Science.gov

Sample records for east mesa site

  1. Field tests of 2- and 40-tube condensers at the East Mesa Geothermal Test Site

    SciTech Connect

    Murphy, R.W.; Domingo, N.

    1982-05-01

    Two water-cooled isobutane condensers, one with 2 tubes and one with 40 tubes, were subjected to field tests at the East Mesa Geothermal Test Site to assess relative heat transfer performance in both surface evaporator and direct-contact evaporator modes. The five groups of tests established that field performance was below earlier laboratory-determined levels and that direct-contact evaporator mode performance was poorer than that for the surface evaporator mode. In all test situations, fluted condenser tubes performed better than smooth condenser tubes. Cooling water quality had no significant effect on performance, but brine preflash in the direct-contact mode did promote some relative performance improvement. Important implications of these results for binary geothermal power plants are that (1) working-fluid-side impurities can significantly degrade heat transfer performance of the power plant condensers and (2) provisions for minimizing such impurities may be required.

  2. 'Bread Loaf' Mesa East of Phlegra Montes

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    An isolated mesa east of the Phlegra Montes in northeastern Elysium Planitia has a cracked surface that, combined with its overall shape, gives the appearance of a giant loaf of bread. Other mesas with similar surfaces are found in the area, suggesting that at one time these mesas were part of a continuous layer of material. It is likely that at that time, some process caused the graben-like cracks to form. Later erosion of the cracked layer left only the isolated mesas seen in the THEMIS image. One clue that supports this scenario is the presence of many filled and eroded craters throughout the scene but no fresh ones. One way to produce this landscape begins with an ancient and heavily cratered surface that subsequently is buried by some other material. If this overburden was stripped off relatively recently, not enough time would have passed to allow for a new population of fresh craters to be produced. The result would be a landscape with isolated mesas of younger material on top of an ancient, cratered surface.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Foundation ruins atop La Bajada Mesa, just east of the ...

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

    Foundation ruins atop La Bajada Mesa, just east of the crest. Possibly a rest stop during the NM 1/National Old Trails Road period (1909-26). View east. - La Bajada Historic Trails and Roads, Approximately 1 mile East/Northeast of intersection of State Highway 16 and Indian Service Road 841, La Bajada, Santa Fe County, NM

  4. FRACSL CODE DEVELOPMENT AND CORRELATION OF EAST MESA TEST RESULTS

    SciTech Connect

    Clemo, T.M.

    1985-01-22

    The FRACSL flow and transport code is under development as part of an effort to improve reservoir characterization techniques. The present version simulates a two-dimensional, isothermal reservoir composed of a global fracture network imbedded in a porous media. FRACSL simulates the hydraulic response of a reservoir to injection or backflow. The code simulates the movement of injected tracers within the reservoir by adding advective and random dispersive motions of discrete particles. FRACSL has been benchmarked against theoretical flow and transport responses in simple systems. It has been used to simulate a benchscale physical model and to correlate flow and dispersion data from the East Mesa Hydrothermal Injection Test Program. Correlation of East Mesa data has provided an estimate of an anisotropic hydraulic conductivity, a natural drift in the reservoir, and dispersivity.

  5. Session 2: Review of the 500 KW Direct Contact Geothermal Plant at East Mesa

    SciTech Connect

    Nichols, Kenneth E.

    1983-12-01

    The concept of a binary power cycle utilizing direct contact heat exchangers was first proposed by Jacobs and Boehm in 1973 for use with geothermal brines. This concept was proposed primarily to overcome difficulties associated with the fouling and scaling nature of many moderate temperature brines. However, thermodynamic analyses and subsequent economic analyses clearly pointed to possible economic advantages over conventional binary cycles even with non-fouling, non-scaling brines. For a direct contact binary power plant to be economically attractive it is necessary that a small pinch point be obtainable so that a maximum amount of power can be obtained per unit mass flow of geothermal brine. Since the working fluid comes in direct contact with the brine it must be immiscible with the brine, low in cost and, if part of it goes into solution in the brine, easily recoverable. In addition, noncondensible gases from the brine must be controlled to limit their effect on condenser pressure. The 500 kWe DCHX test facility installed at East Mesa was designed to evaluate techniques to provide economical operation. The choice of the East Mesa test site as a first location to evaluate the DCHX system placed additional requirements on the system. The brine at East Mesa was at low pressure, requiring the use of downhole pumps. The selection of isobutane as a working fluid required increasing the pressure of the brine. The high amount of dissolved CO{sub 2} in the brine required that it be preflashed to prevent the carryover of CO{sub 2} gas through the turbine and into the condenser which would adversely affect the system performance. All of these problems have been met by the system designer and operator, Barber-Nichols Engineering. Further, problems with isobutane turbine design, supposed state-of-the-art, were encountered and resolved.

  6. Geothermal fluids to irrigate energy crops on Imperial East Mesa Desert, California

    SciTech Connect

    Robinson, F.E.; Thomas, T.R.; Singh, K.

    1981-10-01

    Geothermal fluid at 2200 parts per million(ppM) total dissolved solids from the East Mesa, California was compared to 1400 ppM ground water from a 100 m well as irrigation sources for Beta vulgaris (L.) USH-11 sugar beet and Tamarix aphylla (L.) athel, a biomass and windbreak tree. In 1980 there was no significant difference between the yields from the two waters. In 1981, there was no significant difference between biomass production from the waters on the athel. The geothermal water produced a larger yield of sucrose than the ground water. The data suggest that raising sugar beets with either water is feasible on the East Mesa.

  7. Recent Changes in Ground Deformation at the East Mesa Geothermal Field, California as Measured by InSAR

    NASA Astrophysics Data System (ADS)

    Taylor, H.; Pritchard, M. E.; Lohman, R. B.

    2013-12-01

    The East Mesa Geothermal Field in East Mesa, Imperial County, California is a series of 6 geothermal power plants with a 57MW capacity that has been in operation since 1987. Previous InSAR studies using ERS-1 and ERS-2 data (1992-2001) have observed ongoing subsidence at rates between -32 to -43 mm/yr. The observed subsidence at this site was thought to be caused by reservoir compaction since there was a negative net production of water during that time period. However, even though net production remained negative, more recent Envisat data reveal a shift in the subsidence signal towards the north and onset of relative uplift in the south portion of the geothermal field starting in 2006. We examine three datasets over East Mesa, including 57 descending ERS-1 and ERS-2 SAR images as well as 35 ascending and 48 descending Envisat SAR acquisitions, to create more than 900 interferograms over the 18 year time period (1992-2010). This dense temporal coverage is valuable for evaluating variations in deformation patterns and minimizing the contribution from the atmosphere. A modified version of the small baseline subset (SBAS) method is used to generate time series of ground displacements and average velocities. ERS data are consistent with previous studies showing rates between -30 and -40 mm/year in the line-of-sight while the Envisat time series' show line-of-sight rates of -20 mm/yr and 12 mm/yr for maximum subsidence and uplift. Net production at the East Mesa Geothermal Field is calculated using production and injection data provided by the California Department of Conservation. The average net production is estimated as -383,000 metric tons per month over the time span of Envisat data and remained negative even during the onset of relative uplift.

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

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.

    2009-01-01

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

  9. Deep Resistivity Structure of Rainier Mesa-Shoshone Mountain, Nevada Test Site, Nevada

    SciTech Connect

    Theodore H. Asch; Brian D. Rodriguez; Jay A. Sampson; Jackie M. Williams; Maryla Deszcz-Pan

    2006-12-12

    The U. S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing groundwater contamination resulting from historical underground nuclear testing through the Environmental Management (EM) program and, in particular, the Underground Test Area (UGTA) project. During 2005, the U.S. Geological Survey (USGS), funded by the DOE and NNSA-NSO, collected and processed data from twenty-six Magnetotelluric (MT) and Audio-Magnetotelluric (AMT) sites at the Nevada Test Site. Data stations were located in and near Rainier Mesa and Shoshone Mountain to assist in characterizing the pre-Tertiary geology in those areas. These new stations extend to the west the hydrogeologic study that was conducted in Yucca Flat in 2003. This work has helped to refine the character, thickness, and lateral extent of pre Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU – late Devonian to Mississippian-age siliciclastic rocks assigned to the Eleana Formation and Chainman Shale(Bechtel Nevada, 2006)) in the Yucca Flat area and west towards Shoshone Mountain in the south, east of Buckboard Mesa, and onto Rainier Mesa in the north. The Nevada Test Site magnetotelluric data interpretation presented in this report includes the results of detailed two-dimensional (2 D) resistivity modeling for each profile (including alternative interpretations) and gross inferences on the three dimensional (3 D) character of the geology within the region. The character, thickness, and lateral extent of the Chainman Shale and Eleana Formation that comprise the Upper Clastic Confining Unit (UCCU) are generally characterized in the upper 5 km. The interpretation is not well determined where conductive TCU overlies conductive Chainman Shale, where resistive Eleana Formation overlies resistive LCA units, or where resistive VTA rock overlies units of the Eleana Formation. The nature of the volcanic units in the west has been refined as are large and small fault structures such as the CP Thrust Fault, the Carpetbag Fault, and the Yucca Fault that cross Yucca Flat. The subsurface electrical resistivity distribution and inferred geologic structures determined by this investigation should help constrain the hydrostratigraphic framework model that is under development for the Rainier Mesa/Shoshone Mountain Corrective Action Unit and areas to the west and in understanding the effects on ground-water flow in the area.

  10. A PLAUSIBLE TWO-DIMENSIONAL VERTICAL MODEL OF THE EAST MESA GEOTHERMAL FIELD, CALIFORNIA, U.S.A

    SciTech Connect

    Goyal, K.P.; Kassoy, D.R.

    1980-03-01

    A two-dimensional conceptual model of the East Mesa geothermal system is developed on the basis of the existing geological, geophysical geochemical, heat flux, and borehole logging data. A fault called the Mesa Fault is assumed to charge the reservoir, which is overlaid by a clay-rich cap. The mathematical model :is based on the flow of liquid water in a saturated porous medium. To obtain temperature-depth distributions similar to those measured at the site, we assume that the liquid is convecting at a high Rayleigh number. In this approximation, liquid rises up the fault and spreads into the near regions of the reservoir isothermally. The cooling effect of the surface on the flow in the reservoir is confined to a thin layer adjacent to the cap-reservoir interface near the fault. This layer grows with the distance from the fault. Eventually, the full depth of the reservoir is cooled by the surface. Results are obtained for the velocities, pressures, and temperatures of the entire system (fault zone, aquifer and clay cap). Finally we compare the heat flux predicted for the surface to that measured at the site in shallow wells.

  11. An Isotopic Investigation of Groundwater Recharge in the East Mesa Area of the Salton Sea Basin

    NASA Astrophysics Data System (ADS)

    Moran, J. E.; Tompson, A. F.; Demir, Z.

    2008-12-01

    The Salton Sea Basin, a closed topographic basin located in arid southeastern California and a portion of Baja California, Mexico, is home to some of the most productive agricultural lands in the United States. In the Imperial Valley, in the southern portion of the basin, groundwater use is limited owing to the wide availability of imported water, low urban demand, and water production and quality limitations. Intense interest in developing new water supplies and, separately, restoring the Salton Sea has led to renewed interest in the availability of groundwater in the Imperial Valley, especially the East Mesa area, where decades of leakage from unlined canals has likely impacted groundwater. This study uses isotopic tracers of the water molecule to examine the source of water and groundwater residence time in the East Mesa area between the All American and Coachella canals and the Salton Sea. Groundwater samples were collected from 12 wells and from the All American Canal at Drop 1 for stable isotopes of the water molecule and for tritium-helium groundwater age. Remote well locations, unfavorable well construction, and a dearth of monitoring wells with small open intervals, however, placed limitations on both sample integrity and on spatial coverage of the sampling area. The aridity of the Salton Sea area, and the long history of irrigation with Colorado River water, has marked the groundwater with an evaporated Colorado River water stable isotope signature. High tritium waters (captured in the extensive surface storage system of the Colorado River during peak fallout) that have infiltrated in the Salton Sea area make another good tracer of groundwater transport. Recently recharged groundwater, with tritium-helium apparent ages of less than 2 years, has a chemical and isotopic signature that closely matches water from the canal, and is found in wells directly adjacent to the All American canal. Mean apparent ages of 10 to 40 years were observed in wells at distances of 1 km to more than 7 km from the canal. These wells have isotopic signatures of less evaporated Colorado River water, indicating recharge took place after emplacement of at least some of the dams but during a time of high tritium fallout from atmospheric weapons testing. Overall, the results suggest that there has been significant leakage from the unlined canals, and that water penetrates to much greater depth in the East Mesa study area when compared to the Central Imperial Valley where irrigated agriculture dominates the landscape. These are consistent with other interpretations based upon purely geologic and water budget considerations.

  12. Nature and extent of lava-flow aquifers beneath Pahute Mesa, Nevada Test Site

    SciTech Connect

    Prothro, L.B.; Drellack, S.L. Jr.

    1997-09-01

    Work is currently underway within the Underground Test Area subproject of the US Department of Energy/Nevada Operations Office Environmental Restoration Program to develop corrective action plans in support of the overall corrective action strategy for the Nevada Test Site as established in the Federal Facility Agreement and Consent Order (FFACO, 1996). A closure plan is currently being developed for Pahute Mesa, which has been identified in the FFACO as consisting of the Western and Central Pahute Mesa Corrective Action Units. Part of this effort requires that hydrogeologic data be compiled for inclusion in a regional model that will be used to predict a contaminant boundary for these Corrective Action Units. Hydrogeologic maps have been prepared for use in the model to define the nature and extent of aquifers and confining units that might influence the flow of contaminated groundwater from underground nuclear tests conducted at Pahute Mesa. Much of the groundwater flow beneath Pahute Mesa occurs within lava-flow aquifers. An understanding of the distribution and hydraulic character of these important hydrogeologic units is necessary to accurately model groundwater flow beneath Pahute Mesa. This report summarizes the results of a study by Bechtel Nevada geologists to better define the hydrogeology of lava-flow aquifers at Pahute Mesa. The purpose of this study was twofold: (1) aid in the development of the hydrostratigraphic framework for Pahute Mesa, and (2) provide information on the distribution and hydraulic character of lava-flow aquifers beneath Pahute Mesa for more accurate computer modeling of the Western and Central Pahute Mesa Corrective Action Units.

  13. Failure analysis report: Heat exchanger tubes geothermal binary power plant, Magma Electric Company, East Mesa, California

    SciTech Connect

    Anliker, Dennis M.; Ellis, Peter F. II

    1982-05-01

    Radian received twelve sections of heat exchanger tubing from the Magma Electric Company's 10MW(e) East Mesa binary geothermal power plant. Three tube sections were received from each of four shell and tube heat exchangers (HX1, Hx6, HX8, and Hx10) of the isobutane vaporizer train. All samples were taken from the upper few rows of tubes. Two months later, four more tube sections were received. These four sections were taken from the lower rows of heat exchangers 1, 6 (two sections), and 10. Radian was requested to investigate the cause of severe pitting failure of these heat exchanger tubes. This report is part of a continuing DOE effort to gain insight into the service life of component materials employed in geothermal energy utilization.

  14. Hydrogeologic investigations of flow in fractured tuffs, Rainier Mesa, Nevada Test Site

    NASA Astrophysics Data System (ADS)

    Russell, Charles E.; Hess, John W.; Tyler, Scott W.

    Rainier Mesa, a primary site for nuclear testing, is located in the north central area of the Nevada Test Site, and is composed of highly fractured and altered Tertiary tuffs. A hydrogeologic study was conducted within the mesa concentrating on several parameters: the source of ground water found in Rainier Mesa, period of principal recharge, ground-water travel time between the mesa surface and the tunnel level, period of hydraulic response, and total amount of recharge per year to U12n Tunnel recharge basin. The data base consists of: the precipitation record, discharge record of seeps within Rainier Mesa, the gross chemistry and stable isotopic composition of these seeps, and two tracer studies conducted from the mesa surface. Results indicate that ground water is of recent meteoric origin, winter is the period of principal recharge, the period of hydrologic response is at least four months, the total recharge is approximately eight percent of the precipitation which falls on the U12n recharge basin, and travel time is estimated as greater than one year and less than six. These observations describe an environment which has been subjected to nuclear testing since 1957. It is certain that this testing has altered the hydrogeochemical environment and it is suspected that some alteration of the hydraulic system has also occurred.

  15. NTS (Nevada Test Site) Mesa recharge study FY 1988: Letter report

    SciTech Connect

    Lyles, B F; Mihevc, T M

    1990-03-01

    Pahute Mesa is a large geomorphic feature that is located in Areas 19 and 20 of the Nevada Test Site (NTS) and a portion of the Nellis Air Force Range. The identification of radionuclide migration at the U20n site has resulted in an increased interest in the hydrology of Pahute Mesa. An important aspect of groundwater studies is to estimate groundwater recharge from precipitation. Although some meteorological data have been collected on Pahute Mesa, they are not sufficient for making these recharge estimates. The elevation of Pahute Mesa that lies within the boundaries of the NTS ranges from under 6000 ft to over 7000 ft. Accompanying these elevation changes is a variety of plant communities. Vegetation in areas of low elevation is dominated by sagebrush and by pinyon/juniper at the higher elevations. Communities of Gambel oak are interspersed with pinyon/juniper. Varying plant communities on Pahute Mesa are indicative of the nonuniformity of precipitation and soil types. To understand the mechanisms that lead to recharge, it is necessary to know the spatial as well as temporal variation in precipitation. At the same time, the conditions in the soil need to be monitored to determine if the precipitation is, in fact, infiltrating to the critical depth needed to attain groundwater recharge.

  16. NTS (Nevada Test Site) Mesa recharge study FY 1989: Letter report

    SciTech Connect

    Lyles, B F; Mihevc, T M

    1990-03-01

    Pahute Mesa is a large geomorphic feature that is located in Areas 19 and 20 of the Nevada Test Site (NTS) and a portion of the Nellis Air Force Range. The identification of radionuclide migration at the U20n site has resulted in an increased interest in the hydrology of Pahute Mesa. An important aspect of groundwater studies is to estimate groundwater recharge from precipitation. Although some meteorological data have been collected on Pahute Mesa, they are not sufficient for making these recharge estimates. The elevation of Pahute Mesa that lies within the boundaries of the NTS ranges from under 6,000 feet to over 7,000 feet. Accompanying these elevation changes is a variety of plant communities. Vegetation in areas of low elevation is dominated by sagebrush and pinyon/juniper at the higher elevation. Communities of Gambel oak are interspersed with pinyon/juniper. Varying plant communities on Pahute Mesa are indicative of the nonuniformity of precipitation and soil types. To understand the mechanisms that lead to recharge, it is necessary to know the spatial as well as temporal variation in precipitation. At the same time, the conditions in the soil need to be monitored to determine if the precipitation is, in fact, infiltrating to the critical depth needed to attain groundwater recharge. These areas of study are covered in this report. 8 figs., 4 tabs.

  17. COMBINED LEPA AND MESA IRRIGATION ON A SITE SPECIFIC LINEAR MOVE SYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An off-the-shelf PLC-based control system has been developed and field tested to enable site-specific irrigation of multiple 50 ft X 80 ft research plots using either mid-elevation spray heads (MESA) and low energy precision application (LEPA) irrigation methods on linear move sprinkler systems. Bo...

  18. Internal Technical Report, Hydrothermal Injection Program - East Mesa 1983-84 Test Data

    SciTech Connect

    Freiburger, R.M.

    1984-09-01

    This report presents a test data index and a data plots for a series of 12 drawdown and tracer injection-withdrawal tests in porous-media aquifers at the East Mesa Geothermal Field located in the Imperial Valley near El Centro, California. Test and instrumentation summaries are also provided. The first 10 of these tests were completed during July and August 1983. The remaining 2 tests were completed in February 1984, after a 6-month quiescent period, in which tracers were left in the reservoir. The test wells used were 56-30 and 56-19, with 38-30 supplying water for the injection phase and 52-29 used as a disposal well during the backflowing of the test wells. Six other wells in the surrounding area were measured periodically for possible hydrologic effects during testing. It is not the intent of this report to supply analyzed data, but to list the uninterpreted computer stored data available for analysis. The data have been examined only to the extent to ensure that they are reasonable and internally consistent. This data is stored on permanent files at the Idaho National Engineering Laboratory (INEL) Cyber Computer Complex. The main processors for this complex are located at the Computer Science Center (CSC) in Idaho Falls, Idaho. The Hydrothermal Injection Test program, funded by the Department of Energy, was a joint effort between EG and G Idaho, Inc., the University of Utah Research Institute (UURI) and Republic Geothermal, Inc. (RGI) of Santa Fe Springs, California.

  19. 5. VIEW SHOWING HORSE MESA DAM UNDER CONSTRUCTION. THREE PENSTOCKS ...

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

    5. VIEW SHOWING HORSE MESA DAM UNDER CONSTRUCTION. THREE PENSTOCKS ARE AT CENTER AND CONCRETE TOWER LINES. AGGREGATE OPERATION IS VISIBLE ABOVE CONSTRUCTION SITE July 22, 1926 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  20. Mesa = Table

    NASA Technical Reports Server (NTRS)

    2006-01-01

    10 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two mesas on the northern plains of Mars. 'Mesa' is the Spanish word for 'table,' and that is a very good description of the two elliptical features captured in this MOC image. In both cases, the mesa tops and the material beneath them, down to the level of the surrounding, rugged plain, are remnants of a once more extensive layer (or layers) of material that has been largely eroded away. The circular feature near the center of the larger mesa is the site of a filled and buried impact crater.

    Location near: 53.5oN, 153.5oW Image width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Spring

  1. Magnetotelluric Data, Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nevada.

    SciTech Connect

    Jackie M. Williams; Jay A. Sampson; Brian D. Rodriguez; and Theodore H. Asch.

    2006-11-03

    The United States Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing ground-water contamination resulting from historical underground nuclear testing through the Environmental Management (EM) program and, in particular, the Underground Test Area (UGTA) project. From 1951 to 1992, 828 underground nuclear tests were conducted at the Nevada Test Site northwest of Las Vegas. Most of these tests were conducted hundreds of feet above the ground-water table; however, more than 200 of the tests were near or within the water table. This underground testing was limited to specific areas of the Nevada Test Site, including Pahute Mesa, Rainier Mesa/Shoshone Mountain, Frenchman Flat, and Yucca Flat. One issue of concern is the nature of the somewhat poorly constrained pre-Tertiary geology, and its effects on ground-water flow. Ground-water modelers would like to know more about the hydrostratigraphy and geologic structure to support a hydrostratigraphic framework model that is under development for the Rainier Mesa/Shoshone Mountain Corrective Action Unit (Bechtel Nevada, 2006). During 2005, the U.S. Geological Survey (USGS), in cooperation with the DOE and NNSA-NSO, collected and processed data from twenty-six magnetotelluric (MT) and audio-magnetotelluric (AMT) sites at the Nevada Test Site. The 2005 data stations were located on and near Rainier Mesa and Shoshone Mountain to assist in characterizing the pre-Tertiary geology in those areas. These new stations extend the area of the hydrogeologic study previously conducted in Yucca Flat. This work will help refine what is known about the character, thickness, and lateral extent of pre-Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU – late Devonian to Mississippian-age siliciclastic rocks assigned to the Eleana Formation and Chainman Shale) from the Yucca Flat area and west towards Shoshone Mountain, to Buckboard Mesa in the south, and onto Rainier Mesa in the north. Subsequent interpretation will include a three-dimensional (3-D) character analysis and a two-dimensional (2-D) resistivity model. The purpose of this report is to release the MT sounding data for the twenty-six stations shown in figure 1. No interpretation of the data is included here.

  2. Geology, hydrothermal petrology, stable isotope geochemistry, and fluid inclusion geothermometry of LASL geothermal test well C/T-1 (Mesa 31-1), East Mesa, Imperial Valley, California, USA

    SciTech Connect

    Miller, K.R.; Elders, W.A.

    1980-08-01

    Borehole Mesa 31-1 (LASL C/T-1) is an 1899-m (6231-ft) deep well located in the northwestern part of the East Mesa Geothermal Field. Mesa 31-1 is the first Calibration/Test Well (C/T-1) in the Los Alamos Scientific Laboratory (LASL), Geothermal Log Interpretation Program. The purpose of this study is to provide a compilation of drillhole data, drill cuttings, well lithology, and formation petrology that will serve to support the use of well LASL C/T-1 as a calibration/test well for geothermal logging. In addition, reviews of fluid chemistry, stable isotope studies, isotopic and fluid inclusion geothermometry, and the temperature log data are presented. This study provides the basic data on the geology and hydrothermal alteration of the rocks in LASL C/T-1 as background for the interpretation of wireline logs.

  3. Integrated model of the shallow and deep hydrothermal systems in the East Mesa area, Imperial Valley, California

    SciTech Connect

    Riney, T.D.; Pritchett, J.W.; Rice, L.F.

    1982-01-01

    Geological, geophysical, thermal, petrophysical and hydrological data available for the East Mesa hydrothermal system that are pertinent to the construction of a computer model of the natural flow of heat and fluid mass within the system are assembled and correlated. A conceptual model of the full system is developed and a subregion selected for quantitative modeling. By invoking the Boussinesq approximation, valid for describing the natural flow of heat and mass in a liquid hydrothermal system, it is found practical to carry computer simulations far enough in time to ensure that steady-state conditions are obtained. Initial calculations for an axisymmetric model approximating the system demonstrate that the vertical formation permeability of the deep East Mesa system must be very low (k/sub v/ approx. 0.25 to 0.5 md). Since subsurface temperature and surface heat flow data exhibit major deviations from the axisymmetric approximation, exploratory three-dimensional calculations are performed to assess the effects of various mechanisms which might operate to produce such observed asymmetries. A three-dimensional model evolves from this iterative data synthesis and computer analysis which includes a hot fluid convective source distributed along a leaky fault radiating northward from the center of the hot spot and realistic variations in the reservoir formation properties.

  4. Integrated model of the shallow and deep hydrothermal systems in the East Mesa area, Imperial Valley, California

    USGS Publications Warehouse

    Riney, T. David; Pritchett, J.W.; Rice, L.F.

    1982-01-01

    Geological, geophysical, thermal, petrophysical and hydrological data available for the East Mesa hydrothermal system that are pertinent to the construction of a computer model of the natural flow of heat and fluid mass within the system are assembled and correlated. A conceptual model of the full system is developed and a subregion selected for quantitative modeling. By invoking the .Boussinesq approximation, valid for describing the natural flow of heat and mass in a liquid hydrothermal system, it is found practical to carry computer simulations far enough in time to ensure that steady-state conditions are obtained. Initial calculations for an axisymmetric model approximating the system demonstrate that the vertical formation permeability of the deep East Mesa system must be very low (kv ~ 0.25 to 0.5 md). Since subsurface temperature and surface heat flow data exhibit major deviations from the axisymmetric approximation, exploratory three-dimensional calculations are performed to assess the effects of various mechanisms which might operate to produce such observed asymmetries. A three-dimensional model evolves from this iterative data synthesis and computer analysis which includes a hot fluid convective source distributed along a leaky fault radiating northward from the center of the hot spot and realistic variations in the reservoir formation properties.

  5. Quantifying Hydraulic Properties and Connections Between Structural Blocks at Pahute Mesa, Nevada National Security Site

    NASA Astrophysics Data System (ADS)

    Jackson, T. R.; Halford, K. J.; Garcia, C. A.

    2014-12-01

    Underground testing of high-yield nuclear devices on eastern Pahute Mesa in the Nevada National Security Site during the period from 1965-92 has introduced radionuclides into the groundwater system. Groundwater flow is complex because Pahute Mesa is underlain by a thick sequence of alternating lava flows and tuffs which have been faulted into distinct structural blocks. Hydraulic properties of volcanic-rock aquifers, confining units, and fault structures have been quantified across a 50 mi² area where radionuclide transport occurs. This large area has been investigated by pumping 60 million gallons of groundwater during 16 large-scale aquifer tests. Water-level changes have been detected in observation wells more than 3 mi from pumped wells and were interpreted simultaneously with multiple groundwater flow models—one model for each well site. Hydraulic properties were distributed with a single hydrogeologic framework model that was sampled by each groundwater-flow model. Hydraulic properties were estimated across structural blocks with offsets of 1,500 ft where pumping signals were measured across fault structures. The resulting large-scale estimates of hydraulic conductivity distributions and regional transmissivity map will improve predictions of radionuclide transport.

  6. Actinide Sorption in Rainier Mesa Tunnel Waters from the Nevada Test Site

    SciTech Connect

    Zhao, P; Zavarin, M; Leif, R; Powell, B; Singleton, M; Lindvall, R; Kersting, A

    2007-12-17

    The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. The sorption K{sub d} for Am(III) and Pu(IV) on volcanic zeolitized tuff was up to two orders of magnitude lower in samples with high DOM (15 to 19 mg C/L) compared to samples with DOM removed (< 0.4 mg C/L) or samples with naturally low DOM (0.2 mg C/L). In contrast, Np(V) and U(VI) sorption to zeolitized tuff was much less affected by the presence of DOM. The Np(V) and U(VI) sorption Kds were low under all conditions. Importantly, the DOM was not found to significantly sorb to the zeolitized tuff during these experiment. The concentration of DOM in groundwater affects the transport behavior of actinides in the subsurface. The mobility of Am(III) and Pu(IV) is significantly higher in groundwater with elevated levels of DOM resulting in potentially enhanced transport. To accurately model the transport behavior of actinides in groundwater at Rainier Mesa, the low actinide Kd values measured in groundwater with high DOM concentrations must be incorporated in predictive transport models.

  7. Geologic Surface Effects of Underground Nuclear Testing, Buckboard Mesa, Climax Stock, Dome Mountain, Frenchman Flat, Rainier/Aqueduct Mesa, and Shoshone Mountain, Nevada Test Site, Nevada

    USGS Publications Warehouse

    Grasso, Dennis N.

    2003-01-01

    Surface effects maps were produced for 72 of 89 underground detonations conducted at the Frenchman Flat, Rainier Mesa and Aqueduct Mesa, Climax Stock, Shoshone Mountain, Buckboard Mesa, and Dome Mountain testing areas of the Nevada Test Site between August 10, 1957 (Saturn detonation, Area 12) and September 18, 1992 (Hunters Trophy detonation, Area 12). The ?Other Areas? Surface Effects Map Database, which was used to construct the maps shown in this report, contains digital reproductions of these original maps. The database is provided in both ArcGIS (v. 8.2) geodatabase format and ArcView (v. 3.2) shapefile format. This database contains sinks, cracks, faults, and other surface effects having a combined (cumulative) length of 136.38 km (84.74 mi). In GIS digital format, the user can view all surface effects maps simultaneously, select and view the surface effects of one or more sites of interest, or view specific surface effects by area or site. Three map layers comprise the database. They are: (1) the surface effects maps layer (oase_n27f), (2) the bar symbols layer (oase_bar_n27f), and (3) the ball symbols layer (oase_ball_n27f). Additionally, an annotation layer, named 'Ball_and_Bar_Labels,' and a polygon features layer, named 'Area12_features_poly_n27f,' are contained in the geodatabase version of the database. The annotation layer automatically labels all 295 ball-and-bar symbols shown on these maps. The polygon features layer displays areas of ground disturbances, such as rock spall and disturbed ground caused by the detonations. Shapefile versions of the polygon features layer in Nevada State Plane and Universal Transverse Mercator projections, named 'area12_features_poly_n27f.shp' and 'area12_features_poly_u83m.shp,' are also provided in the archive.

  8. Development of Combined Site-Specific MESA and LEPA Methods on a Linear Move Sprinkler Irrigation System

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A site-specific controller, hardware and software systems were developed with the capability to switch between either mid-elevation spray application (MESA) or low energy precision application (LEPA) methods. These systems were field tested and used to manage site-specific irrigations under a linear...

  9. Hydraulic Property and Soil Textural Classification Measurements for Rainier Mesa, Nevada Test Site, Nevada

    SciTech Connect

    Ebel, Brian A.; Nimmo, John R.

    2009-12-29

    This report presents particle size analysis, field-saturated hydraulic conductivity measurements, and qualitative descriptions of surficial materials at selected locations at Rainier Mesa, Nevada. Measurements and sample collection were conducted in the Rainier Mesa area, including unconsolidated sediments on top of the mesa, an ephemeral wash channel near the mesa edge, and dry U12n tunnel pond sediments below the mesa. Particle size analysis used a combination of sieving and optical diffraction techniques. Field-saturated hydraulic conductivity measurements employed a single-ring infiltrometer with analytical formulas that correct for falling head and spreading outside the ring domain. These measurements may prove useful to current and future efforts at Rainier Mesa aimed at understanding infiltration and its effect on water fluxes and radionuclide transport in the unsaturated zone.

  10. Hydraulic Property and Soil Textural Classification Measurements for Rainier Mesa, Nevada Test Site, Nevada

    USGS Publications Warehouse

    Ebel, Brian A.; Nimmo, John R.

    2010-01-01

    This report presents particle size analysis, field-saturated hydraulic conductivity measurements, and qualitative descriptions of surficial materials at selected locations at Rainier Mesa, Nevada. Measurements and sample collection were conducted in the Rainier Mesa area, including unconsolidated sediments on top of the mesa, an ephemeral wash channel near the mesa edge, and dry U12n tunnel pond sediments below the mesa. Particle size analysis used a combination of sieving and optical diffraction techniques. Field-saturated hydraulic conductivity measurements employed a single-ring infiltrometer with analytical formulas that correct for falling head and spreading outside the ring domain. These measurements may prove useful to current and future efforts at Rainier Mesa aimed at understanding infiltration and its effect on water fluxes and radionuclide transport in the unsaturated zone.

  11. Reducing Uncertainty in the Distribution of Hydrogeologic Units within Volcanic Composite Units of Pahute Mesa Using High-Resolution 3-D Resistivity Methods, Nevada Test Site, Nevada

    USGS Publications Warehouse

    Rodriguez, Brian D.; Sweetkind, Don; Burton, Bethany L.

    2010-01-01

    The U.S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing groundwater contamination resulting from historical underground nuclear testing through the Environmental Management program and, in particular, the Underground Test Area (UGTA) project. From 1951 to 1992, 828 underground nuclear tests were conducted at the Nevada Test Site (NTS) northwest of Las Vegas (DOE UGTA, 2003). Most of these tests were conducted hundreds of feet above the groundwater table; however, more than 200 of the tests were near, or within, the water table. This underground testing was limited to specific areas of the NTS including Pahute Mesa, Rainier Mesa/Shoshone Mountain, Frenchman Flat, and Yucca Flat. Volcanic composite units make up much of the area within the Pahute Mesa Corrective Action Unit (CAU) at the NTS, Nevada. The extent of many of these volcanic composite units extends throughout and south of the primary areas of past underground testing at Pahute and Rainier Mesas. As situated, these units likely influence the rate and direction of groundwater flow and radionuclide transport. Currently, these units are poorly resolved in terms of their hydrologic properties introducing large uncertainties into current CAU-scale flow and transport models. In 2007, the U.S. Geological Survey (USGS), in cooperation with DOE and NNSA-NSO acquired three-dimensional (3-D) tensor magnetotelluric data at the NTS in Area 20 of Pahute Mesa CAU. A total of 20 magnetotelluric recording stations were established at about 600-m spacing on a 3-D array and were tied to ER20-6 well and other nearby well control (fig. 1). The purpose of this survey was to determine if closely spaced 3-D resistivity measurements can be used to characterize the distribution of shallow (600- to 1,500-m-depth range) devitrified rhyolite lava-flow aquifers (LFA) and zeolitic tuff confining units (TCU) in areas of limited drill hole control on Pahute Mesa within the Calico Hills zeolitic volcanic composite unit (VCU), an important hydrostratigraphic unit in Area 20. The resistivity response was evaluated and compared with existing well data and hydrogeologic unit tops from the current Pahute Mesa framework model. In 2008, the USGS processed and inverted the magnetotelluric data into a 3-D resistivity model. We interpreted nine depth slices and four west-east profile cross sections of the 3-D resistivity inversion model. This report documents the geologic interpretation of the 3-D resistivity model. Expectations are that spatial variations in the electrical properties of the Calico Hills zeolitic VCU can be detected and mapped with 3-D resistivity, and that these changes correlate to differences in rock permeability. With regard to LFA and TCU, electrical resistivity and permeability are typically related. Tuff confining units will typically have low electrical resistivity and low permeability, whereas LFA will have higher electrical resistivity and zones of higher fracture-related permeability. If expectations are shown to be correct, the method can be utilized by the UGTA scientists to refine the hydrostratigraphic unit (HSU) framework in an effort to more accurately predict radionuclide transport away from test areas on Pahute and Rainier Mesas.

  12. Predictions of Long-Term Radionuclide Transport at Rainier Mesa, Nevada National Security Site

    NASA Astrophysics Data System (ADS)

    Reeves, D. M.; Parashar, R.; Pohlmann, K. F.; LaBolle, E. M.; Zhang, Y.; Russell, C. E.; Chapman, J. B.

    2011-12-01

    Rainier Mesa, a tuffaceous plateau on the Nevada National Security Site, has been the location of numerous subsurface nuclear tests conducted in a series of tunnel complexes located approximately 400 m below the top of the mesa and 400 m above the regional groundwater flow system. The tunnels were constructed near the middle of an 800 m Tertiary sequence of faulted, low-permeability welded and non-welded bedded, vitric, and zeolitized tuff units. Water levels from wells in the vicinity of both the N- and T-tunnel complexes indicate the presence of two saturated zones. The first saturated zone has an elevation of approximately 1800 m (300 mbgs) and is located 100 m above the T-tunnel complex. Water level measurements during well construction and borehole moisture profiles of matrix saturation suggest this upper zone of saturation extends downward through most of the Tertiary sequence, though data is not available for the lowest Tertiary units. The second saturated zone is located at an elevation of 1300 m (800 mbgs) within a thrust sheet of Paleozoic carbonates and may be hydraulically connected to the Death Valley regional flow system. This study evaluates the potential for downward radionuclide transport associated with six underground tests at the T-tunnel complex over a 1000 year period. A dual-permeability (DKM) model containing spatially discontinuous fault networks within low-permeability tuff units is utilized to simulate complex patterns of variably-saturated flow. A modified random walk particle tracking code for DKM velocity fields is then used to compute radionuclide breakthrough at the regional water table (second saturated zone). Results include calibration of a variably-saturated model to field observations including water discharge history at the tunnel portal, variably-saturated fault fields, water levels in perched intervals and differential saturations in the volcanics and carbonates; and predictions of radionuclide breakthrough at the regional water table given uncertainty in fault network geometry, fault hydraulic properties, recharge and radionuclide adsorption and diffusion.

  13. Magnetotelluric Data, Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nevada

    USGS Publications Warehouse

    Williams, Jackie M.; Sampson, Jay A.; Rodriguez, Brian D.; Asch, Theodore H.

    2006-01-01

    Introduction: The United States Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing ground-water contamination resulting from historical underground nuclear testing through the Environmental Management (EM) program and, in particular, the Underground Test Area (UGTA) project. During 2005, the U.S. Geological Survey (USGS), in cooperation with the DOE and NNSA-NSO, collected and processed data from twenty-six magnetotelluric (MT) and audio-magnetotelluric (AMT) sites at the Nevada Test Site. The 2005 data stations were located on and near Rainier Mesa and Shoshone Mountain to assist in characterizing the pre-Tertiary geology in those areas. These new stations extend the area of the hydrogeologic study previously conducted in Yucca Flat. The MT data presented in this report will help refine what is known about the character, thickness, and lateral extent of pre Tertiary confining units. Subsequent interpretation will include a three dimensional (3 D) character analysis and a two-dimensional (2 D) resistivity model. The purpose of this report is to release the MT sounding data. No interpretation of the data is included here.

  14. GIS surface effects archive of underground nuclear detonations conducted at Yucca Flat and Pahute Mesa, Nevada Test Site, Nevada

    SciTech Connect

    Grasso, D.N.

    2001-11-02

    This report presents a new comprehensive, digital archive of more than 40 years of geologic surface effects maps produced at individual detonation sites throughout the Yucca Flat and Pahute Mesa nuclear testing areas of the Nevada Test Site, Nye County, Nevada. The Geographic Information System (GIS) surface effects map archive on CD-ROM (this report) comprehensively documents the surface effects of underground nuclear detonations conducted at two of the most extensively used testing areas of the Nevada Test Site. Between 1951 and 1992, numerous investigators of the U.S. Geological Survey, the Los Alamos National Laboratory, the Lawrence Livermore National Laboratory, and the Defense Threat Reduction Agency meticulously mapped the surface effects caused by underground nuclear testing. Their work documented the effects of more than seventy percent of the underground nuclear detonations conducted at Yucca Flat and all of the underground nuclear detonations conducted at Pahute Mesa.

  15. Simple estimation of minimum unsaturated contaminant travel times at Rainier Mesa and Shoshone Mountain, Nevada Test Site

    NASA Astrophysics Data System (ADS)

    Ebel, B. A.; Nimmo, J. R.

    2008-12-01

    In the unsaturated zone the fastest travel times frequently occur via preferential flow that bypasses the soil/rock matrix. Experimental data provide compelling evidence that minimum solute travel times through preferential paths depend primarily on whether water supply is continuous versus non-continuous in time, with little influence from matrix hydraulic properties. We employ a simple model based on this "source- responsive" paradigm to estimate minimum preferential travel times to the regional water table for nonreactive radionuclides at Rainier Mesa and Shoshone Mountain within the Nevada Test Site. The radionuclides at the site originate from underground nuclear testing within a ~1-km-thick unsaturated zone. Contaminated sources at Rainier Mesa and Shoshone Mountain that are continuously supplied include ponded water in certain tunnels, filled detention basins, and partially-filled boreholes with detonation cavities. Tunnels without ponding and unfilled detonation cavities are considered non-continuous sources supplied by percolation of precipitation. Decades of geological and hydrological characterizations provide the foundation for establishing preferential flow as a viable transport mechanism at Rainier Mesa and Shoshone Mountain Our estimated minimum travel times via preferential flow for Rainier Mesa are one to two months for a continuously-supplied source and tens to hundreds of years for a non-continuous source. Previous studies in the scientific literature conducted isotopic analysis of fracture water collected in tunnels at Rainier Mesa that indicated transit times for 400 m of transport from land surface to tunnel levels of one to 40 years. Four monitoring wells in the carbonate aquifer have not detected radionuclide levels above the drinking water standards at Rainier Mesa. Travel times for both the continuously and non-continuously supplied sources at Shoshone Mountain are twice the Rainier Mesa estimates, resulting from longer transport distances and less precipitation. A shale confining unit at Shoshone Mountain may cause a transition from preferential to matrix dominated flow, increasing estimated transport times to more than a thousand years. Concentrations of radionuclides above the drinking water standard have not been detected in a deep well or in springs at Shoshone Mountain. Preliminary results from our analysis indicate the potentially rapid nature of unsaturated-zone preferential transport (despite a semi-arid climate) for continuous sources and highlight the value of a simple modeling approach to complement traditional, more complex flow simulation approaches for contaminant travel time estimation.

  16. Sourcebook of locations of geophysical surveys in tunnels and horizontal holes, including results of seismic refraction surveys, Rainier Mesa, Aqueduct Mesa, and Area 16, Nevada Test Site

    USGS Publications Warehouse

    Carroll, R.D.; Kibler, J.E.

    1983-01-01

    Seismic refraction surveys have been obtained sporadically in tunnels in zeolitized tuff at the Nevada Test Site since the late 1950's. Commencing in 1967 and continuing to date (1982), .extensive measurements of shear- and compressional-wave velocities have been made in five tunnel complexes in Rainier and Aqueduct Mesas and in one tunnel complex in Shoshone Mountain. The results of these surveys to 1980 are compiled in this report. In addition, extensive horizontal drilling was initiated in 1967 in connection with geologic exploration in these tunnel complexes for sites for nuclear weapons tests. Seismic and electrical surveys were conducted in the majority of these holes. The type and location of these tunnel and borehole surveys are indexed in this report. Synthesis of the seismic refraction data indicates a mean compressional-wave velocity near the nuclear device point (WP) of 23 tunnel events of 2,430 m/s (7,970 f/s) with a range of 1,846-2,753 m/s (6,060-9,030 f/s). The mean shear-wave velocity of 17 tunnel events is 1,276 m/s (4,190 f/s) with a range of 1,140-1,392 m/s (3,740-4,570 f/s). Experience indicates that these velocity variations are due chiefly to the extent of fracturing and (or) the presence of partially saturated rock in the region of the survey.

  17. Micrometeorological and Soil Data for Calculating Evapotranspiration for Rainier Mesa, Nevada Test Site, Nevada 2002-05.

    SciTech Connect

    Guy A. DeMeo; Alan L. Flint; Randell J. Laczniak; Walter E. Nylund

    2006-12-28

    Micrometeorological and soil-moisture data were collected at two instrumented sites on Rainier Mesa at the Nevada Test Site, January 1, 2002/August 23, 2005. Data collected at each site include net radiation, air temperature, and relative humidity at two heights; wind speed and direction; subsurface soil heat flux; subsurface soil temperature; volumetric soil water; and matric water potential. These data were used to estimate 20-minute average and daily average evapotranspiration values. The data presented in this report are collected and calculated evapotranspiration rates.

  18. Micrometeorological and Soil Data for Calculating Evapotranspiration for Rainier Mesa, Nevada Test Site, Nevada, 2002-05

    USGS Publications Warehouse

    DeMeo, Guy A.; Flint, Alan L.; Laczniak, Randell J.; Nylund, Walter E.

    2006-01-01

    Micrometeorological and soil-moisture data were collected at two instrumented sites on Rainier Mesa at the Nevada Test Site, January 1, 2002 - August 23, 2005. Data collected at each site include net radiation, air temperature, and relative humidity at two heights; wind speed and direction; subsurface soil heat flux; subsurface soil temperature; volumetric soil water; and matric water potential. These data were used to estimate 20-minute average and daily average evapotranspiration values. The data presented in this report are collected and calculated evapotranspiration rates.

  19. Bacterial heterogeneity in deep subsurface tunnels at Rainier Mesa, Nevada test site.

    PubMed

    Haldeman, D L; Amy, P S

    1993-03-01

    To characterize the deep subsurface environment of Rainier Mesa, Nevada Test Site, rock samples were taken from tunnels U 12b, U12g, U12p, and U 12n, which varied in depth from 50 m to 450 m and in gravimetric moisture content from 4% to 27%. Values for total count, viable count, biomass, Simpson diversity, equitability, similarity coefficient, and number of distinct colony types indicated microbiological variability between samples. Viable counts ranged from less than 1 × 10(1) to 2.4 × 10(5) CFU g dry wt(-1) of rock. Direct counts and enumeration based on phospholipid determination indicated larger numbers of cells g dry wt-1 of rock than viable counts. Simpson diversity indices, equitability, and numbers of distinct colony types varied from 3.00 to 8.05, 0.21 to 0.89, and 7 to 19, respectively, and indicated heterogeneity between samples. Each distinct morphotype was purified and characterized. Gram reaction, morphology, metal and antibiotic resistances, and metabolic activities of each isolate confirmed spatial variability among microbiota isolated from different locations. Most probable numbers of nitrifying, sulfur oxidizing, and sulfur-reducing bacteria were below the limit of detection in all samples, while the numbers of nitrogen fixing bacteria ranged from below the level of detection to 7.8 × 10(2) cells g dry wt(-1) of rock sample, and the numbers of dentrifying bacteria ranged from below the level of detection to greater than 1.6 × 10(3) cells g dry wt(-1) of rock sample. PMID:24189814

  20. Corrective Action Investigation Plan for Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nevada with Errata and ROTC 1, Rev. No. 0

    SciTech Connect

    John McCord; Marutzky, Sam

    2004-12-01

    This Corrective Action Investigation Plan (CAIP) was developed for Corrective Action Unit (CAU) 99, Rainier Mesa/Shoshone Mountain. The CAIP is a requirement of the ''Federal Facility Agreement and Consent Order'' (FFACO) agreed to by the State of Nevada, the U.S. Department of Energy (DOE), and the U.S. Department of Defense (DoD) (FFACO, 1996). The FFACO addresses environmental restoration activities at U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) facilities and sites including the underground testing area(s) of the Nevada Test Site (NTS). This CAIP describes the investigation activities currently planned for the Rainier Mesa/Shoshone Mountain CAU. These activities are consistent with the current Underground Test Area (UGTA) Project strategy described in Section 3.0 of Appendix VI, Revision No. 1 (December 7, 2000) of the FFACO (1996) and summarized in Section 2.1.2 of this plan. The Rainier Mesa/Shoshone Mountain CAU extends over several areas of the NTS (Figure 1-1) and includes former underground nuclear testing locations in Areas 12 and 16. The area referred to as ''Rainier Mesa'' includes the geographical area of Rainier Mesa proper and the contiguous Aqueduct Mesa. Figure 1-2 shows the locations of the tests (within tunnel complexes) conducted at Rainier Mesa. Shoshone Mountain is located approximately 20 kilometers (km) south of Rainier Mesa, but is included within the same CAU due to similarities in their geologic setting and in the nature and types of nuclear tests conducted. Figure 1-3 shows the locations of the tests conducted at Shoshone Mountain. The Rainier Mesa/Shoshone Mountain CAU falls within the larger-scale Rainier Mesa/Shoshone Mountain Investigation Area, which also includes the northwest section of the Yucca Flat CAU as shown in Figure 1-1. Rainier Mesa and Shoshone Mountain lie adjacent to the Timber Mountain Caldera Complex and are composed of volcanic rocks that erupted from the caldera as well as from more distant sources. This has resulted in a layered volcanic stratigraphy composed of thick deposits of welded and nonwelded ash-flow tuff and lava flows. These deposits are proximal to the source caldera and are interstratified with the more distal facies of fallout tephra and bedded reworked tuff from more distant sources. In each area, a similar volcanic sequence was deposited upon Paleozoic carbonate and siliciclastic rocks that are disrupted by various thrust faults, normal faults, and strike-slip faults. In both Rainier Mesa (km) to the southwest, and Tippipah Spring, 4 km to the north, and the tunnel complex is dry. Particle-tracking simulations performed during the value of information analysis (VOIA) (SNJV, 2004b) indicate that most of the regional groundwater that underlies the test locations at Rainier Mesa and Shoshone Mountain eventually follows similar and parallel paths and ultimately discharges in Death Valley and the Amargosa Desert. Particle-tracking simulations conducted for the regional groundwater flow and risk assessment indicated that contamination from Rainier Mesa and Shoshone Mountain were unlikely to leave the NTS during the 1,000-year period of interest (DOE/NV, 1997a). It is anticipated that CAU-scale modeling will modify these results somewhat, but it is not expected to radically alter the outcome of these previous particle-tracking simulations within the 1,000-year period of interest. The Rainier Mesa/Shoshone Mountain CAIP describes the corrective action investigation (CAI) to be conducted at the Rainier Mesa/Shoshone Mountain CAU to evaluate the extent of contamination in groundwater due to the underground nuclear testing. The CAI will be conducted by the UGTA Project, which is part of the NNSA/NSO Environmental Restoration Project (ERP). The purpose and scope of the CAI are presented in this section, followed by a summary of the entire document.

  1. 23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL ...

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

    23. VIEW OF HORSE MESA DAM, SHOWING SPILLWAY DISCHARGE TUNNEL AT LEFT, RIGHT (OR NORTH) SPILLWAY, HEFU POWER UNIT, AND ORIGINAL POWER PLANT - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  2. 24. CLOSEUP VIEW OF HORSE MESA DAM. HEFU PENSTOCK IS ...

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

    24. CLOSE-UP VIEW OF HORSE MESA DAM. HEFU PENSTOCK IS AT CENTER RIGHT, AND LEFT (OR SOUTH) SPILLWAY CHUTE IS AT UPPER RIGHT - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  3. 6. VIEW OF UPSTREAM FACE OF HORSE MESA, SHOWING CONCRETE ...

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

    6. VIEW OF UPSTREAM FACE OF HORSE MESA, SHOWING CONCRETE BEING PLACED. PENSTOCK OPENINGS ARE VISIBLE AT CENTER LEFT. August 24, 1926 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  4. 20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY ...

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

    20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY SUPERSTRUCTURE AND CONCRETE PLACEMENT LINES August 2, 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  5. 22. VIEW SHOWING THE COMPLETED HORSE MESA DAM, EXCEPT FOR ...

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

    22. VIEW SHOWING THE COMPLETED HORSE MESA DAM, EXCEPT FOR TRANSFORMER EQUIPMENT BEING INSTALLED ABOVE THE POWER PLANT 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  6. 36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER ...

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

    36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER PLANT, LOOKING NORTH. ONLY TWO OF THE THREE UNITS ARE VISIBLE - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  7. Data Report: Meteorological and Evapotranspiration Data from Sagebrush and Pinyon Pine/Juniper Communities at Pahute Mesa, Nevada National Security Site, 2011-2012

    SciTech Connect

    Jasoni, Richard L; Larsen, Jessica D; Lyles, Brad F.; Healey, John M; Cooper, Clay A; Hershey, Ronald L; Lefebre, Karen J

    2013-04-01

    Pahute Mesa is a groundwater recharge area at the Nevada National Security Site. Because underground nuclear testing was conducted at Pahute Mesa, groundwater recharge may transport radionuclides from underground test sites downward to the water table; the amount of groundwater recharge is also an important component of contaminant transport models. To estimate the amount of groundwater recharge at Pahute Mesa, an INFIL3.0 recharge-runoff model is being developed. Two eddy covariance (EC) stations were installed on Pahute Mesa to estimate evapotranspiration (ET) to support the groundwater recharge modeling project. This data report describes the methods that were used to estimate ET and collect meteorological data. Evapotranspiration was estimated for two predominant plant communities on Pahute Mesa; one site was located in a sagebrush plant community, the other site in a pinyon pine/juniper community. Annual ET was estimated to be 310±13.9 mm for the sagebrush site and 347±15.9 mm for the pinyon pine/juniper site (March 26, 2011 to March 26, 2012). Annual precipitation measured with unheated tipping bucket rain gauges was 179 mm at the sagebrush site and 159 mm at the pinyon pine/juniper site. Annual precipitation measured with bulk precipitation gauges was 222 mm at the sagebrush site and 227 mm at the pinyon pine/juniper site (March 21, 2011 to March 28, 2012). A comparison of tipping bucket versus bulk precipitation data showed that total precipitation measured by the tipping bucket rain gauges was 17 to 20 percent lower than the bulk precipitation gauges. These differences were most likely the result of the unheated tipping bucket precipitation gauges not measuring frozen precipitation as accurately as the bulk precipitation gauges. In this one-year study, ET exceeded precipitation at both study sites because estimates of ET included precipitation that fell during the winter of 2010-2011 prior to EC instrumentation and the precipitation gauges started collecting data in March 2011.

  8. Development of Phenomenological Models of Underground Nuclear Tests on Pahute Mesa, Nevada Test Site - BENHAM and TYBO

    SciTech Connect

    Pawloski, G.A.

    1999-09-21

    Although it is well accepted that underground nuclear explosions modify the in situ geologic media around the explosion point, the details of these changes are neither well understood nor well documented. As part of the engineering and containment process before a nuclear test, the physical environment is characterized to some extent to predict how the explosion will interact with the in situ media. However, a more detailed characterization of the physical environment surrounding an expended site is needed to successfully model radionuclide transport in the groundwater away from the detonation point. It is important to understand how the media have been altered and where the radionuclides are deposited. Once understood, this information on modified geologic media can be incorporated into a phenomenological model that is suitable for input to computer simulations of groundwater flow and radionuclide transport. The primary goals of this study are to (1) identify the modification of the media at a pertinent scale, and (2) provide this information to researchers modeling radionuclide transport in groundwater for the US Department of Energy (DOE) Nevada Operations Office Underground Test Area (UGTA) Project. Results from this study are most applicable at near-field scale (a model domain of about 500 m) and intermediate-field scale (a model domain of about 5 km) for which detailed information can be maximized as it is incorporated in the modeling grids. UGTA collected data on radionuclides in groundwater during recent drilling at the ER-20-5 site, which is near BENHAM and TYBO on Pahute Mesa at the Nevada Test Site (NTS). Computer simulations are being performed to better understand radionuclide transport. The objectives of this modeling effort include: evaluating site-specific information from the BENHAM and TYBO tests on Pahute Mesa; augmenting the above data set with generalized containment data; and developing a phenomenological model suitable for input to groundwater flow and transport modeling efforts that describes the physical in situ environment after the BENHAM and TYBO nuclear explosions.

  9. VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST ...

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

    VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST TOWER VIEW INCLUDES STRUCTURAL DYNAMICS TEST STAND COLD CALIBRATION TEST STAND AND COMPONENTS TEST LAB. - Marshall Space Flight Center, East Test Area, Dodd Road, Huntsville, Madison County, AL

  10. VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST ...

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

    VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST TOWER VIEW INCLUDES SATURN V STAND (BACKGROUND), BLOCK HOUSE (MIDDLE GROUND), STRUCTURAL DYNAMICS TEST STAND (FAR RIGHT). - Marshall Space Flight Center, East Test Area, Dodd Road, Huntsville, Madison County, AL

  11. 4. VIEW FROM RADAR SITE, LOOKING EAST, SHOWING BARRACKS ON ...

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

    4. VIEW FROM RADAR SITE, LOOKING EAST, SHOWING BARRACKS ON LEFT, LAUNCH ON RIGHT Everett Weinreb, photographer, April 1988 - Los Pinetos Nike Missile Site, Santa Clara Road, Los Angeles National Forest, Sylmar, Los Angeles County, CA

  12. 1. AERIAL VIEW, LOOKING EAST, SHOWING DETAILS OF RADAR SITE ...

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

    1. AERIAL VIEW, LOOKING EAST, SHOWING DETAILS OF RADAR SITE IN FOREGROUND Everett Weinreb, photographer, April 1988 - Los Pinetos Nike Missile Site, Santa Clara Road, Los Angeles National Forest, Sylmar, Los Angeles County, CA

  13. Value of information analysis for Corrective Action Unit Nos. 101 and 102: Central and western Pahute Mesa, Nevada Test Site, Nevada

    SciTech Connect

    1998-09-01

    The purpose of this report is to describe the basis for and present the results of a value of information analysis (VOIA) for the Pahute Mesa underground test area of the Nevada Test Site (NTS), one of several areas of the Nevada Test Site used for underground nuclear testing in the past. The value of information analysis was used to evaluate and compare potential characterization options at the Pahute Mesa underground test area for site remediation purposes. Thirty six characterization options were evaluated, ranging from a single, inexpensive study using existing data and intended to address a single question or uncertainty, to a forty-million-dollar suite of activities designed to collect and analyze new information to address multiple uncertainties. The characterization options were compared and ranked based on how effective the experts though the information collection would be in reducing uncertainties, how this effected the distance to contaminant boundary, and the cost of the option.

  14. Deep Vadose Zone Flow and Transport Behavior at T-Tunnel Complex, Rainier Mesa, Nevada National Security Site

    NASA Astrophysics Data System (ADS)

    Parashar, R.; Reeves, D. M.

    2010-12-01

    Rainier Mesa, a tuffaceous plateau on the Nevada National Security Site, has been the location of numerous subsurface nuclear tests conducted in a series of tunnel complexes located approximately 450 m below the top of the mesa and 500 m above the regional groundwater flow system. The tunnels were constructed near the middle of an 800 m Tertiary sequence of faulted, low-permeability welded and non-welded bedded, vitric, and zeolitized tuff units. Water levels from wells in the vicinity of the T-tunnel complex indicate the presence of a perched saturation zone located approximately 100 m above the T-tunnel complex. This upper zone of saturation extends downward through most of the Tertiary sequence. The groundwater table is located at an elevation of 1300 m within a thrust sheet of Paleozoic carbonates, corresponding to the lower carbonate aquifer hydrostratigraphic unit (LCA3). The LCA3 is considered to be hydraulically connected to the Death Valley regional flow system. The objective of this project is to simulate complex downward patterns of fluid flow and radionuclide transport from the T-tunnel complex through the matrix and fault networks of the Tertiary tuff units to the water table. We developed an improved fracture characterization and mapping methodology consisting of displacement-length scaling relationships, simulation of realistic fault networks based on site-specific data, and the development of novel fracture network upscaling techniques that preserves fracture network flow and transport properties on coarse continuum grid. Development of upscaling method for fracture continua is based on the concepts of discrete fracture network modeling approach which performs better at honoring network connectivity and anisotropy of sparse networks in comparison to other established methods such as a tensor approach. Extensive flow simulations in the dual-continuum framework demonstrate that the characteristics of fault networks strongly influences the saturation profile and formation of perched zones, although they may not conduct a large amount of flow when compared to the matrix continua. The simulated results are found to be very sensitive to distribution of fracture aperture, density of the network, and spatial pattern of fracture clustering. The faults provide rapid pathways for radionuclide transport and the conceptual modeling of diffusional mass transfer between matrix and fracture continua plays a vital role in prediction of the overall behavior of the breakthrough curve.

  15. Evaluation of the Hydrologic Source Term from Underground Nuclear Tests on Pahute Mesa at the Nevada Test Site: The CHESHIRE Test

    SciTech Connect

    Pawloski, G A; Tompson, A F B; Carle, S F; Bourcier, W L; Bruton, C J; Daniels, J I; Maxwell, R M; Shumaker, D E; Smith, D K; Zavarin, M

    2001-05-01

    The objectives of this report are to develop, summarize, and interpret a series of detailed unclassified simulations that forecast the nature and extent of radionuclide release and near-field migration in groundwater away from the CHESHIRE underground nuclear test at Pahute Mesa at the NTS over 1000 yrs. Collectively, these results are called the CHESHIRE Hydrologic Source Term (HST). The CHESHIRE underground nuclear test was one of 76 underground nuclear tests that were fired below or within 100 m of the water table between 1965 and 1992 in Areas 19 and 20 of the NTS. These areas now comprise the Pahute Mesa Corrective Action Unit (CAU) for which a separate subregional scale flow and transport model is being developed by the UGTA Project to forecast the larger-scale migration of radionuclides from underground tests on Pahute Mesa. The current simulations are being developed, on one hand, to more fully understand the complex coupled processes involved in radionuclide migration, with a specific focus on the CHESHIRE test. While remaining unclassified, they are as site specific as possible and involve a level of modeling detail that is commensurate with the most fundamental processes, conservative assumptions, and representative data sets available. However, the simulation results are also being developed so that they may be simplified and interpreted for use as a source term boundary condition at the CHESHIRE location in the Pahute Mesa CAU model. In addition, the processes of simplification and interpretation will provide generalized insight as to how the source term behavior at other tests may be considered or otherwise represented in the Pahute Mesa CAU model.

  16. Database of Ground-Water Levels in the Vicinity of Rainier Mesa, Nevada Test Site, Nye County, Nevada 1957-2005.

    SciTech Connect

    Joseph M. Fenelon

    2006-08-15

    More than 1,200 water-level measurements from 1957 to 2005 in the Rainier Mesa area of the Nevada Test Site were quality assured and analyzed. Water levels were measured from 50 discrete intervals within 18 boreholes and from 4 tunnel sites. An interpretive database was constructed that describes water-level conditions for each water level measured in the Rainier Mesa area. Multiple attributes were assigned to each water-level measurement in the database to describe the hydrologic conditions at the time of measurement. General quality, temporal variability, regional significance, and hydrologic conditions are attributed for each water-level measurement. The database also includes hydrograph narratives that describe the water-level history of each well.

  17. VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST ...

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

    VIEW OF EAST TEST SITE FROM TOP OF STATIC TEST TOWER VIEW INCLUDES POWER PLANT TEST STAND AND SATURN V TEST STAND IN THE WEST TEST AREA (FAR BACKGROUND). - Marshall Space Flight Center, East Test Area, Dodd Road, Huntsville, Madison County, AL

  18. 11. STATION "0" ELECTRICAL SUBSTATION SITE AT EAST END OF ...

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

    11. STATION "0" ELECTRICAL SUBSTATION SITE AT EAST END OF TRACK. Looking north from top of berm to Fire Station No. 3 (Survival School, Building 0510). - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  19. 12. View of Dry Dock No. 4 site, looking east, ...

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

    12. View of Dry Dock No. 4 site, looking east, excavations nearing completion. Note concrete floor already poured and excavated steps in walls for counterfort retaining walls (12/17/42). Photographer unknown. - Hunters Point Naval Shipyard, Drydock No. 4, East terminus of Palou Avenue, San Francisco, San Francisco County, CA

  20. The Underground Test Area Project of the Nevada Test Site: Building Confidence in Groundwater Flow and Transport Models at Pahute Mesa Through Focused Characterization Studies

    SciTech Connect

    Pawloski, G A; Wurtz, J; Drellack, S L

    2009-12-29

    Pahute Mesa at the Nevada Test Site contains about 8.0E+07 curies of radioactivity caused by underground nuclear testing. The Underground Test Area Subproject has entered Phase II of data acquisition, analysis, and modeling to determine the risk to receptors from radioactivity in the groundwater, establish a groundwater monitoring network, and provide regulatory closure. Evaluation of radionuclide contamination at Pahute Mesa is particularly difficult due to the complex stratigraphy and structure caused by multiple calderas in the Southwestern Nevada Volcanic Field and overprinting of Basin and Range faulting. Included in overall Phase II goals is the need to reduce the uncertainty and improve confidence in modeling results. New characterization efforts are underway, and results from the first year of a three-year well drilling plan are presented.

  1. View from east to west of PAR site storage building; ...

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

    View from east to west of PAR site storage building; formerly PAR dispensary - Stanley R. Mickelsen Safeguard Complex, Storage Building, Across street from Family Housing Units 110 & 111, Nekoma, Cavalier County, ND

  2. View from west to east of PAR site resident engineer's ...

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

    View from west to east of PAR site resident engineer's office building (REOB) - Stanley R. Mickelsen Safeguard Complex, Resident Engineers Office Building, Southeast of intersection of PAR Access Road & Fourth Avenue, Nekoma, Cavalier County, ND

  3. Modeling the fate of radionuclides in the unsaturated zone at the Nevada Test Site: Examples from Yucca Flat and Rainier Mesa

    NASA Astrophysics Data System (ADS)

    Kwicklis, E. M.; Dash, Z. V.; Viswanathan, H. S.; Levitt, D. G.; Lu, Z.; Dai, Z.; Zyvoloski, G.; Gable, C. W.; Miller, T. A.

    2010-12-01

    The Nevada Test Site (NTS), located 105 km northwest of Las Vegas, Nevada, hosted 828 underground nuclear explosions between 1951 and 1992, leaving an estimated 1.3e+08 curies of tritium, fission products, activation products and unspent fuel in the subsurface when the nuclear test moratorium was adopted in September, 1992. In two former testing areas of the NTS - Yucca Flat and Rainier Mesa- a significant fraction of the initial radionuclide inventory was introduced from nuclear tests with working points in the unsaturated zone. In Yucca Flat, an arid, low-elevation alluvium-filled basin where most tests were conducted in vertical shafts, unsaturated flow and transport models indicate that radionuclide migration to the water table is most likely where overlying subsidence craters receive significant infiltration from overland flow during infrequent runoff events. At Rainier Mesa, a wetter, high-elevation remnant of a once more extensive volcanic plateau, most tests were conducted at the ends of horizontal drifts in the vicinity of local perched water zones. Unsaturated flow and transport models of one of the larger tunnel complexes (N-tunnel) indicate that despite relatively high infiltration rates on the mesa, radionuclide diffusion from the flowing fractures to the porous matrix may significantly attenuate radionuclide movement to the water table.

  4. Analysis of fractures in volcanic cores from Pahute Mesa, Nevada Test Site

    SciTech Connect

    Drellack, S.L. Jr.; Prothro, L.B.; Roberson, K.E.

    1997-09-01

    The Nevada Test Site (NTS), located in Nye County, southern Nevada, was the location of 828 announced underground nuclear tests, conducted between 1951 and 1992. Approximately one-third of these tests were detonated near or below the water table. An unavoidable consequence of these testing activities was introducing radionuclides into the subsurface environment, impacting groundwater. Groundwater flows beneath the NTS almost exclusively through interconnected natural fractures in carbonate and volcanic rocks. Information about these fractures is necessary to determine hydrologic parameters for future Corrective Action Unit (CAU)-specific flow and transport models which will be used to support risk assessment calculations for the U.S. Department of Energy, Nevada Operations Office (DOE/NV) Underground Test Area (UGTA) remedial investigation. Fracture data are critical in reducing the uncertainty of the predictive capabilities of CAU-specific models because of their usefulness in generating hydraulic conductivity values and dispersion characteristics used in transport modeling. Specifically, fracture aperture and density (spacing) are needed to calculate the permeability anisotropy of the formations. Fracture mineralogy information is used qualitatively to evaluate diffusion and radionuclide retardation potential in transport modeling. All these data can best be collected through examination of core samples.

  5. 49. HORSE MESA DAM, AUXILIARY SPILLWAY, 40.0' x 44.5' REGULATING ...

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

    49. HORSE MESA DAM, AUXILIARY SPILLWAY, 40.0' x 44.5' REGULATING GATE HOIST. INSTALLATION ASSEMBLY February 3, 1937 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  6. Flow and Radionuclide Transport Models of the Unsaturated Zone at the Nevada National Security Site: Examples from Yucca Flat and Rainier Mesa

    NASA Astrophysics Data System (ADS)

    Kwicklis, E. M.; Viswanathan, H. S.; Levitt, D. G.; Dash, Z.; Gable, C. W.; Lu, Z.; Dai, Z.; Zyvoloski, G.; Miller, T. A.

    2011-12-01

    The former Nevada Test Site (now the Nevada National Security Site) hosted 828 underground nuclear explosions between 1951 and 1992, leaving an estimated 1.3e+08 curies of tritium, fission products, activation products and unspent fuel in the subsurface when the nuclear test moratorium was adopted in September, 1992. In two former testing areas of the Nevada National Security Site - Yucca Flat and Rainier Mesa- a significant fraction of the initial radionuclide inventory was introduced from nuclear tests with working points in the unsaturated zone. In Yucca Flat, an arid, low-elevation alluvium-filled basin where most tests were conducted in vertical shafts, unsaturated flow and transport models indicate that radionuclide migration to the water table is most likely where overlying subsidence craters receive significant infiltration from overland flow during infrequent runoff events. These craters tend to be located along the perimeter of the basin and have large contributing watersheds in the surrounding hills. At Rainier Mesa, a wetter, high-elevation remnant of a once more extensive volcanic plateau, most tests were conducted at the ends of horizontal drifts in the vicinity of local perched water zones. Unsaturated flow and transport models of one of the larger tunnel complexes (N-tunnel) indicate that despite relatively high infiltration rates on the mesa, radionuclide diffusion from the flowing fractures to the porous matrix may significantly attenuate radionuclide movement to the water table, depending on the assumed fracture attributes. Simulations show that the tunnel itself may be an important hydraulic feature that connects radionuclide sources to sub-vertical faults that are assumed to extend to the water table.

  7. 9. VIEW OF SITE B FROM EAST END OF ANDERSON ...

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

    9. VIEW OF SITE B FROM EAST END OF ANDERSON WAY, FACING WEST (BUILDINGS 126, 128, 129, 130, and 131 ARE VISIBLE.) - Fort McPherson, World War II Station Hospital, Structures, Bordered by Hardee & Thorne Avenues & Howe Street, Atlanta, Fulton County, GA

  8. 2. EAST SIDE; LOOKING WEST FROM SITE OF STOCKYARDS; UPPER ...

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

    2. EAST SIDE; LOOKING WEST FROM SITE OF STOCKYARDS; UPPER LEFT CORNER WAS ORIGINALLY ATTACHED TO SHEEP HOTEL (BUILDING 142); UPPER RIGHT CORNER WAS ORIGINALLY ATTACHED TO HOG HOTEL (BUILDING 138) - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  9. 5. Long view of east half of site from Lawrence ...

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

    5. Long view of east half of site from Lawrence General Hospital parking deck (former location of coating mill) showing north side of Clay Storage Silos and northeast block of Wilder Mill; view to southwest. - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

  10. 14. VIEW SHOWING UPSTREAM FACE OF HORSE MESA. TRACK FROM ...

