The Delimitation of the Continental Shelf

Shorelines are not the geographical boundary of coastal States, as their jurisdiction extends under the sea to the edge of what is known as the continental shelf. The continental shelf is not a mere legal fiction, it is comprised of physical and palpable elements, such as sand, and different substrates. 

The 1982 United Nations Convention on the Law of the Sea (UNCLOS) defined the concept of the continental shelf and established the rules for delimiting the outer limits of the continental shelf. Article 76 of UNCLOS declares that the continental shelf of coastal States includes: "the seabed and subsoil of the submarine areas that extend beyond its territorial sea throughout the natural prolongation of its land territory to the outer edge of the continental margin, or to a distance of 200 nautical miles from the baselines from which the breadth of the territorial sea is measured where the outer edge of the continental margin does not extend up to that distance".[1] On the other hand, coastal States may delimit their continental shelf beyond 200 nautical miles if the Commission of the Limits of the Continental Shelf approves their claim after evaluating the evidence.[2]

Valuable minerals are buried in the continental shelf, including oil,[3] which humans have tried to extract since the late 1930s.[4]  In 1945, the possibilities of seizing the riches of the continental shelf prompted U.S. President Harry S. Truman to issue a proclamation in which he unilaterally declared that "the Government of the United States regards the natural resources of the subsoil and the seabed of the continental shelf beneath the high seas but contiguous to the coasts of the United States as appertaining to the United States" and "subject to its jurisdiction and control".[5]  It is important to note that President Truman's proclamation did not define the concept of the continental shelf.[6]  States set out to define the boundaries of the continental shelf to establish a legal framework for exploiting the continental shelf resources. 

To shed light on the issue,  the international community once again tried to define the continental shelf. In 1958 the Convention on the Continental Shelf (CPS) was born, which defined the continental shelf.[8]   The CPS established that "the term "continental shelf" is used as referring (a) to the seabed and subsoil of the submarine areas adjacent to the coasts but outside the area of the territorial sea to a depth of 200 meters or, beyond that limit, to where the depth of the superjacent waters admits of the exploitation of the natural resources of the said areas; (b) to the seabed and subsoil of similar submarine areas adjacent to the coasts of islands".[9]  The definition turned out to be contradictory and caused debates among the international community since on the one hand, it established a specific limit of two hundred meters, and at the same time, it allowed the expansion of the limit as far as the exploitation of the resources was possible.[10]  Technological advances surpassed the limits imposed by the definition and again a new interpretation was needed.[11]

In search of a solution to determine the limits of the continental shelf, two new formulas were presented, the Soviet and the Irish.[12]  The Soviet formula established a fixed mileage of 300 nautical miles, while the Irish formula used the thickness of the sediment wedge and the distance seaward from the foot of the continental slope.[13]  Finally, the two proposals were combined to create a hybrid proposal called the Biscuit Formula, which was reproduced in Article 76 of the 1982 United Convention on the law of the Sea, [14] which defines the continental shelf of coastal State as the "seabed and subsoil of the submarine areas that extend beyond its territorial sea throughout the natural prolongation of its land territory to the outer edge of the continental margin, or to a distance of 200 nautical miles from the baselines from which the breadth of the territorial sea is measured where the outer edge of the continental margin does not extend up to that distance." [15]

There is no doubt that the concept of the continental shelf is complicated and its application requires an interdisciplinary approach. States with greater intellectual resources have the advantage of resolving the complexities of the continental shelf and producing technology to exploit the resources of their continental shelf. On the other hand, the potential of the continental shelf should encourage countries that do not yet have the resources to exploit their continental shelf to prioritize the development of their intellectual resources, so that they can manage, exploit and protect their continental shelf.

Footnotes

[1] U.N. Convention on the Law of the Sea art. 76(1), Dec. 10. 1982, 1833 U.N.T.S. 397.

[2] Francisco Lertora Pinto, Delineation Process of the Extended Continental Shelf - Proceso de Delineación de la Plataforma Continental Extendida, 47 Revista Chilena de Derecho 873, 874 (2020). (discussing the process for a Coastal state to establish a continental shelf beyond 200 nautical miles).

[3] Josef L. Kunz, Continental Shelf and International Law: Confusion and Abuse, 50 The Am. J. of Int’l Law 828, 829 (1956).

[4] Ted L. McDoorman et al., International Ocean Law 80, (2005).

[5] J. A. C. Gutteridge, The 1958 Geneva Convention on the Continental Shelf, 35 BRIT. Y. B. Int’l. 102, 103 (1959); Proclamation No. 2667, 10 Fed. Reg. 12303 (Sept. 28, 1945).

[6] Gutteridge, supra note 5.

[7] Ted L. McDorman et al., International Ocean Law 80, (2005).

[8] Gutteridge, supra note 5, at 105-06.

[9] Id. at 106.

[10] McDorman, supra note 7, at 81-82.

[11] Id. at 82.

[12] Makhhdoom Ali Khan, The Juridical Concept of the Continental Shelf, 38 Pakistan Horizon 19, 35 (1985).

[13] McDorman, supra note 7, at 83.

[14] Id.

[15] U.N. Convention on the Law of the Sea art. 76(1), Dec. 10. 1982, 1833 U.N.T.S. 397.