Effects of Hydrothermal Chemistry on Reservoir Evolution

Abstract

Although the corrosion and scaling problems associated with handling geothermal fluids are well known, the effects of hydrothermal reactions are often overlooked in geothermal reservoir modeling. Waterrock chemistry can be expected to affect the evolution of a reservoir in at least three ways: (a) the heats of reaction may contribute directly to the energy production, (b) the viscosity and thermodynamic properties of water are affected by the dissolved solids--this is especially important in two-phase regimes, and (c) the porosity and permeability change with time due to dissolving and precipitation as well as due to the volume change associated with alteration.