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A study on the Dushiling tungsten-copper deposit in the Miao＇ershan-Yuechengling area, Northern Guangxi, China：Implications for variations in the mineralization of multi-aged composite granite plutons

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Science China Earth Sciences 2016年第11期59卷 2121-2141页

作者： CHEN WenDi ZHANG WenLan WANG RuCheng chu zhuyin XIAO Rong ZHANG Di CHE XuDong State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210093 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Huna. Institute of Geological Survey Changsha 410116China

The polymetallic Dushiling W-Cu deposit is a large, altered, skarn-type deposit, located in the northeastern part of the Miao'ershan-Yuechengling pluton, China. Two types of granite have been identified in the deposit: a medium-grained porphyritic biotite granite, and a medium- to fine-grained biotite granite. Both are spatially and temporally related to ore bodies, suggesting they may be the source of mineralization in the deposit. A medium- to fine-grained porphyritic biotite granite is exposed at the surface in the region of mineralization. U-Pb dating of zircons yielded magmatic ages of 423 Ma for the medium-grained porphyritic biotite granite and 421 Ma for the medium- to fine-grained porphyritic biotite granite, while a younger age(217 Ma) obtained for surface samples indicates later diagenesis. Thus, magmatism occurred during the Caledonian and Indosinian, respectively. The petrological and geochemical characteristics of the two Caledonian granites show that both are calc-alkaline and *** are moderately enriched in Cs, Rb, U, and REE, and strongly depleted in Sr,Ba,P,and Ti; they show similar REE behavior,including negative Eu anomalies. These geochemical similarities suggest that the two granites were derived from the same source,although they were emplaced during different stages of the evolution of the magma. Furthermore, the granites are associated with mineralization, suggesting they were the source of mineralization in the Dushiling W-Cu deposit. Sm-Nd ages of scheelite from the Dushiling W-Cu deposit indicate that metallogenesis occurred at 417±35 Ma, while the two types of titanite, intergrown with scheelite, yield U-Pb ages of 423–425 Ma(in altered granite sample) and 218 Ma(in skarn sample). These ages place the main mineralization event in the late Caledonian, and later magmatic-hydrothermal activity occurred in the Indosinian. The ages obtained for the Dushiling W-Cu deposit in the western Nanling Range, northern Yuechengling, togeth

关键词： Dushiling W-Cu deposit Ore-bearing granite Multi-aged mineralization Scheelite Sm-Nd dating Titanite U-Pb dating

Constraints on the Ediacaran-Cambrian boundary in deep-water realm in South China: Evidence from zircon CA-ID-TIMS U-Pb ages from the topmost Liuchapo Formation

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Science China Earth Sciences 2020年第8期63卷 1176-1187页

作者： Wei WANG Mingzhong ZHOU zhuyin chu Junjie XU Chaofeng LI Taiyi LUO Jinghui GUO State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China School of Geographical and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China:China University of GeosciencesBeijing 100083China:State Key Laboratory of Ore Deposit GeochemistryInstitute of GeochemistryChinese Academy of SciencesGuiyang 550002China

The placement of the Ediacaran-Cambrian boundary in deep-water realm in South China and the high-precision temporal framework for the Ediacaran-Cambrian transition in this region have not yet been completely solved. Recently, we have found two K-bentonite beds in the top of the Liuchapo Formation at the Pingyin section, Guizhou Province. It provides an opportunity for constructing the temporal framework of the transitional strata on the Yangtze Platform in South China and for determining the Ediacaran-Cambrian boundary in this area. In this study, we conducted high-precision CA-ID-TIMS U-Pb dating on zircons from the two K-bentonites. The ages of the two K-bentonites were precisely constrained at 536.40±0.47/1.1/1.2 Ma(2σ, n=7, MSWD=0.92) and 541.48±0.46/1.1/1.2 Ma(2σ, n=8, MSWD=1.3). Combining the geochronological results with organic carbon isotope data of chert in the topmost Liuchapo Formation from the section, we suggest that the EdiacaranCambrian boundary should be consistent with a significant negative organic carbon isotope excursion between the two Kbentonites. The scheme of the Ediacaran-Cambrian boundary in this study is of great significance for global correlation, and further for unravelling the information of the terminal Ediacaran-early Cambrian ocean.

