Publication Name: Eastern Australian Basins Symposium V (EABS 2015)
Authors: Louise Munro, Kevin Hill, Ruth Wightman
Date Published: September 2015
Number of Pages: 8
Abstract:
The Kutubu Field in the jungle-covered mountains of PNG, comprises the Hedinia Anticline containing mainly gas and the oil-bearing Iagifu Anticline. Together they hold significant reserves of gas and have produced well over 300MMBBL oil from a basal Cretaceous Toro Sandstone reservoir overlain by 1 km of Cretaceous shale and 1 km of karstic Miocene limestone. Over 70 wells and sidetracks have been drilled but there are only 8 2D seismic lines, all of which are of poor quality. In 2D, sequential balanced cross-sections along seismic lines were constructed and revealed that the structure formed as a large detachment fold cored by the Jurassic syn-rift facies of a pre-existing half-graben. This was then cut by forethrusts and backthrusts making a popup structure with hydrocarbon reserves both in the gently folded hangingwall and the separate 1 km vertical forelimb. A 3D model was constructed of the hangingwall revealing the many small faults that compartmentalise the structure.