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Grain-size Characteristics and Climate Variability in TMS5e Sequence of Tumen Section in Southern Tengger Desert,Northwestern China

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Chinese Geographical Science 2012年第1期22卷 48-62页

作者： WEN Xiaohao LI Baosheng WANG Fengnian ZHENG Yanming NIU Dongfeng SI Yuejin ou xianjiao School of Geographical Science South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 China School of Geography and Planning Sun Yat-Sen University Guangzhou 510275 China School of Geography and Tourism Jiaying University Meizhou 514015 China

The TMS5e sequence from the Tumen section, at the southern edge of Tengger Desert in the northwestern China, is synchronous with Marine Isotope Stage 5e （MIS5e）. It consists of 16 layers of aeolian dune sands, 11 layers of lacustrine loess-like facies, and 5 layers of lacustrine facies. The results of grain-size analysis shows that the pa- laeo-mobile dune sands, palaeo-fixed to semi-fixed dune sands and loess-like sandy loams are mainly composed of sands, ranging from 70% to 96%; their silt contents ranged from 4% to 20%, and their clay contents ranged from 1% to 5%; the climate under which the aeolian dune sands were deposited is similar to that under which modern mobile dune sands form, which is caused by the dominance of the cold, dry East Asian winter monsoon. In contrast, the lacustrine loess-like facies and lacustrine facies had a lower sand contents than those of the three aeolian dune sands, but have higher silt and clay contents, most of their sand content ranged from 30% to 60%, their silt contents ranged from 35% to 55%, and their clay contents ranged from 6% to 20%. The lacustrine loess-like facies and lacustrine facies formed under the influence of the warm, humid East Asian summer monsoon based on their similarity with modern sediments. The grain-size indicator Mz （mean grain diameter） and the SC/D value in the TMS5e sequence indicate climatic insta- bility at the southern edge of the Tengger Desert during MIS5e, with at least 14 fluctuations between a warm, humid climate and a cold, dry climate, divided into five stages： TMS5e5 （139 kyr to 129.3 kyr B.P.）, TMS5e4 （129.3 kyr to 124 kyr B.P.）, TMS5e3 （124 kyr to 119.5 kyr B.P.）, TMS5e2 （119.5 kyr to 116.5 kyr B.P.）, and TMS5el （116.5 kyr to 113.7 kyr B.P.）. These correspond roughly to MIS5e5, MIS5e4, MIS5e3, MIS5e2, and MIS5el, respectively, in the GRIP ice core data.

关键词： Tengger Desert Tureen section TMS5e sequence grain-size characteristics palaeoclimate reconstruction Marine Isotope Stage 5e (MIS5e)

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Phases of Environmental Evolution Indicated by Primary Chemical Elements and Paleontological Records in the Upper Pleistocene-Holocene Series for the Salawusu River Valley,China

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 555-565页

作者： LI Baosheng WEN Xiaohao QIU Shifan David Dian ZHANG DU Shuhuan CHEN Deniu ou xianjiao NIU Dongfeng School of Geography South China Normal University Guangzhou Guangdong 510631 State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇an Shaanxi 710061 Department of Geography and Geology the University ofHong Kong Hong Kong Institute of Zoology Chinese Academy of Sciences Beijing 100080

Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section in China＇s Salawnsu River valley into six segments： MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6. The boundary ages for MGS1 （the Dishaogouwan and Dagouwan Formations）, MGS2 （the upper Chengchuan Formation）, MGS3 （the middle Chengchuan Formation）, MGS4 （the lower Chengchuan Formation）, MGS5 （most strata of the Salawusu Formation） and MGS6 （the bottom of the Salawusu Formation and the top of the Lishi Formation） correspond to those of MIS1, MIS2, MIS3, MIS4, MISS and MIS6, respectively, from deep sea sediments or continental glaciers. MGS5 can be subdivided into five subsegments （MGS5a, MGS5b, MGS5c, MGS5d and MGS5e） and the boundary ages of these subsegments correspond to those of MISSa, MISSb, MIS5c, MIS5d and MIS5e, respectively. Based on the paleoenvironment and paleoecology indicated by the primary chemical elements, fossil vertebrates, mollusks and pollen grains, we hypothesize that MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6 and the subsegments of MGS5 match the corresponding stages for oxygen isotopes in the deep sea sediments and continental glaciers, and the substages of MIS5 in terms of climatic characters, further explaining the phenomena that determined the formation of the late Quaternary strata and the paleontology of the Salawusu River valley. These phenomena relate to fluctuations in the global climate （and particularly in the East Asian monsoon） during the glacial and interglacial periods.

