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硅岩建造是西秦岭拉尔玛—邛莫层控金矿床的含矿岩系。含矿层状硅岩呈块状、条带状、层纹状、多孔状和同生角砾状等，单层厚度一般为３０ｍ～２００ｍ。主要成分ＳｉＯ２平均含量高达９５．３０％，其余为ＦｅＯ、Ｆｅ２Ｏ３和有机炭等。硅岩的Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）比值低于０．３５（平均０．１５３）。硅岩中微量元素十分丰富，不仅含具基性、超基性特征的元素群（如Ｃｕ、Ｃｒ、Ｐｔ、Ｐｄ、Ｏｓ等），而且含具酸性特征的元素群（如Ｗ、Ｍｏ、Ｕ等）。硅岩中稀土以总量低（３２．９×１０－６～１００×１０－６）、δＣｅ亏损为特征。经北美页岩标准化后，稀土含量随原子序数的增大而增大。硅岩的δ１８Ｏ值为１７．６０‰～２３．２４‰，其形成温度约为７０℃～１１８℃。硅岩的δ３０Ｓｉ值主要在＋０．４‰～＋０．８‰之间。硅岩的上述特点均显示其与喷流沉积作用有关。喷流沉积作用不仅形成了特殊的硅岩建造，而且也使金等元素在硅岩建造中发生了明显的聚集。
The formation of silicon rocks is the ore-bearing rock series of the Laerma-Kuimo stratified gold deposit in the West Qinling. Ore-bearing layered silicites are massive, banded, layered, porous and conglomerate-like, monolayer thickness is generally 30m ~ 200m. The main component of SiO2 average content of up to 95.30%, the rest of FeO, Fe2O3 and organic carbon. The ratio of Al / (Al + Fe + Mn) of silicon rocks is less than 0.35 (average 0.153). The trace elements in the siliciclastic rocks are very rich. They contain not only basic and ultrabasic elements (Cu, Cr, Pt, Pd, Os, etc.) but also acidic elements such as W, Mo, U Wait). The rare earths in silicon rocks are characterized by low total amount (32.9 × 10-6 ~ 100 × 10-6) and δCe loss. After the standardization of North American shales, the content of rare earth increases with the increase of atomic number. The δ18O value of silicite is 17.60 ‰ ~ 23.24 ‰, and the formation temperature is about 70 ℃ ~ 118 ℃. The δ30Si value of silicon rocks is mainly between + 0.4 ‰ and + 0.8 ‰. The above characteristics of silicon rocks show that they are related to jet deposition. Jet deposition not only formed a special silicon rock formation, but also gold and other elements in the silicon rock in the construction of a significant accumulation.