While maps provide a location in space, geologists must also locate their study sites and specimens with respect to relative geologic time. This is commonly done by identifying the geologic formation that is represented at a particular site, based on previous work in the region.

In the case of Lime Kiln Park, outcrops at the study quarry are part of the Racine Formation. Work by several generations of geologists in southeastern Wisconsin has demonstrated that the Racine Formation overlies (is younger than) the Waukesha Formation and underlies (is older than) the Waubakee Formation. Previous work has also shown that the fossil content of the Racine Formation indicates a Silurian age.

© 1997, Milwaukee Public Museum, Inc.