湖南大庸慈利一带下寒武统黑色页岩中海底喷流沉积硅岩的地质特征  

The Geological Characteristics of Sea floor Exhalation Sedimentary Chert in Lower Cambrian Black Shales in Dayong Cili Area, Hunan Province

作　　者：李有禹[1] 

机构地区：[1]湘潭矿业学院

出　　处：《岩石学报》1997年第1期121-126,共6页Acta Petrologica Sinica

基　　金：煤炭科学基金

摘　　要：湘西北大庸慈利一带下寒武统黑色页岩中的硅岩，分布上受深断裂控制，具多孔状构造，微量元素Ｓｅ、Ａｓ、Ｂａ含量较高，Ａｌ／（Ａｌ＋Ｆｅ＋Ｍｎ）比值为０．１５～０．３２，稀土元素ΣＲＥＥ含量大于围岩的数倍，Ｃｅ亏损，δ１８Ｏ（对ＳＭＯＷ）值为１７．６２‰～２２．９１‰。这些特征表明，该硅岩是一种典型的喷流岩。The distribution of chert in Lower Cambrian black shales in Dayong Cili area, Hunan province, is controlled by a deep seated fracture. The chert has a sponpy structure, higher contents of trace element Se, As, Ba and a ratio of Al/(Al+Fe+Mn) between 0.15～0.32. Its rare earth elements ΣREE are several times richer than those of country rock, with deficient element Ce. The value of oxygen isotope δ 18 O ranges from 17.62‰ to 22.91‰. All of these characteristics show that the chert in this area is a kind of typical exhalilative rock, and constitute the Ni Mo multimetallic host rock system in Northwestern Hunan.

关 键 词：下寒武统 黑色页岩 层状硅岩 喷流成因 沉积岩 

分 类 号：P588.311[天文地球—岩石学] P588.2[天文地球—地质学]