Gas Geothermometry In Selected Icelandic Geothermal Fields With Comparative Examples From Kenya
Journal Article: Gas Geothermometry In Selected Icelandic Geothermal Fields With Comparative Examples From Kenya
AbstractUsing data from selected geothermal fields in Iceland, several gas geothermometers are applied to calculate reservoir temperatures. Results for well fluids are compared to estimated inflow temperatures. The effects of gases from other sources, e.g. magmatic fluid entering reservoirs, condensation/boiling, loss of components and mixing of different fluids during upflow, are discussed. Those geothermometers that give results reasonably close to the inflow temperatures, and are not constrained by the need to know thermodynamic parameters, are used to estimate subsurface temperatures from fumarole steam composition. It is suggested that geothermometers based on H2 and H2S concentrations are relatively effective. The CO2, H2S and H2 geothermometers are also evaluated by thermodynamic simulation using plausible mineral buffers. The CO2 geothermometer generally gives slightly low temperatures for values in the range 100-200°C. The calibration of the existing H2S and H2 geothermometers needs improvement when reservoir temperatures are higher than 220°C. The mineral buffer controlling H2S in reservoirs seems to be pyrite + magnetite + epidote + prehnite changing into pyrite + pyrrhotite + epidote + prehnite with increasing temperature.
- Zhao Ping and Halldor armannsson
- Published Journal
- Geothermics, 1996
- Not Provided
Check for DOI availability: http://crossref.org
Zhao Ping,Halldor armannsson. 1996. Gas Geothermometry In Selected Icelandic Geothermal Fields With Comparative Examples From Kenya. Geothermics. (!) .