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TheU-Tube: A Novel System for Acquiring Borehole Fluid Samplesfrom a Deep Geologic CO2 Sequestration Experiment

Description: A novel system has been deployed to obtain geochemical samples of water and gas, at in situ pressure, during a geologic CO2 sequestration experiment conducted in the Frio brine aquifer in Liberty County, Texas. Project goals required high-frequency recovery of representative and uncontaminated aliquots of a rapidly changing two-phase (supercritical CO2-brine) fluid from 1.5 km depth. The datasets collected, using both the liquid and gas portions of the downhole samples, provide insights into th… more
Date: March 17, 2005
Creator: Freifeld, Barry M.; Trautz, Robert C.; Kharaka, Yousif K.; Phelps, Tommy J.; Myer, Larry R.; Hovorka, Susan D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The low cost of geological assessment for underground CO2 storage: Policy and economic implications

Description: The costs for carbon dioxide (CO{sub 2}) capture and storage (CCS) in geologic formations is estimated to be $6-75/t CO{sub 2}. In the absence of a mandate to reduce greenhouse gas emissions or some other significant incentive for CCS deployment, this cost effectively limits CCS technology deployment to small niche markets and stymies the potential for further technological development through learning-by-doing until these disincentives for the free venting of CO{sub 2} are in place. By far, th… more
Date: January 31, 2005
Creator: Friedmann, S J; Dooley, J; Held, H & Edenhofer, O
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final Scientific Report, Integrated Seismic Event Detection and Location by Advanced Array Processing

Description: In the field of nuclear explosion monitoring, it has become a priority to detect, locate, and identify seismic events down to increasingly small magnitudes. The consideration of smaller seismic events has implications for a reliable monitoring regime. Firstly, the number of events to be considered increases greatly; an exponential increase in naturally occurring seismicity is compounded by large numbers of seismic signals generated by human activity. Secondly, the signals from smaller events be… more
Date: January 30, 2007
Creator: Kvaerna, T.; Gibbons, S. J.; Ringdal, F & Harris, D. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High resolution trace element and isotopic imaging of microbial systems by NanoSIMS

Description: The NanoSIMS 50 is the state of the art in high spatial resolution secondary ion mass spectrometry (SIMS), combining unprecedented spatial resolution (as good as 50 nm) with ultra-high sensitivity (minimum detection limit of {approx}200 atoms). The NanoSIMS has an array of detectors, enabling simultaneous collection of 5 species originating from the same sputtered volume of a sample. The primary ion beam (Cs{sup +} or O{sup -}) can be scanned across the sample to produce quantitative secondary … more
Date: September 8, 2005
Creator: Weber, P K; Fallon, S J; Pett-Ridge, J; Ghosal, S; Ramon, C E & Hutcheon, I D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final Report: DoE SBIR Phase 2 Low-Cost Small Diameter NMR Technologies for In-Situ Subsurface Characterization and Monitoring

Description: In this Phase 2 SBIR program, Vista Clara successfully developed and field-tested small diameter NNR logging tools for subsurface characterization and monitoring. This effort involved the design and development surface electronics, a winch with 470ft cable, and three interchangeable downhole probes: a 3.5â diameter borehole NMR probe, a 1.67â diameter borehole NMR probe, and a 2.5â diameter NMR probe that can be deployed using a Geoprobe direct push machine. The 3.5â probe was tested extens… more
Date: September 3, 2010
Creator: Walsh, David Oliver
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solid phase evolution in the Biosphere 2 hillslope experiment as predicted by modeling of hydrologic and geochemical fluxes

Description: A reactive transport geochemical modeling study was conducted to help predict the mineral transformations occurring over a ten year time-scale that are expected to impact soil hydraulic properties in the Biosphere 2 (B2) synthetic hillslope experiment. The modeling sought to predict the rate and extent of weathering of a granular basalt (selected for hillslope construction) as a function of climatic drivers, and to assess the feedback effects of such weathering processes on the hydraulic proper… more
Date: July 15, 2009
Creator: Dontsova, K.; Steefel, C.I.; Desilets, S.; Thompson, A. & Chorover, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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STRUCTURAL HETEROGENEITIES AND PALEO FLUID FLOW IN AN ANALOG SANDSTONE RESERVOIR 2001-2004

Description: Fractures and faults are brittle structural heterogeneities that can act both as conduits and barriers with respect to fluid flow in rock. This range in the hydraulic effects of fractures and faults greatly complicates the challenges faced by geoscientists working on important problems: from groundwater aquifer and hydrocarbon reservoir management, to subsurface contaminant fate and transport, to underground nuclear waste isolation, to the subsurface sequestration of CO2 produced during fossil-… more
Date: February 22, 2005
Creator: Pollard, David & Aydin, Atilla
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Estimating large-scale fractured rock properties from radon data collected in a ventilated tunnel

