Abyssal zone

Abyssal (from the Greek ἄβυσσος Abyss - gratuitous depth, the abyss; according to early ideas of the ocean no land owned ) is according to the majority opinion in the research of part of the sea floor ( marine benthic zone ) between 2,000 m and 6,000 m water depth, but sometimes also the entire deepwater understood below.

Geology

This depth is in the morphology of the seabed of the area of the continental shelf and the deep sea to seaward adjoining panels, and the basaltic mid-ocean ridges; occupies an area of almost 60 % ( 58.3 %) of the earth's surface. In coastal regions, the area of the continental foot are the sediments deposited by appropriately terrigenous character, because the continental slopes covering clastic sediment masses come off in the form of huge submarine landslides and turbidity currents of the mighty flanks of the continent and can cover large areas of the sea floor. In the sea, the sediments then take to a pelagic character. Below the calcite compensation depth (CCD, also Lysokline ) at about 5,000 m is almost all lime, the less soluble Kalzitform disappeared. The seabed consists mainly of seemingly endless here, monotonous red to chocolate brown Tiefseeton.

Biology

The Abyssal is lightless and therefore no plant life. This habitat characterized by cold and constant conditions ( habitat ) is colonized by benthic sponges, coelenterates, worms, crustaceans and echinoderms.

On the edge of the mid-ocean ridge hydrothermal vents are found with so-called black smokers ( black smokers ), White Smokers and Hot Vents with a highly specialized fauna, which draws its energy from the rising sulfur compounds.