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TANZANIA: Tullow Spuds Likonde-1 In The Rivuma

Tullow, the U.K listed, Africa focused operator, has spudded Likonde-1, a newfield wildcat well in its Ruvuma PSA in Tanzania. The well is expected to be drilled to a programmed total depth of 3,200 meters. Drilling time is estimated to be around two months, subject to any operational delays which can occur in a remote frontier area.

Aminex claims that the “Likonde prospect is a robust faulted rollover structure with the potential for 500 million barrels of oil in place and estimated P10 recoverable reserves in excess of 150 million barrels of oil”, risked by Aminex “at a 1 in 4 chance of success”. The Likonde-1 well will test multiple targets in the Tertiary, Cretaceous, and Permo-Trias Karoo intervals.

Pursuant to a recent farm-out, finalization which was announced on 15 December, interests in Likonde-1 are Tullow Oil (operator) 50%, Aminex 37.5% and Solo Oil PLC 12.5%.

Afren’s Ebok… Six Horizontal Wells Will Start the Drainage

Afren’s first phase development plan for Ebok field comprises five horizontal oil production wells in the D2 reservoir, one horizontal oil production well targeting the Dl reservoir and one water injection well in the central Fault Block 1 and Fault Block 2 areas of the field. All wells will be drilled from a single field location via a Well-head Support Structure (“WSS”) and mobile offshore production unit (“MOPU”). Fabrication of the WSS is complete and is in transit for delivery to the project. The company is in the process of finalising contract discussions on the production facilities. Associated gas produced will be utilised as fuel for the facilities’ power generation and as gas lift to assist well productivity.

Following completion of the initial development phase, the subsequent development phases will incorporate the full development of the D2 Southern Lobe, Dl reservoir (Fault Block 1 & 2 areas), and Fault Block West, whilst appraising the potential within the West Flank Qua Iboe structure, the 1)2 Upside Extension and the Fault Block North (cumulative total of 212 MMBBLS STOOIP and 66 MMBBLS recoverable), Afren’s report states.

NIGERIA; Afren Claims Substantial Reserves Increase in Ebok

‘Volumes Jump From 25 Million (predrill) To 116 Million Barrels After The Wells

Afren has reported a total gross hydrocarbon column of 107 ft in the appraisal well Ebok- 6 in the prolific south east shallow offshore Niger Delta. The company didn’t exactly report the net pay, but says that “greater than expected hydrocarbon column has led to an upgrade in D2SL volumetrics post Ebok-6”.

The new finds in three appraisal wells have shot up estimated recoverable volumes to ll6Million Barrels according to Afren. The wells were not tested.  The updated value, however,” is based on reservoir modelling work currently underway”, the report contended.

“Completion of Ebok-6 appraisal well represents the successful conclusion of the pre-development Ebok appraisal phase (Ebok-4, Ebok-5 and Ebok-6 wells)”, an Afren release noted.

The latest well has significant input in the claimed upsurge in reserves. The company’s prognosis of estimated recoverable reserves in Ebok 6 was eight (8) million barrels (MMBbls) . By the time the well was completed and the results came in, the recoverable reserves in  Ebok-6 recoverable reserves had increased to 23MMBBO.

The First phase of Ebok field Development underway with five horizontal oil production wells in the D2 reservoir.

GABON: M&P Flows 3,000BOPD In Omoueyi Wildcat

Maurel et Prom flowed 3,000 BOPD on 140/64” choke tests in OMGW-1, a newfield wildcat in Gabon. The well head pressure during the test was 550 psi, With a slightly lower choke size of 32/64”, the well flowed l,500BOPD. OMGW-1, located in the Omoueyi exploration permit, was drilled to a depth of 1,765 meters where it encountered the “Grès de base” play and saturated hydrocarbon reservoirs wire perforated.

Maurel et Prom said that the encountered reservoirs showed excellent permeability and porosity characteristics. The company is conducting an additional seismic survey which will be used to build a development scenario. A request for Exclusive Development Authorization will he submitted to the authorities in H1 2010. Prior to the request the company  will ask for a three-month production test.

CAMEROON: It’s 300 Ft. Gross at La-105

Victoria Oil & Gas (VOG) reached a total depth of 2,718 metres(8,920 feet) in La-l05 well, on the Logbagba field in Cameroon on January 1, 2010. As of the time of our going to press on January 15, 2010, the latest announcement was that the well was being logged, prior to its completion as a development well. VOG says that multiple gas-bearing sands were encountered at virgin pressures at depths between 1,800 metres and 2,500 metres, which can be correlated to those found and tested in the nearby well La-103. Well La-103 flowed at rates from 5 to 12 million cubic feet of gas per day from individual sands when drilled in 1956.

