湘南铜山岭铜多金属矿田成岩成矿作用年代学研究  

Rock-Forming and Ore-Forming Ages of Tongshanling Copper Polymetallic Ore-Field in Southern Hunan Province

作　　者：卢友月[1,2] 付建明[1,2] 程顺波[1,2] 刘树生[3] 黎传标 张利国[1] 马丽艳[1,2] 

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430205 [2]中国地质调查局花岗岩成岩成矿地质研究中心,湖北武汉430205 [3]湖南省地质矿产勘查开发局405队,湖南吉首416007 [4]湖南省湘南地质勘察院,湖南郴州423000

出　　处：《大地构造与成矿学》2015年第6期1061-1071,共11页Geotectonica et Metallogenia

基　　金：中国地质调查局地质矿产调查评价专项"南岭成矿带重要金属矿床成矿规律研究与选区评价"(1212011120804);"南岭成矿带资源远景调查评价"(12120114084501)及"中南重大岩浆事件及其成矿作用和构造背景综合研究"(12120114020701)联合资助

摘　　要：湘南铜山岭铜多金属矿田位于钦杭成矿带的中部,矿床主要产于铜山岭岩体接触带及其附近。本文对矿田内的岩体和矿床进行了精细的年代学研究,分别获得铜山岭Ⅰ号岩体的花岗闪长斑岩SHRIMP锆石U-Pb年龄为157±2 Ma(MSWD=1.20);铜山岭矿床石英脉型矿体中的辉钼矿Re-Os模式年龄为161±1 Ma(MSWD=0.21);桥头铺矿床矽卡岩型矿体中的辉钼矿Re-Os模式年龄为155±3 Ma(MSWD=1.5)、石榴子石Sm-Nd等时线年龄为155±8 Ma(MSWD=0.41)。成岩与成矿年龄在误差范围内基本一致,说明铜山岭矿田成岩成矿具有同时性,它们之间具有密切的成因联系。辉钼矿中Re含量(32.95×10^(-6)~59.45×10^(-6))指示成矿作用可能与壳幔混合作用有关。这为进一步研究区域成矿规律提供了重要同位素年代学依据。Tongshanling Copper polymetallic ore-field is located in the center of Qin-Hang（Qinzhou bay to Hangzhou bay） metallogenic belt. The orebodies are located nearby the contact zone of the Tongshanling pluton. This article presents the precise chronology study on the rock and ore deposits in the Tongshanling ore-field using different isotopic dating methods. Zircon SHRIMP U-Pb age of the granodiorite porphyry from the No.I Tongshanling pluton is 157±2 Ma（MSWD=1.20）; Re-Os dating of molybdenite from the quartz-vein ore bodie in Tongshanling deposit gives a model age of 161±1 Ma（MSWD=0.21）; Re-Os dating of molybdenite from the skarn ore bodie in Qiaotoupu deposit gives a model age of 155±3 Ma（MSWD=1.5）, related Sm-Nd isochron age of the garnet is 155±8 Ma（MSWD=0.41）. These ages suggest that both granitic rocks and ore deposits at Tongshanling ore-field have the same formational ages, which indicate that the granodioritic porphyry is genetically related to the ore-field. The Re contents of molybdenite（32.95×10^-6-59.45×10^-6） indicate that the ore-forming materials are maybe derived from the mixing of mantle and crust. Our new data provide important isotope chronology evidence for further study of the regional mineralization rules.

关 键 词：铜多金属矿田 SHRIMP锆石U-PB定年 辉钼矿RE-OS定年 石榴子石Sm-Nd定年 铜山岭 湘南 

分 类 号：P597[天文地球—地球化学] P611[天文地球—地质学]