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Cote D’Ivoire: Rialto Completes Gazelle Well With “Good Gas Rate”

Rialto, the AIM listed minnow, has Rtested gas flow rate of 19.5 million standard cubic feet per day (19.5MMsf/d) of gas aswell as 133 barrels of condensate per day (133BCPD) in its first operated well in Block Cl-202, offshore Cote
d’Ivoire.
Rialto has now completed the Gazelle-P3 ST2well testing programmeand the well will now be suspended for future use.
The company reported that 40 API Oil was recovered at an unstabilised rate of 760 BOPD prior to well ‘channelling’ gas. “The flow rates confirm productivity of UC-1 reservoir sands”, a press release said.
“The maximum gas flow rate was constrained due to downhole equipment limitations. The estimated deliverability of the reservoir with standard 4.5″ production tubing rather than the 3.5″ test string is 33MMscf/d”, Rialto said. “The main DST focused on the Upper Cenomanian (UC-1C) gas reservoir (over the interval 2632.9-2666.6 mMDRT), successfully achieving an average flowrate during a ten hour period of 17.5 mmscfd gas through a 44/64” choke,
with a flowing wellhead pressure of 1470 psia”.
Prior to undertaking the oil test, cement bond logs indicated that the zones may not be hydraulically isolated in the well bore. As a result, the UC-1A oil reservoir (perforated over the interval 2678.0- 2713.2 mMDRT) achieved an unstabillised flow rate of 760 BOPD before gas, originating from the overlying gas reservoir via behind-casing
channelling, prevented further oil flow from this interval.


Tanzania: Papa-1 Finds Lots More Gas In Ruvuma

The BG/Ophir consortium topped up Tits gas reserves off Tanzania via the Papa 1, in Block 3, in the Ruvuma
Basin. The work is part of the Blocks 1, 3 and 4 drilling programme,operated by BG.
The Deepsea  Metro 1 (UDW Drillship) completed operations at the Mzia-1 discovery (Block 1) on 21 May and the vessel then moved to the Papa-1 location in Block 3. Papa-1 was spud on May 29 and is estimated to take 65 days to complete. Papa-1 targeted the Upper Cretaceous intra-slope channel play within the Rufiji delta. “The
Papa-1 prospect has an unrisked mean estimated recoverable resource of 3.1 Tcf (517 MMboe)”, Ophir said in a release.
Deepsea Metro 1 was expected to proceed to work for American operator, Apache on a single well in Kenya on acreage adjacent to Ophir’s Blocks L9 (60%) and L15 (100%), before returning to continue operations with the Ophir-BG Joint Venture


Frank Timis Threatens To Drill

LIBERIA

Will he or won’t he? That is the question, as Frank Timis, chairman of African Petroleum Corp., says his company plans to start drilling for oil off the coast of Liberia in March 2011.

APC has completed a seismic survey of its two exploration blocks, but Mr Timis looks like the kind of operative who would rather get other companies to operate and fund the E&P programme of an asset he has acquired.

Timis told the press that APC plans to bring a floating rig to drill two wells in the area, 48km off the coast and that drilling will cost $100 million.

This magazine’s guess is that March 2011 will come and APC still will not drill, unless one enthusiastic E&P company comes around to buy significant equity in those assets and goes ahead to drill. Since that had not happened by January 15, 2011, there’s no likelihood of APC being on the drill site off Liberia until late in the second quarter of 2011.

But announcements about plans to drill, such as the one that Mr Timis made in October 2010, only lead to pressure by the government of the country in which such assets are held. Right now, Mr Timis would be under pressure to proceed with his “drilling plans”. Liberia, for one, desperately wants “action” on exploitation of its resources. The West African nation is rebuilding its economy and infrastructure after a civil war that ended in 2003. Liberia is giving away its petroleum property to any company who can show sufficient enthusiasm to operate the property. That’s why the parliament approved an oil-exploration deal with California-based Chevron Corp. and Nigeria’s Oranto Petroleum Ltd(which has never spent money to drill a well any where).


