Plate Tectonics

Global Distribution of Volcanoes

Global Distribution of Earthquakes

Tectonic Plates > Plate Boundaries

If we can provide proof that
Pangaea existed – what else can
we prove?

The Future ...

What is the evidence that Pangaea
existed?
1. Geological Evidence
2. Biological Evidence
3. Climate Evidence

1. Geological Evidence

Fit of South America and Africa

The continents of South America and Africa
look like they should fit together like a jig-
saw puzzle.
There are patterns in the structure of the
mountains in North East USA and North West
Europe that would suggest they should join
together.

2. Biological Evidence

Could Mesosaurus have swum from South
America to Africa?
Researchers say no.

The fossils of Mesosaurus has been found in
both South America and Africa.
Looking at the skeleton of Mesosaurus tells
us that it could not have swam from one
continent to the other therefore the
continents, at one time, must have been
closer.

3. Climate Evidence

Coal
Think about the climate in which coal forming
vegetation grows.

Limestone
> Coral

Limestone is found France and the UK > Must have been
located in a warmer region of the world.

So what are the mechanisms that makes this
happen?
Sea Floor Spreading

Plates are like rafts ‘floating’ onto top of the mantle.

We know about the structure of the earth from the study of the
behavior of waves as they pass through the earth.

Exploring the Ocean Floor

Ranges of submarine mountains in the middle of the Atlantic.

The crust gets older with distance from the Mid-Oceanic Ridge.
There are strips of crust that show alternating polarity.

Convection currents.

Convection currents in the mantle.