关键词： Salawusu River valley Upper Pleistocene-Holocene Series primary chemical elements,phases of evolution paleontological records

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Evidence for glaciation predating MIS-6 in the eastern Nyainqêntanglha Range, southeastern Tibet

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Science China Earth Sciences 2021年第4期64卷 559-570页

作者： Shangzhe ZHou Jinming XIE xianjiao ou Liubing XU Yong SUN Xuezhen ZENG Xiaoxia WEN Renrong CHEN Hong YANG Xianmei HUANG Yazhong ZHou Jinjin SUN Department of Geography Science South China Normal UniversityGuangzhou 510631China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China School of Geography and Tourism Jiaying UniversityMeizhou 514015China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Southeastern Tibet is one of the most glaciated regions on the Tibetan Plateau both at present and during the Quaternary. Numerical dating of glacial deposits has allowed the establishment of a provisional chronology of Quaternary glacial fluctuations in this region, with the oldest glaciation(Guxiang Glaciation) occurring in marine oxygen isotope stage 6(MIS-6).During our recent field investigations, a morphostratigraphically older lateral moraine than that of the Guxiang Glaciation has been first identified, which is ~500–600 m above the Guxiang Glaciation moraine and discontinuously preserved on valley shoulders in the Bodui Zangbo River valley, eastern Nyainqêntanglha Range in southeastern Tibet. Considering the moraine is best preserved at Nitong Village, here we name the glacier advance which deposited the moraine as "Nitong Glaciation". Using electron spin resonance(ESR) technique, we dated the Nitong Glaciation moraine to 506.3±60.4 ka. Taking into account the age error and climatic conditions, we consider it most likely that the Nitong Glaciation occurred during MIS-12, although it might had happened sometime earlier.

关键词： Southeastern Tibet MIS-12 Glaciation ESR dating Quaternary Glaciation

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Paleoclimate change recorded in the red earth and brown-yellow sediment of Late Quaternary for northeastern part of Guangdong Province,south to the Nanling Mountains,China

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Chinese Science Bulletin 2008年第24期53卷 3866-3875页

作者： LI BaoSheng WEN XiaoHaoi DAVID DianZhang QIU ShiFan DONG YOXiang LI ZhiWen DU ShuHuan ou xianjiao LI HouXin NIU DongFeng YANG Yi School of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Institute of Earth Environment Chinese Academy of Sciences Xi'an 710061 China Department of Geography University of Hongkong Hongkong China School of Geography and Planning Sun Yat-Sen University Guangzhou 510275 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The paleoenvironment indicated by the geochronology,major oxides——SiO2,Al2O3 and TOFE(Fe2O3 + FeO),and CIA(Chemical Index of Alteration) value of the red earth and brown-yellow silt primarily characterized by the Linjiang stratigraphic section,based on the geological investigation of Late Quaternary along the river banks of northeastern part of China's Guangdong Province,south to the Nanling Mountains,allow us to hypothesize that the red earth on the first terrace in northeastern part of Guangdong belongs to reticulated red clay developed in a hot-wet environment of the last interglacial period(132―73 ka BP),similar to the monsoon environment in the northern margin of modern tropical zone,while the overlying brown-yellow silt layer mainly accumulated in a monsoon environment of warm temperate zone in the last glacial period(73―11 ka BP),with the aeolian sand LJ3 representing an extreme period of worsening *** a hypothesis corresponds well with predecessors' research on the paleoenvironment indicated by abundant fossils in both south and east to the Nanling ***,it follows that the bioclimatic zone did experience a large and rapid vicissitude in northeastern part of China's Guangdong Province,and even in the full extent of the region south to the Nanling Mountains from the last interglacial period to the last glacial period,with the red earth being replaced by the brown-yellow silty sediment,and even maybe with the Ailuropoda-Stegodon Fauna being replaced by the Penghu *** study may provide an important geological demonstration for the environmental response to global change in China's low latitudes on a 10 ka scale.

