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Crosswell seismic and electromagnetic monitoring of CO2sequestration

Description: The quantitative estimation of changes in water saturation (S{sub W}) and effective pressure (P), in terms of changes in compressional and shear impedance, is becoming routine in the interpretations of time-lapse surface seismic data. However, when the number of reservoir constituents increases to include in situ gas and injected CO{sub 2}, there are too many parameters to be determined from seismic velocities or impedances alone. In such situations, the incorporation of electromagnetic (EM) images showing the change in electrical conductivity ({sigma}) provides essential independent information. The purpose of this study was to demonstrate a methodology for jointly interpreting crosswell seismic and EM data, in conjunction with detailed constitutive relations between geophysical and reservoir parameters, to quantitatively predict changes in P, S{sub W}, CO{sub 2} gas saturation (S{sub CO2}), CO{sub 2} gas/oil ratio (R{sub CO{sub 2}}), hydrocarbon gas saturation (S{sub g}), and hydrocarbon gas/oil ration (R{sub g}) in a reservoir undergoing CO{sub 2} flood.
Date: July 30, 2002
Creator: Hoversten, G. Michael; Gritto, Roland; Daley, Thomas M.; Majer,Ernest L. & Myer, Larry R.
Partner: UNT Libraries Government Documents Department

Effects of uncertainty in rock-physics models on reservoirparameter estimation using marine seismic AVA and CSEM data

Description: This study investigates the effects of uncertainty inrockphysics models on estimates of reservoir parameters from jointinversion of seismic AVA and CSEMdata. The reservoir parameters arerelated to electrical resistivity using Archie's law, and to seismicvelocity and density using the Xu-White model. To account for errors inthe rock-physics models, we use two methods to handle uncertainty: (1)the model outputs are random functions with modes or means given by themodel predictions, and (2) the parameters of the models are themselvesrandom variables. Using a stochastic framework and Markov Chain MonteCarlo methods, we obtain estimates of reservoir parameters as well as ofthe uncertainty in the estimates. Synthetic case studies show thatuncertainties in both rock-physics models and their associated parameterscan have significant effects on estimates of reservoir parameters. Ourmethod provides a means of quantifying how the uncertainty in theestimated reservoir parameters increases with increasing uncertainty inthe rock-physics model and in the model parameters. We find that in theexample we present, the estimation of water saturation is relatively lessaffected than is the estimation of clay content and porosity.
Date: April 9, 2007
Creator: Chen, Jinsong & Dickens, Thomas
Partner: UNT Libraries Government Documents Department

Water Imbibition into Rock as Affected by Sample Shape, Pore, Conductivity, and Antecedent Water Content

Description: Infiltration is often presumed to follow Philip's equation, I = st{sup 1/2}, where I is cumulative infiltration, s is sorptivity, and t is time. This form of the equation is appropriate for short times, and/or for negligible gravitational effects. For a uniform soil, this equation describes a plot of log(mass imbibed) versus log(time), with a slope (imbibition exponent) of 1/2. The equation has also been applied to low-porosity rocks, where the extremely small pores render gravitational forces negligible. Experiments recently performed on a wide variety of rocks produced imbibition exponents from 0.2 to 0.5. Many rock types showed initial imbibition proceeding as I {approx} t{sup 1/4}, then later switched to ''normal'' (t{sup 1/2}) behavior. The distance to the wetting front that corresponds to this cross-over behavior was found to be related to the sample shape: tall thin samples are more likely to exhibit the exponent 1/4, and to cross over to 1/2-type behavior later, while short, squat samples are less likely to display the 1/4-type behavior at all. Additionally, the exponents are sensitive to antecedent water content, with initially wetter samples having smaller values. In this study, we present the experimental data, and provide a consistent and physically-based explanation using percolation theory. The analogy between imbibition and diffusion is used to model imbibition into samples with low pore connectivity, with the exponents and their crossover behavior emerging from a random walk process. All laboratory phenomena--different exponents, crossover behavior, and effects of sample shape and antecedent water content--are reproduced by the model, with similar patterns across experiment and simulation. We conclude both that diffusion is a useful and powerful conceptual model for understanding imbibition, and also that imbibition experiments, being simpler than diffusion measurements, can be used to examine diffusive behavior in rock.
Date: August 29, 2005
Creator: Ewing, R.P.
Partner: UNT Libraries Government Documents Department