关键词： Liuchapo Formation Yangtze Platform Ediacaran-Cambrian CA-ID-TIMS Organic carbon isotope

Archean-Paleoproterozoic Lithospheric Mantle at the Northern Margin of the North China Craton Represented by Tectonically Exhumed Peridotites

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2041-2057页

作者： TIAN Wei WANG Shuangyue LIU Fenglin chu zhuyin WANG Bin CHEN Mimi Jennifer PRICHARD Key Laboratory of Orogenic Belts and Crustal Evolution MOESchool of Earth and Space SciencesPeking University State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Research School of Earth and Space Sciences the Australian National University

Tectonically emplaced peridotites from North Hebei Province, North China Craton, have retained an original harzburgite mineral assemblage of olivine （54%-58%）＋ orthopyroxene （40%-46%）＋minor clinopyroxene （〈1%）＋spinel. Samples with honinite-like chemical compositions also coexist with these peridotites. The spinels within the peridotites have high-A1 end-members with A1203 content of 30 wt%-50 wt%, typical of mantle spinels. When compared with experimentally determined melt extraction trajectories, the harzburgites display a high degree of melting and enrichment of SiO2, which is typical of cratonic mantle peridotites. The peridotites display variably enriched light rare earth elements （REEs）, relatively depleted middle REEs and weakly fractionated heavy REEs, which suggest a melt extraction of over 25% in the spinel stability field. The occurrence of are- and SSZ-type chromian spinels in the peridotites suggests that melt extraction and metasomatism occurred mostly in a subduction-related setting. This is also supported by the geochemical data of the coexisting boninite-like samples. The peridotites have lS7Os/lSSOs ratios ranging from 0.113-0.122, which is typical of cratonic iithospheric mantle. These lSTOs/ISSOs ratios yield model melt extraction ages （TRD） ranging from 981 Ma to 2054 Ma, which may represent the minimum estimation of the melt extraction age. The Ai203- lSTOs/lSSOs-proxy isochron ages of 2.4 Ga-2.7 Ga suggest a mantle melt depletion age between the Late Achaean and Early Paleoproterozoic. Both the peridotites and boninite-like rocks are therefore interpreted as tectonically exhumed continental lithospheric mantle of the North China Craton, which has experienced mantle melt depletion and subduction-related mantle metasomatism during the Neoarchean- Paleoproterozoic.

关键词： harzburgite boninite Re-Os isotopes lithospheric mantle Paleoproterozoic North China Craton

Revisiting Rhenium-Osmium Isotopic Investigations of Petroleum Systems: From Geochemical Behaviours to Geological Interpretations

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Journal of Earth Science 2021年第5期32卷 1226-1249页

作者： Shao-Jie Li Xuan-Ce Wang Simon A.Wilde zhuyin chu Chaofeng Li Sheng He Keyu Liu Xingzhi Ma Yuxiang Zhang School of Earth Sciences Yunnan UniversityKunming 650500China The School of Earth Science and Resources Chang'an UniversityXi'an 710054China ARC Centre of Excellence for Core to Crust Fluid Systems and The Institute for Geoscience Research Department of Applied GeologyCurtin UniversityPerth 6845Australia State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China School of Geosciences China University of Petroleum(Huadong)Qingdao 266555China PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China Australise Resources and Environment Solutions Wattle GrovePerth 6107Australia

