron oxidation-reduction reactions may mediate phosphorous solubility. In these soils phosphorous may be removed from the plant-available soil pool by sorption to Fe(III) oxides and by precipitation with Fe(III) to form insoluble minerals. The reduction of iron during episodic anoxic conditions has the potential to release phosphorous in a plant available form. We aim to explore the factors controlling Fe reduction and to evaluate the role of Fe reduction in P solubilization. Soil samples were collected along a toposequence (ridge-slope-valley) in the Luquillo Experimental Forest, Puerto Rico. Besides precipitation, the valley soils receive additional water through subsurface and upland runoff. These soils are poorly-drained and, therefore, periodically saturated with water, which creates anoxic conditions. Two series of incubation experiments were carried out on air-dried and freshly-sampled valley soils. During a 14-day incubation period, increasing production of Fe(II) was detected in both types of soil sample. We also found positive correlations between the concentrations of soluble Fe(II), pH, and soluble P. In general, the total amounts of Fe(II) and P produced were higher in the air-dried soil, mainly due to differences in microbial activity. To examine further the factors controlling Fe reduction and P solubilization, we are performing soil incubation experiments in the presence of "electron shuttle" compound (AQDS). SEM and STXM techniques will be applied to detect the formation of Fe(II) secondary minerals.
Wylie, G.D.; Casazza, Michael L.; Gregory, C.J.; Halstead, B.J.
2010-01-01
The Giant Gartersnake (Thamnophis gigas) is restricted to wetlands of the Central Valley of California. Because of wetland loss in this region, the Giant Gartersnake is both federally and state listed as threatened. We conducted markrecapture studies of four populations of the Giant Gartersnake in the Sacramento Valley (northern Central Valley), California, to obtain baseline data on abundance and density to assist in recovery planning for this species. We sampled habitats that ranged from natural, unmanaged marsh to constructed managed marshes and habitats associated with rice agriculture. Giant Gartersnake density in a natural wetland (1.90 individuals/ha) was an order of magnitude greater than in a managed wetland subject to active season drying (0.17 individuals/ha). Sex ratios at all sites were not different from 1 1, and females were longer and heavier than males. Females had greater body condition than males, and individuals at the least disturbed sites had significantly greater body condition than individuals at the managed wetland. The few remaining natural wetlands in the Central Valley are important, productive habitat for the Giant Gartersnake, and should be conserved and protected. Wetlands constructed and restored for the Giant Gartersnake should be modeled after the permanent, shallow wetlands representative of historic Giant Gartersnake habitat. ?? 2010 Society for the Study of Amphibians and Reptiles.
Newhouse, M.W.; Hanson, R.T.; Wentworth, C.M.; Everett, Rhett; Williams, C.F.; Tinsley, J.C.; Noce, T.E.; Carkin, B.A.
2004-01-01
To better identify the three-dimensional geohydrologic framework of the Santa Clara Valley, lithologic, geologic, geophysical, geomechanical, hydraulic, and water-chemistry data were collected from eight ground-water multiple-well monitoring sites constructed in Santa Clara County, California, as part of a series of cooperative studies between the U.S. Geological Survey and the Santa Clara Valley Water District. The data are being used to update and improve the three-dimensional geohydrologic framework of the basin and to address issues related to water supply, water chemistry, sequence stratigraphy, geology, and geological hazards. This report represents a compilation of data collected from 1999 to 2003, including location and design of the monitoring sites, cone penetrometer borings, geologic logs, lithologic logs, geophysical logs, core analysis, water-chemistry analysis, ground-water-level measurements, and hydraulic and geomechanical properties from wells and core samples. Exploratory cone penetrometer borings taken in the upper 17 to 130 feet at six of the monitoring sites identified the base of Holocene as no deeper than 75 feet in the central confined area and no deeper than 35 feet in the southern unconfined areas of the valley. Generalized lithologic characterization from the monitoring sites indicates about four to six different aquifer units separated by relatively fine-grained units occur within the alluvial deposits shallower than 860 feet deep. Analysis of geophysical logs indicates that coarse-grained units varied in thickness between 10 and 25 feet in the southeastern unconfined area of the valley and between 50 and 200 feet in the south-central and southwestern areas of the valley. Deviations from temperature-gradient logs indicate that the majority of horizontal ground-water flow occurs above a depth of 775 feet in the south central and above 510 feet in the southeastern areas of the valley. Bulk physical properties from more than 1,150 feet of core samples indicate an average primary-wave velocity of about 5,515 feet per second, a bimodal distribution of density between 2.19 and 2.32 grams per cubic centimeter with an average of 2.16 grams per cubic centimeter, and a magnetic susceptibility that generally ranged between 9 and 40 with an average of 22. Water-chemistry data indicate that the ground water in the alluvial aquifers generally is low in total dissolved solids and chloride and of good quality. Isotopic data indicate that water from artificial recharge is present throughout the shallower parts of the aquifer system but may not be present toward the center of the valley. The percentage of water from artificial recharge present in ground water ranges from 0 to 61 percent for water-supply wells. The age of most shallow ground water is less than 2,000 years before present, and the age of deeper ground water is as much as 39,900 years before present, as determined from carbon age dates. Initial water-level data from the multiple-well monitoring sites indicate seasonal water-level fluctuations as great as 60 feet and water-level differences between aquifers as great as 10 feet. The water-level hydrographs indicate different water-level changes and relations between aquifers in different parts of the basin. However, most of these hydrographs indicate the potential for downward water-level gradients, with lower hydraulic heads in the deeper monitoring wells. Hydraulic properties of selected new monitoring wells indicate that horizontal hydraulic conductivities range from 0.1 to 583 feet per day. Hydraulic testing of selected core samples yielded vertical hydraulic conductivity values ranging from 8 x 10-4 to 0.3 feet per day, and effective porosity values ranging from 0.21 to 0.4. Geomechanical properties estimated from one-dimensional consolidation tests of selected core samples resulted in geometric mean inelastic and elastic specific storage values of 1.5 x 10-
Farrar, Christopher D.; Metzger, Loren F.; Nishikawa, Tracy; Koczot, Kathryn M.; Reichard, Eric G.; Langenheim, V.E.
2006-01-01
The Sonoma Valley, located about 30 miles north of San Francisco, is one of several basins in Sonoma County that use a combination of ground water and water delivered from the Russian River for supply. Over the past 30 years, Sonoma Valley has experienced rapid population growth and land-use changes. In particular, there has been a significant increase in irrigated agriculture, predominantly vineyards. To provide a better understanding of the ground-water/surface-water system in Sonoma Valley, the U.S. Geological Survey compiled and evaluated existing data, collected and analyzed new data, and developed a ground-water flow model to better understand and manage the ground-water system. The new data collected include subsurface lithology, gravity measurements, groundwater levels, streamflow gains and losses, temperature, water chemistry, and stable isotopes. Sonoma Valley is drained by Sonoma Creek, which discharges into San Pablo Bay. The long-term average annual volume of precipitation in the watershed is estimated to be 269,000 acre-feet. Recharge to the ground-water system is primarily from direct precipitation and Sonoma Creek. Discharge from the ground-water system is predominantly outflow to Sonoma Creek, pumpage, and outflow to marshlands and to San Pablo Bay. Geologic units of most importance for groundwater supply are the Quaternary alluvial deposits, the Glen Ellen Formation, the Huichica Formation, and the Sonoma Volcanics. In this report, the ground-water system is divided into three depth-based geohydrologic units: upper (less than 200 feet below land surface), middle (between 200 and 500 feet), and lower (greater than 500 feet). Synoptic streamflow measurements were made along Sonoma Creek and indicate those reaches with statistically significant gains or losses. Changes in ground-water levels in wells were analyzed by comparing historical contour maps with the contour map for 2003. In addition, individual hydrographs were evaluated to assess temporal changes by region. In recent years, pumping depressions have developed southeast of Sonoma and southwest of El Verano. Water-chemistry data for samples collected from 75 wells during 2002-04 indicate that the ground-water quality in the study area generally is acceptable for potable use. The water from some wells, however, contains one or more constituents in excess of the recommended standards for drinking water. The chemical composition of water from creeks, springs, and wells sampled for major ions plot within three groups on a trilinear diagram: mixed-bicarbonate, sodium-mixed anion, and sodium-bicarbonate. An area of saline ground water in the southern part of the Sonoma Valley appears to have shifted since the late 1940s and early 1950s, expanding in one area, but receding in another. Sparse temperature data from wells southwest of the known occurrence of thermal water suggest that thermal water may be present beneath a larger part of the valley than previously thought. Thermal water contains higher concentrations of dissolved minerals than nonthermal waters because mineral solubilities generally increase with temperature. Geohydrologic Characterization, Water-Chemistry, and Ground-Water Flow Simulation Model of the Sonoma Valley Area, Sonoma County, California Oxygen-18 (d18 O) and deuterium (dD) values for water from most wells plot along the global meteoric water line, indicating that recharge primarily is derived from the direct infiltration of precipitation or the infiltration of seepage from creeks. Samples from shallow- and intermediate-depth wells located near Sonoma Creek and (or) in the vicinity of Shellville plot to the right of the global meteoric water line, indicating that these waters are partly evaporated. The d18 O and dD composition of water from sampled wells indicates that water from wells deeper than 200 feet is isotopically lighter (more negative) than water from wells less than 200 feet deep, possibly indicating that older ground wate
Identifying the location and population served by domestic wells in California
Johnson, Tyler D.; Belitz, Kenneth
2015-01-01
Aggregating the results indicates that three hydrogeologic provinces contain nearly 80% of all domestic wells and also have the highest density of domestic well users: Central Valley (31.6%), Sierra Nevada (31.5%), and Northern Coast Ranges (16.6%). Results were also aggregated into groundwater basins and highland areas, collectively called Groundwater Units (GUs). Twenty-eight of the 938 GUs contain more than 50% of the total population served by domestic wells, 70 GUs contain more than 75%, and 150 GUs contain 90%. The 28 GUs are mostly located in the eastern and southern San Joaquin Valley (11), the Sacramento Valley (7), and the western foothills of the Sierra Nevada province (5). Using the information presented in this research along with other information about domestic-well use, the US Geological Survey has begun sampling high-use GUs for the Shallow Aquifer Assessment component of the Groundwater Ambient Assessment (GAMA) program.
Yavuz, Oguzhan; Valzacchi, Sandro; Hoekstra, Eddo; Simoneau, Catherine
2016-06-01
The aim of this study was the optimisation of a multi-analyte method for the analysis of primary aromatic amines (PAAs) from napkins in order to support official controls and food safety. We developed a UHPLC-MS/MS method for the simultaneous determination of 36 toxicologically relevant PAAs for paper and board. Good regression coefficients of the calibration curves in a range of 0.992-0.999 and reproducibilities in a range of 2.3-15% were obtained. Limits of detections (LODs) were in the range of 0.03-1.4 µg l(-1) and recoveries were in a range of 21-110% for all the amines. A total of 93 coloured paper napkin samples from different European countries were bought and extracted with water to determine the PAAs. The results showed that 42 of 93 samples contained at least one PAA. More than half of the detected PAAs are considered as toxic, carcinogenic or probably carcinogenic to humans by the International Agency for Research on Cancer (IARC), or are classified as such in the European Union legislation on chemicals. Summed concentrations of PAAs in seven samples were higher than 10 µg l(-1), the limit of summed PAA in the European Union plastic food contact material regulation. Also, eight PAAs, classified as Category 1A and 1B carcinogen in the European Union legislation of chemicals, were detected at concentrations higher than 2 µg l(-1), exceeding the limit proposed by the Federal Institute for Risk Assessment in Germany. Aniline (n = 14) was most frequently present in higher concentrations followed by o-toluidine, o-anisidine, 2,4-dimethylaniline and 4-aminoazobenzene. Red, orange, yellow and multicoloured paper napkins contained the highest concentrations of total PAAs (> 10 µg l(-1)). Although the European Union has not harmonised the legislation of paper and board materials and, thus, there is no specific migration limit for PAAs from paper napkins, the present study showed that coloured paper napkins can contain toxic and carcinogenic PAAs at concentrations that are relevant for monitoring.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alam, Ujjaini; Lasue, Jeremie, E-mail: ujjaini.alam@gmail.com, E-mail: jeremie.lasue@irap.omp.eu
We examine three SNe Type Ia datasets: Union2.1, JLA and Panstarrs to check their consistency using cosmology blind statistical analyses as well as cosmological parameter fitting. We find that the Panstarrs dataset is the most stable of the three to changes in the data, although it does not, at the moment, go to high enough redshifts to tightly constrain the equation of state of dark energy, w . The Union2.1, drawn from several different sources, appears to be somewhat susceptible to changes within the dataset. The JLA reconstructs well for a smaller number of cosmological parameters. At higher degrees ofmore » freedom, the dependence of its errors on redshift can lead to varying results between subsets. Panstarrs is inconsistent with the other two datasets at about 2σ confidence level, and JLA and Union2.1 are about 1σ away from each other. For the Ω{sub 0} {sub m} − w cosmological reconstruction, with no additional data, the 1σ range of values in w for selected subsets of each dataset is two times larger for JLA and Union2.1 as compared to Panstarrs. The range in Ω{sub 0} {sub m} for the same subsets remains approximately similar for all three datasets. We find that although there are differences in the fitting and correction techniques used in the different samples, the most important criterion is the selection of the SNe, a slightly different SNe selection can lead to noticeably different results both in the purely statistical analysis and in cosmological reconstruction. We note that a single, high quality low redshift sample could help decrease the uncertainties in the result. We also note that lack of homogeneity in the magnitude errors may bias the results and should either be modeled, or its effect neutralized by using other, complementary datasets. A supernova sample with high quality data at both high and low redshifts, constructed from a few surveys to avoid heterogeneity in the sample, and with homogeneous errors, would result in a more robust cosmological reconstruction.« less
Jones, Benjamin L; OʼHara, John P; Till, Kevin; King, Roderick F G J
2015-01-01
Fluid and sodium balance is important for performance and health; however, limited data in rugby union players exist. The purpose of the study was to evaluate body mass (BM) change (dehydration) and blood[Na] change during exercise. Data were collected from 10 premiership rugby union players, over a 4-week period. Observations included match play (23 subject observations), field (45 subject observations), and gym (33 subject observations) training sessions. Arrival urine samples were analyzed for osmolality, and samples during exercise were analyzed for [Na]. Body mass and blood[Na] were determined pre- and postexercise. Sweat[Na] was analyzed from sweat patches worn during exercise, and fluid intake was measured during exercise. Calculations of fluid and Na loss were made. Mean arrival urine osmolality was 423 ± 157 mOsm·kg, suggesting players were adequately hydrated. After match play, field, and gym training, BM loss was 1.0 ± 0.7, 0.3 ± 0.6, and 0.1 ± 0.6%, respectively. Fluid loss was significantly greater during match play (1.404 ± 0.977 kg) than field (1.008 ± 0.447 kg, p = 0.021) and gym training (0.639 ± 0.536 kg, p < 0.001). Fluid intake was 0.955 ± 0.562, 1.224 ± 0.601, and 0.987 ± 0.503 kg during match play, field, and gym training, respectively. On 43% of observations, players were hyponatremic when BM increased, 57% when BM was maintained, and 35% when there was a BM loss of 0.1-0.9%. Blood[Na] was the representative of normonatremia when BM loss was >1.0%. The findings demonstrate that rugby union players are adequately hydrated on arrival, fluid intake is excessive compared with fluid loss, and some players are at risk of developing hyponatremia.
NASA Astrophysics Data System (ADS)
Bouabdellah, Mohammed; Boudchiche, Lahbib; Ouahhabi, Benali; Naciri, Tayeb
2008-12-01
Sulfur isotope data measured on samples of galena from the main Mississippi Valley-type prospects of the eastern Beni Snassen belt preclude an igneous source for sulfur, pointing instead to a sedimentary source. Negative δ 34S values are interpreted to being derived from bacteriogenic reduction of Jurassic seawater sulphate. Positive δ 34S values are considered to be hydrothermal sulfide transported with metal-bearing fluid. Mixing of these two fluids resulted in the deposition of the Pb ore.
Ali, Usman; Ahmed, Khawaja Bashrat; Awan, Muhammad Siddique; Asraf, Shaid; Basher, Mohammad; Awan, Mohammad Naeem
2007-09-15
Nine months field survey was conducted from July 2004 to August 2005 to take the data on the distribution and population status of Himalayan ibex (Capra ibex sibirica) in the upper Neelum valley of Azad Kashmir. Survey was carried out using direct (senses) as well as indirect (sampling) methods. 122 animals of different categories were recorded in the study area. Total average population was composed of 31.79% male, 32.79% female, 25.41% young and 9.84% yearling animals. Various threats to the population of ibex in the area were also studied.
Origin and Evolution of Li-rich Brines at Clayton Valley, Nevada, USA
NASA Astrophysics Data System (ADS)
Munk, L. A.; Bradley, D. C.; Hynek, S. A.; Chamberlain, C. P.
2011-12-01
Lithium is the key component in Li-ion batteries which are the primary energy storage for electric/hybrid cars and most electronics. Lithium is also an element of major importance on a global scale because of interest in increasing reliance on alternative energy sources. Lithium brines and pegmatites are the primary and secondary sources, respectively of all produced Li. The only Li-brine in the USA that is currently in production exists in Clayton Valley, NV. The groundwater brines at Clayton Valley are located in a closed basin with an average evaporation rate of 142 cm/yr. The brines are pumped from six aquifer units that are composed of varying amounts of volcanic ash, gravel, salt, tufa, and fine-grained sediments. Samples collected include spring water, fresh groundwater, groundwater brine, and meteoric water (snow). The brines are classified as Na-Cl waters and the springs and fresh groundwater have a mixed composition and are more dilute than the brines. The Li content of the waters in Clayton Valley ranges from less than 1 μg/L (snow) up to 406.9 mg/L in the lower ash aquifer system (one of six aquifers in the basin). The cold springs surrounding Clayton Valley have Li concentrations of about 1 mg/L. A hot spring located just east of Clayton Valley contains 1.6 mg/L Li. The Li concentration of the fresh groundwater is less than 1 mg/L. Hot groundwater collected in the basin contain 30-40 mg/L Li. Water collected from a geothermal drilling north of Silver Peak, NV, had water with 4.9 mg/L Li at a depth of >1000m. The δD and δ18O isotopic signatures of fresh groundwater and brine form an evaporation path that extends from the global meteoric water line toward the brine from the salt aquifer system (the most isotopically enriched brine with ave. δD = -3.5, ave. δ18O = -67.0). This suggests that mixing of inflow water with the salt aquifer brine could have played an important role in the evolution of the brines. Along with mixing, evaporation appears to be an important process in the brine evolution. This is evident because of the increase in Na concentration as a function of enrichment in δD for most brine samples. In contrast the non-brine waters flowing into the basin show an increase in Na at relatively constant δD indicating little evaporation. The δD of clays sampled throughout a sediment core extending to 354 m below the surface show fluctuations that likely indicate warmer and cooler periods through time. Further investigation of the relationship of past climate and Li accumulation is in progress.
Ward, Tony J; Lincoln, Emily
2006-04-01
Throughout August and September, 2003, wildfires burned in close proximity to Missoula, Montana, with smoke emanating from the fires impacting the valley for much of the summer. This presented the perfect opportunity to measure the levels of polychlorinated dibenzodioxins and dibenzofurans (PCDD/F) comprising ambient forest fire smoke particles impacting the Missoula Valley. An air sampler at the Montana Department of Environmental Quality's (DEQ) compliance site in Missoula measured hourly averages of PM(10) throughout the fire season. Three collocated PM(2.5) cyclones collected 24-h smoke samples using quartz filters and Polyurethane Foam (PUF) sorbent cartridges. From the quartz filters, concentrations of Organic and Elemental Carbon (OC/EC) were measured, while PCDD/F were measured from one set of a filter (particle phase) and PUF (vapor phase) aggregate of samples in an attempt to also investigate the different phases of PCDD/F in forest fire smoke impaired communities. Hourly PM(10) concentrations peaked at 302.9 microg m(-3) on August 15. The highest OC concentration (115.6 microg m(-3)) was measured between August 21-22, and the highest EC concentration of 10.5 microg m(-3) was measured August 20-21. Measurable concentrations of PM(2.5) associated PCDD/Fs were not detected from a representative aggregate sample, with the exception of small amounts of 1,2,3,4,6,7,8-heptachlorodibenzodioxin and octachlorodibenzodioxin. PM(2.5) samples collected during the smoke events were composed of approximately 65% OC. However, the OC fraction of the particles collected in the smoke impaired Missoula valley was not composed of significant amounts of PCDD/F.
Temporal trends in nitrate and selected pesticides in mid-atlantic ground water
Debrewer, L.M.; Ator, S.W.; Denver, J.M.
2008-01-01
Evaluating long-term temporal trends in regional ground-water quality is complicated by variable hydrogeologic conditions and typically slow flow, and such trends have rarely been directly measured. Ground-water samples were collected over near-decadal and annual intervals from unconfined aquifers in agricultural areas of the Mid-Atlantic region, including fractured carbonate rocks in the Great Valley, Potomac River Basin, and unconsolidated sediments on the Delmarva Peninsula. Concentrations of nitrate and selected pesticides and degradates were compared among sampling events and to apparent recharge dates. Observed temporal trends are related to changes in land use and chemical applications, and to hydrogeology and climate. Insignificant differences in nitrate concentrations in the Great Valley between 1993 and 2002 are consistent with relatively steady fertilizer application during respective recharge periods and are likely related to drought conditions in the later sampling period. Detecting trends in Great Valley ground water is complicated by long open boreholes characteristic of wells sampled in this setting which facilitate significant ground-water mixing. Decreasing atrazine and prometon concentrations, however, reflect reported changes in usage. On the Delmarva Peninsula between 1988 and 2001, median nitrate concentrations increased 2 mg per liter in aerobic ground water, reflecting increasing fertilizer applications. Correlations between selected pesticide compounds and apparent recharge date are similarly related to changing land use and chemical application. Observed trends in the two settings demonstrate the importance of considering hydrogeology and recharge date along with, changing land and chemical uses when interpreting trends in regional ground-water quality. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
Butler, D.L.; Wright, W.G.; Stewart, K.C.; Osmundson, B.C.; Krueger, R.P.; Crabtree, D.W.