Hydraulic properties of adsorbed water films in unsaturated porous media

Description: Adsorbed water films strongly influence residual water saturations and hydraulic conductivities in porous media at low saturations. Hydraulic properties of adsorbed water films in unsaturated porous media were investigated through combining Langmuir's film model with scaling analysis, without use of any adjustable parameters. Diffuse double layer influences are predicted to be important through the strong dependence of adsorbed water film thickness (f) on matric potential ({Psi}) and ion charge (z). Film thickness, film velocity, and unsaturated hydraulic conductivity are predicted to vary with z{sup -1}, z{sup -2}, and z{sup -3}, respectively. In monodisperse granular media, the characteristic grain size ({lambda}) controls film hydraulics through {lambda}{sup -1} scaling of (1) the perimeter length per unit cross sectional area over which films occur, (2) the critical matric potential ({Psi}{sub c}) below which films control flow, and (3) the magnitude of the unsaturated hydraulic conductivity when {Psi} < {Psi}{sub c}. While it is recognized that finer textured sediments have higher unsaturated hydraulic conductivities than coarser sands at intermediate {Psi}, the {lambda}{sup -1} scaling of hydraulic conductivity predicted here extends this understanding to very low saturations where all pores are drained. Extremely low unsaturated hydraulic conductivities are predicted under adsorbed film-controlled conditions (generally < 0.1 mm y{sup -1}). On flat surfaces, the film hydraulic diffusivity is shown to be constant (invariant with respect to {Psi}).
Date: March 1, 2009
Creator: Tokunaga, Tetsu K.
Partner: UNT Libraries Government Documents Department

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

Description: This project seeks to improve the basic understanding of colloid and colloid-facilitated transport of Cs in the vadose zone. The specific objectives are: (1) Determine the structure, composition, and surface charge characteristics of colloidal particles formed under conditions similar to those occurring during leakage of waste typical of Hanford tank supernatants into soils and sediments surrounding the tanks. (2) Characterize the mutual interactions between colloids, contaminant, and soil matrix in batch experiments under various ionic strength and pH conditions. We will investigate the nature of the solid-liquid interactions and the kinetics of the reactions. (3) Evaluate mobility of colloids through soil under different degrees of water saturation and solution chemistry (ionic strength and pH). (4) Determine the potential of colloids to act as carriers to transport the contaminant through the vadose zone and verify the results through comparison with field samples collected under leaking tanks. Results of this project will help to understand the fundamental mechanisms of Cs transport under the leaking Hanford tanks, and thus contribute to the long-term clean-up strategies at the Hanford site.
Date: June 1, 2001
Creator: Flury, Markus; Harsh, James B.; Zachara, John M. & Jin, Yan
Partner: UNT Libraries Government Documents Department

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

Description: This project seeks to improve the basic understanding of the role of colloids in facilitating the transport of contaminants in the vadose zone. We focus on three major thrusts: (1) thermodynamic stability and mobility of colloids formed by reactions of sediments with highly alkaline tank waste solutions, (2) colloid-contaminant interactions, and (3) in situ colloid mobilization and colloid-facilitated contaminant transport occurring in both contaminated and uncontaminated Hanford sediments. The specific objectives that will be addressed are: (1) Determine the liability and thermodynamic stability of colloidal materials, which form after reacting Hanford sediments with simulated Hanford Tank Waste. (2) Determine the potential of Hanford sediments for in situ mobilization of colloids for different types of sediments and different leaching scenarios. (3) Characterize the interactions between initially-formed colloids, their dissolution/alteration products, and native colloidal particles with contaminants in batch experiments under various ionic strength and pH conditions. (4) Evaluate colloid-facilitated radionuclide transport through sediments under different degrees of water saturation in packed and undisturbed sediment columns. (5) Implement colloid-facilitated contaminant transport mechanisms and thermodynamic stability constants into a reactive chemical transport model, and verify model simulations with experimental transport data. Results of this project will help to understand the fundamental mechanisms of Cs transport under the leaking Hanford tanks, and thus contribute to the long-term clean-up strategies at the Hanford site.
Date: June 13, 2002
Creator: Flury, Markus; Harsh, James B.; Zachara, John M. & Lichtner, Peter C.
Partner: UNT Libraries Government Documents Department

