The Wei 12-7-1 well is in 30 metres of water and is located 2 km north of the Wei 12-8-1 discovery well. It is expected to take 10 days to drill, log and evaluate the well.

Total depth is expected to be around 1,700 metres and Roc's experts are predicting recoverable reserves from the entire Wei 12-7 prospect of around tens of millions of barrels.

Once the operations on Wei 12-7-1 are completed, Roc Oil will proceed to drill an appraisal well at Wei 12-8-3, which should also take around 10 days to drill. This well - and the entire Wei 12-8 prospect - is expected to have recoverable reserves of between 20 to 30 MMBO.

Should both wells prove to be successful, Roc intends to drill three more back-to-back wells. It has made provision for this in its drilling schedule. A fourth and fifth well would only be dug should results of the additional wells prove to be "very compelling".

The Block 22/12 is a joint venture between Roc Oil (the operator with a 40% stake), Horizon Oil (30%), Petsec Energy (25%) and Oil Australia Pty Ltd (5%). However, in the event of a commercial development at the Block, the interest of the joint venturers will be reduced pro-rata should China's China National Offshore Oil Corp exercise its rights to participate up to 51% equity level.