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Geological and hydrobiogeochemical studies carried out in two areas of active geophagy among herbivorous animals in the area of Teletskoye Lake in the Altai Mountains suggest that consumption of lithogenic substances by animals is typical for mountain-taiga and mountain-steppe landscapes with high soluble REE contents in rocks. The high soluble REE contents were measured in the deluvial deposits of some magmatic and metamorphic rocks, as well as in the associated glacial deposits and in the derived soils and vegetation. The revealed geochemical specificity of landscapes similar to that previously established in the Sikhote-Alin becomes the cause of unbalance in the composition and concentration of REEs in the neuroimmunoendocrine system of the animal body. Being in a state of hormonal stress, animals try to compensate for this problem by consuming mineral sorbents, which, as we found out, can remove excess REEs from the body. [ABSTRACT FROM AUTHOR]

New results of Optically-Stimulated Luminescence (OSL) dating that make it possible to clarify the age of the Chibitskii glaciation in the Altai Mountains are reported. Three dates were obtained from the upper part of the lacustrine–glacial Baratal sands, logically distributed within the chronological interval from 21.0 to 14.4 ka. Fluvioglacial sands from the drift moraines of the last Kuekhtanar glacier, three OSL-ages of which are in the interval of 30–24 ka, correlate with the Baratal limnoglacial. The origin of Sukor Lake is associated with the Sukor landslide, which dammed the Chuya River valley. According to eight OSL dates, which have been obtained for the Sukor sands, the dammed Sukor Lake existed in the interval from 16 to 11 ka. New OSL dates provide a more reliable reconstruction of the Chibit glaciation age and the position of the corresponding sediments in the Quaternary stratigraphic chart of the Altai–Sayan Mountain Country, as corresponding to the Last Glacial Maximum (LGM), i.e., the fourth stage of the Upper Neopleistocene of the Russian stratigraphic chart. [ABSTRACT FROM AUTHOR]

The data presented introduce substantial changes into Quaternary stratigraphy, paleogeography, and the geological history of the Altai Mountains. The purpose of this investigation was thorough study of block accumulations in the Chuya and Katun river valleys. The new data shed light on the structure of these deposits, their composition, the geomorphological and stratigraphic position, and the morphology of blocks. The revealed morphological features of individual blocks imply their glacial origin. [ABSTRACT FROM AUTHOR]

A mathematical model based on thermomechanical equations of mechanics of deformable solids was suggested to study the mechanism of collision and metamorphism in rocks of the Mongolian Altai orogen. The problem of crust deformation and distribution of the P-T parameters of metamorphism in the Tsogt block in the course of convergence of the Edren island-arc terrane and the Gobi-Altai back-arc terrane was considered. The results of mathematical modeling explain the 1.5-fold thickening of the crust (rock subsidence by 15-18 km), which is consistent with pressure estimates of metamorphism obtained from the data of geothermobarometry. Modeling provides estimates of the plate convergence rate by comparison of the calculated temperatures with the data of thermobarometry for rocks of the Tsogt metamorphic complex within the Tseel terrane. [ABSTRACT FROM AUTHOR]

The article looks at a study done to investigate the reduction of Altai Glaciers in Russia and Kazakhstan. Topics discussed include characteristics of glaciation at several main glaciation centers and specified the terminal point positions including Big Taldura, Alakha and Sofiiskii; spatial structure of Alatai Glaciation; and evolution of concrete areas of glaciation in the ranges and their fractions.

The article presents information on a study conducted for determination of Paleozoic age relationships between brittle-plastic deformations and metamorphism within the Tseel metamorphic belt located in the southwestern part of Mongolian Altai mountains. It mentions that the geochronology of the successive stages of metamorphism of the mountain belt was analyzed by uranium-lead dating method by synmetamorphic granitoids and gabbroids. It highlights that chronology of stages of metamorphism and deformation plays important role in determination of history of the formation of accretional structures in Central Asia.

It has been found that basalts of the Irbistu River basin (southeast Altai Mountains) belong to the intraplate OIB type. The peculiarities of their material composition do not indicate interaction effects between the basic melt and continental crust, and signifies that there was a magmatic source in the moderately depleted mantle comparable to the HIMU domain. It is suggested that basalts of the Irbistu River basin, along with other manifestations of similar volcanites in the Altai Mountains, reflect the Neoproterozoic-Early Paleozoic stage of the North Asian plume's activity during closure of the Paleoasian Ocean. [ABSTRACT FROM AUTHOR]

The article discusses the study done on the Altai Mountains in Russia to examine the new aspects of application of dendrochronological analysis for the dating of strong earthquakes that were occurred in the past. Topics discussed include seismic zoning and distinguishing the territories of high seismic activity, spreading the forest vegetation in seismically active areas, and dendrochronological dating of paleoearthquakes.