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Late Cenozoic uplift of the Liupan Mountains:Evidence from the Neogene loess deposits

Science China Earth Sciences 2024年第5期67卷 1480-1488页

作者： Zhilin HE Yansong QIAO Zhengtang GUO Chaoqin CHEN Long CHEN Yang FU Ye YANG Yanxia LIANG Xinru LIN guoqiao xiao Tao ZHAN Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China Institute of Ecological Geology Survey and Research of Heilongjiang Province Harbin 150030China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China School of Earth Sciences China University of GeosciencesWuhan 430074China Natural Resources Survey Institute of Heilongjiang Province Harbin 150036China

The Liupan Mountains,one of the important mountain ranges in western China,are located on the boundary between the northeastern Tibetan Plateau and the Ordos Block.The uplift history of the Liupan Mountains remains controversial.Loess deposits are good tracers of regional tectonic and geomorphic changes,because loess is sensitive to erosion and the formation and preservation of loess requires relatively flat highlands and relatively stable tectonic environments.We investigated the distribution of Neogene loess deposits on the western piedmont of the Liupan Mountains and examined a near-continuous loess section(Nanping section)on the piedmont alluvial highlands.Correlation of magnetic susceptibility stratigraphy with the QA-ⅠMiocene loess sequence dates this 56-m section covering the interval from~8.1 to 6.2 Ma.The lower boundary age of this section,together with previously reported Zhuanglang red clay(sand-gravel layers with intercalated loess during~9–8 Ma and near-continuous loess during~8–4.8 Ma)and Chaona red clay(~8.1–2.58 Ma),indicates that the Liupan Mountains were uplifted in the late Miocene(~9–8 Ma)and basically formed by~8 Ma,attesting to no intense mountain building since that time.In addition,based on the information from the Zhuanglang core and the QA-Ⅰsection,we infer that sizable parts of the Liupan Mountains were uplifted during the late Oligocene–early Miocene and did not experience intense uplift during~22–9 Ma.

关键词： Liupan Mountains Mountain building Neogene Loess Chinese Loess Plateau Late Miocene Late Oligocene–early Miocene

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Detrital-Zircon Evidence for the Origin of the Late Quaternary Loess in Qingzhou,Shandong Province and Its Implications for the Evolution of the Yellow River

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Journal of Earth Science 2022年第1期33卷 205-214页

作者： Yanfei Shen Meiyan Liang Jianxun Wu Shuzhen Peng guoqiao xiao Hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China School of Tourism Resources and EnvironmentTaishan UniversityTai'an 271021China

The loess depositions in Shandong Province are important parts of loess records in eastern China,but their origin and genetic linkage between the Yellow River and the Chinese Loess Plateau are still unclear.This paper presents the detrital-zircon evidence for the origin and provenance evolution of the Qingzhou loess in Shandong Province.The results show that:(1) the Qingzhou loess was sourced from the sandy lands within the North China Plain that were fed by the silty materials from the Chinese Loess Plateau,the mountainous region in central Shandong Province,and the Yanshan and Taihang Mountains;(2) the Qingzhou loess was mainly sourced from the loess materials transported by the Yellow River,and the basal age of the Qingzhou loess indicates the timing of intensified aridification of the North China Plain and integration of the Yellow River was not later than 0.5 Ma;and(3) the provenance and grain-size of the Qingzhou loess underwent a significant transition at ~0.22 Ma,which was related to the expansion of the sandy land within the North China Plain.Our results indicate that the origin of the loess on the North China Plain are obviously different from the loess on the Chinese Loess Plateau,and the increase of grain-size and accumulation rate in the loess records on the North China Plain at ~0.22 Ma was due to the environmental deterioration of the eastern China.

