hadal

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hadal

[′hād·əl]
(oceanography)
Pertaining to the environment of the ocean trenches, over 4 miles (6.5 kilometers) in depth.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Nonetheless, the current testing setup will have to do for now since the hadal zone still has unmapped areas.
The main purpose of this paper is to further advance geochemical studies in the hadal zone by using time-series observations and the first measurement of [sup.222]Rn above the trench bottom.
In contrast, silicate profiles in the hadal zone (Fig.
2a) in the hadal zone showed a slightly increasing trend with depth at both AN1 and LM2.
The higher and lower values of potential temperature and dissolved oxygen, respectively, at ~6000 m depth over the hadal zone were supported by the CLIVAR and GO-SHIP data gathered across the Izu-Ogasawara Trench between 142.3[degrees]E and 144.3[degrees]E along the 30[degrees]N line.
"The hadal zone extends from around six kilometers to the deepest seafloor.
Detritus-eaters are mainly represented by amphipods (lissianassids), polychaetes, brittle-stars, and fish, but only amphipods go down to the hadal zone.
The normal biomass values found on the abyssal plains range from 0.1-5 g fresh weight per square meter, while at the greatest depths of the hadal zone they are often less than 0.03 g.
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]).
Since the retirement of the Trieste and the French bathyscaphe Archimede in the early 1960s, no nation has had the capability to dive much below 10,000 feet (6000 meters) into the unexplored hadal zone, located pormarily in the deep canyons winding around the Pacific Rim and into the Indian Ocean and the Caribbean Sea.
The hadal zone is the name given to the deepest depths of the ocean, named after hades as the underworld god of Greek mythology.
The prints represent both scientific data, rarely seen images of geothermal activity in the abyssal and hadal zones, and formal compositions, elegant black-and-white abstractions.