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Three-component simultaneous seismic records of quarry blasts were processed using a new approach of wavelet representation of the inhomogeneity parameter. The results show that quarry blasts can be successfully used in controlled-source seismic monitoring.

Physical, physicochemical, and petrographic methods were applied to investigate temperature dependences of dc and ac electrical resistance and dielectric loss, as well as their correlation, in the range from 20 to 850

The Cambrian-Ordovician tectonic evolution of the Kokchetav metamorphic belt containing UHP-HP rocks proceeded through several stages. The subduction of the Paleoasian Ocean lithosphere, containing blocks of continental crust, and collision of the Kokchetav microcontinent with island arcs are responsible for the formation and exhumation of UHP-HP rocks. Initially, in the Early Cambrian (535-523 Ma), the microcontinent was subsided into the subduction zone to depths of 150-200 km, which led to metamorphism as well as to partial melting of rocks. In next substage (523-513 Ma), the produced acid melts including blocks of UHP-HP rocks were exhumated quickly, at a velocity of up to 100-10 cm/year, to depths of 90 km, which permitted the preservation of the high-pressure associations. Then, the UHP-HP rocks were exhumated at a velocity of 0.5 cm/year along faulting zones of the accretionary wedge to depths of 30 km. In the Middle and Late Cambrian (513-480 Ma), the continuing subduction of the Kokchetav microcontinent led to the outwedging of the subduction zone, extrusion of UHP-HP rocks along retro-overthrust zones, heaping and overthrust in the accretionary prism. The formation of a new zone of subduction and the Late Arenigian-Early Caradocian collisional processes (480-450 Ma) led to the thrusting of allochthones, made up of the rocks of the Kokchetav microcontinent, and accretionary prism over the fore-arc trough of the Stepnyak island arc. The formation of an imbricated structure was completed with granitoid magmatism and accumulation of molasses in the Late Ordovician.

On the basis of the fundamental works of Academician Yu.A. Kuznetsov and later obtained research data, including ours, we have considered the geology, petrology, and petrochemistry of major types of Early Paleozoic granitoid associations of the Altai-Sayan area, as well as their role in the evolution of island-arc and collisional structures. Scarce early island-arc complexes are assigned to mantle tholeiitic plagiogranites. The superlarge areas of the mass occurrence of batholith granitoids formed at the accretion-collision stage have many geologo-lithologic peculiarities accounted for by their geodynamic settings. Study is given to early collisional K,Na-granitoid associations, Na-K-syenite-granite complexes of back-arc and continent-marginal zones, and Silurian collisional K-Na-granitoid complexes of the outer accretion zone, formed before magmatism took place on the Devonian active continental margin. The distribution of different types of associations is determined by the degree of maturity of the enclosing crust, which is expressed in the age and lateral compositional variations of granitoids. In general, the Early Paleozoic granitoid magmatism is specified by the existence of preceding basites of different types and repeated intense crushing of the enclosing rocks, which accompanied their metasomatism during the formation of granitoid plutons.

Data on the lithology of Lower Toarcian (Lower Jurassic) terrigenous sediments in the southeast of the West Siberian Plate are presented. Using cores from three parametric boreholes (mudstone (I), mudstone-siltstone (II), and sand (III) sections), the petrography and mineralogy of the sediment clays have been studied. The mineral composition was determined by optical and electron microscopy, X-ray diffraction, and IR spectroscopy. A comparative analysis of the associations, crystal chemistry, and structure of clay minerals from the three sections was carried out by simulation of X-ray diffraction spectra. The clay matter from all sections is dominated by minerals of the kaolin group (kaolinite, dickite) and mica group (illite, muscovite). Chlorite minerals (chlorite, chlorite-smectite) are subordinate and occur in sections I and II only. It is shown that the degree of structural ordering of the kaolin group minerals varies depending on the grain size of rocks: from disordered kaolinites in the mudstones to more regular dickite in the sandstone and gravelstone cement.

A host of palynological data on West Siberia obtained recently at the Institute of Petroleum Geology have been considered and generalized, with the literature data on central Siberia and northeastern Russia invoked. The main large stages of sedimentation, formation, and evolution of sea and lake basins, evolution of floras and climate on the territory of Siberia in the Cenozoic are recognized and described. The Paleocene and Eocene Siberian palynofloras are taxonomically described in detail. Quantitative characteristics (temperatures of January and July, precipitation) of the climatic conditions of the Middle (optimum) and Late Eocene of Siberia have been obtained by the method of climatograms. Floristic relationships of Paleogenic palynofloras of Siberia with those from other regions are considered, with emphasis placed on their role in estimating the effect of paleoclimate and zoning on the distribution of vegetation zones.

