Agogo Oil Field Development, Angola

Agogo oil field is being developed in a water depth of approximately 1,700m in Block 15 / 06, offshore Angola.

Eni Angola is the operator of the oil field with a 36.84% working interest in a joint venture (JV) that was formed to develop the project. The company’s partners in the Block 15 / 06 JV are Sonangol P&P (36.84%) and SSI Fifteen (26.31%).

The field started oil production in January 2020, nine months after its discovery in March 2019. Initial production stood at approximately 10,000 barrels of oil per day (bopd) and is expected to increase to 20,000bopd in the near future. The JV partners are studying the field to tap its complete potential by pursuing full field development through the addition of a new production hub. The final investment decision (FID) on full development is anticipated to take place in 2021.

Agogo oil field discovery

The Agogo oil field was discovered by drilling the Agogo-1 new field wildcat (NFW) well, 20km west to the N’Goma floating production storage offloading (FPSO) located in West Hub production area in Block 15 / 06 and approximately 180km offshore Angola.

The well was drilled to a total vertical depth of 4,450m in a water depth of 1,636m using the Poseidon drillship. The well encountered a single oil column of approximately 203m with net pay of 120m of high-quality oil with 31° API.

The hydrocarbons are present in subsalt diapirs in Lower Miocene sandstones. The prospect was originally expected to hold about 450 to 650 million barrels of light oil in place.

The mapping and drilling of the prospect were performed using Eni’s proprietary imaging technologies. Seismic imaging facilitated high-resolution, three-dimensional imaging of the field. Eni also used the sub-sea multiphase boosting system (SMBS) and gravity gradiometry technology that helps in understanding the nature of the rocks in the area.

Appraisal details of Agogo oil field

The first appraisal well Agogo-2 was drilled approximately 3km north-west to the Agogo-1 discovery well in the Agogo discovery in July 2019. The well results confirmed the presence of 650 million barrels of oil in the field.

The appraisal well was located about 23km from the N’Goma FPSO vessel. The well was drilled in a water depth of 1,700m to a total vertical depth of 3,949m to encounter 58m net pay of light oil with 31° API in the Miocene and Oligocene era sandstones.

The highly deviated Agogo-2 appraisal well confirmed the presence of hydrocarbons to the north of the discovery well and below salt diapirs. The well indicated the production capacity of more than 15,000bopd. A second appraisal well, Agogo-3, was drilled approximately 1.5km north-west of the Agogo-2 well, using the Libongos drillship.Agogo-3 was drilled to a total vertical depth of 4321m in the sandstones of Miocene and Oligocene age. It hit net pay of up to 120m of light oil with 31° API in February 2020. It was drilled as a highly deviated well that reached below the thick layer of salt and confirmed the interconnection of the reservoir in the subsalt area of Agogo megastructure. The well results indicated that the field has estimated oil in place of one billion barrels. New appraisal wells are expected to be considered to evaluate additional upside in the northern sector of the field.

Details of Agogo oil field

Agogo oil field was connected to the N’Goma FPSO to begin production from the field. The FPSO features oil processing capacity of 100,000bopd, gas handling capacity of 115 million standard cubic feet (Mmscf) per day and water injection capacity of 120,000 barrels per day (bpd).

The existing infrastructure facilities were utilised for the development of satellite sub-sea fields.

Contractors involved

Saipem received a contract for the early phase one development of Agogo oil field, in February 2020. The contract requires the company to perform design, engineering, procurement, construction and installation of risers, production flow-lines, and jumpers. The company will also install a sub-sea production system in water depths of 400m to 600m using its fluid delivery solution (FDS) and Saipem 3000 vessels.