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Burrow associates of the gopher tortoise : proceedings of the 8th annual meeting of the Gopher Tortoise Council
No abstract available.
Research and education to improve surface and ground-water quality of a claypan soil--Proceedings of agricultural research to protect water quality
No abstract available.
Soil respiration at the Amargosa Desert Research site: A section in U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)
Automated opaque flux-chamber measurements of soil carbon dioxide (CO 2 ) flux (soil respiration) into the atmosphere at the Amargosa Desert Research Site show seasonal and diel cycles of soil respiration that are closely linked with soil temperature and soil moisture. During 1998, soil respiration increased with soil warming through spring, reaching a maximum rate (not counting anomalously high values scattered through the record) of about 0.055 moles CO 2 m -2 day -1 around Julian Day 120. Respiration rates then declined along with volumetric soil moisture content, tending to stay at or below about 0.02 moles CO 2 per square meter per day (m -2 day -1 ) for the rest of the year, except after summer rainfalls when respiration sharply increased for short periods. The diel respiration pattern during dry spells is marked by a sharp rise in CO 2 flux coincident with steeply rising soil temperatures in the morning, then dropping back to low levels about the time of maximum soil temperature. The reason for this pattern in unclear.
Tritium and 14C concentrations in unsaturated-zone gases at test hole UZB-2, Amargosa Desert Research Site, 1994-98: A section in U.S. Geological Survey Toxic Substances Hydrology Program: Proceedings of the technical meeting, Charleston, South Carolina, March 8-12, 1999: Volume 3 (Part C) (WRI 99-4018C)>
Tritium concentrations have been determined yearly since April 1994 from water-vapor samples collected at test hole UZB-2. The hole was drilled about 100 m (meters) south of the southwest corner of a commercial burial site for low-level radioactive wastes in September 1993. UZB-2 is equipped with ten 2.5-cm (centimeters) diameter air ports permanently installed in the unsaturated zone between the depths of 5.5 and 108.8 m below land surface. Depth to ground water is about 110 m. Additional sampling ports were driven by hand to depths of 0.5, 1.0 and 1.5 m in May 1997. Initial samples of water vapor collected in April 1994 showed elevated tritium concentrations of more than 100 TU (tritium units) from all 10 air ports, with a maximum concentration of 762±10 TU from an air port at a depth of 24.1 m. Subsequent tritium concentrations increased in all air ports, although tritium concentrations at depths of less than 34.1 m have remained relatively constant since July 1995. The largest observed increase in tritium has been at a depth of 47.9 m. There, tritium concentration has increased from 198±5 TU in April 1994 to 2,570±30 TU in June 1998. Large increases also have been measured in samples collected from air ports at depths of 106.4 and 108.8 m, just above the water table. During September and October 1998, carbon dioxide samples were collected from all ten air ports in UZB-2 and at a depth of 1.5 m, and analyzed for radioactive carbon-14 ( 14 C). 14 C concentrations are highest in air ports at depths less than 6 m where they exceed 2,000 pmc (percent modern carbon). Concentrations decrease rapidly in air ports at depth and are about 20 pmc below 94.2 m. However, at 47.9 meters, the 14 C concentration is 205±1 pmc, which is 2 to 4 times higher than concentrations in air ports immediately above and below. This depth corresponds to the largest tritium increase in UZB-2. Concentrations of both tritium and 14 C are greater than what could be expected from atmospheric fallout. The distribution of tritium and 14 C likely represent a complex pattern of lateral and vertical transport through the unsaturated zone from buried wastes to UZB-2.
