Cairn focus on CB-A-3 well for CB-OS/2 appraisal

Vol 6, PW 23 (29 Jan 03) Exploration & Production

CAIRN ENERGY is gearing up to begin a $30m appraisal programme at its CB-OS/2 concession in Gujarat.

It's scheduled to begin in February and consists of two 'firm' wells and one 'optional' well near the exploration well CB-A-3, which it drilled last April to a depth of 1,240 metres but later plugged and abandoned. Cairn now appears to be having a rethink about the prospectivity of the sands near CB-A-3.

We learn CB-A-3 was the third exploration well to encounter oil bearing sands in the Lakshmi area of CB-OS/2. It sits 2.6 km southwest of CB-A-2 and according to a source contains some of the "best developed oil-bearing sand section in the lower Tarkeshwar Formation to date." Cairn submitted a hydrocarbon discovery report to the DGH for the CB-A-3 discovery back in June in which it says it wants to focus on the Tli/h sands because they "hold the largest individual connected oil and gas volume" as well as the "largest gas cap" and because it is the thickest individual sand encountered so far "with the best petrophysical properties".

Cairn predicts productivity will be the highest for this sand but admits this has not been proved by drill stem tests. Cairn's core objective for the appraisal programme is to find out if the CB-A-3 discovery can be commercially exploited.

Alongside this it wants to broadly map the boundaries of the Lakshmi oil development area. Cairn estimates oil in place in the Tli/h sand at 80m barrels and gas in place at 10bn cubic feet.

If all goes well, Cairn wants to declare the field 'commercial' by September 2003.