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G Q Zhao - One of the best experts on this subject based on the ideXlab platform.
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the Last Glaciation in the headwater area of the xiaokelanhe river chinese altai evidence from 10be exposure ages
Quaternary Geochronology, 2020Co-Authors: Guocheng Dong, Weijian Zhou, Li Zhang, G Q ZhaoAbstract:Abstract The timing and extent of the Last Glaciation in the Altai Mountains are key to understanding climate change in this critical region. However, robust glacial chronologies are sparse across the Altai Mountains, especially in the Chinese Altai, impeding the correlation of glacial events and examination of the possible climate forcing mechanisms. Here, we report twenty new 10Be exposure-ages obtained from two moraines in the headwater area of the Xiaokelanhe River, Chinese Altai. The inner latero-frontal moraine yields exposure-ages ranging from 16.60 ± 1.00 to 20.41 ± 1.15 ka (n = 5), reflecting a limited advance during the global Last Glacial Maximum (LGM). The morpho-stratigraphically older moraine remnants have exposure-ages of 14.36 ± 0.94–38.98 ± 2.23 ka (n = 15). The tentatively determined moraine age of 34.10 ± 4.99 ka suggests that the local LGM in the Xiaokelanhe River likely occurred during Marine Isotope Stage (MIS) 3 or earlier. From a compilation of the 20 new, and 79 previously published exposure-ages, we observe at least three distinct glacial events during the Last glacial, with the local LGM occurring prior to MIS 2. A comparison between the timing of glacial activities and climate proxies suggests a potential combination of summer solar insolation, North Atlantic climate oscillations, and atmospheric CO2 levels, as triggers for glacial movements during the Last glacial cycle. Precipitation delivered by the mid-latitude westerlies may have also contributed to glacial advances during MIS 3. These correlations remain tentative however, due to limited chronological control.
Anthony J Stuart - One of the best experts on this subject based on the ideXlab platform.
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woolly mammoth mammuthus primigenius blum and its environment in northern europe during the Last Glaciation
Quaternary Science Reviews, 2011Co-Authors: Pirkko Ukkonen, Laura Arppe, K Aarissorensen, Robert S Sommer, Lembi Lõugas, Linas Daugnora, Peter U Clark, Heikki Seppa, Adrian M Lister, Anthony J StuartAbstract:Abstract Woolly mammoths were large, herbivorous, cold-adapted mammals of the Late Pleistocene. The diet and habitat requirements of the species set certain constraints on the palaeoenvironments it could occupy. The relationship between the mammoth’s shifting range and changing environments can be explored using independent data on ice sheet configuration, temperature, and vegetation, provided the locality and age of the fossil remains can be validated. Here we present a comprehensive record of occurrence of the woolly mammoth in the circum-Baltic region of northern Europe during the Last Glaciation, based on a compilation of radiocarbon-dated remains. The record shows that the mammoth was widespread in northern and north-eastern Europe during Marine Isotope Stage 3 (MIS 3), at 50,000–30,000 calibrated years ago (50–30 ka). The presence of the species up to 65°N latitude supports the restriction of the Scandinavian Ice Sheet (SIS) during MIS 3. The widest distribution range round 30 ka was followed by a decline that led to the disappearance of mammoths from the area during the maximum extent of the SIS, from 22 to 18 ka. The woolly mammoth re-colonized the Baltic region and southern Scandinavia after the onset of the late-glacial deGlaciation at 17 ka. The late-glacial record suggests a markedly fluctuating population changing its range in tune with the rapid environmental changes. The Last appearance of mammoth in our study region was in Estonia during the Younger Dryas (Greenland Stadial 1; GS1) at about 12 ka. The two major periods of occurrence during MIS 3 and the late-glacial stadial suggest that mammoth had a wide tolerance of open to semi-open tundra and steppe-tundra habitats with intermediately cold climate, whereas the 22–18 ka disappearance suggests a major southward and/or eastward retreat in response to extremely cold, glacial conditions near the SIS margin. The final regional extinction correlates with the re-forestation during the rapid warming at the Younger Dryas–Holocene boundary.
