Understanding Geologic Time Assessment

Front

What is relative age?

Back

Relative age is the age of an object in relation to other objects.

Front

What is absolute age?

Back

The actual age of a geological feature or fossil, measured in years.

Front

What do the divisions of the Geologic Time Scale represent?

Back

The divisions represent major changes in flora (plants) and fauna (animals).

Front

What does the Law of Superposition state?

Back

Newer rock layers form on top of already existing layers; older layers are at the bottom.

Front

Which layer is the oldest in a sequence of rock layers?

Back

The oldest layer is the one at the bottom of the sequence.

Front

What is the Law of Inclusion?

Back

Fragments of rock found within another rock are older than the rock that contains them.

Front

What does the Law of Crosscutting state?

Back

Any feature that cuts across a sequence of rocks is younger than everything it cuts.

Front

What are index fossils?

Back

Fossils that show up in abundance in the same layer of Earth across many different regions.

Front

How do scientists use index fossils?

Back

Scientists use index fossils to conclude that the age of each 'strata' or layer is similar.

Front

What is the significance of the Geologic Time Scale?

Back

It helps to understand the history of Earth and the evolution of life over time.