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

    14. VIEW SHOWING UPSTREAM FACE OF HORSE MESA. TRACK FROM AGGREGATE BARGES TO MIXING PLANT IS AT LOWER LEFT, RIGHT SPILLWAY CHUTE IS TAKING FORM AT UPPER RIGHT April 29, 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  11. Quality assurance and analysis of water levels in wells on Pahute Mesa and vicinity, Nevada Test Site, Nye County, Nevada

    USGS Publications Warehouse

    Fenelon, Joseph M.

    2000-01-01

    Periodic and continual water-level data from 1963 to 1998 were compiled and quality assured for 65 observation wells on Pahute Mesa and vicinity, Nye County, Nevada. As part of the quality assurance of all water levels, ancillary data pertinent to computing hydraulic heads in wells were compiled and analyzed. Quality-assured water levels that were not necessarily in error but which did not represent static heads in the regional aquifer system, or required some other qualification, were flagged. Water levels flagged include those recovering from recent pumping or well construction, water levels affected by nuclear tests, and measurements affected by borehole deviations. A cursory examination of about 30 wells with available water-level and down-hole temperature data indicate that water levels in most wells on Pahute Mesa would not be significantly affected by temperature if corrected to 95 degrees Fahrenheit. Wells with large corrections (greater than 10 feet) are those with long water columns (greater than 1,500 feet of water above the assumed point of inflow) in combination with mean water-column temperatures exceeding 105 degrees Fahrenheit. Water-level fluctuations in wells on Pahute Mesa are caused by several factors including infiltration of precipitation, barometric pressure, Earth tides, ground-water pumpage, and seismic events caused by tectonic activity and underground nuclear testing. No observed water-level fluctuations were attributed to a naturally occurring earthquake. The magnitude and duration of changes in water levels caused by nuclear tests are affected by the test size and the distance from a well to the test. Identifying water levels that might be affected by past nuclear tests is difficult because pre-testing water-level data are sparse. Hydrologically significant trends were found in 13 of 25 wells with multiple years of water-level record. The largest change in water levels (1,029 feet in 25 years) occurred in well U-19v PS 1D as a result of the Almendro nuclear test. Likely explanations for trends in most of the wells are either changes in precipitation patterns that affect recharge rates to the ground-water system, pumping effects from water-supply well U-20 WW, or a combination of these two factors.

  12. 27 CFR 9.195 - Alta Mesa.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Alta Mesa... Route 99 to its intersection with Sheldon Road at the northern boundary of section 26, T7N, R5E (Florin Quadrangle); then (3) Proceed east 5.2 miles on Sheldon Road to its intersection with the Central...

  13. 27 CFR 9.195 - Alta Mesa.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Alta Mesa... Route 99 to its intersection with Sheldon Road at the northern boundary of section 26, T7N, R5E (Florin Quadrangle); then (3) Proceed east 5.2 miles on Sheldon Road to its intersection with the Central...

  14. 27 CFR 9.195 - Alta Mesa.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Alta Mesa... Route 99 to its intersection with Sheldon Road at the northern boundary of section 26, T7N, R5E (Florin Quadrangle); then (3) Proceed east 5.2 miles on Sheldon Road to its intersection with the Central...

  15. 27 CFR 9.195 - Alta Mesa.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Alta Mesa... Route 99 to its intersection with Sheldon Road at the northern boundary of section 26, T7N, R5E (Florin Quadrangle); then (3) Proceed east 5.2 miles on Sheldon Road to its intersection with the Central...

  16. 27 CFR 9.195 - Alta Mesa.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... County, California, and is entirely within the Lodi viticultural area (27 CFR 9.107). The Alta Mesa... Route 99 to its intersection with Sheldon Road at the northern boundary of section 26, T7N, R5E (Florin Quadrangle); then (3) Proceed east 5.2 miles on Sheldon Road to its intersection with the Central...

  17. Remedial actions at the former Climax Uranium Company, Uranium Mill site, Grand Junction, Mesa County, Colorado. Volume 1, Text: Final environmental impact statement

    SciTech Connect

    1986-12-01

    This statement evaluates and compares the environmental impacts associated with the remedial actions of the residual radioactive materials remaining at the inactive uranium processing site and associated vicinity properties at Grand Junction, Mesa County, Colorado. This statement is also intended to aid the BLM in amending their management framework plans and final resource management plan, as well as assisting in compliance with the withdrawal application as appropriate. The site is a 114-acre tract of private and state owned land which contains approximately 3.1 million cubic yards of tailings and associated contaminated soils. The vicinity properties are homes, businesses, public buildings, and vacant lots which may have been contaminated during construction by the use of tailings as building material. An estimated 3465 vicinity properties would be cleaned up during remedial action of the tailings pile. The tailings were produced by the former Climax Uranium Company which processed uranium ore, which it sold to the US Atomic Energy Commission from 1951 to 1966 and to private sources from 1966 to 1970. This statement evaluates six alternatives for stabilization and disposal of the tailings and other contaminated materials: (1) No action. (2) Stabilization at the Grand Junction site. (3) Disposal at the Cheney Reservoir site with truck transport. (4) Disposal at the Cheney Reservoir site with train and truck transport. (5) Disposal at the Two Road site with truck transport. (6) Disposal at the Two Road site with train and truck transport. All of the alternatives except no action include remedial action at an estimated 3465 vicinity properties. Alternative 3 is DOE`s preferred alternative.

  18. Analysis of the Variability of Classified and Unclassified Radiological Source term Inventories in the Rainier Mesa/Shoshone Mountain Area, Nevada Test Site

    SciTech Connect

    Zhao, P; Zavarin, M

    2008-06-04

    It has been proposed that unclassified source terms used in RM/SM reactive transport modeling investigations should be based on yield-weighted source terms calculated using the RM/SM average source term from Bowen et al. (2001) and the unclassified announced yields reported in DOE/NV-209. This unclassified inventory is likely to be used in unclassified contaminant boundary calculations and is, thus, relevant to compare to the classified inventory. They have examined the classified radionuclide inventory produced by 73 underground nuclear tests conducted in the Rainier Mesa/Shoshone Mountain (RM/SM) area of the Nevada Test Site. The goals were to (1) evaluate the variability in classified radiological source terms among the 73 tests and (2) and compare that variability and inventory uncertainties to an average unclassified inventory (e.g. Bowen 2001). To evaluate source term variability among the 73 tests, radiological inventories were compared on two relative scales: geometric mean and yield-weighted geometric mean. Furthermore, radiological inventories were either decay corrected to a common date (9/23/1992) or the time zero (t{sub 0}) of each test. Thus, a total of four data sets were produced. The date of 9/23/1992 was chosen based on the date of the last underground nuclear test at the Nevada Test Site.

  19. Estimation of Unsaturated Zone Traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, Using a Source-Responsive Preferential-Flow Model

    USGS Publications Warehouse

    Ebel, Brian A.; Nimmo, John R.

    2009-01-01

    Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of th

  20. Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model

    SciTech Connect

    Brian A. Ebel; John R. Nimmo

    2009-09-11

    Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of these end members.

  1. Mesa Verde Archaeoastronomy

    NASA Astrophysics Data System (ADS)

    Munson, Gregory E.

    Mesa Verde archaeoastronomy has been studied for over 100 years through academic research. Investigators have excavated, stabilized, and documented the major dwellings in Mesa Verde National Park. Evidence for astronomical orientation and alignment was found in Cliff Palace and Sun Temple. The level of documentation increased with each new research project. With good documentation practices, together, the research has shown that the cultures of the Mesa Verde were advanced in their social organization and use of astronomy. Consultation with Native American tribal leaders will add significant background to the depth of knowledge that their ancestors possessed.

  2. Addendum for the Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, Revision 0 (page changes)

    SciTech Connect

    John McCord

    2007-05-01

    This document, which makes changes to Groundwater Flow Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada, S-N/99205--076, Revision 0 (June 2006) was prepared to address review comments of this final document by the Nevada Division of Environmental Protection (NDEP) in a letter dated July 19, 2006. The document includes revised pages that address NDEP review comments and comments from other document users. Change bars are included on these pages to identify where the text was revised. In addition to the revised pages, the following clarifications are made: • On Plate 1 (inserted in the back of the document), the ET Unit legend has been revised. The revised Plate 1 is included and replaces the original Plate 1. • Some of the Appendix D perturbation sensitivity analysis plots included on the CD for Sections D.3.1 and D.3.2 were not properly aligned. A revised CD is provided with all plots properly aligned.

  3. Soils and geomorphology of the East Chestnut Ridge site

    SciTech Connect

    Lietzke, D.A.; Ketelle, R.H.; Lee, R.R. , Rutledge, TN; Oak Ridge National Lab., TN )

    1989-10-01

    Soil mapping of the East Chestnut Ridge site in conjunction with subsurface soil and rock coring provides an in-depth evaluation of the site and its suitability for disposal of wastes. Landforms and surface and subsurface hydrology, the natural, undisturbed, soil-saprolite-geohydrology system beneath the zone of engineering modifications provides for the ultimate containment of wastes and a means for the filtration and purification of any leachate before it reaches the aquifer. The surface location and extent of each geologic formation on the site were mapped. These locations correlated well with projections of subsurface contacts to the surface even through the criteria used by the pedologist and geologist to identify soil and rock from the same formation may be different. Soil thickness over bedrock of the Copper Ridge, Chepultepec, Longview, and Kingsport Formations is sufficient to provide considerable buffering between trench bottoms and groundwater or rock. Soil thickness over the Mascot Formation is comparatively thin, and pinnacles and ledges exposed on steeper sideslopes are common. Soil underlain by the Mascot Formation is not suited for a trench landfill. According to soil coring and active borrow pit observations, chert beds in the soil and saprolite are preferred zones of water flow. Construction of adequate clay liners beneath disposal units sited on the Longview dolomite may require placement and compaction of other native soils to achieve sufficiently low soil permeabilities. Karst geomorphic processes that initiated the formation of dolines evidently started several million years ago. Doline formation and enlargement is episodic, with short periods of activity followed by long periods of stability. Analysis of doline soil stratigraphy suggests that most of the large dolines on the site have been stable for most of the past 10,000 to 1000,000 years. 8 refs., 9 figs.

  4. Digital reconstruction on geographical environment of Neolithic human activities in the Lingjiatan site of Chaohu City, East China

    NASA Astrophysics Data System (ADS)

    Wang, Xinyuan; Zhang, Jie; Wu, Li; Zhou, Kunshu; Mo, Duowen

    2010-11-01

    The Chaohu Lake Basin is an important area for ancient human activities in East China. The Lingjiatan site, which is located at the southeast of Chaohu City, Anhui Province, and 35 km north to the Yangtze River and 5 km south to the Taihu Mountain, is the most representative Neolithic Age site with advanced jade-carving techniques in this area. The 14C date of Lingjiatan Site is about 5600~5300aBP, the same time as the Hongshan culture and earlier than the Liangzhu culture, which falls into the Mid-Holocene epoch. Based on mid-high resolution remote sensing images and former archaeological materials, combined with field investigations and sampling analysis of the archaeological site profile of Lingjiatan Site as well as core drillings in the Chaohu Lake, the paper reconstructs the climate environment of the Lingjiatan site and the environmental background of ancient human activities during Mid-Holocene. The research results show that: (1) The ancients in Lingjiatan lived in the Holocene Optimum, its culture development was during the interim phase when the climate transformed from warm and wet to cool and dry. (2) The ground surface deposited in the last phase of late Pleistocene epoch (OSL dating is 11.6 +/-1.0 ka BP) was the living ground for Lingjiatan ancient humans. The sedimentary discontinuous surface may be caused by strong fluvial erosion under the warm and humid climatic conditions of the Mid-Holocene. (3) Originally, paleo-geomorphic surface was a level shallow mesa foreside southern part of Taihu Mountain, but was cut by fluvial waters and the geomorphologic configuration formed "finger-like" features alternately with strip hillocks and rivers. These features can be seen on the Landsat ETM+ remote sensing image, especially the depression area. This depression is now cropland, and was interpreted as the palaeochannels. (4) Based on the remote sensing image interpretation, the site was in a "peninsula shape" environment which had rivers flowing around the east, west and south sides of the Changgang terrain and that was good for rice planting, hunting, fishing and water transportation. (5) The most particular characteristic of the Lingjiatan site is the advanced jade production, those maybe have some relationship with the convenient shipping, trade exchanges and optimal environmental conditions, which was also conducive to rice cultivation.

  5. Site Characterization at a Tidal Energy Site in the East River, NY (usa)

    NASA Astrophysics Data System (ADS)

    Gunawan, B.; Neary, V. S.; Colby, J.

    2012-12-01

    A comprehensive tidal energy site characterization is performed using ADV measurements of instantaneous horizontal current magnitude and direction at the planned hub centerline of a tidal turbine over a two month period, and contributes to the growing data base of tidal energy site hydrodynamic conditions. The temporal variation, mean current statistics, and turbulence of the key tidal hydrodynamic parameters are examined in detail, and compared to estimates from two tidal energy sites in Puget Sound. Tidal hydrodynamic conditions, including mean annual current (at hub height), the speed of extreme gusts (instantaneous horizontal currents acting normal to the rotor plane), and turbulence intensity (as proposed here, relative to a mean current of 2 m s-1) can vary greatly among tidal energy sites. Comparison of hydrodynamic conditions measured in the East River tidal straight in New York City with those reported for two tidal energy sites in Puget Sound indicate differences of mean annual current speeds, difference in the instantaneous current speeds of extreme gusts, and differences in turbulence intensities. Significant differences in these parameters among the tidal energy sites, and with the tidal resource assessment map, highlight the importance of conducting site resource characterization with ADV measurements at the machine scale. As with the wind industry, which adopted an International Electrotechnical Commission (IEC) wind class standard to aid in the selection of wind turbines for a particular site, it is recommended that the tidal energy industry adopt an appropriate standard for tidal current classes. Such a standard requires a comprehensive field campaign at multiple tidal energy sites that can identify the key hydrodynamic parameters for tidal current site classification, select a list of tidal energy sites that exhibit the range of hydrodynamic conditions that will be encountered, and adopt consistent measurement practices (standards) for site classification.

  6. Predevelopment Water-Level Contours for Aquifers in the Rainier Mesa and Shoshone Mountain area of the Nevada Test Site, Nye County, Nevada

    SciTech Connect

    Joseph M. Fenelon; Randell J. Laczniak; and Keith J. Halford

    2008-06-24

    Contaminants introduced into the subsurface of the Nevada Test Site at Rainier Mesa and Shoshone Mountain by underground nuclear testing are of concern to the U.S. Department of Energy and regulators responsible for protecting human health and safety. Although contaminants were introduced into low-permeability rocks above the regional flow system, the potential for contaminant movement away from the underground test areas and into the accessible environment is greatest by ground-water transport. The primary hydrologic control on this transport is evaluated and examined through a series of contour maps developed to represent the water-level distribution within each of the major aquifers underlying the area. Aquifers were identified and their extents delineated by merging and analyzing multiple hydrostratigraphic framework models developed by other investigators from existing geologic information. The contoured water-level distribution in each major aquifer was developed from a detailed evaluation and assessment of available water-level measurements. Multiple spreadsheets that accompany this report provide pertinent water-level and geologic data by well or drill hole. Aquifers are mapped, presented, and discussed in general terms as being one of three aquifer types—volcanic aquifer, upper carbonate aquifer, or lower carbonate aquifer. Each of these aquifer types was subdivided and mapped as independent continuous and isolated aquifers, based on the continuity of its component rock. Ground-water flow directions, as related to the transport of test-generated contaminants, were developed from water-level contours and are presented and discussed for each of the continuous aquifers. Contoured water-level altitudes vary across the study area and range from more than 5,000 feet in the volcanic aquifer beneath a recharge area in the northern part of the study area to less than 2,450 feet in the lower carbonate aquifer in the southern part of the study area. Variations in water-level altitudes within any single continuous aquifer range from a few hundred feet in a lower carbonate aquifer to just more than 1,100 feet in a volcanic aquifer. Flow directions throughout the study area are dominantly southward with minor eastward or westward deviations. Primary exceptions are westward flow in the northern part of the volcanic aquifer and eastward flow in the eastern part of the lower carbonate aquifer. Northward flow in the upper and lower carbonate aquifers in the northern part of the study area is possible but cannot be substantiated because data are lacking. Interflow between continuous aquifers is evaluated and mapped to define major flow paths. These flow paths delineate tributary flow systems, which converge to form the regional ground-water flow system. The implications of these tributary flow paths in controlling transport away from the underground test areas at Rainier Mesa and Shoshone Mountain are discussed. The obvious data gaps contributing to uncertainties in the delineation of aquifers and development of water-level contours are identified and evaluated.

  7. Predevelopment Water-Level Contours for Aquifers in the Rainier Mesa and Shoshone Mountain area of the Nevada Test Site, Nye County, Nevada

    USGS Publications Warehouse

    Fenelon, Joseph M.; Laczniak, Randell J.; Halford, Keith J.

    2008-01-01

    Contaminants introduced into the subsurface of the Nevada Test Site at Rainier Mesa and Shoshone Mountain by underground nuclear testing are of concern to the U.S. Department of Energy and regulators responsible for protecting human health and safety. Although contaminants were introduced into low-permeability rocks above the regional flow system, the potential for contaminant movement away from the underground test areas and into the accessible environment is greatest by ground-water transport. The primary hydrologic control on this transport is evaluated and examined through a series of contour maps developed to represent the water-level distribution within each of the major aquifers underlying the area. Aquifers were identified and their extents delineated by merging and analyzing multiple hydrostratigraphic framework models developed by other investigators from existing geologic information. The contoured water-level distribution in each major aquifer was developed from a detailed evaluation and assessment of available water-level measurements. Multiple spreadsheets that accompany this report provide pertinent water-level and geologic data by well or drill hole. Aquifers are mapped, presented, and discussed in general terms as being one of three aquifer types?volcanic aquifer, upper carbonate aquifer, or lower carbonate aquifer. Each of these aquifer types was subdivided and mapped as independent continuous and isolated aquifers, based on the continuity of its component rock. Ground-water flow directions, as related to the transport of test-generated contaminants, were developed from water-level contours and are presented and discussed for each of the continuous aquifers. Contoured water-level altitudes vary across the study area and range from more than 5,000 feet in the volcanic aquifer beneath a recharge area in the northern part of the study area to less than 2,450 feet in the lower carbonate aquifer in the southern part of the study area. Variations in water-level altitudes within any single continuous aquifer range from a few hundred feet in a lower carbonate aquifer to just more than 1,100 feet in a volcanic aquifer. Flow directions throughout the study area are dominantly southward with minor eastward or westward deviations. Primary exceptions are westward flow in the northern part of the volcanic aquifer and eastward flow in the eastern part of the lower carbonate aquifer. Northward flow in the upper and lower carbonate aquifers in the northern part of the study area is possible but cannot be substantiated because data are lacking. Interflow between continuous aquifers is evaluated and mapped to define major flow paths. These flow paths delineate tributary flow systems, which converge to form the regional ground-water flow system. The implications of these tributary flow paths in controlling transport away from the underground test areas at Rainier Mesa and Shoshone Mountain are discussed. The obvious data gaps contributing to uncertainties in the delineation of aquifers and development of water-level contours are identified and evaluated.

  8. The MESA accelerator

    SciTech Connect

    Aulenbacher, Kurt

    2013-11-07

    The MESA accelerator will operate for particle and nuclear physics experiments in two different modes. A first option is conventional c.w. acceleration yielding 150-200MeV spin-polarized external beam. Second, MESA will be operated as a superconducting multi-turn energy recovery linac (ERL), opening the opportunity to perform experiments with a windowless target with beam current of up to 10 mA. The perspectives for innovative experiments with such a machine are discussed together with a sketch of the accelerator physics issues that have to be solved.

  9. 76 FR 30152 - East Calloway County Middle School Mercury Spill Site, Murray, Calloway County, KY; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-24

    ... AGENCY East Calloway County Middle School Mercury Spill Site, Murray, Calloway County, KY; Notice of... response costs concerning the East Calloway County Middle School Mercury Spill Site located in Murray... Site name East Calloway County ] Middle School Mercury Spill Site by one of the following methods:...

  10. Geology in the Vicinity of the TYBO and BENHAM Underground Nuclear Tests, Pahute Mesa, Nevada Test Site

    SciTech Connect

    L. B. Prothro

    2001-12-01

    Recent radiochemical evidence from groundwater characterization and monitoring wells in the vicinity of the TYBO and BENHAM underground nuclear tests in Area 20 of the Nevada Test Site, suggests that migration of radionuclides within groundwater beneath this portion of Area 20 may be more rapid than previously thought. In order to gain a better understanding of the hydrogeologic conditions in the TYBO-BENHAM area for more accurate flow and transport modeling, a reevaluation of the subsurface geologic environment in the vicinity of the two underground tests was conducted. Eight existing drill holes provided subsurface control for the area. These holes included groundwater characterization and monitoring wells, exploratory holes, and large-diameter emplacement holes used for underground nuclear weapons tests. Detailed and consistent geologic descriptions of these holes were produced by updating existing geologic descriptions with data from petrographic, chemical, and mineralogic analyses, and current stratigraphic concepts of the region. The updated descriptions, along with surface geologic data, were used to develop a detailed geologic model of the TYBO-BENHAM area. This model is represented by diagrams that correlate stratigraphic, lithologic, and alteration intervals between holes, and by isopach and structure maps and geologic cross sections. Regional data outside the TYBO-BENHAM area were included in the isopach and structure maps to better evaluate the geology of the TYBO-BENHAM area in a regional context. The geologic model was then evaluated with regard to groundwater flow and radionuclide migration to assess the model's implications for flow and transport modeling. Implications include: (1) confirmation of the general hydrogeology of the area described in previous studies; (2) the presence of two previously unrecognized buried faults that could act as zones of enhanced permeability within aquifers; and (3) secondary alteration within tuff confining units that is much more complex than previously described.

  11. Report of drilling and radionuclide migration investigations at UE20n. number sign. 1, Pahute Mesa, Nevada Test Site, 1987

    SciTech Connect

    Erikson, S.J.

    1991-04-01

    Exploratory hole UE20n{number sign}1 was drilled 305 m down hydraulic gradient of the Cheshire event (U20n) as part of the Radionuclide Migration Program at the Nevada Test Site. The hole was designed to investigate the possibility of groundwater transport of radionuclides from the U20n cavity region. Drilling reached a total depth of 1005.8 m. Composite static water levels in the borehole were measured at approximately 620 m below ground surface. The borehole penetrated about 386 m of saturated zone, which was comprised primarily of rhyolite lava flows of the Upper Rhyolite Lavas, Tuffs, and Rhyolites of Area 20. Evidence from UE20n{number sign}1 suggests the presence of a relatively more permeable zone in the 730 to 750-m depth interval. The neutron log suggests that greater quantities of water were present at depths between 729 and 747 m. Core collected over three depth intervals showed the highest fracture density in a reddish-grey rhyolite lava flow in the 733.8 to 738.1-m core interval. Groundwater flow away from U20n through this permeable zone is suggested by the UE20n{number sign}1 borehole temperature logs. Elevated {sup 3}H activities were observed with the highest activities found near 732 m. The {sup 3}H activities observed in the 732 to 802-m interval in UE20n{number sign}1 were of similar magnitude to those found in the cavity region in the U20n post-shot hole. The activities of {sup 125}Sb and {sup 85}Kr, which are known to be mobile in groundwater, were of similar magnitude to those found near the cavity region, while {sup 137}Cs, which is thought to be adsorbed during transport, was found in activities two to three orders of magnitude lower than near the cavity. These temperature and radioisotope data suggest that radionuclide migration via groundwater flow may be occurring laterally from the U20n rubble chimney through the permeable zone located at the 730 to 750-m depth. 25 refs., 18 figs., 15 tabs.

  12. Surficial Geologic Map of Mesa Verde National Park, Montezuma County, Colorado

    USGS Publications Warehouse

    Carrara, Paul E.

    2012-01-01

    Mesa Verde National Park in southwestern Colorado was established in 1906 to preserve and protect the artifacts and dwelling sites, including the famous cliff dwellings, of the Ancestral Puebloan people who lived in the area from about A.D. 550 to A.D. 1300. In 1978, the United Nations designated the park as a World Heritage Site. The geology of the park played a key role in the lives of these ancient people. For example, the numerous (approximately 600) cliff dwellings are closely associated with the Cliff House Sandstone of Late Cretaceous age, which weathers to form deep alcoves. In addition, the ancient people farmed the thick, red loess (wind-blown dust) deposits on the mesa tops, which because of its particle size distribution has good moisture retention properties. The soil in this loess cover and the seasonal rains allowed these people to grow their crops (corn, beans, and squash) on the broad mesa tops. Today, geology is still an important concern in the Mesa Verde area because the landscape is susceptible to various forms of mass movement (landslides, debris flows, rockfalls), swelling soils, and flash floods that affect the park's archeological sites and its infrastructure (roads, septic systems, utilities, and building sites). The map, which encompasses an area of about 100 mi2 (260 km2), includes all of Mesa Verde National Park, a small part of the Ute Mountain Indian Reservation that borders the park on its southern and western sides, and some Bureau of Land Management and privately owned land to the north and east. Surficial deposits depicted on the map include: artificial fills, alluvium of small ephemeral streams, alluvium deposited by the Mancos River, residual gravel on high mesas, a combination of alluvial and colluvial deposits, fan deposits, colluvial deposits derived from the Menefee Formation, colluvial deposits derived from the Mancos Shale, rockfall deposits, debris flow deposits, earthflow deposits, translational and rotational landslide deposits, rock rubble deposits, and loess. Bedrock units depicted on the map include the Cliff House Sandstone, Menefee Formation, Point Lookout Sandstone, and Mancos Shale all of Late Cretaceous age. In addition, minette dikes, of Oligocene age, found at several locations in the park are depicted on the map. Descriptions, including associated hazards and resources as used by the Ancestral Puebloans, are given for all map units.

  13. 12. Smelter site along Coronado Boulevard, looking east. AZ174(Arizona Copper ...

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

    12. Smelter site along Coronado Boulevard, looking east. AZ-174(Arizona Copper Company Smelter Blower House) near center of photograph. - Clifton Townsite, Confluence of Chase Creek & San Francisco River, Clifton, Greenlee County, AZ

  14. Hospital Web site 'tops' in Louisiana. Hospital PR, marketing group cites East Jefferson General Hospital.

    PubMed

    Rees, Tom

    2002-01-01

    East Jefferson General Hospital in Metairie, La., launched a new Web site in October 2001. Its user-friendly home page offers links to hospital services, medical staff, and employer information. Its jobline is a powerful tool for recruitment. The site was awarded the 2002 Pelican Award for Best Consumer Web site by the Louisiana Society for Hospital Public Relations & Marketing. PMID:12238238

  15. A conceptual model and preliminary estimate of potential tritium migration from the Benham (U-20c) site, Pahute Mesa, Nevada Test Site

    SciTech Connect

    Brikowski, T.; Mahin, G.

    1993-08-01

    U-20c is the site of a large below-water-table nuclear test near the Nevada Test Site boundary. A conceptual model of potential groundwater migration of tritium from U-20c is constructed and quantitatively evaluated in this report. The lower portion of the collapse chimney at Benham is expected to intersect 200 m of permeable rhyolite lava, overlain by similar thicknesses of low-permeability zeolitized bedded tuff, then permeable welded tuff. Vertical groundwater flow through the chimney is predicted to be minimal, horizontal transport should be controlled by the regional groundwater flow. Analytic solutions treating only advective transport indicate 1 to 2 km of tritium movement (95% confidence interval 0.7--2.5 km) within 5 years after test-related pressure-temperature transients have dissipated. This point lies at the axis of a potentiometric surface trough along the west edge of Area 20, Nevada Test Site. Within 25 years, movement is predicted to extend to 3 km (95% confidence interval 2--5 km) approximately to the intersection of the trough and the Nevada Test Site boundary. Considering the effects of radioactive decay, but not dispersion, plume concentration would fall below Safe Drinking Water Act standards by 204 years, at a predicted distance of 11 km (95% confidence interval 7--31 km). This point is located in the eastern portion of the Timber Mountain Caldera moat within the Nellis Air Force Range (military bombing range).

  16. Astronomy Developments and Site Testing in East Africa

    NASA Astrophysics Data System (ADS)

    Buckley, D. A. H.

    2015-04-01

    Two astronomical site testing initiatives are beginning in both Kenya and Ethiopia, with the aim of selecting suitable locations in those countries for initially modest sized (1-2m) optical telescopes. The first project, in Kenya, has to date involved a study of existing meteorological satellite data, from which potential sites have been selected for further studies (see paper by Graham et al. in these proceedings). A similar program of astronomical site testing, including using DIMMs, will begin later in 2014 in the Lalibela region of northern Ethiopia, at three potential sites ranging in altitude from ∼3600 to 4500 m. In parallel to this, the Entoto Observatory and Research Centre (EO), comprising twin 1-m alt-az telescopes, has been established at Mt. Entoto, on the outskirts of Addis Ababa, and science operations are due to begin in early 2015.

  17. Inversion of Gravity Data to Define the Pre-Cenozoic Surface and Regional Structures Possibly Influencing Groundwater Flow in the Rainier Mesa Region, Nye County, Nevada

    USGS Publications Warehouse

    Hildenbrand, Thomas G.; Phelps, Geoffrey A.; Mankinen, Edward A.

    2006-01-01

    A three-dimensional inversion of gravity data from the Rainier Mesa area and surrounding regions reveals a topographically complex pre-Cenozoic basement surface. This model of the depth to pre-Cenozoic basement rocks is intended for use in a 3D hydrogeologic model being constructed for the Rainier Mesa area. Prior to this study, our knowledge of the depth to pre-Cenozoic basement rocks was based on a regional model, applicable to general studies of the greater Nevada Test Site area but inappropriate for higher resolution modeling of ground-water flow across the Rainier Mesa area. The new model incorporates several changes that lead to significant improvements over the previous regional view. First, the addition of constraining wells, encountering old volcanic rocks lying above but near pre-Cenozoic basement, prevents modeled basement from being too shallow. Second, an extensive literature and well data search has led to an increased understanding of the change of rock density with depth in the vicinity of Rainier Mesa. The third, and most important change, relates to the application of several depth-density relationships in the study area instead of a single generalized relationship, thereby improving the overall model fit. In general, the pre-Cenozoic basement surface deepens in the western part of the study area, delineating collapses within the Silent Canyon and Timber Mountain caldera complexes, and shallows in the east in the Eleana Range and Yucca Flat regions, where basement crops out. In the Rainier Mesa study area, basement is generally shallow (< 1 km). The new model identifies previously unrecognized structures within the pre-Cenozoic basement that may influence ground-water flow, such as a shallow basement ridge related to an inferred fault extending northward from Rainier Mesa into Kawich Valley.

  18. Inversion of Gravity Data to Define the Pre-Cenozoic Surface and Regional Structures Possibly Influencing Groundwater Flow in the Rainier Mesa Region, Nye County, Nevada.

    SciTech Connect

    Thomas G. Hildenbrand; Geoffrey A. Phelps; Edward A. Mankinen

    2006-09-21

    A three-dimensional inversion of gravity data from the Rainier Mesa area and surrounding regions reveals a topographically complex pre-Cenozoic basement surface. This model of the depth to pre-Cenozoic basement rocks is intended for use in a 3D hydrogeologic model being constructed for the Rainier Mesa area. Prior to this study, our knowledge of the depth to pre-Cenozoic basement rocks was based on a regional model, applicable to general studies of the greater Nevada Test Site area but inappropriate for higher resolution modeling of ground-water flow across the Rainier Mesa area. The new model incorporates several changes that lead to significant improvements over the previous regional view. First, the addition of constraining wells, encountering old volcanic rocks lying above but near pre-Cenozoic basement, prevents modeled basement from being too shallow. Second, an extensive literature and well data search has led to an increased understanding of the change of rock density with depth in the vicinity of Rainier Mesa. The third, and most important change, relates to the application of several depth-density relationships in the study area instead of a single generalized relationship, thereby improving the overall model fit. In general, the pre-Cenozoic basement surface deepens in the western part of the study area, delineating collapses within the Silent Canyon and Timber Mountain caldera complexes, and shallows in the east in the Eleana Range and Yucca Flat regions, where basement crops out. In the Rainier Mesa study area, basement is generally shallow (< 1 km). The new model identifies previously unrecognized structures within the pre-Cenozoic basement that may influence ground-water flow, such as a shallow basement ridge related to an inferred fault extending northward from Rainier Mesa into Kawich Valley.

  19. 18. Tail race of the Hayden Ditch, looking east toward ...

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

    18. Tail race of the Hayden Ditch, looking east toward the Tempe Bridge and Hayden's Butte, the site of Charles Hayden's vision of the Tempe Canal. This ditch, which formerly supplied the San Francisco Canal, has been out of service since the 1950s. Photographer: Mark Durben, June 1989. Source: SRPA - Tempe Canal, South Side Salt River in Tempe, Mesa & Phoenix, Tempe, Maricopa County, AZ

  20. Modeling Approach/Strategy for Corrective Action Unit 99: Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1, with ROTC-1

    SciTech Connect

    Greg Ruskauff

    2008-06-01

    This document describes an approach for preliminary (Phase I) flow and transport modeling for the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU). This modeling will take place before the planned Phase II round of data collection to better identify the remaining data gaps before the fieldwork begins. Because of the geologic complexity, limited number of borings, and large vertical gradients, there is considerable uncertainty in the conceptual model for flow; thus different conceptual models will be evaluated, in addition to different framework and recharge models. The transport simulations will not be used to formally calculate the Contaminant Boundary at this time. The modeling (Phase II) will occur only after the available data are considered sufficient in scope and quality.

  1. An inventory survey at the site of the proposed Kilauea Middle East Rift Zone (KMERZ), Well Site No. 2

    SciTech Connect

    Kennedy, Joseph

    1991-03-01

    At the request of True Mid Pacific Geothermal, Archaeological Consultants of Hawaii, Inc. has conducted an inventory survey at the site of the proposed Kilauea Middle East Rift Zone (KMERZ), Well Site No.2, TMK: 1-2-10:3. The Principal Investigator was Joseph Kennedy M.A., assisted by Jacob Kaio, Field Supervisor and field crew Mark Borrello B.A., Michael O'Shaughnessy B.A., and Randy Adric. This report supercedes all previous reports submitted to the Historic Presentation Section of the Department of Land and Natural Resources. In addition to 100% surface coverage of the 400 x 400 foot well pad itself, 100% surface coverage of a substantial buffer zone was also completed. This buffer zone was established by the Department of Land and Natural Resources, Historic Preservation personnel and extends 1000 feet east and west of the well site and 500 feet north and south of the well site.

  2. Optimal site selection for a high-resolution ice core record in East Antarctica

    NASA Astrophysics Data System (ADS)

    Vance, Tessa R.; Roberts, Jason L.; Moy, Andrew D.; Curran, Mark A. J.; Tozer, Carly R.; Gallant, Ailie J. E.; Abram, Nerilie J.; van Ommen, Tas D.; Young, Duncan A.; Grima, Cyril; Blankenship, Don D.; Siegert, Martin J.

    2016-03-01

    Ice cores provide some of the best-dated and most comprehensive proxy records, as they yield a vast and growing array of proxy indicators. Selecting a site for ice core drilling is nonetheless challenging, as the assessment of potential new sites needs to consider a variety of factors. Here, we demonstrate a systematic approach to site selection for a new East Antarctic high-resolution ice core record. Specifically, seven criteria are considered: (1) 2000-year-old ice at 300 m depth; (2) above 1000 m elevation; (3) a minimum accumulation rate of 250 mm years-1 IE (ice equivalent); (4) minimal surface reworking to preserve the deposited climate signal; (5) a site with minimal displacement or elevation change in ice at 300 m depth; (6) a strong teleconnection to midlatitude climate; and (7) an appropriately complementary relationship to the existing Law Dome record (a high-resolution record in East Antarctica). Once assessment of these physical characteristics identified promising regions, logistical considerations (for site access and ice core retrieval) were briefly considered. We use Antarctic surface mass balance syntheses, along with ground-truthing of satellite data by airborne radar surveys to produce all-of-Antarctica maps of surface roughness, age at specified depth, elevation and displacement change, and surface air temperature correlations to pinpoint promising locations. We also use the European Centre for Medium-Range Weather Forecast ERA 20th Century reanalysis (ERA-20C) to ensure that a site complementary to the Law Dome record is selected. We find three promising sites in the Indian Ocean sector of East Antarctica in the coastal zone from Enderby Land to the Ingrid Christensen Coast (50-100° E). Although we focus on East Antarctica for a new ice core site, the methodology is more generally applicable, and we include key parameters for all of Antarctica which may be useful for ice core site selection elsewhere and/or for other purposes.

  3. Optimal site selection for a high resolution ice core record in East Antarctica

    NASA Astrophysics Data System (ADS)

    Vance, T.; Roberts, J.; Moy, A.; Curran, M.; Tozer, C.; Gallant, A.; Abram, N.; van Ommen, T.; Young, D.; Grima, C.; Blankenship, D.; Siegert, M.

    2015-11-01

    Ice cores provide some of the best dated and most comprehensive proxy records, as they yield a vast and growing array of proxy indicators. Selecting a site for ice core drilling is nonetheless challenging, as the assessment of potential new sites needs to consider a variety of factors. Here, we demonstrate a systematic approach to site selection for a new East Antarctic high resolution ice core record. Specifically, seven criteria are considered: (1) 2000 year old ice at 300 m depth, (2) above 1000 m elevation, (3) a minimum accumulation rate of 250 mm yr-1 IE, (4) minimal surface re-working to preserve the deposited climate signal, (5) a site with minimal displacement or elevation change of ice at 300 m depth, (6) a strong teleconnection to mid-latitude climate and (7) an appropriately complementary relationship to the existing Law Dome record (a high resolution record in East Antarctica). Once assessment of these physical characteristics identified promising regions, logistical considerations (for site access and ice core retrieval) were briefly considered. We use Antarctic surface mass balance syntheses, along with ground-truthing of satellite data by airborne radar surveys to produce all-of-Antarctica maps of surface roughness, age at specified depth, elevation and displacement change and surface air temperature correlations to pinpoint promising locations. We also use the European Centre for Medium-Range Weather Forecast ERA 20th Century reanalysis (ERA-20C) to ensure a site complementary to the Law Dome record is selected. We find three promising sites in the Indian Ocean sector of East Antarctica in the coastal zone from Enderby Land to the Ingrid Christensen Coast (50-100° E). Although we focus on East Antarctica for a new ice core site, the methodology is more generally applicable and we include key parameters for all of Antarctica which may be useful for ice core site selection elsewhere and/or for other purposes.

  4. Argonne National Laboratory-East site environmental report for calendar year 1995

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1996-09-01

    This report presents the environmental report for the Argonne National Laboratory-East for the year of 1995. Topics discussed include: general description of the site including climatology, geology, seismicity, hydrology, vegetation, endangered species, population, water and land use, and archaeology; compliance summary; environmental program information; environmental nonradiological program information; ground water protection; and radiological monitoring program.

  5. Hydrogeologic setting east of a low-level radioactive-waste disposal site near Sheffield, Illinois

    USGS Publications Warehouse

    Foster, J.B.; Garklavs, George; Mackey, G.W.

    1984-01-01

    Core samples from 45 test wells and 4 borings were used to describe the glacial geology of the area east of the low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Previous work has shown that shallow ground water beneath the disposal site flows east through a pebbly-sand unit of the Toulon Member of the Glasford Formation. The pebbly sand was found in core samples from wells in an area extending northeast from the waste-disposal site to a strip-mine lake and east along the south side of the lake. Other stratigraphic units identified in the study area are correlated with units found on the disposal site. The pebbly-sand unit of the Toulon Member grades from a pebbly sand on site into a coarse gravel with sand and pebbles towards the lake. The Hulick Till Member, a key bed, underlies the Toulon Member throughout most of the study area. A narrow channel-like depression in the Hulick Till is filled with coarse gravelly sand of the Toulon Member. The filled depression extends eastward from near the northeast corner of the waste-disposal site to the strip-mine lake. (USGS)

  6. Ice crystal precipitation at Dome C site (East Antarctica)

    NASA Astrophysics Data System (ADS)

    Santachiara, G.; Belosi, F.; Prodi, F.

    2016-01-01

    For the first time, falling ice crystals were collected on glass slides covered with a thin layer of 2% formvar in chloroform at the Dome Concordia site (Dome C), Antarctica. Samplings were performed in the framework of the 27th Italian Antarctica expedition of the Italian National Program for Research in Antarctica in the period 21 February-6 August 2012. Events of clear-sky precipitations and precipitations from clouds were considered and the replicas obtained were examined under Scanning Electron Microscope (SEM). Several shapes of ice crystals were identified, including "diamond dust" (plates, pyramids, hollow and solid columns), and crystal aggregates varying in complexity. Single events often contained both small (10 μm to 50 μm) and large (hundreds of microns) crystals, suggesting that crystals can form simultaneously near the ground (height of a few hundred metres) and at higher layers (height of thousands of metres). Images of sampled crystal replicas showed that single bullets are not produced separately, but by the disintegration of combinations of bullets. Rimed ice crystals were absent in the Dome C samples, i.e. the only mode of crystal growth was water vapour diffusion. On considering the aerosol in the sampled crystals, we reached the conclusion that inertial impaction, interception and Brownian motion were insufficient to explain the scavenged aerosol. We therefore presume that phoretic forces play a role in scavenging during the crystal growth process.

  7. Assessing hydraulic connections across a complex sequence of volcanic rocks-Analysis of U-20 WW multiple-well aquifer test, Pahute Mesa, Nevada National Security Site, Nevada

    USGS Publications Warehouse

    Garcia, C. Amanda; Fenelon, Joseph M.; Halford, Keith J.; Reiner, Steven R.; Laczniak, Randell J.

    2011-01-01

    Groundwater beneath Pahute Mesa flows through a complexly layered sequence of volcanic rock aquifers and confining units that have been faulted into distinct structural blocks. Hydraulic property estimates of rocks and structures in this flow system are necessary to assess radionuclide migration near underground nuclear testing areas. The U.S. Geological Survey (USGS) used a 12 month (October 1, 2008-October 1, 2009) intermittent pumping schedule of well U-20 WW and continuously monitored water levels in observation wells ER-20-6 #3, UE-20bh 1, and U-20bg as a multi-well aquifer test to evaluate hydraulic connections across structural blocks, bulk hydraulic properties of volcanic rocks, and the hydraulic significance of a major fault. Measured water levels were approximated using synthetic water levels generated from an analytical model. Synthetic water levels are a summation of environmental water-level fluctuations and a Theis (1935) transform of the pumping signal from flow rate to water-level change. Drawdown was estimated by summing residual differences between measured and synthetic water levels and the Theis-transformed pumping signal from April to September 2009. Drawdown estimates were used in a three-dimensional numerical model to estimate hydraulic properties of distinct aquifers, confining units, and a major fault. A maximum water-level drawdown of nearly 0.4 foot in well UE-20bh 1, which is more than 1 mile from the pumping well, was detected across a major fault. Drawdown estimates in the observation well nearest to (ER-20-6 #3, less than 1 mile) and within the same structural block as the pumping well were less than detection (-6 per foot, respectively, and transmissivity estimates range from 1,200 to 3,600 feet squared per day. Sensitivity analyses indicate that the major fault is hydraulically similar to the permeable host rock and connects flow between structural blocks.

  8. Emissions of black carbon in East Asia estimated from observations at a remote site in the East China Sea

    NASA Astrophysics Data System (ADS)

    Kondo, Y.; Oshima, N.; Kajino, M.; Mikami, R.; Moteki, N.; Takegawa, N.; Verma, R. L.; Kajii, Y.; Kato, S.; Takami, A.

    2011-08-01

    East Asia, including China, is the largest source of anthropogenic black carbon (BC). In estimating the BC emissions from this region, it is advantageous to use BC mass concentrations measured at remote locations on the ocean appropriately distant from the large sources because of spatially uniform distributions through mixing during transport. We made continuous measurements of the BC mass concentration with an accuracy of about 10% at Cape Hedo on Okinawa Island, Japan, in the East China Sea, from February 2008 to May 2009, simultaneously with carbon monoxide (CO). The seasonal median BC concentrations at Hedo were highest (0.23-0.31 μg m-3 at standard temperature and pressure) in winter and spring when plumes from China, predominantly northern China north of 33°N, were often transported to the site. A three-dimensional chemical transport model is used to calculate the mass concentration of BC using the annual mean emission inventory of Zhang et al. (2009) for the base year 2006. The model results and the observed BC-CO correlation are used to exclude the BC data substantially influenced by wet deposition. The calculated BC mass concentrations agree with those observed to within about 30% in air strongly affected by emissions in China for winter and spring on average. We estimate the annually averaged BC emission flux over the whole of China to be 1.92 Tg yr-1 with an uncertainty of about 40%. This value is very close to the value of 1.81 Tg yr-1 estimated by Zhang et al. (2009). The overall uncertainty of 40% of the present estimate is a substantial improvement in the uncertainty (208%) of the bottom-up inventory.

  9. Remedial actions at the former Climax Uranium Company, Uranium Mill site, Grand Junction, Mesa County, Colorado. Volume 2, Appendices: Final environmental impact statement

    SciTech Connect

    1986-12-01

    This volume contains Appendix F--hydrology report, and Appendix G--flood plain and wetland assessment. Contents of the hydrology report include: surface water; ground water; potentially affected hydrogeologic environment-processing site; potentially affected hydrogeologic environment-Cheney reservoir site; potentially affected hydrogeologic environment-Two Road site; and conclusions-ground water.

  10. An age for Kajong, a Miocene fossil site east of Lake Turkana, Kenya

    NASA Astrophysics Data System (ADS)

    Brown, Francis H.; Jicha, Brian R.; Leakey, R. E.

    2016-02-01

    The Kajong Formation in Marsabit District, northern Kenya has yielded a Miocene mammalian fauna consisting of nine taxa. It is capped by a basalt 40Ar/39Ar dated at 19.1 ± 0.1 Ma, and a volcanic clast from a conglomerate within the formation yielded an age of 20.3 Ma, only slightly older. The entire fauna from this site thus lies close to the base of the Miocene Epoch and is older than 19.2 Ma. The site has yielded some of the oldest examples of Archaeobelodon filholi, Prodeinotherium hobleyi, and Gomphotherium sp. in east Africa.

  11. Potential long-term chemical effects of diesel fuel emissions on a mining environment: A preliminary assessment based on data from a deep subsurface tunnel at Rainer Mesa, Nevada test site

    SciTech Connect

    Meike, A.; Bourcier, W.L.; Alai, M.

    1995-09-01

    The general purpose of the Yucca Mountain Site Characterization Project (YMSCP) Introduced Materials Task is to understand and predict potential long-term modifications of natural water chemistry related to the construction and operation of a radioactive waste repository that may significantly affect performance of the waste packages. The present study focuses on diesel exhaust. Although chemical information on diesel exhaust exists in the literature, it is either not explicit or incomplete, and none of it establishes mechanisms that might be used to predict long-term behavior. In addition, the data regarding microbially mediated chemical reactions are not well correlated with the abiotic chemical data. To obtain some of the required long-term information, we chose a historical analog: the U12n tunnel at Rainier Mesa, Nevada Test Site. This choice was based on the tunnel`s extended (30-year) history of diesel usage, its geological similarity to Yucca Mountain, and its availability. The sample site within the tunnel was chosen based on visual inspection and on information gathered from miners who were present during tunnel operations. The thick layer of dark deposit at that site was assumed to consist primarily of rock powder and diesel exhaust. Surface samples and core samples were collected with an intent to analyze the deposit and to measure potential migration of chemical components into the rock. X-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy (SEM) with energy dispersive spectra (EDS) analysis, secondary-ion mass spectrometry (SIMS), and Fourier transform infrared (FTIR) analysis were used to measure both spatial distribution and concentration for the wide variety of chemical components that were expected based on our literature survey.

  12. Red Sky with Red Mesa

    ScienceCinema

    None

    2014-06-23

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  13. Career Education at Mesa Verde

    ERIC Educational Resources Information Center

    Triplett, Napoleon B.

    1974-01-01

    A national pilot school for career education, Mesa Verde High School, Sacramento, subscribes to the philosophy that every student will be provided an abundance of career choices at all times whether he is vocationally, technically, or academically bound. A variety of work opportunities on the campus makes the program possible. (AG)

  14. Edge of the Mesa Alta

    USGS researcher Craig Allen stands on the edge of Mesa Alta, amid diverse forest and woodland in the uplands of northern New Mexico; note some recently dead ponderosa pine and Douglas-fir in the field of view. Forest drought stress is strongly correlated with tree mortality from poor growth, bark be...

  15. Red Sky with Red Mesa

    SciTech Connect

    2011-04-14

    The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

  16. Carnotite resources of the Calamity group area, Mesa County, Colorado

    USGS Publications Warehouse

    Stager, Harold K.

    1951-01-01

    The Calamity group area, which includes 28 unpatented Government claims and enclosed fractions of public domain, lies along the east rim of Calamity Mesa, Mesa County, Colo.  From 1915 through 1944, about 10,000 tons of carnotite ore, averaging about 1.0 percent U3O8 and 2.5 percent V2O5, was produced from mines in this group (tons in this report are short tons).  Production from this area from August 1949 to January 1, 1951, totaled 8,100 tons of ore with an average grade of 0.36 percent U3O8 and 1.66 percent V2O5, containing about 58,600 pounds of U3O8 and 268,000 pounds of V2O5.

  17. Seismic design spectra 200 West and East Areas DOE Hanford Site, Washington

    SciTech Connect

    Tallman, A.M.

    1995-12-31

    This document presents equal hazard response spectra for the W236A project for the 200 East and West new high-level waste tanks. The hazard level is based upon WHC-SD-W236A-TI-002, Probabilistic Seismic Hazard Analysis, DOE Hanford Site, Washington. Spectral acceleration amplification is plotted with frequency (Hz) for horizontal and vertical motion and attached to this report. The vertical amplification is based upon the preliminary draft revision of Standard ASCE 4-86. The vertical spectral acceleration is equal to the horizontal at frequencies above 3.3Hz because of near-field, less than 15 km, sources.

  18. Export of Atmospheric Mercury from East Asia Observed at Various Monitoring Sites in Taiwan

    NASA Astrophysics Data System (ADS)

    Sheu, G.; Lin, N.; Wang, J.; Lee, C.; Chang, S.

    2009-12-01

    East Asia is the major atmospheric mercury (Hg) source region in the world due to the excessive coal combustion, industrial emission, and biomass burning in this area. Nonetheless, studies concerning the export of atmospheric Hg from East Asia are still limited. Accordingly, atmospheric Hg has been measured at various sites in Taiwan to study its temporal and spatial distribution, and the significance of long-range transport from the East Asian continent as well. Here we report the data collected in Fu-guei-jiao (121.97°E, 25.47°N, ~30 m a.s.l.), Mt. Bamboo (121.54°E, 25.19°N, 1025 m a.s.l.), and Lulin Atmospheric Background Station (LABS; 120.87°E, 23.47°N, 2862 m a.s.l.) to discuss the atmospheric Hg export from the East Asian continent. Twenty-four hour-integrated total atmospheric Hg (THg) samples were manually collected in Fu-guei-jiao and Mt. Bamboo in 2007-2008 and quantified by dual amalgamation CVAFS. On the other hand, continuous measurements of gaseous elemental Hg (GEM), reactive gaseous Hg (RGM), and particulate Hg (PHg) at LABS began since April 13, 2006 using the Tekran 2537A/1130/1135 speciation system. Mean(±S.D.) THg concentrations were 2.09±0.71 and 1.86±0.50 ng m-3 for Fu-guei-jiao and Mt. Bamboo, respectively. At LABS between April 2006 and April 2009, the mean(±S.D.) concentrations of GEM, RGM and PHg were 1.77±0.54 ng m-3, 22.4±43.8 pg m-3 and 6.3±10.9 pg m-3, respectively. Evident seasonal distribution in THg/GEM concentrations was observed at all sites with higher values usually occurred between fall and spring when the air masses were mainly from the East Asian continent, indicating the influence of the East Asian atmospheric Hg outflow. This also demonstrated that the atmospheric Hg export is occurring both in the boundary layer and in the free troposphere. Concentrations of PHg were usually low at LABS; however, elevated values were detected in spring when the Indochina Peninsula biomass burning plumes frequently affected the sampling site. This PHg enhancement showed the difference between atmospheric Hg emission from biomass burning (Southeast Asia) and from coal burning/industrial activities (China). Unlike the THg/GEM and PHg that exhibited seasonal variation because of the direct influence of the East Asian atmospheric Hg outflow, the source of RGM seemed to be the oxidation of GEM in the free troposphere and thus its seasonality depended primarily on the magnitude of the subsidence of air masses from higher elevation.

  19. Archaeological survey of the 200 East and 200 West Areas, Hanford Site, Washington

    SciTech Connect

    Chatters, J.C.; Cadoret, N.A.

    1990-03-01

    Responding to a heavy demand for cultural resource reviews of excavation sites, the Westinghouse Hanford Company contracted with Pacific Northwest Laboratory to conduct a comprehensive archaeological resource review for the 200 Areas of the Hanford Site, Washington. This was accomplished through literature and records review and an intensive pedestrian survey of all undisturbed portions of the 200 East Area and a stratified random sample of the 200 West Area. The survey, followed the Secretary of the Interior's guidelines for the identification of historic properties. The result of the survey is a model of cultural resource distributions that has been used to create cultural resource zones with differing degrees of sensitivity. 11 refs., 7 figs., 1 tab.

  20. Argonne National Laboratory-East site environmental report for calendar year 1996

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1997-09-01

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL-E) for 1996. To evaluate the effects of ANL-E operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL-E site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides were measured in air, surface water, on-site groundwater, soil, grass, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL-E effluent water were analyzed. External penetrating radiation doses were measured, and the potential for radiation exposure to off-site population groups was estimated. The results of the surveillance program are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL-E, and other) and are compared with applicable environmental quality standards. A US Department of Energy dose calculation methodology, based on International Commission on Radiological Protection recommendations and the CAP-88 version of the EPA-AIRDOSE/RADRISK computer code, is used in this report. The status of ANL-E environmental protection activities with respect to the various laws and regulations that govern waste handling and disposal is discussed. This report also discusses progress being made on environmental corrective actions and restoration projects.

  1. Argonne National Laboratory-East site environmental report for calendar year 2003.

    SciTech Connect

    Golchert, N. W.; Kolzow, R. G.

    2004-08-12

    This report discusses the accomplishments of the environmental protection program at Argonne National Laboratory-East (ANL-E) for calendar year 2003. The status of ANL-E environmental protection activities with respect to compliance with the various laws and regulations is discussed, along with the progress of environmental corrective actions and restoration projects. To evaluate the effects of ANL-E operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL-E site were analyzed and compared with applicable guidelines and standards. A variety of radionuclides were measured in air, surface water, on-site groundwater, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL-E effluent water were analyzed. External penetrating radiation doses were measured, and the potential for radiation exposure to off-site population groups was estimated. Results are interpreted in terms of the origin of the radioactive and chemical substances (i.e., natural, fallout, ANL-E, and other) and are compared with applicable environmental quality standards. A U.S. Department of Energy dose calculation methodology, based on International Commission on Radiological Protection recommendations and the U.S. Environmental Protection Agency's CAP-88 (Clean Air Act Assessment Package-1988) computer code, was used in preparing this report.

  2. Argonne National Laboratory-East site environmental report for calendar year 1998.

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1999-08-26

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL-E) for 1998. To evaluate the effects of ANL-E operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL-E site were analyzed and compared with applicable guidelines and standards. A variety of radionuclides were measured in air, surface water, on-site groundwater, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL-E effluent water were analyzed. External penetrating radiation doses were measured, and the potential for radiation exposure to off-site population groups was estimated. Results are interpreted in terms of the origin of the radioactive and chemical substances (i.e., natural, fallout, ANL-E, and other) and are compared with applicable environmental quality standards. A US Department of Energy dose calculation methodology, based on International Commission on Radiological Protection recommendations and the US Environmental Protection Agency's CAP-88 (Clean Air Act Assessment Package-1988) computer code, was used in preparing this report. The status of ANL-E environmental protection activities with respect to the various laws and regulations that govern waste handling and disposal is discussed, along with the progress of environmental corrective actions and restoration projects.

  3. Evaluation of Cesium, Strontium, and Lead Sorption, Desorption, and Diffusion in Cores from Western Pahute Mesa, Nevada Test Site, based on Macroscopic and Spectroscopic Investigations

    SciTech Connect

    Charalambos Papelis; Wooyong Um

    2003-03-01

    The interaction of radionuclides and other contaminants with minerals and other aquifer materials controls the rate of migration of these contaminants in groundwater. The stronger these interactions, the more a radionuclide will be retarded. Processes such as sorption and diffusion often control the migration of inorganic compounds in aquifers. These processes are often controlled by the nature of the ions of interest, the nature of the aquifer materials, and the specific geochemical conditions. Parameters describing sorption and diffusion of radionuclides and other inorganic ions on aquifer materials are used in transport codes to predict the potential for migration of these contaminants into the accessible environment. Sorption and diffusion studies can reduce the uncertainty of radionuclide transport modeling on the Nevada Test Site (NTS) and other nuclear testing areas.

  4. Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1

    SciTech Connect

    Nathan Bryant

    2008-05-01

    This document presents a summary and framework of available transport data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater transport model. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

  5. Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1

    SciTech Connect

    Nathan Bryant

    2008-05-01

    This document presents a summary and framework of the available hydrologic data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater flow models. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.

  6. Argonne National Laboratory-East site environmental report for calendar year 1992

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1993-05-01

    This report discusses the results of the Environmental Protection Program at Argonne National Laboratory-East (ANL) for 1992. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides was measured in air, surface water, groundwater, soil, grass, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL effluent water were analyzed. External penetrating radiation doses were measured and the potential for radiation exposure to off-site population groups was estimated. The results of the surveillance program are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL, and other) and are compared with applicable environmental quality standards. A US Department of Energy (DOE) dose calculation methodology, based on International Commission on Radiological Protection (ICRP) recommendations and the CAP-88 version of the EPA-AIRDOSE/RADRISK computer code, is used in this report. The status of ANL environmental protection activities with respect to the various laws and regulations which govern waste handling and disposal is discussed.

  7. Argonne National Laboratory-East site environmental report for calendar year 1991

    SciTech Connect

    Golchert, N.W.; Duffy, T.L.; Moos, L.P.

    1992-05-01

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL) for 1991. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides was measured in air, surface water, groundwater, soil, grass, and bottom sediment samples. Chemical constituents in surface water, groundwater, and ANL effluent water were analyzed. External penetrating radiation doses were measured and the potential for radiation exposure to off-site population groups was estimated. Results are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL, and other) and are compared with applicable environmental quality standards. A US Department of Energy (DOE) dose calculation methodology, based on International Commission on Radiological Protection (ICRP) recommendations and the CAP-88 version of the EPA-AIRDOSE/RADRISK computer code, is used in this report. The status of ANL environmental protection activities with respect to the various laws and regulations which govern waste handling and disposal is discussed. This report also discusses progress being made on environmental corrective actions and restoration projects from past activities.

  8. Argonne National Laboratory--East site environmental report for calendar year 1990

    SciTech Connect

    Golchert, N.W.; Duffy, T.L.; Moos, L.P.

    1991-07-01

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL) for 1990. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides was measured in air, surface water, groundwater, soil, grass, bottom sediment, and milk samples. In addition, chemical constituents in surface water, groundwater, and ANL effluent water were analyzed. External penetrating radiation doses were measured and the potential for radiation exposure to off-site population groups was estimated. The results of the surveillance program are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL, and other) and are compared with applicable environmental quality standards. A US Department of Energy (DOE) dose calculation methodology, based on International Commission on Radiological Protection (ICRP) recommendations, is used in this report. The status of ANL environmental protection activities with respect to the various laws and regulations which govern waste handling and disposal is discussed. This report also discusses progress being made on environmental corrective actions and restoration projects from past activities.

  9. Argonne National Laboratory-East site environmental report for calendar year 1994

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1995-05-01

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL) for 1994. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides was measured in air, surface water, groundwater, soil, grass, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL effluent water were analyzed. External penetrating radiation doses were measured and the potential for radiation exposure to off-site population groups was estimated. The results of the surveillance program are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL, and other) and are compared with applicable environmental quality standards. A US Department of Energy (DOE) dose calculation methodology, based on International Commission on Radiological Protection (ICRP) recommendations and the CAP-88 version of the EPA-AIRDOSE/RADRISK COMPUTER CODE, is used in this report. The status of ANL environmental protection activities with respect to the various laws and regulations which govern waste handling and disposal is discussed. This report also discusses progress being made on environmental corrective actions and restoration projects.

  10. Argonne National Laboratory-East site environmental report for calendar year 1993

    SciTech Connect

    Golchert, N.W.; Kolzow, R.G.

    1994-05-01

    This report discusses the results of the environmental protection program at Argonne National Laboratory-East (ANL) for 1993. To evaluate the effects of ANL operations on the environment, samples of environmental media collected on the site, at the site boundary, and off the ANL site were analyzed and compared to applicable guidelines and standards. A variety of radionuclides was measured in air, surface water, groundwater, soil, grass, and bottom sediment samples. In addition, chemical constituents in surface water, groundwater, and ANL effluent water were analyzed. External penetrating radiation doses were measured and the potential for radiation exposure to off-site population groups was estimated. The results of the surveillance program are interpreted in terms of the origin of the radioactive and chemical substances (natural, fallout, ANL, and other) and are compared with applicable environmental quality standards. A US Department of Energy (DOE) dose calculation methodology, based on International Commission on Radiological Protection (ICRP) recommendations and the CAP-88 version of the EPA-AIRDOSE/RADRISK computer code, is used in this report. The status of ANL environmental protection activities with respect to the various laws and regulations which govern waste handling and disposal is discussed. This report also discusses progress being made on environmental corrective actions and restoration projects from past activities.

  11. A Hydrostrat Model and Alternatives for Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainer Mesa-Shoshone Mountain, Nye County, Nevada

    SciTech Connect

    NSTec Geotechnical Sciences Group

    2007-03-01

    The three-dimensional hydrostratigraphic framework model for the Rainier Mesa-Shoshone Mountain Corrective Action Unit was completed in Fiscal Year 2006. The model extends from eastern Pahute Mesa in the north to Mid Valley in the south and centers on the former nuclear testing areas at Rainier Mesa, Aqueduct Mesa, and Shoshone Mountain. The model area also includes an overlap with the existing Underground Test Area Corrective Action Unit models for Yucca Flat and Pahute Mesa. The model area is geologically diverse and includes un-extended yet highly deformed Paleozoic terrain and high volcanic mesas between the Yucca Flat extensional basin on the east and caldera complexes of the Southwestern Nevada Volcanic Field on the west. The area also includes a hydrologic divide between two groundwater sub-basins of the Death Valley regional flow system. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the model area. Three deep characterization wells, a magnetotelluric survey, and reprocessed gravity data were acquired specifically for this modeling initiative. These data and associated interpretive products were integrated using EarthVision{reg_sign} software to develop the three-dimensional hydrostratigraphic framework model. Crucial steps in the model building process included establishing a fault model, developing a hydrostratigraphic scheme, compiling a drill-hole database, and constructing detailed geologic and hydrostratigraphic cross sections and subsurface maps. The more than 100 stratigraphic units in the model area were grouped into 43 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the volcanic units in the model area into 35 hydrostratigraphic units that include 16 aquifers, 12 confining units, 2 composite units (a mixture of aquifer and confining units), and 5 intrusive confining units. The underlying pre-Tertiary rocks are divided into six hydrostratigraphic units, including three aquifers and three confining units. Other units include an alluvial aquifer and a Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units ('layers' in the model). The model also incorporates 56 Tertiary normal faults and 4 Mesozoic thrust faults. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Four of these alternatives were developed so they can be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area Subproject of the Environmental Restoration Project.

  12. ARNOLD MESA ROADLESS AREA, ARIZONA.

    USGS Publications Warehouse

    Wolfe, Edward W.; McColly, Robert A.

    1984-01-01

    Geologic geochemical, and aeromagnetic investigations and a survey of mines and prospects in the Arnold Mesa Roadless Area, Arizona, provide little evidence for the occurrence of mineral or energy resources. Buried Proterozoic basement rocks are possible hosts of porphyry-type copper and massive sulfide deposits but the thick cover of Paleozoic sedimentary rocks and upper Cenozoic volcanic rocks precluded assessment of this possibility. Chemistry and temperature of spring and well waters suggest that a geothermal resource may exist near the eastern margin of the roadless area, but the anomaly has not been tested by drilling and this resource remains unverified. No other energy resources were identified.

  13. Seasonality of the plankton community at an east and west coast monitoring site in Scottish waters

    NASA Astrophysics Data System (ADS)

    Bresnan, Eileen; Cook, Kathryn B.; Hughes, Sarah L.; Hay, Steve J.; Smith, Kerry; Walsham, Pamela; Webster, Lynda

    2015-11-01

    This study presents the first comparative description of the physics, nutrients and plankton communities at two Scottish monitoring sites between 2003 and 2012; Stonehaven on the east coast of Scotland and Loch Ewe on the west coast. This description provides baseline information about the diversity of the plankton community in Scottish waters to support assessment of the plankton community for the EU Marine Strategy Framework Directive. Spring time temperatures at Loch Ewe were approximately 2 °C higher and the median secchi depth was almost 1 m greater than at Stonehaven during this period. Freshwater inflow from the river Ewe may promote water column stability at Loch Ewe. These factors may account for the earlier spring bloom observed at the Loch Ewe monitoring site. The seasonality of chlorophyll 'a' at Loch Ewe was typical of stratified waters in temperate regions with a strong spring/autumn peak attributed to increased numbers of diatoms whilst dinoflagellates dominated during the summer. At Stonehaven highest concentrations of chlorophyll were recorded between May and June and the autumn diatom bloom was considerably less than in Loch Ewe. A higher biomass of zooplankton grazers was found at Loch Ewe than at Stonehaven. Pseudocalanus was the dominant copepod at both sites, particularly during the spring period. Zooplankton carnivores were also more abundant at Loch Ewe than at Stonehaven and were dominated by cnidarians. Considerable interannual variability was observed in cnidarian abundance and diversity at both sites. Variation in the abundance of Ceratium, Calanus finmarchicus and Calanus helgolandicus at both sites followed similar trends in other time series suggesting that the plankton communities at Stonehaven and Loch Ewe are responding to large scale environmental influences.

  14. Phase I Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nevada Test Site, Nye County, Nevada with Errata Sheet 1, 2, 3, Revision 1

    SciTech Connect

    Greg Ruskauff

    2009-02-01

    As prescribed in the Pahute Mesa Corrective Action Investigation Plan (CAIP) (DOE/NV, 1999) and Appendix VI of the Federal Facility Agreement and Consent Order (FFACO) (1996, as amended February 2008), the ultimate goal of transport analysis is to develop stochastic predictions of a contaminant boundary at a specified level of uncertainty. However, because of the significant uncertainty of the model results, the primary goal of this report was modified through mutual agreement between the DOE and the State of Nevada to assess the primary model components that contribute to this uncertainty and to postpone defining the contaminant boundary until additional model refinement is completed. Therefore, the role of this analysis has been to understand the behavior of radionuclide migration in the Pahute Mesa (PM) Corrective Action Unit (CAU) model and to define, both qualitatively and quantitatively, the sensitivity of such behavior to (flow) model conceptualization and (flow and transport) parameterization.

  15. The East Pacific Rise 8° -11° N Integrated Studies Site (ISS); Update and Opportunities

    NASA Astrophysics Data System (ADS)

    Tolstoy, M.; Carbotte, S.; Haymon, R.; Holland, M.; Mullineaux, L.; von Damm, K.

    2004-12-01

    The 8° -11° N segment of the East Pacific Rise (EPR) represents a dynamic, fast-spreading type of mid-ocean ridge selected for focused interdisciplinary study within the Ridge 2000 program. Diverse fast spreading environments are encompassed by the site including a hierarchy of axial segments and discontinuities. The site "bull's- eye" is at 9° 49' - 9° 51' N where numerous high temperature vents and diffuse flow communities have been mapped and monitored over the past 10 years. Concentric circles around the bull's eye encompass ridge segments at a range of scales, from the first-order segment bounded by the Siquieros and Clipperton transform faults to the fourth-order segments which include the extent of the 1991 and 1992 volcanic eruptions. Five-year goals for the site include a working model of mantle flow and melt supply; detailed imaging of subseafloor structures and relationships to vent communities and chemistry; quantitative data about microbes and macrofauna and linkages with fluid flow, tectonics, and magmatism; quantification of the heat flux into the water column; and linkages and temporal variation in geological, chemical, and biological parameters. Field programs at the EPR site in 2004 began with a multi-program cruise lead by Schouten and colleagues that included dives for volcanological objectives, the deployment and testing of an array of in situ chemical sensors for use in monitoring vent fluids (Seyfried), and deployment of sample collection plates for a study of the role of microbes in the weathering of ocean crustal rocks (Edwards and Bach). A magnetotelluric and controlled source electromagnetic study (Constable) was carried out from 9° 30-50'N targeting mantle and crustal structure. The next cruises at this site were the time series fluid sampling program of Von Damm and biological study of Lutz and colleagues, both programs focused at the site "Bull's eye". OBSs deployed in Fall 2003 for a microseismicity monitoring study (Tolstoy and Waldhauser) were recovered and redeployed during the Lutz et al. cruise, and temperature probes were deployedduring the Von Damm cruise. Programs scheduled for 2005 include ongoing monitoring studies of seismicity and vent fauna. Recently funded studies at the EPR site include an investigation of larval dispersal (Mullineaux) and a geodetic study of seafloor motions using pressure sensors deployed along the ridge crest from roughly 9° -10° N (Cormier et al.). A three-dimensional multi-channel seismic study of subsurface structure (Mutter et al.) is scheduled for early 2006. An overview of these and other exciting on-going and upcoming studies within the EPR ISS will be presented.

  16. Completion Report for Well ER-20-4 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2011-04-30

    Well ER-20-4 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada National Security Site, Nye County, Nevada. The well was drilled in August and September 2010 as part of the Pahute Mesa Phase II drilling program. The primary purpose of the well was to investigate the possibility of radionuclide transport from up-gradient underground nuclear tests conducted in central Pahute Mesa. This well also provided detailed hydrogeologic information in the Tertiary volcanic section that will help reduce uncertainties within the Pahute Mesa-Oasis Valley hydrostratigraphic framework model.

  17. Mars EVA Suit Airlock (MESA)

    NASA Astrophysics Data System (ADS)

    Ransom, Stephen; Böttcher, Jörg; Steinsiek, Frank

    The Astrium Space Infrastructure Division has begun an in-house research activity of an Earth-based simulation facility supporting future manned missions to Mars. This research unit will help to prepare and support planned missions in the following ways: 1) to enable the investigation and analysis of contamination issues in advance of a human visit to Mars; 2) as a design tool to investigate and simulate crew operations; 3) to simulate crew operation during an actual mission; 4) to enable on-surface scientific operations without leaving the shirt-sleeve habitation environment ("glove box principle"). The MESA module is a surface EVA facility attached to the main habitation or laboratory module, or mobile pressurized rover. It will be sealed, but not pressurized, and provide protection against the harsh Martian environment. This module will include a second crew airlock for safety reasons. The compartment can also be used to provide an external working bench and experiment area for the crew. A simpler MESA concept provides only an open shelter against wind and dust. This concept does not incorporate working and experimental areas. The principle idea behind the MESA concept is to tackle the issue of contamination by minimizing the decontamination processes needed to clean surface equipment and crew suit surfaces after an EVA excursion prior to the astronaut re-entering the habitable area. The technical solution envisages the use of a dedicated crew suit airlock. This airlock uses an EVA suit which is externally attached by its back-pack to the EVA compartment area facing the Martian environment. The crew donns the suit from inside the habitable volume through the airlock on the back of the suit. The surface EVA can be accomplished after closing the back-pack and detaching the suit. A special technical design concept foresees an extendable suit back-pack, so that the astronaut can operate outside and in the vincinity of the module. The key driver in the investigation is the problem of contamination of the habitable volume by EVA and sampling activities and the transport of Earth-generated contaminants to Mars.