关键词：中国广东东北部第四纪新生代网状红色粘土褐黄色沉积物

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Cold events of Holocene indicated by primary elements distribution of the high-resolution sand dunes in the Salawusu River Valley

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Journal of Geographical Sciences 2008年第1期18卷 26-36页

作者： NIU Dongfeng LI Baosheng DU Shuhuan WEN Xiaohao QIU Shifan ou xianjiao YANG Yi School of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quatemary Geology Institute of Earth Environment CAS Xi＇an 710061China Baotou Vocational ＆ Technical College Baotou 010022 China

The components of the primary elements in the dune sands for the MGS1 subsection of the Milanggouwan section in the Salawusu River valley, compared with those of modern dune sands, show that they were caused by East Asian winter monsoon in the Mu Us desert during Holocene. The examined ages for the 11 layers of dune sands, based on the average sedimentary rate, are： 0 to 960, 1350-2240, 2470 to 3530, 4000 to 4180, 4290 to 4350, 4380 to 4760, 5040 to 5920, 6570 to 8270, 9020 to 9700, 9880 to 10160 and 10580 to 11080 a BP, respectively. The climatic events indicated by these dune sands are consistent with those records in the Huguangyan volcanic lake, Zoige peat bog, Hulu cave and Dunde ice core, particularly with the climatic fluctuations of the North Atlantic since 11 000 a BP. Among them, patterns from B0 to B8 correspond to the peak values of 0MD, 2D, 4D, 6D＋8D＋10D, 12D, 14D, 16D, 18D and 20D respectively. It might be caused by the North Atlantic ice age induced by the heat circulation, which strengthened the polar high pressure and Siberian-Mongolian high pressure and further led to the dominance of the winter monsoon over China＇s desert area.

关键词： Salawusu River Valley Holocene dune sands primary elements cold events

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Deposition of sandstorms in a vegetation-covered sand dune in Ejin Oasis and its characteristics

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Journal of Geographical Sciences 2006年第4期16卷 502-508页

作者： WENXiaohao LI Baosheng WANG Wei LI Sen ou xianjiao ZHENG Yanming Sehool of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment CAS Xi＇an 710075 China Department of Tourism Resourees and Environment Foshan University Foshan 528000 China

＂Ejin Section＂ found in a typical vegetation-covered sand dune in Ejin Oasis was investigated. In this study, 263 samples were taken from the section for grain-size analysis, 25 for chemical analysis, 11 for ^14C dating and 6 for scanning electron microscope （SEM）. The results of the study indicate that 3 types of the sediments in the section can be identified, YS, LS and ST. YS, homogeneous yellow-brown dune sands, is equal to those of inland deserts, LS, loess-like sandy soils, is the same as the sandy loess in the middle Yellow River and modem falling dusts, and ST, sandy sediments interbeded with the deadwood and defoliation of Tamarix spp, represents the depositional process of the section interrupted by abrupt changes in climate. The Ejin Section has recorded the repeated dust-storms or sandstorms since 2500 yr BP and the peak periods of the dust-storms or sandstorms revealed by the section are consistent with the records of ＂dust rains＂ in historical literatures, indicating that the change of climate is a key factor to increase sandstorms or dust-storms, whereas, ＂artificial＂ factor may only be an accelerating one for desertification.

