Deep-sea Trenches

Trenches, Deep-sea

 

one of the most characteristic elements of the relief of the transitional zone between a continent and the ocean, consisting in a long, narrow lowering in the ocean floor to a depth of over 6,000 m. Deep-sea trenches are usually located on the outer (ocean) side of the mountain ranges of the island arcs. Geologically they represent contemporary geosynclinal structures. The deepest trenches, such as the Marianas Trench, reaching a depth of 11,022 m, are found in the Pacific Ocean.

References in periodicals archive ?
The next stage for the team is to quantify their results and work out exactly how much more carbon is stored in deep-sea trenches compared with other parts of the sea, and how much carbon turnover by bacteria is being carried out.
These mash-ups create deep-sea trenches, like the Mariana.
The deepest parts of the ocean are deep-sea trenches. These are generally off the continental shelves and plunge as much as 11 kilometres.
Scientists today recognize distinct assemblages of animal species in six major seafloor regions (colored dots) along the system of volcanic mountains and deep-sea trenches that form the borders of Earth's tectonic plates.
At deep-sea trenches, the ocean crust plunged deep into the Earth's mantle triggering major earthquakes.
These plates converge at deep-sea trenches, plate boundaries where one plate sinks (subducts) below the other at so-called subduction zones.
Deep-sea trenches, which are subject to frequent catastrophic sediment slumping, have relatively low diversities.
(See Oceanus Winter 1992/93 for a discussion of "Island Arcs, Deep-Sea Trenches, and Back-Arc Basins.) Ocean drilling has provided fundamental information about colliding-plate processes, including accretion of sediments and volcanic edifices from underthrusting to overriding plates, emplacement of rocks that have been altered by the forces at work in colliding-plate zones, and the nature of continental collisions.
Chains of volcanoes, deep-sea trenches, and back-arc basins festoon the western Pacific rim from the Aleutian Islands to Indonesia to New Zealand.