6 research outputs found
Parameters of the fault planes for the Crimean Black Sea region by averaged mechanism of close earthquakes
A modern field of stress of the Crimean Black Sea region was constructed. A method of averaged mechanisms was used to construct the field of stress, which uses the earthquakes of varying intensity, including weak ones that prevail in the region. The research allowed allocating 15 blocks in the areas with different pairs of forces compression-stretching. It has been shown that nodal plane, formed under the influence of these forces describes the planes of rupture of tectonically active faults. Types of movements within the faults, which occur in the Crimean Black Sea region, were found. It has been shown that the faults and types of movements along them are related to the relief of Moho surface, and subcrustal mantle is a source of movement into the faults. Non-double-dipole model of the source of stresses was used to solve averaged mechanism. It makes possible to show that the Yalta-Alushta seismo-focal zone was formed by rotating the surrounding blocks counterclockwise. The axis of rotation corresponds to cross-section of the Salgir-Oktyabr’ and Orehovo-Pavlograd faults
Three-dimensional P-velocity model of the upper mantle of the Western Mediterranean
The paper presents 3D P-velocity structure of the upper mantle beneath Western Mediterranean region. Taylor approximation of eikonal equation and wave equation proposed by V. S. Gey-ko have been used. Influence on the velocities structure of the mantle under Western Mediterranean of oblique layers, spreading at different depths from the South (African platform), the West (Atlantic) and the East (Adriatic micro-plate) has been revealed
Seismotomography of the East European platform: a three-dimensional P-velocity model of the mantle near Fennoscandia. Part II
This paper is an extension of a set of works on seismic tomography of East European platform. A velocity pattern given corresponds to the mantle under Fenno-Scandian shield as a northwestern part of EEP. The main velocity characteristics of the mantle under the Fennoscandia, conformed along vertical and horizontal sections is common inverse property of velocity structure of the mantle. The mantle under the main part of Fennoscandia is subdivided into three groups according to its velocity characteristics. To the first group belongs the mantle under Karelian, Belomorian and Central Kola + Murmansk blocks of the Kola-Karelian mega-block, Baltic mantle block and Svekofennian block-1. To the second one belongs the under Lapland-Belomorian belt-2, Svecofennian block-2, Sveconorvegian megablock. The third group comprises the mantle areas under the Baltic block, Svecofennian block 1, Laplandian-Belomorian belt-1, which belong to transitional ones between the first and the second groups.The main borders of mantle divisibility under Fennoscandia are coordinated by both horizontal and vertical sections. They are determined by common velocity mantle characteristics, such as divisibility of the mantle according to velocity characteristics of horizontal sections, special features of velocity distribution such as presence of sub-horizontal high-velocity inclined layers, which spread from the layer of seismic lithosphere into the layer of Golitsyn-Geiko. High-velocity inclined layers separate the mantle area under Trans-Scandinavian magmatic zone and, within the limits of the mantle under Kola-Karelian mega-block, the area of distribution of mantle effects under the North Atlantics eastward
Seismotomography of the East European and Barents Pechora platforms: a three-dimensional P-velocity model of the mantle near the Volga-Uralia, the Caspian Basin and the Barents-Pechora Platform
The article is an extension of the set of papers on seismic tomography of the mantle under the East-European platform (EEP). Three-dimensional P-velocity model of the mantle under the EEP and the Barents-Pechora platform (BPP) is considered in the context of three-dimensional P- velocity model of the mantle under Eurasia. According to velocity characteristics at the depth of 50-500 km the mantle under EEP is integrated with the mantle under BPP. In the layer of seismic lithosphere the mantle under the integrated area of EEP and BPP is specific by high velocities as well as the mantle under the whole territory of the Northern Eurasia except the southern half of the Siberian platform. Velocity characteristics of the mantle under the eastern part of integrated area of EEP + BPP is influenced by mantle velocity area under the West-Siberian platform