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woolly mammoth mammuthus primigenius blum and its environment in northern europe during the Last Glaciation
Quaternary Science Reviews, 2011Co-Authors: Pirkko Ukkonen, Laura Arppe, K Aarissorensen, Robert S Sommer, Lembi Lõugas, Linas Daugnora, Peter U Clark, Heikki Seppa, Adrian M Lister, Anthony J StuartAbstract:Abstract Woolly mammoths were large, herbivorous, cold-adapted mammals of the Late Pleistocene. The diet and habitat requirements of the species set certain constraints on the palaeoenvironments it could occupy. The relationship between the mammoth’s shifting range and changing environments can be explored using independent data on ice sheet configuration, temperature, and vegetation, provided the locality and age of the fossil remains can be validated. Here we present a comprehensive record of occurrence of the woolly mammoth in the circum-Baltic region of northern Europe during the Last Glaciation, based on a compilation of radiocarbon-dated remains. The record shows that the mammoth was widespread in northern and north-eastern Europe during Marine Isotope Stage 3 (MIS 3), at 50,000–30,000 calibrated years ago (50–30 ka). The presence of the species up to 65°N latitude supports the restriction of the Scandinavian Ice Sheet (SIS) during MIS 3. The widest distribution range round 30 ka was followed by a decline that led to the disappearance of mammoths from the area during the maximum extent of the SIS, from 22 to 18 ka. The woolly mammoth re-colonized the Baltic region and southern Scandinavia after the onset of the late-glacial deGlaciation at 17 ka. The late-glacial record suggests a markedly fluctuating population changing its range in tune with the rapid environmental changes. The Last appearance of mammoth in our study region was in Estonia during the Younger Dryas (Greenland Stadial 1; GS1) at about 12 ka. The two major periods of occurrence during MIS 3 and the late-glacial stadial suggest that mammoth had a wide tolerance of open to semi-open tundra and steppe-tundra habitats with intermediately cold climate, whereas the 22–18 ka disappearance suggests a major southward and/or eastward retreat in response to extremely cold, glacial conditions near the SIS margin. The final regional extinction correlates with the re-forestation during the rapid warming at the Younger Dryas–Holocene boundary.
Li Zhang - One of the best experts on this subject based on the ideXlab platform.
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the Last Glaciation in the headwater area of the xiaokelanhe river chinese altai evidence from 10be exposure ages
Quaternary Geochronology, 2020Co-Authors: Guocheng Dong, Weijian Zhou, Li Zhang, G Q ZhaoAbstract:Abstract The timing and extent of the Last Glaciation in the Altai Mountains are key to understanding climate change in this critical region. However, robust glacial chronologies are sparse across the Altai Mountains, especially in the Chinese Altai, impeding the correlation of glacial events and examination of the possible climate forcing mechanisms. Here, we report twenty new 10Be exposure-ages obtained from two moraines in the headwater area of the Xiaokelanhe River, Chinese Altai. The inner latero-frontal moraine yields exposure-ages ranging from 16.60 ± 1.00 to 20.41 ± 1.15 ka (n = 5), reflecting a limited advance during the global Last Glacial Maximum (LGM). The morpho-stratigraphically older moraine remnants have exposure-ages of 14.36 ± 0.94–38.98 ± 2.23 ka (n = 15). The tentatively determined moraine age of 34.10 ± 4.99 ka suggests that the local LGM in the Xiaokelanhe River likely occurred during Marine Isotope Stage (MIS) 3 or earlier. From a compilation of the 20 new, and 79 previously published exposure-ages, we observe at least three distinct glacial events during the Last glacial, with the local LGM occurring prior to MIS 2. A comparison between the timing of glacial activities and climate proxies suggests a potential combination of summer solar insolation, North Atlantic climate oscillations, and atmospheric CO2 levels, as triggers for glacial movements during the Last glacial cycle. Precipitation delivered by the mid-latitude westerlies may have also contributed to glacial advances during MIS 3. These correlations remain tentative however, due to limited chronological control.
