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Altus Times (Altus, Okla.), Vol. 64, No. 18, Ed. 1 Tuesday, January 21, 1986 (open access)

Altus Times (Altus, Okla.), Vol. 64, No. 18, Ed. 1 Tuesday, January 21, 1986

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: January 21, 1986
Creator: Lobell, Joe
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 64, No. 69, Ed. 1 Tuesday, January 21, 1986 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 64, No. 69, Ed. 1 Tuesday, January 21, 1986

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: January 21, 1986
Creator: Brown, Leon
Object Type: Newspaper
System: The Portal to Texas History
Breakthrough Time for the Source-Sink Well Doublet (open access)

Breakthrough Time for the Source-Sink Well Doublet

A pressure transient analysis method is presented for interpreting breakthrough time between two constant rate wells. The wells are modeled as two line source wells in an infinite reservoir. The first well injects at a constant rate and the second well produces at a constant rate. We studied the effects of transient pressure conditions on breakthrough time. The first arrival of injected fluid at the production well may be significantly longer under transient condition than under steady state condition. A correlation of the deviation of the breakthrough time for transient pressure conditions from the steady state condition is presented.
Date: January 21, 1986
Creator: Menninger, Will & Sageev, Abraham
Object Type: Article
System: The UNT Digital Library
Chickasha Daily Express (Chickasha, Okla.), Vol. 95, No. 18, Ed. 1 Tuesday, January 21, 1986 (open access)

Chickasha Daily Express (Chickasha, Okla.), Vol. 95, No. 18, Ed. 1 Tuesday, January 21, 1986

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: January 21, 1986
Creator: Quinn, Jerry
Object Type: Newspaper
System: The Gateway to Oklahoma History
Conceptual Schematic Geologic Cross-Sections of the Geysers Steam Field (open access)

Conceptual Schematic Geologic Cross-Sections of the Geysers Steam Field

While formerly studied in terms of ancient Franciscan stratigraphy, The Geysers Steam Field now offers new views and interpretations on the deeper structure and importance of the lithocap, main metagraywacke, and felsic intrusive basement units with respect to the huge fractured reservoir. The Big Sulphur Creek enhanced tectonic disruption area provides the best situation for shallow felsite injection, shallow reservoir top, metasomatism transformation, and profound fracture permeability. Steam cells commonly extend to great depths and laterally drop off sharply, with relatively flat lateral continuance in some resource areas. Injectate ponding may offer a third fluid interface for reservoir steam reserves. A possible boiled down residuum of complex evaporates and hematite has been viewed in one area of the field where the reservoir (proper) bottom was encountered. Such a deposit may exist along all reservoir cell(s) bottoms, where in numerous cases the reservoir proper has been seen to pass into a somewhat mysterious ultra-superheated reservoir.
Date: January 21, 1986
Creator: Hebein, Jeffrey J.
Object Type: Article
System: The UNT Digital Library
Cooling of the Wairakei Reservoir During Production (open access)

Cooling of the Wairakei Reservoir During Production

After nearly 30 years of power generation, parts of the present production area at Wairakei are near the end of their economic life due to local cooling. To the west of the present production area there remains a large volume of high temperature resource whose deep liquid temperatures have not changed from those measured during the 1960's. Power generation can be maintained for many more years by producing from this high temperature resource.
Date: January 21, 1986
Creator: Bixley, Paul F.
Object Type: Article
System: The UNT Digital Library
The Coupling of the Numerical Heat Transfer Model of the Pauzhetka Hydrothermal System (Kamchatka, USSR) with Hydroisotopic Data (open access)

The Coupling of the Numerical Heat Transfer Model of the Pauzhetka Hydrothermal System (Kamchatka, USSR) with Hydroisotopic Data

