The Jinshajiang-Ailaoshan suture zone in southwestern China preserves the magmatic record of the late Permian Paleo-Tethyan oceanic subduction system and the Emeishan mantle plume. However, little is known about whether direct plume-subduction interaction occurred in southwestern China during the late Permian. Here we report a study of late Permian (ca. 254 Ma) quartz monzonites and granites in the locality of Ma' andi in the Jinping area in the southern part of the Ailaoshan suture zone. The quartz monzonites and granites have medium-high SiO2 (62.1-74.9 wt%), high Na2O + K2O (7.8-9.7 wt%), and low TiO2 (0.24-0.84 wt%) and CaO (0.18-4.1 wt%) contents. The studied rocks are enriched in Rb, Th, U, and light rare earth elements and depleted in Ba, Sr, Eu, and Ti. They exhibit A-type granite mineral assemblages and geochemical characteristics, including the occurrence of anhedral amphibole and biotite interstitial to quartz and feldspar, high 10,000 x Ga/Al (1.8-5.1, mean = 2.9) and FeOT/MgO (3.8-23.7) ratios, and high Zr + Nb + Ce + Y contents (345-1024 ppm, mean = 613 ppm). The quartz monzonites and granites have slightly enriched to depleted whole-rock Nd compositions (epsilon(Nd)(t) = -0.9 to +1.3; T-DM = 1.2 to 0.8 Ga) and depleted zircon Hf isotopic compositions (epsilon(Hf)(t) = +3.6 to +9.2; T-DM = 0.8 to 0.5 Ga) that are similar to those of Emeishan OIB-type high-Ti basalts. The studied rocks also slow ((206)pb/Pb-204)(i) ratios of 17.206-18.304, (Pb-207/Pb-204)(i) ratios of 15.515-15.571, and ((208)pb/Pb-204)(i) ratios of 36.404-38.294, respectively, which can best be explained by a mixture of dominant enriched-mantle and subordinate depleted-mantle materials. Combining regional geological data with geochemical characteristics, we suggest that the primary mafic magmas of the quartz monzonites and granites were formed mainly by partial melting of a hybridized source consisting of dominant Emeishan-fossil-plume material (85%-90%) and subordinate (10%-15%) recycled Paleo-Tethyan oceanic crust. Subsequently, these mafic magmas underwent sequential fractional crystallization, forming the A-type quartz monzonites and granites. Plume-slab interaction has been only rarely identified in pre-Cenozoic systems, which casts doubt on the importance of plume-slab interaction through the geological record. However, our study provides direct magmatic evidence for pre-Cenozoic plume-slab interaction.

以"Web of Science核心合集"的2759篇文献为数据源,应用科学计量工具CiteSpace绘制了中国基性岩研究的知识图谱,对该研究领域的发文特征、研究力量、知识基础、研究热点、趋势等进行了可视化分析.研究发现,中国基性岩研究可以概括为岩石类型、大地构造环境和研究区域特征三类方向,目前研究的热点包括:华北克拉通(North China Craton)、 大火成岩省(large igneous province)、 大陆地壳(continental crust)、中亚造山带(Central Asian Orogenic Belt)、 构造演化(tectonic evolution)、 岩石成因(petrogenesis)等,并且中国的研究机构已经形成了数个国际上成果突出的作者群,在该研究领域的发文量和影响力都处于领先,但是国际合作还需进一步加强.

对靖西地区出露的晚古生代基性-超基性岩进行了全岩主量、微量元素等地球化学研究,结果表明:基性岩主要为辉绿岩,超基性岩则为苦橄岩;基性岩具有较低的SiO 2 （51.34%～53.17%）和较高的MgO（4.67%～6.12%）含量,（K 2 O+Na 2 O）在5.03%～8.06%,具有典型碱性玄武岩特征;超基性岩则具有更低的SiO 2 （39.76%）和极高的MgO（23.97%）,二者均落入碱性玄武岩系列。基性-超基性岩∑REE在（45.47～128.95）×10 -6 ,（La/Yb） N 值在6.67～10.75,δEu值为0.96～1.08,稀土特征总体显示为轻稀土相对富集,重稀土相对亏损的右倾型式,具有与OIB相似的配分趋势,指示源区相对富集;基性-超基性岩不相容元素含量整体偏低,略亏损高场强元素（HREE、 Nb、 Ti等）,指示源区部分熔融程度较低。结合前人研究及岩石沉积背景特征,认为靖西基性-超基性岩为右江盆地早期演化的产物,形成于局部拉张的构造环境,与裂谷作用相关,推测该区域晚古生代受金沙江-哀牢山特提斯洋的打开和演化的影响,右江盆地局部拉张裂解,一系列深大断裂沿北西向展开,早期在局部形成与裂谷作用相关的岩浆活动。晚古生代后期右江盆地可能已演变为弧后盆地属性。

