Relative Dating and the Law of Superposition

Front

What is relative dating?

Back

Relative dating is any method of determining whether something is older or younger than something else.

Front

What does the Law of Superposition state?

Back

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

Front

Which layer is older: layer M or intrusion P?

Back

Layer M is older than intrusion P.

Front

How do fossils help in relative dating?

Back

Fossils can indicate the relative age of rock layers based on the types of organisms that existed at different times.

Front

What is an intrusion in geology?

Back

An intrusion is a body of igneous rock that forms when magma cools and solidifies beneath the Earth's surface.

Front

If a rock layer contains trilobite fossils, is it older or younger than a layer with dinosaur fossils?

Back

The rock layer with trilobite fossils is older than the layer with dinosaur fossils.

Front

What is the significance of the order of rock layers?

Back

The order of rock layers helps geologists determine the relative ages of the rocks and the fossils within them.

Front

What is an example of a method used in relative dating?

Back

One method is to compare the positions of rock layers and the fossils they contain.

Front

What does it mean if a rock layer is described as 'younger'?

Back

It means that the rock layer was formed after the layers below it.

Front

What is the relationship between sedimentary rock layers and fossils?

Back

Sedimentary rock layers often contain fossils that provide clues about the age of the layers.