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Recent results indicate contrasting Holocene moisture histories at different elevations in arid central Asia (ACA). However, relatively little is known about Holocene temperature changes at different elevations. Here we report an independently dated peat brGDGTs‐based MBT'5ME record from the Narenxia peatland (NRX) in the southern Altai Mountains. The record suggests a long‐term warming trend since ~7.7 cal. kyr bp, with a warmer stage during ~7–5.5 cal. kyr bp, a cold stage during ~5.5–4 cal. kyr bp, and a warming trend over the last ~4 kyr. The long‐term warming trend indicated by the NRX MBT'5ME record is largely consistent with Holocene temperature records from nearby sites covering an altitudinal range of ~1700–4100 m above sea level. This consistent long‐term warming trend at different elevations differs from the long‐term Holocene drying/wetting trends at high/low elevations of the Altai Mountains. We propose that the warming trend and consequent permafrost thawing at high elevations could have resulted in increased meltwater runoff, which would have contributed to the long‐term wetting trend at low elevations. Our findings potentially provide an improved understanding of regional climate change and associated water resource availability, with implications for their possible future status. [ABSTRACT FROM AUTHOR]

Here, we apply geometric-morphometric shape analysis to Middle Paleolithic bone retouchers from Chagyrskaya Cave in the Altai Mountains of southern Siberia. The cave contains evidence of the easternmost manifestation of the Micoquian industry, associated with Neanderthals at end of MIS4 and the beginning of MIS3. Taphonomic and scar pattern analyses were performed first on random samples exhibiting appropriate characteristics. Several retouchers produced on intentionally modified blanks were identified in our sample, suggesting that some of the Chagyrskaya Cave bone retouchers can be described as formal tools. All retouchers from Chagyrskaya Cave exhibit a similar general morphology. The most variable group is comprised of complete retouchers without blank modifications. Retouchers exhibiting minor damage affect the general pattern of variability and it is not possible to identify them only by means of geometric-morphometric shape analysis. Complete retouchers with blank modifications fall within the range of variability of complete retouchers without blank modification, suggesting intentional shaping of blanks to conform to a standard template. The range of variability of the bone retouchers does not differ significantly from that of the most highly modified lithic artifacts at Chagyrskaya – plano-convex bifaces – which may indicate intentional shape control for such artifacts. Geometric-morphometric analysis indicates that the anatomical origin of bone blanks does not significantly influence the retouchers' shape, which may point to strict blank selection and, at the same time, intentional modification. Our results raise questions regarding the integration of retouchers into a complex, multidimensional "chaine-opératoire" as well as the nature of Neanderthal cognitive abilities. Geometric-morphometric shape analysis represents a major step forward in the study of prehistoric retouchers. [ABSTRACT FROM AUTHOR]

Eidophasia assmanni sp. nov., a new species of Plutellidae from the alpine zone of Russian Altai Mountains, is described from diagnostic morphology and DNA barcodes. Male adult and genitalia are illustrated, whereas the female sex remains unknown. The species inhabits alpine scree with patchy herbaceous plants and is considered as possible endemic species of the Altai Mountains. An updated checklist of the 13 global Eidophasia Stephens, 1842 species is provided. The likely polyphyly of the genus is discussed from molecular data of the barcode region of the mt COI gene. [ABSTRACT FROM AUTHOR]

The analysis of satellite images revealed by 25% decrease of the Altai mountains' glaciation area over last 50 years. In 2008–2017, deglaciation rate increased twice. This tendency is in good agreement with an observed increase in the Katun River flow by 9% in 2008–2017 as compared to 1940–1968 (under invariable total precipitation). The analysis of trends of main meteorological parameters based on weather station data and the ERA-Interim reanalysis demonstrated that statistically significant warming in the region occurs only during the warm season and does not exceed 0.5°С/10 years. For this reason, "atmosphere–glaciers" turbulent heat transfer has increased by 4 W/m2 in last two years, that caused an annual melting layer increase by 100 mm water equivalent (w.e.). However, the main reason for the Altai mountains' deglaciation is an increase of downward solar radiation flux, which amounted to 5 W/m2 per decade and increased the melting layer by 365 mm w.e. per year. A positive trend in net radiation agrees well with a decrease in cloud amount, which is associated with an increase in the moisture divergence flux and geopotential height and with the weakening of zonal winds in the middle troposphere. [ABSTRACT FROM AUTHOR]

