ExxonMobil posted a rare earnings miss st the weekend, the only international oil producer to do so last quarter, as production slipped in its African and Canadian operations.
Exxon's results were overshadowed by rival Chevron, which easily exceeded Wall Street's expectations with a double-digit percentage increase in production.
Royal Dutch Shell , Total and Statoil last week delivered profits that topped expectations also.
Chevron for years has downplayed profits to spend heavily on megaprojects in Australia, the US Gulf of Mexico and elsewhere.
That spending now is boosting Chevron's profit, whereas Exxon has fewer projects about to come online and many of its older assets require more capital to maintain.
While profit rose sharply from a year earlier, theTexas-based company's production slipped about 1 per cent.
"Exxon continues to really struggle on getting its output up," said Edward Jones analyst Brian Youngberg.
"Chevron is going from a cash spender to a cash generator, even without commodity prices improving," he said.
Exxon's stock was the worst drag on the Dow Jones industrial average, while shares of Chevron led the index higher.
Both companies said they would continue to deploy drilling rigs and other equipment to the Permian Basin, the largest U.S. oilfield.
That expansion, along with similar plans by other US shale peers, is likely to further irritate Opec, which have tried with mixed success this year to tame an oversupply of crude oil.
Exxon posted second-quarter net income of US$3.35 billion, or 78 cents per share, compared to $1.7bn, or 41 cents per share, a year earlier. Analysts expected earnings of 84 cents per share, according to Reuters.
Imperial Oil , which is majority controlled by Exxon and operates in Canada's oil sands region, posted a net loss, denting Exxon's results from that country.
Exxon's Kearl oil sands operations in Alberta were partly offline, hurting Canadian production.
Chevron boosted output by 10 per cent and cut its costs, part of what executives called a pivot to earnings growth.
The company reported second-quarter net income of $1.45 billion, or 77 cents per share, compared to a net loss of $1.47bn, or 78 cents per share, in the year-ago quarter.
Excluding one-time items, the company earned 91 cents per share. By that measure, analysts expected earnings of 87 cents per share, according to Reuters.
Chevron's cash flow dropped more than Exxon's, when compared to the same quarter last year, but with a steady stream of projects coming online, nearly all Wall Street analysts have said they prefer Chevron more than its Texas-based rival.
Chevron's Gorgon LNG project in Australia had suffered setbacks since coming online, including several temporary shutdowns earlier this year.
But those appear to be behind the company, and Chevron said its second LNG project in Australia, at Wheatstone, should be operational later this year, further boosting profit.