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The mountains systems of Central Asia are primary targets to study late Pleistocene climate evolution given their location at the crossroads of several atmospheric circulation systems. The timing of glacier extent during this period remains understudied, especially in the Altai Mountains. Here, we have reconstructed glacier extent during three main Late Pleistocene stadials in the upper Kalguty basin (south‐eastern Russian Altai) based on field‐based geomorphic analysis. Additionally, surface exposure dating with 10Be and 26Al at a key site was used to infer a minimum‐limiting age for the outermost well‐preserved Pleistocene frontal moraine system and to date the inception of glacier withdrawal. According to our data, around 20.6 ± 1.8 ka Kalguty Glacier was still 200 m thick at the key site, 10 km upstream of the outermost moraine, and the site was totally deglaciated shortly after 20.4 ± 0.4 ka. These results point to a rapid retreat of this low‐gradient valley glacier after its probably MIS 2 maximum which was prior to 21 ka and probably prior to 22.5 ka. Two other glacier stages have been identified upvalley, characterized by a depression of the equilibrium‐line altitude of 420 and 314 m with respect to the Little Ice Age, thus corresponding to Lateglacial advances. Our glacier reconstruction further provides a geomorphological and geochronological background to put into context archaeological findings in this area. [ABSTRACT FROM AUTHOR]

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The silica-scaled chrysophyte flora of some lakes and rivers of the Altai Mountains was investigated by means of electron microscopy. Teletskoye Lake; the Biya, Chulyshman, and Katun Rivers; and small lakes around the area were studied. A total of sixteen taxa were recorded, including eight belonging to Mallomonas, five to Synura, and three to Paraphysomonas. A revision of previously reported taxa of scaled chrysophytes in this region was carried out. One species new to science from the genus Mallomonas was found and described. Mallomonas altaica sp. nov. belongs to the section Striatae and is characterised by scales with ribs covering only the anterior part of the shield and a posterior flange almost completely covered with the secondary siliceous layer. This species was discovered only at Teletskoye Lake. [ABSTRACT FROM AUTHOR]

In this work, the reconstruction of past vegetation and fire dynamics in northern Altai is performed by a pollen and charcoal investigation into the peat deposits of the Maly Labysh mire located in the upper reaches of the Kondoma River in Shorsky National Park. Lithology and radiocarbon dating have shown that the mire is of lacustrine origin. An oxbow lake originated about 3000 years ago, and about 2200 years ago it turned into a swamp. A spore–pollen (SP) analysis of lacustrine and peat deposits revealed repeated changes in the vegetation cover, probably caused by climate instability during the last 3000 years. In general, two humid millennial periods (3000–1800 cal yr BP and 550–200 cal yr BP) were identified when the role of fir increased in the forests, alternating with two drier periods (1600–900 cal yr BP and 200 cal yr BP—contemporary), when the fir gave way to birch forests. This article also represents data on the dynamics of paleofires in the area of the Maly Labysh mire based on micro- and macrocharcoal analyses. A comparison of the results of pollen and charcoal investigations with other paleoclimatic reconstructions in Western Siberia in the Holocene is given. A conclusion is drawn about the connection between paleofires and the dynamics of humidity of the climate, which together influenced the vegetation change in Gornaya Shoriya. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dil Araştırmaları is the property of Journal of Dil Arastirmalari and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A comparison of karren formation on various rocks under diverse environmental conditions makes an important contribution to our understanding of the formation and development of karst. In this regard, the present study brings a number of new insights through description of the karst development on marbles at the foothills of the Altai Mountains. We studied karst phenomena in the field and in laboratory where structural-textural properties, mineral composition and quantity of carbonate components were determined. Rivers dissected karst surface and additionally uncovered carbonate rocks. The marble layers are faulted, folded and sheared, consequently containing numerous densely spaced net of discontinuities, which are often parallel. Brittle deformations significantly increased the rocks' porosity, consequently making it more sensitive to water absorption and freezing thaw effect. Distinct continental climate, with extreme daily and seasonal temperature variations, conditions the pronounced peeling off of the marbles along discontinuities. The diversity of disintegration is conditioned by the massive or oriented structure, cleavage, texture, and type and grainsize of the marbles' mineral constituents. Interaction and alternation of chemical dissolution and mechanical disintegration play the major role on the karren formation and its preservation. The formed karren is mostly destroyed due to peeling off and disintegration of the marbles. [ABSTRACT FROM AUTHOR]

