Three-dimensional P-velocity model of the Black Sea and adjacent area mantle
© Bugałenko I.V., Shumlyanska L.A., Zaiets L.N., Tsvetkova T A.
Three-dimensional P-velocity model has been plotted of the Black Sea and its surrounding up to the depth of 2500 km with the help of Taylor approximation method of solution the problem of seismic tomography proposed by V.S. Geyko. The analysis has been conducted for the Black Sea region of velocity characteristics of the upper mantle, the zone of division-I, the middle mantle, the zone of division-II and the upper parts of the lower mantle. Low-velocity anomaly has been distinguished at the depth 2500-1500 km in the area integrating the Andrusov uplift, the Arkhangelskiy uplift, the Synopian trough and the eastern extremity of the West Black Sea depression. Low-velocity upper mantle under the Black Sea is subdivided into two parts corresponding to West Black Sea and East Black Sea depressions by the subdivision area corresponding to the mantle under the Central Black Sea uplift and the eastern margin of the West Black Sea depression. The velocity characteristics of the upper mantle of the West black Sea depression is influenced the most considerably by the low-velocity structures of the Carpathian-Balkan region (from the east) and the Anatolian micro-plate (from the south). The velocity characteristics of the upper mantle of the West black Sea depression is influenced the most considerably by the low-velocity structures of the Anatolian micro-plate (from the south) and the high-velocity layers extending with a pitch from the Turanian plate (on the east). The special feature of the velocity structure of the upper mantle of the East Black Sea depression is displayed in subdivision of high-velocity layers extending with inclination from the Turanian plate up to the Central Black Sea uplift (from the east). In the Black Sea region and its surrounding high-velocity inclined layers have bees distinguished extending from the side of the Turanian plate and the East Europea platform. The extention of high-velocity transitional zone of the mantle of the Anatolian plate under the Black Sea and further to the north under the Dnieper-Donets depression and the Donbas is observed from the south. According to its velocity characteristics of the mantle the Black Sea region is a complicated knot of tripple jointing of the structures of the East European platform, the Alpine mobile belt and the Scythian-Turanian platform.