Session 8. Oral Presentation for: Play analysis in the onshore Otway Basin, South Australia

Presented on 27 May 2025: Session 8 The Otway Basin is one of the best-known Mesozoic rift basins that span the southern coastline of Australia. The onshore portion of the basin covers nearly 10,000 km2 in South Australia (SA), from which both oil and gas have been produced. In 2023, the Department for Energy and Mining conducted an integrated geological, chemostratigraphic, geochemical and geophysical study, which identified intervals of potential hydrocarbon source rocks as well as potential suitable reservoirs, with the information used to prepare a petroleum systems model of the onshore Otway Basin in SA. The model showed significant hydrocarbon generation in the Penola Trough as expected, but also, for the first time, it appears that significant hydrocarbons may have been generated and expelled in the lightly explored Robe and Tantanoola Troughs. Subsequently, the Geological Survey of South Australia conducted play analysis of eight potential hydrocarbon reservoir intervals in the region, to understand the distribution of reservoirs, seals, mature source rocks and potential hydrocarbon migration pathways, to aid hydrocarbon exploration in the region. This process required review of the initial gross depositional environment mapping, with iteration further highlighting prospectivity; the Casterton Formation is presented as an example. Maps for the Lower Sawpit Shale are presented as an example of the play analysis process. To access the Oral Presentation click the link below. To read the full paper click here