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[Photograph of Mineral Wells, Texas 1881]
Photograph of Mineral Wells, Texas, taken in 1881. (Please observe that the picture carries a copyright by A. F. Weaver.)
Date:
1991
Creator:
Bevan, James
Object Type:
Photograph
System:
The Portal to Texas History
The drilling of a horizontal well in a mature oil field
This report documents the drilling of a medium radius horizontal well in the Bartlesville Sand of the Flatrock Field, Osage County, Oklahoma by Rougeot Oil and Gas Corporation (Rougeot) of Sperry, Oklahoma. The report includes the rationale for selecting the particular site, the details of drilling the well, the production response, conclusions reached, and recommendations made for the future drilling of horizontal wells. 11 figs., 2 tabs.
Date:
January 1, 1991
Creator:
Rougeot, John E. & Lauterbach, Kurt A.
Object Type:
Report
System:
The UNT Digital Library
Mineral Resources of the Sleeping Giant Wilderness Study Area, Lewis and Clark County, Montana
From abstract: A mineral resource survey was conducted in 1987 by the U.S. Geological Survey and the U.S. Bureau of Mines to evaluate mineral resources (known) and mineral resource potential (undiscovered) of the Sleeping Giant Wilderness Study Area (MT-075-111) in Lewis and Clark County, Montana. The only economic resource in the study area is an inferred 1.35-million-ton reserve of decorative stone (slate); a small gold placer resource is subeconomic. A high resource potential for decorative slate exists directly adjacent to the area of identified slate resource and in the northeastern part of the study area. The rest of the study area has a low potential for decorative slate. The westernmost part of the study area has a moderate resource potential for copper and associated silver in strata-bound deposits in green beds and limestone; potential is low in the rest of the study area.
Date:
1991
Creator:
Tysdal, Russell G.; Reynolds, Mitchell W.; Carlson, Robert R.; Kleinkopf, M. D.; Rowan, L. C. & Peters, Thomas J.
Object Type:
Report
System:
The UNT Digital Library
Identification of the mineral phases responsible for cementation of Lurgi spent oil shale
The purpose of this study is to investigate the mineralogical character of the cements that are responsible for the increased strength of the spent oil shale. Several techniques to identify the nature of the cementing agents have been used in this study. X-ray diffraction was used to identify mineral dissolution and formation; scanning electron microscopy (SEM) was used to observe the cementing agents; energy dispersive X-ray analysis (EDXA) was used to provide information on the elemental composition of both the bulk material and the cementing agents; and differential thermal analyses and thermogravimetric analyses were used to document the presence of suspected minerals that may be involved in formation of the cementing material.
Date:
February 1, 1991
Creator:
Brown, M.; Huntington, G. & Brown, T.
Object Type:
Report
System:
The UNT Digital Library
Identification of the mineral phases responsible for cementation of Lurgi spent oil shale
The purpose of this study is to investigate the mineralogical character of the cements that are responsible for the increased strength of the spent oil shale. Several techniques to identify the nature of the cementing agents have been used in this study. X-ray diffraction was used to identify mineral dissolution and formation; scanning electron microscopy (SEM) was used to observe the cementing agents; energy dispersive X-ray analysis (EDXA) was used to provide information on the elemental composition of both the bulk material and the cementing agents; and differential thermal analyses and thermogravimetric analyses were used to document the presence of suspected minerals that may be involved in formation of the cementing material.
Date:
February 1, 1991
Creator:
Brown, M.; Huntington, G. & Brown, T.
Object Type:
Report
System:
The UNT Digital Library
A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1
This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The project has been conducted by Beckley College, Inc., and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center (METC). This section, Volume II, contains a detailed discussion of the methodology used and the geological and production information collected and analyzed for this study. A companion document, Volume 1, provides an overview of the program, technique and results of the study. In combination, Volumes I and II cover the completion of the research undertaken under Phase I of this DOE project, which included the identification of five high-potential sites for natural gas production on the Eccles Quadrangle, Raleigh County, West Virginia. Each of these sites was selected for its excellent potential for gas production from both relatively shallow coalbeds and the deeper, conventional reservoir formations.
