The geopressured-geothermal candidates for the Wells of Opportunity program were located by the screening of published information on oil industry activity and through direct contact with the oil and gas operators. This process resulted in the recommendation to the DOE of 33 candidate wells for the program. Seven of the 33 recommended wells were accepted for testing. Of these seven wells, six were actually tested. The first well, the No. 1 Kennedy, was acquired but not tested. The seventh well, the No. 1 Godchaux, was abandoned due to mechanical problems during re-entry. The well search activities, which culminated in the acceptance by the DOE of 7 recommended wells, were substantial. A total of 90,270 well reports were reviewed, leading to 1990 wells selected for thorough geological analysis. All of the reservoirs tested in this program have been restricted by one or more faults or permeability barriers. A comprehensive discussion of test results is presented.

The laboratory testing of the reactions of acetic, formic, hydrochloric, and hydrofluoric acids with calcium carbonate, kaolin, sepiolite, and two formation materials at geothermal temperatures is described. A workable test procedure was developed which provided information regarding the relative reactivities of selected minerals or formation materials with three of the four acids investigated. Tests with hydrochloric acid were complicated by reactions of the acid with the test vessel materials and therefore, only very limited work could be done with this acid at the desired temperatures. In spite of these difficulties, information regarding the amount of soluble material in the various acids was obtained. From this information an approximate value for the percent dissolution of the minerals under the different reaction conditions could be calculated. Additional information regarding the formation of solid secondary reaction products upon cooling of the reacted acid was also obtained. The implication of the mineral reactivities with the different acids and the formation of secondary solids on geothermal acidizing operations are discussed. Some selected scale inhibitors (for calcium carbonate) were tested for their hydrothermal stability. Their efficiency in inhibiting the formation of calcium carbonate scale before and after aging at 500/sup 0/F was measured. The implications of …

Three proposed DOE geopressured geothermal prospects defined by the Louisiana State University resource assessment group were screened for possible conflict with existing gas production. The analysis used the public records available at the Louisiana Department of Conservation offices in Baton Rouge and structural and statigraphic interpretations made by the L.S.U. resource assessment group. (MHR)

Field operations, which were conducted as a cooperative effort between Conoco and Gruy Federal, began on January 16, 1980 when the well was spudded. The well was drilled to 3692 feet, and 18 cores recovered in 18 core-barrel runs (144 feet). Upon completion of the coring phase, the hole was drilled to a total depth of 4150 feet and a complete suite of geophysical logs was run. Logging was then followed by completion and testing by Concoco. Core porosities agreed well with computed log porosities. Core water saturation and computed log porosities agree fairly well from 3692 to 3712 feet, poorly from 3712 to 3820 feet and in a general way from 4035 to 4107 feet. Computer log analysis techniques did not improve the agreement of log versus core derived water saturations. However, both core and log analysis indicated the ninth zone had the highest residual hydrocarbon saturations. Residual oil saturation were 259 STB/acre-ft for the 4035 - 4055 feet interval, and 150 STB/acre-ft for the 3692 - 3718 feet interval. Nine BOPD was produced from the 4035 - 4055 feet interval and no oil was produced from 3692 to 3718 feet interval, qualitatively confirming the relative oil saturations. The …

This report describes the laboratory testing of the reactions of acetic, formic, hydrochloric, ad hydrofluoric acids with calcium carbonate, kaolin, sepiolite, and two formation materials at geothermal temperatures. In general, a workable test procedure was developed which provided information regarding the relative reactivities of selected minerals or formation materials with three of the four acids investigated. Tests with hydrochloric acrid were complicated by reactions of the acid with the test vessel materials and therefore, only very limited work could be done with this acid at the desired temperatures. In spite of these difficulties, information regarding the amount of soluble material in the various acids was obtained. From this under the different reaction conditions could be calculated. Additional information regarding the formation of solid secondary reaction products upon cooling of the reacted acid was also obtained. The implication of the mineral reactivities with the different acids and the formation of secondary solids on geothermal acidizing operations are discussed. In addition, some selected scale inhibitors (for calcium carbonate) were tested for their hydrothermal stability. Their efficiency in inhibiting the formation of calcium carbonate scale before and after aging at 500{degree}F was measured. The implications of the loss of efficiency of these materials …

