County Maps
County mapping is carried out at the ISGS under a variety of programs. The programs exist for different purposes and require different levels of scientific review. Maps are published in specific Series based on the program under which they were created and the corresponding level of review. The links on this page access all downloadable county-scale maps except Coal, Oil, and Gas, which are maintained separately. Please use the Coal Maps and Oil and Gas Maps links to access those maps.
The ISGS Library page provides links to catalogs of ISGS maps and publications.
| Boone, Winnebago | 2000 | Bedrock Geology |
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| Boone | 2000 | Bedrock Topography |
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| Bureau | 2009 | Surficial Geology |
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| Carroll | 1997 | Mineral Resources |
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| Carroll | 1997 | Bedrock Topography |
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| Carroll | 1997 | Data Points |
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| Carroll | 1997 | Surface Slopes |
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| Carroll | 1997 | Land Cover |
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| Carroll | 1997 | Aquifer Sensitivity |
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| Carroll | 1997 | Shaded Relief |
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| Carroll | 1997 | Bedrock Geology |
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| Carroll | 1997 | Surficial GeologyQuaternary Deposits |
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| Carroll | 1997 | Surface Topography |
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| Champaign | 2014 | Surface Topography |
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| Cook | 2004 | Geologic Atlas |
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| DuPage | 2014 | Surface Topography |
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| Hardin | 2014 | Bedrock Geology |
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| Henry | 2011 | Surficial Geology |
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| Henry | 2012 | Surface Topography |
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| Jo Daviess | 2000 | Shaded Relief |
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| Jo Daviess | 2000 | Aquifer Sensitivity |
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| Jo Daviess | 2000 | Land Cover |
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| Jo Daviess | 2000 | Bedrock Topography |
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| Jo Daviess | 2015 | Karst Terrain |
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| Jo Daviess | 2000 | Surficial Geology |
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| Jo Daviess | 2014 | Surface Topography |
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| Jo Daviess | 2000 | Quaternary Deposits |
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| Jo Daviess | 2000 | Bedrock Geology |
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| Jo Daviess | 2000 | Surface Topography |
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| Jo Daviess | 2017 | Karst Terrain |
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| Jo Daviess | 2000 | Data Points |
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| Johnson | 2021 | Bedrock Geology |
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| Kane | 2007 | Bedrock Geology |
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| Kane | 2014 | Surface Topography |
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| Kane | 2013 | Surficial Geology |
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| Kane | 2007 |
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| Kane | 2007 | Aquifer Sensitivity |
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| Kane | 2007 | Cross Sections |
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| Kane | 2007 | Three-dimensional Model |
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| Lake | 2003 | Three-dimensional Model |
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| Lake | 2015 | Surficial Geology |
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| Lake | 2013 | Surface Topography |
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| Lee | 1999 | Quaternary Deposits |
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| Lee | 1999 | Bedrock Geology |
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| Lee | 1999 | Shaded Relief |
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| Lee | 1999 | Data Points |
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| Lee | 2014 | Surface Topography |
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| Lee | 1999 | Bedrock Topography |
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| Lee | 2009 | Outwash Sand Deposits |
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| Lee | 1999 | Surface Topography |
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| Madison | 2006; originally 2006 | Surficial Geology |
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| McHenry | 1995 | Surface Topography |
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| McHenry | 2014 | Surface Topography |
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| McHenry | 2021 | Surficial Geology |
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| McLean | 1998 | Cumulative Sand and Gravel Thickness |
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| McLean | 1997 | Extraction Operations |
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| McLean | 1997 | Drift ThicknessQuaternary Deposits |
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| McLean | 1997 | Data Points |
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| McLean | 1997 | Surface Topography |
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| McLean | 1997 | Bedrock Topography |
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| Monroe | 2012 | Sinkhole Distribution |
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| Monroe | 2021 | Surficial Geology |
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| Monroe | 2014 | Surface Topography |
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| Pope | 2016 | Bedrock Geology |
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| St Clair | 2011; originally 2010 | Surficial Geology |
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| St Clair | 2014 | Surface Topography |
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| Tazewell | 2003 | Data Points |
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| Tazewell | 2003 | Surficial Geology |
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| Tazewell | 2003 | Bedrock Topography |
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| Tazewell | 2003 | Shaded Relief |
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| Tazewell | 2003 | Surface Topography |
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| Tazewell | 2003 | Aquifer Sensitivity |
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| Tazewell | 2003 | Drift ThicknessQuaternary Deposits |
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| Tazewell | 2003 | Extraction Operations |
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| Tazewell | 2003 | Surface Slopes |
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| Union | 2021 | Bedrock Geology |
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| Whiteside | 2014 | Surface Topography |
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| Whiteside | 2013 | Surficial Geology |
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| Will | 2014 | Surface Topography |
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| Williamson | 2020 | Surficial Geology |
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| Williamson | 2020 | Bedrock Geology |
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| Boone, Winnebago | 2000 | Bedrock Geology |
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