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We study motions of a light spacecraft equipped with a solar sail near a heavy gravitationally stabilized heliocentric space station. We claim that in this situation the spacecraft relative motion is caused by the solar radiation pressure mainly. Moreover, we find out that if the spacecraft motion is somehow restricted by tether(s) then this pressure can produce acceleration directed at an obtuse angle to the sunlight rays. We suggest some algorithms of selection of the solar sail orientation to provide the spacecraft motion along trajectories realized by the tether(s) in the orbital frame of references. Particularly, we construct the diagram of the sail optimal orientation for motions along a given trajectory in both directions. Also, we establish that if the spacecraft is joined with the station by one tether then a number of the spacecraft motions can be considered as small perturbations of the spherical pendulum motions, in particular, of conic motions.

Motions of a spacecraft equipped with a solar sail and tethered to a heliocentric station is considered. The problems of the spacecraft motion along plane sections of a sphere, restricting its motion with respect to the station, are studied as analogs of perturbed librations of a spherical pendulum or as some generalizations of them.

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.

In this paper, we study relative motions of a light spacecraft equipped with a solar sail and tethered somehow to a heavy heliocentric orbital space station. One can say that such spacecraft realizes a kind of a coastal navigation. Formulating a model problem of the spacecraft motion, we state that if the sail can be oriented arbitrary then motions along a rectilinear tether are possible in both directions. Also, we present algorithm of the spacecraft relocation if it is joined with the station by a tether. This algorithm is based on the motion equations solutions that can be interpreted as perturbed motions of a simple pendulum.

We study dynamics of a particle moving along a gantline with ends fixed on endpoints of an extended space station which mass center describes a circular orbit in the central Newtonian force field. We restrict to the case of gravitationally oriented station, in other words, we suppose that the station is directed on the attracting center throughout the motion. Assuming that the gantline is weightless and unstretchable tether that realizes unilateral constraint, we establish that spacial motions of the particle are librations near the orbit plane generally. Such librations might be regular, including periodic ones, or chaotic. We note that, in general case, the gantline remains taut all the time for regular motions only.

The Caucasian-Arabian belt is part of the huge late Cenozoic Alpine-Himalayan orogenic belt formed by collision of continental plates. The belt consists of two domains: the Caucasian-Arabian Syntaxis (CAS) in the south and the EW-striking Greater Caucasus in the north. The CAS marks a zone of the indentation of the Arabian plate into the southern East European Craton. The Greater Caucasus Range is located in the south of the Eurasian plate; it was tectonically uplifted along the Main Caucasian Fault (MCF), which is, in turn, a part of a megafault extended over a great distance from the Kopetdag Mts. to the Tornquist-Teisseyre Trans-European Suture Zone. The Caucasus Mts. are bounded by the Black Sea from the west and by the Caspian Sea from the east. The SN-striking CAS is characterized by a large geophysical isostatic anomaly suggesting presence of mantle plume head. A 500 km long belt of late Cenozoic volcanism in the CAS extends from the eastern Anatolia to the Lesser and Greater Caucasus ranges. This belt hosts two different types of volcanic rocks: (1) plume-type intraplate basaltic plateaus and (2) suprasubduction-type calc-alkaline and shoshonite-latite volcanic rocks. As the CAS lacks signatures of subduction zones and is characterized by relatively shallow earthquakes (50–60 km), we suggest that the “suprasubduction-type” magmas were derived by interaction between mantle plume head and crustal material. Those hybrid melts were originated under conditions of collision-related deformation. During the late Cenozoic, the width of the CAS reduced to ca. 400 km due to tectonic “diffluence” of crustal material provided by the continuing Arabia-Eurasia collision.

The deep structure of the Sea of Okhotsk under seismically dangerous regions is studied. The main feature of the deep structure in the region is the occurrence of an asthenospheric layer in the upper mantle. Asthenospheric diapirs can effectively rise through the crust, causing destruction of the lithosphere, formation of deep basins, faults and rifts accompanied by shallow-focus earthquakes, and eruptions of volcanoes. The vast majority of earthquakes are confined to the Kuril Island Arc, where the Pacific Plate is subducted under the continent. The seismicity in the region is a result of active tectonics in the subduction zone. This zone is traced to a depth of 700 km. In the west, the Okhotsk Sea Region is bounded by the deep faults extending along Sakhalin, where earthquakes are localized in the crust. The ancient subduction zone under Sakhalin is established. In the late Cretaceous to Paleogene the subduction of the Okhotsk Sea Plate under Sakhalin ceased. The reactivation of this ancient subduction zone may currently be in response to the strong earthquakes in Sakhalin.

The northern part of Sakhalin Island is an area of recent intensive tectonic movements and hydrothermal processes, as well as a place of accumulation of useful minerals. The deep structure of the lithosphere beneath the region of the Neftegorsk earthquake of May 27, 1995 in North Sakhalin, which killed residents and caused significant destruction, is examined in this paper. Our geodynamic model shows that North Sakhalin consists of the North Sakhalin Basin, Deryugin Basin and an ophiolite complex located between them. The Deryugin Basin was formed in place of an ancient deep trench after subducting the Okhotsk Sea Plate under Sakhalin in the Late Cretaceous–Paleogene. The North Sakhalin Basin was formed on the side of the back-arc basin at that time. The ophiolite complex is fixed in the position of ancient subduction zone that was active in the Late Cretaceous–Paleogene. Approximately in the Miocene, the subduction of the Okhotsk lithosphere apparently ceased. The remains of the subduction zone in the form of an ophiolite complex have been identified from geological and geophysical data. On the surface, the subduction zone is manifested as deep faults stretched along Sakhalin. It is probable that the Neftegorsk earthquake was a result of activation of this ancient subduction zone.

The Russian World Data Center for Solar-Terrestrial Physics and the World Data Center for Solid Earth Physics have been collecting, analyzing, archiving, and disseminating data and information on a wide range of geophysical disciplines since the International Geophysical Year 1957-1958. The centers provide free and convenient access for users to their large and permanently increasing volumes of data. Russian WDCs participate in scientific national and international programs and projects, such as InterMAGNET, InterMARGINS, and the International Polar Year. Since 2008 there has been an association of five Russian WDCs and one Ukrainian WDC in a regional segment of the World Data Centers.

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.