Chevron Nigeria Is Drilling Again

KS Endeavour To Drill in Meji Field, Chevron Nigeria is returning from a drilling holiday in its prolific shallow water assets.

The California based oil major has contracted the rig KS Endeavour for drilling several wells in the shallow water Meji field in the western Niger Delta basin. “It marks a return of the company’s Joint Venture division to the drill- site and this is quite symbolic”, says Jeffrey Tolkein, an oil industry analyst based in Cairo. Chevron Nigeria’s drilling in the last six months had focused on the Agbami deepwater field. The company’s drilling activity in shallow water, swamp and land, have been on hold as the company focused on squeezing as much crude oil as it could, in areas to which it couldn’t gain access at the height of militant attacks. “Production, not drilling, has been top priority”, says Tolkein. “But for you to guarantee continued production, you have to return to the well site, either for workover, testing, or new drilling”. Chevron refrained from drilling in its swamp assets(Gbokoda, Benin River, Abiteye..) after attacks seven years ago, but has since refurbished the facilities and lined up plans to drill as many as 30 wells in the swamp area beginning in 2012. The shallow offshore, which had been the company’s main cash cow over the last 40 years, had continued to see drilling action, until the sudden stop in drilling in 2010. With the return to drilling operations in Meji and the expectations for swamp activity in 2012, Chevron Nigeria’s drilling activity should progressively rise in the next 15 months and help improve the country’s low rig count(16 rigs monthly average in 2010).


DNO Looks Forward To Inhaminga High

DNO is looking forward to a second well in the Urema Graben, onshore Mozambique, after the first well failed to encounter any hydrocarbon.  The company hopes it would crack the petroleum geology code in this underexplored formation with Ihaminga High 1, which it hopes to drill around February 2011.  Ihaminga High 1 is located east of Chite 1, the first well by DNO (or any other operator for that matter), in this graben.  Chite came up dry throughout its 3,050 metre depth.  “Information from the two well is supposed to allow valuables assessment of the hydrocarbon prospectivity and potential of the block”, DNO says in a statement.  The company is testing for source rocks, reservoir rocks and potential hydrocarbon trapping mechanisms.


Frank Timis Threatens To Drill

LIBERIA

Will he or won’t he? That is the question, as Frank Timis, chairman of African Petroleum Corp., says his company plans to start drilling for oil off the coast of Liberia in March 2011.

APC has completed a seismic survey of its two exploration blocks, but Mr Timis looks like the kind of operative who would rather get other companies to operate and fund the E&P programme of an asset he has acquired.

Timis told the press that APC plans to bring a floating rig to drill two wells in the area, 48km off the coast and that drilling will cost $100 million.

This magazine’s guess is that March 2011 will come and APC still will not drill, unless one enthusiastic E&P company comes around to buy significant equity in those assets and goes ahead to drill. Since that had not happened by January 15, 2011, there’s no likelihood of APC being on the drill site off Liberia until late in the second quarter of 2011.

But announcements about plans to drill, such as the one that Mr Timis made in October 2010, only lead to pressure by the government of the country in which such assets are held. Right now, Mr Timis would be under pressure to proceed with his “drilling plans”. Liberia, for one, desperately wants “action” on exploitation of its resources. The West African nation is rebuilding its economy and infrastructure after a civil war that ended in 2003. Liberia is giving away its petroleum property to any company who can show sufficient enthusiasm to operate the property. That’s why the parliament approved an oil-exploration deal with California-based Chevron Corp. and Nigeria’s Oranto Petroleum Ltd(which has never spent money to drill a well anywhere).


Will SOCO’s Third Change The Tide?

SOCO International is making a third attempt at getting a discovery in the Democratic Republic of Congo (DRC). The company came up dry in the two earlier wells. The third, Bayingu-1, located on the same onshore Nganzi Block as the earlier two, will be the deepest test, to be drilled to approximately 2,520 meters and is expected to take 25 days to reach the target depth.