1996-01-01
In 1985, the U.S. Department of the Interior began a program to study the effects of irrigation drainage in the Western United States. These studies were done to determine whether irrigation drainage was causing problems related to human health, water quality, and fish and wildlife resources. Results of a study in 1991-93 of irrigation drainage associated with the Uncompahgre Project area, located in the lower Gunnison River Basin, and of the Grand Valley, located along the Colorado River, are described in this report. The focus of the report is on the sources, distribution, movement, and fate of selenium in the hydrologic and biological systems and the effects on biota. Generally, other trace- constituent concentrations in water and biota were not elevated or were not at levels of concern. Soils in the Uncompahgre Project area that primarily were derived from Mancos Shale contained the highest concentrations of total and watrer-extractable selenium. Only 5 of 128\\x11alfalfa samples had selenium concentrations that exceeded a recommended dietary limit for livestock. Selenium data for soil and alfalfa indicate that irrigation might be mobilizing and redistributing selenium in the Uncompahgre Project area. Distribution of dissolved selenium in ground water is affected by the aqueous geochemical environment of the shallow ground- water system. Selenium concentrations were as high as 1,300\\x11micrograms per liter in water from shallow wells. The highest concentrations of dissolved selenium were in water from wells completed in alluvium overlying the Mancos Shale of Cretaceous age; selenium concentrations were lower in water from wells completed in Mancos Shale residuum. Selenium in the study area could be mobilized by oxidation of reduced selenium, desorption from aquifer sediments, ion exchange, and dissolution. Infiltration of irrigation water and, perhaps nitrate, provide oxidizing conditions for mobilization of selenium from alluvium and shale residuum and for transport to streams and irrigation drains that are tributary to the Gunnison, Uncompahgre, and Colorado Rivers. Selenium concentrations in about 64\\x11percent of water samples collected from the lower Gunnison River and about 50 percent of samples from the Colorado River near the Colorado-Utah State line exceeded the U.S.\\x11Environmental Protection Agency criterion of 5\\x11micrograms per liter for protection of aquatic life. Almost all selenium concentrations in samples collected during the nonirrigation season from Mancos Shale areas exceeded the aquatic-life criterion. The maximum selenium concentrations in surface-water samples were 600\\x11micrograms per liter in the Uncompahgre Project area and 380\\x11micrograms per liter in the Grand Valley. Irrigation drainage from the Uncompahgre Project and the Grand Valley might account for as much as 75 percent of the selenium load in the Colorado River near the Colorado-Utah State line. The primary source areas of selenium were the eastern side of the Uncompahgre Project and the western one-half of the Grand Valley, where there is extensive irrigation on soils derived from Mancos Shale. The largest mean selenium loads from tributary drainages were 14.0 pounds per day from Loutsenhizer Arroyo in the Uncompahgre Project and 12.8 pounds per day from Reed Wash in the Grand Valley. Positive correlations between selenium loads and dissolved-solids loads could indicate that salinity-control projects designed to decrease dissolved-solids loads also could decrease selenium loads from the irrigated areas. Selenium concentrations in irrigation drainage in the Grand Valley were much higher than concentrations predicted by simple evaporative concentration of irrigation source water. Selenium probably is removed from pond water by chemical and biological processes and incorporated into bottom sediment. The maximum selenium concentration in bottom sediment was 47 micrograms per gram from a pond on the eastern side of the
Determination of patulin in apple juice by liquid chromatography: collaborative study.
Brause, A R; Trucksess, M W; Thomas, F S; Page, S W
1996-01-01
An AOAC International-International Union of Pure and Applied Chemistry-International Fruit Juice Union (AOAC-IUPAC-IFJU) collaborative study was conducted to evaluate a liquid chromatographic (LC) procedure for determination of patulin in apple juice. Patulin is a mold metabolite found naturally in rotting apples. Patulin is extracted with ethyl acetate, treated with sodium carbonate solution, and determined by reversed-phase LC with UV detection at 254 or 276 nm. Water, water-tetrahydrofuran, or water-acetonitrile was used as mobile phase. Levels determined in spiked test samples were 20, 50, 100, and 200 micrograms/L. A test sample naturally contaminated at 31 micrograms/L was also included. Twenty-two collaborators in 10 countries analyzed 12 test samples of apple juice. Recoveries averaged 96%, with a range of 91-108%. Repeatability relative standard deviations (RSDr) ranged from 10.9 to 53.8%. The reproducibility relative standard deviation (RSDR) ranged from 15.1 to 68.8%. The LC method for determination of patulin in apple juice has been adopted first action by AOAC INTERNATIONAL.
Omar, Jone; Slowikowski, Boleslaw; Boix, Ana; von Holst, Christoph
2017-08-01
Feed additives need to be authorised to be placed on the market according to Regulation (EU) No. 1831/2003. Next to laying down the procedural requirements, the regulation creates the European Union Reference Laboratory for Feed Additives (EURL-FA) and requires that applicants send samples to the EURL-FA. Once authorised, the characteristics of the marketed feed additives should correspond to those deposited in the sample bank of the EURL-FA. For this purpose, the submitted samples were subjected to near-infrared (NIR) and Raman spectroscopy for spectral characterisation. These techniques have the valuable potential of characterising the feed additives in a non-destructive manner without any complicated sample preparation. This paper describes the capability of spectroscopy for a rapid characterisation of products to establish whether specific authorisation criteria are met. This study is based on the analysis of feed additive samples from different categories and functional groups, namely products containing (1) selenium, (2) zinc and manganese, (3) vitamins and (4) essential oils such as oregano and thyme oil. The use of chemometrics turned out to be crucial, especially in cases where the differentiation of spectra by visual inspection was very difficult.
Hydrogeology and water quality of the West Valley Creek Basin, Chester County, Pennsylvania
Senior, Lisa A.; Sloto, Ronald A.; Reif, Andrew G.
1997-01-01
The West Valley Creek Basin drains 20.9 square miles in the Piedmont Physiographic Province of southeastern Pennsylvania and is partly underlain by carbonate rocks that are highly productive aquifers. The basin is undergoing rapid urbanization that includes changes in land use and increases in demand for public water supply and wastewater disposal. Ground water is the sole source of supply in the basin.West Valley Creek flows southwest in a 1.5-mile-wide valley that is underlain by folded and faulted carbonate rocks and trends east-northeast, parallel to regional geologic structures. The valley is flanked by hills underlain by quartzite and gneiss to the north and by phyllite and schist to the south. Surface water and ground water flow from the hills toward the center of the valley. Ground water in the valley flows west-southwest parallel to the course of the stream. Seepage investigations identified losing reaches in the headwaters area where streams are underlain by carbonate rocks and gaining reaches downstream. Tributaries contribute about 75 percent of streamflow. The ground-water and surface-water divides do not coincide in the carbonate valley. The ground-water divide is about 0.5 miles west of the surface-water divide at the eastern edge of the carbonate valley. Underflow to the east is about 1.1 inches per year. Quarry dewatering operations at the western edge of the valley may act partly as an artificial basin boundary, preventing underflow to the west. Water budgets for 1990, a year of normal precipitation (45.8 inches), and 1991, a year of sub-normal precipitation (41.5 inches), were calculated. Streamflow was 14.61 inches in 1990 and 12.08 inches in 1991. Evapotranspiration was estimated to range from 50 to 60 percent of precipitation. Base flow was about 62 percent of streamflow in both years. Exportation by sewer systems was about 3 inches from the basin and, at times, equaled base flow during the dry autumn of 1991. Recharge was estimated to be 18.5 inches in 1990 and 13.7 inches in 1991. Ground-water quality in the basin reflects differences in lithology and has been affected by human activities. Ground water in the carbonate rocks is naturally hard, has a near neutral pH, and contains more dissolved solids and less dissolved iron, manganese, and radon-222 than ground water in the noncarbonate rocks, which is soft, with moderately acidic to acidic pH. Regional contamination by chloride and nitrate and local contamination by organic compounds and metals was detected. Natural background concentrations are estimated to be about 1 milligram per liter for nitrate as nitrogen and less than 3 milligrams per liter for chloride. Ground water in unsewered areas and agricultural areas of the basin has median concentrations of nitrate that are greater than those in ground water from other areas; septic system effluent and fertilizer are probable sources of elevated nitrate. Water samples from wells in urbanized areas contain greater concentrations of chloride than samples from wells in residential areas; road salt is the probable source of elevated chloride. Organic solvents, especially trichloroethylene, were detected in 30 percent of the wells sampled in the urbanized carbonate valley. Most of the organic solvents and some of the metals in ground water were detected near old industrial sites.Base-flow stream quality of West Valley Creek was determined at 15 sites from monthly sampling for 1 year. Differences in stream quality reflect differences in lithology, land use, and point sources in tributary subbasins and mainstem reaches. The chemical composition of base flow in the mainstem is dominated by ground-water discharge from carbonate rocks. Elevated concentrations of nitrate (greater than 3 milligrams per liter as nitrogen) in base flow were measured in a tributary draining agricultural land and in a tributary draining an unsewered residential area. Elevated concentrations of phosphate (greater than 0.5 milligrams per liter as phosphorus) were measured in a stream that receives treated sewage effluent. Discharge of water containing elevated sulfate (about 250 milligrams per liter) from quarry dewatering operations contributes to die increase in sulfate concentration (of 10 to 40 milligrams per liter) in base flow downstream from the quarry. The chloride load at all stream sites is greater than the load contributed by precipitation and mineral weathering to the basin, indicating anthropogenic sources of chloride throughout the basin. The diversity index of the benthic invertebrate community has increased since 1973 at the longterm biological monitoring site on West Valley Creek, indicating an improvement in stream quality. The improvement probably is related to controls on discharges and banning of pesticides, such as DOT, in the 1970's. Concentrations of dissolved constituents, except for chloride, determined for base flow in the autumn do not appear to have changed since 1971. Application of the seasonal Kendall test for trend indicates that concentrations of chloride in base flow have increased since 1971; this increase may be related to the increase in urbanization in the basin. The benthic community structure at the West Valley Creek site in 1991 indicates slight nutrient enrichment.Lithium was detected in ground water and surface water downgradient from two lithiumprocessing facilities. Until 1991, lithium was discharged into a losing reach of West Valley Creek, thus introducing lithium into the ground-water system. The potential for cross-contamination between the ground-water and surface-water systems is great, as demonstrated by the detection of lithium in ground water and surface water downstream and downgradient from the two lithium-processing facilities. The lithium that was discharged into the creek acts as a conservative tracer in gaining reaches of West Valley Creek, maintaining a mass balance and characteristic isotopic signature. Lithium-7/lithium-6 ratios were greater in streams that are affected by sewage and by lithium-processing discharges and in ground water downgradient from the lithium-processing facilities than natural background lithium isotopic ratios.
NASA Astrophysics Data System (ADS)
López-Berdonces, Miguel; Fernandez-Calderón, Sergio; Higueras, Pablo; María Esbrí, Jose; Gonzalez-Corrochano, Beatríz; García-Noguero, Eva Mª; Martínez-Coronado, Alba; García-Noguero, Carolina
2013-04-01
Regional soil geochemistry in the Ojailén Valley: a realm dominated by the industrial and mining city of Puertollano (South Central Spain). Authors: Miguel A. López-Berdonces¹; Sergio Fernández Calderón¹; Pablo Higueras¹; José María Esbrí¹; Beatriz González-Corrochano¹; Eva Mª García-Noguero¹; Alba Martínez-Coronado¹; Carolina García Noguero¹ ¹Instituto de Geología Aplicada, Universidad de Castilla La Mancha, Almadén 13400 (Spain). Ojailén Valley is situated in South Central of Spain, an area where livestock, agriculture, mining and industry coexist. This work tries to assess the relationships between these activities and local environmental compartments: water, soils and heavy metal contents, and establish the most appropriate methodology of sample treatment and analytical techniques that can be employed on this kind of studies. For soil geochemistry, 152 samples were taken at two different depths, one at surface layer and another at 20 cm depth, and establish relationships between them and the possible sources. For this purpose, we determine soil parameters (pH, conductivity and organic matter) and total metal contents by Energy Dispersion of X Ray Fluorescence (EDXRF). Samples with higher nickel contents were analyzed with Inductive Coupled Plasma Spectroscopy (ICP-OES) after acid digestion. The study of surface waters includes 18 samples along the river and tributaries near mining and industrial areas. Water analysis was performed by ICP-OES. Soil samples shows pH between 6 and 8.5, highest located near on the east part of the valley, in the vicinity of petrochemical complex. Conductivity values show higher levels (1600 µS cm¯¹) in the vicinity of Puertollano and the industrial sites. Local reference value (LRV) for contaminated soils were determined according to the methodology proposed by Jimenez-Ballesta et al. (2010), using the equation: LRV=GM + 2SD, where LRV: Local Reference Value, GM: Geometric Mean, SD: Standard Deviation. Trace metals values are significantly higher than calculated LRV, especially for Zn, Pb, (Average content: 230 mg kg¯¹ and 249.9 mg kg¯¹ respectively), probable due to Pb-Zn mining in the nearest Alcudia valley. Other elements seem to be influenced by petrochemical industry (Ni, V, and Cu) with LRV: 199.9 mg kg¯¹, 39.2 mg kg¯¹ and 184.2 mg kg¯¹ respectively. Most water samples have metal contents higher than levels for drinking water (WHO, 2006), especially Fe and Pb with 20 µg l¯¹ and 10 µg l¯¹ respectively. Higher metal contents were located on three different sites: downstream an open-pit coal mine, in stagnant water where we can find an old sewage treatment plant, and downstream a photovoltaic plant built in 2008. We can consider that Ojailén Valley is not an area with high contents in heavy metals in the environment, but Puertollano and its petrochemical complex have contents in Pb, Zn, Cu, As, Ni above the LRV. A comparison of results obtained by ICP-MS and XRF related to Pb, Zn, Cr, Ni in thirty-four selected samples, we can conclude that both techniques are qualitatively agree, although XRF cannot be considered suitable for establishing reference legal limits. References Jiménez-Ballesta, R; Conde-Bueno,P; Martin-Rubí,J.A.; García-Jímenez,R. 2010. Geochemical baseline contents levels and soil quality reference values of trace elements in soils from the Mediterranean (Castilla-La Mancha, Spain). Central European Journal of Geosciences 2, 441-454. WHO2006. Guidelines for drinking- water quality, Vol.1, 3rd edition incorporating 1st and 2nd addenda. (http//www.who.int/entity/water_sanitation_health/dwq/fulltext.pdf) Geneve, Suiza.
Aeromagnetic maps with geologic interpretations for the Tularosa Valley, south-central New Mexico
Bath, G.D.
1977-01-01
An aeromagnetic survey of the Tularosa Valley in south-central New Mexico has provided information on the igneous rocks that are buried beneath alluvium and colluvium. The data, compiled as residual magnetic anomalies, are shown on twelve maps at a scale of 1:62,500. Measurements of magnetic properties of samples collected in the valley and adjacent highlands give a basis for identifying the anomaly-producing rocks. Precambrian rocks of the crystalline basement have weakly induced magnetizations and produce anomalies having low magnetic intensities and low magnetic gradients. Late Cretaceous and Cenozoic intrusive rocks have moderately to strongly induced magnetizations. Precambrian rocks produce prominent magnetic anomalies having higher amplitudes and higher gradients. The Quaternary basalt has a strong remanent magnetization of normal polarity and produces narrow anomalies having high-magnetic gradients. Interpretations include an increase in elevation to the top of buried Precambrian rock in the northern part of the valley, a large Late Cretaceous and Cenozoic intrusive near Alamogordo, and a southern extension of the intrusive rock exposed in the Jarilla Mountains. Evidence for the southern extension comes from a quantitative analysis of the magnetic anomalies..
Bennett, George L.; Fram, Miranda S.; Belitz, Kenneth
2011-01-01
Groundwater quality in the Southern, Middle, and Northern Sacramento Valley study units was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study units are located in California's Central Valley and include parts of Butte, Colusa, Glenn, Placer, Sacramento, Shasta, Solano, Sutter, Tehama, Yolo, and Yuba Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The three study units were designated to provide spatially-unbiased assessments of the quality of untreated groundwater in three parts of the Central Valley hydrogeologic province, as well as to provide a statistically consistent basis for comparing water quality regionally and statewide. Samples were collected in 2005 (Southern Sacramento Valley), 2006 (Middle Sacramento Valley), and 2007-08 (Northern Sacramento Valley). The GAMA studies in the Southern, Middle, and Northern Sacramento Valley were designed to provide statistically robust assessments of the quality of untreated groundwater in the primary aquifer systems that are used for drinking-water supply. The assessments are based on water-quality data collected by the USGS from 235 wells in the three study units in 2005-08, and water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer systems (hereinafter, referred to as primary aquifers) assessed in this study are defined by the depth intervals of the wells in the CDPH database for each study unit. The quality of groundwater in shallow or deep water-bearing zones may differ from quality of groundwater in the primary aquifers; shallow groundwater may be more vulnerable to contamination from the surface. The status of the current quality of the groundwater resource was assessed by using data from samples analyzed for volatile organic compounds (VOC), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifers of the three Sacramento Valley study units, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by benchmark concentrations) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than 1.0 indicates a concentration greater than a benchmark. For organic (volatile organic compounds and pesticides) and special-interest (perchlorate) constituents, relative-concentrations were classified as high (greater than 1.0); moderate (equal to or less than 1.0 and greater than 0.1); or low (equal to or less than 0.1). For inorganic (major ion, trace element, nutrient, and radioactive) constituents, the boundary between low and moderate relative-concentrations was set at 0.5. Aquifer-scale proportions were used in the status assessment for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifers that have a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentage of the primary aquifers that have moderate and low relative-concentrations, respectively. Two statistical approaches-grid-based, which used one value per grid cell, and spatially-weighted, which used the full dataset-were used to calculate aquifer-scale proportions for individual constituents and classes of constituents. High and moderate aquifer-scale proportions were significantly greater for inorgani
Cannon, M.R.
1987-01-01
Federal coal lands of the Woodson Preference Right Lease Application are located in Dawson and Richland Counties, northeastern Montana. A probable mine area, comprised of the lease area and adjacent coal lands, contains about 220 million tons of recoverable lignite coal in the 12-37 ft thick Pust coal bed. A hydrologic study has been conducted in the area to describe the water resources and to evaluate potential effects of coal mining on the water resources. Geohydrologic data collected from wells and springs indicate that several aquifers exist in the area. Sandstone beds in the Tongue River Member of the Fort Union Formation (Paleocene age) are the most common aquifers and probably underlie the entire area. The Pust coal bed in the Tongue River Member is water saturated in part of the probable mine area and is dry in other parts of the probable mine area. Other aquifers, located mostly outside of the probable mine area, exist in gravel of the Flaxville Formation (Miocene of Pliocene age) and valley alluvium (Pleistocene and Holocene age). Chemical analyses of groundwater indicate a range in dissolved solids concentration of 240-2,280 mg/L. Surface water resources are limited. Most streams in the area are ephemeral and flow only in response to rainfall or snowmelt. Small reaches of the North and Middle Forks of Burns Creek have intermittent flow. Water sampled from a small perennial reach of the Middle Fork had a dissolved solids concentration of 700 mg/L. Mining of the Pust coal bed would destroy one spring and four stock wells, dewater areas of the Pust coal and sandstone aquifers, and probably lower water levels in seven stock and domestic wells. Mining in the valley of Middle Fork Burns Creek would intercept streamflow and alter flow characteristics of a small perennial reach of stream. Leaching of soluble minerals from mine spoils may cause a long-term degradation of the quality of water in the spoils and in aquifers downgradient from the spoils. Some of the effects on local water supplies could be mitigated by development of new wells in deeper sandstones of the Tongue River Member. Effects of mining on water resources would be minimized if only areas of dry coal were mined. (Author 's abstract)
NASA Astrophysics Data System (ADS)
Engel, Zbyněk; Mentlík, Pavel; Braucher, Régis; Křížek, Marek; Pluháčková, Markéta; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim; Aster Team; Arnold, Maurice; Aumaître, Georges; Bourlès, Didier; Keddadouche, Karim
2017-09-01
10Be exposure ages from moraines and bedrock sites in the Roháčská Valley provide chronology of the last glaciation in the largest valley of the Western Tatra Mts., the Western Carpathians. The minimum apparent exposure age of 19.4 ± 2.1 ka obtained for the oldest sampled boulder and the mean age of 18.0 ± 0.8 ka calculated for the terminal moraine indicate that the oldest preserved moraine was probably deposited at the time of the global Last Glacial Maximum (LGM). The age of this moraine coincides with the termination of the maximum glacier expansion in other central European ranges, including the adjacent High Tatra Mts. and the Alps. The equilibrium line altitude (ELA) of the LGM glacier in the Roháčská Valley, estimated at 1400-1410 m a.s.l., was 50-80 m lower than in the eastern part of the range, indicating a positive ELA gradient from west to east among the north-facing glaciers in the Tatra Mts. Lateglacial glacier expansion occurred no later than 13.4 ± 0.5 ka and 11.9 ± 0.5 ka, as indicated by the mean exposure ages calculated for re-advance moraines. This timing is consistent with the exposure age chronology of the last Lateglacial re-advance in the High Tatra Mts., Alps and lower mountain ranges in central Europe. The ELA in the Roháčská Valley estimated at 1690-1770 m a.s.l. in this period was located 130-300 m lower than in the north-facing valleys in the High Tatra Mts. 10Be exposure ages obtained for a rock glacier constrains the timing of this landform stabilization in the Salatínska Valley and provides the first chronological evidence for the Lateglacial activity of rock glaciers in the Carpathians.