The application of the two-dimensional numerical heat-transfer model to the Pauzhetka hydrothermal system allowed us to establish that: (1) a shallow magma body with the anomalous temperature of 700-1000 C and with a volume of 20-30 km{sup 3} may be a heat source for the formation of the Pauzhetka hydrothermal system. (2) The water feeding source of the Pauzhetka hydrothermal system may be meteoric waters which are infiltrated at an average rate of 5-10 kg/s {center_dot} km{sup 2}. The coupling of the numerical heat-transfer model with hydroisotopic data (D,T,{sup 18}O) obtained from the results of testing of exploitation wells, rivers and springs is the basis to understand more clearly the position of recharge areas and the structure of water flows in the hydrothermal system.
Date: January 21, 1986
Creator: Kiryukhin, A.V. & Sugrobov, V.M.
Object Type: Article
System: The UNT Digital Library
Customized Well Test Methods for a Non-Customary Geothermal Well (open access)

Customized Well Test Methods for a Non-Customary Geothermal Well

Recent testing of Thermal 4, The Geysers blowout well, has shown that the flow has two different components: a low enthalpy, mineral-laden flow from a well drilled within the existing wellhead and a high flowrate, high enthalpy annular flow. The commingled flows were mechanically separated and individually tested. The results of the test show that the flows are from two very different sources that are in weak hydraulic communication. Work is in progress to apply this information to bring Thermal 4 within compliance of the 1986 air quality regulations.
Date: January 21, 1986
Creator: Burr, Myron
Object Type: Article
System: The UNT Digital Library
Deliverability and its Effect on Geothermal Power Costs (open access)

Deliverability and its Effect on Geothermal Power Costs

The deliverability of liquid-dominated geothermal reservoirs is presented in terms of reservoir performance, and wellbore performance. Water influx modeling is used to match the performance of Wairakei in New Zealand, arid Ahuachapan in El Salvador. The inflow performance is given in terms of a linear productivity index for liquid-only flow, and a solution-gas drive relationship for two-phase flow. A 9-5/8'' production well is assumed, flowing 250 C water from 900 m depth, with a wellhead pressure of 100 psia. A Geothermal Development Model, that couples reservoir deliverability and power plant performance, and assigns costs to both, is used to illustrate how the development cost of geothermal electric power projects can be estimated.
Date: January 21, 1986
Creator: Gudmundsson, J. S. & Marcou, J. A.
Object Type: Article
System: The UNT Digital Library
Dual Permeability Modeling of Flow in a Fractured Geothermal Reservoir (open access)

Dual Permeability Modeling of Flow in a Fractured Geothermal Reservoir

A three dimensional fracture system synthesis and flow simulation has been developed to correlate drawdown characteristics measured in a geothermal well and to provide the basis for an analysis of tracer tests. A new dual permeability approach was developed which incorporates simulations at two levels to better represent a discrete fracture system within computer limitations. The first incorporates a discrete simulation of the largest fractures in the system plus distributed or representative element simulation of the smaller fractures. the second determines the representative element properties by discrete simulation of the smaller fractures. The fracture system was synthesized from acoustic televiewer data on the orientation and separation of three distinct fracture sets, together with additional data from the literature. Lognormal and exponential distributions of fracture spacing and radius were studied with the exponential distribution providing more reasonable results. Hydraulic apertures were estimated as a function of distance from the model boundary to a constant head boundary. Mean values of 6.7, 101 and 46 {micro}m were chosen as the most representative values for the three fracture sets. Recommendations are given for the additional fracture characterization needed to reduce the uncertainties in the model.
Date: January 21, 1986
Creator: Miller, John D. & Allman, David W.
Object Type: Article
System: The UNT Digital Library
Enhancement of Steam Phase Relative Permeability Due to Phase Transformation Effects in Porous Media (open access)

Enhancement of Steam Phase Relative Permeability Due to Phase Transformation Effects in Porous Media

An experimental study of two-phase concurrent flow of steam and water conducted (Verma et al., 1985) and a set of relative permeability curves was obtained. These curves were compared with semi-empirical results (Brooks and Corey, 1964) and experimental results obtained by other investigators (Johnson et al., 1959, and Osoba et al., 1951) for two-phase, two-component flow (oil/gas; gas/water; gas/oil). It was found that while the wetting phase relative permeabilities were in good agreement, the relative permeability for the steam phase was considerably higher than the relative permeabilities of the non-wetting phase (oil in oil/water and non-condensing gas in gas/oil or gas/water) in two-component systems (Figs. 1 and 2). This enhancement of steam relative permeability is attributed to phase transformation effects at the pore level in flow channels. There are two separate mechanisms by which phase transformation affected relative permeability CUTVBS (1) phase transformation in converging-diverging flow channels with hydrophilic walls can cause an enhancement of steam phase relative permeability; and (2) phase transformation along the interface of a stagnant phase and the phase flowing around it controls the irreducible phase saturation of the stagnant phase (Verma, 1986). A pore level model was considered to study the first mechanism. In this …
Date: January 21, 1986
Creator: Verma, A. & Pruess, K.
Object Type: Article
System: The UNT Digital Library
Evaluation of Porous Medium Permeability by Acoustic Logging Finds Geothermal Applications (open access)