Recent decades have witnessed an increasing number of studies investigating petroleum systems with the application of rhenium-osmium(Re-Os) isotopic geochemistry. Here, we review the use of the 187 Re-187 Os geochronometer with respect to the geochemical behaviour of rhenium and osmium in hydrocarbon-related geological processes. The Re-Os budget in hydrocarbon source rock predominantly originates from natural water columns during its deposition. Open seawater tends to have a homogeneous Os isotopic composition because its residence time in seawater is longer than the time taken for ocean mixing. On the contrary, restricted water bodies(e.g., lakes) may have heterogeneous Os isotopic compositions due to the greater amount of terrigenous input. Hydrogenous Re and Os atoms are sequestered from the water body into sedimentary organic matter and transferred into crude oil through thermal maturation of organic matter. Thermal maturation likely does not significantly alter the Re-Os isotopic systematics of the source rock as a Re-Os isochron age of 442±21 Ma(2σ) is yielded in this study for over matured source rocks within the Silurian Longmaxi Formation from the Sichuan Basin. Re-Os atoms are mainly hosted by the highly polar/aggregating/aromatic asphaltenes in hydrocarbons, possibly chelating with organic complexes or occurring as metalloporphyrins. Resin and aromatic hydrocarbons also contribute to the Re-Os budget, but are 2 to 3 orders of magnitude lower than that of asphaltenes, whereas saturates do not contain appreciable Re-Os contents. The distribution of Re-Os atoms in hydrocarbons is heterogeneous because the duplicate analysis of pure single bitumen samples yields similar ^(187)Os/^(188)Os ratios whereas variable ^(187)Re/^(188)Os ratios. The Re-Os system in crude oils can be reset during transport away from the source rocks, with Os-rich organic fractions more readily expelled than Re-rich fractions. Contact with metal-rich fluids(e.g., hydrothermal fluid) or

关键词： Re-Os isotope system petroleum system investigation geochemical behaviour of Re and Os in petroleum system

Alkaline Intrusives at the East Foot of the Taihang-Da Hinggan Mountains:Chronology,Sr,Nd and Pb Isotopic Characteristics and Their Implications

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Acta Geologica Sinica(English Edition) 2000年第4期74卷 774-780页

作者： YAN Guohan XU Baoliang MU Baolei WANG Guanyu CHANG Zhaoshan CHEN Tingli ZHAO Yongchao WANG Xiaofang ZHANG Renhu QIAO Guangsheng chu zhuyin Department of Geology Peking UniversityBeijing 100871 Institute of Geology Chinese Academy of SciencesBeijing 100029

Based on the Rb-Sr isochron dating results, this paper suggests that the alkaline intrusive belt at the east foot of the Taihang-Da Hinggan Mountains were formed between 135 and 122 Ma. And the alkaline intrusives in the north and south sections of this belt have entirely different Sr, Nd and Pb isotopic characteristics, i.e., all the rocks in the south section have positive εSr(t) and negative εNd(t) values and all those in the north have the opposite values. On the εSr(t) versus εNd(t) correlation diagram, the samples from the south are concentrated along the enriched mantle evolution trend lines and nearby, while those from the north fall along the depleted mantle trend lines and nearby. On the Pb isotope composition diagram, most of the samples from the south section fall on the mantle Pb evolution line and nearby, while those from the north lie between the Pb evolution lines of the mantle and the erogenic belt. The above-stated isotopic characteristics not only indicate that the source rocks of the alkaline intrusives in the south section have a close connection to materials from the enriched mantle reservoir, while those in the north are related to materials from the depleted one, but also reveal that the upper mantle below the North China platform is enriched and that below the Inner Mongolia geosyncline is depleted.

关键词： alkaline intrusives chronology Sr Nd and Pb isotopes east foot of the Taihang-Da Hinggan Mountains

铼—锇同位素和铂族元素分析方法及地学应用进展

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地球科学进展 2021年第3期36卷 245-264页

作者：储银许继峰中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国地质大学地球科学和资源学院北京100083

近30年来,国内外铼—锇(Re-Os)同位素和铂族元素(PGE)分析方法及其地学应用取得了诸多研究进展。首先对铼—锇同位素和铂族元素分析的样品溶解、化学分离及质谱测定等方面的进展情况进行了综述;然后,对铼—锇同位素和铂族元素在天体化... 详细信息

近30年来,国内外铼—锇(Re-Os)同位素和铂族元素(PGE)分析方法及其地学应用取得了诸多研究进展。首先对铼—锇同位素和铂族元素分析的样品溶解、化学分离及质谱测定等方面的进展情况进行了综述;然后,对铼—锇同位素和铂族元素在天体化学、大陆岩石圈地幔定年、金属矿床定年、沉积地层定年及古环境,以及在油气系统定年与示踪等领域的应用进展情况进行了简要评述。可供地质分析工作者针对不同分析任务及分析对象,选择分析方法并进一步发展Re-OsPGE分析技术时参考,也可供地质科研工作者开展Re-Os-PGE地球化学研究工作时借鉴。

关键词：铼—锇同位素铂族元素分析方法地学应用

Determination of Re, Os, Ir, Ru, Pt, Pd low Mass Fractions and 187Os/188Os Ratios of Organic-Rich Geological Reference Materials

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Determination of Re, Os, Ir, Ru, Pt, Pd low Mass Fractions a...

