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| 1 | ^(40)Ar-^(39)Ar Isotopic Dating of the Xianghualing Sn-polymetallic Orefield in Southern Hunan,China and Its Geological Implications显示文摘摘要:在湖南省的 Xianghualing Sn-polymetallic orefield,南部的中国,是大尺寸的听 orefield。尽管众多的研究在这 orefield 上被承担了,它的开始,矿化作用年龄,和构造背景仍然是争论的,主要因为听矿化作用上的可靠 geochronological 数据的缺乏。40Ar/39 Ar 标明日期方法的逐步的加热首先在这 orefield 从不同存款在白云母上被采用。从 Xianghualing Sn-polymetallic 存款的白云母样品定义 154.4 | YUAN Shunda PENG Jiantang SHEN Nengping HU Ruizhong DAI Tongmo | 2007 | Acta Geologica Sinica(English Edition)2007，81，2： | 76 |
| 2 | Timing of Uranium Mineralization and Geological Implications of Shazijiang Granite-Hosted Uranium Deposit in Guangxi, South China: New Constraint from Chemical U-Pb Age显示文摘Miaoershan (MES ) 铀矿石地是在中国的最重要的铀来源,之一和许多另外的招待花岗石的铀存款在华南招待最大的 Chanziping carbonaceous-siliceous-pelitic 岩石类型铀存款。Shazijiang (SZJ ) 铀存款是 MES 铀矿石地里的代表性的招待花岗石的铀存款之一,位于 Ziyuan, Guangxi 省,华南。在 SZJ 存款的铀矿化作用主要与空间地在这个区域与 mafic 女同性恋被联系的石英和方解石静脉作为沥青铀矿发生。热水的改变包括 silicification,碳酸饱和和 hematitization。新沥青铀矿化学药品 U-Pb 地球年代学和 petrographic 证据提供预定限制和新卓见进 SZJ 铀存款的形成。第一铀矿化作用上演的结果表演在 97.5 湯漠 ? 桴 ? 敚慤杮愠摮 ? 潵畢慳瀠牥摩瑯瑩獥椠 ? 潣獮獩整瑮眠瑩 ? 潢桴愠祢獳污愠摮猠'T 畤瑣潩 ? | Jincheng Luo Ruizhong Hu Shaohua Shi | 2015 | Journal of Earth Science2015，26，6： | 21 |
| 3 | Sm-Nd isotope dating of hydrothermal calcites from the Xikuangshan antimony deposit,Central Hunan显示文摘The research on Samarium-Neodymium isotope systematics of hydrothermal calcites from the Xi-kuangshan antimony deposit, Central Hunan, places precise timing constraints on the Sb mineralization in this area. It is revealed that the Xikuangshan deposit formed during the late Jurassic-early Cretaceous Period, the early- and late-stage mineralization took place at (155.5±1.1) Ma and (124.1±3.7) Ma, respectively. The accurate age determination of mineralization is very crucial for revealing the super-enrichment mechanism of the element Sb at the Xikuangshan mine, and lays some foundations for the further understandings of its ore genesis and mineralization mechanism. | PENG Jiantang HU Ruizhong LIN Yuanxian ZHAO Junhong | 2002 | Chinese Science Bulletin2002，47，13： | 19 |
| 4 | Characteristics of rare-earth elements (REE),strontium and neodymium isotopes in hydrothermal fluorites from the Bailashui tin deposit in the Furong ore field,southern Hunan Province,China显示文摘In this paper the authors present the REE concentrations and Sr and Nd isotopic compositions of fluorites from the Bailashui tin deposit of the Furong ore field,southern Hunan Province. The results showed that the total amount of REE in fluorites is usually low,ranging from 0.705 to 8.785 μg/g with the chondrite-normalized REE dis-tribution patterns similar to those of the Qitianling granites in the study area,characterized by LREE-enrichment patterns with pronounced negative Eu anomalies. The fluorites vary in Sr isotopic composition within the range of 0.7083-0.7091,the values are lower than those of the granites and higher than those of the host carbonate rocks in this area. The εNd(t) values of fluorites vary between -9.4 and +10.3,revealing that both the crust-and mantle-source materials were involved in the ore-forming hydrothermal fluids. Combined with previous studies on this ore deposit,the Bailashui tin deposit is temporally and spatially closely related with granitic magmatism in this area. The hydro-thermal fluorites are the product of fluid/rock interactions between granitic magmatic hydrothermal fluid and marine carbonate rocks. The REE and F in the ore-forming fluid were derived from the granites,whereas Sr in the ore-forming fluid came mainly from the granitic magmatic hydrothermal fluid and marine carbonate rocks,although variations in Sr isotopic composition cannot be explained by a simple mixture of these two end-members. Evidence demonstrated that the ore-forming fluids are of crustal-mantle mixing origin,but that the fluids were probably in-completely homogenized and this may be caused by inhomogeneous mixing of the fluids of different sources. | YUAN Shunda PENG Jiantang HU Ruizhong BI Xianwu QI Liang LI Zhaoli LI Xiaomin SHUANG Yan | 2008 | Chinese Journal Of Geochemistry2008，27，4： | 16 |
