Publication Name: The Cooper & Eromanga Basins Australia
Authors: C.C. Yew and A.A. Mills
Date Published: June 1989
Number of Pages: 35
Reference Type: Book Section
Abstract:
Exploration efforts in PELs 5 and 6 in South Australia and in ATP 259P in Queensland have been directed traditionally towards the search for gas in the Permian Cooper Basin and for oil in the overlying Jurassic Cretaceous Eromanga Basin. These efforts have resulted in the discovery of a large number of gas fields and a fewoil fields in the Cooper Basin and a large number of predominantly small oil fields and a few gas fields in the
Eromanga sequence.
As Jurassic prospects decrease in size and number with increasing exploration maturity, a more concerted exploration effort should be directed towards the Cooper Basin section in the search for oil as significant potential for undiscovered oil exists in the Permian there. The authors' belief stems from the widespread occurrence of oil in several Permian formations and the existence of commercial production of Permian oil in several fields, the discoveries of very liquids-rich Permian gas which suggest the possibiliry of downdip oil legs, and increasing geologic evidence to support the hypothesis that a significant portion of the discovered Jurassic oil was sourced from the underlying Permian section. Hence, the Permian section could provide oil exploration targets where the oil has beenpartially or totally unable to migrate up into the overlying Eromanga section.
Until recently, little emphasis has been placed on the search for Permian oil. The search has proved a difficult
challenge in that attempts to explore for, delineate and produce Permian oil accumulations have been frustrated by unfavourable stratigraphic, reservoir and fluid characteristics. Despite these difficulties, the discovery of potentially large Permian oil fields within a liquids-rich corridor near the Basin margin and along the main structural trends is possible.