Onosma fuyunensis, a new species of Boraginaceae from northern Xinjiang, China, is described and illustrated here. Onosma fuyunensis is similar to O. simplicissima and O. gmelinii; it differs in having a particularly bristly indumentum, unbranched stems, white and yellow corollas, anthers united only at base, and nutlets with a stipitate cicatrix. An updated key to the species of Onosma from Xinjiang and Altai Mountains is also provided. [ABSTRACT FROM AUTHOR]

Located in the intermediate zone between the taiga forests in Siberian Plain and the deserts in Central Asia, the Altai Mountains are of scientific concern about Holocene climate change in the past decades. However, researches about modern climate changes are relatively scarce in the Altai Mountains. In this study, temporal- spatial changes of air temperature and precipitation were investigated systematically in the Altai Mountains based on fifteen meteorological records over the period of 1970–2015. The Altai Mountains experienced a rapid warming trend with a rate of 0.41°C/decade and an insignificantly wetting trend at a rate of 4.82 mm/decade during 1970–2015. The magnitude of temperature trend was negatively correlated with elevation in cold season (spring and winter), whereas that was positively correlated with elevation in warm season (summer and autumn). The cyclonic anomalies to the northwest and an anticyclonic anomalies to the southeast blocked the southward cold air and then provided the favorable condition for an increasing precipitation via the southwesternly wind in the Altai Mountains. [ABSTRACT FROM AUTHOR]

Recent anthropological and archaeological studies have established the significance of the Altai Mountains prehistoric sites, which illustrate complex peopling events. In this paper, we use the chaîne opératoire techno-economic approach to describe the reduction sequences from layers 5 and 3 of Ust'-Kanskaya cave, Gorny Altai, Russia. The Levallois concept is attested in both layers by the presence of cores, flakes, points and blades. However, the majority of the products do not correspond to the cores, which implies a shift at some point of the reduction sequence. Shorter reduction sequences that do not demand such a high degree of predetermination have also been identified. The two layers display similar technological features and can both be associated with the Levalloiso-Mousterian variant of the Altai Middle Palaeolithic. [ABSTRACT FROM AUTHOR]

We here preset a result of high-resolution pollen data of a lacustrine-peat sediment core from Yushenkule (YSKL) Peat, southern Altai Mountains, northwestern China. We aim to reconstruct the palaeovegetation and palaeoclimate variations in the southern Altai Mountains and further evaluate the role of autogenic process of the raised bog itself in driving the local vegetation dynamics. The pollen data of YSKL core-2 show two major vegetation stages in YSKL Peat area and the surrounding areas during the data-covering period. During the stage lasting from ~4870 to ~2550 cal. yr BP, regional vegetation was dominated by desert steppe and local vegetation in YSKL Peat was characterized by Artemisia -dominated mountain steppe. During the stage lasting from ~2550 to ~700 cal. yr BP, regional vegetation was characterized by Artemisia -dominated steppe and local vegetation in YSKL Peat was characterized by Cyperaceae-dominated wetland herbs. The Ar/Am (Artemisia /Amaranthaceae) ratio-indicated moisture increasing trend of southern Altai Mountains can attribute to the combined effects of decreased temperature and increased precipitation. The lithologic transition from lake to peat of YSKL core-2 can be explained by invoking the variations in the areal extent of ice covers in the Altai Mountains. [ABSTRACT FROM AUTHOR]

