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内蒙古白云鄂博铁-铌-稀土矿床矿化蚀变矿物组合及流体组成

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现代地质 2024年第1期38卷 13-24页

作者：李厚民李立兴李以科柯昌辉李瑞萍李小赛王亿自然资源部成矿作用与资源评价重点实验室中国地质科学院矿产资源研究所北京100037

针对内蒙古白云鄂博铁-铌-稀土矿床是否多期成矿及底板白云岩的成因争论,本文通过光薄片岩矿鉴定和扫描电子显微镜研究,获得如下信息:(1)碳酸岩脉、磁铁矿石、蚀变岩及矿化白云岩中矿化蚀变的矿物组成类似,均以磁铁矿(碳酸岩脉中除外)... 详细信息

针对内蒙古白云鄂博铁-铌-稀土矿床是否多期成矿及底板白云岩的成因争论,本文通过光薄片岩矿鉴定和扫描电子显微镜研究,获得如下信息:(1)碳酸岩脉、磁铁矿石、蚀变岩及矿化白云岩中矿化蚀变的矿物组成类似,均以磁铁矿(碳酸岩脉中除外)、独居石、氟碳酸稀土矿物(氟碳铈矿等)、方解石、萤石、磷灰石、富钡矿物(重晶石或毒重石)、黑云母、富钠矿物(钠闪石、霓石)等为主,常见硫化物,显示为同一种富含Fe、REE、Ca、Ba、K、Na、Si及挥发分CO_(2)、P_(2)O_(5)、F、S的流体,岩(矿)石的结构构造也显示出明显的一期成矿特点,支持白云鄂博矿床主体是一期成矿事件的产物。(2)稀土矿化与底板白云岩不是同一流体的产物,稀土矿化与方解石为主的碳酸岩脉有关,有可能为火成碳酸岩或浆液过渡态流体;底板白云岩是稀土矿化的围岩,有更多的沉积成因信息,可能为热水沉积岩,或者为热液改造的沉积碳酸盐岩。(3)磁铁矿化与稀土矿化是同一成矿事件的产物,但碳酸岩中缺乏磁铁矿表明,铁质来源与稀土来源是否相同仍需要进一步研究。

关键词：磁铁矿稀土矿物组成流体成分白云鄂博内蒙古

独居石Th-Pb年代学揭示白云鄂博富稀土碳酸岩侵位和热液交代历史

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地球科学 2024年第8期49卷 2685-2696页

作者：訾建威李立兴李以科 Birger Rasmussen 柯昌辉中国地质大学地质过程与矿产资源国家重点实验室武汉430078 中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室北京100037 西澳大学地球科学学院 PerthWA 6009Australia 科廷大学约翰·德莱特研究中心 BentleyWA 6102Australia

越来越多的证据表明,白云鄂博超大型稀土矿床与区内分布的火成碳酸岩有密切的成因联系,因此精确约束碳酸岩的侵位时代对研究成矿历史和机制非常关键.然而,由于后期复杂的热液叠加影响,以往的年代学研究结果大多得到后期扰动事件的年龄,... 详细信息

越来越多的证据表明,白云鄂博超大型稀土矿床与区内分布的火成碳酸岩有密切的成因联系,因此精确约束碳酸岩的侵位时代对研究成矿历史和机制非常关键.然而,由于后期复杂的热液叠加影响,以往的年代学研究结果大多得到后期扰动事件的年龄,而对碳酸岩岩浆活动的启动时间的制约则比较缺乏.为重建白云鄂博碳酸岩型稀土矿的岩浆—热液成矿历史,我们利用SHRIMP离子探针对一号碳酸岩墙(吴氏岩墙)及其蚀变围岩样品开展了薄片原位独居石Th-Pb年代学研究.碳酸岩中最老的独居石记录了其侵入时代1401±39 Ma (MSWD=0.57,n=7),这是首次从白云鄂博的独居石得到碳酸岩初始岩浆年龄,证实白云鄂博碳酸岩可能代表了华北克拉通从Nuna超大陆裂解过程中早期岩浆作用产物.同时,碳酸岩和霓长岩化围岩中的独居石还获得了格林威尔期到加里东期的一系列年龄数据,反映了后期构造热事件的叠加—扰动记录.尤其是,本研究识别出泛非期构造事件的独居石年代学记录(529±17 Ma,MSWD=1.01,n=6)并对其地质意义进行了初步探讨.本文的研究结果和认识为理解白云鄂博碳酸岩型稀土矿的岩浆-热液历史及成矿构造动力学背景提供了新的关键证据,所采用的研究方法对解决类似碳酸岩和稀土矿的年代学问题具有启示意义.

