Convective geothermal systems

Convective geothermal systems have been classified as volcanic (also termed high-temperature or high-enthalpy) and non-volcanic (low-temperature or low-enthalpy). By definition, high-71 systems have temperatures of >180 CC... 

M. Combamous, Natural Convection in Pbrous Media and Geothermal Systems, Proc. 6th Int. Heat Transfer Conf, vol. 6, pp. 45-59, Hemisphere Publishing, Washington, DC, 1978. 

Fig. 10 Schematic illustratimi of seismogenic tensile cracking by thermal stresses caused by convective cooling of rocks at the heat source of a geothermal system (From Foulger 1988)...

Direct uses of geothermal heat are very varied. They are largely based on exploitation of low-enthalpy convection systems. Uses include balneotherapy, space heating, and many agricultural and industrial uses. The potential use of geothermal resources is dictated by fluid temperature as described by the Ltndal diagram (Fig. 1). 

Many geological flows such as flow in an oil reservoir or in a geothermal power system involve convective heat transfer in a porous medium. 

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