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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

Regional characterization of Western China

Description: Geological, geophysical, and seismic data are being assembled and organized into a knowledge base for Western China as part of the CTBT Research and Development regional characterization effort. We have begun our analysis using data from the station WMQ of the Chinese Digital Seismic Network (CDSN). Regional seismograms are being analyzed to construct travel time curves, velocity models, attenuation characteristics, and to quantify regional propagation effects such as phase blockages. Using locations from the USGS Preliminary Determination of Epicenters (PDE) we have identified Pn, Pg, Sn, and Lg phases, constructed travel time curves, and estimated apparent velocities using linear regression. Surface wave group velocities will be measured and inverted for regional structure. Preliminary noise spectra for WMQ have been obtained from the IRIS DMC. Chinese seismicity catalogs from the USGS and SSB are being used to identify and obtain seismic data (including mine seismicity) and information for lower magnitude events. We have identified the locations of nearly 500 mines in China for inclusion in the knowledge base. Future work will involve expanding the data collection and analysis efforts to a larger region using data from additional CDSN, IRIS and portable stations.
Date: September 1, 1995
Creator: Randall, G.E.; Weaver, T.A.; Hartse, H.E.; Taylor, S.R.; Warren, R.G. & Cogbill, A.H.
Partner: UNT Libraries Government Documents Department

Results of Electrical Resistivity and Electrical Induction Measurements at Abana Mine, Quebec, Canada: Explanation of Some Factors Associated with Induction Method

Description: Technical paper issued by the Bureau of Mines over studies conducted on electrical resistivity at the Abana Mine in Quebec. The methods used, and results of the studies are discussed. This paper includes tables, maps, and illustrations.
Date: 1931
Creator: Potter, E. Vernon & Lee, F. W.
Partner: UNT Libraries Government Documents Department


Description: Airborne electromagnetic (AEM) surveys were flown during fiscal year (FY) 2008 within the 600 Area in an attempt to characterize the underlying subsurface and to aid in the closure and remediation design study goals for the 200-PO-1 Groundwater Operable Unit (OU). The rationale for using the AEM surveys was that airborne surveys can cover large areas rapidly at relatively low costs with minimal cultural impact, and observed geo-electrical anomalies could be correlated with important subsurface geologic and hydrogeologic features. Initial interpretation of the AEM surveys indicated a tenuous correlation with the underlying geology, from which several anomalous zones likely associated with channels/erosional features incised into the Ringold units were identified near the River Corridor. Preliminary modeling resulted in a slightly improved correlation but revealed that more information was required to constrain the modeling (SGW-39674, Airborne Electromagnetic Survey Report, 200-PO-1 Groundwater Operable Unit, 600 Area, Hanford Site). Both time-and frequency domain AEM surveys were collected with the densest coverage occurring adjacent to the Columbia River Corridor. Time domain surveys targeted deeper subsurface features (e.g., top-of-basalt) and were acquired using the HeliGEOTEM{reg_sign} system along north-south flight lines with a nominal 400 m (1,312 ft) spacing. The frequency domain RESOLVE system acquired electromagnetic (EM) data along tighter spaced (100 m [328 ft] and 200 m [656 ft]) north-south profiles in the eastern fifth of the 200-PO-1 Groundwater OU (immediately adjacent to the River Corridor). The overall goal of this study is to provide further quantification of the AEM survey results, using ground based geophysical methods, and to link results to the underlying geology and/or hydrogeology. Specific goals of this project are as follows: (1) Test ground based geophysical techniques for the efficacy in delineating underlying geology; (2) Use ground measurements to refine interpretations of AEM data; and (3) Improve the calibration and correlation ...
Date: December 2, 2010
Partner: UNT Libraries Government Documents Department

Corrective Action Investigation Plan for Corrective Action Unit 555: Septic Systems Nevada Test Site, Nevada, Rev. No.: 0 with Errata

