The world’s oil and gas explorers discovered 12.2 billion barrels of oil equivalent (boe) in 2019, which is the highest volume since 2015, according to energy researcher Rystad Energy.

Rystad reported that 2019 saw 26 discoveries of more than 100 million boe, with offshore regions dominating the list of new oil and gas deposits.

Looking into company rankings, ExxonMobil came first in 2019 after it added four new discoveries within its offshore Stabroek block in Guyana.

Rystad’s upstream senior analyst Palzor Shenga said:  “ExxonMobil can be declared explorer of the year for a second year in a row thanks to its ongoing efforts and results in Guyana, along with significant investments in Cyprus. The supermajor was exceptional, both in terms of discovered volumes and value creation from exploration.”

Rystad also estimated that the discoveries in Guyana hold cumulative recoverable resources of around 1.8 billion boe.

Chinese CNOOC took the second and the third spots on the list of top explorers of 2019 in terms of value creation from new discoveries, benefiting from its partnership with ExxonMobil in Guyana’s Stabroek block. CNOOC had value creation of around $1.8bn for the time period.

French operator Total took fourth place, with about $873m in value creation from its 2019 exploration activities after the success with the Brulpadda find in South Africa, according to Shenga.

In turn, BP’s Orca gas field was the largest single discovery and also the deepest-water find of 2019, estimated by Rystad to hold about 1.3 billion boe of recoverable resources. Off the coast of Mauritania, recent gas discoveries in the region now support plans to build an additional LNG hub in the Bir Allah area.

In Russia, Gazprom announced two discoveries in the Kara Sea, Dinkov in the Rusanovsky block, the second-largest find in 2019 worldwide, and Nyarmeyskoye in the Nyarmeysky block. Rystad estimates the Gazprom discoveries for the period to hold combined recoverable resources of around 1.5 billion boe.

Other key offshore discoveries in 2019 include Total’s Brulpadda in South Africa, ExxonMobil’s Glaucus in Cyprus, CNOOC’s Glengorm in the United Kingdom and Equinor’s Sputnik in the Norwegian sector of the Barents Sea.

On the other hand, Shenga said that many of 2019’s high-impact wells turned out to be duds. “Although the discovered volumes for 2019 surpassed the preceding year, it was a disappointing year for high-profile wells as many prospects with significant estimated pre-drill resources failed to deliver.

Over 10 billion barrels of estimated pre-drill volumes were at stake in wells that failed to encounter hydrocarbons,” he said.

In 2020, Rystad expects the global discovered volumes to continue the recent trend, with the list including high-impact wells along with promising probes delayed from 2019.