Imprint fossils are also known as impression fossils. They do not contain any carbon material. Imprint fossils include coprolites (fossilized feces), footprints, plants or tracks.
Types of Sediment
Imprint fossils are formed in clay and silt sediment. These sediments are fine-grained and moist and can hold onto an imprint for a long period of time.
Imprint fossils are formed from an organism moving in some way, leaving behind a trace or track. These tracks are preserved when the clay/silt dries slowly and is covered by other sediment. Plants can also leave imprint fossils when they are covered by sediment. The leaf tissue degrades, leaving an imprint of where the leaf once was.
Imprint fossils can give information about an organism's activity and the type of ecosystem that existed where the fossil was found.
Scientists are able to consider how certain organisms moved or interacted with one another, including their gaits and their predator-prey relationships, based on imprint fossils.
Decoding the Fossils
Paleontologists sometimes have a hard time discerning what organism left the imprint fossil, particularly in marine environments where there were many burrowing organisms.