Otto de Grecia

or plan of Wadati-Benioff

The Plan of Wadati-Benioff is the more or less complex surface formed by the distribution of the Hypocentre S of the Séisme S associated with a Subduction.

This short definition can seem strange. Indeed, the plan of Benioff is defined by describing the effects of the phenomenon of subduction, rather than its cause. It is important thus to recall that the first observation is made by Kiyoo Wadati Central Meteorological Observatory in 1935 and that the more systematic study of this particular distribution of the seismicity by Hugo Benioff date of 1949. However, the theory of the Plate tectonics , which provides a framework general to explain this phenomenon, appears only during the Sixties.

The most remarkable point of this plan is that it should not exist. Indeed, the earthquakes require a fragile comprising medium to occur. Starting from 50 km of depth, the pressure and the temperature should not allow such a mechanism. However, of the seisms are localized until a depth of approximately 670 km, corresponding to the limit between the higher coat and the lower coat. No observation of seismicity in the subductée plate or Slab was made beyond this limit. The discussion on the mechanisms explaining the existence of major seisms is always of current events like on their type of mechanism. The only current consensus is the existence of a dependence of the mechanism according to the depth.

source

Howell Benjamin (1990). Year introduction to seismological research. History and development. Cambridge University Near. New York. (ISBN 0521385717) .
Stein Steth and Michael Wysession (2002). Year introduction to seismology, earthquakes and earth structure. Blackwell Publishing Ltd. (ISBN 0865420785) .

Random links: