The geologic data and maps are produced and distributed by the Minnesota Geological Survey (MGS) as Part A of an Atlas. The Atlas DVD, which is available online at C-43, Geologic Atlas of Cass County, Minnesota, provides all of the maps and GIS data which is free and open to the public.

A County Geologic Atlas (CGA) project is a study of a county's geology, and its mineral and ground-water resources. The information collected during the project is used to develop maps, data-base files, and reports. This same information is also produced as digital files. The map information is formatted as geographic information system (GIS) files with associated data bases. The maps and reports are also reproduced as portable document files (PDFs) that can be opened on virtually any computer using the free Acrobat Reader from Adobe.com. All of the digital files for the CGA's can be downloaded from the University of Minnesota Digital Conservancy. The majority of the files can also be viewed and queried through the use of this Story Map.Atlas information is commonly used in planning and environmental protection programs, as an educational resource, and by industries involved in water and mineral resources. It represents a comprehensive, detailed compilation of geologic data and interpretations within a county. The distribution and character of geologic materials determine how and where water enters the earth, and where it is stored in aquifers that can supply our needs. Geologic maps are a key element in delineating those flow paths and in relating land use to water quality. The atlas also provides a framework and terminology to support more detailed, site-specific studies. The records of water wells drilled in the area are an important source of data for constructing the maps and for understanding the distribution and use of ground water in the county. A data base of the information from those wells is one of the atlas products, and it can be queried with the GIS files to yield valuable insights for managing the ground-water resource.The atlas is also useful to non-professionals who simply wish to learn more about the geology of the county. It is a one-stop, comprehensive collection of information in a variety of forms and styles that should be useful to anyone with an interest in earth science or the county.The geologic data and maps are produced and distributed by the Minnesota Geological Survey (MGS) as Part A of an Atlas. The Minnesota Department of Natural Resources follows with an investigation of the quantity, quality, and pollution sensitivity of ground water. Their products are distributed as Part B of the atlas, at a later date. If necessary, a report with additional information that was not possible to include on the limited space of the printed maps is produced by MGS as Part C of, or included as a supplement to, an atlas. The Atlas CD or DVD, which is available online at the Digital Conservancy, includes all the atlas products developed by the Minnesota Geological Survey.

This map shows the free and open data status of county public geospatial (GIS) data across Minnesota. The accompanying data set can be used to make similar maps using GIS software.

Counties shown in this dataset as having free and open public geospatial data (with or without a policy) are: Aitkin, Anoka, Becker, Beltrami, Benton, Big Stone, Carlton, Carver, Cass, Chippewa, Chisago, Clay, Clearwater, Cook, Crow Wing, Dakota, Douglas, Grant, Hennepin, Hubbard, Isanti, Itasca, Kittson, Koochiching, Lake, Marshall, McLeod, Meeker, Mille Lacs, Mower, Norman, Olmsted, Otter Tail, Polk, Pope, Ramsey, Renville, Rice, Scott, Sherburne, Stearns, Steele, St. Louis, Traverse, Waseca, Washington, Wilkin, Wright and Yellow Medicine.

To see if a county's data is distributed via the Minnesota Geospatial Commons, check the Commons organizations page: https://gisdata.mn.gov/organization

To see if a county distributes data via its website, check the link(s) on the Minnesota County GIS Contacts webpage: https://www.mngeo.state.mn.us/county_contacts.html

This map portrays our current geologic understanding of the temporal and geographic distribution of units within major Precambrian terranes and of the Phanerozoic strata. The state wide data is mapped at a scale of 1:500,000 and the county bedrock datasets (Becker, Brown, Meeker, Isanti, Cass) are mapped at a 1:100,000 scale. A Story Map displaying this data can be found at Minnesota's Bedrock Geology story map.The western part of the mapped Precambrian terrane in the state wide dataset is inferred largely from geophysical maps, anchored locally by drilling. In many places, contacts are drawn between units of the same or similar apparent rock type (and same unit label); these are recognized as geometrically distinct, though geophysically or lithologically similar. Digital files for the state wide bedrock (http://hdl.handle.net/11299/101466) corresponding to this map allow removal of Cretaceous, Paleozoic, and some parts of Mesoproterozoic strata to reveal an interpretation of the underlying Precambrian bedrock.

For additional state wide data see: (http://hdl.handle.net/11299/98043) which contains files associated with Bedrock Topography, Depth to Bedrock, and locations of Outcrop and Geochronologic analyses. Individual county bedrock can be found and downloaded at the University of Minnesota's Digital Conservancy.