  18. Overview from bluff east of facility. Note buildings #35 (left). ...

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

    Overview from bluff east of facility. Note buildings #35 (left). #33 (center), and #31 A (right) VIEW WEST - Department of Energy, Grand Junction Office, 2597 B3/4 Road, Grand Junction, Mesa County, CO

  19. Observations of ambient monoterpenes at a costal site in the East Mediterranean

    NASA Astrophysics Data System (ADS)

    Tzitzikalaki, Evaggelia; Kalivitis, Nikolaos; Kouvarakis, Giorgos; Kanakidou, Maria; Mihalopoulos, Nikolaos

    2015-04-01

    Observations of ambient monoterpenes at a costal site in the East Mediterranean Biogenic Volatile Organic Compounds (BVOCs) affect the oxidizing capacity of the atmosphere since they react with hydroxyl radicals, nitrate radicals and ozone, and participate in ozone formation in the presence of sufficient amounts of nitrogen oxides. Moreover, BVOC oxidation products contribute to new particle formation and growth processes. While isoprene is emitted in the largest amount among BVOCs into the atmosphere, monoterpenes are also important for atmospheric chemistry. Tree species are responsible of the most BVOC emissions to the atmosphere but little is known about the contribution of shrub and long-range transport to the ambient BVOC concentrations. In the Mediterranean region monoterpene measurements are scarce and are limited in temporal and ecosystem coverage (forested areas). The present study presents long- term measurements of monoterpenes at a remote coastal site without tree vegetation under typical phrygana vegetation of Crete island in Greece. Measurements took place (35° 20' N, 25° 40' E, 250m a.s.l) on the north east side of the island of Crete at the Finokalia monitoring station of the University of Crete (http://finokalia.chemistry.uoc.gr). Two intensive campaigns took place, one during spring (13/03-08/04/2014) and one during summer(19/06 - 04/08/2014). During each campaign diurnal cycles were measured collecting 9 samples per day(every two hours). In addition, one diurnal cycle per week has been measured since 13/10/2014. Off-line sampling took place in adsorption tubes, using stainless steel cartridges filled with Tenax TA for one hour at 200 ml/min flow rate. Samples were stored at 40C and analyzed within two days. The samples were after desorption by a Thermal Desorber were analyzed by a GC-FID system. The most abundant monoterpenes were found to be Δ3-carene and limonene.Highest concentrations were observed during autumn when a clear diurnal cycle has been seen with maximum for both Δ3-carene and limonene at late afternoon. During summer, no clear diurnal variance was observed while in spring the cycle was weaker. The results are analyzed together with new particle formation observations at the Finokalia station to estimate possible links of BVOCs to the formation and growth processes of atmospheric particles in the area.

  20. Deep Radiostratigraphy of the East Antarctic Plateau: Connecting the Dome C and Vostok Ice Core Sites

    NASA Technical Reports Server (NTRS)

    Cavitte, Marie G. P.; Blankenship, Donald D.; Young, Duncan A.; Schroeder, Dustin M.; Parrenin, Frederic; Lemeur, Emmanuel; Macgregor, Joseph A.; Siegert, Martin J.

    2016-01-01

    Several airborne radar-sounding surveys are used to trace internal reflections around the European Project for Ice Coring in Antarctica Dome C and Vostok ice core sites. Thirteen reflections, spanning the last two glacial cycles, are traced within 200 km of Dome C, a promising region for million-year-old ice, using the University of Texas Institute for Geophysics High-Capacity Radar Sounder. This provides a dated stratigraphy to 2318 m depth at Dome C. Reflection age uncertainties are calculated from the radar range precision and signal-to-noise ratio of the internal reflections. The radar stratigraphy matches well with the Multichannel Coherent Radar Depth Sounder (MCoRDS) radar stratigraphy obtained independently. We show that radar sounding enables the extension of ice core ages through the ice sheet with an additional radar-related age uncertainty of approximately 1/3-1/2 that of the ice cores. Reflections are extended along the Byrd-Totten Glacier divide, using University of Texas/Technical University of Denmark and MCoRDS surveys. However, core-to-core connection is impeded by pervasive aeolian terranes, and Lake Vostok's influence on reflection geometry. Poor radar connection of the two ice cores is attributed to these effects and suboptimal survey design in affected areas. We demonstrate that, while ice sheet internal radar reflections are generally isochronal and can be mapped over large distances, careful survey planning is necessary to extend ice core chronologies to distant regions of the East Antarctic ice sheet.

  1. Ages of tuff beds at East African early hominid sites and sediments in the Gulf of Aden

    USGS Publications Warehouse

    Sarna-Wojcicki, A. M.; Meyer, C.E.; Roth, P.H.; Brown, F.H.

    1985-01-01

    The early hominids of East Africa were dated by determining the ages of tuff beds at the sites. Despite much research using palaeomagnetic and K/Ar-dating techniques, some of those ages are still controversial 1,2. To obtain independent age estimates for these tephra layers, we have examined cores from DSDP Sites 231 and 232 in the Gulf of Aden (Fig. 1a) which consist mainly of calcareous nannofossil ooze, but also contain rare tephra horizons3 dated by interpolation from the established nannofossil stratigraphy (Fig. 1b). Chemical analysis confirms that the identity and sequence of these horizons is the same as that at the East African sites. We conclude that the age of the Tulu Bor Tuff is <3.4 Myr and hence that the Hadar hominid specimens are also

  2. Limnology of Blue Mesa, Morrow Point, and Crystal Reservoirs, Curecanti National Recreation area, during 1999, and a 25-year retrospective of nutrient conditions in Blue Mesa Reservoir, Colorado

    USGS Publications Warehouse

    Bauch, Nancy J.; Malick, Matt

    2003-01-01

    The U.S. Geological Survey and the National Park Service conducted a water-quality investigation in Curecanti National Recreation Area in Colorado from April through December 1999. Current (as of 1999) limnological characteristics, including nutrients, phytoplankton, chlorophyll-a, trophic status, and the water quality of stream inflows and reservoir outflows, of Blue Mesa, Morrow Point, and Crystal Reservoirs were assessed, and a 25-year retrospective of nutrient conditions in Blue Mesa Reservoir was conducted. The three reservoirs are in a series on the Gunnison River, with an upstream to downstream order of Blue Mesa, Morrow Point, and Crystal Reservoirs. Physical properties and water-quality samples were collected four times during 1999 from reservoir, inflow, and outflow sites in and around the recreation area. Samples were analyzed for nutrients, phytoplankton and chlorophyll-a (reservoir sites only), and suspended sediment (stream inflows only). Nutrient concentrations in the reservoirs were low; median total nitrogen and phosphorus concentrations were less than 0.4 and 0.06 milligram per liter, respectively. During water-column stratification, samples collected at depth had higher nutrient concentrations than photic-zone samples. Phytoplankton community and density were affected by water temperature, nutrients, and water residence time. Diatoms were the dominant phytoplankton throughout the year in Morrow Point and Crystal Reservoirs and during spring and early winter in Blue Mesa Reservoir. Blue-green algae were dominant in Blue Mesa Reservoir during summer and fall. Phytoplankton density was highest in Blue Mesa Reservoir and lowest in Crystal Reservoir. Longer residence times and warmer temperatures in Blue Mesa Reservoir were favorable for phytoplankton growth and development. Shorter residence times and cooler temperatures in the downstream reservoirs probably limited phytoplankton growth and development. Median chlorophyll-a concentrations were higher in Blue Mesa Reservoir than Morrow Point or Crystal Reservoirs. Blue Mesa Reservoir was mesotrophic in upstream areas and oligotrophic downstream. Both Morrow Point and Crystal Reservoirs were oligotrophic. Trophic-state index values were determined for total phosphorus, chlorophyll-a, and Secchi depth for each reservoir by the Carlson method; all values ranged between 29 and 55. Only the upstream areas in Blue Mesa Reservoir had total phosphorus and chlorophyll-a indices above 50, reflecting mesotrophic conditions. Nutrient inflows to Blue Mesa Reservoir, which were derived primarily from the Gunnison River, varied on a seasonal basis, whereas nutrient inflows to Morrow Point and Crystal Reservoirs, which were derived primarily from deep water releases from the respective upstream reservoir, were steady throughout the sampling period. Total phosphorus concentrations were elevated in many stream inflows. A comparison of current (as of 1999) and historical nutrient, chlorophyll-a, and trophic conditions in Blue Mesa Reservoir and its tributaries indicated that the trophic status in Blue Mesa Reservoir has not changed over the last 25 years, and more recent nutrient enrichment has not occurred.

  3. The Oligocene-Miocene transition at the East Antarctic Wilkes Land margin: IODP Site 1356

    NASA Astrophysics Data System (ADS)

    Salabarnada, Ariadna; Escutia, Carlota; Nelson, Hans; Damuth, John E.; Jimenez-Espejo, Francisco

    2015-04-01

    IODP drilling in the flank of a levee deposit at continental rise Site U1356 recovered a thick section of Oligocene to upper Miocene sediments indicative of relatively deep water, sea ice -- influenced setting. Three main lithological units characterize the sediment record: 1) hemipelagic and bottom current deposition dominated during the late early to late Oligocene; 2) debris flows with interbedded turbidite deposits characterize sedimentation during late Oligocene to early Miocene; and 3) turbidite and hemipelagic sedimentation dominated during the early Miocene. The regional grid of multichannel seismic lines, provide a regional depositional context for the three units. Early to late Oligocene deposits record abyssal plain sedimentation under the influence of bottom currents. The sharp transition from abyssal plain facies to distal debris flows during the late Oligocene coincides with the deposition of large mass transport deposits at the base of the continental slope and erosion of large channels on the continental rise. The distal end of these mass transport deposits is recovered in our cores interbedded with levee turbidites from the nearby channel. The Oligocene to Miocene transition marks the disappearance of debris flows in our cores and the start of turbidite and hemipelagic deposition that characterizes levee sedimentation of the early Miocene environment. The studied section records one of the major climate transitions in the history of Earth's climate and ice sheet evolution during leading to the Mi-1 event. We argue that mass transport processes resulted from East Antarctic Ice Sheet expansion during the climate cooling leading to the Mi-1 glaciation. Following the Mi-1 event, sedimentation is characterized by hemipelagic, turbidity-, and bottom-current deposition. In addition, we present elemental and clay mineralogy data that provide insights into terrigenous fluxes, productivity, and the transition from a poorly oxygenated low-silica system to a ventilated silica-enriched system that is more similar to the modern Southern Ocean.

  4. Seismic Monitoring of the East Pacific Rise Ridge 2000 Integrated Studies Site

    NASA Astrophysics Data System (ADS)

    Tolstoy, M.; Waldhauser, F.

    2003-12-01

    In September 2003 a closely spaced array of twelve ocean bottom seismometers will be deployed within the 'bull's-eye' region of the R2K ISS at 9deg49'N - 9deg51'N on the East Pacific Rise as part of the Ridge 2000 Integrated Studies Site. The array is to be deployed for approximately three years, with annual turn-around cruises. We plan to address a number of fundamental scientific questions, both seismic and interdisciplinary. We expect to study the character of near-axis faulting, to map the seismically active hydrothermal system, to look for tidal triggering of seismicity, and to determine the seismic character of magmatic activity should any be observed. We will make use of the latest advances in earthquake location methodology by computing highly accurate relative locations using the double-difference technique to remove model errors and waveform cross correlation to reduce pick uncertainties. This program is tightly coordinated with the fieldwork of other multidisciplinary monitoring in the area, which will provide an unprecedented opportunity to understand mid-ocean ridge system linkages. We hope to help document links between the seismicity, the hydrothermal system and the associated biology and provide a rigorous understanding of the significance of seismic activity to the mid-ocean ridge system. We will present a detailed outline of the experiment plans, as well as our plans to integrate and share the data collected. Details will also be presented of the deployment cruise including imaging of the 9deg50'N area.

  5. Forest conditions in the Black Mesa Forest Reserve, Arizona

    USGS Publications Warehouse

    Plummer, F.G.; Rixon, T.F.; Dodwell, Arthur

    1904-01-01

    The Black Mesa Forest Reserve, in Arizona, was created by proclamation of President McKinley dated August 17, 1898. The following are its boundaries; "Beginning at a point on the boundary line between Arizona and New Mexico where it is intersected by the north line of township seven (7) north, range thirty-one (31) east, Gila and Salt River meridian, Arizona; thence westerly along the township line to the southeast corner of township eight (8) north, range twenty-seven (27) east; thence northerly to the northeast corner of said township; thence westerly along the second (2nd) standard parallel north to the southeast corner of township nine (9) north, range twenty-six (26) east; thence northerly to the northeast corner of said township; thence westerly along the township line to the southeast corner of township ten (10) north, range twenty-two (22) east; thence northerly to the northeast corner of said township; thence westerly along the township line to the southeast corner of township eleven (11) north, range nineteen (19) east; thence northerly.along the range line to its point of intersection with the forty miles limit of the grant to the Atlantic and Pacific Railroad Company; thence westerly following the forty miles limit of said grant to its intersection with the range line between ranges five (5) and six (6) east, in township fifteen (15) north; thence southerly to the southwest corner of said township; thence easterly along the township line to the northwest corner of township fourteen (14) north, range seven (7) east; thence southerly along the range line to the southwest corner of township thirteen (13) north, range seven (7) east; thence easterly along the third (3rd) standard parallel north to the northwest corner of township twelve (12) north, range eight (8) east; thence southerly to the south- west corner of said township; thence easterly along the township line to the north- west corner of township eleven (11) north, range twelve (12) east; thence southerly to the southwest corner of said township; thence easterly to the northwest corner of the White Mountain Indian Reservation; thence in a general easterly, southeasterly, and southerly direction along the northern and eastern boundaries of said reservation to its intersection with the Gila and Salt River base line; thence easterly along said base line to its intersection with the boundary line between Arizona and New Mexico; thence northerly along said boundary line to the point where it intersects the north line of township seven (7) north, range thirty-one (31) east, the place of beginning."

  6. Transportation of the MOAB Uranium Mill Tailings to White Mesa Mill by Slurry Pipeline

    SciTech Connect

    Hochstein, R. F.; Warner, R.; Wetz, T. V.

    2003-02-26

    The Moab uranium mill tailings pile, located at the former Atlas Minerals Corporation site approximately three miles north of Moab, Utah, is now under the control of the US Department of Energy (''DOE''). The location of the tailings pile adjacent to the Colorado River, and the ongoing contamination of groundwater and seepage of pollutants into the river, have lead to the investigation, as part of the final site remediation program, of alternatives to relocate the tailings to a qualified permanent disposal site. This paper will describe the approach being taken by the team formed between International Uranium (USA) Corporation (''IUC'') and Washington Group International (''WGINT'') to develop an innovative technical proposal to relocate the Moab tailings to IUC's White Mesa Mill south of Blanding, Utah. The proposed approach for relocating the tailings involves using a slurry pipeline to transport the tailings to the White Mesa Mill. The White Mesa Mill is a fully licensed, active uranium mill site that is uniquely suited for permanent disposal of the Moab tailings. The tailings slurry would be dewatered at the White Mesa Mill, the slurry water would be recycled to the Moab site for reuse in slurry makeup, and the ''dry'' tailings would be permanently disposed of in an approved below grade cell at the mill site.

  7. Prediction of Pseudo relative velocity response spectra at Yucca Mountain for underground nuclear explosions conducted in the Pahute Mesa testing area at the Nevada testing site; Yucca Mountain Site Characterization Project

    SciTech Connect

    Phillips, J.S.

    1991-12-01

    The Yucca Mountain Site Characterization Project (YMP), managed by the Office of Geologic Disposal of the Office of Civilian Radioactive Waste Management of the US Department of Energy, is examining the feasibility of siting a repository for commercial, high-level nuclear wastes at Yucca Mountain on and adjacent to the Nevada Test Site (NTS). This work, intended to extend our understanding of the ground motion at Yucca Mountain resulting from testing of nuclear weapons on the NTS, was funded by the Yucca Mountain project and the Military Applications Weapons Test Program. This report summarizes one aspect of the weapons test seismic investigations conducted in FY88. Pseudo relative velocity response spectra (PSRV) have been calculated for a large body of surface ground motions generated by underground nuclear explosions. These spectra have been analyzed and fit using multiple linear regression techniques to develop a credible prediction technique for surface PSRVs. In addition, a technique for estimating downhole PSRVs at specific stations is included. A data summary, data analysis, prediction development, prediction evaluation, software summary and FORTRAN listing of the prediction technique are included in this report.

  8. Estimation of Groundwater Recharge at Pahute Mesa using the Chloride Mass-Balance Method

    SciTech Connect

    Cooper, Clay A; Hershey, Ronald L; Healey, John M; Lyles, Brad F

    2013-07-01

    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 for 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.

  9. YUCCA MOUNTAIN SITE CHARACTERIZATION PROJECT EAST-WEST DRIFT SYSTEM SAFETY ANALYSIS

    SciTech Connect

    NA

    1999-06-08

    The purpose of this analysis is to systematically identify and evaluate hazards related to the design of the Yucca Mountain Project Exploratory Studies Facility (ESF) East-West Cross Drift. This analysis builds upon prior ESF System Safety Analyses and incorporates TS Main Drift scenarios, where applicable, into the East-West Drift scenarios. This System Safety Analysis (SSA) focuses on the personnel safety and health hazards associated with the engineered design of the East-West Drift. The analysis also evaluates other aspects of the East-West Drift, including purchased equipment (e.g., scientific mapping platform) or Systems/Structures/Components (SSCs) and out-of-tolerance conditions. In addition to recommending design mitigation features, the analysis identifies the potential need for procedures, training, or Job Safety Analyses (JSAs). The inclusion of this information in the SSA is intended to assist the organization(s) (e.g., constructor, Safety and Health, design) responsible for these aspects of the East-West Drift in evaluating personnel hazards and augment the information developed by these organizations. The SSA is an integral part of the systems engineering process, whereby safety is considered during planning, design, testing, and construction. A largely qualitative approach is used which incorporates operating experiences and recommendations from vendors, the constructor and the operating contractor. The risk assessment in this analysis characterizes the scenarios associated with East-West Drift SSCs in terms of relative risk and includes recommendations for mitigating all identified hazards. The priority for recommending and implementing mitigation control features is: (1) Incorporate measures to reduce risks and hazards into SSC designs. (2) Add safety features and capabilities to existing designs. (3) Develop procedures and conduct training to increase worker awareness of potential hazards, reduce exposure to hazards, and inform personnel of the actions required to avoid accidents or correct hazardous conditions. This analysis does not consider temporary construction items and, therefore, does not consider hazards associated with temporary construction items. This analysis will be reviewed and updated to reflect new East-West Drift design changes, construction modifications, and ''as built'' documentation of the East-West Drift when completed. A major difference between this analysis and previous ESF SSAs is the inclusion of hazards that arise as a result of non-accident events, (e.g., ''off-normal'' operations, adverse environmental conditions, or ''out-of-tolerance'' conditions). Non-accident events, that were not included in previous ESF SSAs, include environmental and/or toxic hazards such as leaking gases/fluids, off-gassing reactions, and excessive dust, particulates, exhaust fumes, noise, temperature, etc. which could have an adverse health effect on personnel.

  10. Perspectives for Dark Photon physics at MESA

    NASA Astrophysics Data System (ADS)

    Denig, Achim

    2015-04-01

    At the Institute of Nuclear Physics in Mainz the new high-intensity electron accelerator MESA (Mainz Energy-Recovering Superconducting Accelerator) is currently being constructed. We report on opportunities regarding Dark Photon physics at this facility. The intensive MESA beam of 155 MeV and 1 mA of beam current in combination with an internal gas target offers a unique and clean environment for electron scattering experiments. We also report on the status of the MAGIX dual-arm spectrometer setup, which can be used for those measurements. Furthermore, we also comment on opportunities for a beam dump experiment at MESA, which would search for dark matter particles directly. This work is supported by DFG through Collaborative Research Center CRC-1044.

  11. 9. Tempe Canal, Section 17 (TIN, R5E), looking east towards ...

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

    9. Tempe Canal, Section 17 (TIN, R5E), looking east towards the mesa. This is the oldest part of the canal still in use. Photographer: Mark Durben, June 1989. Source: SRPA - Tempe Canal, South Side Salt River in Tempe, Mesa & Phoenix, Tempe, Maricopa County, AZ

  12. Characteristics of soils in selected maize growing sites along altitudinal gradients in East African highlands

    PubMed Central

    Njuguna, Elijah; Gathara, Mary; Nadir, Stanley; Mwalusepo, Sizah; Williamson, David; Mathé, Pierre-Etienne; Kimani, Jackson; Landmann, Tobias; Juma, Gerald; Ong’amo, George; Gatebe, Erastus; Ru, Bruno Le; Calatayud, Paul-andré

    2015-01-01

    Maize is the main staple crop in the East African Mountains. Understanding how the edaphic characteristics change along altitudinal gradients is important for maximizing maize production in East African Highlands, which are the key maize production areas in the region. This study evaluated and compared the levels of some macro and micro-elements (Al, Ca, Fe, K, Mg, Mn, Na and P) and other soil parameters (pH, organic carbon content, soil texture [i.e. % Sand, % Clay and % Silt], cation exchange capacity [CEC], electric conductivity [EC], and water holding capacity [HC]). Soil samples were taken from maize plots along three altitudinal gradients in East African highlands (namely Machakos Hills, Taita Hills and Mount Kilimanjaro) characterized by graded changes in climatic conditions. For all transects, pH, Ca, K and Mg decreased with the increase in altitude. In contrast, % Silt, organic carbon content, Al and water holding capacity (HC) increased with increasing altitude. The research provides information on the status of the physical–chemical characteristics of soils along three altitudinal ranges of East African Highlands and includes data available for further research. PMID:26509187

  13. Revised Hydrogeology for the Suprabasalt Aquifer System, 200-East Area and Vicinity, Hanford Site, Washington

    SciTech Connect

    Williams, Bruce A.; Bjornstad, Bruce N.; Schalla, Ronald; Webber, William D.

    2000-04-20

    This study supports the Hanford Groundwater/Vadose integration project objectives to better understand the risk of groundwater contamination and potential risk to the public via groundwater flow paths. The primary objective of this study was to refine the conceptual groundwater flow model for the 200-East Area and vicinity.

  14. Assessment of the spatio-temporal distribution of soil properties in East Kolkata wetland ecosystem (A Ramsar site: 1208)

    NASA Astrophysics Data System (ADS)

    Pal, S.; Manna, S.; Aich, A.; Chattopadhyay, B.; Mukhopadhyay, S. K.

    2014-06-01

    The present investigation was made to characterize spatial and temporal variations in soil properties and to evaluate possible differences that could be dependent on the tannery effluent discharges, municipal sewage discharges, vegetation cover, soil settlement rate, crop rotation, etc. Soil total organic matter (TOM), cations like, Sodium (Na), Ammonium (NH4), Potassium (K), Calcium (Ca) and Magnesium (Mg) contents in the bank soils and bottom sediments were recorded from seven different characteristic sites in East Kolkata wetland ecosystem, a Ramsar site (Ramsar site No. 1208). The profile maps were constructed by geostatistical methods to describe the spatial distribution as well as temporal variations of all the factors to identify the influences of composite wastewaters. The work was initiated to identify causes and consequences of the waste dumping in the concerned region for the past hundred years and thereby to suggest necessary precautionary measures to prevent further loss of soil quality.

  15. Storm Flow and Sediment Losses From Site-Prepared Forestland in East Texas

    NASA Astrophysics Data System (ADS)

    Blackburn, W. H.; Wood, J. C.; Dehaven, M. G.

    1986-05-01

    Nine small (2.57 to 2.79 ha) forested watersheds in East Texas were instrumented in December 1979 to determine the effect of harvesting and site preparation on storm flow and sediment loss. Three replications of three treatments were used: (1) clearcutting, followed by shearing, windrowing, and burning, (2) clearcutting, followed by roller chopping and burning, and (3) undisturbed control. Prior to treatment, mineral soil was exposed on 3% of the watersheds. Following treatment in June 1981, 57% of the mineral soil was exposed on the sheared and windrowed watersheds compared to 16% on the chopped watersheds. At the end of the second, third, and fourth years' growing season, mineral soil was exposed on 20, 9, and 10% of the sheared and 4, 4, and 3% of the chopped watersheds, respectively. The first year following treatment, mean storm flow was greater from the sheared watersheds (14.6 cm) than from the chopped (8.3 cm) watersheds, with the storm flow from the latter greater than from the undisturbed (2.6 cm) watersheds. Mean storm flow was less from all watersheds the second year after treatment; however, storm flow from the sheared watersheds (5.0 cm) was similar to that from the chopped (3.6 cm) water-sheds, and both were greater than that from the undisturbed (1.2 cm) watersheds. During the third posttreatment year there was no significant difference in mean storm flow from the sheared and chopped watersheds or from chopped and undisturbed watersheds. Storm flow during the fourth posttreatment year was greater from the sheared watersheds (6.1 cm) than from the chopped (3.5 cm) watersheds, which had greater stormflow than the undisturbed (1.4 cm) watersheds. First-year sediment losses were greater from the sheared (2937 kg/ha) than from the chopped (25 kg/ha) or undisturbed (33 kg/ha) watersheds. Although second-year sediment losses were greatly reduced from the sheared watersheds (79.9 kg/ha), they remained greater than losses from chopped (5.5 kg/ha) or undisturbed (5.1 kg/ha) watersheds. Sediment losses from the sheared watersheds (34.6 kg/ha) decreased during the third posttreatment year and were similar to losses from the chopped (5.4 kg/ha) watersheds. During the fourth posttreatment year, sediment loss was greater from the sheared watersheds (165 kg/ha) than from the chopped (16 kg^sol;ha) or the undisturbed (29 kg/ha) watersheds. Although sediment losses were significantly different between treatment,, they were small and below Soil Conservation Service tolerable levels. Mean sediment concentrations and losses from the chopped and undisturbed watersheds were similar during the four posttreatment years. Sediment concentrations from the sheared watersheds, were greater than from chopped or pndisturbed watersheds during the four posttreatment years; however, concentrations the first year after treatment (2119 mg/L) were greatly reduced the second (167 mg/L), third (54 mg/L), and fourth year (331 mg/L).

  16. Geoacoustic model at the DH-1 long-core site in the Korean continental margin of the East Sea

    NASA Astrophysics Data System (ADS)

    Ryang, Woo Hun; Kim, Seong Pil

    2014-05-01

    A long core of 23.6 m was acquired at the DH-1 site (3736.651'N and 12919.709'E) in the Korean continental margin of the western East Sea. The core site is located near the Donghae City and the water depth is 357.8 m deep. The long-core sediment was recovered using the Portable Remotely Operated Drill (PROD), a fully contained drilling system, remotely operated at the seafloor. The recovered core sediments were analyzed for physical, sedimentological, and geoacoustic properties mostly at 10~30 cm intervals. Based on the long-core data with subbottom and air-gun profiles at the DH-1 core site, a geoacoustic model was firstly reconstructed including water mass. The geoacoustic model comprises 7 geoacoustic units of the core sediments, based on the measurements of 125 P-wave velocities and 121 attenuations. The P-wave speed was compensated to in situ depth below the sea floor using the Hamilton method. The geoacoustic model DH-1 probably contributes for reconstruction of geoacoustic models reflecting vertical and lateral variability of acoustic properties in the Korean continental margin of the western East Sea. Keywords: long core, geoacoustic model, East Sea, continental margin, P-wave speed Acknowledgements: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0025733) and by the Ministry of Knowledge Economy through the grant of Marine Geology and Geophysical Mapping Project (GP2010-013).

  17. "Where to Put it? The East-West Split over the site for the 200-inch telescope"

    NASA Astrophysics Data System (ADS)

    Devorkin, D. H.

    1998-05-01

    Hale obtained the funding for his 200-inch telescope at a time when the sciences in America were trying to develop a National Research Fund through the National Academy of Sciences. His successes, and the failure of the Fund, created tensions, especially among prominent East Coast astronomers who themselves had been courting the Rockefeller International Education Board to support the development of southern hemisphere sites. This paper will explore facets of the controversy that will illuminate how Hale's plan was regarded by other astronomers, and how the dispute was finally settled by Henry Norris Russell.

  18. Source identification and apportionment of halogenated compounds observed at a remote site in East Asia.

    PubMed

    Li, Shanlan; Kim, Jooil; Park, Sunyoung; Kim, Seung-Kyu; Park, Mi-Kyung; Mühle, Jens; Lee, Gangwoong; Lee, Meehye; Jo, Chun Ok; Kim, Kyung-Ryul

    2014-01-01

    The sources of halogenated compounds in East Asia associated with stratospheric ozone depletion and climate change are relatively poorly understood. High-precision in situ measurements of 18 halogenated compounds and carbonyl sulfide (COS) made at Gosan, Jeju Island, Korea, from November 2007 to December 2011 were analyzed by a positive matrix factorization (PMF). Seven major industrial sources were identified from the enhanced concentrations of halogenated compounds observed at Gosan and corresponding concentration-based source contributions were also suggested: primary aluminum production explaining 37% of total concentration enhancements, solvent usage of which source apportionment is 25%, fugitive emissions from HCFC/HFC production with 11%, refrigerant replacements (9%), semiconductor/electronics industry (9%), foam blowing agents (6%), and fumigation (3%). Statistical trajectory analysis was applied to specify the potential emission regions for seven sources using back trajectories. Primary aluminum production, solvent usage and fugitive emission sources were mainly contributed by China. Semiconductor/electronics sources were dominantly located in Korea. Refrigerant replacement, fumigation and foam blowing agent sources were spread throughout East Asian countries. The specified potential source regions are consistent with country-based consumptions and emission patterns, verifying the PMF analysis results. The industry-based emission sources of halogenated compounds identified in this study help improve our understanding of the East Asian countries' industrial contributions to halogenated compound emissions. PMID:24298975

  19. Archaeological investigations on the Buckboard Mesa Road Project

    SciTech Connect

    Amick, D.S.; Henton, G.H.; Pippin, L.C.

    1991-10-01

    In 1986, the Desert Research Institute (DRI) conducted an archaeological reconnaissance of a new alignment for the Buckboard Mesa Road on the Nevada Test Site for the Department of Energy (DOE). During this reconnaissance, several archaeological sites of National Register quality were discovered and recorded including a large quarry, site 26Ny4892, and a smaller lithic scatter, site 26Ny4894. Analysis of the debitage at 26Ny4892 indicates that this area was used primarily as a quarry for relatively small cobbles of obsidian found in the alluvium. Lithic reduction techniques used here are designed for efficiently reducing small pieces of toolstone and are oriented towards producing flake blanks from small cores and bifacially reducing exhausted cores. Projectile point cross references indicate that the area has seen at least casual use for about 10,000 years and more sustained use for the last 3,000 years. Initial obsidian hydration measurements indicate sustained use of the quarry for about the last 3,000 years although the loci of activities appear to change over time. Based on this study, the DRI recommends that quarrying activities in the area of 26Ny4892 are sufficiently sampled and that additional investigations into that aspect of prehistoric activity in the area are not necessary. This does not apply to other aspects of prehistoric use. DRI recommends that preconstruction surveys continue to identify nonquarrying, prehistoric utilization of the area. With the increased traffic on the Buckboard Mesa Road, there is a greater potential for vandalism to sites of National Register-quality located near the road. The DRI recommends that during the orientation briefing the workers at the Test Site be educated about the importance of cultural resources and the need for their protection. 202 refs., 41 figs., 52 tabs.

  20. USGS Researcher at Mesa Alta, New Mexico

    USGS researcher Craig Allen stands on the edge of Mesa Alta, amid diverse forest and woodland in the uplands of northern New Mexico; note some recently dead ponderosa pine and Douglas-fir in the field of view. Forest drought stress is strongly correlated with tree mortality from poor growth, bark be...

  1. Career Spanish at Mesa State College.

    ERIC Educational Resources Information Center

    Pilkenton, David

    The development and results of Career Spanish instruction at Mesa State College in Colorado from 1975 to 1991 are described. The class is an individualized, career-oriented class for students who have only 3 to 6 semester hours available for foreign language study and an interest in particular vocational applications of Spanish. With no…

  2. High-frequency constricted mesa lasers

    SciTech Connect

    Bowers, J.E.; Hemenway, B.R.; Gnauck, A.H.; Bridges, T.J.; Burkhardt, E.G.; Wilt, D.P.; Maynard, S.

    1985-07-15

    InGaAsP cw constricted mesa lasers at 1.3 ..mu..m are described which have a small-signal 3-dB bandwidth of 20 GHz at -70 /sup 0/C. Large-signal pseudorandom modulation at 8 Gb/s resulted in 100% optical modulation. The lasers were gain switched at 12 GHz with 100% optical modulation.

  3. Career Spanish at Mesa State College.

    ERIC Educational Resources Information Center

    Pilkenton, David

    The development and results of Career Spanish instruction at Mesa State College in Colorado from 1975 to 1991 are described. The class is an individualized, career-oriented class for students who have only 3 to 6 semester hours available for foreign language study and an interest in particular vocational applications of Spanish. With no

  4. Tidal energy site resource assessment in the East River tidal strait, near Roosevelt Island, New York, New York

    DOE PAGESBeta

    Gunawan, Budi; Neary, Vincent S.; Colby, Jonathan

    2014-06-22

    This study demonstrates a site resource assessment to examine the temporal variation of the mean current, turbulence intensities, and power densities for a tidal energy site in the East River tidal strait. These variables were derived from two-months of acoustic Doppler velocimeter (ADV) measurements at the design hub height of the Verdant Power Gen5 hydrokinetic turbine. The study site is a tidal strait that exhibits semi-diurnal tidal current characteristics, with a mean horizontal current speed of 1.4 m s-1, and turbulence intensity of 15% at a reference mean current of 2 m s-1. Flood and ebb flow directions are nearlymore » bi-directional, with higher current magnitude during flood tide, which skews the power production towards the flood tide period. The tidal hydrodynamics at the site are highly regular, as indicated by the tidal current time series that resembles a sinusoidal function. This study also shows that the theoretical force and power densities derived from the current measurements can significantly be influenced by the length of the time window used for averaging the current data. Furthermore, the theoretical power density at the site, derived from the current measurements, is one order of magnitude greater than that reported in the U.S. national resource assessment. As a result, this discrepancy highlights the importance of conducting site resource assessments based on measurements at the tidal energy converter device scale.« less

  5. Tidal energy site resource assessment in the East River tidal strait, near Roosevelt Island, New York, New York

    SciTech Connect

    Gunawan, Budi; Neary, Vincent S.; Colby, Jonathan

    2014-06-22

    This study demonstrates a site resource assessment to examine the temporal variation of the mean current, turbulence intensities, and power densities for a tidal energy site in the East River tidal strait. These variables were derived from two-months of acoustic Doppler velocimeter (ADV) measurements at the design hub height of the Verdant Power Gen5 hydrokinetic turbine. The study site is a tidal strait that exhibits semi-diurnal tidal current characteristics, with a mean horizontal current speed of 1.4 m s-1, and turbulence intensity of 15% at a reference mean current of 2 m s-1. Flood and ebb flow directions are nearly bi-directional, with higher current magnitude during flood tide, which skews the power production towards the flood tide period. The tidal hydrodynamics at the site are highly regular, as indicated by the tidal current time series that resembles a sinusoidal function. This study also shows that the theoretical force and power densities derived from the current measurements can significantly be influenced by the length of the time window used for averaging the current data. Furthermore, the theoretical power density at the site, derived from the current measurements, is one order of magnitude greater than that reported in the U.S. national resource assessment. As a result, this discrepancy highlights the importance of conducting site resource assessments based on measurements at the tidal energy converter device scale.

  6. Geophysical investigations at Pahute Mesa, Nevada. Final report, 17 Feb 89-21 Nov 91

    SciTech Connect

    Ferguson, J.F.

    1992-04-30

    Part 1 of this study has concentrated on the assembly of a data base of geological and geophysical data for a transect at Pahute Mesa, Nevada. Existing data, in the form of well logs, gravity observations and seismic travel times, have been supplemented by new gravity and seismic data especially for the construction of a geophysical model of the shallow crust. The transect is modeled as an extension basin, with up to 5 km of structural relief and volcanic fill. Major faulting is on the east side. The second part of this study has applied the new GPS technology to geogetic monitoring of nuclear explosions at Pahute Mesa, Nevada. Significant deformation is observed to be caused by the test BULLION. New rapid survey methods have been successfully applied to perform studies, which would have been otherwise prohibitively time consuming.

  7. Revisiting sites of the South Pole Queen Maud Land Traverses in East Antarctica: Accumulation data from shallow firn cores

    NASA Astrophysics Data System (ADS)

    Anschütz, H.; Müller, K.; Isaksson, E.; McConnell, J. R.; Fischer, H.; Miller, H.; Albert, M.; Winther, J.-G.

    2009-12-01

    Ground-based accumulation measurements are scarce on the high East Antarctic plateau, but highly necessary for model validation and the interpretation of satellite data for the determination of Antarctic mass balance. Here, we present accumulation results obtained from four shallow firn cores drilled in the Antarctic summer season 2007/2008. The cores were drilled along the first leg of the Norwegian-US IPY traverse through East Antarctica, visiting sites like Plateau Station and Pole of Relative Inaccessibility that have been covered by the South Pole Queen Maud Land Traverses (SPQMLT) in the 1960s. Accumulation has been determined from volcanic chronology established from the conductivity records measured by dielectric profiling (DEP). The Tambora 1815/unknown 1809 double peak is clearly visible in the conductivity data and serves as a reliable time marker. Accumulation rates averaged over the period 1815-2007 are in the range of 16 to 32 kg m-2 a-1, somewhat lower than expected from the SPQMLT data. The spatial pattern is mainly influenced by elevation and continentality. Three of the firn cores show a decrease of more than 20% in accumulation for the time period 1815-2007 in relation to accumulation rates during the period 1641-1815. The spatial representativity of the firn cores is assessed by ground-penetrating radar, showing a rather smoothly layered pattern around the drill sites. Validation of the DEP results is utilized by comparison with chemistry data, proving the validity of the DEP method for dating firn cores. The results help understanding the status of the East Antarctic ice sheet and will be important for e.g. future model-derived estimates of the mass balance of Antarctica.

  8. Year-round record of surface ozone at coastal (Dumont d'Urville) and inland (Concordia) sites in East Antarctica

    NASA Astrophysics Data System (ADS)

    Legrand, M.; Preunkert, S.; Jourdain, B.; GalléE, H.; Goutail, F.; Weller, R.; Savarino, J.

    2009-10-01

    Surface ozone is measured since 2004 at the coastal East Antarctic station of Dumont d'Urville (DDU) and since 2007 at the Concordia station located on the high East Antarctic plateau. Ozone levels at Concordia reach a maximum of 35 ppbv in July and a minimum of 21 ppbv in February. From November to January, sudden increases of the ozone level, up to 15-20 ppbv above average, often take place. They are attributed to local photochemical ozone production as previously seen at the South Pole. The detailed examination of the diurnal ozone record in summer at Concordia suggests a local photochemical ozone production of around 0.2 ppbv h-1 during the morning. The ozone record at DDU exhibits a maximum of 35 ppbv in July and a minimum of 18 ppbv in January. Mixing ratios at DDU are always higher than those at Neumayer (NM), another coastal Antarctic station. A noticeable difference in the ozone records at the two coastal sites lies in the larger ozone depletion events occurring from July to September at NM compared to DDU, likely due to stronger BrO episodes in relation with a larger sea ice coverage offshore that site. A second difference is the large day-to-day fluctuations which are observed from November to January at DDU but not at NM. That is attributed to a stronger impact at DDU than at NM of air masses coming from the Antarctic plateau. The consequences of such a high oxidizing property of the atmosphere over East Antarctica are discussed with regard to the dimethylsulfide (DMS) chemistry.

  9. Superfund Record of Decision (EPA Region 9): Mesa Area Ground Water Contamination, Mesa, AZ. (First remedial action), September 1991. Final report

    SciTech Connect

    Not Available

    1991-09-27

    The 80-acre Mesa Area Ground Water Contamination site is a semiconductor manufacturing facility in Mesa, Maricopa County, Arizona. Land use in the area is predominantly industrial and residential. The site overlies two aquifers: a Lower Alluvial Aquifer (LAA), which is used by the residents of Mesa as a drinking water source, and an Upper Alluvial Aquifer (UAA). Since 1966, Motorola, Inc., has used the site for the production of semiconductors and the storage of chemicals in an underground storage system. The selected remedial action for the site includes treating shallow onsite soil using soil vapor extraction, controlling VOC emissions using carbon adsorption, followed by offsite disposal of carbon residuals; onsite and offsite pumping of contaminated ground water; treating the ground water onsite using vacuum degasification, followed by carbon adsorption to remove VOCs; discharging the treated water from the degasifier to the deionized water treatment plant for reuse in manufacturing and other facility processes; and disposing of remaining wastewater at a publicly owned treatment works.

  10. 13. VIEW OF WESTERN CANAL EAST OF CARRIAGE LANE IN ...

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

    13. VIEW OF WESTERN CANAL EAST OF CARRIAGE LANE IN TEMPE, SHOWING DROP STRUCTURE AND GROUNDWATER PUMP. THIS IS THE LAST OF FOUR PUMPS WHICH FEED DIRECTLY INTO THE CANAL BETWEEN ALMA SCHOOL ROAD AND PRICE ROAD. ON THIS DAY, ALL FOUR PUMPS, OPERATING AT FULL OUTPUT, HAVE CONSIDERABLY SWELLED THE FLOW TO THE CANAL. NOTE THE OLD FASHIONED BRICKWORK ON THE NORTH BANK. - Western Canal, South side of Salt River between Tempe, Phoenix & Mesa, Mesa, Maricopa County, AZ

  11. Wet Deposition of Black Carbon at a Remote Site in the East China Sea

    NASA Astrophysics Data System (ADS)

    Mori, T.; Kondo, Y.; Moteki, N.; Ohata, S.; Matsui, H.; Oshima, N.; Iwasaki, A.

    2014-12-01

    Black carbon (BC) is produced by incomplete combustion of fossil fuels and biomass, and removed by wet deposition. Long-term measurements of BC wet deposition are very important to understand BC loss because wet deposition is major sink of BC. We measured BC mass concentrations in air (MBC) and in rainwater (CBC) simultaneously at Cape Hedo on Okinawa Island, Japan, in the East China Sea, from April 2010 to March 2013. MBC was measured by a Continuous Soot Monitoring System (COSMOS) and CBC was measured by a combination of an ultrasonic nebulizer and a Single-Particle Soot Photometer (SP2). The monthly averaged MBC, CBC, and BC wet deposition flux (FBC) showed marked seasonal variations, being highest in spring. The FBC during the four spring seasons (51 mg m-2 (3month)-1) was about 77% of the annual average of FBC (65.5 mg m-2 yr-1). This flux is comparable to the average BC net flux (emission - deposition) over North China, indicating the importance of precipitation amount over the East China Sea as a sink of BC transported from North China. In summer, CBC values were correlated with MBC (r2 = 0.47) for rain events associated with local convective activity, as identified by the convective available potential energy (CAPE). A-one dimensional thermodynamic model successfully explained the relation between MBC and CBC.

  12. Completion Report for Well ER-EC-12 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2011-04-30

    Well ER-EC-12 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada National Security Site (formerly known as the Nevada Test Site), Nye County, Nevada. The well was drilled in June and July 2010 as part of the Pahute Mesa Phase II drilling program. The primary purpose of the well was to provide detailed hydrogeologic information in the Tertiary volcanic section in the area between Pahute Mesa and the Timber Mountain caldera complex that will help address uncertainties within the Pahute Mesa–Oasis Valley hydrostratigraphic model. In particular, the well was intended to help define the structural position and hydraulic parameters for volcanic aquifers potentially down-gradient from historic underground nuclear tests on Pahute Mesa. It may also be used as a long-term monitoring well.

  13. Completion Report for Well ER-EC-15 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2011-05-31

    Well ER-EC-15 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada National Security Site (formerly known as the Nevada Test Site), Nye County, Nevada. The well was drilled in October and November 2010, as part of the Pahute Mesa Phase II drilling program. The primary purpose of the well was to provide detailed hydrogeologic information in the Tertiary volcanic section in the area between Pahute Mesa and the Timber Mountain caldera complex that will help address uncertainties within the Pahute Mesa–Oasis Valley hydrostratigraphic model. In particular, the well was intended to help define the structural position and hydraulic parameters of volcanic aquifers potentially down-gradient from underground nuclear tests on Pahute Mesa. It may also be used as a long-term monitoring well.

  14. Wet deposition of black carbon at a remote site in the East China Sea

    NASA Astrophysics Data System (ADS)

    Mori, T.; Kondo, Y.; Ohata, S.; Moteki, N.; Matsui, H.; Oshima, N.; Iwasaki, A.

    2014-09-01

    Mass concentrations of black carbon (BC) in air (MBC) and rainwater (CBC) in the East China Sea were measured at Hedo on Okinawa Island, Japan, from April 2010 to March 2013. The monthly averaged MBC and CBC showed marked seasonal variations, being highest in spring (0.32 ± 0.13 µg m-3 and 92 ± 76 µg L-1, respectively) and lowest in summer (0.06 ± 0.03 µg m-3 and 8.0 ± 4.1 µg L-1, respectively). The high MBC and CBC in spring were associated with transport of air masses from the Asian continent by northwesterly winds. The BC wet deposition flux (FBC), estimated as the product of CBC and precipitation amount, also showed a distinct seasonal variation. The monthly average FBC during the four spring seasons (16.8 ± 6.7 mg m-2 month-1) was about 3 times higher than the annual average FBC (5.5 ± 9.9 mg m-2 month-1) owing to the high CBC and precipitation amount in spring. As a result, about 76% of the annual BC deposition occurred in spring on average. The FBC in spring is comparable to the average BC net flux in North China, indicating the importance of precipitation over the East China Sea as a sink of BC transported from North China. In summer, CBC values were correlated with MBC for rain events associated with local convective activity, as identified by the convective available potential energy. A one-dimensional thermodynamic model successfully explained the relation between CBC and MBC.

  15. In-Situ Air Permeability Measurements Using the Cone Permeameter at the 200 East Area of the Hanford Site

    SciTech Connect

    TROYER, G.L.

    1999-03-31

    This report documents the field demonstration of the Cone Permeameter{trademark} (CPer) conducted at the Immobilization Low-Activity Waste (ILAW) site in the 200 East area of the Department of Energy's (DOE) Hanford facility. The demonstration was conducted using the Hanford Site Cone Penetration Platform (CPP) shown in Figure 1.1. The purpose of the technology demonstration was to (1) gather baseline data and evaluate the CPer's ability to measure air permeability in arid sands, silts and gravels; and (2) to determine the system's ability to replicate permeability profiles with multiple pushes in close proximity. The demonstration was jointly conducted by Applied Research Associates, Inc. (ARA) and Science and Engineering Associates (SEA). This report satisfies the requirements of ARA's contract No.2075 to Lockheed Martin Hanford Company. The report is organized into six major sections. This first section presents an introduction and outline to the report. Section 2 contains a discussion of the technologies used for the demonstration. Section 3 contains a brief description of the site where the demonstration was conducted. Section 4 describes the testing methodology and chronology. Section 5 presents the results obtained during the field test program. Comparisons between these results and existing site data are developed and discussed in Section 5. A conclusion and recommendation section is presented in Section 6 of the report.

  16. Foam frac in the Mesa Verde

    SciTech Connect

    Not Available

    1981-04-01

    Bittercreek Fed 1-3 is a gas well tapping the Mesaverde in the Asphalt Creek area south of Vernal, Utah, in the Uinta basin. The job was to pump 216,000 lb of 20/40 sand in 123,360 gal foam through 4 sets of perforations between 6030 ft and 6293 ft. In January 1981, Ensearch Exploration set in motion the first foam fracture done by the company in the Mesa Verde - possibly the first foam frac ever done in the Mesa Verde. Smith Energy Services performed the stimulation, delivering the highest concentration of proppant ever pumped in the Rocky Mt. - 4 ppg 20/40 sand/gal of foam at the formation. The Bittercreek Fed 1-3 had been treated conventionally on 3 previous occasions. In turning to foam fracture treatment, Ensearch hoped to minimize formation damage and maximize production in the fluid sensitive formation.

  17. The Mesa Arizona Pupil Tracking System

    NASA Technical Reports Server (NTRS)

    Wright, D. L.

    1973-01-01

    A computer-based Pupil Tracking/Teacher Monitoring System was designed for Mesa Public Schools, Mesa, Arizona. The established objectives of the system were to: (1) facilitate the economical collection and storage of student performance data necessary to objectively evaluate the relative effectiveness of teachers, instructional methods, materials, and applied concepts; and (2) identify, on a daily basis, those students requiring special attention in specific subject areas. The system encompasses computer hardware/software and integrated curricula progression/administration devices. It provides daily evaluation and monitoring of performance as students progress at class or individualized rates. In the process, it notifies the student and collects information necessary to validate or invalidate subject presentation devices, methods, materials, and measurement devices in terms of direct benefit to the students. The system utilizes a small-scale computer (e.g., IBM 1130) to assure low-cost replicability, and may be used for many subjects of instruction.

  18. Addendum to the East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan Oak Ridge, Tennessee

    SciTech Connect

    SAIC

    2011-04-01

    The East Tennessee Technology Park Site-Wide Residual Contamination Remedial Investigation Work Plan (DOE 2004) describes the planned fieldwork to support the remedial investigation (RI) for residual contamination at the East Tennessee Technology Park (ETTP) not addressed in previous Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) decisions. This Addendum describes activities that will be conducted to gather additional information in Zone 1 of the ETTP for groundwater, surface water, and sediments. This Addendum has been developed from agreements reached in meetings held on June 23, 2010, August 25, 2010, October 13, 2010, November 13, 2010, December 1, 2010, and January 13, 2011, with representatives of the U. S. Department of Energy (DOE), U. S. Environmental Protection Agency (EPA), and Tennessee Department of Environment and Conservation (TDEC). Based on historical to recent groundwater data for ETTP and the previously completed Sitewide Remedial Investigation for the ETTP (DOE 2007a), the following six areas of concern have been identified that exhibit groundwater contamination downgradient of these areas above state of Tennessee and EPA drinking water maximum contaminant levels (MCLs): (1) K-720 Fly Ash Pile, (2) K-770 Scrap Yard, (3) Duct Island, (4) K-1085 Firehouse Burn/J.A. Jones Maintenance Area, (5) Contractor's Spoil Area (CSA), and (6) Former K-1070-A Burial Ground. The paper presents a brief summary of the history of the areas, the general conceptual models for the observed groundwater contamination, and the data gaps identified.

  19. Characteristics and potential sources of atmospheric mercury at a subtropical near-coastal site in East China

    NASA Astrophysics Data System (ADS)

    Yu, Ben; Wang, Xun; Lin, Che-Jen; Fu, Xuewu; Zhang, Hui; Shang, Lihai; Feng, Xinbin

    2015-08-01

    To evaluate the impact of regional mercury (Hg) emissions and understand possible source regions of atmospheric Hg in Eastern China, 2 year observation for speciated atmospheric Hg was conducted at the Dameishan Atmospheric Observatory, a mountain site near the east coast of China. The observed concentration of total gaseous Hg (TGM) was 3.3 ± 1.4 ng m-3. During the sampling period, gaseous oxidized Hg and particulate bound Hg were 6.7 ± 4.3 pg m-3 and 180 ± 110 pg m-3 in winter and 5.9 ± 3.4 pg m-3 and 130 ± 100 pg m-3 in spring, respectively. The relatively high mean concentration of TGM was mainly caused by regional anthropogenic emissions and occasional long-range transport from domestic source regions. Seasonal variation in the TGM concentration was observed with lower values in the wet monsoon season (from May to September) and higher values in the dry monsoon season (from October to April). Backward trajectories and potential source contribution function analysis suggested that anthropogenic Hg emission from coal combustion in the Yangtze River Delta region was the most likely cause for the elevated TGM concentrations. Relatively clean air originating from the East China Sea was the most possible cause for the observed low TGM concentrations. Positive correlation between TGM concentration and air quality index suggests that emissions that influenced regional air quality contributed to the elevated TGM concentrations.

  20. The MESA accelerometer for space application

    NASA Technical Reports Server (NTRS)

    Lange, William G.; Dietrich, Robert W.

    1990-01-01

    An electrostatically suspended proof mass in the Miniature Electrostatic Accelerometer (MESA) is used to measure acceleration in the submicro-g range. Since no fixed mechanical suspension (such as springs or strings) is used, the constrainment scaling can be changed electrically after being placed in orbit. A single proof mass can sense accelerations in three axes simultaneously. It can survive high-g pyrotechnic-generated shocks and launch environments while unpowered.

  1. Discovery of Off-Axis Melt Lenses at the RIDGE-2000 East Pacific Rise Integrated Studies Site

    NASA Astrophysics Data System (ADS)

    Canales, J.; Carbotte, S. M.; Mutter, J. C.; Nedimović, M. R.; Carton, H.; Xu, M.; Newman, K.; Aghaei, O.; Marjanović, M.; Stowe, L.

    2008-12-01

    The first multi-streamer 3D seismic reflection experiment conducted aboard the R/V Marcus Langseth was carried out in July-August 2008 at the RIDGE-2000 Integrated Studies Site at the East Pacific Rise between 9°37'N and 9°57'N. One of the major findings of this cruise is the presence of at least three regions with prominent near-axis crustal reflectors that we interpret as off-axis melt lenses (OAML) injected at mid-crustal levels to both the east and west of the ridge crest. In some instances these regions are associated with subtle topographic expressions of seafloor volcanism. The first set of OAML reflections was discovered near 9° 54'N at distances from the ridge axis that range from ~4 to ~7 km, and extending ~6.3 km in the ridge-parallel direction. Two-way travel times from the seafloor to the OAML are 750-830 ms, which correspond to depths of ~1,800-2,000 m (assuming an average upper crustal velocity of 4.7 km/s), although in some cases there is evidence for deeper (~1,420 ms, or ~3,330 m) reflections farther off-axis forming a staircase-like system of melt lenses. A second set of OAML reflections was discovered further south near 9° 39'N also within 3-6 km east of the spreading axis, and extending ~3.3 km in the ridge-parallel direction. Crustal travel times to these OAML reflections are 710-830 ms (1,700-2,000 m below seafloor). In this region the OAML is locally underlain by deeper reflections at depths of 1,300 ms (~3,100 m) that could indicate off-axis melt sill intrusions at multiple levels. A smaller OAML was found within 2 km west of the axis near 9° 52'N. In this paper we present preliminary cross-sections of this dataset to evaluate the extent and general characteristics of these off-axis events, which highlight the importance of off-axis magmatism in crustal accretion along this section of the East Pacific Rise.

  2. High Temperature Superconducting Terahertz Emitters with Various Mesa Structures

    NASA Astrophysics Data System (ADS)

    Delfanazari, Kaveh; Tsujimoto, M.; Kashiwagi, T.; Asai, H.; Kitamura, T.; Yamamoto, T.; Sawamura, M.; Ishida, K.; Watanabe, C.; Sekimoto, S.; Minami, H.; Tachiki, M.; Hattori, T.; Klemm, R. A.; Kadowaki, K.

    2013-03-01

    In 2007, the first observation of the coherent terahertz (THz) electromagnetic (EM) waves from a mesa structures of intrinsic Josephson junctions (IJJs) in high temperature superconductor Bi2Sr2CaCu2O8+? (Bi-2212) is reported. The ac-Josephson effect as well as the cavity resonance conditions is considered as the principle mechanism of the THz radiation. In order to understand the cavity effect in THz radiation from IJJ mesas more clearly, we studied mesas with various geometries; various kinds of triangles, and pentagonal mesas with various sizes and thicknesses. The focused ion beam (FIB) milling technique is used in all mesa fabrications. In this talk, we discuss our recent progress in THz emission observation in pentagonal mesas. This work has been supported in part by CREST-JST (Japan Science and Technology Agency), WPI-MANA project (NIMS).

  3. A craniometrical analysis of the Early Bronze Age dogs from Vucedol site (East Slavonia, Croatia).

    PubMed

    Mihelić, Damir; Pavić, Mirela; Hincak, Zdravka

    2013-03-01

    During archaeological campaigne on Vucedol site 7 crania and cranial fragments together with 10 halfs of lower jaws were found. Due to existance of crania and lower jaws damages and therefore lack of preserved craniometrical points, it was not possible to measure the same craniometrical lengths on all the samples. Apart from craniometrical measurements, 6 craniometrical indices and ratios were calculated. Comparison of calculated values and values of craniometrical indices and ratios identify dog's crania from Vucedol site as dolichocephalic cranial type. Mutual comparison of all analyzed craniometrical values for crania and lower jaws of dog's crania don't show a significant difference in size and ratios of individual measures, nor significant deviation in value of the samples of other Vucedol culture sites. This point out on type of dogs with similar appearance which tallness and form respond to smaller dog's breed, in the first place a type of Croatian sheepdog or Hungarian Mudi. PMID:23697279

  4. Changes in nematode communities in different physiographic sites of the condor seamount (north-East atlantic ocean) and adjacent sediments.

    PubMed

    Zeppilli, Daniela; Bongiorni, Lucia; Serrão Santos, Ricardo; Vanreusel, Ann

    2014-01-01

    Several seamounts are known as 'oases' of high abundances and biomass and hotspots of biodiversity in contrast to the surrounding deep-sea environments. Recent studies have indicated that each single seamount can exhibit a high intricate habitat turnover. Information on alpha and beta diversity of single seamount is needed in order to fully understand seamounts contribution to regional and global biodiversity. However, while most of the seamount research has been focused on summits, studies considering the whole seamount structure are still rather poor. In the present study we analysed abundance, biomass and diversity of nematodes collected in distinct physiographic sites and surrounding sediments of the Condor Seamount (Azores, North-East Atlantic Ocean). Our study revealed higher nematode biomass in the seamount bases and values 10 times higher in the Condor sediments than in the far-field site. Although biodiversity indices did not showed significant differences comparing seamount sites and far-field sites, significant differences were observed in term of nematode composition. The Condor summit harboured a completely different nematode community when compared to the other seamount sites, with a high number of exclusive species and important differences in term of nematode trophic diversity. The oceanographic conditions observed around the Condor Seamount and the associated sediment mixing, together with the high quality of food resources available in seamount base could explain the observed patterns. Our results support the hypothesis that seamounts maintain high biodiversity through heightened beta diversity and showed that not only summits but also seamount bases can support rich benthic community in terms of standing stocks and diversity. Furthermore functional diversity of nematodes strongly depends on environmental conditions link to the local setting and seamount structure. This finding should be considered in future studies on seamounts, especially in view of the potential impacts due to current and future anthropogenic threats. PMID:25541988

  5. The Apame Project: Archeo-Paleoseismology for the Protection of Archeological Sites and Cultural Heritage in the Middle East

    NASA Astrophysics Data System (ADS)

    APAME Working Group

    2007-12-01

    The APAME EC project (Contract ICA3-CT-2002-10024) consists of multidisciplinary studies of seismically active regions along the Dead Sea Fault. Several medieval cities, citadels, fortresses and known archeological sites of the Middle East suffered of severe earthquake damage in the past. A repetition of similar seismic events nowadays will cause tremendous damage and destruction mainly due to the last century increase in population and modern constructions. In the APAME project, we combine historical, archeo-paleoseismological and earthquake hazard studies and provide an integrated analysis of their consequent seismic hazard. The results are: 1) An inventory with maps of archeological and cultural sites affected by past earthquakes and detailed archeoseismological and paleoseismological studies of some specific sites using precise dating techniques. 2) An analysis of damage distribution based on the historical archives, new documents and field investigations and preparation of updated sesimicity catalogue of past earthquakes. 3) Investigations of man-made constructions and building practices for each site with a comparison between heavily damaged and undamaged buildings. Striking results are ~ 40 m fault offset of a Tell site in the Amik Basin (Turkey), the severe earthquake damage in the remaining "lost villages" and ~ 13.6 m offset of a Roman Aqueduct in northern Syria, the trace of the 1837 and 1759 earthquake fault ruptures in southern Lebanon, and the constraint of fault slip rate using offset streams and paleoclimatic reconstructions along the Jordan Valley Fault. A fault segmentation is obtained from the compiled instrumental and historical earthquake catalogue and related damage distribution. The rich historical seismicity catalogue and fault segmentation combined with the tectonic and geodetic strain pattern along the DSF contribute to the characterization of rupture zones with a potential for a future large earthquake.

  6. Changes in Nematode Communities in Different Physiographic Sites of the Condor Seamount (North-East Atlantic Ocean) and Adjacent Sediments

    PubMed Central

    Zeppilli, Daniela; Bongiorni, Lucia; Serrão Santos, Ricardo; Vanreusel, Ann

    2014-01-01

    Several seamounts are known as ‘oases’ of high abundances and biomass and hotspots of biodiversity in contrast to the surrounding deep-sea environments. Recent studies have indicated that each single seamount can exhibit a high intricate habitat turnover. Information on alpha and beta diversity of single seamount is needed in order to fully understand seamounts contribution to regional and global biodiversity. However, while most of the seamount research has been focused on summits, studies considering the whole seamount structure are still rather poor. In the present study we analysed abundance, biomass and diversity of nematodes collected in distinct physiographic sites and surrounding sediments of the Condor Seamount (Azores, North-East Atlantic Ocean). Our study revealed higher nematode biomass in the seamount bases and values 10 times higher in the Condor sediments than in the far-field site. Although biodiversity indices did not showed significant differences comparing seamount sites and far-field sites, significant differences were observed in term of nematode composition. The Condor summit harboured a completely different nematode community when compared to the other seamount sites, with a high number of exclusive species and important differences in term of nematode trophic diversity. The oceanographic conditions observed around the Condor Seamount and the associated sediment mixing, together with the high quality of food resources available in seamount base could explain the observed patterns. Our results support the hypothesis that seamounts maintain high biodiversity through heightened beta diversity and showed that not only summits but also seamount bases can support rich benthic community in terms of standing stocks and diversity. Furthermore functional diversity of nematodes strongly depends on environmental conditions link to the local setting and seamount structure. This finding should be considered in future studies on seamounts, especially in view of the potential impacts due to current and future anthropogenic threats. PMID:25541988

  7. Carbon sequestration potential in reclaimed mine sites in seven east-central states.

    PubMed

    Sperow, Mark

    2006-01-01

    Terrestrial systems represent a significant potential carbon (C) sink to help mitigate or offset greenhouse gas emissions. Nearly 3.2 Mha are permitted for mining activities in the United States, which are required to be reclaimed with vegetative cover. While site-specific studies have assessed C accumulation on reclaimed mine sites, regional analyses to estimate potential C increases have not been conducted. For this analysis, potential C sequestration is analyzed on 567,000 ha of mine land in a seven-state region reclaimed to cropland, pasture, or forest. Carbon accumulation is estimated for cropland, pasture, and forest soils, forest litter layer, and aboveground biomass by estimating average annual rates of C accumulation from site-specific and general C sequestration studies. The average annual rate of C storage is highest when mine land is reclaimed to forest, where the potential sequestration is 0.7 to 2.2 Tg yr(-1). The C from soils, litter layer, and biomass from mine lands reclaimed to forest represents 0.3 to 1.0% of the 1990 CO2 emissions from the study region (919 Tg CO2). To achieve the greenhouse gas (GHG) emission reduction goal of 7% below the 1990 level as proposed by the Kyoto Treaty requires CO2 emissions in the study area to be reduced by just over 64 Tg CO2. The potential carbon storage in mine sites reclaimed to forest could account for 4 to 12.5% of these required reductions. PMID:16825463

  8. Black carbon and total carbon measurements at urban and rural sites in Kenya, East Africa

    NASA Astrophysics Data System (ADS)

    Gatari, Michael J.; Boman, Johan

    This paper reports measurements of black carbon (BC) and total carbon (TC) (TC=BC+organic carbon) in the lower troposphere in Nairobi and the towns of Nanyuki and Meru in Kenya. The rural sites of Nanyuki and Meru are both located on the equator on the northwestern and northeastern slopes of Mount Kenya, respectively. Particles were collected for 24 h on glass fibre filters using a dichotomous impactor. The content of TC and BC was analysed using a carbon-hydrogen-nitrogen analyser and a black smoke reflectometer. The mean TC concentration in Nanyuki was found to be two times higher than that of Meru, 14±2 and 7±1 μg m -3, respectively. The measured BC concentration in Meru (1.4±0.1 μg m -3) was twice that of Nanyuki (0.72±0.06 μg m -3). The organic carbon (OC) concentration was estimated from the difference between the measured TC and BC. The obtained mean concentrations were lower than those found in the literature for Asia and USA but higher than those of some European cities. The local burning of biomass was seen as the main source of carbonaceous aerosols at all measurement sites. The Nanyuki site exhibited OC concentrations comparable to those of the urban site in Nairobi. Nairobi had the highest concentration of both TC and BC. Vehicular and waste burning emissions in Nairobi may have enriched the carbonaceous aerosols.

  9. Seasonal variations of black carbon in rainwater at a remote site in the East China Sea

    NASA Astrophysics Data System (ADS)

    Mori, T.; Kondo, Y.; Moteki, N.; Ohata, S.; Iwasaki, A.

    2013-12-01

    Black carbon (BC) particles are emitted into the atmosphere by incomplete combustion of fossil fuels and biomass, and removed by wet deposition. Because wet deposition is the major sink of BC, systematic measurements of wet deposition of BC are critical for quantitative understanding loss of BC. We measured BC mass concentration in the air (Mair) and in rainwater (Mrain) simultaneously at Cape Hedo on Okinawa Island, Japan, in the East China Sea, from April 2010 to March 2013. An automated wet-only sampler was used to collect rainwater during a 24 period. Mair was measured by a Continuous Soot Monitoring System (COSMOS) and Mrain was measured by a system consisting of an ultrasonic nebulizer and a Single Soot Photometer (SP2). The monthly averaged Mair and Mrain showed marked seasonal variations: Mair and Mrain were highest in spring (0.32×0.13 μg m-3 and 92×76 μg L-1, respectively), and lowest in summer (0.06×0.03 μg m-3 and 8.0×4.1μg L-1, respectively). The BC deposition flux FBC, defined as the product of Mrain and amount of precipitation, also showed a distinct seasonal variation. The average FBC in spring was about 77% of the annual average FBC, which was 65.5 mg m-2 year-1. The highest FBC in spring was due to the high Mrain and precipitation amount. In turn, the high Mrain was caused by the Mair values in spring associated with frequent transport of high BC air masses from China by north-westerly wind in this season. The BC scavenging ratio, defined as the Mrain/Mair ratio, was highly variable throughout the year: the ratio in spring was about 6 times higher than in fall.

  10. Ground motion produced at Yucca Mountain from Pahute Mesa underground nuclear explosions

    SciTech Connect

    Vortman, L.J.

    1986-02-01

    Prediction equations were developed for peak vector acceleration, velocity, and displacement from underground nuclear explosions at Pahute Mesa. Separate equations were developed using data from stations on rock and alluvium, rock only, and alluvium only. Equations were further subdivided into three groups: all data, deletion of data with known site anomalies, and additional deletion of Yucca Mountain data. Differences in the prediction equations for the three groups using rock and alluvium and rock only were small. Alluvium only data were too sparse for valid equations. Data were normalized to remove the effects of source-energy coupling, and prediction equations recalculated. Anomalously high accelerations had been observed previously at Engine Test Stand 1 in the Nuclear Rocket Development Station area. These new data show vector accelerations 4 to 10 times predictions from events in Area 20 and smaller enhancements from events in Area 19. The area receiving the greater accelerations is concentrated at Engine Test Stand 1 and diminishes within about 4 km east and west of that station. Examination of velocity from event location to the point of measurement suggests transmission paths with a high velocity layer at a shallower depth on the path from Area 19 than from Area 20. Measurements made at Yucca Mountain indicate that qualitatively similar large accelerations exist at Yucca Mountain but with the largest observed to date only 4.19 times prediction. Since the data set for Yucca Mountain is relatively small, the possibility exists for even greater enhancements for underground nuclear explosions in locations other than those included in the data set.

  11. Relocation of the 1936 Mojokerto skull discovery site near Perning, East Java.

    PubMed

    Huffman, O F; Zaim, Y; Kappelman, J; Ruez, D R; de Vos, J; Rizal, Y; Aziz, F; Hertler, C

    2006-04-01

    The fossil calvaria known as the Mojokerto child's skull was discovered in 1936, but uncertainties have persisted about its paleoenvironmental context and geological age because of difficulties in relocating the discovery site. Past relocation efforts were hindered by inaccuracies in old base maps, intensive post-1930s agricultural terracing, and new tree and brush growth. Fortunately geologic cross sections and site photographs from 1936-1938-not fully utilized in past relocation fieldwork-closely circumscribe site geography and geology. These documents match the conditions at just one sandstone outcrop. It is situated on the southern margin of a topographic nose at the upper end of a approximately 18 m-wide gully ( approximately 0663760 m E, 9183430 m N, UTM Zone 49 M), approximately 15 m southeast of the Kumai et al. (1985) relocation. The relocated discovery bed is approximately 3.3 m of fossiliferous pebbly sandstone, a river-channel deposit cut into tuffaceous mudstone. The sandstone and mudstone beds correspond to original site descriptions. Pebbly sandstone is also found within the skull. The calvaria is well-preserved and taphonomically similar to large and fragile specimens found among several hundred vertebrate fossils excavated from the sandstone in 2001-2002. Since no well-preserved fossils were found intact at the surface of the sandstone, the good condition of the Mojokerto skull suggests that it was buried fully when discovered. The relocated hominin bed is the uppermost fluvial sandstone of a marine-deltaic sequence in the upper Pucangan Formation. The Mojokerto child probably died along the ancient seacoast, judging from the large extent of the deltaic facies and evidence that the calvaria experienced minimal transport. The relocated discovery bed is approximately 20 m stratigraphically above the horizon from which the widely cited 1.81+/-0.04 Ma (40)Ar/(39)Ar date for the skull was obtained. Additional field and laboratory results will be required to determine the skull's age. PMID:16386780

  12. Deriving a speciated atmospheric nitrogen budget at Auchencorth Moss, a background site in South East Scotland

    NASA Astrophysics Data System (ADS)

    Twigg, Marsailidh; Aruffo, Eleonora; Kentisbeer, John; Malley, Christopher; Leeson, Sarah; Jones, Matthew; Nemitz, Eiko; Di Carlo, Piero; Braban, Christine

    2015-04-01

    Since 2006, the EMEP supersite, Auchencorth Moss, has routinely measured HNO3, HONO, NO, NO2, NH3 and speciated aerosols including NH4+ and NO3- in PM2.5 and PM10. It is known that other reactive N species are important in the atmosphere at background sites including PANs, peroxy nitrates, alkyl nitrates, ClNO2 and N2O5 and routine measurements are not frequently assessed against these other species. The following study presents the highlights from an intensive study, in spring 2014, where non-routine measurements (TD-LIF and PAN GC) were carried out alongside routine measurements (MARGA, ANNOx, NOxThermoFisher Analyser). The objectives of the study were to understand further the role of non-routine measured species in the N budget at this site and to try to identify potential artefacts in current routine measurements. Initial comparison studies suggest that routine measurements capture well the temporal variations in NOx and HNO3, though questions remain on the accuracy of the measurements. During the study on average low concentrations of all species (NO2 = 1.58 ppb, NH3 = 2.3 ppb, HNO3 = 0.09 ppb, HONO= 0.07 ppb) were observed, though there were periods where polluted air masses arrived at the site resulting in an increase in both routine and non-routine measured species. As well as air masses transporting N species, there was evidence of atmospheric chemical transformations of N species at the site, including the photochemical production of PAN.

  13. Perchlorate in fish from a contaminated site in east-central Texas.

    PubMed

    Theodorakis, Christopher; Rinchard, Jacques; Anderson, Todd; Liu, Fujun; Park, June-Woo; Costa, Filipe; McDaniel, Leslie; Kendall, Ronald; Waters, Aaron

    2006-01-01

    Perchlorate, a known thyroid endocrine disruptor, contaminates surface waters near military instillations where solid fuel rocket motors are manufactured or assembled. To assess potential perchlorate exposure to fish and the human population which may feed on them, fish were collected around the Naval Weapons Industrial Reserve Plant in McLennan County, TX, and analyzed for the presence of the perchlorate anion. The sampling sites included Lake Waco and Belton Lake, and several streams and rivers within their watersheds. The general tendency was that perchlorate was only found in a few species sampled, and perchlorate was not detected in every individual within these species. When detected in the fish, perchlorate tissue concentrations were greater than that in the water. This may be due to highly variable perchlorate concentrations in the water coupled with individual-level variation in elimination from the body, or to routes of exposure other than water. PMID:15993996

  14. 36 CFR 7.39 - Mesa Verde National Park.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Mesa Verde National Park. 7.39 Section 7.39 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.39 Mesa Verde National Park. (a) Visiting...

