Lundin Petroleum, Stockholm, plans to develop several fields in and off Tunisia in coming years.
Its Isis field in the Mediterranean has produced 6,000 b/d in recent months and could be larger than initially thought, the company said.
The field is on a 408 sq km concession, the southeastern tip of which is near Tunisia's maritime boundary with Libya (OGJ Online, June 19, 2002). Lundin Petroleum acquired Isis when it bought Coparex International BV in 2002.
Proved and probable reserves at Isis and onshore Sidi El Itayem fields total 3.2 million bbl, Lundin said.
The Isis-1 discovery well tested oil from the Cenomanian Isis limestone in 1974, and Isis-3 later flowed 11.5 MMcfd of gas, the operator said. The oil is produced into a floating production, storage, and offloading vessel. Nine wells have been drilled on the Isis structure.
A reprocessed, 102 sq km 3D seismic survey indicates that Isis field has a large northeast extension which a horizontal well could tap. This may provide significant upside to the field's reserves, the company said.
Interests in the Isis concession are Lundin 40%, Atlantis Technology Services 40%, and Tunisia's state ETAP 20%.
Other Tunisian fields
Lundin Petroleum also operates the Zelfa, Oudna, and Birsa concessions off northeastern Tunisia.
Fields on Oudna and possibly Birsa could be developed using the same FPSO moored at Isis, the company said.
The company is awaiting government approval of a development plan that covers 6-7 million bbl of reserves in Zelfa field and the southern part of AGIP SPA's Maamoura discovery. The companies are to evaluate joint development of the fields. Zelfa interests are Lundin Petroleum 62.5%, Atlantis 32.5%, and Klabzuba Oil & Gas, Fort Worth, 5%.
Oudna-1, a 1978 discovery, flowed a combined 7,000 b/d of 41° gravity oil from two intervals in Miocene Lower Birsa sandstone.
Original oil in place was estimated at 47.1 million bbl in three subblocks. 3D mapping also highlighted a significant undrilled accumulation in the hanging wall block south of Oudna-1. Lundin and Atlantis hold Oudna 50-50.
Birsa-1 was a 1976 discovery. Three wells flowed 724 b/d, 2,634 b/d, and 4,560 b/d, but interpretation of 1997 3D seismic data did not reduce the uncertainty on fluid contacts. Oil in place estimates therefore vary from 19 million bbl to 148 million bbl.
Onshore, Sidi el Itayem field produces 39° gravity oil. The field has some infill-workover potential in the main reservoir, Lower Eocene (Ypresian) nummulitic limestone at 2,400 m and significant upside in undeveloped, oil-bearing Middle Eocene Bartonian limestone.
Sidi Behara field has oil and gas potential in a Ypresian limestone reservoir and possible potential in deeper Cretaceous Abiod chalk.
CFTP, a 50-50 joint venture between Lundin and the government, operates Sidi el Itayem and Sidi Behara.