1. Chapter 1: Introducing Earth Lesson 1: Review of Earth’s System
Earth’s Structure
Chapter 1: Introducing Earth
Lesson 1: Review of Earth’s System

2. The Earth System
System: a group of parts that work together as a whole.
Energy allows Earth to work as a system as it moves matter through its parts.

3. The Atmosphere
The relatively thin envelope of gases that forms Earth’s outermost layer.
Mostly made of nitrogen and oxygen.

4. The Geosphere The geographic makeup of the Earth.
Three main parts: a metal core, a solid middle layer, and a rocky outer layer.

5. The Hydrosphere Contains all of Earth’s water.
About ¾ of Earth’s surface is covered, but more water can be found underground and in different parts of the water cycle.

6. The Biosphere
The parts of Earth that contain living organisms.

7. Constructive Forces
Forces that construct, or built up, mountains are constructive forces.
This often happens from
the collision of two
tectonic plates – sections
of Earth’s lithosphere that
move slowly over Earth.

8. Destructive Forces
Destructive forces destroy and wear away landmasses through processes such as erosion and weathering.
Remember: weathering is the breaking down of particles, erosion is them being carried away.

9. Chapter 1: Introducing Earth Lesson 2: Earth’s Interior
Earth’s Structure
Chapter 1: Introducing Earth
Lesson 2: Earth’s Interior

10. Earth’s Interior
Scientists gather information about Earth’s interior in two main ways:
Rock samples: geologists have drilled up rock samples from 12.3 km into Earth.
Seismic waves: geologists record waves after an Earthquake and measure the speed and paths taken by the waves to indicate how materials change inside Earth.

11. Earth’s Interior

12. Earth’s Layers
There are three main layers of the Earth – the crust, the mantle, and the core.
The deeper you go into Earth, the more pressure there is and the greater the temperature is.
Pressure: the result from a force pressing on an area.

13. The Crust
Crust: the layer of rock that forms Earth’s outer skin; layer of solid rock on land and on the ocean floor.
Mainly made of two elements: oxygen and silicon.
Usually between 5-40 km thick; thickest below mountains and thinnest at the ocean floor.

14. The Crust Crust beneath the ocean is called oceanic crust.
Mostly composed of basalt, a dark, fine-grained rock.
Crust that forms the continents is called continental crust.
Made of many types of rocks, but most like granite, a rock that is light in color with coarse grains.

15. The Mantle
The mantle is made of up rock that is very hot, but solid, and contains more magnesium and iron than the crust.
About 3,000 km thick.
Broken into 3 layers.

16. The Mantle Lithosphere - Asthenosphere –
The crust and uppermost mantle; strong, hard, rigid rock.
Asthenosphere –
Solid, but can bend slightly; due to increased heat and pressure it is less rigid.
Mesosphere (transition zone) –
Lowest layer; becomes more rigid again

17. The Core Mostly made of iron and nickel. Liquid outer core
2,258 km thick
Molten metal
Solid inner core
1,222 km thick
Very dense

18. The Layers of the Earth

19. The Magnetic Field
Movement in the outer core has created the magnetic field, causing the planet to act like a magnet.
The Earth’s magnetic north pole is not the same location at the Earth’s geographic North pole.

20. The Magnetic Field

21. Chapter 1: Introducing Earth Lesson 3: Convection and the Mantle
Earth’s Structure
Chapter 1: Introducing Earth
Lesson 3: Convection and the Mantle

22. Transferring Heat
When an object is heated, the particles move more quickly because they have more energy.
Heat is transferred in three main ways:
Conduction: direct contact between two objects
Radiation: the transfer of heat through electromagnetic waves
Convection: the transfer of heat through the mixing of liquids/gases

23. Transferring Heat

24. Convection in the Mantle
Convection is caused by changes in density: a measure of how much mass there is in a given volume of a substance.
Less dense materials rise to the top, while more dense materials sink to the bottom. Over time, these materials heat and cool to keep rising and sinking.

25. Convection in the Mantle
A convection current is caused by the heating and cool, change in density, and force of gravity moving liquids and gases.
Heat from the core heats the materials in the mantle, creating a convection current.