Hadal zone

Deepest region of the ocean lying within oceanic trenches

The hadal zone, also known as the hadopelagic zone or hadalpelagic zone, is the deepest region of the ocean, lying within oceanic trenches. The hadal zone ranges from around 6 to 11 km (3.7 to 6.8 mi; 20,000 to 36,000 ft) below sea level, and exists in long, narrow, topographic V-shaped depressions. The total area is taken up by the 46 individual hadal habitats worldwide is less than 0.25% of the world's seafloor, yet trenches account for over 40% of the ocean's depth range.

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