The Beginning: A trip through Geologic Time Historical info: Catastrophism: Modern Geology: James Hutton: Founded the idea of

Huh? What’s It’s simple: Uniformitarianism means that change occurs over So how do we know what happened when? A method used to place rocks (and events) in__________________

Principles to follow: 1. Law of _______________________ 2. Principle of ________________________ 3. Principle of ___________________ 4. Inclusions 5. Unconformities (_________________________)

Relative age: Absolute age: Unconformity: Fault: Intrusion: Extrusion: Index fossil:

Using relative dating (and other techniques) we can match (CORRELATE) rock layers around the world.

FOSSILS – 7 types Jurassic Park 1 Jurassic Park 2

What conditions help create fossils in rock layers? 1. Rapid _____________ 2. Animal had __________________ – hard stuff that would stay around after being buried The fact that fossils can be used leads to a new law: Law of Fossil Succession: The kinds of animals and plants found as fossils change through time. When we find the same kinds of fossils in rocks from different places, we know that the rocks are the same age.

Let’s review the ATOM: MAKE SURE YOU KNOW THESE PARTS and CAN LABEL THEM!

Interactive Periodic Table Inside each square of the periodic table is ___________________about the element

What does the periodic table have to do with dating rocks and fossils? Some elements have _________: ______________of the element found in nature As time passes, these isotopes break down or ______________

As the rock or dead animal lies on earth, radioactive elements inside it decay Each isotope decays at a different rate. The time it takes for ½ of the atoms in the isotope to decay is called HALF-LIFE Measuring the amounts of each isotope left in the fossil will give us an accurate age Radioactivity in rocks (explained)

Carbon 14 – half life of 5,730 years Uranium 235 – half life of 700 million years