江西景德镇朱溪浅部铜矿床地质、同位素地球化学特征  

Geology and isotopic geochemistry of the Zhuxi shallow copper deposit in Jingdezhen, Jiangxi Province

作　　者：李兴俭[1,2] 张达 霍海龙[3] 贺晓龙 狄永军 欧阳永鹏[4] 陈祺 LI Xing-jian;ZHANG Da;HUO Hai-long;HE Xiao-long;DI Yong-jun;OUYANG Yong-peng;CHEN Qi(School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China;Xinjiang Institute of Geology and Mineral Resources, Urumqi 830000, China;Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China;912 Geological Team, Jiangxi Bureau of Geology and Mineral Resources, Yingtan 335001, China)

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]新疆维吾尔自治区地质矿产研究所,新疆乌鲁木齐830000 [3]中国地质科学院地质力学研究所,北京100081 [4]江西省地质矿产勘查开发局九一二大队,江西鹰潭335001

出　　处：《地球化学》2018年第6期685-698,共14页Geochimica

基　　金：国家自然科学基金项目(41772069);国土资源部公益性行业科研专项(201411035-3)

摘　　要：江西景德镇朱溪浅部铜矿床位于萍乐凹陷带北缘,属塔前-赋春有色金属成矿带北部,为近年来发现的大型钨铜多金属矿床浅部的铜矿床。矿体分布受到断裂构造的控制,金属矿物组成主要为黄铜矿、闪锌矿、磁黄铁矿、斑铜矿、辉铜矿、黄铁矿和少量白钨矿等。文中重点分析了矿床脉石矿物的氢、氧、碳同位素和矿石硫化物的硫、铅同位素地球化学特征。研究结果显示:金属硫化物δ^(34)S_(CDT)集中为1.1‰~2.5‰,平均为1.63‰(n=6),极差为1.4‰;石英和方解石δ^(18)O_(water)值的变化范围较大(-0.2‰^+6.65‰,n=10),均值为2.19‰;石英δD_(V-SMOW)值的变化范围比较集中(-81.1‰^-106.4‰,n=5);方解石δ^(13)C_(PDB)变化范围为-5.1‰^-7.7‰,平均为-6.28‰(n=5);7件硫化物样品的铅同位素组成为^(206)Pb/^(204)Pb=38.417~38.500、^(207)Pb/^(204)Pb=15.605~15.652和^(208)Pb/^(204)Pb=18.206~18.553,矿石硫化物铅同位素基本为正常的放射成因铅。矿石硫化物的硫同位素及方解石的碳同位素均指示成矿物质可能来源于深部岩浆活动并受到低温蚀变作用;石英和方解石的氢氧同位素组成表明成矿流体早期以岩浆流体为主,成矿晚期加入了大量加热补给的大气降水;铅同位素组成表明成矿物质中Pb主要来源于陆内造山作用过程中形成的壳源重熔花岗岩。该矿床可能主要受华南中生代岩石圈多阶段伸展-减薄而形成的一系列地壳重熔型花岗质岩石控制,成因类型属于热液脉状充填型铜矿床。The Zhuxi shallow copper deposit is located in the northern part of the Taqian-Fuchun metallogenic belt,which is part of a large copper-tungsten deposit that was discovered in recent years. The ore body is totally controlled by the fault structure, and the main metallic minerals are chalcopyrite, sphalerite, pyrrhotite, bonite,chalcocite,pyrite,scheelite,etc. In this study,the authors focused on the isotopic geochemical characteristics of the sulfur, hydrogen, oxygen, carbon, and lead isotopes of the deposit. The results showed that the δ34SCDT values ranged from 1.1‰ to 2.5‰ with an average of 1.63‰(n = 6); the δ18Owater values ranged from-0.2‰ to 6.65‰with an average of 2.19‰(n = 10); the δDV-SMOW values ranged from-81.1‰ to-106.4‰(n = 5); the δ13CPDBvalues ranged from-5.1% to-7.7‰ with an average of-6.28‰(n = 5); the 206Pb/204Pb, 207Pb/204Pb, and208Pb/204Pb values of seven samples ranged from 38.417-38.500, 15.605-15.652, and 18.206-18.553, respectively;and the lead isotope compositions showed that all the lead belonged to normal radiogenic lead. The sulfur and carbon isotopes suggested that the ore-forming materials were mainly derived from deep magmatic activity and were affected by low-temperature alteration. Hydrogen and oxygen isotope compositions of quartz and calcite indicated that the ore-forming fluids were dominated by magmatic fluid in the early stage and mineralized with the addition of a large amount of heating recharge atmospheric precipitation in the late stage. The lead isotope composition indicated that the lead in the ore-forming materials was mainly derived from crust-sourced remelted granite formed during the intracontinental orogeny. This deposit may be dominated by a series of crustal remelted granitic rocks formed by multi-stage extensional thinning of the Mesozoic lithosphere in South China. The genetic type belongs to the hydrothermal vein-filling copper deposit.

关 键 词：浅部铜矿床 同位素地球化学 矿床成因 朱溪 江西 

分 类 号：P597[天文地球—地球化学] P618.14[天文地球—地质学]