During September 2012, Karoon entered into a farm-in agreement to acquire 100% of early stage exploration permit WA-482-P in the Carnarvon Basin offshore north Western Australia.
The Carnarvon Basin is one of Australia’s largest and most prolific oil and gas regions. The basin is host to multiple world scale LNG projects, a number of oil projects and is also a region being actively explored by major international oil companies.
While in a relatively underexplored part of the Carnarvon Basin, the permit covers a significant area and straddles Jurassic depocentres (Wigmore Sub-basin and Whitetail Graben). Good quality oil mature source rocks seen in nearby wells are interpreted to be present over large parts of the permit. Successful drilling results would open up new exploration plays in the Basin.
The permit is located approximately 280 kilometres north of Karratha in water depths ranging between 400 to 2,000 metres and covers an area of 13,539 square kilometres.
During May 2014, Karoon farmed out a 50% equity interest in the permit to Apache Northwest Pty Ltd (‘Apache’), part of Quadrant Energy Australia Ltd. As part of the farm-out, Karoon was carried for 90% of the cost of the Levitt-1 exploration well and received US$9 million in back costs.
Equity interest of the participant in WA-482-P are:
|Karoon Gas (FPSO) Ltd||50%|
|Quadrant Energy Australia Ltd (Operator)||50%|
The exploration program is focused on testing the presence of a working petroleum system interpreted to be generating oil from the mature early Jurassic Wigmore Sub-basin and Whitetail Graben source kitchens, targeting structures positioned to receive migrating oil or wet gas from these kitchens.
These areas contain a significant thickness of Jurassic source rocks of the same age and nature, known to charge petroleum accumulations elsewhere in the Basin. The exploration program is designed to evaluate reservoirs in the deeper North Rankin and the shallower Legendre formations.
In addition to the licensed and reprocessed historical 3D and 2D seismic data, and the acquisition of the Chrysalids 3D seismic survey during 2015, the joint venture licensed 5,256 square kilometres of the Polarcus multi-client Capreolus 3D seismic survey within the permit area.
Following the acquisition of the Capreolus 3D seismic data, the joint venture now has high quality 3D data covering over 75% of the entire permit area which will be used to better define, risk and rank identified prospects and leads.
The Levitt-1 exploration well was drilled in the permit during August 2015 reaching a TD of 4,929 mRT. Levitt-1 intersected good quality reservoir sands in both Legendre and North Rankin formations however these were water bearing at this location. Good quality oil shows were recorded above the North Rankin formation with analysis proving that oil had migrated through the Levitt area.
The current work program consists of PSDM seismic reprocessing and geological and geophysical studies.
The main targets within WA-482-P are the North Rankin, the Legendre and the Intra-Mungaroo Formations. The acreage straddles 2 main depocentres with good quality oil mature Jurassic source rocks seen in nearby wells and interpreted to be present over large parts of the permit.
Clastic reservoirs are interpreted to be present in early formed traps and have received hydrocarbon charge from thick Triassic and Lower to Middle Jurassic source rocks in depocentres mainly in the north and east of the Permit. A key element of the work program is to identify prospects unbreached by structural events from late Jurassic onward.