新疆阿吾拉勒山奴拉赛铜矿床流体包裹体和稳定同位素研究  

Fluid inclusion and stable isotope studies of Nulasai copper deposit in Awulale Mountain,Xinjiang

作　　者：张贺[1] 刘敏[2] 赵军[3,4] 朱维娜 

机构地区：[1]中国地质大学地球科学与资源学院,北京100083 [2]中国地质科学院矿产资源研究所,北京100037 [3]长安大学地球科学与资源学院,陕西西安710054 [4]中国人民武装警察部队黄金第八支队,新疆乌鲁木齐830057

出　　处：《矿床地质》2012年第5期1087-1100,共14页Mineral Deposits

基　　金：国家科技支撑计划(2011BAB06B02-05);地质矿产调查评价项目(1212011085060)联合资助

摘　　要：阿吾拉勒铜矿成矿带是西天山重要的铜矿产地,奴拉赛铜矿床是成矿带内典型的铜矿床。在对奴拉赛铜矿床的地质特征研究的基础上,对流体包裹体和稳定同位素进行了研究。结果表明,流体包裹体均一温度变化于107~332℃,盐度介于0.7%~19.5%,密度范围是0.94 g/cm3~1.13 g/cm3。矿石中金属硫化物δ34SV-CDT变化范围较大,在-4.1‰^+8.5‰之间;重晶石δ34SV-CDT在+13.9‰^+17.0‰之间。矿石中方解石的δ18OSMOW变化于+12.6‰^+16.3‰,δ13CV-PDB在-10.1‰^-2.3‰之间。认为奴拉赛铜矿床属于中低温热液成因,而非次生富集成矿,成矿过程为一期多阶段。流体混合是金属沉淀的主要机制,随着热液的演化,温度降低和氧逸度升高等多种因素耦合导致铜-硫络合物失稳而在断裂构造中沉淀出大量铜矿物。奴拉赛铜矿床与莫斯早特岩体在时间和空间上紧密相关,推测莫斯早特岩体为成矿提供了热源和主要物源。The Awulale Mountain copper metallogenic belt is a major copper producing area in Western Tianshan, and the Nulasai copper deposit is a typical small- size copper deposit. The authors carried out a systematic study of the geological features as well as the origin and evolution of metallogenic fluids in the Nulasai copper deposit. Experimental results show that fluid inclusions have a homogenization temperature range of 107- 332℃, a salinity range of 0.7%--19.5%, and a density range of 0.94 g/cm3--1.13 g/cm3. B34Sv_cm- of ore metal sul- fides range between -4.1‰ and ＋ 8.5‰, δ34Sv-CDT of barites range between ＋ 13.9‰ and ＋ 17.0‰, B18OsMow of ore calcite range between ＋ 12.6‰ and ＋ 16.3‰, and δ13Cv-PDB vary between - 10.1‰ and- 2. 3‰. Characteristics of ores, mineral phases, fluid inclusions and stable isotopes show that the Nulasai cop- per deposit belongs to middle-low temperature hydrothermal metallogeny, rather than secondary enrichment metallogeny. The metallogenic process belongs to one period consisting of four stages. Fluid mixing of pneuma- tolito-hydrothermal fluids played a key role in metallogeny. Meanwhile, along with the evolution of the hy- drothermal fluids, the combination of a few factors such as decreasing temperature, increasing oxygen fugacity and decreasing pH resulted in the deposition of sulfides in faults. The Nulasai copper deposit and the Mosizaote rock mass are closely related to each other in time and space. The original fluids of Nulasai were derived from pneumatolito-hydrothermal fluids, and Mosizaote provided heat for metallogenic process.

关 键 词：地球化学 铜矿 流体包裹体 稳定同位素 奴拉赛 阿吾拉勒 

分 类 号：P618.41[天文地球—矿床学]