Morton-Thompson D., Woods A.M. (ed.) Development Geology Reference Manual

The American Association of Petroleum Geologists, 1992. — 549 p.The United States and the individual states have followed a legal system based on Roman law, which allows private ownership of oil and gas interests. Nevertheless, the federal and state governments control the leasing of about one-third of the oil and gas interests underlying the onshore landmass of the United States (estimated at 2.2 billion acres). They also control 100% (97% federal and 3% state) of the offshore areas of the United States (estimated at 885.6 million acres). In additional, 54 million acres of Indian lands are subject to U.S. government leasing control, and leasing rights to 44 million acres in Alaska are controlled by Alaskan natives (Mineral Management Service, 1989; Petroleum Independent, 1991).