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对北祁连加里东招皱带中白银矿田成矿蚀变岩的研究表明，蚀变岩筒具有明显的分带性.中心部位是绿泥石化带，以绿泥石＋石英＋黄铁矿组合为特征；其外是绢云母硅化带，以绢云母＋石英＋黄铁矿组合为特征，最外则是未蚀变带或弱蚀变带．岩石化学上，随着蚀变作用增强，MgO、K2O、FeO增加，而Na2O降低；白银矿田成矿系列中由Cu－Zn型到Cu－Pb－Zn型、Pb－Zn－Cu型矿床，绿泥石中MgO、SIO：有降低趋势．产于火山机构不同部位的火山口Cu－Zn型矿床（如折腰山）和火山斜坡Pb－Zn－Cu（如小铁山）矿床蚀变岩筒有所不同：折腰山蚀变岩筒平面上呈椭圆形，具明显的水平分带；小铁山矿床则呈NW-SE延伸的板柱体，上都有重晶石化，向深部绿泥石化用加强，显示了较明显的垂直分带．蚀变岩筒的存在，首先是海底热液对流循环成矿作用的直接证据，成为白银块状硫化物矿床新的成矿模式和理论研究的奠基石．更为重要的是，它可以成为寻找盲矿的主要标志（施林道，1986）．
The study on the mineralized alteration rocks in the Baiyin orefield in the Caledonian crinkling zone in the North Qilian shows that the altered rock has obvious zonation and the central part is a chlorite zone with chlorite + quartz + yellow iron Ore assemblage. The outer zone is sericite silicified zone characterized by sericite + quartz + pyrite assemblages, with the exception of unmodified zones or weakly altered zones. In the petrochemistry, the MgO, K2O and FeO increase with the increase of alteration, while the Na2O decreases. The Cu-Zn to Cu-Pb-Zn and Pb-Zn- Chlorite in MgO, SIO: there is a downward trend. The alteration rock cores of the Cu-Zn deposits (such as the fold mountain) and the Pb-Zn-Cu deposits (such as the Xiaoshan) of the volcanic slopes produced in different parts of the volcano are different: Oval shape, with obvious horizontal zoning; Xiaodianshan deposit NW-SE extension of the plate cylinder, there are barite, to strengthen the deep chloritization, showing a more obvious vertical zoning. The alteration of the rock tube is first of all directly evidenced by the hydrothermal convection and mineralization in the seafloor, and becomes the cornerstone of the new mineralization model and theoretical study of the silver massive sulfide deposit. More importantly, it can be a major sign of finding blind mines (Shihlin Road, 1986).