Inside the Earth

Composition (What it is made of) Crust Mantle Core

The Crust Outer layer 5-100 km thick 2 types of crust Oceanic (very dense, made of basalt) Continental (less dense, made of granite)

Oceanic and Continental Crust

Layers of Earth Crust Basalt: Ocean crust made of dark dense rock and is very thin Granite: Continental crust that is less dense but is thicker (especially where mountains are present) Oceanic Crust Continental Crust 2-3 miles thick Basalt More dense 20-35 miles thick Granite Less dense

The Mantle Middle layer Very thick layer 3,000 km thick

Layers of Earth Mantle Lithosphere: upper most part of the mantle and lower part of the crust About 100 kilometers thick Solid and broken up into plates by cracks Lithosphere

Layers of Earth Mantle The temperature and pressure in the mantle increases with depth The increasing pressure and high temperature cause the lower part of the mantle (asthenosphere) to be soft and gives it the ability to flow easily (plasticity)

Layers of Earth Mantle Asthenosphere: Lower, plasticity part of the mantle that flows easily The core heats this section of the earth, and causes convection current to flow here Asthenosphere

The Core Made mostly of iron 1/3 of the earth’s mass Very hot

Earth’s Layers How are the earth’s layers similar to an egg? Shell=crust Egg white=mantle Yolk=core

Layers of Earth Core Outer core: thick liquid, molten material Inner core: dense ball of solid metal (iron and nickel)

Physical Structure of the Earth (5 Layers) Lithosphere- rigid outer layer (crust) Asthenosphere- solid rock that flows slowly (like hot asphalt) Mesosphere- middle layer Outer Core- liquid layer Inner Core- solid, very dense

Tectonic Plates Earth’s crust is broken into about 19 pieces These plates move on top of the asthenosphere