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Glacier Relics of the Last Glacial and Holocene Periods Discovered in the Middle-low Mountains of Eastern China: Sedimentary Sequences and Environmental Evolution of Mengshan Mountain in Shandong Province since 80 ka 被引量:8
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作者 WANG Zhaobo WANG Jiangyue +1 位作者 HE Lelong ZHANG Jian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第1期141-151,共11页
The goal of this research study is to describe academic issues which have been debated in the field of Chinese geosciences for a century. In 1922, Jonquei S. Lee(Li Siguang) discovered Quaternary glacial relics at Tai... The goal of this research study is to describe academic issues which have been debated in the field of Chinese geosciences for a century. In 1922, Jonquei S. Lee(Li Siguang) discovered Quaternary glacial relics at Taihang Mountainin eastern China. In 1947, he published his research findings in the magazine Mount Lushan in Glacial Age. The research results had established three Ice Ages: Poyang(Gonzi), Dagu(Minde), and Lushan(Lisi). However, at that time, no Wurm glacial relics of the last Ice Age had been found in Lushan Mountain. Since then, the research team represented by Shi Yafeng, who is considered to be "the father of glaciers in China", questioned Jonquei S. Lee’s research results and concluded that "Professor Jonquei S. Lee’s Quaternary glacier research in Lushan Mountain having misread the debris flow". In 2005, the "middle-low mountains" in eastern China were finally defined as follows: "We clearly and unambiguously believe that there were no glacial activities in the middle-low mountainous areas of eastern China(east of 102° to 104°E;below 3,000 and 2,500 m) during the Quaternary Period". Currently, the long-standing academic debate appears to have come to a conclusion. As of 2015, the author and others began to investigate and study the Quaternary glacial relics in Mengshan Mountain(1,156 m above sea level), Shandong Province, one of the "middle-low mountains" of eastern China. The relics have been observed to posses the systematic features of glacial erosion, trough and valley striations, and moraine deposits. The applied dating method shave confirmed that there were not only glacial relics of the last Ice Age(Wurm), but also Holocene glacial relics in the Mengshan Mountain area. Therefore, in order to further establish the corresponding relationship between the glacier, loess, stream sediment series, and MIS in the Mengshan Mountain area, a large number of chronological studies have been carried out regarding the various types of sediments in the area, and 24 dating datahave been obtained using OSL, CRN, and 14 Cmethods.On this basis, the corresponding relationship between the sedimentary sequences and the MIS was established for the first time in eastern China, which in dicates the environmental changes which had occurred in eastern China since 80 ka. These discoveries s and chronological study results confirm the existence of the Last Ice Age, as well as Holocene glacial relics at Mengshan Mountain, there by confirming that Quaternary glaciation had occurred in the middle-low mountain areas of eastern China. 展开更多
关键词 OSL CRN MIS glacial RELICS last Ice age HOLOCENE Eastern China
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The Glacial(MIS 3-2)Outlet Glacier of the Marsyandi Nadi-icestream-network with its Ngadi Khola Tributary Glacier(Manaslu-and Lamjung Himalaya):The Reconstructed Lowering of the Marsyandi Nadi Ice Stream Tongue down in to the Southern Himalaya Foreland 被引量:2
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作者 Matthias KUHLE 《Journal of Mountain Science》 SCIE CSCD 2014年第1期236-287,共52页