Spanning the northern sector of High Asia, the Altai region contains a rich landform record of glaciation. We report the extent, chronologies, and dynamics of two paleoglaciers on opposite flanks of the Ikh Turgen mountains (In Russian: Chikhacheva Range), straddling the border between Russia and Mongolia, using a combination of remote sensing-based glacial geomorphological mapping, 10 Be surface exposure dating, and geomorphometric analysis. On the eastern side (Mongolia), the Turgen-Asgat paleoglacier, with its potential for developing a large accumulation area (∼257 km 2 ), expanded 40 km down valley, and mean ages from a latero-frontal moraine indicate deglaciation during marine oxygen isotope stage (MIS) 3 (45.1 ± 1.8 ka, n = 4) and MIS 2 (22.8 ± 3.3 ka, n = 5). These minimum age constraints are consistent with other 10 Be glacial chronologies and paleoclimate records from the region, which indicates glacier culmination during cold and wet conditions coinciding with MIS 3 (piedmont-style glaciation; inferred for a few sites across the region) and glacier culmination during cold and dry conditions coinciding with MIS 2 (mainly valley-style glaciation; inferred from several sites across the region). On the western side (Russia), the Boguty paleoglacier had a smaller accumulation area (∼222 km 2 ), and advanced 30 km down valley across a low gradient forefield. Surface exposure ages from two moraine complexes on this side of the mountains exhibit wide scatter (∼14–53 ka, n = 8), making paleoclimate inferences and comparison to other proxies difficult. Ice surface profile reconstructions imply that the two paleoglaciers likely shared an ice divide. [ABSTRACT FROM AUTHOR]

Using pollen analysis and metabarcoding of plant sedimentary ancient DNA (sedaDNa), we infer the floristic diversity in the vicinity of Lake Balyktukel, Ulagan Plateau, the Altai Mountains, over the last 7 kyr. The SedaDNA method identified 200% more taxa than found by morphological pollen analysis. In particular, it revealed that the dominant tree for the last 7 kyr was Larix rather than Pinus , which was less frequent in the vicinity of Lake Balyktukel. About 7 ka, larch forest mixed with dwarf birch was widespread on the Ulagan Plateau. The period between 5.3 and 3.4 kyr BP was characterized by the maximal spread of larch forest with an understorey cover of Vaccinium vitis-idaea. Pollen-based annual precipitation reconstruction indicates the most humid phase was between 6.95 and 4.3 ka, and generally coincides with maximal phytodiversity. The most bioproductive period of the lake was from 7 to 6 ka. After that, the trophicity of the lake decreased until 4.5 ka. The appearance of Hippuris vulgaris and increase in Ranunculus subgen. Batrachium at about 5.3–5 ka may indicate the extension of shallow-water ecotopes. Between 3.7 and 3.5 ka, the cyanobacterium Anabaena – an indicator of increased organic matter and algal blooms – was widespread. A planktic thermophilic cladoceran Bosmina longirostris appeared after 1.8 ka and colonized the lake, suggesting an increase in lake trophicity. The last 100 years have been characterized by dramatic changes in the cladoceran community reflecting significant warming of climate. [Display omitted] • In plant communities dominated by larch, pollen analysis does not adequately reflect the composition of dominant trees • Identification of larch via sedaDNA analysis is much more effective than by pollen analysis • Aquatic macrophytes are poorly detected by pollen analysis in lake sediments, but are reliably detected by sedaDNA analysis • Cladoceran composition reflects significant climate warming during the last century [ABSTRACT FROM AUTHOR]