The geology north of Wells, Nevada is dominated by approximately 2150 m of Tertiary lacustrine siltstones and conglomerates. The sediments are cut by a high-angle, range-bounding fault and several associated step faults. Hydrothermal alteration and silicification are associated with the high-angle faults. Two ages of Quaternary sediments locally overlie the Tertiary sediments. Lithologic and well log analyses define numerous potential aquifers in the Tertiary sediments. The shallowest of these aquifers is overlain by a tuffaceous siltstone which appears to act as an aquitard for hot water moving through the aquifers. Three possible subsurface hydrologic models can be constructed to explain the spatial relationships of the thermal water near Wells. Cost-effective steps taken to expedite geothermal development in the area might include deepening of an existing domestic well in the city of Wells to at least 180 m in order to penetrate the tuffaceous siltstone aquitard, running borehole logs for all existing wells, and conducting a shallow temperature-probe survey in the Tertiary sediments north of Wells.

An areal distribution of heat and mass production in the Cerro Prieto field has been presented for two different times to determine the initial state of the ..cap alpha.. and ..beta.. aquifers and the behavior of the field under production. It was found that, initially, the ..cap alpha.. and ..beta.. aquifers were hot and very hot respectively. Cold boundaries to the field were found to be located toward the west and northeast. Initially, fluid production from most wells was very high. M-53 and some wells southeast of Fault H produced very hot fluids at very high rates. Production from most wells declined over the years, possibly due to scaling in the wellbore, reduced recharge to the aquifer, high resistance to flow due to silica precipitation in the reservoir pores and/or relative permeability effects in the two-phase regions surrounding the wells. In most wells fluid enthalpies declined over the years, perhaps due to mixing with colder waters either drawn in from upper strata and/or from the cold lateral boundaries depending upon well location.

Waters from the thermal springs of Washington range in chemical composition from dilute Na-HCO/sub 3/ to moderately saline CO/sub 2/-charged Na-HCO/sub 3/-Cl type waters. St. Martin's Hot Spring which discharges a slightly saline Na-Cl water, is the notable exception. The dilute Na-HCO/sub 3/ waters are generally associated with granitic intrusions; the warm to hot CO/sub 2/-charged waters issue on or near the large stratovolcanoes. The dilute waters have oxygen-isotopic compositions that indicate relatively little water-rock exchange. The CO/sub 2/-charged waters are usually more enriched in oxygen-18 due to more extensive water-rock reaction. The carbon-13 in the CO/sub 2/-charged thermal waters is more depleted (-10 to -12 %) than in the cold CO/sub 2/-charged soda springs (-2 to -8%) which are also scattered throughout the Cascades. The hot and cold CO/sub 2/-charged waters are supersaturated with respect to CaCO/sub 3/, but only the hot springs are actively depositing CaCO/sub 3/. Baker, Gamma, Sulphur, and Ohanapecosh hot springs seem to be associated with thermal aquifers of more than 100/sup 0/C. As these springs occur as individual springs or in small clusters, the respective aquifers are probably of restricted size.

This report describes disposal of liquids and, in some cases, suitable solids and/or entrapped gases, through: (1) well injection into deep permeable strata, bounded by impermeable layers; (2) grout injection into an impermeable host rock, forming fractures in which the waste solidifies; and (3) slurrying into excavated subsurface cavities. Radioactive materials are presently being disposed of worldwide using all three techniques. However, it would appear that if the techniques were verified as posing minimum hazards to the environment and suitable site-specific host rock were identified, these disposal techniques could be more widely used.