Description: This Corrective Action Investigation Plan (CAIP) contains project-specific information including facility descriptions, environmental sample collection objectives, and criteria for conducting site investigation activities at Corrective Action Unit (CAU) 555: Septic Systems, Nevada Test Site (NTS), Nevada. This CAIP has been developed in accordance with the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996) that was agreed to by the State of Nevada, the U.S. Department of Energy (DOE), and the U.S. Department of Defense. Corrective Action Unit 555 is located in Areas 1, 3 and 6 of the NTS, which is approximately 65 miles (mi) northwest of Las Vegas, Nevada, and is comprised of the five corrective action sites (CASs) shown on Figure 1-1 and listed below: (1) CAS 01-59-01, Area 1 Camp Septic System; (2) CAS 03-59-03, Core Handling Building Septic System; (3) CAS 06-20-05, Birdwell Dry Well; (4) CAS 06-59-01, Birdwell Septic System; and (5) CAS 06-59-02, National Cementers Septic System. An FFACO modification was approved on December 14, 2005, to include CAS 06-20-05, Birdwell Dry Well, as part of the scope of CAU 555. The work scope was expanded in this document to include the investigation of CAS 06-20-05. The Corrective Action Investigation (CAI) will include field inspections, radiological surveys, geophysical surveys, sampling of environmental media, analysis of samples, and assessment of investigation results, where appropriate. Data will be obtained to support corrective action alternative evaluations and waste management decisions. The CASs in CAU 555 are being investigated because hazardous and/or radioactive constituents may be present in concentrations that could potentially pose a threat to human health and the environment. Existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend corrective action alternatives for the CASs. Additional information will be generated by conducting a CAI before the evaluation and selection of ...
Date: December 1, 2005
Creator: Pastor, Laura
Partner: UNT Libraries Government Documents Department

Test definitions for the evaluation of infrasound sensors.

Description: Most test methodologies referenced in this Test Definition and Test Procedures were designed by Sandia specifically for geophysical instrumentation evaluation. When appropriate, test instrumentation calibration is traceable to the National Institute for Standards Technology (NIST). The objectives are to evaluate the overall technical performance of the infrasound sensor. The results of these evaluations can be compared to the manufacturer's specifications and any relevant application requirements or specifications.
Date: July 1, 2007
Creator: Kromer, Richard Paul (R.P. Kromer Consulting, Albuquerque, NM); Hart, Darren M. & Harris, James Mark
Partner: UNT Libraries Government Documents Department

Archaeological Analysis of Submerged Sites on the Gulf of Mexico Outer Continental Shelf

Description: This is a study on the Bureau of Ocean Energy Management's (BOEM's) investigation of six shipwrecks on the Outer Continental Shelf (OCS) of the Gulf of Mexico in order to verify the shipwrecks existed and provide information on them.
Date: August 2013
Creator: Evans, Amanda M.; Keith, Matthew E.; Voisin, Erin E.; Hesp, Patrick A.; Cook, Gregory D.; Allison, Mead A. et al.
Partner: UNT Libraries Government Documents Department

Post-Injection Geophysical Evaluation of the Winding Ridge Site CRADA 98-F012, Final Report

Description: Acid mine drainage (AMD) from underground mines is a major environmental problem. The disposal of coal combustion by-products (CCB) is also a major national problem due to the large volumes produced annually and the economics associated with transportation and environmentally safe disposal. The concept of returning large volumes of the CCB to their point of origin, underground mines, and using the typically alkaline and pozzolanic attributes of the waste material for the remediation of AMD has been researched rather diligently during the past few years by various federal and state agencies and universities. As the result, the State of Maryland initiated a full-scale demonstration of this concept in a small, 5-acre, unmapped underground mine located near Friendsville, MD. Through a cooperative agreement between the State of Maryland and the U.S. Department of Energy, several geophysical techniques were evaluated as potential tools for the post-injection evaluation of the underground mine site. Three non-intrusive geophysical surveys, two electromagnetic (EM) techniques and magnetometry, were conducted over the Frazee Mine, which is located on Winding Ridge near Friendsville, MD. The EM surveys were conducted to locate ground water in both mine void and overburden. The presence of magnetite, which is naturally inherent to CCB'S due to the combustion process and essentially transparent in sedimentary rock, provided the reason for using magnetometry to locate the final resting place of the CCB grout.
Date: September 16, 1998
Creator: Lyons, Connie; Current, Richard & Ackman, Terry
Partner: UNT Libraries Government Documents Department

