FILE PHOTO: Pump jacks operate at sunset in Midland, Texas, U.S., February 11, 2019. REUTERS/Nick Oxford

(Reuters) - The value of U.S. oil and gas mergers and acquisitions reached a five-year peak of $96 billion in 2019 on the back of competing bids for Anadarko Petroleum, energy data provider Enverus said on Thursday.

Occidental Petroleum Corp's OXY.N $38 billion acquisition of Permian rival Anadarko countered a pullback in corporate deal-making the sector, driven by investor pressure to prioritize shareholder returns over growth, Enverus said.

Occidental last year won a takeover battle for Anadarko, topping Chevron Corp's CVX.N $33 billion offer, after Berkshire Hathaway Inc's BRKa.N Warren Buffett and France's Total SA TOTF.PA came to its aid.

Without that acquisition, the total value of deals in 2019 would have been $39.1 billion, well below the $85 billion recorded in 2018, according to Enverus. The data provider valued the Anadarko deal at $57 billion, including debt taken on by the acquirer.

“Investors who funded the shale revolution over the last decade have become vocal in advocating for payouts and cut back on providing new capital. That flowed through to limited M&A and a negative reaction to deals for much of the year,” said Andrew Dittmar, senior M&A analyst at Enverus.

However, the total M&A spend in 2019 was the highest since 2014, when oil prices peaked at $112 per barrel before beginning a slump that saw prices drop by half of that.

Most of the last year’s marquee deals focused on the Permian basin of Texas and New Mexico, which is at the heart of the shale boom that has helped the United States become the world’s biggest producer of crude oil.

Enverus predicts M&A would rise this year, after ticking up in the fourth quarter of 2019, as smaller players with good land but less access to capital are gobbled up by those with free cash flow.

Apart from Occidental-Anadarko, 2019's largest corporate deals in the sector were Callon Petroleum Co's CPE.N $2.7 billion merger with Carrizo Oil & Gas Inc, WPX Energy Inc's WPX.N $2.5 billion buy of Felix Energy, and Parsley Energy Inc's PE.N $2.3 billion acquisition of Jagged Peak Energy JAG.N.