1. 1) What is uniformitarianism?
The same geologic processes are at work today as those throughout the Earth’s history.
Charles Lyell

2. 2) What is catastrophism?
All geologic change occurs suddenly as the result of catastrophe.

3. 3) What is relative dating?
Determining if an object or event is younger or older than another.

4. 4) What is the Law of Superposition?
The principle that the oldest rock can be found on the bottom.

5. 5) What is a geologic column?
Layers of rock representing the different time periods of the Earth. (Oldest to Youngest)

6. Dating Rocks and Fossils
Key Questions:
What is absolute dating?
 What is Radiometric Dating?
 What is carbon dating?
 What is half-life in radioactive decay?

7. 1) What is absolute dating?
Gives the age of an object in years.

8. 2) What is radiometric dating?
Figuring out the absolute age of a sample by comparing the amount of original material to new material.

9. 3) What is carbon dating?
A type of radiometric dating that measures the decay of carbon.
Animals and plants take in carbon until they die.
The amount of carbon decreases as they decay.
This decrease can be measured in a lab giving an age for a fossil.

11. 4) What is half-life in radioactive decay?
Half-Life is the time it takes for one-half of the carbon to decay.
Half-life of carbon is 5,730 years.
This type of dating works for samples that lived in the last 50,000 years.