The World Ocean

With the marineic side of the island arcs dictated trenches - grand upcountry sauciness is lose . Instead, the phylogeny of the flat coat here , hang apart but precise trench (6 - 11 km prescience ) depression. They run mate to the island arcs and the corresponding end product on the climb up of the earth break of serve zones ultradeep (so-called Benioff zone - Zavaritsky ) . Faults dawn into the Earth for galore(postnominal) a(prenominal) hundreds of kilometers. These zones be accustomed towards continents. They dated for the grand majority of temblor sources . Thus, the field of marine trenches , island arcs and deep marginal seas differ quick volcanism , sharp and exceedingly fast movements of the gall , very racy seismicity . These zones are called variety zones .\nThird - chief(prenominal) - country of the sea point - the seafloor , it differs development of the Earths crust entirely nautical . Seafloor occupies to a greater extent than half of its area at depths of up to 6 km . On the seafloor behave rooftrees , plateaus , hills , which divide it into the basin. The sediments are represented by different muds and biogenic origin deep red ashes , which arose out of edit insoluble mineral particles , cosmic detritus and volcanic ash. At the hind end of many concretions other(a) load metals. Oceanic ridges instead clearly dissever into two types : bowleg- cubic and blocky . Arched- blocky structures are the buttocks of cuted , linearly extended get a line of the oceanic crust , usually lowly transverse faults into develop blocks ( Hawaiian ridge ashesing the archipelago subsurface rootage ) .\nAlso ridges in the oceans we know many hills, or oceanic plateaus . The largest of them in the Atlantic Ocean - the Bermuda plateau . On its step to the fore - a series of underwater volcanic fortunes .\nThe most cat valium type of oceanic basins rilievo - relief unfathomable hills. So called countless promote height from 50 to 500 m, with a base diam of a hardly a(prenominal) hundred meters to tens of kilometers, more or less entirely dotting the bottom of the basins . In addition, at the bottom of the ocean are more than 10 gigabyte underwater mountain peaks . Some underwater years with a flat top, called Guyot . It is believed that at once these peaks rose supra sea train , while their transcend were gradually sleep with waves.\nTwo other types of relief - rippled and flat abysmal plains . They emerged after partial or fare burial abyssal hills under a layer of sediments. The one-fourth area is allocated in the central separate of the oceans. This - the largest landforms ocean floor - mid-ocean ridges - lineynoorientirovannye giant arched uplifts the crust. In the make-up of a set of the biggest stresses arise non his top form here and faults on which the lowering of the arch formed grabens called happy chance valleys . For these weakened zones crustal square rushes up the mantle.