For the reconstruction of past climate variations,investigations on the history of glaciers are necessary.In the Himalaya,investigations like these have a rather short tradition in comparison with other mountains on e... For the reconstruction of past climate variations,investigations on the history of glaciers are necessary.In the Himalaya,investigations like these have a rather short tradition in comparison with other mountains on earth.At the same time,this area on the southern margin of Tibet is of special interest because of the question as to the monsoon-influence that is connected with the climate-development.Anyhow,the climate of High Asia is of global importance.Here for the further and regionally intensifying answer to this question,a glacial glacier reconstruction is submitted from the CentralHimalaya,more exactly from the Manaslu-massif.Going on down-valley from the glacial-historical investigations of 1977 in the upper Marsyandi Khola(Nadi) and the partly already published results of field campaigns in the middle Marsyandi Khola and the Damodar- and Manaslu Himal in the years 1995,2000,2004 and 2007,new geomorphological and geological field- and laboratory data are introduced here from the Ngadi(Nadi) Khola and the lower Marsyandi Nadi from the inflow of the Ngadi(Nadi) Khola down to the southern mountain foreland.There has existed a connected ice-stream-network drained down to the south by a 2,100-2,200 m thick and 120 km long Marsyandi Nadi main valley glacier.At a height of the valley bottom of c.1,000 m a.s.l.the Ngadi Khola glacier joined the still c.1,300 m thick Marsyandi parent glacier from the Himalchuli-massif(Nadi(Ngadi) Chuli) – the south spur of the Manaslu Himal.From here the united glacier tongue flowed down about a further 44 km to the south up to c.400 m a.s.l.(27°57'38 "N/84°24'56" E) into the Himalaya fore-chains and thus reached one of or the lowest past ice margin position of the Himalayas.The glacial(LGP(Last glacial period),LGM(Last glacial maximum) Würm,Stage 0,MIS 3-2) climatic snowline(ELA = equilibrium line altitude) has run at 3,900 to 4,000 m a.s.l.and thus c.1,500 altitude meters below the current ELA(Stage XII) at 5,400-5,500 m a.s.l.The reconstructed,maximum lowering of the climatic snowline(ΔELA = depression of the equilibrium line altitude) about 1,500 m corresponds at a gradient of 0.6°C per 100 altitude meters to a High Glacial decrease in temperature of 9°C(0.6 × 15 = 9).At that time the Tibetan inland ice has caused a stable cold high,so that no summer monsoon can have existed there.Accordingly,during the LGP the precipitation was reduced,so that the cooling must have come to more than only 9°C. 展开更多
关键词 Ice age GLACIATION HIMALAYA Manaslu Ngadi Khola Icestream network Last glacial period
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Glacial-Interglacial Atmospheric CO_2 Change——The Glacial Burial Hypothesis 被引量:2
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作者 Ning ZENG Department of Meteorology and Earth System Science Interdisciplinary Center, University of Maryland, USA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第5期677-693,共17页
Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation,... Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation, the advancement of continental ice sheets buries vegetation and soil carbon accumulated during warmer periods. At deglaciation, this burial carbon is released back into the atmosphere. In a simulation over two glacial-interglacial cycles using a synchronously coupled atmosphere-land-ocean carbon model forced by reconstructed climate change, it is found that there is a 547-Gt terrestrial carbon release from glacial maximum to interglacial, resulting in a 60-Gt (about 30-ppmv) increase in the atmospheric CO<SUB>2</SUB>, with the remainder absorbed by the ocean in a scenario in which ocean acts as a passive buffer. This is in contrast to previous estimates of a land uptake at deglaciation. This carbon source originates from glacial burial, continental shelf, and other land areas in response to changes in ice cover, sea level, and climate. The input of light isotope enriched terrestrial carbon causes atmospheric &#948;<SUP>13</SUP>C to drop by about 0.3‰ at deglaciation, followed by a rapid rise towards a high interglacial value in response to oceanic warming and regrowth on land. Together with other ocean based mechanisms such as change in ocean temperature, the glacial burial hypothesis may offer a full explanation of the observed 80–100-ppmv atmospheric CO<SUB>2</SUB> change. 展开更多
