Plate Tectonics

Divergent

Where to plates collies

Convergent boundary

Where two plates separate

Transform boundary

Where two plates are located parallel

The lithosphere

Includes the crust and the brittle upper most part of mantle

The asthenosphere

Denser ductile semi molten layer that can flow slowly allowing plates to move or float on top

Ductile

Can be stretched or Or pulled without breaking

Moho line

Boundary between the crust and the mantle

What the the mantle composed of?

It is composed of mainly rocks rich and magnesium and iron

What does the upper mantle consist of?

consist of mainly rocks but some areas are partially molten

The lower mantle

It is hotter and denser than the upper mantle

Outer core

The outer core is a liquid layer composed mostly of iron and nickel

The inner core

At the centre of the planet is the inner core

Continental drift theory

The theory that Earth’s continents were once joined together and have slowly moved apart over millions of years.

Mantle convection

The movement of hot and cold material in the Earth’s mantle, which helps move tectonic plates.

Who proposed the mantle convection?

Auther holmes

Seafloor spreading

The process where new oceanic crust forms at mid-ocean ridges and moves away from them.

Plate deformation

The banding breaking or warping of tectonic plates under stress

What does compression lead to?

Folding

What does tension lead to?

Stretching and thinning

What does shearing lead to?

Faulting

Ridge push

Gravity causes the higher oceanic crust at a mid-ocean ridge to slide down and push the tectonic plate away.

Slap pull

oceanic plate sinks into the mantle at a subduction zone, pulling the rest of the plate along with it.

Constructive plate boundary

Were two tectonic plates are moving away from each other

Continental rift zone

An area where a continent is being pulled apart, causing the crust to thin and crack.

Crustal thinning

The process where the Earth’s crust becomes thinner as tectonic plates are pulled apart.

Magma intrusion

• When magma pushes into cracks or spaces within the Earth’s crust.

Mid ocean ridges

An underwater mountain range where new oceanic crust is formed