Let’s look at the Earth
The Inside of the Earth is made of Several Layers
The Inside of the Earth is made of Several Layers The Crust: A Thin Rock Material
The Inside of the Earth is made of Several Layers The Mantle: A Dense and Mostly Solid Rock Material
The Inside of the Earth is made of Several Layers The Outer Core: Liquid Iron and Nickel
The Inside of the Earth is made of Several Layers The Inner Core: Solid Iron and Nickel
How Do We Know This? The Crust: The Mantle: The Outer Core: A Thin Rock Material The Mantle: A Dense and Mostly Solid Rock Material The Outer Core: Liquid Iron and Nickel The Inner Core: Solid Iron and Nickel
Why do the layers of the earth float on one another? Density!!!!!
Density determines a layer’s location! Why does any layer float? Why does any layer sink? It is less dense than the one under it! It is more dense than the one above it!
Density
The Density of Earth is 5.53 gm/cm3
The Density of Earth is 5.53 gm/cm3 We know the surface of the Earth is covered with Rocks
The Density of Earth is 5.53 gm/cm3 The Land is covered mostly by a type of rock called Granite (density of Granite = 2.6 gm/cm3)
The Density of Earth is 5.53 gm/cm3 The Land is covered mostly by a type of rock called Granite (density of Granite = 2.6 gm/cm3) The Ocean is mostly covered by a type of rock called Basalt (density of Granite = 3.3 gm/cm3)
The Density of Earth is 5.53 gm/cm3 Granite = 2.7 gm/cm3 Basalt = 3.3 gm/cm3 Neither of these Rocks is dense enough to account for the density of the Earth
The Density of Earth is 5.53 gm/cm3 Granite = 2.7 gm/cm3 Basalt = 3.3 gm/cm3 Iron has a density of 7.9 gm/cm3
The Density of Earth is 5.53 gm/cm3 Granite = 2.7 gm/cm3 Basalt = 3.3 gm/cm3 Iron has a density of 7.9 gm/cm3 So we believe the inside of the Earth is made of a heavy element such as Iron or Nickel (density of Nickel = 8.9 gm/cm3)
The Density of Earth is 5.53 gm/cm3 Density of Rocks 3 gm/cm3
The Density of Earth is 5.53 gm/cm3 Density of Rocks 3 gm/cm3 Density of Iron/Nickel 8 gm/cm3
Earth's Interior Structure Average density Crust Mantle Core 5.5 g/cm3 3 g/cm3 5 g/cm3 11 g/cm3
Density increases with depth ! Earth must have been molten once, allowing denser material to sink, as it started to cool and solidify.
The Density of Earth is 5.53 gm/cm3 Density of Rocks 3 gm/cm3 Density of Iron/Nickel 8 gm/cm3 So we believe about ½ the Earth is a Rock-like material and the other ½ a heavy metal such as iron and nickel The density of the Earth will be the average of the two: