- Nomeco's Yombo Field off Congo
- Marathon's Tchatamba Marine Field off Gabon
- Shell's Bonga Field off Nigeria
Exxon has plans for carpet 3D. The water depths range from 200-2000 meters. Occidental is scouting for a 50% farm-in partner for their Marine XI and XII in offshore Congo. Elf has concluded a 750 sq km 3D survey in Marine X and is about to acquire 885 sq km 3D and a 1,000 km 2D seismic in very deepwater.
Equatorial Guinea to double Zafiro outputMobil's proposed upgrade of the Zafiro Producer, an FPSO facility, is to double the production from Zafiro and satellite fields in water depths of 200 meters offshore Equatorial Guinea, according to sources at Mobil's head office. Zafiro is currently delivering 40,000 b/d oil. In early February, Mobil Equatorial Guinea let a contract valued in excess of $115 million to Oceaneering International Houston for modifications to the facility, as part of phase two Zafiro Field development. The production will be increased to 80,000 b/d by the end of the year.
Meanwhile, the Mobil/UMC joint venture announced, in early March, the successful completion of the Jade #2 well, which confirms the Jade Field discovery on Block B offshore Equatorial Guinea. The Jade #2 well was drilled about two-thirds of a mile north of the Jade-1, and it flowed 5,465 b/d oil from the Jade sands in the Lower Qua Iboe formation.
The Jade Field, stratigraphically shallower than the main pay sands in the Zafiro Field, was discovered last December by the Jade #1 well, which tested at a rate of 2,000 b/d oil. Jade #2 confirms that the seismic data can clearly delineate oil-bearing reservoirs. Development of the field will be through flowlines from subsea wells tied back to the Zafiro Producer, the floating production, storage and offloading vessel (FPSO), which has been on production in the Zafiro Field since August 1996. Initial production from the Jade Field is planned by yearend.
In the nearby Zafiro Field, the Zafiro #5 development well has come on stream producing at 12,000 b/d. The well was horizontally drilled in the Zafiro sand allowing for the high production rate. Nine other oil wells, including the two Jade wells, have been drilled in the area but are not yet on production. The field is currently producing about 40,000 b/d from seven subsea wells. Capacity is expected to reach 80,000 b/d in the fourth quarter of 1997. Mobil and UMC hold Block B in a 75: 25 division.
Gabon's activity growing rapidly with new drillingAmoco's long awaited Walt Whitman-1, in Phenix Marine, named for a famous American poet, turned out to be a disappointingly dry hole. The original trajectory was abandoned at a shallow depth of 1,572 ft as a result of technical problems. At 8399 feet, the sidetrack, Walt Whitman R, got fairly close to the proposed TD of 9843 feet. It also adequately tested the objective horizon--the pre-salt Aptian Gamba and Dentale reservoirs and came up water-wet. Fortunately, Amoco did not carry the cost of the well alone. An independent E&P company, Forceenergy, has farmed in for 15% of the Block.
Arco's Production Sharing Contract for the Otiti block, in deepwater offshore northwest Gabon, which was signed in August 1995, is Arco's first upstream venture in Gabon. The company has acquired 1500 km of 2D seismic in this area and proposes a 300 sq km of 3D seismic data to cover both the Tolo and Otiti blocks. Arco might be drilling a well in this tract later in the year.
Marathon may be producing the Tchatamba Marine-1 afterall. The company has submitted applications for production of this hugely successful well, which flowed 4,545 b/d oil of 46 degree API oil column from a 74 feet interval of Albian Upper Madiela. Wells 2 & 3 on this structure were dry, forcing Marathon to seriously consider discarding this portion of the Kowe Tract, located in 115 feet water depth offshore Gabon. Two months ago, Marathon was reviewing all the technical data to evaluate the exploration strategy in order to determine whether to continue appraising the structure. But as the company is about to enter its second exploration period on the lease for two years, it seems it has decided to produce , at least from the first well.
Occidental is still offering 50% interest over three tracts in offshore Coastal Basin. They are M'Polo, Chaillu, and Meboun tracts. Two deepwater wildcats were drilled in two blocks. Due to absence of reservoirs, Chaillu Hirondelle Marine 1 was abandoned dry at 10528 feet TD. So was Meboun Cormoran Marine 1 at 10866 feet. Earlier in 1997, Mpolo Falcon Marine 1 failed to find hydrocarbon in the objective Albian Madiela carbonates.
Shell leading Nigerian deepwater thrustShell has emerged the local champion in the deepwater subsector of the Nigerian oil industry. In late February, the company suspended Ngolo-1 in OPL 219, with a significant oil find. This means that Shell has found significant oil in two wells out of two, a spectacular result for Niger Delta deep offshore, where eight of the 10 wells spudded so far have been abandoned. Shell is currently on Bonga- 2 appraising what might become the biggest deepwater discovery in the Gulf of Guinea. Bonga-1 discovered 400 ft Net Oil Sand in four pay zones and flowed enough during DST tests to warrant speculations that the discovery well alone can produce 15,000 b/d oil for ten years. Bonga is estimated at holding 400 million bbl oil estimated recoverable. Shell is going to drill Bonga-2, 3, & 4 back to back throughout 1997.
Conoco is going ahead to produce the Ukpokiti Field (OML 108) from May 1997. The field is a funnel shaped structure located downdip (seaward) of Chevron's huge Meren Field. The discovery well, Ukpokiti-1 flowed a cummulative 10,000 b/d oil in two sands.
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