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CONTINENTAL SHELF
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See also:CONTINENTAL SHELF , the See also:term in See also:physical See also:geography for the submerged See also:platform upon which a See also:continent or See also:island stands in See also:relief. If a See also:coin or See also:medal be partly sunk under See also:water the See also:image and superscription will stand above water and represent a continent with adjacent islands; the sunken See also:part just sub-merged will represent the continental shelf and the edge of the coin the boundary between it and the surrounding deep, called by See also:Professor H. K. H. See also:Wagner the continental slope. If the See also:lithosphere See also:surface be divided into three parts, namely, the continent heights, the ocean depths, and the transitional See also:area separating them, it will be found that this transitional area is almost bisected by the See also:coast-See also:line, that nearly one-See also:half of it (ro,000,000 sq. m.) lies under water less than zoo fathoms deep, and the See also:remainder 12,000,000 sq. m. is under 600 ft. in See also:elevation. .There are thus two continuous See also:plain systems, one above water and one under water, and the second of these is called the continental shelf. It represents the area which would be added to the See also:land surface if the See also:sea See also:fell 600 ft. This shelf varies in width. See also:Round Africa—except to the south—and off the western coasts of See also:America it scarcely exists. It is wide under the See also:British Islands and extends as a continuous platform under the See also:North Sea, down the See also:English Channel to the See also:south of See also:France; it unites See also:Australia to New See also:Guinea .on the north and to See also:Tasmania on the south, connects the See also:Malay See also:Archipelago along the broad shelf See also:east of See also:China with See also:Japan, unites north-western America with See also:Asia, sweeps in a symmetrical See also:curve outwards from north-eastern America towards See also:Greenland, curving downwards outside See also:Newfoundland and holding See also:Hudson See also:Bay in the centre of a shallow dish. In many places it represents the land planed down by See also:wave' See also:action to a plain of marine denudation, where the waves have battered down the cliffs and dragged the material under water. If there were no compensating action in the See also:differential See also:movement of land and sea in the transitional area, the whole of the land would be gradually planed down to a submarine platform, and all the globe would be covered with water. There are, however, periodical warpings of this transitional area by which fresh areas of land are raised above sea-level, and fresh continental coast-lines produced, while the sea tends to sink more deeply into the See also:great ocean basins, so that the continents ' slowly increase in See also:size. "In many cases it is possible that the continental shelf is the end of a See also:low plain submerged by subsidence; in others a low plain may be an upheaved continental shelf, and probably wave action is only one of the factors at See also:work " (H. R. See also: Additional information and CommentsThere are no comments yet for this article.
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