| 5 | Os isotopic compositions of a cobalt-rich ferromanganese crust profile in Central Pacific显示文摘187Os/188Os ratios in all sub-layers of the Co-rich ferromanganese crust MP5D17 from Line Seamount in Central Pacific have been systematically determined. The 187Os/188Os values in this crust are highly variable, ranging from 0.4262 to 1.0155. From the bottom to the top, the os-mium isotopic ratios of the crust display a regular variation trend, which correlates well with its changes in structure and texture in the vertical profile. In comparison with the evolu-tion curve of Os isotopic composition in seawater over the past 80 Ma, a similar evolution tendency can be found with respect to the Os isotopic composition of the crust in this study. It is preliminarily concluded that the crust MP5D17 began to grow at about 72 Ma, and underwent three growth hiatuses, corresponding to the geological ages of 64, 53 and 37 Ma, respectively. | FU Yazhou PENG Jiantang QU Wenjun HU Ruizhong SHI Xuefa DU Andao | 2005 | Chinese Science Bulletin2005，50，18： | 13 |
| 6 | Jurassic Intra-plate Basaltic Magmatism in Southeast China:Evidence from Geological and Geochemical Characteristics of the Chebu Gabbroite in Southern Jiangxi Province显示文摘Geochemical and isotopic investigations have been carried out on the Chebu gabbroite in southern Jiangxi Province, southeast China and these results are compared with gabbro bodies along the coast of Fujian Province in order to understand their magma sources and tectonic implications. The Chebu intrusion formed at the beginning of the Middle Jurassic (172±4.3 Ma). These rocks are Ti-rich and Al-poor in major elements, characterized by strong enrichment in large-ion lithophile elements (LILE) and moderate enrichment in high field strength elements (HFSE) and light rare-earth elements (LREE), without pronounced Nb or Ta anomalies. Age-correlated Sr-Nd isotope ratios show moderately high ranges of (87Sr/86Sr)i from 0.7065 to 0.7086 and 0.5124 to 0.5125 of (143Nd/144Nd)i. The geochemical characteristics of the Chebu gabbroite suggest that it is notably different from island-arc basalt and similar to intra-plate basaltic rocks. By combining interpretations of its geological and geochemical characteristics and the regional geological development history, the Chebu gabbroitic intrusion is thought to be the product of asthenosphere upwelling and rapid lithosphere extension during a transition of tectonic systems in southeast China. The tectonic environment and source characteristics of the intrusion are different from Cretaceous gabbro bodies along the coast of Fujian Province, The former formed in a tectonic environment of rapid intra-plate lithospheric extension and the source characteristics were of a weakly enriched primitive mantle, whereas the latter originated mainly in a volcanic-magmatic arc extensional tectonic environment and the nature of the source was an enriched mantle with more subduct subducted components. | XIE Guiqing MAO Jingwen HU Ruizhong LI Ruiling JIANG Guohao CAO Jinjian ZHAO Junhong | 2005 | Acta Geologica Sinica(English Edition)2005，79，5： | 10 |
