Sedimentary rocks are known for their ability to preserve ancient remains of organisms called fossils. This is because they do not form under conditions of high temperature and pressure as igneous and metamorphic rocks form.
For the preservation of fossils, conditions must be very favorable in which the parts of the organism will not be destroyed.
Igneous and metamorphic rocks form under medium to high grade pressure and temperature environment.
Therefore, this will not allow for organic matter from organisms to be preserved.
