| A | B |
|---|
| Continental Margin | Region of the seafloor that contains the shelf and slope |
| Continental Shelf | Part of the continent that is underwater |
| Continental Slope | Where the water deepens abruptly and the edge of the continental land mass drops off |
| Ocean Basin Floor | Begins where the slope ends, region made up of mountains, ridges, trenches, valleys, rifts, guyots, abyssal plains, and canyon plateau |
| Ayssal Plain | Vast smooth areas on the sea floor |
| Trenches | Cracks on the Earth's crust, deepest part of the oceans |
| Guyouts | Flat topped volcanic mountains |
| Rift | A valley that runs along the center of a ridge |
| Seamount | Isolated mountain that rises above the more than 3,000 feet above the seafloor |
| Mid-Ocean Ridge | Great mountain ranges characterized by frequent earthquakes and volcanoes |
| Island | Seamount that rises above the surface of the water |
| 75% | of the earth is covered by water |
