1. Earth’s Moving Plates
Mr. Perez

2. Important Vocabulary Density Mesosphere Earthquake Plate Inner core
Outer core
Mantle
Crust
Lithosphere
Asthenosphere

3. Clues to Earth’s Interior
Geologists learn about the interior of our Earth by gathering…
Indirect evidence from SEISMIC WAVES
Waves travel faster through solid rock than liquid rock
By sending seismic waves through Earth, scientists measure their speed and note differences in their path
Earthquake: sudden release in Earth’s crust, causing Earth to shake
Direct evidence from ROCKS
Found in different places on Earth’s surface and made of different materials
Rocks formed deep in the Earth are pushed up to the surface

4. Clues to Earth’s Interior
The seismic clues and rock clues suggest that Earth is made up of layers of different kinds of materials.

6. Earth’s Layers The Earth consists of 4 main layers: Inner core
Outer core
Mantle
Crust

7. Set up your notes like this:
NAME OF LAYER:
Definition
Temperature
Composition
Thickness
Fact(s)

8. Inner core Inner core: innermost layer of Earth (SOLID)
Temperature: up to 9,000°F (hottest layer of Earth)
Composition: Dense layer composed of mostly solid iron
Thickness: about 1,250 km
Fact: Under the greatest amount of pressure (force pushing on an area)

9. Outer core Outer core: layer of Earth that lies above the inner core
Temperature: 4, ,000°F
Composition: Composed of molten (liquid) metal
Stops one type of seismic wave and speeds up the other
Thickness: about 2,220 km
Fact: This layer is responsible for creating Earth’s magnetic field

10. Earth’s Magnetic Field

11. Mantle Mantle: largest layer of the Earth Temperature: 1,600 - 4,000°F
Composition: Composed of solid rock that flows like putty; iron, magnesium, aluminum, silicon and oxygen
Thickness: about 2,900 km
Fact: Contains convection currents that move magma below the Earth

12. Crust Crust: Earth’s outermost layer Temperature: up to 1,600°F
Composition: Composed of solid rock; calcium, sodium and aluminum
Thickness: about 0 – 100 km
Thinnest under the ocean (oceanic crust): 0-5 km
Thickest under the continents (continental crust) 0-30 km
Fact: All of Earth’s surface features are part of the crust

13. Crust
Oceanic crust is made of basalt, a dark colored rock with fine grains
Continental crust is made of granite, a light colored rock with coarse grains

14. Earth’s Structures
Although the Earth’s structure can be divided into 4 basic layers, they can be also divided by physical properties that change with depth below the Earth’s surface
The deeper you go into the Earth, the following increase:
Density
Temperature
Pressure

15. Earth’s Plates
Even though the crust is different from the mantle, the uppermost part of the mantle moves like the crust.
Lithosphere: rigid, upper part of the mantle and crust
Asthenosphere: plastic-like layer below the lithosphere in the mantle
Mesosphere: lower layer of the mantle that borders the liquid outer core

16. Mantle Divisions

17. Earth’s Plates Plates: sections of the Earth’s lithosphere and crust
Move very slowly on the asthenosphere.
Lasers and satellites can measure how far the plates move
The earth is broken up into about 30 different plates.

19. Links

20. Sources
Florida Science Grade 6, Glencoe Science & McGraw Hill Publishing
Google image search