  15. Mathematics, Engineering Science Achievement (MESA). Washington's Community and Technical Colleges

    ERIC Educational Resources Information Center

    Washington State Board for Community and Technical Colleges, 2014

    2014-01-01

    Growing Science, Technology, Education, and Mathematics (STEM) talent Washington MESA--Mathematics Engineering Science Achievement--helps under-represented community college students excel in school and ultimately earn STEM bachelor's degrees. MESA has two key programs: one for K-12 students, and the other for community and technical college…

  16. 36 CFR 7.39 - Mesa Verde National Park.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Mesa Verde National Park. 7.39 Section 7.39 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.39 Mesa Verde National Park. (a) Visiting...

  17. 36 CFR 7.39 - Mesa Verde National Park.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Mesa Verde National Park. 7.39 Section 7.39 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.39 Mesa Verde National Park. (a) Visiting...

  18. 36 CFR 7.39 - Mesa Verde National Park.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Mesa Verde National Park. 7.39 Section 7.39 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.39 Mesa Verde National Park. (a) Visiting...

  19. Correlation between meteorological conditions and aerosol characteristics at an East-Mediterranean coastal site

    NASA Astrophysics Data System (ADS)

    El-Metwally, Mossad; Alfaro, Stephane C.

    2013-10-01

    Since May 2011 Microtops sun-photometer measurements aiming to determine the aerosol optical depth (AOD) and its spectral dependence (Ångström exponent, α440/675) are performed routinely at the experimental station of the Port Said (Egypt) University (Lat.: 31.267°, Lon.: 32.26°, alt.: 21 masl). In parallel, an automated weather station is used to monitor the surface meteorological parameters (wind speed and direction, relative humidity, temperature, pressure…). This work uses the first year of original data (971 point measurements) with the double objective of determining the 1) seasonal variability of the aerosol at a site of the Egyptian Mediterranean coast, and 2) the potential correlation linking the aerosol characteristics to the surface meteorological conditions. The 3-modal nature of the statistical distribution of the Ångström exponents measured during the year shows that 3 main types of aerosols can be distinguished. The most frequent observations (54% of all cases) correspond to fine particles associated with the largest (1.41 ± 0.23) α440/675 values. The probability of observing this fine aerosol increases in low wind conditions and when the air masses come either from the south-west, which is to say from the densely populated Nile delta, or from the north, which is to say from the more distant European pollution sources. This strongly suggests an anthropogenic origin for these fine particles. At the opposite side of the size-spectrum, coarse particles associated with the lowest mode of α440/675 (0.48 ± 0.22) predominate in 33% of the observations. The probability of observing them increasing in spring when the dry and strong (> 6 m/s) desert-winds become more frequent suggests that these coarse particles are desert dust released by the wind erosion of arid surfaces. These particles are also responsible for the largest individual and monthly averaged (AOD500 = 0.50, in April) optical depths measured at the experimental site. Finally, by adding a supermicron marine component to the fine pollution aerosols advected from European sources, medium to strong winds from the north sector tend to increase the aerosol depth and decrease its spectral dependence. Besides the direct mixing of the coarse dust and fine pollution component, this effect is responsible for the occurrence of at least a part of the intermediate Ångström exponent (α440/675 = 0.91 ± 0.04) cases.

  20. Argonne National Laboratory-East summary site environmental report for calendar year 2001.

    SciTech Connect

    Golchert, N. W.; Kolzow, R. G.

    2003-02-20

    This report is a summary of the actions taken by Argonne National Laboratory in 2001 to keep the public and environment safe. Over the last year, Argonne has monitored, evaluated, and taken steps to control problems or potential problems on its DuPage County site. The problems that have or might occur are things like spilled or leaked radiological waste, non-radiological wastes or hazardous materials. Argonne is keeping its promise to be a good neighbor, and this report confirms its commitment to its neighbors, both human and environmental. Argonne's commitment to have minimal effect on the environment was tested vigorously over 2001. Argonne's first priority is keeping the people around it safe. This was verified through tests done on the air. The air can be the most damaging way to pollute an area. This is why Argonne was so extensive in its testing. They followed guidelines of the Clean Air Act, which covers radioactive emissions, asbestos, and conventional air pollutants. Air was tested, and after all calculations were finished, the effect on the public was found to be so minimal that it almost didn't register. The sources of pollutants from Argonne are exhausts from laboratories and other facilities, the steam plant that provides space heating for Argonne's buildings, and emissions from emergency generators when they are operating. The traces that were found were evaluated and reduced, even though they were originally well within regulatory limits. The same trends--further reduction of concentrations that were already safe--were found in the water analysis, as well. Water was sampled and evaluated many times over the course of the year, and what was found was good news. The radiological elements were very minimal, and most of the trace amounts were due to naturally occurring radiological sources. The only measurements that exceeded standards a few times were of total dissolved solids (TDS), essentially road salts dissolved in rainwater runoff. These problems were detected and then controlled. To put numbers to the situation, 1,600 measurements were taken over the last year, and out those measurements, only seven were outside the limits set by the Illinois Environmental Protection Agency. Argonne has another priority as well: keeping the environment around its site safe. The ecosystem surrounding Argonne, including Waterfall Glen Forest Preserve, is a valuable resource for our area. Argonne knows the value of this ecosystem and works in every way possible to keep it free of pollutants, both radiological and non-radiological. Many of the factors involved in keeping the public healthy also keep our forest and its inhabitants healthy. Argonne is not always told to keep environmental contaminants at a specific level, but the laboratory works at it anyway and often sets its own standards stricter than national and state standards. Argonne has a commitment, and that commitment leads the laboratory to be a better neighbor. Argonne is a valuable resource for the community, working to keep the public and the ecosystem safe and healthy.

  1. Argonne National Laboratory-East summary site environmental report for calendar year 2002.

    SciTech Connect

    Golchert, N. W.; Kolzow, R. G.

    2004-03-08

    Argonne performs research and development in many areas of science and technology. General fields of research at Argonne include, but are not limited to, biosciences, biotechnology, chemical engineering, chemistry, decision and information sciences, energy systems and technology, high energy physics, materials science, math and computer science, nuclear reactors, physics, and environmental science. Argonne is not, and never has been, a weapons laboratory. Several missions provide focus for Argonne scientists. Basic research helps better understand the world, and applied research helps protect and improve it. For example, the prairies of Argonne provide sites for environmental studies that provide valuable information about invader species and the food webs within ecosystems. Argonne also operates world-class research facilities, such as the Advanced Photon Source (APS), which is a national research facility funded by the U.S. Department of Energy (DOE). Scientists use high brilliance X-rays from the APS for basic and applied research in many fields. Argonne also seeks to ensure our energy future. Currently, scientists and engineers are developing cleaner and more efficient energy sources, such as fuel cells and advanced electric power generation. Argonne has spent much of its history on developing nuclear reactor technology. That research is now being applied to American and Soviet nuclear reactors to improve the safety and life of the reactors. Other Argonne research seeks to improve the way we manage our environment. For example, Argonne scientists created a new catalyst that could help carmakers eliminate 95 percent of nitrogen-oxide emitted by diesel engines by the year 2007. Research and development solutions such as these will help protect our ecosystems.

  2. Origin of elevated water levels encountered in Pahute Mesa emplacement boreholes: Preliminary investigations

    SciTech Connect

    Brikowski, T.; Chapman, J.; Lyles, B.; Hokett, S.

    1993-11-01

    The presence of standing water well above the predicted water table in emplacement boreholes on Pahute Mesa has been a recurring phenomenon at the Nevada Test Site (NTS). If these levels represent naturally perched aquifers, they may indicate a radionuclide migration hazard. In any case, they can pose engineering problems in the performance of underground nuclear tests. The origin of these elevated waters is uncertain. Large volumes of water are introduced during emplacement drilling, providing ample source for artificially perched water, yet elevated water levels can remain constant for years, suggesting a natural origin instead. In an effort to address the issue of unexpected standing water in emplacement boreholes, three different sites were investigated in Area 19 on Pahute Mesa by Desert Research Institute (DRI) staff from 1990-93. These sites were U-19az, U-19ba, and U-19bh. As of this writing, U-19bh remains available for access; however, nuclear tests were conducted at the former two locations subsequent to this investigations. The experiments are discussed in chronological order. Taken together, the experiments indicate that standing water in Pahute Mesa emplacement holes originates from the drainage of small-volume naturally perched zones. In the final study, the fluids used during drilling of the bottom 100 m of emplacement borehole U-19bh were labeled with a chemical tracer. After hole completion, water level rose in the borehole, while tracer concentration decreased. In fact, total mass of tracer in the borehole remained constant, while water levels rose. After water levels stabilized in this hole, no change in tracer mass was observed over two years, indicating that no movement of water out of the borehole is taking place (as at U- 19ba). Continued labeling tests of standing water are recommended to confirm the conclusions made here, and to establish their validity throughout Pahute Mesa.

  3. Geology, hydrology, and water quality in the vicinity of a brownfield redevelopment site in East Moline, Illinois

    USGS Publications Warehouse

    Kay, Robert T.

    2001-01-01

    An investigation of the geology, hydrology, and water quality in the vicinity of a Brownfield redevelopment site in East Moline, Illinois, was designed to determine if metals and organic compounds detected in the fill deposits in this area posed a threat to the water resources. The hydrologic features of concern at the site are surface water at a pond and surrounding wetland, the Mississippi River, and an unnamed stream and ground water in the shallow aquifer. The shallow aquifer is composed of saturated fill, sand and gravel, and weathered bedrock. The overall direction of surface- and ground-water flow in the study area is toward the Mississippi River. In the eastern part of the pond and wetland, ground water discharges to surface water. In the western part of the pond and wetland, surface water recharges to ground water. Everyday during the period for which water-level data were available, between 4.7 ' 10-4 and 1.4 ' 10-1 cubic feet of water flowed across a 1 square foot area of aquifer. Variations in values for oxidation-reduction potential and specific conductance may be affected by heterogeneity in the chemical composition of the fill and unconsolidated deposits and the bedrock units. Chemical and biological processes are altering the chemistry of the water in the pond relative to its ground-water source. Concentrations of iron and manganese in water samples appear to be affected by the local geochemical environment in the aquifer. The data do not indicate that contaminants in the fill material are having a substantial adverse affect on surface- or ground-water quality in the study area.

  4. Chemical composition and mass size distribution of PM1.0 at an elevated site in central east China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Hu, G. Y.; Shen, X. J.; Wang, Y. Q.; Wang, T. T.; Wang, D. Z.; Zhao, Y.

    2014-06-01

    Size-resolved aerosol chemical compositions were measured continuously for one and half years with an aerosol mass spectrometer (AMS) to characterize the mass and size distributions (MSDs) of each component in bulk, fresh and aged submicron particles (approximately PM1.0) at Mountain Tai, an elevated site in Central East China (CEC) from June 2010 to January 2012. The majority of the regionally-dispersed aerosols were found to be contributed from short distance mixed aerosol, mostly from its south with organics and sulfate as the major components. The annual mean mass concentrations of organics, sulfate, nitrate, ammonium and chloride were 11.2, 9.2, 7.2, 5.8 and 0.95 μg m-3, respectively, which are much lower for organics and sulfate, and slightly lower for nitrate, ammonium and chloride than those at the nearby surface rural sites. High organics were observed for all four seasons, and the relatively fresh organic aerosol (OA) containing high proportion of less-photo chemically OA, were found from long-range transported aerosol from northwest. Semi-volatile and low-volatile oxidized OAs together contributed approximately 49%, 55% in spring and 72% and 51% in winter of total OA, showing at least 50% of OA can be attributable to SOA. Seasonally, the chemical components at the elevated site showed a "winter high and autumn low" pattern, with organics, sulfate and ammonium peaking in summer. Though no obvious differences of MSDs were seen for various chemical components in the planetary boundary layer (PBL) and free troposphere (FT), the concentrations were a factor of 5-7 higher in PBL than in FT. The averaged MSDs of particles between 30-1000 nm for organics, sulfate, nitrate, and ammonium are approximately log-normal with similar mass median diameters (MMDs) of 539, 585, 542, and 545 nm, respectively, which were slightly larger than those in ground sites within North China Plain (NCP). Obvious differences in MMDs were found between fresh and aged aerosols for sulfate and ammonium, with smaller increased size-factors for the Mt. Tai aerosols than those in less polluted areas. All these exhibit the relative aged and well-mixed aerosol observed.

  5. Geohydrologic data and models of Rainier Mesa and their implications to Yucca Mountain

    SciTech Connect

    Wang, J.S.Y.; Cook, N.G.W.; Wollenberg, H.A.; Carnahan, C.L.; Javandel, I.; Tsang, C.F.

    1993-01-01

    The geohydrologic data collected at Rainier Mesa provide the only extensive observations in tunnels presently available on flow and transport in tuff units similar to those of a potential nuclear waste repository at Yucca Mountain. This information can, therefore, be of great value in planning the Exploratory Studies Facility (ESF) testing in underground drifts at Yucca Mountain. In this paper, we compare the geohydrologic characteristics of tuff units of these two sites and summarize the hydrochemical data indicating the presence of nearly meteoric water in Rainier Mesa tunnels. A simple analytic model is used to evaluate the possibility of propagating transient pulses of water along fractures or faults through the Paintbrush nonwelded tuff unit to reach the tunnel beds below. The results suggest that fast flow could occur without significant mixing between meteoric fracture water and matrix pore water. The implications of these findings on planning for the ESF Calico Hills study at Yucca Mountain are discussed.

  6. Characterization of Mesa Verde black-on-white ceramics from southwest Colorado

    SciTech Connect

    Glowacki, D.M.; Glascock, M.D.

    1994-12-31

    The chemical characterization of ceramics using neutron activation analysis (NAA) is rapidly becoming an important means of obtaining information about the nature of ceramic production and exchange in the Southwest. However, until now, NAA has never been applied to Pueblo III (A.D. 1150-1300) ceramics from the Mesa Verde region. This study involves the characterization of Mesa Verde black-on-white bowls from the Castle Rock and Sand Canyon Pueblo sites in southwestern Colorado. As the distinctions in the different clay sources are potentially very subtle, the precision and multielement analysis provided by NAA are considered essential for this project. The purpose of the analysis is to link ceramic compositional groups to raw clay sources in order to address issues of production and exchange.

  7. Fiscal years 1993 and 1994 decontamination and decommissioning activities photobriefing book for the Argonne National Laboratory-East Site, Technology Development Division, Decontamination and Decommissioning Projects Department

    SciTech Connect

    1995-12-31

    This photobriefing book describes the ongoing decontamination and decommissioning projects at the Argonne National Laboratory (ANL)-East Site near Lemont, Illinois. The book is broken down into three sections: introduction, project descriptions, and summary. The introduction elates the history and mission of the Decontamination and Decommissioning (D and D) Projects Department at ANL-East. The second section describes the active ANL-East D and D projects, giving a project history and detailing fiscal year (FY) 1993 and FY 1994 accomplishments and FY 1995 goals. The final section summarizes the goals of the D and D Projects Department and the current program status. The D/D projects include the Experimental Boiling Water Reactor, Chicago Pile-5 Reactor, that cells, and plutonium gloveboxes. 73 figs.

  8. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 6 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  9. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 3 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  10. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 5 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  11. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 2 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  12. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 4 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  13. A Historical Evaluation of the U12t Tunnel, Nevada Test Site, Nye County, Nevada, Volume 1 of 6

    SciTech Connect

    Harold Drollinger; Robert C. Jones; and Thomas F. Bullard; Desert Research Institute, Laurence J. Ashbaugh, Southern Nevada Courier Service and Wayne R. Griffin, Stoller-Navarro Joint Venture

    2009-02-01

    This report presents a historical evaluation of the U12t Tunnel on the Nevada Test Site in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office and the U.S. Department of Defense, Defense Threat Reduction Agency (DTRA). The U12t Tunnel is one of a series of tunnels used for underground nuclear weapons effects tests on the east side of Rainier and Aqueduct Mesas. Six nuclear weapons effects tests, Mint Leaf, Diamond Sculls, Husky Pup, Midas Myth/Milagro, Mighty Oak, and Mission Ghost, and one high explosive test, SPLAT, were conducted within the U12t Tunnel from 1970 to 1987. All six of the nuclear weapons effects tests and the high explosive test were sponsored by DTRA. Two conventional weapons experiments, Dipole Knight and Divine Eagle, were conducted in the tunnel portal area in 1997 and 1998. These experiments were sponsored by the Defense Special Weapons Agency. The U12t Tunnel complex is composed of the Portal and Mesa Areas and includes an underground tunnel with a main access drift and nine primary drifts, a substantial tailings pile fronting the tunnel portal, a series of discharge ponds downslope of the tailings pile, and two instrumentation trailer parks and 16 drill holes on top of Aqueduct Mesa. A total of 89 cultural features were recorded: 54 at the portal and 35 on the mesa. In the Portal Area, cultural features are mostly concrete pads and building foundations; other features include the portal, rail lines, the camel back, ventilation and cooling system components, communication equipment, and electrical equipment. On the mesa are drill holes, a few concrete pads, a loading ramp, and electrical equipment.

  14. The Laramide Mesa formation and the Ojo de Agua caldera, southeast of the Cananea copper mining district, Sonora, Mexico

    USGS Publications Warehouse

    Cox, Dennis P.; Miller, Robert J.; Woodbourne, Keith L.

    2006-01-01

    The Mesa Formation extends from Cananea, Mexico, southeast to the Sonora River and is the main host rock of Laramide porphyry copper deposits in the Cananea District and at the Alacran porphyry prospect to the east. The Mesa consists of two members-a lower andesite and an upper dacite. The lowest part of the dacite member is a crystal tuff about 100 m thick. This tuff is the outfall of a caldera centered near the village of Ojo de Agua, dated by 40Ar/39Ar at 65.8 Ma ?0.4. The Ojo de Agua Caldera is about 9 km in diameter and is filled by a light gray biotite dacite tuff with abundant flattened pumice fragments. The volume of the caldera is estimated to be 24 km3.

  15. MESA: A 3-D Eulerian hydrocode for penetration mechanics studies

    SciTech Connect

    Mandell, D.A.; Holian, K.S.; Henninger, R.

    1991-01-01

    We describe an explicit, finite-difference hydrocode, called MESA, and compare calculations to metal and ceramic plate impacts with spall and to Taylor cylinder tests. The MESA code was developed with support from DARPA, the Army and the Marine Corps for use in armor/anti-armor problems primarily, but the code has been used for a number of other applications. MESA includes 2-D and 3-D Eulerian hydrodynamics, a number of material strength and fracture models, and a programmed burn high explosives model. 15 refs., 4 figs.

  16. Spatial and temporal variability of snow chemical composition and accumulation rate at Talos Dome site (East Antarctica).

    PubMed

    Caiazzo, Laura; Becagli, Silvia; Frosini, Daniele; Giardi, Fabio; Severi, Mirko; Traversi, Rita; Udisti, Roberto

    2016-04-15

    Five snow pits and five firn cores were sampled during the 2003-2004 Italian Antarctic Campaign at Talos Dome (East Antarctica), where a deep ice core (TALDICE, TALos Dome Ice CorE, 1650m depth) was drilled in 2005-2008 and analyzed for ionic content. Particular attention is spent in applying decontamination procedures to the firn cores, as core sections were stored for approximately 10years before analysis. By considering the snow pit samples to be unperturbed, the comparison with firn core samples from the same location shows that ammonium, nitrate and MSA are affected by storage post-depositional losses. All the other measured ions are confirmed to be irreversibly deposited in the snow layer. The removal of the most external layers (few centimeters) from the firn core sections is proved to be an effective decontamination procedure. High-resolution profiles of seasonal markers (nitrate, sulfate and MSA) allow a reliable stratigraphic dating and a seasonal characterization of the samples. The calculated mean accumulation-rate values range from 70 to 85mmw.e.year(-1), in the period 2003-1973 with small differences between two sectors: 70-74mmw.e.year(-1) in the NNE sector (spanning 2003-1996years) and 81-92mmw.e.year(-1) in the SSW sector (spanning 2003-1980years). This evidence is interpreted as a coupled effect of wind-driven redistribution processes in accumulation/ablation areas. Statistical treatment applied to the concentration values of the snow pits and firn cores samples collected in different points reveals a larger temporal variability than spatial one both in terms of concentration of chemical markers and annual accumulation. The low spatial variability of the accumulation rate and chemical composition measured in the five sites demonstrates that the TALDICE ice core paleo-environmental and paleo-climatic stratigraphies can be considered as reliably representative for the Talos Dome area. PMID:26849319

  17. Magnesium isotopic compositions of altered oceanic basalts and gabbros from IODP site 1256 at the East Pacific Rise

    NASA Astrophysics Data System (ADS)

    Huang, Jian; Ke, Shan; Gao, Yongjun; Xiao, Yilin; Li, Shuguang

    2015-08-01

    To investigate the behaviour of Mg isotopes during alteration of oceanic crust and constrain the Mg isotopic compositions of the altered oceanic crust (AOC), high-precision Mg isotope analyses have been conducted on forty-four altered basalts and gabbros recovered from IODP site 1256, which represent the carbonate-barren AOC formed at the East Pacific Rise (EPR). These samples were altered by interaction of seawater-derived fluids with oceanic crust at different temperatures and water/rock ratios. With the exception of one sample that has a slightly heavier Mg isotopic composition (δ26Mg = 0.01 ± 0.08‰), all the other samples have relatively homogenous and mantle-like Mg isotopic compositions, with δ26Mg ranging from - 0.36 to - 0.14‰ (an average value of - 0.25 ± 0.11‰, 2SD, n = 43). This suggests that limited Mg isotope fractionation occurred during alteration of oceanic crust at the EPR at bulk rock scale, irrespective of highly variable alteration temperatures and variable water/rock ratios. Thus, our study suggests that the offset of δ26Mg values between seawater and global runoff dominantly results from the formation of marine dolomite as a sink for Mg. The mantle-like Mg isotopic composition further indicates that recycling of carbonate-barren AOC would not result in Mg isotope heterogeneity of the mantle at global scale. Consequently, the light Mg isotopic compositions of the mantle at local scale must result from incorporation of recycled Mg isotopically light carbonates.

  18. Size-resolved source apportionment of ambient particles by positive matrix factorization at Gosan background site in East Asia

    NASA Astrophysics Data System (ADS)

    Han, J. S.; Moon, K. J.; Lee, S. J.; Kim, Y. J.; Ryu, S. Y.; Cliff, S. S.; Yi, S. M.

    2006-01-01

    Size- and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 29 March to 29 May in 2002 at Gosan, Jeju Island, Korea, which is one of the representative background sites in East Asia. These samples were analyzed using synchrotron X-ray fluorescence for 3-h average concentrations of 19 elements consisting of S, Si, Al, Fe, Ca, Cl, Cu, Zn, Ti, K, Mn, Pb, Ni, V, Se, As, Rb, Cr, Br. The size-resolved data sets were then analyzed using the positive matrix factorization (PMF) technique in order to identify possible sources and estimate their contribution to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Fifteen sources were resolved in eight size ranges (0.07~12 μm) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil heating furnace, residual oil fired boiler, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, copper smelter and volcanic emission. PMF analysis of size-resolved source contributions showed that natural sources represented by local soil, sea salt and continental soil contributed about 79% to the predicted primary particulate matter (PM) mass in the coarse size range (1.15~12 μm). On the other hand, anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 60% in the fine size range (0.56~2.5 μm). The diesel vehicle source contributed the most in the ultra-fine size range (0.07~0.56 μm) and was responsible for about 52% of the primary PM mass.

  19. Geohydrology of Pahute Mesa-3 test well, Nye County, Nevada

    SciTech Connect

    Kilroy, K.C.; Savard, C.S.

    1997-02-01

    The Pahute Mesa-3 test well is on Pahute Mesa about 3 miles west of the Nevada Test Site and 20 miles northeast of Oasis Valley near Beatty, Nevada. The well was drilled for the U.S. Department of Energy Radionuclide Migration Program to monitor conditions near the western edge of the Nevada Test Site. The well was drilled with conventional rotary methods and an air-foam drilling fluid to a depth of 3,019 feet. A 10.75-inch diameter steel casing was installed to a depth of 1,473 feet. The test well penetrates thick units of non-welded to partly welded ash-flow and air-fall tuff of Tertiary age with several thin layers of densely welded tuff, rhyolite and basalt flows, and breccia. Geophysical logs indicate that fractures are significant in the Tiva Canyon Tuff of the Paintbrush Group and this was confirmed by high flow in this unit during a borehole-flow survey. The geophysical logs also show that the effective porosity in tuffaceous units ranges from 19 to 38 percent and averages 30 percent, and the total porosity ranges from 33 to 55 percent and averages 42 percent. The measured temperature gradient of 1.00 degree Celsius per 100 feet is steep, but is similar to that of other nearby wells, one of which penetrates a buried granite intrusion. Injection tests for six intervals of the well yielded transmissivities that ranged from 3.1 x 10{sup -3} to 25 feet squared per day and hydraulic conductivities that ranged from 6 x 10{sup -5} to 0.12 foot per day. The sum of the transmissivities is 28 feet squared per day and the geometric mean of hydraulic conductivity is 1.7 x 10{sup -3} foot per day. Estimates of storage coefficient range from 2.1 x 10{sup -5} to 3.8 x 10{sup -3}, indicating that the aquifer responded to the injection tests in a confined manner. An aquifer test produced a drawdown of 78 feet during 31 hours of testing at 169 gallons per minute.

  20. Completion Report for Well ER-12-4, Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain (includes Errata Sheet)

    SciTech Connect

    U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Bechtel Nevada

    2006-05-01

    Well ER-12-4 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. This well was drilled in May 2005, as part of a hydrogeologic investigation program for the Rainier Mesa-Shoshone Mountain Corrective Action Unit in the north-central portion of the Nevada Test Site. The well is located on Rainier/Aqueduct Mesa, northwest of Yucca Flat, within Area 12 of the Nevada Test Site. The well provided information regarding the radiological and physical environment near underground nuclear tests conducted in U12t Tunnel, information on the pre-Tertiary rocks in the area, and depth to the regional water table.

  1. Overview of the Grand Junction Office from Bluff east of ...

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

    Overview of the Grand Junction Office from Bluff east of facility. Note Buildings #35. #33 and #31A in lower left of photograph. VIEW WEST - Department of Energy, Grand Junction Office, 2597 B3/4 Road, Grand Junction, Mesa County, CO

  2. CHARACTERIZATION OF MERCURY CONTAMINATION AT THE EAST FORK POPLAR CREEK SITE, OAK RIDGE, TENNESSEE: A CASE STUDY

    EPA Science Inventory

    Historic accidental release of mercury-contaminated material associated with nuclear weapons production at East Fork Poplar Creek (EFPC) resulted in stream and floodplain contamination. he EFPC is designated as an Oak Ridge Reservation (ORR) operable unit under the Comprehensive ...

  3. Final predictions of ambient conditions along the east-west crossdrift using the 3-D UZ site-scale model. Level 4 milestoneSP33ABM4.

    SciTech Connect

    Ritcey, A.C.; Sonnenthal, E.L.; Wu, Y.S.; Haukwa, C.; Bodvarsson,G.S.

    1998-03-01

    In 1998, the Yucca Mountain Site Characterization Project (YMP) is expected to continue construction of an East-West Cross Drift. The 5-meter diameter drift will extend from the North Ramp of the Exploratory Studies Facility (ESF), near Station 19+92, southwest through the repository block, and over to and through the Solitario Canyon Fault. This drift is part of a program designed to enhance characterization of Yucca Mountain and to complement existing surface-based and ESF testing studies. The objective of this milestone is to use the three-dimensional (3-D) unsaturated zone (UZ) site-scale model to predict ambient conditions along the East-West Cross Drift. These predictions provide scientists and engineers with a priori information that can support design and construction of the East-West Cross Drift and associated testing program. The predictions also provide, when compared with data collected after drift construction, an opportunity to test and verify the calibration of the 3-D UZ site-scale model.

  4. Chemical composition and mass size distribution of PM1 at an elevated site in central east China

    NASA Astrophysics Data System (ADS)

    Zhang, Y. M.; Zhang, X. Y.; Sun, J. Y.; Hu, G. Y.; Shen, X. J.; Wang, Y. Q.; Wang, T. T.; Wang, D. Z.; Zhao, Y.

    2014-11-01

    Size-resolved aerosol chemical compositions were measured continuously for 1.5 years from June 2010 to January 2012 with an aerosol mass spectrometer (AMS) to characterize the mass and size distributions (MSDs) of major chemical components in submicron particles (approximately PM1) at Mountain Tai (Mt. Tai), an elevated site in central east China. The annual mean mass concentrations of organic, sulfate, nitrate, ammonium, and chloride were 11.2, 9.2, 7.2, 5.8, and 0.95 μg m-3, respectively, which are much higher than those at most mountain sites in the USA and Europe, but lower than those at the nearby surface rural sites in China. A clear seasonality was observed for all major components throughout the study, with low concentration in fall and high in summer, and is believed to be caused by seasonal variations in planetary boundary layer (PBL) height, near surface pollutant concentrations and regional transport processes. Air masses were classified into categories impacted by PBL, lower free troposphere (LFT), new particle formation (NPF), in-cloud processes, and polluted aerosols. Organics dominated the PM1 mass during the NPF episodes, while sulfate contributed most to PM1 in cloud events. The average MSDs of particles between 30 and 1000 nm during the entire study for organics, sulfate, nitrate, and ammonium were approximately log-normal with mass median diameters (MMDs) of 539, 585, 542, and 545 nm, respectively. These values are slightly larger than those observed at ground sites within the North China Plain (NCP), likely due to the relative aged and well-mixed aerosol masses at Mt. Tai. There were no obvious differences in MMDs during the PBL, LFT, in-cloud and polluted episodes, but smaller MMDs, especially for organics, were observed during the NPF events. During the PBL, NPF, and polluted episodes, organics accounted for major proportions at smaller modes, and reached 70% at 100-200 nm particles in the polluted events. In cloud episodes, inorganics contributed 70% to the whole size range dominated by sulfate, which contributed 40% to small particles (100-200 nm), while organics occupied 20%, indicating that sulfate is a critical chemical component in cloud formation. Seven clusters of air masses were classified based on 72 h back-trajectory analysis. The majority of the regionally dispersed aerosols were found to be contributed from short distance mixed aerosols, mostly originated from the south with organics and sulfate as major components. Air masses from long range transport always brought clean and dry aerosols which resulted in low concentrations at Mt. Tai. AMS-PMF (positive matrix factorization) was employed to resolve the subtype of organics. Oxygenic organics aerosols (OAs) occupied 49, 56, 51, and 41% of OAs in the four seasons respectively, demonstrating that most OA were oxidized in summer due to strong photochemical reactions. Biomass burning OAs (BBOAs) accounted for 34% of OA in summer, mainly from field burning of agriculture residues, and coal combustion OAs (CCOAs) accounted for 22% of OA in winter from heating.

  5. Coop Creek Bridge with Checkerboard Mesa in background, historic photograph, ...

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

    Co-op Creek Bridge with Checkerboard Mesa in background, historic photograph, no date, Zion National Park collection - Zion-Mount Carmel Highway, Co-op Creek Bridge, Spanning Co-op Creek, Springdale, Washington County, UT

  6. MESA: Supporting Software Development with Coordinated Scientific Input

    NASA Astrophysics Data System (ADS)

    Diaz, R. I.

    2015-09-01

    The Mission Engineering and Science Analysis (MESA) group provides dedicated scientific support to the major software development projects at STScI. Facilitating the communication between scientists and developers has proven beneficial to utilize efficiently the resources and to meet, in a timely manner, the scientific objectives of the mission offices at STScI. We present an overview of the MESA group and highlight the projects we are currently working on.

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

    USGS Publications Warehouse

    Murray, Louis C., Jr.

    2010-01-01

    Multivariate linear regression analyses were used to define the relations of water levels in the Upper Floridan aquifer (UFA) and surficial aquifer system (SAS) to anthropogenic and meteorological stressors between 1995 and 2007 at two monitoring well sites (Charlotte Street and Lake Oliver) in east-central Florida. Anthropogenic stressors of interest included municipal and agricultural groundwater withdrawals, and application of reclaimed-water to rapid-infiltration basins (source of aquifer recharge). Meteorological stressors included precipitation and potential evapotranspiration. Overall, anthropogenic and meteorological stressors accounted for about 40 to 89 percent of the variance in UFA and SAS groundwater levels and water-level changes. While mean monthly water levels were better correlated with monthly stressor values, changes in UFA and SAS water levels were better correlated with changes in stressor values. Water levels and water-level changes were influenced by system persistence as the moving-averaged values of both stressor types, which accounted for the influence of the previous month(s) conditions, consistently yielded higher adjusted coefficients of determination (R2 adj) values than did single monthly values. While monthly water-level changes tend to be influenced equally with both stressors across the hydrologically averaged 13-year period, changes were more influenced by one stressor or the other seasonally and during extended wet and dry periods. Seasonally, UFA water-level changes tended to be more influenced by anthropogenic stressors than by meteorological stressors, while changes in SAS water levels tended to be more influenced by meteorological stressors. During extended dry periods (12 months or greater), changes in UFA water levels at Charlotte Street were more affected by anthropogenic stressors than by meteorological stressors, while changes in SAS levels were more affected by meteorological stressors. At Lake Oliver, changes in both UFA and SAS water levels were better correlated with meteorological stressors for all but the wet period between April 1995 and April 1996. Interestingly, changes in both UFA and SAS water levels at Charlotte Street were also better correlated with anthropogenic stressors during a similar wet period between April 1995 and June 1996 when substantive reductions in groundwater withdrawals resulted in appreciable recovery of both UFA and SAS water levels. The regional effects of anthropogenic stressors had limited influence on water-level changes at Charlotte Street and virtually no influence on changes at Lake Oliver. When regressed against the 2.2 Mgal/d (million gallons per day) of municipal withdrawals located within 2 miles of the Charlotte Street site, water-level changes were influenced solely by precipitation and potential evapotranspiration. At a radius of 2.5 miles, however, where cumulative withdrawals totaled about 9.5 Mgal/d, water-level changes were equally influenced by both anthropogenic and meteorological stressors. Withdrawals located at distances of greater than 3 miles from this site had no appreciable effect on relations between water-level changes and these stressors. At Lake Oliver, changes in UFA water levels were equally influenced by both stressors regardless of distance, while changes in SAS levels were more influenced by meteorological stressors at all distances.

  8. Simple estimation of fastest preferential contaminant travel times in the unsaturated zone: application to Rainier Mesa and Shoshone Mountain, Nevada

    NASA Astrophysics Data System (ADS)

    Ebel, B. A.; Nimmo, J. R.

    2010-06-01

    Simulating contaminant transport in unsaturated zones with sparse hydraulic property information is a difficult, yet common, problem. When contaminant transport may occur via preferential flow, simple modeling approaches can provide predictions of interest, such as the first arrival of contaminant, with minimal site characterization. The conceptual model for unsaturated zone flow at two areas within the Nevada Test Site, Rainier Mesa and Shoshone Mountain, establishes the possibility of preferential flow through lithologies between potential radionuclide sources and the saturated zone. Lithology, saturated or near-saturated conditions in portions of the rock matrix, and relatively high recharge rates may act in concert at Rainier Mesa to promote preferential flow, despite the semi-arid climate. After identifying preferential flow as a possible contaminant transport process at Rainier Mesa and Shoshone Mountain, we apply a simple model to estimate fastest unsaturated travel times for conservatively-transported radionuclides to initially reach the saturated zone. Preferential flow travel times at Rainier Mesa are tens to hundreds of years for non-ponded water sources and one to two months for continuously-ponded water sources. If preferential flow occurs at Shoshone Mountain, the fastest travel times are approximately twice the Rainier Mesa estimates. A siliceous rock unit is present at Shoshone Mountain that may provide a barrier to preferential flow; if so, estimated transport times increase to more than a thousand years. Our analysis of unsaturated transport of radionuclides via preferential flow, using a relatively simple model, suggests that contaminated locations associated with continuously-supplied water sources, such as effluent ponds and water-filled tunnels, may have significantly shorter radionuclide travel times than locations not associated with such sources. The simple approach demonstrated here for estimating travel times can be useful in situations where predictions are needed by managers for the fastest arrival of contaminants, yet budgetary or time constraints preclude more rigorous analysis, and when additional model estimates are needed for comparison (i.e. model abstraction).

  9. MESA: Mercator scheduler and archive system

    NASA Astrophysics Data System (ADS)

    Merges, Florian; Prins, Saskia; Pessemier, Wim; Raskin, Gert; Perez Padilla, Jesus; Van Winckel, Hans; Aerts, Conny

    2012-09-01

    We have developed an observing scheduling and archive system for the 1.2 meter Mercator Telescope. The goal was to optimize the specific niche of this modern small telescope in observational astrophysics: the building-up of long-term time series of photometric or high-resolution spectroscopic data with appropriate sampling for any given scientific program. This system allows PIs to easily submit their technical requirements and keep track of the progress of the observing programmes. The scheduling system provides the observer with an optimal schedule for the night which takes into account the current observing conditions as well as the priorities and requirements of the programmes in the queue. The observer can conveniently plan an observing night but also quickly adapt it to changing conditions. The archiving system automatically processes new files as they are created, including reduced data. It extracts the metadata and performs the normalization. A user can query, inspect and retrieve observing data. The progress of individual programmes, including timeline and reduced data plots can be seen at any time. Our MESA project is based on free and open source software (FOSS) using the Python programming language. The system is fully integrated with the Mercator Observing Control System1 (MOCS).

  10. Extracting the MESA SR4000 calibrations

    NASA Astrophysics Data System (ADS)

    Charleston, Sean A.; Dorrington, Adrian A.; Streeter, Lee; Cree, Michael J.

    2015-05-01

    Time-of-flight range imaging cameras are capable of acquiring depth images of a scene. Some algorithms require these cameras to be run in `raw mode', where any calibrations from the off-the-shelf manufacturers are lost. The calibration of the MESA SR4000 is herein investigated, with an attempt to reconstruct the full calibration. Possession of the factory calibration enables calibrated data to be acquired and manipulated even in "raw mode." This work is motivated by the problem of motion correction, in which the calibration must be separated into component parts to be applied at different stages in the algorithm. There are also other applications, in which multiple frequencies are required, such as multipath interference correction. The other frequencies can be calibrated in a similar way, using the factory calibration as a base. A novel technique for capturing the calibration data is described; a retro-reflector is used on a moving platform, which acts as a point source at a distance, resulting in planar waves on the sensor. A number of calibrations are retrieved from the camera, and are then modelled and compared to the factory calibration. When comparing the factory calibration to both the "raw mode" data, and the calibration described herein, a root mean squared error improvement of 51:3mm was seen, with a standard deviation improvement of 34:9mm.

  11. Feasibility Study of Biopower in East Helena, Montana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Moriarty, K.

    2013-02-01

    The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to reuse contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former American Smelting and Refining Company (Asarco) smelter in East Helena, Montana, was selected for a feasibility study under the initiative. Biomass was chosen as the renewable energy resource based on the wood products industry in the area. Biopower was selected as the technology based on Montana's renewable portfolio standard (RPS) requiring utilities to purchase renewable power.

  12. Analysis of radiocarbon dates of an archaeological site in the Russian Far East: The marine reservoir effect as seen on charred remains on pottery

    NASA Astrophysics Data System (ADS)

    Kunikita, Dai; Yoshida, Kunio; Miyazaki, Yumiko; Saito, Keita; Endo, Aya; Matsuzaki, Hiroyuki; Ito, Shinji; Kobayashi, Tatsuo; Fujimoto, Tsuyoshi; Kuznetsov, A. M.; Krupyanko, A. A.; Tabarev, A. M.

    2007-06-01

    In order to obtain precise and accurate calibrated radiocarbon chronologies for archaeological sites, it is necessary to determine the provenance of the carbon material being dated. Of particular note is determining the provenance and radiocarbon age of charcoal remains on pottery. In this context, we discuss the decipherment of dates on the Ustinovka-8 site in the Russian Far East. Using δ13C, δ15N and C:N it is possible to ascribe charcoal provenance to terrestrial and marine origins. Our data show radiocarbon age difference that are clearly associated with carbon origin, and a maximum estimated ΔR of approximately 400 years during the Zaisanovskaya culture, 4400 cal BP. A combination of pottery analysis and 14C dating at this site determined the Zaisanovskaya cultural period to be 4000-5000 cal BP, the Boismanskaya and the Late Rudninskaya cultural period 5800-6500 cal BP, and the Early Rudninskaya cultural period of 6800-7100 cal BP.

  13. A Computationally Efficient Multicomponent Equilibrium Solver for Aerosols (MESA)

    SciTech Connect

    Zaveri, Rahul A.; Easter, Richard C.; Peters, Len K.

    2005-12-23

    This paper describes the development and application of a new multicomponent equilibrium solver for aerosol-phase (MESA) to predict the complex solid-liquid partitioning in atmospheric particles containing H+, NH4+, Na+, Ca2+, SO4=, HSO4-, NO3-, and Cl- ions. The algorithm of MESA involves integrating the set of ordinary differential equations describing the transient precipitation and dissolution reactions for each salt until the system satisfies the equilibrium or mass convergence criteria. Arbitrary values are chosen for the dissolution and precipitation rate constants such that their ratio is equal to the equilibrium constant. Numerically, this approach is equivalent to iterating all the equilibrium reactions simultaneously with a single iteration loop. Because CaSO4 is sparingly soluble, it is assumed to exist as a solid over the entire RH range to simplify the algorithm for calcium containing particles. Temperature-dependent mutual deliquescence relative humidity polynomials (valid from 240 to 310 K) for all the possible salt mixtures were constructed using the comprehensive Pitzer-Simonson-Clegg (PSC) activity coefficient model at 298.15 K and temperature-dependent equilibrium constants in MESA. Performance of MESA is evaluated for 16 representative mixed-electrolyte systems commonly found in tropospheric aerosols using PSC and two other multicomponent activity coefficient methods – Multicomponent Taylor Expansion Method (MTEM) of Zaveri et al. [2004], and the widely-used Kusik and Meissner method (KM), and the results are compared against the predictions of the Web-based AIM Model III or available experimental data. Excellent agreement was found between AIM, MESA-PSC, and MESA-MTEM predictions of the multistage deliquescence growth as a function of RH. On the other hand, MESA-KM displayed up to 20% deviations in the mass growth factors for common salt mixtures in the sulfate-poor cases while significant discrepancies were found in the predicted multistage deliquescence points as well as mass growth factors for the sulfate-rich systems. The MESA-MTEM configuration required only 5 to 10 single-level iterations to obtain the equilibrium solution for ~44% of the 328 multiphase problems solved in the 16 test cases at RH values ranging between 20% and 90%, while ~85% of the problems solved required less than 20 iterations. Based on the accuracy and computational efficiency considerations, the MESA-MTEM configuration is attractive for use in 3-D aerosol/air quality models.

  14. Triplet superconductivity in oxide ferromagnetic interlayer of mesa-structure

    NASA Astrophysics Data System (ADS)

    Ovsyannikov, G. A.; Y Constantinian, K.; Sheerman, A. E.; Shadrin, A. V.; Kislinski, Yu V.; Khaydukov, Yu N.; Mustafa, L.; Kalabukhov, A.; Winkler, D.

    2015-03-01

    We present experimental data on Nb-Au/La0.7Sr0.3MnO3/SrRuO3/YBa2Cu3O7-δ mesa- structure with in plane linear size 10÷50 μm. The mesa-structures were patterned from the epitaxial heterostructures fabricated by pulsed laser ablation and magnetron sputtering. Superconducting critical current was observed for mesa-structures with the interlayer thicknesses up to 50 nm. In the mesa-structures with just one, either La0.7Sr0.3MnO3 or SrRuO3 interlayer with a thickness larger than 10 nm no superconducting current was observed. The registered superconducting current for the mesa-structures with a thinner interlayer is attributed to pinholes. Obtained results are discussed in terms of superconducting long-range triplet generation at interfaces of superconductor and a composite ferromagnet consisting of ferromagnetic materials with non-collinear magnetization.

  15. Assessment of potential migration of radionuclides and trace elements from the White Mesa uranium mill to the Ute Mountain Ute Reservation and surrounding areas, southeastern Utah

    USGS Publications Warehouse

    Naftz, David L.; Ranalli, Anthony J.; Rowland, Ryan C.; Marston, Thomas M.

    2011-01-01

    In 2007, the Ute Mountain Ute Tribe requested that the U.S. Environmental Protection Agency and U.S. Geological Survey conduct an independent evaluation of potential offsite migration of radionuclides and selected trace elements associated with the ore storage and milling process at an active uranium mill site near White Mesa, Utah. Specific objectives of this study were (1) to determine recharge sources and residence times of groundwater surrounding the mill site, (2) to determine the current concentrations of uranium and associated trace elements in groundwater surrounding the mill site, (3) to differentiate natural and anthropogenic contaminant sources to groundwater resources surrounding the mill site, (4) to assess the solubility and potential for offsite transport of uranium-bearing minerals in groundwater surrounding the mill site, and (5) to use stream sediment and plant material samples from areas surrounding the mill site to identify potential areas of offsite contamination and likely contaminant sources. The results of age-dating methods and an evaluation of groundwater recharge temperatures using dissolved-gas samples indicate that groundwater sampled in wells in the surficial aquifer in the vicinity of the mill is recharged locally by precipitation. Tritium/helium age dating methods found a "modern day" apparent age in water samples collected from springs in the study area surrounding the mill. This apparent age indicates localized recharge sources that potentially include artificial recharge of seepage from constructed wildlife refuge ponds near the mill. The stable oxygen isotope-ratio, delta oxygen-18, or δ(18O/16O), known as δ18O, and hydrogen isotope-ratio, delta deuterium, or δ(2H/1H), known as δD, data indicate that water discharging from Entrance Spring is isotopically enriched by evaporation and has a similar isotopic fingerprint as water from Recapture Reservoir, which is used as facilities water on the mill site. Water from Recapture Reservoir also is used to irrigate fields surrounding the town of Blanding and infiltration of this irrigated water also could contribute to the enriched isotopic fingerprint observed for Entrance Spring. Similarities in the delta sulfur-34sulfate values in water samples from the wildlife ponds and tailings cells indicate a potential contaminant linkage between the tailings cells and the refuge ponds that could be related to wind carried (eolian) transport of aerosols from the tailings cells. To date (2010), neither the delta sulfur-34sulfate nor the delta oxygen-18sulfate values measured in the wells and springs surrounding the uranium mill site have an isotopic signature characteristic of water from the tailings cells. Except for Entrance Spring and Mill Spring, all groundwater samples collected at down-gradient sample sites during this study had dissolved-uranium concentrations in the range expected for naturally-occurring uranium. The uranium-isotope data indicate that the mill is not a source of uranium in the groundwater in the unconfined-aquifer at any site monitored during the study, with the possible exception of Entrance Spring. The uranium-234 to uranium-238 concentration activity ratios measured in water samples collected at Entrance Spring, and the decrease in this ratio associated with an increase in the concentration of dissolved uranium indicate potential mixing of uranium ore with groundwater at the spring through eolian transport of small particles from ore-storage pads and uncovered ore trucks, with subsequent deposition in the Entrance Spring drainage, followed by dissolution in the unconfined groundwater. The isotopic values of uranium found in other water samples collected during the study do not appear to be related to uranium ore deposits. Water samples collected from Entrance Spring contained the highest median uranium concentrations relative to water samples collected from the other wells and springs monitored during the study. Water samples collected from Entrance Spring also contained elevated concentrations of selenium and vanadium. Sediment samples collected from three ephemeral drainages east of the uranium mill site (including Entrance Spring) contained uranium concentrations exceeding background values downwind of the predominant wind directions at the site. Sediment samples collected from ephemeral drainages on the south and west boundaries of the uranium mill site generally did not exceed background-uranium concentrations. Elevated concentrations of uranium and vanadium, indicating offsite transport, were found in plant tissue samples collected north-northeast, east, and south of the mill site, downwind of 2 Assessment of potential migration of radionuclides and trace elements from the White Mesa uranium mill the predominant wind directions at the site. The uranium and vanadium concentrations in plant tissue samples collected west of the uranium mill site were low. On the basis of the study results, consideration should be given to future monitoring programs in areas surrounding the uranium mill site to address current and future environmental concerns. These potential monitoring programs should consider (1) quarterly monitoring of major- and trace-element concentrations in selected springs and wells; (2) annual monitoring of Entrance Spring for uranium isotopes, delta sulfur-34sulfate, delta oxygen-18, and delta deuterium; (3) annual monitoring of background water quality at selected spring and monitoring well sites; (4) periodic sampling and chemical analyses of sagebrush in areas east of the uranium mill site coupled with off-site fugitive dust monitoring; (5) installation of a new monitoring well upgradient from the East and West wells; (6) the addition of non-routine chemical constituents to ongoing monitoring programs within the uranium mill site that could provide additional insight(s) into potential contaminant sources and processes; and (7) archiving future monitoring data into a maintained database that is easily accessible to all project stakeholders.

  16. MESA - A new approach to low cost scientific spacecraft

    NASA Astrophysics Data System (ADS)

    Keyes, G. W.; Case, C. M.

    1982-09-01

    Today, the greatest obstacle to science and exploration in space is its cost. The present investigation is concerned with approaches for reducing this cost. Trends in the scientific spacecraft market are examined, and a description is presented for the MESA space platform concept. The cost drivers are considered, taking into account planning, technical aspects, and business factors. It is pointed out that the primary function of the MESA concept is to provide a satellite system at the lowest possible price. In order to reach this goal an attempt is made to benefit from all of the considered cost drivers. It is to be tried to work with the customer early in the mission analysis stage in order to assist in finding the right compromise between mission cost and return. A three phase contractual arrangement is recommended for MESA platforms. The phases are related to mission feasibility, specification definition, and design and development. Modular kit design promotes flexibility at low cost.

  17. Recruitment in Clinical Versus Community-Based Sites for a Pilot Youth Diabetes Prevention Program, East Harlem, New York, 2011–2012

    PubMed Central

    Townsend, Kenya; Arniella, Guedy; Goytia, Crispin; Horowitz, Carol R.

    2016-01-01

    Introduction Little is known about successful strategies for recruitment of youth for research. The objective of this study was to compare clinical sites with community sites in the recruitment of teenagers for a new youth diabetes prevention program in East Harlem, New York. Methods We assessed diabetes risk for youth (aged 13–19 y) by measuring body mass index (BMI). We then screened overweight and obese youth for prediabetes using oral glucose tolerance testing, had them complete a health and lifestyle survey, and enrolled prediabetic youth into peer-led workshops. The recruitment strategies were 1) clinical referrals and 2) screenings at community sites. We compared the number of adolescents screened, the proportion eligible for testing, the proportion diagnosed with prediabetes, baseline characteristics, and the retention rates between those recruited in clinical and community sites. Results In 3 months, we completed BMI screening for 156 adolescents from community sites and 30 from clinical sites. Overall, 47% were at risk for diabetes on the basis of BMI, and 63% returned for diabetes testing; 35% had prediabetes, and 1 teenager had diabetes. Clinical sites yielded higher rates of diabetes risk on the basis of BMI and higher rates of return for screening and diagnosed prediabetes. Although demographics and BMI did not vary by recruitment site, we found differences in behaviors, self-efficacy, body image, and social support. There were no differences by recruitment site in workshop enrollment or completion or return for follow-up. Conclusion Both recruitment strategies were successful, and participants from both groups had high rates of undiagnosed prediabetes. Our approach allowed access to more adolescents and opportunities for education about diabetes in the community. PMID:26820046

  18. Modeling edge effects of mesa diodes for silicon photovoltaics

    NASA Astrophysics Data System (ADS)

    Appel, Jesse S.

    A mesa diode has been modeled and its performance under dark and illuminated conditions has been simulated using a commercial finite element software package. These simulations have led to a determination of the self-consistent solution to the continuity equations for electrons and holes using the steady-state drift-diffusion model for carrier dynamics coupled with electric potential determined from Poisson's equation. The purpose of these simulations has been to determine the influence of edge conditions on the overall performance of mesa diodes under dark and illuminated conditions. Mesa diode arrays are fabricated on crystalline silicon solar cells. They are an array of small area solar cells that are electrically isolated from one another. They can be probed to spatially measure the current density vs. voltage curves under dark and illuminated conditions. The underlying models of bulk and surface recombination mechanisms have been well established for crystalline silicon based semiconductor devices such as the mesa diode. However, the combination of these phenomena that occur during the simulation of the operation of the mesa diode results in a unique edge effect that can significantly change the overall performance of the mesa diode. In particular, the simulations performed show that the space charge region becomes extended along the vertical edge of the mesa diode due to the fixed positive surface charge. At the intersection of the vertical edge and step, a strong electric field is produced because it has a small convex radius of curvature. Depending on the sharpness of this intersection, the entire device can become significantly shunted. Simulations have been performed with a sharp corner and a smooth curve at the intersection of the vertical edge and the step. The use of a smooth curved transition results in significantly lower dark current density vs. voltage and a greater open circuit voltage and fill factor under illumination. Yet, even with a curved transition, the space charge region can extend approximately 100 microns into a 199.5 micron thick mesa diode, and have a bulk recombination rate that is two orders of magnitude greater than the rest of the device at low forward biases.

  19. Arias intensity assessment of liquefaction test sites on the east side of San Francisco Bay affected by the Loma Prieta, California, earthquake of 17 October 1989

    USGS Publications Warehouse

    Kayen, R.E.

    1997-01-01

    Abstract. Uncompacted artificial-fill deposits on the east side of San Francisco Bay suffered severe levels of soil liquefaction during the Loma Prieta earthquake of 17 October 1989. Damaged areas included maritime-port facilities, office buildings, and shoreline transportation arteries, ranging from 65 to 85 km from the north end of the Loma Prieta rupture zone. Typical of all these sites, which represent occurrences of liquefaction-induced damage farthest from the rupture zone, are low cone penetration test and Standard Penetration Test resistances in zones of cohesionless silty and sandy hydraulic fill, and underlying soft cohesive Holocene and Pleistocene sediment that strongly amplified ground motions. Postearthquake investigations at five study sites using standard penetration tests and cone penetration tests provide a basis for evaluation of the Arias intensity-based methodology for assessment of liquefaction susceptibility. ?? 1997 Kluwer Academic Publishers.

  20. Lights, camera and acoustics: Assessing macrobenthic communities at a dredged material disposal site off the North East coast of the UK

    NASA Astrophysics Data System (ADS)

    Birchenough, Silvana N. R.; Boyd, Sin E.; Coggan, Roger A.; Limpenny, David S.; Meadows, William J.; Rees, Hubert L.

    2006-10-01

    This study presents the results of a trial assessment based on a combination of sampling techniques at a dredged material disposal site located off the North East coast of the UK, over 2001 to 2004. The site was surveyed with a high-resolution sidescan sonar system producing a mosaic with 100% coverage of the survey area. Benthic communities and sediments were ground-truthed using a Hamon grab with a video camera. Additionally, the area was also sampled in 2003 with a Sediment Profile Imaging (SPI) camera, which complemented other techniques by providing in situ information on sediment quality, and biogenic activities. An assessment is made of the benefits of combining the results from conventional methods, principally using grab samples, with those from acoustic techniques and optical imaging devices to determine seafloor and macrobenthic conditions. This information has the potential to contribute to the enhancement of routine monitoring programmes within UK waters.

  1. National Wind Technology Center Site Environmental Assessment: Bird and Bat Use and Fatalities -- Final Report; Period of Performance: April 23, 2001 -- December 31, 2002

    SciTech Connect

    Schmidt, E.; Piaggio, A. J.; Bock, C. E.; Armstrong, D. M.

    2003-01-01

    This study was conducted to ascertain actual and potential impacts of wind turbines on populations of birds and bats at the National Wind Technology Center (NWTC) in northern Jefferson County, Colorado. The NWTC, which is part of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), is located on a mesa dominated by ungrazed grassland with isolated patches of ponderosa pine. Similar lands to the north and west are part of the city of Boulders open space system. Areas to the east and south are part of the Rocky Flats Environmental Technology Site.

  2. Two-dimensional velocity models for paths from Pahute Mesa and Yucca Flat to Yucca Mountain; Yucca Mountain Project

    SciTech Connect

    Walck, M.C.; Phillips, J.S.

    1990-11-01

    Vertical acceleration recordings of 21 underground nuclear explosions recorded at stations at Yucca Mountain provide the data for development of three two-dimensional crystal velocity profiles for portions of the Nevada Test Site. Paths from Area 19, Area 20 (both Pahute Mesa), and Yucca Flat to Yucca Mountain have been modeled using asymptotic ray theory travel time and synthetic seismogram techniques. Significant travel time differences exist between the Yucca Flat and Pahute Mesa source areas; relative amplitude patterns at Yucca Mountain also shift with changing source azimuth. The three models, UNEPM1, UNEPM2, and UNEYF1, successfully predict the travel time and amplitude data for all three paths. 24 refs., 34 figs., 8 tabs.

  3. San Diego Mesa College Student Satisfaction with Matriculation Services.

    ERIC Educational Resources Information Center

    San Diego Community Coll. District, CA. Research and Planning.

    A survey was conducted at Mesa College in San Diego, California to assess student satisfaction with the college's matriculation services. The in-class survey was administered over a 2-week period to a random sample of classes based on an 8% sample of the student population. The results of the study, based on a 78.7% response rate, included the…

  4. A Very High Order, Adaptable MESA Implementation for Aeroacoustic Computations

    NASA Technical Reports Server (NTRS)

    Dydson, Roger W.; Goodrich, John W.

    2000-01-01

    Since computational efficiency and wave resolution scale with accuracy, the ideal would be infinitely high accuracy for problems with widely varying wavelength scales. Currently, many of the computational aeroacoustics methods are limited to 4th order accurate Runge-Kutta methods in time which limits their resolution and efficiency. However, a new procedure for implementing the Modified Expansion Solution Approximation (MESA) schemes, based upon Hermitian divided differences, is presented which extends the effective accuracy of the MESA schemes to 57th order in space and time when using 128 bit floating point precision. This new approach has the advantages of reducing round-off error, being easy to program. and is more computationally efficient when compared to previous approaches. Its accuracy is limited only by the floating point hardware. The advantages of this new approach are demonstrated by solving the linearized Euler equations in an open bi-periodic domain. A 500th order MESA scheme can now be created in seconds, making these schemes ideally suited for the next generation of high performance 256-bit (double quadruple) or higher precision computers. This ease of creation makes it possible to adapt the algorithm to the mesh in time instead of its converse: this is ideal for resolving varying wavelength scales which occur in noise generation simulations. And finally, the sources of round-off error which effect the very high order methods are examined and remedies provided that effectively increase the accuracy of the MESA schemes while using current computer technology.

  5. Black Mesa Community School: Ten Years Later. A Progress Report.

    ERIC Educational Resources Information Center

    Black Mesa Community School Board, Inc., Chinle, AZ.

    The Black Mesa Community School, serving elementary school children in an isolated district of the Arizona Navajo reservation, represents the first step in Indian self-determination for area Navajos. The school is the result of community efforts begun in 1972 with a petition to operate a full-time school program for grades K-4 at Kitsilee.…

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

    USGS Publications Warehouse

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

    1991-01-01

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

  7. Assessment of the governance system for the management of the East Sea-Jung dumping site, Korea through analysis of heavy metal concentrations in bottom sediments

    NASA Astrophysics Data System (ADS)

    Song, Ki-Hoon; Choi, Ki-Young; Kim, Chang-Joon; Kim, Young-Il; Chung, Chang-Soo

    2015-12-01

    As with many countries, the Korea government has made a variety of efforts to meet the precautionary principle under the London Convention and Protocol acceded in 1994 and 2009. However, new strategies for the suitable marine dumping of waste materials have since been developed. In this study, the distribution and contamination of heavy metals including Al, Fe, Mn, Li, Co, Cr, Ni, Cu, Zn, As, Cd, Pb and Hg in bottom sediments were analyzed and compared to various criteria in order to evaluate the effectiveness of the management of the East Sea-Jung (ES-Jung) dumping site by the Korea government. The results indicate that the average metal concentrations were significantly lower than Effects Range Low (ERL) values, and generally similar to or lower than the Threshold Effect Levels (TEL) from the Sediment Quality Guidelinces (SQGs). According to analyses of various metal contamination indexes (Enrichment Factor: EF, Pollution Load Index: PLI and the Index of Geoaccumulation: Igeo), most areas were found to be uncontaminated by heavy metals with the exception of several moderately contaminated stations (ESJ 33, 54, 64 and ESJR 20). Heavy metal concentrations in areas grouped as G1, G2, DMDA, N-Ref and S-Ref which showed similar characteristics between 2007-2013 and 2014, were compared. Unexpectedly, most concentrations in the northern reference area (N-Ref) were much higher than those in the actual dumping areas (G1 and G2), may be due to the influences from nearby cities to the west of the ES-Jung site, rather than from the dumping site itself. Additionally, heavy metal concentrations in the dredged material dumping area (DMDA) were found to be low although they have slightly increased over time and those in the southern reference area (S-Ref) were found to have gradually decreased with year. The concentrations of most metals in the East Sea-Jung dumping site were similar to or less than those in the Earth's crust and approximately the same as those in continental sediments. As a result, this site can be considered as uncontaminated or slightly contaminated. This implies that the efforts made by the Korea government to manage and govern the dumping site through various policies, including `the focal point system', `the responsibility zones system' and `the principle of pollution causing party liability', have been successful.

  8. Groundwater, Surface-Water, and Water-Chemistry Data, Black Mesa Area, Northeastern Arizona - 2007-2008

    USGS Publications Warehouse

    Macy, Jamie P.

    2009-01-01

    The N aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area, which is typically about 6 to 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2007 to September 2008. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2007, total groundwater withdrawals were 4,270 acre-feet, industrial withdrawals were 1,170 acre-ft, and municipal withdrawals were 3,100 acre-ft. Total withdrawals during 2007 were about 41 percent less than total withdrawals in 2005. From 2006 to 2007, however, total withdrawals increased by 4 percent, industrial withdrawals decreased by approximately 2 percent, and total municipal withdrawals increased by 7 percent. From 2007 to 2008, annually measured water levels in the Black Mesa area declined in 6 of 11 wells measured in the unconfined areas of the N aquifer, and the median change was -0.2 feet. Water levels declined in 9 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.2 feet. From the prestress period (prior to 1965) to 2008, the median water-level change for 33 wells in both the confined and unconfined area was -12.9 feet. Median water-level changes were -1.0 feet for 15 wells measured in the unconfined areas and -33.2 feet for 18 wells measured in the confined area. Spring flow was measured at two springs in 2008. Flow decreased at both Moenkopi School Spring and Pasture Canyon Spring from previous years. Flow fluctuated during the period of record, but a decreasing trend was apparent. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2007), Dinnebito Wash near Sand Springs 09401110 (1993 to 2007), Polacca Wash near Second Mesa 09400568 (1994 to 2007), and Pasture Canyon Springs 09401265 (August 2004 to 2007). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater. The period of record is too short to determine if there is a trend at Pasture Canyon Spring. In 2008, water samples collected from 6 wells and 2 springs in the Black Mesa area were analyzed for selected chemical constituents and the results compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 6 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no trend in those data.

  9. Paleomagnetism on the Quaternary marine sediment at the DH-1 long-core site in the Korean continental margin of the East Sea

    NASA Astrophysics Data System (ADS)

    Ryang, Woo Hun; Lee, Byungju

    2014-05-01

    A long core of 23.6 m was acquired in the Korean continental margin of the western East Sea. The core site of the DH-1 is located in the offshore of the Donghae City and the water depth is 357.8 m deep. In this area, the paleomagnetism and magnetostratigraphy were firstly reported using 420 samples collected from the long-core sediments. Based on the inclination distribution of the depositional remanent magnetization, the DH-1 core could be divided into two upper and lower units at the boundary of 1750 cm below seafloor. The upper unit is characterized by a positive polarity, whereas the lower unit by a negative polarity. The boundary of the upper and lower units was interpreted as the Brunhes-Matuyama boundary (778 ka). The chemical components of tephra layer at 2014 cm below seafloor belong to alkaline series, plotted between the tephra components of the Mount Baekdu and Ulleung Island. Key words: magnetostratigraphy, Brunhes-Matuyama boundary, tephra, East Sea Acknowledgements: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0025733) and by the Ministry of Knowledge Economy through the grant of Marine Geology and Geophysical Mapping Project (GP2010-013).

  10. Fiscal year 1996 decontamination and decommissioning activities photobriefing book for the Argonne National Laboratory-East Site, Technology Development Division, Waste Management Program, Decontamination and Decommissioning Projects Department

    SciTech Connect

    1996-12-31

    The Photobriefing Book describes the Decontamination and Decommissioning (D and D) Program at the Argonne National Laboratory-East Site (ANL-E) near Lemont, Illinois. This book summarizes current D and D projects, reviews fiscal year (FY) 1996 accomplishments, and outlines FY 1997 goals. A section on D and D Technology Development provides insight on new technologies for D and D developed or demonstrated at ANL-E. Past projects are recapped and upcoming projects are described as Argonne works to accomplish its commitment to, ``Close the Circle on the Splitting of the Atom.`` Finally, a comprehensive review of the status and goals of the D and D Program is provided to give a snap-shot view of the program and the direction it`s taking as it moves into FY 1997. The D and D projects completed to date include: Plutonium Fuel Fabrication Facility; East Area Surplus Facilities; Experimental Boiling Water Reactor; M-Wing Hot Cell Facilities; Plutonium Gloveboxes; and Fast Neutron Generator.

  11. Using Bayesian optimization method and FLEXPART dispersion model to evaluate CO emission in East China based on three-year measurements at high altitude mountain site

    NASA Astrophysics Data System (ADS)

    Xiaole, P.; Kanaya, Y.; Wang, Z.

    2012-12-01

    The rapid economic growth and energy consumption in East China has resulted in serious regional-scale and trans-boundary air pollutions. Variation of carbon monoxide (CO) is of great interest as a restriction factor for pollutants related with incomplete combustion processes. This study attempted to evaluate CO emission in East China using analytical inverse modeling and nearly three-year measurements (2005-2007) at Mt. Huashan (34°28'52"N, 110°04'36"E, a.s.l.1577 m). Inversion methodology combined FLEXPART_WRF (Version 6.2) with Bayesian optimization iterative algorithm. Regarding calculations, five days backward simulations of air mass movement were used to determine the Source-Receptor Relationship (SRR) between emissions at the source regions and observation at receptor. And then SRR, a priori CO emission (INTEX-B) and corresponding uncertainties (70%) were fed into inversion algorithm to optimize the CO emission by minimizing the mismatch between simulated and observed CO concentrations. To reduce the number of unknowns (a posterior), we used variable-resolution grid setting with high spatial resolution in the vicinity of observation site and coarse resolution for the regions some distance away due to decrease of SRR values. Inversion result showed that simulation of CO mixing ratio with the a posterior information was evidently improved, reducing root-mean square (RMS) of differences between observation and simulation by 30%. A posterior indicated that CO emission in East China was probably 10%, 25% and 6% of underestimated by emission inventory for spring, autumn and winter time. Spatial distribution of a posterior indicated that North China Plain (30°N-40°N, 110°E-120°E) significantly accounted for the total increase of CO emission in the East China; Nevertheless, the CO emission from South China region (20°N-30°N, 100°E-120°E) might be overestimated ~10% annually. Uncertainties analysis with repeated random samplings approach demonstrated that inversion result was relatively sensitive to the emission from the regions where city and industries were concentrated, highlighting the great variability of CO emission from anthropogenic sources.

  12. A Hydrostratigraphic Model of the Pahute Mesa - Oasis Valley Area, Nye County, Nevada

    SciTech Connect

    S. L. Drellack, Jr.; L. B. Prothro; J. L. Gonzales

    2001-12-01

    A 3-D hydrostratigraphic framework model has been built for the use of hydrologic modelers who are tasked with developing a model to determine how contaminants are transported by groundwater flow in an area of complex geology. The area of interest includes Pahute Mesa, a former nuclear testing area at the Nevada Test Site (NTS), and Oasis Valley, a groundwater discharge area down-gradient from contaminant source areas on Pahute Mesa. To build the framework model, the NTS hydrogeologic framework was integrated with an extensive collection of drill-hole data (stratigraphic, lithologic, and alteration data); a structural model; and several recent geophysical, geological, and hydrological studies to formulate a hydrostratigraphic system. The authors organized the Tertiary volcanic units in the study area into 40 hydrostratigraphic units that include 16 aquifers, 13 confining units, and 11 composite units. The underlying pre-Tertiary rocks were divided into six hydrostratigraphic units, including two aquifers and four confining units. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units (''layers'' in the model) along with all the major structural features that control them, including calderas and faults. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to address alternative interpretations for some of the major features in the model. Six of these alternatives were developed so they could be modeled in the same fashion as the base model.

  13. Magnetochronology of the Feiliang Paleolithic site in the Nihewan Basin and implications for early human adaptability to high northern latitudes in East Asia

    NASA Astrophysics Data System (ADS)

    Deng, Chenglong; Xie, Fei; Liu, Caicai; Ao, Hong; Pan, Yongxin; Zhu, Rixiang

    2007-07-01

    We present a new magnetostratigraphic dating of the Feiliang Paleolithic site in the Nihewan Basin, northern China. Partially-oxidized magnetite and hematite were identified as the main carriers for the characteristic remanent magnetizations of the fluvio-lacustrine sediments. Paleomagnetic results suggest that the sequence recorded the very early Brunhes chron and the upper Matuyama chron, including the Jaramillo subchron. The Feiliang artifact layer was determined to be within the pre-Jaramillo Matuyama chron, with an estimated age of ca. 1.2 Ma. Our finding, coupled with previously published magnetochronology, strongly indicates a prominent early human flourishing in the high northern latitudes of East Asia during or just prior to the Mid-Pleistocene climate transition.

  14. Environmental assessment for the new looped power system on Rainier Mesa

    SciTech Connect

    Not Available

    1992-08-26

    The Nevada Test Site (NTS) is the single location within the continental United States where tests involving nuclear explosive devices are conducted. The NTS is a land mass of 1,350 square miles. It is located 65 miles northwest of Las Vegas, Nevada, on the eastern edge of the Great Mohave Desert in high desert country where altitude ranges from 3,500 feet to approximately 7,700 feet. It is in a remote, isolated and sparsely populated area. The proposed action supports the underground nuclear weapons test program conducted on the NTS as defined in the Nevada Test Site Final Environmental Impact Statement, dated September 1977. The project involves the construction of a new looped power system, to be performed in three phases, indicated on Rainier Mesa in Area 12 at the NTS. The phases are described in this paper.

  15. Environmental status of algal mat sites located at the east coast of Saudi Arabia following the Gulf War

    SciTech Connect

    Al-Thukair, A. )

    1993-06-01

    Remote sensing techniques and ground truth verification were used to provide information on algal mat locations and damage intensity caused by the oil spill. Pre and post oil spill satellite images, ground truth assessment were compared for damage evaluation. Locations and sites status (heavily oiled, recovering, and no algal mats) were conveyed in maps. Recovered sites are found in Abu Ali and Tanajib areas. However, recovery seems to be slower in Abu Ali area as compared to Tanajib. Different types and formations of algal mats were found in both areas. This differentiation is more likely to be attributable to coastal topography and tide regimes.

  16. Feasibility Study of Economics and Performance of Solar Photovoltaics at the TechCity East Campus Resource Conservation and Recovery Act Site in Kingston, New York. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    SciTech Connect

    Salasovich, J.; Geiger, J. W.; Mosey, G.; Healey, V.

    2014-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the TechCity East Campus site in Kingston, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this study is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  17. Selection of astrophysical/astronomical/solar sites at the Argentina East Andes range taking into account atmospheric components

    NASA Astrophysics Data System (ADS)

    Piacentini, R. D.; García, B.; Micheletti, M. I.; Salum, G.; Freire, M.; Maya, J.; Mancilla, A.; Crinó, E.; Mandat, D.; Pech, M.; Bulik, T.

