Abstract: Compositions useful in the fracturing of subterranean formations are prepared by incorporating aluminum salts of one or more aromatic phosphoric acid esters in an oil base fluid. The salts can be formed separately followed by addition of the salt to the oil, or the salt can be formed in situ by separately adding to the oil an aromatic phosphoric acid ester and an aluminum compound which reacts with the ester to form the salt. In fracturing a subterranean formation, the fracturing composition is introduced into an oil or gas well, and from the well bore into the formation to form and propagate a fracture in the formation.