Date:
May 1, 1991
Creator:
Overbey, W. K. Jr.; Reeves, T. K.; Salamy, S. P.; Locke, C. D.; Johnson, H. R.; Brunk, R. et al.
Object Type:
Report
System:
The UNT Digital Library
Characterizing hydraulically fractured reservoirs using induced microearthquakes
Hydraulic fracturing is a common method employed to increase the production of oil and gas fields. Recently, there has been increased interest in monitoring the microearthquakes induced by hydraulic fracturing as a means of obtaining data to characterize reservoir changeS induced by the injection. Two types of microearthquakes have been observed during hydraulic fracturing. Tensile events have been observed and modeled as the parting of the surfaces of a fracture. A majority of the events observed have been shear-slip events, where two sides of a fault plane slip parallel to each other but in opposite directions. The locations of the microearthquakes can be analyzed to determine regions where significant seismic energy was released, which presumably are regions where injected fluid penetrated into the rock along pre-existing fractures or zones of weakness. The spatial patterns in the locations can be analyzed to fine regions where events cluster along planes, which are interpreted to be the dominant fluid flow paths. Imaging methods can also be applied to the travel time and waveform data to obtain direct evidence for the locations of the fractures or fracture zones. 27 refs., 2 figs.
Date:
January 1, 1991
Creator:
Fehler, M.
Object Type:
Article
System:
The UNT Digital Library
Results of Phase 2 postburn drilling, coring, and logging: Rocky Mountain 1 Underground Coal Gasification Test, Hanna, Wyoming
The Rocky Mountain 1 (RM1) Underground Coal Gasification (UCG) site consisted of two different module configurations: the controlled retracting injection point (CRIP) and elongated linked well (ELW) configurations. The postburn coring of the RM1 UCG site was designed in two phases to fulfill seven objectives outlined in Western Research Institute's Annual Project Plan for 1989 (Western Research Institute 1989). The seven objectives were to (1) delineate the areal extent of the cavities, (2) identify the extent of roof collapse, (3) obtain samples of all major cavity rock types, (4) characterize outflow channels and cavity stratigraphy, (5) characterize the area near CRIP points and ignition points, (6) further define the structural geology of the site, and (7) identify the vertical positioning of the horizontal process wells within the coal seam. Phase 1 of the coring was completed during the summer of 1989 and served to partially accomplish all seven objectives. A detailed description of Phase 1 results was presented in a separate report (Lindblom et al. 1990). Phase 2, completed during the summer of 1990, was designed to complete the seven objectives; more specifically, to further define the areal extent and location of the cavities, to evaluate the outflow channels for …
Date:
February 1, 1991
Creator:
Oliver, R. L.; Lindblom, S. R. & Covell, J. R.
Object Type:
Report
System:
The UNT Digital Library
Mapping acoustic emissions from hydraulic fracture treatments using coherent array processing: Concept
Hydraulic fracturing is a widely-used well completion technique for enhancing the recovery of gas and oil in low-permeability formations. Hydraulic fracturing consists of pumping fluids into a well under high pressure (1000--5000 psi) to wedge-open and extend a fracture into the producing formation. The fracture acts as a conduit for gas and oil to flow back to the well, significantly increasing communication with larger volumes of the producing formation. A considerable amount of research has been conducted on the use of acoustic (microseismic) emission to delineate fracture growth. The use of transient signals to map the location of discrete sites of emission along fractures has been the focus of most research on methods for delineating fractures. These methods depend upon timing the arrival of compressional (P) or shear (S) waves from discrete fracturing events at one or more clamped geophones in the treatment well or in adjacent monitoring wells. Using a propagation model, the arrival times are used to estimate the distance from each sensor to the fracturing event. Coherent processing methods appear to have sufficient resolution in the 75 to 200 Hz band to delineate the extent of fractures induced by hydraulic fracturing. The medium velocity structure must be …
Date:
September 1, 1991
Creator:
Harris, D. B.; Sherwood, R. J.; Jarpe, S. P. & Harben, P. E.
