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Energy related studies utilizing microcline thermochronology: Progress report, May 1, 1987-April 30, 1988

Description: Rock samples from the Salton Sea Geothermal Field (sandstone, tuff, granite) and from accretionary prism sediments along the convergent margins in southeast Alaska and southwest Japan have been dated by the /sup 40/Ar/sup 39/Ar method. Paleotemperatures have been calculated. (ACR
Date: April 30, 1988
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PUFF TOO: a residual stress experiment

Description: Following the passage of the dynamic effects in a contained explosive detonation, there remains a strong compressive stress field in the material about the cavity. In this experiment, a 454-kg (1000 lb) sphere of high explosive was detonated in saturated ashfall tuff. Instrumentation measured peak stresses over the range of 0.1 to 6.0 GPa (1 to 6 kbar) and the complete stress-time waveform, including the so-called residual stress, at the 0.1 GPa (1 kbar) peak stress range. Mineback revealed det… more
Date: April 1, 1980
Creator: Smith, C.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Numerical experiments on the probability of seepage intounderground openings in heterogeneous fractured rock

Description: An important issue for the performance of underground nuclear waste repositories is the rate of seepage into the waste emplacement drifts. A prediction of this rate is particularly complicated for the potential repository site at Yucca Mountain, Nevada, because it is located in thick, unsaturated, fractured tuff formations. Underground opening in unsaturated media might act as capillary barriers, diverting water around them. In the present work, they study the potential rate of seepage into dri… more
Date: April 15, 1998
Creator: Birkholzer, J.; Li, G.; Tsang, C. F. & Tsang, Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Loading technique for dynamic response studies of geological materials

Description: A loading technique to study the dynamic response of tuff was explored. Loading is provided by electrically exploding etched copper mesh patterns with current from a capacitor discharge. Pressure pulses with peak pressures up to 1.25 kbar and 0.10 to 0.20 ms durations were measured with a pressure bar. The upper value of peak pressure was limited by the strength of the experimental apparatus, and higher pressure generation is possible with a redesign of test hardware. 6 figures, 2 tables.
Date: April 1, 1979
Creator: Butler, R. I. & Forrestal, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental study of the dynamic viscosity of some anhydrous silicate melts to 1953 K at 150 kPa. [Alluvium]

Description: The dynamic viscosity was measured for six anhydrous silicate melts, obtained by fusing various rocks collected from the Department of Energy's Nevada Test Site, from 1393 to 1953 K at 150 kPa. These silicate melts exhibit Newtonian behavior in this temperature interval. Experimental results indicate that tuff viscosity > alluvium viscosity > basalt viscosity. At 1673 K, viscosities of Schooner tuff (Ue20..mu..-330'), alluvium (U10ba), and Danny Boy basalt (Ue18q No. 2) are 28,460 Pa.s, 4,820 P… more
Date: April 3, 1979
Creator: Weed, H.C.; Piwinskii, A.J. & Dibley, L.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Porosity, permeability, and their relationship in granite, basalt, and tuff

Description: This report discusses the porosity, storage, and permeability of fractured (mainly crystalline) rock types proposed as host rock for nuclear waste repositories. The emphasis is on the inter-relationships of these properties, but a number of reported measurements are included as well. The porosity of rock is shown to consist of fracture porosity and matrix porosity; techniques are described for determining the total interconnected porosity through both laboratory and field measurement. Permeabil… more
Date: April 1, 1983
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Induced shock propagation on the Non-Proliferation Experiment

Description: The Explosive Effects Physics Project at the Los Alamos National Laboratory planned and conducted experiments on the NPE (Non-Proliferation Experiment) as part of its effort to define source functions for seismic waves. Beyond the explosive chamber, the detonation induced shock propagated through the saturated tuff of the N-tunnel complex. The CORRTEX (COntinuous Reflectometry for Radius vsw Time EXperiment) system was used to investigate the shock propagation in two drill holes and the access … more
Date: April 1, 1994
Creator: McKown, T. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spall study in one dimension

Description: A SOC one-dimensional calculation of an underground nuclear test is presented to exemplify the shock propagation and spall phenomenology commonly predicted. Then to examine the effects of spherical divergence on spall, a series of SOC calculations, at different radii of curvature, are conducted and prediction of depth and velocity for the first spall zone are compared with predictions from simple analytic theory. The excellent agreement in this comparison verifies that the SOC code accurately r… more
Date: April 6, 1976
Creator: Glenn, H. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Predicted Geology of the Pahute Mesa-Oasis Valley Phase II Drilling Initiative