Mass-spectrometry with inductively coupled plasma was applied to determine the dissolved forms of 26 elements in the water of lakes of the Mul'tinskii Basin. Specific features were identified in the formation of water chemistry in the water bodies of high-mountain Altai territories which suffer little anthropogenic impact. Water quality and the effect of natural factors on it were assessed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A moisture record over the past ~2200 years in the southern Altai Mountains. • The moisture variations in the Altai Mountains have been paced by precipitation variations. • The precipitation variations in the Altai Mountains were primarily related to the NAO variations. Abstract A ∼2200-year moisture history of the southern Altai Mountains (i.e., Chinese Altai) was established based on peat δ13C celluose data obtained at Yushenkule (YSKL) Peat. Generally speaking, the moisture record from YSKL Peat exhibits a "cool-wet" DACP (Dark Age Cold Period from ∼500 to ∼800 CE), a "warm-dry" MWP (Medieval Warm Period from ∼800 to ∼1200 CE), a "cool-wet" LIA (Little Ice Age from ∼1200 to ∼1900 CE), and a "warm-dry" CWP (Current Warm Period since ∼1900 CE). But, RWP (Roman Warm Period from prior to ∼100 CE to ∼500 CE) is an exception (i.e., "warm-wet"). If the heat-water combinations within those major temperature-change events are further examined, the "warm-dry/cool-wet" generalization collapses. The comparisons between the variations in the peat δ13C celluose -based moisture obtained from YSKL Peat and the variations of reconstructed climatic variables in the referenced sequences suggest that the moisture variations in the Altai Mountains have been basically controlled by the precipitation that was primarily modulated by the NAO variations. [ABSTRACT FROM AUTHOR]

In this publication, the discussion is focused on issues related to the stratigraphy and chronology of the Karama Lower Paleolithic site in the Altai Mountains in light of the article "Debatable Aspects of Initial Human Colonization of Siberia and Age of the Karama Site in the Altai Mountains" by V.S. Zykin, V.S. Zykina, and L.G. Smolyaninova published in Stratigraphy and Geological Correlation in 2016. [ABSTRACT FROM AUTHOR]

The location of the Altai Mountains at the limits of both the Pacific and Atlantic influences implies that this mountain range is an important climatic boundary. Based on pollen data of 188 samples of a 390-cm core from Narenxia Peat in the southern Altai with a chronologic support of 11 accelerator mass spectrometry (AMS) dates, we reconstructed the Holocene climatic change at Narenxia Peat. The reconstruction revealed five stages of climatic change: a cold and dry latest deglacial (prior to ~11,500 cal. yr BP), a warm and wet early-Holocene (~11,500 to ~7000 cal. yr BP), a considerably cooled and dried middle Holocene (~7000 to ~4000 cal. yr BP), a resumed warm and wet late-Holocene (~4000 to ~1200 cal. yr BP), and a relatively cool and dry latest Holocene (past ~1200 years). The reconstructions of mean annual temperature (MAT) and mean annual precipitation (MAP) from Narenxia Peat well resemble the reconstructions of North Atlantic Oscillations (NAO) and El Niño–Southern Oscillations (ENSO). The resemblance implies that the Holocene millennial-scale changes in MAT and MAP in the Altai might have been causally associated with the variations in NAO and ENSO. [ABSTRACT FROM AUTHOR]

Debatable aspects of age, stratigraphic position, and natural conditions of the oldest stratified Early Paleolithic Karama site in the Altai Mountains are critically revised. The extensive geological, stratigraphic, and paleontological data allow the sufficiently well-substantiated assumption that accumulation of the Karama Formation and existence of the Early Paleolithic Karama site correspond to a long period of climate warming in the Early Pleistocene correlated with the Tiglian of northwestern Europe lasting from 2.23 to 1.59 Ma. The age model proposed for the formation of the Quaternary sequence in the Anui River valley, which includes the artifact-containing deposits of the Karama site, seems to be the most probable one proceeding from interpretation of available data on the geological structure, stratigraphy, paleomagnetism, and paleontological and lithological properties of Upper Cenozoic sequences observable both in the Anui River valley and in Siberian areas adjacent to the Altai mountainous region. [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]

The article discusses Altaian artistic culture from the standpoint of historical localities. Topics covered include the acquisition by the local historical object of an independent ontological status, and the ontological object's implementation of the existential content of historical time and Altai landscape complex. Also noted are a curious Siberian letter (1827), and works of G.D. Grebenschikov and V.M. Shukshin.

