摘要
易门凤山铜矿床是昆阳元古宙裂谷铜矿带易门式铜矿床的典型代表之一。该矿床明显受刺穿体构造控制，铜矿体赋存于昆阳群绿汁江组硅化碎裂白云岩中。根据刺穿体的宏观分布特征、岩石学和岩石地球化学特征，进一步剖析了控矿型刺穿体和非控矿型刺穿体两种类型：控矿型刺穿体岩石成份复杂，构造变形强，角砾状构造发育， MgO含量变化大（3.18%~15.64%）， FeO/Fe2O3值变化范围大（0.43~28.50），其形成机制与深部火山隐爆作用和强烈构造作用有关；而非控矿型刺穿体岩石成份简单，内部构造变形弱，角砾状构造不显著， MgO含量低（1.90%~3.77%）， FeO/Fe2O3值也低（0.14~0.56），其形成机制主要与强烈构造作用有关。建立了控矿与非控矿型两类刺穿体的岩石地球化学特征和识别标志。该标志对该类矿床的找矿预测具有实际意义。
TheYimen Fengshan copper deposit is one of the typical examples of copper deposit in the Kunyang rift basin, Yunnan province, China. The ore-bodies are located in the cataclastic dolomite of the Lvzhijiang Formation which was controlled by diapir structure. This study suggests that not all diapir hosts ore-bodies. Diapir may be divided into the ore-controlling type and non-ore-controlling type. The two types of diapirs have obviously different macro-distribution, petrography, and geochemical characteristics. The rocks from the ore-controlling type diapir have composition and pre-tectonic recrystallization more complex than these of the non-ore-controlling type diapir. Moreover, the rocks in the ore-controlling type diapir are closely related to crypto-explosionsas indicated by the intermediate-acid crystal tuff breccias and dacite breccias. In addition, the geochemical characteristics of rocks from the ore-controlling type diapir have higher MgO contents （3.18% to 15.64%）, and widely varied FeO/Fe2O3 ratios （0.43-28.50）, whereas the tuffite and sericite slate from the non-ore-controlling type diapir have lower MgO contents （1.90%-3.77%,） and narrow ranges of FeO/Fe2O3 ratios （0.14-0.56）. Therefore, the establishment of the distinguish characteristics for the ore-controlling type and the non-ore-controlling type diapirs is very important for future exploration of the Fengshan-type copper deposit.
出处
《大地构造与成矿学》
EI
CAS
CSCD
北大核心
2014年第4期822-832,共11页
Geotectonica et Metallogenia
基金
国家科技支撑项目(编号:2006BAB01B09)
全国危机矿山专项(编号:20089943)
云南省科技计划项目(编号:2011FZ027)
国家自然科学青年基金(批准号:41202069)
云南省矿产资源预测评价工程实验室(2010)及省
校创新团队项目(2012
2009)资助
关键词
刺穿体分类
找矿预测
易门凤山铜矿床
刺穿体空间分布规律
diapir classification prospecting Fengshan-type copper deposit spatial distribution of diapir