    2016-06-01

    In the present work we analyze sites in the Argentinian high Andes mountains as possible places for astrophysical/astronomical/solar observatories. They are located at: San Antonio de los Cobres (SAC) and El Leoncito/CASLEO region: sites 1 and 2. We consider the following atmospheric components that affect, in different and specific wavelength ranges, the detection of photons of astronomical/astrophysical/solar origin: ozone, microscopic particles, precipitable water and clouds. We also determined the atmospheric radiative transmittance in a day near the summer solstice at noon, in order to confirm the clearness of the sky in the proposed sites at SAC and El Leoncito. Consequently, all the collected and analyzed data in the present work, indicate that the proposed sites are very promising to host astrophysical/astronomical/solar observatories. Some atmospheric components, like aerosols, play a significant role in the attenuation of light (Cherencov and/or fluorescence) detected in cosmic rays (particles or gamma photons) astrophysical observatories, while others, like ozone have to be considered in astronomical/solar light detection.

  18. Characterisation of PM 10 atmospheric aerosols for the wet season 2005 at two sites in East Africa

    NASA Astrophysics Data System (ADS)

    Mkoma, Stelyus L.; Maenhaut, Willy; Chi, Xuguang; Wang, Wan; Raes, Nico

    Ambient daily PM 10 aerosol samples were collected at two sites in Tanzania in May and June 2005 (during the wet season), and their chemical characteristics were studied. The sites were a rural site in Morogoro and an urban kerbside site in Dar es Salaam. A Gent PM 10 stacked filter unit sampler with sequential Nuclepore polycarbonate filters, providing fine and coarse size fractions, and a PM 10 sampler with quartz fibre filters were deployed. Parallel collections of 24 h were made with the two samplers and the number of these collections was 13 in Morogoro and 16 in Dar es Salaam. The average mass concentration of PM 10 was 27 ± 11 μg/m 3 in Morogoro and 51 ± 21 μg/m 3 in Dar es Salaam. In Morogoro, the mean concentrations of organic carbon (OC), elemental carbon (EC), and water-soluble organic carbon (WSOC) were 6.8, 0.51, and 2.8 μg/m 3, respectively. In contrast, higher mean concentrations (11.9, 4.6, and 3.3 μg/m 3, respectively) were obtained for Dar es Salaam. At both sites, species and elements, such as black carbon, NH 4+, non-sea-salt SO 42-, K, and Ni (and at Dar es Salaam also V, As, Br, and Pb) were mainly present in the fine size fraction. The common crustal and sea-salt elements, including Na, Mg, Al, Si, Cl, Ca, Ti, Mn, Fe, and Sr, and also NO 3- and P (and to a lesser extent Cu and Zn) were concentrated in the coarse particles. Aerosol chemical mass closure indicated that the PM 10 mass in Morogoro consisted, on average, of 48% organic matter (OM), 44% crustal matter, 4% sea salt, and 2% EC, while in Dar es Salaam OM, crustal matter, sea salt, and EC represented 37%, 32%, 9%, and 9% of the PM 10 mass. The contributions of the secondary inorganic aerosol (non-sea-salt sulphate, nitrate, and ammonium) were small, i.e., only 5% in total at each site. Carbonaceous materials and crustal matter were thus the most important components of the PM 10 mass. It is suggested that biomass burning is a major contributor to the OM; at Dar es Salaam there is also a very substantial contribution from traffic. A source apportionment calculation indicated that 68% of the OC at this site originated from traffic exhaust versus 32% from charcoal burning. The crustal matter at Morogoro is likely mainly attributable to soil dust resuspension, whereas in Dar es Salaam it is likely mostly resuspended road dust.

  19. Comparison of mosquito control programs in seven urban sites in Africa, the Middle East, and the Americas

    PubMed Central

    Impoinvil, Daniel E.; Ahmad, Sajjad; Troyo, Adriana; Keating, Joseph; Githeko, Andrew K.; Mbogo, Charles M; Kibe, Lydiah; Githure, John I.; Gad, Adel M.; Hassan, Ali N.; Orshan, Laor; Warburg, Alon; Calderón-Arguedas, Olger; Sánchez-Loría, Victoria M.; Velit-Suarez, Rosanna; Chadee, Dave D.; Novak, Robert J.; Beier, John C.

    2007-01-01

    Mosquito control programs at seven urban sites in Kenya, Egypt, Israel, Costa Rica, and Trinidad are described and compared. Site-specific urban and disease characteristics, organizational diagrams, and strengths, weaknesses, obstacles and threats (SWOT) analysis tools are used to provide a descriptive assessment of each mosquito control program, and provide a comparison of the factors affecting mosquito abatement. The information for SWOT analysis is collected from surveys, focus group discussions, and personal communication. SWOT analysis identified various issues affecting the efficiency and sustainability of mosquito control operations. The main outcome of our work was the description and comparison of mosquito control operations within the context of each study site’s biological, social, political, management, and economic conditions. The issues identified in this study ranged from lack of inter-sector collaboration to operational issues of mosquito control efforts. A lack of sustainable funding for mosquito control was a common problem for most sites. Many unique problems were also identified, which included lack of mosquito surveillance, lack of law enforcement, and negative consequences of human behavior. Identifying common virtues and shortcomings of mosquito control operations is useful in identifying “best practices” for mosquito control operations, thus leading to better control of mosquito biting and mosquito-borne disease transmission. PMID:17316882

  20. Assessing the water quality response to an alternative sewage disposal strategy at bathing sites on the east coast of Ireland.

    PubMed

    Bedri, Zeinab; O'Sullivan, John J; Deering, Louise A; Demeter, Katalin; Masterson, Bartholomew; Meijer, Wim G; O'Hare, Gregory

    2015-02-15

    A three-dimensional model is used to assess the bathing water quality of Bray and Killiney bathing sites in Ireland following changes to the sewage management system. The model, firstly calibrated to hydrodynamic and water quality data from the period prior to the upgrade of the Wastewater Treatment Works (WwTW), was then used to simulate Escherichia coli (E. coli) distributions for discharge scenarios of the periods prior to and following the upgrade of the WwTW under dry and wet weather conditions. E. coli distributions under dry weather conditions demonstrate that the upgrade in the WwTW has remarkably improved the bathing water quality to a Blue Flag status. The new discharge strategy is expected to drastically reduce the rainfall-related incidents in which environmental limits of the Bathing Water Directive are breached. However, exceedances to these limits may still occur under wet weather conditions at Bray bathing site due to storm overflows that may still be discharged through two sea outfalls offshore of Bray bathing site. PMID:25577474

  1. Prediction and characterization of novel epitopes of serotype A foot-and-mouth disease viruses circulating in East Africa using site-directed mutagenesis.

    PubMed

    Bari, Fufa Dawo; Parida, Satya; Asfor, Amin S; Haydon, Daniel T; Reeve, Richard; Paton, David J; Mahapatra, Mana

    2015-05-01

    Epitopes on the surface of the foot-and-mouth disease virus (FMDV) capsid have been identified by monoclonal antibody (mAb) escape mutant studies leading to the designation of four antigenic sites in serotype A FMDV. Previous work focused on viruses isolated mainly from Asia, Europe and Latin America. In this study we report on the prediction of epitopes in African serotype A FMDVs and testing of selected epitopes using reverse genetics. Twenty-four capsid amino acid residues were predicted to be of antigenic significance by analysing the capsid sequences (n = 56) using in silico methods, and six residues by correlating capsid sequence with serum-virus neutralization data. The predicted residues were distributed on the surface-exposed capsid regions, VP1-VP3. The significance of residue changes at eight of the predicted epitopes was tested by site-directed mutagenesis using a cDNA clone resulting in the generation of 12 mutant viruses involving seven sites. The effect of the amino acid substitutions on the antigenic nature of the virus was assessed by virus neutralization (VN) test. Mutations at four different positions, namely VP1-43, VP1-45, VP2-191 and VP3-132, led to significant reduction in VN titre (P value = 0.05, 0.05, 0.001 and 0.05, respectively). This is the first time, to our knowledge, that the antigenic regions encompassing amino acids VP1-43 to -45 (equivalent to antigenic site 3 in serotype O), VP2-191 and VP3-132 have been predicted as epitopes and evaluated serologically for serotype A FMDVs. This identifies novel capsid epitopes of recently circulating serotype A FMDVs in East Africa. PMID:25614587

  2. Differential sensitivity theory applied to the MESA code

    NASA Astrophysics Data System (ADS)

    Henninger, R. J.; Maudlin, P. J.; Harstad, E. N.

    1994-07-01

    A technique called Differential Sensitivity Theory (DST) is applied to the system of equations solved by the MESA continuum mechanics code. DST uses adjoint technique to determine exact sensitivity derivatives, i.e., if R is a calculation result of interest (response R ) and αi is a calculational input (parameter αi), then αR/αi is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem all n sensitivities can be obtained by integrating the solutions from only two calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics (ACM) code. This work presents the derivation and solution of the appropriate set of adjoint equations for the purpose of computing sensitivities for high-rate two-dimensional, multi-component, high-deformation problems. As an example, results for a flyer plate impact problem are given.

  3. Ambient resonance of Mesa Arch, Canyonlands National Park, Utah

    NASA Astrophysics Data System (ADS)

    Starr, Alison M.; Moore, Jeffrey R.; Thorne, Michael S.

    2015-08-01

    We analyzed the resonance characteristics of a prominent natural arch in Canyonlands National Park, Mesa Arch, as measured from ambient seismic data. Evaluating spectral and polarization attributes, we distinguished the first four resonant frequencies of the arch, 2.9, 6.0, 6.9, and 8.5 Hz, as well as basic properties of the associated mode shapes. We then affirmed experimental data using 3-D numerical modal analysis, providing estimates of material properties and clarifying vibrational mode shapes. Monitoring resonant frequencies over time, we searched for shifts associated with changing environmental conditions and long-term progressive damage. We measured ~3% direct daily variation in resonant frequency associated with changing rock temperature, thermal stress, and stiffening of the rock matrix. Independent tilt data showed similar diurnal cycles associated with thermoelastic stresses and deformation of the arch. We observed no permanent resonant frequency shifts related to irreversible damage of Mesa Arch during our study period.

  4. Temporal trajectories of wet deposition across hydro-climatic regimes: Role of urbanization and regulations at U.S. and East Asia sites

    NASA Astrophysics Data System (ADS)

    Park, Jeryang; Gall, Heather E.; Niyogi, Dev; Rao, P. Suresh C.

    2013-05-01

    Dominant global patterns of urbanization and industrialization contribute to large-scale modification of the drivers for hydrologic and biogeochemical processes, as evident in Asia, Africa, and South America which are experiencing rapid population and economic growth. One manifestation of urbanization and economic development is decreases in air quality, increases in dry/wet deposition fluxes, and growing adverse impacts on public health and ecosystem integrity. We examined available long-term (1980-2010) observational data, gathered at weekly intervals, for wet deposition at 19 urban sites in the U.S., and monitoring data (2000-2009) available for 17 urban sites at a monthly scale in East Asia. Our analyses are based on data for four constituents (SO42-, NO3-, Ca2+, and Mg2+); differences in atmospheric chemistry and terrestrial sources of these constituents enabled a robust comparative analysis. We examined intra-annual variability and the long-term temporal trajectories of wet deposition fluxes to discern the relative role of anthropogenic and stochastic hydro-climatic forcing. Here, we show that: (1) temporal variability in wet deposition fluxes follows an exponential probability density function at all sites, evidence that stochasticity of rainfall is the dominant control of wet deposition variability; (2) the mean wet deposition flux, μΩ (ML-2T-1), has decreased in the U.S. over time since enactment of the Clean Air Act, with μΩ having become homogenized across varying hydro-climatic regimes; and (3) in contrast, μΩ values for East Asian cities are 3-10 times higher than U.S. cities, attributed to lax regulatory enforcement. Based on the observed patterns, we suggest a stochastic model that generates ellipses within which the μΩ temporal trajectories are inscribed. In the U.S., anthropogenic forcing (regulations) is dominant in the humid regions, while variability in hydro-climatic forcing explains inter-annual variability in arid regions. Our stochastic analysis facilitates projections of the temporal trajectory shifts in wet deposition fluxes as a result of urbanization and other land-use changes, climate change, and regulatory enforcement.

  5. Bedrock topography and wind erosion sites in East Antarctica: observations from the 2002 US-ITASE traverse

    NASA Astrophysics Data System (ADS)

    Welch, Brian C.; Jacobel, Robert W.

    Ice stratigraphy from deep-penetrating radar data collected during the 2002 US International Trans-Antarctic Scientific Expedition (US-ITASE) traverse shows evidence of a significant erosion surface and drift-filled basin related to a previously undiscovered 1400 m subglacial mountain between Hercules Dome (87 42?S, 108 W) and South Pole. The 3 MHz radar profile crosses three subglacial mountains at approximately 45 to the ice-flow direction. Cross-cutting reflectors in the top 500 m of ice stratigraphy are interpreted as angular unconformities resulting from wind erosion as the ice deforms over the mountain tops. The unconformities correlate locally with zones of high RADARSAT reflectivity. Several nearby sites with similar relatively high RADARSAT reflectivity adjacent to the traverse indicate that active wind erosion may be taking place at these locations as well. Based on the local correlation between surface wind scour and subglacial topography, we interpret the nearby cluster of bright RADARSAT reflectivity to indicate the presence of a small range of subglacial mountains. The ability to trace isochronal stratigraphy, associated with scour sites using shallow and deep radar, to nearby dated ice cores presents the possibility of exploiting wind-scour zones to access well-dated older ice with shallow-coring equipment.

  6. Gravimetric response of water table fluctuations in the Sahelian Diffa site (East Niger): local effects including poro-elasticity

    NASA Astrophysics Data System (ADS)

    Hector, B.; Genthon, P.; Le Coz, M.; Hinderer, J.; Chalikakis, K.; Descloitres, M.

    2010-12-01

    The GHYRAF project (Gravimetry and HYdrology in AFrica) is devoted to a regional study of the relationship between hydrological and gravimetric signals in the Western African Monsoon area. Three sites are monitored in a decreasing pluviometric gradient: Djougou (North Benin), Wankama (Niamey area) and Bagara (Eastern Niger) with annual rainfalls amounting to 1200 mm, 600 mm and 350 mm, respectively. The Diffa/Bagara site is located 640m away from the Yobé temporary river, a tributary of Lake Chad fed by rainfall on the Jos Plateau (Nigeria) and that is generally flowing between mid July and January. Apart from this period, the river bed includes a series of ponds that form the top of the aquifer and that are pumped for intensive irrigated cropping. The 50m thick uppermost unconfined aquifer is locally recharged by the Yobé River and is flowing northwards. It has been explored by geophysical methods involving RMS and TDEM soundings, which provided information on its porosity and electrical conductivity, respectively. A series of nearly 50 holes drilled down to a 10 m depth in the Bagara area allowed to define the detailed sedimentary structure of the aquifer. It consists mainly of fluvial deposits with alternating layers of fine sands, coarse grained sands and clays. The sedimentary pile includes clayed layer of centimetric to metric thickness with a mean lateral extension of 300 m. The groundwater level is monitored by a series of 4 piezometers located at 25 m, 270 m, 500 m and 640 m from the river axis. The shape of the piezometric curve at the Bagara station is 0.4 m amplitude sinusoid and presents a maximum level at mid January and a minimum one near mid July. Clearly, water level fluctuations are governed by infiltration from the Yobe river with an offset controlled by the distance to it. With the 20% porosity measured by MRS, this would imply a nearly 30 nms-2 gravimetric signal, which is in fair agreement with the observed amplitude. However both the observed gravimetic signal and the results of the global hydrological model GLDAS are offset with respect to the piezometric one. In order to assess the influence of local effects, the groundwater level is modeled with the USGS finite-difference ModFlow code using different properties sets of the aquifer deduced from statistical analysis of drill-holes data. Poroelasticity effects resulting from variable saturation of the clay layers observed near the water level on the Bagara site are assessed. The ability of gravity data for monitoring annual and long term water level changes in the uppermost aquifer is then discussed.

  7. Deep Sea Drilling Project Site 612 bolide event: new evidence of a late Eocene impact-wave deposit and a possible impact site, US east coast

    USGS Publications Warehouse

    Poag, C.W.

    1992-01-01

    A remarkable >60-m-thick, upward-fining, polymictic, marine boulder bed is distributed over >15 000 km2 beneath Chesapeake Bay and the surrounding Middle Atlantic Coastal Plain and inner continental shelf. The wide varieties of clast lithologies and microfossil assemblages were derived from at least seven known Cretaceous, Paleocene, and Eocene stratigraphic units. The supporting pebbly matrix contains variably mixed assemblages of microfossils along with trace quantities of impact ejecta. The youngest microfossils in the boulder bed are of early-late Eocene age. On the basis of its unusual characteristics and its stratigraphic equivalent to a layer of impact ejecta at Deep Sea Drilling Project (DSDP) Site 612. It is postulated that this boulder bed was formed by a powerful bolide-generated wave train that scoured the ancient inner shelf and coastal plain of southeastern Virginia. -from Authors

  8. Coal slurry pipelines: Blach Mesa and future projects

    SciTech Connect

    Brolick, H.J.

    1998-12-31

    Most people in the mining industry have some familiarity with pipelining of minerals in slurry form, however, many may not realize the extent that mineral slurry pipeline transport is used throughout the world. The author is referring to the shipment of the minerals in the raw or concentrate form, not tailings pipelines which are also commonplace in the minerals industry. There are over forty mineral pipelines around the world. The list covers a wide range of minerals, including copper ore concentrate, iron ore concentrate, limestone, phosphate concentrate, kaolin, Gilsonite and gold ore, with only eleven of the mineral pipelines located in the USA. It should be noted that one of the earliest slurry pipelines was a 108 mile coal slurry pipeline in Ohio, which started up in 1957. The pipeline only operated until 1963 when a railroad company literally bought out the transportation contract. This really was the beginning of the unit train concept. Each mineral has specific physical and chemical characteristics to be considered when evaluating transport by pipeline. The processing required at the pipeline origin, as well as at the pipeline termination, are also important factors in determining slurry pipeline feasibility. Transport distance, annual volume, and continuity of shipments are other important factors. One of the most difficult minerals to transport as a slurry is coal because the specific gravity is closer to water than most other minerals. Thus, the fine balance of creating enough fine particles to serve as a carrier for the coarser material, while at the same time having a material that can be economically dewatered is very sensitive and technical designs will vary with types of coal. Additionally, since coal is purchased for its thermal value, excess surface moisture can lower the value of the coal to the customer. One of the most successful slurry pipeline operations, and the only current operating long-distance coal slurry pipeline is the Black Mesa Pipeline System. The Black Mesa Pipeline is a 273 mile (439 km) long, 18-inch (457 mm) coal/water slurry pipeline, originating on the Black Mesa in the Northeastern part of Arizona, USA. The system delivers coal from the Peabody Coal Company`s Black Mesa open pit mine to the Mohave Generating Station which is a 1580 MW steam powered electric generating plant located in Laughlin, Nevada. Black Mesa Pipeline began commercial operation in November, 1970 and has transported in excess of 110,000,000 tons (99,800,000 metric tons) of coal with an availability factor of 99%.

  9. A comparison of food habits and prey preference of Amur tiger (Panthera tigris altaica) at three sites in the Russian Far East.

    PubMed

    Kerley, Linda L; Mukhacheva, Anna S; Matyukhina, Dina S; Salmanova, Elena; Salkina, Galina P; Miquelle, Dale G

    2015-07-01

    Prey availability is one of the principal drivers of tiger distribution and abundance. Therefore, formulating effective conservation strategies requires a clear understanding of tiger diet. We used scat analysis in combination with data on the abundance of several prey species to estimate Amur tiger diet and preference at 3 sites in the Russian Far East. We also examined the effect of pseudoreplication on estimates of tiger diet. We collected 770 scats across the 3 sites. Similar to previous studies, we found that tigers primarily preyed on medium to large ungulates, with wild boar, roe, sika and red deer collectively comprising 86.7% of total biomass consumed on average. According to Jacobs' index, tigers preferred wild boar, and avoided sika deer. Variation in preference indices derived from these scat analyses compared to indices derived from kill data appear to be due to adjustments in biomass intake when sex-age of a killed individual is known: a component missing from scat data. Pseudoreplication (multiple samples collected from a single kill site) also skewed results derived from scat analyses. Scat analysis still appears useful in providing insight into the diets of carnivores when the full spectrum of prey species needs to be identified, or when sample sizes from kill data are not sufficient. When sample sizes of kill data are large (as is now possible with GPS-collared animals), kill data adjusted by sex-age categories probably provides the most accurate estimates of prey biomass composition. Our results provide further confirmation of the centrality of medium ungulates, in particular wild boar, to Amur tiger diet, and suggest that the protection of this group of species is critical to Amur tiger conservation. PMID:25939758

  10. Nutrient export in run-off from an in-field cattle overwintering site in East-Central Saskatchewan.

    PubMed

    Smith, A; Schoenau, J; Lardner, H A; Elliott, J

    2011-01-01

    Wintering cattle directly in the field creates potential concerns with water quality, as nutrients added from urine and fecal material over the winter can end up in runoff water, ground water and soil. In 2008/2009 an experiment was conducted to observe the effect of in-field winter feeding of cows on the nutrients in spring snowmelt run-off water. Low temperatures give little opportunity for organic N, urea and ammonium added in the urine and fecal matter to convert to nitrate, resulting in nitrate-N concentrations in snowmelt run-off water that were similar in the control and winter fed areas. Orthophosphate-P and ammonium-N concentrations were significantly elevated in run-off from the winter feed treatment basins compared to the controls. Surface soil sampled in the spring from the winter feeding site had higher soluble nitrate while soluble forms of phosphorus in the soil were lower compared to the fall soil samples. Caution should be used when utilizing in-field winter feeding systems so that the runoff water does not reach sensitive water bodies. PMID:22020470

  11. Record of the early Holocene deglaciation from the East Antarctic Adélie Land margin: IODP Site U1357

    NASA Astrophysics Data System (ADS)

    Escutia, Carlota; Jimenez-Espejo, Francisco; Salabarnada, Ariadna; Gitiérrez-Pastor, Julia

    2015-04-01

    Drilling at Site U1357 yielded a 185.6 m section of Holocene continuously laminated diatom ooze as well as a portion of an underlying Last Glacial Maximum diamict. We present sedimentological and geochemical data of the time of the first Holocene deglaciation. The use of CT-Scanner has allowed us to characterize in detail sedimentary facies dominated by iceberg rafted debris, silt layers and biogenic laminations. In addition, geochemical studies have been conducted at ultra-high (seasonal to decadal) resolution using X-Ray Fluorescence scanning, allowing to reconstruct detrital input, paleoproducitivity and redox conditions. Comparison between CT-Scan images and geochemical data show that the intervals with high Ba/Al and Si/Al are associated to poor detrital levels allowing to use these ratios along the entire core as detrital/paleoproductivity proxies. Detrital proxies (e.g., Zr content) anticorrelate with bottom redox conditions proxies (U/Th) pointing to well oxygenated deep waters as generator for silt layers. These preliminary observations point to an unprecedented high resolution ice fjord-like sequence in the studied region with strong water column stratification and pulsational detrital input acting as a main forcing for environmental variations. Ongoing radiocarbon analysis, performed in the bulk fraction and also in compound-specific, will allow us to recognize timing, cylces and if major variations occurred in the reservoir age during the deglaciation.

  12. Completion Report for Well ER-12-3 Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain

    SciTech Connect

    U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office; Bechtel Nevada Corporation

    2006-05-01

    Well ER-12-3 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. The well was drilled in March and April 2005 as part of a hydrogeologic investigation program for the Rainier Mesa-Shoshone Mountain Corrective Action Unit. The overall purpose of the well was to gather subsurface data to better characterize the hydrogeology of central Rainier Mesa, especially in the older Tertiary volcanic rocks and Paleozoic sedimentary rocks. The main 47.0-centimeter hole was drilled to a depth of 799.2 meters and cased with 33.97-centimeter casing to 743.1 meters. The hole diameter was then decreased to 31.1 centimeters, and the well was drilled to a total depth of 1,496.0 meters. The completion string consisted of 13.97-centimeter stainless steel casing, with two slotted intervals open to the lower carbonate aquifer, suspended from 19.37-centimeter carbon steel casing. A piezometer string was installed outside the 33.97-centimeter casing to a depth of 467.1 meters to monitor a zone of perched water within the Tertiary volcanic section. Data gathered during and shortly after hole construction include composite drill cuttings samples collected every 3 meters (extra cuttings samples were collected from the Paleozoic rocks for paleontological analyses), sidewall core samples from 35 depths, various geophysical logs, and water level measurements. These data indicate that the well penetrated 674.2 meters of Tertiary volcanic rocks and 821.7 meters of Paleozoic dolomite and limestone. Forty-nine days after the well was completed, but prior to well development and testing, the water level inside the main hole was tagged at the depth of 949.1 meters, and the water level inside the piezometer string was tagged at 379.9 meters.

  13. 37. PRATER CANYON AND CIVILIAN CONSERVATION CORPS CAMP SITE FROM ...

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

    37. PRATER CANYON AND CIVILIAN CONSERVATION CORPS CAMP SITE FROM PRATER GRADE, FACING E. SAME CAMERA LOCATION AS No. 35 AND No. 36. - Mesa Verde National Park Main Entrance Road, Cortez, Montezuma County, CO

  14. Availability, Sustainability, and Suitability of Ground Water, Rogers Mesa, Delta County, Colorado - Types of Analyses and Data for Use in Subdivision Water-Supply Reports

    USGS Publications Warehouse

    Watts, Kenneth R.

    2008-01-01

    The population of Delta County, Colorado, like that in much of the Western United States, is forecast to increase substantially in the next few decades. A substantial portion of the increased population likely will reside in rural subdivisions and use residential wells for domestic water supplies. In Colorado, a subdivision developer is required to submit a water-supply plan through the county for approval by the Colorado Division of Water Resources. If the water supply is to be provided by wells, the water-supply plan must include a water-supply report. The water-supply report demonstrates the availability, sustainability, and suitability of the water supply for the proposed subdivision. During 2006, the U.S. Geological Survey, in cooperation with Delta County, Colorado, began a study to develop criteria that the Delta County Land Use Department can use to evaluate water-supply reports for proposed subdivisions. A table was prepared that lists the types of analyses and data that may be needed in a water-supply report for a water-supply plan that proposes the use of ground water. A preliminary analysis of the availability, sustainability, and suitability of the ground-water resources of Rogers Mesa, Delta County, Colorado, was prepared for a hypothetical subdivision to demonstrate hydrologic analyses and data that may be needed for water-supply reports for proposed subdivisions. Rogers Mesa is a 12-square-mile upland mesa located along the north side of the North Fork Gunnison River about 15 miles east of Delta, Colorado. The principal land use on Rogers Mesa is irrigated agriculture, with about 5,651 acres of irrigated cropland, grass pasture, and orchards. The principal source of irrigation water is surface water diverted from the North Fork Gunnison River and Leroux Creek. The estimated area of platted subdivisions on or partially on Rogers Mesa in 2007 was about 4,792 acres of which about 2,756 acres was irrigated land in 2000. The principal aquifer on Rogers Mesa consists of alluvial-fan deposits that overlie shale and, locally, sandstone. Maps of the base of the aquifer, the water table, and the saturated thickness of the aquifer were prepared from data from the well files of the Colorado Division of Water Resources. The base of the aquifer generally is topographically higher than the valleys of the North Fork Gunnison River and Leroux Creek, and direct hydraulic connection of the aquifer to North Fork Gunnison River and Leroux Creek is limited. The aquifer is recharged primarily by infiltration of surface water diverted for irrigation. Ground water discharges to seeps and springs and through slope deposits at the boundaries of the aquifer. Data from the well files also were used to estimate the specific capacity of wells and to estimate the transmissivity and hydraulic conductivity of the aquifer. A water budget was used to estimate recharge to and discharge from the aquifer. Although storage within the aquifer likely varies seasonally and from year to year, it was assumed that there were no long-term changes in ground-water storage. Estimated average annual recharge to and discharge from the aquifer during November 1998 through October 2006 were about 30,767 acre-feet per year. Although sufficient ground water is available on Rogers Mesa for additional domestic water supplies, conversion of irrigated land to residential land use likely would reduce recharge to the aquifer, affecting the sustainability of ground-water supplies on Rogers Mesa. Stream-depletion analyses indicate that the ground water in the aquifer likely would be considered tributary ground water and additional uses of ground water to supply new subdivisions likely would require implementation of augmentation plans. Although sufficient ground water is available on Rogers Mesa for additional domestic water supplies, conversion of irrigated land to residential land use likely would reduce recharge to the aquifer, affecting the sustainability

  15. 40Ar 39Ar age constraints on neogene sedimentary beds, Upper Ramparts, half-way Pillar and Canyon village sites, Porcupine river, east-central Alaska

    USGS Publications Warehouse

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

    1994-01-01

    40Ar 39Ar ages of volcanic rocks are used to provide numerical constraints on the age of middle and upper Miocene sedimentary strata collected along the Porcupine River. Intercalated sedimentary rocks north of latitude 67??10???N in the Porcupine terrane of east-central Alaska contain a rich record of plant fossils. The fossils are valuable indicators of this interior region's paleoclimate during the time of their deposition. Integration of the 40Ar 39Ar results with paleomagnetic and sedimentological data allows for refinements in estimating the timing of deposition and duration of selected sedimentary intervals. 40Ar 39Ar plateau age spectra, from whole rock basalt samples, collected along the Upper Ramparts and near Half-way Pillar on the Porcupine River, range from 15.7 ?? 0.1 Ma at site 90-6 to 14.4 ?? 0.1 Ma at site 90-2. With exception of the youngest basalt flow at site 90-2, all of the samples are of reversed magnetic polarity, and all 40Ar 39Ar age spectrum results are consistent with the deposition of the entire stratigraphic section during a single interval of reversed magnetic polarity. The youngest flow at site 90-2 was emplaced during an interval of normal polarity. With age, paleomagnetic and sedimentological data, the ages of the Middle Miocene sedimentary rocks between the basalt flows at sites 90-1 and 90-2 can be assigned to an interval within the limits of analytical precision of 15.2 ?? 0.1 Ma; thus, the sediments were deposited during the peak of the Middle Miocene thermal maximum. Sediments in the upper parts of sites 90-1 and 90-2 were probably deposited during cooling from the Middle Miocene thermal maximum. 40Ar 39Ar results of plagioclase and biotite from a single tephra, collected at sites 90-7 and 90-8 along the Canyon Village section of the Porcupine River, indicate an age of 6.57 ?? 0.02 Ma for its time of eruption and deposition. These results, together with sedimentological and paleomagnetic data, suggest that all of the Upper Miocene lacustrine sedimentary rocks at these sites were deposited during a single interval of reversed magnetic polarity and may represent a duration of only about 40,000 years. The age of this tephra corresponds with a late late Miocene warm climatic interval. The results from the Upper Ramparts and Half-way Pillar sites are used to estimate a minimum interval of continental flood basalt activity of 1.1-1.5 million years, and to set limits for the timing and duration of Tertiary extensional tectonic activity in the Porcupine terrane. Our data indicate that the oroclinal flexure that formed before the deposition of the basalts at the eastern end of the Brooks Range was created prior to 15.7 ?? 0.1 Ma. ?? 1994.

  16. Light absorption and morphological properties of soot-containing aerosols observed at an East Asian outflow site, Noto Peninsula, Japan

    NASA Astrophysics Data System (ADS)

    Ueda, S.; Nakayama, T.; Taketani, F.; Adachi, K.; Matsuki, A.; Iwamoto, Y.; Sadanaga, Y.; Matsumi, Y.

    2015-09-01

    The coating of black carbon (BC) with inorganic salts and organic compounds can enhance the magnitude of light absorption by BC. To elucidate the enhancement of light absorption of aged BC particles and its relation to the mixing state and morphology of individual particles, we conducted observations of particles at an Asian outflow site in Noto Peninsula, Japan, in the spring of 2013. Absorption and scattering coefficients at 405, 532, and 781 nm and mass concentrations/mixing states of refractory-BC in PM2.5 were measured using a three-wavelength photoacoustic soot spectrometer and a single-particle soot photometer (SP2), respectively, after passage through a heater maintained at 300 or 400 °C or a bypass line maintained at room temperature (25 °C). The average enhancement of BC light absorption due to coating was estimated by comparing absorption coefficients at 781 nm for particles that with and without passing through the heater and was found to be 22-23 %. The largest enhancements (> 30 %) were observed under high absorption coefficient conditions when the air mass was long-range transported from urban areas in China. Aerosol samples were also analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer. The morphological features and mixing states of soot-containing particles of four samples collected during the high absorption coefficient events were analyzed by comparing microphotographs before and after the evaporation of beam-sensitive materials by irradiation with a high density electron beam. The majority of the soot in all samples was found as mixed particles with spherical sulfate or as clusters of sulfate spherules. For samples showing high enhancement (> 30 %) of BC light absorption, TEM showed that the internally mixed soot-containing particles tended to have a more spherical shape and to be embedded into the sulfate. The SP2 measurements also suggested that the proportion of thickly-coated soot was greater. Thus, the observed enhancement of BC light absorption was found to differ according to the mixing states and morphology of soot-containing particles. The enhancement of BC light absorption in our in situ measurements and its relation with individual features of soot-containing particles will be useful to evaluate direct radiative forcing in the leeward areas of large emission sources of BC.

  17. Light absorption and morphological properties of soot-containing aerosols observed at an East Asian outflow site, Noto Peninsula, Japan

    NASA Astrophysics Data System (ADS)

    Ueda, Sayako; Nakayama, Tomoki; Taketani, Fumikazu; Adachi, Kouji; Matsuki, Atsushi; Iwamoto, Yoko; Sadanaga, Yasuhiro; Matsumi, Yutaka

    2016-03-01

    The coating of black carbon (BC) with inorganic salts and organic compounds can enhance the magnitude of light absorption by BC. To elucidate the enhancement of light absorption of aged BC particles and its relation to the mixing state and morphology of individual particles, we conducted observations of particles at an Asian outflow site in Noto Peninsula, Japan, in the spring of 2013. Absorption and scattering coefficients at 405, 532, and 781 nm and mass concentrations/mixing states of refractory BC in PM2.5 were measured using a three-wavelength photoacoustic soot spectrometer and a single-particle soot photometer (SP2), respectively, after passage through a thermodenuder (TD) maintained at 300 or 400 °C or a bypass line maintained at room temperature (25 °C). The average enhancement factor of BC light absorption due to coating was estimated by comparing absorption coefficients at 781 nm for particles that with and without passing through the TD at 300 °C and was found to be 1.22. The largest enhancements (> 1.30) were observed under high absorption coefficient periods when the air mass was long-range transported from urban areas in China. Aerosol samples were also analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer. The morphological features and mixing states of soot-containing particles of four samples collected during the high absorption events were analyzed by comparing microphotographs before and after the evaporation of beam-sensitive materials by irradiation with a high-density electron beam. The majority of the soot in all samples was found as mixed particles with sulfate-containing spherules or as clusters of such spherules. For samples showing high enhancement (> 1.30) of BC light absorption, the TEM showed that the internally mixed soot-containing particles tended to have a more spherical shape and to be thickly coated. The SP2 measurements also suggested that the proportion of thickly coated soot was greater. Thus, the observed enhancement of BC light absorption was found to differ according to the mixing states and morphology of soot-containing particles. The enhancement of BC light absorption in our in situ measurements and its relation with individual features of soot-containing particles will be useful to evaluate direct radiative forcing in the downwind areas of large emission sources of BC.

  18. Magnetic Fabric Investigations of the Sapinero Mesa and Fish Canyon Tuffs, Northern Part of the Southern Rocky Mountain Volcanic Field, Colorado

    NASA Astrophysics Data System (ADS)

    Harper, C.; Martin, M.; Geissman, J. W.

    2013-12-01

    Exposures of two laterally extensive ignimbrites in the northern part of the Southern Rocky Mountain Volcanic Field (SRMVF) allow examination of the emplacement mechanisms of these pyroclastic deposits as a function of deposition on irregular preexisting topography using magnetic fabric techniques. The Sapinero Mesa Tuff (28.19 × 0.03 Ma) was erupted from the San Juan/Uncompahgre Caldera Complex and the Fish Canyon tuff (ca. 28.02 × 0.16 Ma) was erupted from the La Garita caldera. These ignimbrites are major components of the SRMVF and were emplaced on highly irregular paleotopography. The Sapinero Mesa Tuff was emplaced directly on the late Eocene West Elk Breccia near and west of the Blue Mesa reservoir and directly on Precambrian crystalline rocks south of the Blue Mesa reservoir. The Fish Canyon Tuff was emplaced directly on Precambrian crystalline rocks south and southwest of Gunnison. Our study of these two ignimbrites is concentrated in the northern part of the SRMVF and examines how these deposits were emplaced on different topographic features. To date, a total of 16 sites in the Fish Canyon and Sapinero Mesa tuffs have been collected and analyzed for determination of magnetic fabrics through measurements of anisotropy of magnetic susceptibility (AMS). These samples are currently being analyzed for measurements of anisotropy of anhysteretic remanent magnetization (AARM). Initial analyses indicate transport directions that generally coincide with the inferred regional north-northwest transport direction. Additional sampling includes a greater spatial extent and a more focused method of collection with an emphasis on localities chosen with careful consideration of relationships to paleotopographic features present during emplacement of the ignimbrites. Specifically, we have selected linear features of varying scales with strikes that vary significantly from the regional, inferred transport directions. Our work provides a means to compare regional inferred azimuthal flow directions and source location to localized flow directions. The resulting discrepancies may suggest a transport-driven response to local Precambrian topography attending deposition.

  19. An investigation of sulfur concentrations in soils and pine needles in Mesa Verde National Park, Colorado

    SciTech Connect

    Gladney, E.S.; Ferenbaugh, R.W.; Jones, E.A.; Bell, M.G.; Morgan, J.D.; Nelson, L.A.; Lundstrom, C.; Bowker, R.G.

    1993-03-01

    Sulfur measurements in different age groups of pinon pine needles and adjacent soil samples from ten sampling sites at Mesa Verde National Park were determined using combustion elemental analysis and chromatographic techniques. The primary goal was to establish base-line levels for elemental sulfur in the Park. Sulfur levels in foliage and soils were evaluated using analysis of variance techniques. Foliage sulfur concentrations differed significantly among the 10 sampling sites and among trees within sites; however, needles of different ages did not differ significantly in sulfur content. Average soil concentrations were very low, 17% of the average needle concentrations. Soil sulfur concentrations also differed significantly among the 10 sampling sites and at different depths in the soil. No statistical differences were evident in soils sampled at the four compass points (N, S, E, W) around each tree. These differences imply that large numbers of samples are needed to identify small effects from anthropogenic inputs of sulfur into the system or that the effects must be large relative to the differences among sampling sites and individual trees in order to be detected.

  20. Preliminary stratigraphic and hydrostratigraphic correlation of four deep coreholes east of the Savannah River Site in Allendale, Barnwell, and Aiken Counties, South Carolina

    SciTech Connect

    Gellici, J.A.; Logan, W.R. )

    1993-03-01

    Preliminary paleontologic, lithologic, and geophysical data from four deep coreholes east of the Savannah River Site in Allendale, Barnwell and Aiken Counties in South Carolina indicate the presence of four Upper Cretaceous formations and seven Tertiary formations in a dip-oriented geologic section. Hydrologic and lithologic data have been used to delineate three aquifer systems along the same section. The Cretaceous units are composed mainly of sand and clay with minor amounts of carbonates. The lowermost unit is correlative with the Cape Fear Formation. The upper three Cretaceous units are correlative with the Lumbee Group (Middendorf, Black Creek, Peedee). Updip units of the Tertiary section are mainly sand and clay, becoming increasingly calcareous downdip. The lower two Tertiary units are correlative with the Black Mingo Group (Ellenton, Williamsburg). Two middle units are correlative with the Orangeburg Group (Congaree, Santee) and the upper three units correlate with the Barnwell Group (Clinchfield, Dry Branch, Tobacco Road). Hydrologic and lithologic data are used to delineate three regional aquifer systems at the downdip terminus of the section; two in the Cretaceous and one in the Tertiary. Updip where the Cretaceous clays cease to act as an effective confining unit, the two aquifer systems coalesce resulting in one Cretaceous and one Tertiary aquifer system. Farther updip the Tertiary confining system pinches out and the entire sedimentary sequence acts as a single aquifer system.

  1. Final report of the Oak Ridge Task Force concerning public health impacts of the off-site contamination in East Fork Poplar Creek and other area streams

    SciTech Connect

    Travis, C.C.; Blaylock, B.G.; Daniels, K.L.; Gist, C.S.; Hoffman, F.O.; McElhaney, R.J.; Weber, C.W.

    1989-08-01

    As a result of operations associated with the Department of Energy (DOE) facilities near Oak Ridge, Tennessee, a nearby creek, East Fork Poplar Creek (EFPC), became contaminated with mercury and trace levels of other metals, organics and radionuclides. An interagency task force, identified as the Oak Ridge Task Force (ORTF) was organized to investigate the extent of off-site environmental contamination of EFPC and other area streams related to the Oak Ridge Reservation, and to determine if any immediate public health impacts might result from such contamination. Four study groups were established by the ORTF to supervise investigations of fisheries, groundwater, soils, surface water, sediment, and floodplains. A fifth study group was established to perform an evaluation of possible public health impacts. The DOE also authorized several organizations to collect and analyze samples and make field measurements needed by the Task Force. The Tennessee Valley Authority (TVA) was authorized to perform an instream contaminant study to determine the extent of contamination of surface water, sediment, fish, and floodplains. The US Geological Survey (USGS) was authorized to determine the extent of groundwater contaminant. Oak Ridge Associated Universities (ORAU) was charged with determining the extent of contamination of the terrestrial foodchain which might be consumed by humans. Oak Ridge National Laboratory (ORNL) was requested to provide assistance in health impact assessments. 19 refs., 12 tabs.

  2. Tectonic analysis and paleo-stress determination of the upper lava section at ODP/IODP site 1256 (East Pacific Ocean)

    NASA Astrophysics Data System (ADS)

    Fontana, Emanuele

    2015-09-01

    Research on the deep sea is of great importance for a better understanding of the mechanism of magma emplacement and the tectonic evolution of oceanic crust. However, details of the internal structure in the upper levels of the oceanic crust are much less complete than that of the more fully studied sub-aerial areas. For the first time, this study proposes a dynamic analysis using the inversion method on core data derived from the drilled basement of the present-day intact oceanic crust at ODP/IODP Site 1256 in the Cocos plate. The research is based on an innovative core reorientation process and combines different stress hypothesis approaches for the analysis of heterogeneous failure-slip data via exploitation of two distinct techniques. From the analysis of the failure-slip data, both techniques produce 5 distinct subsystem datasets. All calculated subsystems are mechanically and geometrically admissible. Interpretation of the results allows the researchers to note a complex local and regional tectonic evolution deriving from the interplay of (1) the ridge push and rotation of both the East Pacific Rise and the Cocos-Nazca Spreading Center, (2) the effect of the slab pull of the Middle America Trench, (3) the influence of lava emplacement mechanisms, and (4) intra-plate deformation.

  3. The Olorgesailie Drilling Project (ODP): a high-resolution drill core record from a hominin site in the East African Rift Valley

    NASA Astrophysics Data System (ADS)

    Dommain, R.; Potts, R.; Behrensmeyer, A. K.; Deino, A. L.

    2014-12-01

    The East African rift valley contains an outstanding record of hominin fossils that document human evolution over the Plio-Pleistocene when the global and regional climate and the rift valley itself changed markedly. The sediments of fossil localities typically provide, however, only short time windows into past climatic and environmental conditions. Continuous, long-term terrestrial records are now becoming available through core drilling to help elucidate the paleoenvironmental context of human evolution. Here we present a 500,000 year long high-resolution drill core record obtained from a key fossil and archeological site - the Olorgesailie Basin in the southern Kenya Rift Valley, well known for its sequence of archeological and faunal sites for the past 1.2 million years. In 2012 two drill cores (54 and 166 m long) were collected in the Koora Plain just south of Mt. Olorgesailie as part of the Olorgesailie Drilling Project (ODP) to establish a detailed climate and ecological record associated with the last evidence of Homo erectus in Africa, the oldest transition of Acheulean to Middle Stone Age technology, and large mammal species turnover, all of which are documented in the Olorgesailie excavations. The cores were sampled at the National Lacustrine Core Facility. More than 140 samples of tephra and trachytic basement lavas have led to high-precision 40Ar/39Ar dating. The cores are being analyzed for a suite of paleoclimatic and paleoecological proxies such as diatoms, pollen, fungal spores, phytoliths, ostracodes, carbonate isotopes, leaf wax biomarkers, charcoal, and clay mineralogy. Sedimentological analyses, including lithological descriptions, microscopic smear slide analysis (242 samples), and grain-size analysis, reveal a highly variable sedimentary sequence of deep lake phases with laminated sediments, diatomites, shallow lake and near shore phases, fluvial deposits, paleosols, interspersed carbonate layers, and abundant volcanic ash deposits. Magnetic susceptibility indicates climatic variation potentially related to precessional cycles.

  4. Delineation of site-specific management zones by fuzzy clustering of soil and topographic attributes: A case study of East Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Saleh, A.; Belal, A. A.

    2014-02-01

    The objective of this study was to define site-specific management zones of 67.2 ha of a wheat pivot field at East of Nile Delta, Egypt for use in precision agriculture based on spatial variability of soil and topographic attributes. The field salinity was analysed by reading the apparent soil electrical conductivity (ECa) with the EM38 sensor horizontally and vertically at 432 locations. The field was sampled for soil attributes systematically with a total of 80 sampling location points. All samples were located using GPS hand held unit. Soil sampling for management zones included soil reaction pH, soil saturation percentage, organic matter, calcium carbonates content, available nitrogen, available phosphorus and available potassium. The field topographic attributes were digital elevation model (DEM), slope, profile curvature, plane curvature, compound topographic index (CTI) and power stream index (PSI). The maps of spatial variability of soil and field topographic attributes were generated using ordinary kriging geostatistical method. Principal component analysis (PCA) was used to determine the most important soil and topographic attributes for representing within-field variability. Principal component analysis of input variables indicated that EM38 horizontal readings (EM38h), soil saturation percentage and digital elevation model were more important attributes for defining field management zones. The fuzzy c-means clustering method was used to divide the field into potential management zones, fuzzy performance index (FPI) and normalized classification entropy (NCE) were used to determine the optimal cluster numbers. Measures of cluster performance indicated no advantage of dividing these fields into more than five management zones. The defined management zones not only provided a better description of the soil properties, but also can direct soil sampling design and provide valuable information for site-specific management in precision agriculture.

  5. TYBO/BENHAM: Model Analysis of Groundwater Flow and Radionuclide Migration from Underground Nuclear Tests in Southwestern Pahute Mesa, Nevada

    SciTech Connect

    Andrew Wolfsberg; Lee Glascoe; Guoping Lu; Alyssa; Olson; Peter Lichtner; Maureen McGraw; Terry Cherry; ,; Guy Roemer

    2002-09-01

    Recent field studies have led to the discovery of trace quantities of plutonium originating from the BENHAM underground nuclear test in two groundwater observation wells on Pahute Mesa at the Nevada Test Site. These observation wells are located 1.3 km from the BENHAM underground nuclear test and approximately 300 m from the TYBO underground nuclear test. In addition to plutonium, several other conservative (e.g. tritium) and reactive (e.g. cesium) radionuclides were found in both observation wells. The highest radionuclide concentrations were found in a well sampling a welded tuff aquifer more than 500m above the BENHAM emplacement depth. These measurements have prompted additional investigations to ascertain the mechanisms, processes, and conditions affecting subsurface radionuclide transport in Pahute Mesa groundwater. This report describes an integrated modeling approach used to simulate groundwater flow, radionuclide source release, and radionuclide transport near the BENHAM and TYBO underground nuclear tests on Pahute Mesa. The components of the model include a flow model at a scale large enough to encompass many wells for calibration, a source-term model capable of predicting radionuclide releases to aquifers following complex processes associated with nonisothermal flow and glass dissolution, and site-scale transport models that consider migration of solutes and colloids in fractured volcanic rock. Although multiple modeling components contribute to the methodology presented in this report, they are coupled and yield results consistent with laboratory and field observations. Additionally, sensitivity analyses are conducted to provide insight into the relative importance of uncertainty ranges in the transport parameters.

  6. MESAFace, a graphical interface to analyze the MESA output

    PubMed Central

    Giannotti, M.; Wise, M.; Mohammed, A.

    2014-01-01

    MESA (Modules for Experiments in Stellar Astrophysics) has become very popular among astrophysicists as a powerful and reliable code to simulate stellar evolution. Analyzing the output data thoroughly may, however, present some challenges and be rather time-consuming. Here we describe MESAFace, a graphical and dynamical interface which provides an intuitive, efficient and quick way to analyze the MESA output. Nature of problem: Find a way to quickly and thoroughly analyze the output of a MESA run, including all the profiles, and have an efficient method to produce graphical representations of the data. Solution method: We created two scripts (to be run consecutively). The first one downloads all the data from a MESA run and organizes the profiles in order of age. All the files are saved as tables or arrays of tables which can then be accessed very quickly by Mathematica. The second script uses the Manipulate function to create a graphical interface which allows the user to choose what to plot from a set of menus and buttons. The information shown is updated in real time. The user can access very quickly all the data from the run under examination and visualize it with plots and tables. Unusual features: Moving the slides in certain regions may cause an error message. This happens when Mathematica is asked to read nonexistent data. The error message, however, disappears when the slides are moved back. This issue does not preclude the good functioning of the interface. Additional comments: The program uses the dynamical capabilities of Mathematica. When the program is opened, Mathematica prompts the user to ”Enable Dynamics”. It is necessary to accept before proceeding. Running time: Depends on the size of the data downloaded, on where the data are stored (hard-drive or web), and on the speed of the computer or network connection. In general, downloading the data may take from a minute to several minutes. Loading directly from the web is slower. For example, downloading a 200MB data folder (a total of 102 files) with a dual-core Intel laptop, P8700, 2 GB of RAM, at 2.53 GHz took about a minute from the hard-drive and about 23 minutes from the web (with a basic home wireless connection). PMID:24563547

  7. Preliminary Map of Landslide Deposits in the Mesa Verde National Park Area, Colorado

    USGS Publications Warehouse

    Carrara, Paul E.

    2009-01-01

    This report presents a preliminary map of landslide deposits in the Mesa Verde National Park area (see map sheet) at a compilation scale of 1:50,000. Landslide is a general term for landforms produced by a wide variety of gravity-driven mass movements, including various types of flows, slides, topples and falls, and combinations thereof produced by the slow to rapid downslope transport of surficial materials or bedrock. The map depicts more than 200 landslides ranging in size from small (0.01 square miles) earthflows and rock slumps to large (greater than 0.50 square miles) translational slides and complex landslides (Varnes, 1978). This map has been prepared to provide a regional overview of the distribution of landslide deposits in the Mesa Verde area, and as such constitutes an inventory of landslides in the area. The map is suitable for regional planning to identify broad areas where landslide deposits and processes are concentrated. It should not be used as a substitute for detailed site investigations. Specific areas thought to be subject to landslide hazards should be carefully studied before development. Many of the landslides depicted on this map are probably stable as they date to the Pleistocene (approximately 1.8-0.011 Ma) and hence formed under a different climate regime. However, the recognition of these landslides is important because natural and human-induced factors can alter stability. Reduction of lateral support (by excavations or roadcuts), removal of vegetation (by fire or development), or an increase in pore pressure (by heavy rains) may result in the reactivation of landslides or parts of landslides.

  8. Characterization of Preferential Flowpaths at the T-Tunnel Complex, Rainier Mesa, Nevada

    NASA Astrophysics Data System (ADS)

    Reeves, D. M.; Schultz, R.; Bingham, C.; Pohlmann, K.; Russell, C.; Chapman, J.

    2007-12-01

    Rainier Mesa (RM), a tuffaceous plateau on the Nevada Test Site, has been the location of numerous subsurface nuclear tests. The tests were conducted in a series of tunnel complexes located approximately 450 m below the top of the mesa and 1000 m above the regional ground water flow system. The tunnels were constructed near the middle of a 690 m sequence of low-permeability bedded and non-welded vitric and zeolitized tuff units. Though these tuff units are nearly saturated, active ground water flow is restricted to perched lenses occurring within poorly connected normal faults linked to recharge pathways. The perched systems vary from 100 to 150 m above the tunnel complexes which suggests that the now-sealed tunnels could enhance connectivity between otherwise isolated preferential flow pathways. This work represents the first stage of radionuclide transport investigations for the T-tunnel complex at RM: the characterization and stochastic generation of preferential pathways based on fault and joint data collected along tunnel transects. Analysis of fault and joint orientations demonstrate that fractures at RM are steeply-dipping and trend approximately NE-SW. A higher degree of spread about the mean strike relative to the mean dip direction results in an elliptical distribution of fracture orientation. A novel method based on a bivariate normal is used as an alternative to the Fisher distribution to generate fracture orientations. The spatial distribution of fractures along transects indicates fractal clustering (D=0.3) with a power-law distribution of fracture spacing (α=1.1). Fault displacement data are used in conjunction with mechanical models of fault growth to infer both the length and vertical extent of large faults. Major faults are deterministic features in the model domain, while a cascade process is used to govern the spatial distribution of background fractures. Assessment of methods for assigning hydraulic conductivity values to the joints and faults are underway.

  9. Mesa 1/sup 0/ x 2/sup 0/ NTMS area, Arizona: data report (abbreviated)

    SciTech Connect

    Cook, J.R.; Koller, G.R.

    1980-09-01

    Surface sediment samples were collected at 713 sites, at a target sampling density of one site per 13 square kilometers. Ground water samples were collected at 365 sites. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Data from ground water and surface water sites include (1) water chemistry measurements (pH, conductivity, and alkalinity) (2) physical measurements where applicable (water temperature, well description, and scintillometer reading) and (3) elemental analyses (U, Al, Br, Cl, Dy, F, Mg, Mn, Na, and V). Helium analyses are given for ground water. Data from sediment sites include (1) stream water chemistry measurements from sites where water was available and (2) elemental analyses for sediment samples (U, Th, Hf, Al, Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulated. Areal distribution maps, histograms, and cumulative frequency plots for most elements; U/Th, U/Hf, U/(Th+Hf), and U/La ratios; and scintillometer readings at sediment sample sites are included on the microfiche. The maximum uranium concentration found in sediments in the Mesa quadrangle was 36.6 ppM. The mean of the logarithms of the uranium concentrations was 0.58, which is equivalent to 3.8 ppM. High uranium concentrations are related to Precambrian granites; however, high log (U/Th) values appear to be related to Tertiary volcanic rocks.

  10. The Implementation of Career Education through the Mesa Center for Career Development.

    ERIC Educational Resources Information Center

    Booth, George, Comp.

    Efforts of the Center for Career Development (Mesa, Arizona) to compare various strategies for promoting available career education materials and services in the Mesa Public Schools (to determine which strategies are more effective in increasing utilization of career education resources) are described. After identifying the career education…

  11. Mesa Verde--A Year-Round High School. A Descriptive Report of 1980-81.

    ERIC Educational Resources Information Center

    Housden, Terry; Holmes, Lynda

    Mesa Verde High School was constructed in 1974 and is the last high school built in the San Juan (California) Unified District. It serves students in grades 9 through 12 and has an open enrollment policy. Mesa Verde operates on a year-round schedule with students divided into three tracks. Basically, each track is in session for 9 weeks and then…

  12. Remotely sensed limonite anomaly on Lordsburg Mesa, New Mexico: possible implications for uranium deposits ( USA).

    USGS Publications Warehouse

    Raines, G.L.; Erdman, J.A.; McCarthy, J.H.; Reimer, G.M.

    1985-01-01

    We have identified a large, anomalously limonitic area in Cenozoic gravels on Lordsburg Mesa near Lordsburg, New Mexico, using Landsat images. Our interpretation of the geophysical and geochemical data suggests the exploration hypothesis that the Lordsburg Mesa limonite anomaly is the surface expression of a chemical trap that may contain concentrations of uranium similar to calcrete-uranium deposits. -from Authors

  13. MESA: Supporting Teaching and Learning about the Marine Environment--Primary Science Focus

    ERIC Educational Resources Information Center

    Preston, Christine

    2010-01-01

    The Marine Education Society of Australasia (MESA) Inc. is a national organisation of marine educators that aims to bring together people interested in the study and enjoyment of coastal and marine environments. MESA representatives and members organise education and interpretation activities in support of schools and communities during a number

  14. 75 FR 46945 - Proposed Collection; Comment Request; Multi-Ethnic Study of Atherosclerosis (MESA) Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-04

    ... Atherosclerosis (MESA) Event Surveillance SUMMARY: In compliance with the requirement of Section 3506(c)(2)(A) of... (MESA) Event Surveillance. Type of Information Request: Renewal (OMB No. 0925-0493). Need and Use of... of appropriate automated, electronic, mechanical, or other technological collection techniques...

  15. MESA: Supporting Teaching and Learning about the Marine Environment--Primary Science Focus

    ERIC Educational Resources Information Center

    Preston, Christine

    2010-01-01

    The Marine Education Society of Australasia (MESA) Inc. is a national organisation of marine educators that aims to bring together people interested in the study and enjoyment of coastal and marine environments. MESA representatives and members organise education and interpretation activities in support of schools and communities during a number…

  16. Stable isotope-based Plio-Pleistocene ecosystem reconstruction of some of the earliest hominid fossil sites in the East African Rift System (Chiwondo Beds, N Malawi)

    NASA Astrophysics Data System (ADS)

    Lüdecke, Tina; Thiemeyer, Heinrich; Schrenk, Friedemann; Mulch, Andreas

    2014-05-01

    The isotope geochemistry of pedogenic carbonate and fossil herbivore enamel is a powerful tool to reconstruct paleoenvironmental conditions in particular when climate change plays a key role in the evolution of ecosystems. Here, we present the first Plio-Pleistocene long-term carbon (δ13C), oxygen (δ18O) and clumped isotope (Δ47) records from pedogenic carbonate and herbivore teeth in the Malawi Rift. These data represent an important southern hemisphere record in the East African Rift System (EARS), a key region for reconstructing vegetation patterns in today's Zambezian Savanna and correlation with data on the evolution and migration of early hominids across the Inter-Tropical Convergence Zone. As our study site is situated between the well-known hominid-bearing sites of eastern and southern Africa in the Somali-Masai Endemic Zone and Highveld Grassland it fills an important geographical gap for early hominid research. 5.0 to 0.6 Ma fluviatile and lacustrine deposits of the Chiwondo Beds (NE shore of Lake Malawi) comprise abundant pedogenic carbonate and remains of a diverse fauna dominated by large terrestrial mammals. These sediments are also home to two hominid fossil remains, a mandible of Homo rudolfensis and a maxillary fragment of Paranthropus boisei, both dated around 2.4 Ma. The Chiwondo Beds therefore document early co-existence of these two species. We evaluate δ13C data from fossil enamel of different suid, bovid, and equid species and contrast these with δ13C and δ18O values of pedogenic carbonate. We complement the latter with clumped isotope soil temperature data. Results of almost 800 pedogenic carbonate samples from over 20 sections consistently average δ13C = -8.5 ‰ over the past 5 Ma with no significant short-term δ13C excursions or long-term trends. The data from molar tooth enamel of nine individual suids of the genera Metridiochoerus, Notochoerus and Nyanzachoerus support these findings with average δ13C = -10.0 ‰. The absence of long-term trends towards more positive δ13C values contrasts the increasing role of C4-grasslands in the southern EARS which is well documented for sites in Ethiopia, Kenya and Tanzania. Our data hence point to regional differences in climate and vegetation dynamics during the Plio-Pleistocene in the EARS and documents persistence of paleoenvironmental conditions in the southern branch of the EARS at times of early hominid evolution.

  17. Southern high-latitude terrestrial climate change during the Palaeocene-Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)

    NASA Astrophysics Data System (ADS)

    Contreras, L.; Pross, J.; Bijl, P. K.; O'Hara, R. B.; Raine, J. I.; Sluijs, A.; Brinkhuis, H.

    2014-07-01

    Reconstructing the early Palaeogene climate dynamics of terrestrial settings in the high southern latitudes is important to assess the role of high-latitude physical and biogeochemical processes in the global climate system. However, whereas a number of high-quality Palaeogene climate records has become available for the marine realm of the high southern latitudes over the recent past, the long-term evolution of coeval terrestrial climates and ecosystems is yet poorly known. We here explore the climate and vegetation dynamics on Tasmania from the middle Palaeocene to the early Eocene (60.7-54.2 Ma) based on a sporomorph record from Ocean Drilling Program (ODP) Site 1172 on the East Tasman Plateau. Our results show that three distinctly different vegetation types thrived on Tasmania under a high-precipitation regime during the middle Palaeocene to early Eocene, with each type representing different temperature conditions: (i) warm-temperate forests dominated by gymnosperms that were dominant during the middle and late Palaeocene (excluding the middle/late Palaeocene transition); (ii) cool-temperate forests dominated by southern beech (Nothofagus) and araucarians that transiently prevailed across the middle/late Palaeocene transition interval (~ 59.5 to ~ 59.0 Ma); and (iii) paratropical forests rich in ferns that were established during and in the wake of the Palaeocene-Eocene Thermal Maximum (PETM). The transient establishment of cool-temperate forests lacking any frost-sensitive elements (i.e. palms and cycads) across the middle/late Palaeocene transition interval indicates markedly cooler conditions, with the occurrence of frosts in winter, on Tasmania during that time. The integration of our sporomorph data with previously published TEX86-based sea-surface temperatures from ODP Site 1172 documents that the vegetation dynamics on Tasmania were closely linked with the temperature evolution in the Tasman sector of the Southwest Pacific region. Moreover, the comparison of our season-specific climate estimates for the sporomorph assemblages from ODP Site 1172 with the TEX86L- and TEX86H-based temperature data suggests a warm bias of both calibrations for the early Palaeogene of the high southern latitudes.

  18. Southern high-latitude terrestrial climate change during the Paleocene-Eocene derived from a marine pollen record (ODP Site 1172, East Tasman Plateau)

    NASA Astrophysics Data System (ADS)

    Contreras, L.; Pross, J.; Bijl, P. K.; O'Hara, R. B.; Raine, J. I.; Sluijs, A.; Brinkhuis, H.

    2014-01-01

    Reconstructing the early Paleogene climate dynamics of terrestrial settings in the high southern latitudes is important to assess the role of high-latitude physical and biogeochemical processes in the global climate system. However, whereas a number of high-quality Paleogene climate records has become available for the marine realm of the high southern latitudes over the recent past, the long-term evolution of coeval terrestrial climates and ecosystems is yet poorly known. We here explore the climate and vegetation dynamics on Tasmania from the middle Paleocene to the early Eocene (60.7-54.2 Ma) based on a sporomorph record from Ocean Drilling Program (ODP) Site 1172 on the East Tasman Plateau. Our results show that three distinctly different vegetation types thrived on Tasmania under a high-precipitation regime during the middle Paleocene to early Eocene, with each type representing different temperature conditions: (i) warm-temperate forests dominated by gymnosperms that were dominant during the middle and late Paleocene; (ii) cool-temperate forests dominated by southern beech (Nothofagus) and araucarians across the middle/late Paleocene transition interval (~59.5 to ~59.0 Ma); and (iii) paratropical forests rich in ferns that were established during and in the wake of the Paleocene-Eocene Thermal Maximum (PETM). The transient establishment of cool-temperate forests lacking any frost-sensitive elements (i.e., palms and cycads) across the middle/late Paleocene transition interval indicates markedly cooler conditions, with the occurrence of frosts in winter, on Tasmania during that time. The integration of our sporomorph data with previously published TEX86-based sea-surface temperatures from ODP Site 1172 documents that the vegetation dynamics on Tasmania were closely linked with the temperature evolution in the Tasman sector of the Southwest Pacific region. Moreover, the comparison of our season-specific climate estimates for the sporomorph assemblages from ODP Site 1172 with the TEX86L- and TEX86H-based temperature data suggests a warm-season bias of both calibrations for the early Paleogene of the high southern latitudes.

  19. The Pleistocene evolution of the East Antarctic Ice Sheet in the Prydz bay region: Stable isotopic evidence from ODP Site 1167

    USGS Publications Warehouse

    Theissen, K.M.; Dunbar, R.B.; Cooper, A. K.; Mucciarone, D.A.; Hoffmann, D.

    2003-01-01

    Ocean Drilling Program Leg 188, Prydz Bay, East Antarctica is part of a larger initiative to explore the Cenozoic history of the Antarctic Ice Sheet through direct drilling and sampling of the continental margins. In this paper, we present stable isotopic results from Ocean Drilling Program (ODP) Site 1167 located on the Prydz Channel Trough Mouth Fan (TMF), the first Antarctic TMF to be drilled. The foraminifer-based ??18O record is interpreted along with sedimentary and downhole logging evidence to reconstruct the Quaternary glacial history of Prydz Bay and the adjacent Lambert Glacier Amery Ice Shelf System (LGAISS). We report an electron spin resonance age date of 36. 9 ?? 3.3 ka at 0.45 m below sea floor and correlate suspected glacial-interglacial cycles with the global isotopic stratigraphy to improve the chronology for Site 1167. The ??18O record based on planktonic (Neogloboquadrina pachyderma (s.)) and limited benthic results (Globocassidulina crassa), indicates a trend of ice sheet expansion that was interrupted by a period of reduced ice volume and possibly warmer conditions during the early-mid-Pleistocene (0.9-1.38 Ma). An increase in ?? 18O values after ??? 900 ka appears to coincide with the mid-Pleistocene climate transition and the expansion of the northern hemisphere ice sheet. The ??18O record in the upper 50 m of the stratigraphic section indicates as few as three glacial-interglacial cycles, tentatively assigned as marine isotopic stages (MIS) 16-21, are preserved since the Brunhes/Matuyama paleomagnetic reversal (780 ka). This suggests that there is a large unconformity near the top of the section and/or that there may have been few extreme advances of the ice sheet since the mid-Pleistocene climate transition resulting in lowered sedimentation rates on the Prydz Channel TMF. The stable isotopic record from Site 1167 is one of the few available from the area south of the Antarctic Polar Front that has been linked with the global isotopic stratigraphy. Our results suggest the potential for the recovery of useful stable isotopic records in other TMFs. ?? 2003 Elsevier B.V. All rights reserved.

  20. Simulated heat-exchanger tubes: DOE Geothermal Test Facility, East Mesa, California

    NASA Astrophysics Data System (ADS)

    Ellis, P. F., II; Anliker, D. M.

    1982-11-01

    A 103 hr corrosion test was performed of two geothermal heat exchanger materials, Allegheny-Ludlum Alloy 29-4 and Alloy 29-4C. Coupons of the two metals were exposed under conditions simulating flow in a geothermal heat exchanger tube. Continuous flow and cyclic exposure tests were made. No signs of localized corrosion were observed in either the base metal, tube weld seam, or heat affected zone. Most coupons show statistically insignificant weight change. A corrosion rate of less than 0.5 mil/yr is indicated. No significant difference in the performance of the two alloys is reported.

  1. Gravity and magnetic study of the Pahute Mesa and Oasis Valley region, Nye County, Nevada

    USGS Publications Warehouse

    Mankinen, Edward A.; Hildenbrand, Thomas G.; Dixon, Gary L.; McKee, Edwin H.; Fridrich, Christopher J.; Laczniak, Randell J.

    1999-01-01

    Regional gravity and aeromagnetic maps reveal the existence of deep basins underlying much of the southwestern Nevada volcanic field, approximately 150 km northwest of Las Vegas. These maps also indicate the presence of prominent features (geophysical lineaments) within and beneath the basin fill. Detailed gravity surveys were conducted in order to characterize the nature of the basin boundaries, delineate additional subsurface features, and evaluate their possible influence on the movement of ground-water. Geophysical modeling of gravity and aeromagnetic data indicates that many of the features may be related to processes of caldera formation. Collapse of the various calderas within the volcanic field resulted in dense basement rocks occurring at greater depths within caldera boundaries. Modeling indicates that collapse occurred along faults that are arcuate and steeply dipping. There are indications that the basement in the western Pahute Mesa - Oasis Valley region consists predominantly of granitic and/or fine-grained siliceous sedimentary rocks that may be less permeable to groundwater flow than the predominantly fractured carbonate rock basement to the east and southeast of the study area. The northeast-trending Thirsty Canyon lineament, expressed on gravity and basin thickness maps, separates dense volcanic rocks on the northwest from less dense intracaldera accumulations in the Silent Canyon and Timber Mountain caldera complexes. The source of the lineament is an approximately 2-km wide ring fracture system with step-like differential displacements, perhaps localized on a pre-existing northeast-trending Basin and Range fault. Due to vertical offsets, the Thirsty Canyon fault zone probably juxtaposes rock types of different permeability and, thus, it may act as a barrier to ground-water flow and deflect flow from Pahute Mesa along its flanks toward Oasis Valley. Within the Thirsty Canyon fault zone, highly fractured rocks may serve also as a conduit, depending upon the degree of alteration and its effect on porosity and permeability. In the Oasis Valley region, other structures that may influence ground-water flow include the western and southern boundaries of the Oasis Valley basin, where the basement abruptly shallows.

  2. Gravity and magnetic study of the Pahute Mesa and Oasis Valley region, Nye County, Nevada

    SciTech Connect

    Dixon, G.L.; Fridrich, C.J.; Hildenbrand, T.G.; Laczniak, R.J.; Mankinen, E.A.; McKee, E.H.

    1999-08-31

    Regional gravity and aeromagnetic maps reveal the existence of deep basins underlying much of the southwestern Nevada volcanic field, approximately 150 km northwest of Las Vegas. These maps also indicate the presence of prominent features (geophysical lineaments) within and beneath the basin fill. Detailed gravity surveys were conducted in order to characterize the nature of the basin boundaries, delineate additional subsurface features, and evaluate their possible influence on the movement of ground water. Geophysical modeling of gravity and aeromagnetic data indicates that many of the features may be related to processes of caldera formation. Collapse of the various calderas within the volcanic field resulted in dense basement rocks occurring at greater depths within caldera boundaries. Modeling indicates that collapse occurred along faults that are arcuate and steeply dipping. There are indications that the basement in the western Pahute Mesa - Oasis Valley region consists predominantly of granitic and/or fine-grained siliceous sedimentary rocks that may be less permeable to ground-water flow than the predominantly fractured carbonate rock basement to the east and southeast of the study area. The northeast-trending Thirsty Canyon lineament, expressed on gravity and basin thickness maps, separates dense volcanic rocks on the northwest from less dense intracaldera accumulations in the Silent Canyon and Timber Mountain caldera complexes. The sources of the lineament is an approximately 2-km wide ring fracture system with step-like differential displacements, perhaps localized on a pre-existing northeast-trending Basin and Range fault. Due to vertical offsets, the Thirsty Canyon faults zone probably juxtaposes rock types of different permeability and, thus, it may act as a barrier to ground-water flow and deflect flow from Pahute Mesa along its flanks toward Oasis Valley. Within the Thirsty Canyon fault zone, highly fractured rocks may serve also as a conduit, depending upon the degree of alteration and its effect on porosity and permeability. In the Oasis Valley region, other structures that may influence ground-water flow include the western and southern boundaries of the Oasis Valley basin, where the basement abruptly shallows.

  3. Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions

    NASA Astrophysics Data System (ADS)

    Paxton, Bill; Marchant, Pablo; Schwab, Josiah; Bauer, Evan B.; Bildsten, Lars; Cantiello, Matteo; Dessart, Luc; Farmer, R.; Hu, H.; Langer, N.; Townsend, R. H. D.; Townsley, Dean M.; Timmes, F. X.

