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Integrated High Resolution Microearthquake Analysis and Monitoring for Optimizing Steam Production at The Geysers Geothermal Field, California

Description: In December of 2003 a large amount of water from the Santa Rosa wastewater project began being pumped to The Geysers for injection. Millions of dollars are being spent on this injection project in the anticipation that the additional fluid will not only extend the life of The Geysers but also greatly increase the net amount of energy extracted. Optimal use of the injected water, however, will require that the water be injected at the right place, in the right amount and at the proper rate. It h… more
Date: April 26, 2004
Creator: Majer, Ernest; Peterson, John; Stark, Mitch; Smith, Bill; Rutqvist, Jonny & Kennedy, Mack
Partner: UNT Libraries Government Documents Department
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A Comprehensive Study of Fracture Patterns and Densities in The Geysers Geothermal Reservoir Using Microearthquake Shear-Wave Splitting Tomography

Description: In this project we developed a method for using seismic S-wave data to map the patterns and densities of sub-surface fractures in the NW Geysers Geothermal Field/ (1) This project adds to both the general methods needed to characterize the geothermal production fractures that supply steam for power generation and to the specific knowledge of these in the Geysers area. (2)By locating zones of high fracture density it will be possible to reduce the cost of geothermal power development with the ta… more
Date: February 24, 2004
Creator: Malin, Peter E.; Shalev, Eylon; Lou, Min; Simiyu, Silas M.; Stroujkova, Anastasia & McCausland, Windy
Partner: UNT Libraries Government Documents Department
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Characterization of Fracture Patterns in the Geysers Geothermal Reservoir by Shear-wave Splitting

Description: The authors have analyzed the splitting of shear waves from microearthquakes recorded by a 16-station three-component seismic network at the Northwest Geysers geothermal field, Geysers, California, to determine the preferred orientation of subsurface fractures and cracks. Average polarization crack directions with standard deviation were computed for each station. Also, graphical fracture characterizations in the form of equal-area projections and rose diagrams were created to depict the result… more
Date: September 15, 1999
Creator: Erten, D. & Rial, J. A.
Partner: UNT Libraries Government Documents Department
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Thermal History of the Felsite Unit, Geysers Geothermal Field, From Thermal Modeling of 40Ar/39Ar Incremental Heating Data

Description: An Ar-40/Ar-39 and U-Pb study was performed of the Geysers plutonic complex of the Geysers Geothermal Field in California. Sixty-nine ion microprobe spot analyses of zircons from four granite samples from the plutonic complex that underlies the Geysers geothermal field yielded Pb-207/Pb-206 vs. U-238/Pb-206 concordia ages ranging from 1.13 {+-} 0.04 Ma to 1.25 {+-} 0.04 Ma. The U-Pb ages coincide closely with Ar-40/Ar-39 age spectrum plateau and ''terminal'' ages from coexisting K-feldspars and… more
Date: August 19, 1999
Creator: California), T. M. Harrison (U of; U), G. B. Dalrymple (Oregon State; Utah), J. B. Hulen (U of; Lanphere, M. A.; Grove, M. & Lovera, O. M.
Partner: UNT Libraries Government Documents Department
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A comprehensive study of fracture patterns and densities in the Geysers geothermal reservoir using microearthquake shear-wave splitting tomography. Quarterly report for Sep-Dec 1998

Description: We start organizing the computer programs needed for crack density inversion into an easy to follow scripts. These programs were collection of bits and pieces from many sources and we want to organize those separate programs into coherent product. We also gave a presentation (enclosed) in the Twenty-Fourth Workshop on Geothermal Reservoir Engineering in Stanford University on our Geyser and Mammoth results.
Date: March 31, 1999
Creator: Malin, Peter E. & Shalev, Eylon
Partner: UNT Libraries Government Documents Department
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A comprehensive study of fracture patterns and densities in the Geysers geothermal reservoir using microearthquake shear-wave splitting tomography [Quarterly progress report 06/16/1998 - 09/15/1998]

Description: We completed the process of locating events and identifying shear-wave splitting in the mammoth area. A total of 2250 split shear wave observations were recorded in the four month period that our network was in place. Fast polarization direction map in Figure 1 shows that most of the stations in the mammoth area display consistent direction throughout the main field, between 300{degree} azimuth to 0{degree} azimuth. Some exemptions to the consistent crack alignment (fast polarization direction)… more
Date: March 26, 1999
Creator: Malin, P.E. & Shalev, E.
Partner: UNT Libraries Government Documents Department
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A comprehensive study of fracture patterns and densities in the Geysers geothermal reservoir using microearthquake shear-wave splitting tomography. [Quarterly progress report 03/16/1998 - 06/15/1998]

