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U-series dating on late Quaternary sediments from Balikun Lake

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Chinese Science Bulletin 1998年第17期43卷 1434-1441页

作者： Jiaqi Liu zhibang ma Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

The U-series component-dating method has been employed to date the sediment core B-194 from Balikun Lake. 230Th/ 232Th and 234U/ 232Th ratios in various components of the samples dissolved in different concentration acids were measured respectively. The results indicate that there is a good relationship of the isotopic ratios between the solutions and the residues, and that uranium and thorium isotopic fractionations did not occur during acid leaching. Based on the U-series ages obtained by using component-dating method, a 144-ka time sequence was established corresponding to the upper 25-m interval of the B-194 core, which is in agreement with palaeomagnetic dating results. The fact that the palaeoclimatic and palaeoenvironmental record labeled with U-series ages is correlative with the deep-sea δ 18O SPECmaP also demonstrates that the U-series component-dating method can be used to date lake sediments.

关键词： Balikun Lake sediments component-dating model U-series age.

Centennial-scale monsoon collapses during marine Isotope Stage(MIS)7e detected in a northern Chinese stalagmite record

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Science China Earth Sciences 2023年第12期66卷 2941-2952页

作者： Wuhui DUAN Ming TAN Lisheng WANG Xuefeng WANG zhibang ma Linlin CUI Zhengyi XIAO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Beijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Occurrence or absence of centennial-scale climatic variability during marine Isotope Stage(MIS)7e,the first peak interval of the Penultimate Interglacial,remains ambiguous due to the limited available high-resolved ***,we present a decadal-resolved stalagmiteδ^(18)O record from northern China spanning from 242.3 to 236.8 ka BP,covering *** composite KLSδ^(18)O record,integrating this study with the previous record in the same cave,shows a descending trend from TerminationⅢto MIS7e,which follows the increasing Northern Hemisphere summer insolation(NHSI).This observation further emphasizes the important influence of NHSI on the glacial/interglacial *** are more large-amplitude,millennial-to centennial-scale variability occurring during TerminationⅢcompared with MIS7e,implying that ice-sheet decay potentially plays an important role in climatic *** centennial-scale summer monsoon collapses,peaking at~242.1,~240.8,~239.3 and~238.2 ka BP,are detected in our new record,indicating the pervasiveness of the intra-interglacial climatic *** the lack of solar activity and freshwater outbursts data during MIS7e,it is not possible to conclude about the drivers of the identified abrupt climatic *** the dynamic mechanisms of sub-millennial climatic anomalous during early Holocene,we tentatively propose that slowdown of the meridional overturning circulation caused by freshwater fluxes into North Atlantic and/or attenuated solar irradiance is the potential forcing for the abrupt climate events within ***,attenuated solar irradiance could also result in climatic anomalies through low-latitude processes.

关键词： Northern China Stalagmiteδ~(18)O record marine Isotope Stage(MIS)7e Centennial-scale monsoon collapses Freshwater and/or solar activity forcings

Sedimentary Characteristics and Paleoenvironmental Records of Zabuye Salt Lake,Tibetan Plateau,since 128 ka BP

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Acta Geologica Sinica(English Edition) 2007年第5期81卷 861-874页

作者： ZHENG Mianping YUAN Heran LIU Junying LI Yanhe ma zhibang SUN Qing Key Laboratory of Saline Lake Resources and Environment Ministry of Land and Resources Beijing 100037 Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 National Research Center of Geoanalysis Beijing 100037

This paper for the first time reveals high-resolution core records of Zabuye Salt Lake in the interior of the Qinghai-Tibet Plateau. According to 1346 samples taken continuously, relatively accurate 14^C, U-series disequilibrium and ESR ages have been obtained, thus revealing that the lake core ages from 0 to 83.63 m of hole SZK02 are -800 to over 128 ka. In the paper, the lake core sedimentary characteristics （including the lithologies and mineral assemblages） are analyzed in detail and correlated with ostracod assemblages I to XX and sporopollen zones A to I, and on the basis of an integrated analysis of the δ^18O values of authigenic calcium-magnesium carbonate and environmental proxies of minerals, sporopollen and microfossils in the lake core, a correlation has been made of oxygen isotope change between this lake core and the Greenland GISP2 and GRIP and Guliya ice cores, and the climate of Zabuye Salt Lake since 128 ka BP is divided into the last interglacial stage （including substages e, d, c, b and a） of oxygen isotope stage （OIS） 5, early glacial stadial of the last glacial stage of OIS 4, interglacial stadial of the last glacial stage of OIS 3, late glacial stadial of the last glacial stage or Last Glacial maximum of OIS 2 and postglacial state of OIS 1; in addition, 6 Heinrich （H6-H1） events, Younger Dryas event and 8.2 ka BP cold event have been recognized.

