Afren opens new fairway in East Africa

Afren has completed the acquisition of Black Marlin Energy Holdings.

Offshore staff

LONDON -- Afren has completed the acquisition of Black Marlin Energy Holdings.

Black Marlin holds licenses throughout East Africa in basins with proven working hydrocarbon systems, and with the potential for large oil discoveries. Afren estimates its net prospective resources at 1.2 Bbbl.

The company has drawn up a multi-well exploration campaign across its new assets through to end 2012, and will in parallel continue studies into further prospectivity. The acquisition package also brings ownership of one of the largest East African seismic databases.

Among the assets are two exploration blocks offshore southern Kenya in the Lamu coastal basin. Blocks L17 and L18 cover respectively 1,275 and 3,630 sq km (492 and 1,401 sq mi), in water depths varying from a few meters along the shoreline to around 500 m (1,640 ft).

Prospective source rocks have been identified in the Cretaceous within the Southern Lamu basin, including the Permo-Triassic Karoo interval and sections within the Lower to Middle Jurassic. Additionally, oil seeps have been recorded in the Lamu basin and Pemba Island that have been geochemically linked to a Jurassic source, which suggests that the structures in block L17/L18 are most likely oil bearing.

The main reservoir targets are in the Upper Cretaceous, with possible further potential in Tertiary sequence clastic reservoirs. Both the offshore blocks are close to Mombasa and its large population, so any commercial discoveries theoretically could be quickly monetized.

The PSC partners have fulfilled their commitments to acquire 25 geochemical cores and 1,000 km (621 mi) of marine 2D seismic. During the second exploration period, they are obliged to acquire a further 1,000 km (621 mi) of seismic and to drill one exploration well, followed in the third period by 1,250 km (777 mi) of seismic and two more exploration wells.

Black Marlin also brings license interests offshore the Seychelles, covering a total area of roughly 14,964 sq km (5,777 sq mi). Areas A and B are mainly in shallow water in the northern half of the Seychelles plateau, while Area C is in shallow water to the south. Afren operates the blocks with a 75%, in partnership with Avana Petroleum.

Exploration around the Seychelles started in 1977 when three separate PSCs were signed by a consortium led by Oxoco, Siebens, and Burmah Oil (later acquired by Amoco). During 1980-81, Amoco drilled three wells (Owen Bank A-1, Reith Bank-1, and Seagull Shoals-1), all of which were plugged and abandoned with hydrocarbons shows.

Later, Amoco commissioned a 27,900-km (17,336-mi) aeromagnetic survey and 7,100 km (4,412 mi) of seismic, plus various gravity and geochemical surveys, before relinquishing the acreage in 1986.
Also in the 1980s, Enterprise Oil signed an agreement for the southeastern shelf plus Constant, Coetivy, and Fortune Banks Platte banks. It acquired 4,870 km (3,026 mi) of seismic and in 1990 it drilled the Constant Bank-1 well which was plugged and abandoned. In 1991, a consortium of Texaco, Ultramar (now ENI) and Enterprise Oil also acquired seismic.

EAX (Black Marline) and Avana were awarded a PSC for areas A, B, and C in November 2008. It has an initial exploration period of two years, followed by two additional exploration periods (the first lasting two years and the second lasting three years) before entering an exploitation phase lasting up to 25 years.

The partners acquired 3,637km (2,260 mi) of 2D seismic data in 2007 and a further 1,271 km (790 mi) last year. During the second exploration period, they must acquire a further 1,500 km (932 mi) of 2D seismic and drill one exploration well, followed by 1,000 km (621 mi) of 2D seismic and two more wells in the third period.


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