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Shell and Nexen in design phase for Gulf of Mexico Appomattox platform

Shell and Nexen to take experience from Olympus

In order to develop the challenging Appomattox oil field in the US Gulf of Mexico, the Royal Dutch Shell (Shell) and its partner Nexen, a wholly owned subsidiary of the China National Offshore Oil Corporation (CNOOC), intends to take the lessons learnt from the Olympus Tension Leg Platform (TLP) to design and execute on fast track the large Appomattox semi-submersible offshore platform at minimum risks.

Located approximately 115 kilometers offshore the Louisiana Gulf Coast, the Appomattox oil field is lying by more than 2,200 meters of deep water depth in the Block 392 of the Mississippi Canyon in the Gulf of Mexico.

Shell_Nexen_Appomattox_Semisubmersible_Platform_MapOnly five miles away from the Appomattox field, Shell and Nexen made major discoveries in the Vicksburg oil field trapped in a Jurassic reservoir by 2,500 meters of water depth and 8,750 meters of total depth.

Shell and Nexen acquired the license in 2002 and made the first oil discovery in Appomattox in 2009, but because of the ultra deep water of the field, the high pressure and high temperature of the oil and gas in the reservoir, Shell and Nexen wanted to proceed step by step in their strategy to develop Appomattox and Vicksburg projects.

In Appomattox, Shell owns 80% interest leaving 20% to Nexen and in Vicksburg, Shell is still the operator with 75% share and Nexen 25%.

In addition to Appomattox and Vicksburg, Shell and Nexen carried out an additional test well in Corinth, right in between the both fields, but did not report findings yet.

Shell Appomattox semisub platform at design phase

For now, Shell and Nexen estimated the recoverable reserves in Appomattox at 500 million barrels  of oil equivalent (boe) while Vicksburg is granted of about the same amount.

In this context, Shell and Nexen are intending to tie Vicksburg in the Appomattox semi-submersible platform with the option to convert Appomattox into local production hub depending on the amount of the future discoveries in the neighboring blocks.

Shell_Nexen_Appomattox_Semisubmersible_PlatformIn these conditions, the Appomattox semi-submersible platform should have a treatment capacity of 100,000 barrels per day (b/d) of crude oil.  

Willing to benefit from the successful experience in Olympus, Shell and Nexen, develop Appomattox with similar process and selected Houston Offshore Engineering to design the topsides.

If Shell and Nexen continue in the same logic to benchmark Olympus, Samsung Heavy Industries should be involved for the execution of the 50,000 tonnes Appomattox hull and Kiewit Offshore for thetopsides of the semi-submersible platform.

According to the current progress of the project, Shell and Nexen, from CNOOC, are planning to award the engineering, procurement and construction (EPC) contracts for the Appomattox semi-submersible platform in 2014 in expecting the first production by 2017.

For more information and data about oil and gas and petrochemical projects go to Project Smart Explorer

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