TENSION AND COMPRESSION STRUCTURES IN THE ARTICULATION ZONE OF THE SOUTHERN URALS AND THE EAST EUROPEAN PLATFORM

In recent years, the structure of the southern Urals and the Ural fore deep and the neighboring slope of the East European platform along a l ine between Sterlitamak and Magnitogorsk have been investigated with r egional seismic profiling (common-depth point) to depths of about 20 k m. Steep plunging of the surface of the basement from a depth of 12-13 km on the boundary with slope of the platform to 19 km on the boundar y with the Urals has been established in the Ural foredeep. This surfa ce represents the western flank of the ancient Ural sedimentary basin, which in the Riphean transgressed westward in conjunction with pericr atonic subsidence of the East European platform. Extensive development of extensional dislocations synchronous with the development of the H ercynian imbricate folded structure of the neighboring zone of the Ura ls has been found in the cover of the Ural foredeep and the slope of t he platform. The possible mechanism of joint development of these disl ocations is considered.