Oceans matching game Tools A B Upwelling Rising of deep cold water saturated with nutrients NaCl Most abundant salt in ocean water Oxygen and Hydrogen Most abundant elements in ocean water N2, CO2, O2 Most abundant dissolved gasses in ocean water Surface Zone Where water is mixed by currents and waves Thermocline Quick temperature drop Deep Zone Area of extremely cold water Continental Shelf Gently sloping ocean floor from shoreline, great fishing Abyssal Plain Flat area on ocean floor Seamount Underwater volcano Guyot Flat topped seamount eroded by waves Trench Deepest area of ocean floor Coral Reef Calcium carbonate island community Plankton Microscopic plants & animals Nekton Swimming: fish, whale, dolphin Benthos Live on ocean floor: starfish, crab, oyster Intertidal Zone Area b/w low and high tide Neritic Zone Area b/w low tide and continental shelf Open-ocean Zone Largest area of the ocean Wave Pulse of energy that moves through water