Joint inversion of geophysical data for site characterization and restoration monitoring

Description: The purpose of this project is to develop a computer code for joint inversion of seismic and electrical data, to improve underground imaging for site characterization and remediation monitoring. The computer code developed in this project will invert geophysical data to obtain direct estimates of porosity and saturation underground, rather than inverting for seismic velocity and electrical resistivity or other geophysical properties. This is intended to be a significant improvement in the state-of-the-art of underground imaging, since interpretation of data collected at a contaminated site would become much less subjective. Potential users include DOE scientists and engineers responsible for characterizing contaminated sites and monitoring remediation of contaminated sites. In this three-year project, we use a multi-phase approach consisting of theoretical and numerical code development, laboratory investigations, testing on available laboratory and borehole geophysics data sets, and a controlled field experiment, to develop practical tools for joint electrical and seismic data interpretation.
Date: May 28, 1998
Creator: Berge, P. A.
Partner: UNT Libraries Government Documents Department

Paleoclimatic Drilling at Washoe Lake, November 1991 to March 1993. Final report

Description: A lacustrine sediment sequence in Washoe Lake in western Nevada was drilled in 1992 for paleoclimatic and paleohydrologic studies. In late June, 1991, the lake completely dried up for the first time since 1933-34 and only the second time in recorded history, offering a rare opportunity to obtain long continuous sections from a quasi-permanent lake in a climatically sensitive region. The lake is nominally 31 km{sup 2} in size and averages 3-4 m in depth. During the Pleistocene, the water depth was on the order of 13-17 m, and the lake occupied a much more extensive area. Geologic studies of the basin sides suggest that lacustrine sediments have been deposited for at least the last 2.5 my.
Date: December 1, 1998
Creator: Winkler, P.
Partner: UNT Libraries Government Documents Department

Environmental geophysics at Kings Creek Disposal Site and 30th Street Landfill, Aberdeen Proving Ground, Maryland

Description: Geophysical studies on the Bush River Peninsula in the Edgewood Area of Aberdeen Proving Ground, Maryland, delineate landfill areas and provide diagnostic signatures of the hydrogeologic framework and possible contaminant pathways. These studies indicate that, during the Pleistocene Epoch, alternating stands of high and low seal levels resulted in a complex pattern of shallow channel-fill deposits in the Kings Creek area. Ground-penetrating radar studies reveal a paleochannel greater than 50 ft deep, with a thalweg trending offshore in a southwest direction into Kings Creek. Onshore, the ground-penetrating radar data indicate a 35-ft-deep branch to the main channel, trending to the north-northwest directly beneath the 30th Street Landfill. Other branches are suspected to meet the offshore paleochannel in the wetlands south and east of the 30th Street Landfill. This paleochannel depositional system is environmentally significant because it may control the shallow groundwater flow regime beneath the site. Electromagnetic surveys have delineated the pre-fill lowland area currently occupied by the 30th Street Landfill. Magnetic and conductive anomalies outline surficial and buried debris throughout the study area. On the basis of geophysical data, large-scale dumping has not occurred north of the Kings Creek Disposal Site or east of the 30th Street Landfill.
Date: January 1, 1995
Creator: Davies, B.E.; Miller, S.F.; McGinnis, L.D.; Daudt, C.R.; Thompson, M.D.; Stefanov, J.E. et al.
Partner: UNT Libraries Government Documents Department

