1. Inside Earth Chapter One Section 1 Plate Tectonics

2. 1.1 Earth’s Interior Key Concepts How have geologists learned about Earth’s inner structure? Geologists use two main types of evidence: a.Direct evidence – Look at rocks b.Indirect evidence – Seismic waves

3. 1.1 Earth’s Interior Key Concepts What are the characteristics of Earth’s Crust – The layer of rock that forms Earth’s outer surface. Mantle – The layer of hot, solid material between earth’s crust and core. Core – The center of the planet Earth.

4. 1.1 Earth’s Interior Key Terms Basalt – A dark, dense, igneous rock with fine texture, found in ocean crust. Granite – A usually light-colored igneous rock that is found in continent crust. Lithosphere – A ridged layer made up of the uppermost part of the mantle and the crust. Asthenosphere – The soft layer of the mantle on which the lithosphere floats.

5. 1.1 Earth’s Interior Key Terms Outer core – A layer of molten iron and nickel that surrounds the inner core of Earth. Inner core – A dense sphere of solid iron and nickel at the center of the Earth.

6. 1.1 Earth’s Interior Key Terms Seismic waves – Vibrations that travel through Earth carrying the energy released during an earthquake. Pressure – The force exerted on a surface divided by the area over which the force is exerted.

7. 1.1 Earth’s Interior A Journey to the Center of Earth Three main layers are the crust, the mantle, and the core Temperature – At the start the temperature is cool until approximately 20 meters. Then it begins to grow warmer. For each 40 meters the temperature rises 1* Celsius. Pressure - Because of the weight of the rock above the pressure increases the deeper you go.

8. 1.1 Earth’s Interior The CRUST – This is the Earth’s outer skin. The ocean crust is thinner, denser, dark Mostly Basalt The continent crust is thicker, lighter, less dense Mostly Granite

9. 1.1 Earth’s Interior The MANTLE – About 40 Kilometers beneath the surface. Approximately 3,000 kilometers thick This layer is very hot and solid The mantle has TWO (2) main layers 1-Lithosphere = upper mantle, similar to the crust. 2-Asthenosphere = hotter increase pressure less rigid, like road tar can bend like plastic. 3-Lower mantle = solid all the way to the core.

10. 1.1 Earth’s Interior The CORE Is mostly iron and nickel It has two layers Outer core – a layer of molten liquid rock ( the movement of this liquid outer core layer is what gives earth a magnetic field ) Inner core – a dense ball of solid metal