1. Structure & Composition of the Earth
4.a. Compare & contrast the lithosphere & the asthenosphere. (DOK 1)
Composition, density, & location of continental crust & oceanic crust
Physical nature of the lithosphere with the asthenosphere
How the lithosphere responds to tectonic forces

2. Bellwork 1/26
Sean is studying the advantages of selective breeding in plants. He made the following list of possible advantages: 1) Can produce corn that attracts grasshoppers 2) Can develop grass that can grow with less water 3) Can develop wheat that can grow in different types of soil 4) Can produce oranges that are not affected by freezing temperatures Which items on the list provide logical arguments in favor of selective breeding? A. 1, 2, 3 B. 2, 3, 4 C. 2, 4 D. 3, 4

3. The layers of the earth
Order of the Earth’s interior from the surface to the center:
Crust
Mantle
Outer core
Inner core

4. The crust This is the layer you live on
The crust is the most widely studied & understood layer of the Earth
Like the skin of an apple

5. The crust Very thin in comparison to the other 3 layers of the Earth
3-5 miles thick under the ocean
Oceanic crust
Thinnest part of the crust is under the ocean
About 25 miles thick under the continents
Continental crust
Thickest part of the crust is under mountain ranges

6. The crust Broken into many pieces called plates
The plates “float” on the soft, plastic mantle that is very hot!
Temperatures range from atmospheric temperature near the surface to 1600 degrees Fahrenheit near the mantle
Thinnest layer of the Earth

7. The crust Composed to 2 basic rock types: Basalt Granite
Volcanic lava rock
Oceanic crust
Granite
Continental crust
Basalt rock is much denser & heavier than granite

8. The lithosphere Located in the crust & the upper layer of the mantle
Rigid & brittle rock

9. The asthenosphere Just below the lithosphere
Located in the upper part of the mantle
Plastic & flowing
Moves the plates of the Earth

10. The mantle Located under the crust Largest layer 1800 miles thick
Very hot & dense rock
Contains the asthenosphere & part of the lithosphere

11. The mantle Layers of rock flow like asphalt under a heavy weight
Due to the great temperature differences from the bottom to the top of the mantle
Movement of the mantle is the reason the plates of the Earth move
The Asthenosphere
Temperature near the top of the mantle: 1600°F
Temperature near the bottom of the mantle: 4000°F

12. The outer core Temperatures starting at 4000°F
So hot that the metals in it are all in the liquid state
Located 1800 miles beneath the crust
1400 miles thick
Composed of 2 metals:
Nickel
Iron

13. The inner core
Temperatures & pressures are so great that the metals are squeezed together and are not able to move about like a liquid
Forced to vibrate in place as a solid
Begins about 4000 miles beneath the crust
800 miles thick
Temperatures reach 9000°F
Pressures are 45 million pounds per square inch
This is 3 million times the air pressure at sea level

14. Facts about the inner & outer core
The inner core -- combined with the outer core -- provide the magnetic field that surrounds the earth.
The spin of the earth causes a rotation of the inner core.
The spin of the liquid outer core around the mostly-iron inner core creates the magnetic field.

15. Earth’s formation & composition
Many geologist believe that as the Earth cooled, the heavier, denser materials sank to the center and the lighter materials rose to the top
Scientists are concerned that the increasing levels of CO2 in the atmosphere could cause overall heating of the Earth’s interior
Geologists drill through the oceanic crust in their attempt to reach the mantle because it is thinner than the continental crust

16. Earth’s formation & composition
As Earth’s depth increases, the density, temperature & pressure also increases

17. Deformation of earth’s crust
Earth’s crust can be deformed through:
Faulting – a break or crack along which rocks move
Folding – a bend in a rock
Folding
Faulting

18. Write down these questions….
Describe the outer core.
What layer of the Earth is the thickest?
What layer of the Earth is the thinnest?
What part of the crust is the thickest?
What part of the crust is the thinnest?
What part of the Earth is classified as plastic and flowing?
What is faulting?
What is folding?
What state is the inner core in?
What layer of the Earth is like the skin of an apple?
What are the 4 layers of the Earth?
What 2 types of rock is the crust composed of?
Which type of rock is found in the continental crust?
Which type of rock is found in the oceanic crust?
What part of the Earth is classified as rigid and brittle?
How thick is the mantle?
What are the 2 parts of the core?
What temperature does the inner core reach?
What factors increase as the Earth’s depth increases?
What are the two ways the Earth’s crust can become deformed?

19. Bellwork 1/27
Tinea pedis is a disease caused by a fungus. It affects mainly external body parts and not internal systems. Which of these could be a symptom of tinea pedis? F. Difficulty breathing G. Pain in the intestines H. Headaches and dizziness J. Swollen and itching skin

20. Classwork Complete Layers of the Earth worksheet packet.
If you finish before the bell rings, you may read a book or work on something from another class.

21. Bellwork 1/28
List the layers of the Earth in order from the surface to the interior.
Study your notes!