关键词： Ejin Oasis vegetation-covered sand dune dust storm sandstorm grain size major chemical element

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光释光测年基本流程

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地理科学进展 2013年第5期32卷 683-693页

作者：赖忠平欧先交中国科学院青海盐湖研究所释光测年实验室西宁810008 嘉应学院地理科学与旅游学院梅州514015

光释光测年是对沉积物上一次曝光事件年代的测定。自20世纪80年代该方法提出以来，得到了越来越广泛的应用。相对于”C测年，光释光测年虽存在误差偏大的不足（一般5％～10％），但是具有以下明显优势：①其测年年限范围比前者大得多；... 详细信息

光释光测年是对沉积物上一次曝光事件年代的测定。自20世纪80年代该方法提出以来，得到了越来越广泛的应用。相对于”C测年，光释光测年虽存在误差偏大的不足（一般5％～10％），但是具有以下明显优势：①其测年年限范围比前者大得多；②测年物质（石英或长石）丰富，这在干旱半干旱区的沙漠和湖泊中尤其重要，因为在这些地区很难找到可用于“C测年的有机质；③是对沉积物的直接定年；④测年事件包括曝光、受热（400℃以上）、火山、地震和晶体（方解石等）形成等。本文介绍了光释光测年的整个实验过程，包括采样、前处理、等效剂量测定、年剂量测定等，以期让有需要的地学同行了解这一方法，尤其是了解从地层或岩芯等取样的过程中应注意的事项。重点介绍单片再生剂量法（SAR）与标准生长曲线法（SGC）相结合测定等效剂量的实验方法（我们命名为***法）。该方法能大大提高仪器的使用效率，可节省仪器时间60％以上。通过氟硅酸溶蚀长石来提取石英的中颗粒（38—63gm）的前处理过程简便易行，获得的石英纯度高，且可以避免使用危险的氢氟酸。中国科学院青海盐湖研究所释光测年实验室近几年应用SAP,．SGC法对黄土、沙漠、湖泊、海洋、冰川、考古点等各种类型沉积物进行光释光测年，都获得了很好的结果。

关键词：光释光测年技术采样与实验室流程石英中颗粒法等效剂量测定的SAR SGC法

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Sedimentary characteristics of paleo-aeolian dune sands of Salawusu Formation in the Salawusu River Valley

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Journal of Geographical Sciences 2008年第2期18卷 211-224页

作者： ou xianjiao LI Baosheng JIN Heling DONG Guangrong David Dian ZHANG WU Zheng WEN Xiaohao ZENG Lanhua ouYANG Chuntao YANG Yi LIU Yufei School of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment CAS Xi＇an 710061 China Department of Geography Jiaying University Meizhou 514015 China Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China Department of Geography and Geology the University of Hong Kong Hong Kong China

The Salawusu Formation of Milanggouwan section in Salawusu River Valley includes 7 layers of paleo-mobile dune sands, and 4 layers of paleo-fixed and semi-fixed dune sands. Their structures have been observed and their grain size, surface textural features and several main chemical elements have been analyzed. The results showed that： 1） Some of the aeolian structural characteristics of these dune sands are similar to that of the recent dune sands. 2） They are also similar to the recent dune sands in grain size components, and parameters of Mz,σ, Sk and Kg, as well as in several main chemical components. 3） The scattergrams of Mz-σ and SiO2-Al2O3＋TOFE and the probability curves of grain size showed that these paleo-dune sands are different from paleosols and fluvio-lacustrine facies, but are consistency with recent dune sands. 4） Quartz sands have well roundness and surface textural features such as dish-shaped pits, crescent-shaped pits, pockmarked pits, upturned cleavage plates, siliceous precipitates and siliceous crevasses, indicating that they had been carried for a long time by the wind. As the 11 layers of paleo-dune sands possess the aeolian characteristics in structure, grain size, surface textural features and chemical elements, the origin of their formation should be attributed to eolation.