华南西南缘凭祥地区位于特提斯构造域东端，华南与印支陆块碰撞缝合带的北部，该区出露的三叠纪中酸性火山岩是古特提斯洋俯冲过程中在华南陆块边缘形成的大陆弧产物，这些火山岩同时携带的大量来自华南陆块基底的捕获锆石为华南陆块的构造热事件研究将提供重要的信息。对凭祥地区三叠系北泗组英安岩进行了同位素年代学、地球化学及锆石Hf同位素研究，获得了一个英安岩样品的加权平均年龄为（227.8±1）Ma，这些英安岩具有高SiO2、K2O含量，极低的MgO、MnO和CaO含量，富集大离子亲石元素（Rb、Ba、Th和U）和亏损高场强元素（Nb、Ta）的特点，显示了典型的岛弧岩浆作用特征，代表古特提斯洋向北俯冲至华南陆块之下形成的大陆弧产物。其余两个英安岩样品中的70粒锆石主要为来自华南陆块基底的捕获锆石，其年龄数据变化区间较大，为1010~231 Ma，这些捕获锆石U-Pb年龄频谱分布主要集中在四个区间：11010~800 Ma（峰值900 Ma），其锆石的eHf（t）值为4.5~15.1，响应扬子和华夏陆块之间聚合-裂解-再聚合的构造演化事件，反应了其幔源岩浆的广泛参与；2720~620 Ma（峰值680 Ma）响应南华纪已拼合的扬子-华夏陆块的再次发生裂解；3490~400 Ma（峰值450 Ma），其锆石的eHf（t）值为2.2~-7.8，响应华南早古生代加里东运动有关的壳-幔相互作用岩浆事件；4280~230 Ma（峰值250 Ma），其锆石eHf（t）值为-13.6~-16.5，地壳模式年龄为2.3~2.1 Ga，代表了印支与华南陆块之间古特提斯洋俯冲闭合的岩浆事件。文章的研究结果揭示了凭祥北泗组英安岩与华南陆块的亲缘性，其结晶年龄限定了华南与印支陆块之间的古特提斯洋俯冲结束、陆-陆开始碰撞的最晚时限为中-晚三叠纪。

桂西地区龙川等地出露层状-似层状基性岩,对其岩石学及地球化学研究表明,该区辉绿岩属于碱性玄武岩系列,岩石SiO 2 含量为45.56%～46.76%, TiO 2 为2.83%～3.60%, Na 2 O+K 2 O为3.52%～4.28%,δ值为3.31～7.17;∑REE为（159.28～248.54）×10 -6 ,δEu=1.01～1.32。Ti/Y值为538～1 067,属于峨眉山高Ti玄武岩系列,与二叠纪ELIP内带高Ti玄武岩和桂西其他地区基性岩具有相似的地球化学特征。从Dy/Dy * -Dy/Yb和Ti/Y值协变关系中判别,龙川基性岩和峨眉山高Ti玄武岩具有同源性,与峨眉山高Ti玄武岩和桂西其他地区高Ti基性岩相比,表现出了更低Dy/Dy * 值特征,揭示了其熔体来源于更深部且熔融程度更低的岩浆源区,说明龙川极高Ti/Y基性岩代表了ELIP的地幔柱岩浆作用在外部带延伸的结果,是峨眉山地幔柱高Ti岩浆源区更低程度熔融的岩浆产物。

广西岑溪地区出露众多花岗岩体,形成了大量离子吸附型稀土矿床,前人研究结果表明其与粘土矿物有关.为了真正了解粘土矿物对这种类型稀土矿床成因的影响,用X射线衍射方法,对广西岑溪和村稀土矿床的粘土矿物组成进行研究,分析表明粘土矿物主要是高岭石,其次是伊利石和蒙脱石,同时,粘土矿物的含量和稀土品位高低具有一定的相关性.这类稀土矿床的成因机制是含矿岩体经过风化作用后以离子形式溶于水中的稀土元素被粘土矿物吸附并在风化层底部富集而成矿.