Description: We completed the process of identifying shear-wave splitting in the Geyser area. A total of 2700 observations were recorded with about 1700 observations from the 1988 data and about 1000 observations from 1994. Fast polarization direction map in Figure 1 shows that most of the stations in the Geyser area display consistent direction throughout the main field, between 0{degree} azimuth to 40{degree} azimuth. Some exemptions to the consistent crack alignment (fast polarization direction) can be s… more
Date: March 17, 1999
Creator: Malin, P.E. & Shalev, E.
Partner: UNT Libraries Government Documents Department
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Literature Survey on Cements for Remediation of Deformed Casing in Geothermal Wells

Description: Brookhaven National Laboratory was requested to conduct a literature survey for the best available cement to use in the proposed casing patch as part of the Geothermal Drilling Organization (GDO) project on remediation of deformed casings. A total of 50 wells have been identified with deformed production casing in Unocal`s portion of The Geysers geothermal field. A procedure to address the casing deformation and avoid abandonment of these wells has been developed as described in the Geysers Def… more
Date: December 31, 1998
Creator: Allan, M. L. & Philippacopoulos, A. J.
Partner: UNT Libraries Government Documents Department
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Vertical arrays for fracture mapping in geothermal systems

Description: In collaboration with UNOCAL Geothermal Operations, Los Alamos National Laboratory assessed the feasibility of using vertical arrays of borehole seismic sensors for mapping of microseismicity in The Geysers geothermal field. Seismicity which arises from minute displacements along fracture or fault surfaces has been shown in studies of seismically active oil reservoirs to be useful in identifying fractures affected by and possibly contributing to production. Use of retrievable borehole seismic p… more
Date: December 1, 1998
Creator: Albright, J. N.; Rutledge, J. T.; Fairbanks, T. D.; Thomson, J. C. & Stevenson, M. A.
Partner: UNT Libraries Government Documents Department
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LITERATURE SURVEY ON CEMENTS FOR REMEDIATION OF DEFORMED CASING IN GEOTHERMAL WELLS

Description: Brookhaven National Laboratory was requested to conduct a literature survey for the best available cement to use in the proposed casing patch as part of the Geothermal Drilling Organization (GDO) project on remediation of deformed casings. A total of 50 wells has been identified with deformed production casing in Unocal's portion of The Geysers geothermal field. Reduced internal diameter and casing doglegs result in lost production and the possible need for abandonment. The cause of the deforma… more
Date: November 1, 1998
Creator: Allan, M. L. & Philippacopoulos, A. J.
Partner: UNT Libraries Government Documents Department
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Geothermal regimes of the Clearlake region, northern California

Description: The first commercial production of power from geothermal energy, at The Geysers steamfield in northern California in June 1960, was a triumph for the geothermal exploration industry. Before and since, there has been a search for further sources of commercial geothermal power in The Geysers--Clear Lake geothermal area surrounding The Geysers. As with all exploration programs, these were driven by models. The models in this case were of geothermal regimes, that is, the geometric distribution of t… more
Date: June 1, 1998
Creator: Amador, M.; Burns, K. L. & Potter, R. M.
Partner: UNT Libraries Government Documents Department
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Water adsorption at high temperature on core samples from The Geysers geothermal field

Description: The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal field, California, was measured at 150, 200, and 250 C as a function of steam pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption and desorption runs were made in order to investigate the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were made on the same rock samples. Mercury intrusion p… more
Date: June 1, 1998
Creator: Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M. & Mesmer, R.E.
Partner: UNT Libraries Government Documents Department
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Water adsorption at high temperature on core samples from The Geysers geothermal field

Description: The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal reservoir, California, was measured at 150, 200, and 250 C as a function of pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and the extent of the hysteresis. Additionally, low temperature gas adsorption analyse… more
Date: June 1, 1998
Creator: Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M. & Mesmer, R.E.
Partner: UNT Libraries Government Documents Department
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Stanford geothermal program. Final report, July 1990--June 1996

Description: This report discusses the following: (1) improving models of vapor-dominated geothermal fields: the effects of adsorption; (2) adsorption characteristics of rocks from vapor-dominated geothermal reservoir at the Geysers, CA; (3) optimizing reinjection strategy at Palinpinon, Philippines based on chloride data; (4) optimization of water injection into vapor-dominated geothermal reservoirs; and (5) steam-water relative permeability.
Date: March 1, 1998
Partner: UNT Libraries Government Documents Department
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Southeast geysers effluent pipeline project. Final report

Description: The project concept originated in 1990 with the convergence of two problems: (1) a need for augmented injection to mitigate declining reservoir productivity at the Geysers; and (2) a need for a new method of wastewater disposal for Lake County communities near the The Geysers. A public/private partnership of Geysers operators and the Lake County Sanitation District (LACOSAN) was formed in 1991 to conduct a series of engineering, environmental, and financing studies of transporting treated waste… more
Date: January 15, 1998
Creator: Dellinger, M.
Partner: UNT Libraries Government Documents Department
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Final cost reduction study for the Geysers Recharge Alternative. Volume 1