Description: To address regulatory issues regarding worker safety, radon gas concentrations have been monitored as part of the operation of a deep tunnel excavated from a highly fractured tuff formation. The objective of this study was to examine the potential use of the radon data to estimate large-scale formation properties of fractured rock. An iTOUGH2 model was developed to predict radon concentrations for prescribed ventilation rates. The numerical model was used (1) to estimate the permeability and po… more
Date: May 12, 2003
Creator: Unger, Andre; Finsterle, Stefan & Bodvarsson, Gudmundur S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Near-Surface CO2 Monitoring And Analysis To Detect Hidden Geothermal Systems

Description: ''Hidden'' geothermal systems are systems devoid of obvious surface hydrothermal manifestations. Emissions of moderate-to-low solubility gases may be one of the primary near-surface signals from these systems. We investigate the potential for CO2 detection and monitoring below and above ground in the near-surface environment as an approach to exploration targeting hidden geothermal systems. We focus on CO2 because it is the dominant noncondensible gas species in most geothermal systems and has … more
Date: January 19, 2005
Creator: Lewicki, Jennifer L. & Oldenburg, Curtis M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Control of biologically Active Degradation Zones By Vertical Heterogeneity : Applications In Fractured Media

Description: The key objective of this research was to determine the distribution of biologically active contaminant degradation zones in a fractured, subsurface medium with respect to vertical heterogeneities. Our expectation was that hydrogeological properties would determine the size, diversity, and activities of microbial communities in fractured basalt by controlling the fluxes and concentrations of aqueous constituents upon which these communities depend. We expected that microorganisms would be more … more
Date: 2001
Creator: Colwell, F. S.; Smith, R.; Fredrickson, J. K.; Reysenbach, A.-L.; Mckinley, J. P. & Onstott, T. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Numerical study of the THM effects on the near-field safety of ahypothetical nuclear waste repository - BMT1 of the DECOVALEX IIIproject. Part 3: Effects of THM coupling in sparsely fracturedrocks

Description: BENCHPAR project, the impact of thermal-hydrological-mechanical (THM) couplings on the performance of a bentonite-back-filled nuclear waste repository in near-field crystalline rocks is evaluated in a Bench-Mark Test problem (BMT1) and the results are presented in a series of three companion papers in this issue. This is the third paper with focus on the effects of THM processes at a repository located in a sparsely fractured rock. Several independent coupled THM analyses presented in this pape… more
Date: September 9, 2004
Creator: Rutqvist, J.; Chijimatsu, M.; Jing, L.; Millard, A.; Nguyen,T. S.; Rejeb, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calcite Precipitation and Trace Metal Partitioning in Groundwater and the Vadose Zone: Remediation of Strontium-90 and Other Divalent Metals and Radionuclides in Arid Western Environments

Description: Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. Demonstrating in situ immobilization of these contaminants in vadose zones or groundwater plumes is a cost-effective remediation strategy. However, the implementation of in situ remediation requires definition of the mechanism that controls sequestration of the contaminants. One such mechanism for metals and radionuclides is co-precipitation of these… more
Date: July 19, 2000
Creator: Smith, Robert W.; Colwell, F. S.; Ingram, Jani C.; Ferris, F. Grant & Reysenbach, Anna-Louise
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Department of Energy quarterly technical report

Description: The objective is to test the concept that the growth faults in Eugene Island Block 330 (EI-330 field) are conduits through which producing reservoirs are charged and that enhanced production can be developed by producing directly from the fault zone. The site, operated by Penzoil, is located in 250 feet of water and the productive depth intervals include 4000 to 9000 feet. The field demonstration will be accomplished by drilling and production testing of growth fault systems associated with the… more
Date: April 15, 1995
Creator: Anderson, R. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influences of Flow Transients and Porous Medium Heterogeneity on Colloid-Associated Contaminants Transport in the Vadose Zone

Description: During the past year (June 2003 to June 2004), work at Yale has centered on investigating the influences of porewater pH, flow transients, and the presence of natural organic matter (NOM) on the deposition and mobilization of clay colloids (kaolinite and illite) within columns packed with unsaturated porous media. The experiments on pH and flow-transient effects were described in our First-Term Progress Report (which covered the initial 18 months of the study) and will not be repeated here. Mor… more
Date: June 15, 2003
Creator: Saiers, James E. & Ryan, Joseph
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Calcite Precipitation and Trace Metal Partitioning in Groundwater and the Vadose Zone: Remediation of Strontium-90 and Other Divalent Metals and Radionuclides in Arid Western Environments

