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Maps

Our programs produce accurate geologic maps and 3-D geologic frameworks that provide critical data for sustaining and improving the quality of life and economic vitality of the Nation. They also organize, maintain, and publish the geospatial baseline of the Nation's topography, natural landscape, built environment and more.

Geologic Maps

Geologic Maps

Map Releases

Map Releases

Topo Maps

Topo Maps

Volcanic Maps

Volcanic Maps

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Bedrock topography of south-central Iowa Bedrock topography of south-central Iowa

The bedrock surface in Iowa is covered nearly everywhere by unconsolidated deposits of glacial drift and alluvium which range in thickness from less than 1 foot to more than 400 feet, and from less than 1 foot to about 60 feet, respectively. The bedrock surface is the result of a complex system of ancient drainage courses, which were developed during the long period of preglacial erosion...

Bedrock topography of southeast Iowa Bedrock topography of southeast Iowa

The bedrock in Iowa is covered nearly everywhere by unconsolidated deposits of glacial drift and alluvium, which range in thickness from less than 1 foot to more than 400 feet, and from less than 1 foot to about 60 feet, respectively. The configuration of the bedrock surface is the result of a complex system of ancient drainage courses which were developed during a long period of...
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