Crosshole EM for oil field characterization and EOR monitoring: Field examples

Description: Crosshole and surface-to-borehole electromagnetic (EM) imaging is applied to reservoir characterization and steam flood monitoring in a central California oil field. Steam was injected into three stacked, eastward-dipping, unconsolidated oil sands within the upper 200 in. The steam plume is expected to develop as an ellipse aligned with the regional northwest-southeast strike. EM measurements were made from two flberglass-cased observation wells straddling the steam injector on a northeast-southwest profile. Field data were collected before the initiation of a steam drive to map the distribution of the oil sands and then six months after the steam was injected to monitor the progress of the steam chest. Resisitivity images derived from the EM data collected before steam injection clearly delineate the distribution and dipping structure on the target oil sands. Difference images from data collected before and after steam flooding indicate that the steam chest has developed only in the deeper oil sands, and it has preferentially migrated eastward. Surface-to-borehole measurements were useful in mapping the distribution of the major oil sands, but they were insensitive to resisitivity changes in the early stages of the steam flood.
Date: September 1, 1994
Creator: Wilt, M.; Schenkel, C.; Torres-Verdin, C.; Lee, Ki Ha & Tseng, Hung-Wen
Partner: UNT Libraries Government Documents Department

Improved Oil Recovery in Fluvial Dominated Deltaic Reservoirs of Kansas Near Term

Description: The objective of this project is to address waterflood problems of the type found in Morrow sandstone reservoirs in southwestern Kansas and Cherokee Group reservoirs in southeastern Kansas. Two demonstration sites operated by different independent oil operators are involved in this project. The Stewart Field is located in Finney County, Kansas and is operated by North American Resources Company. The Nelson Lease is located in Allen County, Kansas, in the N.E. Savonburg Field and is operated by James E. Russell Petroleum, Inc. General topics to be addressed are (1) reservoir management and performance evaluation, (2) waterflood optimization, and (3) the demonstration of recovery processes involving off-the-shelf technologies which can be used to enhance waterflood recovery, increase reserves, and reduce the abandonment rate of these reservoir types. In the Stewart Project, the reservoir management portion of the project conducted during Budget Period I involved performance evaluation. This included (1) reservoir characterization and the development of a reservoir database, (2) volumetric analysis to evaluate production performance, (3) reservoir modeling, (4) laboratory work, (5) identification of operational problems, (6) identification of unrecovered mobile oil and estimation of recovery factors, and (7) identification of the most efficient and economical recovery process. To accomplish these objectives the initial budget period was subdivided into three major tasks. The tasks were (1) geological and engineering analysis, (2) laboratory testing, and (3) unitization. Due to the presence of different operators within the field, it was necessary to unitize the field in order to demonstrate a field-wide improved recovery process. This work was completed and the project moved into Budget Period 2. Budget Period 2 objectives consisted of the design, construction, and operation of a field-wide waterflood utilizing state-of-the-art, off-the-shelf technologies in an attempt to optimize secondary oil recovery. To accomplish these objectives the second budget period was subdivided ...
Date: April 15, 1997
Creator: Green, D.W.; Willhlte, C.P.; Walton, A.; Schoeling, L.; Reynolds, R.; Michnick, M. et al.
Partner: UNT Libraries Government Documents Department

Description of the US Geological Survey`s slug-test and borehole geophysical-logging work at the Hallam Nuclear Facility. July to November 1994

Description: Four aquifer slug-tests were performed in two observation wells 1B and 4C at Hallam Nuclear Facility, Nebraska. Well 1B responded more rapidly than 4C. Borehole geophysics data were collected in observation wells 1B, 4C, B-4, B-8, and B-10 on November 3.
Date: December 1, 1994
Partner: UNT Libraries Government Documents Department

History of geophysical studies at the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico

