3D Thermal Modelling Vs Down-Hole Temperature Extrapolation and the Implications for Targeting Potential Geothermal Anomalies: a Sydney Basin Case Study

Abstract

Geothermal exploration programs require accurate subsurface temperature information and currently this information primarily comes from temperature maps created from the extrapolation of shallow down-hole temperature measurements. These extrapolations are often taken from measurements made in non-equilibrated boreholes and do not account for variations in geological structure or thermal conductivity. Here we present a case study for the Sydney basin where we explore temperature maps at 5km created from extrapolated equilibrated and non-equilibrated borehole measurements and from modelled basin temperatures and the implications for targeting potential geothermal anomalies. The modelled temperatures are derived from finite element models using 3D basin geology and defined thermal properties.