Evaluation of Porous Medium Permeability by Acoustic Logging Finds Geothermal Applications

In a well, after an acoustic waveform has circulated through the surrounding porous media, the study of its alteration can help in evaluating their permeability. The treatment of the acoustic compressional wave's first three cycles yields a unique parameter called I-c. The recording of this I-c log all along any open hole interval is now possible by respecting some practical rules known by logging companies. Large flows of fluid found in geothermal low-enthalpy operations have provided an opportunity to check the validity of this method. Cumulative I-c derived permeability with depth (''EXAFLO'' log) correlates with the flowmeter log, as examples will show. Some new aspects of the theory underlying the I-c/permeability relationship have been developed and are described here.
Date: January 21, 1986
Creator: Conche, B.; Lebreton, F. & Rojas, J.
Object Type: Article
System: The UNT Digital Library
The Evolution and Natural State of Large-Scale Vapor-Dominated Zones (open access)

The Evolution and Natural State of Large-Scale Vapor-Dominated Zones

Numerical simulation is used to define the rather special conditions under which large-scale vapor-dominated zones can evolve. Given an adequate supply of heat, a vapor-dominated zone can evolve within low-permeability barriers without changes in rock properties or boundary conditions. However, the evolution of the system is accelerated in cases involving an initially high fluid throughflow rate that decreases with time. Near-steady-state pressures within the vapor-dominated zone are shown to vary with depth to the caprock.
Date: January 21, 1986
Creator: Ingebritsen, S.E.
Object Type: Article
System: The UNT Digital Library
A Field Study of Tracer and Geochemistry Behavior During Hydraulic Fracturing of a Hot Dry Rock Geothermal Reservoir (open access)

A Field Study of Tracer and Geochemistry Behavior During Hydraulic Fracturing of a Hot Dry Rock Geothermal Reservoir

Tracer and geochemistry measurements in fractured Hot Dry Rock (HDR) geothermal reservoirs are usually performed after a fracture connection has been established and constant, nearly equal inlet and outlet flow rates have been achieved. however, during hydraulic fracturing experiments designed to create a low-impedance fracture connection between two wells, the inlet and outlet flow rates can be dramatically different and can vary during the test, forcing us to revise the common analytical methods for interpreting tracer response curves and geochemistry behavior. This study presents tracer and geochemistry data from several hydraulic fracturing experiments at the Fenton Hill, NM, HDR geothermal reservoir. Tracers have been injected at various times during these tests: (1) initially, before any flow communication existing between the wells; (2) shortly after a flow connection was established; and (3) after the outlet flow had increased to its steady state value. An idealized flow model consisting of a combination of main fracture flow paths and fluid leakoff into secondary permeability explains the different tracer response curves for these cases, and allows us to predict the fracture volume of the main paths. The geochemistry during these experiments supports our previously developed models postulating the existence of a high concentration indigenous …
Date: January 21, 1986
Creator: Robinson, Bruce A.
Object Type: Article
System: The UNT Digital Library
Fracture Detection and Mapping (open access)