Reference materials are used in monitoring the accuracy,reproducibility and stability of the experimental data in in situ microanalysis. Homogeneity is important for reference materials. The MPI-DING glass was analyzed by an Electron Probe Micro Analyzer to discuss the homogeneity and stability of the synthetic glass. The results of major elements were compared with preferred value of other international laboratories and the deviation is basically within the range of 10％,meanwhile the RSD is mostly less than 5％. The results show that the data quality obtained from the electronic probe laboratory of Guilin University of Technology has reached the scientific research requirements. The electron probe was used to determine the major elements from the mid-oceanic ridges and volcanic glass of the eastern Pacific Ocean. The measurement results show that the homogeneity as SD is lower than 1. Compared with the data between the natural glass and the artificial glass,the content of elements in synthetic glass at different positions shows an even distribution. However,for the nature glass,elements in different locations are not absolutely homogeneous,and far below the standard homogeneity requirements. Different elements show different degree of homogeneity in different glass. Ca,K,Ti and Fe show more uniform distribution behavior in both acid and basic rocks.

The layered intruded mafic lavas and dikes are well cropped out around the Longlin-Xilin area in western Guangxi.The petrogenesis study of the mafic dikes will better understand the tectonic-magmatic significance of this region.Petrographic and major trace element geochemical data show that the mafic dikes belong to alkaline basalt with low SiO2and high TiO2,MgO,LREE-enriched characteristics,with Ti/Y =579-742,(La/Yb) N =6.70--10.20,Nb/U =23-33 and Nb/La =0.80-0.94.Thus,the geochemical features of dikes akin to the Emeishan large igneous province(ELIP) high-Ti basalts,but they possess the slightly depleted Zr,Hf and Y,and indicate such a melt from the partial melting plume mantle source when experiencing the weak crustal contamination.The low (87Sr/86Sr)t(from 0.705 023 to 0.705 782) and high eNd(from +0.7 to + 1.0),akin to ELIP high-Ti basalts and other high-Ti mafic rocks of western Guangxi,suggest that the Longlin-Xilin mafic dikes most likely represent a part of outer zone of the ELIP plume magmatism.From the regional tectonic relationships between the mafic dikes and the fine-disseminated gold deposits as well as the extensive evolved carbonate platform uplifting,we further conclude that the ore-forming process of gold deposit resembles to that of Nevada's Carlin-type gold deposit in US,the interaction between the Emeishan plume and Paleotethyan subduction zone induced the regional gold deposits.

Late Permian mafic flows and dikes are prominent features in and around the Western Guangxi region in southern China. Based on petrographic, geochemical and Sr-Nd isotopic data, the western Guangxi mafic rocks are geochemically akin to the Emeishan large igneous province (ELIP) high-Ti basalts, except that they possess extremely elevated Ti/Y ratios (750-2000). The Dy/Yb and Ti/Y vs. Dy/Dy* covariations of the mafic rocks indicate a garnet-controlled magmatic differentiation of a mafic melt at relatively great depth. The limited epsilon(Nd)(t) range from +0.41 to +1.81 also suggests minimal crustal contamination of such a melt. Geochemical modeling using TiO2/Yb vs. Nb/Yb and Zr/Y vs. Nb/Y projections indicate that the parental melts of the western Guangxi mafic rocks formed at a low degree (<5%) of partial melting at or over 3.5 GPa, consistent with a deep mantle plume source under a thick continental lithosphere. Thus, the Guangxi extremely high Ti/Y mafic rocks most likely represent a part of outer zone of the ELIP plume magmatism. Results of this study reinforce the previously proposed temporal and spatial distribution of the ELIP. (C) 2016 Elsevier Ltd. All rights reserved.

The Napo area in the western Guangxi province, South China, is located in the southwestern margin of the South China Block, and to the north of the North Vietnam Block. The Upper Permian mafic rocks well crop out in the west-southwest of Napo County, and are composed of layered, sub-volcanic diabases and orbiculite. Geochemically, the Napo mafic rocks can be subdivided into two groups: high-Ti group (TiO2>2.8%, Ti/Y>500) and low-Ti group. The high-Ti group is mainly composed of alkaline basalts, and the low-Ti group of tholeiite. The high-Ti rocks have lower SiO2, MgO, higher FeOt, P2O5 than the low-Ti ones. The high-Ti group shows an enrichment of LILE, HFSE, and significant fractionation between LREE and HREE, akin to ocean island basalts (OIB), suggestive of an affinity with the Emeishan high-Ti basalts. In contrast, the low-Ti rocks display relatively higher SiO2, MgO, lower FeOt, P2O5, enriched LILE, depleted Nb, Ta, and relatively flat REE patterns, indicative of island-arc geochemical signatures. The trace element ratios and the tectonic discrimination diagrams indicate that the Napo high-Ti mafic rocks were most likely derived from the enriched OIB mantle source, while the low-Ti group showed the transitional features from OIB- to island arc-like signatures. Integrating the geochemistry and regional geological background, we suggest that the Napo high-Ti mafic rocks were probably related to the Emeishan mantle plume magmatism; however, the low-Ti mafic rocks were possibly produced by interaction between the subducting Paleotethyan slab and the Emeishan mantle plume.

