2. Inner Core Solid Diameter = 1480 km 3200 - 3960 miles below surface Temp = 9032 – 10,832 ºF (5000-6000 ºC)

3. Outer Core Plastic/ liquid 1990 Km thick 1,800 - 3,200 miles below surface Temp = 7200 - 9032 ºF (4000 - 5000ºC)

5. Mantle 2865 km thick (80% of earth’s volume) Temp = 5400 ºF (3000ºC) 3 distinct layers

6. Mesosphere Non-Newtonian substance

7. Asthenosphere Greek meaning ‘without strength’ 124 miles (200 km) thick 45–155 miles (72–250 km) below surface Plastic/ Liquid Temp = 2640 o F (1400 o C)

8. Andrija Mohorovičić First to use seismic waves to determine earth’s layers in 1909 Mohorovičić Discontinuity

9. Lower Lithosphere Brittle Broken

10. Upper Lithosphere or Crust Solid Broken into Plates High in Silica Rigid with some flexibility Two types of crust

11. Oceanic Crust 4-7 miles (6-11 km) thick Basalt Age is relatively young

12. Continental Crust Ave. thickness of 20 to 25 miles (30 to 40 km) Granite Much older than oceanic