Clay_qgp

The Clay_qgp file contains information created by and selected from Gran (1997) about the location and shape of industrial clay (see Explanation of the term, Plate IV) mines that are active or inactive. Updated information has been added to this data table in regard to the name of the company that operates the mine, the state of activity, and the reference to the information. The updated information came from personal communication with John Heine, Larry Zanko, and Paul Pojar. The source of this information is:

Gran, S., 1997, Mine Pits in the Minnesota River Valley Corridor; Minnesota Geological Survey [Arcview shapefiles].