    2015-09-01

    We substantially update the capabilities of the open-source software instrument Modules for Experiments in Stellar Astrophysics (MESA). MESA can now simultaneously evolve an interacting pair of differentially rotating stars undergoing transfer and loss of mass and angular momentum, greatly enhancing the prior ability to model binary evolution. New MESA capabilities in fully coupled calculation of nuclear networks with hundreds of isotopes now allow MESA to accurately simulate the advanced burning stages needed to construct supernova progenitor models. Implicit hydrodynamics with shocks can now be treated with MESA, enabling modeling of the entire massive star lifecycle, from pre-main-sequence evolution to the onset of core collapse and nucleosynthesis from the resulting explosion. Coupling of the GYRE non-adiabatic pulsation instrument with MESA allows for new explorations of the instability strips for massive stars while also accelerating the astrophysical use of asteroseismology data. We improve the treatment of mass accretion, giving more accurate and robust near-surface profiles. A new MESA capability to calculate weak reaction rates “on-the-fly” from input nuclear data allows better simulation of accretion induced collapse of massive white dwarfs and the fate of some massive stars. We discuss the ongoing challenge of chemical diffusion in the strongly coupled plasma regime, and exhibit improvements in MESA that now allow for the simulation of radiative levitation of heavy elements in hot stars. We close by noting that the MESA software infrastructure provides bit-for-bit consistency for all results across all the supported platforms, a profound enabling capability for accelerating MESA's development.

  4. Modules for Experiments in Stellar Astrophysics (MESA): Planets, Oscillations, Rotation, and Massive Stars

    NASA Astrophysics Data System (ADS)

    Paxton, Bill; Cantiello, Matteo; Arras, Phil; Bildsten, Lars; Brown, Edward F.; Dotter, Aaron; Mankovich, Christopher; Montgomery, M. H.; Stello, Dennis; Timmes, F. X.; Townsend, Richard

    2013-09-01

    We substantially update the capabilities of the open source software package Modules for Experiments in Stellar Astrophysics (MESA), and its one-dimensional stellar evolution module, MESA star. Improvements in MESA star's ability to model the evolution of giant planets now extends its applicability down to masses as low as one-tenth that of Jupiter. The dramatic improvement in asteroseismology enabled by the space-based Kepler and CoRoT missions motivates our full coupling of the ADIPLS adiabatic pulsation code with MESA star. This also motivates a numerical recasting of the Ledoux criterion that is more easily implemented when many nuclei are present at non-negligible abundances. This impacts the way in which MESA star calculates semi-convective and thermohaline mixing. We exhibit the evolution of 3-8 M ⊙ stars through the end of core He burning, the onset of He thermal pulses, and arrival on the white dwarf cooling sequence. We implement diffusion of angular momentum and chemical abundances that enable calculations of rotating-star models, which we compare thoroughly with earlier work. We introduce a new treatment of radiation-dominated envelopes that allows the uninterrupted evolution of massive stars to core collapse. This enables the generation of new sets of supernovae, long gamma-ray burst, and pair-instability progenitor models. We substantially modify the way in which MESA star solves the fully coupled stellar structure and composition equations, and we show how this has improved the scaling of MESA's calculational speed on multi-core processors. Updates to the modules for equation of state, opacity, nuclear reaction rates, and atmospheric boundary conditions are also provided. We describe the MESA Software Development Kit that packages all the required components needed to form a unified, maintained, and well-validated build environment for MESA. We also highlight a few tools developed by the community for rapid visualization of MESA star results.

  5. Remote sensing for environmental site screening and watershed evaluation in Utah Mine lands - East Tintic mountains, Oquirrh mountains, and Tushar mountains

    USGS Publications Warehouse

    Rockwell, Barnaby W.; McDougal, Robert R.; Gent, Carol A.

    2005-01-01

    Imaging spectroscopy-a powerful remote-sensing tool for mapping subtle variations in the composition of minerals, vegetation, and man-made materials on the Earth's surface-was applied in support of environmental assessments and watershed evaluations in several mining districts in the State of Utah. Three areas were studied through the use of Landsat 7 ETM+ and Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data: (1) the Tintic mining district in the East Tintic Mountains southwest of Provo, (2) the Camp Floyd mining district (including the Mercur mine) and the Stockton (or Rush Valley) mining district in the Oquirrh Mountains south of the Great Salt Lake, and (3) the Tushar Mountains and Antelope Range near Marysvale. The Landsat 7 ETM+ data were used for initial site screening and the planning of AVIRIS surveys. The AVIRIS data were analyzed to create spectrally defined maps of surface minerals with special emphasis on locating and characterizing rocks and soils with acid-producing potential (APP) and acid-neutralizing potential (ANP). These maps were used by the United States Environmental Protection Agency (USEPA) for three primary purposes: (1) to identify unmined and anthropogenic sources of acid generation in the form of iron sulfide and (or) ferric iron sulfate-bearing minerals such as jarosite and copiapite; (2) to seek evidence for downstream or downwind movement of minerals associated with acid generation, mine waste, and (or) tailings from mines, mill sites, and zones of unmined hydrothermally altered rocks; and (3) to identify carbonate and other acid-buffering minerals that neutralize acidic, potentially metal bearing, solutions and thus mitigate potential environmental effects of acid generation. Calibrated AVIRIS surface-reflectance data were spectrally analyzed to identify and map selected surface materials. Two maps were produced from each flightline of AVIRIS data: a map of iron-bearing minerals and water having absorption features in the spectral region from 0.35 ?m to 1.35 ?m and a map of minerals (including clays, sulfates, micas, and carbonates) having absorptions in the spectral region from 1.45 ?m to 2.51 ?m. Several methods were used to verify the AVIRIS mapping results, including field checking of selected locations with a portable spectrometer, visual inspection of the AVIRIS reflectance spectra, and X-ray diffraction (XRD) analysis of field samples. The maps of iron-bearing minerals derived from analysis of the visible (VIS) and near-infrared (NIR) regions of the electromagnetic spectrum were shown to be more consistently reliable in indicating the presence of jarosite than were the maps generated from analysis of the short-wave infrared (SWIR) region. When present in abundance, phyllosilicate minerals tend to dominate the SWIR and mask the spectral features of jarosite in that wavelength region. The crystal field absorptions of jarosite in the VIS and NIR spectral regions will commonly be present regardless of whether the Fe-OH absorption feature near 2.27 ?m can be detected. For this reason, the VIS and NIR were preferable to the SWIR for the remote spectroscopic identification of jarosite (and other iron-bearing minerals). Large exposures of unmined hydrothermally altered rocks occur throughout the three study areas. These rocks commonly contain sulfide or sulfate minerals that produce sulfuric acid upon subaerial oxidation. The acid may be introduced into local surface and ground water and thus lower the baseline (that is, the premining) pH for a watershed. The three study areas also have widespread exposures of rocks with acid-neutralizing potential. Lithologies containing carbonates and (or) other acid-buffering minerals-such as sedimentary limestones and dolomites and propylitically altered igneous rocks-were mapped with the AVIRIS data throughout the Oquirrh and East Tintic Mountains and locally in the Antelope Range and Tushar Mountains. Because elevated levels o

  6. Differential sensitivity theory applied to the MESA code

    SciTech Connect

    Henninger, R.J. ); Maudlin, P.J.; Harstad, E.N. Los Alamos, National Laboratory, Los Alamos, New Mexico 87545 )

    1994-07-10

    A technique called Differential Sensitivity Theory (DST) is applied to the system of equations solved by the MESA continuum mechanics code. DST uses adjoint technique to determine exact sensitivity derivatives, i.e., if R is a calculation result of interest (response R ) and [alpha][sub i] is a calculational input (parameter [alpha][sub i]), then [alpha]R/[alpha][sub i] is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem [ital all] n sensitivities can be obtained by integrating the solutions from only [ital two] calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics (ACM) code. This work presents the derivation and solution of the appropriate set of adjoint equations for the purpose of computing sensitivities for high-rate two-dimensional, multi-component, high-deformation problems. As an example, results for a flyer plate impact problem are given. [copyright]American Institute of Physics

  7. The Mesa Verde outcrop: Seismic modeling, processing, and interpretation

    SciTech Connect

    Bourgeois, A.; Dequirez, P.Y.; Etienne, G.; Mace, D.; Richard, V.

    1994-12-31

    For a realistic geological model a 2D numerical elastic modeling is carried out. The objectives is, first, a better understanding of the information content of reflection seismic data and, second, to provide synthetic data for testing and evaluating the efficiency of processing and inversion techniques under known conditions. Of particular interest are the small-scale heterogeneities in view of reservoir delineation and characterization. The geologic model is constructed from the Campanian cross-section of the Mesa Verde outcrop (Colorado, USA). A subsurface seismic model buried in a 1D background medium is defined from the 2D Mesa Verde geologic model by assigning P-wave and S-wave velocities and densities to each geologic facies. This seismic model is used as input for a fully elastic seismic simulating a realistic marine survey of 280 shots. The synthetic seismograms are calculated by a finite-difference method. The data are processed in a conventional way; then a target-related post-processing is performed including stratigraphic inversion. Finally, a geologic significance is given to waveform and amplitude variations in the estimated P-impedances.

  8. MTF comparisons between mesa and planar focal plane detector structures

    NASA Astrophysics Data System (ADS)

    Perley, Mitchell; Wehner, Justin; Buell, Dave; Micali, Jason; McCorkle, Joe; Rehfield, Mark; Williams, Dave; Dixon, Andrew; Malone, Neil

    2013-09-01

    Raytheon Vision Systems (RVS) has developed scanning, high-speed (<3klps), all digital, with on-chip Analog-to-Digital Conversion (ADC), mid-wave infrared (MWIR 3-5mm) focal plane arrays (FPA) with excellent modulation transfer function (MTF) performance. Using secondary ion mass spectrometry (SIMS) data and detailed models of the mesa geometry, RVS modeled the predicted detector MTF performance of detectors. These detectors have a mesa structure and geometry for improved MTF performance compared to planar HgCdTe and InSb detector structures and other similar detector structures such as nBn. The modeled data is compared to measured MTF data obtained from edge spread measurements and shows good agreement, Figure 1. The measured data was obtained using a custom advanced test set with 1µm precision alignment and automatic data acquisition for report generation in less than five minutes per FPA. The measured MTF values of 83 unique parts, Figure 2, had a standard deviation of 0.0094 and a mean absolute deviation of 0.0066 at half Nyquist frequency, showing excellent process repeatability and a design that supports high MTF with good repeatability.

  9. Increasing seismic activity at 9deg50'N on the East Pacific Rise RIDGE 2000 Integrated Studies Site from October 2003 through April 2004

    NASA Astrophysics Data System (ADS)

    Weekly, R. T.; Tolstoy, M.; Waldhauser, F.; Bohnenstiehl, D. R.; Kim, W.

    2005-12-01

    Monitoring of micro-seismicity within the bull's-eye region of the R2K ISS at 9deg49'N - 9deg51'N on the East Pacific Rise has been ongoing since October 2003. Results from the first deployment (October 2003 - April 2004) will be presented with hypocenters determined using relative-relocation techniques. Analysis shows that there is a gradual and ongoing increase in the rate of activity over the 7 months of the deployment. Mean event rates increase from 31 events/day for the first quarter of the deployment period, to 55, 105, and 131 events per day for the 2nd, 3rd and 4th quarters, respectively. This gradual increase in activity suggests long-term changes in the magma body or changes in the hydrothermal cracking front. Preliminary analysis and event counts for the 2004-2005 deployment will be presented to assess whether or not the build up in activity seen in 2003-2004 continued. Numerous brief swarms are observed throughout the deployment and their locations will be studied relative to temporal changes in the vent temperature monitoring as well as variations in the fluid chemistry (see Von Damm et al., same session). Early analysis suggests two dominant areas of recurrent activity, between M-vent and Bio-9 and between Bio-9 and Tube-worm pillar. The exceptionally well-characterized and monitored seafloor at this site allows for unprecedented correlation of observed seismic activity with local biology, geology, geochemical and hydrothermal monitoring. As results from different monitoring activities continue to come in, a detailed understanding of the linkages should emerge.

  10. Completion Report for Wells ER-20-8 and ER-20-8#2 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2011-02-28

    Wells ER-20-8 and ER-20-8#2 were drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada National Security Site (formerly Nevada Test Site), Nye County, Nevada. The holes were drilled in July and August 2009, as part of the Pahute Mesa Phase II drilling program. The primary purpose of these wells was to provide detailed hydrogeologic information in the Tertiary volcanic section that will help address uncertainties within the Pahute Mesa–Oasis Valley hydrostratigraphic framework model. They may also be used as long-term monitoring wells.

  11. Completion Report for Well ER-EC-13 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2011-05-31

    Well ER-EC-13 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada National Security Site (formerly Nevada Test Site), Nye County, Nevada. The well was drilled in October 2010 as part of the Pahute Mesa Phase II drilling program. A main objective was to provide detailed hydrogeologic information for the Fortymile Canyon composite unit hydrostratigraphic unit in the Timber Mountain moat area, within the Timber Mountain caldera complex, that will help address uncertainties within the Pahute Mesa–Oasis Valley hydrostratigraphic framework model. This well may also be used as a long-term monitoring well.

  12. Work plan for mercury treatability study in upper east fork Popular Creek at DOE`s Y-12 Site in support of the Reduction of Mercury in Plant Effluent program (RMPE)

    SciTech Connect

    1998-02-01

    Over the past ten years the Department of Energy Y-12 Site`s Reduction of Mercury in Plant Effluents (RMPE) project has carried out an aggressive investigative program of identifying sources of mercury which are influencing the levels of mercury in Upper East Fork Popular Creek (UEFPC) and exiting the site at Station 17. The driver for these activities has been and continues to be the site`s National Pollution Discharge Elimination Permit (NPDES). This permit establishes certain remedial actions, the schedule for these actions and requires that the mercury in the creek be equal to or less than 5 grams per day by December 31, 1998 and the concentration in the creek be equal to or less than 0.12 {mu} grams per liter on the last day of the permit, April 27, 2000.

  13. Magnetic fabric investigation of the oligocene Fish Canyon and Sapinero Mesa tuffs: Examination of effects of topography on ignimbrite emplacement, Southern Rocky Mountain Volcanic Field, Colorado

    NASA Astrophysics Data System (ADS)

    Martin, Michael

    Exposures of two laterally extensive ignimbrites in the northern part of the Southern Rocky Mountain Volcanic Field (SRMVF), Colorado, allow examination of the emplacement mechanisms of these pyroclastic deposits as a function of deposition on irregular preexisting topography using magnetic fabric techniques. The Sapinero Mesa and Fish Canyon tuffs are major components of the SRMVF and were emplaced on highly irregular paleotopography. This study examines how the Sapinero Mesa and Fish Canyon tuffs were emplaced on different topographic features. A total of 34 sites were collected and analyzed for determination of magnetic fabrics, to interpret transport directions, through measurements of anisotropy of magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent magnetization (AARM). Analyses indicate inferred transport directions that locally differ from the assumed regional north-northwest transport direction. The discrepancies between regional and localized flow directions suggest a transport-driven response to local topography attending deposition.

  14. Modeling unsaturated-zone flow at Rainier Mesa as a possible analog for a future Yucca Mountain

    SciTech Connect

    Gauthier, J.H.

    1998-01-01

    Rainier Mesa is structurally similar to Yucca Mountain, and receives precipitation similar to the estimated long-term average for Yucca Mountain. Tunnels through the unsaturated zone at Rainier Mesa have encountered perched water and, after the perched water was drained, flow in fractures and faults. Although flow observations have been primarily qualitative, Rainier Mesa hydrology is a potential analog for Yucca Mountain hydrology in a wetter climate. In this paper, a groundwater flow model that has been used in the performance assessment of Yucca Mountain--the weeps model--is applied to Rainier Mesa. The intent is to gain insight in both Rainier Mesa and the weeps flow model.

  15. Geology, geochronology, and geochemistry of basaltic flows of the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra, central New Mexico

    USGS Publications Warehouse

    Maldonado, F.; Budahn, J.R.; Peters, L.; Unruh, D.M.

    2006-01-01

    The geochronology, geochemistry, and isotopic compositions of basaltic flows erupted from the Cat Hills, Cat Mesa, Wind Mesa, Cerro Verde, and Mesita Negra volcanic centres in central New Mexico indicate that each of these lavas had unique origins and that the predominant mantle involved in their production was an ocean-island basalt type. The basalts from Cat Hills (0.11 Ma) and Cat Mesa (3.0 Ma) are similar in major and trace element composition, but differences in MgO contents and Pb isotopic values are attributed to a small involvement of a lower crustal component in the genesis of the Cat Mesa rocks. The Cerro Verde rock is comparable in age (0.32 Ma) to the Cat Hills lavas, but it is more radiogenic in Sr and Nd, has higher MgO contents, and has a lower La/Yb ratio. This composition is explained by the melting of an enriched mantle source, but the involvement of another crustal component cannot be disregarded. The Wind Mesa rock is characterized by similar age (4.01 Ma) and MgO contents, but it has enriched rare-earth element contents compared with the Cat Mesa samples. These are attributed to a difference in the degree of partial melting of the Cat Mesa source. The Mesita Negra rock (8.11 Ma) has distinctive geochemical and isotopic compositions that suggest a different enriched mantle and that large amounts of a crustal component were involved in generating this magma. These data imply a temporal shift in magma source regions and crustal involvement, and have been previously proposed for Rio Grande rift lavas. ?? 2006 NRC Canada.

  16. Ground-water resources of the Florida Mesa area, La Plata County, Colorado

    USGS Publications Warehouse

    Robson, S.G.; Wright, W.G.

    1995-01-01

    Rapid population growth in La Plata County, Colorado, has increased the demand for ground water in the Florida Mesa area. This report was prepared in cooperation with La Plata County to provide needed information about the geology, extent, thickness, and depth of the aquifers in the area; sources of ground-water recharge and discharge; direction of ground-water movement; water-level changes; and water quality in the alluvial and bedrock aquifers. Ground water in the study area is present in bedrock formations and in terrace deposits on Florida Mesa. Porous or fractured sandstone beds that contain bedrock aquifers are present near land surface along the northern margin of the study area and are present at depths less than 3,000 feet throughout the study area. Terrace deposits as much as 200 feet thick and consisting of gravel, sand, silt, and clay are present on Florida Mesa. The terrace deposits and the upper part of the underlying Animas and Nacimiento Formations form the principal aquifer under the mesa. Ground water under the mesa is supplied from precipitation and irrigation water. A small part of the precipitation and irrigation water on the mesa percolates to depth in the soil and recharges the aquifer. Irrigation water is the largest source of this recharge. Water levels in the aquifer can decline because of a reduction in irrigation recharge, or because of an increase in well pumping. Because irrigation recharge is so much larger than pumping, changes in recharge can have a much larger effect on ground-water levels than can changes in pumping. Factors that tend to increase ground-water recharge and thereby increase or maintain ground- water levels include: maintaining large rates of surface-water diversion onto Florida Mesa, reducing surface flow off the mesa, increasing use of ponds and spreading basins to promote infiltration, and irrigating by use of flood irrigation. The general direction of ground-water movement on the mesa is from the northern part of the mesa to the south, southwest, and southeast. Most ground water discharges from the mesa to the Animas and Florida Rivers through seeps and springs along the margin of the mesa. Winter water levels in wells generally are lower than summer water levels because of the lack of irrigation recharge during the fall and winter. Potable water of low dissolved-solids concentration is present in the shallow parts of most aquifers.

  17. MESAFace, a graphical interface to analyze the MESA output

    NASA Astrophysics Data System (ADS)

    Giannotti, M.; Wise, M.; Mohammed, A.

    2013-04-01

    MESA (Modules for Experiments in Stellar Astrophysics) has become very popular among astrophysicists as a powerful and reliable code to simulate stellar evolution. Analyzing the output data thoroughly may, however, present some challenges and be rather time-consuming. Here we describe MESAFace, a graphical and dynamical interface which provides an intuitive, efficient and quick way to analyze the MESA output. Catalogue identifier: AEOQ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOQ_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 19165 No. of bytes in distributed program, including test data, etc.: 6300592 Distribution format: tar.gz Programming language: Mathematica. Computer: Any computer capable of running Mathematica. Operating system: Any capable of running Mathematica. Tested on Linux, Mac, Windows XP, Windows 7. RAM: Recommended 2 Gigabytes or more. Supplementary material: Additional test data files are available. Classification: 1.7, 14. Nature of problem: Find a way to quickly and thoroughly analyze the output of a MESA run, including all the profiles, and have an efficient method to produce graphical representations of the data. Solution method: We created two scripts (to be run consecutively). The first one downloads all the data from a MESA run and organizes the profiles in order of age. All the files are saved as tables or arrays of tables which can then be accessed very quickly by Mathematica. The second script uses the Manipulate function to create a graphical interface which allows the user to choose what to plot from a set of menus and buttons. The information shown is updated in real time. The user can access very quickly all the data from the run under examination and visualize it with plots and tables. Unusual features: Moving the slides in certain regions may cause an error message. This happens when Mathematica is asked to read nonexistent data. The error message, however, disappears when the slides are moved back. This issue does not preclude the good functioning of the interface. Additional comments: The program uses the dynamical capabilities of Mathematica. When the program is opened, Mathematica prompts the user to “Enable Dynamics”. It is necessary to accept before proceeding. Running time: Depends on the size of the data downloaded, on where the data are stored (hard-drive or web), and on the speed of the computer or network connection. In general, downloading the data may take from a minute to several minutes. Loading directly from the web is slower. For example, downloading a 200 MB data folder (a total of 102 files) with a dual-core Intel laptop, P8700, 2 GB of RAM, at 2.53 GHz took about a minute from the hard-drive and about 23 min from the web (with a basic home wireless connection).

  18. Geology of the Wilkes Land Sub-basin and Stability of the East Antarctic Ice Sheet: Insights from rock magnetism at IODP Site U1361

    NASA Astrophysics Data System (ADS)

    Tauxe, L.; Sugisaki, S.; Jimenez-Espejo, F. J.; Cook, C. P.; van de Flierdt, T.; Iwai, M.; Escutia, C.

    2014-12-01

    IODP Expedition 318 drilled Site U1361 on the continental rise offshore of the Wilkes sub-glacial basin. The goal was to reconstruct the stability of the East Antarctic Ice Sheet (EAIS) during Neogene warm periods. Teasing out the paleoenvironmental implications is essential for understanding the evolution of the EAIS. Anisotropy of magnetic susceptibility (AMS) is sensitive to differential compaction and other rock magnetic parameters like isothermal remanence and anhysteretic remanence are very sensitive to changes in the terrestrial source region. In general, highly anisotropic layers correspond with laminated clay-rich units, while more isotropic layers are bioturbated and have less clay. Layers enriched in diatoms are associated with the latter, which also have higher Ba/Al ratios indicating higher productivity. Higher anisotropy layers have lower porosity and moisture contents and have fine grained magnetic mineralogy dominated by magnetic. Higher anisotropy layers are dominated by maghemite, supporting the suggestion by Cook et al. (2013) of different source regions during low and high productivity times. They tied the two facies to the coastal outcrops of the Lower Paleozoic granitic terranes and the Ferrar Large Igneous Province in the more inland Wilkes Subglacial Basin respectively. Here we present evidence for a third geological unit, one eroded at the boundaries between the high and low clay zones with a "hard" (hematite) dominated magnetic mineralogy. This unit likely outcrops in the Wilkes sub-glacial basin and could be hydrothermally altered Beacon sandstone similar to that detected by Craw and Findlay (1984) in Taylor Valley or the equivalent to the Elatina Formation in the Adelaide Geosyncline in Southern Australia (Schmidt and Williams, 2013). Cook, C. P., van de Flierdt, T., Williams, T., Hemming, S. R., Iwai, M., Kobayashi, M., Jimenez-Espejo, F., Escutia, C., Gonzalez, J., Khim, B. K., McKay, R., Passchier, S., Bohaty, S., Riesselman, C. R., Tauxe, L., Sugisaki, S., Lopez Galindo, A., Patterson, M. O., Sangiorgi, F., Pierce, E. L., Brinkhuis, H., and Scientists, I. E., 2013, Nature Geoscience, v. 6, p. 765-769. Craw, D., and Findlay, R. H., 1984, New Zealand Jour. Geol. Geophys., v. 27, p. 465-475. Schmidt, P. W., and Williams, G. E., 2013, Global and Planetary Change, v. 110, p. 289-301.

  19. Deep reflection structure imaged by the 2008 3D seismic reflection Survey at the RIDGE- 2000 East Pacific Rise Integrated Studies Site

    NASA Astrophysics Data System (ADS)

    Nedimović, M. R.; Carbotte, S. M.; Mutter, J. C.; Canales, P. J.; Carton, H.; Aghaei, O.; Marjanović, M.; Newman, K. R.; Hu, M.; Stowe, L.

    2008-12-01

    The first multi-source and multi-streamer 3D seismic reflection experiment carried out using academic resources was done aboard the R/V Marcus G. Langseth in Summer 2008 during cruise MGL0812. The targeted area was the RIDGE-2000 Integrated Studies Site at the East Pacific Rise. Our primary 3D survey grid extends from about 9° 57'N to 9° 42'N, with a smaller grid just to the south covering approximately from 9° 40'N to 9° 37.5'N. Additionally, about 1 and 0.5 km wide across-ridge-axis swaths of data were collected at 9° 36'N and 9°30'N respectively, as well as an along-ridge-axis swath about 1 km wide and extending from 10° 05'N to 9° 40'N. We here focus on a preliminary analysis of the reflection structure imaged within the lower crust and uppermost mantle. Moho reflection arrivals are imaged through much of the investigated area. The character of Moho reflection events varies from simple, single reflection wavelet to more complex arrivals indicating spatial changes in structure within the Moho transition zone. Particularly strong Moho reflections are observed in the southern half of the main 3D grid. In places, Moho reflection event appears to extend across the ridge axis potentially suggesting "zero-age" Moho development. Weak Moho arrivals are found at the north end of the main 3D box and within the smaller box to the south. Most notable place lacking Moho reflections is the Lamont seamount area where Moho is not observed on either side of the ridge axis, although the area lacking Moho reflections is wider on the western ridge flank. Further south, along the across-ridge-axis swaths, Moho reflections again become more pronounced. A suit of what mostly appear to be reflection events is recognized between the AMC and Moho. Many of them do not appear to be multiples, and their origin is not well understood. Possible origins for these events include: lower boundary of the AMC, S-converted waves, and lower crustal melt lenses. Along sections of the two 3D grids, possible subhorizontal, low signal-to-noise ratio mantle reflections are identified 1-2 s after the Moho reflection. Arrivals potentially originating from lower crustal melt sills, zero-age Moho, and mantle reflections are all of critical importance for understanding fast spreading centers. In the years to follow, we will put significant effort to analyze the identified arrivals in order to determine their origin and find where they fit within the crustal accretionary puzzle.

  20. Geology of the Wilkes land sub-basin and stability of the East Antarctic Ice Sheet: Insights from rock magnetism at IODP Site U1361

    NASA Astrophysics Data System (ADS)

    Tauxe, L.; Sugisaki, S.; Jiménez-Espejo, F.; Escutia, C.; Cook, C. P.; van de Flierdt, T.; Iwai, M.

    2015-02-01

    IODP Expedition 318 drilled Site U1361 on the continental rise offshore of Adélie Land and the Wilkes subglacial basin. The objective was to reconstruct the stability of the East Antarctic Ice Sheet (EAIS) during Neogene warm periods, such as the late Miocene and the early Pliocene. The sedimentary record tells a complex story of compaction, and erosion (thus hiatuses). Teasing out the paleoenvironmental implications is essential for understanding the evolution of the EAIS. Anisotropy of magnetic susceptibility (AMS) is sensitive to differential compaction and other rock magnetic parameters like isothermal remanence and anhysteretic remanence are very sensitive to changes in the terrestrial source region. In general, highly anisotropic layers correspond with laminated clay-rich units, while more isotropic layers are bioturbated and have less clay. Layers enriched in diatoms are associated with the latter, which also have higher Ba/Al ratios consistent with higher productivity. Higher anisotropy layers have lower porosity and moisture contents and have fine grained magnetic mineralogy dominated by maghemite, the more oxidized form of iron oxide, while the lower anisotropy layers have magnetic mineralogies dominated by magnetite. The different magnetic mineralogies support the suggestion based on isotopic signatures by Cook et al. (2013) of different source regions during low productivity (cooler) and high productivity (warmer) times. These two facies were tied to the coastal outcrops of the Lower Paleozoic granitic terranes and the Ferrar Large Igneous Province in the more inland Wilkes Subglacial Basin respectively. Here we present evidence for a third geological unit, one eroded at the boundaries between the high and low clay zone with a "hard" (mostly hematite) dominated magnetic mineralogy. This unit likely outcrops in the Wilkes subglacial basin and could be hydrothermally altered Beacon sandstone similar to that detected by Craw and Findlay (1984) in Taylor Valley or the equivalent to the Elatina Formation in the Adelaide Geosyncline in Southern Australia (Schmidt and Williams, 2013). Correlation of the "hard" events with global oxygen isotope stacks of Zachos et al. (2001) and Lisiecki and Raymo (2005) suggest that the source region was eroded during times with higher global ice volume.

  1. Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona: 2011-2012

    USGS Publications Warehouse

    Macy, Jamie P.; Unema, Joel A.

    2014-01-01

    The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area typically is between 6 and 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2011 to September 2012. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2011, total groundwater withdrawals were 4,480 acre-ft, industrial withdrawals were 1,390 acre-ft, and municipal withdrawals were 3,090 acre-ft. Total withdrawals during 2011 were about 39 percent less than total withdrawals in 2005 because of Peabody Western Coal Company’s discontinued use of water to transport coal in a slurry. From 2010 to 2011 total withdrawals increased by 11 percent; industrial withdrawals increased by approximately 19 percent, and total municipal withdrawals increased by 8 percent. From 2011 to 2012, annually measured water levels in the Black Mesa area declined in 8 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was -0.1 feet. Water levels declined in 9 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.0 feet. From the prestress period (prior to 1965) to 2012, the median water-level change for 34 wells in both the confined and unconfined areas was -13.4 feet; the median water-level changes were -2.1 feet for 16 wells measured in the unconfined areas and -39.1 feet for 18 wells measured in the confined area. Spring flow was measured at four springs in 2012. Flow fluctuated during the period of record for Burro and Unnamed Spring near Dennehotso, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s and discharge at Unnamed Spring near Dennehotso has fluctuated for the period of record. Trend analysis for discharge at Moenkopi and Pasture Canyon Springs yielded a slope significantly different from zero. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2010), Dinnebito Wash near Sand Springs 09401110 (1993 to 2010), Polacca Wash near Second Mesa 09400568 (1994 to 2010), and Pasture Canyon Springs 09401265 (2004 to 2010). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, and there are no significant statistical trends in groundwater discharge. In 2012, water samples collected from 10 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 10 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied significantly since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

  2. Groundwater, Surface-Water, and Water-Chemistry Data, Black Mesa Area, Northeastern Arizona-2008-2009

    USGS Publications Warehouse

    Macy, Jamie P.

    2010-01-01

    The N aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area, which is typically about 6 to 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2008 to September 2009. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2008, total groundwater withdrawals were 4,110 acre-feet, industrial withdrawals were 1,210 acre-ft, and municipal withdrawals were 2,900 acre-ft. Total withdrawals during 2008 were about 44 percent less than total withdrawals in 2005. From 2007 to 2008 total withdrawals decreased by 4 percent, industrial withdrawals increased by approximately 3 percent, but total municipal withdrawals decreased by 6 percent. From 2008 to 2009, annually measured water levels in the Black Mesa area declined in 8 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was -0.1 feet. Water levels declined in 11 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.2 feet. From the prestress period (prior to 1965) to 2009, the median water-level change for 34 wells in both the confined and unconfined area was -11.8 feet. Also, from the prestress period to 2009, the median water-level changes were -1.6 feet for 16 wells measured in the unconfined areas and -36.7 feet for 18 wells measured in the confined area. Spring flow was measured at three springs in 2009. Flow fluctuated during the period of record, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro spring has remained constant since it was first measured in 1998. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2008), Dinnebito Wash near Sand Springs 09401110 (1993 to 2008), Polacca Wash near Second Mesa 09400568 (1994 to 2008), and Pasture Canyon Springs 09401265 (August 2004 to 2008). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2009, water samples collected from 6 wells and 3 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 6 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring have varied for the period of record, but there is no trend in the data.

  3. Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2009–10

    USGS Publications Warehouse

    Macy, Jamie P.; Brown, Christopher R.

    2011-01-01

    The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area is typically between 6 and 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2009 to September 2010. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2009, total groundwater withdrawals were 4,230 acre-ft, industrial withdrawals were 1,390 acre-ft, and municipal withdrawals were 2,840 acre-ft. Total withdrawals during 2009 were about 42 percent less than total withdrawals in 2005 because of Peabody Western Coal Company's discontinued use of water in a coal slurry used for transporting coal. From 2008 to 2009 total withdrawals increased by 3 percent and industrial withdrawals increased by approximately 15 percent, but total municipal withdrawals decreased by 2 percent. From 2009 to 2010, annually measured water levels in the Black Mesa area declined in 7 of 16 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.1 foot. Water levels declined in 12 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.3 foot. From the prestress period (prior to 1965) to 2010, the median water-level change for 34 wells in both the confined and unconfined area was -13.9 feet. Also, from the prestress period to 2009, the median water-level changes were -0.8 foot for 16 wells measured in the unconfined areas and -38.7 feet for 18 wells measured in the confined area. Spring flow was measured at four springs in 2010. Flow fluctuated during the period of record, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring and Unnamed Spring near Dennehotso has remained relatively constant since they were first measured in the 1980s. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2009), Dinnebito Wash near Sand Springs 09401110 (1993 to 2009), Polacca Wash near Second Mesa 09400568 (1994 to 2009), and Pasture Canyon Springs 09401265 (2004 to 2009). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2010, water samples collected from 11 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 11 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

  4. Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2012–2013

    USGS Publications Warehouse

    Macy, Jamie P.; Truini, Margot

    2016-01-01

    The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area typically is between 6 and 14 inches per year.The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2012 to September 2013. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry.In calendar year 2012, total groundwater withdrawals were 4,010 acre-ft, industrial withdrawals were 1,370 acre-ft, and municipal withdrawals were 2,640 acre-ft. Total withdrawals during 2012 were about 45 percent less than total withdrawals in 2005 because of Peabody Western Coal Company’s discontinued use of water to transport coal in a coal slurry pipeline. From 2011 to 2012 total withdrawals decreased by 10 percent; industrial withdrawals decreased by approximately 1 percent, and total municipal withdrawals decreased by 15 percent.From 2012 to 2013, annually measured water levels in the Black Mesa area declined in 6 of 16 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.8 feet. Water levels declined in 5 of 16 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.3 feet. From the prestress period (prior to 1965) to 2013, the median water-level change for 34 wells in both the confined and unconfined areas was -13.5 feet; the median water-level changes were -0.8 feet for 16 wells measured in the unconfined areas and -51.0 feet for 16 wells measured in the confined area.Spring flow was measured at four springs in 2013; Burro, Unnamed Spring near Dennehotso, Moenkopi School, and Pasture Canyon Springs. Flow fluctuated during the period of record for Burro and Unnamed Springs near Dennehotso, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s and discharge at Unnamed Spring near Dennehotso has fluctuated for the period of record at each spring. Trend analysis for discharge at Moenkopi School and Pasture Canyon Springs showed a decreasing trend.Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2013), Dinnebito Wash near Sand Springs 09401110 (1993 to 2013), Polacca Wash near Second Mesa 09400568 (1994 to 2013), and Pasture Canyon Springs 09401265 (2004 to 2013). Median winter flows (November through February) from these sites for each water year were used as an index of the amount of groundwater discharge. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge.In 2013, water samples collected from 12 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 12 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 13 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied significantly since the early 1980s. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record with no increasing or decreasing trend in the data.

  5. Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona - 2010-2011

    USGS Publications Warehouse

    Macy, Jamie P.; Brown, Christopher R.; Anderson, Jessica R.

    2012-01-01

    The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area is typically between 6 to 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2010 to September 2011. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2010, total groundwater withdrawals were 4,040 acre-ft, industrial withdrawals were 1,170 acre-ft, and municipal withdrawals were 2,870 acre-ft. Total withdrawals during 2010 were about 42 percent less than total withdrawals in 2005 because of Peabody Western Coal Company's discontinued use of water to transport coal in a slurry. From 2009 to 2010 total withdrawals decreased by 5 percent; industrial withdrawals decreased by approximately 16 percent, and total municipal withdrawals increased by 1 percent. From 2010 to 2011, annually measured water levels in the Black Mesa area declined in 7 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.0 foot. Water levels declined in 11 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.7 foot. From the prestress period (prior to 1965) to 2011, the median water-level change for 33 wells in both the confined and unconfined areas was -15.0 feet. Also, from the prestress period to 2011, the median water-level changes were -1.2 foot for 15 wells measured in the unconfined areas and -41.2 feet for 18 wells measured in the confined area. Spring flow was measured at three springs in 2011. Flow fluctuated during the period of record, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2010), Dinnebito Wash near Sand Springs 09401110 (1993 to 2010), Polacca Wash near Second Mesa 09400568 (1994 to 2010), and Pasture Canyon Springs 09401265 (2004 to 2010). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2011, water samples collected from 11 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 11 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

  6. Dislocation Reduction in HgCdTe Mesa Structures Formed on CdTe/Si

    NASA Astrophysics Data System (ADS)

    Simingalam, Sina; Pattison, James; Chen, Yuanping; Wijewarnasuriya, Priyalal; Rao, Mulpuri V.

    2016-04-01

    Mercury cadmium telluride (MCT) epilayers have been grown on CdTe/Si using molecular beam epitaxy and 8-μm-deep mesa structures formed using plasma etching. Following previous work done on etching mesas and subjecting material to thermal cycle annealing, we set out to determine the limits and underlying physics of dislocation reduction in mesa-etched and annealed MCT. This paper describes the dependence of dislocation reduction on anneal time, cycle annealing, temperature, and etch depth. We show dislocation density reduction below 3 × 105 cm-2 in 10-μm-wide, long-bar mesas along the [0bar{1}1] orientation with only a 5-min anneal at 400°C.

  7. Application of the MESA reactive hydrocode to space vehicle explosive ordnance devices

    NASA Technical Reports Server (NTRS)

    Goldstein, Selma

    1993-01-01

    The construction of detailed computational models of the dynamic behavior of various explosive ordnance devices used on space vehicles is discussed. The following topics are presented in viewgraph form: numerical methods, explosives and detonations, and the MESA computer code.

  8. Relations of Principal Components Analysis Site Scores to Algal-Biomass, Habitat, Basin-Characteristics, Nutrient, and Biological-Community Data in the Whitewater River and East Fork White River Basins, Indiana, 2002

    USGS Publications Warehouse

    Caskey, Brian J.; Frey, Jeffrey W.; Lowe, B. Scott

    2007-01-01

    Data were gathered from May through September 2002 at 76 randomly selected sites in the Whitewater River and East Fork White River Basins, Indiana, for algal biomass, habitat, nutrients, and biological communities (fish and invertebrates). Basin characteristics (land use and drainage area) and biolog-ical-community attributes and metric scores were determined for the basin of each sampling site. Yearly Principal Compo-nents Analysis site scores were calculated for algal biomass (periphyton and seston). The yearly Principal Components Analysis site scores for the first axis (PC1) were related using Spearman's rho to the seasonal algal-biomass, basin-charac-teristics, habitat, seasonal nutrient, and biological-community attribute and metric score data. The periphyton PC1 site score was not significantly related to the nine habitat or 12 nutrient variables examined. One land-use variable, drainage area, was negatively related to the periphyton PC1. Of the 43 fish-community attributes and metrics examined, the periphyton PC1 was negatively related to one attribute (large-river percent) and one metric score (car-nivore percent metric score). It was positively related to three fish-community attributes (headwater percent, pioneer percent, and simple lithophil percent). The periphyton PC1 was not statistically related to any of the 21 invertebrate-community attributes or metric scores examined. Of the 12 nutrient variables examined two were nega-tively related to the seston PC1 site score in two seasons: total Kjeldahl nitrogen (July and September), and TP (May and September). There were no statistically significant relations between the seston PC1 and the five basin-characteristics or nine habitat variables examined. Of the 43 fish-community attributes and metrics examined, the seston PC1 was positively related to one attribute (headwater percent) and negatively related to one metric score (large-river percent metric score) . Of the 21 invertebrate-community attributes and metrics exam-ined, the seston PC1 was negatively related to one metric score (number of individuals metric score). To understand how the choice of sampling sites might have affected the results, an analysis of the drainage area and land use was done. The sites selected in the Whitewater River Basin were generally small drainage basins; compared to Whitewater River Basin sites, the sites selected in the East Fork White River Basin were generally larger drainage basins. Although both basins were dominated by agricultural land use the Whitewater River Basin sites had more land in agriculture than the East Fork White River Basin sites. The values for nutrients (nitrate, total Kjeldahl nitrogen, total nitrogen, and total phosphorus) and chlorophyll a (per-iphyton and seston) were compared to published U.S. Environmental Protection Agency (USEPA) values for Aggregate Nutrient Ecoregions VI and IX and USEPA Level III Ecore-gions 55 and 71. Several nutrient values were greater than the 25th percentile of published USEPA values. Chlorophyll a (periphyton and seston) values were either greater than the 25thpercentile of published USEPA values or they extended data ranges in the Aggregate Nutrient and Level III Ecore-gions. If the values for the 25th percentile as proposes by the USEPA were adopted as nutrient water-quality criteria, many samples in the Whitewater River and East Fork White River Basins would have exceeded the criteria.

  9. Ground-Water, Surface-Water, and Water-Chemistry Data, Black Mesa Area, Northeastern Arizona-2005-06

    USGS Publications Warehouse

    Truini, Margot; Macy, J.P.

    2007-01-01

    The N aquifer is the major source of water in the 5,400 square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use and the needs of a growing population. Precipitation in the Black Mesa area averages about 6 to 14 inches per year. The water monitoring program in the Black Mesa area began in 1971 and is designed to provide information about the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected for the monitoring program in the Black Mesa area from January 2005 to September 2006. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2005, ground-water withdrawals in the Black Mesa area totaled 7,330 acre-feet, including ground-water withdrawals for industrial (4,480 acre-feet) and municipal (2,850 acre-feet) uses. From 2004 to 2005, total withdrawals increased by less than 2 percent, industrial withdrawals increased by approximately 3 percent, and total municipal withdrawals increased by 0.35 percent. From 2005 to 2006, annually measured water levels in the Black Mesa area declined in 10 of 13 wells in the unconfined areas of the N aquifer, and the median change was -0.5 foot. Measurements indicated that water levels declined in 12 of 15 wells in the confined area of the aquifer, and the median change was -1.4 feet. From the prestress period (prior to 1965) to 2006, the median water-level change for 29 wells was -8.5 feet. Median water-level changes were -0.2 foot for 13 wells in the unconfined areas and -46.6 feet for 16 wells in the confined area. Ground-water discharges were measured once in 2005 and once in 2006 at Moenkopi School Spring and Burro Spring. Discharge decreased by 3.5 percent at Moenkopi School Spring and by 15 percent at Burro Spring. During the period of record at each spring, discharges fluctuated; a decreasing trend was apparent. Continuous records of surface-water discharge in the Black Mesa area have been collected from streamflow gages at the following sites: Moenkopi Wash (1976 to 2005), Dinnebito Wash (1993 to 2005), Polacca Wash (1994 to 2005), Pasture Canyon Spring (August 2004 to December 2005), and Laguna Creek (1996 to 2005). Median flows during November, December, January, and February of each water year were used as an index of the amount of ground-water discharge to the above named sites. For the period of record at each streamflow-gaging station, the median winter flows have decreased for Moenkopi Wash, Dinnebito Wash, and Polacca Wash. There is not a long enough period of record for Pasture Canyon Spring and Laguna Creek was discontinued at the end of December 2005. In 2006, water samples were collected from 6 wells and 2 springs in the Black Mesa area and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 111 to 588 milligrams per liter. Water samples from 5 of the wells and both of the springs had less than 500 milligrams per liter of dissolved solids. Trends in the chemistry of water samples from the 6 wells show the Pi?on NTUA 1 and Peabody 9 wells increasing in dissolved solids, Forest Lake NTUA 1 and Peabody 2 wells decreasing in dissolved solids, and Kykotsmovi PM2 and Keams Canyon PM2 wells show a steady trend. Increasing trends in dissolved-solids, chloride, and sulfate concentrations were evident from the more than 11 years of data for the 2 springs.

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

    USGS Publications Warehouse

    Stevens, C.H.; Stone, P.

    2009-01-01

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

  11. Continued investigations of the occurrence of water in Pahute Mesa emplacement holes

    SciTech Connect

    Hershey, R.L.; Brikowski, T.H.

    1995-04-01

    Periodically, water has been observed in emplacement boreholes drilled for underground testing of nuclear weapons at Pahute Mesa, Nevada Test Site, and is often at levels elevated above the predicted local water table. Water which may provide a means to transport residual radionuclides away from weapon tests may originate as fluids introduced during drilling, from naturally perched groundwater draining into the borehole, or from penetration of the local groundwater table. Lithium-bromide (Li-Br) tracer is being used to evaluate both the origin and movement of these borehole waters. The drilling fluid used to drill the final 100 meters of borehole U-19bh was chemically labeled with LiBr tracer. Lack of significant increase in borehole Br inventory over time indicates that standing water in U-9bh is not returned drilling fluid. Possible sources for the standing water are drilling fluid infiltrated above the bottom 100 in or natural water from a perched or shallower-than-expected saturated zone. The minimum detectable Darcy velocity of water passing through U-19bh is 0.3 m/yr. Borehole U-19bk has a water level approximately 50 in above the predicted pre-drilling water level. Initial water samples were collected from U-19bk to characterize the borehole water quality prior to adding the tracer. The major-ion analytical results of U-19bk along with historical water quality analyses of Water Well 20 and water well UE-19c show that all three waters are similar in character and therefore the water in U-19bk may be either residual drilling fluids originating from Water Well 20 and UE-19c or naturally occurring Pahute Mesa groundwater. LiBr tracer was added to the U-19bk borehole and samples for tracer analysis were collected one month later. For the one month period, no detectable loss of Br was observed. Over this short time period, the minimum detectable Darcy velocity is 10.6 m/yr.

  12. Geological investigations in the U12b.03 and U12b.04 tunnels, Nevada Test Site

    USGS Publications Warehouse

    Diment, W.H.; Wilmarth, V. R.; McKeown, F.A.; Dickey, D.D.; Hinrichs, E.N.; Botinelly, T.; Roach, C.H.; Byers, F.M.; Hawley, C.C.; Izett, G.A.; Clebsch, Alfred

    1959-01-01

    The U12b.03 and .04 tunnels are part of the U12b (Rainier) tunnel complex that was driven northwestward from the steep east slope of Rainier Mesa (a prominent topographic feature in the northwest part of the Test Site (fig . 2)). The U12b.03 tunnel trends north from a point about 980 feet from the portal of the U12b tunnel (fig. 3). The U12b.03 tunnel consists of 620 feet of tunnel, two alcoves, and a shot chamber. The tunnel is irregular, ranging from 6 to 10 feet in width, and 6 to 9 feet in height. The shot chamber at the north end of the tunnel is 22 feet on each sidee The vertical and minimum cover over the shot chamber are 610 and 510 feet, respectively.

  13. Groundwater-silicates Reaction Kinetics in the Navajo Sandstone Aquifer, Black Mesa, Arizona (Invited)

    NASA Astrophysics Data System (ADS)

    Zhu, C.

    2009-12-01

    Despite numerous studies of soil profiles and watersheds for critical zone processes, the studies of reaction kinetics in groundwater systems are relatively a few. Yet, aquifers are major sites for water-rock interaction, and a significant segment of the hydrological cycle and global elemental cycling. In this presentation, I will show a multi-discipline study of the Navajo sandstone aquifer at Black Mesa, Arizona. The aeolian sandstone represents some simplest lithology, and the study area has unusually abundant hydrologic, geochemical, isotopic, and paleoclimate data. Solute fluxes along flow paths are supplemented by travel time bounded by 14C and excess 4-He data, from which orders of magnitude estimates of the in situ silicate dissolution rates were calculated. These rates show two to five orders of magnitude slower than those from laboratory experiments at comparable temperature and pH and at far from equilibrium conditions, and are much slower than those derived from studies of soils and watersheds. Data from some new analytical and microscopic methods show that the reaction kinetics are complex. Stable Si isotopes of dissolved Si in groundwater along a 100 km flow path show 2 per mil variation and as low as -1.42‰, representing the most negative dissolved Si isotope composition so far found for natural waters. Near atomic scale transmission electron microscopy show a thin (~ 10 nm) amorphous layer is present on naturally weathered K-feldspars in the aquifer, which requires re-consideration of the details of surface reaction controlled mechanism. However, the new hypothesis of strongly coupled dissolution and precipitation reactions that we have been advancing in recent years appear to be able to explain part of the well-known apparent field-lab discrepancy. The slow precipitation of secondary minerals raised the groundwater saturation state with respect to feldspars to close to equilibrium, and thus retard the feldspar dissolution rates. Our recent laboratory experiments that complement the field study supports the hypothesis. Zhu, C. (2005) In situ feldspar dissolution rates in an aquifer. Geochimica et Cosmochimica Acta v. 69, no.6, 1435-1453, 2005. Zhu, C. Veblen, D.R., Blum, A.E, Chipera, S. (2006) Naturally weathered feldspar surfaces in the Navajo Sandstone aquifer, Black Mesa, Arizona: Electron microscopic characterization. Geochimica et Cosmochimica Acta v. 70, no.18, 4600-4616, 2006 doi:10.1016/j.gca.2006.07.013. Georg, R. B., Zhu, C. Reynolds, R.C., and Halliday, A.N. (2009) Stable silicon isotopes of groundwater, feldspars, and clay coatings in the Navajo Sandstone aquifer, Black Mesa, Arizona, USA. Geochimica et Cosmochimica Acta, v.73, 229-2241. Fu, Q., P ‡Lu, H. ‡Konishi, R. Dilmore, H. Xu, W. E. Seyfried, Jr., and C. Zhu (2009) Coupled alkali-feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems: 1. New Experimental Data at 200°C and 300 bars. Chemical Geology, 91(3), 955-964. Zhu, C., and ‡Lu, P. (2009) Alkali Feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems: 3. Saturation States of Product Minerals and Reaction Paths. Geochimica et Cosmochimica Acta. v.73, p.3171-3120. doi: 10.1016/j.gca.2009.03.015.

  14. Survey of radon and radon daughter concentrations in selected Rainier Mesa tunnels

    SciTech Connect

    Fauver, D.N.

    1987-01-01

    A survey of radon and radon daughter concentrations (RDCs) in selected tunnels on Rainier Mesa at the Nevada Test Site (NTS) was conducted as a part of the underground testing program at NTS. Measurements were taken in three tunnels, N, T, and G. Results of preliminary measurements indicate that N and T Tunnels have low RDCs, i.e., 0.01 WL (working level) (3% of the EPA standard), with normal ventilation conditions. However, it was demonstrated that RDCs can rise to relatively high levels, i.e., 0.24 WL when ventilation rates are significantly lowered. The radon daughter concentrations measured in G Tunnel were an order of magnitude higher than those in N and T Tunnels. The average RDC in the rock mechanics drift (the ''worst-case'' location in G Tunnel) was 0.13 WL with a range from 0.07 WL to 0.23 WL. Elevated RDCs found in the rock mechanics drift of G Tunnel seemed to be attributable to a lower ventilation rate in conjunction with the more highly fractured nature of the ''welded tuff'' rock formation in which the incline drift was mined. By increasing the ventilation rate, a 60% reduction in RDCs from an average of 0.13 Wl to an average of 0.05 WL was achieved.

  15. Analysis of tracer responses in the BULLION Forced-Gradient Experiment at Pahute Mesa, Nevada

    SciTech Connect

    Paul W. Reimus; Marc J. Haga

    1999-10-01

    This report presents an analysis of the tracer data from the BULLION forced-gradient experiment (FGE) conducted on Pahute Mesa at the Nevada Test Site from June 2, 1997 through August 28, 1997, for the Underground Test Area (UGTA) Program. It also serves to document the polystyrene microsphere data from the FGE. The FGE involved the injection of solute and colloid tracers into wells ER-20-6 No. 1 and ER-20-6 No. 2 while ER-20-6 No. 3 was pumped at approximately 116 gallons per minute (gpm). The experimental configuration and test design are described briefly in this report; more details are provided elsewhere (IT, 1996, 1997, 1998). The tracer responses in the various wells yielded valuable information about transport processes such as longitudinal dispersion, matrix diffusion and colloid transport in the hydrogeologic system in the vicinity of the BULLION nuclear test cavity. Parameter values describing these processes are derived from the semi-analytical model interpretations presented in this report. A companion report (IT, 1998) presents more detailed numerical modeling interpretations of the solute tracer responses.

  16. East Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image shows the East African nations of Ethiopia, Eritrea, and Somalia, as well as portions of Kenya, Sudan, Yemen, and Saudi Arabia. Dominating the scene are the green Ethiopian Highlands. With altitudes as high as 4,620 meters (15,157 feet), the highlands pull moisture from the arid air, resulting in relatively lush vegetation. In fact, coffee-one of the world's most prized crops-originated here. To the north (above) the highlands is Eritrea, which became independent in 1993. East (right) of Ethiopia is Somalia, jutting out into the Indian Ocean. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) captured this true-color image on November 29, 2000. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  17. Middle East

    SciTech Connect

    Hemer, D.O.; Mason, J.F.; Hatch, G.C.

    1981-10-01

    Petroleum production in Middle East countries during 1980 totaled 6,747,719,000 bbl or an average rate of 18,436,390,000 bbl/d, down 13.9% from 1979. Increases were in Saudi Arabia and Syria. Significant decreases occurred in Iraq, Iran, Kuwait, and Turkey. New discoveries were made in Abu Dhabi, Iran, Saudi Arabia, Sharjah, and Oman. New areas were explored in Bahrain, Oman, Syria, and Yemen. 9 figures, 16 tables.

  18. Factors Controlling Pre-Columbian and Early Historic Maize Productivity in the American Southwest, Part 2: The Chaco Halo, Mesa Verde, Pajarito Plateau/Bandelier, and Zuni Archaeological Regions

    USGS Publications Warehouse

    Benson, L.V.

    2011-01-01

    Chemical and nutrient analyses of 471 soil samples from 161 sites within four archaeological regions (Pajarito Plateau/Bandelier, Zuni, Mesa Verde, and the Chaco Halo) were combined with historical climate data in order to evaluate the agricultural productivity of each region. In addition, maize productivity and field-life calculations were performed using organic-nitrogen (N) values from the upper 50 cm of soil in each region and a range (1-3%/year) of N-mineralization rates. The endmember values of this range were assumed representative of dry and wet climate states. With respect to precipitation and heat, the Pajarito Plateau area has excellent agricultural potential; the agricultural potentials of the Zuni and Mesa Verde regions are good; and the agricultural potential of the Chaco Halo is poor. Calculations of N mineralization and field life indicate that Morfield Valley in Mesa Verde should be able to provide 10 bu/ac of maize for decades (without the addition of N) when organic N-mineralization rates exceed 2%. Productivity and field-life potential decrease in the following order: Zuni, Mesa Verde, Bandelier, Chaco Halo. The Chaco Halo is very unproductive; e. g., 10 bushels per acre can be achieved within the Halo only from soils having the highest organic N concentration (third quartile) and which undergo the highest rate (3%) of N mineralization. ?? 2010 US Government.

  19. Geohydrology and effects of water use in the Black Mesa area, Navajo and Hopi Indian Reservations, Arizona

    USGS Publications Warehouse

    Eychaner, James H.

    1983-01-01

    The N aquifer is the main source of water in the 5,400-square-mile Black Mesa area in the Navajo and Hopi Indian Reservations in northeastern Arizona. The N aquifer consists of the Navajo Sandstone and parts of the underlying Kayenta Formation and Wingate Sandstone of Jurassic and Triassic age. Maximum saturated thickness of the aquifer is about 1,050 feet in the northwestern part of the area, and the aquifer thins to extinction to the southeast. Water is under confined conditions in the central 3,300 square miles of the area. To the east, north, and west of Black Mesa, the aquifer is exposed at the surface, and water is unconfined. The aquifer was in equilibrium before about 1965. Recharge of about 13,000 acre-feet per year was balanced primarily by discharge near Moenkopi Wash and Laguna Creek and by evapotranspiration. At least 180 million acre-feet of water was in storage. The estimated average hydraulic conductivity of the aquifer is 0.65 foot per day. The confined storage coefficient is estimated to be about 0.0004 where the aquifer is thickest, and the estimated unconfined storage coefficient ranges from 0.10 to 0.15. Ground-water withdrawals that averaged 5,300 acre-feet per year from 1976 to 1979 have caused water levels to decline in wells in the confined part of the aquifer. Withdrawals include an average of 3,700 acre-feet per year to supply a coal-slurry pipeline from a coal mine on Black Mesa. Six observation wells equipped with water-level recorders have been used to monitor aquifer response. The water level in one well 32 miles south of the mine declined 17 feet from 1972 through 1979 and 3.5 feet during 1979. A mathematical model of the N aquifer was developed and calibrated for equilibrium and nonequilibrium conditions. The model was used in part to improve estimates of aquifer characteristics and the water budget, and it successfully reproduced the observed response of the aquifer through 1979. The model results indicate that about 95 percent of the 44,000 acre-feet of water pumped from 1965 to 1979 was withdrawn from storage, but the reduction amounted to less than 0.03 percent of total storage. Water-level declines through 1979 were estimated to be more than 100 feet in an area of 200 square miles. Four projections of future water-level changes were made using the model. The most probable projection indicates that water-level declines would exceed 100 feet in an area of 440 square miles by 2001. Most of the decline would be recovered within a few years if withdrawals at the mine ceased. By 1990, however, municipal-supply pumpage is expected to exceed pumpage at the mine, and this pumpage would continue to have significant impacts on water levels in the Black Mesa area.

  20. Geology of the Horse Range Mesa quadrangle, Colorado

    USGS Publications Warehouse

    Cater, Fred W., Jr.; Bush, A.L.; Bell, Henry, III; Withington, C.F.

    1953-01-01

    The Horse Range Mesa quadrangle is one of eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of the quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore to large, tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear to be related to certain sedimentary strictures in sandstones of favorable composition.

  1. Eruptive vents for the Burro Mesa Rhyolite, Big Bend National Park, Trans-Pecos Texas

    SciTech Connect

    Holt, G.S.; Parker, D.F. . Dept. of Geology)

    1993-02-01

    Detailed mapping of field relations and flow direction of the Burro Mesa Rhyolite (BMR) have identified vent localities at Burro Mesa, Kit Mountain, Cerro Castellan, Trap Mountain, and Goat Mountain, and the suggest the presence of additional, as yet unlocated, centers of eruption. This work confirms recent interpretations that BMR rocks were not erupted from the Pine Canyon caldera, but were instead erupted from isolated feeder localities in the Burro Mesa-Cerro Castellan area. At the Burro Mesa locality, the BMR contains a lower sparsely-porphyritic lava, a central porphyritic ash-flow tuff, and an upper abundantly-porphyritic lava. At all other mapped localities, only sparsely-porphyritic lava and Wasp Springs Flow Breccia (WSFB) are present. Two vents at Burro Mesa represent sources for separate BMR flows, as well as WSFB, which consists of numerous surge deposits with interbedded ash-flow tuff. Flow directional data suggests a third unlocated vent for abundantly-porphyritic lava in the SE region of Burro Mesa. Flow direction data also suggest that the SW end of Kit Mountain was a source for sparsely-porphyritic lava. A feeder dike at Cerro Castellan cuts up through the WSFB, flaring near the top into a volcanic dome of sparsely-porphyritic lava at the top of the mountain. This cross-cutting relationship was present at most vent localities. Mapping and flow direction data of BMR from vents and other localities suggest that the BMR consists of a discontinuous belt of individual domes, which trend in a southwesterly direction from Burro Mesa to Cerro Castellan.

  2. View facing east of top of quarry wall with forge ...

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

    View facing east of top of quarry wall with forge site in foreground - Granite Hill Plantation, Quarry No. 4, South side of State Route 16, 1.3 miles northeast east of Sparta, Sparta, Hancock County, GA

  3. Completion Report for Well ER-EC-14, Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    2013-03-05

    Well ER-EC-14 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Management Operations Underground Test Area (UGTA) Activity at the Nevada National Security Site (NNSS; formerly Nevada Test Site), Nye County, Nevada. The well was drilled in September and October 2012, as part of the Central and Western Pahute Mesa Corrective Action Unit Phase II drilling program. The primary purpose of the well was to provide detailed hydrogeologic information for the Fortymile Canyon composite hydrostratigraphic unit in the Timber Mountain moat area, within the Timber Mountain caldera complex, that will help address uncertainties within the Pahute Mesa–Oasis Valley hydrostratigraphic framework model. The main 55.9-centimeter (cm) hole was drilled to a total depth of 325.5 meters (m) and cased with 40.6-cm casing to 308.1 m. The hole diameter was then decreased to 37.5 cm, and drilling continued to a total depth of 724.8 m. The completion casing string, set to the depth of 690.9 m, consists of 16.8-cm stainless-steel casing hanging from 19.4-cm carbon-steel casing. The stainless-steel casing has two slotted intervals open to the Rainier Mesa Tuff. Two piezometer strings were installed in Well ER-EC-14. Both piezometer strings, each with one slotted interval, consist of 6.0-cm carbon-steel tubing at the surface, then cross over to 7.3-cm stainless-steel tubing just above the water table. The shallow piezometer string was landed at 507.8 m, and the deep piezometer string was landed at 688.6 m. Both piezometer strings are set to monitor groundwater within moderately to densely welded Rainier Mesa Tuff. Data collected during and shortly after hole construction include composite drill cuttings samples collected every 3.0 m, various geophysical logs, water quality (including tritium and other radionuclides) measurements, and water level measurements. The well penetrated 15.2 m of alluvium and 709.6 m of Tertiary volcanic rocks. The stratigraphy and general lithology were not as expected due to the position of Well ER-EC-14 relative to the buried caldera margins of the Timber Mountain caldera complex. The well is located inside the Rainier Mesa caldera, but outside the younger Ammonia Tanks caldera. On November 5, 2012, a preliminary fluid level in the shallow piezometer string was measured at the depth of 311.8 m. This water level depth was taken before installation of the bridge plug (to be placed within the main completion casing to separate the two slotted zones). Well development, hydrologic testing, and sampling, will be conducted at a later date. No tritium above levels detectable by field methods were encountered in this hole. All Fluid Management Plan (FMP) requirements for Well ER-EC-14 were met. Analysis of monitoring samples and FMP confirmatory samples indicated that fluids generated during drilling at Well ER-EC-14 met the FMP criteria for discharge to an unlined sump or designated infiltration area. All sanitary and hydrocarbon waste generated was properly handled and disposed of.

  4. Homoepitaxial and Heteroepitaxial Growth on Step-Free SiC Mesas

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Powell, J. Anthony

    2004-01-01

    This article describes the initial discovery and development of new approaches to SiC homoepitaxial and heteroepitaxial growth. These approaches are based upon the previously unanticipated ability to effectively supress two-dimensional nucleation of 3C-SiC on large basal plane terraces that form between growth steps when epitaxy is carried out on 4H- and 6H-SiC nearly on-axis substrates. After subdividing the growth surface into mesa regions, pure stepflow homoeptixay with no terrace nucleation was then used to grow all existing surface steps off the edges of screw-dislocation-free mesas, leaving behind perfectly on-axis (0001) basal plane mesa surfaces completely free of atomic-scale steps. Step-free mesa surfaces as large as 0.4 mm x 0.4 mm were experimentally realized, with the yield and size of step-free mesas being initally limited by substrate screw dislocations. Continued epitaxial growth following step-free surface formation leads to the formation of thin lateral cantilevers that extend the step-free surface area from the top edge of the mesa sidewalls. By selecting a proper pre-growth mesa shape and crystallographic orientation, the rate of cantilever growth can be greatly enhanced in a web growth process that has been used to (1) enlarge step-free surface areas and (2) overgrow and laterally relocate micropipes and screw dislocations. A new growth process, named step-free surface heteroepitaxy, has been developed to achieve 3C-SiC films on 4H- and 6H-SiC substrate mesas completely free of double positioning boundary and stacking fault defects. The process is based upon the controlled terrace nucleation and lateral expansion of a single island of 3C-SiC across a step-free mesa surface. Experimental results indicate that substrateepilayer lattice mismatch is at least partially relieved parallel to the interface without dislocations that undesirably thread through the thickness of the epilayer. These results should enable realization of improved SiC homojunction and heterojunction devices. In addition, these experiments offer important insights into the nature of polytypism during SiC crystal growth.

  5. CVD Growth of 3C-SiC on 4H/6H Mesas

    SciTech Connect

    Neudeck,P.; Trunek, A.; Spry, D.; Powell, J.; Du, H.; Skowronski, M.; Huang, X.; Dudley, M.

    2006-01-01

    This article describes growth and characterization of the highest quality reproducible 3C-SiC heteroepitaxial films ever reported. By properly nucleating 3C-SiC growth on top of perfectly on-axis (0001) 4H-SiC mesa surfaces completely free of atomic scale steps and extended defects, growth of 3C-SiC mesa heterofilms completely free of extended crystal defects can be achieved. In contrast, nucleation and growth of 3C-SiC mesa heterofilms on top of 4H-SiC mesas with atomic-scale steps always results in numerous observable dislocations threading through the 3C-SiC epilayer. High-resolution X-ray diffraction (HRXRD) and high resolution cross-sectional transmission electron microscopy (HRXTEM) measurements indicate non-trivial, in-plane, lattice mismatch between the 3C and 4H layers. This mismatch is somewhat relieved in the step-free mesa case via misfit dislocations confined to the 3C/4H interfacial region without dislocations threading into the overlying 3C-SiC layer. These results indicate that the presence or absence of steps at the 3C/4H heteroepitaxial interface critically impacts the quality, defect structure, and relaxation mechanisms of single-crystal heteroepitaxial 3C-SiC films.

  6. CFD Growth of 3C-SiC on 4H/6H Mesas

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Trunek, Andrew J.; Spry, David J.; Powell, J. Anthony; Du, Hui; Skowronski, Marek; Huang, XianRong; Dudley, Michael

    2006-01-01

    This article describes growth and characterization of the highest quality reproducible 3C-SiC heteroepitaxial films ever reported. By properly nucleating 3C-SiC growth on top of perfectly on-axis (0001) 4H-SiC mesa surfaces completely free of atomic scale steps and extended defects, growth of 3C-SiC mesa heterofilms completely free of extended crystal defects can be achieved. In contrast, nucleation and growth of 3C-SiC mesa heterofilms on top of 4H-SiC mesas with atomic-scale steps always results in numerous observable dislocations threading through the 3C-SiC epilayer. High-resolution X-ray diffraction and transmission electron microscopy measurements indicate non-trivial in-plane lattice mismatch between the 3C and 4H layers. This mismatch is somewhat relieved in the step-free mesa case via misfit dislocations confined to the 3C/4H interfacial region without dislocations threading into the overlying 3C-SiC layer. These results indicate that the presence or absence of steps at the 3C/4H heteroepitaxial interface critically impacts the quality, defect structure, and relaxation mechanisms of single-crystal heteroepitaxial 3C-SiC films.

  7. 25. First floor, east wall bathroom, looking east Veterans ...

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

    25. First floor, east wall bathroom, looking east - Veterans Administration Center, Officers Duplex Quarters, 5302 East Kellogg (Legal Address); 5500 East Kellogg (Common Address), Wichita, Sedgwick County, KS

  8. Adipokines and the Right Ventricle: The MESA-RV Study

    PubMed Central

    Harhay, Michael O.; Kizer, Jorge R.; Criqui, Michael H.; Lima, João A. C.; Tracy, Russell; Bluemke, David A.; Kawut, Steven M.

    2015-01-01

    Objective Obesity is associated with changes in both right (RV) and left (LV) ventricular morphology, but the biological basis of this finding is not well established. We examined whether adipokine levels were associated with RV morphology and function in a population-based multiethnic sample free of clinical cardiovascular disease. Methods We examined relationships of leptin, resistin, TNF-α, and adiponectin with RV morphology and function (from cardiac MRI) in participants (n = 1,267) free of clinical cardiovascular disease from the Multi-Ethnic Study of Atherosclerosis (MESA)-RV study. Multivariable regressions (linear, quantile [25th and 75th] and generalized additive models [GAM]) were used to examine the independent association of each adipokine with RV mass, RV end-diastolic volume (RVEDV), RV end-systolic volume (RVESV), RV stroke volume (RVSV) and RV ejection fraction (RVEF). Results Higher leptin levels were associated with significantly lower levels of RV mass, RVEDV, RVESV and stroke volume, but not RVEF, after adjustment for age, gender, race, height and weight. These associations were somewhat attenuated but still significant after adjustment for traditional risk factors and covariates, and were completely attenuated when correcting for the respective LV measures. There were no significant interactions of age, gender, or race/ethnicity on the relationship between the four adipokines and RV structure or function. Conclusions Leptin levels are associated with favorable RV morphology in a multi-ethnic population free of cardiovascular disease, however these associations may be explained by a yet to be understood bi-ventricular process as this association was no longer present after adjustment for LV values. These findings complement the associations previously shown between adipokines and LV structure and function in both healthy and diseased patients. The mechanisms linking adipokines to healthy cardiovascular function require further investigation. PMID:26348768

  9. Evolution of Lacustrine Environments on Mars and Their Significance: The Case for the Brazos Lakes and East Terra Meridiani Basins as Landing Sites for Surveyor 2001

    NASA Astrophysics Data System (ADS)

    Cabrol, N. A.; Grin, E. A.

    1999-01-01

    Ancient Martian lacustrine environments must be considered as primary targets to explore on Mars. Terrestrial studies show that lakes are exceptional sites to keep the record of the evolution of climate, geology, water and life. Finding this record is also the principal objective of the Mars Surveyor Program. This record encompasses changes at local, regional and global scales. Lacustrine sediments provide critical information about all events occurring in the lake catchment area. They are also a locus of complex chemical processes, concentration for life and favorable sites for fossilization processes to take place. We proposed two candidate-sites in the Schiaparelli Crater region responding to this high-priority scientific objective at the June 1999 meeting in Buffalo, NY. The two sites are located in the Sinus Sabeus quadrangle, are well documented by MOC images, and are among the best evidence yet of a Martian past lacustrine activity. We develop their case as high-priority sites for the 01' mission.

  10. M.E.S.A, not Just a Seat at the Table: a Chicano Geology Student's Experience with Investigative Field Research

    NASA Astrophysics Data System (ADS)

    Ponce-Zepeda, M. M.

    2011-12-01

    The MESA (math, engineering, science achievement) program in California engages educationally disadvantaged students, primarily minority groups, providing the opportunity to excel in math and science and graduate with math-based degrees. MESA at East Los Angeles Community College selected me, a returning 24 year-old Chicano student, for the SCEC (Southern California Earthquake Center) summer internship at Utah State University (USU). The project coordinators assigned me to a group with three other undergraduate geology students from across the continent and from a variety of socioeconomic backgrounds to investigate geothermal systems in the Salton Trough and northern Utah. The peer-driven field work transformed student to investigator by forcing each participant to be responsible for the success of the entire group. In this environment, I rose to expectations along with my fellow interns managing a detailed field notebook, sampling, planning routes, level logger maintenance, and x-ray diffractometer analysis interpretation, among other things. Mentorship from and challenges proposed by the USU project advisor further built on this scaffolding of field experience. First hand fieldwork provides a battery of beneficial skills that many undergraduate geology students, especially at the two- year college level, rarely get an opportunity to participate in. The advantage of including non-traditional students from two- year colleges allows for a dynamic research network nationwide. Key sample collection by the East Los Angeles College (ELAC) Geology Club, a student- run club at an inner city community college, facilitated ongoing examination by collecting mud samples from gryphons and mudpots in the Salton Trough and testing temperature, pH levels, electrical conductivity, and total dissolved solids in the field. The samples were sent back to students at USU for further analysis. This collaborative effort is symbiotic as sharing the sampling responsibility allowed USU to save funds and provided ELAC students with the opportunity to gain field- sampling experience. The collaboration that took place allowed community college students to gain confidence in new sampling skills, and students based out of Utah to continue an ongoing study. By sharing the opportunity to conduct fieldwork more students are able to engage in the learning process and contribute to scientific discovery. This feeling of contribution is extremely important to the retention of students in the geosciences. Ultimately, thanks to MESA, this Chicano geology-major gained the confidence and background knowledge necessary to ask critical questions and understand complex concepts that will be the basis for the successful completion of a least a Bachelor of Science degree in geology, and the pursuit of further education.

