analyzing rocks and fossils

Uniformitarianism

means that geologic processes occurring today are like those that occurred in the past.

Absolute Age

is the age of something in years.

Relative Age

is somethings age that is determined by the things around it. 

Superposition

is the law that in undisturbed rock layers the youngest rocks are on the top and the oldest are at the bottom.

Original Horizontality 

means that the majority of rock forming materials are deposited in horizontal layers. 

Lateral Continuity

means that layers of  sediment go in all directions when they are deposited. 

Inclusions

The rule of  states that if a rock has pieces of another rock in it the pieces are older than the rock containing them.

Cross Cutting Relationships

According to the principle of if a geological feature cuts across another feature, the feature cutting across is younger. 

Fossils

are the naturally preserved remains of ancient living things.

Mass extinctions

are a time when lots of species become extinct within a relatively small amount of time.