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Two-Mile Accelerator Project: Quarterly Status Report, 1 October to 30 December 1962

Description: Introduction: This is the third Quarterly Status Report of work under AEC Contract AT(04-3)-400, held by Stanford University. This contract provides for the construction of the Stanford Linear Accelerator Center (SLAC), a laboratory that will have as its chief instrument a two-mile-long linear electron accelerator.
Date: March 1963
Creator: Chu, E. L.; Ballam, J.; Neal, R. B.; Loew, G.; Eldredge, A. & DeStaebler, H.
Partner: UNT Libraries Government Documents Department

Two-Mile Accelerator Project: Quarterly Status Report, 1 January to 31 March 1963

Description: Introduction: This is the fourth Quarterly Status Report of work under AEC Contract AT(04-3)-400, held by Stanford University. This contract provides for the construction of the Stanford Linear Accelerator Center (SLAC), a laboratory that will have as its chief instrument a two-mile-long linear electron accelerator.
Date: May 1963
Partner: UNT Libraries Government Documents Department

Isotopic Discrimination of Some Solutes in Liquid Ammonia.

Description: The nitrogen isotopic discrimination of some salts and metals, studied in liquid ammonia solution at -50ºC, decreases in magnitude in the order Pb{sup++}, Ca{sup++}, Li{sup+}, Ag{sup+}, Na{sup+}, Li, K{sup+}, Na, K. The isotopic discrimination appears to provide qualitative information about the strength of the cation-solvent interaction in liquid amonia.
Date: January 1, 1966
Creator: Viste, A. & Taube, H.
Partner: UNT Libraries Government Documents Department

Geothermal Energy Development

Description: The Nation has embarked on an aggressive program to develop its indigenous resources of geothermal energy. For more than a decade, geothermal energy has been heralded as one of the more promising forms of energy alternate to oil and gas for electric power generation, but during the last fifteen years, the total capacity in the U.S. has reached 502 MWe, about half the size of a single modern nuclear power plant. And yet, the United States, especially its western and Gulf coast states, is believed to possess a vast resource base of geothermal heat at depths up to 3 to 10 km. Many estimates of these potential resources suitable for the production of electric power have been published and they range over a spectrum of more than a factor of 100. This variation suggests that the potential is essentially unknown. Table 1 gives a range of published forecasts for the year 1985 and the equivalent potential in number of 1000 Mwe power plants and in oil consumption in millions of barrels per day. In view of the estimated construction of about 200 to 250 nuclear power reactors by 1985-90, the pessimistic forecasts clearly show that the contribution of geothermal energy to the Nation's energy supply may indeed be small. The optimistic forecasts represent more than 15% of the total electric power requirements estimated for the year 1985. The Task Force for Geothermal Energy, in the Federal Energy Administration Project Independence Blueprint report of November 1974, established a national goal for 1985 of 20,000 to 30,000 MWe, the latter value representing an equivalent energy supply of one million barrels of oil per day. This goal was clearly a compromise between what is worth a national effort and what might be realistically achieved. The potential for adding or replacing the equivalent of ...
Date: November 3, 1975
Creator: Kruger, Paul
Partner: UNT Libraries Government Documents Department

