Relative and Absolute Dating

Front

What is Absolute Age?

Back

The actual age in years of an event or object.

Front

What is Relative Age?

Back

The age of geologic features compared with things nearby.

Front

What does it mean if a rock layer is relatively younger than another?

Back

It means that the younger layer was deposited after the older layer.

Front

What are Index Fossils?

Back

Fossils that are used to define and identify a particular time period in the geologic time scale.

Front

What criteria must Index Fossils meet?

Back

They must have existed for a short period of time and be widely distributed.

Front

Which rock layer most likely contains fossils of the oldest organisms?

Back

The lowest layer in a sequence of sedimentary rocks.

Front

What is the Law of Superposition?

Back

In undisturbed sedimentary rock layers, the oldest layers are at the bottom and the youngest are at the top.

Front

How can fossils help determine the relative age of rock layers?

Back

Fossils found in different layers can indicate the order of deposition and the relative ages of the layers.

Front

What is a Geologic Time Scale?

Back

A system of chronological dating that relates geological strata to time.

Front

What is the significance of sedimentary rock layers?

Back

They provide a record of Earth's history and the life forms that existed at different times.