The abyssal zone occupies the centers of the oceans with depths of 9,843-19,685 ft (3,000-6,000 m).
The benthic fauna is better-known because organisms are "concentrated" on the seafloor and capturing them is relatively more efficient; it occurs in the bathyal zone (between 656 and 13,123 ft [200 and 4,000 m] depth, immediately below the sublittoral zone occupying the entire continental platform), the abyssal zone (between 13,123 and 19,685 ft [4,000 and 6,000 m]) and the hadal zone (between 19,685 and 36,089 ft [6,000 and 11,000 m]).
If debris is found between 2,000-6,000 meters - known as the abyssal zone
- salvagers would work in a perpetually dark and near-freezing region where the pressure can reach up to 9,000 pounds per square inch (psi).
Several authors have discussed zoogeographic and diversity patterns for Brazilian shallow waters based on benthic invertebrates (e.g., Briggs, 1974; Semenov, 1978; Kempf, 1979; Palacio, 1982; Floeter & SoaresGomes, 1999), but few have discussed biogeographic patterns of the neighbouring slope or abyssal zones
(Allen & Sanders, 1996 is a good example for abyssal basins).