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(also called deposited rocks) are rocks, which are derived from the decomposition, and weathering of older rocks. The sedimentary rock cover of the continents of the earth's crust is extensive, but the total of that being of is estimated to be only five percent ....

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.... of their mineral layers or beds, which are distinguished from each other by differences in thickness, the size of the grains, or color. All rock disintegrate slowly as a result of mechanical weathering and chemical weathering. Mechanical weathering is the breakdown of rock into particles without producing changes in the chemical composition of the minerals in the rock. Ice is the most important agent of mechanical weathering. Water percolates into cracks and fissures within the rock, freezes, and expands. The force exerted by the expansion is sufficient to widen cracks and break off pieces of rock. Heating and cooling of the rock, and the ....