Map PDF PDF of Buried Bedrock Surface of Illinois General Information: Description One 33" x 60" map sheet, includes legend, 4 figures, and descriptive text. Publication Details: Publication Date 1994 Authors Beverly L. Herzog Barbara J. Stiff Cheri A. Chenoweth Kelly L. Warner Jennifer B. Sieverling Charles Avery Map Details: Series ID IMAP 5 Theme Bedrock Topography Scale Category Statewide Scale 1:500,000
