Energen Corporation. The Group's principal activity is to acquire, develop, explore and produce oil, natural gas and natural gas liquids in the continental United States. It also purchases, distributes and sells natural gas in the central and north Alabama. The natural gas is purchased through interstate and intrastate marketers and suppliers. This is then distributed to residential, commercial and industrial customers and other end-users of natural gas. Natural gas distribution accounted for 63% of 2002 revenues and Oil and gas operations, 37%.