Ocean Topo IAN 2
8. midocean ridge-undersea mountain range, the longest mountain range on Earth!
9. rift valley-deep valley in the midocean ridge formed where the sea floor is being pulled apart by plate tectonics, caused by divergent boundaries.
10. deep-sea trench-very steep sided cut (valley) in the ocean floor, deepest part of the ocean, can be more than 11,000 meters, caused by convergent boundaries.
11. Mariana Trench-deepest part of the ocean, over 36,000 feet deep. Water pressure is over 8 tons per square inch!!!