关键词： North China Plain loess Pleistocene zircon detrital-zircon Yellow River

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中国黄土磁性地层研究进展与展望

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海洋地质与第四纪地质 2024年第2期44卷 1-15页

作者：陈天然肖国桥林欣如潘卿中国地质大学(武汉)地理与信息工程学院流域关键带演化湖北省重点实验室武汉430078 中国地质大学(武汉)地球科学学院生物地质与环境地质国家重点实验室武汉430078 中山大学大气科学学院行星环境与宜居性研究实验室珠海519000

中国黄土是最重要的第四纪陆相气候记录之一,磁极性地层是建立第四纪黄土年代框架的主要方法之一。本文总结了中国黄土所记录的布容/松山(Brunhes/Matuyama)、加拉米诺(Jaramillo)、奥尔都维(Olduvai)和松山/高斯(Matuyama/Gauss)等几... 详细信息

中国黄土是最重要的第四纪陆相气候记录之一,磁极性地层是建立第四纪黄土年代框架的主要方法之一。本文总结了中国黄土所记录的布容/松山(Brunhes/Matuyama)、加拉米诺(Jaramillo)、奥尔都维(Olduvai)和松山/高斯(Matuyama/Gauss)等几个作为主要定年依据的极性倒转界限的研究结果,并将黄土记录的这些界限位置与深海记录进行了对比。结果发现,不同黄土剖面所记录的各地磁极性倒转界限的位置并不一致,其差异可超过一个黄土-古土壤旋回,且不能用lock-in效应、气候和沉积速率差异、黄土地层划分差异来解释。这些地磁极性界限位置的差异指示极性界限附近的黄土可能经历了不同程度的重磁化。同时,这些差异也导致了不同研究者基于磁极性地层所建立的轨道尺度的黄土年代标尺与深海氧同位素记录的对比存在较大分歧。未来对黄土所记录的地磁场相对古强度(RPI)的研究可望为识别极性倒转界限的真实位置提供依据,并最终解决中国黄土与深海记录轨道尺度对比方案的分歧。

关键词：黄土第四纪磁性地层重磁化地磁场相对古强度

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Sedimentary and geochemical evidence of Eocene climate change in the Xining Basin, northeastern Tibetan Plateau

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Science China Earth Sciences 2018年第9期61卷 1292-1305页

作者： Abu Sadat Md SAYEM Zhengtang GUO Haibin WU Chunxia ZHANG Fan YANG guoqiao xiao Zhilin HE Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Department of Geological Sciences Jahangirnagar University Dhaka 1342 Bangladesh CAS Center for Excellence in Life and Paleoenvironment Bering 100044 China State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Wuhan 430074 China

The northeastern Tibetan Plateau began to grow during the Eocene and it is important to understand the climatic history of Asia during this period of so-called ‘doubthouse' conditions. However, despite major advances in the last few decades,the evolutionary history and possible mechanisms of Eocene climate change in the northeastern Tibetan Plateau remain unclear.The Xining Basin in the northeastern Tibetan Plateau contains a continuous sequence of Early to Late Eocene non-marine sediments which provides the opportunity to resolve long-term climate changes during this period. In this study, we report the results of analyses of lithofacies, sediment color and geochemistry of bulk samples collected from the Xijigou section of the Xining Basin. An abrupt lithofacies change between the Early(~52–40 Ma) and Late Eocene(~40–34 Ma) indicates a change in the depositional environment from a shallow lake to a playa lake in response to a significant climatic shift. During ~52–40 Ma,higher values of sediment redness(a*), redness/lightness(a*/L*) and higher modified Chemical Index of Weathering(CIW′)indicate a relatively warm and humid climate, while from ~40–34 Ma the lower values of a*, a*/L*and lower CIW′ imply subhumid to semi-arid climatic conditions. The paleoclimatic records indicate a long-term(~52–34 Ma) trend of decreasing chemical weathering, consistent with global climate change. An abrupt sharp excursion of the proxy records during ~42–40 Ma suggests a relatively brief warm interval, corresponding to the Middle Eocene Climatic Optimum(MECO). We suggest that global cooling substantially reduced humidity in inner Asia, resulting in sub-humid to semi-arid climatic conditions after 40 Ma in the Xining Basin, which may have been responsible for the long-term trend of decreasing chemical weathering during the Eocene.

