Earth

1
Earths Interior
2
Tell the composition of each of these four layers
of the earth
3

• Crust- continental granite and andesite,
  oceanic basalt

• Mantle- iron, magnesium, silicon, periodite

• Outer core-liquid iron and nickel

• Inner core- solid magnetic iron and nickel

4
What is the consistency of the crust?
5

• Hard and brittle

6
Describe the three parts of the mantle
7

• Lithosphere
• includes the crust and the uppermost mantle
• hard and rigid
• Includes the plates

• Lower mantle
• half of the volume of the Earths interior.
• Very HOT
• Does not flow as well as the athenosphere
• Convection currents help drive the plates

athesnosphere

• Asthenosphere
• (or upper mantle)
• is solid
• very hot
• Plastic, ductile
• like silly putty
• Drives plate techtonics

mantle
lower mantle
8
Describe the layers of the core
9
Outer Coreliquid iron and nickel

• Inner Core
• Solid iron and nickel
• Magnetic
• Spinning faster than the Earth
• About the size of the moon

10
How do scientists know what the Earths interior
is like?
11
By studying seismic waves
12
Describe P Waves
13

• Called primary waves
• Pushing motion
• Very fast
• Travel through gases, solids, and liquids

14
Describe S Waves
15

• Called secondary waves
• Travel slower than P Waves
• Move in a side to side motion
• Can not travel through liquid

16
How has the study of S Waves been particularly
helpful in learning about the interior of the
Earth?
17

• Scientists have observed a S Shadow on the
  opposite of the earth from an earthquake. Since S
  Waves do not travel through liquids, this tells
  us that the outer core is liquid.