Reservoirs geothermal systems

Temperature of each reservoir was estimated from the assemblage of hydrothermal alteration minerals and temperature of alteration zone in active geothermal system (e.g., Hayashi, 1973 Takeno et al., 2000). 

The Okuaizu geothermal system is characterized by high temperatures (maximum 340°C), high salinity (about 2 wt% total dissolved solids (TDS)) and large amounts of non-condensable gases (1 wt% CO2 and 200 ppm H2S). The pH of the hydrothermal solution measured at 25°C is 6.44 (Table 2.6). However, the pH of the original fluid in the reservoir is computed to be 4.05. This pH as well as alkali and alkali earth element concentrations are plotted near the equilibrium curve of albite, K-mica, anhydrite and calcite (Fig. 2.19) (Seki, 1991). 

Fournier, R.O. (1981) Application of water geochemistry to geothermal exploration and reservoir engineering. In Ryback, L. and Muffler, L.J.P. (eds.). Geothermal Systems Principles and Case Histories. New York Wiley, pp. 109-143. 

Pruess, K. 2006. Modelling brine-rock interactions in an enhanced geothermal system deep fractured reservoir at Soultz-Sous-Forets (France) a joint approach using two geochemical codes frachem and toughreact. Lawrence Berkley National Laboratory, University of California. 

One of the main applications of hydrogen and oxygen isotope thermometry in geochemistry is the estimation of the reservoir temperatures of active geothermal systems or the evaluation of the ruling T conditions during deposition or alter-... 

Rojas, J., Menjos, A., Martin, J. C., Criaud, A. Fouillac, C. 1987. Development and exploitation of low enthalpy geothermal systems example of the Dogger in the Paris Basin, France. In Proceedings of the 12th Workshop on Geothermal Reservoir Engineering, Stanford University, 203 -212. 

The development of a residual liquid plume in the geothermal reservoir at Larderello requires further studies because, for example, the data shown in Fig. 12 may not result from the attainment of full equilibrium by produced gases, but rather by the addition of meteoric Ar to the geothermal system. Problems may arise from possible buildup of liquid plumes inside the reservoir, which could reduce secondary heat recovery. Should this happen, the re-injection pattern will be changed the injection in the well responsible for the plume buildup must be... 

Genter, A., Evans, K., Cuenot, N., Fritsch, D. Sanjuan, B., 2010. Contribution of the exploration of deep crystalline fractured reservoir of Soultz to the knowledge of enhanced geothermal systems (EGS). Comptes Rendus Geoscience, 342, 502-516. 

Hulen JB (1991) Assessing the role of active and ancient geothermal systems in evolution of oil reservoirs in the Basin and Range province, eastern Nevada. In Sedimentary... 

Durst, P. Vuataz, F. D. 2001. Geochemical modeling of the Soultz-sous-Forets Hot Dry Rock system, brine rock interactions in a deep hot fractured granite reservoir. 26th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, SGP-TR-168. 

For heat pumps based on flooded mine systems, where the heat abstracted is replenished seasonally by inputs from solar radiation and geothermal gradient, the longevity of the reservoir is, in principle, limitless. The sustainability of the operation will only be limited by the durability of the infrastructure (e.g., biofouling, clogging or physical instability of boreholes, longevity of collector coils). 

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