Search

Search Results

• 1. [Image] Steady-State and Transient Wellbore Temperatures during Drilling

  	An extensive literature search was made to locate technical publications and computer programs relating to wellbore temperatures during drilling operations. The search confirmed the need for knowledge ...
  	Citation × Citation Citation Abstract Copy Title: Steady-State and Transient Wellbore Temperatures during Drilling Author: McDonald, W.J. Year: 1976 An extensive literature search was made to locate technical publications and computer programs relating to wellbore temperatures during drilling operations. The search confirmed the need for knowledge of transient and steady state circulating temperatures in the design of geothermal bits. Two approaches were used in calculating borehole temperatures. The steady state solution of Holmes and Swift was programmed and 2100 cases calculated for various borehole configurations. For transient temperature studies, calculations were made for ten borehole configurations. These calculations help emphasize the need for better high temperature bit performance and improved engineering procedures in drilling. The conclusions and recommendations are based on latest available technology for calculating wellbore temperatures Title: Steady-State and Transient Wellbore Temperatures during Drilling Author: McDonald, W.J. Year: 1976 An extensive literature search was made to locate technical publications and computer programs relating to wellbore temperatures during drilling operations. The search confirmed the need for knowledge of transient and steady state circulating temperatures in the design of geothermal bits. Two approaches were used in calculating borehole temperatures. The steady state solution of Holmes and Swift was programmed and 2100 cases calculated for various borehole configurations. For transient temperature studies, calculations were made for ten borehole configurations. These calculations help emphasize the need for better high temperature bit performance and improved engineering procedures in drilling. The conclusions and recommendations are based on latest available technology for calculating wellbore temperatures Close

• 2. [Image] C. D. Hopkins, et al. , No. 2. Geothermal Well-Of-Opportunity, Wayne County, Georgia. Operational Report

  	An oil and gas exploration well, located near Jesup in Wayne County, Georgia (lat. 31/sup 0/32' N, long. 81/sup 0/43' W), was deepened and used for geothermal temperature-gradient measurements. The well ...
  	Citation × Citation Citation Abstract Copy Title: C. D. Hopkins, et al. , No. 2. Geothermal Well-Of-Opportunity, Wayne County, Georgia. Operational Report Author: Lohse, A. Year: 1978 An oil and gas exploration well, located near Jesup in Wayne County, Georgia (lat. 31/sup 0/32' N, long. 81/sup 0/43' W), was deepened and used for geothermal temperature-gradient measurements. The well was drilled from 4,009 to 4,341 feet, then diamond cored to 4,371 feet, 28 feet of core being obtained for analysis. After logging by the U.S.G.S. District Groundwater Office in Atlanta, the well was terminated with 3/sup 1///sub 2/'' tubing to 4,386 feet. The bottom-hole temperature was determined to be 60/sup 0/C (140/sup 0/F) at 1,331 meters (4,365 feet). Over the interval 47 to 1,331 meters (154 to 4,365 feet) the least-squares temperature gradient was 29.3 +- 0.14 /sup 0/C/km (1.61 +- 0.25 /sup 0/F/100 ft) Title: C. D. Hopkins, et al. , No. 2. Geothermal Well-Of-Opportunity, Wayne County, Georgia. Operational Report Author: Lohse, A. Year: 1978 An oil and gas exploration well, located near Jesup in Wayne County, Georgia (lat. 31/sup 0/32' N, long. 81/sup 0/43' W), was deepened and used for geothermal temperature-gradient measurements. The well was drilled from 4,009 to 4,341 feet, then diamond cored to 4,371 feet, 28 feet of core being obtained for analysis. After logging by the U.S.G.S. District Groundwater Office in Atlanta, the well was terminated with 3/sup 1///sub 2/'' tubing to 4,386 feet. The bottom-hole temperature was determined to be 60/sup 0/C (140/sup 0/F) at 1,331 meters (4,365 feet). Over the interval 47 to 1,331 meters (154 to 4,365 feet) the least-squares temperature gradient was 29.3 +- 0.14 /sup 0/C/km (1.61 +- 0.25 /sup 0/F/100 ft) Close

• 3. [Image] Annual Report on the Project to Design and Experimentally Test an Improved Geothermal Drill Bit

