1. Relative and Absolute Dating
Dating Techniques
Relative and Absolute Dating

2. I. Relative Dating
Principle of superposition-The stuff on the bottom is usually older than the stuff on top.
Unconformities
1. Angular
2. Disconformity
3. Noncomformity
Index Fossils-If we know the age of the sediment or the actual organism, we can

3. II. Absolute Dating
The technique used to determine the age, in years, of an object
Radioactive Decay
1. When the number of neutrons in an atom changes
2. It takes carbon about 5700 y to decay half-way
y = Half-Life of carbon

4. Radiometric Dating
1. The process by which we use the known half-life of a substance to predict how old it is
ex. Potassium-Argon
Uranium-Lead
Uniformitarianism
1. The Earth’s processes occur pretty much the same way they did in the past.