Answer questions 1 through 5 with at least 3 complete sentences for each question. Be specific with your answers.

1. Which type of heat transfer is thought to occur in the mantle that helps fuel plate tectonic movement?
2. What happens to oceanic lithosphere over time, as it ages?
3. Why are continents so much older than the ocean basins?
4. Where in the world’s oceans are the oldest rocks? How old are they?
5. Where does all new ocean crust form? Why?
6. Enter the terms in the left column into the appropiate boxs.
   

   Terms	Oceanic Lithosphere	Continental Lithosphere
   New rocks forming Old rocks melting Contains oldest rocks Contains youngest rocks Less than 250 million years Older than 250 million years High Density Low Density

7. Label each diagram (A, B, and C) as either convergent plate boundary, divergent plate boundary, or transform plate boundary.
8. You find a 10,000,000 year old rock 2,500 km away from the nearest seafloor spreading center, how fast has the plate been moving since its formation? Give answer in cm/yr. (Hint: 1 km = 100,000 cm)
9. You find a rock 7,500 km away from the nearest seafloor spreading center. The plate is spreading at 5 cm/year, how old is the rock? Give answer in years. (Hint: 100,000 cm = 1 km)
10. You find a 2,400,000 year old rock formation on a plate that is spreading at 12 cm/year, how far is the rock formation from the spreading center? Give answer in kilometers. (Hint: 100,000 cm = 1 km)