关键词：气候变化晚始新世沉积高原西藏东北证据进化历史

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Magnetostratigraphy and provenance of the Qingzhou loess in Shandong province

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Journal of Arid Land 2011年第3期3卷 184-190页

作者： ShuZhen PENG LiJun ZHU guoqiao xiao YanSong QIAO ZhiDong GAO DongDong CHEN Department of Tourism Resources and Environment Taishan University Taian 271021 China College of Urban and Environment Sciences of Shanxi Normal University Linfen 041000 China Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China

Loess deposits with varying thickness are widely distributed on the intermontane valleys and piedmont zones on the northern side of the central Shandong mountainous regions. However, the basal ages and material resources of the loess deposits are not clear. The paper studied the Qingzhou loess profile in Shandong with magnetostratigraphic and optical stimulated luminescence （OSL） methods and further investigated its main provenances with the mineralogical methods. The magnetostratigraphic results showed that the Brunhes/Matuyama （B/M） reversal boundary was not recognized, suggesting a basal age younger than 0.78 Ma. Extrapolations by sedimentation rates, based on the upper part depositional rate from the OSL age, the basal age of the Qingzhou loess is about 0.5 Ma. Until now, older loess deposits have not been reported on the northern side of the central Shandong mountainous regions. The results of the paper indicate that the loess deposits in this area might have strated from the Middle Pleistocene. The basal age of Qingzhou loess is approximately synchronous with the Xiashu loess in the middle-lower reaches of Yangtze River. Major components of clay minerals in the Qingzhou profile are dominated by illite. Other clay mineral compositions are mainly smectite, chlorite and kaolinite, which are similar with the Xifeng loess in the Loess Plateau. However, the contents of smectite and the ratios of illite and kaolinte in the Qingzhou loess samples are higher than those in the Xifeng loess samples of the Loess Plateau, indicating that the loess in the northern side of the central Shandong mountainous regions has different sources from that of the loess deposits in the Loess Plateau. The clay mineral analysis further reinforces the earlier conclu- sion that the marine strata exposed in the Laizhou Bay and the fluvial plain of the lower reaches of Yellow River during the glacier periods are the main material sources for the Qingzhou loess deposits, which is an indicator to the local aridification of the lower reaches o

关键词： Loess magnetostratigraphy sedimentology material provenance Qingzhou

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黄河从未经由永定河入海

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海洋地质与第四纪地质 2024年第2期44卷 46-54页

作者：林欣如肖国桥杨吉龙潘卿赵卿宇梁美艳中国地质大学(武汉)地理与信息工程学院流域关键带演化湖北省重点实验室武汉430078 中国地质大学(武汉)地球科学学院生物地质与环境地质国家重点实验室武汉430078 中国地质调查局天津地质调查中心天津300170

黄河是中国第二长河,其形成和演化对中国地貌格局的演化和古气候变化具有重要的指示意义。19世纪以来,陆续有学者提出黄河在沿三门峡入海之前曾由河套盆地向东经由永定河入海的猜想,这一假想的河流可称为“北黄河”。这一猜想在地理学... 详细信息

黄河是中国第二长河,其形成和演化对中国地貌格局的演化和古气候变化具有重要的指示意义。19世纪以来,陆续有学者提出黄河在沿三门峡入海之前曾由河套盆地向东经由永定河入海的猜想,这一假想的河流可称为“北黄河”。这一猜想在地理学领域有较广泛的影响,然而,一直以来却鲜有证据明确证实或证伪这一猜想。本文综合新近发表的华北平原钻孔物源证据、汾渭盆地沉积和三门峡地区的地貌证据对这一猜想进行了探讨。这些证据表明,在约1.6 MaBP之前,位于永定河冲积扇及渤海湾沿岸的所有钻孔均未接收到来自黄河上游和中游的物质,表明此阶段三门峡和北黄河都未开通;而在约1.6 MaBP后,黄河上游和中游的物质开始进入渤海湾,但永定河冲积扇仍缺乏来自黄河上游和中游的物质。结合汾渭盆地三门组在约1.6 Ma快速结束并转变为黄土沉积的证据判断:黄河在约1.6 Ma以前尚未贯通,在约1.6 Ma以后经由三门峡进入华北平原东流入海,即黄河从未经由永定河入海。