关键词：白云鄂博稀土矿一号岩墙(吴氏岩墙) 火成碳酸岩独居石 Th-Pb年代学地球化学

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冀北招兵沟铁磷矿床成矿时代及成因研究

现代地质 2024年第1期38卷 46-55页

作者：王亿李立兴李厚民李小赛马兰晶邢玉亮孙欣宇戴阳王小慧自然资源部成矿作用与资源评价重点实验室中国地质科学院矿产资源研究所北京100037 河北省地质矿产勘查开发局第五地质大队河北唐山063002 中国地质大学(北京)地球科学与资源学院北京100083

为探讨冀北—辽西地区太古宙变质岩系中铁磷矿床的成因问题,本研究选取招兵沟矿床开展了岩相学、年代学和地球化学研究。野外观察表明,前人描述的条带状铁磷矿石实际上大多为含铁磷矿脉的黑云角闪斜长片麻岩,可见铁磷矿脉切穿片麻理。... 详细信息

为探讨冀北—辽西地区太古宙变质岩系中铁磷矿床的成因问题,本研究选取招兵沟矿床开展了岩相学、年代学和地球化学研究。野外观察表明,前人描述的条带状铁磷矿石实际上大多为含铁磷矿脉的黑云角闪斜长片麻岩,可见铁磷矿脉切穿片麻理。含铁磷黑云角闪斜长片麻岩中的锆石与矿石矿物铁钛氧化物和磷灰石密切共生。阴极发光图像上显示基性岩浆锆石特征,无/弱环带或斑块状结构,LA-ICP-MS U-Pb定年获得^(206)Pb/^(238)U加权平均年龄为(282±3)Ma(MSWD=0.78),指示铁磷矿化时代为早二叠世,而非传统认为的新太古代。招兵沟含铁磷黑云角闪斜长片麻岩与区域辉石-角闪石岩侵入体形成时代接近,微量元素地球化学特征相似度高,说明成矿母岩为辉石-角闪石岩。招兵沟铁磷成矿与冀北地区沿红石砬—大庙断裂带发育的显生宙阿拉斯加型镁铁-超镁铁质岩浆活动密切相关。综合来看,招兵沟铁磷矿床可能是与基性岩浆活动有关的矿床,而非传统认为的变质型矿床,其他相似矿床的成因也需要进一步研究。

关键词：铁磷矿床成矿年龄矿床成因阿拉斯加型岩体华北克拉通

湘南科学深钻构造样式及其对区域成矿预测的启示

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矿床地质 2024年第3期43卷 688-706页

作者：刘阳生赵正文一卓许若潮李立兴李厚民许以明田军委湖南省矿产资源调查所湖南长沙410014 中国地质科学院矿产资源研究所北京100037 成都理工大学地球科学学院四川成都610000

湘南科学深钻位于钦杭结合带中段桂阳县宝山矿区,终孔孔深3008.93 m。文章在岩芯地质-地球化学精细编录、测井等工作基础上,建立了岩性、构造、矿化蚀变、地球化学、岩石物性等精细剖面。科学深钻揭露构造行迹自上至下可分为3个构造层:... 详细信息