The Altai Mountains are a heritage-rich archaeological landscape with monuments in almost every valley. Modern nation state borders dissect the region and limit archaeological landscape analysis to intra-national areas of interest. Remote sensing can help to overcome these limitations. Due to its high precision, Synthetic Aperture Radar (SAR) data can be a very useful tool for supporting archaeological prospections, but compared to optical imagery, the detectability of sites of archaeological interest is limited. We analyzed the limitations of SAR using TerraSAR-X images in different modes. Based on ground truth, the discernibility of burial mounds was analyzed in different SAR acquisition modes. We show that very-high-resolution TerraSAR-X staring spotlight images are very well suited for the task, with >75% of the larger mounds being discernible, while in images with a lower spatial resolution only a few large sites can be detected, at rates below 50%. [ABSTRACT FROM AUTHOR]

A new species of ground spider, Parasyrisca golyakovi sp. n. is described based on female from the Altai Mountains. A previously unknown female of P. ulykpani Ovtsharenko, Platnick & Marusik, 1995 is described for the first time. [ABSTRACT FROM AUTHOR]

Glaciers in the Altai Mountains of Mongolia provide an estimated 11% of the total water resources within the country. Yet, their number and area in inconsistent. Using satellite imagery acquired from Landsat 4, 5, and 7, and SRTM digital elevation model (DEM) data, we present here an intuitive, robust, and inexpensive methodology to map the exposed ice of glaciers in the Altai Mountains for the period 1989 to 2011. The total glacierized area was 515 km2 in 1989/1991, 428 km2 in 1998/2001, and 372 km2 in 2010/2011; it decreased by 17% from 1989/1991 to 1998/2001, 13% from 1998/2001 to 2010/2011, and 28% for the entire period 1989/1991 to 2010/2011. In analyzing a sub-sample of 260 glaciers, 6% advanced, 11% were stable, and 83% receded from 1989 to 2011. The glacier dataset is available to the public free of charge at the Global Land Ice Measurements from Space (GLIMS) website. [ABSTRACT FROM AUTHOR]

Results of research into climate and glacier dynamics in the Altai Mountains (Russia) over the period of instrumental observations (1952-2008) are presented in this article. About 1030 glaciers with a total area of 805 km and volume of 42.5 km have been recorded in the Altai Region. The average summer air temperature in different regions of the Altai has increased during the study period from about 0.2°C (Aktru) to 1.1°C (Akkem). The annual atmospheric precipitation rate has also increased, by 8-10%. Since 1952, the glacier area in different regions of the Altai has decreased by 9-27%, and volume by 12-24%. By 2008, as a result of degradation, the total number of glaciers was 953 with an area of 724 km and volume of 38 km. [ABSTRACT FROM AUTHOR]

Abstract: The Mengku iron deposit (110Mt at 44% Fe) in the eastern extension of the Rudnyi Altai mineral belt, Xinjiang, NW China, is hosted in an Early Devonian volcano-sedimentary sequence affected by prograde skarn formation (clinopyroxene, garnet, scapolite and albite) and retrograde alteration (actinolite, epidote, chlorite and apatite). Ore minerals are magnetite, with minor chalcopyrite, pyrrhotite and pyrite. Gangue minerals include predominantly diopside, andradite, epidote, chlorite, quartz and calcite. Fluid inclusions in garnet and clinopyroxene yield homogenization temperatures (Th) of 241–500°C, and salinities of 9.6–13.0wt.% NaCl equivalent. Fluid inclusions in quartz consist of two varieties: (1) liquid–vapor–solid inclusions with (Th) of 348–458°C and salinities of 38.2–57.1wt.%, and (2) two-phase inclusions with (Th) of 166–382°C and salinities of 9.6–13.0wt.% NaCl equivalent. Two-phase inclusions in calcite vary from 145 to 265°C, with salinities of 1.2–9.6wt.% NaCl equivalent. The fluid evolution progressed from high temperature and moderate salinity (prograde skarn stage) to moderate T and salinity (retrograde stage), to low T and salinity (sulfide stage). Stable isotope data of quartz and calcite (−84‰ to −110‰ δD, 5.5–7.0‰ δ18OSMOW, and −3.8‰ to −6.1‰ δ13CPDB) reflect late-stage interaction of meteoric water with granitic rocks. Skarn formation was likely related to a Late Devonian tonalite (378±7Ma, U–Pb zircon age). The geological and geochemical evidence suggests magnetite skarn formation from granite-related fluids which reacted with andesitic to mafic volcanics and their intercalated carbonate beds and lenses, contrary to earlier interpretations of the deposit as of synsedimentary-exhalative origin or related to iron–oxide magma. [Copyright &y& Elsevier]

