西藏那不定铅锌矿床S、Pb、H、O同位素组成及成矿物质来源示踪  

Sulfur and lead isotope composition and tracing for sources of ore-forming materials in the Nabuding Pb-Zn deposits in Tibet

作　　者：王琳[1] 李志军[1] 韩泽伟 WANG lin;LI Zhi-jun;HAN Ze-wei(Chengdu University of Technology,Chengdu,Sichuan 610059;Changzhi college,Changzhi,Shanxi 046011)

机构地区：[1]成都理工大学,四川成都610059 [2]长治学院,山西长治046011

出　　处：《四川冶金》2023年第1期22-30,共9页Sichuan Metallurgy

基　　金：中国地质调查局区域地质调查项目(编号:DD20160015-12);四川省科技厅基础研究项目(2020YJ0427)联合资助。

摘　　要：西藏那不定铅锌矿床位于冈底斯成矿带中东段,是新发现的矽卡岩型铅锌矿床,目前研究程度较低。本文在野外地质调查的基础上,运用S、Pb同位素研究方法,对那不定铅锌矿床的物质来源进行初步的探讨。结果显示:(1)那不定铅锌矿石金属硫化物的δ^(34)SV-CDT值分布范围较宽,主要集中在-2.0‰~6‰之间,在硫同位素直方图上呈塔式分布,总体具有黄铁矿>闪锌矿>方铅矿的特征;(2)铅同位素组成比较均一,同位素比值变化较小,显示出普通铅的特征,显示出铅同位素来源以上地壳铅为主,少量造山带铅相结合的特征;(3)将那不定矿床6件脉石矿物中石英包裹体氢同位素值在-83.5‰~167.8‰之间,石英包裹体中δ^(18)O水‰值在-2.81‰~3.6‰范围内,显示明显受到大气降水加入。The Nading lead-zinc deposit in Tibet is located in the middle and eastern part of the Gangdise metallogenic belt.It is a newly discovered skarn-type Pb-Zn deposit with a low degree of research.On the basis of field geological survey,this paper makes a preliminary discussion on the material source of Nading lead-zinc deposit by using S and Pb isotope research methods.The results show that:(1)the distribution range ofδ^(34)SV-CDTvalue of Nading lead-zinc ore metal sulfide is wide,mainly concentrated in the range of-2.0‰-6‰,showing a tower distribution on the sulfur isotope histogram,with the characteristics of pyrite>sphalerite>calcite;(2)the composition of lead isotope is relatively uniform,and the change of isotope ratio is small,which shows the characteristics of ordinary lead,and shows that the lead isotope source is mainly from the upper crust and a small amount of orogenic belt lead;(3)The hydrogen isotope values of the quartz inclusions in the six gangue minerals of the Nading deposit are between-83.5‰-167.8‰,and theδ^(18)O water values of the quartz inclusions are between-2.81‰-3.6‰,indicating that they are obviously added by atmospheric precipitation.

关 键 词：硫同位素 铅同位素 成矿物质来源 铅锌矿床 矽卡岩型 氢氧同位素 

分 类 号：P6[天文地球—地质学]