The
abyssal zone is the abyssopelagic layer or
pelagic zone. "Abyss" derives from the
Greek word ἄάβυσσος, meaning bottomless. At depths of 4,000 to 6,000 metres (13,123 to 19,685 feet), this zone remains in perpetual darkness and never receives daylight. These regions are also characterised by continuous cold and lack of nutrients.The abyssal zone has temperatures around 2 °C to 3 °C (35 °F to 37 °F) through the large majority of its mass. It is the deeper part of the
midnight zone which starts in the
bathypelagic waters above. Its permanent inhabitants (for example,
Riftia pachyptila, (the
Giant tube worm) found near
hydrothermal vents in the
pacific ocean and the
giant squid are able to withstand the immense pressures of the ocean depths, up to .