  11. The preliminary study of autophagy induction of SA and MeSA by confocal

    NASA Astrophysics Data System (ADS)

    Yun, Lijuan; Chen, Wenli

    2010-02-01

    Autophagy appears to be a highly conserved process from unicellular to multicellular eukaryotes which contributes to the equilibrium of intracelluar environment. While it would be harmful to the cells when it is excessive by inducing programmed cell death (PCD). It is a protein degradation process in which cells recycle cytoplasmic contents when subjected to environmental stress conditions or during certain stages of development. Previous studies have demonstrated autophagy can be induced during abiotic or biotic stresses. salicylic acid (SA) and methyl salicytic (MeSA) are endogenous signal molecules. We found SA and MeSA can induce autophagy in Arabidopsis thaliana respectively. While autophagy was not induced by SA or MeSA in tobacco suspension cells under the same concentration and period. The differences in stuctures or physiological states may contribute to the results.

  12. Botanical prospecting for uranium on La Ventana Mesa, Sandoval County, New Mexico

    USGS Publications Warehouse

    Starrett, Wm. H.; Cannon, Helen L.

    1954-01-01

    A botanical sampling program has been completed by the U.S. Geological Survey on La Ventana Mesa, Sandoval County, N. Mex. A uranium-bearing coal in the Allison-Gibson members of the Cretaceous Mesaverde formation crops out in erosional remnants of the mesa.The coal is capped by a well-fractured 65-foot sandstone bed through which roots of a pinyon-juniper forest penetrate. Samples of several hundred branches of trees growing on top of the mesa were collected and analyzed for uranium. The assays ranged from 0.1 part per million to 2.3 ppm uranium in the wood ash. Dead branches, which were found to contain more uranium in the ash than live branches, were sampled where possible. The results have been contoured to indicated probable areas of mineralized coal. Parts of the north butte are recommended as favorable for physical exploration.

  13. Mountainous Ecosystem Sensor Array (MESA): a mesh sensor network for climate change research in remote mountainous environments

    NASA Astrophysics Data System (ADS)

    Robinson, P. W.; Neal, D.; Frome, D.; Kavanagh, K.; Davis, A.; Gessler, P. E.; Hess, H.; Holden, Z. A.; Link, T. E.; Newingham, B. A.; Smith, A. M.

    2013-12-01

    Developing sensor networks robust enough to perform unattended in the world's remote regions is critical since these regions serve as important benchmarks that lack anthropogenic influence. Paradoxically, the factors that make these remote, natural sites challenging for sensor networking are often what make them indispensable for climate change research. The MESA (Mountainous Ecosystem Sensor Array) project has faced these challenges and developed a wireless mesh sensor network across a 660 m topoclimatic gradient in a wilderness area in central Idaho. This sensor array uses advances in sensing, networking, and power supply technologies to provide near real-time synchronized data covering a suite of biophysical parameters used in ecosystem process models. The 76 sensors in the network monitor atmospheric carbon dioxide concentration, humidity, air and soil temperature, soil water content, precipitation, incoming and outgoing shortwave and longwave radiation, snow depth, wind speed and direction, and leaf wetness at synchronized time intervals ranging from two minutes to two hours and spatial scales from a few meters to two kilometers. We present our novel methods of placing sensors and network nodes above, below, and throughout the forest canopy without using meteorological towers. In addition, we explain our decision to use different forms of power (wind and solar) and the equipment we use to control and integrate power harvesting. Further, we describe our use of the network to sense and quantify its own power use. Using examples of environmental data from the project, we discuss how these data may be used to increase our understanding of the effects of climate change on ecosystem processes in mountainous environments. MESA sensor locations across a 700 m topoclimatic gradient at the University of Idaho Taylor Wilderness Research Station.

  14. 78 FR 26771 - Mesa Wind Power Corporation; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Mesa Wind Power Corporation; Supplemental Notice That Initial Market-Based... above-referenced proceeding of Mesa Wind Power Corporation's application for market-based rate...

  15. 75 FR 9219 - Notice of Intent To Prepare an Environmental Impact Statement for the Otay Mesa Land Port of Entry

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-01

    ... will modernize the existing Otay Mesa LPOE as mentioned in Alternative 1 and integrate long range... Newsletter distributed by the Otay Mesa Chamber of Commerce. All announced open house was held within the... house were made available in English and Spanish. The purpose of the open house was to...

  16. 75 FR 63488 - Submission for OMB Review; Comment Request; Multi-Ethnic Study of Atherosclerosis (MESA) Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... Study of Atherosclerosis (MESA) Event Surveillance SUMMARY: Under the provisions of Section 3507(a)(1)(D... Collection: Title: Multi-Ethnic Study of Atherosclerosis (MESA) Event Surveillance. Type of Information..., including the use of appropriate automated, electronic, mechanical, or other technological...

  17. 75 FR 76727 - Red Mesa Wind, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-09

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Red Mesa Wind, LLC; Supplemental Notice That Initial Market-Based Rate... notice in the above-referenced proceeding of Red Mesa Wind, LLC's application for market-based...

  18. Mesa Action Planning System: Results of a Survey of Community Residents on Future Trends, Challenges and Goals.

    ERIC Educational Resources Information Center

    Schrankel, Philipp Stephen; And Others

    The development of a planning model in the Mesa Unified School District (Arizona) to meet the need for a strategic planning process is examined. Surveys were mailed to 15,000 residents in the Mesa Public School District with a return of 1,933 surveys. Survey results indicate a prioritization of goals, an assessment of what the future may hold for…

  19. 75 FR 19422 - Notice of Closure of Airport Mesa/Carizzo Creek Shooting Area in Eastern San Diego County, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... Bureau of Land Management Notice of Closure of Airport Mesa/Carizzo Creek Shooting Area in Eastern San... as the Airport Mesa/Carrizo Creek shooting area located in eastern San Diego County, California. The closure order prohibits recreational shooting and target practice. The use of firearms will continue to...

  20. Bats of Mesa Verde National Park, Colorado: composition, reproduction, and roosting habits.

    USGS Publications Warehouse

    O'Shea, Thomas J.; Cryan, Paul M.; Snider, E. Apple; Valdez, Ernest W.; Ellison, Laura E.; Neubaum, Daniel J.

    2011-01-01

    We determined the bat fauna at Mesa Verde National Park (Mesa Verde) in 2006 and 2007, characterized bat elevational distribution and reproduction, and investigated roosting habits of selected species. We captured 1996 bats of 15 species in mist nets set over water during 120 nights of sampling and recorded echolocation calls of an additional species. The bat fauna at Mesa Verde included every species of bat known west of the Great Plains in Colorado, except the little brown bat (Myotis lucifugus). Some species showed skewed sex ratios, primarily due to a preponderance of males. Thirteen species of bats reproduced at Mesa Verde. Major differences in spring precipitation between the 2 years of our study were associated with differences in reproductive rates and, in some species, with numbers of juveniles captured. Reduced reproductive effort during spring drought will have a greater impact on bat populations with the forecasted increase in aridity in much of western North America by models of global climate change. We radiotracked 46 bats of 5 species to roosts and describe the first-known maternity colonies of spotted bats (Euderma maculatum) in Colorado. All 5 species that we tracked to diurnal roosts relied almost exclusively on rock crevices rather than trees or snags, despite the presence of mature forests at Mesa Verde and the use of trees for roosts in similar forests elsewhere by some of these species. Comparisons with past bat surveys at Mesa Verde and in surrounding areas suggest no dramatic evidence for effects of recent stand-replacing fires on the composition of the bat community.

  1. Management of dumping of packaged low-level wastes in the deep ocean with emphasis on the North East Atlantic dump site

    SciTech Connect

    Templeton, W.L.

    1981-08-01

    The following aspects are discussed: radiological principles as applied to disposal to the environment; international regulations; historical dumping practices; assessment of the Northeast Atlantic dump site; IAEA generic studies; and implications of issues on US needs and policies.

  2. Recording experiment on Rainier Mesa in conjunction with a reflection survey

    SciTech Connect

    Johnson, L.R.

    1994-06-01

    The chemical explosion of the NPE was recorded on the surface of Rainier Mesa along the same line which had previously been the site of a high resolution reflection survey. Six three-component accelerometer stations where distributed along the 550 meter line, which was offset about 600 meters from the epicenter of the explosion. The bandwidth of the acceleration data extends to 100 Hz. Even though the separations of the stations was only about 100 meters, the waveforms and the amplitudes exhibited considerable variability, especially for the transverse component of motion. The maximum accelerations ranged between 0.27 g and 1.46 g, with the maximums of the average traces being 0.57 g on the radial component, 0.28 on the transverse component, and 0.50 g on the vertical component. Using the results of the reflection survey to help constrain the velocity model, the acceleration data were inverted to obtain a preliminary estimate of the seismic moment tensor of the NPE. This result is a strong diagnostic for the NPE being an explosion, showing a somewhat asymmetric extensional source with very small shear components. When interpreted in terms of a spectral model and scaling relationships, the isotropic moment tensor indicates a yield of 1.4 kt, an elastic radius of 116 meters and a cavity radius of 15.5 meters. This interpretation includes a source time function which contains appreciable overshoot, and, if shown to be reliable, this feature of the explosion could have a significant effect upon the analyses of other types of seismic data.

  3. The Colorado MESA Program and CU-LASP: A Model for After School Program/Research Institution Collaboratives

    NASA Astrophysics Data System (ADS)

    Nelson, G.; Cobabe-Ammann, E.

    2004-12-01

    Colorado MESA is an after school program operating throughout the state with a long track record in promoting science, math and engineering education to largely underserved K-12 student populations. Currently, 81 percent of MESA students are from groups underrepresented in the math/science careers, and 85 percent of MESA students come from low- and moderate-income families. Through a combination of weekly student programs, field trips to universities and industry partners, family orientations, individual academic counseling and required curriculum, Colorado MESA offers an opportunity for students to explore STEM subjects and careers that they might not otherwise have access to - with tangible results. In the Colorado MESA Class of 2003, 97 percent of students planned on entering college this fall, with 86 percent indicating that they will enroll in math/science-based majors. In the last year, the University of Colorado's Laboratory for Atmospheric and Space Physics, a large space and earth sciences institute, has relied on the Colorado MESA program as its primary K-12 partner in Education and Public Outreach. LASP incorporates MESA into its proposal writing opportunities, from E/PO additions to individual research proposals to mission-level educational programs. In addition to funding opportunities, LASP provides scientists and engineers in a variety of contexts and content areas, while MESA works to incorporate those resources into their after school programs. The interface between the after school programs and the research institution requires ongoing communication and coordination in order to evaluate and fine-tune curriculum and activities based on feedback from MESA advisors and teachers. Currently, the MESA/LASP partnership has funded programs in astrobiology, planetary sciences and engineering.

  4. The Silent Canyon caldera: a three-dimensional model as part of a Pahute Mesa-Oasis Valley, Nevada, hydrogeologic model

    USGS Publications Warehouse

    McKee, Edwin H.; Phelps, Geoffery A.; Mankinen, Edward A.

    2001-01-01

    A 3-dimensional caldera model based on gravity inversion, drill-hole data, and geologic mapping offers the framework for a hydrogeologic evaluation of the Silent Canyon caldera in the central part of Pahute Mesa, Nevada. It has been recognized for several decades that the central part of Pahute Mesa is the site of a buried caldera called the Silent Canyon caldera. Conceptually, the structural framework of the Silent Canyon caldera is based on the idea of collapse of the caldera roof over a shallow magma chamber to form a structural basin following violent volcanic eruptions. Calderas are common in certain volcanic regions of the world, and most well-exposed calderas are broadly similar to each other, particularly the arcuate or circular shape of their collapse depression. There are other reasons for modeling the Silent Canyon caldera as a circular feature in addition to knowledge that calderas throughout the world are generally circular features. The Silent Canyon caldera is the site of one of the largest gravity lows in the Western United States, indicating a thick accumulation of low-density rocks such as lavas and tuffs—a fact confirmed by drilling on Pahute Mesa. This gravity low is bowl-shaped, and the uppermost volcanic units on Pahute Mesa form a circular outcrop pattern of inward-dipping tuff interpreted to be the result of their filling the upper part of the bowl-shaped depression. Together, these features are consistent with, and indicative of, a circular collapse structural model for the Silent Canyon caldera. The collapse depression of the Silent Canyon caldera, bounded by arcuate faults, is filled with as much as 6 km (19,800 ft) of volcanic and sedimentary rocks that are considerably less dense than the underlying and surrounding basement rocks. The boundary surface between less dense caldera fill and more dense basement is modeled as the caldera ring fault. Rocks in the upper part of the caldera fill are penetrated by drilling, and the drill-hole data are the basis for 3-dimensional computer modeling of the thickness and distribution of the rock units. The displacement on younger N-S faults that cut the caldera is also determined by offset of the computer derived surfaces defined by the drill-hole intercepts of stratigraphic units.

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

    NASA Technical Reports Server (NTRS)

    Burns, G. S.

    1983-01-01

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

  6. Site characterization summary report for dry weather surface water sampling upper East Fork Poplar Creek characterization area Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    1996-08-01

    This report describes activities associated with conducting dry weather surface water sampling of Upper East Fork Poplar Creek (UEFPC) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. This activity is a portion of the work to be performed at UEFPC Operable Unit (OU) 1 [now known as the UEFPC Characterization Area (CA)], as described in the RCRA Facility Investigation Plan for Group 4 at the Oak- Ridge Y-12 Plant, Oak Ridge, Tennessee and in the Response to Comments and Recommendations on RCRA Facility Investigation Plan for Group 4 at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, Volume 1, Operable Unit 1. Because these documents contained sensitive information, they were labeled as unclassified controlled nuclear information and as such are not readily available for public review. To address this issue the U.S. Department of Energy (DOE) published an unclassified, nonsensitive version of the initial plan, text and appendixes, of this Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) Plan in early 1994. These documents describe a program for collecting four rounds of wet weather and dry weather surface water samples and one round of sediment samples from UEFPC. They provide the strategy for the overall sample collection program including dry weather sampling, wet weather sampling, and sediment sampling. Figure 1.1 is a schematic flowchart of the overall sampling strategy and other associated activities. A Quality Assurance Project Plan (QAPJP) was prepared to specifically address four rounds of dry weather surface water sampling and one round of sediment sampling. For a variety of reasons, sediment sampling has not been conducted and has been deferred to the UEFPC CA Remedial Investigation (RI), as has wet weather sampling.

  7. 78 FR 18268 - Proposed Establishment of Class E Airspace; Blue Mesa, CO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ... ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034; February 26, 1979); and (3) does..., 40113, 40120; E.O. 10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p. 389. Sec. 71.1 0 2. The incorporation... Federal Aviation Administration 14 CFR Part 71 Proposed Establishment of Class E Airspace; Blue Mesa,...

  8. 78 FR 34554 - Establishment of Class E Airspace; Blue Mesa, CO

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-10

    ...) to establish controlled airspace at Blue Mesa, CO (78 FR 18268). Interested parties were invited to... Executive Order 12866; (2) is not a ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR...: Authority: 49 U.S.C. 106(g), 40103, 40113, 40120; E.O. 10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p....

  9. Kindergarten Entrance Age Requirements: Mesa Public Schools Research and Evaluation Tech Memo.

    ERIC Educational Resources Information Center

    Peterson, Sarah; Ayabe, Carol

    In the Mesa, Arizona, public schools, 4-year-old children with birthdays during the period from September to December were allowed to enter kindergarten if they passed the district screening test. Kindergarten teachers disagreed with this policy and recommended that, with no exceptions, the district no longer enroll 4-year-old children.…

  10. Mesa Verde: A Study of Man in an Agricultural Setting. Library Packet.

    ERIC Educational Resources Information Center

    Community Health Service (DHEW/PHS), Bethesda, MD.

    This collection of secondary readings contains general information about the ecology of living space, and specific information about the prehistory ecology of Mesa Verde, Colorado. There is also a section on how anthropologists use trees to date artifacts. A related document is indexed as ED 001 721. (AWW)

  11. Mesa Verde: A Study of Man in an Agricultural Setting. Student Manual.

    ERIC Educational Resources Information Center

    Community Health Service (DHEW/PHS), Bethesda, MD.

    This student manual contains information and guides to assist the secondary student in functioning as an archeologist. Included are fables, pictures for analysis, a time line and description of the pre-history of Mesa Verde, Colorado. The manual concludes with artifact identification word sheets. A related document is ED 001 722. (AWW)

  12. Women's Self-Efficacy Perceptions in Mathematics and Science: Investigating USC-MESA Students

    ERIC Educational Resources Information Center

    Hong, Rebecca C.; Jun, Alexander

    2012-01-01

    Higher education institutions have struggled with the underrepresentation of female students in the STEM majors. The authors investigate the USC-MESA program and the role of women's self-efficacy perceptions in mathematics and science. It is crucial to understand the theory of self-efficacy in examining historically underrepresented populations in…

  13. 77 FR 36531 - Yegua Mesa Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-19

    ... the Federal Power Act (FPA), proposing to continue studying the feasibility of the Yegua Mesa Pumped..., Symbiotics LLC, 811 SW Naito Parkway Ste. 120, Portland, Oregon 97204; phone: (503) 235-3424. FERC Contact: Carolyn Templeton; carolyn.templeton@ferc.gov ; phone: (202) 502-8785. Deadline for filing...

  14. Overview of the Multiscale Epidemiologic/Economic Simulation and Analysis (MESA) Decision Support System

    SciTech Connect

    Speck, D E

    2008-04-28

    The Multiscale Epidemiologic/Economic Simulation and Analysis (MESA) Decision Support System (DSS) is the product of investments that began in FY05 by the Department of Homeland Security (DHS) Science and Technology Directorate and continue today with joint funding by both DHS and the US Department of Agriculture (USDA). The DSS consists of a coupled epidemiologic/economic model, a standalone graphical user interface (GUI) that supports both model setup and post-analysis, and a Scenario Bank archive to store all content related to foreign animal disease (FAD) studies. The MESA epi model is an object-oriented, agent-based, stochastic, spatio-temporal simulator that parametrically models FAD outbreaks and response strategies from initial disease introduction to conclusion over local, regional, and national scales. Through its output database, the epi model couples to an economic model that calculates farm-level impacts from animal infections, responsive control strategies and loss of trade. The MESA architecture contains a variety of internal models that implement the major components of the epi simulation, including disease introduction, intra-herd spread, inter-herd spread (direct and indirect), detection, and various control strategies (movement restrictions, culling, vaccination) in a highly configurable and extensible fashion. MESA development was originally focused to support investigations into the economic and agricultural industry impacts associated with Foot-and-Mouth Disease (FMD outbreaks). However, it has been adapted to other FADs such has Highly Pathogenic Avian Influenza (HPAI), Classical Swine Fever (CSF) and Exotic Newcastle Disease (END). The MESA model is highly parameterized and employs an extensible architecture that permits straightforward addition of new component models (e.g., alternative disease spread approaches) when necessary. Since its inception, MESA has been developed with a requirement to enable simulation of the very large scale, nationwide disease outbreaks that are of special interest to DHS. MESA has been developed at Lawrence Livermore National Laboratory (LLNL) and has benefited from the world-class experience in supercomputing application development held by LLNL staff as well as the best-in-class high performance computing infrastructure in place at LLNL. MESA incorporates novel architectural features that permit it to make efficient use of available compute cycles by dynamically increasing the fidelity of the simulation in spatial (geopolitical) regions where relevant activity is occurring and keeping other regions aggregated into a computationally simpler representation. In addition to the MESA epi and economic models, the MESA DSS incorporates other key components. Integral to the parametric approach MESA employs to setup and define disease outbreak scenarios is a GUI that enables the MESA user to efficiently manage the thousands of parameters required by the simulator. The GUI provides individual parameter editors for groups of variables that support a common high level function, such as disease introduction, spread, control strategies, etc. It also provides a capability to browse through multiple study projects and develop n-additional outbreak scenarios per project through successive refinement of existing scenarios. Finally, the MESA GUI links post-processing applications that permit extraction of key data from MESA raw output, generation of spreadsheets, and geospatial mapping of simulation results. The MESA GUI is a standalone application that normally runs on the user's desktop, although its Java source code is portable and can execute under virtually any modern operating system. The final major component of the MESA DSS is the Scenario Bank, which is a web-served archive of unclassified FAD study content. The Scenario Bank implements a hierarchy of spaces, structured primarily along organizational lines (e.g., 'USDA', 'LLNL', etc), that permits participants to store simulator inputs, outputs, analysis results, reports, etc. and explicitly control who among Bank users may access them. Documents can be shared within organizations or across organizations at the owner's discretion. The Scenario Bank is intended to be the system of record for USDA and DHS sponsored FAD study efforts and as such will archive content from a variety of models employed by USDA and DHS-sponsored researchers and analysts.

  15. Sociodemographic correlates of cognition in the multi-ethnic study of atherosclerosis (MESA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to describe the methodology utilized to evaluate cognitive function in the Multi-Ethnic Study of Atherosclerosis (MESA) and to present preliminary results by age, sex, and race/ethnicity. Cross-sectional measurements of a prospective observational cohort. Residents of 6 U.S. commun...

  16. Error analysis for Mariner Venus/Mercury 1973 conducted at the JPL Mesa west antenna range

    NASA Technical Reports Server (NTRS)

    Vincent, N. L.; Smith, C. A.; Brejcha, A. J.; Curtis, H. A.

    1973-01-01

    Theoretical analysis and experimental data are combined to yield the errors to be used with antenna gain, antenna patterns, and RF cable insertion loss measurements for the Mariner Venus-Mercury 1973 Flight Project. These errors apply to measurements conducted at the JPL Mesa, West Antenna Range, on the high gain antenna, low gain antenna, and RF coaxial cables.

  17. GeoMesa: a distributed architecture for spatio-temporal fusion

    NASA Astrophysics Data System (ADS)

    Hughes, James N.; Annex, Andrew; Eichelberger, Christopher N.; Fox, Anthony; Hulbert, Andrew; Ronquest, Michael

    2015-05-01

    Recent advances in distributed databases and computing have transformed the landscape of spatio-temporal machine learning. This paper presents GeoMesa, a distributed spatio-temporal database built on top of Hadoop and column-family databases such as Accumulo and HBase, that includes a suite of tools for indexing, managing and analyzing both vector and raster data. The indexing techniques use space filling curves to map multi-dimensional data to the single lexicographic list managed by the underlying distributed database. In contrast to traditional non-distributed RDBMS, GeoMesa is capable of scaling horizontally by adding more resources at runtime; the index rebalances across the additional resources. In the raster domain, GeoMesa leverages Accumulo's server-side iterators and aggregators to perform raster interpolation and associative map algebra operations in parallel at query time. The paper concludes with two geo-time data fusion examples: using GeoMesa to aggregate Twitter data by keywords; and georegistration to drape full-motion video (FMV) over terrain.

  18. 78 FR 16816 - Radio Broadcasting Services; Ehrenberg, First Mesa, Kachina Village, Munds Park, Wickenburg, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-19

    ... Order to Show Cause, 77 FR 2241, published January 17, 2012. The full text of this Commission decision... COMMISSION 47 CFR Part 73 Radio Broadcasting Services; Ehrenberg, First Mesa, Kachina Village, Munds Park... filed by Univision Radio License Corporation for an increase in existing service by Station...

  19. Remedial action selection report Maybell, Colorado, site. Final report

    SciTech Connect

    1996-12-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The site is 2.5 mi (4 km) northeast of the Yampa River on relatively flat terrain broken by low, flat-topped mesas. U.S. Highway 40 runs east-west 2 mi (3.2 km) south of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. The site is situated between Johnson Wash to the east and Rob Pit Mine to the west. Numerous reclaimed and unreclaimed mines are in the immediate vicinity. Aerial photographs (included at the end of this executive summary) show evidence of mining activity around the Maybell site. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [ml]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd 3 (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd{sup 3}(420,000 m{sup 3}). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd{sup 3} (2.58 million m{sup 3}).

  20. East Arabia Landforms

    NASA Technical Reports Server (NTRS)

    2005-01-01

    11 November 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows two small mesas, a hill, and other landforms in the highly-eroded landscape of eastern Arabia Terra.

    Location near: 30.0oN, 295.0oW Image width: width: 3 km (1.9 mi) Illumination from: lower left Season: Northern Winter

  1. Completion Report for Well ER-16-1 Corrective Action Unit 99: Rainier Mesa - Shoshone Mountain

    SciTech Connect

    NSTec Geology Services

    2006-12-01

    Well ER-16-1 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. The well was drilled in June and July 2005 as part of a hydrogeologic investigation program for the Rainier Mesa-Shoshone Mountain Corrective Action Unit, Number 99. The overall purpose of the well was to gather subsurface data to better characterize the hydrogeology of the Shoshone Mountain area, especially in the older Tertiary and pre-Tertiary strata. The main 46.99-centimeter hole was drilled to a depth of 702.9 meters and cased with 33.97-centimeter casing to 663.7 meters. The hole diameter was then decreased to 31.1 centimeters, and the well was drilled to total depth of 1,220.7 meters. A completion string set at the depth of 1,162.4 meters consisted of 13.97-centimeter stainless-steel casing, with one continuous slotted interval open to the lower carbonate aquifer. The fluid level in the borehole soon dropped, so the borehole was deepened in July 2006. To deepen the borehole, the slotted section was cemented and a 12.1-centimeter hole was drilled through the bottom of the completion string to the new total depth of 1,391.7 meters, which is 171.0 meters deeper than the original borehole. A string of 6.03-centimeter carbon-steel tubing with one continuous slotted interval at 1,361.8 to 1,381.4 meters, and open to the lower carbonate aquifer, was installed in the well with no gravel packing or cement, to serve as a monitoring string. Data gathered during and shortly after hole construction include composite drill cuttings samples collected every 3 meters (extra cuttings samples were collected from the Paleozoic rocks for paleontological analyses), sidewall core samples from 37 depths, various geophysical logs, and water level measurements. These data indicate that the well penetrated 646.8 meters of Tertiary volcanic rocks and 744.9 meters of Paleozoic dolomite, quartzite, shale, and limestone. Three weeks after the monitoring string was installed, the water level was tagged at the drill hole depth of 1,271.9 meters, which equates to an estimated elevation of 761.7 meters, accounting for the borehole angle.

  2. Hunter-gatherer adaptations and environmental change in the southern Great Basin: The evidence from Pahute and Rainier mesas

    SciTech Connect

    Pippin, L.C.

    1998-06-01

    This paper reviews the evidence for fluctuations in past environments in the southern Great Basin and examines how these changes may have affected the strategies followed by past hunter and gatherers in their utilization of the resources available on a highland in this region. The evidence used to reconstruct past environments for the region include botanical remains from packrat middens, pollen spectra from lake and spring deposits, faunal remains recovered from archaeological and geologic contexts, tree-ring indices from trees located in sensitive (tree-line) environments, and eolian, alluvial and fluvial sediments deposited in a variety of contexts. Interpretations of past hunter and gatherer adaptive strategies are based on a sample of 1,311 archaeological sites recorded during preconstruction surveys on Pahute and Rainier mesas in advance of the US Department of Energy`s nuclear weapons testing program. Projectile point chronologies and available tree-ring, radiocarbon, thermoluminescence and obsidian hydration dates were used to assign these archaeological sites to specific periods of use.

  3. 4. East elevation, facing west (Note: B/W scale on east ...

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

    4. East elevation, facing west (Note: B/W scale on east elevation in 1/2 ft increments) - Nevada Test Site, Reactor Maintenance & Disassembly Complex, Junior Hot Cell, Jackass Flats, Area 25, South of intersection of Roads F & G, Mercury, Nye County, NV

  4. Phytoremediation of Pb, Zn, Fe, and Mg with 25 wetland plant species from a paper mill contaminated site in North East India.

    PubMed

    Mazumdar, Kisholay; Das, Suchismita

    2015-01-01

    In order to assess the potential of wetland plants to remediate metals from a paper mill effluent contaminated wetland site in Northeast India, 25 abundant plant species belonging to 15 different families, soil, and water samples from the sites were tested for Pb, Zn, Mg, and Fe by atomic absorption spectrophotometer. The results showed that metal accumulation by wetland plants differed among species and tissues. Plants thrived in high Pb, Zn, Mg, and Fe which indicated their tolerance. According to the criteria used for selecting plants for phytoremediation such as high metal tolerance, short life cycle, wide distribution, large shoot biomass and translocation factor (TF) >1; five species each were Mg and Fe accumulators, nine species were Pb accumulators and, eight species were Zn accumulators and the rest were excluders. Alternanthera sessilis was the only plant species that had TF > 1 for all the four metals. The study indicated great promise for phytoremediation, as these accumulators could be used in future for practical phytoremediation approaches and reduction of the risk from harmful metals to human health. PMID:25103945

  5. Atmospheric mercury concentrations at two sites in the Kyushu Islands, Japan, and evidence of long-range transport from East Asia

    NASA Astrophysics Data System (ADS)

    Marumoto, Kohji; Hayashi, Masahiko; Takami, Akinori

    2015-09-01

    Continuous monitoring of atmospheric gaseous mercury at Fukuoka and Minamata in the Kyushu Islands, western Japan, was carried out from June 2012 to May 2013 to investigate the influence of long-range transport of mercury in the Asian region. Speciation data at Fukuoka indicated that approximately 99% of the atmospheric mercury was in the gaseous elemental form. The average concentration of gaseous elemental mercury (GEM) at Fukuoka was slightly higher than that of total gaseous mercury (TGM) at Minamata. Synchronous pollution events of higher concentrations of both GEM at Fukuoka and TGM at Minamata were frequently observed from late fall to early spring. We infer that these events occurred due to long-range transport of mercury rather than local, domestic emission sources because the two sites are far apart (about 150 km), and local sources would be unlikely to synchronously influence concentrations at both sites over such a long distance. The results of backward trajectory analyses indicated that these events occurred when air masses came from the Asian continent. In addition, the pollution events were often the result of cold fronts or migratory anticyclones that passed over the Kyushu Islands, often accompanied by descending cool and heavy air currents. Thus, these results indicate that, under specific climate conditions, higher concentrations of atmospheric mercury are transported to the Kyushu Islands from the Asian continent, and are evident in ground-based observations there.

  6. Year-round records of sea salt, gaseous, and particulate inorganic bromine in the atmospheric boundary layer at coastal (Dumont d'Urville) and central (Concordia) East Antarctic sites

    NASA Astrophysics Data System (ADS)

    Legrand, Michel; Yang, Xin; Preunkert, Susanne; Theys, Nicolas

    2016-01-01

    Multiple year-round records of bulk and size-segregated compositions of aerosol were obtained at the coastal Dumont d'Urville (DDU) and inland Concordia sites located in East Antarctica. They document the sea-salt aerosol load and composition including, for the first time in Antarctica, the bromide depletion of sea-salt aerosol relative to sodium with respect to seawater. In parallel, measurements of bromide trapped in mist chambers and denuder tubes were done to investigate the concentrations of gaseous inorganic bromine species. These data are compared to simulations done with an off-line chemistry transport model, coupled with a full tropospheric bromine chemistry scheme and a process-based sea-salt production module that includes both sea-ice-sourced and open-ocean-sourced aerosol emissions. Observed and simulated sea-salt concentrations sometime differ by up to a factor of 2 to 3, particularly at DDU possibly due to local wind pattern. In spite of these discrepancies, both at coastal and inland Antarctica, the dominance of sea-ice-related processes with respect to open ocean emissions for the sea-salt aerosol load in winter is confirmed. For summer, observations and simulations point out sea salt as the main source of gaseous inorganic bromine species. Investigations of bromide in snow pit samples do not support the importance of snowpack bromine emissions over the Antarctic Plateau. To evaluate the overall importance of the bromine chemistry over East Antarctica, BrO simulations were also discussed with respect data derived from GOME-2 satellite observations over Antarctica.

  7. Completion Report for Well ER-20-7: Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Restoration

    2010-04-28

    Well ER-20-7 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Nevada Environmental Restoration Project at the Nevada Test Site, Nye County, Nevada. The well was drilled in June 2009 as part of the Pahute Mesa Phase II drilling program. The primary purpose of the well was to further investigate migration of radionuclides from the nearby, up-gradient TYBO and BENHAM underground nuclear tests, which originally was discovered at Well Cluster ER-20-5. This well also provided detailed hydrogeologic information in the Tertiary volcanic section that will reduce uncertainties within the Pahute Mesa-Oasis Valley hydrostratigraphic framework model. The main 44.45-centimeter hole was drilled to a depth of 681.8 meters and cased with 33.97-centimeter casing to 671.7 meters. The hole diameter was then decreased to 31.12 centimeters, and the well was drilled to total depth of 894.9 meters. The completion string, set to the depth of 890.0 meters, consists of 14.13-centimeter stainless-steel casing hanging from 19.37-centimeter carbon-steel casing. The 14.13-centimeter stainless-steel casing has one continuous slotted interval open to the Topopah Spring aquifer. Data collected during and shortly after hole construction include composite drill cuttings samples collected every 3.0 meters, sidewall core samples from 20 depth intervals, various geophysical logs, water quality (primarily tritium) measurements, and water level measurements. The well penetrated 894.9 meters of Tertiary volcanic rock, including two saturated welded-tuff aquifers. A fluid level measurement was obtained during open-hole geophysical well logging for the upper, Tiva Canyon, aquifer at the depth of 615.7 meters on June 19, 2009. The fluid level measured in the open hole on June 27, 2009,after the total depth was reached and the upper aquifer was cased off, was also at the depth of 615.7 meters. Preliminary field measurements indicated 1.5 to 4.5 million picocuries per liter of tritium in the Tiva Canyon aquifer and 20 to 61 million picocuries per liter in the underlying Topopah Spring aquifer.

  8. Pollen and Phytolith Evidence for Rice Cultivation and Vegetation Change during the Mid-Late Holocene at the Jiangli Site, Suzhou, East China

    PubMed Central

    Qiu, Zhenwei; Jiang, Hongen; Ding, Jinlong; Hu, Yaowu; Shang, Xue

    2014-01-01

    Pollen and phytolith analyses were undertaken at the Jiangli site in Suzhou, Jiangsu Province, combined with studies on macrofossils by flotation. The concentration of pollen decreased while the percentage of Poaceae pollen in the profile increased from the late phase of the Majiabang Culture to the Songze Culture suggesting that human impact on the local environment intensified gradually. The discovery of rice paddy implies a relatively advanced rice cultivation in this area during the middle-late Holocene. Other than phytoliths, the high percentage of Oryza-type Poaceae pollen (larger than 40 µm) supplied robust evidence for the existence of rice paddy. Moreover, the fact that the farther from the rice paddy, the lower the concentration and percentage of Poaceae pollen also proves that the dispersal and deposition of pollen is inversely proportional to the distance. PMID:24466254

  9. Pollen and phytolith evidence for rice cultivation and vegetation change during the mid-late Holocene at the Jiangli site, Suzhou, East China.

    PubMed

    Qiu, Zhenwei; Jiang, Hongen; Ding, Jinlong; Hu, Yaowu; Shang, Xue

    2014-01-01

    Pollen and phytolith analyses were undertaken at the Jiangli site in Suzhou, Jiangsu Province, combined with studies on macrofossils by flotation. The concentration of pollen decreased while the percentage of Poaceae pollen in the profile increased from the late phase of the Majiabang Culture to the Songze Culture suggesting that human impact on the local environment intensified gradually. The discovery of rice paddy implies a relatively advanced rice cultivation in this area during the middle-late Holocene. Other than phytoliths, the high percentage of Oryza-type Poaceae pollen (larger than 40 μm) supplied robust evidence for the existence of rice paddy. Moreover, the fact that the farther from the rice paddy, the lower the concentration and percentage of Poaceae pollen also proves that the dispersal and deposition of pollen is inversely proportional to the distance. PMID:24801163

  10. Pollen and phytolith evidence for rice cultivation and vegetation change during the mid-late holocene at the Jiangli site, Suzhou, East China.

    PubMed

    Qiu, Zhenwei; Jiang, Hongen; Ding, Jinlong; Hu, Yaowu; Shang, Xue

    2014-01-01

    Pollen and phytolith analyses were undertaken at the Jiangli site in Suzhou, Jiangsu Province, combined with studies on macrofossils by flotation. The concentration of pollen decreased while the percentage of Poaceae pollen in the profile increased from the late phase of the Majiabang Culture to the Songze Culture suggesting that human impact on the local environment intensified gradually. The discovery of rice paddy implies a relatively advanced rice cultivation in this area during the middle-late Holocene. Other than phytoliths, the high percentage of Oryza-type Poaceae pollen (larger than 40 µm) supplied robust evidence for the existence of rice paddy. Moreover, the fact that the farther from the rice paddy, the lower the concentration and percentage of Poaceae pollen also proves that the dispersal and deposition of pollen is inversely proportional to the distance. PMID:24466254

  11. Hygroscopic behavior of water-soluble matter extracted from biomass burning aerosols collected at a rural site in Tanzania, East Africa

    NASA Astrophysics Data System (ADS)

    Boreddy, S. K. R.; Kawamura, Kimitaka; Mkoma, Stelyus; Fu, Pingqing

    2014-11-01

    In this study, we present the hygroscopic behavior of water-soluble matter (WSM) extracted from biomass burning derived particulate matter 2.5 (PM2.5) aerosols collected at a rural background site in Tanzania during June-August 2011. Hygroscopic growth factors, g(RH), of WSM were measured by hygroscopic tandem differential mobility analyzer (H-TDMA) with an initial dry particle diameter of 100 nm. We observed that the g(RH) of WSM at 90% relative humidity (RH), g(90%)WSM, ranged from 1.10 to 1.47 with an average of 1.25 ± 0.12. The H-TDMA retrieved hygroscopicity parameter of WSM, κWSM, ranged from 0.04 to 0.24 with a mean of 0.11 ± 0.07. We found that the observed g(90%)WSM is positively correlated with PM2.5 mass fractions of K+ (R2 = 0.61), Cl- (0.54), and organic carbon (0.58). Moreover, it well correlates with levoglucosan (0.67) and total diacids (0.76), implying that although the inorganic fraction may be the most important factor to control the hygroscopicity; biomass burning organics play a significant role in the hygroscopicity of Tanzanian aerosols. The lower growth factors obtained over the sampling site are probably due to the formation of less water-soluble potassium oxalate (K2C2O4) or less hygroscopic K2SO4 particles during atmospheric aging. We observed a moderate correlation (R2 = 0.33) between PM2.5 mass fraction of WSOC and g(90%)WSM. The retrieved g(90%)WSOM values ranged from 1.0 to 1.25 with a mean of 1.16 ± 0.05. This study demonstrates that the hygroscopicity of Tanzanian aerosols is largely controlled by the emission of biomass burning products and the subsequent chemical aging during atmospheric transport.

  12. Calcified coronary artery plaque measurement with cardiac CT in population-based studies: standardized protocol of Multi-Ethnic Study of Atherosclerosis (MESA) and Coronary Artery Risk Development in Young Adults (CARDIA) study.

    PubMed

    Carr, J Jeffrey; Nelson, Jennifer Clark; Wong, Nathan D; McNitt-Gray, Michael; Arad, Yadon; Jacobs, David R; Sidney, Stephan; Bild, Diane E; Williams, O Dale; Detrano, Robert C

    2005-01-01

    Calcified coronary artery plaque, measured at cardiac computed tomography (CT), is a predictor of cardiovascular disease and may play an increasing role in cardiovascular disease risk assessment. The Multi-Ethnic Study of Atherosclerosis (MESA) and the Coronary Artery Risk Development in Young Adults (CARDIA) study of the National Heart, Lung, and Blood Institute are population-based studies in which calcified coronary artery plaque was measured with electron-beam and multi-detector row CT and a standardized protocol in 6814 (MESA) and 3044 (CARDIA study) participants. The studies were approved by the appropriate institutional review board from the study site or agency, and written informed consent was obtained from each participant. Participation in the CT examination was high, image quality was good, and agreement for the presence of calcified plaque was high (kappa = 0.92, MESA; kappa = 0.77, CARDIA study). Extremely high agreement was observed between and within CT image analysts for the presence (kappa > 0.90, all) and amount (intraclass correlation coefficients, >0.99) of calcified plaque. Measurement of calcified coronary artery plaque with cardiac CT is well accepted by participants and can be implemented with consistently high-quality results with a standardized protocol and trained personnel. If predictive value of calcified coronary artery plaque for cardiovascular events proves sufficient to justify screening a segment of the population, then a standardized cardiac CT protocol is feasible and will provide reproducible results for health care providers and the public. PMID:15618373

  13. Geological site characterization for the proposed Mixed Waste Disposal Facility, Los Alamos National Laboratory

    SciTech Connect

    Reneau, S.L.; Raymond, R. Jr.

    1995-12-01

    This report presents the results of geological site characterization studies conducted from 1992 to 1994 on Pajarito Mesa for a proposed Los Alamos National Laboratory Mixed Waste Disposal Facility (MWDF). The MWDF is being designed to receive mixed waste (waste containing both hazardous and radioactive components) generated during Environmental Restoration Project cleanup activities at Los Alamos. As of 1995, there is no Resource Conservation and Recovery Act (RCRA) permitted disposal site for mixed waste at the Laboratory, and construction of the MWDF would provide an alternative to transport of this material to an off-site location. A 2.5 km long part of Pajarito Mesa was originally considered for the MWDF, extending from an elevation of about 2150 to 2225 m (7060 to 7300 ft) in Technical Areas (TAs) 15, 36, and 67 in the central part of the Laboratory, and planning was later concentrated on the western area in TA-67. The mesa top lies about 60 to 75 m (200 to 250 ft) above the floor of Pajarito Canyon on the north, and about 30 m (100 ft) above the floor of Threemile Canyon on the south. The main aquifer used as a water supply for the Laboratory and for Los Alamos County lies at an estimated depth of about 335 m (1100 ft) below the mesa. The chapters of this report focus on surface and near-surface geological studies that provide a basic framework for siting of the MWDF and for conducting future performance assessments, including fulfillment of specific regulatory requirements. This work includes detailed studies of the stratigraphy, mineralogy, and chemistry of the bedrock at Pajarito Mesa by Broxton and others, studies of the geological structure and of mesa-top soils and surficial deposits by Reneau and others, geologic mapping and studies of fracture characteristics by Vaniman and Chipera, and studies of potential landsliding and rockfall along the mesa-edge by Reneau.

  14. Racial/Ethnic Differences in Sleep Disturbances: The Multi-Ethnic Study of Atherosclerosis (MESA)

    PubMed Central

    Chen, Xiaoli; Wang, Rui; Zee, Phyllis; Lutsey, Pamela L.; Javaheri, Sogol; Alcntara, Carmela; Jackson, Chandra L.; Williams, Michelle A.; Redline, Susan

    2015-01-01

    Objectives: There is limited research on racial/ethnic variation in sleep disturbances. This study aimed to quantify the distributions of objectively measured sleep disordered breathing (SDB), short sleep duration, poor sleep quality, and self-reported sleep disturbances (e.g., insomnia) across racial/ethnic groups. Design: Cross-sectional study. Setting: Six US communities. Participants: Racially/ethnically diverse men and women aged 5493 y in the Multi-Ethnic Study of Atherosclerosis Sleep Cohort (n = 2,230). Interventions: N/A. Measurements and Results: Information from polysomnography-measured SDB, actigraphy-measured sleep duration and quality, and self-reported daytime sleepiness were obtained between 2010 and 2013. Overall, 15.0% of individuals had severe SDB (apnea-hypopnea index [AHI] ? 30); 30.9% short sleep duration (< 6 h); 6.5% poor sleep quality (sleep efficiency < 85%); and 13.9% had daytime sleepiness. Compared with Whites, Blacks had higher odds of sleep apnea syndrome (AHI ? 5 plus sleepiness) (sex-, age-, and study site-adjusted odds ratio [OR] = 1.78, 95% confidence interval [CI]: 1.20, 2.63), short sleep (OR = 4.95, 95% CI: 3.56, 6.90), poor sleep quality (OR = 1.57, 95% CI: 1.00, 2.48), and daytime sleepiness (OR = 1.89, 95% CI: 1.38, 2.60). Hispanics and Chinese had higher odds of SDB and short sleep than Whites. Among non-obese individuals, Chinese had the highest odds of SDB compared to Whites. Only 7.4% to 16.2% of individuals with an AHI ? 15 reported a prior diagnosis of sleep apnea. Conclusions: Sleep disturbances are prevalent among middle-aged and older adults, and vary by race/ethnicity, sex, and obesity status. The high prevalence of sleep disturbances and undiagnosed sleep apnea among racial/ethnic minorities may contribute to health disparities. Citation: Chen X, Wang R, Zee P, Lutsey PL, Javaheri S, Alcntara C, Jackson CL, Williams MA, Redline S. Racial/ethnic differences in sleep disturbances: the Multi-Ethnic Study of Atherosclerosis (MESA). SLEEP 2015;38(6):877888. PMID:25409106

  15. Analysis of Well ER-EC-5 Testing, Western Pahute Mesa-Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-5 during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-EC-5 Data Report for Development and Hydraulic Testing.

  16. Analysis of Well ER-EC-1 Testing, Western Pahute Mesa-Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-1 during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-EC-1 Data Report for Development and Hydraulic Testing.

  17. Analysis of Well ER-EC-7 Testing, Western Pahute Mesa - Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-7 during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program was documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-EC-7 Data Report for Development and Hydraulic Testing.

  18. Analysis of Well ER-EC-8 testing, Western Pahute Mesa-Oasis Valley FY 2000 testing program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-8 during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa-Oasis Valley, Well ER-EC-8 Data Report for development and Hydraulic Testing.

  19. Analysis of Well ER-EC-6 Testing, Western Pahute Mesa - Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-6 during the Western Pahute Mesa-Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa-Oasis Valley, Well ER-EC-6 Data Report for Development and Hydraulic Testing.

  20. Analysis of Well ER-EC-4 Testing, Western Pahute Mesa-Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-4 during the Western Pahute Mesa-Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-EC-4 Data Report for Development and Hydraulic Testing.

  1. Analysis of well ER-18-2 testing, Western Pahute Mesa - Oasis Valley FY 2000 testing program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-18-2 during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-18-2 Data Report for Development and Hydraulic Testing.

  2. Analysis of Well ER-EC-2a Testing, Western Pahute Mesa-Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report documents the analysis of the data collected for Well ER-EC-2a during the Western Pahute Mesa - Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. The data collection for that program is documented in Appendix A, Western Pahute Mesa - Oasis Valley, Well ER-EC-2a Data Report for Development and Hydraulic Testing.

  3. Seasonal variations of stable carbon isotopic composition of bulk aerosol carbon from Gosan site, Jeju Island in the East China Sea

    NASA Astrophysics Data System (ADS)

    Kundu, Shuvashish; Kawamura, Kimitaka

    2014-09-01

    This study explores the usefulness of stable isotopic composition (δ13C) along with other chemical tracers and air mass trajectory to identify the primary and secondary sources of carbonaceous aerosols. Aerosol samples (n = 84) were collected continuously from April 2003 to April 2004 at Gosan site in Jeju Island, South Korea. The concentrations of total carbon (TC), HCl fumed carbonate-free total carbon (fumed-TC) and their δ13C were measured online using elemental analyzer interfaced to isotope ratio mass spectrometer (EA-IRMS). Similar concentrations of TC and fumed-TC and their similar δ13C values suggest the insignificant contribution of inorganic carbon to Gosan aerosols. The monthly averaged δ13CTC showed the lowest in April/May (-24.2 to -24.4‰), which is related with the highest concentrations of oxalic acid (a secondary tracer). The result indicates an enhanced contribution of TC from secondary sources. The monthly averaged δ13CTC in July/August (-23.0 to -22.5‰) were similar to those in January/February (-23.1‰ to -22.7‰). However, chemical tracers and air mass transport pattern suggest that the pollution source regions in January/February are completely different from those in July/August. Higher δ13C values in July/August are aligned with higher concentration ratios of marine tracers (azelaic acid/TC and methanesulfonate/TC), suggesting an enhanced contribution of marine organic matter to the aerosol loading. Higher δ13C values in January/February are associated with higher concentrations of phthalic acid and K+/TC, indicating more contributions of carbonaceous aerosols from fossil fuel and C4-plant biomass combustion. This study demonstrates that δ13CTC, along with other chemical tracers and air mass trajectory, can be used as a tracer to understand the importance of primary versus secondary pollution sources of carbonaceous aerosols in the atmosphere.

  4. Final design, installation and baseline testing of 500 kW direct contact pilot plant at East Mesa

    SciTech Connect

    Hlinak, A.; Lobach, J.; Nichols, K.; Olander, R.; Werner, D.

    1980-05-30

    The pilot plant was configured to accomplish two objectives - first to evaluate the overall performance potential of direct contact powerplants and second to develop design criteria and parameters for full-scale direct contact plants. The pilot plant includes all of the process functions that would be incorporated in a full-scale plant. Incoming brine is treated to remove undissolved gases, pumped through the direct contact heat exchanger (DCHX), and then sent to a recovery system for removal of the dissolved working fluid. The chosen working fluid is isobutane (IC/sub 4/). The working fluid loop includes a radial inflow turbine with generator, condensers, hot-well reservoir, and a feed pump. A downwell pump was installed in the geothermal well to supply the plant with unflashed brine. (MHR)

  5. Final phase testing and evaluation of the 500 kW direct contact pilot plant at East Mesa

    SciTech Connect

    Olander, R.; Oshmyansky, S.; Nichols, K.; Werner, D.

    1983-12-01

    The testing performed during the last phase of the geothermal direct contact heat exchanger program utilizing the 500 kW pilot plant provided more insight into the capabilities and limits of the direct contact approach and showed that more work needs to be done to understand the inner workings of a large direct contact heat exchanger if they are to be modeled analytically. Testing of the column demonstrated that the performance was excellent and that the sizing criteria is conservative. The system operated smoothly and was readily controlled over a wide range of operating conditions. Performance evaluation showed pinch differentials of 4/sup 0/F or less and better than predicted heat transfer capability. Testing during this final phase was directed towards establishing the limits of the column to transfer heat. The working column height was shortened progressively to approximately 16 feet from a design length of 28 feet. The short column performed as well as a full length column and there are indications that the column could have been shortened even more without affecting its ability to transfer heat. The column's ability to perform as well with shortened lengths indicates that the heat transfer coefficients and criteria derived from the small scale tests are very conservative.

  6. Geologic effects of the Greeley event, Nevada Test site

    USGS Publications Warehouse

    Dickey, Dayton Delbert; Jenkins, E.C.; McKeown, F.A.; Lee, W.H.

    1969-01-01

    The intermediate yield Greeley event, in which a nuclear device was detonated at a depth of 3,990 feet in Pahute Mesa at the Nevada Test Site, caused fracturing in rocks and spalling of rock from cliffs as far as 3 and 8 miles, respectively, from the detonation point.

  7. Differential Sensitivity Theory applied to the MESA code for high pressure interactions

    NASA Astrophysics Data System (ADS)

    Maudlin, P. J.; Henninger, R. J.; Harstad, E. N.

    A technique called Differential Sensitivity Theory (DST) is applied to the system of equations solved by the MESA hydrocode. DST uses adjoint techniques to determine exact sensitivity derivatives, i.e., if R is a calculational result of interest (response R) and alpha(sub i) is a calculational input (parameter alpha(sub i)), then (partial derivative)R/(partial derivative)alpha(sub i) is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem all n sensitivities can be obtained by integrating the solutions from only two calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics code (ACM). This work describes the derivation and solution of the appropriate set of adjoint and sensitivity equations for the purpose of computing sensitivities for high-rate two-dimensional, multi-component, high deformation problems. As an example, results are presented for a flyer plate problem.

  8. Differential Sensitivity Theory applied to the MESA code for high pressure interactions

    SciTech Connect

    Maudlin, P.J.; Henninger, R.J.; Harstad, E.N.

    1993-07-01

    A technique called Differential Sensitivity Theory (DST) is applied to the system of equations solved by the MESA hydrocode. DST uses adjoint techniques to determine exact sensitivity derivatives, i.e., if R is a calculational result of interest (response R) and {alpha}{sub i} is a calculational input (parameter {alpha}{sub i}), then {partial_derivative}R/{partial_derivative}{alpha}{sub i} is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem all n sensitivities can be obtained by integrating the solutions from only two calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics code (ACM). This work describes the derivation and solution of the appropriate set of adjoint and sensitivity equations for the purpose of computing sensitivities for high-rate two-dimensional, multi-component, high deformation problems. As an example, results are presented for a flyer plate problem.

  9. MESA 3-D calculations of armor penetration by projectiles with combined obliquity and yaw

    SciTech Connect

    Cagliostro, D.J.; Mandell, D.A.; Schwalbe, L.A.; Adams, T.F.; Chapyak, E.J. )

    1989-01-01

    We introduce and briefly describe MESA, a new 3-D hydrodynamic code, developed specifically for simulations of armor and anti-armor systems. The code's current capabilities an its planned model improvements and additions are discussed. An Eulerian code using state-of-the-art numerical methods, MESA runs faster and is less affected by spurious numerical diffusion than older codes. It models hydrodynamic flow and the dynamic deformation of solid materials. It uses simple elastic-perfectly plastic material strength models as well as models with strain and strainrate hardening and thermal softening. Future versions will incorporate advanced fracture models. It treats detonations in explosives using a programmed burn. The code's current capabilities are illustrated with simulations of experiments on yawed rods obliquely impacting armor plates at 1.29 km/s. 12 refs., 14 figs.

  10. Air Pollution and Individual and Neighborhood Socioeconomic Status: Evidence from the Multi-Ethnic Study of Atherosclerosis (MESA)

    PubMed Central

    Diez-Roux, Ana V.; Adar, Sara D.; Auchincloss, Amy H.; Lovasi, Gina S.; O’Neill, Marie S.; Sheppard, Lianne; Kaufman, Joel D.

    2013-01-01

    Background: Although research has shown that low socioeconomic status (SES) and minority communities have higher exposure to air pollution, few studies have simultaneously investigated the associations of individual and neighborhood SES with pollutants across multiple sites. Objectives: We characterized the distribution of ambient air pollution by both individual and neighborhood SES using spatial regression methods. Methods: The study population comprised 6,140 participants from the Multi-Ethnic Study of Atherosclerosis (MESA). Year 2000 annual average ambient PM2.5 and NOx concentrations were calculated for each study participant’s home address at baseline examination. We investigated individual and neighborhood (2000 U.S. Census tract level) SES measures corresponding to the domains of income, wealth, education, and occupation. We used a spatial intrinsic conditional autoregressive model for multivariable analysis and examined pooled and metropolitan area–specific models. Results: A 1-unit increase in the z-score for family income was associated with 0.03-μg/m3 lower PM2.5 (95% CI: –0.05, –0.01) and 0.93% lower NOx (95% CI: –1.33, –0.53) after adjustment for covariates. A 1-SD–unit increase in the neighborhood’s percentage of persons with at least a high school degree was associated with 0.47-μg/m3 lower mean PM2.5 (95% CI: –0.55, –0.40) and 9.61% lower NOx (95% CI: –10.85, –8.37). Metropolitan area–specific results exhibited considerable heterogeneity. For example, in New York, high-SES neighborhoods were associated with higher concentrations of pollution. Conclusions: We found statistically significant associations of SES measures with predicted air pollutant concentrations, demonstrating the importance of accounting for neighborhood- and individual-level SES in air pollution health effects research. Citation: Hajat A, Diez-Roux AV, Adar SD, Auchincloss AH, Lovasi GS, O’Neill MS, Sheppard L, Kaufman JD. 2013. Air pollution and individual and neighborhood socioeconomic status: evidence from the Multi-Ethnic Study of Atherosclerosis (MESA). Environ Health Perspect 121:1325–1333; http://dx.doi.org/10.1289/ehp.1206337 PMID:24076625

  11. Evaluation of Pleistocene groundwater flow through fractured tuffs using a U-series disequilibrium approach, Pahute Mesa, Nevada, USA

    USGS Publications Warehouse

    Paces, James B.; Nichols, Paul J.; Neymark, Leonid A.; Rajaram, Harihar

    2013-01-01

    Groundwater flow through fractured felsic tuffs and lavas at the Nevada National Security Site represents the most likely mechanism for transport of radionuclides away from underground nuclear tests at Pahute Mesa. To help evaluate fracture flow and matrix–water exchange, we have determined U-series isotopic compositions on more than 40 drill core samples from 5 boreholes that represent discrete fracture surfaces, breccia zones, and interiors of unfractured core. The U-series approach relies on the disruption of radioactive secular equilibrium between isotopes in the uranium-series decay chain due to preferential mobilization of 234U relative to 238U, and U relative to Th. Samples from discrete fractures were obtained by milling fracture surfaces containing thin secondary mineral coatings of clays, silica, Fe–Mn oxyhydroxides, and zeolite. Intact core interiors and breccia fragments were sampled in bulk. In addition, profiles of rock matrix extending 15 to 44 mm away from several fractures that show evidence of recent flow were analyzed to investigate the extent of fracture/matrix water exchange. Samples of rock matrix have 234U/238U and 230Th/238U activity ratios (AR) closest to radioactive secular equilibrium indicating only small amounts of groundwater penetrated unfractured matrix. Greater U mobility was observed in welded-tuff matrix with elevated porosity and in zeolitized bedded tuff. Samples of brecciated core were also in secular equilibrium implying a lack of long-range hydraulic connectivity in these cases. Samples of discrete fracture surfaces typically, but not always, were in radioactive disequilibrium. Many fractures had isotopic compositions plotting near the 230Th-234U 1:1 line indicating a steady-state balance between U input and removal along with radioactive decay. Numerical simulations of U-series isotope evolution indicate that 0.5 to 1 million years are required to reach steady-state compositions. Once attained, disequilibrium 234U/238U and 230Th/238U AR values can be maintained indefinitely as long as hydrological and geochemical processes remain stable. Therefore, many Pahute Mesa fractures represent stable hydrologic pathways over million-year timescales. A smaller number of samples have non-steady-state compositions indicating transient conditions in the last several hundred thousand years. In these cases, U mobility is dominated by overall gains rather than losses of U.

  12. Counterclockwise rotations in the Late Eocene-Oligocene volcanic fields of San Luis Potosí and Sierra de Guanajuato (eastern Mesa Central, Mexico)

    NASA Astrophysics Data System (ADS)

    Andreani, Louis; Gattacceca, Jerôme; Rangin, Claude; Martínez-Reyes, Juventino; Demory, François

    2014-12-01

    We used paleomagnetic and structural data to investigate the late Eocene-Oligocene tectonic evolution of the Mesa Central area in Mexico. The Mesa Central was affected by NW-trending faults (Tepehuanes-San Luis fault system) coeval with a Late Eocene-Oligocene ignimbrite flare-up and by post-27 Ma NNE-trending grabens related to the Basin and Range. We obtained reliable paleomagnetic directions from 61 sites within the Late Eocene-Oligocene volcanic series (~ 30 to ~ 27 Ma) of the San Luis Potosí volcanic field and Sierra de Guanajuato. For each site we also measured the anisotropy of magnetic susceptibility (AMS). Tilt corrections were made using AMS data for 33 sites where in situ bedding measurements were not available. Paleomagnetic directions indicate counterclockwise rotations of about 10° with respect to stable North America after 30-25 Ma. Structural data suggest that the volcanic succession was mainly affected by normal faults. However, we also found evidences for oblique or horizontal striae showing a left-lateral component along NW-trending faults and a right lateral component along NE-trending faults. Both motions are consistent with a N-S extension oblique to the Tepehuanes-San Luis fault system. Previous paleomagnetic studies in northern and southern Mexico show the prevalence of minor left-lateral shear components along regional-scale transpressional and transtensional lineaments. Our paleomagnetic data may reflect thus small vertical-axis rotations related to a minor shear component coeval with the Oligocene intra-arc extension in central Mexico.

  13. Mineral resources of the Dominguez Canyon Wilderness Study Area, Delta, Mesa, and Montrose counties, Colorado

    SciTech Connect

    Toth, M.I.; Patterson, C.G.; Kulik, D.M.; Schreiner, R.A.

    1987-01-01

    The Dominguez Canyon Wilderness Study Area in Delta, Mesa, and Montrose counties, Colorado, contains flat-lying sedimentary rocks of Triassic to Cretaceous age underlain by Proterozoic crystalline rocks. Investigations by the US Geological Survey and US Bureau of Mines revealed that the wilderness study area has low mineral resource potential for metals, including uranium, oil and gas, coal, and geothermal energy. No identified resources are present.

  14. Coal and coalbed methane resources of Cretaceous rocks of the Black Mesa Basin, northeastern Arizona

    SciTech Connect

    Nations, J.D.; Haven, H.W.; Swift, R.L.

    1995-06-01

    Cretaceous rocks of the Black Mesa basin of northeastern Arizona were deposited from Late Cenomanian to Santonian time near the western depositional limit of the transgressive-regressive Greenhorn and Niobrara cyclothems. Coal-bearing rocks of the sequence (including the Dakota Formation, Toreva Formation and Wepo Formation) are preserved in the Black Mesa structural basin of Laramide age. These rocks of the Black Mesa basin are the object of an NSF-sponsored research project to evaluate their coal resources and potential for coalbed methane occurrence. Forty-five measured sections and descriptions of Cretaceous rocks around the eastern margin of the basin have been incorporated into a data base in the software program LOGGER, and have been used to construct a series of stratigraphic cross-sections across the basin using the software program MacSection. These include coal beds and carbonaceous shales that are potential sources of methane as well as reservoirs, and sandstone bodies that are potential secondary reservoirs of methane (and possibly petroleum hydrocarbons from the Mancos Shale). In order to trace the facies changes between measured sections, aerial videography and 35 mm slides have been taken along the entire eastern margin of Black Mesa, a distance of 70 miles. These were digitized to provide detailed lithofacies analyses of the stratigraphic sections along the north-trending cliff line. Trends of thickness variations within these facies are interpreted from isopach maps and known shoreline trends, in order to predict the areas of greatest probability of coalbed methane generation and accumulation. These predictions are also based on the locations of anticlinal and monoclinal fold axes where they cross the thickest coal trends, due to likely enhancement of permeability by cleat and butt fractures in the coal and shale reservoir rocks.

  15. Mesa Public Schools: as Seen through the Eyes of 1982-83 Seniors. RR-51.

    ERIC Educational Resources Information Center

    Troidl, Robert; Peterson, Sarah

    As part of the ongoing process of self-assessment begun with the 1973 Graduate Follow-up Study of the 1971 graduates and continued in 1978 with the 1976 graduates and in 1983 with the 1980 graduates, it was decided to conduct a survey of the 1983 seniors of the Mesa Public Schools during the spring of 1983. The data collected and analyzed at that…

  16. Variation in the annual average radon concentration measured in homes in Mesa County, Colorado

    SciTech Connect

    Rood, A.S.; George, J.L.; Langner, G.H. Jr.

    1990-04-01

    The purpose of this study is to examine the variability in the annual average indoor radon concentration. The TMC has been collecting annual average radon data for the past 5 years in 33 residential structures in Mesa County, Colorado. This report is an interim report that presents the data collected up to the present. Currently, the plans are to continue this study in the future. 62 refs., 3 figs., 12 tabs.

  17. Investigations on the Structure Tectonics, Geophysics, Geochemistry, and Hydrocarbon Potential of the Black Mesa Basin, Northeastern Arizona

    SciTech Connect

    Barker, Colin; Carroll, Herbert; Erickson, Richard; George, Steve; Guo, Genliang; Reeves,T.K.; Sharma, Bijon; Szpakiewicz, Michael; Volk, Len

    1999-04-27

    The U.S. Department of Energy (DOE) has instituted a basin-analysis study program to encourage drilling in underexplored and unexplored areas and increase discovery rates for hydrocarbons by independent oil companies within the continental United States. The work is being performed at the DOE's National Institute for Petroleum and Energy Research (NIPER) in Bartlesville, Oklahoma, by the Exploration and Drilling Group within BDM-Oklahoma (BDM), the manager of the facility for DOE. Several low-activity areas in the Mid-Continent, west, and southwest were considered for the initial study area (Reeves and Carroll 1994a). The Black Mesa region in northwestern Arizona is shown on the U.S. Geological Survey 1995 oil and gas map of the United States as an undrilled area, adapted from Takahashi and Gautier 1995. This basin was selected by DOE s the site for the initial NIPER-BDM survey to develop prospects within the Lower-48 states (Reeves and Carroll 1994b).

  18. Extension of the Stevens Gulch Road and related timber sales, Grand Mesa, Uncompahgre, and Gunnison National Forests in Delta and Mesa counties, Colorado

    SciTech Connect

    Not Available

    1985-08-01

    Extension of Stevens Gulch Road and related timber sales are proposed on the Paonia Ranger District of Grand Mesa, Uncompahgre, and Gunnison National Forests in Delta and Mesa counties, Colorado. The study area comprises 88,466 acres. The preferred alternative would extend the Stevens Gulch Road for 10.6 miles northward from the end of the existing double-lane graveled section to the junction with Buzzard Divide Road. The existing Colorado 133 and Buzzard Divide Road would also be available for access. For timber access, additional local and collector roads would also be built, for a total of 32.7 miles. Stevens Gulch Road, Overland Reservoir Road, Buzzard Divide Road, and Roads 1.1 to 1.5 would remain open to public use. All other local and collector roads would be closed to public use, as would the Hayden-Curecanti Power line Road. A combination of large-volume and slow-volume timber sales would be offered. Spruce-fir timber harvest would be on a 20-year cutting cycle and a 140-year rotation. Aspen timber harvest would be on a 20-year cutting cycle and an 80-year rotation. Over the next decade, timber harvest would reach 25.6 million board feet on 4826 acres. Arterial road building and rebuilding costs would be approximately $1.6 million, and the cost of administering timber sales would be $113.4 thousand. The incremental cost/benefit ratio is 1.83.

  19. Variability of the Tsushima Warm Current during the Pleistocene and its relationship with the evolution of the East Asian Monsoon. Preliminary results from IODP Expedition 346 (Sites U1427 and U1428/29) based on benthic ostracod assemblages.

    NASA Astrophysics Data System (ADS)

    Bassetti, M. A.; Alvarez Zarikian, C. A.; Toucanne, S.; Yasuhara, M.; Holbourn, A. E.; Sagawa, T.; Tada, R.; Murray, R. W.

    2014-12-01

    The semi-enclosed marginal sea bordered by the Eurasian continent, the Korean peninsula and the Japanese Islands has an average depth of 1350 m and is connected with other marginal seas in the region by shallow and narrow straits. At present, the Tsushima Warm Current (TWC), a branch of the Kuroshio Current, is the only warm current flowing into the marginal sea west of Japan. The TWC carries both subtropical water originating from the North Pacific and fresher runoff water derived from East China Sea continental shelf. The northerly flow of the TWC through the shallow Tsushima Straits is ultimately controlled by relative sea level variations over time. IODP Expedition 346 Sites U1427 and U1428/29 are ideally located to record changes in (i) the intensity of the influx of the TWC, and (ii) the intermediate ventilation of the marginal sea over the last million years. The Japan Sea Intermediate Water (JSIW) corresponds to a vertical salinity minimum, found below the TWC, between 200 and 400-500 m water depth. The JSIW shows a relatively high oxygen concentration, related to the deep water convection in winter and linked to fresh water supply during winter monsoon intervals. Based on recent observations, it is thought during glacial and interglacial conditions, and millennial scale climate cycles the intensity of deep and intermediate water currents varied but the mechanisms of such variations are not fully known. Microfossil faunal proxies can be used for tracking bottom environmental conditions related to variability of the bottom water circulation intensity. Here, we present preliminary results obtained using ostracods (benthic microcrustaceans) that are abundant in the sedimentary sequences recovered at Sites U1427 and U1428/29, and are known to react sensitively to changes in water masses physico-chemical parameters. In particular, the variability of the genus Krithe through time is correlated with the sortable silt (carbonate-free, 10-63 µm sediment size distribution) to infer current speed and bottom water ventilation.

  20. The Confluence of Gangis and Eos Chasmas (5-12 deg S, 31-41 deg W): Geologic, Hydrologic, and Exobiologic Considerations for Landing Site at the East End of Valles Marineris

    NASA Technical Reports Server (NTRS)

    George, J. A.; Clifford, S. M.

    1999-01-01

    Over its 3,500 km length, Valles Marineris exhibits an enormous range of geologic and environmental diversity. At its western end, the canyon is dominated by the tectonic complex of Noctis Labyrinthus; while in the east it grades into an extensive region of chaos where scoured channels and streamlined islands provide evidence of catastrophic floods that spilled into the northern plains. In the central portion of the system, debris derived from the massive interior layered deposits of Candor and Ophir Chasmas spills into the central trough. In other areas, 6 km-deep exposures of Hesperian and Noachian-age canyon wall stratigraphy have collapsed in massive landslides that extend many tens of kilometers across the canyon floor. Ejecta from interior craters, aeolian sediments, and possible volcanics emanating from structurally controlled vents along the base of the scarps, further contribute to the canyon's geologic complexity. Following the initial rifting that gave birth to Valles Marineris, water appears to have been a principal agent in the canyon's geomorphic development an agent whose significance is given added weight by its potential role in both sustaining and preserving evidence of past life. In this regard, the interior layered deposits of Candor, Ophir, and Hebes Chasmas, have been identified as possible lucustrine sediments that may have been laid down in long-standing ice-covered lakes. The potential survival and growth of native organisms in such an environment, or in the aquifers whose disruption gave birth to the chaotic terrain and outflow channels to the north and east of the canyon, raises the possibility that fossil indicators of life may be present in the local sediment and rock. Because of the enormous distances over which these diverse environments occur, identifying a single landing site that maximizes the opportunity for scientific return is not a simple task. However, given the fluvial history and narrow geometry of the canyon, the presence of a single exit at its eastern end provides an opportunity for sampling that appears unequaled elsewhere in the system.

  1. The Confluence of Gangis and Eos Chasmas (5-12 deg S, 31-41 deg W): Geologic, Hydrologic, and Exobiologic Considerations for Landing Site at the East End of Valles Marineris

    NASA Astrophysics Data System (ADS)

    George, J. A.; Clifford, S. M.

    1999-06-01

    Over its 3,500 km length, Valles Marineris exhibits an enormous range of geologic and environmental diversity. At its western end, the canyon is dominated by the tectonic complex of Noctis Labyrinthus; while in the east it grades into an extensive region of chaos where scoured channels and streamlined islands provide evidence of catastrophic floods that spilled into the northern plains. In the central portion of the system, debris derived from the massive interior layered deposits of Candor and Ophir Chasmas spills into the central trough. In other areas, 6 km-deep exposures of Hesperian and Noachian-age canyon wall stratigraphy have collapsed in massive landslides that extend many tens of kilometers across the canyon floor. Ejecta from interior craters, aeolian sediments, and possible volcanics emanating from structurally controlled vents along the base of the scarps, further contribute to the canyon's geologic complexity. Following the initial rifting that gave birth to Valles Marineris, water appears to have been a principal agent in the canyon's geomorphic development an agent whose significance is given added weight by its potential role in both sustaining and preserving evidence of past life. In this regard, the interior layered deposits of Candor, Ophir, and Hebes Chasmas, have been identified as possible lucustrine sediments that may have been laid down in long-standing ice-covered lakes. The potential survival and growth of native organisms in such an environment, or in the aquifers whose disruption gave birth to the chaotic terrain and outflow channels to the north and east of the canyon, raises the possibility that fossil indicators of life may be present in the local sediment and rock. Because of the enormous distances over which these diverse environments occur, identifying a single landing site that maximizes the opportunity for scientific return is not a simple task. However, given the fluvial history and narrow geometry of the canyon, the presence of a single exit at its eastern end provides an opportunity for sampling that appears unequaled elsewhere in the system.