  	Progress is reported in a research and development program to design, build, and test an improved geothermal drill bit. The major tasks of the Phase I effort are entitled: failure mechanisms of existing ...
  	Citation × Citation Citation Abstract Copy Title: Annual Report on the Project to Design and Experimentally Test an Improved Geothermal Drill Bit Author: Barker, L.M. Year: 1976 Progress is reported in a research and development program to design, build, and test an improved geothermal drill bit. The major tasks of the Phase I effort are entitled: failure mechanisms of existing bits; new steels and new bearing design; and new seals and lubricants. It appears that a significant gain in drill-bit life can be attained by the use of higher-temperature steels which retain more hardness at temperatures above 260/sup 0/C (500/sup 0/F). Such steels are available, and two research bits of high-temperature steels were made and will shortly be tested in a laboratory-simulated full-scale geothermal drilling environment. Two control bits of the same design, but made with conventional drill bit steels, were also obtained for identical laboratory test runs, so that the performance of the research bits can be meaningfully assessed. Base-line properties of the steels, such as hardness and fracture toughness as functions of temperature, are being measured to further assess the value of the high-temperature steels selected for the research bits. A geothermal test vessel was designed and fabricated in which the full-scale drill bits will be tested. The vessel is capable of temperature to 427/sup 0/C (800/sup 0/F) and pressures to 35 MPa (5,000 psi). Seal and lubrication designs were studied, and the state of the art in high-temperature seals and lubricants was assessed. Some candidate seals and lubricants have been obtained for testing, and others are being procured. In addition, a seal test vessel has been designed and will soon be completed which can simulate the geothermal drilling environment in full-scale testing of seal and lubricant designs and materials. (JGB) Title: Annual Report on the Project to Design and Experimentally Test an Improved Geothermal Drill Bit Author: Barker, L.M. Year: 1976 Progress is reported in a research and development program to design, build, and test an improved geothermal drill bit. The major tasks of the Phase I effort are entitled: failure mechanisms of existing bits; new steels and new bearing design; and new seals and lubricants. It appears that a significant gain in drill-bit life can be attained by the use of higher-temperature steels which retain more hardness at temperatures above 260/sup 0/C (500/sup 0/F). Such steels are available, and two research bits of high-temperature steels were made and will shortly be tested in a laboratory-simulated full-scale geothermal drilling environment. Two control bits of the same design, but made with conventional drill bit steels, were also obtained for identical laboratory test runs, so that the performance of the research bits can be meaningfully assessed. Base-line properties of the steels, such as hardness and fracture toughness as functions of temperature, are being measured to further assess the value of the high-temperature steels selected for the research bits. A geothermal test vessel was designed and fabricated in which the full-scale drill bits will be tested. The vessel is capable of temperature to 427/sup 0/C (800/sup 0/F) and pressures to 35 MPa (5,000 psi). Seal and lubrication designs were studied, and the state of the art in high-temperature seals and lubricants was assessed. Some candidate seals and lubricants have been obtained for testing, and others are being procured. In addition, a seal test vessel has been designed and will soon be completed which can simulate the geothermal drilling environment in full-scale testing of seal and lubricant designs and materials. (JGB) Close

• 4. [Image] California Laws for Conservation of Geothermal Resources

  	California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells
  	Citation × Citation Citation Abstract Copy Title: California Laws for Conservation of Geothermal Resources Author: State of California Year: 1978 California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells Title: California Laws for Conservation of Geothermal Resources Author: State of California Year: 1978 California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells Close

• 5. [Image] California Laws for Conservation of Geothermal Resources, January 1989

  	California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells
  	Citation × Citation Citation Abstract Copy Title: California Laws for Conservation of Geothermal Resources, January 1989 Author: State of California Year: 1989 California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells Title: California Laws for Conservation of Geothermal Resources, January 1989 Author: State of California Year: 1989 California laws for the conservation of geothermal resources. This covers rules for drilling geothermal wells Close

• 6. [Image] Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California

  	The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and ...
  	Citation × Citation Citation Abstract Copy Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustic logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of Drilling were most Useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustic logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of Drilling were most Useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Close