关键词 atmospheric CO2 ice age glacial burial hypothesis CLIMATE
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Optically stimulated luminescence dating of young glacial sediments from the eastern Qinghai-Tibetan Plateau 被引量:8
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作者 ZENG Lan-hua OU Xian-jiao +1 位作者 LAI Zhong-ping ZHOU Shang-zhe 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1174-1185,共12页
Poor bleaching is a significant problem for Optically Stimulated Luminescence(OSL) dating of glacial sediments. Five young glacial samples(including two modern analogues) from different depositional settings were coll... Poor bleaching is a significant problem for Optically Stimulated Luminescence(OSL) dating of glacial sediments. Five young glacial samples(including two modern analogues) from different depositional settings were collected beyond the Yingpu Glacier in the eastern Qinghai-Tibetan Plateau. De was determined using different OSL methods. The luminescence characteristics and dating results showed that the large aliquot quartz Blue Stimulated Luminescence(BSL) is more applicable than polymineral infrared stimulated luminescence(IRSL) method. Small aliquot quartz BSL results showed poor luminescence properties due to low luminescence sensitivity of quartz in this area. The dating results also indicated that glaciofluvial samples deposited close to ice margin(~40 m and ~700 m) and supraglacial debris dominated lateral moraine samples are relatively well-bleached, whereas samples from ground moraine and low terminal moraine were poorly bleached, probably due to containing subglacial and englacial debris. The residual doses of glaciofluvial and lateral moraine crest samples were below a few Gy and age overestimations were below a few hundred years. The ground moraine and low terminal moraine samples had residual doses as high as ~110 Gy, and ages were overestimated by ~15-17 ka. 展开更多
关键词 glacial sediments Optically stimulated luminescence Quartz Residual age Qinghai-Tibetan Plateau
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Glacier variations and rising temperature in the Mt.Kenya since the Last Glacial Maximum 被引量:1
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作者 CHEN An-an WANG Ning-lian +2 位作者 GUO Zhong-ming WU Yu-wei WU Hong-bo 《Journal of Mountain Science》 SCIE CSCD 2018年第6期1268-1282,共15页
High-resolution imagery can be used to reconstruct former glacier boundaries through the identification of glacial erosional and sedimentary geomorphology. We employed moraine mapping and the accumulation–area ratio ... High-resolution imagery can be used to reconstruct former glacier boundaries through the identification of glacial erosional and sedimentary geomorphology. We employed moraine mapping and the accumulation–area ratio method(AAR), in conjunction with Landsat, Google Earth, and SRTM imagery, to reconstruct glacier boundaries and equilibrium-line altitudes(ELAs) for Mt. Kenya in the Last Glacial Maximum(LGM), the Little Ice Age(LIA), and at present. Our results show that the areas of Lewis Glacier and the Tyndall-I glacier system were 0.678 km^2 and 0.390 km^2, respectively, during the maximum of LIA. Those mean that the both glaciers have shrunken by 87.0% and 88.7%, respectively since the LIA. Area change ratios for each glacier were significantly larger in the period of 2000 through 2015 than the former periods, indicating that glacier recession has accelerated. Continuous ice loss in this region has been driven by rising temperature and fluctuating precipitation. Linear regression data for Lewis glacier show that mass balance sensitivity to dry season temperature was –315 mm w.e./℃, whereas the sensitivity to dry season precipitation was 5.2 mm w.e./mm. Our data also show that the ELA on the western slope of Mt. Kenya rose by 716-816 m from the LGM to the modern era, corresponding to that temperature rose by 5.2℃-6.5℃. 展开更多