The Talakan-Upper Chona zone of petroleum accumulation lies at the top of the Nepa arch. The largest Talakanskoe petroleum deposit has been discovered there, in carbonates of the Lower Cambrian Osa Horizon.
The structure of the Talakan petroleum field and data of prospecting drilling for oil and gas in the Irkutsk Region and in the Republic of Sakha (Yakutia) have shown that within the Talakan-Upper Chona zone a sublatitudinal Talakan-Ignyali marginal reef formed in Osa time. It extends along the southern margin of the Botuobiya-Talakan carbonate platform of Osa age. Also within the platform, there were bioherms and separating basins.
Analysis of the distribution and thicknesses of halite beds overlying the Osa Horizon shows that the lower beds of halites successively overlapped the surfaces of the Osa bioherms. Zones of thin deposits distinctly outline the Talakan-Ignyali marginal reef and bands of bioherms. The geomorphology of the Talakan-Upper Chona zone in late Osa-early Late Usol'ye time has been reconstructed from the distribution and thickness of the lower beds of halite. The sublatitudinal Talakan ridge no less than 20 m above sea level has been recognized there. North of the ridge lies the Upper Nyuya lowland flooded occasionally by sea waters. In the northeast and south of the Talakan-Upper Chona zone, there are margins of a halmeic sea basin. On the land, the most likely processes were karsting and destruction of carbonates of the Osa Horizon, which led to the formation of reservoirs of porous and cavernous types. The sublatitudinal position of the Talakan-Ignyali reef was not reflected in paleotectonic reconstructions of the zone.

Studies of the Emeishan and Siberian trap provinces have demonstrated abundance of basalt series and giant volumes of lavas and sills (~16 · 10⁶ km³) formed for a very short period of the major step of volcanism. The obtained data permit a model for superplumes with three steps of their formation: early (picrites and alkali basalts), major (tholeiite plateau basalts), and final (ultrabasic and alkaline intrusions). These steps reflect the evolution of a superplume from several independent plumes until the formation of thick lenses of mantle melts at the bottom of the lithosphere and, finally, plumes of differentiated mantle melts. Synchronous syenite-granite intrusions and bimodal volcanic series abundant in the framing of the Siberian traps are the result of melting of the lower crust at depths of 65-70 km under the effect of plume melts. Superplumes promoted the synchronization of events of magmatism and geologic processes repeated at intervals of 30 and 120 Myr. A similar synchronization of global geological events is observed during the activity of superplumes 120, 250 and, possibly, 360 and 480 Ma. During the effusion and intrusion of (8-16) · 10⁶ km³ of volcanic material for a short interval of 0.6-2 Myr, huge volumes of CO₂, SO₂, and HF might have been released, capable to destroy the atmospheric system, to disturb the budget of oxygen-free oceanic water, and to lead to the mass extinction of living organisms at the Permian-Triassic boundary.

We present results of laboratory modeling of thermochemical plumes rising from the core-mantle boundary. Laboratory modeling of plume rise based on the laboratory experiments shows that a plume keeps the same diameter till its eruption to the surface if the melting temperature of the ambient material remains invariable but develops a mushroom-shaped head if impinges on a high-melting layer.
Using theoretical modeling, we obtained pressure distribution in a rising plume and estimated an excess of pressure in the melt beneath the plume roof over the lithostatic pressure. The critical thickness of above-plume massif at which eruption conduit forms is compared with the available estimates from geological data.
A high-melting layer can occur in the upper mantle between 400 and 650 km at a certain relation between the melting curve of natural peridotite KLB-1 and melt temperature at the plume roof. The structure of a plume impinging on a high-melting layer is predicted in the reported model.

Based on new data on melt inclusions in minerals, the physicochemical and geochemical parameters of plateau-basalt magmatic systems of the Siberian Platform and Ontong Java, Pacific, have been established. The studied melts are enriched in Fe, which differs them from the magmatic melts of mid-ocean ridges (MOR). A comparative analysis of data on inclusions showed a similarity of continental and oceanic plateau-basalt magmatic systems, differing considerably from those of MOR and within-plate oceanic islands. Crystallization of oceanic plateau basalts took place at lower temperatures and pressures as compared with such rocks of the Siberian Platform. The data on inclusions evidence that the melts of the Siberian Platform and Malaita Island underwent a serious evolution in contrast to magmas of the Nauru Basin with more stable geochemical parameters. The most fractionated low-temperature high-Fe magmas with elevated contents of trace and rare-earth elements have been revealed for Malaita Island (Ontong Java Plateau).