Chapter 7 Section 1Pgs 190-193

Composition of the EarthDivided into 3 layers:• Crust• Mantle• Core

Compound – substance made of two ormore elements

CRUST• The outermost layer• 5-100 km thick• Thinnest layer

2 types of crust:• Continental- thick• Oceanic-thin

MANTLE• Between the crust and core• Thick• Contains most of Earth’s mass• Scientists can’t get to it so they study it by

looking at magma from volcanoes

CORE• From the mantle to the center of Earth• Innermost layer• Makes up 1/3 of Earth’s mass

Physical Properties of Earth

Divided into 5 physical layers:• Lithosphere• Asthenosphere• Mesosphere• Outer Core• Inner Core

Lithosphere

• Outermost layer - rigid• Made of crust and upper mantle• Divided into pieces called tectonic plates.

Asthenosphere• Below Lithosphere• Pieces of lithosphere (called tectonic

plates) move on top of this layer• Made of solid rock that flows slowly

Mesosphere

• Below the asthenosphere• Strong lower part of mantle• Extends to the Earth’s core

Outer Core

• Liquid layer of core• Surrounds inner core

Inner Core

• Solid dense center

Quiz1. Name the three main layers of the Earth.2. Which layer is the most dense?3. Which layer is the thinnest?4. What are the two types of crust?5. Which layer contains most of Earth’s mass?6. What two layers make up the lithosphere?7. The lithosphere is divided into pieces called:8. Pieces of lithosphere move on top of this layer:9. The Asthenosphere is said to be “plastic”. What does this

mean?10. Which layer, inner core or outer core, is liquid?11. Which layer, the inner core or the outer core, is solid?

Answers1.Crust, mantle and core2. Core3. Crust4. Continental and oceanic5. Mantle6. Crust and upper mantle7. Tectonic Plates8. Asthenosphere9. Because it is very hot and made of partially molten rock it bends and

can be pushed and deformed due to the pressure placed on it from deep within the Earth.

10. Outer core11. Inner core