The data obtained while drilling La-105 showed in excess of 300 feet of gross pay and also indicated the presence of over-pressured shale gas in a significant interval. VOG expected to run a 7-inch liner will be run to isolate the sands for future testing and production. The company was expected to provide more detailed information on La- 105 and drilling of the next well at Logbaba, La-106 in due course. But Kevin Foo, VOG Chairman as very upbeat. “Notably, the presence of gas in the shale could add upside to previous management interpretations”.

Why Chevron Opts For Expensive 4D Shoot For Agbami

Seabird’s Hugin Explorer, meant to acquire 4D (Timelapse Three Dimensional) seismic data on the deepwater Agbami field off Nigeria, hadn’t started work as of mid October 2009, because the contract papers hadn’t been finalized. But officials of the state hydrocarbon company NNPC have explained why the Agbami 4D data acquisition will be the most expensive deepwater seismic data gathering on a single field in the country. “Difficulty in reservoir characterization in the Agbami field made operator Chevron opt for a seismic acquisition technology that lays emphasis on capture of as much data as possible”,  the NNPC officials indicate.

“The nodal analysis type of acquisition is far more expensive than conventional data acquisition used for Time lapse 3D seismic (or 4D) on similar Nigerian deepwater fields. including Bonga”, the country’s flagship deepwater pool. “But Chevron wanted to use this acquisition to get a new set of baseline parameters to which future time lapse 3D will be referenced”. Agbami field development was slowed down considerably by poor understanding of the reservoir, even as the field’s first oil date loomed. The shoot will take six to eight months to complete and will cover about 586 sq km of area.

Agip Missed The Target In Oberan 2

Agip missed the expected reservoir in Oberan -2, inspite of the large expectations created by the discovery well. Oberan -2 is located in the Agip operated Oil Mining Lease (OML)134. Delays in the approval of contract for the three dimensional seismic acquisition, led the company to go ahead and drill the appraisal well, taking advantage of an available rig. “They thought they had enough information with the existing Agip seismic data to drill the appraisal”, a source said. They were wrong. Lessons learned: “They are going to take their time with the third well, integrate all available data into the new 3D data on the structure and evaluate. Oberan 3 is not likely to be drilled until the second or third quarter 2010”.

Hess Chews Dust in the Tano

In Ghana, Hess has completed drilling operations on the Ankobra-1 well, located on the Deepwater Tano Cape Three Points license, without encountering commercially significant hydrocarbons. The well was drilled to a depth of 3962metres in 1732metres of water. Hess holds a 90 percent interest in the license in partnership with Ghana National Petroleum Company. Hess is currently acquiring 1618 square kilometres of new 3D seismic in anticipation of a well to be drilled in the unexplored western half of the license areas.

Uganda: Buffalo Is The Biggest In Butiaba

Heritage Oil ‘s rank wildcat Buffalo-1, a new discovery in the Butiaba region of Block 1 in Uganda, is potentially the largest in the Butiaba Area to date. The well encountered 15 metres of net gas pay and over 28 metres of net oil pay within a 123 metre gross interval. The well was in an early stage of evaluation as of December 2008.

Buffalo-1 was drilled some 500 metres from the crest of the structure to a total depth of 637 metres. Downhole pressure testing and sampling confirmed the presence of dry gas and moveable oil that has been recovered to surface. The company says that reservoir quality in all pay zones is excellent, with the gas and oil columns encountered being 48 metres and 75 metres respectively with the potential to be even larger.

Executives at Tullow Oil, which is partner to Heritage Oil on the lease, enthuse that “Buffalo-1 is the fifth successful test of the Victoria Nile delta play fairway within the Lake Albert Rift Basin”. It was drilled 16 km north-east of the Warthog-1 and Kasamene-1 discoveries. This latest result extends the play further north and de-risks several adjacent prospects, located in Blocks 1 and 2, which are scheduled for drilling in 2009.

The well has now been suspended as a future producer and the rig moved five km south to the location of the Giraffe prospect where drilling commenced in late December 2008. This well will also appraise some of the upside potential of the Buffalo discovery.

Tullow has interests in three licences in the Lake Albert Rift Basin in Uganda. Tullow operates Block 2 with a 100% interest and has a 50% interest in Blocks 1 and 3A which are operated by Heritage Oil (50%).

SOMALIA: Africa Oil Completes Somalian Shoot

Africa Oil has successfully completed a 2D seismic survey in the Dharoor Valley of Puntland Somalia. A total of 782 km of vibroseis data, comprising a grid of 15 lines, were recorded by IMC Geophysical of the UK.

The Company will now process the new survey and combine the 555 km of earlier data into its seismic database. Mapping of this combined survey should commence in early 2009 and drilling locations will be selected before the end of Q1, 2009. This will permit mobilization of a drilling rig to fulfill the company’s drilling obligations under the Production Sharing Agreements before the end of 2009.

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