A Fracture Modeling System has been developed by Electric Power Development Company (EPDC) to facilitate the interpretation, display and analysis of fractures identified by borehole imaging tools. Borehole images of individual fractures provide understanding of the local properties of the fracture itself. If an integrated model of the field’s large-scale fracture system could be developed, it w...

The Earth Sciences Division of Lawrence Berkeley Laboratory in cooperation with the Instituto Costarricense. de Electricidad is conducting a reservoir engineering study of the Miravalles geothermal field, Costa Rica. Using data from eight exploration wells, a two-dimensional areal, natural-state model of Miravalles has been developed. The model was calibrated by fitting the observed temperature...

A set of key issues pertaining to the environmental performance of geothermal electric power have been addressed. They include: 1) greenhouse gas emissions (GHG) from geothermal facilities, 2) the use of supercritical carbon dioxide (scCO2) as a geofluid for enhanced geothermal systems (EGS), 3) quantifying the impact of well field exploration on the life cycle of geothermal power, and finally ...

At the Kakkonb geothermal area, Japan, a large Quaternary granitic body is dstributed below ca 2.5 km ckpth from the surface, associating with thick high-temperature contact me&amorphic zones in the overlying formations, and a meteoric-water-cbminated type hydrothermal system is developedat present time. During the 'Deep-seated Geothermal Resources Survey', WD-la well was drilled to 3729 m dept...

magnetotellurics (mt) is a geophysical passive technique for exploring geothermal reservoirs. it utilizes a broad spectrum of natural geomagnetic fields for electromagnetic induction in the earth. this method is also preferred over dc-resistivity methods, particularly where the exploration of subsurface deep aquifers is considered. the role of mt method in the exploration of geothermal reservoi...

Information about the times of thermal breakthrough and subsequent rates of thermal drawdown in enhanced geothermal systems (EGS) is necessary for reservoir management, designing fracture stimulation and well drilling programs, and forecasting economic return. Thermal breakthrough in heterogeneous porous media can be estimated using conservative tracers and assumptions about heat transfer rates...

The Queensland Government recently awarded A$15 million to the University of Queensland to establish a new “hot rocks” research and development centre, called the Queensland Geothermal Energy Centre of Excellence. The vision for the Centre is to provide urgent, forward looking research, development and support for establishment of geothermal energy as a clean energy option through a program of ...

Continuous monitoring of in situ reservoir responses to stress transients provides insights into the evolution of geothermal reservoirs. By exploiting the stress dependence of seismic velocity changes, we investigate the temporal evolution of the reservoir stress state of the Salton Sea geothermal field (SSGF), California. We find that the SSGF experienced a number of sudden velocity reductions...

Geoscientists from the Coso Operating Company, EGI-Utah, GeoMechanics International, and the U.S. Geological Survey are cooperating in a multi-year study to develop an Enhanced Geothermal System (EGS) in the Coso Geothermal Field. Key to the creation of an EGS is an understanding of the relationship among natural fracture distribution, fluid flow, and the ambient tectonic stresses that exist wi...