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在西成铅锌成矿带中 ,硅质岩是主要的含矿岩石之一。硅质岩常呈层状、似层状和透镜状产出 ,具有块状、纹层状、角砾状和多孔状构造。硅质岩中常有热水沉积矿物重晶石、铁白云石和草莓球状黄铁矿出现。在毕家山 -邓家山式热水沉积改造矿床中 ,硅质岩与生物碎屑灰岩 -含炭质生物碎屑灰岩 -硅质岩 -泥质岩组成特征的含矿沉积建造 ,且硅质岩的厚度与铅锌矿化成正比。硅质岩的主成分为 Si O2 ,平均含量为 90 % ,次为 Al2 O3 、Fe2 O3 、Fe O和有机炭等。硅质岩的 K2 O/ Na2 O大多数大于 1,Fe/ Ti平均值为32 .86 ,Al/ (Al+Fe+Mn)值分布在 0 .2～ 0 .6间 ,Th/ U值大于 3.8,有 Ba、As、Hg、Pb、Zn异常 ,属海底热水沉积物 ,硅质岩的稀土元素以总量低、Ce负异常和 Eu正异常为特征 ,在海底热水喷溢沉积形成的矿床中 ,硅质岩与硫化物矿床紧密伴生。
In Xicheng Pb-Zn metallogenic belt, the chert is one of the main ore-bearing rocks. Cherts are often layered, like stratified and lenticular output, with massive, laminar, brecciated and porous structure. Often, hydrothermal sedimentary minerals such as barite, iron dolomite and strawberry globular pyrite appear in cherts. In the Bijiashan-Dengjiashan hydrothermal sedimentary alteration deposit, the cherts and bioclastic limestone-bearing carbonaceous bioclastic limestone-silicalite-argillaceous rocks are characterized by ore-bearing sedimentary deposits and the silicon The thickness of the plagioclase is proportional to Pb-Zn mineralization. The main component of chert is Si O2, with an average content of 90%, followed by Al 2 O 3, Fe 2 O 3, FeO and organic carbon. Most of the K2 O / Na2 O of the cherts are greater than 1, the average value of Fe / Ti is 32.86, the value of Al / (Al + Fe + Mn) is between 0.2-2.6, the value of Th / U is greater than 3.8, there is anomalies of Ba, As, Hg, Pb and Zn. It is a submarine hot water sediment. The rare earth elements of chert are characterized by low total amount, negative Ce anomaly and Eu anomalies, Of the deposits, the chert is closely associated with sulfide deposits.