Unocal confirms Indonesian deepwater strike

Unocal's east Kalimantan oil/gas strike [159,874 bytes] Unocal Indonesia Co. has gauged a large flow rate in a deepwater step-out off East Kalimantan, Indonesia. The Merah Besar 5 well flowed at a rate of 9,430 b/d of oil and 7.4 MMcfd through a 11/8-in. choke with flowing tubing pressure of 900 psi from a single zone at 11,120 ft TMD. Additional oil and gas zones were confirmed but not tested, said Unocal.

March 2, 1998

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Unocal's east Kalimantan oil/gas strike [159,874 bytes]

Unocal Indonesia Co. has gauged a large flow rate in a deepwater step-out off East Kalimantan, Indonesia.

The Merah Besar 5 well flowed at a rate of 9,430 b/d of oil and 7.4 MMcfd through a 11/8-in. choke with flowing tubing pressure of 900 psi from a single zone at 11,120 ft TMD. Additional oil and gas zones were confirmed but not tested, said Unocal.

The delineation well is in 1,664 ft of water off the Mahakam Delta, about 1.8 miles west of the Merah Besar 6 discovery well, drilled last September (see map). The discovery well flowed 24.8 MMcfd of gas and 860 b/d of condensate from a zone at 8,553 ft TMD.

The No. 6 well tested two other zones that flowed at a combined rate of 980 b/d of oil.

Further delineation

Unocal's Merah Besar 7 well confirmed the presence of hydrocarbons but flow rates from the oilsands were subcommercial. The well was abandoned without testing.

Merah Besar Wells 5 and 7 are in the East Kalimantan production-sharing contract (PSC) area. Unocal is operator and holds a 100% interest in the PSC area.

So far, eight of Unocal's 12 deepwater wells in Indonesia have been successful.

The company plans to drill two more delineation wells in Merah Besar. The first of these is drilling ahead 1.8 miles north of Merah Besar 5.

In June, after interpretation of 850 sq miles of newly acquired 3D seismic data, Unocal plans to drill as many as three more delineation wells on the eastern part of the Merah Besar structure.

Other Indonesia activity

Elsewhere in Indinesia, Unocal plans to begin exploration drilling on the southern Makassar Strait contract area Mar. 1. Three planned wells, which will test large structures identified by 2D seismic, are considered higher-risk exploration opportunities.

Unocal and Mobil Makassar Inc. each have a 50% working interest in the Makassar Strait PSC.

Meanwhile, another Unocal subsidiary, Unocal Ganal Ltd., has signed a new PSC with Indonesian state oil firm Pertamina for 1.2 million acres in deep water off East Kalimantan. The Ganal PSC, also in the Mahakam Delta, is east of the southern portion of the Unocal/Mobil Makassar Strait PSC.

Operator Unocal Ganal 90% said 2D seismic acquisition is under way, and an exploration well is planned in 1999.

This is Unocal's fourth PSC in Indonesia in the past 6 months. Unocal and its partner in the Ganal PSC, P.T. Nusamba Energy Pratama 10%, qualified for a 35% after-tax share of oil production.

Unocal plans to drill a total of 38 exploration wells on deepwater prospects off East Kalimantan this year.