424 Matching Results

Search Results

Advanced search parameters have been applied.

Preliminary Efforts to Couple TETRAD with Geophysics Models

Description: The Geothermal Program at the Idaho National Engineering and Environmental Laboratory is enhancing our reservoir simulation capabilities by writing new subroutines with TETRAD that write necessary files for use with SAIC's geophysics models, including DC Resistivity, SP, and microgravity. This is part of long-term efforts to develop reservoir models that take advantage of various observations that are - or can be - made on both existing fields or during exploration efforts. These new routines will be made available to the TETRAD user community in 2002 through the next release of TETRAD 2002.
Date: January 1, 2002
Creator: Shook, George Michael; Renner, Joel Lawrence & Bloomfield, Kevin Kit
Partner: UNT Libraries Government Documents Department

Fall 2007 American Geophysical Union Meeting Student Travel Support for Environmental Nanomaterials Session (#B35) (December 10-14, 2007)

Description: The purpose of award no. DE-FG02-08ER15925 was to fund travel for students to present at the Fall 2007 American Geophysical Meeting. This was done successfully, and five students (Bin Xie, Qiaona Hu, Katie Schreiner, Daria Kibanova, and Frank-Andreas Weber) gave excellent oral and poster presentations at the meeting. Provided are the conference abstracts for their presentations.
Date: October 1, 2007
Creator: Michael F. Hochella, Jr.
Partner: UNT Libraries Government Documents Department

Borehole Data-Collection Methods Applicable for the Regional Observation and Monitor Well Program, Southwest Florida Water Management District

Description: From introduction: This report presents some borehole data-collection methods that can be used during the drilling of ROMP or other wells where data collection is a prime objective. Hydraulic, water-quality, and geophysical data-collection methods applicable to the hydrogeology of west-central Florida are emphasized.
Date: September 1981
Creator: Hickey, John J.
Partner: UNT Libraries Government Documents Department

Improved characterization through joint hydrogeophysical inversion: Examples of three different approaches

Description: With the increasing application of geophysical methods to hydrogeological problems, approaches for obtaining quantitative estimates of hydrogeological parameters using geophysical data are in great demand. A common approach to hydrogeological parameter estimation using geophysical and hydrogeological data is to first invert the geophysical data using a geophysical inversion procedure, and subsequently use the resulting estimates together with available hydrogeological information to estimate a hydrogeological parameter field. This approach does not allow us to constrain the geophysical inversion by hydrogeological data and prior information, and thus decreases our ability to make valid estimates of the hydrogeological parameter field. Furthermore, it is difficult to quantify the uncertainty in the corresponding estimates and to validate the assumptions made. They are developing alternative approaches that allow for the joint inversion of all available hydrological and geophysical data. In this presentation, they consider three studies and draw various conclusions, such as on the potential benefits of estimating the petrophysical relationships within the inversion framework and of constraining the geophysical estimates on geophysical, as well as hydrogeological data.
Date: July 1, 2004
Creator: Linde, Niklas; Chen, Jinsong; Kowalsky, Michael; Finsterle,Stefan; Rubin, Yoram & Hubbard, Susan
Partner: UNT Libraries Government Documents Department

Assessing non-uniqueness: An algebraic approach

Description: Geophysical inverse problems are endowed with a rich mathematical structure. When discretized, most differential and integral equations of interest are algebraic (polynomial) in form. Techniques from algebraic geometry and computational algebra provide a means to address questions of existence and uniqueness for both linear and non-linear inverse problem. In a sense, the methods extend ideas which have proven fruitful in treating linear inverse problems.
Date: September 16, 2002
Creator: Vasco, Don W.
Partner: UNT Libraries Government Documents Department

Summaries of FY 1995 geosciences research

Description: The summaries in this document, prepared by the investigators, describe the scope of the individual programs. The Geosciences Research Program includes research in geophysics, geochemistry, resource evaluation, solar-terrestrial interactions, and their subdivisions including earth dynamics, properties of earth materials, rock mechanics, underground imaging, rock-fluid interactions, continental scientific drilling, geochemical transport, solar/atmospheric physics, and modeling, with emphasis on the interdisciplinary areas. All such research is related either direct or indirect to the Department of Energy`s long-range technological needs.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