• 7. [Image] Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California

  	The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California, from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and ...
  	Citation × Citation Citation Abstract Copy Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California, from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustics logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of drilling were most useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Title: Geological and Geophysical Analysis of Coso Geothermal Exploration Hole No. 1 (CGEH-1), Coso Hot Springs KGRA, California Author: Galbraith, R.M. Year: 1978 The Coso Geothermal Exploration Hole number one (CGEH-1) was drilled in the Coso Hot Springs KGRA, California, from September 2 to December 2, 1977. Chip samples were collected at ten foot intervals and extensive geophysical logging surveys were conducted to document the geologic character of the geothermal system as penetrated by CGEH-1. The major rock units encountered include a mafic metamorphic sequence and a leucogranite which intruded the metamorphic rocks. Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the drillhole itself was strongly influenced by structural zones. Water chemistry indicates that this geothermal resource is a hot-water rather than a vapor-dominated system. Several geophysical logs were employed to characterize the drillhole geology. The natural gamma and neutron porosity logs indicate gross rock type and the acoustics logs indicate fractured rock and potentially permeable zones. A series of temperature logs run as a function of time during and after the completion of drilling were most useful in delineating the zones of maximum heat flux. Convective heat flow and temperatures greater than 350/sup 0/F appear to occur only along an open fracture system encountered between depths of 1850 and 2775 feet. Temperature logs indicate a negative thermal gradient below 3000 feet Close

• 8. [Image] Proceedings of the Geothermal Power Development Conference, University of California, Berkeley, June 18, 1974

  	The Atomic Energy Commission (AEC) is interested in receiving comments, recommendations and suggestions concerning arrangements appropriate to conduct during FY 1975 and into the early 1980's of research ...
  	Citation × Citation Citation Abstract Copy Title: Proceedings of the Geothermal Power Development Conference, University of California, Berkeley, June 18, 1974 Author: Lawrence Berkeley Laboratory Year: 1974 The Atomic Energy Commission (AEC) is interested in receiving comments, recommendations and suggestions concerning arrangements appropriate to conduct during FY 1975 and into the early 1980's of research and development work and pilot projects aimed at establishing the technical, economic and practical feasibility of electric and non-electric power production from geothermal resources, including possible cooperative programs between the AEC and other organizations. Responses received will be utilized in the further development of AEC's long-range geothermal program plan. The geothermal program objective is to stimulate and facilitate early and significant commercial utilization of these resources. This program is a part of the national geothermal energy research and development effort and is designed to contribute toward meeting overall national energy needs Title: Proceedings of the Geothermal Power Development Conference, University of California, Berkeley, June 18, 1974 Author: Lawrence Berkeley Laboratory Year: 1974 The Atomic Energy Commission (AEC) is interested in receiving comments, recommendations and suggestions concerning arrangements appropriate to conduct during FY 1975 and into the early 1980's of research and development work and pilot projects aimed at establishing the technical, economic and practical feasibility of electric and non-electric power production from geothermal resources, including possible cooperative programs between the AEC and other organizations. Responses received will be utilized in the further development of AEC's long-range geothermal program plan. The geothermal program objective is to stimulate and facilitate early and significant commercial utilization of these resources. This program is a part of the national geothermal energy research and development effort and is designed to contribute toward meeting overall national energy needs Close

