Lake
Paleolakes

Paleolakes are of scientific and economic importance. For example, Quaternary paleolakes in semidesert basins are important for two reasons: they played an extremely significant, if transient, role in shaping the floors and piedmonts of many basins; and their sediments contain enormous quantities of geologic and paleontologic information concerning past environments. In addition, the organic-rich deposits of pre-Quaternary paleolakes are important either for the thick deposits of oil shale and shale gas contained in them, or as source rocks of petroleum and natural gas. Although of significantly less economic importance, strata deposited along the shore of paleolakes sometimes contain coal seams.
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