| 7 | Mineral Geochemical Compositions of Tourmalines and Their Significance in the Gejiu Tin Polymetallic Deposits, Yunnan, China显示文摘The Gejiu tin polymetallic deposits are located in the southeastern part of Yunnan Province in China. A detailed electronic microprobe study has been carried out to document geochemical compositions of tourmalines from the deposits. The results indicate a systematic change of mineral geochemical compositions, which might be used as a mineral geochemical tracer for post-magmatic hydrothermal fluid, basin fluid and their mixture. The tourmalines from granite are schorl with Fe/ (Fe+Mg) ratios of 0.912-1.00 and Na/(Na+Ca) ratios of 0.892-0.981. Tourmalines as an inclusion in quartz from the ore bodies are dravite with Fe/(Fe+Mg) ratios of 0.212-0.519 and Na/ (Na+Ca) ratios of 0.786-0.997. Tourmalines from the country rocks are dravite with Fe/(Fe+Mg) ratios of 0.313-0.337 and Na/(Na+Ca) ratio of 0.599-0.723. Tourmalines from cassiterite-tourmaline veins that occur in crannies within the country rocks show distinct optical zoning with alternate occurrence of dravite and schorl, Fe/(Fe+Mg)=0.374-0.843, Na/(Na+Ca)=0.538-0.987. It suggests that schorl in granite and dravite in carbonatite are related to magmatic fluid and basin fluid respectively. When magmatic fluid rose up and entered into crannies of the country rocks, consisting mainly of carbonatite, basin fluid would be constantly added to the magmatic fluid. The two types of fluid were mixed in structural crannies of the sedimentary basin accompanied with periodic geochemical oscillations to form material records in chemical composition zonings of tourmalines. | JIA Runxing FANG Weixuan HU Ruizhong | 2010 | Acta Geologica Sinica(English Edition)2010，84，1： | 8 |
| 8 | REE geochemical characteristics of the No. 302 uranium deposit in northern Guangdong, South China显示文摘The No. 302 uranium deposit, located in Guangdong Province, is a typical granite-type uranium ore deposit. REE geochemical characteristics of the wall rocks, pitchblende, altered rocks, calcite and fluorite from this deposit have been systematically studied in this paper. The result showed that the alkali-metasomatic granites and other altered rocks have the same REE distribution patterns as Indosinian granites. It is indicated that the hydrothermal ore-forming solution had altered the Indosinian granites, and ore-forming materials may directly originate from the Indosinian granites. Calcite and fluorite of different stages are the products derived from the same source but different stages. The evolution and degassing of the mineralizing solution might induce LREE enrichment to varying degree. Mantle fluid and a large volume of mineralizer may be the crucial factors controlling uranium mineralization, and the hydrothermal solution with mineralizer played an important role in U transport and concentration. Meanwhile, the degassing of CO2 might promote U and REE precipitation. | ZHANG Guoquan HU Ruizhong BI Xianwu FENG Haisheng SHANG Pengqiang TIAN Jianji | 2007 | Chinese Journal Of Geochemistry2007，26，4： | 8 |
| 9 | Diagenetic-metallogenic ages of pyritic cherts and their implications in Mojiang nickel-gold deposit in Yunnan Province,China显示文摘Diagenetic-metallogenic ages of pyritic cherts formed by the syn-sedimentation of hydrothermal vent and ages of the Jinchang Rock Formation in the Mojiang large nickel-gold deposit in the Ailaoshan gold metallogenic belt have been discussed on the basis of chronology of isotopic geochemistry. Nickel-gold-bearing pyritic cherts in the mining were formed by syn-sedimentation of hydrothermal vent in the Late Devonian, i.e. age by Sm-Nd isochronal method (t) = (358±8.6) (2σ) Ma and age by Rb-Sr isochronal method (t) = (354.7±0.72) (2σ) Ma. On the other hand, deep-water cherts from the Jinchang Rock Formation of the Upper Devonian in the area were initiated at the same time; that is, age by Sm-Nd isochronal method (t) = (359(+21) (2(7) Ma and age by Rb-Sr isochronal method (t) = (358.02±0.30) (2σ) Ma. | FANG Weixuan HU Ruizhong XIE Guiqing SU Wenchao QI Liang | 2001 | Chinese Science Bulletin2001，46，21： | 7 |