Buoyancy Induced Boundary Layer Flows in Geothermal Reservoirs

Description: Most of the theoretical study on heat and mass transfer in geothermal reservoirs has been based on numerical method. Recently at the 1975 NSF Workshop on Geothermal Reservoir Engineering, Cheng presented a number of analytical solutions based on boundary layer approximations which are valid for porous media at high Rayleigh numbers. according to various estimates the Rayleigh number for the Wairakei geothermal field in New Zealand is in the range of 1000-5000, which is typical for a viable geothermal field consisting of a highly permeable formation and a heat source at sufficiently high temperature. The basic assumption of boundary layer theory is that heat convective heat transfer takes place in a thin porous layer adjacent to heated or cooled surfaces. Indeed, numerical solutions suggest that temperature and velocity boundary layers do exist in porous media at high Rayleigh numbers. It is worth mentioning that the large velocity gradient existing near the heated or cooled surfaces is not due to viscosity but is induced by the buoyancy effects. The present paper is a summary of the work that we have done on the analytical solutions of heat and mass transfer in a porous medium based on the boundary layer approximations since the 1975 Workshop. As in the classical convective heat transfer theory, boundary layer approximations in porous layer flows can result in analytical solutions. Mathematically, the approximations are the first-order terms of an asymptotic expansion which is valid for high Rayleigh numbers. Comparison with experimental data and numerical solutions show that the approximations are also accurate at moderate values of Rayleigh numbers. For problems with low Rayleigh numbers where boundary layer is thick, higher-order approximations must be used. 9 refs., 5 figs.
Date: December 1, 1976
Creator: Cheng, Ping
Partner: UNT Libraries Government Documents Department

Geothermal Reservoir Engineering Research

Description: This report first describes reservoir engineering within the broad field of petroleum engineering. The report next describes the general pattern of reservoir engineering in terms of performance observations, hypothesis construction and testing, and reservoir development planning, and emphasizes the importance of searching for the hypothesis about the nature of the reservoir system derived from all known facts instead of a model that includes only selected fact. The history since 1900 of gas, oil, and geothermal reservoir engineering research is briefly described.
Date: December 1, 1976
Creator: Ramey, H.J. Jr. & Miller, Frank G.
Partner: UNT Libraries Government Documents Department

Physical Model Studies of Explosion-Fractured Geothermal Reservoirs

Description: Large scale utilization of geothermal energy will require means for enhanced energy extraction from geothermal reservoirs since the higher quality hydrothermal resources adequate for commercial electricity generation represent only a small fraction of the estimated resource base. Technologies are being developed for artificial fracturing of hydrothermal and dry hot rock geothermal resources to obtain adequate permeability for water circulation and to expose new rock surface area. Non-isothermal processes such as in-place boiling or artificial circulation of cooler fluids can be used to extract the energy from the fractured formation. To evaluate non-isothermal heat transfer processes, physical model studies were conducted in the Stanford Geothermal Program fractured-rock reservoir model capable of operating at a maximum pressure of 800 psig at 500ºF. The 17-ft{sup 3} physical model has been described previously [Hunsbedt, Kruger, and London (1975), Hunsbedt (1975), and Hunsbedt, Kruger and London (1976)]. A summary of the characteristics of the relatively large fracture-permeability rock systems tested in the model are summarized in Table 1. The porosity and permeability characteristics of these systems resembled those of fracture-stimulated ones created by high-energy explosives. 1 tab., 4 refs., 2 figs.
Date: December 1, 1976
Creator: Hunsbedt, Anstein; Iregui, Roberto; Kruger, Paul & London, A. Louis
Partner: UNT Libraries Government Documents Department

Radon in Geothermal Reservoir Engineering

Description: Two general types of information related to transit time are amenable to radon measurement experiments. Under steady flow conditions, changes in the radon source will result in changes in the radon concentration in produced geofluids. And under steady emanation conditions, changes in the flow regime will also result in changes in the radon concentration. Current interest has focused on the relationship between radon concentration and the flow regime in producing geothermal reservoirs. The paper describes actual and planned experiments using radon as a tracer at The Geysers and other reservoirs. 1 tab., 4 refs., 2 figs.
Date: December 1, 1976
Creator: Kruger, Paul & Gary, Warren
Partner: UNT Libraries Government Documents Department

Heat Transfer in Nonisothermal Liquid Injection Experiments in Porous Media

Description: This paper discusses an analysis of the heat transfer phenomena in the bench-scale experiments being carried out in the Stanford Geothermal Program. The basis of this analysis was a series of simplified mathematical models of heat and mass transport in fine-grained porous media. The analysis determined that the thermal capacity of the coreholder system caused heat losses from the core which were not steady at early and medium times. This phenomenon had not been recognized previously. This was in spite of the fact that various authors previously had attempted to match the experimental behavior under discussion with their sophisticated computer models. These computer models did not account for the transient nature of the heat losses from the core. 8 refs., 3 figs.
Date: December 3, 1976
Creator: Atkinson, Paul G.
Partner: UNT Libraries Government Documents Department

