Australia is cross-cut by a number of major WNW-ESE trending lineaments which appear sometimes to be expressed at a local level by often subtle, discontinuous, fault systems or dykes or batholiths. Episodic movement starting in the west from the early Proterozoic of the tabular block between these major lineaments resulted in the development of progressively younger basins to the east. The Woodside Petroleum and SPIRT-funded research by Mr Falih Daim is designed to investigate the effect of Cretaceous-Tertiary faulting during sedimentation in the Northern Carnarvon basin.

 

 

This research has involved Mr Daim in the working up of a detailed biostratigraphic framework for the North Rankin and Goodwyn wells in the Northern Carnarvon Basin. From this a series of structural and isopach maps of the Upper Cretaceous - Lower Tertiary has been prepared for the same oil fields. Suitable subscene of the seismic, magnetic, gravity and bathmetric data available for the whole North West Shelf from our collaborators in AGSO have been worked up. The tectonic models arising from this research will be compared with those devised elsewhere for regions of similar tectonic setting (see Daim & Lennox 1998).

 

This research has important implications to petroleum exploration both in Australia and overseas where it appears that cross-structures have a far greater influence on basin development than has hither to been appreciated. As the NW Shelf is a frontier basin much can be gained in establishing in the literature through the results of this study the significant contribution of episodic, basin-normal faulting to the development of these plays. Such conclusions would have an influence on exploration in other extensional and transpression tectonic settings in the trailing edge of continental plates.