Chevron has, as expected, gone with Intecsea to carry out the engineering and long-lead procurement services for the Front End Engineering and Design (FEED) phase of the deepwater Buckskin-Moccasin development in the US Gulf of Mexico.

An integrated WorleyParsons-Intecsea team only just recently completed the pre-FEED work for the development, which will now see the fields developed via a subsea tieback to an unspecified “nearby production facility”. It is likely that this will be the producing Jack-St.Malo production platform located some 50 km away, and operated by Chevron. That platform came onstream in December and is expected to eventually produce up to 94,000 b/d of oil and 21 MMcf/d of gas.

Intecsea will execute the FEED and procurement services for the subsea tieback from the fields to the production facility, with the company’s offices in Houston to execute the project, with support from its office in Hyderabad, India.

The plans have changed dramatically over time on Buckskin-Moccasin, which was previously studied for development via a proposed standalone semisubmersible production facility. In 2013 WorleyParsons-Intecsea was selected by Chevron to carry out engineering services for such a facility on the fields, both located in the Lower Tertiary trend. The company executed a pre-FEED preliminary design phase for the deepwater subsea architecture, riser interface and topside facility design for the semisubmersible.

Relatively disappointing appraisal programmes on both fields (in particular on Moccasin, DI understands) compared to initial expectations, plus the general rise in development costs and fall in the oil price over the past year or so, saw Chevron continually scale back its initial standalone scheme, considering various scaled-down options throughout the process including at one point a ‘Jack-St.Malo 2’ duplicate, DI hears.

Buckskin sits in 2,127 m (6,978 ft) of water in Keathley Canyon Blocks 785 and 872 and is owned by Chevron (operator, 55%), Maersk Oil (20%), Repsol E&P USA Inc. (12.5%) and Samson Offshore LLC (12.5%). It was discovered in 2008. Nearby Moccasin is owned by Chevron (operator, 43.75%), BP (43.75%) and Samson (12. 5%), and is located in KC 736.

Interestingly, not too far away from Buckskin is partner Repsol’s recent and substantial ultra-deepwater Leon oil discovery in KC 642 some 50 km northwest, which could therefore end up being part of the plan. Repsol is the operator of the consortium with 60%, with Colombia’s Ecopetrol holding the remainder, with the Spanish operator having strong ambitions for the GoM which could well see it consider its own hub facility in the area. The Leon well hit more than 150 m (492 ft) of net oil pay within a column of more than 400 m (1,312 ft), and was drilled in a water depth of 1,865 m (6,119 ft).