The article reports on the variety and scope of museum life in Altai Region as of 2014. Topics discussed include museum documentation, and the coverage of nature, history, ethnography and art development in both traditional, and highly specialized museums like church and memorial repositories. Also mentioned are the displays in such museums as the Altai State Museum of Local History, and the Historical Museum of Mining Development.

The article discusses the world view of the Altai people as of 2014. Topics covered include the cultural and religious interaction amongst various Altai inhabitants for thousands of years, Altaian mythology and iconography, and the tolerant co-existence of Altai pagans with Buddhism and Christianity. Also explored are the beliefs of Burhanism and shamanism, and the possible unification of Altaians by the doctrine of Tengrianism.

The article discusses the universal mythological constant World Mountain Sumeru of Central Asian nations. Topics covered include the geographical, historical and cultural realities of the Altai, and the presentation of the birth of the world in myths as an appearance from waters of a primeval ocean of a primeval mountain. Also noted is the echoing by surviving poetical images of the original myth on the origin of the world.

The article discusses civilized mankind's ecological consciousness development based on traditional Altai doctrine. Topics covered include the need to change modern man's regard for the environment, the view of all cosmic space as a living organism, and an analysis of space ecology from the viewpoints of Altai religious doctrine and of modern science. Also noted is the connection in the Sacred Lands of all information grids in the planetary sphere of mind.

The article offers a poetic view of Altai as a holistic and complex cultural phenomenon as of 2014. Topics discussed include the spatial, geographical, cultural, and historical sense of the region, and the significant developing power, intercultural contacts, and spiritual potential of Oecumene of Altai Region. Also mentioned is the possible definition of Altai culture as a sacred phenomenon of the world that can develop intercultural dialogue at the present time.

The article discusses Altai as a Eurasian melting pot wherein varied ethnic groups, cultures, and religions conglomerate as of 2014. Topics covered include the historical traditions of international cooperation in Altai, its continuing spirit of unity based on common spiritual values, and its need for mutual solutions for current common problems. Also mentioned are the main problem of the formation of the Eurasian person and the values of such a personality.

The article explores the preservation of national cultures in a globalized world and the need to understand cultural developments as of 2014. Topics discussed include their application in the Altai region and its neighboring states, and the importance of a different approach on unique regional features to develop a cultural philosophy. Also mentioned is the engagement of the heuristicity of Eurasian culture concept in addressing this challenge.

The article traces the old North Silk Route to Sumeru, Altai, Siberia as of 2014. Topics covered include Altai's description as The Golden Mountains with its generous waterways and snowy peaks, and rich flora and fauna, its hosting of varied ethnic and linguistic groups throughout history, and its industries and political system. Also given are a narrative and photographs on the pilgrimage along the Silk Route.

The article discusses the specific geo-ecological and social functions of Altai as of 2014. Topics covered include the country's location on the borders of Russia, Mongolia, China and Kazakhstan, its isolation arising from its complicated orography and characteristic climate and topography, and its continental function as a regulator and redistributor of air and water masses. Also mentioned are Altai's low population count, poor socio-economic development, and attraction of tourists.

An introduction is presented in which the editor discusses the analyses of various aspects of life by scientists living in the Altai including the nature and culture of the Altai, the environment and the economy, and spiritual values and meanings.

Abstract: The Altay orogenic belt (AOB), situated in the middle part of the Central Asian Orogenic Belt (CAOB), is one of the most important metallogenic belts in China. The Kangbutiebao Formation is a Late Paleozoic stratigraphic unit that hosts many important iron and Pb–Zn deposits. The Kangbutiebao Formation consists of intercalated volcanic and sedimentary rocks that have undergone regional greenschist to lower amphibolite facies metamorphism, and mainly outcrops in three NW-trending fault-bounded volcano–sedimentary basins, including the Maizi, Kelang, and Chonghuer basins. SHRIMP analyses of zircons from three metarhyolites of the Kangbutiebao Fm. in the Kelang Basin yield weighted mean 206Pb/238U ages of 412.6±3.5 Ma, 408.7±5.3 Ma and 406.7±4.3 Ma, respectively, which can be interpreted as the eruption age of the Kangbutiebao silicic volcanic rocks in the Kelang Basin. These ages indicate that the Kangbutiebao Formation was formed during the Late Silurian to Early Devonian. They also demonstrate that the deposits hosted in the Kangbutiebao Formation were formed after 412–407 Ma. They play a key role in understanding the Paleozoic tectonic evolution and metallogenesis of the southern margin of the Chinese AOB. [Copyright &y& Elsevier]

