In addition to Uaru-2, three other discoveries offshore Guyana – Liza Deep, Tripletail and Yellowtail – have had deeper penetrations into the Santonian. That deeper interval is found not only at the prolific Stabroek Block, but also extends east into neighbouring Suriname. Apache, which has made four Suriname discoveries at Block 58, has penetrated the Santonian in all its wells.
Block 58 adjoins the Stabroek Block in neighbouring Guyana, where an ExxonMobil-led consortium has made over 18 discoveries since 2015 and in December 2019 became the first producer of oil in that country from its Liza field.
“Certainly, the Santonian has the potential to be a very large addition to the recoverable resources in Guyana,” Greg Hill, Chief Operating Officer at Hess Corporation said. “And that is another key objective this year, to get some more penetrations in [the Santonian] so we can begin to piece the puzzle together on that interval.”
Hess CEO John Hess has called the Santonian a “fairly massive sand section” while Hill has pointed out that it underlies the entire Liza complex.
“We’ve had four penetrations [in it] and coupled with Apache’s results we see that as very positive,” Hill said. “But we’ve got a lot more drilling to do to understand it.” One way is by deepening the “tails” on Campanian exploration wells, but also through some stand-alone Santonian penetrations, he said, adding at “least one” well will have the Santonian interval as its main objective.
Exploration drilling at Stabroek Block for the rest of 2021 will focus on both Liza-type Campanian reservoirs and on the deeper Santonian zones. Additionally, appraisal wells will target the southeast edge of the block. The Longtail, Mako and Turbot fields in that area will be appraised this year, helping to define the partners’ fifth and sixth Stabroek developments, said Hill.
Just this week, Stabroek operator ExxonMobil submitted the application for the 4th development at Yellowtail.