Mesaverde Group sandstone units in 13 closely-spaced wells in the central and southern Piceance Basin of Colorado were correlated utilizing wireline log response quantitatively and qualitatively. Based on these correlations, the environmental subdivisions of the Mesaverde Group were characterized as follows: (1) paralic (upper mixed-marine) zone, occurring in the uppermost Mesaverde Group, includes thick sandstone units which are interpreted to be regionally continuous, (2) fluvial zone, containing point-bars 20 to 30+ ft thick, is interpreted to be correlatable to a maximum of 6800 ft, and (3) paludal zone has insufficient data to adequately characterize the sand units. However, 63 percent of the units are correlatable across at least 139 ft. An approximation of the dimensional characteristics of Mesaverde sandstone units has potential applications in designing hydraulic fracturing treatments and estimating gas reserves more accurately. 15 figures, 2 tables.

The primary objective of the Bodcau In Situ Combustion Project was to demonstrate the operations and economics of a commercial scale in situ combustion project utilizing simultaneous air and water injection. This report includes pre-contract work, field facilities, injection and production performance, remedial work, monitoring, research support, a performance evaluation, and economics covering the contract life. The project was conducted on five patterns of Cities Service Company's Bodcau Fee B Lease. The five patterns were part of an eight-pattern expansion of Cities' combustion operations in the field. Thirty-eight producers, five injectors, and five observation wells were included in the patterns. Injection for the combustion phase (August 1976 through April 1981) was 10.1 BCF of air and 2.64 MM BBL of water. Cumulative water injection over project life was 5.15MM barrels. The combustion phase resulted in recovery of 626 M barrels of 19/sup 0/ API crude. Cumulative oil production amounted to 685 M barrels or 35% of the oil in place. Total expenditures for the project through June 30, 1982, were $10,450,790. Development costs for wells and equipment were $1,710,779.36; production and research services have amounted to $1,075,311; and lease operations and maintenance were $4,382,228. Decontrol tax amounted to $1,300,784. Total …

Analytical and numerical solutions are presented for the transient, radial temperature distribution in a porous medium which is subjected to a constant-rate injection of an incompressible fluid from a wellbore. The formulation includes energy transfer by conduction and convection, and the Danckwerts boundary condition is applied at the finite-radius wellbore. At late times, the numerical solutions approach a self-similar form which can be described in terms of the incomplete Gamma function. In typical petroleum and geothermal applications, convergence to the asymptotic similarity solutions occurs on a time scale of roughly one hour. The results are generally applicable to a broad range of convection-diffusion phenomena which are best described in radial coordinates.

Data from detailed analyses of production from geopressured geothermal aquifers suggest that appropriate brine production tests may well result in production of otherwise undiscoverable hydrocarbons. This paper reviews concepts for the biogenic origin of natural gas, subsurface migration of natural gas, and trapping of that gas in commercially producible reservoirs. Data are presented to demonstrate discovery of free natural gas by brine production from two dry wildcat wells. Finally, conditions under which brine production testing may be a prudent investment are discussed. 5 figures.

Multielement geochemical analysis of drill cuttings from three geothermal wells, Utah State 42-7, Utah State 31-33 and Forminco No. 1, in the Cove Fort-Sulphurdale KGRA, Utah, demonstrates that the distributions of different elements are the result of different chemical processes operating throughout the geologic history of the area. Statistical analysis of geochemical-data distributions confirm the presence of several distinct element associations. Of the 36 elements determined on the samples, 12 (V, Mo, Cd, Ag, Au, Sb, Bi, U, Te, Sn, B and Th) were present in concentrations at or below detection levels. Of the remaining 24 elements, only 3 (Ni, Co and Zr) are lognormally distributed. Distributions for the remaining elements are of aggregate populations which represent background, mineralization or other processes.

