The abyssal zone, or the abyss, is the seafloor and water column from 3,000 to 6,500 meters (9,842 to 21,325 feet) depth, where sunlight doesn’t penetrate. Hadal Zone The region extending from 6,000 to 11,000 meters is called the hadal, or hadalpelagic, zone after Hades, the Greek god of the underworld. More @Wikipedia
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