| A | B |
|---|
| Continental Margin | Region of the sea floor that contains the shelf and slope |
| Continental Shelf | Part of the continent that is underwater |
| Continental Slope | Where water deepens abruptly and the edge of the continental land mass drops off |
| Ocean Basin Floor | Begins where the slope ends, regions made up of mountains, ridges, trenches, valleys, rigts, guyots, abyssal plains, and canyons plateau |
| Abyssal Plain | Vast smooth area on floor |
| Trenches | Cracks the earth's crust, deepest part of the oceans |
| Guyots | Flat topped volcanic mountains |
| Rift | A valley that runs along the center of a ridge |
| Seamount | Isolated mountain that rises more than 3000 ft above the sea floor |
| Mid-ocean Ridge | Great undersea mountain ranges characterized by frequent earthquakes and volcanoes |
| Island | Seamount that rises above the surface of the water |
| Water coverage | 75 percent of the earth's surface is covered with water |
