The definition of the continental shelf and the criteria by which a coastal State may establish the outer limits of its continental shelf are set out in Article 76 of the Convention. In addition, the Third United Nations Conference on the Law of the Sea adopted on 29 August 1980 the "Statement of Understanding" concerning a specific method applicable to such special features as those in the southern part of the Bay of Bengal. This Statement is contained in Annex II to the Final Act of the Conference.
Geologists use the term “continental shelf” generally to mean that part of the continental margin that is between the shoreline and the shelf break or, where there is no noticeable slope, between the shoreline and the point where the depth of the superjacent water is approximately between 100 and 200 metres.
However, this term is used in Article 76 as a juridical term. According to the Convention, the continental shelf of a coastal State comprises the submerged prolongation of the land territory of the coastal State - the seabed and subsoil of the submarine areas that extend beyond its territorial sea to the outer edge of the continental margin, or to a distance of 200 nautical miles where the outer edge of the continental margin does not extend up to that distance. The continental margin consists of the seabed and subsoil of the shelf, the slope and the rise. It does not include the deep ocean floor with its oceanic ridges or the subsoil thereof.
According to Article 76, the coastal State may establish the outer limits of its juridical continental shelf wherever the continental margin extends beyond 200 nautical miles by establishing the foot of the continental slope, by meeting the requirements stated for the thickness of sedimentary rocks, by satisfying geomorphological requirements and by meeting distance and depth criteria, or by any combination of these methods (Article 76, paragraphs 4 - 7).