Seafloor Spreading

3. Wegener's theory that continents were all together at one point
4. what we use to map seafloor that we cannot physically get to (sound waves)
6. fracture zone, a break in earth's crust
8. new lithosphere continuously forms at the mid-ocean ridge
10. scientist who mapped the seafloor and discovered the rift valley on the ocean floor
11. places where crust shows signs of being pulled and stretched
12. a well established idea that is supported by a large amount of evidence

1. waves that occur from earthquake and volcanic activity
2. a large crack on the ocean floor where new seafloor is created
5. a concentrated zone of volcanic and earthquake activity on earth
7. the theory that plates move across earth's surface
9. the crust and upper mantle that create plates and "float" on top of the lower mantle