NASA Astrophysics Data System (ADS)
Seki, Kaori; Kanda, Wataru; Tanbo, Toshiya; Ohba, Takeshi; Ogawa, Yasuo; Takakura, Shinichi; Nogami, Kenji; Ushioda, Masashi; Suzuki, Atsushi; Saito, Zenshiro; Matsunaga, Yasuo
2016-10-01
This study clarifies the hydrothermal system of Jigokudani Valley near Mt. Tateyama volcano in Japan by using a combination of audio-frequency magnetotelluric (AMT) survey and hot-spring water analysis in order to assess the potential of future phreatic eruptions in the area. Repeated phreatic eruptions in the area about 40,000 years ago produced the current valley morphology, which is now an active solfatara field dotted with hot springs and fumaroles indicative of a well-developed hydrothermal system. The three-dimensional (3D) resistivity structure of the hydrothermal system was modeled by using the results of an AMT survey conducted at 25 locations across the valley in 2013-2014. The model suggests the presence of a near-surface highly conductive layer of < 50 m in thickness across the entire valley, which is interpreted as a cap rock layer. Immediately below the cap rock is a relatively resistive body interpreted as a gas reservoir. Field measurements of temperature, pH, and electrical conductivity (EC) were taken at various hot springs across the valley, and 12 samples of hot-spring waters were analyzed for major ion chemistry and H2O isotopic ratios. All hot-spring waters had low pH and could be categorized into three types on the basis of the Cl-/SO 42 - concentration ratio, with all falling largely on a mixing line between magmatic fluids and local meteoric water (LMW). The geochemical analysis suggests that the hydrothermal system includes a two-phase zone of vapor-liquid. A comparison of the resistivity structure and the geochemically inferred structure suggests that a hydrothermal reservoir is present at a depth of approximately 500 m, from which hot-spring water differentiates into the three observed types. The two-phase zone appears to be located immediately beneath the cap rock structure. These findings suggest that the hydrothermal system of Jigokudani Valley exhibits a number of factors that could trigger a future phreatic eruption.
NASA Astrophysics Data System (ADS)
Pensa, Alessandra; Capra, Lucia; Giordano, Guido; Corrado, Sveva
2018-05-01
The recent 10th-11th of July 2015 Volcán de Colima eruption involved the collapse of the summit dome that breached to the south generating pyroclastic density currents (PDCs) along the Montegrande ravine on the southern flank of the volcano. Trees within the valley were buried, uprooted and variably transported by the PDCs, while the trees on the edges of the valley and on the overbanks, were mainly burned and folded. The emplacement temperature of valley confined and overbank PDC deposits were reconstructed using Partial Thermal Remanent Magnetization (pTRM) analysis of lithic clasts and Charcoal Reflectance analysis (Ro %) applied to the charred wood. A total of 13 sites were sampled for the pTRM study and 39 charcoaled wood fragments were collected for the charcoal optical analysis along the entire deposit length in order to detect temperature variation from proximal to distal zone. The result overlap from both data sets display a T max from ≃345°-385 °C in valley-confined area (from 3.5 to 8.5 km from the vent) and ≃170°-220 °C (from 8.0 to 10.5 km from the vent) in unconfined distal area. The emplacement temperature pattern along the 10.5 km long deposit appears related to the degree of topography confinement: valley confined and unconfined. In particular the valley confined setting is very conservative in terms of temperature, while the major drop occurs in a very narrow space where the PDC expanded over unconfined flat topography just at the exit of the main valley. This study represents the first attempt in determining the relationship between PDCs flow dynamics variation and topographic confining using deposit emplacement temperature as key proxy.
Examining the cosmic acceleration with the latest Union2 supernova data
NASA Astrophysics Data System (ADS)
Li, Zhengxiang; Wu, Puxun; Yu, Hongwei
2011-01-01
In this Letter, by reconstructing the Om diagnostic and the deceleration parameter q from the latest Union2 Type Ia Supernova sample with and without the systematic error along with the baryon acoustic oscillation (BAO) and the cosmic microwave background (CMB), we study the cosmic expanding history, using the Chevallier-Polarski-Linder (CPL) parametrization. We obtain that Union2+BAO favor an expansion with a decreasing of the acceleration at z<0.3. However, once the CMB data is added in the analysis, the cosmic acceleration is found to be still increasing, indicating a tension between low redshift data and high redshift. In order to reduce this tension significantly, two different methods are considered and thus two different subsamples of Union2 are selected. We then find that two different subsamples+BAO+CMB give completely different results on the cosmic expanding history when the systematic error is ignored, with one suggesting a decreasing cosmic acceleration, the other just the opposite, although both of them alone with BAO support that the cosmic acceleration is slowing down. However, once the systematic error is considered, two different subsamples of Union2 along with BAO and CMB all favor an increasing of the present cosmic acceleration. Therefore a clear-cut answer on whether the cosmic acceleration is slowing down calls for more consistent data and more reliable methods to analyze them.
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 structures that could affect groundwater flow between the groundwater basins in the study area, gravity data were collected using more closely spaced measurements in September 2014. Groundwater-level data was gathered and collected from March 2014 through March 2015 to determine depth to water and direction of groundwater flow. The gravity and groundwater-level data showed that the saturated thickness of the alluvium was about 2,000 feet thick to the east and about 130 feet thick above the northward-trending basement ridge near Llano, California. Although it was uncertain whether the basement ridge affects the groundwater system, a potential barrier to groundwater flow could be created if the water table fell below the altitude of the basement ridge, effectively causing the area to the west of the basement ridge to become hydraulically isolated from the area to the east. In addition, the direction of regional-groundwater flow likely will be influenced by future changes in the number and distribution of pumping wells and the thickness of the saturated alluvium from which water is withdrawn. Three-dimensional animations were created to help visualize the relation between the basins’ basement topography and the groundwater system in the area. Further studies that could help to more accurately define the basins and evaluate the groundwater-flow system include exploratory drilling of multi-depth monitoring wells; collection of depth-dependent water-quality samples; and linking together existing, but separate, groundwater-flow models from the Antelope Valley and El Mirage Valley groundwater basins into a single, calibrated groundwater-flow model.
Trevisi, R; Risica, S; D'Alessandro, M; Paradiso, D; Nuccetelli, C
2012-02-01
The authors set up a database of activity concentration measurements of natural radionuclides (²²⁶Ra, ²³²Th and ⁴⁰K) in building material. It contains about 10,000 samples of both bulk material (bricks, concrete, cement, natural- and phosphogypsum, sedimentary and igneous bulk stones) and superficial material (igneous and metamorphic stones) used in the construction industry in most European Union Member States. The database allowed the authors to calculate the activity concentration index I--suggested by a European technical guidance document and recently used as a basis for elaborating the draft Euratom Basic Safety Standards Directive--for bricks, concrete and phosphogypsum used in the European Union. Moreover, the percentage could be assessed of materials possibly subject to restrictions, if either of the two dose criteria proposed by the technical guidance were to be adopted. Copyright © 2011 Elsevier Ltd. All rights reserved.
Geochronology of Tropical Alpine Glaciations From the Cordillera Huayhuash, Peru
NASA Astrophysics Data System (ADS)
Hall, S. R.; Farber, D. L.; Rodbell, D. T.; Finkel, R. C.; Ramage, J. M.; Smith, J. A.; Mark, B. G.; Seltzer, G. O.
2004-12-01
The Cordillera Huayhuash of the Central Peruvian Andes (10.3° S, 76.9° W) is an ideal range to study regional climate signals and variations in paleo-ice volumes. Located between the Cordillera Blanca to the north and the Junin region to the south, the range trends nearly north-south with modern glaciers confined to the high peaks (>4800 m). Cross-cutting relationships, geomorphology, and correlation with surface exposure dated moraines in the nearby Cordillera Blanca suggest the region preserves a rich record of tropical glaciation. In order to determine the glacial chronology we mapped and dated glacial features of the Jahuacocha valley (which drains the western side of the range) and two eastern drainages, the Mitococha valley, and the Carhuacocha valley. At each locality we used ASTER data, aerial photographs, and GPS to map glacial features both within main valleys and tributaries. We sampled quartz-bearing erratics on moraine crests as well as ice-polished bedrock surfaces for exposure age dating using in situ produced cosmogenic 10Be and 26Al. In the Jahuacocha valley, the greatest ice extent reached an elevation of ˜4090m and moraine crest boulders yield and age of ˜11.2 ±0.6 ka suggesting a significant late Glacial ice advance or stillstand. A younger cluster of moraines exists ˜1 km up-valley at an elevation of ˜4100m. These moraines, dated at ˜8.0 ±1.0 ka, suggest an early Holocene advance. In the Mitococha valley, a young moraine and polished bedrock dated at ˜0.2 ka and ˜11.4 ±0.4 ka respectively span the late Glacial through recent. The late Glacial features of this eastern drainage occur at an elevation of ˜4100m while the recent events occur at an elevation of ˜4380m. Our preliminary results suggest that all three valleys experienced a very similar glacial history with minor differences likely due to the variations in valley morphology. Comparing the chronology of glaciation in the Cordillaera Huayhuash with that in regions to the south and north will provide a means of evaluating the degree of synchroneity of glaciation and climate change across 5° of latitude in the tropics.
McClymonds, N.E.
1984-01-01
Shallow aquifers exist primarily within the Tongue River Member of the Paleocene Fort Union Formation and within valley alluvium. Sandstone beds are the principal aquifers for domestic supply and livestock watering, with the Knobloch coal bed being a secondary source of supply. Surface-water resources consist principally of perennial flow in Otter Creek and intermittent flow in eight small drainage basins. The small streams are generally dry at their mouth, except after intense rainfall or sudden snowmelt. Otter Creek is used for livestock watering and, during spring floods, for irrigating alfalfa fields. The water supplied by wells generally is a sodium bicarbonate type. Dissolved-solids concentrations of water samples ranged from 480 to 3,460 milligrams per liter in sandstone beds and from 910 to 6,260 milligrams per liter in the Knobloch coal bed. Water in Otter Creek contains principally sodium, magnesium, and sulfate ions. The dissolved-solids concentration ranged from 2,050 to 2 ,950 milligrams per liter. Mining of the Knobloch coal bed would remove three private wells and adversely affect the yield of two other wells. After mining, water in the alluvium of Otter Creek might show long-term degradation in water quality as a result of waters leaching the soluble salts from the spoils material used to backfill the mine pits. Although mining would alter the existing hydrologic systems and remove several shallow wells, alternative ground-water supplies are available from deeper aquifers that could be developed to replace those lost by mining. (USGS)
Subsurface valleys and geoarcheology of the Eastern Sahara revealed by shuttle radar
McCauley, J.F.; Schaber, G.G.; Breed, C.S.; Grolier, M.J.; Haynes, C.V.; Issawi, B.; Elachi, C.; Blom, R.
1982-01-01
The shuttle imaging radar (SIR-A) carried on the space shuttle Columbia in November 1981 penetrated the extremely dry Selima Sand Sheet, dunes, and drift sand of the eastern Sahara, revealing previously unknown buried valleys, geologic structures, and possible Stone Age occupation sites. Radar responses from bedrock and gravel surfaces beneath windblown sand several centimeters to possibly meters thick delineate sand- and alluvium-filled valleys, some nearly as wide as the Nile Valley and perhaps as old as middle Tertiary. The nov-vanished maijor river systems that carved these large valleys probably accomplished most of the erosional stripping of this extraordinarily flat, hyperarid region. Underfit and incised dry wadis, many superimposed on the large valleys, represent erosion by intermittent running water, probably during Quaternary pluvials. Stone Age artifacts associated with soils in the alluvium suggest that areas near the wadis may have been sites of early human occupation. The presence of old drainage networks beneath the sand sheet provides a geologic explanation for the locations of many playas and present-day oases which have been centers of episodic human habitation. Radar penetration of dry sand and soils varies with the wavelength of the incident signals (24 centimeters for the SIR-A system), incidence angle, and the electrical properties of the materials, which are largely determined by moisture content. The calculated depth of radar penetration of dry sand and granules, based on laboratory measurements of the electrical properties of samples from the Selima Sand Sheet, is at least 5 meters. Recent (September 1982) field studies in Egypt verified SIR-A signal penetration depths of at least 1 meter in the Selima Sand Sheet and in drift sand and 2 or more meters in sand dunes. Copyright ?? 1982 AAAS.
Han, Liang; Hole, John; Stock, Joann; Fuis, Gary S.; Williams, Colin F.; Delph, Jonathan; Davenport, Kathy; Livers, Amanda
2016-01-01
Plate-boundary rifting between transform faults is opening the Imperial Valley of southern California and the rift is rapidly filling with sediment from the Colorado River. Three 65–90 km long seismic refraction profiles across and along the valley, acquired as part of the 2011 Salton Seismic Imaging Project, were analyzed to constrain upper crustal structure and the transition from sediment to underlying crystalline rock. Both first arrival travel-time tomography and frequency-domain full-waveform inversion were applied to provide P-wave velocity models down to ∼7 km depth. The valley margins are fault-bounded, beyond which thinner sediment has been deposited on preexisting crystalline rocks. Within the central basin, seismic velocity increases continuously from ∼1.8 km/s sediment at the surface to >6 km/s crystalline rock with no sharp discontinuity. Borehole data show young sediment is progressively metamorphosed into crystalline rock. The seismic velocity gradient with depth decreases approximately at the 4 km/s contour, which coincides with changes in the porosity and density gradient in borehole core samples. This change occurs at ∼3 km depth in most of the valley, but at only ∼1.5 km depth in the Salton Sea geothermal field. We interpret progressive metamorphism caused by high heat flow to be creating new crystalline crust throughout the valley at a rate comparable to the ≥2 km/Myr sedimentation rate. The newly formed crystalline crust extends to at least 7–8 km depth, and it is shallower and faster where heat flow is higher. Most of the active seismicity occurs within this new crust.
NASA Astrophysics Data System (ADS)
Mason, C. C.; Spotila, J. A.; Fame, M. L.; Dorsey, R. J.; Shuster, D. L.
2015-12-01
The Coachella Valley of southern California (USA) is a late Cenozoic transform-related sedimentary basin created by top-to-the-east extension on the West Salton detachment fault and dextral strike-slip offset on the San Andreas fault (Axen and Fletcher, 1998), which has continued to subside as a result of northeastward tilting since initiation of the San Jacinto fault ca. 1.2 Ma. Though it is generally agreed that these large regional faults are responsible for creation of high relief and deep subsidence in the Coachella Valley, the timing, magnitude, and geometries of fault offsets on these structures are still debated. This project applies an integrated source-to-sink approach to investigate tectonic models for evolution of the Pacific-North American plate boundary as recorded in the world-class natural laboratory of the Coachella Valley. In this study we integrate new thermochronometry-constrained kinematic models with tectonostratigraphic interpretations to help quantify the timing, rates, and magnitudes of tectonically driven vertical crustal motions and resulting mass fluxes. We sampled bedrock for U-Th/He (A-He) thermochronometry in the Mecca Hills, Santa Rosa, San Jacinto, and Little San Bernardino Mountains in both spatially focused and widely distributed areas. We also present new results from apatite 4/3He thermochronometry to help constrain the most recent exhumation histories. A-He results reveal spatially variable exhumation ages. The southwest Santa Rosa Mountains experienced late Miocene-early Pliocene exhumation along their southwest flank, while new A-He ages from ranges bounding Coachella Valley reveal complex uplift histories. We integrate our data set with previously published thermochronometric data to improve a regional synthesis of late Cenozoic vertical motions of the Coachella Valley.
Phylogeography of microbial phototrophs in the dry valleys of the high Himalayas and Antarctica.
Schmidt, S K; Lynch, R C; King, A J; Karki, D; Robeson, M S; Nagy, L; Williams, M W; Mitter, M S; Freeman, K R
2011-03-07
High-elevation valleys in dry areas of the Himalayas are among the most extreme, yet least explored environments on Earth. These barren, rocky valleys are subjected to year-round temperature fluctuations across the freezing point and very low availability of water and nutrients, causing previous workers to hypothesize that no photoautotrophic life (primary producers) exists in these locations. However, there has been no work using modern biogeochemical or culture-independent molecular methods to test the hypothesis that photoautotrophs are absent from high Himalayan soil systems. Here, we show that although microbial biomass levels are as low as those of the Dry Valleys of Antarctica, there are abundant microbial photoautotrophs, displaying unexpected phylogenetic diversity, in barren soils from just below the permanent ice line of the central Himalayas. Furthermore, we discovered that one of the dominant algal clades from the high Himalayas also contains the dominant algae in culture-independent surveys of both soil and ice samples from the Dry Valleys of Antarctica, revealing an unexpected link between these environmentally similar but geographically very distant systems. Phylogenetic and biogeographic analyses demonstrated that although this algal clade is globally distributed to other high-altitude and high-latitude soils, it shows significant genetic isolation by geographical distance patterns, indicating local adaptation and perhaps speciation in each region. Our results are the first to demonstrate the remarkable similarities of microbial life of arid soils of Antarctica and the high Himalayas. Our findings are a starting point for future comparative studies of the dry valleys of the Himalayas and Antarctica that will yield new insights into the cold and dry limits to life on Earth.
NASA Astrophysics Data System (ADS)
Han, Liang; Hole, John A.; Stock, Joann M.; Fuis, Gary S.; Williams, Colin F.; Delph, Jonathan R.; Davenport, Kathy K.; Livers, Amanda J.
2016-11-01
Plate-boundary rifting between transform faults is opening the Imperial Valley of southern California and the rift is rapidly filling with sediment from the Colorado River. Three 65-90 km long seismic refraction profiles across and along the valley, acquired as part of the 2011 Salton Seismic Imaging Project, were analyzed to constrain upper crustal structure and the transition from sediment to underlying crystalline rock. Both first arrival travel-time tomography and frequency-domain full-waveform inversion were applied to provide P-wave velocity models down to ˜7 km depth. The valley margins are fault-bounded, beyond which thinner sediment has been deposited on preexisting crystalline rocks. Within the central basin, seismic velocity increases continuously from ˜1.8 km/s sediment at the surface to >6 km/s crystalline rock with no sharp discontinuity. Borehole data show young sediment is progressively metamorphosed into crystalline rock. The seismic velocity gradient with depth decreases approximately at the 4 km/s contour, which coincides with changes in the porosity and density gradient in borehole core samples. This change occurs at ˜3 km depth in most of the valley, but at only ˜1.5 km depth in the Salton Sea geothermal field. We interpret progressive metamorphism caused by high heat flow to be creating new crystalline crust throughout the valley at a rate comparable to the ≥2 km/Myr sedimentation rate. The newly formed crystalline crust extends to at least 7-8 km depth, and it is shallower and faster where heat flow is higher. Most of the active seismicity occurs within this new crust.
NASA Astrophysics Data System (ADS)
Pearlstein, S.; Compton, J.; Eldridge, A.; Henning, A.; Selker, J. S.; Brooks, J. R.; Schmitz, D.
2016-12-01
Groundwater nitrate contamination affects thousands of households in the southern Willamette Valley and many more across the Pacific Northwest. The southern Willamette Valley Groundwater Management Area (SWV GWMA) was established in 2004 due to nitrate levels in the groundwater exceeding the human health standard of 10 mg nitrate-N L-1. Much of the nitrogen inputs to the GWMA comes from agricultural nitrogen use, and thus efforts to reduce N inputs to groundwater are focused upon improving N management. Previous work in the 1990s in the Willamette Valley by researchers at Oregon State University determined the importance of cover crops and irrigation practices and made recommendations to the local farm community for reducing nitrogen (N) leaching. We are currently re-sampling many of the same fields studied by OSU to examine the influence of current crops and nutrient management practices on nitrate leaching below the rooting zone. This study represents important crops currently grown in the GWMA and includes four grass fields, three vegetable row-crop fields, two peppermint and wheat fields, and one each of hazelnuts and blueberries. New nutrient management practices include slow release fertilizers and precision agriculture approaches in some of the fields. Results from the first two years of sampling show nitrate leaching is lower in some crops like row crops grown for seed and higher in others like perennial rye grass seed when compared to the 1990s data. We will use field-level N input-output balances in order to determine the N use efficiency and compare this across crops and over time. The goal of this project is to provide information and tools that will help farmers, managers and conservation groups quantify the water quality benefits of management practices they are conducting or funding.
Toscano, N C; Prabhaker, N; Castle, S J; Henneberry, T J
2001-12-01
A survey of 53 Bemisia argentifolii Bellows & Perring populations from different agricultural regions in California and Arizona was conducted from 1997 to 1999 to establish baseline toxicological responses to buprofezin and pyriproxyfen. Although both compounds proved to be highly toxic even in minute quantities to specific stages, geographical and temporal differences in responses were detected using a leaf spray bioassay technique. Monitoring for three years revealed that six to seven populations had higher LC50 values but not greater survival when exposed to these two insecticides. A significant difference in relative susceptibility to buprofezin was first observed in late season 1997 in San Joaquin Valley populations with LC50s ranging from 16 to 22 microg (AI)/liter(-1) compared with IC50s of 1 to 3 mg (AI)/liter(-1) in Imperial, Palo Verde Valley and Yuma populations. Whiteflies collected in subsequent years from these and other locations showed an increase in susceptibility to buprofezin. Regional differences in susceptibilities to pyriproxyfen were minimal within the same years. Three years of sampling revealed consistently higher LC50s to pyriproxyfen in populations from Palo Verde Valley, CA, compared with whiteflies from Imperial, San Joaquin Valley or Yuma. As was the case with buprofezin, a decline in LC50s to pyriproxyfen was observed in whiteflies from all locations sampled in 1999. However, no correlation was observed between buprofezin and pyriproxyfen toxicity in any of the strains. The variable toxicities observed to both compounds over a period of 3 yr may be due principally to inherent differences among geographical populations or due to past chemical use which may confer positive or negative cross-resistance to buprofezin or pyriproxyfen.
