Vinson & Elkins is assisting C. William Giraud, vice president, general counsel and corporate secretary of Midland-based Concho Resources Inc., in the company’s pending acquisition of Marbob Energy Corp. for $1.65 billion in cash and Concho securities.

On July 20, Concho announced a definitive agreement to acquire all of Marbob’s oil and gas assets in the Permian Basin of southeast New Mexico, including approximately 2,300 drilling sites and an estimated 76 million barrels of proven oil reserves. Marbob is a privately held company based in Artesia, N.M. and is represented in the deal by James Haas, a partner in Losee, Carson & Haas in Artesia, N.M.