Second workshop geothermal reservoir engineering: Proceedings

Description: The Arab oil embargo of 1973 focused national attention on energy problems. A national focus on development of energy sources alternative to consumption of hydrocarbons led to the initiation of research studies of reservoir engineering of geothermal systems, funded by the National Science Foundation. At that time it appeared that only two significant reservoir engineering studies of geothermal reservoirs had been completed. Many meetings concerning development of geothermal resources were held from 1973 through the date of the first Stanford Geothermal Reservoir Engineering workshop December 15-17, 1975. These meetings were similar in that many reports dealt with the objectives of planned research projects rather than with results. The first reservoir engineering workshop held under the Stanford Geothermal Program was singular in that for the first time most participants were reporting on progress inactive research programs rather than on work planned. This was true for both laboratory experimental studies and for field experiments in producing geothermal systems. The Proceedings of the December 1975 workshop (SGP-TR-12) is a remarkable document in that results of both field operations and laboratory studies were freely presented and exchanged by all participants. With this in mind the second reservoir engineering workshop was planned for December 1976. The objectives were again two-fold. First, the workshop was designed as a forum to bring together researchers active in various physical and mathematical branches of the developing field of geothermal reservoir engineering, to give participants a current and updated view of progress being made in the field. The second purpose was to prepare this Proceedings of Summaries documenting the state of the art as of December 1976. The proceedings will be distributed to all interested members of the geothermal community involved in the development and utilization of the geothermal resources in the world. Many notable occurrences took place between the ...
Date: December 3, 1976
Creator: Kruger, P. & Ramey, H.J. Jr. (eds.)
Partner: UNT Libraries Government Documents Department

Analysis of Geothermal Well Logs

Description: In the petroleum industry, well logging is a well developed discipline that has matured over a fifty-year period. Compared to this, geothermal well logging is a very new field of activity. The current practice is to use the same logging equipment and the same log interpretation techniques for geothermal wells as had been used for petroleum wells. However, this approach has proven either inadequate or ineffective in most geothermal areas. The problems here are of two types: (1) those associated with logging equipment and operation, and (2) those connected with log interpretation techniques. This paper focuses on the log interpretation aspects only. 6 refs.
Date: December 14, 1977
Creator: Sanyal, Subir K.
Partner: UNT Libraries Government Documents Department

Energy Extraction Experiments in the SGP Reservoir Model

Description: Experiments are being conducted in the Stanford Geothermal Program (SGP) large geothermal reservoir model utilizing rock systems with several characteristics resembling high permeability, fracture-stimulated systems. The broad objective of these experiments is to evaluate nonisothermal fluid production and heat transfer processes and to analytically model these for such rock systems. Three nonisothermal energy extraction and production processes, referred to here as in-place boiling, sweep, and steam-drive, were considered during the early phases of this study. The results showed that all three processes are feasible in the experimental systems considered. However, the effectiveness of the processes varied widely. The simple analytic models developed for the model reservoir and for the heat transfer from the rock successfully predicted the experimental results as long as the assumptions inherent in the models were not seriously violated. However, it was recognized that more detailed experimental and analytic studies of the heat transfer aspects were required, and such studies have since been performed by Iregui [Reference 4]. The final report of these results is in preparation and the highlights are given below. 2 tabs., 5 refs., 4 figs.
Date: December 14, 1977
Creator: Hunsbedt, A.; London, A.L.; Iregui, R.; Kruger, P. & Ramey, H.J. Jr.
Partner: UNT Libraries Government Documents Department