关键词： Zabuye Salt Lake 130 ka BP sedimentary characteristics paleoenvironmental record

High-precision U-series dating of Holocene corals from South China Sea by thermal ionization mass spectrometry(TIMS)

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Chinese Science Bulletin 1999年第10期44卷 937-941页

作者： zhibang ma Ming Xia Chenghui Zhang Zicheng Pen Zhaorong Wang Weidong Sun Zhisheng An Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China State Key Lab Loess & Quaternary Geol Xian 710054 Peoples R China

Using the isotopic diluting and thermal ionization mass spectrometric (TIMS) technique, the U-series dating procedure was established on the basis of measurement of national standard GBW04412. With this highly precise technique the Holocene corals from the South China Sea were dated. Comparison between this method and α-spectrometry was made. The results show that a thriving period of corals in the South China Sea appeared at 6 800—5 800 a BP, during which the paleosea level was the higher than at present in the Holecene.

关键词： Holocene corals reefs mass spectrometric U-series dating South China Sea.

High-precision timing of the Quaternary standard samples with thermal ionization mass spectrometry (TIMS) U-series method

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Chinese Science Bulletin 1998年第4期43卷 333-336页

作者： Peng Zicheng Wang Zhaorong Sun Weidong ma zhibang Xia Ming Zhang Chenhui Chen Wenji Zhang Zhonglu An Zhisheng Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China State Seismol Bur Inst Geol Beijing 100029 Peoples R China State Key Lab Loess & Quaternary Geol Xian 710054 Peoples R China

Two national stalagmite standard （GBW04412, GBW04413） and one international coral standard （RKM4） have been determined by using thermal ionization mass spectrometry （TIMS） method. The values of （ 234 U/ 238 U） act , （ 230 Th/ 234 U） act and age are all consistent in error range with the standard values obtained by using α spectrometry.

关键词： thermal ionization mass spectrometry (TIMS) U_series method standard samples stalagmite and coral age determination.

Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy lands) in northern China and their palaeoenvironmental implications

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Science China Earth Sciences 2019年第8期62卷 1302-1315页

作者： Xiaoping YANG Peng LIANG Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG Bing XU zhibang ma Qianqian LIU Xiaozong REN Fangen HU Yuxin HE Gang RAO Ninghua CHEN Department of Geography School of Earth SciencesZhejiang UniversityHangzhou310027China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Institute of Chinese Historical Geography Fudan UniversityShanghai200433China School of Geography Taiyuan Normal UniversityTaiyuan030619China College of Teachers’Education Yichun UniversityYichun336000China Department of Geology School of Earth SciencesZhejiang UniversityHangzhou310027China

This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely linked to human activities. The variable discharge of the Yellow River with diversions for irrigation may have resulted in a more consistent supply of aeolian particles for dune field expansion.(2) The dune landscape of the Hunshandake Sandy Land was likely formed around 12 ka, and before this, the western part of the Hunshandake Sandy Land would have been covered by a single large lake;it was obviously wetter than today in the sandy land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely time-transgressive across the region.(3) The palaeosol of the Hulunbuir Sandy Land began to develop as early as 14.5 ka, probably continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy lands) in northern China is spatially heterogeneous, and even the palaeosol development time in different locations within each sandy land is inconsistent. During the middle Holocen

关键词： Sand sea Sandy land,Environmental evolution,Kubuqi,Hunshandake,Hulunbuir

The palaeoenvironmental significance of δ13C of stalagmite BW-1 from Beijing, China during Younger Dryas intervals inferred from the grey level profile

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The palaeoenvironmental significance of δ13C of stalagmite ...