Abstract: The Altai range (western Mongolia) accommodates NNE–SSW shortening across the northern India–Eurasia collision zone by dextral slip on faults trending NNW–SSE, and anticlockwise, vertical-axis rotations of fault-bounded blocks. However, fault slip-rates and the way in which faulting evolves over time are poorly understood, and form the motivation for this study. We focussed on the Har-Us-Nuur fault, a major transpressional fault bounding the eastern margin of the Altai. Three abandoned alluvial fan surfaces, each displaced right-laterally by the fault, were targeted for dating with cosmogenic 10Be and quartz optically stimulated luminescence (OSL). The first surface (A2) shows an exponential decrease in 10Be with increasing depth, with a significant inherited component. Modelling this profile yielded a minimum age of 74.1 ka. Material from the same sampling pit was dated at ~19 ka with OSL, but we consider this younger age to be incorrect, possibly due to feldspar contamination or abnormal quartz OSL characteristics. The A2 surface is displaced by 175 m, implying a (maximum) dextral slip-rate of 2.4±0.4 mm yr−1. A second fan surface (F1) was dated at ~6 ka with OSL and shows little variation in 10Be with depth, consistent with this young age. The inherited component is higher than for A2, indicating contrasting levels of inheritance for different periods of fan aggradation. A final surface (F2) shows scattered 10Be concentrations and lacks material suitable for OSL, so cannot be dated precisely. Using the total vertical displacement across the fault, we place the initiation of movement on the fault at ~2 Ma, significantly later than the late Oligocene to Miocene (28–5 Ma) onset of shortening in the Altai region. This suggests that deformation in the Altai has widened over time to incorporate new faults at the range margins (such as Har-Us-Nuur), possibly because older faults in the range interior have rotated about vertical axes into orientations that require work to be done against gravity. [Copyright &y& Elsevier]

The objective of this study is to reveal the isotopic composition of ice and meltwater in glaciated regions of South-Eastern Altai. The paper depicts differences between the isotopic composition of glacier ice from several types of glaciers and from various locations. Detected differences between the isotopic composition of glacier ice in diversified parts of the study region are related to local climate patterns. Isotopic composition of meltwater and isotopic separation for glacier rivers runoff showed that in the Tavan-Bogd massif, seasonal snow participates more in the formation of glacier runoff due to better conditions for snow accumulation on the surface of glaciers. In other research areas pure glacier meltwater prevails in runoff. [ABSTRACT FROM AUTHOR]

The 2003 September 27 Mw 7.2 Siberian Altai earthquake was the largest to have struck the Altai mountains in more than seventy years, and was closely followed by two Mw 6.2 and 6.6 aftershocks. We use radar interferometry, seismic bodywaves and field investigations to examine the source processes of these earthquakes. The main shock of the initial earthquake ruptured a subvertical, ∼NW–SE striking dextral strike-slip fault. The fault was previously unrecognised; although it approximately follows the southwestern boundaries of two intermontane depressions within the interior northwestern Altai, it has very little topographic expression. A ∼NE-dipping reverse subevent, possibly triggered by shear waves from the main shock, occurred ten seconds afterwards strike to the southeast. The later Mw 6.2 and 6.6 aftershocks were dextral strike-slip events which contributed further to deformation in the northwest part of the fault zone. However, interferometric and bodywave models disagree significantly on the source parameters of the earthquakes, in particular the total moment released and the dip of the fault planes. Trade-offs of fault dip with moment and centroid depth in the bodywave modelling can account for some, but not all, of these discrepancies. The interferometric data is unevenly distributed, containing many more data points on one side of the fault zone than the other; however, on the basis of calculations with synthetic data we rule this out as a reason for the discrepancies in fault parameters. The lower moment predicted by interferometry could be explained by the lack of coherent data close to the faulting, if slip was concentrated at very shallow depths. The dip yielded by the interferometric modelling might be influenced by lateral changes in elastic properties, although these would also affect the bodywave solutions. The earthquake sequence occurred close to recent palaeomagnetic measurements of late Cenozoic anticlockwise rotations. These suggest that the right-lateral strike-slip faulting that ruptured in the 2003 earthquakes accommodates regional ∼NNE–SSW shortening by rotating anticlockwise over time. The reverse subevent is a rare case of pure shortening perpendicular to the trend of the Altai range. [ABSTRACT FROM AUTHOR]

