Illinois State Museum

exhibit panel on the geological record
Click on active areas for closeup and information.

Geologic Record: Rocks Record Changes

Rocks tell a story of environmental change. Changes Institute scientists study the chemical composition and structure of rocks to understand the conditions in which they formed. Many rocks contain fossils of organisms that were alive when the rock formed. The structure, position, and location of rock can reveal clues about glaciers, floods, seismic events, and continental movements. Some rocks can even be dated.