Caprock

For the region near Texas, see Caprock, Texas. Caprock is a geological term for a harder or more resistant rock type overlying a weaker or less resistant rock type. Common types of caprock are sandstone and ultramafic rock types. In processes such as scarp retreat, the caprock controls the rate of erosion of the scarp. As the softer rock is cut away, periodically the caprock shears off. Caprock is also found on the top of mesa formations.
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