Fracture Detection and Mapping

Because the costs of drilling, completing, and testing a well can be extremely high, it is important to develop better tools and methods for locating high permeability zones prior to drilling, and to develop better tools and methods for identifying and characterizing major fracture zones during the drilling and well testing stages. At the recommendation of the LBL Industry Review Panel on Geothermal Reservoir Technology, we organized and convened a one-day workshop this past July to discuss various aspects of DOE's current and planned activities in fracture detection, to review the geothermal industry's near-term and long-term research needs, to determine the priority of those needs, to disseminate to industry the status of research in progress, and to discuss the possibility of future joint research between industry and DOE. In this paper we present a brief overview of the workshop from the perspective of those who participated in it and provided us with written comments to a questionnaire that was distributed.
Date: January 21, 1986
Creator: Goldstein, Norman E. & Iovenitti, Joseph L.
Object Type: Article
System: The UNT Digital Library
Fracture Detection: Interpretation of Well Logs to Select Packer Seats and Locate Injection Intervals (open access)

Fracture Detection: Interpretation of Well Logs to Select Packer Seats and Locate Injection Intervals

A wireline and mud logging program has been conducted in conjunction with redrilling operations in well EE-3 at the Fenton Hill Hot Dry Rock (HDR) site near Valles Caldera, New Mexico. The trajectory for the new bore, EE-3A, penetrated a fractured zone stimulated from adjacent well EE-2 and thereby established hydraulic communication. To test and stimulate selected zones in EE-3A inflatable open hole packers designed for high temperature service were used. Proper identification and selection of packer seats was crucial to the success of the project. The logging program successfully identified five competent packer seats in six attempts. Wireline temperature, caliper, sonic televiewer and natural gamma ray logs were used in conjunction with mud logs, drill cuttings and drilling parameter data to locate fractures, out-of-gage hole, temperature anomalies and mineralized zones which were avoided in selection of the packer seats.
Date: January 21, 1986
Creator: Dreesen, D. S.; Burns, K. L.; Chavez, P.; Dash, Z. V.; Kelkar, S.; Kolar, J. et al.
Object Type: Article
System: The UNT Digital Library
Geothermal Two-Phase Wellbore Flow: Pressure Drop Correlations and Flow Pattern Transitions (open access)

Geothermal Two-Phase Wellbore Flow: Pressure Drop Correlations and Flow Pattern Transitions

In this paper we present some basic concepts of two-phase flow and review the Orkiszewski (1967) correlations which have been suggested by various investigators to perform well for geothermal wellbore flow situations. We also present a flow regime map based on the transition criteria used by Orkiszewski (1967) and show that most geothermal wells flow under slug flow regime. We have rearranged bubble- to slug-flow transition criterion used by Orkiszewski (1967) to show that the transition depends on the dimensionless pipe diameter number in addition to dimensionless liquid and gas velocity numbers. Our aim is also to identify what research may lead to improvements in two-phase pressure drop calculations for geothermal wellbore flow.
Date: January 21, 1986
Creator: Ambastha, A. K. & Gudmundsson, J. S.
Object Type: Article
System: The UNT Digital Library
The Hereford Brand (Hereford, Tex.), Vol. 85, No. 140, Ed. 1 Tuesday, January 21, 1986 (open access)

The Hereford Brand (Hereford, Tex.), Vol. 85, No. 140, Ed. 1 Tuesday, January 21, 1986

Daily newspaper from Hereford, Texas that includes local, state, and national news along with advertising.
Date: January 21, 1986
Creator: Curtis, Jeri
Object Type: Newspaper
System: The Portal to Texas History

[Historic Property, Photograph 1981-05]

Photograph of a historic property in Texas.
Date: January 21, 1986
Creator: Texas Historical Commission
Object Type: Photograph
System: The Portal to Texas History
Hot Spring Monitoring at Lassen Volcanic National Park, California 1983-1985 (open access)