湘南科学深钻位于钦杭结合带中段桂阳县宝山矿区,终孔孔深3008.93 m。文章在岩芯地质-地球化学精细编录、测井等工作基础上,建立了岩性、构造、矿化蚀变、地球化学、岩石物性等精细剖面。科学深钻揭露构造行迹自上至下可分为3个构造层:①上部(韧)脆性构造层,构造样式以脆性断裂为主,层间滑动为次,间夹塑性变形;②中部脆韧性构造层,构造样式主要为顺层曲面劈理;③下部韧性构造层,构造样式以塑性变形为主,层间滑动为次,具塑性剪切特征。结合区域深部构造特征研究显示,该区处于北东向炎陵-郴州-临武深断裂带中,燕山期强烈活动诱发岩浆上侵至深断裂的上盘(深断裂北西侧),形成宝山-大坊花岗闪长斑岩脉带及其相关的铜铅锌银金矿、黄沙坪石英斑岩岩枝群及其相关的铅锌银矿、黄沙坪花岗斑岩岩枝群及其相关的钨锡钼铅锌矿。矿石硫化物δ^(34)S同位素研究表明,矽卡岩型铜铅锌矿中的硫来源于岩浆,脉状铅锌银金矿除岩浆热液硫外,有地层硫的加入。综合深部构造-岩浆岩特征及地球物理信息,文章提出:宝山中区-1350 m以深矽卡岩型铜矿找矿靶区、宝山至大坊之间的米筛井一带北东向脉状铅锌银金找矿靶区、黄沙寺矿区深部可能存在隐伏的花岗闪长斑岩及花岗斑岩,是寻找钨锡钼铋铜铅锌矿的找矿靶区。

关键词：湘南科学深钻构造样式找矿靶区钦杭结合带

维普期刊数据库博看期刊

Iron Isotopes and Trace Element Compositions of Magnetite from the Submarine Volcanic-Hosted Iron Deposits in East Tianshan,NW China:New Insights into the Mineralization Processes

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Journal of Earth Science 2021年第1期32卷 219-234页

作者： Zhe Song Houmin li lixing li Jianhua Ding Jie Meng State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Development and Research Center of China Geological Survey Beijing 100037China

The Aqishan-Yamansu metallogenic belt(AYMB)in East Tianshan hosts abundant sub-marine volcanic-hosted iron *** there is agreement with the magmatic source of the ore-forming materials and the role of hydrothermal replacement in iron ore formation,the mineraliza-tion processes of these iron deposits remain *** ore types are identified on the basis of the geological occurrences of minerals and the sequence of mineral in *** typeⅠores are characte-rized by magnetite,diopside,amphibole with a few pyrite,and *** type II ores are mainly composed of magnetite,garnet,chlorite with a few pyrite,while the type III ores are mainly composed of magnetite,quartz,calcite with a few *** order to constrain the mineralization processes of these ore types,we performed iron isotopes and trace element compositions of magnetite from three typical iron deposits(Yamansu,Duotoushan and Luotuofeng).Trace element and Fe isotope investiga-tions of the three ore types reveal two major *** groupⅠconsists of analyses of the typeⅠandⅡores,with both showing a narrow range of positiveδ56Fe values(+0.08‰to+0.22‰for typeⅠores and+0.15‰ to+0.22‰ for typeⅡores)and plotting in the range of the ortho-magmatic *** contrast,the group 2 is composed merely of the typeⅢores,showing a wider range of negativeδ56Fe values(-0.49‰ to-0.01‰),which is similar to the features of Fe-skarn *** shown in the binary dia-grams of magnetite trace elements and a fractionation of the Fe isotopes,different ore types were likely produced during gradually changing ore-forming stages from magmatic to ***,the submarine volcanic-hosted iron deposits in the East Tianshan are likely the results of a continuous magmatic-hydrothermal mineralization process.

