摘要
科克萨依金矿位于新疆北部青河县境内,额尔齐斯构造-成矿带东南的布尔根地区。通过野外调查和室内综合研究,对其构造-蚀变、成矿流体进行了详细分析,讨论了构造-流体演化特征。研究表明:(1)金矿化与韧性剪切带的构造-蚀变作用密切相关,糜棱岩化强烈,强片理化、亚晶、变形纹、流动构造等结构发育。SEM-CL显示重结晶结构、溶解结构以及多期复合剪切结构特征,表明变形变质作用强烈。伴随构造-热液活动,硅化、黄铁矿化强烈,并具一定的空间分带,与金矿化关系密切。(2)包裹体类型有L_(H_2O)-V_(H_2O)、L_(H_2O)-L_(CO_2)、L_(H_2O)型三种,流体的演化表现为早期中高温、低盐度、富CO_2,随着中晚期阶段剪切带变形增强导致变形分解以及裂隙愈合,逐渐演化成中低温、低盐度的富H_2O流体。(3)科克萨依金矿具有造山型金矿特点,剪切带构造-热液蚀变为主要的控矿因素,其构造-成矿流体的演化特征与剪切带演化过程吻合。
The Kekesayi gold deposit is located in the Buergen ductile shear zone in the southern margin of Altay, Qinghe County, Xinjiang. The deposit consists of altered mylonite type and gold-bearing quartz veins type ores. The main ore-bearing rocks are gray metamorphic tuffs of the Tuoranggekuduke Formation. The ores are mostly lenticular and vein, and are strictly controlled by shear bands. Through field investigation, sample collection and laboratory identification, the structural alteration characteristics are studied in detail. The microstructure of quartz is analyzed by SEM cathodoluminescence（SEM-CL）. The fluid inclusions of the deposit were studied by means of micro-temperature measurement and laser Raman analysis, and the tectonic-fluid evolution characteristics were discussed. Our results showed that：（1） The gold mineralization is closely related to the structural alteration of the ductile shear zone. The mylonitization, subgrain deformation and fluid structure are developed in the mining area. The recrystallized texture, dissolution structure and multistage composite shear structure characteristics of SEM-CL show that the deformation and metamorphism are very strong. The tectonic-hydrothermal activity resulted in strong silicification and pyritization and closely related to gold mineralization.（2） The fluid inclusions of quartz veins in the mineralized rocks are distributed in groups and the morphology of the fluid inclusions are mostly oval and tadpole in shape. The primary fluid inclusions are distributed in disorder, and the secondary fluid inclusions distribute linearly along the fissures mostly elongated owing to the strong tectonic deformation. Fluid inclusions are not of uniform size, generally are 8-20 μm. The types of inclusions can be classified according to the petrography and micro temperature measurement： two phase aqueous solution type（L（H2O）-V（H2O） ）, carbon-rich type（L（H2O） -L（CO2） ） and single phase aqueous solution type（L（H2O） ）. The evolution
作者
王颖维
徐九华
丁汝福
卫晓锋
张辉
成曦晖
张泽阳
WANG Yingwei1, XU Jiuhua1, DING Rufu2, 3, WEI Xiaofeng4, ZHANG Hui1, CHENG Xihui1 and ZHANG Zeyang1(1. Department of Resource Engineering, Beijing University of Science and Technology, Beijing 100083, China; 2. China Non-Ferrous Metals Resources Geological Survey, Beijing 100012, China; 3. China Nonferrous Metals （Guilin） Geology and Mining Co. Ltd., Guilin 541004, Guangxi, China; 4. Beijing Institute of Geology for Mineral Resources, Beijing 100012, China)
出处
《大地构造与成矿学》
EI
CAS
CSCD
北大核心
2018年第3期520-533,共14页
Geotectonica et Metallogenia
基金
国家自然科学基金项目(41672070,41372096)
广西特聘专家专项经费联合资助
