Oil and gas giant Royal Dutch Shell has agreed to buy US natural gas explorer East Resources for $4.7bn (£3.2bn).
The cash offer was made to East Resources and its private equity investor Kohlberg Kravis Roberts (KKR).
East Resources holds more than 650,000 acres in the Marcellus shale, a rock formation running from West Virginia to New York, said to have vast amounts of natural gas.
The deal is subject to regulatory approval.
KKR invested $350m in East Resources for a substantial stake only 11 months ago, according to the Wall Street Journal.
Shell also revealed it had bought 250,000 acres of mineral rights in the Eagle Ford shale in south Texas.
"These acreage additions form part of an ongoing strategy, which also includes divestments, with an objective to grow and to upgrade the quality of Shell's North America tight gas portfolio," Shell chief executive Peter Voser said.