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长坑矿床的金、银矿化与硅质岩关系最为密切，角砾状硅质岩矿体具层控和断裂控制双重特点。含矿硅质岩的ＳｉＯ２含量为７３％～９２％，其平均值（８８％）与海底热液燧石相近，但硅质金矿石的ＴｉＯ２、Ａｌ２Ｏ３、ＴＦｅ、ＣａＯ、Ｋ２Ｏ和银矿石的ＣａＯ、ＦｅＯ含量平均值明显高于热水沉积硅质岩；在ＡｌＦｅＭｎ成分三角图上，含矿硅质岩在水成区和热液区均有分布。虽然矿化硅质岩的稀土成分具海底热水沉积岩的特点，即总量较低，具Ｃｅ负异常，但其模式曲线与围岩相似。硅质矿石相对富Ｆｅ，贫Ｃｕ、Ｃｏ、Ｎｉ，过渡元素配分模式继承了围岩的特点。结合硅质矿体的地质产状、矿化年龄与成矿流体来源，认为硅质矿石主要形成于热液对围岩和裂隙的交代、充填作用，但不排除早期热水沉积硅质岩存在的可能性。
The gold and silver mineralization of Changkeng deposit is the most closely related to silicalite, and the brecciated silicalite ore body has dual characteristics of layer control and fault control. The SiO2 content of ore-bearing cherts is 73% -92%, and the average value (88%) is similar to the seabed hydrofluorite. However, the contents of TiO2, Al2O3, TFe, CaO and K2O in siliceous gold ore and CaO, The average value of FeO is obviously higher than that of hydrothermal sedimentary chert; on the triangle diagram of AlFeMn composition, the ore-bearing chert is distributed in both water-forming and hydrothermal zones. Although the composition of the rare earths of mineralized cherts is characterized by submarine hydrothermal sedimentary rocks, ie, lower total amount and negative Ce, the model curves are similar to those of the surrounding rocks. The siliceous ore is relatively rich in Fe and poor in Cu, Co, Ni. The transitional elemental allocation mode inherits the characteristics of the surrounding rock. Combined with the geological occurrence, mineralization age and source of ore-forming fluid, the authors believe that the silicic ores mainly formed in the replacement and filling of hydrothermal rocks and fissures but did not rule out the existence of early hydrothermal-sedimentary chert The possibility of.