Outer Continental Shelf

In the Outer Continental Shelf Lands Act (OCSLA), the term “Outer Continental Shelf” (OCS) is defined as “(1) all submerged lands lying seaward and outside of the area of lands beneath navigable waters as defined in the Submerged Lands Act, and of which the subsoil and seabed appertain to the United States and are subject to its jurisdiction and control or within the exclusive economic zone of the United States and adjacent to any territory of the United States; and (2) does not include any area conveyed by Congress to a territorial government for administration (43 USC 1331).” 

State Jurisdiction

For most coastal states, the extent of their State Jurisdiction is three nautical miles (nm) from the coast line. Exceptions to this are Texas, the Gulf coast of Florida, and the Commonwealth of Puerto Rico where jurisdiction extends nine nm from shore. In some cases, the Submerged Lands Act (SLA) coast line differs from the baseline, e.g. when the U.S. Supreme Court fixes (immobilizes) an SLA boundary by judicial decrees.

Federal Jurisdiction

Federal Jurisdiction is defined under accepted rules of international law. Specifically, under international law, the continental shelf extends to the outer edge of the continental margin, or to 200 nm from the baseline, whichever is greater. Where the outer edge of the continental margin extends beyond 200 nm from the baseline, the outer limits of the continental shelf are determined in accordance with Article 76 of the 1982 United Nations Convention on the Law of the Sea.

The outer limits of the U.S. continental shelf, in areas beyond 200 nm, are established by the U.S. Extended Continental Shelf Project led by the Department of State, the Department of the Interior, and the National Oceanic and Atmospheric Administration (NOAA).   

U.S. OCS areas

OCS RegionAcreage
(in millions)
Alaska 1,047.17
Gulf of Mexico159.36
Puerto Rico, U.S. Virgin Islands, & Other Territories49.63
Hawaiian Islands & Midway Atoll609.12
Pacific Territories825.83
Totals 3,169.21