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The Upper Pleistocene paleoclimatic records according to data of deep-water drilling in the Black Sea and Lake Baikal have been correlated. It has been shown that in both basins the two last interglacials were characterized by intense diatom sedimentation. It is stated that the appearance of diatom oozes in the sediments is related to an increased inflow of dissolved silica and nutrient salts. In oceans, this occurred during a rise of internal water, and on continents it was caused by surface runoff in the epochs of intense chemical weathering. The association of biogenic silica with uranium and organic matter (mainly humic acids) occurs not in Lake Baikal only but is also characteristic of upwelling zones, where sedimentation of humic acids and uranium is believed to occur at the water-bottom boundary. It has been found that the Baikal diatom sediments, already enriched in uranium in the superficial layer, further accumulate it immediately beneath the redox boundary. It has been demonstrated that the distribution of "clastophilic" elements in the column of the Upper Pleistocene Baikal sediments is a mirror image of distribution of biogenic silica as a thinner. Each event recognized in the oceanic paleoclimatic record in this time range is clearly pronounced in the sediment columns of the Akademichesky Ridge in Lake Baikal.

The regularities of distribution of S, Se, Te, U, Mo, B, P, Cu, Ag, Au, Sn, Zn, Pb, and organic carbon in Cenozoic sediments of various taphrogenic depressions in the Baikal Rift Zone have been studied. The fine-grained carbonaceous deposits of all depressions, particularly carbon partings and lutites of Lake Baikal, have concentrations of U several times higher than its clarke. The sediments of some river valleys are noticeably enriched in Au, which was supplied there from gold-ore deposits of sourcelands.
Organic matter and clayey sediments (or their lithified analogs) are the major concentrators and carriers of the above-listed elements. The most differentiated (according to the content of organic carbon) rocks exposed by BH-S-1 in the Tunka depression, where the concentration of C^org varies from 0.3 to 83% (in coal), show a certain distribution of elements between the organic and clayey matter, in accordance with their strength of bond with the latter: C^org-S-Se-U-Ag-Mo-B-Au-Te-Cu-Sn-Pb-Zn-clay.
The organic matter concentrates S, Se, U, Mo, and Ag, and the clayey matter concentrates Pb, Zn, Sn, and Cu. Gold and tellurium (which can bind with B, Mo, and Cu) behave in a specific way and indifferently with respect to the organic and clayey matter of the sediments, forming an independent terrigenous sedimentary material, probably, bearing native gold. Sometimes additional concentrators - phosphates, sulfates, and sulfides - are produced. In places, the behavior of these elements is different and even more intricate as a result of changes in the granulometric and mineral compositions of sediments. Diagenesis leads to a stronger separation of elements. Groups of elements tending to isolation as a result of differentiation at the sedimentation and diagenesis stage form associations typical of various ore deposits. It is suggested that the chemical processes of deposition and early diagenesis of the formed sediments in sedimentation basins are the initial stage of pre-ore differentiation of ore-forming elements in the originating source of matter for future deposits. This initial differentiation already exhibits the specific features of the forthcoming ore genesis.

Anomalies in pore water composition have been found in the 100m long core BDP-93 that was drilled in southern Lake Baikal, in four piston cores (1 to 8 m in length) taken from the same region, and in recent sediments from Frolikha Bay, a hydrothermal vent site in northern Lake Baikal. Pore water anomalies are manifested as significant increases in concentration of sulfates, bicarbonates, chlorides, and the ions of alkali and alkali-earth metals. Anomalies were found at different depths below the sediment-water interface (from centimeters to tens of meters), and the level of pore water enrichment in these components varies from station to station.
Anomalies have specific features in each of the Lake Baikal basins. It is shown that there is a genetic relationship between subaquatic and terrestrial centers of thermal-water discharge in northern Lake Baikal. These anomalous pore-water concentrations are presumably due to the leaching of ambient sediments
In southern Lake Baikal, in the Selenga river delta, ground waters of specific composition that are relics of ancient salt lakes could serve as a source of anomalous concentrations in pore-water components. Their influence may be realized through the extensive zones of increased permeability.

The paper presents new details of the structure of the basement and sedimentary cover of the southwestern edge of the North Baikal basin. The basement structure involves smaller-scale structures (Maloe More basin, Zama basin, and Zunduk-Zama horst), which, in turn, comprise third-order features. The presence of several en-echelon NE striking sub-basins within the Maloe More and Zama basins indicates that the tectonic framework of the region formed by listric and dextral faulting. Seismostratigraphy data and analysis of uppermost bottom sediments from BDP-96 and BDP-98 cores revealed three seismic layers in the sediment section, which are separated by discontinuities and can be correlated with deposits exposed on land in the neighboring Ol'khon region. Unit A' (X) correlates with the Lower-Middle Oligocene Ular'yar Formation, unit A, with the Lower-Middle Miocene Tagai Formation, and unit B, with the Upper Miocene-Pliocene Sasa Formation and with Quaternary deposits. The upper section of the Maloe More fill includes a separate seismic horizon correlatable with a layer of widely distributed fine-grained sand. Unit B, comprises three deposition centers within the limits of the Maloe More basin, i.e., large lakes existed in the region prior to the final stage of transgression from the North Baikal basin.
Thus, the southwestern edge of the Baikal basin has an intricate structure and underwent a complex evolution.

