Unocal develops fields in Ganal, Rapak, Makassar Strait PSCs off Indonesia

Aug. 3, 2004
Unocal Corp. subsidiaries have a number of development activities under way off Indonesia, including Phase I development of Gendal field in the Ganal production-sharing contract area, Gehem-3 and Ranggas-7 appraisal well completions in the Rapak PSC, and development activities in the West Seno field in the Makassar Strait PSC area.

By OGJ editors

HOUSTON, Aug. 3 -- Unocal Corp. subsidiaries have a number of development activities under way off Indonesia:

Unocal and its 20% partner ENI SPA selected a development concept to submit to the government later this year for phase I of Gendalo field in the Ganal production-sharing contract (PSC) area, operated by Unocal Ganal Ltd. Eni-Ganal Ltd. holds 20%. Final engineering design will begin immediately. Phase I, targeted for startup in 2007, will be designed to produce 250-300 MMscfd.

Gehem and Ranggas
New 3-D seismic acquisition is under way in the Rapak PSC across Gehem and Ranggas deepwater fields, which may be developed jointly using a common host facility. The development study and engineering are in process. Unocal expects to submit a development plan in 2005.

Meanwhile Unocal Rapak Ltd. has completed drilling operations at the Gehem-3 and Ranggas-7 appraisal wells in the Rapak PSC. Its 20% partner is Eni-Rapak Ltd.

Unocal drilled Gehem-3 to 16,424 ft TD in 5,744 ft of water. The well encountered 232 ft of net gas pay and 8 ft of net oil pay. Well results indicate consistent reservoir pressure across the entire primary reservoir pool in this field and a potential single hydrocarbon pool with high-quality reservoir rock, Unocal said.

The Ranggas-7 well was drilled to 14,402 ft TD in 5,394 ft of water. A total of 167 ft of net pay was encountered, including 52 ft of oil. Ranggas-7 was drilled to delineate the downdip and eastern limits of the primary Ranggas development area and to penetrate the deeper primary reservoir unit of the field. The well did not encounter hydrocarbons in the deeper zone, but in the shallower zone, hydrocarbons were penetrated as far as 400 ft downdip of Ranggas-1.

West Seno field
The West Seno field, which Unocal Makassar Ltd. operates in the Makassar Strait PSC area about 118 miles northeast of Balikpapan in, currently has 20 wells completed, with gross production averaging 24,000 boed in June, a 7,000 boed increase from April. By yearend 26-28 wells are expected to be on line with a gross exit rate of 25,000-35,000 boed.

Recently opened bids for Phase 2, including tension leg platform fabrication and offshore installations, were deemed unacceptably high. Cost-reduction options are being considered, and construction will extend beyond 2005.

Unocal Makassar has a 90% working interest and Indonesia's state-owned oil and gas company Pertamina Upstream holds the remaining 10%.