| A | B |
|---|
| Ocean Ridges | most pronounced tectonic feature on earth |
| Rift Valley | Crest of the Ocean Ridge |
| Divergent Boundary | Ocean Ridge is the location of this plate boundary |
| Africa, California and Iceland | Locations where ocean ridge system emerges onto continent |
| Transform Faults | Located perpendicular (normal) to ocean ridge systems |
| Abyssal Hills | Originally formed as ocean ridge, relatively low relief |
| Abyssal Plains | Flat featureless surface of ocean floor |
| Turbidity Currents | River-life flows of a sediment along ocean floor |
| Deep Sea Trenches | Subduction zone is expressed topographically as this |
| Most deep sea trenches occur in this ocean | Pacific Ocean |
| Volcanic Islands | Volcanic cones that reach the ocean surface |
| Atoll | Created when a volcanic island with growth of coral keeps pace as it subsides |
| Guyot | Drowned volcanic islands that did not become atolls |
| Seamount | Underwater volcano with a small rounded top |
| Continental Shelf | Flat area with low slope adjacent to continent |
| Continental Slope | Steep slope area of seafloor |
| Major Ocean Basins | Atlantic, Indian and Pacific |
| Average depth of ocean basins | 3800 meters (=3.8 km) |
| Youngest ocean basin | Atlantic Ocean |
| Ocean basin decreasing in size | Pacific Ocean |
