The structure and evolution of the passive continental margins of the Arctic Ocean are considered on the example of the South Kara Basin. Its development is associated with the evolution of the West Siberian Plate and the formation of the Arctic Ocean. Until the Late Cretaceous, the South Kara Basin was the north margin of the West Siberian Plate, whose formation is related to the Permian–Triassic processes of riftogenesis accompanied by the eruptions of traps. In the Mesozoic, due to the opening of the Arctic Ocean, the South Kara basin became a part of the continental margin, where the accumulation of marine sandy–clayey rocks continued.

New structures were revealed in Central Tibet after reinterpretation of the first arrivals of refracted seismic waves along the INDEPTH III profile. The method that was used for travel-time inversion is the numerical generalization of the Herglotz-Wiechert formula for the case of a 2D inhomogeneous medium (the homogeneous-function method). The new section shows that the Bangong-Nujiang Suture (BNS) is a contact in the upper crust, while its continuation in the middle crust is a listric thrust; at the top of the lower crust, which has risen to a 32-km depth in the northern part of the section, this thrust become gentler. Below the middle crust top, a layer with a lower velocity of seismic waves is found. The middle crust is deformed and forms oblique southward listric thrusts. In the upper crust south of the BNS, higher-velocity zones (probable zones of magmatism) are distinguished. North of the BNS, undisturbed outlines of the structures are observed.

On the basis of reflected wave hodographs interpreted by the method of homogeneous functions, the section of the lithosphere across the Caucasus, Caspian Sea and Turan Plate was obtained without the use of any preliminary section model. In a section of more than 1000 km, mantle and crustal structures and junction patterns between them are seen down to 60 km within the limits of the Kura Basin and the South and Middle Caspian basins and the Turan Plate. The section of the South Caspian Basin is generally consistent with the ideas of E.V. Artyushkov concerning its structure. A sedimentary layer of up to 30 km thick is underlain by a thinned crust about 10 km thick and by high-velocity mantle. The Turan Plate consists of three layers, which are typical for cratons that are about 50 km thick.

The data from the deep seismic sounding along the 2100 km long FENNOLORA profile are considered. Interpretation is made by the method of homogeneous functions with the Earth's curvature taken into account. A seismic section of up to 200 km depth is the result. The image of a thick northward-dipping lithospheric slab, which is located beneath the lithosphere in the mantle, is obtained. The data we obtained are compared with the results of other authors.

Regional seismic works in the area of the Norilsk copper-nickel deposit were made using the seismic refraction method in the 1980s. These data were used to derive new information about the studied area. The data of eight profiles of about 2900 km total length were processed by the homogeneous functions method and reinterpreted.

New data on the deep structure of the White Sea have been obtained. An interpretation of traverses 510 km in total length is presented. It has been found that the area of the Black Sea that was surveyed with the traverses is characterized by a consolidated crust consisting of two layers. In the velocity sections, interleaving of horsts and grabens is sharply identified. In the central part of the sea, an isometric trough is found with sediments up to 7–8 km thick. The trough is surrounded by east- and northeast-striking ledges and faults. Rocks with anomalously increased velocities are found in the lower part of the sedimentary cover. The thickness of the upper crust is 5–7 km. The lower crust is of a complicated structure and is 30 km thick; it forms a large fold surrounded by rocks with decreased velocitys.

Geological interpretation of seismic sections calculated using modern methods of processing data of deep seismic sounding of the 1960s was carried out. Images and quantitative characteristics of rift structures around Andrusov ridge and elements of the subduction zone in the southern frame of the Skiff plate were obtained. The location of structures in plan was determined.

In the MSU reinterpretation of mid-scale geophysical data was done and new tectonic scheme of the territory was suggested. Discussing the nature of anomalous potential fields both deep-seismic data DSS, CRM, CDP method new tectonic conceptions about rotation causes of occurrence of the global cataclysms on the Earth and the tectonic forces operating in the initial stage of these cataclysms were attracted. All of these have given a basis for new estimating of dynamic life of breaks in areas, where the ancient Siberian platform joints with young West-Siberian plate and to the north – with mobile almost width-spread Enisey- Khatangskaja zone. So the main perspectives on search of ore and hydrocarbon fields in the region are deal with these through-crust break zones, which were the areas of discharge of deep fluids during Phanerozoe.

The paper discusses the mantle structure along superlong seismic profiles in Russia examined using the method of homogenous functions. Two-dimensional heterogeneous sections of the upper mantle were calculated from travel-time curves to a depth of 500–600 km with allowance for the Earth’s curvature without using any a priory information. The presentation of sections as surfaces with a shaded relief combined with velocity contours allowed discerning the principal interfaces in the lithosphere and in the upper mantle, the internal structure of layers, and local heterogeneities of different shapes (convective cells and slabs) in the sections.