Description: Pahute Mesa–Oasis Valley (PM-OV) Phase II drilling will occur within an area that encompasses approximately 117 square kilometers (45 square miles) near the center of the Phase I PM-OV hydrostratigraphic framework model area. The majority of the investigation area lies within dissected volcanic terrain between Pahute Mesa on the north and Timber Mountain on the south. This area consists of a complex distribution of volcanic tuff and lava of generally rhyolitic composition erupted from nearby ca… more
Date: April 20, 2009
Creator: National Security Technologies, LLC
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of Reducing Groundwater on the Retardation of Redox-Sensitive Radionuclides

Description: Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions used during these experiments were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the t… more
Date: April 21, 2008
Creator: Hu, Q; Zavarin, M & Rose, T P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulation of Ventilation Efficiency, Temperatures, and Relative Humidities in Emplacement Drifts at Yucca Mountain, Nevada, Using Monte Carlo and Composite Thermal-Pulse Methods

Description: Predictions of waste canister and repository driftwall temperatures as a function of space and time are of fundamental importance to evaluating pre-closure and post-closure design requirements and performance assessment of the proposed repository for spent nuclear fuel and high-level radioactive waste at Yucca Mountain, Nevada. Variations in the lithostratigraphic features in densely welded and crystallized rocks of the 12.8-million-year-old Topopah Spring Tuff, especially the porosity resultin… more
Date: April 6, 2004
Creator: Case, J. & Buesch, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pore-water isotopic compositions and unsaturated-zone flow, Yucca Mountain, Nevada

Description: Isotopic compositions of core-water samples from boreholes USW SD-6 and USW WT-24 indicate that recent water has been introduced at depth. Tritium, carbon, oxygen, and deuterium isotopic compositions all support younger water at depth in the two boreholes. Peaks in tritium concentrations in pore-water samples, indicating younger water than the other samples, observed near the basal vitrophyre of the Topopah Spring Tuff and at the bottom of the CHF and the top of the PP in both boreholes SD-6 an… more
Date: April 29, 2001
Creator: Yang, In C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Strontium isotope evolution of pore water and calcite in the Topopah Spring Tuff, Yucca Mountain, Nevada

Description: Pore water in the Topopah Spring Tuff has a narrow range of {delta}{sup 87}Sr values that can be calculated from the {delta}{sup 87}Sr values of the rock considering advection through and reaction with the overlying nonwelded tuffs of the PTn. This model can be extended to estimate the variation of {delta}{sup 87}Sr in the pore water through time; this approximates the variation of {delta}{sup 87}Sr measured in calcite fracture coatings. In samples of calcite where no silica can be dated by oth… more
Date: April 29, 2001
Creator: Marshall, Brian D. & Futa, Kiyoto
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulation of water-rock interaction in the yellowstone geothermal system using TOUGHREACT

Description: The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to accurately simulate water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a seri… more
Date: April 28, 2003
Creator: Dobson, P. F.; Salah, S.; Spycher, N. & Sonnenthal, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fracture characterization of the large-block test, Fran Ridge, Yucca Mountain, Nevada

Description: The US Department of Energy (DOE) is investigating the suitability of Yucca Mountain as a potential site for the nation's first high-level nuclear waste repository. The site is located about 120 km northwest of Las Vegas, Nevada, at the Nevada Test Site. Favorable aspects of Yucca Mountain as a potential repository site include its arid nature and the sorptive properties of the rock materials. The arid environment results in unsaturated conditions at the potential emplacement horizon, which is … more
Date: April 28, 1999
Creator: Wagoner, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Constraining local 3-D models of the saturated-zone, Yucca Mountain, Nevada

Description: A qualitative three-dimensional analysis of the saturated zone flow system was performed for a 8 km {times} 8 km region including the potential Yucca Mountain repository site. Certain recognized geologic features of unknown hydraulic properties were introduced to assess the general response of the flow field to these features. Two of these features, the Solitario Canyon fault and the proposed fault in Drill Hole Wash, appear to constrain flow and allow calibration.
Date: April 1, 1994
Creator: Barr, G.E. & Shannon, S.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of heterogeneity on actinide diffusion rates in tuffaceous rock

