2014 , Volume 19, № 5, p.101-114

The present study addresses convection beneath the continental lithosphere. The target area is bounded by a spherical region of the upper mantle (i. e., by the phase boundary, down to the depth of 670-700 km) from the zero meridian to eastern boundaries of Eurasia (145° E) and from the equator to northern boundaries of the continent (80° N). This large region includes several continental platforms as investigated objects, which are not homogeneous in their age and thickness. During the calculating for Eurasian continent, it becomes necessary to take into account the influence of sphericity. The area of our investigation includes the Siberian craton and its surrounding territory: West Siberian, East European and Chinese plates, Tarim, a complex of Tuva-Mongolian micro plates, Central Asia folded zone, and a segment of the Indian Plate. We constructed a threedimensional numerical model of thermal convection based on Navier - Stokes equations in the geodynamic approach, in spherical variables using the artificial compressibility method. We were interested in determination of the influence of the craton geometry on the structure of mantle flows beneath the continental lithosphere. The calculation results illustrate the structure of convective flows. We also have constructed the numerical model for oceanic plate, which immersed under continental plate. The results of computations agree with geophysical understanding on the process of subduction.