Aug 1 (Reuters) - U.S. shale companies Devon Energy Corp and Diamondback Energy Inc on Monday surpassed estimates for second-quarter profit, joining global oil majors in posting bumper earnings on red-hot energy prices.

Oil and gas prices have skyrocketed as sanctions on major producer Russia throttle supply amid a rebound in demand from pandemic lows thanks to economies reopening after restrictions.

Benchmark Brent futures have risen more than 140% over the past year and averaged around $114 per barrel during the second quarter, helping U.S. and European heavyweights Exxon Mobil, Chevron, Shell and TotalEnergies post record profits.

Both Devon and Diamondback sweetened the pot for investors by announcing higher returns, with Devon raising its quarterly dividend to $1.55 from $1.27 and Diamondback hiking share repurchases by $2 billion to $4 billion.

Shares of both the companies inched down in extended trading, after dropping more than 2% in Monday's session that saw oil prices settle 4% lower.

Devon and Diamondback also lifted their 2022 production forecasts.

Oklahoma-based Devon now expects production to average 600,000 to 610,000 barrels of oil equivalent per day (boepd) this year, up from its previous forecast of 570,000 to 600,000 boepd earlier, due to better-than-expected well performance and its purchase of Williston Basin assets.

Diamondback said it now expects production to range between 374,000 and 380,000 boepd this year, compared with a previous range of 369,000 to 376,000 boepd.

However, acquisitions and inflationary pressures also forced both companies to raise their capital expenditure forecasts.

Excluding items, Devon earned $2.59 a share, above analysts' estimates of $2.38 per share, according to Refinitiv data.

Diamondback's adjusted earnings of $7.07 per share also beat estimates of $6.58 per share. (Reporting by Shariq Khan and Ruhi Soni in Bengaluru; Editing by Devika Syamnath)