Five years ago, explorers at a Norwegian oil company called Aker BP had a contrarian idea. They believed there might be a lot of oil lurking in an offshore natural gas field that was thought to be played out, and they persuaded Aker BP to let them go after this “missing” oil.

Their hunch has paid off in significant oil discoveries. In recent months, for instance, Aker BP has located a series of troves, known collectively as Omega Alfa, that may produce more than 130 million barrels of recoverable oil, the largest find in Norwegian waters this year.

“It was an intense summer for most of us,” Hanna Tronstad, a drilling superintendent, said while monitoring screens at the control center for the exploration work in a former hotel in Trondheim, a Norwegian port city.

In making the discoveries, Aker BP’s explorers not only tested intellectual concepts, but also pushed physical limits, drilling horizontal wells nearly seven miles long, a record for Norway.

Norway supplies roughly 30 percent of Europe’s natural gas demand and around 15 percent of its oil, according to Wood Mackenzie, a consulting firm. Those volumes help give it great strategic and economic importance, especially with reduced energy flows from Russia because of the war in Ukraine.