Anadarko Petroleum Corp. is an independent exploration and production company. Its asset portfolio includes positions in onshore resource plays in the Rocky Mountains region, the southern U.S. and the Appalachian basin. The company is also an independent producer in the deepwater Gulf of Mexico, and has production and exploration activities worldwide including positions in East and West Africa, Algeria, China, Alaska, and New Zealand. The company operates through three segments: Oil and gas exploration and production, Midstream, and Marketing. The Oil and gas exploration and production segment explores for and produces natural gas, crude oil, condensate, and natural gas liquids. The Midstream segment engages in gathering, processing, treating, and transportation services to the company and third-party oil and natural gas producers. It owns and operates gathering, processing, treating, and transportation systems in the United States. The Marketing segment sells most of the company's production, as well as production purchased from third parties. It markets oil, natural gas, and natural gas liquids in the United States, Algeria, China and Ghana. Anadarko Petroleum was founded in 1959 and is headquartered in The Woodlands, TX.