UNOCAL TESTS DISCOVER OFF EAST KALIMANTAN

Improved technology has yielded an oil and gas discovery for Unocal Indonesia Ltd. The company, as operator for Indonesia's state owned Pertamina, scored the strike in a production sharing contract area off East Kalimantan. Unocal drilled its 2 Serang discovery in 335 ft of water about 10 miles north of Attaka field, which has produced 450 million bbl of oil and 750 bcf of gas.

Jan. 28, 1991

2 min read

Improved technology has yielded an oil and gas discovery for Unocal Indonesia Ltd.

The company, as operator for Indonesia's state owned Pertamina, scored the strike in a production sharing contract area off East Kalimantan.

Unocal drilled its 2 Serang discovery in 335 ft of water about 10 miles north of Attaka field, which has produced 450 million bbl of oil and 750 bcf of gas.

The well, drilled to 12,500 ft measured depth, cut 102 ft of oil sand and 500 ft of gas sand in Upper Miocene. Drillstem tests of three oil zones at 7,300-8,488 ft, totaling 60 ft of perforated pay, yielded a maximum combined flow of 12,034 b/d of oil and 23.63 MMcfd of gas through various chokes.

The 2 Serang lies 5,500 ft east of Unocal's 1 Serang. The latter logged 20 ft of oil pay and 57 ft of gas pay. Unocal ran three drillstem tests in the No. 1 well in a stratigraphic interval similar to the one tested in 2 Serang. Combined flow rates were 1,636 b/d of oil and 9.8 MMcfd of gas.

The 1 Serang was considered uneconomic and abandoned in 1973. However, advances since that time in geophysics, geology, and completion techniques led to the improved results.

Drilling of further Serang delineation wells is to begin immediately.

Unocal Indonesia, a wholly owned subsidiary of Unocal Corp., holds a 100% working interest in the contractor's share of production from the East Kalimantan contract area after cost recovery.