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Chang’e-5 samples reveal two-billion-year-old volcanic activity on the Moon and its source characteristics

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Science China Earth Sciences 2021年第12期64卷 2083-2089页

作者： Shoujie liU Qin ZHOU qiuli li Sen HU Wei YANG Institute of Geology Chinese Academy of Geological SciencesBeijing100037China National Astronomical Observatories Chinese Academy of SciencesBeijing100101China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing100029China

The Chang’e-5 mission returned new lunar samples after the last sample mission of the Moon 44 years ago,and is also the first mission that China has completed the sampling of extraterrestrial ***,independent teams from the Institute of Geology,Chinese Academy of Geological Sciences,and the National Astronomical Observatories and the Institute of Geology and Geophysics,Chinese Academy of Sciences reported the first batch of results of Chang’e-5 lunar *** basic physical properties of the Chang’e-5 soil are within the range of the Apollo and Luna samples though the Chang’e-5 soil is finer-grained,better sorted,and has a slightly lower true density than the mare basalt previosuly *** Pb-Pb dating of U-rich minerals in the Chang’e-5 basalt clasts indicated that they formed at about 2.0 Ga,800 million years younger than the youngest lunar sample recovered previously(2.8 Ga),confirming that lunar volcanic activity can last at least until 2 ***-situ Sr-Nd isotope analyses suggested that the Chang’e-5 basalt originated from a depleted mantle *** contribution of the KREEP component is less than 5%,which excluded the hypothesis that KREEP-rich sources provide an additional heat source for mantle *** addition,water contents and H isotopes of apatite and melt inclusions of the Chang’e-5 basalt suggested that the source region is not rich in water which can lower the melting ***,the reason why lunar volcanic activity can last so long is still unclear,which is a new direction for future lunar exploration and research.

关键词： Chang'e-5 Lunar soil Basalt Pb-Pb dating Sr-Nd isotopes Water H isotope

Nd isotopic disequilibrium between minerals and Rb-Sr age of the secondary phengite in eclogite from the Yangkou area,Qingdao,eastern China

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Chinese Science Bulletin 2001年第3期46卷 252-255页

作者： li Shuguang SUN Weidong ZHANG Zongqing li qiuli Chemical Geodynamics Laboratory Department of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

There are two generations of white micas in retrograded coesite-bearing eclogite from the Yangkou area near Qingdao, eastern China. The secondary phengite developed along the folliations in eclogite is the majority of the white micas. Nd and Sr isotopic disequilibriums between garnet and retrograded omphacite as well as secondary phengite have been observed. Consequently, the Rb-Sr ages ((193±4) Ma-(195±4) Ma) given by the tie lines of the secondary phengite + garnet or whole rock may predate the formation time of the phengite. The Rb-Sr age of (183±4) Ma given by the secondary phengite + retrograde omphacite is much closer to the formation time of the phengite indicating the retrograde age of eclogite instead of a cooling age of eclogite at 500℃.

关键词： eclogite Nd isotopic disequilibrium Rb-Sr dating Su-Lu UHPM belt.

Long-Term Reproducibility of SIMS Zircon U-Pb Geochronology

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Journal of Earth Science 2022年第1期33卷 17-24页

作者： Wenhao Zhao qiuli li Yu liu Guoqiang Tang Xiaoxiao ling Jiao li Xianhua li State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China

Secondary ion mass spectrometry(SIMS) zircon U-Pb dating has been widely used to confine the absolute ages of the magmatic or metamorphic events and to distinguish multiple ***,a data set consisting of the zircon standards dating data(~15 000 Ple?ovice and ~8 000 Qinghu items) accumulated for more than 8 years using the CAMECA IMS 1280 HR of the Institute of Geology and Geophysics,Chinese Academy of Sciences(IGGCAS) is compiled to evaluate the long-term external *** Ple?ovice zircon as the calibration standard and Qinghu zircon as an unknown sample,the analytical uncertainties for single-spot(n = 7 723) and session analyses(n = 691,with more than 7 single spot analyses in one session) are 2.6% and 0.9%(2 RSD,relative standard deviation),*** means that single-spot U-Pb dating for a standard-level zircon sample could vary 5.2% at 95% confidence level,while the average value(n > 7) for each session may vary 1.8%.Thus,these values should be considered as the minimum uncertainty when comparing single spot and individual session analysis results for multiple dating works on a certain geological event.