Abstract: Dzhangyskol is a small lake of glacial origin in the central part of the Altai Mountains in southern Siberia. Pollen stratigraphies and chronologies of two cores record the vegetational development of the area from the Late Glacial treeless landscape to the forest and steppe of today. The modern lake is a remnant of a much larger ice-dammed lake, which was reduced in size and then temporarily drained after diversion of the inflowing mountain meltwater stream, which had low δ 18O values. The dry lake floor allowed development of permafrost and small pingos (frozen mounds of lake sediments). With the onset of greater climatic humidity in the mid-Holocene, the input of local water with higher δ 18O caused a rise in lake level, drowning the earlier pingos. Growth of a broad fen on the margin of the lake led to formation of a modern pingo complex. [Copyright &y& Elsevier]

The Altai Mountains are a key area for understanding the development of the Altai Tectonic Collage and accretionary orogen. However, the orogenic processes, particularly their early stage, have not been well understood. In this work, we undertake zircon U-Pb dating of six Paleozoic synorogenic plutons in order to better define the early magmatic and tectonic evolution of the Chinese Altai Mountains. The results revealed three Paleozoic granitic plutonic events at ca. 460, 408, and 375 Ma. These ages, along with the structural patterns of the plutons, suggest two periods of regional deformation, 460–410 Ma and 410–370 Ma. The granitoids mainly follow the tholeiitic and calc-alkaline trends and are mostly I type. Sr-Nd isotopic analyses indicate that the sources of the granitoids contain both old continental and younger (juvenile) mantle-derived components. Chemical, isotopic, and structural features suggest that the plutons were formed mainly in continental arc settings and that the subduction and accretion processes began at ca. 460 Ma and culminated at ca. 408 Ma. Thus, the Altai orogen was mainly built up during early-middle Paleozoic time, rather than during late Paleozoic time. Furthermore, the southern Altai terrane comprises not only Silurian to Devonian island arcs but also old continental fragments. With these new constraints, we present a new model to account for the tectonic evolution of the Altai orogen. This model proposes that early-middle Paleozoic Altai orogenic processes could have experienced formation of an active continental margin, the splitting of this margin to form a back-arc oceanic basin, and the final closing of the back-arc basin. Consequently, the opening and closure of back-arc basins along active margins is probably a common process in the central Asian accretionary orogen. [ABSTRACT FROM AUTHOR]

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]

Studies the Cenozoic construction of the Mongolian Altai, a Cenozoic intercontinental and intraplate mountain ranges in Mongolia. Regional physiography; Major faults and historic seismicity; Mechanism of mountain building in the Western Altai.

