Apache, Total Hit Oil Pay Offshore Suriname

[Editor's note: This article was updated Jan. 15.]

French major Total SA and partner Apache Corp. said Jan. 14 the Keskesi East-1 exploration well offshore Suriname has struck oil, bringing their discovery tally in the region up to four.

Drilled by the Noble Sam Croft drillship in a water depth of about 725 m, the companies said the well hit oil pay in the upper Cretaceous-aged Campanian and the deeper Santonian intervals.

The discovery continues to prove a working hydrocarbon system in multiple play types tested in the Suriname-Guyana Basin, which has already proven prolific for the Exxon Mobil Corp.-led consortium that has made 18 discoveries offshore neighboring Guyana.

Apache and Total said 58 m (190 ft) of net oil, volatile oil and condensate pay was encountered by Keskesi East-1 in the Campanian with fluid samples indicating API oil gravities of about 27 to 28 degrees. Higher API gravities, ranging from 35 to 37 degrees, were denoted in the deeper Santonian where the companies said 5 m (16 ft) of net oil and volatile oil pay was hit in the Santonian. Drilling started on Keskesi in September.

“We are very pleased to announce our fourth consecutive discovery in Block 58 at Keskesi, which confirms oil in the eastern portion of the block,” Apache CEO John Christmann said in a news release. “We are excited to commence the appraisal program on our initial discoveries and extend our Block 58 exploration program to the north in 2021.”

Total, which became operator of Block 58 where the well is located in January, is currently drilling deeper targeting Neocomian-aged reservoirs, the company said in a news release. Plans are for the Noble Sam Croft drillship to be released following completion of Keskesi East-1 operations.

The latest find follows discoveries at Maka Central, Sapakara West and Kwaskwasi—all of which made under Apache operatorship. The latter was called the team’s biggest discovery on the block, logging in 278 m (912 ft) of net oil and volatile oil/gas condensate pay in two intervals.

All three discoveries are located on Block 58 and successfully tested for the presence of hydrocarbons in multiple stacked targets in the upper Cretaceous-aged Campanian and Santonian intervals.

Bernstein analysts noted that of the four discoveries made by Apache on the block, the thicker ones were on the block’s west side—an observation that appears aligned with the basin’s depositional geometry.

The analysts said they believe the next well, set to be drilled by Total, will be more oil prone. “It is possible that the depositional environment will transition more towards basin floor fan than slope deposits (which in theory could provide for large more continuous reservoirs of thinner and potentially lower reservoir quality),” analysts said in the note.

Apache said the next well on Block 58 will be at Bonboni, which is in the north central part of the block.

Total tapped Maersk Drilling in November to provide two deepwater rigs—Maersk Developer and Maersk Valiant—for exploration and appraisal work offshore Suriname starting in early 2021, according to Maersk. The campaign has an estimated firm combined duration of 500 days.

“We are delighted to announce this new discovery, which confirms this first exploration campaign as a full success and adds to the proven resource base,” Kevin McLachlan, senior vice president of exploration for Total, said in a separate news release. “We are also excited, as new operator of the block, to start the appraisal operations designed to characterize the 2020 discoveries, while in parallel start a second exploration campaign on this prolific block in 2021.”