Hot Spring Monitoring at Lassen Volcanic National Park, California 1983-1985

Data collected on several occasions between 1983 and 1985 as part of a hydrologic monitoring program by the U.S. Geological Survey permit preliminary estimation of the natural variability in the discharge characteristics of hydrothermal features in Lassen Volcanic National Park and the Lassen KGRA in northern California. The total rate of discharge of high-chloride hot springs along Mill Creek and Canyon Creek in the Lassen KGRA has averaged 20.9 {+-} 1.7 L/s, based on seven measurements of the flux of chloride in these streams. Measured chloride flux does not appear to increase with streamflow during the spring-summer snowmelt period, as observed at Yellowstone and Long Valley Caldera. The corresponding fluxes of arsenic in Mill Creek and Canyon Creek decrease within distances of about 2 km downstream from the hot springs by approximately 30%, most likely due to chemical absorption on streambed sediments. Within Lassen Volcanic National Park, measurements of sulfate flux in streams draining steam-heated thermal features at Sulphur Works and Bumpass Hell have averaged 7.5 {+-} 1.0 and 4.0 {+-} 1.5 g/s, respectively. Calculated rates of steam upflow containing, dissolved H{sub 2}S to supply these sulfate fluxes are 1.8 kg/s at Sulphur Works and 1.0 kg/s at Bumpass Hell.
Date: January 21, 1986
Creator: Sorey, Michael L.
Object Type: Article
System: The UNT Digital Library
Inert and Reacting Tracers for Reservoir Sizing in Fractured, Hot Dry Rock Systems (open access)

Inert and Reacting Tracers for Reservoir Sizing in Fractured, Hot Dry Rock Systems

Flow characterization and volumetric sizing techniques using tracers in fractured hot dry rock reservoirs are discussed. Statistical methods for analyzing the residence time distribution (RTD) are presented. Tracer modal volumes and RTD shape are correlated with reservoir performance parameters such as active heat transfer area and dispersion levels. Chemically reactive tracers are proposed for mapping advance rates of cooled regions in HDR reservoirs, providing early warning of thermal drawdown. Important reaction rate parameters are identified for screening potential tracers. Current laboratory research and field work is reviewed.
Date: January 21, 1986
Creator: Tester, J. W.; Robinson, B. A. & Ferguson, J. H.
Object Type: Article
System: The UNT Digital Library
The Influence of Groundwater Flow on Thermal Regimes in Mountainous Terrain (open access)

The Influence of Groundwater Flow on Thermal Regimes in Mountainous Terrain

Active circulation of cool groundwater in mountainous terrain can cause an advective disturbance of the thermal regime. This factor complicates interpretation of data collected in geothermal exploration programs. An isothermal free-surface model has been developed which provides qualitative insight into the nature of an advective disturbance as it is affected by topography, permeability and climate. A fully coupled model of fluid and heat transfer is being developed for quantitative study of idealized mountain hydrothermal systems.
Date: January 21, 1986
Creator: Forster, Craig & Smith, Leslie
Object Type: Article
System: The UNT Digital Library
Initial Measurements of Petrophysical Properties on Rocks from the Los Azufres, Mexico, Geothermal Field (open access)

Initial Measurements of Petrophysical Properties on Rocks from the Los Azufres, Mexico, Geothermal Field

Petrophysical properties of geothermal reservoir rocks are valuable information for many activities, including reservoir characterization, modeling, field test analysis and planning of exploitation techniques. Petrophysical data of rocks from geothermal reservoirs located in volcanic areas is in general very scarce. In particular, no petrophysical data of rocks from the Los Azufres geothermal field area has ever been published. This work presents the results of initial petrophysical studies on outcrop rocks and drill core samples from the Los Azufres geothermal field. These studies are the first part of an ongoing experimental program intended to establish a data-base about physical properties of the Los Azufres rocks, in support of the many reservoir engineering activities which require of such information. The experimental work carried out consisted of laboratory measurements of density, porosity, permeability, compressibility, thermal conductivity, thermal expansion, electrical resistivity and sonic wave velocities. Some of the experiments were aimed at investigation of the effects of temperature, pressure, saturation and other parameters on the physical properties of rocks.
Date: January 21, 1986
Creator: Contreras, E.; Iglesias, E. & Razo, E.
Object Type: Article
System: The UNT Digital Library
Injectivity and Productivity Estimation in Multiple Feed Geothermal Wells (open access)

Injectivity and Productivity Estimation in Multiple Feed Geothermal Wells

A method is presented which allows individual zone injectivity/productivity to be determined without downhole flow measurements. Mass balance in conjunction with the specific pressure change measured at selected points in the well is related to the individual zone injectivity/productivity which can then be used to estimate productive capacity. A sample staged completion test program is presented to obtain the maximum information from a completed well without discharge or use of the downhole flow meter.
Date: January 21, 1986
Creator: Leaver, Jonathan D.
Object Type: Article
System: The UNT Digital Library