• 9. [Image] Geothermal Energy Resource Assessment

  	This report covers the objectives and the status of a long-range program to develop techniques for assessing the resource potential of liquid-dominated geothermal systems. Field studies underway in northern ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal Energy Resource Assessment Author: Wollenberg, H.A. Year: 1975 This report covers the objectives and the status of a long-range program to develop techniques for assessing the resource potential of liquid-dominated geothermal systems. Field studies underway in northern Nevada comprise a systematic integrated program of geologic, geophysical, and geochemical measurements, necessary to specify a drilling program encompassing heat flow holes, deep calibration holes, and ultimately, deep test wells. The status of Nevada field activities is described. The areas under study are in a region characterized by high heat flow where temperatures at depth in some geothermal systems exceed 180 C. Areas presently being examined include Beowawe Hot Springs in Whirlwind Valley. Buffalo Valley Hot Springs, Leach Hot Springs in Grass Valley, and Kyle Hot Springs in Buena Vista Valley. Geologic studies encompass detailed examinations of structure and lithology to establish the geologic framework of the areas. The geothermal occurrences are characterized by zones of intense fault intersection, which furnish permeable channelways for the introduction of meteoric water into regions of high temperature at depth Title: Geothermal Energy Resource Assessment Author: Wollenberg, H.A. Year: 1975 This report covers the objectives and the status of a long-range program to develop techniques for assessing the resource potential of liquid-dominated geothermal systems. Field studies underway in northern Nevada comprise a systematic integrated program of geologic, geophysical, and geochemical measurements, necessary to specify a drilling program encompassing heat flow holes, deep calibration holes, and ultimately, deep test wells. The status of Nevada field activities is described. The areas under study are in a region characterized by high heat flow where temperatures at depth in some geothermal systems exceed 180 C. Areas presently being examined include Beowawe Hot Springs in Whirlwind Valley. Buffalo Valley Hot Springs, Leach Hot Springs in Grass Valley, and Kyle Hot Springs in Buena Vista Valley. Geologic studies encompass detailed examinations of structure and lithology to establish the geologic framework of the areas. The geothermal occurrences are characterized by zones of intense fault intersection, which furnish permeable channelways for the introduction of meteoric water into regions of high temperature at depth Close

• 10. [Image] Thermal Gradient and Heat Flow Drilling, Volume 5, Final Report

  	During the summer of 1975, the Department of Geology and Geophysics drilled nine drill thermal gradient/heat flow holes. Total footage drilled was 2125 feet. Seven holes were drilled with a Mayhew 1000 ...
  	Citation × Citation Citation Abstract Copy Title: Thermal Gradient and Heat Flow Drilling, Volume 5, Final Report Author: Whelan, J.A. Year: 1977 During the summer of 1975, the Department of Geology and Geophysics drilled nine drill thermal gradient/heat flow holes. Total footage drilled was 2125 feet. Seven holes were drilled with a Mayhew 1000 drill using various combinations of down the hole hammer drilling, rotary drilling, and NX diamond core drilling. Three of these were heat flow holes--one in the Mineral Range, one in the Tushar Range near Beaver, Utah, and one near Monroe, Utah. Two were alteration study holes in the Roosevelt KGRA and two were temperature gradient holes, in alluvium in the Roosevelt KGRA. The average depth of the holes drilled with the Mayhew 1000 drill was 247 feet. Holes ranged from 135 feet to 492 feet. Cost per foot averaged $18.53. Two holes were core drilled with a Joy 12, BX-size drill. One was to 75 feet, in perlite. This hole was abandoned. The other was to 323 feet in granite. These holes averaged $13.82 per foot. Permission to drill was obtained from BLM and drill sites were inspected with BLM personnel to avoid disturbing archeological sites. Sites were reseeded where disturbed. Holes were completed by setting capped one-inch black iron pipe, backfilling the hole with cuttings to 10 feet from surface and cementing to the surface Title: Thermal Gradient and Heat Flow Drilling, Volume 5, Final Report Author: Whelan, J.A. Year: 1977 During the summer of 1975, the Department of Geology and Geophysics drilled nine drill thermal gradient/heat flow holes. Total footage drilled was 2125 feet. Seven holes were drilled with a Mayhew 1000 drill using various combinations of down the hole hammer drilling, rotary drilling, and NX diamond core drilling. Three of these were heat flow holes--one in the Mineral Range, one in the Tushar Range near Beaver, Utah, and one near Monroe, Utah. Two were alteration study holes in the Roosevelt KGRA and two were temperature gradient holes, in alluvium in the Roosevelt KGRA. The average depth of the holes drilled with the Mayhew 1000 drill was 247 feet. Holes ranged from 135 feet to 492 feet. Cost per foot averaged $18.53. Two holes were core drilled with a Joy 12, BX-size drill. One was to 75 feet, in perlite. This hole was abandoned. The other was to 323 feet in granite. These holes averaged $13.82 per foot. Permission to drill was obtained from BLM and drill sites were inspected with BLM personnel to avoid disturbing archeological sites. Sites were reseeded where disturbed. Holes were completed by setting capped one-inch black iron pipe, backfilling the hole with cuttings to 10 feet from surface and cementing to the surface Close