Layers of the Earth

There are many layers that make up the earth. From the inner core, deep in the center of the earth, outward to the surface and then layers of the atmosphere until you reach outer space. 

A Sphere is a ball. The atmosphere sphere are gas layers, each has a different density and gas makeup, and also difference changes in temperature with altitude.  Earth layers are solid or liquid, each with a different density and chemical makeup.

Density is the key. Density is the amount of mass, matter, that is packed into an amount of space.  Density = Mass/Volume   Higher density means more matter packed into space.  Like 6 textbooks packed in one backpack is very dense and heavy, 2 textbooks in one backpack is light, less dense.  More dense sinks and is at the bottom and less dense floats or rises up.


earth layers
Atmosphere Layers

  • Four basic layers.  Troposphere, Stratosphere, Mesosphere, and Thermosphere
    The Thermosphere is subdivided to include the ionosphere and the outer most layer that is “Exiting” into space, the Exosphere

Earth Layers

  • Four basic layers. Inner Core, Outer Core, Mantle, and Crust
    • The Inner Core is iron and nickel, while it is the hottest layer the pressure causes it to be solid.
    • The Outer Core is also iron and nickel, it is liquid due to the heat. The rotation, movement of the liquid iron outer core flowing around the solid iron inner core produces Earth’s Magnetic Field.
    • The Mantle is subdivided into the Lower Mantle called the Athenosphere, which is made of a think slow-moving material referred to as being ‘plastic’. It flows in convection currents caused by heat that makes the material rise, then cools and sinks.
    • The upper part of the Mantle is solid and combines with the Crust to make the Lithosphere. Litho means “stone” and the Lithosphere is the solid rocky solid outside layer of the earth. The convection currents from the Asthenosphere has broken the solid Lithosphere layer into sections called tectonic plates that move around.
    • The Crust is the layer that makes the outer most part of the earth, the part live on. The ocean crust is made of dense heavy basalt rock that has sunk deep and low. The Continental crust is made of lighter low-density granite rock that floats around on top.


Earth interior layers

Composition of the Atmosphere

Composition of the Earth’s layers