【摘要】 白银小铁山矿区含矿岩系，前人定为细碧角斑岩系。其中含矿的直接围岩为石英角斑质凝灰岩（π３），经我们研究，该含矿围岩应是分布在韧性剪切带中的一套糜棱岩类，具有明显的变形特征，其原岩为早中寒武世酸性火山岩类。更多还原

【Abstract】 The mineral bearing rock series of Xiaotieshan Mine was named spilite keratophyre sequence by predecessors.The direct mineral bearing adjacent rocks are quartz keratophyric tuffs(π 3).We have approached that the mineral bearing adjacent rocks are a suite of mylonites distributed in a ductile shear zone.The mylonites have obvious deformation features and the protoliths of the mylonites are the lower and middle Cambrian acidic volcanic rocks.更多还原