You searched for: Publisher Illinois State Geoligical Survey Remove constraint Publisher: Illinois State Geoligical Survey Collection Illinois Geospatial Data Clearinghouse Remove constraint Collection: Illinois Geospatial Data Clearinghouse
2003. Illinois State Geological Survey. This is a statewide ArcSDE Raster Mosaic of USGS DRG images of 7.5-minute topographic quadrangles occurring in Illinois. These are unmodified DRG i...