Absolute Dating vs Relative Dating

Front

What is the Principle of Superposition?

Back

In an undisturbed sequence of rock layers, the oldest layer is at the bottom and the youngest layer is at the top.

Front

What is a half-life?

Back

The time required for half of the parent isotope in a sample to decay into its daughter isotope.

Tags

NGSS.HS-PS1-8

Front

If you start with 1000 parent atoms, how many will remain after 2 half-lives?

Back

250 parent atoms.

Tags

NGSS.HS-PS1-8

Front

What is an index fossil?

Back

A fossil that is used to define and identify a particular time period in the geological time scale.

Tags

NGSS.MS-ESS1-4

Front

What does it mean if two rock layers contain the same index fossil?

Back

It indicates that the rock layers are approximately the same age.

Tags

NGSS.MS-ESS1-4

Front

What is a parent element in radioactive decay?

Back

The original unstable isotope that undergoes decay to form a stable daughter isotope.

Tags

NGSS.HS-PS1-8

Front

What is a daughter element?

Back

The stable isotope that is produced from the decay of a parent element.

Tags

NGSS.HS-PS1-8

Front

What is the significance of the half-life in dating rocks?

Back

It helps determine the age of rocks and fossils by measuring the amount of parent and daughter isotopes present.

Tags

NGSS.HS-PS1-8

Front

If the half-life of a radioactive isotope is 100 years, how old is a rock that has gone through two half-lives?

Back

200 years old.

Tags

NGSS.HS-PS1-8

Front

What is relative dating?

Back

A method of determining the age of rocks and fossils by comparing them to other rocks and fossils.