Which Is the Deepest Ocean?

The Pacific Ocean is both the largest and deepest ocean, with an average depth of about 4,280 metres. Its deepest point, the Challenger Deep in the Mariana Trench, plunges to 10,994 metres below sea level — deeper than Mount Everest is tall. The Pacific covers about 165 million km², more than all the land on Earth combined. The extreme depths of the Mariana Trench result from the subduction of the Pacific Plate beneath the smaller Mariana Plate. Despite the crushing pressure (over 1,000 atmospheres) and perpetual darkness, life exists at the bottom, including amphipods and xenophyophores.