Estimation of Groundwater Recharge at Pahute Mesa using the Chloride Mass-Balance Method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cooper, Clay A; Hershey, Ronald L; Healey, John M
Groundwater recharge on Pahute Mesa was estimated using the chloride mass-balance (CMB) method. This method relies on the conservative properties of chloride to trace its movement from the atmosphere as dry- and wet-deposition through the soil zone and ultimately to the saturated zone. Typically, the CMB method assumes no mixing of groundwater with different chloride concentrations; however, because groundwater is thought to flow into Pahute Mesa from valleys north of Pahute Mesa, groundwater flow rates (i.e., underflow) and chloride concentrations from Kawich Valley and Gold Flat were carefully considered. Precipitation was measured with bulk and tipping-bucket precipitation gauges installed formore » this study at six sites on Pahute Mesa. These data, along with historical precipitation amounts from gauges on Pahute Mesa and estimates from the PRISM model, were evaluated to estimate mean annual precipitation. Chloride deposition from the atmosphere was estimated by analyzing quarterly samples of wet- and dry-deposition for chloride in the bulk gauges and evaluating chloride wet-deposition amounts measured at other locations by the National Atmospheric Deposition Program. Mean chloride concentrations in groundwater were estimated using data from the UGTA Geochemistry Database, data from other reports, and data from samples collected from emplacement boreholes for this study. Calculations were conducted assuming both no underflow and underflow from Kawich Valley and Gold Flat. Model results estimate recharge to be 30 mm/yr with a standard deviation of 18 mm/yr on Pahute Mesa, for elevations >1800 m amsl. These estimates assume Pahute Mesa recharge mixes completely with underflow from Kawich Valley and Gold Flat. The model assumes that precipitation, chloride concentration in bulk deposition, underflow and its chloride concentration, have been constant over the length of time of recharge.« less
Groundwater flow processes and mixing in active volcanic systems: the case of Guadalajara (Mexico)
NASA Astrophysics Data System (ADS)
Hernández-Antonio, A.; Mahlknecht, J.; Tamez-Meléndez, C.; Ramos-Leal, J.; Ramírez-Orozco, A.; Parra, R.; Ornelas-Soto, N.; Eastoe, C. J.
2015-02-01
Groundwater chemistry and isotopic data from 40 production wells in the Atemajac and Toluquilla Valleys, located in and around the Guadalajara metropolitan area, were determined to develop a conceptual model of groundwater flow processes and mixing. Multivariate analysis including cluster analysis and principal component analysis were used to elucidate distribution patterns of constituents and factors controlling groundwater chemistry. Based on this analysis, groundwater was classified into four groups: cold groundwater, hydrothermal water, polluted groundwater and mixed groundwater. Cold groundwater is characterized by low temperature, salinity, and Cl and Na concentrations and is predominantly of Na-HCO3 type. It originates as recharge at Primavera caldera and is found predominantly in wells in the upper Atemajac Valley. Hydrothermal water is characterized by high salinity, temperature, Cl, Na, HCO3, and the presence of minor elements such as Li, Mn and F. It is a mixed HCO3 type found in wells from Toluquilla Valley and represents regional flow circulation through basaltic and andesitic rocks. Polluted groundwater is characterized by elevated nitrate and sulfate concentrations and is usually derived from urban water cycling and subordinately from agricultural practices. Mixed groundwaters between cold and hydrothermal components are predominantly found in the lower Atemajac Valley. Tritium method elucidated that practically all of the sampled groundwater contains at least a small fraction of modern water. The multivariate mixing model M3 indicates that the proportion of hydrothermal fluids in sampled well water is between 13 (local groundwater) and 87% (hydrothermal water), and the proportion of polluted water in wells ranges from 0 to 63%. This study may help local water authorities to identify and quantify groundwater contamination and act accordingly.
Marra, Kristen R.; Elwood Madden, Megan E; Soreghan, Gerilyn S.; Hall, Brenda L
2014-01-01
BET surface area values are critical for quantifying the amount of potentially reactive sediments available for chemical weathering and ultimately, prediction of silicate weathering fluxes. BET surface area values of fine-grained (<62.5 μm) sediment from the hyporheic zone of polar glacial streams in the McMurdo Dry Valleys, Antarctica (Wright and Taylor Valleys) exhibit a wide range (2.5–70.6 m2/g) of surface area values. Samples from one (Delta Stream, Taylor Valley) of the four sampled stream transects exhibit high values (up to 70.6 m2/g), which greatly exceed surface area values from three temperate proglacial streams (0.3–12.1 m2/g). Only Clark stream in Wright Valley exhibits a robust trend with distance, wherein surface area systematically decreases (and particle size increases) in the mud fraction downstream, interpreted to reflect rapid dissolution processes in the weathering environment. The remaining transects exhibit a range in variability in surface area distributions along the length of the channel, likely related to variations in eolian input to exposed channel beds, adjacent snow drifts, and to glacier surfaces, where dust is trapped and subsequently liberated during summer melting. Additionally, variations in stream discharge rate, which mobilizes sediment in pulses and influences water:rock ratios, the origin and nature of the underlying drift material, and the contribution of organic acids may play significant roles in the production and mobilization of high-surface area sediment. This study highlights the presence of sediments with high surface area in cold-based glacier systems, which influences models of chemical denudation rates and the impact of glacial systems on the global carbon cycle.
NASA Astrophysics Data System (ADS)
Rodrigo Comino, J.; Brings, C.; Lassu, T.; Iserloh, T.; Senciales, J. M.; Martínez Murillo, J. F.; Ruiz Sinoga, J. D.; Seeger, M.; Ries, J. B.
2015-07-01
Vineyards are one of the eco-geomorphological systems most conditioned by human activity in Germany. The vineyards of the Ruwer Valley (Germany) are characterized by high soil erosion rates and rill problems on steep slopes (between 23 and 26°) caused by the increasingly frequent heavy rainfall events as well as deterioration due to incorrect land use managements. The objective of this paper is to determine and to quantify the hydrological and erosive phenomena in one vineyard in Germany during different seasons and under different management conditions (before, during and after vintage). For this purpose, a combined methodology was applied. Climatic (rainfall depth distributions and return periods), pedological (soil analysis and classification), geomorphological (sediment movements and rills evolution) and biological (botanic marks on the vines) variables were used on the two experimental plots in the village of Waldrach (Trier, region of Rhineland-Palatinate). The results showed high infiltration rates (near 100 %) and subsurface flow which were detected by rainfall simulations performed at different times of the year (between September and December). The highest variations of the monitored rills (lateral and frontal movements) were noted before and during vintage, when footsteps occurred concentrated during a short period of time (between September and October). Finally, two maps of soil loss were generated, indicated by botanic marks on the graft union of the vines. 62.5 t ha-1 yr-1 soil loss was registered in the experimental plots of the new vineyards (2 years), while 3.4 t ha-1 yr-1 was recorded in the old one (35 years).
NASA Astrophysics Data System (ADS)
Anders, Mark H.; Geissman, John Wm.; Piety, Lucille A.; Sullivan, J. Timothy
1989-02-01
The Intermountain and Idaho seismic belts within Idaho, Wyoming, and Montana form an unusual parabolic pattern about the axis of the aseismic eastern Snake River Plain (SRP). This pattern is also reflected in the distribution of latest Quaternary normal faults. Several late Cenozoic normal faults that trend perpendicular to the axis of the eastern SRP extend from the aseismic region to the region of latest Quaternary faulting and seismicity. A study of the late Miocene to Holocene displacement history of one of these, the Grand Valley fault system in southeastern Idaho and western Wyoming, indicates that a locus of high displacement rates has migrated away from the eastern SRP to its present location in southern Star Valley in western Wyoming. In Swan Valley the studied area closest to the eastern SRP, isotopic ages, and paleomagnetic data for over 300 samples from 47 sites on well-exposed late Cenozoic volcanic rocks (the tuff of Spring Creek, the tuff of Heise, the Huckleberry Ridge tuff, the Pine Creek Basalt, and an older tuff thought to be the tuff of Cosgrove Road) are used to demonstrate differences in the displacement rate on the Grand Valley fault over the last ˜10 m.y. Tectonic tilts for these volcanic rocks are estimated by comparing the results of paleomagnetic analyses in Swan Valley to similar analyses of samples from undeformed volcanic rocks outside of Swan Valley. Basin geometry and tilt axes are established using seismic reflection profiles and field mapping. Combining these data with the tilt data makes it possible to calculate displacement rates during discrete temporal intervals. An average displacement rate of ˜1.8 mm/yr is calculated for the Grand Valley fault in Swan Valley between 4.4 and 2.0 Ma. In the subsequent 2.0-m.y. interval the rate dropped 2 orders of magnitude to ˜0.014 mm/yr; during the preceding 5.5-m.y. interval the displacement rate is ˜0.15 mm/yr, or about 1 order of magnitude less than the rate between 4.4 and 2.0 Ma. Mapping of fault scarps and unfaulted deposits along the Grand Valley fault system shows that latest Quaternary fault scarps are restricted to the portion farthest from the eastern SRP, the southern part of the Star Valley fault. Surface displacements estimated from scarp profiles and deposit ages estimated from soil development suggest a latest Quaternary displacement rate of 0.6-1.2 mm/yr for the southern portion of the Star Valley fault. Morphologic evidence suggests that this displacement rate persisted on the Star Valley fault throughout most of the Quaternary. The latest Quaternary displacement rate calculated for the southern portion of the Star Valley fault is similar to the rate calculated for Swan Valley during the interval from 2.0 to 4.4 Ma. This similarity, together with evidence for a low Quaternary displacement rate on the fault system in Swan Valley, suggests that the location of the highest displacement rate has migrated away from the eastern SRP. Other normal faults in southeastern Idaho, northwestern Wyoming, and southwestern Montana, while less well described than the Grand Valley fault system, exhibit a similar outward migrating pattern of increased fault activity followed by quiescence. Furthermore, a temporal and spatial relationship between fault activity and the 3.5 cm/yr northeastward track of the Yellowstone hotspot is observable on the Grand Valley fault system and on other north-northwest trending late Cenozoic faults that border the eastern SRP. The temporal and spatial relationship of Miocene to present high displacement rates for other circumeastern SRP faults and the observable outwardly migrating pattern of fault activity suggest that a similar parabolic distribution of seismicity and high displacement rates was symmetrically positioned about the former position of the hotspot. Moreover, the tandem migration of the hotspot and the parabolic distribution of increased fault activity and seismicity are closely followed by a parabolic-shaped "collapse shadow," or region of fault inactivity and aseismicity. We suggest that the outwardly migrating pattern of increased fault activity (active region) results from reduced integrated lithospheric strength caused by thermal effects of the hotspot. Conversely, the outwardly propagating quiescent region is the result of a reduction or "collapse" of crustal extension rates caused by increased integrated lithospheric strength. Lithospheric strength in this region is increased by addition of mafic materials at the base of the crust and at midcrustal levels. Although the strength of the mantle portion of the lithosphere is reduced, the increased strength of the crust results in a total integrated increase in lithospheric strength. Paradoxically, the surface heat flow data suggest that the region within the interior parabola has a higher heat flow (after accounting for the cooling effects of the eastern SRP aquifer) than the adjacent regions, yet the interior region exhibits significantly lower extension rates. It appears that in this region the surface heat flow is not a good predictor of rates of lithospheric extension.
The State of the Union: Sexual Health Disparities in a National Sample of US College Students
ERIC Educational Resources Information Center
Buhi, Eric R.; Marhefka, Stephanie L.; Hoban, Mary T.
2010-01-01
Objective: To examine sexual health disparities between blacks and whites in a national sample of US college students. Participants and Method Summary: Analyses utilized secondary data from 44,165 nonmarried undergraduates (aged 18-24; M = 20.1) responding to the Spring 2007 American College Health Association-National College Health Assessment;…
The Economic Consequences of the Dissolution of Cohabiting Unions
ERIC Educational Resources Information Center
Avellar, Sarah; Smock, Pamela J.
2005-01-01
Although the economic effects of divorce have been well studied, a similar exploration of cohabitation has not been conducted. For this analysis, we use a sample from the National Longitudinal Survey of Youth (N=2,372) documenting changes in economic well-being at the end of a cohabiting relationship and comparing these results to a sample of…
Surviving the Vajont disaster: psychiatric consequences 36 years later.
Favaro, Angela; Zaetta, Cristina; Colombo, Giovanni; Santonastaso, Paolo
2004-03-01
The aim of the present study was to assess the chronic psychiatric consequences of the Vajont disaster in a group of survivors still living in the valley 36 years after the event. Thirty-nine subjects were assessed by means of a semistructured interview to investigate the extent of the traumatic experience and a structured diagnostic interview for the diagnoses of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD). The degree of traumatic exposure significantly predicts the presence of PTSD. The lifetime frequency of full PTSD was 26%, and a further 33% of the sample displayed partial PTSD. Lifetime MDD was present in 28% of the subjects, and its prediction factors were female gender and number of losses of first-degree relatives in the disaster. Trauma-related fears are very common in the sample. A large-scale disaster, such as that of the Vajont valley, affects the psychological health of survivors for decades.
Valley-Selective Exciton Bistability in a Suspended Monolayer Semiconductor.
Xie, Hongchao; Jiang, Shengwei; Shan, Jie; Mak, Kin Fai
2018-05-09
We demonstrate robust optical bistability, the phenomenon of two well-discriminated stable states depending upon the history of the optical input, in fully suspended monolayers of WSe 2 at low temperatures near the exciton resonance. Optical bistability has been achieved under continuous-wave optical excitation that is red-detuned from the exciton resonance at an intensity level of 10 3 W/cm 2 . The observed bistability is originated from a photothermal mechanism, which provides both optical nonlinearity and passive feedback, two essential elements for optical bistability. The low thermal conductance of suspended samples is primarily responsible for the low excitation intensities required for optical bistability. Under a finite out-of-plane magnetic field, the exciton bistability becomes helicity dependent due to the exciton valley Zeeman effect, which enables repeatable switching of the sample reflectance by light polarization. Our study has opened up exciting opportunities in controlling light with light, including its wavelength, power, and polarization, using monolayer semiconductors.
Rocket Research at Georgia Tech.
1981-11-01
samples were prepared by dry pressing 30% Valley Met H- 30 aluminum, 7% carnauba wax , and 63% 100 P AP. One sample was prepared using as received H-30, a...Al, and Carnauba wax powders. Sandwiches with aluminum in the binder lamina. Both pre-oxidation and pre-stretching treatments of aluminum particles...two different processes. 1. Dry-pressing powder mixtures in which polymeric binder is replaced by carnauba wax powder. 2. Hand mixing small samples of
Mubemba, B; Thompson, P N; Odendaal, L; Coetzee, P; Venter, E H
2017-05-01
Rift Valley fever (RVF), caused by an arthropod borne Phlebovirus in the family Bunyaviridae, is a haemorrhagic disease that affects ruminants and humans. Due to the zoonotic nature of the virus, a biosafety level 3 laboratory is required for isolation of the virus. Fresh and frozen samples are the preferred sample type for isolation and acquisition of sequence data. However, these samples are scarce in addition to posing a health risk to laboratory personnel. Archived formalin-fixed, paraffin-embedded (FFPE) tissue samples are safe and readily available, however FFPE derived RNA is in most cases degraded and cross-linked in peptide bonds and it is unknown whether the sample type would be suitable as reference material for retrospective phylogenetic studies. A RT-PCR assay targeting a 490 nt portion of the structural G N glycoprotein encoding gene of the RVFV M-segment was applied to total RNA extracted from archived RVFV positive FFPE samples. Several attempts to obtain target amplicons were unsuccessful. FFPE samples were then analysed using next generation sequencing (NGS), i.e. Truseq ® (Illumina) and sequenced on the Miseq ® genome analyser (Illumina). Using reference mapping, gapped virus sequence data of varying degrees of shallow depth was aligned to a reference sequence. However, the NGS did not yield long enough contigs that consistently covered the same genome regions in all samples to allow phylogenetic analysis. Copyright © 2017 Elsevier B.V. All rights reserved.
32 CFR Appendix A to Part 231 - Sample Operating Agreement
Code of Federal Regulations, 2010 CFR
2010-07-01
... financial institution the name, duty telephone number of the (Bank or Credit Union) Liaison Officer. h... and outdoor maintenance (such as grass cutting and snow removal) on a reimbursable basis. c. DoD...
32 CFR Appendix A to Part 231 - Sample Operating Agreement
Code of Federal Regulations, 2011 CFR
2011-07-01
... financial institution the name, duty telephone number of the (Bank or Credit Union) Liaison Officer. h... and outdoor maintenance (such as grass cutting and snow removal) on a reimbursable basis. c. DoD...
Lewis, Robert C.
1979-01-01
The Bowrnan-Gascoyne area is located in southwestern North Dakota. It is situated on the southwestern edge of the Williston structural basin and the northeastern flank of the Cedar Creek anticline. Strata of the Fort Union Formation (Paleocene), consisting of nonmarine claystone, sandstone, and lignite, dip to the northeast 25-50 ft/mi. Seven correlatable coal beds of varying thicknesses and areal dimensions occur in the area. The thickest and most persistent of these beds is the Harmon bed which attains a maximum thickness of 38 ft in T. 134 N., Rs. 101 and 102 W. Analyses show a heating value of 5,915-6,680 Btu/lb and a sulfur content of 0.6-1.4 percent. Two areas of high-coal-development potential are located near Gascoyne and Amidon. The Harmon bed in these two areas contains a total of 740,000,000 and 650,000,000 tons, respectively, and is under less than 150 ft of overburden.
Structure of the San Andreas fault zone at SAFOD from a seismic refraction survey
Hole, J.A.; Ryberg, T.; Fuis, G.S.; Bleibinhaus, F.; Sharma, A.K.
2006-01-01
Refraction traveltimes from a 46-km long seismic survey across the San Andreas Fault were inverted to obtain two-dimensional velocity structure of the upper crust near the SAFOD drilling project. The model contains strong vertical and lateral velocity variations from <2 km/s to ???6 km/s. The Salinian terrane west of the San Andreas Fault has much higher velocity than the Franciscan terrane east of the fault. Salinian basement deepens from 0.8 km subsurface at SAFOD to ???2.5 km subsurface 20 km to the southwest. A strong reflection and subtle velocity contrast suggest a steeply dipping fault separating the Franciscan terrane from the Great Valley Sequence. A low-velocity wedge of Cenozoic sedimentary rocks lies immediately southwest of the San Andreas Fault. This body is bounded by a steep fault just northeast of SAFOD and approaches the depth of the shallowest earthquakes. Multiple active and inactive fault strands complicate structure near SAFOD. Copyright 2006 by the American Geophysical Union.
NASA Technical Reports Server (NTRS)
Bar-Cohen, Y.; Sherrit, S.; Chang, Z.; Wessel, L.; Bao, X.; Doran, P. T.; Fritsen, C. H.; Kenig, F.; McKay, C. P.; Murray, A.;
2004-01-01
There is growing evidence for ice and fluids near the surface of Mars with potential discharge of brines, which may preserve a record of past life on the planet. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for such records.
Slowey, Aaron J.; Rytuba, James J.
2008-01-01
This report summarizes data obtained from field sampling of mine tailings and waste rock at the Rathburn and Petray Mines that was initiated in July 17, 2001 and water and sediment in regional springs and tributaries that drain from the mine area into Bear Creek on December 14, 2004 and February 16 and May 27, 2005. Although it was initially assumed that the mines were the cause of elevated levels of monomethyl Hg measured by the Central Regional Water Quality Control Board in tributaries near their confluence with Bear Creek (Foe and others, unpublished results), it became apparent during this study that ground water springs were also potential sources of Hg. In addition to sampling of springs in May 2005, saline ground water seepage along an unnamed fault on the west side of Bear Valley was sampled on December 13-14, 2006. We did not sample water or sediment in Bear Creek itself during this study. Our results permit a preliminary assessment of mining and natural sources of Hg and associated chemical constituents that could elevate levels of monomethyl Hg in Bear Creek.
NASA Astrophysics Data System (ADS)
Panday, A. K.; Prinn, R. G.; Regmi, R. P.
2006-12-01
The Kathmandu Valley is a bowl-shaped basin in the Nepal Himalaya, with a rapidly growing city surrounded by rice fields and steep terraced and forested mountain slopes. The valley's air quality is influenced by urban and rural emissions, nocturnal pooling of cold air, slope winds, and a daily exchange of air through mountain passes. To understand these processes and to inform air pollution policy in Nepal, we have carried out the most comprehensive study of air pollution in Nepal to date. During the 9-month dry season of 2004-2005, we carried out continuous measurements every minute of carbon monoxide, ozone, PM10, wind speed, wind direction, solar radiation, temperature, and humidity on the eastern edge of Kathmandu city, at a site that daily received air from both the city and rural areas. We recorded the diurnal cycle of the vertical temperature structure and stability with temperature loggers on towers and mountains. A sodar measured the mixed layer height and upper-level winds. 24-hour simultaneous bag sampling campaigns on mountain peaks, passes, the rural valley, and within the city provided glimpses of the spatial patterns of the diurnal cycle of CO -- a useful tracer of anthropogenic emissions. We measured winds on mountain passes and ozone on mountain peaks. At our main measurement site we found a daily-recurring pattern of CO and PM10, with an afternoon low showing rural background levels, even though the arriving air had traversed the city. This was followed by an evening peak starting at sunset, a second low late at night, and a morning peak enhanced by re-circulation. Pollutants emitted in the valley only traveled out of the valley between the late morning and sunset. During winter months, rush hour was outside of this period, enhancing the morning and evening peaks. Within the city, ozone dropped to zero at night. At mid-day we observed an ozone peak enhanced by photochemical production when the air mass that had been stagnant over the city swept past our site at the edge of the city. At nights on surrounding mountains, ozone remained high, while CO dropped to regional background levels. Using the MM5 model, we simulated the Kathmandu Valley's meteorology for selected days in February and May 2005. The model successfully captured essential features of the valley's meteorology. We used it to understand the origin and pathways of air arriving at our sites, and to address specific questions. At night polluted air was found to be lifted off the ground but not removed from the valley; it was mixed down again in the morning. The break-up of the valley's nocturnal temperature inversion was dominated in February by up- slope flows along the valley rim mountains, plus subsidence over the fog-covered valley center. In May, when there was no fog, surface heating of the valley floor also contributed. During the mornings some pollutants were ventilated out of the valley by upslope flows. From late mornings through afternoons, strong westerly winds arriving through the valley's western passes brought rural background air into the city, while rapidly sweeping the night and morning's emissions out the eastern passes. Pollutants emitted into the afternoon westerly winds left the valley in less than 2 hours; pollutants emitted after the winds ceased at sunset lingered for up to 18 hours. The timing of emissions therefore has a bigger effect on air quality within the valley than the daily total emissions; this is important for policy considerations. More details can be found at http://web.mit.edu/cgcs/www/MIT_CGCS_Rpt75.html.
