Simultaneous inversion of P wave arrivals of 262 local earthquakes, recorded in the region of the Dead Sea, was carried out to model the velocity stratification in the underlying crust and uppermost mantle. The resulting tomographic model delineates several large magmatic domes, rising from the lower crust, at depth of approximately 20 km, and ascending more than 12 km into the overlying intermediate crust. Commonly, the domal ascent took place along the boundary faults of the Dead Sea rift. The domes are elliptical in shape, measuring nearly 5 × 15 km in diameter, and are spaced about 20 km apart. Earthquake foci are abundant around the diapirs but rare within them. The occurrence of these magmatic diapirs under the Dead Sea implies anomalously high temperatures with metastable stratification in the lower crust and suggests magmatic upwelling.
http://www.agu.org/pubs/crossref/1996/95TC03497.shtml
http://www.agu.org/pubs/crossref/1996/95TC03497.shtml
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