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The difficulties and contradictions of the classical concept of plate tectonics are discussed. It was shown the postulate of rigid plates and Euler’s theorem on the motion of rigid body with one fixed point, which is the basis of the kinematic description of plate tectonics, cannot be universally applied, e.g., to the analysis of Cretaceous reconstructions of the North Atlantic and Arctic. The second postulate of the existence of lithosphere as separate and distinct tectonic plates, which is equivalent to the assumption on the continuity of all plate boundaries, is not satisfied. This study provides a generalization of the theory of classical plate tectonics, in which plates are treated as deformable bodies, the concept of deformable plate tectonics. The study also discusses a new regional geodynamic model for the Cretaceous and Cenozoic evolution of lithosphere beneath Arctic and Northeastern Asia. The model is based on the assumption of a laterally extended convection cell in the upper mantle driven by a conveyor-belt-like process of subduction of the Pacific plate. The proposed model provides a physically sound explanation for the standard tectonomagmatic processes, such as island arc roll-back and opening of back-arc basins, formation of continental rift zones and igneous provinces at great distances (over 1000 km) from subduction zones, etc.

In this study we present a detailed analysis of natural stresses in the Northern Tien Shan crust averaged in a window of 10-15 km obtained from seismological data of the local KNET network. The transformation of focal mechanism data into the parameters of the stress tensor was based on the method of cataclastic analysis of rupture dislocations elaborated by Yu.L. Rebetsky (Institute of Physic of the Earth, Moscow). The results, including the orientation of the principal stress axes and the reduced stresses, are presented for four depth layers. It was shown that the central part of the study area is dominated by horizontal compression, while multiple domains characterized by horizontal shear and superimposed compression or pure horizontal shear are also present (uppermost layers in the eastern part of the Chuya depression, Suusamyr depression and adjoining regions, in the central part of the Kyrgyz Range). There are also several large domains of high and low effective confining pressure, which defines the corresponding deviator stress, according to the Coulomb-Mohr law. It was shown that relatively strong earthquakes are correlated with zones with low levels of effective pressure where the ruptures are characterized by lower resistance to brittle fracturing, i.e., Coulomb friction stresses. It was also shown that a distinct segment of the ~60 km E-W striking fault on the northern slope of the Kyrgyz Range generates a uniform distribution of stresses, corresponding to a dextral slip along of its edges.

Dynamometamorphic lithologic transformations of ores and ore-hosting rocks are substantiated by the example of the Tishinka deposit and the upper beds of the Ridder-Sokol’noe deposit in Rudny Altai. The lenticular and lenticular-banded morphology of orebodies in the deposits is due to the in situ redeposition of ore substance in the form of bodies oriented concordantly with the direction of the maximum tangential stresses and, correspondingly, the general strike of the deformation-metamorphic structures. It is shown that dynamometamorphism is not only the structure- and rock-forming factor but also plays a great role in the concentration and localization of ores, favoring the formation of rich ore deposits in zones of intense deformations and structural and geochemical transformations. The age of the main phases of dynamometamorphic impact and the time of formation of the deposit orebodies are estimated. For the Tishinka deposit, it is 294-301 and 279-288 Ma (Early Permian), and for the lenticular orebodies of the upper beds of the Ridder-Sokol’noe deposit, ~307 Ma (Late Carboniferous).

The first Sm-Nd isotope studies of the Carboniferous-Early Cretaceous clastic rocks of the northeastern Siberian Platform have been carried out. Variation in the isotope composition of sediments within this time interval has been determined and interpreted. The high ε_Nd( t ) values for Carboniferous-Permian sediments (from -11 to -2) testify to the large contribution of the products of erosion of island-arc and juvenile complexes localized in the Taimyr-Severnaya Zemlya fold-thrust belt in the Carboniferous. The positive ε_Nd( t ) values for Triassic sandstones suggest erosion of the coeval igneous rocks of the trap association. The Upper Jurassic and, particularly, Cretaceous sediments of the Lena-Anabar depression and Verkhoyansk foreland basin are characterized by extremely negative ε_Nd( t ) values (from -15 to -19), which is evidence for erosion of mature continental crust. The Carboniferous-Triassic complexes of the Verkhoyansk fold-thrust belt, which show higher ε_Nd( t ) values, cannot have been a source of detritus for Cretaceous sandstones. The sediments filling the Verkhoyansk foreland basin accumulated as a result of the decomposition of homogenized distal source rocks with the isotope characteristics of the ancient crust rather than the breakup of the mountain range rising to the east. Salients of the crystalline basement of the Siberian Platform, such as the Aldan Shield, might have been these source provinces.

