PROPERTIES OF THE LITHOSPHERE IN COLLISIONAL BELTS IN THE MEDITERRANEAN - A REVIEW

A brief review of the lithosphere-asthenosphere properties is given for the Mediterranean area. The strongest lateral heterogeneities are found in the proximity of tectonically active areas, such as collisional belts. High S-wave velocities below about 70 km denote the presence of deep-seated, almost aseismic, lithospheric roots under the Western Alps, the North-Central Apennines and the Cordillera Betica. An alternative explanation of the data related to mechanisms of intermediate and deep-focus earthquakes in the Tyrrhenian Sea and Aegean Sea is discussed in the frame of the dynamic subduction model proposed by Freund et al. (1980), which postulates that the slab is disrupted in blocks and pulled down gravitationally. © 1990.