1. Evidence of Earth’s History
8.E.2.1 and 8.E.2.2

2. Deposition is the process that A. dissolves sediment
Warm up
Deposition is the process that
A. dissolves sediment
B. breaks down rock
C. drops sediment
D. moves rock particles

3. QUIZ
1. This type of rock has layers.
2. This type of rock forms from magma or lava.
3. This type of rock changes from an existing rock.
4. Igneous rock from _______ has large grains
5. Igneous rock from _______ has small grains.

4. Group Activity

5. Evidence of Earth’s History
Just as earth’s lithosphere has changed over time so has earth’s climate and life forms
Fossils, ice cores and rock provide evidence about changes
Geology is the study of earth’s history

6. Fossils
Fossils- preserved remains or evidence of organisms that once lived
Formed after the organism died and was covered by sediment
If the organism decays it leaves a mold- a hollow space in the rock that shows the shape of the organism
Hard parts( teeth, bones) are preserved
Behaviors or actions can be preserved such as footprints

7. Fossils

8. Ice cores Ice core- a cylinder of ice removed from an ice sheet
Ice builds up in layers like sediment in areas where ice doesn’t melt in the summer
The texture of the snow is different in the winter and summer
Air bubbles in the ice provide evidence about the atmosphere ( dust, ash and carbon dioxide)

9. Rocks
Radioactive dating- measures the age of material by measuring the amount of radioactive material
The decay process happens at predictable rates
For example- uranium decays into lead