Plates

3. a device that uses sound waves to measure distance to an object
6. floor spreading forms along with a crack in the oceanic crust
8. breaks in earth's crust where rocks have slipped past each other
10. trench deep water canyons
12. drift continents slowly moved over earth's surface
14. a scientist that is curious about continents
15. valley pieces of earths crust diverge on land and a deep valley call forms

1. continents that join together as a super continent or singe land mass.
2. any trace of an ancient organism that has turned into a rock.
4. ridge seams that formed mountain ranges
5. tectonics the theory of plate tectonics states that earth's plates are in slow constant motion driven by convection currents in the mantel
7. boundary plates that come together or converge
9. ocean floor sinks beneath the deep ocean trench
11. boundary plates move apart or diverge from each other at?
13. boundary plates that slip past each other