Marathon Oil Corp. beat analysts' estimates for first-quarter profit on May 1, boosted by higher production and lower costs at its U.S. shale assets in the Bakken and Permian Basin regions.

Total oil production averaged 203,000 net barrels per day (bbl/d) in the first quarter, up 6% from a year ago, with U.S. crude production jumping 11%, adjusted for divestitures.

On the back of rising production from its assets and a rebound in oil prices, Marathon expects second-quarter total oil production of 200,000 to 220,000 net bbl/d, with U.S. oil production of 180,000 to 190,000 net bbl/d.

U.S. unit production costs fell 12% to $5.21 per barrel of oil equivalent due to ongoing cost reductions across the U.S. resource basins, particularly in the Northern Delaware Basin within the Permian, Marathon said.

The company has been looking to divest its North Sea assets and focus on the rising shale oil production in the U.S.

RELATED: Marathon Oil Signs Agreement For Divestiture Of UK Business

The oil and gas producer's net adjusted income rose to $256 million, or 31 cents per share, in the quarter ended March 31 from $154 million, or 18 cents per share, in the year-ago quarter.

Excluding items, earnings were 11 cents per share, beating the average analyst estimate of 7 cents, according to IBES data from Refinitiv.

The company's shares were up 1.3% in extended trading.