Earth

1
Earths Interior

• Essential Question
• How are the Earths layers divided?

2
Earths Interior Vocabulary

• Crust
• Mantle
• Lithosphere
• Athenosphere
• Mesosphere
• Outer core
• Inner core -

3
Who Studies the Earths Structure?

• Geology is the study of the solid Earth.
• Geologists study the forces that have shaped the
  Earth throughout its long history.

4
How Do Scientists Know Whats Inside Earth?

• Because of the extreme conditions in the Earths
  interior, geologists cannot explore deep into the
  Earth.
• Instead they use seismic waves from earthquakes
  to study how they travel through the Earth.
• The speed of seismic waves and the paths they
  take reveal how the planet is put together.
• Geologists have found that the Earths interior
  is made up of several layers.

5
So How Many Layers Are There?

• If you were to travel into the Earth, you would
  find 3 main layers each with its own conditions
  and materials.
• Crust
• Mantle
• Core
• The deeper into the Earth layers you travel, the
  greater the temperatures and pressure.

6
Layers Diagram
7
Earths Crust

• The crust is the outermost layer of the Earths
  surface.
• The crust is composed of rocks, mountains, soil
  and water.
• The crust is the thinnest layer of all of Earths
  layers.
• There are 2 types of crust
• Continental crust that forms the continents made
  of less dense rocks like granite.
• Oceanic crust that is beneath the ocean and made
  of dense rock like basalt

8
Diagram of Earths Crust
9
Earths Mantle

• Between 5 and 40 kilometers deep, a new layer of
  hot rock is found called the mantle.
• This solid material upper layer of the mantle and
  the crust form a rigid layer called the
  lithosphere (100 km thick)
• Beneath the upper layer of the mantle is a
  softer, pliable layer of hot rock called the
  athenosphere.
• The lithosphere floats very slowly on top of
  the athenosphere.
• Beneath the athenosphere, is another 2900 km of
  solid mantle material.

10
Diagram of Earths Mantle
11
Earths Core

• The center layer of the Earth is called the core
  made of nickel and iron.
• The core consists of 2 parts
• Outer core the layer of molten metal that
  surrounds the inner core.
• Inner core the dense ball of solid metal due to
  the extreme pressure there.
• The core makes up 1/3 of the Earths mass, but
  only 15 of its volume.
• The whole core is a little bit smaller than our
  moon.

12
Earths Core Diagram
13
Lets Review

• What is the study of the solid Earth called?
• Scientist who study the forces that have formed
  the Earths surface are called what?
• What 2 things increase the deeper within the
  Earths layers one may go?
• How many layers does the Earth have?
• What are the 2 sublayers with the Earths
  interior?
• What is the difference between the parts of the
  core? Why?