| A | B |
|---|
| Continental Margin | region of the sea floor that contains the shelf and slope |
| continental shelf | part of the continent that is underwater |
| Ocean basin floor | begins where the slope ends, region made up of mountains, riges, trenches, valleys, rifts,guyots,abyssal plains, and canyons plateus ,ch |
| abyssal plain | vast smooth areas on sea floor |
| Trenches | cracks in the earths crust, deepest part of the ocean |
| guyots | flat topped volcanic mountains |
| rift | a valley that runs along the center of a ridge |
| seamount | isolated mountains that rses more than 3000 ft. above the sea floor |
| mid-ocean Ridge | great undersea mountains ranges characterized by frequent earthquakes and volcanoes |
| island | seamount that rises above the surface of the water |
| 75% of the earth's surface | mostly water |
