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The Earth's Interior

Chapter 8

Objectives:-Describe the composition of the Earth's inner and outer core.

-Identify the main features of the Earth's mantle.

-Define the term lithosphere.

-Differentiate between oceanic and continental crust.

-Define the term asthenosphere.

-Explain how geologists were able to construct a model of the Earth's interior.

Terms to Know:-Lithosphere -Mantle -Earth's core-Convection cells -Radioactive Decay -Friction-Residual heat -Crust -Oceanic crust-Continental Crust -Asthenosphere -Inference

________________

__________________

________________

_________________

________________

The Earth's Interior

The Earth's interior consists of a solid inner core, a liquid outer core, mantle, and crust.

The Earth's Core

-The very _________ of the Earth.

-Composed of _____ layers.

-Composition of both layers is believed to be ________ and __________.

1,800 mi (2,897 km) to reach outer core

3,200 mi (5,100 km) to reach inner core

Earthquake generate seismic waves that ripple through the solid Earth

When P waves reach the solid layer, they bend again.

When P waves hit the liquid or partial liquid layer, they bend.

All that bending of waves creates a 'shadow' where no P waves reach seismographs on the Earth's surface.

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Temperatures in the Core

Temperature in Fahrenheit

7,200

9,000

Depth in Miles

1,250

2,500

4,000

-Temperatures up to 8,000 F (4,427 C)

-Heat generated by _______________, __________, and residual _______ left over when the planet formed.

The Mantle-Makes up most of the Earth's total ______________.

-Composed of hot _________ material consisting of:-silicon-oxygen-iron-aluminum-magnesium

-Exposed to extremely high _______________.

1,800 mi (2,897 km) thick

The LithosphereSolid outer portion of the Earth's interior composed of the solid ____________ and the upper portion of the ____________.

-Upper part of the ____________.-Composed of a ______________ material.-Heat from the core rises up through the mantle creating ____________________.

Asthenosphere

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The Crust• Outer part of the Earth composed of solid rock which "floats" on the _____________.

• 99% of the crust is composed primarily of:-___________* -_________* -aluminum-iron -calcium -magnesium-sodium

Crust

*Make up _____% of the rocks in the crust

Oceanic Crust• Less than ___ mi (10 km) thick

• Average density of ___ g/cm3

• Composed of mainly ____________ rocks formed under pressure.

Continental CrustAs much as ____ mi (64 km) thick

Average density of _____ g/cm3

Composed mainly of _________ rocks

Review QuestionsPage 179Questions 1 ­ 6

Earth MathPage 179Questions 1