Seismic Determination of Reservoir Heterogeneity: Application to the Characterization of Heavy Oil Reservoirs

Description: The objective of the project was to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study focused on West Coalinga Field in California. The project initially attempted to build reservoir models based on different geologic and geophysical data independently using different tools, then to compare the results, and ultimately to integrate them all. We learned, however, that this strategy was impractical. The different data and tools need to be integrated from the beginning because they are all interrelated. This report describes a new approach to geostatistical modeling and presents an integration of geology and geophysics to explain the formation of the complex Coalinga reservoir.
Date: February 1, 2005
Creator: Imhof, Matthias G. & Castle, James W.
Partner: UNT Libraries Government Documents Department

Geological and Geophysical Survey of Fluorspar Areas in Hardin County, Illinois

Description: From abstract: Pt 1. The present work seems to confirm the genetic theory previously published, namely that [Illinois Cave in Rock] deposits were formed by ascending solutions. These solutions probably followed minor fissures that connected below with larger fissures, which in turn probably connected with a major fault zone. It is believed that where such minor fissures extended upward only to the shale or other impervious cap rock, or were greatly reduced in size where they penetrated such beds, the solutions spread laterally along the contact and along the limestone beds beneath it and replaced the limestone. Pt 2. This report is a presentation of the results of an electrical-resistivity survey conducted in the fluorspar-bearing areas of Hardin County, Ill., principally during the field seasons of 1934 and 1935.
Date: 1944
Creator: Currier, Louis W.; Wagner, Oscar Emil, Jr. & Hubbert, M. King
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 estimates 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 imaging the subsurface. The overall objective of our research, defined at the start of this project, was to advance the usefulness of radar methods (ground-based and borehole) as a means of characterizing water content in the vadose zone. We have met this objective by providing research results that can be used to (1) improve the accuracy of water content estimates from radar measurements; (2) provide estimates of the potential error in water content estimates from radar measurements; (3) improve the clarity of radar images; (4) develop large-scale models of the subsurface ''architecture'' using radar images; (5) develop ways of quantifying the spatial heterogeneity of the subsurface through analysis of radar images. We have also been able to identify the critical areas where more research is needed in order to be able to use radar methods most effectively as an accurate means of subsurface characterization.
Date: December 28, 2003
Creator: Knight, Rosemary
Partner: UNT Libraries Government Documents Department

Geochemical Controls on Nuclear Magnetic Resonance Measurements

Description: OAK-B135 Our research objectives are to determine, through an extensive set of laboratory experiments, the effect of the specific mineralogic form of iron and the effect of the distribution of iron on proton nuclear magnetic resonance (NMR) relaxation mechanisms. In the first nine months of this project, we have refined the experimental procedures to be used in the acquisition of the laboratory NMR data; have ordered, and conducted preliminary measurements on, the sand samples to be used in the experimental work; and have revised and completed the theoretical model to use in this project. Over the next year, our focus will be on completing the first phase of the experimental work where the form and distribution of the iron in the sands in varied.
Date: November 11, 2003
Creator: Knight, Rosemary; Prasad, Manika & Keating, Kristina
Partner: UNT Libraries Government Documents Department

A Strategy for Monitoring of Geologic Sequestration of CO2

Description: Monitoring of geologic sequestration projects will require the measurement of many different parameters and processes at many different locations at the surface and in the subsurface. The greatest need for technology development is for monitoring of processes in the subsurface in the region between wells. The approach to fitting this need is to build upon decades of experience in use of geophysics in the oil and gas industry. These methods can be optimized for CO2 monitoring, and customized and extended in order to meet the need for cost-effective methods applicable to saline disposal sites, coal bed methane sites, as well as oil and gas reservoir sequestration sites. The strategy for development of cost-effective methods follows a three step iterative process of sensitivity analysis using numerical and experimental techniques, field testing at a range of scale in different formations, and analysis and integration of complimentary types of data.
Date: April 17, 2000
Creator: Myer, Larry R.
Partner: UNT Libraries Government Documents Department

