1. Chap 7, Sec 1 (Inside the Earth)
Objectives:
Identify the layers of the Earth by their chemical (elements) composition.
Identify the layers of the Earth by their physical properties.
Describe a tectonic plate.

2. What do we already know about Earth's Structure?
Chapter 7
What do we already know about Earth's Structure?

3. Physical Tech Terms:
Earth’s crust –
layer of rock
forms Earth’s outer skin
contains rocks, mountains, soil, and water
can range in thickness from km thick
the thinnest layer of the Earth.

4. separated from the crust by the Mohorovicic discontinuity
mantle –
separated from the crust by the Mohorovicic discontinuity
composed of silicon, oxygen, magnesium, iron, and calcium
acts as an amorphous solid (solid and liquid tendencies).
It’s the thickest!

6. lithosphere - the crust + the rigid upper mantle.
asthenosphere – located about 100 km to 250 km deep underground that exhibits plastic properties.

8. How do we know this?

9. Journey to the Center of the Earth
In 1864 a novel was written on this topic by French author Jules Verne.
At the time, scientists knew nothing about the Earth’s interior. Was it hollow? Was it solid? Hot or cold?
How could you travel through the Earth? You would need a vehicle that could travel through solid rock, adjust your body to extreme pressures, and resist heat as hot as 5,000 degrees C.

10. Finding Indirect Evidence
One of the most difficult questions that geologists try to answer is, What’s inside the Earth?
Seismic Waves measure the distance and route of travel through the earth’s crust.
These are also used for measurement of earthquake strength and predictions.
Discovery of the Earth's Core

11. The Earth’s core contains two parts that make up about 1/3 of Earth’s mass, both which are made of iron and nickel.
outer core –
layer of molten, liquid, metal (despite the amount of pressure it is under)
2,260 km thick.

12. inner core –
dense ball of solid metal
1,200 km thick
temperature which is slightly hotter than the surface of the sun (7,200 °C)
It’s the hottest AND densest!

14. MIT Layers of the Earth video

15. Independent Reinforcement
1) Silent Read p
2) Complete the guided reading worksheet with it minutes.
Layers of the Earth Rap