Measures in Time: Explore the Virtual Museum Further Reading


What is lichenometry?
Lichenometry is a technique that earth scientists use to estimate the age of lichen covered surfaces. This allows them to accurately estimate when landscape changes happened due to such things as glacial advances, earthquakes and floods. Lichenometric ages can be quite accurate and the technique is especially useful in the arctic and alpine tundra where there are no trees.

What are lichens?
Lichens are made up of at least one algae and a fungus. The algae use photosynthesis to make food for the lichen and the fungus shelters the algae in a "greenhouse." After a glacier retreats, lichens are quick to become established. Some lichens grow slowly outward to form circular patches that can live for centuries.


Lichens and Trees Lichen Growth