Abstract: Satellite imagery, and specifically CORONA, is now of common use in archaeology. CORONA, as it produces two images of the same spot (afterward and forward), allows for stereoscopic view and is a perfect tool for the production of maps, especially in remote areas, where maps are not reliable of even absent. However, in all cases until now, often, it appears that only one of both images is used and that one considers this view as a geographical correct image. This is not correct. Using the test case of fieldwork and research in the Altai Mountains, we suggest that one should use both images of the same spot. Firstly, the two images give different information (shadow, lighting, different angles). Secondly, the use of both images, after georeferencing, makes it possible to produce orthophoto''s and DSM''s. For a correct georeferenced orthophoto, there is a need for a correct positioning of a certain amount of ground control points (GCP''s). During the fieldwork in Altai, we tested several GPS devices. It appears that C&C C-Nav, a dual frequency, geodetic grade, GPS receiver, is a highly optimised equipment for the production of GCP''s, and can be used for all types of satellite images. Common hand-held Garmin 12XL and Motorola Oncore VP hand-held GPS receivers are suitable for the localisation of archaeological sites and objects, on the condition of extensive post-processing using network solutions. These devices can also be used for CORONA as well as for other satellite images, with a resolution up to 2–4 m. [Copyright &y& Elsevier]

Abstract: Mountain ranges that are actively forming around the western and northern perimeter of the Indo-Eurasia collisional deformational field, such as the Mongolian Altai, comprise a unique class of intracontinental intraplate transpressional orogen with structural and basinal elements that are distinct from contractional and extensional orogens. Late Cenozoic uplift and mountain building in the Mongolian Altai is dominated by regional-scale dextral strike–slip faults that link with thrust and oblique–slip faults within a 300-km-wide deforming belt sandwiched between the more rigid Junggar Basin block and Hangay Precambrian craton. Dominant orogenic elements in the Mongolian Altai include double restraining bends, terminal restraining bends, partial restraining bends, single thrust ridges, thrust ridges linked by strike–slip faults, and triangular block uplifts in areas of conjugate strike–slip faults. The overall pattern is similar to a regional strike–slip duplex array; however, the significant amount of contractional and oblique–slip displacement within the range and large number of historical oblique–slip seismic events renders the term “transpressional duplex” more accurate. Intramontane and range flanking basins can be classified as ramp basins, half-ramp basins, open-sided thrust basins, pull-apart basins, and strike–slip basins. Neither a classic fold-and-thrust orogenic wedge geometry nor a bounding foredeep exists. The manner in which upper crustal transpressional deformation is balanced in the lower crust is unknown; however, crustal thickening by lower crustal inflation and northward outflow of lower crustal material are consistent with existing geological and geodetic data and could account for late Cenozoic regional epeirogenic uplift in the Russian Altai and Sayan regions. [Copyright &y& Elsevier]