Description: Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. Demonstrating in situ immobilization of these contaminants in vadose zones or groundwater plumes is a cost-effective remediation strategy. However, the implementation of in situ remediation requires definition of the mechanism that controls sequestration of the contaminants. One such mechanism for metals and radionuclides is co-precipitation of these… more
Date: August 9, 2001
Creator: Smith, Robert W.; Colwell, F. S.; Ingram, Jani C.; Ferris, F. Grant & Reysenbach, Anna-Louise
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis and evaluation of interwell seismic logging techniques for reservoir characterization. [Quarterly report], April 1--June 30, 1992

Description: The objective of this three-year research program is to investigate interwell seismic logging techniques for indirectly interpreting oil and gas reservoir geology and pore fluid permeability. This work involves a balanced study of advanced theoretical and numerical modeling of seismic waves transmitted between pairs of reservoir wells combined with experimental data acquisition and processing of measurements at controlled sites as well as in full-scale reservoirs. This reservoir probing concept… more
Date: December 31, 1992
Creator: Parra, J. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geological aspects of the nuclear waste disposal problem

Description: For the successful solution of the high-level waste (HLW) problem in Russia one must take into account such factors as the existence of the great volume of accumulated HLW, the large size and variety of geological conditions in the country, and the difficult economic conditions. The most efficient method of HLW disposal consists in the maximum use of protective capacities of the geological environment and in using inexpensive natural minerals for engineered barrier construction. In this paper, … more
Date: June 1, 1994
Creator: Laverov, N.P.; Omelianenko, B.L. & Velichkin, V.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Carbon isotopic evidence for biodegradation of organic contaminants in the shallow vadose zone of the radioactive waste management complex

Description: Waste material buried in drums in the shallow subsurface at the Radioactive Waste Management Facility (RWMC) of the Idaho National Engineering and Environmental Laboratory (INEEL) contained significant amounts of organic compounds including lubricating oils and chlorinated solvents. CO{sub 2} concentrations in pore gas samples from monitoring wells in the vicinity of the disposal pits are 3 to 5 times higher than the concentrations in nearby background wells. The stable carbon isotope ratios ({… more
Date: September 4, 2003
Creator: Conrad, Mark E. & DePaolo, Donald J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characterization of porosity in support of mechanical property analysis

Description: Previous laboratory investigations of tuff have shown that porosity has a dominant, general effect on mechanical properties. As a result, it is very important for the interpretation of mechanical property data that porosity is measured on each sample tested. Porosity alone, however, does not address all of the issues important to mechanical behavior. Variability in size and distribution of pore space produces significantly different mechanical properties. A nondestructive technique for characte… more
Date: December 31, 1992
Creator: Price, R. H.; Martin, R. J., III & Boyd, P. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Isotopic studies of Yucca Mountain soil fluids and carbonate pedogenesis

Description: Secondary carbonates occurring within the soils, faults, and subsurface fractures of Yucca Mountain contain some of the best available records of paleoclimate and palehydrology for the potential radioactive waste repository site. This article discusses conceptual and analytical advances being made with regard to the interpretation of stable isotope data from pedogenic carbonates, specifically related to the {sup 13}C content of soil CO{sub 2}, CaCO{sub 3}, precipitation mechanisms, and isotopic… more
Date: December 31, 1994
Creator: McConnaughey, T. A.; Whelan, J. F.; Wickland, K. P. & Moscati, R. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SURFSCAN: Program to operate a LASER profilometer. Yucca Mountain Site Characterization Project

Description: This paper is written to document the SURFSCAN program. A large section of the code is devoted to error recovery. The heavy emphasis on error recovery allows unattended operation for extended periods. By combining error recovery with the use of control files, SURFSCAN has been operated for periods of several days with no operator intervention. At this time, the Surface Profilometer is a useful and productive tool in the Rock Mechanics Laboratory at Sandia National Laboratories/New Mexico. In th… more
Date: September 1, 1995
Creator: Hardy, R.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The effect of rock fragments on the hydraulic properties of soils

Description: Many soils contain rock fragments the sizes of which are much larger than the average pore size of the sieved soil. Due to the fact that these fragments are often fairly large in relation to the soil testing apparatus, it is common to remove them before performing hydrologic tests on the soil. The question then arises as to whether or not there is a simple way to correct the laboratory-measured values to account for the fragments, so as to arrive at property values that can apply to the soil in… more
Date: April 1, 1995
Creator: Zimmerman, R.W. & Bodvarsson, G.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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