Gneous rocks are made mainly of compounds of: carbon and hydrogen silicon and oxygen carbon and silicon carbon and oxygen

Fossilization - The preservation of an ancient artifact.
Index Fossil - A fossil that is useful for dating and correlating the strata in which it is found.
Faunal Succession - The observation that a sedimentary rock strata contains fossilized flora and flauna.
Tar - A dark, thick liquid distilled from wood or coal.
Ice - Frozen water.
Evolution - The process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth.
Variation - The difference between cells, individual organisms, or groups of organisms of any species.