| A | B |
|---|
| abyss | the greatest ocean-floor depths. |
| abyssal plain | a vast, flat area of the ocean floor |
| Southern Ocean | fourth largest oceannnear Antarctica |
| Arctic Ocean | Smallest and shallowest ocean,surrounded by land and mostly covered with ice, |
| Atlantic Ocean | second largest ocean between the Americas and Europe and Africa |
| black smokers | mineral chimneys on the ocean floor that release black smoke and hot water |
| continental rise | gently sloping area beween the continental slope and ocean floor |
| continental shelf | gently sloping underwater part of a continent |
| continental slope | The steeper sloping , area between the continental shelf and rise |
| guyot | an underwater volcano with a flat top |
| mid-ocean ridge | undersea mountain chain where new ocean floor is made |
| deep ocean trench | deep, steep-sided canyon in the ocean floor |
| Pacific Ocean | the largest ocean, covering about 1/3 of the Earth's surface |
| seamount | an underwater mountain |
| sonar | divice that sends sound waves into the ocean measures the time it takes for the sound to come back |
| submersible | underwater vehicle built to resist pressure |
| subsurface topograpyy | features located on the ocean floor and the changes in elevation they produce |
| Indian Ocean | the third largest ocean, bordered by Asia, Africa, and Antarctica |