Two geothermal test wells were drilled in January 1983, in Antelope Canyon to access the potential for resource utilization by the City of Caliente's proposed space heating district. Both holes, drilled into bedrock at 220 feet, encountered hot water in the upper part of the hole (40 to 100 feet) and cooler water below (100 to 210 feet). A series of pumping tests were completed in February 1983, including pump-efficiency tests, stepped draw-down tests, and 1-, 2-, and 3-day sustained pumping tests. The test results indicated that the transmissivity of the thermal aquifer is very, very high. Five water samples were collected for chemical analyses during the course of CD-1 pump tests. The samples were collected to determine the water quality for the proposed space heating district and possible reinjection, and to establish a water chemistry base-line for comparative analysis of fluid chemistry during the course of the pumping and from subsequent development. 7 refs., 18 figs., 3 tabs.

This report investigates the feasibility of a geothermal heating system at the Ojo Caliente Mineral Springs Co. The geothermal energy will be used to preheat hot water for the laundry facilities and to heat the water for a two-pipe fan coil heating system in the hotel. Present annual heating fuel costs of $11,218 for propane will be replaced by electricity to operate fans and pump at an annual cost of $2547, resulting in a net savings of $8671. Installation costs include $10,100 for a well system, $1400 for a laundry system, and $41,100 for a heating system. With the addition of a 10% design fee the total installation cost is $57,860. Ignoring escalating propane fuel prices, tax credits for energy conservation equipment, and potential funding from the State of New Mexico for a geothermal demonstration project, the simple economic payback period for this project is 6.7 years.

Shell, in conjunction with the United States of America Department of Energy, is conducting a gravity stable displacement field test of the miscible CO/sub 2/ process. The test is being conducted in the portion of a fault sealed reservoir lying below a subsea depth of -12,750 feet. Injection of the CO/sub 2/ slug at the producing gas-oil contact commenced in October 1978. Injection of the 860 MM cubic foot slug was completed in February of 1980. The slug of CO/sub 2/ was moved downward through the watered out sand by production of downdip water. The leading edge of the displacement has reached the producing perforations and production of the oil column commenced on January 26, 1981. Conventional cores and the log-inject-log technique were used to determine residual oil saturation in a well drilled as the pilot producer. Pulsed neutron logging devices have been used to detect the CO/sub 2/ slug and monitor its subsequent movements in the vicinity of the production well. The monitor logs indicate the thickness of the oil column had increased during the displacement to the production perforations located 130 feet below the level of CO/sub 2/ injection. The 23 foot oil column remaining at initiation of …

Twenty-three shale samples ranging in depth from 5194 ft to 13,246 ft from Gulf Oil Corporation No. 2 Texas State Lease 53034 well and 33 shale samples ranging in depth from 2185 ft to 15,592 ft from General Crude Oil Company/Department of Energy No. 1 Pleasant Bayou well were examined by x-ray techniques to determine the mineralogy of the geopressured zone in the Brazoria Fairway. Both wells have similar weight-percent trends with depth for a portion of the mineralogy. Calcite decreases, and plagioclase, quartz and total clay increase slightly. Within the clays, illite in mixed-layer illite/smectite (I/S) increases and smectite in mixed-layer I/S decreases. Four minerals have distinctly different trends with depth for each well. In the No. 2 Texas State Lease 53034 well, potassium feldspar and mixed-layer I/S decrease, kaolinite increases, and discrete illite is constant. In the No. 1 Pleasant Bayou well, potassium feldspar and kaolinite are constant, mixed-layer I/S increases, and discrete illite decreases.

The potential for near-surface mineral resources in the Mount Hood Wilderness is low. Geochemical data suggest two areas of weak epithermal mineralization in the Zigzag Mountain part of the wilderness: (1) the Lost Creek-Burnt Lake-Cast Creek-Short Creek area on the north side of Zigzag Mountain where vein-type lead-zinc-silver mineralization occurs; and (2) the Lady Creek-Laurel Hill area on the south side of Zigzag Mountain where the upper part of a quartz diorite pluton has associated propylitic alteration resulting in some porphyry-type copper, gold, silver, lead, and zinc mineralization. Geothermal-resource potential for low- to intermediate-temperature (less than 248/sup 0/F, 120/sup 0/C) hot-water systems in the wilderness is moderate to high. Part of the wilderness is classified as a Known Geothermal Resources Area (KGRA) and two parts have been included in geothermal lease areas. Rock and gravel sources are present within the wilderness; however, quantities of similar and more accessible deposits are available outside the wilderness. Deposits outside the wilderness are large enough to supply local demand in the foreseeable future.