关键词 Remote sensing Last glacial Maximum Little Ice age Glacier area Equilibrium-linealtitudes Mt. Kenya
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SEA SURFACE SALINITY AND BOTTOM WATER OXYGENATED CONDITIONS IN WESTERN EQUATORIAL PACIFIC MARGINAL SEAS DURING THE LAST GLACLAL AGE
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作者 李铁钢 秦蕴珊 +1 位作者 董太禄 苍树溪 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第1期1-6,共6页
Based on Core GGC-6 from the South China Sea (SCS) and Core GGC-29 from the Sulu Sea,planktonic and benthic foraminifera and organic carbon measurements were used to evaluate the Water mass conditions in these sea are... Based on Core GGC-6 from the South China Sea (SCS) and Core GGC-29 from the Sulu Sea,planktonic and benthic foraminifera and organic carbon measurements were used to evaluate the Water mass conditions in these sea areas during the last glacial age. The results show that the higher organic carbon contents in the SCS and Sulu Sea during the last glacial period were mainly caused by low dissolved oxygen concentrations in bottom waters and that in the last glacial to Holocene, the fluctuation of dissolvd oxygen in the bottom weters was large in the SCS and reatively stable in the Sulu Sea. In addition, increased precipitation reduced surface water salinities, which at the water column to be more stratified in the SCS and Sulu Sea during the last glacial period. This process lowered dissolved oxygen concentrations in bottom waters, which resulted in better preservation of organic matter in both basins. 展开更多
关键词 SALINITY oxygenated condition LAST glacial age SOUTH China SEA SULU SEA
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The past,present,and future of the Siberian Grouse(Falcipennis falcipennis)under glacial oscillations and global warming
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作者 Wendong Xie Kai Song +2 位作者 Siegfried Klaus Jon E.Swenson Yue-Hua Sun 《Avian Research》 SCIE CSCD 2022年第1期57-63,共7页
Global climate change has a significant effect on species,as environment conditions change,causing many species'distributions to shift.During the last three million years,the earth has experienced glacial oscillat... Global climate change has a significant effect on species,as environment conditions change,causing many species'distributions to shift.During the last three million years,the earth has experienced glacial oscillations,forcing some species to survive in ice-free refugia during glacial periods and then disperse postglacially.In this study,by assessing the potential distribution of Siberian Grouse(Falcipennis falcipennis),we used Global Circular Models and Representative Concentration Pathways to model their pattern of range changes during glacial oscillations and the potential impact of present global warming.We used 158 location records of Siberian Grouse to generate a full climate model using 19 bioclimate variables in MaxEnt.We discarded variables with a correlation coefficient larger than 0.8 and relatively lower modeling contributions between each pair of correlated variables.Using the remaining variables,we created a normally uncorrelated simple climate model to predict the possible distribution of Siberian Grouse from the most recent Ice Age to present and to 2070.Then we added geographical data and the human interference index to construct a multiple factor full model to evaluate which were important in explaining the distribution of Siberian Grouse.The Total Suitability Zone(P≥0.33)of Siberian Grouse is about 243,000km^(2) and the Maximum Suitability Zone(P≥0.66)is 36,000km^(2) and is confined to the Russian Far East.Potential habitat modeling suggested that annual precipitation,annual mean temperature,and the distance