Skip to main content
U.S. flag

An official website of the United States government

GIS Data

USGS is a primary source of geographic information system (GIS) data. Our data and information is presented in spatial and geographic formats, including The National Map, Earth Explorer, GloVIS, LandsatLook, and much more. Explore GIS Data Maps. 

Filter Total Items: 9586

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...
Was this page helpful?