| A | B |
|---|
| Abyss | a deep space, gulf, or cavity that extends from 4,000 meters to 6,000 meters |
| abyssal plain | the flat part of the ocean floor (3500-6,000m deep) |
| continental rise | pile of sand and sediments at the base of the continental slope; curves down from the slope to the ocean floor (4000-5,000m deep) |
| continental shelf | the land around the edge of a continent that is under the shallowest water (150-200m deep) |
| continental slope | the steep drop-off in the seafloor that extends from the shelf down to the rise (200m- 4.000m deep) |
| crest | the top of a wave before it breaks |
| currents | streams of water within the ocean; can be caused by wind or water temperature and salinity deeper in the ocean |
| depth | the distance below the ocean’s surface |
| Gulf Stream | a major ocean current on the east coast of the United States |
| Midnight Zone | the area that extends from 1000 meters to 4000 meters; pitch black due to no sunlight at all; extreme pressure due to depth |
| ocean ridges | mountains found on the ocean floor where plates of the Earth come together |
| ocean trenches | deep cracks in the flat bottom of the ocean floor ( up to 11,000m deep) |
| phytoplankton | plant-like organisms that produce most of the Earth’s oxygen and serves as the base of the oceans ecosystem |
| plankton/zooplankton | small floating organisms that eat the phytoplankton |
| salinity | a measurement of the amount of salt dissolved in water |
| seamount | an underwater mountain that lies completely below the sea (also called an ocean ridge) |
| Sunlight Zone | the area that extends to a depth of 200 meters; well lit by sunlight and most of the oceanic food is produced and found there |
| tides | the rise and fall of the oceans due to the gravitational pull of the moon and, to a lesser degree, the sun |
| trench | deep valley on the bottom of the ocean |
| trough | the bottom portion of a wave |
| Twilight Zone | the area that extends from 200 meters to 1000 meters; some light is found there (Most organisms there are consumers and come up to the Sunlight Zone to feed.) |
| wave | a disturbance seen on the surface of the water caused by winds |
| spring tide | The greatest changes from high to low tide that occur when the Sun, the Moon, and Earth are lined up |
| neap tide | The slightest changes from high to low tide that occur when the Sun, the Moon, and Earth form a right angle or are perpendicular to each other. |
| mid-ocean ridge | Chain of mountains that wind along all the world's major oceans. |
