Geohazards in geothermal exploitation

Abstract

Geohazards need to be taken into account in harnessing of geothermal areas. This applies in particular to the high temperature type which is in one way or another related to volcanic or intrusive centres. The issues to be regarded include the type and history of volcanism, definition of segments with most active fault movements, earthquake activity including microseismicity, slope stability and possibility of flash floods. Gas fluxes from magma chambers or intrusive activity may cause corrosion problems of production wells. In geothermal systems of restricted recharge drawdown of the reservoir fluid causes thickening of the overlying steam zone and increased surface geothermal activity. Hazards involved with exploitation of low and high temperature geothermal systems where hosted in sedimentary or thick pyroclastic deposits having limited recharge may cause ground subsidence and damage to buildings and roads.