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Laryngitis Materials:
All work is due on April 12!
Class Schedule:
- Tues 4/5: class
- Thurs 4/7: no class
The Earth's internal structure
Outline
- Introduction to today's lecture
- How do we know the Earth's age?
- The Earth's internal structure
- Rocks and Minerals
- Three types of rock
- More about igneous rocks
- Powerpoint
lecture notes
- Outline
- Basic Concepts
- Geologic Time1
- Geologic Time2
- An Illustration of Geologic Time
- Geologic Time Simplified -We covered up to this point in class-
- How do we know the Earth's age?
- The Earth's internal structure
- Rocks and Minerals
- Three types of Rock
- Igneous Rock
The Earth's internal structure
The materials of the Earth are organized so that the dense materials are closest to the center, and the least dense materials are at the surface. The Inner Core is at the center, and is made of solid Iron. The Outer Core is made of liquid Iron. Next is the Mantle, which is a plastic solid rich in Iron and Magnesium. Although it is solid, it is a plastic solid, and slowly deforms, perhaps the way Play-Dough or molten glass does. Finally, on the surface, is the Crust, or Lithosphere, which is also solid. There are two types of crust: Oceanic crust, which is thin and made of the same materials as the Mantle: it is rich in Magnesium and Iron. Then there is the Continental crust, which is high in Silica, and tends to be thicker and less dense than the Oceanic crust.
Examine these two cross-sections to get a sense of scale:
Next up: Rocks and Minerals