Formation of Sedimentary Rock
Sediments form sedimentary rock by compaction and cementation of the particles. Thus, coarse sediments become conglomerates; sands become sandstone; and muds become shale. Sedimentary rocks make up only about 5% of all rocks of the earth's crust, yet they cover 75% of the land area in a veneer that averages 2.26 km (1.4 mi) in thickness, ranging from 0 to 12.9 km (0–8 mi).
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