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

Description: This project seeks to improve the basic understanding of colloid and colloid-facilitated transport of Cs in the vadose zone. The specific objectives are: (1) Determine the structure, composition, and surface charge characteristics of colloidal particles formed under conditions similar to those occurring during leakage of waste typical of Hanford tank supernatants into soils and sediments surrounding the tanks. (2) Characterize the mutual interactions between colloids, contaminant, and soil matrix in batch experiments under various ionic strength and pH conditions. We will investigate the nature of the solid-liquid interactions and the kinetics of the reactions. (3) Evaluate mobility of colloids through soil under different degrees of water saturation and solution chemistry (ionic strength and pH). (4) Determine the potential of colloids to act as carriers to transport the contaminant through the vadose zone and verify the results through comparison with field samples collected under leaking tanks. Results of this project will help to understand the fundamental mechanisms of Cs transport under the leaking Hanford tanks, and thus contribute to the long-term clean-up strategies at the Hanford site.
Date: June 1, 2002
Creator: Flury, Markus; Harsh, James B.; Zachara, John M. & Jin, Yan
Partner: UNT Libraries Government Documents Department

Direct Reservoir Parameter Estimation Using Joint Inversion ofMarine Seismic AVA&CSEM Data

Description: A new joint inversion algorithm to directly estimate reservoir parameters is described. This algorithm combines seismic amplitude versus angle (AVA) and marine controlled source electromagnetic (CSEM) data. The rock-properties model needed to link the geophysical parameters to the reservoir parameters is described. Errors in the rock-properties model parameters, measured in percent, introduce errors of comparable size in the joint inversion reservoir parameter estimates. Tests of the concept on synthetic one-dimensional models demonstrate improved fluid saturation and porosity estimates for joint AVA-CSEM data inversion (compared to AVA or CSEM inversion alone). Comparing inversions of AVA, CSEM, and joint AVA-CSEM data over the North Sea Troll field, at a location with well control, shows that the joint inversion produces estimated gas saturation, oil saturation and porosity that is closest (as measured by the RMS difference, L1 norm of the difference, and net over the interval) to the logged values whereas CSEM inversion provides the closest estimates of water saturation.
Date: January 12, 2005
Creator: Hoversten, G. Michael; Cassassuce, Florence; Gasperikova, Erika; Newman, Gregory A.; Rubin, Yoram; Zhangshuan, Hou et al.
Partner: UNT Libraries Government Documents Department

PETROPHYSICAL INVESTIGATION OF THE SECONDARY RECOVERY POTENTIAL IN THE CHERRY CANYON FORMATION NE LEA FIELD LEA COUNTY, NEW MEXICO

Description: Read and Stevens has proposed the evaluation of the waterflood potential from the Cherry Canyon formation in the NE Lea Field in lea County, New Mexico. Much of the development in this area is approaching primary recovery limitations; additional recovery of remaining oil reserves by waterflood needs to be evaluated. The Cherry Canyon formation is composed of fine grained sandstone, containing clay material which results in high water saturation, and also has the tendency to swell and reduce reservoir permeability--the ability of fluid to flow through the rock pores and fractures. There are also abundant organic materials that interfere with obtaining reliable well logs. These complications have limited oil in place calculations and identification of net pay zones, presenting a challenge to the planned waterflood. Core analysis of the Cherry Canyon should improve the understanding of existing well logs and possibly indicate secondary recovery measures, such as waterflood, to enhance field recovery. Lacking truly representative core to provide accurate analyses, Read and Stevens will obtain and preserve fresh core. The consulting firm of T. Scott Hickman and Associates will then collaborate on special core analyses and obtain additional well logs for a more detailed analysis of reservoir properties. The log interpretation will be compared to the core analysis results, and the entire collected data set will be used to assess the potential and economic viability of successfully waterflooding the identified oil zones. Successful results from the project will improve accuracy of log interpretation and establish a methodology for evaluating secondary recovery by waterflood.
Date: June 1, 2002
Creator: Hickman, T. Scott
Partner: UNT Libraries Government Documents Department

Seismic low-frequency effects from oil-saturated reservoir zones

Description: We consider the frequency dependence of seismic reflections from a thin (compared to the dominant wavelength), fluid saturated reservoir for the cases of oil and water saturation. Reflections from a thin, water or oil-saturated layer have increased amplitude and delayed travel time at low frequencies if compared with reflections from a gas-saturated layer. This effect was observed for both ultrasonic lab data and seismic field data. One set of field data revealed high correlation of low frequency processed image for two different production horizons represented by fractured shale and sandstone. Another set was processed for the purpose of contouring of oil/water contact, and reveal very good correlation with available well data. The frequency dependent amplitude and phase reflection properties can be used for detecting and monitoring thin liquid saturated layers.
Date: April 16, 2002
Creator: Goloshubin, Gennady M.; Korneev, Valeri A. & Vingalov, Vjacheslav M.
Partner: UNT Libraries Government Documents Department

