内蒙古图古日格金矿床中碲化物的发现及其地质意义  

Discovery and geological significance of tellurides in theTugurige gold deposit in Inner Mongolia

作　　者：丁成武 戴盼 江思宏[2] 郝金华 张照录[1] 刘琦 彭云彪[4] 张更信 DING Chengwu;DAI Pan;JIANG Sihong;HAO Jinhua;ZHANG Zhaolu;LIU Qi;PENG Yunbiao;ZHANG Gengxin(School of Resources and Environmental Engineering,Shandong University of Technology,Zibo,Shandong 255000,China;Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Institute of Earth Sciences,China University of Geosciences(Beijing),Beijing 100083,China;208 Geological Party,China National Nuclear corporation,Baotou,Inner Mongolia 014010,China)

机构地区：[1]山东理工大学资源与环境工程学院,山东淄博255000 [2]中国地质科学院矿产资源研究所,北京100037 [3]中国地质大学(北京)科学研究院,北京100083 [4]核工业208大队,内蒙古包头014010

出　　处：《地质学报》2022年第7期2450-2463,共14页Acta Geologica Sinica

基　　金：国家自然科学基金项目(编号42002099);国家自然科学基金项目(编号41973048)资助的成果;山东省重点研发计划项目(编号2019GSF109101);山东省自然科学基金青年基金项目(编号ZR2018QD002);山东省地质勘查项目(编号SDGP370000202002001782)。

摘　　要：图古日格金矿床是兴蒙造山带内的一个大型石英脉型金矿床,矿床的矿化与矿区内的钙碱性花岗质岩浆活动存在密切的成因联系。与钙碱性岩浆活动有关的富碲金矿床比较少见;具有富碲特征的金矿床,在兴蒙造山带内也鲜有报道。本次研究通过矿相学观察和电子探针分析,在图古日格金矿床矿石中发现了大量碲化物,包括碲金矿、六方碲银矿、碲金银矿和自然碲等,矿床中金的赋存形式主要为碲化物,其次为自然金和银金矿。图古日格金矿床的主成矿阶段(Ⅱ,石英多金属硫化物阶段)从早到晚可划分为Ⅱ_(1)、Ⅱ_(2)和Ⅱ_(3)三个亚阶段。Ⅱ_(1)阶段的矿物组合为粗粒黄铁矿+六方碲银矿+碲金银矿+自然碲+粒状方铅矿;Ⅱ_(2)阶段的矿物组合为细粒黄铁矿+碲金矿+碲金银矿+碲铅矿;Ⅱ_(3)阶段的矿物组合为自然金+银金矿+脉状方铅矿。碲化物和硫化物共生组合显示,Ⅱ_(1)阶段成矿流体的lgf_(S2)为-13.5~-10.9,lgf_(Te2)为-10.5~-9.4;Ⅱ_(2)阶段成矿流体的lgf_(S2)为-16.7~-12.4,lgf_(Te2)为-11.2~-9.4。流体演化过程中发生的沸腾作用及含H_(2)Te气相流体的冷凝作用是诱发该矿床大量金、银碲化物从成矿流体中沉淀并富集的主要机制,也是造成该矿床成矿流体中的碲含量不均匀,并且出现自然碲+硫化物等不平衡矿物组合的原因。The Tugurige gold deposit is a large tonnage quartz-vein type deposit in the western part of the Xing’an-Mongolia Orogenic Belt(XMOB).The gold mineralization and calc-alkalic granitic magmatism of this deposit have very close genetic relationships.Te-rich gold deposits associated with calc-alkalic granitic magmatism are relatively rare,and this kind of Te-rich gold deposits is rarely reported in the XMOB.Based on optical microscope and electron probe micro-analysis(EPMA),for the first time a large number of the tellurides were discovered in the ore samples of the Tugurige gold deposit,such as calaverite,stutzite,petzite and native tellurium.The gold and silver of this deposit are primarily occurring as Au-and Ag-tellurides,with a small amount of native gold and electrum.The main mineralization stage(Ⅱ,auriferous quartz-polymetallic sulfide stage) of this deposit can be divided into three sub-stages from early to late,namely,Ⅱ_(1),Ⅱ_(2),and Ⅱ_(3)-stage.The mineral assemblages of Ⅱ_(1),Ⅱ_(2),and Ⅱ_(3)-stage are coarse pyrite-stutzite-petzite-native tellurium-galena,fine-grained pyrite-calaverite-petzite-altaite,and native gold-electrum-galena,respectively.The mineral assemblage characteristics indicate that,in Ⅱ_(1)-stage of mineralization,the lgf_(S2) and lgf_(Te2) values of ore forming fluids ranged from-13.5 to-10.9 and from-10.5 to-9.4.The lgf_(S2) and lgf_(Te2) values of ore forming fluids in Ⅱ_(2)-stage ranged from-16.7 to-12.4 and from-11.2 to-9.4,respectively.Fluid boiling and condensation of H_(2)Te-bearing vapors were the dominant controls on precipitation of the Au and Ag telluride ores,and occurrence of inhomogenous native tellurium-sulfide mineral assemblages.

关 键 词：碲化物 钙碱性岩 图古日格金矿床 兴蒙造山带 

分 类 号：P618.51[天文地球—矿床学]