Using Mineral and Petroleum Exploration Data for Geothermal Exploration in Australia

Geothermal energy is receiving increasing attention as a potentially abundant, large scale, cost competitive, base load, safe and low-emission energy source for electricity generation and industrial applications in Australia. Geothermal resources comprise a volume of rock of suitable temperature and permeability, and a heat-transport fluid. High crustal temperatures in Australia are thought to be generated by high heat producing granites being overlain by thermally insulating sediments. Two types of geothermal plays exist in Australia: Hot Rocks, which require reservoir enhancement and possibly the addition of water; and Hot Sedimentary Aquifers in shallow (<3,500 m), permeable, water-saturated sediments. Ground selection by early Australian geothermal explorers was made based on direct temperature measurements from deep (<5 km) petroleum wells. In areas without previous deep drilling, the most robust measurement for predicting temperature at depth for Hot Rock geothermal resources is heat flow, but there are only similar to 150 publicly-available measurements continent-wide. Targeting for Hot Rock geothermal resources is increasingly being done using other geological datasets acquired for minerals exploration. These datasets include geological maps (lithology, stress, structure), seismic, geochemistry, gravity, radiometrics and magnetics. Heat flow measurements are used in petroleum studies and can be of use in exploration for some types of mineral deposits.