The Use of Radar Methods to Determine Moisture Content in the Vadose Zone

Description: Water content is a critical parameter affecting both liquid-phase and vapor-phase contaminant transport in the vadose zone. This means that accurate estimate of in situ water content must be obtained in order to design for the appropriate handling or remediation of a contaminated region of the vadose zone. Traditional methods of sampling the subsurface by drilling and/or direct sampling are very time consuming, limited in terms of spatial coverage, and have the associated risk of contacting and increasing the size of the contaminated area. One solution is to use geophysical methods which can provide a high-resolution, non-invasive means of sampling or imagin the subsurface.
Date: December 28, 2003
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

Description: In Section 1 of this first report we will describe the work we are doing to collect and analyze rock physics data for the purpose of modeling seismic attenuation from other measurable quantities such as porosity, water saturation, clay content and net stress. This work and other empirical methods to be presented later, will form the basis for ''Q pseudo-well modeling'' that is a key part of this project. In Section 2 of this report, we will show the fundamentals of a new method to extract Q, dispersion, and attenuation from field seismic data. The method is called Gabor-Morlet time-frequency decomposition. This technique has a number of advantages including greater stability and better time resolution than spectral ratio methods.
Date: January 1, 2002
Creator: Walls, Joel; Taner, M.T.; Mavko, Gary & Dvorkin, Jack
Partner: UNT Libraries Government Documents Department

SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

Description: In fully-saturated rock and at ultrasonic frequencies, the microscopic squirt flow induced between the stiff and soft parts of the pore space by an elastic wave is responsible for velocity-frequency dispersion and attenuation. In the seismic frequency range, it is the macroscopic cross-flow between the stiffer and softer parts of the rock. We use the latter hypothesis to introduce simple approximate equations for velocity-frequency dispersion and attenuation in a fully water saturated reservoir. The equations are based on the assumption that in heterogeneous rock and at a very low frequency, the effective elastic modulus of the fully-saturated rock can be estimated by applying a fluid substitution procedure to the averaged (upscaled) dry frame whose effective porosity is the mean porosity and the effective elastic modulus is the Backus-average (geometric mean) of the individual dry-frame elastic moduli of parts of the rock. At a higher frequency, the effective elastic modulus of the saturated rock is the Backus-average of the individual fully-saturated-rock elastic moduli of parts of the rock. The difference between the effective elastic modulus calculated separately by these two methods determines the velocity-frequency dispersion. The corresponding attenuation is calculated from this dispersion by using (e.g.) the standard linear solid attenuation model.
Date: July 1, 2002
Creator: Walls, Joel; Taner, M.T.; Mavko, Gary & Dvorkin, Jack
Partner: UNT Libraries Government Documents Department

Colloid-Facilitated Transport of Radionuclides through the Vadose Zone

Description: This project seeks to improve the basic understanding of colloid and colloid- facilitated transport of Cs in the vadose zone. The specific objectives are: (1) Determine the structure, composition, and surface charge characteristics of colloidal particles formed under conditions similar to those occurring during leakage of waste typical of Hanford tank supernatants into soils and sediments surrounding the tanks. (2) Characterize the mutual interactions between colloids, contaminant, and soil matrix in batch experiments under various ionic strength and pH conditions. We will investigate the nature of the solid-liquid interactions and the kinetics of the reactions. (3) Evaluate mobility of colloids through soil under different degrees of water saturation and solution chemistry (ionic strength and pH). (4) Determine the potential of colloids to act as carriers to transport the contaminant through the vadose zone and verify the results through comparison with field samples collected under leaking tanks. Results of this project will help to understand the fundamental mechanisms of Cs transport under the leaking Hanford tanks, and thus contribute to the long-term clean-up strategies at the Hanford site.
Date: June 1, 2003
Creator: Flury, Markus; Harsh, James B. & Zachara, John M. Jin, Yan
Partner: UNT Libraries Government Documents Department

Geoscience/engineering characterization of the interwell environment in carbonate reservoirs based on outcrop analogs, Permian Basin, West Texas and New Mexico--waterflood performance analysis for the South Cowden Grayburg Reservoir, Ector County, Texas. Final report

