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银山矿区次火山岩主要可分为三类 ,1石英斑岩 2英安斑岩 3安山玢岩 ,它们均属于一套高钾钙碱性的中酸性花岗岩系列。矿区次火山岩中 ,Cu、Ag、Pb、Zn等成矿元素均高出同类岩性克拉克值 1倍以上 ,表明次火山岩与矿床形成关系密切。岩石地球化学特征表明 :矿区次火山岩属幔壳混合源 ,它们分别形成于幔源花岗岩区 ,板块碰撞前消减区 (消减的活动板块边缘 )和板块碰撞后隆起花岗岩区 ,这说明与矿床有关的火山活动发生在成熟的陆壳构造之上受太平洋板块向陆壳板块俯冲影响而形成的活动大陆边缘。成矿时代为燕山早期晚阶段
The subvolcanic rocks in the Yinshan ore district can be divided into three types, one quartz porphyry, 2 amphibolite 3 andesite, all belong to a series of high-K calc-alkaline medium-acid granite series. In the sub-volcanic rocks, Cu, Ag, Pb, Zn and other ore-forming elements are more than 1 times higher than the Clay value of the same lithology, indicating that the subvolcanic rock is closely related to the ore deposit. The geochemical characteristics of the rocks show that the secondary volcanic rocks in the ore district are mantle-crust mixed sources, which are respectively formed in the mantle-derived granite area, the subduction zone before the collision of the plate (the edge of the abated movable plate) and the granite area after the plate collision, indicating that the ore- Volcanic activity takes place on mature continental crust formations above the active continental margin formed by the subduction of the Pacific plate to the continental shelf. The metallogenic epoch is the late Yanshanian period