Clastic wedge

Clastic wedge

In geology, clastic wedge usually refers to a thick assemblage of sediments--often lens-shaped in profile--eroded and deposited landward of a mountain chain; they begin at the mountain front, thicken considerably landwards of it to a peak depth, and progressively thin with increasing distance inland. Perhaps the best examples of clastic wedges in the United States are the Catskill Delta, and the series of Jurassic and Cretaceous sediments deposited eastward of the Rocky Mountains.[1]

Not all clastic wedges are associated with mountains. They are also characteristic of passive continental margins such as the Gulf Coast; these are quiescent environments, where sediments have accumulated to great thickness over a long period of time.[2] These passive margin continental shelf sediment sequences are termed miogeoclines.[3]

See also

References

  1. ^ Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6 pp. 243, 489
  2. ^ Stanley, p. 516
  3. ^ Dietz, Robert S. and John C. Holden, 1966, Miogeoclines (Miogeosynclines) in Space and Time, Journal of Geology, Vol. 74, No. 5, Part 1 (Sep., 1966), pp. 566-583

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