1. Inside the Earth Mr. Reed Earth Science Madras Middle School

2. What is Inside Earth? • We are not sure? Why? • Extreme conditions inside Earth • Temperature rises • Why? Heat left over from formation of planet and radioactive substances inside Earth’s interior releasing energy • Pressure increases • Because of the weight of the rock above

3. How do we study the inside of the Earth • Rock Samples • Geologists can drill into the Earth and bring up rock samples • Theses samples allow scientists to infer about conditions inside Earth • Seismic Waves (Earthquake waves) • Geologists study how the seismic waves travel through Earth (speed and path) • This data has help geologists realize that the Earth is made up of several different layers

4. Composition (What it is made of) • Crust • Mantle • Core

5. Outer layer Solid Rock 5-70 km thick 2 types of crust Oceanic (very thin, made of basalt) Continental (thicker, made of granite) The Crust

6. Middle layer Very thick layer 3000 km thick Very hot , but solid rock Made up of three sublayers: 1. lithosphere 2.asthenosphere 3.lower mantle The Mantle

7. The Mantle • Lithosphere • Uppermost part of the mantle • 100 km thick • Lower Mantle • Solid material that extends to the core • Asthenosphere • Bottom part of the mantle • Less rigid, soft rock • Can bend like plastic

8. The Core • Made mostly of metal irons and nickel • Very hot • 3,486 km thick • Made up of 2 parts: • Outer core and the inner core

9. The Core • Outer Core • Molten metal • LIQUID LAYER • Inner Core • Solid Metal

10. Earth’s Magnetic Field • Movement in Earth’s outer core create Earth’s magnetic field

11. How are the earth’s layers similar to an egg? Shell=crust Egg white=mantle Yolk=core Earth’s Layers