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Leaf Impressions (a model for carbonization)

Stephen F. Greb
Kentucky Geological Survey


Living organisms (including you and me) are composed of the elements carbon, hydrogen, and oxygen. Carbonization is when living tissue leave a carbon film in sediment and rock. Many plant fossils are preserved through carbonization. Soft parts of animals including skin and fur have also been preserved as fossils through the process of carbonization. To illustrate how carbonization works, students will make leaf impressions on paper. This is the old leaf press activity, but instead of being used to preserve leaves, the activity is used to demonstrate the staining as a model for carbonization. You can see examples of fossil impressions on-line at the Kentucky Geological Survey's pictures of different fossil types.

Grade Level : K-8

Time : 15-30 minutes in class or at home and then a week or more to make an impression.

Materials :