Exploration hotspot: Suriname

2021 to build on 2020 breakthrough

2020 was a breakthrough year for exploration offshore Suriname. Efforts to prove the extension of the Cretaceous fan play from neighbouring Guyana had proved elusive until the Maka Central-1 discovery made by Apache in January last year. The well was drilled in Block 58, just across the maritime boundary from ExxonMobil’s prolific Stabroek Block and encountered light oil and gas in stacked Upper Cretaceous play . The company, together with 50/50 partner Total, continued to drill in the block throughout 2020, with three further discoveries to date. The JV has identified over 50 prospects across seven play types and has chartered two rigs to carry out an exploration and appraisal programme in 2021. Momentum is now building in the region, with Petronas also discovering hydrocarbons at the end of 2020 in its Sloanea-1 well in nearby Block 52. Meanwhile, Tullow Oil is due to drill the Goliathburg-Voltzberg North well in Block 47 in Q121 and ExxonMobil is expected to drill a well in Block 59 next year.

Since ExxonMobil’s 2015 Liza discovery in Guyana, a number of wells were drilled offshore Suriname without success. In 2017, Apache’s Kolibri-1 exploration well in Block 53 was deemed non-commercial and followed the failure of the company’s Popokai-1 well in Block 58 in 2015. Despite this, data from these wells gave the company valuable information about the source rocks in the region. Tullow established the presence of gas condensate in its 2017 Araku well in Block 54, but did not find a significant quantity of reservoir rocks. Kosmos Energy drilled two wells in 2018, with both the Anapai-1 well in Block 45 and the Pontonoe-1 well in Block 42 encountering high-quality reservoir, but no hydrocarbons, most likely due to trap failure.

In January 2020, Apache encountered 50m of light oil and gas (API 40o – 60 o) in the Campanian and 73m of 35o – 45o API oil in the deeper Santonian in Maka Central-1. The final target in the Turonian was not drilled after experiencing overpressure in the Lower Santonian. This has been followed with successes at Sapakara West-1 in April , Kwaskwasi-1 in August and Keskesi East-1 in January 2021. Apache considers the Kwaskwasi-1 well the most successful to date, with the highest net pay of all three wells at 279m, together with the best quality reservoirs and oil and gas condensate of 35o- 45o API in the Campanian. The company has yet to provide estimated resources for these discoveries. The Keskesi East-1 well, 14km to the south east of Sapakara West-1, encountered 63m of hydrocarbons, with 58m of 27o -28o API in the Campanian and 35o -37o in the Santonian. Drilling is currently continuing into deeper targets.

This will be followed by the BonBoni exploration well in the north-eastern corner of the block. It will be the first well of the current programme to step away from the NW-SE trend of discoveries from Stabroek into Suriname and will target a play with multiple targets and source rocks, in a shallower reservoir but in deeper water than the wells drilled so far. Apache may also drill beyond the Campanian and Santonian intervals and into the Turonian in BonBoni.

Two deepwater rigs, the Maersk Developer and Maersk Valiant are being lined up to continue exploration and appraisal drilling in Block 58 in 2021. In addition to drilling BonBoni, the programme is expected to include appraisal drilling at Kwaskwasi, Maka Central and Sapakara.

And now Petronas has added to these discoveries, with the Sloanea-1 well having intersected several hydrocarbon bearing sandstones in the Campanian in December last year. Petronas is partnered in Sloanea-1 by ExxonMobil after it farmed into 50% of the block in May 2020, and the JV plans to acquire 6200km2 of 3D seismic across the licence in 2021.

ExxonMobil is not the only major to have farmed into the region in 2020, with Shell stepping in in September last year to take over a number of frontier assets from Kosmos, including a 50% operated interest in Block 45 and a 33.33% stake in the Chevron operated Block 42.

Tullow will also return to drilling in the region with the Goliathberg-Voltzberg North-1 (GVN-1) well in Block 47 due to spud in Q1 2021. GVN-1 will be located on the flank of Demerara High, and will target over 400mmboe gross in dual Upper Cretaceous turbidites.

As interest in the region has increased, Suriname launched a licensing round for eight shallow water blocks in November 2020, promoting the area as a link between the onshore producing fields and the Block 58 discoveries. The ongoing activity should ensure that Suriname remains a focus of industry attention in 2021 and beyond.