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.
Answers. Relevance. Rating Newest Oldest. Best Answer: For most types of fossils to form you need sediment (fine particles of rock) to cover the object and harden around it, forming an imprint. Sedimentary rocks are rocks that used to be sediment way back when, so most fossils are found in these types of rocks.Source(s): http://pubs.usgs.gov/gip/fossils/rocks-l...edimentary rocks are rocks that used to be sediment way back when, so most fossils are found in these types of rocks. Source(s): http://pubs.usgs.gov/gip/fossils/rocks-l...