Earth's History Vocabulary

A scientist who studies the earth.

Data, or information, that either supports or counters a scientific theory of idea.

The setting of sediments.

A model used to study Earth's history that divides the history into blocks of time.

The number of different species in an area.

The process of determining whether one rock, fossil or event is older.

Era in which dinosaurs were the dominant species:

Layers of rock

Study of fossils

A major division of geological time

An event that results in living things becoming extinct at the same time

The largest division of time

Era in which mammals were the dominant species:

A length of time is required for half of the radioactive atoms in a sample to decay.

Process by which rock, soil, and sand are broken down.

The process of determining the approximate age of a rock

The preserved remains of an organism.

States that in an undisturbed layer of rock, older rocks lie at the bottom.

The era of Earth when fish, amphibians and invertebrates were the dominant species:

A well-tested explanation of scientific observations and experiments