The first well, Nganga 1 was drilled to 2,175 metres Measured- Depth, reaching the basement as prognosed and encountering “approximately 500 metres of source rock with significant hydrocarbon shows and approximately 245 metres of good quality porous sand with an average porosity of ca. 17.5% in the primary target”. Petrophysical interpretations of the logs dismissed the reservoirs as water wet, but SOCO looked at the bright side: “The predicted lateral seal for the reservoir horizon was not present because of the change in the basin margin adjacent to the well location which can now be seen to have provided a local sediment entry point for sands”. The company decided that the next well, in a different part of the basin with a different margin geometry, was to be located further away from this localised sand and is not expected to be impacted by it. In spite of this prognosis, however the Kinganga Nyanya 1, drilled to 1,164 metres Measured Depth was also a commercial disappointment, Still, SOCO had an explanation for its second back to back dry hole: “The well drilled good source rock shales in the middle and Lower Bucomazi, interbedded with Lower Bucomazi sands.  It also encountered the target Lucula formation sands although these were not hydrocarbon bearing’ SOCO says. “There were oil shows in the Lower Bucomazi and the Chela formations. Log analysis indicated oil pay in the secondary target Chela formation sands. Although the well bore was not ideally situated to encounter the thickest part of the Chela sands, an abbreviated test was carried out to determine the reservoir characteristic. On test the sands were found to be tight”.

SOCO claims that in spite of the lack of commercial discoveries of the earlier two “they confirmed the presence of oil and provide valuable data that will be used in further evaluation of the area”.


XOM Returns To Shoot Yoho

The American major Tenders For 3D Survey APSDM In OML 104 Seven years after a carpet seismic coverage, spanning 1,230km2 full fold, ExxonMobil(XOM) is returning to the Oil Mining Lease(OML) 104, offshore Nigeria, for a Strategic Imaging Project. The work, this time, is largely a rigorous processing of the data acquired in 2003. The company is looking at a combination of anisotropic pre-stack depth migration APSDM, combined with advanced velocity model and tomographic techniques, “to improve fault sag and fault shadow imaging problems in OML 104 and ultimately reduce the structural deeper (>10,000ft) exploration leads as well as at Yoho and adjacent fields”. Fault surfaces will need to be depth interpreted and become surfaces that separate velocity contrasts within the model. Anisotropic parameters will need to be constrained by available well control and checkshots (Vl and Walkaway) as well as geological surfaces. “Finding the proper combination of depth imaging algorithms and model building will require some trial and error testing’ XOM declares.

ExxonMobil wants a collaborative effort in technology breakthrough with contractors that work in this kind of area. “Success will require strong collaboration between specialized experts from the contractor and MPN(the Nigerian shallow water subsidiary of ExxonMobil)”.

The 2003 vintage data was acquired in a 10 streamer dual source configuration in an East West direction, into 12.5 xline bins with 6km streamers with a1-8-7-m-fIip flop source yielding 80 fold. Due to surface obstructions in the area, some 1500m offset box-in-data was also acquired in 2003. Additional vintage streamer data(different shooting direction) will also be used to supplement near offset gaps around obstructions. The imaging programme area includes the entire 2003 3D survey extent(1230km2 full fold. “Based on technical and business needs, a priority area of ‘262 km2 full fold(”125 km2 image area) is planned to be branched off later in the velocity model building phase.

The entire workscope can then be broken down into three categories:

• High end preprocessing from navigation merged field taps. Noise mitigation, multiple suppression and signal enhancement are critical, particularly in fault shadow areas. Bin and regularlisation of data prior to migration.

• Iterative Anisotropic Velocity Model Building to accurately resolve lateral velocity contrasts across faults for the entire OML 104 block. Contractor must have a full suite of proven prestack depth migration algorithms (Kirchoff, Beam, WEM, RTM) as

well as proven tomography with ability to constrain input rays based on model surfaces. Contractor must have the ability to incorporate the geological surfaces and other geophysical data into the velocity/anisotropic model

• Hi end post-migration processing and noise reduction as required with a suite of angle stacks and specialized derivative volumes.


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.

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