The results of geological, geochemical, and geophysical surveys in Wild Cattle Mountain and Heart Lake Roadless Areas indicate no potential for metallic or non-metallic mineral resources in the areas and no potential for coal or petroleum energy resources. However, Wild Cattle Mountain Roadless Area and part of Heart Lake Roadless Area lie in Lassen Known Geothermal Resources Area, and much of the rest of Heart Lake Roadless Area is subject to non-competitive geothermal lease applications. Both areas are adjacent to Lassen Volcanic National Park, which contains extensive areas of fumaroles, hot springs, and hydrothermally altered rock; voluminous silicic volcanism occurred here during late Pleistocene and Holocene time. Geochemical data and geological interpretation indicate that the thermal manifestations in the Park and at Morgan and Growler Hot Springs (immediately west of Wild Cattle Mountain Roadless Area) are part of the same large geothermal system. Consequently, substantial geothermal resources are likely to be discovered in Wild Cattle Mountain Roadless Area and cannot be ruled out for Heart Lake Roadless Area.

Equity Management Corporation proposes (1) to build about 30 condominiums at the present site of the Yucca Lodge, Truth or Consequences, New Mexico and (2) to heat the condominiums with the natural thermal waters that discharge from the property. To do so the corporation must satisfy the rules and regulations of four state and federal agencies. To satisfy some of the data requirements of these agencies and to provide basic data on the geohydrology of the area this report provides the results of a field inventory of the springs and wells within one mile of the lodge. Table 1 summarizes the data for eight springs and three sites where springs once issued. Table 2 summarizes the data on forty-four operable wells and thirty wells that are unusable in their present condition. Appendices list (1) wells presumed to be in the area but not located during field inspection and (2) wells that could be in the area, but were found to be beyond the one-mile radius. Temperature and specific conductance of the water show only minor variation within the recognized hot-water.

A groundwater monitoring program has been established on the Raft River Geothermal Site since 1978. The objective of this program is to document possible impacts that may be caused by geothermal production and injection on the shallow aquifers used for culinary and irrigation purposes. This annual progress report summarizes data from 12 monitor wells during 1981. These data are compared with long-term trends and are correlated with seasonal patterns, irrigation water use and geothermal production and testing. These results provide a basis for predicting long-term impacts of sustained geothermal production and testing. To date, there has been no effect on the water quality of the shallow aquifers.

The drilling of geothermal wells can result in near wellbore damage of both the injection wells and production wells if proper precautions are not taken. Very little specific information on the chemical causes for drilling damage that can directly be applied to the drilling of a geothermal well in a given situation is available in the literature. As part of the present work, the sparse literature references related to the chemical aspects of drilling damage are reviewed. The various sources of chemically induced drilling damages that are related to drilling operations are summarized. Various means of minimizing these chemical damages during and after the drilling of a geothermal well are suggested also.

For the purpose of characterizing the properties of the Eastern Devonian gas shale, a seven-day tracer experiment was carried out in August of 1981 by the Los Alamos National Laboratory as part of the DOE's Offset-Well Test. Two wells had been drilled in a Columbia Gas Company field in southeastern Ohio, each with a downhole separation of approximately 120 feet from an existing production well. The isoceles triangle formed by the three wells had an apex angle of approximately 110 degrees. About 56,000 SCF of nitrogen were injected into a producing zone located at a depth of 3300 feet in one of the wells. Gas was then produced from the various wells at different rates and pressures for the duration of the test. Both pressure and gas composition in the three wells were monitored throughout the test.