Description: The purpose of this study is to determine whether or not cost reduction opportunities exist for the Geysers Recharge Alternative as defined in the Santa Rosa Subregional Long-Term Wastewater Project EIR/EIS. The City of Santa Rosa has been directed to have a plan for reclaimed water disposal in place by 1999 which will meet future capacity needs under all weather conditions. A Draft EIR/EIS released in July 1996 and a Final EIR certified in June 1997 examine four primary alternatives plus the N… more
Date: November 1, 1997
Partner: UNT Libraries Government Documents Department
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Induced seismicity. Final report

Description: The objective of this project has been to develop a fundamental understanding of seismicity associated with energy production. Earthquakes are known to be associated with oil, gas, and geothermal energy production. The intent is to develop physical models that predict when seismicity is likely to occur, and to determine to what extent these earthquakes can be used to infer conditions within energy reservoirs. Early work focused on earthquakes induced by oil and gas extraction. Just completed re… more
Date: September 18, 1997
Creator: Segall, P.
Partner: UNT Libraries Government Documents Department
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Decline curve analysis of vapor-dominated reservoirs

Description: Geothermal Program activities at the INEEL include a review of the transient and pseudosteady state behavior of production wells in vapor-dominated systems with a focus on The Geysers field. The complicated history of development, infill drilling, injection, and declining turbine inlet pressures makes this field an ideal study area to test new techniques. The production response of a well can be divided into two distinct periods: transient flow followed by pseudo-steady state (depletion). The t… more
Date: May 1, 1997
Creator: Faulder, D. D.
Partner: UNT Libraries Government Documents Department
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Volatility of HCl and the thermodynamics of brines during brine dryout

Description: Laboratory measurements of liquid-vapor partitioning (volatility) of chlorides from brines to steam can be used to indicate the potential for corrosion problems in geothermal systems. Measurements of volatilities of solutes in chloride brines have established a possible mechanism for the production of high-chloride steam from slightly acidic high temperature brines. Questions concerning the fate of NaCl in the steam production process have been addressed through extensive measurements of its vo… more
Date: April 1, 1997
Creator: Simonson, J. M. & Palmer, D. A.
Partner: UNT Libraries Government Documents Department
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Relating x-ray attenuation measurements to water content and distribution in SB-15D core

Description: Making improved estimates of the water content of The Geysers reservoir is fundamental to efficient and economic long term production of steam power from the resource. A series of coordinated physical properties measurements form core recovered from the SB-15D, reported in this volume in a series of papers, have been made to better understand water storage and to relate water content and distribution to observable geophysical properties such as electrical conductivity and seismic velocities. A … more
Date: September 30, 1996
Creator: Bonner, B. P.; Roberts, J. J. & Schneberk, D. J
Partner: UNT Libraries Government Documents Department
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Heat flow and hot dry rock geothermal resources of the Clearlake Region, northern California

Description: The Geysers-Clear Lake geothermal anomaly is an area of high heat flow in northern California. The anomaly is caused by abnormally high heat flows generated by asthenospheric uplift and basaltic magmatic underplating at a slabless window created by passage of the Mendocino Triple Junction. The Clear Lake volcanic field is underlain by magmatic igneous bodies in the form of a stack of sill-form intrusions with silicic bodies generally at the top and basic magmas at the bottom. The tabular shape … more
Date: August 1, 1996
Creator: Burns, K.L.
Partner: UNT Libraries Government Documents Department
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Permeability-thickness determination from transient production response at the southeast geysers

Description: The Fetkovich production decline curve analysis method was extended for application to vapor-dominated geothermal reservoirs for the purpose of estimating the permeability-thickness product (kh) from the transient production response. The analytic dimensionless terms for pressure, production rate, decline rate, and decline time were derived for saturated steam using the real gas potential and customary geothermal production units of pounds-mass per hour. The derived terms were numerically valid… more
Date: August 1, 1996
Creator: Faulder, D. D.
Partner: UNT Libraries Government Documents Department
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Reservoir technology research at the INEL

Description: Reservoir engineering research at INEL was aimed at developing a better understanding of The Geysers and developing better tools with which to study flow in fractured geothermal reservoirs in general. Two specific topics were studies in the last year: matrix fracture interactions and decline curve analysis. A third project, revisiting the behavior of the `high-temperature reservoir` (HTR), was started near the end of 1995. These projects are being conducted in collaboration with other researche… more
Date: May 1, 1996
Creator: Renner, J. L.; Shook, G. M. & Faulder, D. D.
Partner: UNT Libraries Government Documents Department
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