Description: A reservoir engineering study was conducted of waterflood performance in the South Cowden field, an Upper Permian Grayburg reservoir on the Central Basin Platform in West Texas. The study was undertaken to understand the historically poor waterflood performance, evaluate three techniques for incorporating petrophysical measurements and geological interpretation into heterogeneous reservoir models, and identify issues in heterogeneity modeling and fluid-flow scaleup that require further research. The approach included analysis of relative permeability data, analysis of injection and production data, heterogeneity modeling, and waterflood simulation. The poor South Cowden waterflood recovery is due, in part, to completion of wells in only the top half of the formation. Recompletion of wells through the entire formation is estimated to improve recovery in ten years by 6 percent of the original oil in place in some areas of the field. A direct three-dimensional stochastic approach to heterogeneity modeling produced the best fit to waterflood performance and injectivity, but a more conventional model based on smooth mapping of layer-averaged properties was almost as good. The results reaffirm the importance of large-scale heterogeneities in waterflood modeling but demonstrate only a slight advantage for stochastic modeling at this scale. All the flow simulations required a reduction to the measured whole-core k{sub v}/k{sub h} to explain waterflood behavior, suggesting the presence of barriers to vertical flow not explicitly accounted for in any of the heterogeneity models. They also required modifications to the measured steady-state relative permeabilities, suggesting the importance of small-scale heterogeneities and scaleup. Vertical flow barriers, small-scale heterogeneity modeling, and relative permeability scaleup require additional research for waterflood performance prediction in reservoirs like South Cowden.
Date: May 1, 1997
Creator: Jennings, J.W. Jr.
Partner: UNT Libraries Government Documents Department

CO2 gas/oil ratio prediction in a multi-component reservoir bycombined seismic and electromagnetic imaging

Description: Crosswell seismic and electromagnetic data sets taken before and during CO2 flooding of an oil reservoir are inverted to produce crosswell images of the change in compressional velocity, shear velocity and electrical conductivity during a CO2 injection pilot study. A rock properties model is developed using measured log porosity, fluid saturations, pressure, temperature, bulk density, sonic velocity and electrical conductivity. The parameters of the rock properties model are found by an L1-norm simplex minimization of predicted and observed compressional velocity and density. A separate minimization using Archie's law provides parameters for modeling the relations between water saturation, porosity and the electrical conductivity. The rock properties model is used to generate relationships between changes in geophysical parameters and changes in reservoir parameters. The electrical conductivity changes are directly mapped to changes in water saturation. The estimated changes in water saturation are used with the observed changes in shear wave velocity to predict changes in reservoir pressure. The estimation of the spatial extent and amount of CO2 relies on first removing the effects of the water saturation and pressure changes from the observed compressional velocity changes, producing a residual compressional velocity change. The residual compressional velocity change is then interpreted in terms of increases in the CO2 /oil ratio. Resulting images of CO2/oil ratio show CO2 rich zones that are well correlated with the location of injection perforations with the size of these zones also correlating to the amount of injected CO2. The images produced by this process are better correlated to the location and amount of injected CO2 than are any of the individual images of change in geophysical parameters.
Date: August 28, 2002
Creator: Hoversten, G.M.; Gritto, Roland; Washbourne, John & Daley, Tom
Partner: UNT Libraries Government Documents Department

Fluid dynamic properties of phyolitic magmas, Mineral Mountains, Utah. Part 1: Volatile content and flow characteristics. Part II: Physical properties

Description: Part 1 describes rhyolites from southwestern Utah that display striking dissimilarities in morphology which are attributed to viscosity differences due to variations in water content. Temperature effects and fluorine concentrations are unable to account for the observed differences in morphology. Fluid dynamic calculations indicate that rhyolite flows of fluid aspect contained between 1 and 3% water upon eruption. More viscous domes contained less water which was expelled in pyroclastic eruptions preceding emplacement of the domal rhyolite magma.
Date: July 1, 1978
Creator: Nash, W.P. & Evans, S.H., Jr.
Partner: UNT Libraries Government Documents Department

Permeability of laboratory-formed methane-hydrate-bearing sand: Measurements and observations using x-ray computed tomography

