.n a number of geothermal systems, including the 3eysers (Ca), Lardarello (Italy) and Tongonan :Philippines), well logs indicate that in some parts of he reservoir, a two-phase vapouror liquid-dominated -egion is overlain by a colder liquid saturated zone. The stability of such systems is intriguing. Schubert md Straus (1980) have described how a liquid layer nay overly a model superheated vapo...

High temperature geothermal systems are the modern analogue of epithermal precious metal ore deposits. In these systems, gold and silver are transported primarily as bisulfide complexes, with the precious metals being deposited in response to boiling and mixing of the deep geothermal fluid. In order for the geothermal system to produce an economic precious metal deposit within the typical lifet...

Liquid-dominated hydrothermal reservoirs, which contain saline fluids at high temperatures and pressures, have a significant potential for contamination of the environment by heavy metals. The design of the power conversion cycle in a liquid-dominated geothermal plant is a key factor in determining the impact of the installation. Reinjection of the fluid into the reservoir minimizes heavy metal...

Enhanced Geothermal Systems (EGS) are engineered reservoirs created to economically extract heat from low permeability and/or porosity geothermal resources. Existing geochemical reactive transport models for such systems lack essential data on the structure of the pore systems in geothermal reservoirs, and how they evolve in the relevant ranges of temperature, pressure, composition, and length ...

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...

The tectonic position of Egypt in the northeastern corner of the African continent suggests that it may possess significant geothermal resources, especially along its eastern margin. The most promising areas for geothermal exploration in the NW Red Sea-Gulf of Suez rift system are located where the eastern shore of the Gulf of Suez is characterized by superficial thermal manifestations includin...

Numerical simulation of a geothermal reservoir, modelled as a bottom-heated square box, filled with water-CO2 mixture is presented in this work. Furthermore, results for two limiting cases of a reservoir filled with either pure water or CO2 are presented. Effects of different parameters including CO2 concentration as well as reservoir pressure and temperature on the overall performance of the s...

Recent national focus on the value of increasing US supplies of indigenous renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well distributed nationally. A panel was assembled in September 2005 to evaluate the technical and economic feasibility of geothermal becoming a major supplier of primary energy for US base-load generation capa...

Two loud explosions accompanied by two successive big dark clouds that would have been 300 metres high, had taken place at El Humazo geothermal manifestation at February 2003. These explosions produced some important geomorphologic and structural changes that were registered in the geothermal area and its surroundings. Among these, it can be mentioned the reactivation of a geothermal manifestat...

The decay kinetics of the candidate tracers 1naphthalene sulfonate and 2,6-naphthalene disulfonate was studied under laboratory conditions that simulate a hydrothermal environment. Neither of the naphthalene sulfonates exhibited any thermal decay after one week at 330C, indicating that they are suitable for use in geothermal settings having temperatures of 330C or hotter. Both tracers were succ...