The glacier snowline altitude (SLA) at the end of the melt season is an indicator of the glacier equilibrium line altitude and can be used to estimate glacier mass balance and reconstruct past climate. This study analyzes the spatiotemporal variability in glacier SLA across High Mountain Asia, including the Altai Mountains, Karakoram Mountains, Western Himalayas, Gongga Mountains, Tian Shan, and Nyainqentanglha Mountains, over the past 30 years (1989–2019) to better elucidate the state of these mountain glaciers. Remote-sensing data are processed to delineate the glacier SLA across these mountainous regions, and nearby weather station data are incorporated to determine the potential relationships between SLA and temperature/precipitation. The mean SLAs across the Altai and Karakoram mountains ranged from 2860 ± 169 m to 3200 ± 152 m and from 5120 ± 159 m to 5320 ± 240 m, respectively, with both regions experiencing an average increase of up to 137 m over the past 30 years. Furthermore, the mean glacier SLAs across the Western Himalayas and Gongga Mountains increased by 190–282 m over the past 30 years, with both regions experiencing large fluctuations. In particular, the mean glacier SLA across the Western Himalayas varied from 4910 ± 190 m in 1989 to 5380 ± 164 m in 2000, and that across the Gongga Mountains varied from 4960 ± 70 m in 1989 to 5330 ± 100 m in 2012. Correlation analyses between glacier SLA and temperature/precipitation suggest that temperature is the primary factor influencing glacier SLA across these High Mountain Asia glaciers. There is a broad increase in glacier SLA from the Altai Mountains to the Karakoram Mountains, with a decrease in glacier SLA with decreasing latitude across the Himalayas; the maximum SLA occurs near the northern slopes of the Western Himalayas. The glacier SLA is lower on the eastern side of the Tibetan Plateau and exhibits a longitudinal distribution pattern. These results are expected to provide useful information for evaluating the state of High Mountain Asia glaciers, as well as their response and feedback to climate change. [ABSTRACT FROM AUTHOR]

This study reconstructed the vegetation dynamics and associated climate change of the past ~4100 years based on the pollen data from a short peat core (i.e., KLSZ-2) in Kelashazi Peat (48.12°N, 88.37°E, 2422 m a.s.l.) in the Altai Mountains. The reconstructed vegetation and climate were then stacked with those from a longer peat core (i.e., KLSZ-1) to evaluate the vegetation dynamics and associated climate change of the entire Holocene and to examine the δ13C cellulose - and δ18O cellulose -based temperature reconstructions in the same peat. This study shows that vegetation in Kelashazi valley was dominated by alpine meadows before ~8200 cal. yr BP, by taiga forests at ~8200-~5600 cal. yr BP, and by an expansion of alpine meadows since ~5600 cal. yr BP. This study also examined the vegetation dynamics and associated climate in the context of the entire Altai Mountains and the surrounding areas. Our examination suggests that the forest expansion in high elevations was initiated when the temperature reached a threshold level during the early Holocene, and the forest expansion in low elevations (i.e., below the down treeline) was initiated when the moisture reached a threshold level during the middle Holocene or even late Holocene. It is also notable that the forest expansion at low elevations appears to have been longitude-dependent, i.e., time transgressive eastward. A possible mechanism to explain the longitude-dependency is that a gradual shrinking trend of the Siberian High linked to the Holocene increase in winter insolation allowed the domination of the water vapor-enriched Westerlies to gradually encroach eastward. • Late Holocene vegetation changes were reconstructed in the southern Altai Mountains. • Holocene forest expansion at high elevations was initiated by threshold-level temperature. • Holocene forest expansion at low elevations was initiated by threshold-level moisture. • Forest expansion at low elevations appears longitude-dependent. [ABSTRACT FROM AUTHOR]

Due to their effects on snow/ice melting in mountains and evaporation in basins, temperature variations are an important influence on the hydrological cycle and water resources in arid Central Asia (ACA). We present independently-dated peat brGDGTs-based MBT′/MBT′ 5ME records from an alpine Sahara sand peatland (SSP) in the southern Altai Mountains, in ACA. During the past ~11 kyr, the SSP MBT′ and MBT′ 5ME profiles exhibit consistently increasing trends and they are significantly positively correlated. Using a global peat-specific MBT′ 5ME -tempeature calibration, the long-term Holocene warming trend indicated by the quantitative SSP mean annual temperature (MAT peat) reconstruction is supported by the peat α-cellulose δ13C summer temperature record from the SSP, and by an independent peat α-cellulose δ18O winter temperature record from a nearby site (i.e. temporal validation). The increasing trends are also evident in Holocene peat MBT′ records from the Hongyuan (HY) peatland in the NE Tibetan Plateau, and in the Shuizhuyang (SZY) peatland in SE China. Notably, both the MBT′ data of the surface samples and the averaged MBT′ data of the Holocene peat cores are consistent with the modern spatial temperature gradient at the SSP, HY and SZY (i.e. spatial validation). This evidence demonstrates the temperature significance of peat MBT′/MBT′ 5ME records. The long-term Holocene warming trend indicated by the SSP MBT′/MBT′ 5ME records is supported by recently-acquired Holocene temperature records from the Eurasian continent. This trend is the opposite to the traditional viewpoint of a long-term Holocene cooling trend, and it indicates that more effort is needed to obtain a reliable Holocene temperature history. • The Holocene peat MBT′/MBT′ 5ME records from Altai Mountains in arid Central Asia • The peat MBT′/MBT′ 5ME records indicate the Holocene temperature history. • The long-term Holocene warming trend is indicated by the peat MBT′/MBT′ 5ME records. • The Holocene warming trend is supported by recent records from Eurasian continent. [ABSTRACT FROM AUTHOR]