关键词：黄河演化物源示踪永定河三门峡

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Siloles and Acetenyl Aromatics Copolymers: Synthesis, Characterization and Photophysical Properties

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中国化学:英文版 2015年第5期33卷 550-558页

作者： Zhenhua He guoqiao Lai Zhifang Li xiao Yuan Yongjia Shen Chengyun Wang Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and TechnologyShanghai 200237China Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhouZhejiang 310012China

Two copolymers,poly(1,1-dimethyl-3,4-diphenylsilole-alt-N-hexyl-3,6-diethynylcarbazole)(PS-DyCz)and poly-(1,1-dimethyl-3,4-diphenylsilole-alt-2,7-diethynyl-9,9'-dihexylfluorene)(PS-DyF),were synthesized by Sonogashira coupling reaction of 2,5-dibromo-1,1-dimethyl-3,4-diphenylsilole and N-hexyl-3,6-diethynylcarbazole or 2,7-diethynyl-9,9'-dihexylfluorene,respectively.The chemical structures of the copolymers were characterized by NMR,FT-IR techniques.Their thermal and photophysical properties were evaluated by TGA,DSC,UV-Vis and fluorescence spectroscopy,respectively.The weight-averaged molecular weights(Mw)of PS-DyCz and PS-DyF are 1.20×10^(4) and 3.83×10^(4) Da,respectively.The degree of polymerization is 8 and 22 units.Theseπ-conjugated polymers exhibited lower band-gap of 2.25 and 2.70 eV due to the presence of silole rings and C≡C triple bonds in their backbone,the results were consistent with the density functional(DFT)calculations at the B3LYP/6-31G^(*)level.

关键词： silole acetylene carbazole fluorene conjugated polymer density functional theory

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Distribution of n-alkanes in Miocene loess in Qinan, western Chinese Loess Plateau, and its palaeoenvironmental implications

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Science China Earth Sciences 2017年第5期60卷 921-928页

作者： SHEN JiaHeng xiao guoqiao WANG ZhiXiang SUN Qing WU HaiBin ZHANG ChunXia GUO ZhengTang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geosciences Wuhan 430074 China National Research Center of Geoanalysis Beijing 100037 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Neogene eolian successions are one of the most important terrestrial palaeoenvironmental archives in East Asia.However, they have received far less attention than Quaternary loess deposits, especially in the case of lipid biomarker analysis.In order to obtain a better insight into the early-middle Miocene palaeoenvironment, we conducted a study of n-alkane biomarkers from sediments of the QA-I section(Qinan) in the western Chinese Loess Plateau, and compared the results with those of previous n-alkane analyses of eolian and aquatic sediments of varying age. Our principal results are as follows:(1) All QA-I samples contain n-alkanes ranging from C_(14) to C_(35), among which the relative content of short-chain n-alkanes(C_(14)–C_(20)) from microorganisms is significantly greater than that of long-chain n-alkanes(C_(26)–C_(35)) from the waxes of terrestrial higher plants;the main peak is at C_(16)–C_(18). All samples have a relatively lower abundance of medium-chain n-alkanes(C_(21)–C_(25)) than that of long-and short-chain n-alkanes, similar to strongly weathered palaeosols in Quaternary loess and Late Miocene-Pliocene Hipparion Red-Earth; however, this distribution is significantly different from that in weakly-weathered loess of Quaternary loess and Late Miocene-Pliocene Hipparion Red-Earth, as well as from aquatic sediments.(2) Despite some odd-over-even carbon predominance of long-chain n-alkanes in the QA-I samples, the carbon preference index(CPI) values are significantly lower than those of most of the weakly-weathered sediments. Our results show that strong weathering and microbial processes have significantly altered the n-alkanes in the Miocene eolian deposits in Qinan, and led to a significant oxidation and degradation of long-chain n-alkanes and the predominance of short-chain n-alkanes from bacteria. Therefore, the contribution of microorganism to total organic carbon(TOC) and its resulting in carbon isotopic composition should be carefully assessed in future studies.

