Wadati–Benioff zone

Wadati - Benioff zones ( usually called Benioff zones in the older literature ) are formed by the subducting plate at a subduction. They are characterized by deeper -reaching hypocenters of earthquakes. The discovery of these zones was a further indication of the theory of plate tectonics. They were discovered each other named independently of the U.S. seismologists, Hugo Benioff and his Japanese colleague Kiyoo Wadati and later to them.

In Wadati - Benioff zone earthquake foci to be detected at 700 km depth, where the ovens are placed on an inclined surface. The earthquake epicenters are distinguished according to the position of sinking into the mantle, subducted tectonic plate. This in contrast to the relatively cool upper mantle material of the subducting plate preserved for a long time its ability to reduce the costs of their subduction stresses in rocks by brittle fracture, which shows up in every time an earthquake event.

Another feature of Wadati - Benioff zones is the anomaly of the geothermal gradient. Due to the slow warming rocks of the subducting plate occur at lower temperatures than would be expected for the mantle for these depths because of the proximity.

Wadati - Benioff zones occur anywhere on where subduction zones are formed near the Kuril shown for example on the west coast of America and around the Pacific. The earthquake zones are there in accordance with the Subduktionsrichtung - the oceanic crust of the Pacific Ocean is the lower plate is subducted and - from the ocean to the continent inclined or submerge under an island arc.