earths layers

Download Earths  Layers

Post on 10-May-2015

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  • 1.Earth Layers
    • The Earth is divided into four main layers.
    • *Inner Core
    • *Outer Core
    • *Mantle
    • *Crust

2. The Earths Crust

  • The crust is the thinnest layer on Earth, 5 km to 100 km
  • There are two types of crust
      • Oceanic crust made mostly of the igneous rock basalt.Found under the ocean.Relatively thin,
      • 5 kmto 7 km. Contains more iron than the Continental crust, therefore is more dense.
      • Continental crust made mostly of granite.Found under the continents.Relatively thick, up to 100 km.

3. Special parts of the Crust

  • Lithosphere
    • Crust is the upper part of the lithosphere.
    • Broken up into large plates.
    • The uppermost part of the mantle is also part of the Lithosphere
  • Asthenosphere
    • Upper part of mantle, below lithosphere
    • 130 160 km thick
    • Cooler part of the mantle that the lithosphere plates slide on top of.

4. 5. 6. The Earths Mantle

  • Located directly above the outer core
  • Starts below the crust
  • Is the largest layer
  • 80% of the Earths volume & 68% of Earths mass

7. The Earths Mantle

  • Composed of more iron than the crust.
  • Density, pressure, and temperature all increase the deeper you go in the mantle
  • Temperature ranges from 870 C 2200 C

8. 9. Special layers of the mantle

  • Lithosphere crust plus the upper, solid part of the mantle.Forms plates.
  • Asthenosphere just under the lithosphere.Slow moving Silly putty layer on which the lithospheric plates slide.(Solid rock that flows very slowly.)

10. 11. The Earths Core

  • The Earths Core
  • Composed of theinnerandoutercore
  • Both are made of iron and nickel

12. The Earths Outer Core

  • The Outer Core -Liquid
  • Surrounds the inner core
  • Temperature ranges from 2200 C 5000 C near inner core
  • Molten (liquid) iron and nickel

13. 14. The Earths Inner Core

  • The Inner Core - Solid
  • Temperature reaches 5000 C
  • Solid iron and nickel
    • Usually both would be liquid but are solid in the core because of the incredible pressure
  • The solid core is the source of Earths magnetic field

15. Magnetosphere

  • The inner core and outer cores do not turn at the same speed as the rest of the earth.
  • Causes a generator effect which produces a magnetic field.
  • It protects us from some of the suns harmful radiation.

16. 17.

  • What does the inside of the Earth look like?
  • How do scientists know that there is a solid inner core?

18.

  • Determining the composition of the Earth
  • Scientists cannot see the interior of the planet, or drill to the core, so they useseismic wavesto determine the composition of the layers.
  • Seismic waves: are vibrations that are produced when an earthquake happens.
  • Seismic waves travel at different speed depending on the composition and density of material. Measuring these waves tellsus what is in the Earths layers, and how the materials change.

19. i 20. What do you know about these layers?