Topic III - Infiltration and Drainage: A section in Joint US Geological Survey, US Nuclear Regulatory Commission workshop on research related to low-level radioactive waste disposal, May 4-6, 1993, National Center, Reston, Virginia; Proceedings (WRI 95-4015)
Infiltration into and drainage from facilities for the disposal of low-level radioactive wastes is considered the major process by which non-volatile contaminants are transported away from the facilities. The session included 10 papers related to the processes of infiltration and drainage, and to the simulation of flow and transport through the unsaturated zone. The first paper, presented by David Stonestrom, was an overview regarding the application of unsaturated flow theory to infiltration and drainage. Stonestrom posed three basic questions, which are: How well do we know the relevant processes affecting flow and transport? How well can we measure the parametric functions used to quantify flow and transport? How do we treat complexities inherent in field settings? The other nine papers presented during the session gave some insight to these questions. Topics included: laboratory measurement of unsaturated hydraulic conductivities at low water contents, by John Nimmo; use of environmental tracers to identify preferential flow through fractured media and to quantify drainage, by Edmund Prych and Edwin Weeks; field experiments to evaluate relevant processes affecting infiltration and drainage, by Brian Andraski, Glendon Gee, and Peter Wierenga; and the use of determinist'c and stochastic models for simulating flow and transport through heterogeneous sediments, by Richard Hills, Lynn Gelhar, and Shlomo Neuman.
Preface: Proceedings of the First International Snakehead Symposium
No abstract available.
Proceedings of an international workshop on new developments in geographic information systems
No abstract available.
Late Wisconsinan glaciation of New England: A proceeding volume of the symposium: Late Wisconsinan glaciation of New England held at Philadelphia, Pennsylvania March 13, 1980
No abstract available.
Inferring geologic structure from gravity anomalies: Proceed with caution
Characterization of key geologic structures within a study region, such as basin depths, fault offsets, and fault dip, are often derived from gravity data. Gravity modeling of such subsurface geologic structure generally assumes either homogeneous or spatially uncorrelated densities within modeled rock bodies and overlying sediments. This assumption allows modeling to focus on the shape of the subsurface bodies, for example, body depth or fault dip, which then underpin subsequent structural interpretations. However, both surface and drill-hole samples from rock bodies and sediments show a range of density values that exhibit spatial correlation, The spatially-correlated densities add low-frequency noise to the models that is difficult to detect and characterize which can lead to misinterpretations of the subsurface structure.
Proceedings of the Fiscal Year 2022 Annual Reporting Meeting to the Glen Canyon Dam Adaptive Management Program
(Hartwell) This report is prepared primarily to account for work conducted and products delivered in FY 2022 by GCMRC and to inform the Technical Work Group of science conducted by GCMRC and its cooperators in support of the Glen Canyon Dam Adaptive Management Program (GCDAMP). It includes a summary of accomplishments, modifications to work plans, results, and recommendations related to projects included in GCMRC’s FY 2021-23 Triennial Work Plan. This work was done to support the 11 resource goals identified in the Glen Canyon Dam Long-Term Experimental and Management Plan (LTEMP) Environmental Impact Statement and Record of Decision (Table 1).
Proceedings of the Deepwater Hydrate Coring Expedition UT-GOM2-2
This report was the result of a scientific collaboration between the following institutions The University of Texas at Austin (UT), DOE, NETL, the United States Geological Survey (USGS), the Bureau of Ocean Energy Management (BOEM), The Ohio State University, Columbia University, University of New Hampshire, Oregon State University, University of Washington, Tufts University, Colorado School of Mines, and Geotek Ltd. In the summer and fall of 2023, the University of Texas (UT) Deepwater Hydrate Coring Expedition (UT-GOM2-2) drilled, cored, made downhole measurements, and analyzed samples from the seafloor to the base of the gas hydrate stability zone at Site H in the Walker Ridge Protracted Area Block 313 (Site H, WR313) in the Terrebonne basin, deepwater Gulf of America (Gulf of Mexico), herein the Gulf. This report is made up of a series of files as listed below that represents the “expedition report” of the 2023 UT-GOM2-2 Expedition.
Effects of fire on the desert tortoise (Gopherus agassizii). Proceedings of the International Conference on Turtles and Tortoises. Dominguez Hills, CA
No abstract available at this time
Proceedings of the 1977 oil spill response workshop
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Stream classification 1977: proceedings of a workshop held at Pingree Park, Colorado, October 10-13, 1977
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