abstract: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.