| 10 | U-Pb Zircon Age, Geochemical, and Sr-Nd-Pb Isotopic Constraints on the Age and Origin of Mafic Dykes from Eastern Shandong Province, Eastern China显示文摘U-Pb 锆石年龄, geochemical,和从东方山东省的 mafic 女同性恋的 Sr-Nd-Pb 同位素的数据,东方中国此处被报导。激光脱离诱导地联合了从调查 mafic 女同性恋的二件样品的 U-Pb 锆石分析产出一致年龄从 121.9 妈的血浆团 spectrometry (LA-ICP-MS )?????? 猠潨桳湯瑩捩吗? | LIU Shen HU Ruizhong FENG Caixia GAO Shan FENG Guangying LAI Shaocong QI Youqiang Ian M. COULSON YANG Yuhong YANG Chaogui TANG Liang | 2013 | Acta Geologica Sinica(English Edition)2013，87，4： | 7 |
| 11 | Characteristics of the mantle source region of sodium lamprophyres and petrogenetic tectonic setting in northeastern Hunan,China显示文摘A set of unique sodium lamprophyres is devel)0.1(oped in the Cenozoic intraconti)]nental extensional zone of northeastern Hunan. These lamprophyres are significantly different in major [(and trace elements and Sr, Nd isotopes from ordinary potassic lamprophyr\ es. )0(The rocks)0( )(are)( )]characterized as being enriched in Na2O and high in TiO2 and weakly enriched in Nb, Ta, Nd and LREE with no negative Eu anomaly. The trace elements and Sr, Nd isotopic compositions are typical of the mantle source region of oceanic island basalts (OIB). The average initial 87Sr/86Sr ratio is 0.705332, and the average initial 143Nd/144Nd ratio is 0.512650, with εNd(t) being[( )45.4(+3.5)(--)(+3.9, )]marking a mantle source region of unique sodium lamprophyres. The lamprophyres were formed by metasomatism of the primitive mantle at the bottom of lithosphere by vola[(tile)(-)(containing )68.2(f)(l)(u-)]ids/melts from the asthenosphere. The measured Rb-Sr isochron age of sodium lamprophyre is 136.61 Ma, representing a period in which the tectonic setting changed from compressive to extensional. [(Sodium lamprophyres were formed in a mantle plume tectonic set)0(ting characterized by mantle )]upwelling from the asthenosphere within the continent. Asthenospheric mantle upwelling is the principal geodynamic factor leading to the formation of sodium lamprophyres and constraining the [(Yanshanian i)0(n)(tracontinental extensional activity in northeast)0(ern Hunan, China.)] | JIA Dacheng HU Ruizhong LU Yan XIE Guiqing QIU Xuelin | 2004 | Science China Earth Sciences2004，47，6： | 7 |
| 12 | Mo isotopes in the Lower Cambrian formation of southern China and its implications on paleo-ocean environment显示文摘Over the past decade, as one of nontraditional stable isotopes, Mo isotope has developed rapidly and now become an important geochemical proxy to trace paleo-oceanic and atmospheric evolution through geological history. In this paper, Early Cambrian formations in southern China are investigated. The results indicate that δ 97/95Mo values of Early Cambrian seawater may have been larger than 1.4‰, values that are close to those of the modern ocean. It was also found that the variations in Mo isotope composition in samples from two sections (Huangjiawan and Gezhongwu in Guizhou) were closely related to changes in redox conditions during sedimentary processes. Combining our results with existing data, a preliminary model for the evolution of seawater Mo isotope composition through geological history was provided. It indicated that Mo isotopic variations were generally consistent with the evolution of atmospheric oxygen. | WEN HanJie ZHANG YuXu FAN HaiFeng HU RuiZhong | 2009 | Chinese Science Bulletin2009，54，24： | 6 |
| 13 | Sm-Nd isotopic geochronologyof the Yinachang Fe-Cu-REE deposit at Wuding,Yunnan Province and its genetic significance显示文摘Sm-Nd isotope systematics of ores and fluorites places precise time constraints on REE mineralization of the Yinachang Fe-Cu-REE deposit in Yunnan Province which occur in the Proterozoic Kunyan group. The ore-related fluorites contain high abundant REE, and show a strong enrichment of LREE and a positive Eu anomaly, which is in marked contrast to post-ore fluorites that are HREE en-riched. The Sm-Nd isochron ages of the ores and fluorites are 1539±40 Ma and 1617±100 Ma, respectively, and