from lakes are the most explanatory variables for the current distribution of Siberian Grouse.The distribution center moved to the southeast during the Last Glacial Maximum and spread back to the northwest after the ice melted and temperatures rose.The total area range of Siberian Grouse experienced a dramatic loss during the Last Glacial Maximum.Global warming is presently forcing the Siberian Grouse to migrate northward with a contraction of its range.There is an urgent need to protect its habitat,because little of its Maximum Sustainable Zone is protected,although there are some large reserves in that area. 展开更多
关键词 Climate change Falcipennis falcipennis Ice age refugia Last glacial maximum
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末次冰期以来日本海陆源沉积的地球化学记录及其对海平面和气候变化的响应 被引量:13
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作者 邹建军 石学法 +1 位作者 刘焱光 刘季花 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2010年第2期75-86,共12页
通过对日本海Ulleung盆地KCES-1岩心中的主微量元素、稀土元素及粒度的综合分析,探讨了沉积物来源及其控制因素。结合地层年代模型,恢复了研究区48ka以来的古环境记录。结果显示,日本海Ulleung盆地沉积物以陆源碎屑为主,沉积物中主微量... 通过对日本海Ulleung盆地KCES-1岩心中的主微量元素、稀土元素及粒度的综合分析,探讨了沉积物来源及其控制因素。结合地层年代模型,恢复了研究区48ka以来的古环境记录。结果显示,日本海Ulleung盆地沉积物以陆源碎屑为主,沉积物中主微量元素(Al、K、Fe、Mg、Na、Ti、Th、Sc、Rb、Sr、Cr、Co、Hf、Zr)含量普遍低于平均页岩。稀土元素丰度(ΣREE)为80~213μg/g,与长江、黄河及中国黄土接近,高于日本上地壳。球粒陨石标准化显示,沉积物中轻稀土显著富集,有显著的Eu负异常(0.6~0.8),Ce异常不显著。元素比值(La/Th、Th/Sc)及La/Th-Hf物源性质判别分析显示,研究区沉积物主要来源于上地壳,母岩落入长英质源岩区。在11~18ka,主微量元素的分布特征与11~0ka及48~18ka有显著差异。海平面和全球气候变化是控制主微量元素时空分布的重要因素。化学蚀变指数CIA(45~61)显示沉积物源区化学风化程度较弱,18ka以前风化程度低于18ka以后风化程度,暗示气候由干冷向暖湿转移。这与全球气候变化和东亚夏季风强度变化趋势一致。 展开更多
关键词 主微量元素 稀土元素 末次冰期 古气候 日本海
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“小冰河期”促成了温病学说 被引量:6
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作者 杨葛亮 杨学 《河南中医》 2009年第4期325-326,共2页
明清"小冰河时期"气候剧变,天灾不断,朝代更迭,战端纷纭,大疫流行,为温病学的形成提供了必要的客观条件。经历了两千多年缓慢摸索的温病学被时势迅猛地推上了历史舞台,成功地摆脱了伤寒学的"束缚",形成了独成一派... 明清"小冰河时期"气候剧变,天灾不断,朝代更迭,战端纷纭,大疫流行,为温病学的形成提供了必要的客观条件。经历了两千多年缓慢摸索的温病学被时势迅猛地推上了历史舞台,成功地摆脱了伤寒学的"束缚",形成了独成一派的理论体系。 展开更多
关键词 “小冰河时期” 伤寒学 温病学
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Ice-wedge Pseudomorphs Showing Climatic Change Since the Late Pleistocene in the Source Area of the Yellow River, Northeast Tibet 被引量:3
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作者 CHENG Jie ZHANG Xujiao +4 位作者 TIAN Mingzhong YU Wenyang YU Jiangkuan TANG Dexiang YUE Jianwei 《Journal of Mountain Science》 SCIE CSCD 2005年第3期193-201,共9页
The source area of the Yellow River is located in the northeastern Tibetan Plateau, and is a high-elevation region with the annual mean temperature of -3.9℃. The ice-wedge pseudomorphs discovered in this region are r... The source area of the Yellow River is located in the northeastern Tibetan Plateau, and is a high-elevation region with the annual mean temperature of -3.9℃. The ice-wedge pseudomorphs discovered in this region are recognized as two types. One was found in sandy gravel beds of the second terrace of the Yellow River. This ice-wedge pseudomorph is characterized by higher ratio of breadth/depth, and are 1-1.4 m wide and about 1 m deep. The bottom border of the ice-wedge pseudomorph is round arc in section. Another discovered in the pedestal of the second terrace has lower ratio of width/depth, and is o.3-1.0 m wide and 1-2 m deep. Its bottom border is sharp. Based on the TL dating, the former was formed at the middleHolocene (5.69±0.43 ka BP and 5.43±0.41 ka BP), that is, the Megathermal, and the latter was formed at the late Last Glacial Maximum (13.49±1.43 ka BP). Additionally, the thawing-freezing folders discovered in the late Late Pleistocene proluvium are 39.83±3.84 ka BP in age. The study on the ice-wedge pseudomorphs showed that the air temperature was lowered by up to 6-7℃ in the source area of the Yellow River when the ice-wedge pseudomorphs and thawing-freezing folds developed. 展开更多
关键词 Ice-wedge pseudomorph PALEOCLIMATE Last glacial age MEGATHERMAL the source area of the Yellow River Tibetan Plateau
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