关键词： East Tianshan submarine volcanic rock-hosted iron deposit Fe-isotopes magnetite trace elements magmatic-hydrothermal

基于改进TFDR法的核电站仪控电缆断裂缺陷检测

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电力工程技术 2024年第4期43卷 177-185页

作者：邓红雷李力行涂画姚力恺张翔刘刚华南理工大学(广东省绿色能源技术重点实验室) 广东广州510640 苏州热工研究院有限公司江苏苏州215004

时频域反射(time-frequency domain reflectometry,TFDR)法具有成熟便捷、分辨率较高的特点,广泛应用于各类电缆的故障测距。为了有效判别和精确定位核电站仪控电缆绝缘屏蔽层断裂缺陷,文中通过介入热应力,提出一种改进TFDR法。对50 m... 详细信息

时频域反射(time-frequency domain reflectometry,TFDR)法具有成熟便捷、分辨率较高的特点,广泛应用于各类电缆的故障测距。为了有效判别和精确定位核电站仪控电缆绝缘屏蔽层断裂缺陷,文中通过介入热应力,提出一种改进TFDR法。对50 m多芯仪控电缆进行不同程度的断裂破损模拟,并使用传统TFDR法和改进TFDR法进行检测实验验证。检测结果显示,改进TFDR法对弱断裂缺陷的定位峰峰值为0.2,是传统TFDR法的2.5倍,且不同程度断裂缺陷下定位误差率均小于2.5%。可得出如下结论:相较于传统TFDR法,改进TFDR法使用热应力浮动方差曲线作为缺陷判别的依据,可显著提高对弱断裂缺陷的判别能力;改进TDFR法通过对原定位距离进行修正,进一步提高了对弱断裂破损的定位精准度,可实现对微弱缺陷的有效识别定位。

关键词：仪控电缆缺陷定位时频域反射(TFDR)法时频互相关热应力浮动方差

Petrological and Geochemical Constraints on the Protoliths of Serpentine-Magnetite Ores in the Zhaoanzhuang Iron Deposit,Southern North China Craton

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 627-665页

作者： MENG Jie li Houmin li lixing SANTOSH M SONG Zhe YANG Xiuqing MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China Department of Earth Sciences University of Adelaide SA 5005 Australia Faulty of Earth Resources China University of Geosciences Wuhan 430074 China Chang'an University Xi'an 710064 China

The uncommon Mg-rich and Ti-poor Zhaoanzhuang serpentine-magnetite ores within Taihua Group of the North China Craton （NCC） remain unclear whether the protolith was sourced from ultramafic rocks or chemical sedimentary sequences. Here we present integrated petrographic and geochemical studies to characterize the protoliths and to gain insights on the ore-forming processes. Iron ores mainly contain low-Ti magnetite （TiO2 -0.1wt%） and serpentine （Mg#=92.42-96.55）, as well as residual olivine （Fo=89-90）, orthopyroxene （En=89-90） and hornblende. Magnetite in the iron ores shows lower AI, Sc, Ti, Cr, Zn relative to that from ultramafic Fe-Ti-V iron ores, but similar to that from metamorphic chemical sedimentary iron deposit. In addition, interstitial minerals of dolomite, calcite, apatite and anhydrite are intergrown with magnetite and serpentine, revealing they were metamorphic, but not magmatic or late hydrothermal minerals. Wall rocks principally contain magnesian silicates of olivine （Fo=83-87）, orthopyroxene （En=82-86）, humite （Mg#=82-84） and hornblende [XMg=0.87--0.96]. Dolomite, apatite and anhydrite together with minor magnetite, thorianite （Th-rich oxide） and monazite （LREE-rich phosphate） are often seen as relicts or inclusions within magnesian silicates in the wall rocks, revealing that they were primary or earlier metamorphic minerals than magnesian silicates. And olivine exists as subhedral interstitial texture between hornblende, which shows later formation of olivine than hornblende and does not conform with sequence of magmatic crystallization. All these mineralogical features thus bias towards their metamorphic, rather than magmatic origin. The dominant chemical components of the iron ores are SiO2 （4.77-25.23wt%）, Fe203T （32.9-80.39wt%） and MgO （5.72- 27.17wt%） and uniformly, those of the wall rocks are also SiO2 （16.34-48.72wt%）, MgO （16.71- 33.97wt%） and Fe203T （6.98-30.92wt%）. The striking high Fe-Mg-Si contents reveal that protolith of the Zhaoanzhu