Precise Determination of Sm and Nd Concentrations and Nd Isotopic Compositions in Highly Depleted Ultramafic Reference Materials

作者： Mengjie Wang zhuyin chu Thomas Meisel Jinghui Guo

The Re-Os-PGE systems of organic-rich geological samples (ORGS) have been widely applied in geochemistry. Nevertheless, at current, the reported data for Re-PGE mass fractions and 187Os/188Os isotope ratios of the organic-rich reference materials (RMs), in particular the PGE mass fraction data are rare, hampering the comparison of data quality between different laboratories. In this study, five organic-rich RMs,

关键词： Determination of Re Pd low Mass Fractions and 187Os/188Os Ratios of Organic-Rich Geological Reference Materials

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Precise Determination of Sm and Nd Concentrations and Nd Iso...

^(207)Pb/^(206)Pb determination of zircons by laser probe-inductively coupled plasma mass spectrometry

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： zhuyin chu Jinghui Guo Yueheng Yang Liang Qi Chaofeng Li State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences

In this study,a high-precision method for the determination of Sm and Nd concentrations and Nd isotopic composition in highly depleted ultramafic rocks without a preconcentration step is *** samples were first digested using the conventional HF+HNO3+HCl O4method,followed by the complete digestion of chromite in the samples using HCl O4at 190–200°C and then complete dissolution of fluoride formed during the HF decomposition step using *** steps ensured the complete digestion of the ultramafic *** rare earth elements(REEs)were separated from the sample matrix using conventional cation-exchange chromatography;subsequently,Sm and Nd were separated using the LN *** isotopes were determined as Nd O+,whereas Sm isotopes were measured as Sm+,both with very high sensitivity using single W filaments with Ta F5as an ion *** highly depleted ultramafic rock reference materials including USGS DTS-1,DTS-2,DTS-2b,PCC-1 and GSJ JP-1,which contain extremely low amounts of Sm and Nd(down to sub ng g-1level),were analysed,and high-precision Sm and Nd concentration and Nd isotope data were *** is the first report of the Sm-Nd isotopic compositions of these ultramafic rock reference materials except for PCC-1.

关键词： ultramafic rocks sample digestion isotope dilution thermal ionisation mass spectrometry isotope ratios reference materials.

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Chinese Science Bulletin 1998年第23期43卷 2008-2012页

作者： YAN Xin\+1, chu zhuyin\+1, SUN Min\+2, XU Ping\+1 and ZHOU Xinhua\+11. Institute of Geology, Chinese Academy of Sciences, Beijing 100029, China 2. Department of Geosciences, Hong Kong University, Hong Kong, China Institute of Geology Chinese Academy of Sciences Beijing China Department of Geosciences Hong Kong University Hong Kong China

Laser probe_inductively coupled plasma mass spectrometry (LP_ICP_MS) was used to determine 207 Pb/ 206 Pb ratios in single zircon grains. A Nd∶YAG laser operating at 1 064 nm and a Fisons_VG PQII Turbo ICP_MS were employed. For the known zircons, the 207 Pb/ 206 Pb results of LP_ICP_MS are close to the thermal ionization mass spectrometry (TIMS) results. The spatial resolution of this method is 40-50 μm and the sensitivities for lead isotopes are about 300-400 cps/ppm. The precision of 207 Pb/ 206 Pb ratio is 0.3%-4% and depends on the lead concentration of the sampling pits. LP_ICP_MS provides a simple, rapid and economic method for zircon 207 Pb/ 206 Pb determination.

关键词： laser probe_inductively coupled plasma mass spectrometry zircon microanalysis.