Third workshop on geothermal reservoir engineering: Proceedings

Description: The Third Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 14, 1977, with 104 attendees from six nations. In keeping with the recommendations expressed by the participants at the Second Workshop, the format of the Workshop was retained, with three days of technical sessions devoted to reservoir physics, well and reservoir testing, field development, and mathematical modeling of geothermal reservoirs. The program presented 33 technical papers, summaries of which are included in these Proceedings. Although the format of the Workshop has remained constant, it is clear from a perusal of the Table of Contents that considerable advances have occurred in all phases of geothermal reservoir engineering over the past three years. Greater understanding of reservoir physics and mathematical representations of vapor-dominated and liquid-dominated reservoirs are evident; new techniques for their analysis are being developed, and significant field data from a number of newer reservoirs are analyzed. The objectives of these workshops have been to bring together researchers active in the various physical and mathematical disciplines comprising the field of geothermal reservoir engineering, to give the participants a forum for review of progress and exchange of new ideas in this rapidly developing field, and to summarize the effective state of the art of geothermal reservoir engineering in a form readily useful to the many government and private agencies involved in the development of geothermal energy. To these objectives, the Third Workshop and these Proceedings have been successfully directed. Several important events in this field have occurred since the Second Workshop in December 1976. The first among these was the incorporation of the Energy Research and Development Administration (ERDA) into the newly formed Department of Energy (DOE) which continues as the leading Federal agency in geothermal reservoir engineering research. The Third Workshop under the Stanford Geothermal Program was supported ...
Date: December 15, 1977
Creator: Ramey, H.J. Jr. & Kruger, P. (eds.)
Partner: UNT Libraries Government Documents Department

Bench-scale experiments in the Stanford Geothermal Project

Description: The Stanford Geothermal Project bench-scale experiments are designed to improve the understanding of geothermal reservoir physics. Three sets of experiments are discussed in the following sections: (1) vapor pressure lowering in porous media due to capillarity and adsorption, (2) the effect of temperature on absolute permeability, and (3) the determination of steam-water relative permeability for drainage processes.
Date: January 1, 1978
Creator: Counsil, J.R.; Hsieh, C.H.; Ehlig-Economides, C.; Danesh, A. & Ramey, H.J., Jr.
Partner: UNT Libraries Government Documents Department

Compressional and shear wave velocities in water filled rocks during water-steam transition

Description: Both compressional and shear wave velocities were measured in water-filled Berea sandstone as a function of pore pressure under a constant confining pressure of 200 bar. At 145.5 C, compressional velocity increased from steam-saturated (low pore pressure) to water-saturated (high pore pressure) rock, whereas shear wave velocity decreased. Furthermore, a velocity minimum, attenuation and dispersions occur at water-steam transition for compressional wave. Results at 198 C show that both compressional and shear velocities decrease from steam-saturated to water-saturated rock, and a small velocity minimum is observed for compressional waves, but no attenuation nor dispersion occur. At both temperatures, the V{sub p}/V{sub s} ratio and Poisson's ratio increased from steam-saturated to water-saturated rock. The results are reasonably compatible with the mechanical effects of mixing steam and water fin the pore space near the phase transition, and may be applicable to in situ geothermal field evaluation.
Date: January 1, 1978
Creator: Hisao, Ito; DeVilbiss, John & Nur, Amos
Partner: UNT Libraries Government Documents Department

Introduction to the proceedings of the Fourth Geothermal Reservoir Engineering Workshop, Stanford Geothermal Program

Description: The program committee for the Fourth Geothermal Workshop, presented in mid-December, 1978, decided that the format of the last two geothermal workshops should be continued; that is, the objective should be documented talks on field phenomena and reports on important results of research directly applicable to geothermal energy development. An arranged panel discussion of problems of common importance was also built into the program. Finally, it was decided to publish all submitted papers in the proceedings, but to select papers for presentation at the workshop program.
Date: January 1, 1978
Creator: Kruger, Paul & Ramey, Henry J., Jr.
Partner: UNT Libraries Government Documents Department

