LONDON – Coro Energy has conditionally agreed to take a 15% stake in the Duyung production-sharing contract (PSC) in the West Natuna basin offshore Indonesia from operator West Natuna Exploration Ltd. (WNEL).
The concession includes the Mako gas field discovery. Coro will pay a cash and shares consideration of $4.8 million and contribute $10.5 million toward this year’s planned 2019 drilling campaign.
Shareholders of WNEL are Singapore-based Conrad Petroleum and AIM-listed E&P company Empyrean Energy.
Coro described Mako as a large, shallow structural closure, extending more than 350 sq km (135 sq mi). The reservoir is a Pliocene-age sandstone, with a gas-water contact at 391 m (1,283 ft) TVDSS.
Seismic definition is strong, with clear DHIs.
Although the field was not tested by prior operators, WNEL’s Mako South-1 well in 2017 proved a viable case for a development, Coro said.
The well, drilled to core and test the Mako reservoir, test flowed up to 10.8 MMcf/d of dry gas. Four wells to date have penetrated the reservoir section, with further appraisal is planned to determine the field’s areal extent of the field.
Mako is 16 km (9.9 mi) from the WNTS pipeline system that supplied gas from Indonesia to Singapore. The partners have submitted a plan of development to the Indonesian authorities and initiated gas marketing discussions, signing a heads of agreement with a buyer in Singapore.
Gaffney Cline & Associates estimates gross resources in the range 184-392 bcf.
Current plans call for an initial four-well development, a small platform with compression facilities and four further wells under a second phase later in the field’s life. Plateau production should be up to 90 MMcf/d.
In addition, the partners have mapped various prospects below and above the Mako field, notably Tambak, a Lower Gabus structure beneath the northern end of the Mako field, which could hold 200-300 bcf.
During December, Coro agreed to conduct a joint technical study with Petronas over block 2A offshore Sarawak, Malaysia, with the prospect of subsequently applying for a PSC for the concession.
There has been no drilling to date on the deepwater block, with the nearest discovery around 70 km (43 mi) to the east, although various large structural closures at prospective levels have been identified, consistent with known regional plays in this part of the basin, the company said.