1. Earth’s Story

2. How is the Earth shaped? Uniformitarianism – the belief that Earth has changed gradually and continuously over time. “the present is the key to the past” Catastrophism – All geologic changes occur suddenly.

3. Which one is true? Modern geologists believe Earth is shaped by both!  Gradual processes such as erosion and weathering  Sudden changes like a meteor impact or a volcanic eruption

4. Relative Dating?? Relative dating – is time in relationship to something else Which came first?? It is like saying I am older than you but you do not know by how much!

5. Relative Dating Activity I stood in the checkout line. I selected two apples. I walked home from the store. I gave the cashier the money. I went to the store. The cashier gave me my change. I was hungry.

6. Hopefully…..  I was hungry.  I went to the store.  I selected two apples.  I stood in the checkout line.  I gave the cashier money.  The cashier gave me my change.  I walked home from the store.

7. Law of Superposition The law states that the younger/newer rocks are on top of or above older rocks.

8. Everyday Examples Pile of laundry. Bricks used to build a house. Your school folder. Stack of magazines.

9. Disturbing Forces! Rock layers can be disturbed by forces from within the Earth.  rocks can intrude  rocks can tilt  rocks can fold  faults form Because of these disturbances the sequence of the layers may be changed.

10. List in order from youngest to oldest.

11. Did you get the correct answer?? Youngest E D A B C Oldest

12. Geologic column A sequences of rock layers that contain all the known fossils and rock formations on Earth arranged from oldest to youngest.