| A | B |
|---|
| continental shelf | The gently sloping part of a continent that is under water and rings each continent. |
| continental slope | The edge of a continent that drops steeply down to the deep-ocean floor. |
| abyssal plain | The vast floor of the deep oceans. |
| mid-ocean ridge | The place where plates of the Earth's crust along the ocean floor are being split apart and molten roch pushes up to form new ocean floor and a mountain range. |
| trench | A place where two plates of the Earth's crust hit each other, forming a deep part of the ocean. |
| seamount | A steep-sided volcanic mountain under the ocean. |
| atoll | A ring of islnds around a shallow central lagoon. |
| intertidal zone | The area between the high-tide mark and the low-tide mark. |
| coral reef | A structure built by sea creatures. |
| estuary | A place where a freshwater evironment and a saltwater environment meet |
| Photic Zone | Top layer of the ocean. |
| Aphotic Zone | The water below 200m and is totally dark. It has two parts. |
| Bathyal Zone | The same depth as the continental slope. |
| Abyssal Zone | Below 2000 meters. |
| Phytoplankton | primary producers in the ocean |
| sonar | machine that does echo sounding |
| fracture zones | areas of deep cracks in the rocks on the ocean floor |
| plankton | organisms that float freely on the ocean currents |
| diatom | single celled protists with glasy, jewel like shells |
| beach zone | just above the high-tide mark |
| subtidal zone | just below the low-tide mark |
| coquinas | small clams |
| tidal pools | hold water at low tides |
| Chesapeake Bay | large esutuary along the coast of Maryland |
