Project Profile
Location: Mississippi Canyon Blocks 503 and 547
Life of the field: 30 years
Reserves: Between 100 and 300 million barrels of oil equivalent
Water Depth: 945 metres
Exploration start-up: December 2007
Production start-up Year: - December 2011
The Who Dat oil and gas field is located in the Mississippi Canyon (MC) blocks 503/504/547 of the Gulf of Mexico (GOM), in a water depth of 945m. The estimated life of the field is 30 years. LLOG Exploration is the operator of the field with a 67.5% working interest. First production from the field was achieved in December 2011. Who Dat is estimated to contain between 100 and 300 million barrels of oil equivalent, of which 70% is oil. The oil and gas reserves have low amounts of wax and no asphaltene flocculation.
The Who Dat field was discovered in December 2007 by the OCS-G 27277 Well A1 in the MC block 504. The well was drilled by Diamond Offshore\'s Ocean Victory semisubmersible drilling rig. Two more wells were drilled in 2010 to further appraise the field by the Noble Lorris Bouzigard and Noble Amos Runner semisubmersible rigs. The additional wells expanded the field into blocks 503 and 547. The Who Dat field is made up of ten stacked reservoirs of the Pliocene and Upper Miocene age. The reservoirs are located at a depth of 10,000ft-17,000ft, with pressures ranging between 6,000psi and 12,500psi. The three wells drilled at the field have encountered more than 700ft of net pay in the reservoirs. The wells flowed at the rate of 10,000 barrels a day of oil and 60 million cubic feet a day of non-associated gas.
The field was developed using a semi-submersible Opti-Ex floating production system (FPS). The existing wells were completed and additional wells were also drilled. These wells are connected to a subsea system capable of handling up to 12 wells. Flexible risers connect the wells to the Opti-Ex FPS. The OPTI-EX FPS was acquired by LLOG for operations at the field. It has a production capacity of 60,000 barrels of oil a day (bopd), 150 million standard cubic feet of gas a day (mmscfd) and 40,000 barrels of water a day (bwpd). The facility was installed at the field in July 2011. It has been specifically designed for operation in the GOM at a cost of $400m. The FPS is designed to withstand a 1,000-year storm. The OPTI-EX FPS is held onto the seafloor by 12 mooring lines connected to 80ft suction pile anchors. The hull of the FPS is a deep draft ring-pontoon. The FPS is designed in such a way that it can be modified quickly and used at other fields at the end of its operations there.
The subsea system for the field includes ten miles of 6in flowlines, six risers, nine jumpers and jumper tie-ins, three manifolds and other equipment. Oil produced at the field is transported through a 19-mile long, 14in diameter export oil pipeline, which connects to the Mars pipeline system. The pipeline carries the oil to Shell production facilities onshore where it is processed. The gas is exported through a 17-mile long, 10in diameter gas pipeline, which connects with the Independence Trail pipeline operated by Enterprise Field Services.
Operator:
LLOG Exploration Company, L.L.C.: Operator with 67.5% interest
Contractors:
Expro: Subsea services contract
FMC Technologies: Design, manufacture and supply of subsea production systems
Sevan Drilling: Drilling using the Sevan Louisiana ultra-deepwater drilling rig