The mid-ocean ridge volcanic glass is of mantle partial melting carrying lots of information on formation of oceanic crust and its magmatism. The major element geochemical characteristics of mid-ocean ridge glass from Pacific mid-ocean ridge system is studied,and the element distribution characters of magma is discussed in this paper. Results indicate that the major element composition of glass displays normal evolution,with Si O_2 increasing,the Na_2 O increasing from 2% to 6%,K_2 O increasing from 1% to 5%,but Ca O decreasing from10%- 13% to 1%,Fe O decreasing from 9%- 13% to 3%,and Al_2O_3 decreasing from 18% to 13% when Si O_2 increasing. The distribution pattern of major elements suggests the heterogeneity of magma,which was likely caused by mantle heterogeneity. Moreover,the glass from same mid-ocean ridge system also shows the composition heterogeneity,which is probably due to the locality geodynamic difference( es) inducing from major element heterogeneous distribution.

本文选取桂西基性岩为研究对象.对桂西地区基性岩岩浆的分布、构造、成因机制、成矿背景的研究综述进行了分析,通过地球化学特征的对比分析,证明了桂西基性岩岩浆与峨眉山大火成岩之间存在一定的联系.

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 298-299 Meeting Abstracts The Geochemistry of Mafic Intrusives at Guixi Gold Deposits, SW China Xijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorGuo Lin, Guo Lin Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorWenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author Xijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorGuo Lin, Guo Lin Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorWenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12371_12Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 298-299 RelatedInformation

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 291-292 Meeting Abstracts Permian Mafic Magmatism and Related Gold Mineralization in the Bama District, SW China: A Result of Mantle Plume Activity Wenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorXijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorLin GUO, Lin GUO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author Wenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorXijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorLin GUO, Lin GUO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12371_8Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 291-292 RelatedInformation

The South China tectonic block (SCB) is bounded to the north by the Qinling-Dabie orogenic belt, and to the west and southwest by the Tibetan and Indochina blocks. The Permian mafic rocks (e.g. diabase and basalt) are concentrated in the Shijia of western Guangxi, economically significant gold mineralizations are genetically associated with these mafic rocks (Fig.1). However, the causes of magmatism and related gold deposit background are controversial. Here, we present the comprehensive major element, trace element data of orebearing mafic rocks with previous published data, detailed discuss the geochemical characteristics of the bulk of Shijia mafic rocks and their petrogenesis.

Acta Geologica Sinica - English EditionVolume 88, Issue s2 p. 697-699 Meeting Abstracts The Gold Mineralization Background of Napo Permian Mafic Magmatism in Western Guangxi Province: Evidence for Emeishan Mantle Plume and Paleotethyan Subduction Interaction Xuefeng CHEN, Xuefeng CHEN Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorXijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorLin GUO, Lin GUO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorWenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author Xuefeng CHEN, Xuefeng CHEN Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorXijun LIU, Corresponding Author Xijun LIU Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaCorresponding author. E-mail: xijunliu@gmail.comSearch for more papers by this authorLin GUO, Lin GUO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorYu SHI, Yu SHI Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorWenlong HUANG, Wenlong HUANG Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this authorShuai LIAO, Shuai LIAO Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin University of Technology, Guilin, 541004 ChinaSearch for more papers by this author First published: 29 December 2014 https://doi.org/10.1111/1755-6724.12375_10Citations: 1Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume88, Issues2Special Issue: Meeting Abstracts: The 14th Quadrennial International Association on the Genesis of Ore Deposits Symposium. August 19–22, 2014, Kunming, ChinaDecember 2014Pages 697-699 RelatedInformation

A method for getting high quality Pb isotope ratio analysis using Pb-207-Pb-204 double spike method has been developed at Scripps Institution of Oceanography (SIO), which corrected the mass fractionation effects during small amount Pb loading isotopic analysis by thermal ionization mass spectrometry (TIMS), with the minimum amount of 8x10(-9)g Pb per load. The double spike method effectively improves in both precision and accuracy without recourse to excessively rigorous loading or run conditions. Over a period of fifteen months accuracy double spike tested for Pb standard SRM981 in SIO isotope laboratory, an external precision of +/- 0.0038, +/- 0.0040, +/- 0.0122 (2 sigma, n=53) was obtained for Pb-206/Pb-204, Pb-207/Pb-204 and Pb-208/Pb-204 rations, although the small amount Pb loading, which present a same excellent accuracy and external precision as other laboratories reported. Therefore, this method is superior to precise and accurate isotope analyses of low level Pb concentration geological and environmental samples, and will be a highly powerful tool in the future of earth sciences and environmental sciences.