calculated εNd(t) are ?4.6 and ?3.2. Accurate age determinations of the mineralization demonstrate that the REE mineralization took place during early Mesoproterozoic. Together with other geological evidence from the ore deposit, the primary REE-bearing ore-forming fluids are suggested to have been derived from the Enriched Mantle, and the Yinachang Fe-Cu-REE ore deposit is of volcanic exhalation- hydro-thermal sedimentary origin. This study also imply that the sudden large-scale REE mineralization in the Mesoprotero-zoic epoch may have been induced by alkaline-rich anoro-genic magmatism which occurred at marginal rifts of the continent in the Mesoproterozoic. | YANG Yaomin TU Guanzhi HU Ruizhong SHI Xuefa | 2005 | Chinese Science Bulletin2005，50，18： | 6 |
| 14 | Paleoceanographic Indicators for Early Cambrian Black Shales from the Yangtze Platform, South China: Evidence from Biomarkers and Carbon Isotopes显示文摘The lower Cambrian Niutitang Formation, a widespread black shale deposition, is of geological interest because of its polymetallic beds, Cambrian explosion, depositional ages, dramatic environmental changes and so on. Previous study focused mainly on inorganic geochemistry and few studies have investigated the organic fractions of upper Neoproterozoic-lower Cambrian strata in South China. Here we report a study of biomarkers plus organic carbon isotopes for black shales from Ganziping, Hunan Province (China). All the saturated hydrocarbon fractions have a unimodal distribution of n-alkanes, a high content of short-chain alkanes and maximize at C 19 or C 20 (C 23 for sample Gzh00-1). The C 27 /C 29 sterane ratio ranges from 0.77 to 1.20 and 4-methylsteranes are in low abundance. These parameters indicate that algae and bacteria are the important primary producers. Furthermore, biomarker maturity proxies show the samples to be higher maturity. The low Pr/Ph values (<0.7) suggest that the samples were deposited under anoxic conditions and, likely, under stratified water columns. In addition, 25-norhopanes and gammacerane are present as diagnostic indicators of normal marine salinity and dysoxic to anoxic conditions. During the Early Tommotian, known to coincide with a transgression event, small shelly fossils increased in abundance and diversity. Moreover, positive δ 13 C org excursions close to 1.4‰ occur at the base of the Tommotian stage. In summary, the Early Cambrian black shales were deposited under dramatic paleoenvironmental changes, including oceanic anoxia, higher primary productivity and sea-level rise. | CHEN Lan ZHONG Hong HU Ruizhong XIAO Jiafei TSAI Louis Loung-Yie LIN Andrew Tien-Shun ZOU Yanrong | 2012 | Acta Geologica Sinica(English Edition)2012，86，5： | 6 |
| 15 | Geochemical Characteristics and Metallogenesis of the Qingkuangshan Ni-Cu-PGE Mineralized Mafic-Ultramafic Intrusion in Huili County, Sichuan Province, SW China显示文摘The Qingkuangshan Ni-Cu-PGE deposit, located in the Xiaoguanhe region of Huili County, Sichuan Province, is one of several Ni-Cu-PGE deposits in the Emeishan Large Igneous Province (ELIP). The ore-bearing intrusion is a mafic-ultramafic body. This paper reports major elements, trace elements and platinum-group elements in different types of rocks and sulfide-mineralized samples in the intrusion. These data are used to evaluate the source mantle characteristics, the degree of mantle partial melting, the composition of parental magma and the ore-forming processes. The results show that Qingkuangshan intrusion is part of the ELIP. The rocks have trace element ratios similar to the coeval Emeishan basalts. The primitive mantle-normalized patterns of Ni-Cu-PGE have positive slopes, and the ratios of Pd/Ir are lower than 22. The PGE compositions of sulfide ores and associated rocks are characterized by Ru depletion. The PGE contents in bulk sulfides are slightly