The block is about 130km north-west of Miri, Sarawak. According to Petronas, the F2 Attic-1 appraisal well, located in water depths of 91 metres, encountered "significant" gas accumulation in a limestone reservoir after reaching final TD of 2,400 metres below sea level.
"A single production test was conducted at the well, which resulted in a flow rate of 31 million standard cubic feet of gas per day, with 7% carbon dioxide and 35ppm hydrogen sulphide," the company said.
"We wouldn't be able to tell the extent or magnitude of the reserves from this find without further appraisals," a Petronas official told Reuters.
The F2 Attic field is adjacent to the B11, B12 and F38 fields, which provide natural gas to the Bintulu LNG complex. The facility has three plants which house eight production trains capable of producing a total of 23 million tonnes of LNG per annum.