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The Last Glaciation in the headwater area of the Xiaokelanhe River, Chinese Altai: Evidence from Be-10 exposure-ages
'Elsevier BV', 2020Co-Authors: Dong Guocheng, Li Zhang, Zhou Weijian, Fu Yunchong, Zhao Guoqing, Li MingAbstract:The timing and extent of the Last Glaciation in the Altai Mountains are key to understanding climate change in this critical region. However, robust glacial chronologies are sparse across the Altai Mountains, especially in the Chinese Altai, impeding the correlation of glacial events and examination of the possible climate forcing mechanisms. Here, we report twenty new Be-10 exposure-ages obtained from two moraines in the headwater area of the Xiaokelanhe River, Chinese Altai. The inner latero-frontal moraine yields exposure-ages ranging from 16.60 +/- 1.00 to 20.41 +/- 1.15 ka (n = 5), reflecting a limited advance during the global Last Glacial Maximum (LGM). The morpho-stratigraphically older moraine remnants have exposure-ages of 14.36 +/- 0.94-38.98 +/- 2.23 ka (n = 15). The tentatively determined moraine age of 34.10 +/- 4.99 ka suggests that the local LGM in the Xiaokelanhe River likely occurred during Marine Isotope Stage (MIS) 3 or earlier. From a compilation of the 20 new, and 79 previously published exposure-ages, we observe at least three distinct glacial events during the Last glacial, with the local LGM occurring prior to MIS 2. A comparison between the timing of glacial activities and climate proxies suggests a potential combination of summer solar insolation, North Atlantic climate oscillations, and atmospheric CO2 levels, as triggers for glacial movements during the Last glacial cycle. Precipitation delivered by the mid-latitude westerlies may have also contributed to glacial advances during MIS 3. These correlations remain tentative however, due to limited chronological control
Guocheng Dong - One of the best experts on this subject based on the ideXlab platform.
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the Last Glaciation in the headwater area of the xiaokelanhe river chinese altai evidence from 10be exposure ages
Quaternary Geochronology, 2020Co-Authors: Guocheng Dong, Weijian Zhou, Li Zhang, G Q ZhaoAbstract:Abstract The timing and extent of the Last Glaciation in the Altai Mountains are key to understanding climate change in this critical region. However, robust glacial chronologies are sparse across the Altai Mountains, especially in the Chinese Altai, impeding the correlation of glacial events and examination of the possible climate forcing mechanisms. Here, we report twenty new 10Be exposure-ages obtained from two moraines in the headwater area of the Xiaokelanhe River, Chinese Altai. The inner latero-frontal moraine yields exposure-ages ranging from 16.60 ± 1.00 to 20.41 ± 1.15 ka (n = 5), reflecting a limited advance during the global Last Glacial Maximum (LGM). The morpho-stratigraphically older moraine remnants have exposure-ages of 14.36 ± 0.94–38.98 ± 2.23 ka (n = 15). The tentatively determined moraine age of 34.10 ± 4.99 ka suggests that the local LGM in the Xiaokelanhe River likely occurred during Marine Isotope Stage (MIS) 3 or earlier. From a compilation of the 20 new, and 79 previously published exposure-ages, we observe at least three distinct glacial events during the Last glacial, with the local LGM occurring prior to MIS 2. A comparison between the timing of glacial activities and climate proxies suggests a potential combination of summer solar insolation, North Atlantic climate oscillations, and atmospheric CO2 levels, as triggers for glacial movements during the Last glacial cycle. Precipitation delivered by the mid-latitude westerlies may have also contributed to glacial advances during MIS 3. These correlations remain tentative however, due to limited chronological control.
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modelling glacier advances and related climate conditions during the Last Glaciation cycle in the kuzigun valley tashkurgan catchment on the north west tibetan plateau
Journal of Quaternary Science, 2014Co-Authors: Guocheng Dong, Baolin PanAbstract:Understanding regional climate during the Last Glaciation cycle (LGC) is far from complete for the north-western Tibetan Plateau. Recent improvements in understanding glacial extents and chronologies in the Tashkurgan catchment, north-west Tibetan Plateau, present an opportunity to estimate the glacial climatic conditions of the LGC. Here we use a coupled mass-balance and ice-flow model to reconstruct glacier advances in the Kuzigun Valley during the LGC and quantify the related climate conditions in the Tashkurgan, Hangdi, and Kuzigun glacial stages for the region. The model results show that the Kuzigun Valley contained ice volumes of 5.713 ± 0.005, 4.874 ± 0.005 and 3.631 ± 0.004 km3 with equilibrium line altitude-lowering values of ∼500, ∼560 and ∼610 m in the three successive glacial stages, respectively. By referencing the climatic δ18O proxy records, we conclude that temperature decreased by 5–8, ∼4 and 140% modern values in the Kuzigun, Hangdi and Tashkurgan glacial stages, respectively. Our climatic estimates for the Kuzigun stage are generally consistent with previous studies that showed the Last Glacial Maximum climate was 4–9 °C colder than today on the Tibetan Plateau. More accurate climate proxies are needed for evaluating our modelled Tashkurgan climatic conditions.