关键词： Salawusu River Valley Salawusu Formation paleo-aeolian dune sands aeolian sedimentary characteristics

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不同释光方法测试冰川沉积物等效剂量的尝试

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核技术 2013年第2期36卷 36-41页

作者：欧先交赖忠平曾兰华嘉应学院地理科学与旅游学院梅州514015 中国科学院寒区旱区环境与工程研究所冰冻圈科学国家重点实验室兰州730000

在青藏高原东部硬普沟采集6个冰川沉积光释光测年样品(2个现代样、3个新冰期和1个末次冰期样品),运用SAR结合SGC技术,采用石英大测片、小测片BSL以及多矿物IRSL等3种方法进行了等效剂量(De)的测试,SAR和SGC技术测得的De值相近。3种方法... 详细信息

在青藏高原东部硬普沟采集6个冰川沉积光释光测年样品(2个现代样、3个新冰期和1个末次冰期样品),运用SAR结合SGC技术,采用石英大测片、小测片BSL以及多矿物IRSL等3种方法进行了等效剂量(De)的测试,SAR和SGC技术测得的De值相近。3种方法的测试结果表明,De值IRSL>大测片BSL>小测片BSL。多矿物IRSL测得的De值比石英BSL偏高,表明长石比石英较难晒退,不适于该地冰川沉积测年。石英大测片适于晒退较好的样品。该地石英的释光敏感性较低,小测片的测试情况不理想,且不能完全区分不同晒退程度的颗粒。对于年代较老的、较明亮的冰川沉积样品,石英小测片甚至单颗粒技术可能是可行的。今后需要更多研究如何应对释光敏感性低的样品的测试问题。

关键词：光释光等效剂量单片再生剂量法标准生长曲线法小测片冰川沉积物

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天山乌鲁木齐河源末次冰期冰川沉积光释光测年

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冰川冻土 2019年第4期41卷 761-769页

作者：曾兰华欧先交陈嵘赖忠平嘉应学院地理科学与旅游学院广东梅州514015 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室江苏南京210008 汕头大学海洋科学研究院广东汕头515063 Department of Geography and Earth Sciences Aberystwyth UniversityCeredigion SY233DBUK

乌鲁木齐河源地区是中国冰川遗迹保存最丰富、地貌最典型的区域之一,是根据冰川遗迹重建第四纪冰川历史的理想地区。大量的研究工作以及技术测年结果也使其成为试验冰川沉积光释光(optically stimulated luminescence,OSL)测年可行性的... 详细信息

乌鲁木齐河源地区是中国冰川遗迹保存最丰富、地貌最典型的区域之一,是根据冰川遗迹重建第四纪冰川历史的理想地区。大量的研究工作以及技术测年结果也使其成为试验冰川沉积光释光(optically stimulated luminescence,OSL)测年可行性的理想地点。共采集了6个冰碛及上覆黄土样品用于光释光测年。提取38~63μm的石英颗粒,运用SAR-SGC法测试等效剂量。各种检验表明测试程序是适用的。通过地貌地层关系、重复样品、已有年代的对比等方法,检验该地冰川沉积OSL测年的可行性。结果表明,OSL年代结果与地貌地层新老关系非常吻合,与已有的其他测年技术的年代结果也具可比性,表明这些样品的OSL信号在沉积之前晒退较好,OSL年代是可信的。冰川观测站侧碛垄的OSL年代为14.8±1.2ka;9号冰川支谷口附近冰碛的OSL年代为13.5±1.1ka和17.2±1.3ka;上望峰冰碛的OSL年代为20.1±1.6ka。综合OSL年代结果与此前其他测年结果,这几套冰碛垄形成于深海氧同位素MIS2阶段应该是比较统一的认识。上望峰冰碛上覆黄土的OSL年代(10.5±0.8ka)也印证了该结论。OSL年代指示上望峰冰碛对应于末次冰期最盛期,冰川观测站和9号冰川支谷谷口冰碛对应于晚冰期。下望峰冰碛的OSL年代为36.3±2.8ka,对应于MIS3阶段。下望峰冰碛的形成时代,仍有待更多沉积学以及测年工作进一步确定。

关键词：冰川沉积光释光测年望峰冰碛末次冰期晒退天山乌鲁木齐河源

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