Continental shelf

Marine habitats
Southeastern United States continental shelf.jpg
Anatomy of a continental shelf of the south eastern coast of the United States

A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water known as a shelf sea. Much of these shelves has been exposed during glacial periods and interglacial periods. The shelf surrounding an island is known as an insular shelf.

The continental margin, between the continental shelf and the abyssal plain, comprises a steep continental slope, surrounded by the flatter continental rise, in which sediment from the continent above cascades down the slope and accumulates as a pile of sediment at the base of the slope. Extending as far as 500 km (310 mi) from the slope, it consists of thick sediments deposited by turbidity currents from the shelf and slope.[1] The continental rise's gradient is intermediate between the gradients of the slope and the shelf.

Under the United Nations Convention on the Law of the Sea, the name continental shelf was given a legal definition as the stretch of the seabed adjacent to the shores of a particular country to which it belongs.

Geographical distribution

  The global continental shelf, highlighted in cyan

The width of the continental shelf varies considerably – it is not uncommon for an area to have virtually no shelf at all, particularly where the forward edge of an advancing oceanic plate dives beneath continental crust in an offshore subduction zone such as off the coast of Chile or the west coast of Sumatra. The largest shelf – the Siberian Shelf in the Arctic Ocean – stretches to 1,500 kilometers (930 mi) in width. The South China Sea lies over another extensive area of continental shelf, the Sunda Shelf, which joins Borneo, Sumatra, and Java to the Asian mainland. Other familiar bodies of water that overlie continental shelves are the North Sea and the Persian Gulf. The average width of continental shelves is about 80 km (50 mi). The depth of the shelf also varies, but is generally limited to water shallower than 100 m (330 ft).[2] The slope of the shelf is usually quite low, on the order of 0.5°; vertical relief[clarification needed] is also minimal, at less than 20 m (66 ft).[3]

Though the continental shelf is treated as a physiographic province of the ocean, it is not part of the deep ocean basin proper, but the flooded margins of the continent.[4] Passive continental margins such as most of the Atlantic coasts have wide and shallow shelves, made of thick sedimentary wedges derived from long erosion of a neighboring continent. Active continental margins have narrow, relatively steep shelves, due to frequent earthquakes that move sediment to the deep sea.[5]

Other Languages
العربية: منحدر قاري
azərbaycanca: Şelf
беларуская: Шэльф
беларуская (тарашкевіца)‎: Шэльф
Deutsch: Schelf
eesti: Mandrilava
Ελληνικά: Υφαλοκρηπίδα
Esperanto: Kontinentbreto
فارسی: فلات قاره
한국어: 대륙붕
Bahasa Indonesia: Landas benua
íslenska: Landgrunn
עברית: מדף יבשתי
ქართული: შელფი
Kiswahili: Tako la bara
Kreyòl ayisyen: Plato kontinantal
lietuvių: Šelfas
Bahasa Melayu: Pentas benua
Nederlands: Continentaal plat
日本語: 大陸棚
norsk nynorsk: Kontinentalsokkel
русский: Шельф
Simple English: Continental shelf
slovenčina: Šelf
slovenščina: Kontinentalna polica
srpskohrvatski / српскохрватски: Epikontinentalni pojas
Tiếng Việt: Thềm lục địa
West-Vlams: Continentoal plat
吴语: 大陆架
中文: 大陆架