Presented below is a method of the inversion of refraction seismic data. The presentation compares interpretation of refraction data by homogeneous function method with CDP reflection depth section for the same profiles. We show that the method of homogen

This paper discusses the results of interpreting seismic profiles on the Earth’s crust of the Maritime Territory and Sea of Japan performed during the 20th century by the Sakhalin Integrated Research Institute and by the Schmidt Joint Institute of Physics of the Earth, Russian Academy of Sciences. The seismic profiles confirmed the presence of structural features under the Maritime Territory and the Sea of Japan that were revealed previously from geological data, such as spreading zones, rifts, deep-seated faults, overthrusts, and subduction zones, suggesting an active type of continental margin in the Far East region. We assumed that a high occurrence of the asthenospheric layer enclosing magmatic chambers explains the high activity of tectonic processes in the Far Eastern continental margin. The identified system of rifts and spreading centers supports this assumption.

New processing and new interpretation of the refraction data of 8 long profiles is made. The profiles form an almost uniform grid with a step 50-70 km in region located in area of Norilsk. The profiles, executed per 80 years, cross Yenisei River and Pyasina, Lama, Keta, Khantayskoe, Dyupkun, Severnoe lakes. The traveltime curves has been reinterpreted by a method of homogeneous functions. The obtained sections by depth till 10-20 km include interfaces and map an internal structure of the layers, give a location of steep and gentle faults. Two thick high-velocity layered and folded strata, presumably of Proterozoic age, cover blocks of the crystal base. The continuous representation of new sections has allowed constructing velocity horizontal maps - slices, which give a location of geological structures in space. The location of the large structures, allocated per in the past years, is confirmed. These are the Khantaysko-Rybinsk megaswell and the Dolgansk depression. Besides on the velocity map-slices and the cross sections the image of a series of rift structures is obtained, whose location close coincides with a location of large lakes in region.

[1] In the frame of the international project “InterMARGINS”, the research in the deep structure of active continental margins of the transition zone from the Eurasian continent to the Pacific was conducted along the deep cross-section of the tectonosphere including the lithosphere and the asthenosphere. The deep section profile runs across the Mesozoic structures of Sikhote Alin, rift structure of Tatar Strait, Cenozoic formations of Sakhalin, Kuril Basin of the Sea of Okhotsk, volcanic structures of Kuril Island Arc, Kuril deep trench and the Mesozoic plate of Northwest Pacific Basin. The length of the profile is 2000 km. The depth of penetration into the earth’s interior is 100 km. A distinctive feature of the transition zone structure is the asthenospheric layer occurrence in the upper mantle; diapirs of hot anomalous mantle branch off from this layer and processes going on in them cause the formation of the region geological structures. A correlation is noted between geological structures, tectonic and magmatic activity and the upper mantle structure. Tectonically active regions like island arcs and rift structures of marginal seas correspond to thick and most distinct asthenosphere generating magma.

In 1995–1998 and 2003–2005, detailed deep seismic soundings were undertaken in the Barents-Kara Region along geotraverses 1-AR, 2-AR, 3-AR with a total length of over 3000 km. Seismic cross-sections, up to 50 km deep as an average, were obtained using the software package GODOGRAPH designed at the Department of Seismometry and Geoacoustics of the Lomonosov Moscow State University. The study was based on refraction traveltime curves with approximately 100 curves per profile. The sections obtained along the 1-AR and 2-AR traverses were geologically interpreted. The main crustal boundaries, fold-thrust structural features of the lower crust and a suture zone between the North Barents Basin and the Caledonian Orogenic Belt were distinguished. Based on our data, the structure of the suture can be interpreted as an ancient subduction zone. The possible pattern of tectonic movements of the Barents Plate is characterized.

In 1995-1998 seismic investigations were carried out along the regional lines 1-AR and 2-AR in Barents-Kara region. The length of each geotraverse was about 1000 km. Seismic cross sections along these lines were obtained with depth more 50 km. These cross sections were computed using the program GODOGRAF, developed in Moscow State University and based on method of homogeneous functions. As a result of interpretation of these cross sections rift structures in Barents basin, infolded structures in the lower crust and deep commissure between North-Barents Basin and Caledonian orogene of the West Barents region were described. Also the possible tectonic movements in the region were defined.

Seismogeologic sections for the Barents-Kara region along geotraverses 1-AR, 2-AR, and 3-AR with a total length of about 4000 km were obtained using the GODOGRAF software package developed at the Department of Seismometry and Geoacoustics of the Moscow State University. The data were travel times of refracted waves excited by approximately 100 sources along each traverse. This paper reports sections for the 3-AR traverse covering areas of the White Sea, Pechora Sea, and Kara Sea, and a geological interpretation of these. The sections cover depths down to 40–50 km and show basic crustal discontinuities, fold-thrust, rift, and paleospreading structural features, and paleosubduction zones. We characterize the possible character of the junction between the South Kara and North Kara basins. A geodynamic interpretation of the structures is provided for the Barents-Kara region.