The investigation and exploration of potential deep geothermal systems is based on detailed knowledge of their distinct reservoir characteristics. This is especially important in the exploration of potentially engineered geothermal systems and of mid to low enthalpy reservoir formations in greater depths, resp. In the early stages of geothermal reservoir exploration, characterization of the res...

H. C. Helgeson noted in 1968 that the salinity of the brine in the geothermal reservoir within the Salton Sea geothermal system generally increases from the top to the bottom and from the center to the sides. He also noted that pressure measurements at perforations in cased wells seemed to indicate that the formation fluids at the depths of production have a specific density about equal to 1, a...

A series of fossil spring deposits are exposed along the Dixie Valley fault just south of the producing geothermal field, in an area now characterized by active fumaroles and steaming ground. These deposits are composed of both travertine and sinter that have trapped pollen and other plant material during their formation. Radiocarbon dates on the organic material indicate that the youngest hot ...

Cuttings from geothermal wells in Dixie Valley, Nevada document the complex history of the Jurassic reservoir rocks now contained within the hanging wall of the Stillwater normal fault. Six stages of postOligocene alteration can be recognized on the basis of mineral paragenesis, rock associations, fluid-inclusion temperatures and apparent salinities. The paragenetic sequence from oldest to youn...

This paper presents a fundamental investigation of the use of conventional Rankine Cycle, Trilateral Flash Cycle, and wet vapour Rankine Cycle system for the generation of power from Enhanced Geothermal Systems. The paper considers ideal Carnot, Trilateral and Quadlateral cycles, and compares the ideal cases of maximum rate of power production with maximum total electricity delivery. These resu...

The past four years, geophysics students and faculty from Colorado School of Mines and Boise State University have studied the subsurface in the Upper Arkansas Valley, Colorado, using a combination of geological and geophysical methods. Here, we present and integrate their results from seismic, self-potential and gravity data, as well as water temperature measurements in local wells to ascertai...

In the perspective of increasing the share of renewable energies to mitigate global warming and to respond to fossil resources depletion, the use of geothermal resources for the polygeneration of energy services has gained interest and is expected to know an important development in the future. Some of the major issues linked with the use of geothermal energy concern the increase of the efficie...

Environmental Impact Assessment (EIA) has played an important role in environmental protection, especially in developing countries. It is an aid to decision-making and to the minimization or elimination of environmental impacts at an early planning stage. For geothermal energy, which currently plays an important part as a clean energy supply, a well-prepared Environmental Impact Assessment (EIA...

The accurate control of the wellbore pressure not only prevents lost circulation/blowout and fracturing formation by managing the density of the drilling fluid, but also improves productivity by mitigating reservoir damage. Calculating the geothermal pressure of a geothermal well by constant parameters would easily bring big errors, as the changes of physical, rheological and thermal properties...