Abyssal zone

Deep layer of the ocean between 4000 and 9000 meters

The abyssal zone or abyssopelagic zone is a layer of the pelagic zone of the ocean. The word abyss comes from the Greek word ἄβυσσος (Ancient Greek: ἄβυσσος, romanized: abyssos), meaning "bottomless". At depths of 4,000–6,000 m (13,000–20,000 ft), this zone remains in perpetual darkness.

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