陕西省黑龙口清岩沟钼-镍矿床地质特征与成因  

Geological features and genesis of the Qingyangou molybdenum-nickel deposit in Heilongkou,Shaanxi Province

作　　者：宗静婷[1,2] 张复新[1] 郑炜 侯俊富[1] 

机构地区：[1]大陆动力学国家重点实验室(西北大学),西北大学地质学系,陕西西安710069 [2]西安文理学院资源环境系,陕西西安710065 [3]西北有色地勘局物探队,陕西西安710054

出　　处：《中国地质》2010年第5期1501-1510,共10页Geology in China

基　　金：国家自然科学基金项目(40572065)资助

摘　　要：北秦岭奥陶系下段庙湾组黑色岩系中,含炭质泥板泥灰岩系Mo-Ni-Ti-Cu-Pb-Zn-P丰度较高,勘查出钼-镍硫化物矿床,在秦岭造山带中尚属首例。矿床产于商—丹带秦岭北部弧后断陷盆地深水沉积环境之中,严格受炭质千枚岩与细晶大理岩之间的韧-脆性构造接触带控制,矿体呈构造透镜体-扁豆体状。具有较强烈的辉钼矿化-磁黄铁矿化-镍黄铁矿化-黄铁矿化-闪锌矿化,伴随石墨化-硅化-铁白云石化-方解石化蚀变。矿体中镍-钼硫化物具有共生特点。矿石类型按容矿围岩划分为炭质千枚岩型、白云岩型和细晶大理岩型,按成矿元素组合划分具有镍-钼型、钼-石墨型、镍-多金属类型。矿床属于黑色岩系为容矿的沉积预富集-变质叠加活化迁移-韧脆性构造改造和热液富集成矿的层控型后生高-中-低温热液成因。It is for the first time that a molybdenum-nickel sulfide deposit was discovered in the black rock series of the Qinling orogenic belt.The ore deposit has relatively abundant Mo-Ni-Ti-Cu-Pb-Zn-P in carbonaceous marl series,i.e.,black rock series of lower Ordovician Miaowan Formation in North Qinling.The tectonic setting of the ore deposit is a deep water sedimentary environment of the back-arc rift basin along Shang-Dan fault zone in North Qinling,and the ore deposit is strictly controlled by the ductile-brittle tectonic contact zone between carbonaceous phyllite and fine-grained marble.The ore bodies assume the forms of tectonic lenses and pods.The alteration types include relatively strong molybdenitization,pyrrhotitization,pyritization and sphaleritization,associated with graphitization,silicification,ankeritization and calcitization.Nickel sulfides and molybdenum sulfides are associated with each other in the ore deposit.The ore types can be classified into carbonaceous phyllite type,dolomite type and fine-grained marble type in accordance with ore rocks,and into Ni-Mo type,molybdenum-graphite type and nickel polymetallic type in accordance with metal elements.The ore deposit is genetically of epigenetic stratabound high-medium-low temperature hydrothermal type.The ore-forming process experienced such stages as initial enrichment of useful components in black rock series,metamorphic activation migration of useful components,ductile-brittle structural transformation and hydrothermal ore enrichment.

关 键 词：黑色岩系 钼-镍矿床 成矿机制 清岩沟 北秦岭 

分 类 号：P618.51[天文地球—矿床学]