甘肃金川铜镍硫化物矿床成岩成矿构造观测及解析  

Observation and Analysis of Diagenesis and Mineralization Structures of the Jinchuan Cu-Ni Sulfide Depositin Gansu

作　　者：焦建刚[1,2,3] 谭福 李林娜 刘健 杨兴科[1] 高栋[4] JIAO Jiangang;TAN Fu;LI Linna;LIU Jian;YANG Xingke;GAO Dong(School of Earth Science and Resources,Chang'an University,Xi'an,Shaanxi710054,China;Key Laboratory of Western China's Mineral Resources and Geological Engineering,Ministry of Education,Xi'an,Shaanxi710054,China;Xi'an Key Laboratory for Mineralization and Efficient Utilization of Critical Metals,Xi'an,Shaanxi710054,China;School of Geographical Sciences,Lingnan Normal University,Zhanjiang,Guangdong524048,China)

机构地区：[1]长安大学地球科学与资源学院,陕西西安710054 [2]西部矿产资源与地质工程教育部重点实验室,陕西西安710054 [3]西安市关键金属成矿与高效利用重点实验室,陕西西安710054 [4]岭南师范学院地理科学学院,广东湛江524048

出　　处：《现代地质》2024年第4期1026-1042,共17页Geoscience

基　　金：国家自然科学基金项目(92162213);中国地质调查局“祁连—秦岭成矿带战略性矿产调查”项目(102202240090000000001);内蒙古自治区地质勘查基金项目(2020-KY05)。

摘　　要：甘肃金川超大型铜镍硫化物矿床形成于新元古代,从其母岩浆侵位到后期构造叠加改造,该矿床经历了复杂的地质演化过程。尽管前人开展了相关研究,但是关于该矿床的矿区构造研究仍然存在较大争议。此外,厘清矿区控岩控矿构造对探讨岩浆侵入与就位过程、矿床深部找矿等具有重要意义。本次研究根据矿区构造分类、配套、交切关系与成岩成矿时序组合等,划分出成矿前、成矿期和成矿后构造系统,借助断裂、共轭节理产状统计分析了矿区构造应力场,确定主压应力方向分别为N-S向、NE-SW向和NNE-SSW向。最后将矿区构造与区域大地构造演化相结合,总结归纳出成矿前、成矿期与成矿后构造演化过程:成矿前经历吕梁运动阶段,该区发生强烈褶皱和变质作用。成矿期晋宁运动阶段,金川赋矿岩体的母岩浆沿着吕梁期形成的褶皱构造虚脱空间侵入就位。成矿后,加里东运动阶段,龙首山地区发生陆内造山,大量基性岩脉侵入;海西运动阶段,推覆造山运动强烈,形成泥盆纪地层,发育一系列同斜紧闭褶皱;燕山运动阶段,挤压-走滑作用占主导形成东西向展布的山前拉分盆地和北东向展布的断陷盆地;喜马拉雅运动阶段,急剧隆升和剥蚀,金川矿床从深部被抬升到了地表。研究成果为金川矿床深、边部找矿提供了新思路。The Jinchuan giant Cu-Ni sulfide deposit in Gansu formed during the Neoproterozoic.From the ini-tial emplacement of its parent magma to subsequent tectonic superposition,this deposit has undergone a complex geological evolution.Despite the fact that many previous studies have been conducted,significant controversy regarding the tectonics of the deposits still remains.Furthermore,it is of great significance to clarify the rock-and ore-controlling structures for magma intrusion and its emplacement processes,as well as to prospect for ore deposits at depths.In this study,we analyzed the stress field based on the classification,correlation,cross-cut-ting relationships,and chronological sequence of structures in the deposit area,using nodal production statis-tics.In the end,we determined three primary compressive stress directions:N-S,NE-SW,and NNE-SSW.Finally,by integrating regional and mining tectonics,we concluded that there are six stages of tectonic evolution in the Longshoushan area:Lüliang,Jinning,Caledonian,Hercynian,Yanshan,and Himalayan.We also es-tablished a model of tectonic evolution for the Jinchuan Cu-Ni sulfide deposit,including the pre-,syn-,and post-mineralization stages.The model for the tectonic evolution of the Jinchuan Cu-Ni sulfide deposit illustrates the emplacement of parental magma to form the deposit,providing new insights into mineral prospecting in both within the deposit and in its periphery.

关 键 词：甘肃金川 铜镍硫化物矿床 构造解析 构造演化 

分 类 号：P542.3[天文地球—构造地质学] P551[天文地球—地质学]