Beetaloo gas, hydrogen and geothermal resources – insights from 3D basin modelling

The Beetaloo Sub-basin hosts a large proven shale gas resource, and this study demonstrates the opportunities for other low-emission energy sources including geothermal energy and natural hydrogen. CSIRO has developed a 3D basin model that predicts reservoir rock properties, pore pressure, composition of hydrocarbons and gas capacity of the Velkerri and Kyalla shales. Kinetic modelling also demonstrates that where Velkerri shale is overmature for hydrocarbons it potentially generated significant amounts of free molecular hydrogen. However, the proportion of this hydrogen currently preserved in the basin is unknown. The model also reveals considerable temperature anomalies around specific structural domains with heat flow up to 100 mW/m−2, and these are likely associated with radiogenic basement lithologies. These thermal domains are targets to further investigate geothermal and natural hydrogen resource potential in the Beetaloo Sub-basin.