滇西北红牛—红山铜矿床构造特征与成矿关系研究

Research on relation of mineralization to structures in Hongniu-Hongshan Cu deposit in Northwest Yunnan province

红牛—红山铜矿区位于义敦岛弧南段之格咱压性弧,矿床类型为与燕山晚期花岗岩有关的斑岩矽卡岩型铁铜多金属矿床,矿床规模为大型。通过系统开展矿区构造地质调查,构建矿区“源-运-储-破”构造体系,结果表明,矿区构造格架为沉积构造、侵入构造、褶皱构造及断裂构造等构造系统叠加复合而成。沉积构造系统为主要成矿前赋矿构造,侵入构造系统为成矿前或成矿期导矿、赋矿构造,褶皱构造系统及断裂构造系统具有多期活动特征。断裂构造同时具有压扭性、张扭性及平移断裂等多性质叠加特征,主要呈NW-NNW向展布。成矿前红牛向斜对矿区成矿的空间分布具有决定性作用,矿体均产于红牛向斜中,同时成矿前红山断裂及次级断裂具导矿、配矿、赋矿作用,控制矿区成矿地质体的产出形态及范围,决定成矿的时间和空间范围。成矿期节理裂隙系统丰富了矿区成矿容矿空间,而成矿后断裂及次级小褶皱对矿区矿体进行破坏和改造,形成现今矿床特征。

The Cu Deposit is located at the Gaza compressional arc of the South Yidun island arc.It is a large-sized one belonging to late Yanshanian granite-related porphry-skarn type Fe-Cu polymetallic deposit.Structural geological survey was conducted in the mining area and the ore source-transportation-accumulation-destruction structural system built.In the mining area are superposed sedimentary,intrusive,fold and fault structures.The pre-ore sedimentary structure controls ore source,the intrusive structure,the ore-conductive and accumulative structure.Fold and fault are characterized by multi-activities and fault striking mainly NW-NNW characterized by overlapping of compression and tension torsion and translation activities.The pre-ore Hongniu syncline controls the ore-forming space.Ore bodies all occur in the syncline.The pre-ore Hongshan fault and the sub-structures control the morphology and extension of the ore-bearing geological bodies and play an important role in ore conduction,distribution and accumulation thus control the ore-forming time and space.The syn-mineralization joints and fractures make multiply ore-hosting spaces.The post ore faults and sub-folds modify or destruct ore bodies.