Description: A variety of geophysical methods including the spectrum of seismic, electrical, electromagnetic and potential field techniques have supported characterization, monitoring and experimental studies at the Waste Isolation Pilot Plant (WIPP). The geophysical studies have provided significant understanding of the nature of site deformation, tectonics and stability. Geophysical methods have delineated possible brine reservoirs beneath the underground facility and have defined the disturbed rock zone that forms around underground excavations. The role of geophysics in the WIPP project has evolved with the project. The early uses were for site characterization to satisfy site selection criteria or factors. As the regulatory framework for WIPP grew since 1980, the geophysics program supported experimental and field programs such as Salado hydrogeology and underground room systems and excavations. In summary, the major types of issues that geophysical studies addressed for WIPP are: Site Characterization; Castile Brine Reservoirs; Rustler/Dewey Lake Hydrogeology; Salado Hydrogeology; and Excavation Effects. The nature of geophysics programs for WIPP has been to support investigation rather than being the principal investigation itself. The geophysics program has been used to define conceptual models (e.g., the Disturbed Rock Zone-DRZ) or to test conceptual models (e.g., high transmissivity zones in the Rustler Formation). The geophysics program primarily supported larger characterization and experimental programs. Funding was not available for the complete documentation and interpretation. Therefore, a great deal of the geophysics survey information resides in contractor reports.
Date: March 5, 1997
Creator: Borns, D.J.
Partner: UNT Libraries Government Documents Department

Bibliography, geophysical data locations, and well core listings for the Mississippi Interior Salt Basin

Description: To date, comprehensive basin analysis and petroleum system modeling studies have not been performed on any of the basins in the northeastern Gulf of Mexico. Of these basins, the Mississippi Interior Salt Basin has been selected for study because it is the most petroliferous basin in the northeastern Gulf of Mexico, small- and medium-size companies are drilling the majority of the exploration wells. These companies do not have the resources to perform basin analysis or petroleum system modeling research studies nor do they have the resources to undertake elaborate information searches through the volumes of publicly available data at the universities, geological surveys, and regulatory agencies in the region. The Advanced Geologic Basin Analysis Program of the US Department of Energy provides an avenue for studying and evaluating sedimentary basins. This program is designed to improve the efficiency of the discovery of the nation`s remaining undiscovered oil resources by providing improved access to information available in the public domain and by increasing the amount of public information on domestic basins. This report provides the information obtained from Year 1 of this study of the Mississippi Interior Salt Basin. The work during Year 1 focused on inventorying the data files and records of the major information repositories in the northeastern Gulf of Mexico and making these inventories easily accessible in an electronic format.
Date: May 1, 1998
Partner: UNT Libraries Government Documents Department

Case studies of geophysical search methods relevant to the continuation phase of an on-Site inspection

Description: Part II of the Protocol of the Comprehensive Test Ban Treaty prescribes the use of geophysical methods such as active seismic surveys and electrical conductivity measurements to search for and locate underground anomalies, including cavities and rubble zones, during the continuation phase of an on-site inspection. In this paper the application of spontaneous potential, magnetotelluric, active seismic, and gas sampling studies at the US Nevada Test Site associated with underground nuclear explosions will be described and discussed in the context of on-site inspections. Spontaneous potential and E-field ratio telluric methods were found to be effective in some geologic settings but not in others. An example of gas sampling is shown for which radiogenic gas was detected several years after detonation. The case study of the application of active seismic methods illustrates limitations imposed by the use of relatively simple systems in the field. Detection of a deeply-buried cavity or rubble zone will be difficult; results from the application of only a single method will likely be ambiguous. Best results will come from the synthesis of results from a number of widely-varying methods.
Date: April 20, 1999
Creator: Sweeney, J J
Partner: UNT Libraries Government Documents Department

Structural Model of the Basement in the Central Savannah River Area, South Carolina and Georgia