  2. Low leakage current AlGaN/GaN on Si-based Schottky barrier diode with bonding-pad electrode mesa etching

    NASA Astrophysics Data System (ADS)

    Jang, Hyun-Gyu; Na, Jeho; Kim, Jung-Jin; Park, Young-Rak; Lee, Hyun-Soo; Jung, Dong-Yun; Mun, Jae-Kyoung; Ko, Sang Choon; Nam, Eun Soo

    2015-07-01

    Bonding-pad electrode-area-etched AlGaN/GaN on a Si-based Schottky barrier diode (SBD) is fabricated. Electrode mesa etching leads to reverse bias leakage current about one order of magnitude lower than that of SBD without electrode mesa etching, but forward currents do not vary greatly, compared with that in conventional SBD, which has no electrode mesa etching.

  3. Metolachlor metabolite (MESA) reveals agricultural nitrate-N fate and transport in Choptank River watershed.

    PubMed

    McCarty, Gregory W; Hapeman, Cathleen J; Rice, Clifford P; Hively, W Dean; McConnell, Laura L; Sadeghi, Ali M; Lang, Megan W; Whitall, David R; Bialek, Krystyna; Downey, Peter

    2014-03-01

    Over 50% of streams in the Chesapeake Bay watershed have been rated as poor or very poor based on the index of biological integrity. The Choptank River estuary, a Bay tributary on the eastern shore, is one such waterway, where corn and soybean production in upland areas of the watershed contribute significant loads of nutrients and sediment to streams. We adopted a novel approach utilizing the relationship between the concentration of nitrate-N and the stable, water-soluble herbicide degradation product MESA {2-[2-ethyl-N-(1-methoxypropan-2-yl)-6-methylanilino]-2-oxoethanesulfonic acid} to distinguish between dilution and denitrification effects on the stream concentration of nitrate-N in agricultural subwatersheds. The ratio of mean nitrate-N concentration/(mean MESA concentration * 1000) for 15 subwatersheds was examined as a function of percent cropland on hydric soil. This inverse relationship (R(2)=0.65, p<0.001) takes into consideration not only dilution and denitrification of nitrate-N, but also the stream sampling bias of the croplands caused by extensive drainage ditch networks. MESA was also used to track nitrate-N concentrations within the estuary of the Choptank River. The relationship between nitrate-N and MESA concentrations in samples collected over three years was linear (0.95 ≤ R(2) ≤ 0.99) for all eight sampling dates except one where R(2)=0.90. This very strong correlation indicates that nitrate-N was conserved in much of the Choptank River estuary, that dilution alone is responsible for the changes in nitrate-N and MESA concentrations, and more importantly nitrate-N loads are not reduced in the estuary prior to entering the Chesapeake Bay. Thus, a critical need exists to minimize nutrient export from agricultural production fields and to identify specific conservation practices to address the hydrologic conditions within each subwatershed. In well drained areas, removal of residual N within the cropland is most critical, and practices such as cover crops which sequester the residual N should be strongly encouraged. In poorly drained areas where denitrification can occur, wetland restoration and controlled drained structures that minimize ditch flow should be used to maximize denitrification. PMID:24388901

  4. Analysis of stratigraphic barriers (caprock) between sands in the cretaceous Mesa Verde formation, US DOE Multiwell Experiment, Garfield County, Colorado

    SciTech Connect

    Soeder, D.J.

    1984-03-01

    Pressure differences between the caprock tests performed and the in-situ reservoir pressures at the Multiwell site preclude any conclusions as to whether drawdown of one sandstone could result in production from an adjacent sand by gas breaching the stratigraphic barriers. On the other hand, the caprock tests performed at IGT do provide the following useful conclusions: (1) In-situ water permeability of the stratigraphic barrier material is extremely low. (2) There is a fairly good inverse correlation between permeability to water and threshold pressure. (3) All of the permeability and threshold pressure data was taken on these samples in a vertical direction. Because of the layered and laminated structure of these rocks, one would expect to find far different numbers in a horizontal direction. This has implications with regard to horizontal flow between adjacent sand lenses at the same depth, as opposed to vertical flow between underlying and overlying sand bodies. (4) Although a few of the barrier cores appeared marginally adequate to transmit gas between sand units based on the CTA data, whether they will do so in the ground is doubtful. (5) The material most likely to allow gas migration between sand lenses was that in the Coastal Zone. (6) It is far more likely that if gas migration occurs between sand lenses in the Multiwell, gas will move through the barrier material by way of natural or man-made fractures. Fracture permeability is probably many orders of magnitude higher than the ultra-tight shale and siltstone matrix, and threshold pressure in a fracture is quite low. The tests performed by IGT, however, were done on carefully chosen, unfractured core, and we have no information on the dynamics of gas movement through fractured stratigraphic barriers. The stratigraphic barrier material between sand lenses in the Mesa Verde at the Multiwell site would make an excellent caprock for an underground gas storage field. 11 figures, 2 tables.

  5. Intercellular Adhesion Molecule 1 and Progression of Percent Emphysema: The MESA Lung Study

    PubMed Central

    Aaron, Carrie P.; Schwartz, Joseph E.; Bielinski, Suzette J.; Hoffman, Eric A.; Austin, John H. M.; Oelsner, Elizabeth C.; Donohue, Kathleen M.; Kalhan, Ravi; Berardi, Cecilia; Kaufman, Joel D.; Jacobs, David R.; Tracy, Russell P.; Barr, R.Graham

    2014-01-01

    Endothelial intercellular adhesion molecule (ICAM) 1 binds neutrophils and facilitates their transmigration into the lung; E-selectin facilitates leukocyte rolling. As neutrophils contribute to tissue destruction in emphysema and chronic obstructive pulmonary disease, we hypothesized that soluble ICAM-1 (sICAM-1) and E-selectin (sE-selectin) would be associated with longitudinal progression of emphysema and lung function decline. The Multi-Ethnic Study of Atherosclerosis (MESA) enrolled participants 45-84 years old without clinical cardiovascular disease in 2000-02. The MESA Lung Study assessed percent emphysema (<-950 Hounsfield units) on cardiac (2000-07) and full-lung CT scans (2010-12), and spirometry was assessed twice over five years. sICAM-1 and sE-selectin were measured at baseline. Mixed-effect models adjusted for demographics, anthropometry, smoking, C-reactive protein, sphingomyelin and scanner factors. Among 1,865 MESA Lung participants with measurement of sICAM-1 and percent emphysema the mean log-sICAM-1 was 5.5±0.3 ng/mL and percent emphysema increased 0.73 percentage points (95% CI: 0.34, 1.12; P<0.001) over ten years. A one SD increase in sICAM-1 was associated with an accelerated increase in percent emphysema of 0.23 percentage points over ten years (95% CI: 0.06, 0.39; P=0.007). No significant association was found for sE-selectin, or between any adhesion molecule and lung function. Higher levels of sICAM-1 were independently associated with progression of percent emphysema in a general population sample. PMID:25457724

  6. Assessing Hydraulic Connections Across Structural Blocks, Pahute Mesa, Nevada—Detecting Distant Drawdowns

    NASA Astrophysics Data System (ADS)

    Garcia, C.; Fenelon, J. M.; Halford, K. J.; Sweetkind, D. S.

    2010-12-01

    Groundwater beneath Pahute Mesa flows through a complexly layered sequence of volcanic-rock aquifers and confining units that have been faulted into distinct structural blocks. Hydraulic properties of the rocks and structures in this aquifer system control radionuclide migration away from areas of underground testing. Detecting drawdowns in observation wells that penetrate a structural block different from the structural block intersected by the pumping well provides irrefutable evidence of a hydraulic connection. However, detecting these pumping-induced changes in water-level records typical of Pahute Mesa can be problematic because environmental noise frequently exceeds the pumping signal. Therefore, inherent noise must be removed from the water-level record systematically before pumping-induced drawdown and subsequent recovery can be quantified and analyzed. Successful applications of this approach on Pahute Mesa are illustrated using water-level records acquired during selected periods of recent drilling, development, testing, and pumping. Continuous monitoring of water level and air pressure changes in two dozen wells reveal moderate and high frequency stresses such as barometric pressure and earth tides along with gradual water-level changes induced by well drilling, development, and testing. At distances of nearly 4 km from pumping stresses, drawdown and recovery responses of less than 0.02 m can be detected using a synthetic water-level analysis. Synthetic water-levels are the summation of barometric, tidal, and pumping responses and water levels from background wells that are fit to measured water levels in remote observation wells. Pumping responses are simulated by superposition of Theis solutions. Differences between synthetic and measured water levels are minimized by adjusting the amplitude and phase of non-pumping components, while the transmissivity and storage coefficient are estimated from the pumping responses.

  7. Porosity, permeability, and pore structure of the tight Mesa Verde sandstone, Piceance Basin, CO

    SciTech Connect

    Soeder, D.J.; Randolph, P.L.

    1984-09-01

    Special core analyses on 44 tight Mesa Verde sandstone samples from the U.S. DOE Multiwell Experiment were combined with petrographic investigations in an attempt to relate the porosity and permeability of the cores to the pore structure of the rocks. Core analysis was performed on one inch (2.54 cm) diameter horizontal plug samples using a computerized steady-state flow measuring device. This equipment routinely measures flow rates with a resolution of better than 10/sup -6/ cm/sup 3//sec. All samples were selected from intervals expected to be gas productive on the basis of wireline well logs, and were taken from the portion of the interval that showed the lowest gamma ray log response. The core plugs were measured for dry permeability to gas, relative permeability at various water saturations, porosity to gas, and pore volume compressibility. Petrographic samples were taken directly off the plug ends and were analyzed with both an optical microscope and a scanning electron microscope. The petrographic study was explicitly directed toward observing the flow paths and pore structure that had been deduced from the core analysis data. Petrographic observations revealed that the pore geometry of sandstone can be broken down into three categories: grain-supported pores, solution pores connected by narrow intergranular slots (the most common pore structure in the Mesa Verde) and matrix supported grains. Core analysis measurements correlated fairly well with pore geometry. Solution pores connected by slots varied by a factor of two in porosity and pore volume compressibility; the dry permeability values fell within the range of 0.1 to 10.0 microdarcies. Calculation of slot-like flow path dimensions from the permeability data revealed a characteristic width of only about 0.1 micron. Special core analysis of the Mesa Verde also showed trends that correlated with various depositional environments in the formation.

  8. Estimate of tilt instability of mesa-beam and Gaussian-beam modes for advanced LIGO

    SciTech Connect

    Savov, Pavlin; Vyatchanin, Sergey

    2006-10-15

    Sidles and Sigg have shown that advanced LIGO interferometers will encounter a serious tilt instability, in which symmetric tilts of the mirrors of an arm cavity cause the cavity's light beam to slide sideways, so its radiation pressure exerts a torque that increases the tilt. Sidles and Sigg showed that the strength T of this torque is 26.2 times greater for advanced LIGO's baseline cavities - nearly flat spherical mirrors which support Gaussian beams (FG cavities), than for nearly concentric spherical mirrors which support Gaussian beams (CG cavities) with the same diffraction losses as the baseline case: T{sup FG}/T{sup CG}=26.2. This has motivated a proposal to change the baseline design to nearly concentric, spherical mirrors. In order to reduce thermal noises in advanced LIGO, O'Shaughnessy and Thorne have proposed replacing the spherical mirrors and their Gaussian beams by ''Mexican-Hat'' (MH) shaped mirrors which support flat-topped, mesa shaped beams. In this paper, we compute the tilt-instability torque for advanced-LIGO cavities with nearly flat MH mirrors and mesa beams (FM cavities) and nearly concentric MH mirrors and mesa beams (CM cavities), with the same diffraction losses as in the baseline FG case. We find that the relative sizes of the restoring torques are T{sup CM}/T{sup CG}=0.91, T{sup FM}/T{sup CG}=96, T{sup FM}/T{sup FG}=3.67. Thus, the nearly concentric MH mirrors have a weaker tilt instability than any other configuration. Their thermoelastic noise is the same as for nearly flat MH mirrors, and is much lower than for spherical mirrors.

  9. Metolachlor metabolite (MESA) reveals agricultural nitrate-N fate and transport in Choptank River watershed

    USGS Publications Warehouse

    McCarty, Gregory W.; Hapeman, Cathleen J.; Rice, Clifford P.; Hively, W. Dean; McConnell, Laura L.; Sadeghi, Ali M.; Lang, Megan W.; Whitall, David R.; Bialek, Krystyna; Downey, Peter

    2014-01-01

    Over 50% of streams in the Chesapeake Bay watershed have been rated as poor or very poor based on the index of biological integrity. The Choptank River estuary, a Bay tributary on the eastern shore, is one such waterway, where corn and soybean production in upland areas of the watershed contribute significant loads of nutrients and sediment to streams. We adopted a novel approach utilizing the relationship between the concentration of nitrate-N and the stable, water-soluble herbicide degradation product MESA {2-[2-ethyl-N-(1-methoxypropan-2-yl)-6-methylanilino]-2-oxoethanesulfonic acid} to distinguish between dilution and denitrification effects on the stream concentration of nitrate-N in agricultural subwatersheds. The ratio of mean nitrate-N concentration/(mean MESA concentration * 1000) for 15 subwatersheds was examined as a function of percent cropland on hydric soil. This inverse relationship (R2 = 0.65, p 2 ≤ 0.99) for all eight sampling dates except one where R2 = 0.90. This very strong correlation indicates that nitrate-N was conserved in much of the Choptank River estuary, that dilution alone is responsible for the changes in nitrate-N and MESA concentrations, and more importantly nitrate-N loads are not reduced in the estuary prior to entering the Chesapeake Bay. Thus, a critical need exists to minimize nutrient export from agricultural production fields and to identify specific conservation practices to address the hydrologic conditions within each subwatershed. In well drained areas, removal of residual N within the cropland is most critical, and practices such as cover crops which sequester the residual N should be strongly encouraged. In poorly drained areas where denitrification can occur, wetland restoration and controlled drained structures that minimize ditch flow should be used to maximize denitrification.

  10. Uranium-bearing coal and carbonaceous shale in La Ventana Mesa area, Sandoval County, New Mexico

    USGS Publications Warehouse

    Vine, James D.; Bachman, George O.; Read, Charles B.; Moore, George W.

    1953-01-01

    Uranium-bearing coal, carboanceous shale, and carboaceous sandstone of Upper Cretaceous age occur on and adjacent to La Ventana Mesa, Sandoval County, New Mexico.  The geologic features of the uranium deposits are described and a hypothesis for the origin and control of the uranium deposits are described and a hypothesis for the origin and control of the uranium deposits is given.  On the basis of recent sampling and analyses the uranium content in coal is found to be as much as 0.62 percent, whereas the coal ash has a uranium content that is as much as 1.34 percent.

  11. The MESA polarimetry chain and the status of its double scattering polarimeter

    SciTech Connect

    Aulenbacher, K.; Bartolomé, P. Aguar; Molitor, M.; Tioukine, V.

    2013-11-07

    We plan to have two independent polarimetry systems at MESA based on totally different physical processes. A first one tries to minimize the systematic uncertainties in double polarized Mo/ller scattering, which is to be achieved by stored hydrogen atoms in an atomic trap (Hydro-Mo/ller-Polarimeter). The other one relies on the equality of polarizing and analyzing power which allows to measure the effective analyzing power of a polarimeter with very high accuracy. Since the status of Hydro-Mo/ller is presented in a separate paper we concentrate on the double scattering polarimeter in this article.

  12. Cutoff-mesa isolated rib optical waveguide for III-V heterostructure photonic integrated circuits

    DOEpatents

    Vawter, G.A.; Smith, R.E.

    1998-04-28

    A cutoff mesa rib waveguide provides single-mode performance regardless of any deep etches that might be used for electrical isolation between integrated electrooptic devices. Utilizing a principle of a cutoff slab waveguide with an asymmetrical refractive index profile, single mode operation is achievable with a wide range of rib widths and does not require demanding etch depth tolerances. This new waveguide design eliminates reflection effects, or self-interference, commonly seen when conventional rib waveguides are combined with deep isolation etches and thereby reduces high order mode propagation and crosstalk compared to the conventional rib waveguides. 7 figs.

  13. SEMICONDUCTOR MATERIALS: A novel compensation method for polygonized mesa structures on (100) silicon substrate

    NASA Astrophysics Data System (ADS)

    Han, Zhang; Weihua, Li

    2010-06-01

    A theoretical compensation method for polygonized mesa structures on (100) silicon substrate during the anisotropic etching process has been developed, which contains four stages as follows: prepare the information of the etching condition; predict the structure's undercutting profile; construct the topological structure of compensation patterns; and generate practical compensation patterns from the topological structure. The reasoning process is clearly stated, and detailed steps for the undercutting prediction and topological structure construction are summarized. Conclusions are also drawn about the rules which must be obeyed during the pattern generation process. The simulation and experimental results of some polygon structures are finally given to prove this method's validity and reliability.

  14. Cutoff-mesa isolated rib optical waveguide for III-V heterostructure photonic integrated circuits

    DOEpatents

    Vawter, Gregory A.; Smith, Robert E.

    1998-01-01

    A cutoff mesa rib waveguide provides single-mode performance regardless of any deep etches that might be used for electrical isolation between integrated electrooptic devices. Utilizing a principle of a cutoff slab waveguide with an asymmetrical refractive index profile, single mode operation is achievable with a wide range of rib widths and does not require demanding etch depth tolerances. This new waveguide design eliminates reflection effects, or self-interference, commonly seen when conventional rib waveguides are combined with deep isolation etches and thereby reduces high order mode propagation and crosstalk compared to the conventional rib waveguides.

  15. Magnetotelluric study of the Pahute Mesa and Oasis Valley regions, Nye County, Nevada

    USGS Publications Warehouse

    Schenkel, Clifford J.; Hildenbrand, Thomas G.; Dixon, Gary L.

    1999-01-01

    Magnetotelluric data delineate distinct layers and lateral variations above the pre-Tertiary basement. On Pahute Mesa, three resistivity layers associated with the volcanic rocks are defined: a moderately resistive surface layer, an underlying conductive layer, and a deep resistive layer. Considerable geologic information can be derived from the conductive layer which extents from near the water table down to a depth of approximately 2 km. The increase in conductivity is probably related to zeolite zonation observed in the volcanic rock on Pahute Mesa, which is relatively impermeable to groundwater flow unless fractured. Inferred faults within this conductive layer are modeled on several profiles crossing the Thirsty Canyon fault zone. This fault zone extends from Pahute Mesa into Oasis Valley basin. Near Colson Pond where the basement is shallow, the Thirsty Canyon fault zone is several (~2.5) kilometers wide. Due to the indicated vertical offsets associated with the Thirsty Canyon fault zone, the fault zone may act as a barrier to transverse (E-W) groundwater flow by juxtaposing rocks of different permeabilities. We propose that the Thirsty Canyon fault zone diverts water southward from Pahute Mesa to Oasis Valley. The electrically conductive nature of this fault zone indicates the presence of abundant alteration minerals or a dense network of open and interconnected fractures filled with electrically conductive groundwater. The formation of alteration minerals require the presence of water suggesting that an extensive interconnected fracture system exists or existed at one time. Thus, the fractures within the fault zone may be either a barrier or a conduit for groundwater flow, depending on the degree of alteration and the volume of open pore space. In Oasis Valley basin, a conductive surface layer, composed of alluvium and possibly altered volcanic rocks, extends to a depth of 300 to 500 m. The underlying volcanic layer, composed mostly of tuffs, fills the basin with about 3-3.5 km of relief on basement. A fault zone, related to the southern margin of the basin, appears to extend up to a depth of about 500 m. The path of groundwater encountering this fault zone is uncertain but may be either to the southwest towards Beatty or to the south towards Crater Flat.

  16. MISSE-7 MESA Miniaturized Electrostatic Analyzer - Ion Spectra Analysis Preliminary Results

    NASA Astrophysics Data System (ADS)

    Enloe, C. L.; Balthazor, R. L.; McHarg, M. G.; Clark, A. L.; Waite, D.; Wallerstein, A. J.; Wilson, K. A.

    2011-12-01

    The 7th Materials on the International Space Station Experiment (MISSE-7) was launched in November 2009 and retrieved on STS-134 in April 2011. One of the onboard experiments, the Miniaturized Electrostatic Analyzer (MESA), is a small low-cost low-size/weight/power ion and electron spectrometer that was pointed into ram during the majority of the time onboard. Over 800 Mb of data has been obtained by taking spectra every three minutes on-orbit. The data has been analyzed with a novel "parameterizing the parameters" method suitable for on-orbit data analysis using low-cost microcontrollers. Preliminary results are shown.

  17. Thoughts Regarding the Dimensions of Faults at Rainier and Aqueduct Mesas, Nye County, Nevada, Based on Surface and Underground Mapping

    SciTech Connect

    Drellack, S.L.; Prothro, L.B.; Townsend, M.J.; Townsend, D.R.

    2011-02-01

    The geologic setting and history, along with observations through 50 years of detailed geologic field work, show that large-displacement (i.e., greater than 30 meters of displacement) syn- to post-volcanic faults are rare in the Rainier Mesa area. Faults observed in tunnels and drill holes are mostly tight, with small displacements (most less than 1.5 meters) and small associated damage zones. Faults are much more abundant in the zeolitized tuffs than in the overlying vitric tuffs, and there is little evidence that faults extend downward from the tuff section through the argillic paleocolluvium into pre-Tertiary rocks. The differences in geomechanical characteristics of the various tuff lithologies at Rainier Mesa suggest that most faults on Rainer Mesa are limited to the zeolitic units sandwiched between the overlying vitric bedded tuffs and the underlying pre-Tertiary units (lower carbonate aquifer–3, lower clastic confining unit–1, and Mesozoic granite confining unit).

  18. 55. LOOKING EAST FROM HEAD OF PLANE 2 EAST. POWER ...

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

    55. LOOKING EAST FROM HEAD OF PLANE 2 EAST. POWER HOUSE AND FLUME VISIBLE TO RIGHT, TAILRACE RUNNING THROUGH CENTER OF PHOTOGRAPH. CRADLE TO INCLINED PLANE 3 EAST IS VISIBLE IN BACKGROUND TO LEFT. - Morris Canal, Phillipsburg, Warren County, NJ

  19. 8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL ...

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

    8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL CONFIGURATION AND LATERAL BRACING, STEEL MESH FLOOR, METAL RAILINGS, AND PORTION OF EAST APPROACH - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  20. 2. VIEW EAST, East Control Area, west radar tower in ...

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

    2. VIEW EAST, East Control Area, west radar tower in foreground, east radar lower in background - Newport NIKE Missile Battery D-57/58, Integrated Fire Control Area, Newport Road, Carleton, Monroe County, MI

  1. The (East) Indian Woman.

    ERIC Educational Resources Information Center

    Naidoo, Josephine

    The focus of this paper is on the social, cultural, and psychological problems women of East Indian origin share with other immigrant women in Canada. Also examined are problems that are unique to the East Indian woman and the ways in which she deals with the challenges, conflicting cultural values, and expectations that confront her. The…

  2. The Middle East.

    ERIC Educational Resources Information Center

    Blouin, Virginia; And Others

    This sixth grade resource unit focuses on Middle East culture as seen through five areas of the social sciences: anthropology-sociology, geography, history, economics, and political science. Among objectives that the student is expected to achieve are the following: 1) given general information on the Middle East through the use of film, visuals,…

  3. Attributes and characteristics of the Mathematics, Engineering, Science, Achievement (MESA) high school program for first-generation Latino students

    NASA Astrophysics Data System (ADS)

    Flores, Ramon

    This study used a web-based survey collected data from 28 first-generation Latino engineers who participated in the Mathematics, Engineering, Science, Achievement (MESA) program during their high school years. From the set of 28 respondents, 5 volunteered to participate in an optional telephone interview. The purpose of this study was to describe the critical attributes and characteristics of the MESA program that lead to success at both the high school and college levels for first-generation Latino students. Success at the high school level was operationally defined as successfully graduating with a high school diploma. Success at the college level was operationally defined here as college graduation with an engineering degree. Using a mixed-methods technique, the researcher attempted to secure consensus of opinion from a sample population of 28 first-generation Latino engineers. The mixed-methods technique was chosen since it allowed the researcher to draw on the strengths of quantitative and qualitative approaches. According to the findings, the typical respondent felt that mentoring was the attribute of the MESA program that most prepared him to graduate from high school. The respondents felt that the following MESA attributes most helped them transition into an undergraduate engineering program: Academic and University Advising; Enrichment Activities; Career Advising; Field Trips; Mentoring; Scholarship Incentive Awards; and Speakers. The respondents viewed study groups as the MESA attribute that best prepared them to graduate college with an engineering degree. This study was purposefully designed as a descriptive study. Future research is required to extend this work into an evaluative study. This would allow for the generalization of the critical attributes to the general student population serviced by the MESA program.

  4. 14. View of interior, north and east walls featuring sink, ...

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

    14. View of interior, north and east walls featuring sink, facing east (Note: B/W scale on wall in foreground is in 1/2 ft increments) - Nevada Test Site, Reactor Maintenance & Disassembly Complex, Junior Hot Cell, Jackass Flats, Area 25, South of intersection of Roads F & G, Mercury, Nye County, NV

  5. Development of ion-implantation confined, shallow mesa stripe (Pn,Sn)Te/Pb(Te,Se) DH laser diodes

    NASA Technical Reports Server (NTRS)

    Fonstad, C. G.; Harton, A.; Jiang, Y.-N.; Appelman, H.

    1983-01-01

    Preliminary results of a program to develop ion implantation confined, shallow mesa stripe (Pb,Sn)Te laser diodes are presented. The practicality of using a shallow mesa stripe to produce single mode laser output and to increase the single mode tuning range are demonstrated. The first results of p-type ion implantation in the lead-tin salts are also reported. It is shown that sodium and lithium both can be used to convert n-type Pb(Te,Se) to p-type. The implant and anneal procedures are described, and electrical characteristics of Li-implanted layers are presented.

  6. Observations of Screw Dislocation Driven Growth and Faceting During CVD Homoepitaxy on 4H-SiC On-Axis Mesa Arrays

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Trunek, Andrew J.; Powell, J. Anthony; Picard, Yoosuf N.; Twigg, Mark E.

    2009-01-01

    Previous studies of (0001) homoepitaxial growth carried out on arrays of small-area mesas etched into on-axis silicon-face 4H-SiC wafers have demonstrated that spiral growth emanating from at least one screw dislocation threading the mesa is necessary in order for a mesa to grow taller in the <0001> (c-axis vertical) direction while maintaining 4H stacking sequence [1]. However, even amongst mesas containing the screw dislocation step source necessary for vertical c-axis growth, we have observed striking differences in the height and faceting that evolve during prolonged homoepitaxial growths. This paper summarizes Atomic Force Microscopy (AFM), Electron Channeling Contrast Imaging (ECCI), Scanning Electron Microscopy (SEM), and optical microscopy observations of this phenomenon. These observations support our initially proposed model [2] that the observed large variation (for mesas where 3C-SiC nucleation has not occurred) is related to the lateral positioning of a screw dislocation step source within each etched mesa. When the screw dislocation step source is located close enough to the developing edge/sidewall facet of a mesa, the c-axis growth rate and facet angle are affected by the resulting interaction. In particular, the intersection (or near intersection) of the inward-sloping mesa sidewall facet with the screw dislocation appears to impede the rate at which the spiral provides new steps required for c-axis growth. Also, the inward slope of the sidewall facet during growth (relative to other sidewalls of the same mesa not near the screw dislocation) seems to be impeded by the screw dislocation. In contrast, mesas whose screw dislocations are centrally located grow vertically, but inward sloping sidewall facets shrink the area of the top (0001) growth surface almost to the point of vanishing.

  7. Completion Report for Well ER-EC-11 Corrective Action Units 101 and 102: Central and Western Pahute Mesa

    SciTech Connect

    NSTec Environmental Management

    2010-12-01

    Well ER-EC-11 was drilled for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, in support of the Nevada Environmental Restoration Project at the Nevada National Security Site (formerly Nevada Test Site), Nye County, Nevada. The well was drilled in September and October 2009 as part of the Pahute Mesa Phase II drilling program. A main objective was to investigate radionuclide migration down-gradient from Well Cluster ER-20-5 and Well ER-20-7 and across the northern Timber Mountain moat structural zone into the area referred to as the Bench, between Pahute Mesa and the Timber Mountain caldera complex. A secondary purpose of the well was to provide detailed hydrogeologic information for the shallow- to intermediate-depth Tertiary volcanic section in the Bench area. This well also provided detailed hydrogeologic information in the Tertiary volcanic section to reduce uncertainties within the Pahute Mesa-Oasis Valley hydrostratigraphic framework model (Bechtel Nevada, 2002). The main 52.1-centimeter hole was drilled to a depth of 507.5 meters and then opened to a diameter of 66.0 centimeters. It was cased with 50.8-centimeter casing to 504.9 meters. The hole diameter was then decreased to 47.0 centimeters, and drilling continued to a total depth of 979.3 meters. It was then cased with 34.0-centimeter casing set at 965.5 meters. The hole diameter was then decreased to 31.1 centimeters and the borehole was drilled to a total depth of 1,264.3 meters. The completion casing string, set to the depth of 1,262.5 meters, consists of 19.4-centimeter stainless-steel casing hanging from 19.4-centimeter carbon-steel casing. The stainless-steel casing has two slotted intervals open to the Tiva Canyon and Topopah Spring aquifers. Four piezometer strings were installed in Well ER-EC-11. A string of carbon-steel 6.0-centimeter tubing with one slotted interval was inserted outside the 50.8-centimeter casing, within the 66.0-centimeter borehole for access to the Timber Mountain aquifer, and landed at 475.3 meters. A second string of 6.0-centimeter tubing with one slotted interval was inserted outside the 34.0-centimeter casing, within the 47.0-centimeter borehole for access to the Benham aquifer, and landed at 911.7 meters. A third piezometer string consists of 7.3-centimeter stainless-steel tubing that hangs from 6.0-centimeter carbon-steel tubing via a crossover sub. This string was landed at 1,029.5 meters to monitor the Tiva Canyon aquifer. The deepest string of 7.3-centimeter tubing was landed at 1,247.8 meters to monitor the Topopah Spring aquifer. Data collected during and shortly after hole construction include composite drill cuttings samples collected every 3.0 meters, 67 percussion gun and rotary sidewall core samples, various geophysical logs, fluid samples (for groundwater chemistry analysis and tritium measurements), and water-level measurements. The well penetrated 1,264.3 meters of Tertiary volcanic rock, including three saturated welded-tuff aquifers and one saturated lava-flow aquifer. A water level was measured in the Timber Mountain aquifer at 449.6 meters, during open-hole geophysical logging on September 20, 2009. The fluid level measured after the total depth was reached and the upper aquifer was cased off was 450.0 meters when measured in the open borehole on October 17, 2009. Measurements on samples taken from the undeveloped well indicated that tritium levels averaging approximately 12,430 picocuries per liter (less than Safe Drinking Water Act levels) were encountered within the Benham aquifer. Tritium was below the minimum detectable activity concentration for samples collected from the Tiva Canyon aquifer and the Topopah Spring aquifer.

  8. Differential Sensitivity Theory applied to the MESA2D code for multi-material problems

    SciTech Connect

    Henninger, R.J.; Maudlin, P.J.; Harstad, E.N.

    1996-05-01

    The technique called Differential Sensitivity Theory (DST) is extended to the multi-component system of equations solved by the MESA2D hydrocode. DST uses adjoint techniques to determine exact sensitivity derivatives, i.e., if R is a calculation result of interest (response R) and {alpha}{sub i} is a calculation input (parameter {alpha}{sub i}), then {partial_derivative}R/{partial_derivative}{alpha}{sub i} is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem {ital all} n sensitivities can be obtained by integrating the solutions from only {ital two} calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics (ACM) code. Previous papers have described application of the technique to one-dimensional, single-material problems. This work presents the derivation and solution of the additional adjoint equations for the purpose of computing sensitivities for two-dimensional, multi-component problems. As an example, results for a multi-material flyer plate impact problem featuring an oblique impact are given. {copyright} {ital 1996 American Institute of Physics.}

  9. Differential Sensitivity Theory applied to the MESA2D code for multi-material problems

    NASA Astrophysics Data System (ADS)

    Henninger, R. J.; Maudlin, P. J.; Harstad, E. N.

    1996-05-01

    The technique called Differential Sensitivity Theory (DST) is extended to the multi-component system of equations solved by the MESA2D hydrocode. DST uses adjoint techniques to determine exact sensitivity derivatives, i.e., if R is a calculation result of interest (response R) and αi is a calculation input (parameter αi), then ∂R/∂αi is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem all n sensitivities can be obtained by integrating the solutions from only two calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics (ACM) code. Previous papers have described application of the technique to one-dimensional, single-material problems. This work presents the derivation and solution of the additional adjoint equations for the purpose of computing sensitivities for two-dimensional, multi-component problems. As an example, results for a multi-material flyer plate impact problem featuring an oblique impact are given.

  10. Differential sensitivity theory applied to the MESA2D code for multi-material problems

    SciTech Connect

    Henninger, R.J.; Maudlin, P.J.; Harstad, E.N.

    1995-09-01

    The technique called Differential Sensitivity Theory (DST) is extended to the multi-component system of equations solved by the MESA2D hydrocode. DST uses adjoint techniques to determine exact sensitivity derivatives, i.e., if R is a calculation result of interest (response R) and {alpha}{sub i} is a calculation input (parameter {alpha}{sub i}), then {partial_derivative}R/{partial_derivative}{alpha}{sub i} is defined as the sensitivity. The advantage of using DST is that for an n-parameter problem all n sensitivities can be obtained by integrating the solutions from only two calculations, a MESA calculation and its corresponding adjoint calculation using an Adjoint Continuum Mechanics (ACM) code. Previous papers have described application of the technique to one-dimensional, single-material problems. This work presents the derivation and solution of the additional adjoint equations for the purpose of computing sensitivities for two-dimensional, multi-component problems. As an example, results for a multi-material flyer plate impact problem featuring an oblique impact are given.

  11. Mesa Isochrones and Stellar Tracks (MIST). I. Solar-scaled Models

    NASA Astrophysics Data System (ADS)

    Choi, Jieun; Dotter, Aaron; Conroy, Charlie; Cantiello, Matteo; Paxton, Bill; Johnson, Benjamin D.

    2016-06-01

    This is the first of a series of papers presenting the Modules for Experiments in Stellar Astrophysics (MESA) Isochrones and Stellar Tracks (MIST) project, a new comprehensive set of stellar evolutionary tracks and isochrones computed using MESA, a state-of-the-art open-source 1D stellar evolution package. In this work, we present models with solar-scaled abundance ratios covering a wide range of ages (5≤slant {log}({Age}) [{year}]≤slant 10.3), masses (0.1≤slant M/{M}ȯ ≤slant 300), and metallicities (-2.0≤slant [{{Z}}/{{H}}]≤slant 0.5). The models are self-consistently and continuously evolved from the pre-main sequence (PMS) to the end of hydrogen burning, the white dwarf cooling sequence, or the end of carbon burning, depending on the initial mass. We also provide a grid of models evolved from the PMS to the end of core helium burning for -4.0≤slant [{{Z}}/{{H}}]\\lt -2.0. We showcase extensive comparisons with observational constraints as well as with some of the most widely used existing models in the literature. The evolutionary tracks and isochrones can be downloaded from the project website at http://waps.cfa.harvard.edu/MIST/.

  12. Evolution of antibiotic resistance on a mesa-shaped fitness landscape

    NASA Astrophysics Data System (ADS)

    Hermsen, Rutger; Hwa, Terence

    2010-03-01

    Rapid emergence of drug resistance is one of the biggest problems facing treatment of diseases ranging from bacterial infection to cancer. Recently it was found that, due to a novel growth-mediated positive feedback mechanism, the growth rate of bacteria exposed to sub-lethal antibiotic levels can drop abruptly when the drug level exceeds a sharp threshold (c.f. the preceding talk by Barrett Deris). This threshold level depends on the degree of expression and activity of the protein(s) providing antibiotic resistance. In environments with spatially varying antibiotic concentrations, this dependence gives rise to a mesa-shaped fitness landscape which provides a strong selective pressure for increasing the expression/activity of drug resistance near the cliff in the landscape. We have performed theoretical studies of evolution on such mesa-shaped fitness landscapes. These studies indicate a high rate of adaptation along the fitness cliff, often exceeding that of evolution on smooth fitness landscapes. The results of these studies establish a dynamic mechanism of evolution driven by a fitness cliff and environmental variability, and are conceptually distinct from the classical Darwinian notion of climbing a fitness gradient.

  13. Exploration for uranium deposits in the Atkinson Mesa area, Montrose County, Colorado

    USGS Publications Warehouse

    Brew, Daniel Allen

    1954-01-01

    The U.S. Geological Survey explored the Atkinson Mesa area for uranium- and vanadium-bearing deposits from July 2, 1951, to June 18, 1953, with 397 diamond-drill holes that totaled 261,251 feet. Sedimentary rocks of Mesozoic age are exposed in the Atkinson Mesa area. They are: the Brushy Basin member of the Upper Jurassic Morrison formation, the Lower Cretaceous Burro Canyon formation, and the Upper and Lower Cretaceous Dakota sandstone. All of the large uranium-vanadium deposits discovered by Geological Survey drilling are in a series of sandstone lenses in the upper part of the Salt Wash member of the Jurassic Morrison formation. The deposits are mainly tabular and blanket-like, but some elongate pod-shaped masses, locally called "rolls" may be present. The mineralized material consists of sandstone impregnated with a uranium mineral which is probably coffinite, spme carnotite, and vanadium minerals, thought to be mainly corvusite and montroseite. In addition,, some mudstone and carbonaceous material is similarly impregnated. Near masses of mineralized material the sandstone is light gray or light brown, is generally over 40 feet thick, and usually contains some carbonaceous material and abundant disseminated pyrite or limonite stain. Similarly, the mudstone in contact with the ore-bearing sandstone near bodies of mineralized rock is commonly blue gray, as compared to its dominant red color away from ore deposits. Presence and degree of these features are useful guides in exploring for new deposits.

  14. Constructing Mass-radius Relationships of Low Mass Gaseous Exoplanets with MESA

    NASA Astrophysics Data System (ADS)

    Chen, Howard; Rogers, Leslie

    2015-01-01

    To date, over 3500 exoplanets and planetary candidates have been discovered. This astonishing feat allows us to answer a cornerstone question in astronomy and planetary science: what are these 'other worlds' in the solar neighborhood like? Apart from characterization efforts based on observations, a good avenue to explore is to use computer simulations to model the planets' atmospheres and interiors under the influence of stellar irradiation. We present a prescription to extend the stellar evolution code MESA (Modules for Experimental Stellar Astrophysics) to model the thermal evolution of low mass exoplanets having hydrogen-helium envelopes. With the addition of routines treating the planet core luminosity, heavy element enrichment, and mass loss due to hydrodynamic winds, the evolutionary pathways of planets with diverse properties are accurately constrained. Using these dynamic models, we construct mass-radius relationships of planets from 1 to 300 MEarth with varying ages, energy flux received, envelope metallicity and opacity. These relations are benchmarked against previous theoretical studies and the current census of observed planets. In doing so, we demonstrate MESA's ability to incorporate these planetary phenomena in its 1D numerical computations. We anticipate that this versatile, user-friendly code will see widespread applications in complementing future exoplanetary surveys such as K-2, TESS, and PLATO.

  15. Women's self-efficacy perceptions in mathematics and science: Investigating USC-MESA students

    NASA Astrophysics Data System (ADS)

    Hong, Rebecca Cheng-Shun

    This study is an investigation into female high school seniors in the USC-MESA program and how the role of self-efficacy perceptions in mathematics and science relates to their college major choice. Bandura's theory on self-efficacy provides the backdrop for this study. This study is qualitative and takes an ethnographic approach incorporating 23 interviews, 2 focus groups, 49.5 hours of observation, and document analysis. Results show that female high school seniors participating in the USC-MESA program demonstrate a strong self-efficacy perception in mathematics and science through their academic choices and pursuits in high school and beyond. This finding confirms a linear approach in understanding how courses taken in high school contribute to the trajectory of college academic choices. It also challenges the theory of self-efficacy in math and science to examine historically underrepresented populations in the field and the external factors that play a key role in their persistence to pursue STEM fields in college and beyond.

  16. 3. VIEW OF BOOSTER STATION 1 INTERIOR, FACING EAST ...

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

    3. VIEW OF BOOSTER STATION 1 INTERIOR, FACING EAST - Nevada Test Site, Frenchman Flat Test Facility, Well Five Booster Stations, Intersection of 5-03 Road & Short Pole Line Road, Area 5, Frenchman Flat, Mercury, Nye County, NV

  17. Interior view to the east of an empty computer room ...

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

    Interior view to the east of an empty computer room - Over-the-Horizon Backscatter Radar Network, Christmas Valley Radar Site Transmit Sector Six Transmitter Building, On unnamed road west of Lost Forest Road, Christmas Valley, Lake County, OR

  18. 28. ELEVATION LOOKING EAST, ORIGINAL MARCONI ANTENNA POLES WERE 300' ...

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

    28. ELEVATION LOOKING EAST, ORIGINAL MARCONI ANTENNA POLES WERE 300' TALL (AT LEAST TWICE THE HEIGHT OF THOSE APPEARING IN PICTURE). - Marconi Radio Sites, Transmitting, Point Reyes Station, Marin County, CA

  19. 2. VIEW OF OFFICE (FEATURE 11), FACING EAST, SOUTHEAST. MILL ...

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

    2. VIEW OF OFFICE (FEATURE 11), FACING EAST, SOUTHEAST. MILL SITE IS SHOWN IN THE UPPER LEFT CORNER OF PHOTOGRAPH. - Copper Canyon Camp of the International Smelting & Refining Company, Office, Copper Canyon, Battle Mountain, Lander County, NV

  20. 3. UPPER NOTTINGHAM MINE, COLLAPSED ADIT. CAMERA IS POINTED EAST. ...

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

    3. UPPER NOTTINGHAM MINE, COLLAPSED ADIT. CAMERA IS POINTED EAST. - Florida Mountain Mining Sites, Upper Nottingham Mine, West face of Florida Mountain, head of Jacobs Gulch, Silver City, Owyhee County, ID

  1. View of EPA Farm Sioux silo, facing east. Radsafe trailer ...

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

    View of EPA Farm Sioux silo, facing east. Rad-safe trailer is to the left - Nevada Test Site, Environmental Protection Agency Farm, Silo Type, Area 15, Yucca Flat, 10-2 Road near Circle Road, Mercury, Nye County, NV

  2. 29. INTERIOR VIEW TO THE EAST OF ROOM 144, A ...

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

    29. INTERIOR VIEW TO THE EAST OF ROOM 144, A POST-MORTEM CELL IN THE HOT DISASSEMBLY AREA. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  3. Detail view to the east of the Antenna Array ...

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

    Detail view to the east of the Antenna Array - Over-the-Horizon Backscatter Radar Network, Christmas Valley Radar Site Transmit Sector Six Antenna Array, On unnamed road west of Lost Forest Road, Christmas Valley, Lake County, OR

  4. View of EPA Farm metal weather tower, facing east, showing ...

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

    View of EPA Farm metal weather tower, facing east, showing thirty-acre irrigated field - Nevada Test Site, Environmental Protection Agency Farm, Weather Tower, Area 15, Yucca Flat, 10-2 Road near Circle Road, Mercury, Nye County, NV

  5. 5. TIP TOP MINE. EAST SIDE OF STRUCTURE WITH COLLAPSED ...

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

    5. TIP TOP MINE. EAST SIDE OF STRUCTURE WITH COLLAPSED ADIT. CAMERA POINTED WEST. - Florida Mountain Mining Sites, Tip Top Mine, West face Florida Mountain, approximately 150 feet below summit, Silver City, Owyhee County, ID

  6. 2. TIP TOP MINE. NORTH AND EAST SIDE OF HOUSE. ...

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

    2. TIP TOP MINE. NORTH AND EAST SIDE OF HOUSE. CAMERA POINTED SOUTH. - Florida Mountain Mining Sites, Tip Top Mine, West face Florida Mountain, approximately 150 feet below summit, Silver City, Owyhee County, ID

  7. 17. VIEW SHOWING FRONT OF DORMITORYDOOR, LOOKING EAST Marilyn Ziemer, ...

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

    17. VIEW SHOWING FRONT OF DORMITORY-DOOR, LOOKING EAST Marilyn Ziemer, photographer, April 1988 - Los Pinetos Nike Missile Site, Santa Clara Road, Los Angeles National Forest, Sylmar, Los Angeles County, CA

  8. 22. VIEW SHOWING BASE OF RADAR TOWER PLATFORM, LOOKING EAST ...

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

    22. VIEW SHOWING BASE OF RADAR TOWER PLATFORM, LOOKING EAST Everett Weinreb, photographer, April 1988 - Los Pinetos Nike Missile Site, Santa Clara Road, Los Angeles National Forest, Sylmar, Los Angeles County, CA

  9. 4. VIEW SHOWING MESS HALLBARRACKS, LOOKING EAST Everett Weinreb, photographer, ...

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

    4. VIEW SHOWING MESS HALL-BARRACKS, LOOKING EAST Everett Weinreb, photographer, April 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  10. 22. SIDE VIEW OF MISSILE ASSEMBLY BUILDING, LOOKING EAST Everett ...

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

    22. SIDE VIEW OF MISSILE ASSEMBLY BUILDING, LOOKING EAST Everett Weinreb, photographer, March 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  11. 20. FRONT VIEW OF PUMP HOUSE, LOOKING EAST Everett Weinreb, ...

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

    20. FRONT VIEW OF PUMP HOUSE, LOOKING EAST Everett Weinreb, photographer, March 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  12. 10. VIEW WITHIN THE EAST OPERATING GALLERY OF WORK STATION ...

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

    10. VIEW WITHIN THE EAST OPERATING GALLERY OF WORK STATION WITH MANIPULATOR ARMS. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  13. 4. EXTERIOR VIEW TO THE EAST OF THE WEST ELEVATION ...

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

    4. EXTERIOR VIEW TO THE EAST OF THE WEST ELEVATION OF THE COLD ASSEMBLY AREA. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  14. 16. VIEW OF FIRST FLOOR EAST OPERATING GALLERY. NOTE THE ...

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

    16. VIEW OF FIRST FLOOR EAST OPERATING GALLERY. NOTE THE SERIES OF MANIPULATOR ARMS ALONG THE LEFT WALL. - Nevada Test Site, Engine Maintenance Assembly & Disassembly Facility, Area 25, Jackass Flats, Mercury, Nye County, NV

  15. 15. INTERIOR VIEW TO THE EAST OF ROOM 102, A ...

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

    15. INTERIOR VIEW TO THE EAST OF ROOM 102, A MACHINE SHOP ADJACENT TO ASSEMBLY BAY NO. 1. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  16. 8. EXTERIOR VIEW TO THE WEST OF THE EAST ELEVATION ...

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

    8. EXTERIOR VIEW TO THE WEST OF THE EAST ELEVATION OF THE HOT DISASSEMBLY AREA. - Nevada Test Site, Reactor Maintenance Assembly & Dissassembly Facility, Area 25, Jackass Flats, Junction of Roads F & G, Mercury, Nye County, NV

  17. 53. VIEW SHOWING GRAFFITI ON EAST WALL OF STAIRWELL INSIDE ...

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

    53. VIEW SHOWING GRAFFITI ON EAST WALL OF STAIRWELL INSIDE 'CATFISH' SILO Everett Weinreb, photographer, April 1988 - Mount Gleason Nike Missile Site, Angeles National Forest, South of Soledad Canyon, Sylmar, Los Angeles County, CA

  18. 6. RElationship of residence, claim house, east tool shed, barn, ...

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

    6. RElationship of residence, claim house, east tool shed, barn, garage, and pole building to overall farmstead site, looking northwest - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  19. Estimation of sulfate trends at selected national park service sites: Does the wet deposition record parallel the aerosol record?

    SciTech Connect

    Shealy, R.T.; Bowersox, V.C.

    1997-12-31

    Recently temporal trends in sulfate concentration in fine-particle aerosols have been measured at a set of twelve National Park Service (NPS) sites using the Interagency Monitoring of Visual Environments (IMPROVE) network. Trends were computed for each climatological season over the period 1982-1993. The distribution of trend direction was nearly symmetric; of the 48 possible site-season combinations, 11 were negative, 8 positive, and the remainder exhibited no trend. These are surprising findings in the context of nearly constant SO{sub 2} emissions in the East over this period (EPA, 1991) and generally-decreasing trends over the entire US computed from wet deposition sulfate concentrations collected by the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Of particular interest are the three largest positive trends: Grand Canyon exhibited a 4.2% increase in winter, Great Smoky Mountains had an increase of 3.9% in summer, and Shenandoah had an increase of 3.7% in summer, Recently, the latter two sites have been studied over a period more recent than the original study (1982-1995) and the trends are smaller, but they remain positive. It has been suggested that these findings are a statistical artifact: that in a large set of trend tests over many sites and seasons, a few will by chance be found to have statistically significant positive trends, even under the condition of no trends.A special study was undertaken using the subset of the NPS sites with co-located IMPROVE and NADP/NTN samplers. Direct comparison of aerosol sulfur and wet deposition sulfate trends is done to determine their relationship to each other. The NPS sites that qualify as candidates in the study are: Shenandoah, Great Smoky Mountains, Glacier, Yosemite, Grand Canyon, Mesa Verde, and Big Bend Parks.

  20. Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona--2003-04

    USGS Publications Warehouse

    Truini, Margot; Macy, Jamie P.; Porter, Thomas J.

    2005-01-01

    The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2003, total ground-water withdrawals were 7,240 acre-feet, industrial withdrawals were 4,450 acre-feet, and municipal withdrawals were 2,790 acre-feet. From 2002 to 2003, total withdrawals decreased by 10 percent, industrial withdrawals decreased by 4 percent, and municipal withdrawals decreased by 20 percent. Flowmeter testing was completed for 24 municipal wells in 2004. The median difference between pumping rates for the permanent meter and a test meter for all the sites tested was -2.9 percent. Values ranged from -10.9 percent at Forest Lake NTUA 1 to +7.8 percent at Rough Rock NTUA 2. From 2003 to 2004, water levels declined in 6 of 12 wells in the unconfined part of the aquifer, and the median change was -0.1 foot. Water levels declined in 7 of 11 wells in the confined part of the aquifer, and the median change was -2.7 feet. From the prestress period (prior to 1965) to 2003, the median water-level change for 26 wells was -23.2 feet. Median water-level change were -6.1 feet for 14 wells in the unconfined parts of the aquifer and and -72.1 feet for 12 wells in the confined part. Discharges were measured once in 2003 and once in 2004 at four springs. Discharge stayed the same at Pasture Canyon Spring, increased 9 percent at Moenkopi Spring, decreased 26 percent at an unnamed spring near Dennehotso, and decreased 50 percent at Burro Spring. For the past 12 years, discharges from the four springs have fluctuated; however, an increasing or decreasing trend is not apparent. Continuous records of surface-water discharge have been collected from 1976 to 2003 at Moenkopi Wash, 1996 to 2003 at Laguna Creek, 1993 to 2003 at Dinnebito Wash, and 1994 to 2003 at Polacca Wash. Median flows for November, December, January, and February of each water year were used as an index of ground-water discharge to those streams. Since 1995, the median winter flows have decreased for Moenkopi Wash, Dinnebito Wash, and Polacca Wash. Since the first continuous record of surface-water discharge in 1997, there is no consistent trend in the median winter flow for Laguna Creek. In 2004, water samples were collected from 12 wells and 4 springs and analyzed for selected chemical constituents. Dissolved-solids concentrations ranged from 100 to 649 milligrams per liter. Water samples from 11 of the wells and from all the springs had less than 500 milligrams per liter of dissolved solids. There are no appreciable time trends in the chemistry of water samples from 7 wells and 2 springs; increasing trends in dissolved-solids and chloride concentrations were evident from the more than 10 years of data for 2 springs.

  1. A preliminary guidebook for identifying stratigraphic contacts at the Nevada Test Site

    SciTech Connect

    Pawloski, G.A.; McKague, H.L.; Wagoner, J.L.; McKinnis, W.B.

    1992-01-01

    Lithologic variation, regional depositional trends, and the lack of written guidelines have resulted in inconsistencies in the recognition of stratigraphic contacts in drill holes at the Nevada Test Site (NTS). Stratigraphic identification, based on mineralogy of discrete samples, can be augmented by geophysical logs and downhole movies to more accurately and consistently locate contacts between units. Criteria are established for locating the base of the Pahute Mesa ash-flow tuff, the top of the Ammonia Tanks ash-flow tuff, the top of the Ammonia Tanks bedded tuff, and the top and the base of the Rainier Mesa Tuff.

  2. 19. VIEW OF CRUDE ORE BINS FROM EAST. EAST CRUDE ...

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

    19. VIEW OF CRUDE ORE BINS FROM EAST. EAST CRUDE ORE BIN IN FOREGROUND WITH DISCHARGE TO GRIZZLY AT BOTTOM OF VIEW. CONCRETE RETAINING WALL TO LEFT (SOUTH) AND BOTTOM (EAST EDGE OF EAST BIN). - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  3. Comments on Anthony Bruton, Miguel Garcia Lopez, and Raquel Esquiliche Mesa's "Incidental L2 Vocabulary Learning: An Impracticable Term?"

    ERIC Educational Resources Information Center

    Reynolds, Barry Lee

    2012-01-01

    Anthony Bruton, Miguel Garcia Lopez, and Raquel Esquiliche Mesa's "Incidental L2 Vocabulary Learning: An Impracticable Term?" (2011) offers some constructive criticism regarding the conventional terminology used in second language (L2) acquisition research and language pedagogy. Although the author finds much of their evidence reasonable and is…

  4. The effect of dissolution of volcanic glass on the water chemistry in a tuffaceous aquifer, Rainier Mesa, Nevada

    USGS Publications Warehouse

    White, Art F.; Claassen, H.C.; Benson, Larry V.

    1980-01-01

    Geochemistry of ground water associated with the Tertiary tuffs within Rainier Mesa, southern Nevada, was investigated to determine the relative importance of glass dissolution in controlling water chemistry. Water samples were obtained both from interstitial pores in core sections and from free-flowing fractures. Cation com- positions showed that calcium and magnesium decreased as a function of depth in the mesa, as sodium increased. The maximum effect occurs within alteration zones containing clinoptilolite and montmorillonite, suggesting these minerals effectively remove bivalent cations from the system. Comparisons are made between compositions of ground waters found within Rainier Mesa that apparently have not reacted with secondary minerals and compositions of waters produced by experimental dissolution of vitric and crystalline tufts which comprise the principal aquifers in the area. The two tuff phases have the same bulk chemistry but produce aqueous solutions of different chemistry. Rapid parabolic dissolution of sodium and silica from, and the retention of, potassium within the vitric phase verify previous predictions concerning water compositions associated with vitric volcanic rocks. Parabolic dissolution of the crystalline phase results in solutions high in calcium and magnesium and low in silica. Extrapolation of the parabolic dissolution mechanism for the vitric tuff to long times successfully reproduces, at com- parable pH, cation ratios existing in Rainier Mesa ground water. Comparison of mass- transfer rates of the vitric and crystalline tuffs indicates that the apparent higher glass-surface to aqueous-volume ratio associated with the vitric rocks may account for dominance of the glass reaction.

  5. Magnetic field effects on THz radiation from Bi2Sr2CaCu2O8+? mesa structures

    NASA Astrophysics Data System (ADS)

    Kitamura, Takeo; Kashiwagi, Takanari; Tsujimoto, Manabu; Delfanazari, Kaveh; Sawamura, Masashi; Ishida, Kazuya; Sekimoto, Shunsuke; Watanabe, Chiharu; Yamamoto, Takashi; Minami, Hidetoshi; Tachiki, Masashi; Kadowaki, Kazuo

    2013-03-01

    In a previous our study, coherent and continuous electromagnetic radiation phenomena in mesa structures of Bi2Sr2CaCu2O8+? single crystal have been investigated precisely in magnetic fields up to only 150 Oe. This experimental result showed that the emission intensity decreases sharply for the field parallel to the c-axis, while it decreases gradually as increasing magnetic field for the in-plane field. In order to improve the measurement, we developed a new system with a better angular resolution and much wider magnetic field range up to 6 T, and a mesa having much stronger THz emission power. The mesa structure is also changed to the stand-alone type of mesa, which produces higher power THz radiation with ideal distribution of radiation. In this presentation, the recent detailed results will be shown in magnetic fields both parallel and perpendicular to the ab-plane of Bi2212, where the Josephson and pancake vortices are playing an important role for THz radiation. This work was supported in part by CREST-JST, WPI-MANA project (NIMS) and Strategic Initiative category (A) at the University of Tsukuba.

  6. Common base amplifier with 7 - dB gain at 176 GHz in InP mesa DHBT technology

    NASA Technical Reports Server (NTRS)

    Samoska, Lorene; Paidi, V.; Griffith, Z.; Dahlstrom, M.; Wei, Y.; Urteaga, M.; Rodell, M. J. W.; Fung, A.

    2004-01-01

    We report a single stage tunded amplifier that exhibits 7 dB small signal gain at 176 GHz. Common Base topology is chosen as it has the best maximum stable gain (MSG) in this frequency band when compared to common emitter and common collector topologies. The amplifiers are designed and fabricated in InP mesa double heterojunction bipolar transistor (DHBT) technology.

  7. Computer Simulations of Edge Effects in a Small-Area Mesa N-P Junction Diodes: Preprint

    SciTech Connect

    Appel, J.; Sopori, B.; Ravindra, N. M.

    2009-02-01

    In this work, computer simulations are used to determine the influence of edge conditions on the overall performance of mesa diodes under dark and illuminated conditions. In particular, we examine the effect of edge shape on the I-V characteristics of the diode.

  8. Use of Earth Observation Data for Environmental Monitoring in the Horn of Africa within the Framework of MESA IGAD THEMA

    NASA Astrophysics Data System (ADS)

    Atheru, Zachary; Fortunate, Muyambi

    2015-12-01

    The achievements and challenges on the implementation of activities of IGAD Climate Prediction and Applications Centre (ICPAC) regarding the use of Earth Observation data for environmental monitoring in the Horn of Africa within the framework of MESA IGAD THEMA. Examples of the outputs from the Land Degradation Assessment, Natural Habitat Conservation and Forest Monitoring are provided and explained. The difficulties faced in communicating and disseminating information particularly to decision makers are highlighted. Also outlined is the scope and expected results from the Monitoring for Environment and Security in Africa (MESA) IGAD Thematic action and emphasis placed on lessons learnt on (i) developing services from products (ii) strengthening national networks (III) disseminating and communicating information to decision and policy makers, and (iv) capacity building. The overall objective of the MESA programme in the IGAD region is to enhance land degradation mitigation, natural habitats assessment and Forest Monitoring for sustainable management of environmental resources through the use of Earth Observation data. This is done by strengthening the Earth Observation information management capacity of regional and national institutions in order to support decision and policy making processes. The services produce and distribute regularly land degradation index maps, land cover change indicators on IGAD selected Natural Habitats areas, Forest degradation, deforestation extent, vulnerability index map. It also develops the political and policy frameworks that are strengthened to ensure an active and sustainable participation of IGAD member states in global environmental surveillance initiatives and finally give adequate technical capacity of MESA IGAD stakeholders.

  9. 77 FR 53884 - High Mesa Energy, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission High Mesa Energy, LLC; Supplemental Notice That Initial Market- Based Rate Filing Includes Request for Blanket Section 204 Authorization This is a supplemental notice in the above-referenced proceeding, of High...

  10. Comments on Anthony Bruton, Miguel Garcia Lopez, and Raquel Esquiliche Mesa's "Incidental L2 Vocabulary Learning: An Impracticable Term?"

    ERIC Educational Resources Information Center

    Reynolds, Barry Lee

    2012-01-01

    Anthony Bruton, Miguel Garcia Lopez, and Raquel Esquiliche Mesa's "Incidental L2 Vocabulary Learning: An Impracticable Term?" (2011) offers some constructive criticism regarding the conventional terminology used in second language (L2) acquisition research and language pedagogy. Although the author finds much of their evidence reasonable and is

  11. 77 FR 68813 - Notice of Closure of Airport Mesa/Carizzo Creek Shooting Area in Eastern San Diego County, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-16

    ... Bureau of Land Management Notice of Closure of Airport Mesa/Carizzo Creek Shooting Area in Eastern San.../Carrizo Creek shooting area located in eastern San Diego County, California. The closure order prohibits recreational shooting and target practice. The use of firearms will continue to be allowed for...

  12. An inventory of long-lived radionuclides residual from underground nuclear testing at the Nevada test site, 1951-1992.

    PubMed

    Smith, D K; Finnegan, D L; Bowen, S M

    2003-01-01

    An inventory of long-lived radionuclides produced by 828 underground nuclear tests conducted at the Nevada test site (NTS) from 1951 to 1992 includes residual tritium, fission products, actinides, and activation products. Recently, the US Department of Energy approved the declassification of the NTS radionuclide inventory by principal geographic test centers. This permits unclassified publication of radionuclide totals for the Yucca Flat, Pahute Mesa-Area 19, Pahute Mesa-Area 20, Frenchman Flat, and Rainier Mesa/Shoshone Mountain testing locations. Activities are reported as of September 23, 1992, the date of the last underground nuclear test conducted at the NTS, and September 23, 2492, after 500 years of radioactive decay. The availability of these data affords an opportunity for the analysis of the radiologic source term within the boundaries of local hydrogeologic units and provides insight to where radionuclides are sited relative to potential exposure pathways. PMID:12634000

  13. Development of a StrengthsQuest-based Online Orientation Course for the Mathematics Engineering Science Achievement (MESA) Program

    NASA Astrophysics Data System (ADS)

    Farmer, J.

    2009-12-01

    MESA Programs have been established in over 30 community colleges in California. A critical component of the Program is the development of a course that helps new students in the community college and MESA environment to adjust to both college life and begin preparing for a professional career in the math- or science-based fields. To date, programs have developed an eclectic mix of courses to orient their students to their programs and to the college. This includes actual college courses that are credit or non-credit, usually 1 or 2 college units, as well as others that are offered only from within their MESA program that meet several times during the students’ first semester in the MESA Program. At College of the Desert (COD), a one unit orientation course was developed and approved by the Curriculum committee and was offered for the first time in Fall 2001. This class met once per week and consisted of several activities to help the student succeed and provided an opportunity for them to investigate future careers.. A StrengthsQuest assessment was added to this course in Fall 2004 and more and more of the course was impacted by the knowledge that the students gained about themselves from the assessment. One ongoing problem that was experienced with this course was scheduling a time so most of the new students could attend this important class at the beginning of their participation in the MESA Program. A pilot program to offer an online orientation course has been implemented at COD for the past two semesters that utilizes the StrengthsQuest as the initial student assessment and provides several experiences that build on those results. An outline of the components of the course will be presented and its potential will be discussed.

  14. Summary of Well Testing and Analysis, Western Pahute Mesa - Oasis Valley FY 2000 Testing Program

    SciTech Connect

    2002-09-30

    This report summarizes the results of the analysis of the Western Pahute Mesa-Oasis Valley (WPM-OV) well development and testing program that was conducted during fiscal year (FY) 2000. This program included the testing of eight wells: ER-EC-1, ER-EC-6, ER-18-2, ER-EC-7, ER-EC-5, ER-EC-8, ER-EC-2a, and ER-EC-4. The locations of these wells are shown in Figure 1-1. The data collection for the program was documented in individual well development and testing reports. Drilling and well construction information has been documented in individual well completion reports. This summary report is based on the individual well analysis reports.

  15. High-frequency voltage-controlled-oscillator for use with inverted- mesa quartz resonators

    SciTech Connect

    Wessendorf, K.O.

    1996-08-01

    An oscillator circuit has been developed that uses inverted mesa resonators, in a high precision VCO application, at frequencies historically dominated by SAW designs. This design incorporates a frequency tripler that provides a 600 MHz output capability using a 200 MHz 3{sup rd} overtone resonator. This design has advantages over equivalent SAW alternatives: lower power consumption, superior aging characteristics, linear frequency pulling and low frequency versus temperature sensitivity. The VCO presented demonstrates {gt} +/- 60 ppm pullability (0 to 7V control), tuning linearity better than +/- 5% with phase noise at 1 kHz {lt} -110 DBc/Hz. this oscillator- tripler exploits the nonlinear characteristics of an emitter-coupled pair differential amplifier to obtain a high performance oscillator design.

  16. Optimism and Cardiovascular Health: Multi-Ethnic Study of Atherosclerosis (MESA)

    PubMed Central

    Hernandez, Rosalba; Kershaw, Kiarri N.; Siddique, Juned; Boehm, Julia K.; Kubzansky, Laura D.; Diez-Roux, Ana; Ning, Hongyan; Lloyd-Jones, Donald M.

    2015-01-01

    Objectives We examined the cross-sectional association between optimism and cardiovascular health (CVH). Methods We used data collected from adults aged 52–84 who participated in the Multi-Ethnic Study of Atherosclerosis (MESA) (n=5,134) during the first follow-up visit (2002–2004). Multinomial logistic regression was used to examine associations of optimism with ideal and intermediate CVH (with reference being poor CVH), after adjusting for socio-demographic factors and psychological ill-being. Results Participants in the highest quartile of optimism were more likely to have intermediate [OR=1.51:95%CI=1.25,1.82] and ideal [OR=1.92:95%CI=1.30,2.85] CVH when compared to the least optimistic group. Individual CVH metrics of diet, physical activity, BMI, smoking, blood sugar and total cholesterol contributed to the overall association. Conclusions We offer evidence for a cross-sectional association between optimism and CVH. PMID:26213688

  17. Core drilling provides information about Santa Fe Group aquifer system beneath Albuquerque's West Mesa

    USGS Publications Warehouse

    Allen, B.D.; Connell, S.D.; Hawley, J.W.; Stone, B.D.

    1998-01-01

    Core samples from the upper ???1500 ft of the Santa Fe Group in the Albuquerque West Mesa area provide a first-hand look at the sediments and at subsurface stratigraphic relationships in this important part of the basin-fill aquifer system. Two major hydrostratigraphic subunits consisting of a lower coarse-grained, sandy interval and an overlying fine-grained, interbedded silty sand and clay interval lie beneath the water table at the 98th St core hole. Borehole electrical conductivity measurements reproduce major textural changes observed in the recovered cores and support subsurface correlations of hydrostratigraphic units in the Santa Fe Group aquifer system based on geophysical logs. Comparison of electrical logs from the core hole and from nearby city wells reveals laterally consistent lithostratigraphic patterns over much of the metropolitan area west of the Rio Grande that may be used to delineate structural and related stratigraphic features that have a direct bearing on the availability of ground water.

  18. Naturally weathered feldspar surfaces in the Navajo Sandstone aquifer, Black Mesa, Arizona: Electron microscopic characterization

    USGS Publications Warehouse

    Zhu, Chen; Veblen, D.R.; Blum, A.E.; Chipera, S.J.

    2006-01-01

    Naturally weathered feldspar surfaces in the Jurassic Navajo Sandstone at Black Mesa, Arizona, was characterized with high-resolution transmission and analytical electron microscope (HRTEM-AEM) and field emission gun scanning electron microscope (FEG-SEM). Here, we report the first HRTEM observation of a 10-nm thick amorphous layer on naturally weathered K-feldspar in currently slightly alkaline groundwater. The amorphous layer is probably deficient in K and enriched in Si. In addition to the amorphous layer, the feldspar surfaces are also partially coated with tightly adhered kaolin platelets. Outside of the kaolin coatings, feldspar grains are covered with a continuous 3-5 ??m thick layer of authigenic smectite, which also coats quartz and other sediment grains. Authigenic K-feldspar overgrowth and etch pits were also found on feldspar grains. These characteristics of the aged feldspar surfaces accentuate the differences in reactivity between the freshly ground feldspar powders used in laboratory experiments and feldspar grains in natural systems, and may partially contribute to the commonly observed apparent laboratory-field dissolution rate discrepancy. At Black Mesa, feldspars in the Navajo Sandstone are dissolving at ???105 times slower than laboratory rate at comparable temperature and pH under far from equilibrium condition. The tightly adhered kaolin platelets reduce the feldspar reactive surface area, and the authigenic K-feldspar overgrowth reduces the feldspar reactivity. However, the continuous smectite coating layer does not appear to constitute a diffusion barrier. The exact role of the amorphous layer on feldspar dissolution kinetics depends on the origin of the layer (leached layer versus re-precipitated silica), which is uncertain at present. However, the nanometer thin layer can be detected only with HRTEM, and thus our study raises the possibility of its wide occurrence in geological systems. Rate laws and proposed mechanisms should consider the possibility of this amorphous layer on feldspar surface. ?? 2006 Elsevier Inc. All rights reserved.

  19. Testing eccentricity pumping mechanisms to model eccentric long-period sdB binaries with MESA

    NASA Astrophysics Data System (ADS)

    Vos, J.; Østensen, R. H.; Marchant, P.; Van Winckel, H.

    2015-07-01

    Context. Hot subdwarf-B stars in long-period binaries are found to be on eccentric orbits, even though current binary-evolution theory predicts these objects to be circularised before the onset of Roche-lobe overflow (RLOF). Aims: We aim to find binary-evolution mechanisms that can explain these eccentric long-period orbits, and reproduce the currently observed period-eccentricity diagram. Methods: Three different processes are considered; tidally-enhanced wind mass-loss, phase-dependent RLOF on eccentric orbits and the interaction between a circumbinary disk and the binary. The binary module of the stellar-evolution code Modules for Experiments in Stellar Astrophysics (MESA) is extended to include the eccentricity-pumping processes. The effects of different input parameters on the final period and eccentricity of a binary-evolution model are tested with MESA. Results: The end products of models with only tidally-enhanced wind mass-loss can indeed be eccentric, but these models need to lose too much mass, and invariably end up with a helium white dwarf that is too light to ignite helium. Within the tested parameter space, no sdBs in eccentric systems are formed. Phase-dependent RLOF can reintroduce eccentricity during RLOF, and could help to populate the short-period part of the period-eccentricity diagram. When phase-dependent RLOF is combined with eccentricity pumping via a circumbinary disk, the higher eccentricities can be reached as well. A remaining problem is that these models favour a distribution of higher eccentricities at lower periods, while the observed systems show the opposite. Conclusions: The models presented here are potentially capable of explaining the period-eccentricity distribution of long-period sdB binaries, but further theoretical work on the physical mechanisms is necessary. Appendix A is available in electronic form at http://www.aanda.org

  20. Bilayer graphene grown on 4H-SiC (0001) step-free mesas.

    PubMed

    Nyakiti, L O; Myers-Ward, R L; Wheeler, V D; Imhoff, E A; Bezares, F J; Chun, H; Caldwell, J D; Friedman, A L; Matis, B R; Baldwin, J W; Campbell, P M; Culbertson, J C; Eddy, C R; Jernigan, G G; Gaskill, D K

    2012-04-11

    We demonstrate the first successful growth of large-area (200 × 200 μm(2)) bilayer, Bernal stacked, epitaxial graphene (EG) on atomically flat, 4H-SiC (0001) step-free mesas (SFMs) . The use of SFMs for the growth of graphene resulted in the complete elimination of surface step-bunching typically found after EG growth on conventional nominally on-axis SiC (0001) substrates. As a result heights of EG surface features are reduced by at least a factor of 50 from the heights found on conventional substrates. Evaluation of the EG across the SFM using the Raman 2D mode indicates Bernal stacking with low and uniform compressive lattice strain of only 0.05%. The uniformity of this strain is significantly improved, which is about 13-fold decrease of strain found for EG grown on conventional nominally on-axis substrates. The magnitude of the strain approaches values for stress-free exfoliated graphene flakes. Hall transport measurements on large area bilayer samples taken as a function of temperature from 4.3 to 300 K revealed an n-type carrier mobility that increased from 1170 to 1730 cm(2) V(-1) s(-1), and a corresponding sheet carrier density that decreased from 5.0 × 10(12) cm(-2) to 3.26 × 10(12) cm(-2). The transport is believed to occur predominantly through the top EG layer with the bottom layer screening the top layer from the substrate. These results demonstrate that EG synthesized on large area, perfectly flat on-axis mesa surfaces can be used to produce Bernal-stacked bilayer EG having excellent uniformity and reduced strain and provides the perfect opportunity for significant advancement of epitaxial graphene electronics technology. PMID:22352833