3DTOM, Three-Dimensional Geophysical Tomography

Description: Abstract: 3DTOM is a DOS-compatible computer program developed by the Mines U.S. Bureau of for three-dimensional tomographic imaging of the subsurface at mine sites. The program uses the simultaneous iterative reconstruction technique (SIRT) to invert travel- time data and produce maps of wave velocity, or to invert amplitude data and generate maps of wave attenuation coefficients. Either seismic (compressional and/or shear) or electromagnetic (e.g., radio or radar) wave data may be used. Ray tracing in 3DTOM uses several different methods, including ray bending, network theory, and a combination of these. User-defined constraints are important in reducing the mathematical nonuniqueness of inversions based on limited data. 3DTOM permits the use of hard constraints, or soft constraints based on fuzzy logic, to allow for uncertainty in the constraints. Reliable subsurface images are useful in many different mine-related problems, including void detection, fracture detection, fluid monitoring, and qualitative stress evaluation.
Date: 1996
Creator: Jackson, M. J. & Tweeton, Daryl R.
Partner: UNT Libraries Government Documents Department

Interim Report on the Location of Nonsaline Uraniferous Waters Suitable for Ion-Exchange Process

Description: From introduction: The Trace Elements Section Washington Laboratory had developed the methods used in anticipation of handling an increased volume of water analyses as this preliminary project is expanded into a full-scale investigation. The efforts of these groups were coordinated by the Trace Elements Planning and Coordination Office.
Date: November 1952
Creator: Aberdeen, E. J.; White, W. F.; Sherwood, A. M.; Bruce, F. L. & Ferguson, D. E.
Partner: UNT Libraries Government Documents Department

Re-Inversion of Surface Electrical Resistivity Tomography Data from the Hanford Site B-Complex

Description: This report documents the three-dimensional (3D) inversion results of surface electrical resistivity tomography (ERT) data collected over the Hanford Site B-Complex. The data were collected in order to image the subsurface distribution of electrically conductive vadose zone contamination resulting from both planned releases of contamination into subsurface infiltration galleries (cribs, trenches, and tile fields), as well as unplanned releases from the B, BX, and BY tank farms and/or associated facilities. Electrically conductive contaminants are those which increase the ionic strength of pore fluids compared to native conditions, which comprise most types of solutes released into the subsurface B-Complex. The ERT data were collected and originally inverted as described in detail in report RPP-34690 Rev 0., 2007, which readers should refer to for a detailed description of data collection and waste disposal history. Although the ERT imaging results presented in that report successfully delineated the footprint of vadose zone contamination in areas outside of the tank farms, imaging resolution was not optimized due to the inability of available inversion codes to optimally process the massive ERT data set collected at the site. Recognizing these limitations and the potential for enhanced ERT characterization and time-lapse imaging at contaminated sites, a joint effort was initiated in 2007 by the U.S. Department of Energy – Office of Science (DOE-SC), with later support by the Office of Environmental Management (DOE-EM), and the U.S. Department of Defense (DOD), to develop a high-performance distributed memory parallel 3D ERT inversion code capable of optimally processing large ERT data sets. The culmination of this effort was the development of E4D (Johnson et al., 2010,2012) In 2012, under the Deep Vadose Zone Applied Field Research Initiative (DVZ-AFRI), the U.S. Department of Energy – Richland Operations Office (DOE-RL) and CH2M Hill Plateau Remediation Company (CHPRC) commissioned an effort for the Pacific ...
Date: May 1, 2013
Creator: Johnson, Timothy C. & Wellman, Dawn M.
Partner: UNT Libraries Government Documents Department

Final Report for the grant "Applied Geometry" (DOE DE-FG02-04ER25657)

Description: The primary purpose of this 3-year DOE-funded research effort, now completed, was to develop consistent, theoretical foundations of computations on discrete geometry, to realize the promise of predictive and scalable management of large geometric datasets as handled routinely in applied sciences. Geometry (be it simple 3D shapes or higher dimensional manifolds) is indeed a central and challenging issue from the modeling and computational perspective in several sciences such as mechanics, biology, molecular dynamics, geophysics, as well as engineering. From digital maps of our world, virtual car crash simulation, predictive animation of carbon nano-tubes, to trajectory design of space missions, knowing how to process and animate digital geometry is key in many cross-disciplinary research areas.
Date: May 20, 2009
Creator: Desbrun, Prof. Mathieu
Partner: UNT Libraries Government Documents Department