Geodatabase of the datasets used to represent the four aquifer subunits of the Cambrian-Ordovician aquifer system, Illinois, Iowa, Michigan, Minnesota, and Wisconsin
This geodatabase includes spatial datasets that represent the Cambrian-Ordovician 
aquifer system in the States of Wisconsin, Michigan, Minnesota, Iowa, and Illinois. 
Included are: 
			(1) a polygon dataset that represents the aquifer system extent, 
			(2) raster datasets for the altitude of each aquifer subunit, …