General Geology
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General Information
The landscapes in western South Dakota are strongly influenced by erosional activity. Both the northern and southern parts of western South Dakota (geology map) are known as the "Tablelands" because of the prevalence of plateaus and buttes or mesa (also see 3-D topographic map). Rock types which are resistant to weathering cap the butte tops. The landscapes across the midsection of western South Dakota are formed from the more erodible Pierre shale and the landscapes generally have less distinct features.