The Restless Earth :: Plate Tectonics

Inside out:

- Inner Core:

Solid, Very Hot (up to 5500 degrees celcius)

- Outer Core

Liquid Iron and Nickle

- Mantle

Upper Mantle Is Hard But Below Is Soft Molten Rock

- Crust

Solid.

Oceanic Plates:

- Underneath the oceans.

- 5-10km thick.

- Denser (3g/cm3) than Continental.

- Younger (>20million) compared.

- Mainly Basalt - Dark, Fine, Gritty - Grains Are So

- Formed From Liquid Lava, Cools Quickly.

Continental Plates:

- 25-100km thick.

- Less Dense (2.7g/cm3) Than Oceanic.

- Older Than Oceanic, (<3.8billion).

- Mainly Igneous Rock / 2 Layers.

- Upper Part, Mainly Granite - Lightly Coloured Course-Grain Magma

- Lower Part Is Basalt & Diorite