ocean floor
Deepest terrain below
The ocean floor is the ground at the bottom of the sea—the solid surface beneath all that water.
It includes trenches, ridges, plains, and volcanic formations, much of it unexplored.
Scientists mapped the ocean floor using sonar.
Also called the seabed or sea floor.
Marine skeletal formation
- kelpLarge brown marine algae
- seagrassSaltwater flowering plant
- phytoplanktonPhotosynthetic aquatic drifters
- zooplanktonDrifting aquatic microorganisms
benthos · reef · hydrothermal vents · chemosynthesis · bioluminescence · tube worms · anglerfish · giant squid
Long narrow excavation
- seamountSubmerged volcanic elevation
- submarine canyonUnderwater valley cutting continental shelf
- plate tectonicsEarth's crust mobility theory
- subductionPlate descending beneath another
basalt · sediment · magma · lithosphere · silicates · volcanic · lava flows · earthquake
Extremely deep, unmeasurable
- benthicOf the sea bottom
- fathomlessImmeasurably deep or obscure
- pressureForce upon contact
- darknessTotal absence of light
trenches · Mariana · Challenger Deep · abyss · deep-sea · bottom · sunken · submarine
Underwater exploration vehicle
- ROVPiloted-from-above underwater craft
- bathyscapheSelf-propelled deep-diving craft
- sonarUnderwater detection by echoes
- divingEntering water deliberately
mapping · expedition · research · Trieste · Alvin · James Cameron · scientists · technology
Not yet discovered
- unexploredNot yet investigated
- hiddenKept out of sight
- sunkenDescended beneath water level
- enigmaticPuzzling and obscure
alien · otherworldly · uncharted · secretive · lost · ancient · shipwrecks · artifacts
coral
Marine skeletal formation
- kelpLarge brown marine algae
- seagrassSaltwater flowering plant
- phytoplanktonPhotosynthetic aquatic drifters
zooplankton · benthos · reef · hydrothermal vents · chemosynthesis · bioluminescence · tube worms · anglerfish · giant squid · sea cucumbers
trench
Long narrow excavation
- seamountSubmerged volcanic elevation
- submarine canyonUnderwater valley cutting continental shelf
- plate tectonicsEarth's crust mobility theory
subduction · basalt · sediment · magma · lithosphere · silicates · volcanic · lava flows · earthquake · bathymetry
abyssal
Extremely deep, unmeasurable
- benthicOf the sea bottom
- fathomlessImmeasurably deep or obscure
- pressureForce upon contact
darkness · trenches · Mariana · Challenger Deep · abyss · deep-sea · bottom · sunken · submarine · crushing
submersible
Underwater exploration vehicle
- ROVPiloted-from-above underwater craft
- bathyscapheSelf-propelled deep-diving craft
- sonarUnderwater detection by echoes
diving · mapping · expedition · research · Trieste · Alvin · James Cameron · scientists · technology · underwater
unknown
Not yet discovered
- unexploredNot yet investigated
- hiddenKept out of sight
- sunkenDescended beneath water level
enigmatic · alien · otherworldly · uncharted · secretive · lost · ancient · shipwrecks · artifacts · Atlantis
- oceansdeep sea, seabed, Gulf Stream, Mariana Trench, marine life
- underwater placesunderwater cave, underwater canyon, underwater tunnel, seabed, sea bed
- beneath the surfaceunderground, underwater, submerged, caves, aquifers
- deep seaabyss, seabed, seafloor, deep sea, depth
- marine habitatskelp forest, kelp forests, estuaries, tide pool, tide pools
- ocean floorseafloor, seamount, seamounts, submarine canyon, hydrothermal vent
ocean floorocean surface
Top of the sea
sea surface · water surface · surface waters · sea level · surface layer
ocean floordry land
Earth above water
land surface · terra firma · ground level · shore · coastline
ocean floormountaintop
Summit of a peak
mountain peak · summit · mountain summit · highest peak · Everest
floor, ocean, oceans, flooring, oceanic, oceanography, oceanographer, transoceanic, oceanarium