1. Which branch of Earth Science would study earthquakes?

2. Which branch of Earth Science would study hurricanes?

3. Which branch of Earth Science would study the warming of the oceans’ waters?

4. Which branch of Earth Science would study asteroids?

1. Name the layers of the Earth.

2. What is the thickest layer of the Earth?

3. What is the thinnest layer of the Earth?

4. What is the hottest layer of the Earth?

1. The crust is about ___________ km thick.

2. True or False. The mantle is a liquid.

3. The deeper you go into the Earth the ________ the temperature.

4. The densest layer of the Earth is the ________.

• What are the layers of the Earth?• What is the crust?• What are the characteristics of the Earth’s Crust?• What is the composition of the Earth’s Crust?• What is the lithosphere?• What is the Moho?• What is the mantle?• What are the characteristics of the Earth’s Mantle?• What is the composition of the Earth’s Mantle?• What is the asthenosphere?• What is the mesosphere?• What is the core?• What is the outer core?• What is the inner core?

• Crust• Mantle• Core – Outer Core

and Inner Core

• The crust is the outermost layer of the Earth• Thickness: 5 to 100 kilometers thickContinental Crust: ~ 30 kmOceanic Crust: ~ 5 km

• Crust floats on the mantle.• Crust is thin.• Two layers – Top layer of granite and a more

dense bottom layer of basalt. Both layers are found under continents, only the basalt layer is under the oceans.

• Temperatures increase with depth: 20° C at top and 870° C at bottom.

Crust is composed of:• Oxygen: ~ 50%• Silicon: ~ 30%• Aluminum: ~ 10%

50%

30%

10%

10%

Crust Composition

Oxygen

Silicon

Aluminum

Other

Moho:• Boundary between the crust and the mantle that is

more dense than the crust.

Lithosphere:• Made up of crust and uppermost layer of the

mantle.• Approximately 80 km thick.• Broken into pieces (tectonic plates) which move

around on the asthenosphere.

• The mantle is the thickest part of the Earth.• Thickness: ~ 2,900 km• Upper and Lower Mantle – they differ in

temperature, density, and pressure. These increase as depth increases.

• Temperatures: Top of mantle is ~ 870° C and bottom is ~ 2,200° C.

• Rock begins to flow like dough as temperature increases.

Composition:• Silicon, Oxygen, Iron, and Magnesium• The deeper the rocks are in the mantle, the more

iron they hold.

Asthenosphere:• Upper part of the mantle.• Found between 75 km and 200 km deep.• Semiplastic layer which moves fluidly due to

convection currents.

Convection Currents:• Circular movements caused by the

heating and cooling of the substance.

Mesosphere:• Layer of the mantle below the asthenosphere.• 350 to 2,900 km deep.• Great pressure - it is solid and more rigid than the

rock on top of it.

• Innermost layer of the Earth.• Two layers – Outer Core and Inner Core• Thickness: Outer Core is ~ 2,250 km thick and

Inner Core is ~ 2460 km in diameter.

Outer Core:• A shell surrounding the inner core.• Composed of liquid iron and nickel.• Temperature: ~ 2,200° C at its outer surface

and ~ 5,000° C at its inner surface.

Inner Core:• Innermost layer of the Earth – Sphere.• Composed of solid iron and nickel.• Temperature: ~ 5,000° C.• Solid due to extreme pressure bearing down.