1 Removing heat energy, or cooling, decreases the motion of molecules. 2  If heat is added to a solid, the molecules can move fast enough to change from a solid to a liquid. ( 3 Melting). 4  If heat is added to a liquid, the molecules can move fast enough to change from a liquid to a gas.
Fossils usually only form in sedimentary rock. Sediments have to accumulate over the organism in order to preserve it. This could be a rapid burial, such as a volcanic eruption or mudslide, it could be sap from a tree oozing over an insect, or simply a slow sediment accumulation on the bottom of a lake.
If the magma cools slowly, large crystals form in the rock. This can happen if the magma cools deep underground. Granite and gabbro are examples of this type of rock. They are intrusive igneous rocks because they form from magma underground. Unlike sedimentary rocks, igneous rocks do not contain any fossils.This is because any fossils in the original rock will have melted when the magma formed.1  Page. 2  1. 3  2.ranite and gabbro are examples of this type of rock. They are intrusive igneous rocks because they form from magma underground. Unlike sedimentary rocks, igneous rocks do not contain any fossils. This is because any fossils in the original rock will have melted when the magma formed. 1  Page. 2  1.