The Yellowtail project involves the development of Yellowtail and Redtail fields in the Stabroek Block, offshore Guyana. Image courtesy of Jon Olav Eikenes/Flickr.
The Yellowtail subsea wells will be tied back to a floating production, storage and offloading (FPSO) vessel. Image courtesy of kamingusu/Flickr.
The Yellowtail-1 discovery well was drilled by the Noble Tom Madden drillship in 2019. Image courtesy of -EZEK/Flickr.

Yellowtail Development is the fourth project planned in the deepwater Stabroek Block offshore Guyana.

The project involves the development of the Yellowtail and the Redtail discoveries located in the eastern half of the Stabroek Block. It will be a subsea development tied back to a new floating production, storage and offloading (FPSO) vessel.

Esso Exploration and Production Guyana (EEPGL), a subsidiary of Exxon Mobil, is the operator and holds 45% interest in the Stabroek Block, while Hess Guyana Exploration and CNOOC Petroleum Guyana hold 30% and 25% interest, respectively.

The project partners submitted an environmental impact assessment (EIA) report of the project to Guyana’s Environmental Protection Agency (EPA) in October 2021 and awarded the contract for front-end engineering and design (FEED) of the FPSO in November 2021.

Subject to approvals from the Guyanese authorities and final investment decision (FID) by the project partners, the Yellowtail offshore development is expected to start production between 2025 and 2026 and continue to be operational for at least 20 years.

Yellowtail development project location and discovery details

The Yellowtail Development will be located 203km north-east off the coast of Georgetown, Guyana. The water depth in the project area ranges from 1,700m to 1,900m.

The Yellowtail field was discovered by drilling the Yellowtail-1 exploration well in April 2019. It was Exxon Mobil’s 13th discovery in the Stabroek Block.

Drilled by the Noble Tom Madden drillship to a depth of 5,622m, the Yellowtail-1 well encountered 89m of oil-bearing sandstone reservoir in the Turbot area of the Stabroek Block.

Yellowtail-1 was followed by the Yellowtail-2 exploration well and the Redtail discovery through the Redtail-1 exploration well in 2020. The Yellowtail-2 exploration well encountered 21m of net pay in newly identified oil-bearing reservoirs among the original Yellowtail-1 intervals.

The Redtail-1 well, located 2.5km north-west of the Yellowtail discovery, encountered 70m of high-quality oil-bearing sandstone reservoir in September 2020.

Yellowtail project development plan

The Yellowtail development project will be a subsea development with up to 67 wells, including production, water injection and gas re-injection wells, drilled from six drill centres.

The subsea system will include 51 enhanced vertical deepwater trees (EVDTs) and 12 manifolds along with associated controls and tie-in equipment.

The subsea production, water injection and gas re-injection facilities will be clustered around drill centres requiring fewer manifolds, flowlines, and umbilicals.

Yellowtail FPSO details

The Yellowtail FPSO is planned to be spread moored in a water depth of approximately 1,800m. The FPSO topsides will feature process modules to separate oil, gas and water from the well stream, along with utility modules and living quarters for up to 160 personnel.

The FPSO unit will have a crude oil processing capacity of 250,000 barrels a day (bpd), associated gas treatment capacity of 450 million cubic feet a day (Mcfd), water injection capacity of 300,000bpd and crude oil storage capacity of two million barrels.

While shuttle tankers will transport stabilised oil from the FPSO to the shore, a portion of the associated natural gas will be utilised for power generation on the FPSO and the remaining injected into the field reservoirs.

Contractors involved in the Yellowtail development project

TechnipFMC received a contract valued between £372.6m ($500m) and £745.2m ($1bn) from EEPGL to deliver the overall subsea production system for the Yellowtail development in November 2021.

TechnipFMC will be responsible for project management, engineering, manufacturing and testing of the entire subsea production system.

SBM Offshore was awarded the FEED contract for the FPSO of the Yellowtail Development project in November 2021.

SBM Offshore also previously designed and constructed the Liza Destiny, Liza Unity and Prosperity FPSOs for operation within the Stabroek Block.

Stabroek Block details

The Stabroek Block lies approximately 190km off the coast of Georgetown and is spread over 6.6 million acres (26,800km2) of the Atlantic Ocean offshore Guyana, where the water depth ranges between 1,500m and 1,900m. The giant offshore block was estimated to contain up to ten billion barrels of oil equivalent (bboe) in recoverable resources as of October 2021.

The Stabroek Block partners have already sanctioned three development projects, namely Liza phase one, Liza phase two and Payara, all located in the eastern half of the block.

Liza phase one commenced production in December 2019, while Liza phase two and Payara are expected to come on stream in 2022 and 2024, respectively.

The Yellowtail and Redtail discoveries being developed as part of the Yellowtail project are located approximately 30km south-east of the Liza developments.

Other major discoveries in the Stabroek Block include Snoek, Turbot, Ranger, Pacora, Longtail, Hammerhead, Pluma, Tilapia, Haimara, Tripletail and Pinktail.