NASA Astrophysics Data System (ADS)
Ferreira, B. C.; Valverde, M. C.
2013-05-01
The aim of this paper is to analyze the occurrence of floods facing the rate of urbanization in the Ribeira Valley. The Ribeira Valley is located on the basin of Ribeira de Iguape River in eastern Paraná and southeastern São Paulo state in Brazil. The region has been considered one of the most important international conservation priorities by agencies such as the International Union for the Conservation of Nature (IUCN), and the UNESCO/MAB Program. This region has a history of recurrent floods, causing huge financial losses particularly to the poorest people, including casualties as well as material losses. This study analyzed three flood events that occurred in January 1995, January 1997 and February-March 1998, reaching the towns of Eldorado, Ribeira and Sete Barras. To determine the affected areas, the researchers used the shapes (digital data) obtained from the Geographic Information System of Ribeira de Iguape River Basin which is maintained by the Ribeira de Iguape River Basin and South Seashore Committee. The SPRING was the processing tool used for data manipulation. Additionally we used rainfall data, flow and water level elevation for the years 1983, 1995, 1997, 1998 and 2011. The results show that in January 1997 there happened the largest flood area across the three cities and this effect coincides with the highest levels of rainfall and flow. The second largest flood happened in January 1995 and the smallest one was in February-March 1998. Another important aspect to be noted is that all floods affected a large floodplain in both rural and urban areas. It was also found a direct relationship between the rate of urbanization and the area affected by the floods. The results show that the larger the area of urbanization, the larger the flooded area. It was also verified in the precipitation climatology that most extreme events occurred in 1983 and 2011. Specifically the 2011 event occurred during dry season bringing the whole region to a state of emergency, reaching 17 municipalities. The Ribeira Valley reached its flood peak of 13.45 m on 08/02/2011 in Eldorado with a total of 27,931 people affected. Since the urban areas for the cities studied are vulnerable to flood risk, it is necessary a thorough registration of the worst event reaching the whole area and the people affected in order to find the best way to mitigate the impacts of this natural disaster.
Multi-scale curvature for automated identification of glaciated mountain landscapes
NASA Astrophysics Data System (ADS)
Prasicek, Günther; Otto, Jan-Christoph; Montgomery, David R.; Schrott, Lothar
2014-03-01
Erosion by glacial and fluvial processes shapes mountain landscapes in a long-recognized and characteristic way. Upland valleys incised by fluvial processes typically have a V-shaped cross-section with uniform and moderately steep slopes, whereas glacial valleys tend to have a U-shaped profile with a changing slope gradient. We present a novel regional approach to automatically differentiate between fluvial and glacial mountain landscapes based on the relation of multi-scale curvature and drainage area. Sample catchments are delineated and multiple moving window sizes are used to calculate per-cell curvature over a variety of scales ranging from the vicinity of the flow path at the valley bottom to catchment sections fully including valley sides. Single-scale curvature can take similar values for glaciated and non-glaciated catchments but a comparison of multi-scale curvature leads to different results according to the typical cross-sectional shapes. To adapt these differences for automated classification of mountain landscapes into areas with V- and U-shaped valleys, curvature values are correlated with drainage area and a new and simple morphometric parameter, the Difference of Minimum Curvature (DMC), is developed. At three study sites in the western United States the DMC thresholds determined from catchment analysis are used to automatically identify 5 × 5 km quadrats of glaciated and non-glaciated landscapes and the distinctions are validated by field-based geological and geomorphological maps. Our results demonstrate that DMC is a good predictor of glacial imprint, allowing automated delineation of glacially and fluvially incised mountain landscapes.
Boissin, Emilie; Hoareau, Thierry B; Paulay, Gustav; Bruggemann, J Henrich
2016-04-06
Despite their importance in marine biodiversity, invertebrates are far less studied than vertebrates. Given the current global biodiversity crisis and insufficient taxonomic resources, sustained efforts need to be undertaken to assess species diversity, especially in the highly threatened 'biodiversity hotspots'. Réunion is a young volcanic island lying in the Mascarene Islands (south-western Indian Ocean, SWIO), a marine biodiversity hotspot. A substantial sampling effort was conducted around Réunion Island to document shallow water reef-associated ophiuroid (brittle-stars) diversity, a class recognised as the most diverse among echinoderms. A total of 33 species were documented, increasing the known species richness of the island by 56%. Findings include 15 new records for Réunion, 11 for the Mascarene Islands and 8 for the Indian Ocean. The most diverse family was Ophiocomidae, a family of large, abundant and conspicuous tropical species. Even in this well studied family, a new species was revealed by this survey. Morphological variants together with DNA sequence variations within several species revealed cryptic species. We compared our results with the known fauna of other Mascarene Islands and discuss biogeographic implications for the region.
Justus, B.G.; Meredith, Bradley J.
2014-01-01
This report describes a study to identify reference lakes in two lake classifications common to parts of two level III ecoregions in western Arkansas—the Arkansas Valley and Ouachita Mountains. Fifty-two lakes were considered. A screening process that relied on land-use data was followed by reconnaissance water-quality sampling, and two lakes from each ecoregion were selected for intensive water-quality sampling. Our data suggest that Spring Lake is a suitable reference lake for the Arkansas Valley and that Hot Springs Lake is a suitable reference lake for the Ouachita Mountains. Concentrations for five nutrient constituents—orthophosphorus, total phosphorus, total kjeldahl nitrogen, total nitrogen, and total organic carbon—were lower at Spring Lake on all nine sampling occasions and transparency measurements at Spring Lake were significantly deeper than measurements at Cove Lake. For the Ouachita Mountains ecoregion, water quality at Hot Springs Lake slightly exceeded that of Lake Winona. The most apparent water-quality differences for the two lakes were related to transparency and total organic carbon concentrations, which were deeper and lower at Hot Springs Lake, respectively. Our results indicate that when nutrient concentrations are low, transparency may be more valuable for differentiating between lake water quality than chemical constituents that have been useful for distinguishing between water-quality conditions in mesotrophic and eutrophic settings. For example, in this oligotrophic setting, concentrations for chlorophyll a can be less than 5 μg/L and diurnal variability that is typically associated with dissolved oxygen in more productive settings was not evident.
Health-related quality of life in a binational population with diabetes at the Texas-Mexico border.
Mier, Nelda; Bocanegra-Alonso, Anabel; Zhan, Dongling; Zuniga, Miguel A; Acosta, Rosa I
2008-03-01
To examine physical and mental health domains of health-related quality of life (HRQL) in a binational adult population with type 2 diabetes at the Texas-Mexico border, and to explore individual and social correlates to physical and mental health status. Adults 18 years and older with type 2 diabetes residing in the South Texas Lower Rio Grande Valley and in Reynosa, Tamaulipas, Mexico, were recruited using a convenience sampling technique and interviewed face-to-face with a structured survey. HRQL was measured using physical and mental health summary components of the Medical Outcomes Study Short Form. HRQL correlates included demographic characteristics, health factors, access to healthcare, and family support. Samples characteristics were compared using the Student's t-test or Mann-Whitney U test. Associations between dependent and independent variables were examined using unadjusted and adjusted (multiple variable) logistic regression models. There were no significant differences between Valley and Reynosa respondents in physical or mental health status scores. Valley participants with lower socioeconomic status and those perceiving their supportive relative's level of diabetes-related knowledge as "low" were more likely to report worse physical health than those lacking those characteristics. In the Reynosa group, lower physical health status was associated with duration of diabetes and insulin use. Both sample populations with clinical depressive symptoms were more likely to have worse physical and mental health than those without such symptoms. HRQL is an important outcome in monitoring health status. Understanding the levels and influences of HRQL in U.S.-Mexico border residents with diabetes may help improve diabetes management programs.
Durkee, Jenna; Bartrem, Casey; Möller, Gregory
2017-02-01
From the early 1900s to the 1950s, Yakima Valley orchards were commonly treated with lead arsenate (LA) insecticides. Lead (Pb) and arsenic (As) soil contamination has been identified on former orchard lands throughout Central Washington and pose a threat to human health and the environment. The levels of Pb and As in soil and interior dust at participating childcare centers in the Upper Yakima Valley (Yakima County), Washington were sampled to explore exposure potential for young children. Childcare center soils were collected from two soil depths, homogenized, and analyzed in bulk by a field-portable X-ray fluorescence spectrometer (XRF). Interior dust wipes samples were collected from at least two locations in each facility. All soil samples >250 mg/kg Pb and/or >20 As mg/kg were sieved to 250 μm, tested by XRF a second time, and analyzed via acid digestion and inductively coupled plasma mass spectrometry (ICP-MS) analysis. Bulk and sieved XRF results, as well as ICP-MS to XRF results were strongly correlated. Maximum Pb and As XRF results indicated that 4 (21%) and 8 (42%) of the 19 childcare centers surveyed exceeded the regulatory standard for Pb and As, respectively. Historic land use was significantly associated with elevated Pb and As levels. Interior dust loadings were below United States Environmental Protection Agency (EPA) guidelines. Childcare centers are areas of intensive use for children and when coupled with potential residential exposure in their homes, the total daily exposure is a potential hazard to children. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fonseca-Salazar, María Alejandra; Díaz-Ávalos, Carlos; Castañón-Martínez, María Teresa; Tapia-Palacios, Marco Antonio; Mazari-Hiriart, Marisa
2016-12-01
In Latin America and the Caribbean, with a population of approximately 580 million inhabitants, less than 20 % of wastewater is treated. Megacities in this region face common challenges and problems related with water quality and sanitation, which require urgent actions, such as changes in the sustainable use of water resources. The Mexico City Metropolitan Area is one of the most populous urban agglomerations in the world, with over 20 million inhabitants, and is no exception to the challenges of sustainable water management. For more than 100 years, wastewater from Mexico City has been transported north to the Mezquital Valley, which is ranked as the largest wastewater-irrigated area in the world. In this study, bacteria and pathogenic protozoa were analyzed to determine the association between the presence of such microorganisms and water types (WTs) across sampling sites and seasons in Mexico City and the Mezquital Valley. Our results show a difference in microbiological water quality between sampling sites and WTs. There is no significant interaction between sampling sites and seasons in terms of bacterial concentration, demonstrating that water quality remains constant at each site regardless of whether it is the dry or the rainy season. The results illustrate the quantity of these microorganisms in wastewater, provide a current diagnosis of water quality across the area which could affect the health of residents in both Mexico City and the Mezquital Valley, and demonstrate the need to transition in the short term to treat wastewater from a local to a regional scale.
Frankel, K.L.; Brantley, K.S.; Dolan, J.F.; Finkel, R.C.; Klinger, R.E.; Knott, J.R.; Machette, M.N.; Owen, L.A.; Phillips, F.M.; Slate, J.L.; Wernicke, B.P.
2007-01-01
The northern Death Valley fault zone (NDVFZ) has long been recognized as a major right-lateral strike-slip fault in the eastern California shear zone (ECSZ). However, its geologic slip rate has been difficult to determine. Using high-resolution digital topographic imagery and terrestrial cosmogenic nuclide dating, we present the first geochronologically determined slip rate for the NDVFZ. Our study focuses on the Red Wall Canyon alluvial fan, which exposes clean dextral offsets of seven channels. Analysis of airborne laser swath mapping data indicates ???297 ?? 9 m of right-lateral displacement on the fault system since the late Pleistocene. In situ terrestrial cosmogenic 10Be and 36C1 geochronology was used to date the Red Wall Canyon fan and a second, correlative fan also cut by the fault. Beryllium 10 dates from large cobbles and boulders provide a maximum age of 70 +22/-20 ka for the offset landforms. The minimum age of the alluvial fan deposits based on 36Cl depth profiles is 63 ?? 8 ka. Combining the offset measurement with the cosmogenic 10Be date yields a geologic fault slip rate of 4.2 +1.9/-1.1 mm yr-1, whereas the 36Cl data indicate 4.7 +0.9/-0.6 mm yr-1 of slip. Summing these slip rates with known rates on the Owens Valley, Hunter Mountain, and Stateline faults at similar latitudes suggests a total geologic slip rate across the northern ECSZ of ???8.5 to 10 mm yr-1. This rate is commensurate with the overall geodetic rate and implies that the apparent discrepancy between geologic and geodetic data observed in the Mojave section of the ECSZ does not extend north of the Garlock fault. Although the overall geodetic rates are similar, the best estimates based on geology predict higher strain rates in the eastern part of the ECSZ than to the west, whereas the observed geodetic strain is relatively constant. Copyright 2007 by the American Geophysical Union.
NASA Astrophysics Data System (ADS)
Falcucci, Emanuela; Gori, Stefano; Della Seta, Marta; Fubelli, Giandomenico; Fredi, Paola
2014-05-01
The Middle Aterno River Valley is characterised by different Quaternary tectonic depressions localised along the present course of the Aterno River (Central Apennine) .This valley includes the L'Aquila and Paganica-Castelnuovo-San Demetrio tectonic basins, to the North, the Middle Aterno Valley and the Subequana tectonic basin, to the South. The aim of this contribution is to improve the knowledge about the Quaternary geomorphological and tectonic evolution of this portion of the Apennine chain. A synchronous lacustrine depositional phase is recognized in all these basins and attributed to the Early Pleistocene by Falcucci et al. (2012). At that time, this sector of the chain showed four distinct closed basins, hydrologically separated from each other and from the Sulmona depression. This depression, actually a tectonic basin too, was localized South of the Middle Aterno River Valley and it was drained by an endorheic hydrographic network. The formation of these basins was due to the activity of different fault systems, namely the Upper Aterno River Valley-Paganica system and San Pio delle Camere fault, to the North, and the Middle Aterno River Valley-Subequana Valley fault system to the South. These tectonic structures were responsible for the origin of local depocentres inside the depressions which hosted the lacustrine basins. Ongoing surveys in the uppermost sectors of the Middle Aterno River Valley revealed the presence of sub-horizontal erosional surfaces that are carved onto the carbonate bedrock and suspended several hundreds of metres over the present thalweg. Gently dipping slope breccias referred to the Early Pleistocene rest on these surfaces, thus suggesting the presence of an ancient low-gradient landscape adjusting to the local base level.. Subsequently, this ancient low relief landscape underwent a strong erosional phase during the Middle Pleistocene. This erosional phase is testified by the occurrence of valley entrenchment and of coeval fluvial deposition within the Middle Aterno River Valley. These fluvial deposits are deeply embedded into the lacustrine sequence, thus suggesting the happening of a hydrographic connection among the originally separated tectonic depressions. This was probably due to the headward erosion by streams draining the Sulmona depression that progressively captured the hydrological networks of the Subequana basin, the Middle Aterno Valley, the L'Aquila and Paganica-Castelnuovo-San Demetrio basins to the North. Stream piracy was probably helped by an increase of the regional uplift rate, occurred between the Lower and the Middle Pleistocene. To reconstruct the paleo-landscape that characterised the early stages of these basins formation we sampled the remnants of the Quaternary erosinal/depositional surfaces and reconstructed the ancient topographic surfaces using the Topo to Raster tool of ArcGIS 10.0 package. Finally we have cross-checked the geological and geomorphological data with the model of the Middle Aterno River paleo-drainage basin obtained through the GIS based method. References Falcucci E., Scardia G., Nomade S., Gori S., Giaccio B., Guillou H., Fredi P. (2012). Geomorphological and Quaternary tectonic evolution of the Subequana basin and the Middle Aterno Valley (central Apennines).16th Joint Geomorphological Meeting Morphoevolution of Tectonically Active Belts Rome, July 1-5, 2012
NASA Astrophysics Data System (ADS)
Yoskowitz, Joshua; Clark, Morgan; Labrake, Scott; Vineyard, Michael
2015-10-01
We have developed an external beam facility for the 1.1-MV tandem Pelletron accelerator in the Union College Ion Beam Analysis Laboratory. The beam is extracted from an aluminum pipe through a 1 / 4 ' ' diameter window with a 7.5- μm thick Kapton foil. This external beam facility allows us to perform ion beam analysis on samples that cannot be put under vacuum, including wet samples and samples too large to fit into the scattering chamber. We have commissioned the new facility by performing proton induced X-ray emission (PIXE) analysis of several samples of environmental interest. These include samples of artificial turf, running tracks, and a human tooth with an amalgam filling. A 1.7-MeV external proton beam was incident on the samples positioned 2 cm from the window. The resulting X-rays were measured using a silicon drift detector and were analyzed using GUPIX software to determine the concentrations of elements in the samples. The results on the human tooth indicate that while significant concentrations of Hg, Ag, and Sn are present in the amalgam filling, only trace amounts of Hg appear to have leached into the tooth. The artificial turf and running tracks show rather large concentrations of a broad range of elements and trace amounts of Pb in the turf infill.
ANALYSIS OF GEOTHERMAL WASTES FOR HAZARDOUS COMPONENTS
Regulations governing the disposal of hazardous wastes led to an assessment for geothermal solid wastes for potentially hazardous properties. Samples were collected from three active geothermal sites in the western United States: The Geysers, Imperial Valley, and northwestern Nev...
NASA Astrophysics Data System (ADS)
Margold, Martin; Froese, Duane G.; Gosse, John C.; Yang, Guang; McKenna, Jillian; Hidy, Alan J.
2017-04-01
The detachment of the Laurentide Ice Sheet margin from the Canadian Cordillera opened the present-day drainage route of the Mackenzie River to the Arctic Ocean and an ice-free corridor that allowed for migration of species between Beringia and the mid-latitudes of North America. The existing ice-margin chronology depicts the southern reach of the Mackenzie River between 61 and 63° N as glaciated until about 13 ka, representing the last portion of the Laurentide Ice Sheet margin abutting the eastern foot of the Cordillera. A substantial retreat of the ice sheet margin in this region has been suggested to have occurred during the subsequent Younger Dryas cold period, despite the fact that in many other regions ice masses stabilised or even re-grew at this time. However, until now, deglacial chronometry for this region and the western LIS margin is sparse and consists mostly of minimum-limiting macrofossil and bulk C-14 ages from organics materials overlying glacial sediment. With the aim to bring new data on the deglaciation history of the Mackenzie River valley, we collected samples for Be-10 exposure dating from glacial erratic boulders in the southern Franklin Mountains that bound the Mackenzie River valley from the east. The sampling elevations ranged between 1480 and 800 m a.s.l., however, the measured ages show only a weak correlation with elevation. Instead, 10 out of 12 measured samples cluster tightly around 15 ka, with the remaining two samples likely containing Be-10 inherited from previous periods of exposure. Our results thus indicate a pre-Younger Dryas rapid down-wasting of the ice sheet surface, which we infer was accompanied by an ice margin retreat to the southeast. The southern reach of the Mackenzie River valley at the eastern foot of the Cordillera was, according to our results, ice free shortly after 15 ka, with the prospect that the ice-free corridor might have opened significantly earlier than hitherto anticipated. Further research is required in the region south of our study area to establish a firm chronological control on the separation of the Cordilleran and Laurentide ice sheets and the opening of the ice free corridor.
Naranjo, Ramon C.; Welborn, Toby L.; Rosen, Michael R.
2013-01-01
The distribution of nitrate as nitrogen (referred to herein as nitrate-N) concentrations in groundwater was determined by collecting more than 200 samples from 8 land-use categories: single family residential, multifamily residential, rural (including land use for agriculture), vacant land, commercial, industrial, utilities, and unclassified. Nitrate-N concentrations ranged from below detection (less than 0.05 milligrams per liter) to 18 milligrams per liter. The results of nitrate-N concentrations that were sampled from three wells equalled or exceeded the maximum contaminant level of 10 milligrams per liter set by the U.S. Environmental Protection Agency. Nitrate-N concentrations in sampled wells showed a positive correlation between elevated nitrate-N concentrations and the percentage of single-family land use and septic-system density. Wells sampled in other land-use categories did not have any correlation to nitrate-N concentrations. In areas with greater than 50-percent single-family land use, nitrate-N concentrations were two times greater than in areas with less than 50 percent single-family land use. Nitrate-N concentrations in groundwater near septic systems that had been used more than 20 years were more than two times greater than in areas where septic systems had been used less than 20 years. Lower nitrate-N concentrations in the areas where septic systems were less than 20 years old probably result from temporary storage of nitrogen leaching from septic systems into the unsaturated zone. In areas where septic systems are abundant, nitrate-N concentrations were predicted to 2059 by using numerical models within the Ruhenstroth and Johnson Lane subdivisions in the Carson Valley. Model results indicated that nitrate-N concentrations will continue to increase and could exceed the maximum contaminant level over extended areas inside and outside the subdivisions. Two modeling scenarios were used to simulate future transport as a result of removal of septic systems (source of nitrate-N contamination) and the termination of domestic pumping of groundwater. The models showed the largest decrease in nitrate-N concentrations when septic systems were removed and wells continued to pump. Nitrate-N concentrations probably will continue to increase in areas that are dependent on septic systems for waste disposal either under current land-use conditions in the valley or with continued growth and change in land use in the valley.