RESULTS OF AND DISCUSSION ON URANIUM-SERIES COMPARISON PROJECT IN CHINA

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： WUHUI DUAN MING TAN zhibang ma HAI CHENG Key Laboratory of Cenozoic Geology Environment Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Cenozoic Geology Environment Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Global Environmental Change Xi’an Jiaotong University Department of Earth Sciences University of Minnesota

High-resolution records of carbon isotope composition and grey level were analysed from a stalagmite, BW-1,from Beijing, China, deposited between c. 14 and 10.5 ka BP, the δ18O profile of which has been used to discuss the timing and structure of the Younger Dryas(YD) event in north China. The high grey level and low δ13C match the milk-white coloured locations on the polished stalagmite surface and coincide with enhanced luminescent bands within which the concentration of both impurities and the total organic carbon(TOC) are high. Additionally,the fluorescence of speleothems was derived from organic acids that have been flushed onto the stalagmite surface along with impurities from the overlying soil by heavy summer rain and co-precipitated with the speleothem calcite. Thus, predominantly low δ13C and high grey level values indicate increased summer precipitation that supports abundant vegetation and robust biological productivity. Consequently, three distinct time intervals are defined by the palaeoenvironmental conditions expressed in the δ13C and grey level records of stalagmite BW-1:(i) a warm-humid stage(Pre-YD, 13.97 to 12.85 ka BP, including a hiatus from 12.99 to 13.21 ka BP reported before);(ii) a cool-arid stage(YD, 12.85 to 11.56 ka BP);and(iii) a warm-humid stage(Post-YD,11.56 to 10.39 ka BP). The inferences based on our research are generally consistent with other regional vegetation and climatic records.

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Science in China,Ser.B 1987年第2期30卷 212-224页

作者：夏明张承蕙马志邦 Institute of Geology Academia Sinica Beijing

The results of a statistical analysis of the Uranium-series Comparison Project in China （USCP） haveshown that a good agreement among the participating laboratories has been achieved and that the analyt-ical techniques applied to dating of carbonate samples are correct. In regard to their consistency, theresults of the USCP in China are none the worse than those of the USIP-Ⅱ and Ⅲ. Some problems ofgreat interest in the field of uranium series disequilibrium geochronology are also discassed in this paper.

关键词： RESULTS OF AND DISCUSSION ON URANIUM-SERIES COMPARISON PROJECT IN CHINA Th

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西藏搭格架热泉型铯矿床年代学研究

岩石学报 2006年第3期22卷 717-724页

作者：赵元艺赵希涛马志邦中国地质科学院矿产资源研究所北京100037 中国科学院地质与地球物理研究所北京100029

西藏昂仁县搭格架地热田硅华中的铯达到超大型矿床规模,不同特征的热泉沉积或分布于冈底斯冰期冰碛物的外表或裂隙中,或覆于长马曲上游第5至第1级阶地及现代河床的不同部位。据热泉华野外分布的地貌部位和岩石学特征可将其分为6套。这6... 详细信息

西藏昂仁县搭格架地热田硅华中的铯达到超大型矿床规模,不同特征的热泉沉积或分布于冈底斯冰期冰碛物的外表或裂隙中,或覆于长马曲上游第5至第1级阶地及现代河床的不同部位。据热泉华野外分布的地貌部位和岩石学特征可将其分为6套。这6套泉华代表性样品的全溶法或等时线法U系测年结果表明:第1套泉华(钙华)形成于晚更新世晚期的末次冰期间冰阶晚期,相当于深海氧同位素第3阶段即MIS 3;第2套泉华(硅华)形成于中更新世晚期的倒数第二次冰期,相当于MIS 8～7;第3套泉华形成于晚更新世早期的末次间冰期,相当于MIS 5;第4套泉华(硅华)形成于晚更新世晚期的末次冰期间冰阶晚期至末次盛冰期早期,相当于MIS 3～2;第5套泉华(硅华)形成于晚更新世末期的末次盛冰期至全新世冰后期,相当于MIS 2～1;第6套泉华即现代硅华。参考前人的ESR年龄测定结果,可将搭格架热泉华的形成分为5个阶段:403～202ka BP,99ka BP左右,39～25ka BP,17～4ka BP与现代。在第3阶段硅华活动早期,有一次钙华活动。

关键词：热泉型铯矿 U系法测年中晚第四纪热泉活动分期西藏搭格架