science

6. the circulation of material caused by differences in temperature and density.
7. when the denser plate sinks below the more buoyant plate
9. forms where two plates slide past each other
10. tectonics earth's surface is made of rigid slabs of rock or plates that move with respect to each other
13. the cold and rigid outermost rock layer
15. as a slab sinks it pulls on the rest of the plate with a force
16. form where two plates collide

1. a state in which magnetized objects would reverse direction and orient themselves to point south
2. the process by which new oceanic crust forms along a mid-ocean ridge and older oceanic crust moves away from the ridge
3. mountain ranges in the middle in the middle of the oceans
4. occurs and the magnetic field reverses direction
5. suggested that continents are in constant motion on the surface of earth
8. forms where two plates seperate
11. rising mantle material at mid-ocean ridges creates the potentail for plates to move away from the ridge with a force
12. a state in which magnetized objects such as compass needles will orient themselves to point north
14. all the continents were once part of a supercontinent