Tectonic activity and climate change are regarded as two important driving forces on the evolution of large-scale drainage. The evolution of the Irtysh River and Ulungu River, two large-scale drainage systems in the northern Junggar Basin, can provide a key constraint on the uplift of the Altai Mountains and Central Asian aridification. However, we know little about the evolution of these two large-scale rivers. This study presents new detrital zircon U–Pb data from the late Oligocene to late Miocene sedimentary sequences and modern river sediments to reconstruct Cenozoic paleo-drainage evolution in the northern Junggar Basin. The detrital zircon U–Pb results show a single major population at 460-360 Ma, which is mainly derived from the Altai Mountains, for late Oligocene and early Miocene sequences, but two populations at 460-360 Ma and 340-200 Ma, which are mainly from the Altai Mountains and East Junggar terrane, for middle and late Miocene sequences. Our provenance study argues that the Irtysh River and Ulungu River in their modern extent did not exist prior ~18 Ma when the Altai Mountains allowed southward-flowing rivers to transport sediments into the inner Junggar Basin directly. The provenance shift in northern Junggar Basin at 17–18 Ma represents the progressive drainage expansion of the Ulungu River, evolving from relatively small rivers confined to the eastern Junggar Basin to a near-modern large-scale drainage system, due to the rapid uplift in the East Junggar terrane and eastern Altai Mountains in early Miocene. After ~6 Ma, the Irtysh River experienced a progressive drainage expansion, captured the southward-flowing tributaries of the Ulungu River and formed modern drainage pattern. Our study supports the initiation of exhumation before late Oligocene and a local tectonic uplift in early Miocene in Altai Mountains, which imply a complex deformation process in the Central Asia. • Paleo-drainage evolution in the northern Junggar Basin during the last ~27 Myr. • The relative roles of tectonic activity and climate change in drainage evolution. • A relatively high topography in late Oligocene in Altai Mountains. • Local tectonic uplift forces the drainage expansion of Ulungu River at 17–18 Ma. [ABSTRACT FROM AUTHOR]

In this work, we present a whole system model of megafloods from catastrophic ice-dam failure in the late Pleistocene that comprises the study of the dynamics of the glacial lake, the propagation of the flood wave downstream of the dam, and an approximation to the ice breach process. The ice-dam incision rate was simply considered an unknown constant, which was varied systematically to best fit the maximum altitude of the simulated water surface and the paleostage indicators in the downstream valley during the transient megaflood. Hence, the hydrograph resulting from the breach of the ice dam was not prescribed but was an output of the paleohydraulic reconstruction. By considering two possible configurations of the breach in the ice dam, i.e. full or partial removal of the ice, we constrained the incision rate in the narrow range of 28 − 42 m ⋅ h−1. Two connected glacial lakes, Kuray and Chuja, released 95% of the stored water volume (i.e., 564 km3) in 33.8 hours. A peak discharge of 10.5 M m3 ⋅ s−1 was required to form numerous giant bars and run-up deposits in the Chuja and Katun valleys. The peak streamflow occurred after 11 h when 45% of the available lake volume had been evacuated from the Kuray and Chuja basins. Further verification of the reconstructed megaflood was achieved by studying the computed hydraulic conditions during the lake draining that justify the existence and orientation of several fields of subaqueous gravel-dunes in the glacial lake. Complex spatiotemporal patterns during the recession stage of the flood built most of the fields of bedforms. In terms of nondimensional parameters, the Froude and Shields numbers that formed the dune fields were similar to those observed in large sandy rivers, but the flow was undoubtedly unsteady and two-dimensional. We conclude by noting that the extensions of the simulated area cannot be cropped or analysed by independent parts in order to predict the formation of the most relevant geological records due to the unsteady, two-dimensional nature of the flow motion and the development of backwater effects in the drainage network. Lastly, the paleohydrological reconstruction of a megaflood has helped not only to infer the dynamics of the event but also to retrodict the mean parameters of the ice-dam failure mechanism. [ABSTRACT FROM AUTHOR]

