| A | B |
|---|
| abyssal plain | the flat bottom of the ocean floor |
| about 70% | the amount of the Earth's surface covered by the ocean |
| ocean trench | a deep-sided canyon on the ocean floor |
| continental shelf | the part of the ocean floor closest to the shore |
| about 45% | the amount of the Earth's surface covered by the abyssal plain |
| seamount | under water mountain from vocanic eruptions |
| continental rise | lower part of the continental slope |
| continental slope | a sharp drop off from the continental shelf |
| covers much of the ocean floor | sand, mud, and rocks |
| Marianas Trench | the ocean's deepest trench |