Description: Interpretation of several generations of seismic reflection data and potential field data suggests the presence of several crustal blocks within the basement beneath the Coastal Plain in the Central Savannah River Area (CSRA). The seismic reflection and refraction data include a grid of profiles that capture shallow and deep reflection events and traverse the Savannah River Site and vicinity. Potential field data includes aeromagnetic, ground magnetic surveys, reconnaissance and detailed gravity surveys. Subsurface data from recovered core are used to constrain the model.Interpretation of these data characteristically indicate a southeast dipping basement surface with some minor highs and lows suggesting an erosional pre-Cretaceous unconformity. This surface is interrupted by several basement faults, most of which offset only early Cretaceous sedimentary horizons overlying the erosional surface. The oldest fault is perhaps late Paleozoic because it is truncated at the basement/Coastal Plain interface. This fault is related in timing and mechanism to the underlying Augusta fault. The youngest faults deform Coastal Plain sediments of at least Priabonian age (40-36.6 Ma). One of these young faults is the Pen Branch faults, identified as the southeast dipping master fault for the Triassic Dunbarton basin. All the Cenozoic faults are probably related in time and mechanism to the nearby, well studied Belair fault.The study area thus contains a set of structures evolved from the Alleghanian orogeny through Mesozoic extension to Cenozoic readjustment of the crust. There is a metamorphosed crystalline terrane with several reflector/fault packages, a reactivated Triassic basin, a mafic terrane separating the Dunbarton basin from the large South Georgia basin to the southeast, and an overprint of reverse faults, some reactivated, and some newly formed.
Date: March 1992
Creator: Stephenson, D. & Stieve, A.
Partner: UNT Libraries Government Documents Department

Environmental geophysics: Building E3640 Decommissioning, Aberdeen Proving Ground, Maryland. Interim progress report

Description: Building E3640 is a potentially contaminated site in the Edgewood area of Aberdeen Proving Ground. Noninvasive geophysical survey techniques, including magnetics, EM-31, EM-61, and ground-penetrating radar, were used as part of a sampling and monitoring program prior to decommissioning and dismantling of the building. Complex and large-amplitude anomalies caused by aboveground metal in this area obscure many smaller features produced by subsurface sources. No underground storage tanks were found in the areas surveyed. Major anomalies produced by subsurface sources include the following: EM-61 and EM-31 lineaments caused by a water line extending north from the south fence; a broad positive magnetic anomaly caused by magnetic fill north of the material and drum storage area and northeast of E3640; a 30-ft-wide band of EM-31 anomalies extending from the front gate to the southeast comer of E3640 and a coincident EM-61 anomaly produced by buried utilities; ground-penetrating radar images along three lines extending from a sump at the northeast comer of E3640 to the eastern fence; and EM-61, EM-31, and magnetic anomalies caused by overhead and underground pipes extending south from the north fence. Smaller, unidentified, localized anomalies observed throughout the survey area are also described in this report.
Date: January 1995
Creator: McGinnis, L. D.; Miller, S. F.; Borden, H. M.; Benson, M. A.; Thompson, M. D.; Padar, C. A. et al.
Partner: UNT Libraries Government Documents Department

Geophysical Surveys of a Known Karst Feature, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Description: Geophysical data were acquired at a site on the Oak Ridge Reservation, Tennessee to determine the characteristics of a mud-filled void and to evaluate the effectiveness of a suite of geophysical methods at the site. Methods that were used included microgravity, electrical resistivity, and seismic refraction. Both microgravity and resistivity were able to detect the void as well as overlying structural features. The seismic data provide bedrock depth control for the other two methods, and show other effects that are caused by the void.
Date: November 14, 1999
Creator: Carpenter, P.J.; Carr, B.J.; Doll, W.E.; Kaufmann, R.D. & Nyquist, J.E.
Partner: UNT Libraries Government Documents Department

Neural network identifications of spectral signatures

Description: We have investigated the application of neural nets to the determination of fundamental leaf canopy parameters from synthetic spectra. We describe some preliminary runs in which we separately determine leaf chemistry, leaf structure, leaf area index, and soil characteristics, and then we perform a simultaneous determination of all these parameters in a single neural network run with synthetic six-band Landsat data. We find that neural nets offer considerable promise in the determination of fundamental parameters of agricultural and environmental interest from broad-band multispectral data. The determination of the quantities of interest is frequently performed with accuracies of 5% or better, though as expected, the accuracy of determination in any one parameter depends to some extent on the value of other parameters, most importantly the leaf area index. Soil characterization, for example, is best done at low lai, while leaf chemistry is most reliably done at high lai. We believe that these techniques, particularly when implemented in fast parallel hardware and mounted directly on remote sensing platforms, will be useful for various agricultural and environmental applications.
Date: February 1, 1996
Creator: Gisler, G. & Borel, C.
Partner: UNT Libraries Government Documents Department