关键词： zircon U-Pb dating SIMS uncertainty reproducibility

U-Pb dating of bastnäsite from the Vuoriyarvi massif:An example application for assessing the REE potential of carbonatite-related deposits

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Geoscience Frontiers 2024年第5期15卷 444-453页

作者： Evgeniy N.Kozlov Ekaterina N.Fomina qiuli li Jiao li Geological Institute Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline *** carbonatites of the Vuoriyarvi massif contain abundant rare-earth mineralization mainly represented by ancylite-(Ce)and bastnäsite-(Ce).Ancylite was previously shown to have probably formed in the Devonian(ca.365 Ma)during an early postmagmatic *** geological observations have revealed a much later crystallization of bastnäsite but have not been able to specify the exact age of the *** in situ U-Pb dating of bastnäsite allowed us to constrain its ***äsite for this study was extracted from two varieties of dolomite carbonatite breccias cemented by(1)quartz-bastnäsite and(2)strontianite aggregates(hereafter bastnäsite-rich and strontianite-rich carbonatites–BRC and SRC,respectively).The obtained age estimations(237.7±9.8 Ma and 239.9±4.1 Ma,respectively)indicate that both studied rocks were formed during a single *** revealed age difference(~125 Ma)excludes the genetic link between the bastnäsite origin and regional alkaline magmatism,pointing out an additional source for the Vuoriyarvi bastnäsite-bearing ***,the obtained U-Pb ages provide strong evidence that a Triassic event is responsible for the occurrence of bastnäsite mineralization due to hydrothermal REE redistribution from the Devonian ancylite-rich *** of the REEs released during this process via dissolution of ancylite were precipitated in situ as bastnäsite,while strontium was transported and incorporated into *** Pb isotopic characteristics of bastnäsite(^(206)Pb/^(204)Pb=18.1±0.1,^(207)Pb/^(204)Pb=15.3±0.1,and^(207)Pb/^(206)Pb=0.84±0.01)are most probably inherited from the Devonian host rocks of the Vuoriyarvi massif involved in the Triassic *** signatures of Pb,Sr,and Nd show that the depleted mantle and lower crust played the leading role in formation of the Vuoriyarvi alkaline

关键词： Bastnäsite REE Carbonatites U-Pb dating Vuoriyarvi Kola alkaline province

Ultra-low procedural blank and the single-grain mica Rb-Sr isochron dating

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Chinese Science Bulletin 2005年第24期50卷 2861-2865页

作者： li qiuli HEN Fukun WANG Xiuli li Xianghui li Chaofeng State Key Laboratory of lithosphere Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China School of Earch Sciences Graduate University of Chinese Academy of Sciences Beijing 100039 China

Both low procedural blank and high-precision measurements of isotopic ratios are crucial for the analysis of micro samples. This study reports a chemical procedure of ultra-low blank for the high precision measurement of Sr isotopic ratios on micro samples (lite in liaoning Province. This method can be employed in studies of high resolution Rb-Sr geochronology and Sr isotopic geochemistry and thus will broaden application of the Rb-Sr isotopic system to earth sciences.

关键词：地球科学同位素比稳定同位素地球化学云母角砾云橄岩 Rb-Sr同位素测年

Analysis of entropies based on empirical mode decomposition in amnesic mild cognitive impairment of diabetes mellitus

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Journal of Innovative Optical Health Sciences 2015年第5期8卷 11-30页

作者： Dong Cui Jinhuan Wang Zhijie Bian qiuli li Lei Wang Xiaoli li School of Information Science and Engineering Yanshan University QinhuangdaoP.R.China School of Electrical Engineering Yanshan University QinhuangdaoP.R.China Department of Neurology General Hospital of Second Artillery Corps of PLA Beijing P.R.China State Key Laboratory of Cognitive Neuroscience and Learning&IDG/McGovern Institute for Brain Research Beijing Normal University BeijingP.R.China Center for Collaboration and Innovation in Brain and Learning Sciences Beijing Normal University BeijingP.R.China

EEG characteristics that correlate with the cognitive functions are important in detecting mild cognitive impairment(MCI)in *** investigate the complexity between aMCI group and age-matched non-aMCI control group in T2DM,six entropies combining empirical mode decomposition(EMD),including Approximate entropy(ApEn),Sample entropy(SaEn),Fuzzy entropy(FEn),Permutation entropy(PEn),Power spectrum entropy(PsEn)and Wavelet entropy(WEn)were used in the study.A feature extraction technique based on maximization of the area under the curve(AUC)and a support vector machine(SVM)were subsequently used to for features selection and classi¯***,Pearson's linear correlation was employed to study associations between these entropies and cognitive *** to other entropies,FEn had a higher classification accuracy,sensitivity and specificity of 68%,67.1% and 71.9%,*** 43 salient features achieved classification accuracy,sensitivity and speci¯city of 73.8%,72.3% and 77.9%,respectively.P4,T4 and C4 were the highest ranking salient *** analysis showed that FEn based on EMD was positively correlated to memory at electrodes F7,F8 and P4,and PsEn based on EMD was positively correlated to Montreal cognitive assessment(MoCA)and memory at electrode *** sum,FEn based on EMD in righttemporal and occipital regions may be more suitable for early diagnosis of the MCI with T2DM.

