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The Global Ocean The five oceans from smallest to largest are: the Arctic, Southern, Indian, Atlantic and Pacific.
These five oceans are connected and are actually one huge body of water, called the global ocean or just the ocean. If you were to add the smaller seas like the Barents, Beaufort, Chukchi, Kara, Laptev, East Siberian, Lincoln, Wandel, Greenland and Norwegian, etc. you would have a total area of the ocean of about 361,000,000 km² (which is ~71% of the Earth's surface), a total volume of roughly 1,370,000,000 km³, and an average depth of 3,790 m. Our hydrosphere (ocean plus all freshwater in ground water, lakes, rivers, snow, ice and the atmosphere) makes up about 0.023% of the total mass of the Earth.
The word “Ocean” comes from Okeanos, the Greek god of the Ocean.
Terrigenous, pelagic, and authigenic materials composes most of ocean sediments. Erosion, weathering and volcanic activity on land washes out to sea and creates the sand, mud, and rock particles that make up terrigenous deposits. Consequently, terrigenous deposits are confined to narrow marginal bands close to land like continental shelves and are deepest near the mouths of large rivers or desert coasts. Pelagic deposits derived from seawater are red clays and the skeletal remains of organisms that have died and sunk to the ocean floor. These include pelagic red clays and globigerina, pteropod and siliceous oozes. Most of the ocean floor is actually covered in these organic remains with a depth ranging anywhere from 60 to 3,300 m deep, but they are thickest in convergence belts and upwelling zones. Authigenic deposits are made up of particles like manganese nodules and include montmorillonite and phillipsite and can be found in places where the sedimentation process occurs very slowly or currents sort out the deposits.