Download or read book Analysis of Production Data from the Krafla Geothermal Field Iceland written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Krafla geothermal field in northeastern Iceland consists of several zones, which contain fluids of different composition and thermodynamic state (Stefansson, 1981). In this paper they examine production data from wells which are completed in two-phase zones. Transient changes in flow rate and flowing enthalpy are analyzed to obtain insight into relative (liquid and gas phase) permeabilities, and other reservoir parameters. Numerous studies have shown that predictions of geothermal reservoir behavior are strongly dependent upon the choice of relative permeability functions. There is an extensive literature on gas-oil and oil-water relative permeabilities, but steam-water relative permeabilities which are needed for geothermal reservoir analysis are poorly known. Laboratory experiments by Chen et al. (1978) and Counsil and Ramey (1979) have provided some data which, however, seem to be at variance with relative permeability characteristics deduced from field data by Grant (1977) and Horne and Ramey (1978). The differences may reflect uncertainties in the analysis methods used, or they may reflect ''real'' differences in relative permeability behavior of fractured reservoirs from that of porous medium-type laboratory cores. Recent theoretical work by Menzies (1982) and Gudmundsson et al. (1983) has substantiated the relative permeability characteristics obtained by Horne and Ramey (1978) for Wairakei wells.
Download or read book Analysis of Production Data from the Krafla Geothermal Field Iceland written by K. Pruess and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Summary of Modeling Studies of the Krafla Geothermal Field Iceland written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive modeling study of the Krafla geothermalfield in Iceland has been carried out. The study consists of four tasks:the analysis of well test data, modeling of the natural state of summaryof the the field, the determination of the generating capability of thefield, and modeling of well performance. The results of all four tasksare consistent with field observation.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1984 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geophysical Imaging Methods for Analysis of the Krafla Geothermal Field NE Iceland written by Beatrice Smith Parker and published by . This book was released on 2012 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Joint geophysical imaging techniques have the potential to be reliable methods for characterizing geothermal sites and reservoirs while reducing drilling and production risks. In this study, we applied a finite difference tomography method and a double-difference tomography method to image the P- and S-wave velocity structure of the Krafla geothermal reservoir in Northeastern Iceland. We combined over 450 new microearthquakes from a network of borehole seismometers from September 2008 and June-July 2011 with over 800 events recorded by surface networks between 2004 and 2008 that were obtained from the Iceland Geosurvey. Starting event locations were determined from the Joint Hypocenter Determination method. Absolute and relative arrival times were used for the two tomographic inversions to jointly invert for event hypocenter locations and velocity structure. Finally, we compared the final velocity structures with a resistivity model determined from a magnetotelluric inversion. Overall, the earthquakes were located in a tight cluster just south of the IDDP well, concentrated into a horizontal layer centered at 2km depth, and oriented in a NW-SE direction by both tomography methods. The main cluster of earthquake locations is at a saddle point of the resistivity model and near regions of low resistivity. Both methods yielded similar overall velocity models, with a locally low velocity region near the surface and a locally high velocity region moving deeper into the model. We have interpreted a high density intrusion, a gas-filled fracture zone, and a possible partial melt region based on the P-wave, S-wave, and Vp/Vs ratio anomalies in the velocity model. Synthetic modeling of the relationship between the resistivity and velocity models demonstrated the complexities of integrating two data sets with signals of different wavelength and resolution. However, with a better understanding of this relationship and knowledge of physical parameters such as porosity, a better constrained joint-inversion of magentotelluric and seismic data will be possible in the future.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1984 with total page 1278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SVARTSENGI FIELD PRODUCTION DATA AND DEPLETION ANALYSIS written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There have been two major high-temperature geothermal field developments in Iceland in the last decade; Krafla in the north-east, and Svartsengi in the south-west. These and other geothermal developments have recently been reported by Palmason et al. The Krafla field will not be discussed here, but details about the field are available in Stefansson and the power plant in Eliasson et al. Several reservoir engineering studies of the Krafla field have been published. The Svartsengi field is one of several fields on the Reykjanes Peninsula in south-west Iceland. About 15 km west of Svartsengi, on the tip of the Peninsula, the Reykjanes field is now under development, primarily for seawater chemicals production. The recently drilled Eldvorp field is located in line between these two fields, about 5 km west of Svartsengi. There are also several fields to the east of Svartsengi, at 15-20 km distance. The Svartsengi, Eldvorp, and Reykjanes fields exist in the same tectonic-volcanic environment, and are surrounded by similar geohydrological conditions, as discussed by Georgsson; see also Gudmundsson et al. and Franzson. Optimum development of these and other fields on the Reykjanes Peninsula, requires an understanding of their depletion behavior with time; that is, how the reservoir pressure falls with production. While recognizing that no two geothermal fields are alike, we also realize that an understanding of the depletion behavior of Svartsengi, for example, may prove useful in the development of other similar and nearby fields. The main purpose of this paper is to report our depletion analysis of the Svartsengi field using lumped-parameter and water influx modeling: we also report the field's production history.
Download or read book Reservoir Engineering Study of the Krafla Hvitholargeothermal Area Iceland written by UNU Geothermal Training Programme (Iceland). and published by . This book was released on 1985 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Summary of Modeling Studies of the Krafla Geothermal Field Iceland written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of the Krafla Geothermal Field written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Simulation studies have recently been made of the Krafla Geothermal Field in Northern Iceland. The field is close to boiling in the formation at depths of 1800 meters and below. Two simulations were undertaken. The first studied radial flow, i.e., behavior around a production well. It was found that the relative permeability distribution of the liquid and vapor phase had very little effect on the general results. The simulation shows that while the well produced superheated steam after a few days of production, the superheated front moved only 1/10 the distance of the boiling front, which extended to a radial distance of over 200 meters after one-half year production. The second simulation investigated the two-zone system which is believed to exist in Krafla. This study simulated one well producing 50 kg/s from both zones for a period of 33 years. It showed that boiling in the formation begins near the production well and at the connection between the two zones. After 20 years, boiling takes place in the entire lower zone region with saturation (steam volume fraction) ranging from 0-30 percent. After 33 years, saturation increased to over 60 percent at the top of the lower zone, just under the caprock separating the two zones. Higher production rates will augment the spread of the saturation proportionately to the ratio of mass production.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1985 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.
Download or read book PRESSURE BUILDUP MONITORING OF THE KRAFLA GEOTHERMAL FIELD ICELAND written by and published by . This book was released on 1985 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A break in electrical power generation from the Krafla geothermal plant was planned from beginning of May to early September 1984. Early in June most of the production wells were shutin and their pressure recovery monitored. A regular monitoring of the pressure buildup was carried out on a well to well basis until mid-August, when the wells were put back into production except for wells 12 and 16. They were used to monitor the pressure drawdown due to the start of production. This was abruptly brought to an end by a nearby volcanic eruption in early September. The pressure buildup in the two-phase geothermal reservoir at Krafla is described and the first results presented. The results are compared with parameters determined on the completion of the wells and with predictions from numerical simulations of the reservoir. Finally the status of the Krafla geothermal system is discussed with regard to the comparison.
Download or read book Engineering and Economic Assessment of Geothermal Resources written by and published by . This book was released on 1987 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation of the Krafla Geothermal Field written by V. Jonsson and published by . This book was released on 1978 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1985 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1984 with total page 1332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geophysics Tectonics Abstracts written by and published by . This book was released on 1987 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
