中文摘要：

本文研究了贵州桑木场地区灯影组硅质岩的主常量、稀土微量元素及硅氧同位素地球化学特征，并对其成因进行了探讨。结果表明，本区硅质岩中SiOz含量高，平均为92．07％；Fe2O3、A12O3、TiO2等相对贫乏，Fe203和A12O3变化范围分别为0．51％～1．12％、0．13％～O．65％，TiOz值多低于检测下限，仅有两个数值为0．01％。微量元素含量普遍较低，但相对富Ba、As、sb、Ag、U，分别是地壳克拉克值的16．75、6．75、7．70、8．69和4．44倍。稀土元素总量低，平均值为11．OO×10；Eu呈明显的负异常，Ce既有正异常，又有负异常。8”si值变化范围为-0．9％oo～-0．1‰，8”O值变化范围为18．5‰～22．40／00。。硅质岩地球化学特征表明其成因为热水沉积，同时混染正常沉积作用。

英文摘要：

The paper studied the geochemical characteristics of main elements, trace elements, REEs and silicon-ox- ygen isotopes of the siliceous rock in the Dengying formation of Sang Muchang, Guizhou province, and discussed its genesis. The results showed that the SiO2 content of the siliceous rock is high with an average content of 92.07% ; Fe2Oa , A120~ and TiO2 contents are relatively low, contents of Fe203 and A1203 are in the range of from 0.51% to 1.12% and from 0.13~ to 0.65%, respectively, while TiO~ contents are below the detection limit in most sam- ples. The trace elements contents are generally low, but Ba, As, Sb, Ag and U contents arel6.75, 6.75, 7.70, 8.69 and 4.44 times higher, respectively, than their crustal Clark values. The total REE content is low with an av- erage of 11.00 X 106; Eu shows a significant negative anomaly and Ce appears both positive and negative anoma- lies. The ~3~Si values are range from -0.9 to -0. 1~0 and the ~180 values are range from 18.5 to 22.4~0. Siliceous rock geochemical features indicate that hot water deposition with ordinary non-hydrothermal sedimentation is the main genesis of the deposit.