Tracks can be fossilized over millions of years. It is for this reason we are able to see fossilized dinosaur tracks in some types of rock formations. These types of fossils are called trace fossils since they are a trace of an animal left behind rather than the animal itself. In paleontology, tracks often preserve as sandstone infill, forming a natural mold of the track.
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- Vitkus, Allison; Chin, Karen; Lockley, Martin. "Fossil footprints through geologic time". University of California Museum of Paleontology. Retrieved April 7, 2016.
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