Seatrium Ltd. will construct and integrate the hull, topsides and living quarters of the Sparta semi-submersible for Shell’s Sparta development in the Gulf of Mexico (GoM), Seatrium announced Jan. 2.

The contract follows a letter of intent the companies signed on Aug. 28, 2023.

The Sparta semisubmersible production unit will be installed in the Garden Banks area of the GoM in 4,700 ft water depth. This marks the first deepwater development for Shell to produce from the subsalt Paleogene reservoir with pressures up to 20,000 psi. The unit will be designed to produced 90,000 boe/d.

On Dec. 19, Shell announced it was greenlighting its operated Sparta development, where eight oil and gas producing wells are planned initially. The field has an estimated, discovered recoverable resource volume of 244 MMboe and is scheduled to begin production in 2028 as Shell’s 15th deepwater host in the GoM.

Seatrium’s Goliath twin cranes, capable of lifting up to 30,000 tonnes, will integrate and lift the Sparta topsides.

According to Shell, the Sparta FPU host plan follows a development approach based on standardized and simplified host designs.

Previously, Seatrium delivered the Vito and Whale floating production units (FPU) to Shell. Vito, in the greater Mars Corridor, began production in Feb. 2023, while Whale will be located in the Perdido corridor and is scheduled to go onstream in 2024.

In a Dec. 19 press release, Shell called Sparta an “enhanced replication” of Whale, replicating about 95% of Whale’s hull and 85% of Whale’s topsides.

“Shell’s latest deep-water development demonstrates the power of replication,” Zoë Yujnovich, Shell's integrated gas and upstream director, said in a press release.

The Sparta development will be the first of Shell's replicable projects to feature all-electric topside compression equipment, the company said.

Shell operates Sparta, which was originally discovered in 2012 by Cobalt Energy, with 51% interest on behalf of partner Equinor with 49% interest.

A week before announcing final investment decision on Sparta, Shell announced it was moving forward with its Great White development project, which will deliver production from three Great White wells to the Perdido spar in the Alaminos Canyon section of the GoM.