New heat flow data aids exploration in the Canning Basin, Western Australia

Abstract

The Geological Survey of Western Australia (GSWA) is providing new heat flow data and continuing studies in subsurface temperatures to understand the origin, migration and accumulation of geofluids in petroleum and geothermal systems of the Canning Basin. The study includes an investigation of subsurface temperatures from 274 wells, thermal conductivity measurement of 50 core samples from 22 wells, and single-dimensional (1D) heat-flow modelling of 101 wells. Thermal conductivity measurement of Canning Basin formations range from 1.06–5.83 W/mºC and modelled surface heat-flow ranges from 20–160 mW/m². The lowest measured thermal conductivity is in the Ordovician Goldwyer Formation at 1.06± 0.28 W/mºC, and the highest values are in the Upper Carboniferous Reeves Formation at 5.83 ± 0.22 W/mºC.

Generally, estimated heat-flow values are lower where thick sedimentary deposits are present such as the Fitzroy Trough, Lennard Shelf, and Kidson Sub-basin, with values less than 65 mW/m². The heat flow values increase to over 80 mW/m² on the Broome Platform and Jurgurra, Mowla and Barbwire terraces. Lower heat-flow values have been modelled in West Blackstone–1 (47 mW/m²), Curringa–1 (52 mW/m²), Kennedia–1, Napier–2 and Pearl–1 (55–52 mW/m²). Higher heat-flow values have been modelled in Goodenia–1, Lovells Pocket–1, Kanak–1, Cudalgarra North–1, and Cudalgarra–1, where heat-flow values are over 100 mW/m². These new thermal conductivities, corrected temperatures, and heat-flow values support improved modelling of the Canning Basin petroleum and geothermal systems.