Total E&P Norge AS said it encountered an oil column in the Heimdal field in the central part of the sea that was nearly 70 feet thick.
The company said the preliminary estimates of the size of the discovery are between 3 million and 12.5 million barrels of recoverable oil.
The well is positioned in a region not known previously to contain oil and natural gas reserves. It's the first exploration well in a production license area dubbed 102F.
Total E&P Norge AS is the operator, with a 40 percent stake in a consortium that includes Norwegian energy companies.
"The licensees will assess the discovery together with nearby prospects with regard to further follow-up [on the discovery's full potential]," the company said.