Thunder Hawk lies in Mississippi Canyon block 734 in the Gulf of Mexico 150 miles south-east of New Orleans, in water depths of 1,745m (5,724ft). Murphy holds a 37.5% working interest, with Dominion and Hydro Gulf of Mexico each holds a 25% share. Marubeni holds a 12.5% interest.
Thunder Hawk, along with Thunder Bird and Thunder Ridge lie close to the BP-operated Thunder Horse field, the Gulf of Mexico’s largest ever oil discovery. Thunder Hawk, Thunder Bird and Thunder Ridge are on the edge of the Boarshead Basin, a highly prospective region of the Central Gulf.
THUNDER HAWK DISCOVERY
The field was discovered in May 2004 with the exploratory well sidetrack (734 #1 ST1) in a water depth of 5,724ft. This encountered approximately 300ft of net oil pay in two high-quality reservoir zones. The main pre-drill targets were found water-bearing in the original hole (Mississippi Canyon 734 #1). The discovery well was drilled to a depth of 26,520ft TMD and (25,885ft TVD). The sidetrack well was drilled to 24,831ft TMD (23,101ft TVD) subsea and plugged.
A second well was drilled in 5,716ft of water by the Transocean Marianas. It reached 23,765ft TMD when drilling had to be temporarily halted because of severe loop currents, but eventually continued to 28,216ft TMD. The well encountered over 500ft true vertical thickness of pay in two high-quality sands. Estimated reserves have been put at 50 to 80 million barrels.
The Thunder Hawk discovery is being developed using a semisubmersible production unit based on Atlantia’s DeepDraft Semi design. It will have production facilities capable of producing up to 60,000bpd and 70mmcf/d of gas. The unit will have the capacity for further expansion in order to accommodate additional production from satellite discoveries or third party tiebacks.
The produced oil and gas will be exported via Steel Catenary Risers (SCR) into existing pipelines. One candidate could be Thunder Ridge, located just six miles east of Thunder Hawk.
Atlantia will supply the DeepDraft Semi in time for a planned installation scheduled for late 2008 and first oil in 2009. The company awarded Aker Kværner a contract to install the Thunder Hawk semisubmersible. The spread mooring system will be supplied by Aker Kværner subsidiary Aker Marine Contractors , which will also transport and hook up the FPU. The marine installation will use the offshore construction vessel, BOA Sub C.
Noble Denton Marine Services Inc. have been awarded the marine warranty for the Thunder Hawk Field Development Project, by SBM Atlantia. NDMSI scope of work will include the review and attendance for the hull and deck loadout, transport, offload, deck integration lift, tow to site and installation, plus hook-up of pre-installed SCRs.
Fabrication of the hull began at the Dyna-Mac yard in Singapore with topsides being built by Kiewit Offshore Services in Ingleside, Texas, where the two pieces will be mated upon completion.
Intec won the contract for detailed design of flowlines and export pipelines including the detailed design for twin 8in insulated flowlines to be installed in 5,710ft of water.
The lines will transport production fluid from the Thunder Hawk subsea development to the host facility.
Intec also carried out the detailed design work for two 12in export pipelines that will transport the separated oil and gas from the host facility to the Mardi Gras transportation system. These will be installed by Helix Energy Solutions using the 480ft-long S-lay pipeline installation vessel Caesar.
The Thunder Ridge exploratory well Mississippi Canyon Block 737 was drilled (and sidetracked) in over 6,100 feet of water. The primary objective encountered wet sands while the secondary objective discovered a small oil accumulation.
Predrill reserve estimates were put at 100- to 200-million barrels of oil equivalent,
The discovery is located about 15 miles west of Thunder Hawk. Thunder Bird discovery is likely to be developed, with production tied back via a subsea pipeline to the Dominion-operated Devil’s Tower platform on Mississippi Canyon Block 773. Predrill reserve estimates for Thunder Bird range from 50 to 75 million barrels of oil equivalent.