Pressure drawdown analysis for the Travale 22 well

Description: This work presents preliminary results on the analysis of drawdown data for Travale 22. Both wellhead pressure and flow rate data were recorded in this well for over a period of almost two years. In the past, Barelli et al. (1975) and Atkinson et al. (1977) presented the analysis of five pressure buildup tests. Figure 1 shows the Horner plot for these cases. They found that to have a good match in all cases, it was necessary to assume that the Travale 22 well is intersected by a partially penetrating vertical fracture in a parallel-piped whose bottom side is maintained at constant pressure (boiling front), as shown in Fig. 2. Atkinson et al. also presented an analysis for a pressure interface test run in the Travale-Radicondoli area. In this case, the Travale 22 well was flowing and the pressure recorded at wells R1, R3, R5, R6, R9, and Chl (see Fig. 3 ) . Analysis of these data showed that pressure interference in this reservoir can be matched by considering pure linear flow (Figs. 4 and 5 ) . This indicated the possible presence of a vertical fracture intersecting the Travale 22 well. It was determined that fracture is oriented along the N73{sup o}W direction. In addition, the pressure interference data showed that no boundary exists within 2 kilometers from the fracture plane. It was mentioned that linear flow should take place in both horizontal and vertical directions.
Date: January 1, 1978
Creator: Barelli, A.; Brigham, W.E.; Cinco, H.; Economides, M.; Miller, F.G.; Ramey, H.J., Jr. et al.
Partner: UNT Libraries Government Documents Department

Recent developments in well test analysis in the Stanford Geothermal Program

Description: In the past year a number of studies pertaining to geothermal well test analysis were conducted. In this paper a brief overview of progress on the following six subjects is presented: (1) earth tide effects on a closed reservoir, (2) transient pressure analysis of multilayered heterogeneous reservoirs, (3) interference testing with wellbore storage and skin at the producing well, (4) steam/water relative permeabilities, (5) transient rate and pressure buildup resulting from constant pressure production, and (6) transient pressure analysis of a parallelepiped reservoir.
Date: January 1, 1978
Creator: Ehlig-Economides, C.
Partner: UNT Libraries Government Documents Department

Determination of TDS in Geothermal Systems by Well-Log Analysis

Description: An estimate of t h e chemistry of the fluid within a geothermal reservoir is required to establish the geological source and the possible environmental impact of the fluid as well as scaling and corrosion problems which might develop during production. While a detailed analysis of the chemical composition of a geothermal fluid can only be obtained from a water sample, an estimate of the total dissolved solids (TDS) in equivalent sodium chloride (NaCl) concentration can be obtained from well logs. TDS can also be useful in geological correlation between wells. TDS can be determined directly from a pulsed neutron log and a porosity log, (if the type of formation is known), or from the water resistivity, R{sub w}, and the temperature, T. Three approaches are used to find R{sub w}, and thus TDS. The first method uses a dual induction focused log and information from the log heading. Next, is found by employing an electrical log and a porosity log. The last approach utilizes the spontaneous potential log and header data. Examples are provided to illustrate the techniques described which utilize calculated values of R{sub w} to determine TDS.
Date: December 16, 1980
Creator: Brown, Susan L.; Gobran, Brian D. & Sanyal, Subir K.
Partner: UNT Libraries Government Documents Department

Effect of Temperature and Solution Composition on the Permeability of St. Peters Sandstone: Role of Iron (III)

Description: The purpose of this study was to systematically investigate effects of temperature and fluid composition on the permeability of quartz sandstones. We have concentrated our initial efforts on the time and flow dependence at 2 elevated temperatures (100°C, 200°C).
Date: December 16, 1980
Creator: Potter, J.M.; Nur, A. & Dibble, W.E. Jr.
Partner: UNT Libraries Government Documents Department

The Effect of Temperature on the Absolute Permeability to Distilled Water of Unconsolidated Sand Cores

Description: The work presented herein is a study of the effect of temperature on the absolute permeability to distilled water of unconsolidated sandstones at one confining pressure. The absolute permeability to distilled water of Ottawa silica sand was not dependent on the temperature level.
Date: December 16, 1980
Creator: Sageev, A.; Gobran, B.D.; Brigham, W.E. & Ramey, H.J. Jr.
Partner: UNT Libraries Government Documents Department