Modelling in Geothermal Exploration

Abstract

In geothermal studies we often have to draw conclusions and make decisions using uncertain or incomplete data sets. In such circumstances, we are compelled to rely on ‘modelling’. Modelling takes many forms and is used for many purposes, from temperature prediction to cash flow prediction. Equations typically modelled in geothermal studies include the heat flow equation, phase change equations, fluid dynamics equations, Rayleigh number equations, project valuation equations or hydro-geo-mechanical equations. Models of geothermal systems are often constrained by geophysical measurements, observations of structural trends, geochemical signatures, flow rate observations, or temperature measurements. Thermal modelling sheds light on probable temperatures at depth prior to expensive drilling. Reservoir modelling, likewise, helps predict the performance of future geothermal production wells, with increasing confidence as reservoir properties are constrained. Economic modelling, however uncertain, is essential to make informed investment and project development decisions.