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研究区地处扬子地台西缘 ,西与松潘甘孜地槽褶皱带以窄小的古火山岩带相隔。在观音崖组、灯影组以及康定群变质杂岩中广泛发育有辉绿岩脉、岩墙。辉绿岩受断裂控制 ,岩脉边部具碎裂结构、糜棱结构、块状构造。岩石蚀变强 ,除少量的斜长石、辉石原生矿物残余外 ,主要由钠长石、角闪石、绿泥石、绿帘石和方解石等变质矿物组成。按岩石化学成分 ,辉绿岩属拉斑系列、钾质类型 ,但按辉石成分 ,也有碱性系列。岩石稀土元素、微量元素表明 ,辉绿岩与茶铺子细碧岩属同源岩浆产物 ,相当于板块碰撞后的次火山活动产物 ,岩浆房深度约为 2 5km。辉绿岩的Au背景值高 ,是Au、Cu矿的矿源层。辉绿岩赋存的断裂是导矿构造 ,辉绿岩浆活动使康定群中的Au活化并随岩浆迁移 ,成矿热液沿断裂上升被辉绿岩阻挡在下盘围岩中成矿。辉绿岩是该区良好的找矿标志。
The research area is located in the western margin of the Yangtze platform, west and Songpan Ganzi geosyncline fold narrow ancient volcanic belt separated. Diabase dikes and dykes are widely developed in the Guanyinya Formation, Dengying Formation, and the Kangdingqu metamorphic complex. Diabase is controlled by faults, with dikes, mylonites and massive structures on the edges of dikes. Except for a small amount of plagioclase and pyroxene primary mineral remnants, the rock alteration is mainly composed of metamorphic minerals such as albite, amphibole, chlorite, epidote and calcite. By petrochemical composition, diabase is a series of pull spots, potash type, but according to pyroxene composition, there are also alkaline series. Rare earth elements and trace elements in rock show that the diabase and the tea shop spargerite belong to the same magma product, which is equivalent to the subvolcanic activity after plate collision. The depth of the magma chamber is about 25 km. Diabase is high in Au background and is a source layer of Au and Cu ore. The diabase-hosted faults are ore-bearing structures. The diabase magma activity activates Au in the Kangding Group and migrates with the magma. The ore-forming hydrothermal fluids rise along the fault and are diabased to block the mineralization of the diabase. Diabase is a good prospecting sign for the area.