oceanagraghy

6. Zone The layer of the ocean at depths between 4,000 and 6,000 meters.
8. Zone The middle layer of the ocean, receiving very little light.
11. Zone The uppermost layer of the ocean, where sunlight penetrates.
14. A flat, almost level area of the deep-ocean basin.
15. Organisms that live on, in, or near the seabed.
17. An underwater mountain range formed by plate tectonics.
18. Aquatic animals that can swim and move independently of water currents.
19. The concentration of salts in water.
20. A series of ocean waves with extremely long wavelengths caused by large-scale disturbances.

1. An opening in the sea floor out of which heated mineral-rich water flows.
2. Zone The deep ocean layer, where no sunlight reaches.
3. A layer in a body of water where the temperature changes rapidly with depth.
4. The steep slope where the continental shelf drops to the deep ocean floor.
5. Reef A diverse underwater ecosystem held together by calcium carbonate structures secreted by corals.
7. The rising of cold, nutrient-rich water from deep in the ocean to the surface.
9. Small and microscopic organisms drifting or floating in the sea.
10. Zone The deepest layer of the ocean, found in ocean trenches.
12. An underwater mountain rising from the ocean floor that does not reach the surface.
13. The extended perimeter of each continent, which lies submerged under relatively shallow seas.
16. A deep, narrow depression in the ocean floor, often caused by tectonic activity.