关键词： protolith serpentine-magnetite ores Fe-Mg-Si-rich rocks Zhaoanzhuang North China Craton

Occurrence of the Iron–rich Melt in the Heijianshan Iron Deposit, Eastern Tianshan, NW China: Insights into the Origin of Volcanic Rock–hosted Iron Deposits

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Acta Geologica Sinica(English Edition) 2018年第2期92卷 666-681页

作者： li Houmin li lixing DING Jianhua li Yanhe SONG Zhe MENG Jie MA Yubo MLR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences

Long-standing controversy persists over the presence and role of iron-rich melts in the formation of volcanic rock-hosted iron deposits. Conjugate iron-rich and silica-rich melt inclusions observed in thin-sections are considered as direct evidence for the presence of iron-rich melt, yet unequivocal outcrop-scale evidence of iron-rich melts are still lacking in volcanic rock-hosted iron deposits. Submarine volcanic rock-hosted iron deposits, which are mainly distributed in the western and eastern Tianshan Mountains in Xinjiang, are important resources of iron ores in China, but it remains unclear whether iron-rich melts have played a role in the mineralization of such iron ores. In this study, we observed abundant iron-rich agglomerates in the brecciated andesite lava of the Heijianshan submarine volcanic rock-hosted iron deposit, Eastern Tianshan, China. The iron-rich agglomerates occur as irregular and angular masses filling fractures of the host brecciated andesite lava. They show concentric potassic alteration with silicification or epidotization rims, indicative of their formation after the wall rocks. The iron-rich agglomerates have porphyritic and hyalopilitic textures, and locally display chilled margins in the contact zone with the host rocks. These features cannot be explained by hydrothermal replacement of wall rocks （brecciated andesite lava） which is free of vesicle and amygdale, rather they indicate direct crystallization of the iron-rich agglomerates from iron-rich melts. We propose that the iron-rich agglomerates were formed by open-space filling of volatile-rich iron-rich melt in fractures of the brecciated andesite lava. The iron-rich agglomerates are compositionally similar to the wall-rock brecciated andesite lava, but have much larger variation. Based on mineral assemblages, the iron-rich agglomerates are subdivided into five types, i.e., albite-magnetite type, albite-K-feldspar- magnetite type, K-feldspar-magnetite type, epidote-magnetite type

关键词： iron-rich agglomerates iron-rich melt volatile submarine volcanic iron deposit,Heijianshan Eastern Tianshan

Firms Quasi-dynamics in Chinese Manufacturing Industry

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China & World Economy 2022年第5期30卷 102-127页

作者： lixing li Qihong liu Changyu Ren China Center for Economic Research National School of DevelopmentPeking UniversityChina Department of Economics University of OklahomaUSA National School of Development Peking UniversityChina

We explore firm quasi-dynamics(entry,exit,and growth)in Chinese manufacturing industry and investigate how these dynamics vary across *** results show that relative to provinces with less developed economies,in provinces with more developed economies(i)there is a higher proportion of new firms;(i)new firms are smaller and more labor-intensive;(ii)firms exit at a quicker rate,and surviving firms grow *** results point toward cross-region differences in market efficiency in terms of how much it costs a firm to enter or exit the *** findings shed light on how firms should adapt their strategies across regions and how the government should create sound policies on industrial upgradingand relocation.

关键词： entry and exit firm dynamics industrial shift labor cost market thickness