The thermochronology of the Early Paleozoic collisional and subduction-collisional systems and blue schist complexes of the Central Asian Orogenic Belt has been reconstructed by the proposed method of total isotope dating. The evolution of these geologic structures is divided into short synchronous stages of active thermal events related to large-scale mantle-crustal magmatism, high-pressure/low-temperature and high-temperature/low-pressure metamorphism, and intense tectonic deformations. The plume activity of different intensities, both in intraoceanic and intracontinental environments, is presumed to be the deep mechanism of synchronization.

We report the first data on 40Ar/39Ar dating, trace-element geochemistry, and isotope (Nd, Sr, O) composition of the Belaya Gora gabbro-foidolite-foyaite intrusive massif, one of typical representatives of the alkaline province of the northeastern Kuznetsk Alatau. The established age of rock-forming amphibole, ~401-403 Ma, is taken as the time of the pluton formation in the Early Devonian. The distribution and ratios of LILE and HFSE in the rocks suggest that the intrusion took place in the setting of “superposition” of Devonian mantle plume on the Early Paleozoic accretion-collision complexes. Therefore, the source of magmatic products had a heterogeneous composition as a result of mixing of plume material with the substances of suprasubduction and crustal substrates. The mantle component might have been a PREMA + EM combination, which is confirmed by the parameters of the Nd isotope composition (εNd ( T ) ≈ 3.2-4.6; T Nd(DM) ≈ 0.8 Ga) of alkaline rocks. The effects of crustal contamination are reflected in the high ratios of strontium and oxygen isotopes (87Sr/86Sr) T ≈ 0.7046-0.7054; δ18O ≈ 8.5-9.2‰, SMOW).

The influence of the growth stimulants with differences in active substance and concentrations on seed germination ability and seedlings safety of Scots pine (Pinus silvestris L.), Siberian larch (Larix sibirica Ledeb.), Siberian spruce (Picea obovata Ledeb.) are studied. Studies have shown the reaction specificity of seed processing by growth stimulants. The increased concentration of Obereg stimulant (7 drops / 500 ml of water) result in most significant positive impact on the seed field germination of Scots pine (at 31 % above control). The seedling safety is 30 % higher than the control at the same stimulant concentration. Seed treatment by stimulant Ekogel at concentrations of 20 ml/1 l of water and 30 ml/1 l of water result in increase of seed germination and seedlings safety. The extremely high concentration of Ekogel (40 ml/1 l of water) authentically decreases as seed germination (on 21 %), and the seedlings safety (on 20 %). Ekogel stimulant is the best for seed germination of Siberian spruce, thus having a significant positive effect at all studied concentrations. Extreme concentrations of Heteroauxin (4 g/1 l of water) also had a positive impact on the seed germination and seedling safety (20 and 15 % above the control respectively). Seed treatment of Siberian larch by a Novosil stimulant of high concentration (10 drops/1 l of water) and Obereg stimulant (7 drops / 500 ml water) has led to an increase in seed germination compared to controls at 26 and 25 % respectively. At the same concentrations of growth stimulants the highest seedlings safety (25 and 24 % above the control respectively) was observed. Seed treatment by Ekogel stimulant at a concentration of 10 ml/1 l of water has led to a high seed germination ability and seedling safety. Higher concentrations of Ekogel stimulant (30 ml/1 liter of water and 40 ml/1 l of water) significantly inhibit seed germination and reduce the seedling safety.

We studied the cones of Siberian stone pine (Pinus sibirica Du Tour) at its treeline in the forest tundra ecotone in the Severo-Chuisky Range, the Altai Mountains, Russia. We have registered length, diameter and form of apophysis, the number of sterile and fertile scales in the cones, the number of ovules and the number of seeds, including developed and underdeveloped seeds, and the developed seeds/ovules ratio. The cones and seeds are produced below 2350 m a. s. l under arid conditions (east-south-eastern slope) and below 2390 m a. s. l. under more humid conditions (west-north-western slope). These altitudes are reproductive line of Siberian stone pine. The predominant forms of the cones near this line are cone-like, spherical and cylindrical. Apophyses are mostly tuberous, hook-like and flat. The most (50%) of the sampled cones have the cylindrical form. The number of ovules varied from 84.6 to 102.4 per cone, the number of seeds were from 76.7 to 98.9 per cone, and the developed seeds were 74.5 to 95.7 per cone. The lowest proportion of developed seeds was registered for cones sampled on arid east-south-eastern slope in 2011. The cones with tuberous apophysis have the highest number of seeds (up to 103.6-110 per cone under more humid and 87.3-104.4 per cone under more arid conditions). Cones gathered at 2235-2390 m a. s. l. have low presence of underdeveloped seeds (1.0 to 3.2 %) and high developed seeds/ovules ratio (87.2 to 93.7 %).