depleted relative to Ni and Cu, which is similar to the Yangliuping Ni-Cu-PGE deposit. The composition of the parental magma for the intrusion is estimated to contain about 14.65 wt% MgO, 48.66 wt% SiO2 and 15.48 wt% FeOt, and the degree of mantle partial melting is estimated to be about 20%. In comparison with other typical Ni-Cu-PGE deposits in the ELIP, the Qingkuangshan Ni-Cu-PGE deposit has lower PGE contents than the Jinbaoshan PGE deposit, but has higher PGE contents than the Limahe and Baimazhai Ni-Cu deposit, and has similar PGE contents to the Yangliuping Ni-Cu-PGE deposit. The moderate PGE depletions in the bulk sulfide of the Qingkuanghan deposit suggest that the parental magma of the host intrusion may have undergone minor sulfide segregation at depth. The mixing calculations suggests that an average of 10% crustal contamination in the magma, which may have been the main cause of sulfide saturation in the magma. We propose that sulfide segregation from a moderately PGE depleted magma took place prior to magma emplacement at Qingkuangshan, that small amounts of immiscible sulfide droplets and olivine and chromite crystals were suspended in the ascending magma, and that the suspended materials settled down when the magma passed trough the Qingkuangshan conduit. The Qingkuangshan sulfide-bearing intrusion is interpreted to a feeder of Emeishan flood basalts in the region. | ZHU Feilin TAO Yan HU Ruizhong MA Yansheng | 2012 | Acta Geologica Sinica(English Edition)2012，86，3： | 5 |
| 16 | On emplacement ages of lam-proites in Zhenyuan County,Guizhou Province,China显示文摘Emplacement ages of lamproites that comprise lamproite and olivine lamproite in Zhenyuan County, Guizhou Province, China, have been constrained by the whole-rock Sm-Nd and Rb-Sr isochron methods and the whole rock K-Ar method. Intrusive activities of lamproites in the Sinantang area of Zhenyuan County, Guizhou Province, took place during the Late Cambrian, as indicated by the Sm-Nd isochron ages (t) = (503±17) (2σ) Ma and by the Rb-Sr isochron ages (t) = (501.2±4.6) (2σ) Ma. Intrusive activities of olivine lamproites at the Maping with Ⅱ -type diamond and Xitou in Zhenyuan County, Guizhou Province, took place from the Late Cambrian to the Early Ordovician, as evidenced by the Sm-Nd isochron ages (t) = (502±27) (2σ) Ma and by the Rb-Sr isochron age (t) = (502± 27) (2σ) Ma. This suggests that the upwelling hot materials derived from the deep mantle were emplaced from the Late Cambrian to the Early Ordovician (503-497 Ma), while the time terminal of cooling of the geothermal event of | Weixuan Fang Ruizhong Hu Wenchao Su Jiafei Xiao Liang Qi Guohao Jiang | 2002 | Chinese Science Bulletin2002，47，10： | 5 |
| 17 | Emplacement Ages and Geochemical Characteristics of Grabbroic Intrusions and Prospecting Orientation of Related Deposit in Luodian,Guizhou Province显示文摘炮兵阵地年龄, geochemical 特征和在 Luodian 县的 gabbroic 侵入上的大陆人动力学的分析,贵州省,基于同位素的年表(整个岩石的 Sm-Nd 和 Rb-Sr isochron 方法) 的研究被讨论了,主要元素,踪迹元素和 PGE。在学习区域的 gabbroic 侵入的恼人的活动发生在迟了的 Yanshanian Orogenic 运动(白垩纪时期) 期间,由 Sm-Nd isochron 年龄(t)= 显示了 99.6 # | FANG Weixuan HU Ruizhong SU Wenchao XIAO Jiafei | 2008 | Acta Geologica Sinica(English Edition)2008，82，4： | 5 |
| 18 | Ge-rich hydrothermal solutions and abnormal enrichment of Ge in coal显示文摘AT present, the main source of germanium includes two types of ore deposits: some sulfide-rich Pb, Zn,Cu, Ag and An deposits and some coal deposits. Germanium occurs as an associated element in these oredeposits. The Lincang germanium deposit discovered recently in China occurs in a basin where there areexposed the Neogene coal-bearing clastic rocks with Indosinian Ge-rich ((1.9-5.0)×10-6) granitesas the basement in Lincang County, Yunnan Province. Germanium is mainly concentrated in the coalseams of the first coal-bearing horizon (Nth2) and in regard to its grade (normally