Object Type:
Report
System:
The UNT Digital Library
Microbial enhanced waterflooding pilot project, Mink Unit, Delaware-Childers (OK) field
The first microbial-enhanced waterflood field project was initiated in October of 1986. The site selected for the project is in the Mink Unit of Delaware-Childers field in Nowata County, Oklahoma. The pilot area consists of four adjacent inverted five-spot patterns drilled on 5-acre spacing. There are 21 injection and 15 production wells on this pilot. Four of the 21 injection wells were treated with microbial formulation. Laboratory screening criteria were developed to evaluate microorganisms for this project. Several different microbial formulations were tested. Injectivity and microbial field survivability tests were conducted during the baseline period on two off-pattern wells, and a chemical tracer, fluorescein, was injected into the four injection wells during the baseline period. Methodologies for field applications of microorganisms in ongoing waterfloods were developed as a result of this project. Results from the field pilot showed that microorganisms could be injected into an ongoing waterflood without causing any problems in injectivity. Microbial treatment did improve oil production rate, and water/oil ratios for producing wells nearest the microbially treated injection wells continue to be more favorable than baseline values. 23 refs., 30 figs., 28 tabs.
Date:
August 1, 1991
Creator:
Bryant, R. S.; Burchfield, T. E.; Dennis, D. M. & Hitzman, D. O.
Object Type:
Report
System:
The UNT Digital Library
Imaging techniques applied to the study of fluids in porous media
A detailed understanding of rock structure and its influence on fluid entrapment, storage capacity, and flow behavior can improve the effective utilization and design of methods to increase the recovery of oil and gas from petroleum reservoirs. The dynamics of fluid flow and trapping phenomena in porous media was investigated. Miscible and immiscible displacement experiments in heterogeneous Berea and Shannon sandstone samples were monitored using X-ray computed tomography (CT scanning) to determine the effect of heterogeneities on fluid flow and trapping. The statistical analysis of pore and pore throat sizes in thin sections cut from these sandstone samples enabled the delineation of small-scale spatial distributions of porosity and permeability. Multiphase displacement experiments were conducted with micromodels constructed using thin slabs of the sandstones. The combination of the CT scanning, thin section, and micromodel techniques enables the investigation of how variations in pore characteristics influence fluid front advancement, fluid distributions, and fluid trapping. Plugs cut from the sandstone samples were investigated using high resolution nuclear magnetic resonance imaging permitting the visualization of oil, water or both within individual pores. The application of these insights will aid in the proper interpretation of relative permeability, capillary pressure, and electrical resistivity data obtained from …
Date:
January 1, 1991
Creator:
Tomutsa, L.; Doughty, D.; Mahmood, S.; Brinkmeyer, A. & Madden, M.P.
Object Type:
Report
System:
The UNT Digital Library
Proposed natural gas protection program for Naval Oil Shale Reserves Nos. 1 and 3, Garfield County, Colorado
As a result of US Department of Energy (DOE) monitoring activities, it was determined in 1983 that the potential existed for natural gas resources underlying the Naval Oil Shales Reserves Nos. 1 and 3 (NOSrs-1 3) to be drained by privately-owned gas wells that were being drilled along the Reserves borders. In 1985, DOE initiated a limited number of projects to protect the Government's interest in the gas resources by drilling its own offset production'' wells just inside the boundaries, and by formally sharing in the production, revenues and costs of private wells that are drilled near the boundaries ( communitize'' the privately-drilled wells). The scope of these protection efforts must be expanded. DOE is therefore proposing a Natural Gas Protection Program for NOSRs-1 3 which would be implemented over a five-year period that would encompass a total of 200 wells (including the wells drilled and/or communitized since 1985). Of these, 111 would be offset wells drilled by DOE on Government land inside the NOSRs' boundaries and would be owned either entirely by the Government or communitized with adjacent private land owners or lessees. The remainder would be wells drilled by private operators in an area one half-mile wide extending …
Date:
August 1, 1991
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Downhole material injector for lost circulation control
This invention is comprised of an apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.