The paper reports on new and previously not well-known data on insufficiently studied fauna of aphids living on coniferous trees in Central Siberia of the basin of Yenisei river. This region is the extensive transect of latitudinal geographic zones from semi-desert in the South to the arctic deserts in the North. That is why this region is very peculiar. This is the reason for insufficient study of regional entomological fauna. Aphids (Homoptera: Aphidoidea) are a very taxonomically and ecologically heterogeneous group of insects. The aphids living on conifer trees are not studied completely on the territory of Yenisei basin. Due to this, the studying of not well-known and economically important aphids is actual. For example, the insufficient study of regional aphids is confirmed by the fact, that during three weeks only of the work for INTAS-94-0930 Project two new aphid species were found and described on this territory. Also, the new species of family Mindaridae, which was described in Mongolia in 1980, was found in Siberia for the first time. These finds indicate the real possibility to describe an interesting conifer aphid complex in the absolutely unstudied forested territory between Angara and Lower Tunguska rivers. Geographical location, dates of collection and feeding preferences of different species are described. A general review of Yenisei basin Siberian aphid fauna is suggested for the first time ever.

Based on the results of the long-term investigation, carried out in the Russian Far East (Primorye and Khabarovsk Territories, Amur and Sakhalin regions), and published data about bird ecology, the actual material about the birds feeding seeds and berries of the Amur cork-tree, Phellodendron amurense Rupr. and Sakhalin cork-tree, Ph. sachalinensis (Fr. Schmidt) Sarg., is given in the article. It has been found 43 carpophagous bird species from 15 families and 5 orders. The cork-tree berries, small roundish juicy fruits with little stones, are eaten by the birds of 40 species from 13 families; basically by Grey-headed Woodpecker - Picus canus, Azure-winged Magpies - Cyanopica cyanus, Bohemian and Japanaese Waxwings - Bombycilla garrulus and B. japonica, Thrushes: Pale Thrush - Turdus pallidus, Eyebrowed Thrush - Turdus obscurus, Grey-backed Thrush - T. hortulorum, Naumann’s Thrush - T. naumanni, and Dusky Thrush - T. eunomus, Eurasian Nuthatch - Sitta europaea, Pallas’s Rose Finch - Carpodacus roseus. The secondary birds - 16 species. On the Sakhalin isl. the Sakhalin cork-tree, Ph. sachalinensis berries are eaten by the birds of 33 species from 12 families, on the South Kuriles (Kunashir isl.) - by the birds of 28 species from 11 families. On Sakhalin the berries are eaten basically by the Waxwings (2 species), Dusky and Brown-headed - Turdus chrysolaus - Thrushes, Eurasian Nuthatch, Pallas’s Rose Finch; and secondary birds - 12 species. There are 5 species of the primary birds and 8 species of the secondary birds on the Kunashir isl. A participation of the birds in the dissemination of the cork-tree, Phellodendron Rupr., during seasonal migrations in winter and autumn has been considered. The active birds in the seed distribution are Grey-headed Woodpecker, Azure-winged Magpies, Waxwings, Thrushes and others; while they are eating the berries, the seeds are not damaged in the gastrointestinal tract and pushed with the excrements outside. In addition, Eurasian Nuthatches and Tits actively distribute the seeds, making stocks under the tree bark and in the semihollows. The passive agents of dissemination are Hazel Grouse - Tetrastes bonasia, Common Pheasant - Phasianus colchicus, Great Spotted Woodpeckers - Dendrocopos major, Oriental Tutle Doves - Streptopelia orientalis, Pallas’s Rose Finches, Hawfinches - Coccothraustes coccothraustes and some others, who can crack hard seed peel by the peckers, but some part of the seed peels retain undamaged in the gastrointestinal tract and is pushed outside. The main role in the cork-tree dissemination belongs to the migrants and wintering birds - woodpeckers, azure-winged magpies, thrushes and waxwings, distributing seeds on the feeding places and transferring them on the different distances from the areas of the plant growing.