Results of analyses of the upper sedimentary layer from Lake Hovsgol (Mongolia) sampled with bottom cores in the Northern lake basin are presented. The core is characterized; the contents of moisture and biogenic silica as well as the composition of diatom species are determined at each 2 cm using light microscopy method. Palynological analysis is performed at continuous 2 cm intervals. The content of carbonate CO₂ is determined at each 10 cm.
The core obtained covered the end of glaciation and the entire Holocene. The Holocene boundary is determined by correlation of the studied core with numerous cores from other Mongolian lakes studied earlier. The mean sedimentation rate in the Northern basin in the Holocene was 7-8 cm per 1000 years.
The Pleistocene sediments contain a large amount of carbonates. In the Holocene sediments their concentration decreased abruptly.
The data obtained suggest convincingly that sampling of long sedimentation cores from Lake Hovsgol and their complex analysis can give very important information about the Pleistocene paleoclimates and, in particular, a deeper insight into the sedimentary record of Lake Baikal.

In recent two decades, new data on the age of strata and their spatial arrangement and geodynamic formation conditions have appeared, which give new insight into the geologic history of the Tien Shan. This mountain system evolved in several large megastages and stages, from the Archean through the Quaternary, which are recognized according to the predominant oceanic or continental regime of development. The fold-nappe structure of the Tien Shan is the result of crushing of the edge of the ancient supercontinent into a series of small blocks, which were then localized on the periphery of the Paleoasian ocean and underwent accretion, completed in the late Late Paleozoic.
The modern Eurasian plate within Central Asia is separated into several blocks, whose counter and rotational movements determine the recent geodynamics of the region. The Tien Shan lithosphere is layered as a result of the appearance of a migma layer in its lower part, which causes a relatively free transfer and deformation of its upper part.

New data on stratigraphy , tectonics, and magmatism of the Tien Shan ancient rocks suggest the plate-tectonic interpretation of the structure and evolution of the Tien Shan nappe-folded orogen. A new scheme of tectonic regionalization has been proposed for the Kyrgyz Tien Shan. Emphasis is placed on recognition of geodynamic complexes (continents, microcontinents, passive and active margins, open ocean basins, and marginal seas) and structural elements (autochthons, para-autochthons, allochthons, and neoautochthons), governing the spatial arrangement of their units with specific texture and composition. Over the long geologic history of the territory, the continental blocks changed their outlines, and ocean basins appeared and disappeared. The Caledonian and Hercynian orogenies in the Tien Shan underwent a complete Wilson cycle. The Mesozoic history was controlled by within-plate processes of sedimentation and magmatism. Since the Oligocene, the Tien Shan territory has been involved in the recent orogeny.

The types and subtypes of a density section of the Earth's crust in the zone limited by the Talas-Fergana and East Fergana faults are considered. The zone has an inversion deconsolidated layer in the lower crust (35-50 km). Rock densities are calculated by an empirical formula with the use of seismic tomography data on P- and S-wave velocities. In the geological aspect this territory is remarkable as it involves the South Tien Shan ophiolite belt notching a suture which resulted from the closure of Turkestan paleoocean in the Middle Carboniferous. In the Earth's crust section the suture is traceable to a depth of 15-20 km, is cone-shaped, and is characterized by an increased density of rocks. Analysis of the gravimetric field and density sections suggests that within this cone the Earth's crust is saturated with rocks of ophiolite association.

The paper presents the dip angles of a seismofocal zone, the rate of underthrust, and other kinematic parameters of Middle Carboniferous-Early Permian subduction in northern Fergana, reconstructed from the petrochemical features of coeval magmatites. Comparison of these parameters with those in zones on some modern active continental margins suggests the metallogenic similarity of these regions.

The paper presents new data on several ore fields and mineral deposits of the Tien Shan spatially associated with transregional NW faults, which are easily identified by geophysical methods as they are marked by epicenters of shallow earthquakes and their aftershocks and abnormal heat flux (up to 130 mW/m ²). The faults inherit the strike of older faults and cross structures of the "Tien Shan" orientation.
In a low-seismisity block east of the Talas-Fergana fault (east of 74 ^oE), MT soundings reveal a continuous crustal conductor, and the behavior of P waves indicates the presence of waveguides. The block involves the Barskoon zone of deep faults and a number of rift depressions. A large gold deposit (Kumtor) occurs at the intersection of the Borskoon fault with the Mid Tien Shan back-arc magmatic belt and the "Nikolaev line".