accretionary wedge

British

noun

geology a body of deformed sediments, wedge-shaped in two dimensions or prism-shaped in three dimensions, that has been scraped off the surface of the oceanic lithosphere as it moves downwards beneath a continent or island arc. The sediments are added to the continental edge

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Example Sentences

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This feature is called the accretionary wedge, mélange, or accretionary prism.

From Textbooks • Jan. 1, 2017

The accretionary wedge and the forearc sediments were thrust northward onto Tibet.

From Scientific American • Apr. 27, 2015

Sediments and oceanic crust scraped off the descending plate piled up in an accretionary wedge, which created a forearc basin that trapped sediments eroded from Tibet.

From Scientific American • Apr. 27, 2015

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