Play analysis in the onshore Otway Basin, South Australia
Paul Strong A * , Chris Cubitt A , Tim Rady B , Rob Kirk C and Sharon Tiainen AA
B
C
Paul Strong is a geologist with 40 years of oil and gas experience, having graduated with a BSc (Hons) in Geology from the University of Durham (UK) and an MSc in Petroleum Exploration Studies from the University of Aberdeen (UK). He is Chief Petroleum Geologist at the SA Department for Energy and Mining in Adelaide, after holding a range of senior technical and managerial positions with Santos Limited for nearly 23 years. He is a member of PESA and AAPG. |
Dr Chris Cubitt graduated from the University of Adelaide with a PhD in Clastic Diagenesis and Sedimentology. He has more than two decades of industry experience in reservoir and regional geology working basins worldwide. In 2023 he joined South Australia’s Department for Energy and Mining and is Head of the Basin Prospectivity team. Chris is the author of more than 20 publications, and is a member PESA, IAS and EAGE. |
Tim Rady is a geophysicist with 18 years’ experience in the oil and gas industry, specialising in seismic interpretation, play analysis, prospect maturation and opportunity evaluation. He has worked for Santos, Premier Oil and TotalEnergies on a broad range of new ventures, exploration and development projects across the globe. Tim currently consults to the E&P industry and is the technical subsurface lead for entX Limited’s underground hydrogen storage project. Tim holds a BSc (Hons) in Petroleum Geophysics from the Australian School of Petroleum and an MBA from London Business School. |
Rob Kirk graduated from the University of Adelaide (BSc Hons) and the University of WA (MSc), combining geology with geophysics. He has five decades of industry experience in seismic and sequence stratigraphy having worked some 40 basins worldwide. Rob has given public and inhouse industry courses on seismic stratigraphy for 30 years. Rob jointly won the 1991 AAPG Best Paper Award, was the 1993 and 2014 PESA Distinguished Lecturer, the 1994 Keynote Speaker at GCSSEPM, Houston, and has had regular articles in the PESA Journal. He is a member of PESA and AAPG. |
Sharon Tiainen is a graduate of the University of Adelaide and has an Honours Degree in Petroleum Geology and Geophysics. She has over 25 years of global experience in the upstream oil and gas industry having worked in exploration, appraisal, development and production roles. In 2009 she established her own company, and most recently she joined the South Australia Department for Energy and Mining as a Principal Geologist. She is a member of EAGE, SPE and PESA. |
Abstract
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.
Keywords: Casterton Formation, gross depositional environment (GDE), iteration of interpretation, Lower Sawpit Shale, Otway Basin, petroleum, play analysis, South Australia.
Paul Strong is a geologist with 40 years of oil and gas experience, having graduated with a BSc (Hons) in Geology from the University of Durham (UK) and an MSc in Petroleum Exploration Studies from the University of Aberdeen (UK). He is Chief Petroleum Geologist at the SA Department for Energy and Mining in Adelaide, after holding a range of senior technical and managerial positions with Santos Limited for nearly 23 years. He is a member of PESA and AAPG. |
Dr Chris Cubitt graduated from the University of Adelaide with a PhD in Clastic Diagenesis and Sedimentology. He has more than two decades of industry experience in reservoir and regional geology working basins worldwide. In 2023 he joined South Australia’s Department for Energy and Mining and is Head of the Basin Prospectivity team. Chris is the author of more than 20 publications, and is a member PESA, IAS and EAGE. |
Tim Rady is a geophysicist with 18 years’ experience in the oil and gas industry, specialising in seismic interpretation, play analysis, prospect maturation and opportunity evaluation. He has worked for Santos, Premier Oil and TotalEnergies on a broad range of new ventures, exploration and development projects across the globe. Tim currently consults to the E&P industry and is the technical subsurface lead for entX Limited’s underground hydrogen storage project. Tim holds a BSc (Hons) in Petroleum Geophysics from the Australian School of Petroleum and an MBA from London Business School. |
Rob Kirk graduated from the University of Adelaide (BSc Hons) and the University of WA (MSc), combining geology with geophysics. He has five decades of industry experience in seismic and sequence stratigraphy having worked some 40 basins worldwide. Rob has given public and inhouse industry courses on seismic stratigraphy for 30 years. Rob jointly won the 1991 AAPG Best Paper Award, was the 1993 and 2014 PESA Distinguished Lecturer, the 1994 Keynote Speaker at GCSSEPM, Houston, and has had regular articles in the PESA Journal. He is a member of PESA and AAPG. |
Sharon Tiainen is a graduate of the University of Adelaide and has an Honours Degree in Petroleum Geology and Geophysics. She has over 25 years of global experience in the upstream oil and gas industry having worked in exploration, appraisal, development and production roles. In 2009 she established her own company, and most recently she joined the South Australia Department for Energy and Mining as a Principal Geologist. She is a member of EAGE, SPE and PESA. |
