The Mahogany-1 well was discovered on 18th June 2007 in the West Cape Three Point license area of Ghana. The well was drilled with the Belford Dolphin drillship to a total depth of 3683m in a water depth of 1320m.
The Mahogany-1 well targeted the Santonian turbidite stratigraphic trap that opens a new play fairway in the Tano Basin. It encountered a gross hydrocarbon column of 270m with 85m net pay stack.
In August 2007, Tullow Oil Plc using the Beldford Dolphin drillship made a discovery upon drilling the Hyedua-1 well in the Deepwater Tano license area offshore Ghana. It discovered significant light oil. Based on the initial data from the well it was believed then that the Hyedua-1 and Mahogany-1 wells were likely representing a single continuous trap extending across the West Cape Three Points and Deepwater Tano Blocks.
The Hyedua-1 well was drilled as the initial exploration well on the Deepwater Tano license. It targeted the equivalent Santonian turbidite sandstones encountered in the Mahogany-1 Discovery, located approximately 5.3 km to the northeast of Hyedua-1 well.
The Hyedua-1 well encountered a gross reservoir interval of 202m with 108m of high quality stack of reservoir sandstones and a net hydrocarbon-bearing pay of 41m. This well was drilled to a total depth (TD) of 4002m in a water depth of 1530m.
The Ebony-1 well was spudded on 22nd October, 2008 and reached a total depth of 2640m in a water depth of 86m using the West Ceres semi-submersible. The well lies in the South-West part of shallow water Tano block. It encountered a pay of a four meters oil bearing interval at 2053m and a two meter high-pressure gas condensate interval at 2570m.
Odum-1 is the second exploratory well drilled in West Cape three Points license area offshore Ghana. It was drilled to a total depth of 3391m in a water depth of 955m under the operatorship of Kosmos Energy using the Songa Saturn drillship. It encountered a gross oil column of 60m and a net pay of 22m of 29 degrees API oil.
The Tweneboa-1 well was drilled in March 2008, by Tullow Oil Plc using the Eirik Raude semi-submersible rig in the Deepwater Tano block in a water depth of 1148m. The well was drilled to a total depth of 3593m and encountered a 21m net pay. The well was optimally located to penetrate multiple targets, including the edge of an under-drilled major Turonian fan system.
The Dahoma-1 well is 11 km to the south of Mahogany-3 in the West Cape Three points license area. It was to explore the down-dip satellite prospect within the southeast Jubilee area. It encountered a 30m good quality sandstone reservoir below a possible oil-water contact, and some indication of oil migration pointed to a good potential for oil trapped up-dip.
The Atwood Hunter rig was used in the drilling of the Dahoma-1 well to a total depth of 4390 m in a water depth of 1564m. The well was spudded on the 8th of February 2010 under the operatorship of Kosmos Energy, Ghana.
The Owo-1 discovery was made in July 2010 by Tullow oil Plc as it explored in the deepwater Tano license area offshore Ghana. The well is 6km to the west of the Tweneboa-1 well. It encountered a gross vertical reservoir interval of 154m with total net pay of 53m found in two zones of high quality stacked reservoir sandstones. Initial test indicated that these zones were of the same accumulation and samples showed that it was a light oil of between 33 and 36 degrees API.
The Sedco-702 semi-submersible was used in the drilling of the Owo-1 well in a water depth of 1428m to a total depth of 3891m.
The Teak-1 well was drilled under the operatorship of Tullow oil Plc in the West Cape Three Points license area in a water depth of 868m to a total depth of 3170m. It discovered approximately 73m of hydrocarbons in two Campanian and three Turonian-aged reservoir. The well was drilled with the Atwood Hunter semi-submersible rig.
A six (6) metre oil pay was found in the upper zone and 33m of gas pay with an underlying 15m of 40 degrees API oil leg in the lower zone. In the deeper stratigraphic Turonian-aged reservoirs, the well intersected 14m of gas-condensate pay in two separate zones and 5m of 32 degrees API oil pay in a deeper level.
The Mahogany Deep-2 well was drilled about 2 km to the west of the Mahogany-3 appraisal well to appraise the down-dip extent of oil pools found in Mahogany-3. It was drilled by Kosmos on the West Cape Three Points license with the Aban Abraham drillship in a water depth of 1354m and a total depth of 2150m. It was the furthest down-dip appraisal well drilled by Kosmos on the West Cape Three Points license as of that time.
The well encountered a 15 m pay of high quality sandstones which appeared to be in static pressure communication with the reservoir of similar geological age penetrated in the Mahogany appraisal wells. It also intersected 20m of high quality water-bearing reservoir.
Vitol Upstream Ghana, in partnership with GNPC and Eni, operated the Sankofa-1 well in the Offshore Cape Three Points block in a water depth of 866 m. The well was drilled to a total depth of 3702m using the Blackford Dolphin semi-submersible rig. It encountered high-quality reservoir sands containing 36.3 m (net) of oil and gas (33.1 m of gas and a 3.2 metre column of oil). The success of this well confirmed the prospectivity of the Upper Cretaceous reservoir sands in the Tano/Cape Three Points Basin. This discovery was made in September 2009.
In January 2013, Eni SpA successfully drilled the Sankofa East-1 well in the Offshore Cape Three Points block. It was drilled with the Transocean Marianas semi-submersible rig in a water depth of 990 m to a total depth of 4050 m. The well encountered 23m of gas and condensate with a net pay of 17m and a 76m of gross oil pay (32 m net) in the Cretaceous.
The Gye-Nyame-1 well was drilled in the Offshore Cape Three Points block 50km off the coast of Ghana. It was drilled under the Operatorship of Eni Ghana E and P using the Sedco-702 semi-submersible. It is 16 km to the east of the Sankofa discovery. The well was drilled in a 519m water column to a total depth of 3349 m.
The Gye Nyame -1 gas and condensate in a lower Campanian reservoir, where both fluids and reservoir rock were very similar in composition to those at Sankofa. The secondary Albian target for the well was dry and marked by formations of low porosity and permeability. The well also encountered 15m of net sands in the Cenomanian formation, which was mainly water bearing.
The Dzata-1 well was spudded on the 12th of May 2011 under the operatorship of Lukoil in the Cape Three Points water block offshore Ghana. The well was drilled to a total depth of 4500 m from sea level using the Transocean Marianas semi-submersible. It encountered a 94 metre-thick hydrocarbon column containing 25m multilayer of oil and gas pay. The primary reservoir contains light oil and gas.
HESS GHANA DISCOVERIES
Hess Corporation in its exploration campaign has drilled seven exploration wells as at January 2014 in the Deepwater Tano/Cape Three Points block offshore Ghana. The wells are namely Paradise-1, Hickory North-1, Beech-1, Almond-1, Pecan-1, Cob-1 and Pecan North-1.
Below are the details of the various discoveries
|WELL NAME||RIG||WATER DEPTH||TOTAL DEPTH||NET PAY||HYDROCARBON TYPE|
|PARADISE-1||Stena DrillMax||1841m||4737m||126m||Oil & Condensate|
|HICKORY NORTH-1||Stena DrillMax||1968m||5736m||30m||Gas Condensate|
|PECAN NORTH-1||Stena DrillMax||2260m||4518m||12m||Oil|