Oceans cover 70% of the Earth’s surface and help regulate climate conditions. Warm ocean currents move water away from the equator, whereas cold ocean currents move water away from the cold regions toward the equator. The warm Gulf stream, for instance, transports 55 million cubic meters of water per second. Without it, the temperature lands of northwest Europe would be more like the sub-Arctic.
Features of the ocean floor
- Island arc
- Deep sea trench
- Deepest part of the ocean, caused from one ocean subducted under a continental plate
- Guyot
- Flat topped volcano that reached the surface but later subsided
- Transform fault
- Feature of ocean ridges, fracture zones at right angles to the main ridge
- Seamount
- Extinct volcanoes
- Submarine canyon
- Located close to a point where a large river flows to the sea
- Abyssal plain
- Edge of the continental slope, cover large areas, depths between 4000 and 6000 meters, generally flat and featureless
- Continental rise
- Continental slope
- Steeply sloping area of seabed, stretches from continental shelf to abyssal plain. Can have submarine canyons eroded by fast flowing currents.
- Continental shelf
- Flat area of seabed, less than 250 meters deep up to 70km wide
- Mid-ocean ridges
- Largest features of the ocean, linear belt of submarine mountains. Occur where there are divergent (constructive or spreading) tectonic plate boundaries. Magma forces its way up forming large valley
- Largest features of the ocean, linear belt of submarine mountains. Occur where there are divergent (constructive or spreading) tectonic plate boundaries. Magma forces its way up forming large valley
IB Geography 2018 