广西佛子冲铅锌矿田火成岩的时空序列及其对成矿时限的约束  

Constraints on Metallogenic Time and Time-Space Serial of Igneous Rocks of Fozichong Ore Field in Guangxi Zhuang Autonomous Region

作　　者：秦亚[1] 杨启军[1] 李程[1] 周叔齐 许浩天 Qin Ya;Yang Qijun;Li Cheng;Zhou Shuqi;Xu Haotian(Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration,Guilin University of Technology,Guilin 541004,Guangxi,China)

机构地区：[1]桂林理工大学广西隐伏金属矿产勘查重点实验室,广西桂林541004

出　　处：《吉林大学学报（地球科学版）》2019年第2期425-444,共20页Journal of Jilin University：Earth Science Edition

基　　金：广西壮族自治区国土资源厅找矿突破战略行动地质矿产勘查项目(桂国土资函[2016]429);国家自然科学基金项目(41572191);广西自然科学基金项目(2017GXNSFBA198166;2018GXNSFAA281248);有色及贵金属隐伏矿床勘查教育部工程研究中心项目(2018GCZX004);广西科技计划项目(桂科AD16450001)~~

摘　　要：广西佛子冲铅锌矿田火成岩的主要岩石类型有花岗岩、花岗斑岩、花岗闪长岩(石英闪长岩)、花岗闪长斑岩、少斑花岗斑岩、英安斑岩和凝灰岩等。本文共进行了14件火成岩样品的LA-ICP-MS锆石UPb测年,其中大冲石英闪长岩侵位于海西期二叠纪((256.8±2.0)Ma),糯垌岩体((152.6±1.2)Ma)和广平岩体((152.9±2.9)Ma)形成于燕山早期晚侏罗世,花岗斑岩、少斑花岗斑岩、花岗闪长斑岩、英安斑岩和火山角砾凝灰岩形成于燕山晚期早白垩世(约100Ma)。结合前人的研究成果及14件火成岩样品的测年结果,构建该区火成岩的年代学序列,确定其侵位时代主要集中在志留纪(约440Ma)、二叠纪末期(约256Ma)、晚侏罗世(约152Ma)、早白垩世晚期(约100Ma)。根据佛子冲铅锌矿的空间展布、矿体特征以及与火成岩的关系,确定花岗斑岩为成矿地质体,进而限定其成矿时代为早白垩世晚期(约100Ma)。The main rock types of igneous rocks in Fozichong ore field are granite,granite porphyry,granodiorite(quartz diorite),granodiorite porphyry,dacite porphyry and tuff.We measured the ages of14 igneous rock samples in this area by LA-ICP-MS zircon U-Pb dating.The Dachong quartz diorite was formed in Permian((256.8±2.0)Ma);Nuodong Pluton((152.6±1.2)Ma)and Guangping Pluton((152.9±2.9)Ma)were formed in the Late Jurassic of Yanshanian;granite porphyry,granite diorite porphyry,less spot granite porphyry,granite diorite porphyry,dacite porphyry and tuff were formed in the Early Cretaceous of Yanshanian(100 Ma±).The ages of the igneous rocks in Fozichong ore field are mainly concentrated in Silurian(440 Ma±),Late Permian(256 Ma±),Late Jurassic(152 Ma±),and late Early Cretaceous(100 Ma±).According to the spatial distribution,ore body characteristics and the relationship with igneous rocks,the granite porphyry is considered to be the metallogenic geological body,and the metallogenic age is defined as the late Early Cretaceous(about 100 Ma).

关 键 词：火成岩 年代学 成矿时代 佛子冲铅锌矿田 

分 类 号：P588.1[天文地球—岩石学]