Mongolia's Geoheritage is of exceptional value, but little known to the outside world. In this presentation, I make the case that the northeastern Gobi Altai region in central Mongolia contains outstanding geological diversity and geoheritage and is worthy of consideration for Global Geopark status under the UNESCO umbrella.The region under consideration encompasses the southern slopes of the Hangay Dome, the easternmost Valley of Lakes and the basins and ranges of the northeastern Gobi Altai. The area is arid to semi-arid throughout with excellent rock exposures of a wide variety of igneous, metamorphic and sedimentary strata. The geology and landscape record a complex Precambrian-Quaternary geological evolution. The region is also tectonically active as expressed by Holocene fault scarps, co-seismic landslides, youthful mountain ranges flanked by aggrading alluvial fan systems, and internally drained fault-bound basins. Within a rectangular area of approximately 30,000 km2, there is a remarkable concentration and variety of world-class geological and geomorphological features in the NE Gobi Altai region that are related to: 1) active tectonics, 2) Neogene volcanism, 3) arid-land sedimentary systems, 4) dinosaur and mammal paleontology, 5) mass wasting, and 6) bedrock geology. In this presentation, I describe and show individual features in each of these categories. In addition, throughout the region, there are important geological influences on the distribution of human settlements and endangered wildlife that merit description and recognition. Mining, hydrocarbon exploration and increasing numbers of international tourists pose a growing threat to the region's unique geoheritage, spectacular natural scenery, biodiversity and traditional nomadic culture. [ABSTRACT FROM AUTHOR]

Located in Asia where Russia, China, Mongolia, and Kazakhstan share a border, the Altai Mountains are composed by high ranges peaking at 4,506 m (Belukha), still glaciated large plateaus and deep valleys. With more than 1000 km², the Altai glaciers represent 50 % of the glaciated area of North Asia. Although because of repeated occurrences of glacial megafloods during the Pleistocene have been intensively studied in Russian Altai, the chronology and extent of its glaciations are poorly understood compared to other Central Asian regions.In relation with archaeological researches developed by the Russian-French team ARTEMIR, we investigated the upper Kalguty basin located in the south-eastern part of the Ukok Plateau, Russian Altai. Along the border with Mongolia, the elevation of this very dry area (100 mm/a) ranges from 2300 to 3500 m. Although current glacier area is < 0.25 km², many glacial landforms allow reconstructing past glaciations in the upper Kalguty basin. A detailed geomorphological study was carried out on the field in July 2015, and rock samples were taken on scoured bedrock and erratic boulders at one key site for surface exposure dating using in situ-produced cosmogenic nuclides.The maximal extent of the Kalguty valley glacier in the upper basin occurred shortly before 20.9 ka. As evidenced by moraines and kame terraces located higher on one valley side, larger and earlier, but not dated, glaciations occurred prior to the ~21 ka Kalguty Glacier advance. On the other hand, three morainic complexes testify to smaller advances corresponding to a reduced Kalguty glacier and two smaller valley glaciers. Reconstructed ELAs of these former glaciers were used to infer their Late Glacial extents ages and the corresponding regional palaeoclimatic conditions. The results regarding the chronology and extent of the Kalguty Basin glaciations since the LGM are discussed by relating them to other regional studies in the Altai Mountains and Central Asia. [ABSTRACT FROM AUTHOR]