Thai Miocene delivers again for Coastal

Offshore staff

HOUSTON -- Coastal Energy has discovered more oil with its latest well on the Bua Ban field in the Gulf of Thailand.

Bua Ban North A-04 well was drilled to TVD 6,417 ft (1,956 m) to test Miocene and Upper Oligocene targets in an upthrown block, west of the A-01 discoveries. It encountered 22 ft (6.4 m) of net pay in the Miocene interval, with average porosity of 29%.

The reservoir is in a fault block separate from A-01. Coastal estimates in-place oil at around 6 MMbbl.

The well also encountered 11 ft (3.3 m) of net sand with shows in a deeper Miocene section with 22% average porosity, and 10 ft (3 m) of net sand with shows in the Upper Oligocene with 25% porosity. However, these two zones could not be tested due to the well’s high angle. Coastal adds that it will not be able to assess the productivity of the deeper Miocene and Upper Oligocene zones until mid-May, when a flow test should get under way, using a newly commissioned MOPU.

CEO Randy Bartley said: “We continue to encounter shallow Miocene pay zones with excellent porosity and reservoir characteristics. We plan to begin targeting the recently discovered zones with horizontal wells to maximize production from each well.

“The original Miocene vertical test well at Bua Ban continues to produce over 200 b/d with zero water cut. This strong performance combined with recent drilling success in the Miocene supports our conclusion that the shallow Miocene is a viable target on the western side of the Songkhla basin. We believe that it could prove to be a very prolific play if exploited using horizontal wells.”

04/08/2011