This month, PESA QLD is delighted to bring you a presentation from Mr David Lowry. Mr Lowry has been a familiar face at many PESA functions over the years, having previously taught at PESA sponsored short-courses and presenting at PESA technical lunches.
This month, Members are lucky enough to hear David’s insights into structuring and hydrocarbon generation within the Eromanga Basin. This talk is the culmination of many years of research, and Members with a keen interest in innovative exploration strategies are sure to learn from David’s wealth of knowledge.
The Technical Lunch will be held at the Brisbane Hilton Hotel, in the “Victoria’s Room” with access from the Hilton Main Foyer on level 6.
Peak generation of oil in the Eromanga Basin happened in the Cretaceous – around 90 Ma. But the basin has since undergone regional warping and stripping prior to the Eocene, followed by local compressional folding in the Miocene. Modern structure is thus a poor guide to migration at peak generation.
Careful manipulation of sonic logs allows stripping estimates leading to structure maps restored to maximum Cretaceous burial. These maps allow determination of drainage areas and routes.
Maturity modelling of wells reveals the location of kitchens and suggests rough estimates of volumes expelled. Previous publications of maturity maps and models have largely neglected the evidence for stripping and the models are a poor basis for exploration. The location of kitchens is not restricted to areas of current deep burial. For example the enigmatic oil occurrence at Corona-1 comes from a small shallow Birkhead kitchen made mature by 700 m of former extra burial and a very high heat flow.
The work has the potential to inspire further exploration by reducing charge risk of prospects in areas presently neglected.