n×100×10-6 with themaximum over 1000×10-6) and scale (the proven reserve about 800 t), no such germanium mineralization has been reported so far in other parts of the world. What is the reason? The available studies have indicated that this germanium deposit is of epigenetic origin, whichdetermines that germanium must have been transferred into coal with the help of a kind of medium. It isnoticed that (i) organic germanium in natural waters is stable and it is never involved in its | HU Ruizhong, BI Xianwu, SU Wenchao, QI Huawen and YE Zaojun Intitue of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China | 1999 | Chinese Science Bulletin1999，44，S2： | 5 |
| 19 | Large selenium isotopic variations and its implication in the Yutangba Se deposit, Hubei Province, China显示文摘The selenium isotopic ratios have been measured in the Yutangba Se deposit, Hubei Province, China. The results show that the δ 82/76SeNIST values vary from -12.77‰ to 4.93‰, which is the largest Se iso- topic variation found so far in natural terrestrial samples. The sample Ytb-5 of high-selenium carbona-ceous shale has the lightest Se isotopic composition with a δ 82/76SeNIST value of -12.77‰. On the basis of variations of Se isotope in the deposit along with other geological and geochemical evidence, the 'redox model' is suggested to favor the explanation of the occurrence of native Se in the deposit. The application to the Yutangba Se deposit with the discovery of large Se isotopic fractionation for natural samples indicates the potential of Se isotope as a new geochemical tracer. | WEN HanJie Jean CARIGNAN HU RuiZhong FAN HaiFeng CHANG Bin YANG GuangShu | 2007 | Chinese Science Bulletin2007，52，17： | 5 |
| 20 | Zircon U-Pb Ages and Sr-Nd-Hf Isotopic Characteristics of the Huichizi Granitic Complex in the North Qinling Orogenic Belt and Their Geological Significance显示文摘The Huichizi granite complex is the largest Paleozoic I-type intrusion located in the North Qinling orogenic belt(NQB). In this study, we present systematic geochemical element data, zircon U-Pb ages, Lu-Hf isotopic data, and Sr-Nd isotopic data for the Huichizi granites. In terms of mineral and chemical compositions, these granites are biotite monzonitic and alkali-feldspar granites, both of which are characterized by high SiO 2 and total alkali contents and low Mg O, Ti O2, and TFeO contents. These granites are weakly peraluminous(A/CNK values are 1–1.06 for biotite monzonitic granites and 1.04–1.09 for alkali-feldspar granites) and possess the geochemical characteristics of adakitic rocks, e.g., high Sr contents(319 ppm–633 ppm), Sr/Y ratios(18.5–174), and(La/Yb)N ratios(17.6–57) and low MgO(0.04 wt.%–0.83 wt.%), Y(3.0 ppm–17.2 ppm), and heavy rare-earth element(HREE) contents. This indicates that these rocks were most likely derived from the partial melting of a thickened lower crust. In situ zircon U-Pb dating of these granites yields Early Caledonian ages(437 Ma for biotite monzonitic granites and 424 Ma for alkali-feldspar granites), indicating that the Huichizi granitic complex is the product of multi-periodic magmatism. The positive but varying zircon εHf(t) values(+0.6 to +8.5) suggest that this thickened lower crust was mainly juvenile, i.e., accreted from depleted mantle during the Neo-Mesoproterozoic Period, but involved the ancient recycled crust. Biotite monzonitic granites formed during crust thickening at the extrusion stage, whereas the alkali granites formed during crust thickening at the extension stage(post extrusion). The Huichizi granite complex witnessed the process of extrusion to extension because of the collision between the NCB and the Qinling microcontinent in the Caledonian. | Youwei Chen Ruizhong Hu Xianwu Bi Shaohua Dong Yue Xu Ting Zhou | 2018 | Journal of Earth Science2018，29，3： | 5 |
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