Coastal Energy has announced appraisal drilling success from the Oligocene and Eocene reservoirs at the Songkhla field located in the Gulf of Thailand.

The Songkhla A-09 well was drilled to 8,109ft true vertical depth and encountered 140ft of net pay in the Lower Oligocene Wedge reservoir with average porosity of 15%.

Besides, the well has encountered 75ft of net pay in the underlying Eocene reservoir analogous to that seen in the Songkhla A-07 well, which had 16.5% porosity and initially flow tested 1,100bopd.

The A-09 well also pushed down the lowest known oil in the Eocene by 105ft, and is approximately 330ft up structure from the Songkhla A-08 well in the Lower Oligocene.

Prior to the A-09, the Songkhla A-08 well was the easternmost well on the structure, which supported the existence of the Lower Oligocene Wedge.

Pressures in the A-09 approximate the original reservoir pressure at Songkhla Main, indicating that there has been no depletion of the Lower Oligocene Wedge from the Main reservoir.

The company has now spudded the Songkhla A-12 well to further appraise the Lower Oligocene Wedge.