石咀子铜矿地质特征及“互层带”赋矿解译

摘要

石咀子铜矿赋存于上石炭统石咀子组的中部层位互层带中，成矿受燕山早期及先期复活的北西向上鹿—六间房断裂（挤压带）与南北向挤压构造、北东向断裂构造之交汇部位（构造开阔带）控制，矿体在空间上与燕山早期浅成脉岩石英斑岩关系密切。铜矿是幔汁（即地幔流体）衍生的碱交代热液成因，燕山早期，碱交代热液伴随着石英斑岩等岩墙的贯入而沿岩墙上涌、交代、萃取途经岩石（尤其是深部矿源层中的矿质），于互层带中沉淀聚集成矿。互层带是铜等多金属矿质沉淀聚集的最佳物理化学区间，其赋存矿体与其是否提供矿质没有必然的联系。互层带赋矿的深部机制：互层带的背斜轴部（南北向挤压带）处于地幔软流体上凸部的上方，以致互层带是碱交代热液上涌的直达区域。%The origin of copper deposit is that mantle ichor the mantle fluids derived from the alkaline metasomatic hydrothermal solution, the alkaline metasomatic hydrothermal solution with penetration of quartz porphyry dikes, upwelling along the dike, replacing, and extracting via the rocks (especially the minerals in deep ore source layer) must have settled, assembled and mineralized in the interbed zone in early Yanshanian. The interbed zone is the best physical and chemical space for the aggregation of copper and other metals, the occurrence of ore bodies was not necessarily related to whether or not to provide the minerals. Deep mechanism about the interbed zone ore-hosting is the mantle asthenospheric“bump”over the anticlinal axis of the interbed zone (North South compression zone), so that the interbed zone is the direct region of upwelling the alkaline metasomatic hydrothermal solution.