关键词： Entropy empirical mode decomposition amnestic mild cognitive impairment type 2 diabetes mellitus

Mesozoic “Red Beds” and its Evolution in the Hefei Basin

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1060-1076页

作者： ZHANG Jiaodong CHEN Xuanhua li qiuli liU Chengzhai li Bing li Jie liU Gang REN Fenglou Chinese Academy of Geological Sciences Beijing 100037China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Shengli Oil Company Dongying 257100China

The Hefei Basin is the largest basin in the North China landmass with complete and well-preserved Mesozoic and Cenozoic strata. In the basin there developed a suite of extremely thick ＂red beds＂ in the Mesozoic. Owing to complex evolution processes and a lack of paleontological traces, there have been controversies regarding the division and correlation of this suite of red beds. Based on results obtained in recent years in drilling, seismic and surface geological investigations and in consideration of relationships between seismic sequences and regional tectonic events, as well as evidence in paleontology, petrology and isotopic dating, this paper preliminarily puts forward the following ideas about the sequence stratigraphic framework of the continental ＂red beds＂ in the Hefei Basin. （1） The Zhougongshan Formation and the Yuantongshan Formation have similar lithologic, geophysical and paleontological characteristics, so we incorporate them into a single formation, called the Yuantongshan Formation, and the original Zhougongshan and Yuantongshan Formations are regarded as the upper and the lower parts of the newly defined Yuantongshan Formation. Its age is the Middle Jurassic; （2） the Zhuxiang Formation belongs to the Upper Jurassic Series and （3） the age of the Xiangdaopu Formation is the Lower Cretaceous. Furthermore, signatures of depositional evolution are analyzed in the paper based on features of seismic reflection, outcrops and drilling data. The Early and Middle Jurassic is characterized by a foreland basin, which is influenced mainly by uplift and longitudinal compression of the Dabieshan Mountains; the Lower Jurassic System has a relatively small depositional area; the Middle Jurassic strata are distributed extensively over the whole basin, marking the summit of basin development; a flexure basin is characteristic of the Late Jurassic, manifesting a joint effect of the Dabieshan and Zhangbaling Mountains with the former being more significant. In the Earl

关键词： Mesozoic Erathem red beds sequence stratigraphic framework depositional evolution Hefei Basin

Insights into the origin of purely sediment-derived Himalayan leucogranites:Si-O isotopic constraints

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Science Bulletin 2018年第19期63卷 1243-1245页

作者： Xiaochi liu Xianhua li Yu liu Lei Yang qiuli li Fuyuan Wu Huimin Yu Fang Huang State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China

Granite is the dominant rock type in Earth’s continental *** origin of granite can be directly or indirectly related to the fractional crystallization of mantle-derived basaltic melt or the reworking of pre-existing continental or oceanic crust, which contribute to the growth of continental crust. Among the various types of granites, the peraluminous leucogranites in the Himalayan orogen, which are high in SiO_2(>73%) and low in mafic minerals (<5%),

关键词：起源同位素沉积岩石类型花岗石外壳大陆玄武岩

Multiple thermal events recorded in the Acasta Gneiss Complex:Evidence from in-situ dating of zircon, titanite, and apatite

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Science China Earth Sciences 2024年第3期67卷 673-686页

作者： Qingfeng MEI Jinhui YANG Jinfeng SUN qiuli li Shitou WU Xiaoxiao liNG Peng PENG Hao WANG State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China

In-situ dating of the zircons, titanites, and apatites in the rock fragments of approximately 1 cm2in size from the Acasta Gneiss Complex was performed using secondary ion mass spectrometry or laser ablation inductively coupled plasma mass spectrometry to provide constraints on the thermal history of the Acasta Gneiss Complex. The zircons in these rock fragments typically exhibit multiple age populations, reflecting the presence of inherited zircons or the post-crystallization process of zircon overgrowth. Combined with previous studies, our zircon dating results reveal multiple magmatic events that occurred in the Acasta Gneiss Complex, specifically at >3.96, ~3.72, and ~3.57 Ga, respectively. A titanite Pb-Pb isochron age of2911±22 Ma(95% confidence level, MSWD=1.5) for sample AY199 is identified, consistent with the timing of the latest Archean magmatism in the Acasta Gneiss Complex. The titanite U-Pb ages for samples AC478 and AY066 are 1932±270 Ma(95% confidence level, MSWD=2.3) and 1813±45 Ma(95% confidence level, MSWD=2.3), respectively. The apatites in sample P090803-C exhibit a Pb-Pb isochron age of 1833±26 Ma(95% confidence level, MSWD=1.4). The apatite U-Pb ages for samples AC478, AY199, and AY066 are 1850±20 Ma(95% confidence level, MSWD=1.3), 1827±100 Ma(95% confidence level, MSWD=6.3), and 1807±58 Ma(95% confidence level, MSWD=3.9), respectively. Titanites in samples AC478 and AY066, as well as the apatites in all four investigated samples, show a uniform age(Pb-Pb or U-Pb age) of ~1.9–1.8 Ga,indicating U-Pb system reset in these minerals due to the Wopmay orogeny and documenting that the peak temperature condition associated with the Wopmay orogeny exceeded the apatite U-Pb closure temperature and approached or exceeded that of titanite.

关键词： Zircon Titanite Apatite Acasta Gneiss Complex Wopmay Orogen