关键词：长链正构烷烃黄土高原古环境意义中中新世中国西部碳同位素组成水体沉积物微生物过程

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Evidence of late early Miocene aridification intensification in the Xining Basin caused by the northeastern Tibetan Plateau uplift

Evidence of late early Miocene aridification intensification...

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中国科学院地质与地球物理研究所2015年度（第15届）...

作者： Chunxia Zhang guoqiao xiao Zhengtang Guo Haibin Wu Qingzhen Hao Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Few early Miocene terrestrial climate records exist from the Asian interior and as a result the evolution of Central Asian aridification and the driving forces behind it remain unclear. Here we report sedimentary, mineralogy and geochemical proxies from an early Miocene sedimentary sequence(ca. 22.1 to 16.5 Ma) from Xining Basin on the northeastern side of the Tibetan Plateau. Multiple proxies indicate a change of sedimentary facies of a distal alluvial fan from subfluvial to subatmospheric under a dominantly arid climate coupled with a clear two-stage climate change. During 22.1–19.7 Ma(Unit I), the enrichment of I/S(irregular mixed-layers of illite and smectite) content, high values of a*/L*(redness/lightness), and stronger degree of chemical weathering suggest relatively warm and humid climate conditions during a generally arid climate. During 19.7–16.5 Ma(Unit II), the increase of chlorite and dolomite content, the upward decrease of a*/L*, and weaker degree of chemical weathering than Unit I suggest gradually increasing aridity since ca. 19.7 Ma. Comprehensive comparisons among records from central western China demonstrate that the aridification since ca. 19.7 Ma is widespread in northeastern part of the Tibetan Plateau. The climate changes in inner Asia are different to that of globalscale changes, which indicates that global climate changes and the retreat of the Para-Tethys Sea possibly had little influences on this region. The episodic, but persistent tectonic uplift of the north and northeastern Tibetan Plateau during the early Miocene likely played a key role in the aridification of the Xining Basin.

关键词： Inner Asia Early Miocene Clay minerals Aridification Tibetan Plateau uplift

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Detrital-Zircon Evidence for the Origin of the Late Quaternary Loess in Qingzhou， Shandong Province and Its Implications for the Evolution of the Yellow River

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Journal of Earth Science 2021年

作者： Shen Yanfei Liang Meiyan Wu Jianxun Peng Shuzhen xiao guoqiao Hubei Key Laboratory of Critical Zone Evolution， School of Geography and Information Engineering， China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology， School of Earth Sciences， China University of Geosciences School of Tourism， Resources and Environment， Taishan University

The loess depositions in Shandong Province are important parts of loess records in eastern China， but their origin and genetic linkage between the Yellow River and the Chinese Loess Plateau are still unclear. This paper presents the detrital-zircon evidence for the origin and provenance evolution of the Qingzhou loess in Shandong Province. The results show that: 1) the Qingzhou loess was sourced from the sandy lands within the North China Plain that was fed by the silty materials from the Chinese Loess Plateau， the mountainous region in Central Shandong Province， and the Yanshan and Taihang Mountains; 2) The Qingzhou loess was mainly sourced from the fluvial materials transported by the Yellow River， and the basal age of the Qingzhou loess indicates the timing of intensified aridification of the North China Plain and integration of the Yellow River was not later than 0.5 Ma; And 3) the provenance and grain-size of the Qingzhou loess underwent a significant transition at ～0.22 Ma， which was related to the expansion of the sandy lands within the North China Plain. Our results indicate that the origin of the loess on the North China Plain are obviously different from the loess on the Chinese Loess Plateau， and the increase of grain-size and accumulation rate in the loess records on the North China Plain at ～0.22 Ma was due to the environmental deterioration of the Eastern China.

关键词： North China Plain Loess Pleistocene Detrital-Zircon Yellow River

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