作　　者： ; ; ; ; ; ;

机构地区： 中山大学地球科学系

出　　处： 《矿产与地质》 2003年第5期622-626,共5页

摘　　要： 湖南二叠系层状硅质岩石SiO2含量为66.63%～93.66%,平均值为81.10%;TiO2和Al2O3较低,As、Sb富集,稀土总量较低,具有δCe和δEu负异常,与典型的热水沉积硅质岩相似。反映了湖南二叠系层状硅质岩的形成与热水沉积作用有关,并伴有正常沉积的混染,形成环境为弱氧化环境。 The SiO_2 contents of the bedded cherts of the Permian in Hunan are from 66.63～93.66%,the average value of which (81.10%). The cherts are characterized by low content of TiO_2 , Al_2O_3 and total REE, as well as rich As, Sb, negative δCe and δEu, similar to those of hydrothermal sedimentation origin. Geological and geochemical characteristics of the cherts indicate that the rock derived from hydrothermal sedimentation, but influenced by normal chemical sedimentation. The depositional environment of siliceous rocks is low-oxic environment.

关 键 词： 层状硅质岩 成因 地球化学特征 稀土元素 二叠系 湖南

领　　域： [天文地球] [天文地球]