3-D P-velocity structure of the upper mantle of the East Mediterranean
© Geyko V.S., Bugayenko, L.A. Shumlyanskaya,
L.N. Zayets, T.A. Tsvetkova
The paper presents 3-D P-velocity structure of the upper mantle beneath East Mediterranean region. The Taylor approximation of seismic tomography problem developed by V. S. Geyko have been used. The dipping is delineated of the high-velocity mantle layer in the NE of the African plate under Hellenic arc (Aegean micro-plate) to the depth of 350 km to the North-Aegean trough. Dipping of the high-velocity mantle layer of the Sinai sub-plate under the Cyprian arc is shown from the depth of 85 km to the depth of 300 km. The dipping is registered of the high-velocity mantle layer of the Adriatic plate under Hellenides and Dinarides to the depth of 150 km to the Serbo-Macedonian Massif. Correlation has been revealed between the dipping of the high-velocities mantle layers African plate under low-velocities mantle layers of the Alpine mobile belt with deep earthquakes and surface earthquakes. The NE part of the African platform has a high-velocity layer at the depth of 50-350 km and a low-velocity layer at the depth of 350-650 km with two minimums of 400 and 600 km. The Sinai sub-plate is mapped between the African plate, the Arabian plate and the Anatolian micro-plate. The Sinai sub-plate is characterized by alternation of low-velocity and high-velocity layers with depth. Special feature in the Alpine mobile belt is presence of a low-velocity layer to the depth of 250-300 km and high-velocity layer to the depth of 600-650 km. High-velocity zone of the north-western strike is registered at the depth 100-150 km under the Sinai sub-plate, the Mediterranean sea (including the Crete island area in the north and the Libyan trough and the South-Lebantine depression in the south), and the Adriatic plate, which divides the Mediterranean area into two parts: the Western and the Eastern ones and stretching to the Hercynides of the Saxo-Turingian zone.