Date:
January 1, 1991
Creator:
Glowka, David A.
Object Type:
Patent
System:
The UNT Digital Library
The Ahuachapan geothermal field, El Salvador: Exploitation model, performance predictions, economic analysis
The Earth Sciences Division of Lawrence Berkeley Laboratory (LBL) is conducting a reservoir evaluation study of the Ahuachapan geothermal field in El Salvador. This work is being performed in cooperation with the Comision Ejecutiva Hidroelectrica del Rio Lempa (CEL) and the Los Alamos National Laboratory (LANL) with funding from the US Agency for International Development (USAID). This report describes the work done during the second year of the study (FY89--90). The first year's report included (1) the development of geological and conceptual models of the field, (2) the evaluation of the reservoir's initial thermodynamic and chemical conditions and their changes during exploitation, (3) the evaluation of interference test data and the observed reservoir pressure decline and (4) the development of a natural state model for the field. In the present report the results of reservoir engineering studies to evaluate different production-injection scenarios for the Ahuachapan geothermal field are discussed. The purpose of the work was to evaluate possible reservoir management options to enhance as well as to maintain the productivity of the field during a 30-year period (1990--2020). The ultimate objective was to determine the feasibility of increasing the electrical power output at Ahuachapan from the current level of about …
Date:
May 1, 1991
Creator:
Ripperda, M.; Bodvarsson, G.S.; Lippmann, M.J.; Witherspoon, P.A. & Goranson, C.
Object Type:
Report
System:
The UNT Digital Library
{sup 40}Ar/{sup 39}Ar laser fusion and K-Ar ages from Lathrop Wells, Nevada, and Cima, California: The age of the latest volcanic activity in the Yucca Mountain area
K-Ar and {sup 40}Ar/{sup 39}Ar ages from the Lathrop Wells volcanic center, Nevada, and from the Cima volcanic field, California, indicate that the recently reported 20-ka age estimate for the Lathrop Wells volcanic center is incorrect. Instead, an age of 119 {plus_minus} 11 to 141 {plus_minus} 10 ka is indicated for the Lathrop Wells volcanic center. This age corrected is concordant with the ages determined by two independent isotopic geochronometric techniques and with the stratigraphy of surficial deposits in the Yucca Mountain region. In addition, paleomagnetic data and radiometric age data indicate only two volcanic events at the Lathrop Wells volcanic center that are probably closely linked in time, not as many as five as recently reported. 32 refs., 2 figs., 2 tabs.
Date:
May 1, 1991
Creator:
Turrin, B. D. & Champion, D. E.
Object Type:
Article
System:
The UNT Digital Library
Activities of the Oil Implementation Task Force, December 1990--February 1991; Contracts for field projects and supporting research on enhanced oil recovery, April--June 1990
The Oil Implementation Task Force was appointed to implement the US DOE's new oil research program directed toward increasing domestic oil production by expanded research on near- or mid-term enhanced oil recovery methods. An added priority is to preserve access to reservoirs that have the largest potential for oil recovery, but that are threatened by the large number of wells abandoned each year. This report describes the progress of research activities in the following areas: chemical flooding; gas displacement; thermal recovery; resource assessment; microbial technology; geoscience technology; and environmental technology. (CK)
Date:
March 1, 1991
Creator:
Tiedemann, H.A. (ed.) (USDOE Bartlesville Project Office, OK (USA))
Object Type:
Report
System:
The UNT Digital Library
Identification of environmental RD D needs
The objective of this project was to identify needs for environmental research development and demonstration projects that have the potential to improve the performance of oil and gas exploration, drilling, and production technologies for maximum recovery of domestic petroleum resources under optimal environmental and economic conditions. To achieve this objective several areas of work were addressed. The first task was to compile as much related data as possible. This was achieved by literature searches of a number of petroleum-related data bases. After acquiring sufficient background on environmental and economical areas that should be expanded, experts who are knowledgeable in these areas were contacted to further define specific issues. More than 33 identified areas were submitted to an in-house panel at NIPER to assure that the final environmental research demonstration and development needs that were selected to be expanded were unbiased and worthy of additional work. Specific subjects that were expanded include: (1) the Mechanical Integrity Testing of Injection Wells by Oxygen-Activation Log, (2) A More Rapid or Alternative Bioassay Test, (3) An Environmentally Safe Drilling Fluid Additive, (4) Bioremediation of Waste Pits, (5) A More Efficient Technology Transfer, (6) A Comprehensive Work Management Protocol, and (7) A Pollution Potential Prioritization …
Date:
September 1, 1991
Creator:
Crocker, M. E.; Madden, M. P. & Porter, R.
