Texaco Inc. and Marathon Oil Co. have marked progress on the $400 million Petronius compliant tower deepwater development project in the Gulf of Mexico.
Start-up is expected in January 1999. Production design capacity is 60,000 b/d of oil and 100 MMcfd of natural gas.
The field holds reserves estimated at an equivalent 80-100 million bbl of oil equivalent.
Operator Texaco and Marathon let major contracts related to the Petronius project to:
- J. Ray McDermott, Morgan City, La., fabrication yard, a $140 million contract for construction of the compliant tower for Petronius. McDermott also will handle installation of the entire structure. McDermott Engineering Houston is performing engineering design work.
- Gulf Island Fabrication, Houma, La., a $50 million deck fabrication and integration contract.
- W.H. Linder & Associates, Metairie, La., a contract valued at about $10 million for engineering design of the topsides and procurement support.
These contracts, combined with the costs for Petronius' drilling and production facilities-including compression, process, and injection systems-and living quarters, wells, and pipelines, account for the total project cost of about $400 million.
Project details
Petronius, owned 50-50 by Texaco and Marathon, lies in 1,754 ft of water on Viosca Knoll Block 786 about 130 miles southeast of New Orleans. After appraisal was completed earlier this year, it was declared commercial.
McDermott Engineering Houston is performing the design work, and the company's fabrication yard near Morgan City will construct the tower.
The topsides, consisting of a drilling and production deck and processing facilities, are under construction at Gulf Island Fabrication.
Petronius will be developed with a 21 well slot compliant tower. Total tower weight, including tower sections, foundation template, piles, and conductors, is expected to be about 43,000 tons. The tower will be constructed in two sections, a base and a top. Twelve piles, three at each corner leg, extend from the tower legs through the mudline 450 ft into the seabed to provide the foundation capacity.
The topsides are 210 ft by 140 ft by 60 ft tall and contain all processing equipment, water injection facilities, export pipeline pumps, and utilities. The topsides weigh more than 7,500 tons and will support a full drilling rig.
The installation portion of McDermott's contract will take place in two work seasons for the company's marine operations. The installation of the foundation for the structure will take place this year. The company also will install the topsides along with the tower sections in 1998. Both installation procedures will be handled by McDermott's dynamically positioned derrick barge No. 50.
Construction of the tower and deck is expected to take 18 months.
A 20 mile, 14 in. oil pipeline and a 12 mile, 12 in. gas pipeline will be laid to transport Petronius oil and gas to existing offshore facilities before further transport to shore.
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