INPEX taps Aquaterra for subsea structural support in Indonesian deepwater project

September 16, 2025, by Dragana Nikše

INPEX Masela, a joint venture between INPEX and the Japan Organization for Metals and Energy Security (JOGMEC), has tasked Aquaterra Energy, a UK-headquartered offshore energy engineering solutions provider, with carrying out structural analyses for its operations off the coast of Indonesia.

Thanks to the deal, Aquaterra Energy will support upcoming subsea drilling campaigns offshore Indonesia by delivering multi-phase conductor and riser analysis for deepwater wells in water depths ranging from 600 to 800 meters.

The scopes of work, which will be delivered in stages over the next six months, include structural analysis and the definition of operating envelopes, technical limits covering weather conditions, rig movement, and fatigue.

Martin Harrop, Offshore Analysis Manager at Aquaterra Energy, noted: “Being brought in at this early stage of the projects allows us to provide maximum value analysis and insight that support informed, high-quality project planning. Our work is helping INPEX define key operating parameters early, so that procurement and design decisions can be made with greater confidence, efficiency and accuracy. We’re helping to set the technical direction now, which will enable a well-structured and robust campaign later.”

Aquaterra believes its early involvement will help INPEX define safe operating limits, giving it greater confidence in the technical aspect of pre-drilling plans. The inputs received will play a part in matters such as rig selection and equipment specification.

The contract win follows an extension the U.K. firm recently secured off Egypt. Under the initial contract from 2023, the company delivered riser and subsea well/conductor analysis for operations at seven well locations. Now, the extended scope entails continued analysis of producing subsea wells drilled from a semi-submersible rig.

The INPEX Masela JV was formed in 1998, when it acquired a 100% interest in the Masela block. The Abadi gas field was discovered two years later. The JV now operates the Abadi LNG project with a 65% stake, with partners Pertamina (20%) and Petronas (15%) coming on board in 2023 after Shell decided to divest its stake in the project.

Said to be one of the largest projects in Asia, Abadi LNG is expected to produce approximately 9.5 million tons per annum (mtpa) of LNG by liquefying natural gas from the Abadi gas field at an onshore facility.

A consortium comprising JGC Indonesia and Indonesian affiliates of Technip Energies recently won a front-end engineering and design (FEED) contract for work relating to the project’s floating production, storage, and offloading (FPSO) facility and an onshore liquefied natural gas (OLNG) plant.