Earth’s Interior and Plate Tectonics

Beginning• The earth began as a

molten ball of liquid rocks and made up of randomly mixed materials.

• Over time the materials separated.

• Dense materials such as nickel and iron sank in the center of the earth and form the core.

Earth’s Interior and Plate Tectonics

Beginning• Less dense

materials rose to the top and form the earth’s crust

Earth’s Interior and Plate Tectonics

Beginning• As it cool it’s

crust, mantel and core developed

Layers of the Earth

Inner Core

• Made up of Nickel and Iron• 1,228 KM thick• Solid due to high pressure

from the weight of the upper layers. The hottest layer.

Outer Core

• Made up of Nickel and Iron• 2,220 KM thick• Liquid. Due to the heat of the

inner core, Iron and Nickel melts and remain liquid.

Mantle

• Varied Minerals• 2,900 KM thick

Lower Mantle called Mesosphere

Middle Mantle called Asthenosphere

Upper Mantle called Lithosphere

Crust• Made up of Rocks/Minerals• 5 - 70 KM thick• Solid. As rocks and minerals

grew cold, they solidify.• Mesosphere is liquid• Asthenosphere is pyro-plastic• Lithosphere is solid

Plate Tectonics

• Plate Tectonics – The theory that earth’s surface is made up of large moving plates

Plate Tectonics

• Lithosphere – the thin outer shell of Earth, consisting of the crust and the rigid upper mantle.

Plate Tectonics

• Athenosphere – The zone of the

mantle beneath the lithosphere

– consists of slowly flowing solid rock.

Plate Tectonics

• Magma – molten rock within the earth.

• Heats up materials causing it to expand

Plate Tectonics• Expanding

region of athenosphere pushes lithosphere upwards.

• This causes the lithosphere to crack.

Two kinds of Plate Movements

• Divergent Movement

• Convergent Movement