Rosmari-Marjoram is a deep-water sour gas project being developed off the coast of Sarawak, Malaysia.

Shell-subsidiary Sarawak Shell Berhad (SSB) operates the gas field with 80% interest. Carigali Sdn Berhad, a subsidiary of Petronas, holds the remaining 20% stake in the project.

The project comprises Rosmari and Marjoram fields, which were discovered in 2014.

The partners took the final investment decision (FID) to develop the Rosmari-Marjoram gas project in September 2022.

It will be designed to produce 800 million standard cubic feet of gas per day (MMscf/d), with production slated to begin in 2026.

The offshore development will also help in ensuring a sustained gas supply for the Petronas LNG Complex in Bintulu, Sarawak.

Location details

Rosmari-Marjoram Sour Gas Fields are located 220km off the coast of Bintulu, Sarawak in Malaysia.

The project is being developed as part of the Block SK318 exploration and production sharing contract. The water depth in the region is around 2,624ft.


Shell discovered the Rosmari-Marjoram gasfield in 2014. The successful ‘Rosmari-1’ well encountered more than 450m of gas column in April 2014.

The exploration well, located 135km offshore in Block SK318, was drilled to a total depth of 2,123m.

Shell achieved further success in Block SK318 after Marjoram-1 well made another gas discovery in August 2014.

The Marjoram-1 well is located in 800m of water around 180km off the coast of Malaysia.

Project details

The Rosmari-Marjoram Sour Gas Project will include a remotely operated offshore platform, ancillary infrastructure and an onshore gas plant.

The offshore platform will feature a topside, a four-legged jacket and piles.

The platform will be installed at a water depth of 140m within SK318 area, off the coast of Bintulu, Sarawak.

The offshore platform will supply gas to the onshore plant via one of the longest sour wet gas pipelines located offshore in the world extending nearly 207km.

The overall Rosmari-Marjoram project will source power primarily from renewable sources.

The offshore platform will be powered by 240 solar panels, while the onshore gas plant will be connected to the Sarawak Grid System which is fed by hydroelectric power.

For back-up, diesel generators and batteries will be used.

According to Shell, Rosmari-Marjoram Onshore Gas Plant will be SSB’s largest onshore project in Sarawak since Bintulu Crude Oil Terminal (BCOT) and Bintulu Integrated Facility (BIF) which were constructed in the late 1970s.

Contractors involved

In May 2020, Worley’s Malaysian subsidiary Perunding Ranhill Worley (PRW) secured the Front-End Engineering Design (FEED) contract for the offshore scope of work of the Rosmari Marjoram project.

In October 2022, the engineering, procurement, and construction (EPC) contract for the solar powered offshore platform was awarded to Malaysia Marine and Heavy Engineering (MMHE), a wholly owned subsidiary of Malaysia Marine and Heavy Engineering Holdings Berhad (MHB).

With a design life of 20 years, the Rosmari-Marjoram Gas Project’s offshore platform will have the capacity to cater for up to 800 million standard cubic feet of gas per day. The platform will supply natural gas to the Petronas LNG Complex in Bintulu, Sarawak.

Samsung Engineering won an engineering, procurement, construction, and commissioning (EPCC) contract for the Rosmari-Marjoram Project’s onshore gas plant. The $680m contract was awarded in September 2022.

Earlier, South Korean companies Samsung Engineering and Hyundai Engineering & Construction secured parallel FEED contracts for the onshore gas plant.

Shell’s upstream activities in Malaysia

Shell has been present in Malaysia for more than 100 years. In 2020, the company completed 110 years of upstream operations in the country.

Shell’s upstream activity focuses on extracting crude oil and natural gas from offshore Sarawak and Sabah.

The company’s subsidiary SSB signed exploration and production sharing contract for SK319, deep-water blocks 2B and SK318, offshore Sarawak, in 2012.

Gumusut-Kakap field in Sabah, a deep-water project in Malaysia, began production in 2012, while the FID on Malikai offshore Sabah was taken in 2013.

In 2014, SSB took FID on E6 field development offshore Sarawak.