This permit, having an area approximately 5,983 km2, is located on the western flank of the Queensland portion of the Cooper Basin. The Ballera-Mt. Isa gas pipeline traverses the northeastern portion of the permit. Structurally the Permit is dominated by a large anticlinal high known as the Curalle Anticline. This anticline trends roughly north-south and extends into the adjacent ATP 549 permit. The Permit lies west of the Permian pinchout edge and as such the sedimentary section is dominated by the Jurassic and Cretaceous aged Eromanga Basin.
Regionally, the permit is considered to be located in a very strategic setting, because any hydrocarbons generated in deeper areas, such as the Arrabury Trough to the south and south west and the Windorah Trough to the east, would have migrated up through the carrier (reservoir) beds towards the Curalle Anticline, a regional high which dominates this permit. Supporting this is the presence of the producing Inland Oilfield together with numerous shows found in wells drilled in and around the area.
Several of the regional wells previously drilled have intersected numerous hydrocarbon shows within the Jurassic section. The current thinking is that these wells were not located optimally; the chosen drilling locations are considered by current standards not to have been sufficiently well delineated by seismic. Curalle-1 is a case in point. Drilled during the 1980’s to test the potential of the Curalle Anticline, the well failed to encounter commercial quantities of hydrocarbons. However the recovery of a minor amount of condensate film within the Adori Sandstone did provide evidence that hydrocarbons have migrated onto the Anticline.
Enterprise acquired an interest in ATP 539 through a farmin with Great Artesian Oil and Gas Limited in 2004. As part of that farmin agreement Enterprise Energy acquired the 89 km Planet Downs 2D seismic survey in 2004. That survey, covered the crestal part of the regional Curalle Anticline. One of its aims was to find a higher point on the structure to that tested by the previous Curalle-1 well. Several other structural targets were also delineated including the Planet Downs Lead located along trend and further to the south.
