Continental shelf

Shelf, continental shelf, continental shelf, continental shelf are names for the most rand union area of a continent, which is covered by sea. Such sea is called the shelf sea. Presented this shelf sea relatively far into the interior of the continent, one also speaks of a Epikontinentalmeer ( " on the continent befindliches sea ").

  • Shelf areas of the earth

Term origin

The term shelf was introduced at the latest in 1902 by the geographer Otto Krummel in the German -language literature. This is the Eindeutschung of the English word shelf, which was, according to Krummel, 1887 first used by the Scottish geographer and meteorologist Hugh Robert Mill in the continental shelf combination. Crumbs even rewrote the shelf as " cornice Seerande on the continental shelf ." [Note 1]

Oceanography

In morphologically - oceanographic sense it is at a shelf to a low seaward sloping platform that is up to 200 meters below sea level. Since this is very little compared to the average depth of the oceans, the sea shelf is colloquially referred to as a shallow lake or shallow sea. The biologically highly productive shelf sea is the " nursery " of many species of fish and also overall very rich in various animal and plant species.

Depending on the geological conditions can be a narrow hem or a broad, ragged belt of the shelf. With 1500 kilometers of the Siberian continental shelf has the largest seaborne expansion. In the global average of the shelf area is about 74 kilometers wide. In periods of, among other glacially induced global sea level low stand, large parts of the continental shelf can dry out. The total area of ​​shelf seas then decreases drastically in part, which often leads to the extinction of species under the shelf dwellers. In the opposite case, when the sea level is rising due to the melting of the ice sheets at the poles of the world, many rather narrow shelves expand to so-called Epikontinentalmeeren. The maximum depth of the shelf seas is in these periods also more than 200 meters.

Landward of the shelf is limited by the Schorre, seaward it is the shelf edge - a line from which the slope of the seabed significantly increased. On the shelf edge seaward follows the continental slope, followed by the deep sea at the end, the continental rise.

Geology

The shelf area is part of the continental mass, since its subsoil consists of continental crust. On the shelf, typical ( neritic ) sediments are deposited, which are labeled according to their depositional environment as shelf sediments. Especially in tropical and sub-tropical shelf seas it comes to predominantly biological formation of carbonates. The "carbonate factory", that is, the community directly or indirectly carbonate producing organisms, achieved in the tropical shelf seas their highest productivity. At relatively low input of nutrients and suspended solids therefore form on tropical Schelfen typical carbonate platforms with reefs.

Both the current and the shelf platforms today located on the mainland shelves of the geological past are areas with significant oil and gas deposits. Example of natural gas deposits in recent Schelfen are eg the North Sea and the northern Gulf of Mexico. The oil and natural gas properties in Texas and on the Arabian Peninsula go back to the now defunct shelf seas of the Permian Basin and the Tethys Ocean.

Legal

The continental shelf (English continental shelf) is in the legal sense is one of the UNCLOS ( UNCLOS) defined marine zones. The continental shelf is not part of the territory of the coastal state ( territorial sea ); but the coastal State exercises sovereign over the continental shelf rights for the purpose of exploring it and exploiting its natural resources (see article 77, paragraph 1 UNCLOS ). No one may explore or exploit the continental shelf without the express consent of the coastal State. In practice, this concerns in particular the marine mining.

Demarcation

From the definition ago the continental shelf differs in zweierlein respect of the exclusive economic zone in accordance with UNCLOS: First, the term " continental shelf " refers exclusively to the seabed and subsoil, not to the overlying water or air column. Second, can protrude (200 -mile ) of the continental shelf on the extension of the Exclusive Economic Zone, which is limited to 200 nautical miles from the baseline, when the geomorphological conditions warrant it; please refer to Article 76, paragraph 4 UNCLOS. This possibility is based on the idea that the continental shelf is the submarine continuation of the mainland. The deep seabed beyond the continental shelf and the resources found there, however, are permanently withdrawn after UNCLOS claims to sovereignty of individual coastal states and are considered as the common heritage of all humanity (see Article 136 ).

History, Politics

In contrast to the exclusive economic zone, which is a construct of UNCLOS 1982, the continental shelf is historically to the so-called " Truman Proclamation " back, with the United States in 1945 as the first state claimed the economic use of their continental shelf. In the following decades, this idea quickly became customary international law and led to the Geneva Convention on the Continental Shelf of 29 April 1958. Below proclaimed a number of states, including the Federal Republic of Germany ( January 20, 1964) a continental shelf. In the course of technological development ( opportunities to ocean mining ) and the simultaneous shortage of raw materials, the use of the continental shelf is gaining political importance and leads to increased use of fields as continental shelf by States, for example, the People's Republic of China in the event of the Senkaku islands (see Law of the Sea ).

Continental shelf of the Federal Republic of Germany

The establishment of a continental shelf in the Baltic and the North Sea is due to the proximity of the other riparian countries and because both shallow seas with depths less than 200 m are difficult. The boundary in the North Sea has long been controversial. They finally took place through bilateral agreements on the basis of the judgment of the International Court of Justice on the so-called North Sea Continental Shelf Case (1969). Result of these provisions is the so-called " duckbill ". In the Baltic Sea, the delimitation of the German continental shelf based on bilateral agreements with Denmark and Sweden on the basis of Äquidistanzprinzipes.

List of contracts for the continental shelf of the FRG

  • UNCLOS of 10 December 1982 German version, for example, in: Shipping Law: law of the sea laws, regulations, conventions MAP Handelsgesellschaft mbH, Hamburg, 1998, ISBN 978-3980122214
  • Agreement on the delimitation of the continental shelf under the North Sea between the Federal Republic of Germany and the Kingdom of Denmark (Federal Law Gazette 1972 II p 882 )
  • Agreement on the delimitation of the continental shelf under the North Sea (Federal Law Gazette 1972 II p 882 ff ) between the Federal Republic of Germany and the Kingdom of the Netherlands ( Federal Law Gazette 1972 II p 889 ff )
  • Agreement on the delimitation of the continental shelf under the North Sea between the Federal Republic of Germany and the United Kingdom of Great Britain and Northern Ireland on 25 November 1971 ( Federal Law Gazette 1972 II p 897 ff )
  • Diplomatic exchange of notes of 26 Mai/28. December 1976 between the Federal Republic of Germany and the Kingdom of Denmark on the delimitation of the continental shelf in the Baltic Sea
  • Proclamation of the government of the GDR over the continental shelf on the Baltic coast. From 26 May 1964. Coll 1964, Part I, No. 6, pp. 99
  • Treaty and the Protocol between the GDR and the Kingdom of Sweden on the delimitation of the continental shelf of 22 June 1978 ( Journal of Laws of 1979, II, p 39)
  • Treaty and the Protocol between the GDR and the Kingdom of Denmark on the delimitation of the continental shelf and fisheries zones of 14 September 1988 ( Journal of Laws of 1989, II, p 147)

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