• New apatite fission track ages for N = 6 samples range from 68 to 104 Ma. • Apatite U-Th-Sm/He dates range from 56 to 272 Ma for N = 23 samples. • Inverse modeling indicates fast cooling during the late Early Cretaceous. • These data suggest <1–2 km exhumation has occurred in Chinese Altai since the Paleocene. • Late Cenozoic surface uplift in the Chinese must have been associated with minimal erosion. The Chinese Altai Mountains in western China are bound by Cenozoic transpressional strike-slip faults, many of which show Quaternary activity. To better understand how Mesozoic–Cenozoic deformation has affected the history of exhumation and uplift of the Chinese Altai Mountains, we collected Paleozoic granitoid samples for apatite fission track and apatite U-Th-Sm/He thermochronology. Central apatite fission track ages for N = 6 samples range from 68 to 104 Ma, whereas apatite U-Th-Sm/He ages range from 56 to 272 Ma for N = 23 samples (n = 80 individual analyses) across four transects in the western Chinese Altai. Our results indicate fast cooling during the late Early Cretaceous followed by slow cooling since. Thermal modeling results suggests < 2 km exhumation has occurred over most of the Chinese Altai since the Paleocene. If significant late Cenozoic surface uplift occurred in the Altai Mountains, as has been proposed, it must have been associated with minimal erosional exhumation. We suggest that the relief of the Chinese Altai largely developed during the late Mesozoic and denudation since has been minimal because of semi-arid climate conditions. [ABSTRACT FROM AUTHOR]

The Tavan Bogd mountains (of which, the main peak, Khuiten Uul, reaches 4374 m a.s.l.) are situated in the central part of the Altai mountain system, in the territories of Russia, Mongolia and China. The massif is the largest glacierized area of Altai. The purposes of this study were to provide a full description of the scale and structure of the modern glacierized area of the Tavan Bogd massif, to reconstruct the glaciers of the Little Ice Age (LIA), to estimate the extent of the glaciers in 1968, and to determine the main glacial trends, and their causes, from the peak of the LIA. This work was based on the results of long-term field studies and analysis of satellite and aerial data. At the peak of the LIA, Tavan Bogd glaciation comprised 243 glaciers with a total area of 353.4 km2. From interpretation of Corona images, by 1968 the number of glaciers had decreased to 236, with a total area of 242 km2. In 2010, there were 225 glaciers with a total area of 201 km2. Thus, since the peak of the LIA, the glacierized area of the Tavan Bogd mountains decreased by 43%, which is somewhat less than for neighboring glacial centers (i.e., Ikh-Turgen, Tsambagarav, Tsengel-Khairkhan and Mongun-Taiga mountains). The probable causes are higher altitude and the predominance of larger glaciers resistant to warming. Accordingly, the smallest decline in Tavan Bogd occurred in the basins of the Tsagan-Gol (31.7%) and Sangadyr (36.4%) rivers where the largest glaciers are located. In contrast, on the lower periphery of the massif, where small glaciers predominate, the relative reduction was large (74–79%). In terms of general retreat trends, large valley glaciers retreated faster in 1968–1977 and after 2010. During the 1990s, the retreat was slow. After 2010, glacial retreat was rapid. The retreat of glaciers in the last 50–60 years was caused by a trend decrease in precipitation until the mid-1970s, and a sharp warming in the 1990s and early 2000s. [ABSTRACT FROM AUTHOR]

Pollen taxa in sediment samples can be identified based on morphology. However, closely related species do not differ substantially in pollen morphology, and accurate identification is generally limited to genera or families. Because many pollen grains in glaciers contain protoplasm, genetic information obtained from pollen grains should enable the identification of plant taxa at the species level. In the present study, species identification of Pinus pollen grains was attempted using whole-genome amplification (WGA). We used pollen grains extracted from surface snow (depth, 1.8–1.9 m) from the Belukha glacier in the summer of 2003. WGA was performed using a single pollen grain. Some regions of the chloroplast genome were amplified by PCR, and the DNA products were sequenced to identify the pollen grain. Pinus includes approximately 111 recognized species in two subgenera, four sections, and 11 subsections. The tree species Pinus sibirica and P. sylvestris are currently found at the periphery of the glacier. We identified the pollen grains from the Belukha glacier to the level of section or subsection to which P. sibirica and P. sylvestris belong. Moreover, we specifically identified two pollen grains as P. sibirica or P. cembra. Fifteen species, including P. sibirica, were candidates for the remaining pollen grain. [ABSTRACT FROM AUTHOR]