Agglutinates as recorders of fossil soil compositions. [of Apollo 17 lunar probes
NASA Technical Reports Server (NTRS)
Taylor, G. J.; Wentworth, S.; Warner, R. D.; Keil, K.
1978-01-01
The composition of agglutinates in polished sections of the Apollo 17 drill core was studied in an attempt to deduce the nature of the Taurus-Littrow valley regolith prior to the formation of the Camelot and Central Cluster craters. The agglutinate compositions in the soils differed from the host soil compositions except for samples from the North Massif. Local materials from the valley floor and the massifs appear to form the pre-Central Cluster regolith. It is also shown that chemical mixing models for bulk soil compositions can be misleading unless the petrologic characteristics of each soil are taken into account.
A water-quality monitoring network for Vallecitos Valley, Alameda County, California
Farrar, C.D.
1980-01-01
A water-quality monitoring network is proposed to detect the presence of and trace the movement of radioisotopes in the hydrologic system in the vicinity of the Vallecitos Nuclear Center. The source of the radioisotopes is treated industrial wastewater from the Vallecitos Nuclear Center that is discharged into an unnamed tributary of Vallecitos Creek. The effluent infiltrates the alluvium along the stream course, percolates downward to the water table, and mixes with the native ground water in the subsurface. The average daily discharge of effluent to the hydrologic system in 1978 was about 100,000 gallons. In Vallecitos Valley, the Livermore Gravel and the overlying alluvium constitute the ground-water reservoir. There is no subsurface inflow from adjacent ground-water basins. Ground-water flow in the Vallecitos subbasin is toward the southwest.The proposed network consists of four surface-water sampling sites and six wells to sample the ground-water system. Samples collected monthly at each site and analyzed for tritium and for alpha, beta, and gamma radiation would provide adequate data for monitoring.
NASA Astrophysics Data System (ADS)
Gillies, S. L.; Marsh, S. J.; Peucker-Ehrenbrink, B.; Janmaat, A.; Bourdages, M.; Paulson, D.; Bogaerts, P.; Robertson, K.; Clemence, E.; Smith, S.; Yakemchuk, A.; Faber, A.
2017-12-01
Faculty and students from the University of the Fraser Valley (UFV) have conducted time series sampling of the Fraser River at Fort Langley and six Fraser Valley tributaries as a member of the Global Rivers Observatory (GRO, www.globalrivers.org) coordinated by Woods Hole Oceanographic Institution and Woods Hole Research Center. The Clayburn - Willband - Stoney watershed has become a focus of the sampling being conducted by faculty and students from the Geography and Biology Departments at UFV. Water chemistry data (water temperature, dissolved oxygen, conductivity, pH and turbidity) and samples (nutrients, major ions and bacteria) have been collected weekly from sites on these creeks. These watersheds are threatened by increasing urban development, increasing idustrial activity, and expansion of agricultural landuse within the watershed. Documenting the seasonal changes in the water chemistry as measured during the onset of the heavy fall and winter precipitation events, the wet and cool winters and springs, and the hot and dry summers will assist in attempts to protect these important salmon spawning streams from anthropogenic activity.
Hadean silicate differentiation revealed by anomalous 142Nd in the Réunion hotspot source
NASA Astrophysics Data System (ADS)
Peters, B. J.; Carlson, R.; Day, J. M.; Horan, M.
2017-12-01
Geochemical and geophysical data show that volcanic hotspots can tap ancient domains sequestered in Earth's deep mantle. Evidence from stable and long-lived radiogenic isotope systems has demonstrated that many of these domains result from tectonic and differentiation processes that occurred more than two billion years ago. Recent advances in the analysis of short-lived radiogenic isotopes have further shown that some hotspot sources preserve evidence for metal-silicate differentiation occurring within the first one percent of Earth's history. Despite these discoveries, efforts to detect variability in the lithophile 146Sm-142Nd (t1/2 = 103 Ma) system in Phanerozoic hotspot lavas have not yet detected significant global variation. We report 142Nd/144Nd ratios in Réunion Island basalts that are statistically distinct from the terrestrial Nd standard ranging to both higher and lower 142Nd/144Nd. Variations in 142Nd/144Nd, which total nearly 15 ppm on Réunion, are correlated with 3He/4He among both anomalous and non-anomalous samples. Such behavior implies that there were analogous changes in Sm/Nd and (U+Th)/3He that occurred during a Hadean silicate differentiation event and were not completely overprinted by the depleted mantle. Variations in the 142Nd-143Nd compositions of Réunion basalts can be explained by a single Hadean melting event producing enriched and depleted domains that partially re-mixed after 146Sm was no longer extant. Assuming differentiation occurred at pressures where perovskite is stable, anomalies of the magnitude observed in Réunion basalts require melting of at least 50% across a wide depth range, and up to 90% for melting at pressures near those of the deepest mantle. Models with best fits to Nd isotope data suggest this differentiation occurred around 4.40 Ga and mixing occurred after 4 Ga. This two-stage differentiation process nearly erased the ancient, anomalous 142Nd composition of the Réunion source and produced the relatively invariant 143Nd signature that is a hallmark of Réunion hotspot lavas. Given growing evidence that the Réunion hotspot source represents an unusually ancient, primitive mantle domain, these new data argue that Réunion is a critical source of information regarding the formation and preservation of ancient heterogeneities in Earth's deep interior.
Manning, Andrew H.; Mills, Christopher T.; Morrison, Jean M.; Ball, Lyndsay B.
2015-01-01
Environmental tracers are useful for determining groundwater age and recharge source, yet their application in studies of geogenic Cr(VI) in groundwater has been limited. Environmental tracer data from 166 wells located in the Sacramento Valley, northern California, were interpreted and compared to Cr concentrations to determine the origin and age of groundwater with elevated Cr(VI), and better understand where Cr(VI) becomes mobilized and how it evolves along flowpaths. In addition to major ion and trace element concentrations, the dataset includes δ18O, δ2H, 3H concentration, 14C activity (of dissolved inorganic C), δ13C, 3He/4He ratio, and noble gas concentrations (He, Ne, Ar, Kr, Xe). Noble gas recharge temperatures (NGTs) were computed, and age-related tracers were interpreted in combination to constrain the age distribution in samples and sort them into six different age categories spanning from <60 yr old to >10,000 yr old. Nearly all measured Cr is in the form of Cr(IV). Concentrations range from <1 to 46 μg L−1, with 10% exceeding the state of California’s Cr(VI) maximum contaminant level of 10 μg L−1. Two groups with elevated Cr(VI) (⩾5 μg L−1) were identified. Group 1 samples are from the southern part of the valley and contain modern (<60 yr old) water, have elevated NO3− concentrations (>3 mg L−1), and commonly have δ18O values enriched relative to local precipitation. These samples likely contain irrigation water and are elevated due to accelerated mobilization of Cr(VI) in the unsaturated zone (UZ) in irrigated areas. Group 2 samples are from throughout the valley and typically contain water 1000–10,000 yr old, have δ18O values consistent with local precipitation, and have unexpectedly warm NGTs. Chromium(VI) concentrations in Group 2 samples may be elevated for multiple reasons, but the hypothesis most consistent with all available data (notably, the warm NGTs) is a relatively long UZ residence time due to recharge through a deep UZ near the margin of the basin. A possible explanation for why Cr(VI) may be primarily mobilized in the UZ rather than farther along flowpaths in the oxic portion of the saturated zone is more dynamic cycling of Mn in the UZ due to transient moisture and redox conditions.
Symbolic Uses of the Berlin Wall, 1961-1989.
ERIC Educational Resources Information Center
Bruner, Michael S.
1989-01-01
Examines samples from public discourse during the period 1961-1989, which reveal several different symbolic uses of the Berlin Wall. Suggests these differences reflect the never-completed struggle between the United States and the Soviet Union. (KEH)
Ahmad, Bashir; Rehman, Atta Ur; Malik, Sajid
2016-01-01
The north-western populations of Pakistan in the Federally Administered Tribal Areas (FATA) adjoining the Pakistan-Afghanistan border are an amalgamation of native and migrated Pashtun tribes. These tribal populations are in transition due to war conditions and geo-political turmoil on both sides of the border since the Soviet invasion in 1979. Bio-demographic and epidemiological data for these tribes are scarce. A prospective cross-sectional sample of 967 males was selected from a representative Pashtun population of Bajaur Agency, and information obtained on bio-demographic variables and marital union types. Analysis of these data revealed that consanguinity was 22.34% and the inbreeding coefficient F was calculated to be 0.0134. The inbreeding coefficient was observed to be higher in subjects who were illiterate, had unskilled jobs and who belonged to younger age categories, extended families and the Tarkalani tribe. Further analyses with respect to temporal variables like subject's age, year of marriage and age at marriage revealed that after a transition in marital union types in the early 80s, there has been a declining trend in the rate of consanguineous unions. Further, consanguineous unions in the parental generation were only 5%, but parental marriage types were predictors of subjects' marital union types. The data further establish that, contrary to a general notion about a high consanguinity rate in Pakistan, consanguineous unions are not common in Bajaur Agency and first cousin marriage is not the preferred type. Furthermore, this research shows that there is a great regional variation in the pattern of consanguinity in Pakistan that needs to be documented in order to draw a more comprehensive picture of the inbreeding coefficient in the country.
Thiros, Susan A.
2003-01-01
Residential and commercial development of about 80 square miles that primarily replaced undeveloped and agricultural areas occurred in Salt Lake Valley, Utah, from 1963 to 1994. This study evaluates the occurrence and distribution of natural and anthropogenic compounds in shallow ground water underlying recently developed (post 1963) residential and commercial areas. Monitoring wells from 23 to 153 feet deep were installed at 30 sites. Water-quality data for the monitoring wells consist of analyses of field parameters, major ions, trace elements, nutrients, dissolved organic carbon, pesticides, and volatile organic compounds.Dissolved-solids concentration ranged from 134 to 2,910 milligrams per liter (mg/L) in water from the 30 monitoring wells. Dissolved arsenic concentration in water from 12 wells exceeded the drinking-water maximum contaminant level of 10 micrograms per liter. Water from monitoring wells in the northwestern part of the valley generally contained higher arsenic concentrations than did water from other areas. Nitrate concentration in water sampled from 26 of the 30 monitoring wells (86.7 percent) was higher than a background level of 2 mg/L, indicating a possible human influence. Nitrate concentrations ranged from less than 0.05 to 13.3 mg/L.Fifteen of the 104 pesticides and pesticide degradation products analyzed for were detected in 1 or more water samples from the monitoring wells. No pesticides were detected at concentrations that exceeded U.S. Environmental Protection Agency drinking-water standards or guidelines for 2002. The high detection frequency of atrazine, a restricted-use pesticide, in residential areas on the west side of Salt Lake Valley may be the result of application in agricultural or industrial areas that have been converted to residential uses or application in areas upgradient from the residential areas that was then transported by ground water.Fifteen of the 86 volatile organic compounds analyzed for were detected in 1 or more water samples from the monitoring wells. The most frequently detected volatile organic compounds were chloroform (90 percent), bromodichloromethane (56.7 percent), tetrachloroethylene (53.3 percent), and 1,1,1-trichloroethane (50 percent). The widespread occurrence of chloroform and bromodichloromethane in shallow ground water is likely a result of the recharge of chlorinated public-supply water used to irrigate lawns and gardens in residential areas of Salt Lake Valley. Tetrachloroethylene (PCE), primarily used as a dry cleaning agent and solvent, was detected in water from 16 wells.
Graczyk, David J.; Walker, John F.; Bannerman, Roger T.; Rutter, Troy D.
2012-01-01
In many watersheds, nonpoint-source contamination is a major contributor to water-quality problems. In response to the recognition of the importance of nonpoint sources, the Wisconsin Nonpoint Source Water Pollution Abatement Program (Nonpoint Program) was enacted in 1978. This report summarizes the results of a study to assess the effectiveness of watershed-management practices for controlling nonpoint-source contamination for the Eagle Creek and Joos Valley Creek Watersheds. Streamflow-gaging stations equipped for automated sample collection and continuous recording of stream stage were installed in July 1990 at Eagle and Joos Valley Creeks and were operated through September 2007. In October 1990, three rain gages were installed in each watershed and were operated through September 2007. Best-Management Practices (BMPs) were installed during 1993 to 2000 in Eagle and Joos Valley Creeks and were tracked throughout the study period. By the year 2000, a majority of the BMPs were implemented in the two watersheds and goals set by the Wisconsin Department of Natural Resources and the local Land Conservation Department had been achieved for the two study watersheds (Wisconsin Department of Natural Resources, 1990). The distributions of the rainstorms that produced surface runoff and storm loads were similar in the pre-BMP (1990-93) and post-BMP implementation (2000-07) periods for both Eagle and Joos Valley Creeks. The highest annual streamflow occurred at both sites in water year 1993, which corresponded to the greatest above normal nonfrozen precipitation measured at two nearby NOAA weather stations. The minimum streamflow occurred in water year 2007 at both sites. Base-flow and stormwater samples were collected and analyzed for suspended solids, total phosphorus, and ammonia nitrogen. For both Eagle and Joos Valley Creeks the median concentrations of suspended solids and total phosphorus in base flow were lower during the post-BMP period compared to the pre-BMP period and were statistically significant at the 0.05 significance level. The decrease in median concentrations of ammonia nitrogen at both sites was not statistically significant at the 0.05 significance level. Multiple linear regression analyses were used to remove the effects of climatologic conditions and seasonality from computed storm loads. For both Eagle and Joos Valley Creeks, the median storm loads for suspended solids, total phosphorus, and ammonia nitrogen were lower during the post-BMP period compared to the pre-BMP period and were statistically significant at the 0.05 significance level. The decreases in storm-load regression residuals from the pre- to the post-BMP periods for both Eagle and Joos Valley Creeks were statistically significant for all three constituents at the 0.05 significance level and indicated an apparent improvement in water-quality in the post-BMP period. Because the rainfall characteristics for individual storms in the pre- and post-BMP periods are likely to be different, separate pre- and post-BMP regressions were used to estimate the theoretical pre- and post-BMP storm loads to allow estimates of precent reductions between the pre- and post-BMP periods. The estimated percent reductions in storm loads for suspended solids, total phosphorus, and ammonia nitrogen were 89, 77, and 66 respectively for Eagle Creek and 84, 67, and 60 respectively for Joos Valley Creek. The apparent improvement in water quality is attributed to the implemented BMPs and to a reduction in the number of cattle in the watersheds.
LoVetere, Sara H.; Nordstrom, D. Kirk; Maest, Ann S.; Naus, Cheryl A.
2003-01-01
Historical ground-water quality data for 100 wells in the Red River Valley between the U.S. Geological Survey streamflow-gaging station (08265000), near Questa, and Placer Creek east of the town of Red River, New Mexico, were compiled and reviewed. The tabulation included 608 water-quality records from 23 sources entered into an electronic database. Groundwater quality data were first collected at the Red River wastewater-treatment facility in 1982. Most analyses, however, were obtained between 1994 and 2002, even though the first wells were developed in 1962. The data were evaluated by considering (a) temporal consistency, (b) quality of sampling methods, (c) charge imbalance, and (d) replicate analyses. Analyses that qualified on the basis of these criteria were modeled to obtain saturation indices for gypsum, calcite, fluorite, gibbsite, manganite, and rhodocrosite. Plots created from the data illustrate that water chemistry in the Red River Valley is predominantly controlled by calcite dissolution, congruent gypsum dissolution, and pyrite oxidation.
Salts in the dry valleys of Antartica
NASA Technical Reports Server (NTRS)
Gibson, E. K., Jr.; Presley, B. J.; Hatfield, J.
1984-01-01
The Dry Valleys of Antarctica are examples of polar deserts which are rare geological features on the Earth. Such deserts typically have high salinities associated with their closed-basin waters and on many surficial materials throughout them. In order to examine the possible sources for the salts observed in association with the soils in the Dry Valleys. The chloride and bromide concentrations of the water leachates from 58 soils and core samples were measured. The Cl/Br ratio for seawater is 289 and ratios measured for most of the 58 soils studied (greater than 85% of the soils studied) was larger than the seawater ratio (ratios typically were greater than 1000 and ranged up to 50,000). The enrichment in Cl relative to Br is strong evidence that the alts present within the soils were derived from seawater during ordinary evaporation processes, and not from the deposition of Cl and Br from aerosols or from rock weathering as has often been suggested.
Zhang, Xingxiao; Jiang, Shijin; Wu, Jiaqiang; Zhao, Qin; Sun, Yani; Kong, Yibo; Li, Xiaoxia; Yao, Meiling; Chai, Tongjie
2009-01-13
The co-infection of duck circovirus (DuCV) with Riemerella anatipestifer (RA) or/and Escherichia coli (E. coli) or/and duck hepatitis virus I (DHV-I) in Cherry Valley ducks in China's Shandong Province was investigated by using polymerase-chain-reaction (PCR)-based methods. For this study, 742 ducks sampled at random from 70 duck farms during 2006-2007 were examined using PCR and dot-blot hybridisation (DBH) tests. Overall the DuCV infection rate was 33.29%. Compared with those at 2 weeks of age, the ducks at 3-4 weeks of age were more susceptible to DuCV infection. Compared with the DuCV-negative ones, the DuCV-positive ducks had a higher rate of infection by DHV-I (25.5% vs. 7.475%), RA (23.48% vs. 8.28%) and E. coli (16.19% vs. 4.85%). This investigation shows that DuCV infection is common in Cherry Valley ducks on some farms in Shandong Province.
Trion fine structure and coupled spin–valley dynamics in monolayer tungsten disulfide
Plechinger, Gerd; Nagler, Philipp; Arora, Ashish; Schmidt, Robert; Chernikov, Alexey; del Águila, Andrés Granados; Christianen, Peter C.M.; Bratschitsch, Rudolf; Schüller, Christian; Korn, Tobias
2016-01-01
Monolayer transition-metal dichalcogenides have recently emerged as possible candidates for valleytronic applications, as the spin and valley pseudospin are directly coupled and stabilized by a large spin splitting. The optical properties of these two-dimensional crystals are dominated by tightly bound electron–hole pairs (excitons) and more complex quasiparticles such as charged excitons (trions). Here we investigate monolayer WS2 samples via photoluminescence and time-resolved Kerr rotation. In photoluminescence and in energy-dependent Kerr rotation measurements, we are able to resolve two different trion states, which we interpret as intravalley and intervalley trions. Using time-resolved Kerr rotation, we observe a rapid initial valley polarization decay for the A exciton and the trion states. Subsequently, we observe a crossover towards exciton–exciton interaction-related dynamics, consistent with the formation and decay of optically dark A excitons. By contrast, resonant excitation of the B exciton transition leads to a very slow decay of the Kerr signal. PMID:27586517
Ancient palace complex (300–100 BC) discovered in the Valley of Oaxaca, Mexico
Redmond, Elsa M.; Spencer, Charles S.
2017-01-01
Recently completed excavations at the site of El Palenque in Mexico’s Valley of Oaxaca have recovered the well-preserved remains of a palace complex dated by associated radiocarbon samples and ceramics to the Late Formative period or Late Monte Albán I phase (300–100 BC), the period of archaic state emergence in the region. The El Palenque palace exhibits certain architectural and organizational features similar to the royal palaces of much later Mesoamerican states described by Colonial-period sources. The excavation data document a multifunctional palace complex covering a maximum estimated area of 2,790 m2 on the north side of the site’s plaza and consisting of both governmental and residential components. The data indicate that the palace complex was designed and built as a single construction. The palace complex at El Palenque is the oldest multifunctional palace excavated thus far in the Valley of Oaxaca. PMID:28348218
Jenkins, Jill A.; Draugelis-Dale, Rassa O.
2006-01-01
The Sonny Bono Salton Sea National Wildlife Refuge (SSNWR) is located 64 km north of the Mexican border at the southern end of the Salton Sea in California's Imperial Valley. Freshwater ponds and managed habitats at the SSNWR, Calipatria, Calif. are supplied with Colorado River water that carries compounds from upstream sources. Components include municipal and industrial discharges, agricultural drainage, and sewage plant inputs. Aquatic animals in these ecosystems are continuously exposed to multiple constituents, several of which have been demonstrated to be associated with hormonal disturbances. We investigated possible endocrine impacts to fish in the Imperial Valley, Calif., by addressing the null hypothesis that aquatic species in impacted sites did not exhibit evidence of endocrine disruption as compared with those from nonimpacted sites. The results presented are intended to provide managers with science-based information and interpretations about the condition of the animals in their ecosystems for the minimization of potential adverse effects to trust fish and wildlife resources and for the maximization of available water resources.
NASA Astrophysics Data System (ADS)
Valer, Marina; Schiano, Pierre; Bachèlery, Patrick
2017-09-01
Major and trace element compositions were obtained for bulk rocks and melt inclusions hosted in olivine crystals (Fo > 85) from the adventive cones of the Piton de La Fournaise volcano (La Réunion Island). Ratios of highly incompatible trace elements for these magmas are used to identify the nature of the La Réunion mantle plume source. Although adventive cone lavas display unusual major element compositions compared to the historical lavas of the volcano (e.g., lower CaO/Al2O3), trace element data suggest that the magmas emitted by the adventive cones originate from a common chemical source. This source may correspond to either a homogeneous mixed source of different mantle components or a near-primitive less-differentiated mantle source. The melt inclusions display ratios of highly incompatible elements (e.g., Th/La, Nb/La) which are similar to primitive mantle values, and lower Nb/U ratios compared to most oceanic basalts. These results and previous isotopic and trace element data suggest that La Réunion plume samples a source which is intermediate between a primitive-like mantle domain and a slightly depleted one almost unaffected by the recycling processes. This source could have originated from early depletion of the primitive mantle. Assuming a depletion 4.45 Gyr ago, 10% melting of this slightly depleted source could explain the enriched trace element concentrations of the melt inclusions.
