Bedrock Geology: Illinois, 2005
2005. Illinois State Geological Survey. This feature dataset shows the distribution and extent of the bedrock geologic units within the State of Illinois, as depicted on the map Bedrock G...
Bedrock Geology of Illinois - Geologic Units, 2004
1996. Illinois State Geological Survey. This feature class shows the distribution and extent of the bedrock geologic units within the State of Illinois, as depicted on the Geologic Map of...
Potential of Agricultural Chemical Contamination of Aquifers, 2004: Illinois
1995. Donald A. Keefer, and Illinois State Geological Survey. This is a statewide SDE feature dataset for evaluating the potential for contamination of shallow aquifers by pesticides and nitrate. The sources o...
