Take a look at the following pictures and infer what they all have in common. What is the common link?

Brain Storm How do you know there are different layers? Use at least 3 ways you could describe the layers to someone else. What kinds of things can you say about what the layers are made of?

Watch the following video facts-composition-temperature.html facts-composition-temperature.html

Clues to Earth’s Interior Deep mines Deep wells Samples and Observations

What changes occur as you move toward the center of the Earth? Temperature and pressure increase

Using Earthquake Waves Scientists study earthquake waves and how they move through the different layers Some waves stop Some waves change direction Scientists guess (infer) density and composition of layers

Density Thickness Compact How close together something is packed Ex: suitcase, backpack (empty vs. full)

Crust Rocky outer layer Thinnest Least dense Silicon and oxygen Crust under ocean=oceanic crust Crust under land=continental crust Ocean crust is denser than continental crust

NOTE How does oceanic crust differ from continental crust?

Mantle Under the crust Very thick middle layer Contains more iron and magnesium 3 parts Lithosphere Asthenosphere Mesosphere

LITHOSPHERE Made of the crust and the rigid upper mantle. Lithos – means stone/rock Divided into pieces called tectonic plates.

ASTHENOSPHERE Plastic-like Hot & it flows Lithosphere slides on top of asthenosphere Asthenes means weak

NOTE Compare the lithosphere and the asthenosphere

MESOSPHERE Strong lower part of the mantle Meso – means middle.

Core Center of Earth 2 parts 1- Liquid–OUTER CORE 2-Solid – INNER CORE

NOTE What are the interior layers of Earth?

Outer Core Hot liquid made of iron and nickel Movement produces the Earth’s magnetic field.

NOTE What evidence indicates that the outer core is liquid?

Inner Core Very hot pressed into solid metal ball due to extreme pressure. Mostly made of iron Inner core spins faster than the rest of Earth.

Earth’s Magnetic Field Inner core spins faster than outer core Produces streams of molten iron in the outer core This produces a magnetic field around Earth Field can change direction

Magnetosphere Outer part of magnetic field that interacts with particles from the sun Magnetic field protects Earth from Cosmic Rays from sun Charged particles from sun

NOTE How is Earth’s magnetic field formed and how does the magnetosphere protect Earth.