Description: The pore structure and mineralogy of Topopah Spring Tuff are heterogeneous on scales less than one cm. This heterogeneity creates spatial variation in transport rates for aqueous actinide species both on the scale of tenths of microns and the scale of mm. The volumetric distribution of fluid paths having very different tortuosity, and potentially differing surface mineralogy and sorptive properties, must be considered in order to provide realistic predictions of transport rates. In addition, si… more
Date: April 1, 1991
Creator: Buchholtz ten Brink, M.; Phinney, D. L. & Smith, D. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Selenite transport in unsaturated tuff from Yucca Mountain

Description: Direct measurements of unsaturated selenite retardation coefficients and unsaturated hydraulic conductivity were obtained on two tuff samples from Yucca Mountain using the UFA{trademark} technology. The retardation factor for the selenite species was only 2.5 in both Yucca Mountain vitric member at 62.6% saturation and zeolitized nonwelded tuff from G-tunnel at 52.8% saturation with respect to J-13 well water from the Nevada Test Site contaminated with selenium at 1.31 mg/l (ppm). In batch test… more
Date: April 1, 1994
Creator: Conca, J.L. & Triay, I.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Actinide transport in Topopah Spring Tuff: Pore size, particle size, and diffusion

Description: Diffusive transport rates for aqueous species in a porous medium are a function of sorption, molecular diffusion, and sample tortuosity. With heterogeneous natural samples, an understanding of the effect of multiple transport paths and sorption mechanisms is particularly important since a small amount of radioisotope traveling via a faster-than-anticipated transport path may invalidate the predictions of transport codes which assume average behavior. Static-diffusion experiments using aqueous {… more
Date: April 1, 1991
Creator: Buchholtz ten Brink, M.; Phinney, D. L. & Smith, D. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Waste-package release rates for site suitability studies

Description: Performance-assessment calculations in support of the site- suitability effort for the Yucca Mountain Project will address radionuclide transport arising from various disruptive scenarios. Here we present release rates of radionuclides from individual waste packages for scenarios involving various postulated forms of water intrusion, including increased infiltration rate as well as rock immediately surrounding an individual waste package becoming saturated with ground water. We examine: (1) eff… more
Date: April 1, 1991
Creator: Lee, W. W. L.; Sadeghi, M. M.; Chambre, P. L. & Pigford, T. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal stability of zeolitic tuff from Yucca Mountain, Nevada

Description: Thermal models of the proposed repository at Yucca Mountain, Nevada, suggest that rocks near the proposed host rock will experience elevated temperatures for at least 1000 yrs. In order to assess the effects of elevated temperatures on zeolites clinoptilolite and mordenite were investigated using a combination of high-temperature X-ray powder diffraction, thermogravimetric and differential scanning calorimetric analysis, and long-term heating experiments. 13 refs., 7 figs.
Date: April 1, 1990
Creator: Bish, D.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Three-dimensional modeling of unsaturated flow in the vicinity of proposed exploratory shaft facilities at Yucca Mountain, Nevada

Description: This report describes the results of a study to investigate the influence of proposed exploratory shafts on the moisture distribution within unsaturated, fractured rock at Yucca Mountain, Nevada. The long-term effects of exploratory shafts at Yucca Mountain are important in the estimation of potential waste migration and fate, while short-term effects may be important in the planning and interpretation of tests performed at the site. The PORFLO-3 computer code was used for simulation of moistur… more
Date: April 1, 1992
Creator: Rockhold, M.L.; Sagar, B. & Connelly, M.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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G-Tunnel Pressurized Slot-Testing Preparations; Yucca Mountain Site Characterization Project

Description: Designers and analysts of radioactive waste repositories must be able to predict the mechanical behavior of the host rock. Sandia National laboratories elected to conduct a development program on pressurized slot testing and featured (1) development of an improved method to cut slots using a chain saw with diamond-tipped cutters, (2) measurements useful for determining in situ stresses normal to slots, (3) measurements applicable for determining the in situ modulus of deformation parallel to a … more
Date: April 1, 1992
Creator: Zimmerman, R. M.; Sifre-Soto, C.; Mann, K. L.; Bellman, R. A. Jr.; Luker, S. & Dodds, D. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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