Object Type:
Report
System:
The UNT Digital Library
Microbial field pilot study
The objective of this project is to perform a microbially enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions or the reservoir and increase sweep efficiency. Injection of nutrient stimulates the growth and metabolism of reservoir bacteria, which produces beneficial products to enhance oil recovery. Sometimes, chemical treatments are used to clean or condition injection water. Such a chemical treatment has been initiated by Sullivan and Company at the Southeast Vassar Vertz Sand Unit. The unit injection water was treated with a mixture of water, methanol, isopropyl alcohol, and three proprietary chemicals. To determine if the chemicals would have an impact on the pilot, it was important to determine the effects of the chemical additives on the growth and metabolism of the bacteria from wells in this field. Two types of media were used: a mineral salts medium with molasses and nitrate, and this medium with 25 ppm of the treatment chemicals added. Samples were collected anaerobically from each of …
Date:
January 1, 1991
Creator:
Knapp, R.M.; McInerney, M.J. & Menzie, D.E.
Object Type:
Report
System:
The UNT Digital Library
[Assessment of effects of surfactants in a heavy oil reservoir]
During the past three months we have carefully negotiated a joint venture to implement a pilot for testing the two enhanced oil recovery processes developed at CLD Technology, Inc. The technical staff at CLD Technology, Inc. has decided to model the heavy oil reserve on the Cantleberry Lease, the Jasmin oil field in Kern County, California. Staff members have designed a new sand pack to represent one-eighth (1/8) of a one, ten-acre, five-spot well pattern that will represent the sands of the Cantleberry lease. All calculated parameters are listed in Table 1. The 3-dimensional scaled physical model design represents a typical Cantleberry steamflood pattern. The design of the model will allow the creation of zones identical to those in the Cantleberry lease which will represent the shale break between the Cantleberry A'' and B'' sands. The last 3-dimensional scaled physical model experiment, needed to design the pilot, is ready to go awaiting continuous funding from the DOE.
Date:
April 8, 1991
Creator:
Kostura, J.A.
Object Type:
Report
System:
The UNT Digital Library
Vertical pump turbine oil environmental evaluation
In Oregon low-temperature geothermal injection well construction, siting and receiving formations requires approval by the Water Resources Department (OWRD). In addition, the Oregon Department of Environmental Quality (ODEQ) has regulations concerning injection. Conversations with the OWRD and ODEQ representatives indicated they were very concerned about the potential for contamination of the geothermal (and cooler but hydraulically connected) aquifers by oils and grease. Their primary concern was over the practice of putting paraffin, motor oils and other hydrocarbons in downhole heat exchanger (DHE) wells to prevent corrosion. They also expressed considerable concern about the use of oil in production well pumps since the fluids pumped would be injected. Oregon (and Idaho) prohibit the use of oil-lubricated pumps for public water supplies except in certain situations where non-toxic food-grade lubricants are used. Since enclosed-lineshaft oil-lubricated pumps are the mainstay of direct-use pumping equipment, the potential for restricting their use became a concern to the Geo-Heat Center staff. An investigation into alternative pump lubrication schemes and development of rebuttals to potential restrictions was proposed and approved as a contract task. (SM)
Date:
April 1, 1991
Creator:
Culver, G.
