Structure of the Earth

Introduction

• Earth is similar to a pizza, having layers like a crust.
• Main layers of the Earth: Crust, Mantle, Core.

The Earth's Crust

• Composed of rocks, soil, and everything above Earth's surface.
• Land crust is almost three times thicker than oceanic crust.
• Extends to about 25 miles.

The Mantle

• Lies beneath the crust.
• Composed of thick, solid, rocky materials.
• Accounts for about 85% of Earth's total mass.
• Thickness: Approximately 1800 miles.
  • First 50 miles: Hard, rigid rocks.
  • Next 150 miles: Super hot solid rocks.
  • Several hundred miles below: Very solid and sturdy rocks.

The Core

Outer Core

• Composed of super hot liquid molten substance: Lava.
• Believed to comprise iron and nickel.
• Extends to 3000 miles beneath Earth's surface.

Inner Core

• Extends another 900 miles toward Earth's center.
• Believed to be a solid ball made of iron and nickel.
• Hottest part of Earth, as hot as the surface of the Sun.

Trivia

• The crust occupies less than 1% of Earth's volume.
• Inner core is the hottest part of Earth.

Conclusion

• Understanding Earth's structure helps us learn more about our planet.
• Stay tuned for more fun facts in future sessions.