Ground-water quality and geochemistry in Dayton, Stagecoach, and Churchill Valleys, western Nevada
Thomas, James M.; Lawrence, Stephen J.
1994-01-01
The U.S. Geological Survey investigated the quality of ground water in the Dayton, Stagecoach, and Churchill Valleys as part of the Carson River Basin National Water-Quality Assessment (NAWQA) pilot study. Four aquifer systems have been de- lineated in the study area. Principal aquifers are unconsolidated deposits at altitudes of less than 4,900 feet above sea level and more than 50 feet below land surface. Shallow aquifers are at altitudes of less than 4,900 feet and less than 50 feet below land surface. Upland aquifers are above 4,900 feet and provide recharge to the principal aquifers. Thermal aquifers, defined as those having a water temperature greater than 30 degrees Celsius, are also present. Ground water used in Dayton, Stagecoach, and Churchill Valleys is pumped from principal aquifers in unconsolidated basin-fill deposits. Ground water in these aquifers originates as precipitation in the adjacent mountains and is recharged by the Carson River and by underflow from adjacent upstream valleys. Ground-water flow is generally parallel to the direction of surface-water flow in the Carson River. Ground water is discharged by pumping, evapo- transpiration, and underflow into the Carson River. The results of geochemical modeling indicate that as ground water moves from upland aquifers in mountainous recharge areas to principal aquifers in basin-fill deposits, the following processes probably occur: (1) plagioclase feldspar, sodium chloride, gypsum (or pyrite), potassium feldspar, and biotite dissolve; (2) calcite precipitates; (3) kaolinite forms; (4) small amounts of calcium and magnesium in the water exchange for potassium on aquifer minerals; and (5) carbon dioxide is gained or lost. The geochemical models are consistent with (1) phases identified in basin- fill sediments; (2) chemical activity of major cations and silica; (3) saturation indices of calcite and amorphous silica; (4) phase relations for aluminosilicate minerals indicated by activity diagrams; and (5) results of optical, X-ray diffraction, and scanning-electron microscopy examination of mineral grains in the aquifer sediments. Sulfur-isotopic composition of ground- water samples also supports the models. In general, the quality of ground water in the study area meets Nevada State drinking-water standards and is acceptable for most uses. In addition to analysis for major ions, samples were analyzed for 22 inorganic trace elements, 3 nutrients, and 4 radionuclides. Selenium in 1 sample is the only constituent that exceeded Nevada State primary drinking-water standards. Nevada State secondary- drinking water standards were exceeded for fluoride in 1 sample, for iron in 7 samples, and for manganese in 19 samples. Minor constituent con- centrations are generally the result of local redox conditions, and are primarily from minerals in volcanic and marine metasedimentary rocks, metal- oxide coatings on mineral grains, and organic matter.
Ground-water resources of the Caguas-Juncos Valley, Puerto Rico
Puig, J.C.; Rodriguez, J.M.
1993-01-01
?The Caguas-Juncos valley, which occupies an area of 35 square miles in east-central Puerto Rico, is underlain by the largely unconfined alluvial aquifer. Withdrawals from this aquifer for public water supply and for agricultural, industrial, and domestic water uses totalled about 3.0 million gallons per day in 1988. Some wells in the valley yield as much as 310 gallons per minute from the alluvial deposits along Rio Gurabo near Gurabo and near Juncos. Wells used at dairy farms in the area commonly yield about 30 gallons per minute. The potentiometric surface of the alluvial aquifer varies seasonally and generally is highest near the end of December and lowest in April. Transmissivity of the alluvial aquifer, estimated from specific capacity and slug test data, ranges from 65 to 4,800 feet squared per day. The estimated specific yield of the water-table is about 10 to 15 percent. The amount of water stored in the aquifer is estimated to be about 122,000 acre-feet. Analyses of ground-water samples revealed the presence of two distinct problems-- high natural concentrations of iron and manganese, and localized areas of human- related contamination scattered throughout the valley. The ground water is a calcium-bicarbonate type and typically has dissolved solids concentrations of less than 500 milligrams per liter.
Lindblom, Ronald A; Reichart, Letitia M; Mandernack, Brett A; Solensky, Matthew; Schoenebeck, Casey W; Redig, Patrick T
2017-10-01
Lead poisoning of scavenging raptors occurs primarily via consumption of game animal carcasses containing lead, which peaks during fall firearm hunting seasons. We hypothesized that snowfall would mitigate exposure by concealing carcasses. We categorized blood lead level (BLL) for a subsample of Bald Eagles (Haliaeetus leucocephalus) from the Upper Mississippi River Valley and described BLL with respect to age, sex, and snowfall. We captured Bald Eagles overwintering in the Upper Mississippi River Valley (n=55) between December 1999 and January 2002. Individual BLL ranged from nondetectable to 335 μg/dL, with 73% of the samples testing positive for acute exposure to lead. Eagle BLL did not significantly differ between age or sex, but levels were higher immediately following the hunting season, and they were lower when the previous month's snowfall was greater than 11 cm. This study suggests a window of time between the white-tailed deer (Odocoileus virginianus) hunting season and the onset of snow when the population experienced peak exposure to lead. Combining these findings with existing research, we offer a narrative of the annual lead exposure cycle of Upper Mississippi River Valley Bald Eagles. These temporal associations are necessary considerations for accurate collection and interpretation of BLL.
Moran, Edward H.; Solin, Gary L.
2006-01-01
The Matanuska-Susitna Valley is in the northeastern part of the Cook Inlet Basin, Alaska, an area experiencing rapid population growth and development proximal to many lakes. Here water commonly flows between lakes and ground water, indicating interrelation between water quantity and quality. Thus concerns exist that poorer quality ground water may degrade local lake ecosystems. This concern has led to water-quality sampling in cooperation with the Alaska Department of Environmental Conservation and the Matanuska-Susitna Borough. A map showing the estimated altitude of the water table illustrates potential ground-water flow directions and areas where ground- and surface-water exchanges and interactions might occur. Water quality measured in selected wells and lakes indicates some differences between ground water and surface water. 'The temporal and spatial scarcity of ground-water-level and water-quality data limits the analysis of flow direction and water quality. Regionally, the water-table map indicates that ground water in the eastern and southern parts of the study area flows southerly. In the northcentral area, ground water flows predominately westerly then southerly. Although ground and surface water in most areas of the Matanuska-Susitna Valley are interconnected, they are chemically different. Analyses of the few water-quality samples collected in the area indicate that dissolved nitrite plus nitrate and orthophosphorus concentrations are higher in ground water than in surface water.'
Radtke, D.B.; Kepner, W.G.; Effertz, R.J.
1988-01-01
The Lower Colorado River Valley Irrigation Drainage Project area included the Colorado River and its environs from Davis Dam to just above Imperial Dam. Water, bottom sediment, and biota were sampled at selected locations within the study area and analyzed for selected inorganic and synthetic organic constituents that are likely to be present at toxic concentrations. With the exceptions of selenium and DDE, this study found sampling locations to be relatively free of large concentrations of toxic constituents that could be a threat to humans, fish, and wildlife. Selenium was the only inorganic constituent to exceed any existing standard, criterion, or guideline for protection of fish and wildlife resources. Concentrations of DDE in double-crested cormorants, however, exceeded the criterion of 1.0 microgram per gram established by the National Academy of Sciences and the National Academy of Engineering for DDT and its metabolites for protection of wildlife. Dissolved-selenium concentrations in water from the lower Colorado River appear to be derived from sources above Davis Dam. At this time, therefore , agricultural practices in the lower Colorado River valley do not appear to exacerbate selenium concentrations. This fact, however, does not mean that the aquatic organisms and their predators are not in jeopardy. Continued selenium loading to the lower Colorado environment could severely affect important components of the ecosystem. (Author 's abstract)
Iko, W.M.; Archuleta, A.S.; Knopf, F.L.
2003-01-01
Declines of over 60% in mountain plover (Charadrius montanus) populations over the past 30 years have made it a species of concern throughout its current range and a proposed species for listing under the U.S. Endangered Species Act. Wintering mountain plovers spend considerable time on freshly plowed agricultural fields where they may potentially be exposed to anticholinesterase pesticides. Because of the population status and wintering ecology of plovers, the objectives of our study were to use nondestructive methods to report baseline plasma cholinesterase (ChE) levels in free-ranging mountain plovers wintering in California, USA, and to assess whether sampled birds showed signs of ChE inhibition related to anticholinesterase chemical exposure. We compared plasma ChE activity for mountain plovers sampled from the Carrizo Plain (an area relatively free of anticholinesterase pesticide use) with similar measures for plovers from the Central Valley (where anticholinesterase pesticides are widely used). Analyses for ChE inhibition indicated that none of the plovers had been recently exposed to these chemicals. However, mean ChE levels of plovers from the Central Valley were significantly higher (32%) than levels reported for plovers from the Carrizo Plain. This result differs from our original assumption of higher exposure risk to mountain plovers in the Central Valley but does suggest that some effect is occurring in the ChE activity of mountain plovers wintering in California.
A process-based hierarchical framework for monitoring glaciated alpine headwaters
Weekes, Anne A.; Torgersen, Christian E.; Montgomery, David R.; Woodward, Andrea; Bolton, Susan M.
2012-01-01
Recent studies have demonstrated the geomorphic complexity and wide range of hydrologic regimes found in alpine headwater channels that provide complex habitats for aquatic taxa. These geohydrologic elements are fundamental to better understand patterns in species assemblages and indicator taxa and are necessary to aquatic monitoring protocols that aim to track changes in physical conditions. Complex physical variables shape many biological and ecological traits, including life history strategies, but these mechanisms can only be understood if critical physical variables are adequately represented within the sampling framework. To better align sampling design protocols with current geohydrologic knowledge, we present a conceptual framework that incorporates regional-scale conditions, basin-scale longitudinal profiles, valley-scale glacial macroform structure, valley segment-scale (i.e., colluvial, alluvial, and bedrock), and reach-scale channel types. At the valley segment- and reach-scales, these hierarchical levels are associated with differences in streamflow and sediment regime, water source contribution and water temperature. Examples of linked physical-ecological hypotheses placed in a landscape context and a case study using the proposed framework are presented to demonstrate the usefulness of this approach for monitoring complex temporal and spatial patterns and processes in glaciated basins. This approach is meant to aid in comparisons between mountain regions on a global scale and to improve management of potentially endangered alpine species affected by climate change and other stressors.
2010-03-25
Luna 16 was the first robotic mission to land on the Moon on basaltic plains of Mare Fecunditatis and return a sample to the Earth. It was launched by the Soviet Union on 12 September 1970. This image was taken by NASA Lunar Reconnaissance Orbiter.
Soviet Union Lunar Sample Return Missions
2010-03-15
On February 21, 1972, Luna 20 soft landed in the rugged highlands between Mare Fecunditatis and Mare Crisium. The Luna 20 descent stage still sits silently on the Moon, clearly visible in this image taken by NASA Lunar Reconnaissance Orbiter.
Devos, Christophe; David, Frank; Sandra, Pat
2012-10-26
According to recent directives of the European Union (EU), limits of quantification (LOQ) for the determination of tributyltin (TBT) in surface waters should be ca. 60 pg/L (ppq). This put very stringent requirements on analytical methodologies; definitely when they have to be applied in a routine environment. Stir bar sorptive extraction (SBSE), followed by thermal desorption (TD) and capillary gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) can provide accurate and precise data at the 2 ng/L level (ppt). For lower concentrations, matrix and reagent interferences together with contamination may provide too high TBT values. A two-dimensional heart-cut GC method was developed to fractionate TBT from interferences. The GC-GC-MS/MS method shows excellent linearity in the range 50 pg/L-4 ng/L, good repeatability (RSD<20% at 200 pg/L), and a limit of detection of 11 pg/L. The method performance is demonstrated with representative samples i.e. harbor water and waste water samples. Copyright © 2012 Elsevier B.V. All rights reserved.
Sloto, Ronald A.; McManus, B. Craig
1996-01-01
Valley Forge National Historical Park is just southwest of the Commodore Semiconductor Group (CSG) National Priorities List (Superfund) Site, a source of volatile organic compounds (VOC's) in ground water. The 7.5-square-mile study area includes the part of the park in Lower Providence and West Norriton Townships in Montgomery County, Pa., and surrounding vicinity. The park is underlain by sedimentary rocks of the Upper Triassic age stockton Formation. A potentiometric-surface map constructed from water levels measured in 59 wells shows a cone of depression, approximately 0.5 mile in diameter, centered near the CSG Site. The cone of depression is caused by the pumping of six public supply wells. A ground-water divide between the cone of depression and Valley Forge National Historical Park provides a hydraulic barrier to the flow of ground water and contaminants from the CSG Site to the park. If pumping in the cone of depression was to cease, water levels would recover, and the ground-water divide would shift to the north. A hydraulic gradient between the CSG Site and the Schuylkill River would be established, causing contaminated ground water to flow to the park.Water samples were collected from 12 wells within the park boundary and 9 wells between the park boundary and the ground-water divide to the north of the park. All water samples were analyzed for physical properties (field determinations), nutrients, common ions, metals and other trace constituents, and VOC's. Water samples from the 12 wells inside the park boundary also were analyzed for pesticides. Concentrations of inorganic constituents in the water samples did not exceed U.S. Environmental Protection Agency maximum contaminant levels. Very low concentrations of organic compounds were detected in some of the water samples. VOC's were detected in water from 76 percent of the wells sampled; the maximum concentration detected was 5.8 micrograms per liter of chloroform. The most commonly detected VOC was chloroform. The second most commonly detected compound was methyl tert-butyl ether (MTBE), which was detected in water from 24 percent of wells sampled. Several pesticides were detected in water samples collected from within the park boundaries.: chlordane, DDD, dieldrin, endrin, heptachlor epoxide, and simazine. Concentrations of the detected pesticides were 0.1 micrograms per liter or less and did not exceed U.S. Environmental Protection Agency maximum contaminant levels.
Pearson, D.A.; Schaefer, T.; Johnson, K.R.; Nichols, D.J.
2001-01-01
New data from 17 Cretaceous-Tertiary (K-T) boundary sections and 53 vertebrate sites in the Hell Creek and Fort Union Formations in southwestern North Dakota document a 1.76 m barren interval between the highest Cretaceous vertebrate fossils and the palynologically recognized K-T boundary. The boundary is above the formational contact at 15 localities and coincident with it at two, demonstrating that the formational contact is diachronous. Dinosaurs are common in the highest Cretaceous vertebrate samples and a partial dinosaur skeleton in the Fort Union Formation is the highest recorded Cretaceous vertebrate fossil in this area.
Nolte, Christopher G; Schauer, James J; Cass, Glen R; Simoneit, Bernd R T
2002-10-15
Source sample extracts of vegetative detritus, motor vehicle exhaust, tire dust paved road dust, and cigarette smoke have been silylated and analyzed by GC-MS to identify polar organic compounds that may serve as tracers for those specific emission sources of atmospheric fine particulate matter. Candidate molecular tracers were also identified in atmospheric fine particle samples collected in the San Joaquin Valley of California. A series of normal primary alkanols, dominated by even carbon-numbered homologues from C26 to C32, the secondary alcohol 10-nonacosanol, and some phytosterols are prominent polar compounds in the vegetative detritus source sample. No new polar organic compounds are found in the motor vehicle exhaust samples. Several hydrogenated resin acids are present in the tire dust sample, which might serve as useful tracers for those sources in areas that are heavily impacted by motor vehicle traffic. Finally, the alcohol and sterol emission profiles developed for all the source samples examined in this project are scaled according to the ambient fine particle mass concentrations attributed to those sources by a chemical mass balance receptor model that was previously applied to the San Joaquin Valley to compute the predicted atmospheric concentrations of individual alcohols and sterols. The resulting underprediction of alkanol concentrations at the urban sites suggests that alkanols may be more sensitive tracers for natural background from vegetative emissions (i.e., waxes) than the high molecular weight alkanes, which have been the best previously available tracers for that source.
NASA Astrophysics Data System (ADS)
Viero, Alessia; Marchi, Lorenzo; Cavalli, Marco; Crema, Stefano; Fontana, Alessandro; Mozzi, Paolo; Venturini, Corrado
2016-04-01
Alluvial sediment investigations provide fundamental tools to infer the processes that control geomorphological evolution of mountain environments. By analyzing sediment stratigraphy in depth, it is possible to retrieve the source, the geology, the time of deposition, the relative distance travelled by material as well as to distinguish among different type of transport (i.e., gravitational, fluvial or glacial). In this work, we present a combination of log stratigraphy, radiocarbon dating and geophysical surveys carried out on the valley floor of the But River (Carnic Alps, North East Italy). The But River basin drains an area of 326 km2 with a range in elevation from 2769 to 323 m a.s.l.; the bedrock mainly consists of carbonates and quartz arenites with minor inclusions of effusive rocks. After Pleistocene the gravitational deposits from mountain slopes have impounded the But River several times. In particular, we analyzed a sector of the upper portion of the But valley close to the confluence of the Moscardo Torrent, frequently affected by debris flows. A borehole was drilled in the But River floodplain, at the intersection with the Moscardo Torrent alluvial fan, down to a depth of 80 m. The analysis of the core samples allowed discerning three sedimentary levels rich in clay and organic materials, which testify the presence of small dam lakes, originated from the Moscardo debris-flow deposits. Three samples of wood and plant debris were collected from 13, 14 and 23 m of depth, respectively. They were analyzed through radiocarbon dating in order to determine the age of the lakes and, thus, to infer the activity of the debris flows building the Moscardo cone. The calibrated ages of the 3 samples are close to the younger limit of the radiocarbon method indicating a fast aggradation of the valley floor, starting from a period ranging between 1450 - 1632 AD. Historical maps and documents confirm the presence of the lakes until 19th century and they permit to assess their extent and the maximum depths. Two passive seismic campaigns were carried out near the borehole site and along the But valley at different elevations. The aim was to investigate the depth of the buried bedrock and therefore to indirectly characterize the thickness of alluvial deposits. We calibrated the fundamental frequency of each site by constraining average shear velocity of the alluvial sediments close to the borehole site with known stratigraphy. Eight HVSR (Horizontal to Vertical Spectral Ratio, Nakamura, 1989) were carried out, and thus a first sketch of the buried valley floor along a longitudinal profile of about 5 km was depicted. The values of the derived bedrock depth allow to quantify the differences in thickness between the alluvial deposits and the Moscardo Torrent fan deposits. This information helps to address the contribution of the debris-flow processes in damming the upper But River during the last five centuries. The results confirm the role of debris-flow deposits from the Moscardo Torrent in shaping the morphology of the valley floor of But River and show suitability of an integrated approach, encompassing log stratigraphy, geophysical surveys and analysis of historical documents, for gaining insights on the evolution of alpine valleys. Reference Nakamura, Y., 1989. A method for dynamic characteristic estimation of subsurface using microtremor on the ground surface. Quarterly Report of Railway Technical Research Institute, 30(1): 25-33.
Proton-Induced X-Ray Emission Analysis of Crematorium Emissions
NASA Astrophysics Data System (ADS)
Ali, Salina; Nadareski, Benjamin; Yoskowitz, Joshua; Labrake, Scott; Vineyard, Michael
2014-09-01
There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-MeV protons from the 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. We measured significant concentrations of sulfur, phosphorus, potassium, calcium, and iron, but essentially no mercury in the aerosol samples. The lower limit of detection for airborne mercury in this experiment was approximately 0.2 ng / m3. The PIXE analysis of the soil samples showed the presence of elements commonly found in soil (Si, K, Ca, Ti, Mn, Fe), but no trace of mercury. There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-MeV protons from the 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. We measured significant concentrations of sulfur, phosphorus, potassium, calcium, and iron, but essentially no mercury in the aerosol samples. The lower limit of detection for airborne mercury in this experiment was approximately 0.2 ng / m3. The PIXE analysis of the soil samples showed the presence of elements commonly found in soil (Si, K, Ca, Ti, Mn, Fe), but no trace of mercury. Union College Department of Physics and Astronomy.
Transform migration and vertical tectonics at the Romanche fracture zone, equatorial Atlantic
NASA Astrophysics Data System (ADS)
Bonatti, E.; Ligi, M.; Gasperini, L.; Peyve, A.; Raznitsin, Y.; Chen, Y. J.
1994-11-01
The Romanche transform offsets the Mid-Atlantic Ridge (MAR) axis by about 950 km in the equatorial Atlantic. Multibeam and high-resolution multichannel seismic reflection surveys as well as rock sampling were carried out on the eastern part of the transform with the R/V Akademik Strakhov as part of the Russian-Italian Mid-Atlantic Ridge Project (PRIMAR). Morphobathymetric data show the existence on the northern side of the transform of a major 800-km-long aseismic valley oriented 10 deg to 15 deg from the active valley; it disappears about 150 km from the western MAR segment. The aseismic valley marks probably the former location of the Romanche transform ('PaleoRomanche') that was active up to roughly 8-10 Ma, when the transform boundary migrated to its present position. A temporary microplate developed during the migration and reorientation of the transform. This microplate changed its sense of motion as it was transferred from the South American to the African plate. Evaluation of the seismic reflection data as well as study of samples of carbonates, ventifact basaltic pebbles and gabbroic, peridotitic and basaltic rocks recovered at different sites on the transverse ridge, suggest that (1) the summit of the transverse ridge was above sea level at and before about 5 Ma; (2) the transverse ridge subsided since then at an average rate 1 order of magnitude faster than the predicted thermal contraction rate; its summit was flattened by erosion at sea level during subsidence; (3) the transverse ridge is an uplifted sliver of lithosphere and not a volcanic constructional feature; and (4) transtensional and transpressional tectonics have affected the transverse ridge. Uplift may have been caused primarily by thrust faulting induced by transpression related to the oblique impact of the lithospheric plate against the former (PaleoRomanche) and the younger transform boundaries, before and during the transition to the present boundary. After migration of the transform boundary to its present position, transpression was replaced by transtension and by subsidence of the transverse ridge. An aseismic axial rift valley impacting against the transform valley about 80 km west of the present RTI suggests eastward ridge jumping and probably followed transform migration. Localized transtension or transpression due to bends in the orientation of the transform may have caused intense although localized vertical movements, such as those that formed an ultradeep (greater than 7800 m) pull-apart basin along the transform valley.
