earths structure

Let the Fun Begin!

Earth’s Structure

What would it look like to you!?!?!

Plate Tectonics

A short video Cliphttp://

www.youtube.com/watch?v=ryrXAGY1dmE&feature=related

4 Main Layers

How do we know what it looks like?

Geologist record the seismic waves that earthquakes make and study how they travel through Earth.

The speed of these seismic waves and the path they take reveals how the planet is put together.

Finding Indirect Evidence

Temperature – increases as you descend

Pressure (force pushing on a surface area)- the deeper you go the greater the pressure.

What it’s Like

1. Crusts Layer of rock that forms Earth’s outer skin

Includes both the dry land (continental) and ocean floor (oceanic)

Extra: Oceanic is DENSER so it sits BELOW the continental

The Layers of the Earth

density

the amount of mass in a given space

Cool Info!The deepest hole ever drilled into

the continental crust was in the Kola Peninsula, in Russia.

It was 12,226 meters deep!

Because the temperature of the crust increases with depth, it is impossible to drill much deeper into the crust.

2. MantleA layer of hot rockThe uppermost part of the mantle and

the crust together form a rigid layer called the lithosphere

Temperature and pressure in the mantle increase with depth

Layer beneath the lithosphere that is less rigid then the rock above it is the asthenosphere. The material in this layer can flow slowly

Extra: Sometimes it’s called the MESOSPHERE

The Layers of the Earth

Upper Mantle + Crust=Lithosphere

3. The coreMetal iron and nickel make up

both parts of the coreOuter core is a layer of molten

metal that surrounds the inner core (LIQUID)

Inner core is a dense ball of SOLID metal, where extreme pressure squeezes the atoms of iron and nickel so much that they cannot spread out and become a liquid.

The Layers of the Earth

What’s the main difference between the inner core and outer Core?

Currents in the liquid outer core force the solid inner core to spin at a slightly faster rate than the rest of the planet.

These currents in the outer core also create Earth’s magnetic field, which causes the planet to act like a giant bar magnet.

Earth’s Magnetic Field

Earth’s Magnetic Field

What Did We Learn?1. What are the four

main layers of the Earth?

2. What is the difference between the oceanic and continental crust?

3. What’s the difference between the inner and outer core?