新疆希勒库都克铜钼矿床硫同位素特征及成矿物质来源探讨  

Sulfur-isotope characteristics and discussion on the source of ore-forming material of the Xilekuduke Cu-Mo deposit,Xinjiang Province

作　　者：龙灵利[1,2] 王京彬[1,2] 王玉往[1,2] 王莉娟[1,2] 廖震[1,2] 赵路通[1,2] 孙志远[1,2] 高立明 

机构地区：[1]北京矿产地质研究院,北京100012 [2]有色金属矿产地质调查中心,北京100012 [3]中材地质工程勘察研究院有限公司,北京100102

出　　处：《岩石学报》2015年第2期545-554,共10页Acta Petrologica Sinica

基　　金：国家自然科学基金项目(41202064);国家重点基础发展研究计划项目(2014CB440803;2007CB411304)联合资助

摘　　要：位于东准噶尔北缘的希勒库都克铜钼矿床是一个以钼为主的斑岩型矿床,形成于早石炭世。希勒库都克铜钼矿床硫化物δ34S值介于+0.4‰^+7.6‰之间,平均为+4.1‰,其中黄铁矿δ34S值为+0.4‰^+7.6‰(平均+4.2‰)、辉钼矿δ34S值为+3.2‰^+4.7‰(平均+4.2‰)、黄铜矿δ34S值为+1.6‰^+2.5‰(平均+2.1‰),均显示出岩浆硫的组成特征。硫化物稀土元素特征与含矿斑岩类似,暗示成矿物质可能来源于含矿斑岩;流体包裹体地球化学及H-O同位素特征也表明成矿流体主要来自岩浆热液。而含矿斑岩高的正εNd(t)值、低的87Sr/86Sr初始比值表明含矿岩浆可能主要来自于地幔源区。综合研究区硫化物硫同位素、稀土元素及流体包裹体地球化学特征等分析,本文认为希勒库都克铜钼矿床成矿物质主要来自地幔源区,且含矿岩浆可能经历了地壳深部壳幔物质混合均一化的过程。The Xilekuduke Cu-Mo deposit is a molybdenum-rich porphyry deposit, which located in the northern margin of the East Junggar and formed at the Early Carboneferous. The δ34S values for the sulfide from the Xilekuduke deposit vary from 0.4%o to 7. 6‰, with an average of 4. 1‰. The δ34S values of pyrite, molybdenite and chalcopyrite show ranges of 0. 4%o -7. 6‰, 3.2‰ -4. 7‰ and 1.6‰ - 2. 5‰, with the averages of 4. 2‰, 4. 2‰ and 2. 1‰, respectively, indicating that the sulfur in the sulfides was sourced from a magma. REE geochemical characteristics of sulfides from the Xilekuduke deposit are similar to those of the ore-bearing porphyry, suggesting that the ore-forming materials were came from ore-beating porphyry. Fluid inclusions and H-O isotope systematic also indicate that ore-forming fluids were derived mainly from magma. While, the high positive ∑Nd （t） values and low 87 Sr/86 Sr initial ratios of the ore-bearing porphyry show that the ore-bearing magma sourced mainly from the mantle. We thus conclude that the ore-forming materials of the Xilekuduke Cu-Mo deposit were mainly sourced from the mantle, and the ore-bearing magma maybe undergone a process of mixing and uniformization between crust and mantle in deep crust.

关 键 词：希勒库都克铜钼矿 S同位素 成矿物质来源 东准噶尔北部 

分 类 号：P618.41[天文地球—矿床学] P618.65[天文地球—地质学]