NASA Astrophysics Data System (ADS)
Obryk, M.; Doran, P. T.; Priscu, J. C.; Morgan-Kiss, R. M.; Siebenaler, A. G.
2012-12-01
The perennially ice-covered lakes in the McMurdo Dry Valleys, Antarctica have been extensively studied under the Long Term Ecological Research project. But sampling has been spatially restricted due to the logistical difficulty of penetrating the 3-6 m of ice cover. The ice covers restrict wind-driven turbulence and its associated mixing of water, resulting in a unique thermal stratification and a strong vertical gradient of salinity. The permanent ice covers also shade the underlying water column, which, in turn, controls photosynthesis. Here, we present results of a three-dimensional record of lake processes obtained with an autonomous underwater vehicle (AUV). The AUV was deployed at West Lake Bonney, located in Taylor Valley, Dry Valleys, to further understand biogeochemical and physical properties of the Dry Valley lakes. The AUV was equipped with depth, conductivity, temperature, under water photosynthetically active radiation (PAR), turbidity, chlorophyll-and-DOM fluorescence, pH, and REDOX sensors. Measurements were taken over the course of two years in a 100 x 100 meter spaced horizontal sampling grid (and 0.2 m vertical resolution). In addition, the AUV measured ice thickness and collected 200 images looking up through the ice, which were used to quantify sediment distribution. Comparison with high-resolution satellite QuickBird imagery demonstrates a strong correlation between aerial sediment distribution and ice cover thickness. Our results are the first to show the spatial heterogeneity of lacustrine ecosystems in the McMurdo Dry Valleys, significantly improving our understanding of lake processes. Surface sediment is responsible for localized thinning of ice cover due to absorption of solar radiation, which in turn increases total available PAR in the water column. Higher PAR values are negatively correlated with chlorophyll-a, presenting a paradox; historically, long-term studies of PAR and chlorophyll-a have shown positive trends. We hypothesized that this paradox is a result of short-term photoadaptation of phytoplanktonic communities to spatial and temporal variations of PAR within the water column. To test this hypothesis, we established phytoplankton enrichment cultures from depths of maximum primary production (13 m) and tested whether dry valley lake phytoplankton respond to daily variations in controlled light environment. Laboratory-grown cultures exhibited a strong response at 12 hr:12 hr day:night cycle at the level of both photochemistry and chlorophyll biosynthesis, indicating that Lake Bonney possess the ability to quickly respond to changes in their light environment.
A regional-scale study of chromium and nickel in soils of northern California, USA
Morrison, J.M.; Goldhaber, M.B.; Lee, L.; Holloway, J.M.; Wanty, R.B.; Wolf, R.E.; Ranville, J.F.
2009-01-01
A soil geochemical survey was conducted in a 27,000-km2 study area of northern California that includes the Sierra Nevada Mountains, the Sacramento Valley, and the northern Coast Range. The results show that soil geochemistry in the Sacramento Valley is controlled primarily by the transport and weathering of parent material from the Coast Range to the west and the Sierra Nevada to the east. Chemically and mineralogically distinctive ultramafic (UM) rocks (e.g. serpentinite) outcrop extensively in the Coast Range and Sierra Nevada. These rocks and the soils derived from them have elevated concentrations of Cr and Ni. Surface soil samples derived from UM rocks of the Sierra Nevada and Coast Range contain 1700-10,000 mg/kg Cr and 1300-3900 mg/kg Ni. Valley soils west of the Sacramento River contain 80-1420 mg/kg Cr and 65-224 mg/kg Ni, reflecting significant contributions from UM sources in the Coast Range. Valley soils on the east side contain 30-370 mg/kg Cr and 16-110 mg/kg Ni. Lower Cr and Ni concentrations on the east side of the valley are the result of greater dilution by granitic sources of the Sierra Nevada. Chromium occurs naturally in the Cr(III) and Cr(VI) oxidation states. Trivalent Cr is a non-toxic micronutrient, but Cr(VI) is a highly soluble toxin and carcinogen. X-ray diffraction and scanning electron microscopy of soils with an UM parent show Cr primarily occurs within chromite and other mixed-composition spinels (Al, Mg, Fe, Cr). Chromite contains Cr(III) and is highly refractory with respect to weathering. Comparison of a 4-acid digestion (HNO3, HCl, HF, HClO4), which only partially dissolves chromite, and total digestion by lithium metaborate (LiBO3) fusion, indicates a lower proportion of chromite-bound Cr in valley soils relative to UM source soils. Groundwater on the west side of the Sacramento Valley has particularly high concentrations of dissolved Cr ranging up to 50 ??g L-1 and averaging 16.4 ??g L-1. This suggests redistribution of Cr during weathering and oxidation of Cr(III)-bearing minerals. It is concluded that regional-scale transport and weathering of ultramafic-derived constituents have resulted in enrichment of Cr and Ni in the Sacramento Valley and a partial change in the residence of Cr.
Mills, Christopher T.; Morrison, Jean M.; Goldhaber, Martin B.; Ellefsen, Karl J.
2011-01-01
Concentrations of geogenic Cr(VI) in groundwater that exceed the World Health Organization’s maximum contaminant level for drinking water (50 μg L−1) occur in several locations globally. The major mechanism for mobilization of this Cr(VI) at these sites is the weathering of Cr(III) from ultramafic rocks and its subsequent oxidation on Mn oxides. This process may be occurring in the southern Sacramento Valley of California where Cr(VI) concentrations in groundwater can approach or exceed 50 μg L−1. To characterize Cr geochemistry in the area, samples from several soil auger cores (approximately 4 m deep) and drill cores (approximately 25 m deep) were analyzed for total concentrations of 44 major, minor and trace elements, Cr associated with labile Mn and Fe oxides, and Cr(VI). Total concentrations of Cr in these samples ranged from 140 to 2220 mg per kg soil. Between 9 and 70 mg per kg soil was released by selective extractions that target Fe oxides, but essentially no Cr was associated with the abundant reactive Mn oxides (up to ~1000 mg hydroxylamine-reducible Mn per kg soil was present). Both borehole magnetic susceptibility surveys performed at some of the drill core sites and relative differences between Cr released in a 4-acid digestion versus total Cr (lithium metaborate fusion digestion) suggest that the majority of total Cr in the samples is present in refractory chromite minerals transported from ultramafic exposures in the Coast Range Mountains. Chromium(VI) in the samples studied ranged from 0 to 42 μg kg−1, representing a minute fraction of total Cr. Chromium(VI) content was typically below detection in surface soils (top 10 cm) where soil organic matter was high, and increased with increasing depth in the soil auger cores as organic matter decreased. Maximum concentrations of Cr(VI) were up to 3 times greater in the deeper drill core samples than the shallow auger cores. Although Cr(VI) in these vadose zone soils and sediments was only a very small fraction of the total solid phase Cr, they are a potentially important source for Cr(VI) to groundwater. Enhanced groundwater recharge through the vadose zone due to irrigation could carry Cr(VI) from the vadose zone to the groundwater and may be the mechanism responsible for the correlation observed between elevated Cr(VI) and NO3- source concentrations in previously published data for valley groundwaters. Incubation of a valley subsoil showed a Cr(VI) production rate of 24 μg kg−1 a−1 suggesting that field Cr(VI) concentrations could be regenerated annually. Increased Cr(VI) production rates in H+-amended soil incubations indicate that soil acidification processes such as nitrification of ammonium in fertilizers could potentially increase the occurrence of geogenic Cr(VI) in groundwater. Thus, despite the natural origin of the Cr, Cr(VI) generation in the Sacramento Valley soils and sediments has the potential to be influenced by human activities.
Stogner, Sr., Robert W.
2001-01-01
The first documented analysis of nitrate concentrations for ground water in the unconfined aquifer was done in 1936. This valleywide investigation indicated that nitrate concentrations were 0.3 milligram per liter or less in water-quality samples from 38 wells completed in the unconfined aquifer. A valleywide study conducted in the late 1940's documented the first occurrences of nitrate concentrations greater than 3 mg/L. Up to this time, soil fertility was maintained primarily through the use of cattle and (or) sheep manure and crop rotation. Subsequent valleywide studies have documented several occurrences of elevated nitrate concentrations in the unconfined aquifer in a localized, intensively cultivated area north of the Rio Grande. The nitrate concentrations in water appear to have changed in response to increasing use of commercial inorganic fertilizers after the mid-1940's. A 1993 valleywide study evaluated the potential health risk associated with elevated nitrate concentrations in domestic water supplies. Water-quality samples from 14 percent of the wells sampled contained nitrate concentrations greater than 10 milligrams per liter. Most of the samples that contained concentrations greater than 10 milligrams per liter were collected from wells located in the intensively cultivated area north of the Rio Grande. During the 1990's, several local, small-scale, and field-scale investigations were conducted in the intensively cultivated area north of the Rio Grande. These studies identified spatial and temporal variations in nitrate concentration and evaluated the effectiveness of using shallow monitoring wells to determine nitrate leaching. Variations in nitrate concentration were attributed, in part, to seasonal recharge of the aquifer by surface water with low nitrate concentrations. Shallow monitoring wells were effective for determining the amount of nitrate leached, but because of the amount of residual nitrate in the soil from previous seasons, were ineffective in evaluating variations in the amount of nitrate leaching associated with differences in application rates. It was concluded that irrigation practices have the greatest effect on leaching of nitrate to the aquifer. Management tools, such as irrigation scheduling, center-pivot sprinkler systems, soil and ground-water nitrogen credits, and cultivation of cover and winter crops, are being used to help maintain crop quality and yields while minimizing the potential of leaching and reducing residual nitrogen left in the soil. Review of available data from previous studies indicates that most of the sampled wells with elevated nitrate concentrations are located in the intensively cultivated area north of the Rio Grande. This area represents about 10 percent of the San Luis Valley and approximately 35 percent of the crop and pasture land in the valley. The area where nitrate concentrations exceed the U.S. Environmental Protection Agency drinking water maximum contaminant level represents about 150 square miles or 5 percent of the valley. Aquifer vulnerability to and contamination by pesticides was not evaluated until the 1990's. Risk analyses indicated that selected pesticides can pose a contamination threat to an unconfined aquifer in areas consisting primarily of sandy loam soil; sandy loam soils are common in the San Luis Valley. Water-quality samples collected from some wells during 1990 and 1993 indicated trace- to low-level pesticide contamination. The occurrence of pesticides was infrequent and isolated.
Geochemistry of the Birch Creek Drainage Basin, Idaho
Swanson, Shawn A.; Rosentreter, Jeffrey J.; Bartholomay, Roy C.; Knobel, LeRoy L.
2003-01-01
The U.S. Survey and Idaho State University, in cooperation with the U.S. Department of Energy, are conducting studies to describe the chemical character of ground water that moves as underflow from drainage basins into the eastern Snake River Plain aquifer (ESRPA) system at and near the Idaho National Engineering and Environmental Laboratory (INEEL) and the effects of these recharge waters on the geochemistry of the ESRPA system. Each of these recharge waters has a hydrochemical character related to geochemical processes, especially water-rock interactions, that occur during migration to the ESRPA. Results of these studies will benefit ongoing and planned geochemical modeling of the ESRPA at the INEEL by providing model input on the hydrochemical character of water from each drainage basin. During 2000, water samples were collected from five wells and one surface-water site in the Birch Creek drainage basin and analyzed for selected inorganic constituents, nutrients, dissolved organic carbon, tritium, measurements of gross alpha and beta radioactivity, and stable isotopes. Four duplicate samples also were collected for quality assurance. Results, which include analyses of samples previously collected from four other sites, in the basin, show that most water from the Birch Creek drainage basin has a calcium-magnesium bicarbonate character. The Birch Creek Valley can be divided roughly into three hydrologic areas. In the northern part, ground water is forced to the surface by a basalt barrier and the sampling sites were either surface water or shallow wells. Water chemistry in this area was characterized by simple evaporation models, simple calcite-carbon dioxide models, or complex models involving carbonate and silicate minerals. The central part of the valley is filled by sedimentary material and the sampling sites were wells that are deeper than those in the northern part. Water chemistry in this area was characterized by simple calcite-dolomite-carbon dioxide models. In the southern part, ground water enters the ESRPA. In this area, the sampling sites were wells with depths and water levels much deeper than those in the northern and central parts of the valley. The calcium and carbon water chemistry in this area was characterized by a simple calcite-carbon dioxide model, but complex calcite-silicate models more accurately accounted for mass transfer in these areas. Throughout the geochemical system, calcite precipitated if it was an active phase in the models. Carbon dioxide either precipitated (outgassed) or dissolved depending on the partial pressure of carbon dioxide in water from the modeled sites. Dolomite was an active phase only in models from the central part of the system. Generally the entire geochemical system could be modeled with either evaporative models, carbonate models, or carbonate-silicate models. In both of the latter types of models, a significant amount of calcite precipitated relative to the mass transfer to and from the other active phases. The amount of calcite precipitated in the more complex models was consistent with the amount of calcite precipitated in the simpler models. This consistency suggests that, although the simpler models can predict calcium and carbon concentrations in Birch Creek Valley ground and surface water, silicate-mineral-based models are required to account for the other constituents. The amount of mass transfer to and from the silicate mineral phases was generally small compared with that in the carbonate phases. It appears that the water chemistry of well USGS 126B represents the chemistry of water recharging the ESRPA by means of underflow from the Birch Creek Valley.
Estimation of salt loads for the Dolores River in the Paradox Valley, Colorado, 1980–2015
Mast, M. Alisa
2017-07-13
Regression models that relate total dissolved solids (TDS) concentrations to specific conductance were used to estimate salt loads for two sites on the Dolores River in the Paradox Valley in western Colorado. The salt-load estimates will be used by the Bureau of Reclamation to evaluate salt loading to the river coming from the Paradox Valley and the effect of the Paradox Valley Unit (PVU), a project designed to reduce the salinity of the Colorado River. A second-order polynomial provided the best fit of the discrete data for both sites on the river. The largest bias occurred in samples with elevated sulfate concentrations (greater than 500 milligrams per liter), which were associated with short-duration runoff events in late summer and fall. Comparison of regression models from a period of time before operation began at the PVU and three periods after operation began suggests the relation between TDS and specific conductance has not changed over time. Net salt gain through the Paradox Valley was estimated as the TDS load at the downstream site minus the load at the upstream site. The mean annual salt gain was 137,900 tons per year prior to operation of the PVU (1980–1993) and 43,300 tons per year after the PVU began operation (1997–2015). The difference in annual salt gain in the river between the pre-PVU and post-PVU periods was 94,600 tons per year, which represents a nearly 70 percent reduction in salt loading to the river.
Galaxy Zoo: evidence for diverse star formation histories through the green valley
NASA Astrophysics Data System (ADS)
Smethurst, R. J.; Lintott, C. J.; Simmons, B. D.; Schawinski, K.; Marshall, P. J.; Bamford, S.; Fortson, L.; Kaviraj, S.; Masters, K. L.; Melvin, T.; Nichol, R. C.; Skibba, R. A.; Willett, K. W.
2015-06-01
Does galaxy evolution proceed through the green valley via multiple pathways or as a single population? Motivated by recent results highlighting radically different evolutionary pathways between early- and late-type galaxies, we present results from a simple Bayesian approach to this problem wherein we model the star formation history (SFH) of a galaxy with two parameters, [t, τ] and compare the predicted and observed optical and near-ultraviolet colours. We use a novel method to investigate the morphological differences between the most probable SFHs for both disc-like and smooth-like populations of galaxies, by using a sample of 126 316 galaxies (0.01 < z < 0.25) with probabilistic estimates of morphology from Galaxy Zoo. We find a clear difference between the quenching time-scales preferred by smooth- and disc-like galaxies, with three possible routes through the green valley dominated by smooth- (rapid time-scales, attributed to major mergers), intermediate- (intermediate time-scales, attributed to minor mergers and galaxy interactions) and disc-like (slow time-scales, attributed to secular evolution) galaxies. We hypothesize that morphological changes occur in systems which have undergone quenching with an exponential time-scale τ < 1.5 Gyr, in order for the evolution of galaxies in the green valley to match the ratio of smooth to disc galaxies observed in the red sequence. These rapid time-scales are instrumental in the formation of the red sequence at earlier times; however, we find that galaxies currently passing through the green valley typically do so at intermediate time-scales.†
Pries, Alissa M; Huffman, Sandra L; Champeny, Mary; Adhikary, Indu; Benjamin, Margaret; Coly, Aminata Ndeye; Diop, El Hadji Issakha; Mengkheang, Khin; Sy, Ndèye Yaga; Dhungel, Shrid; Feeley, Alison; Vitta, Bineti; Zehner, Elizabeth
2017-10-01
The availability and consumption of commercially produced foods and beverages have increased across low-income and middle-income countries. This cross-sectional survey assessed consumption of commercially produced foods and beverages among children 6-23 months of age, and mothers' exposure to promotions for these products. Health facility-based interviews were conducted among 218 randomly sampled mothers utilizing child health services in Dakar, Senegal; 229 in Dar es Salaam, Tanzania; 228 in Kathmandu Valley, Nepal; and 222 in Phnom Penh, Cambodia. In the day prior to the interview, 58.7% of 6-23-month-olds in Dakar, 23.1% in Dar es Salaam, 74.1% in Kathmandu Valley, and 55.0% in Phnom Penh had consumed a commercially produced snack food. In the previous week, the majority of children in Dakar (79.8%), Kathmandu Valley (91.2%), and Phnom Penh (80.6%) had consumed such products. Consumption of commercially produced sugar-sweetened beverages was noted among 32.0% of Phnom Penh, 29.8% of Dakar, 23.1% of Dar es Salaam, and 16.2% of Kathmandu Valley children. Maternal education was negatively associated with commercial snack food consumption in Dakar and Kathmandu Valley. Children of Phnom Penh mothers in the lowest wealth tercile were 1.5 times more likely to consume commercial snack food products, compared to wealthier mothers. These snack consumption patterns during the critical complementary feeding period demand attention; such products are often high in added sugars and salt, making them inappropriate for infants and young children. © 2017 John Wiley & Sons Ltd.
Evaporation from irrigated crops: Its measurement, modeling and estimation from remotely sensed data
NASA Astrophysics Data System (ADS)
Garatuza-Payan, Jaime
The research described in this dissertation is predicated on the hypothesis that remotely sensed information from climatological satellites can be used to estimate the actual evapotranspiration from agricultural crops to improve irrigation scheduling and water use efficiency. The goal of the enabling research program described here was to facilitate and demonstrate the potential use of satellite data for the rapid and routine estimation of water use by irrigated crops in the Yaqui Valley irrigation scheme, an extensive irrigated area in Sonora, Mexico. The approach taken was first, to measure and model the evapotranspiration and crop factors for wheat and cotton, the most common irrigated crops in the Yaqui Valley scheme. Second, to develop and test a high-resolution (4 km x 4 km) method for determining cloud cover and solar radiation from GOES satellite data. Then third, to demonstrate the application of satellite data to calculate the actual evaporation for sample crops in the Yaqui Valley scheme by combining estimates of potential rate with relevant crop factors and information on crop management. Results show that it is feasible to provide routine estimates of evaporation for the most common crops in the Yaqui Valley irrigation scheme from satellite data. Accordingly, a system to provide such estimates has been established and the Water Users Association, the entity responsible for water distribution in Yaqui Valley, can now use them to decide whether specific fields need irrigation. A Web site (teka-pucem.itson.mx) is also being created which will allow individual farmers to have direct access to the evaporation estimates via the Internet.
Multi-scale curvature for automated identification of glaciated mountain landscapes☆
Prasicek, Günther; Otto, Jan-Christoph; Montgomery, David R.; Schrott, Lothar
2014-01-01
Erosion by glacial and fluvial processes shapes mountain landscapes in a long-recognized and characteristic way. Upland valleys incised by fluvial processes typically have a V-shaped cross-section with uniform and moderately steep slopes, whereas glacial valleys tend to have a U-shaped profile with a changing slope gradient. We present a novel regional approach to automatically differentiate between fluvial and glacial mountain landscapes based on the relation of multi-scale curvature and drainage area. Sample catchments are delineated and multiple moving window sizes are used to calculate per-cell curvature over a variety of scales ranging from the vicinity of the flow path at the valley bottom to catchment sections fully including valley sides. Single-scale curvature can take similar values for glaciated and non-glaciated catchments but a comparison of multi-scale curvature leads to different results according to the typical cross-sectional shapes. To adapt these differences for automated classification of mountain landscapes into areas with V- and U-shaped valleys, curvature values are correlated with drainage area and a new and simple morphometric parameter, the Difference of Minimum Curvature (DMC), is developed. At three study sites in the western United States the DMC thresholds determined from catchment analysis are used to automatically identify 5 × 5 km quadrats of glaciated and non-glaciated landscapes and the distinctions are validated by field-based geological and geomorphological maps. Our results demonstrate that DMC is a good predictor of glacial imprint, allowing automated delineation of glacially and fluvially incised mountain landscapes. PMID:24748703