Description: Methane hydrate was formed in two moist sands and a sand/silt mixture under a confining stress in an X-ray-transparent pressure vessel. Three initial water saturations were used to form three different methane-hydrate saturations in each medium. X-ray computed tomography (CT) was used to observe location-specific density changes caused by hydrate formation and flowing water. Gas-permeability measurements in each test for the dry, moist, frozen, and hydrate-bearing states are presented. As expected, the effective permeabilities (intrinsic permeability of the medium multiplied by the relative permeability) of the moist sands decreased with increasing moisture content. In a series of tests on a single sample, the effective permeability typically decreased as the pore space became more filled, in the order of dry, moist, frozen, and hydrate-bearing. In each test, water was flowed through the hydrate-bearing medium and we observed the location-specific changes in water saturation using CT scanning. We compared our data to a number of models, and our relative permeability data compare most favorably with models in which hydrate occupies the pore bodies rather than the pore throats. Inverse modeling (using the data collected from the tests) will be performed to extend the relative permeability measurements.
Date: September 15, 2010
Creator: Kneafsey, T. J.; Seol, Y.; Gupta, A. & Tomutsa, L.
Partner: UNT Libraries Government Documents Department

West Hackberry Tertiary Project. Technical progress report, October 1--December 31, 1996

Description: The West Hackberry Tertiary Project is a field test of the concept that air injection can be combined with the Double Displacement Process to produce a tertiary recovery process that is both low cost and economic at current oil prices. The Double Displacement Process is the gas displacement of a water invaded oil column for the purpose of recovering tertiary oil by gravity drainage. In reservoirs with pronounced bed dip such as those found in West hackberry and other Gulf Coast salt dome fields, reservoir performance has shown that gravity drainage recoveries average 80% to 90% of the original oil in place while waterdrive recoveries average 50% to 60% of the original oil in place. The target for tertiary oil recovery in the Double Displacement Process is the incremental oil between the 50% to 60% waterdrive recoveries and the 80% to 90% gravity drainage recoveries. In previous field tests, the Double Displacement Process has proven successful in generating tertiary oil recovery. The use of air injection in this process combines the benefits of air`s low cost and universal accessibility with the potential for accelerated oil recovery from the combustion process. If successful, this project will demonstrate that utilizing air injection in the Double Displacement Process will result in an economically viable tertiary process in reservoirs (such as Gulf Coast salt dome reservoirs) where other tertiary processes are presently uneconomic.
Date: January 14, 1997
Creator: Gillham, T.; Cerveny, B. & Turek, E.
Partner: UNT Libraries Government Documents Department

Electrical resistivity monitoring of the single heater test in Yucca Mountain

Description: Of the several thermal, mechanical and hydrological measurements being used to monitor the rockmass response in the Single Heater Test, electrical resistance tomography (ERT) is being used to monitor the movement of liquid water with a special interest in the movement of condensate out of the system. Images of resistivity change were calculated using data collected before, during and after the heating episode. This report will concentrate on the results obtained after heating ceased; previous reports discuss the results obtained during the heating phase. The changes recovered show a region of increasing resistivity approximately centered around the heater as the rock mass cooled. The size of this region grows with time and the resistivity increases become stronger. The increases in resistivity are caused by both temperature and saturation changes. The Waxman Smits model has been used to calculate rock saturation after accounting for temperature effects. The saturation estimates suggest that during the heating phase, a region of drying forms around the heater. During the cooling phase, the dry region has remained relatively stable. Wetter rock regions which developed below the heater during the heating phase, are slowly becoming smaller in size during the cooling phase. The last set of images indicate that some rewetting of the dry zone may be occurring. The accuracy of the saturation estimates depends on several factors that are only partly understood.
Date: October 1, 1997
Creator: Ramirez, A.
Partner: UNT Libraries Government Documents Department

Analysis of hydraulic tests of the Culebra and Magenta Dolomites and Dewey Lake Redbeds conducted at the Waste Isolation Pilot Plant Site

Description: This report presents interpretations of hydraulic tests conducted at 15 well locations in the vicinity of the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico between 1980 and 1996. The WIPP is a US Department of Energy (DOE) facility to demonstrate safe disposal of transuranic wastes arising form the nation`s defense programs. The WIPP repository lies within bedded halite of the Salado Formation, 2,155 ft below ground surface. The tests reported herein were, with two exceptions, conducted in the Culebra Dolomite member of the Rustler Formation, which overlies the Salado Formation. The remaining tests were conducted in the Magenta Member of the Rustler and in the overlying formation, the Dewey Lake Redbeds. This report completes the documentation of hydraulic-test interpretations used as input to the WIPP Compliance Certification Application (US DOE, 1996).
Date: September 1, 1998
Creator: Beauheim, R.L. & Ruskauff, G.J.
Partner: UNT Libraries Government Documents Department