2. STRUCTURE OF THE EARTH By Andrew Patchak, Greg McGrath, Will Kugler

3. Core  Made up of iron and nickel it is the hottest part in the earth its temperature can reach up to 4000 to 7000 degrees C.  Inner core- it is made up of solid metal due to pressure.  Outer core- it is made up of a extremely hot metals  Mantle- it is a thin, hot layer under the Earth’s crust

4. Crust the outer layer of the earth is composed of soil and solid rock Continental crust- composed primarily of granite, is thicker sedimentary and metamorphic rocks which form the continents Oceanic crust- composed primarily of basalt, is thinner.

5. Plate Tectonics the theory of plate tectonics holds the earths crust is composed of mobile plates This movement is caused by thermal convection currents produced by the Earth’s mantle.

6. Continental Drift Theory- was first proposed by Alfred Wegener in 1912 It was not accepted until SONAR explored the ocean floor

7. Continental Drift Theory  The continents were once all joined to form one continent called Pangaea.  Pangaea broke into plates to form the continents.  the continents are still drifting apart.

8. Plates There are about twenty plates there are seven large plates and thirteen small plates. The largest plate is the Pacific Plate.

9. Plate movement Two plates moving the upper plate called the lithosphere and the asthenosphere. The cause of the plates movement is because the heat provokes the plate, the heat comes from the mantle.

10. Boundaries Colliding Boundaries- plates push against each other; formation of the Himalayas. Spreading Boundaries- plates are pulled apart; formation of the Great Rift Valley in Africa. Fault Boundaries- two plates moving past each other; formation of the San Andreas fault

11. QUIZ FILL IN THE BLANK 1. is composed primarily of basalt 2. there are about plates large and small 3. all continents were once joined to form one continent called,

12. Google images. the geological society.