Two rigs to step up drilling, completion at offshore Ghana fields

Tullow Oil aims to have five new wells onstream across its Jubilee and TEN fields offshore Ghana before year-end.

Offshore staff

LONDONTullow Oil aims to have five new wells onstream across its Jubilee and TEN fields offshore Ghana before year-end, lifting production through both sets of facilities.

Next year the company will drill more wells to sustain and maximize plateau production.

It is also evaluating additional exploration acreage in Ghana that will be made available in the country’s upcoming license round.

During 1Q, Tullow contracted a second rig, the drillshipStena Forth, for its ongoing development program. The contract covers an initial three wells with flexible extension options and is due to start in October, alongside the Maersk Venturer which began work in March.

The arrangement will allow Tullow to perform simultaneous drilling and completion activity, allowing tie-in of new wells to be advanced.

To date theMaersk Venturer has drilled two new Jubilee production wells, J51-P and J53-P, and these will be completed and brought onstream during the current and final quarters, with a previously drilled Jubilee water injection well also tied-in.

The field’s FPSO turret remediation project is entering its final phases. TheKwame Nkrumah was shut down twice earlier this year to stabilize the turret bearing, and the turret has now been secured to a newly installed bearing plate.

A final short shutdown at the end of the year will allow the FPSO to rotate to its permanent heading, accompanied by installation of the final spread mooring anchoring system.

In addition, the partners have agreed to install a catenary anchor leg mooring buoy for offtake from the FPSO, probably in 2020.

The first additional Ntomme well (Nt-05P) has been drilled and should start production next month. A second well should be completed around year-end, flowing from early 2019, at which time Tullow expects to be able to raise gross production to around 80,000 b/d.

During the Jubilee shutdown Tullow supplied substitute gas from the TEN fields to the Ghana National Gas Co. Commercial gas sales from TEN should begin later this quarter.

As for the company’s interests elsewhere in West Africa, the Chinguetti FPSO offshore Mauritania has been demobilized following the successful temporary suspension of 15 wells as part of the decommissioning program.

Off Mauritania, a 9,000-sq km (3,475-sq mi) 3D seismic survey across block C-18 has finished. Interpretation of results from this and last year’s block C-3 survey are in progress to identify prospects for future drilling, possibly in late 2019.

Tullow expects theOcean Rig Poseidon to spud the high-impact Cormorant prospect in the PEL37 license offshore Namibia in September. The well, expected to take around 30 days to drill, will target light oil, with other similar-size prospects nearby.

Offshore Peru, Tullow has agreed to acquire a 35% interest in block Z-38 through a farm-down from Karoon Gas Australia, although the arrangement remains subject to government approval. This is oil-prone acreage covered by 3D seismic – identified prospects includes Marina, which could be drilled next year.

To the north, Tullow has secured a two-year extension for block 47 offshore Suriname where the Goliathberg prospect is a drilling candidate for 2019. And the company is currently interpreting data from a 2,555-sq km (986-sq mi) 3D seismic survey over its acreage offshore Uruguay, completed last year.


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