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lake level fluctuations since the Last Glaciation in selin co lake central tibet investigated using optically stimulated luminescence dating of beach ridges
Environmental Research Letters, 2009Co-Authors: Guocheng Dong, Liqiang Wang, Junxiang ZhaoAbstract:This paper presents a preliminary study on lake-level fluctuations since the Last Glaciation in Selin Co (lake), Central Tibet, by dating four groups of beach ridges using optically stimulated luminescence (OSL). The highest/oldest beach ridge group (>100 m higher than the current lake level) is dated back to 67.9 ± 2.4 ka BP, corresponding to the early stage of the Last Glaciation (marine isotope stage (MIS) 4). This date further supports that no plateau-scale ice sheet covered the Tibetan Plateau during the Last Glaciation. The other three groups produce OSL ages of 30.4 ± 2.9 to 18.6 ± 1.7, 12.5 ± 1.6 to 9.2 ± 0.5, and 6.9 ± 0.2 ka BP respectively, most likely corresponding to cold or wet climate periods of the late stage of the Last Glaciation (MIS 2), deGlaciation, and Holocene Hypsithermal. On the plateau scale, these four beach ridge groups are almost synchronous with advances or standstills of Himalayan glaciers, indicating similar climate controls across the central and southern Tibetan Plateau, and being consistent with the conclusion, obtained from nearby ice core records, that this area is affected by the South Asia monsoon. Furthermore, beach ridges are also synchronous with fluvial terraces in the northern Tibetan Plateau, implying common driving forces during their formation. Therefore, some terraces may be formed as a result of climate events rather than being of tectonic origin.
Weijian Zhou - One of the best experts on this subject based on the ideXlab platform.
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the Last Glaciation in the headwater area of the xiaokelanhe river chinese altai evidence from 10be exposure ages
Quaternary Geochronology, 2020Co-Authors: Guocheng Dong, Weijian Zhou, Li Zhang, G Q ZhaoAbstract:Abstract The timing and extent of the Last Glaciation in the Altai Mountains are key to understanding climate change in this critical region. However, robust glacial chronologies are sparse across the Altai Mountains, especially in the Chinese Altai, impeding the correlation of glacial events and examination of the possible climate forcing mechanisms. Here, we report twenty new 10Be exposure-ages obtained from two moraines in the headwater area of the Xiaokelanhe River, Chinese Altai. The inner latero-frontal moraine yields exposure-ages ranging from 16.60 ± 1.00 to 20.41 ± 1.15 ka (n = 5), reflecting a limited advance during the global Last Glacial Maximum (LGM). The morpho-stratigraphically older moraine remnants have exposure-ages of 14.36 ± 0.94–38.98 ± 2.23 ka (n = 15). The tentatively determined moraine age of 34.10 ± 4.99 ka suggests that the local LGM in the Xiaokelanhe River likely occurred during Marine Isotope Stage (MIS) 3 or earlier. From a compilation of the 20 new, and 79 previously published exposure-ages, we observe at least three distinct glacial events during the Last glacial, with the local LGM occurring prior to MIS 2. A comparison between the timing of glacial activities and climate proxies suggests a potential combination of summer solar insolation, North Atlantic climate oscillations, and atmospheric CO2 levels, as triggers for glacial movements during the Last glacial cycle. Precipitation delivered by the mid-latitude westerlies may have also contributed to glacial advances during MIS 3. These correlations remain tentative however, due to limited chronological control.