Object Type:
Report
System:
The UNT Digital Library
Alternate Operating Strategies for Hot Dry Rock Geothermal Reservoirs
Flow testing and heat extraction experiments in prototype Hot Dry Rock (HDR) geothermal reservoirs have uncovered several challenges which must be addressed before commercialization of the technology is possible. Foremost among these is the creation of a reservoir which simultaneously possesses high permeability pathways and a large volume of fractured rock. The current concept of heat extraction -- a steady state circulation system with fluid pumping from the injection well to a single, low pressure production well -- may limit our ability to create heat extraction systems which meet these goals. A single injection well feeding two production wells producing fluid at moderate pressures is shown to be a potentially superior way to extract heat. Cyclic production is also demonstrated to have potential as a method for sweeping fluid through a larger volume of rock, thereby inhibiting flow channeling and increasing reservoir lifetime. 10 refs., 4 figs., 2 tabs.
Date:
January 1, 1991
Creator:
Robinson, B. A.
Object Type:
Article
System:
The UNT Digital Library
[Assessment of effects of surfactants in a heavy oil reservoir]. Third quarterly report, March 30, 1991
During the past three months we have carefully negotiated a joint venture to implement a pilot for testing the two enhanced oil recovery processes developed at CLD Technology, Inc. The technical staff at CLD Technology, Inc. has decided to model the heavy oil reserve on the Cantleberry Lease, the Jasmin oil field in Kern County, California. Staff members have designed a new sand pack to represent one-eighth (1/8) of a one, ten-acre, five-spot well pattern that will represent the sands of the Cantleberry lease. All calculated parameters are listed in Table 1. The 3-dimensional scaled physical model design represents a typical Cantleberry steamflood pattern. The design of the model will allow the creation of zones identical to those in the Cantleberry lease which will represent the shale break between the Cantleberry ``A`` and ``B`` sands. The last 3-dimensional scaled physical model experiment, needed to design the pilot, is ready to go awaiting continuous funding from the DOE.
Date:
April 8, 1991
Creator:
Kostura, J. A.
Object Type:
Report
System:
The UNT Digital Library
Surfactant-enhanced alkaline flooding field project
The Tucker sand of Helper (KS) field is a candidate for surfactant-enhanced alkaline flooding. The geology of the Helper site is typical of many DOE Class I reservoirs. The Tucker sand of Helper field was deposited in a fluvial dominated deltaic environment. Helper oil can be mobilized with either chemical system 2 or chemical system 3, as described in this report. Oil fields in the Gulf Coast region are also good candidates for surfactant-enhanced alkaline flooding. The results from laboratory tests conducted in Berea sandstone cores with oil brine from Helper (KS) field are encouraging. The crude oil is viscous and non-acidic and, yet, was mobilized by the chemical formulations described in this report. Significant amounts of the oil were mobilized under simulated reservoir conditions. The results in Berea sandstone cores were encouraging and should be verified by tests with field core. Consumption of alkali, measured with field core, was very low. Surfactant loss appeared to be acceptable. Despite the good potential for mobilization of Helper oil, certain reservoir characteristics such as low permeability, compartmentalization, and shallow depth place constraints on applications of any chemical system in the Tucker sand. These constraints are typical of many DOE Class I reservoirs. …
Date:
October 1, 1991
Creator:
French, T. R.
Object Type:
Report
System:
The UNT Digital Library
Technical support for geopressured-geothermal well activities in Louisiana
Continuous recording microearthquake monitoring networks have been established around US Department of Energy (DOE) geopressured-geothermal design wells in southwestern Louisiana and southeastern Texas since summer 1980 to assess the effects well development may have had on subsidence and growth-fault activation. This monitoring has shown several unusual characteristics of Gulf Coast seismic activity. The observed activity is classified into two dominant types, one with identifiable body phases (type 1) and the other with only surface-wave signatures (type 2). During this reporting period no type 1 or body-wave events were reported. A total of 230 type 2 or surface-wave events were recorded. Origins of the type 2 events are still not positively understood; however, little or no evidence is available to connect them with geopressured-geothermal well activity. We continue to suspect sonic booms from military aircraft or some other human-induced source. 37 refs., 16 figs., 6 tabs.
Date:
July 1, 1991
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library