The Earths Structure

Question 1

What are exogenic forces

Answer 1

weathering and erosion is referred to as external/surface forces. These are known as exogenic forces

Question 2

What are endogenic forces

Answer 2

Other processes that shape the earths surface is the movement of the earths plates. These are referred to as internal forces. These are known as endogenic forces.

Question 3

What is the Tectonic Cycle

Answer 3

The tectonic cycle refers to the moving and splitting of the earths crust. These slabs of crust are known as plates.

Question 4

The internal structure of the earth

Answer 4

Inner core: solid, made out of iron and nickel

Outer core: molten/liquid

Mantle: made up of layers of rock, rigid at the uppermost section, gets softer

Asthenosphere: upper layer of the mantle. It is molten and flows like treacle. It is the convection currents in the asthenosphere which cause the plates to move.

Question 5

What is the lithosphere

Answer 5

Lithosphere: outer solid layers of the earth. Continental crust = land, oceanic crust = water, upper rigid layer of the mantle (the moho). It sits on top of the asthenosphere.

Continental crust: 60km thick, made of silica and magnesium, light rocks (sial).

Oceanic crust: 8km thick, made of silica and magnesium, heavy rocks (sima).