甘肃北山火石山地区早古生代蛇绿混杂岩的发现及其地质意义  

The Discovery and Geological Significance of an Early Paleozoic Ophiolite Mélange Belt in the Huoshishan Part of Beishan Mountain,Gansu Province,China

作　　者：王立社[1] 杨建国[2] 谢春林[2] 王育习[2] 

机构地区：[1]西北大学地质学系,陕西西安710069 [2]西安地质矿产研究所,陕西西安710054

出　　处：《现代地质》2007年第3期451-456,共6页Geoscience

基　　金：中国地质调查局战略性矿产远景调查项目(K47E015001;K47E016001)

摘　　要：在甘肃北山火石山地区新发现了蛇绿混杂岩,该混杂岩由蛇绿岩岩块和混杂基质组成。蛇绿岩块有纯橄岩、辉石橄榄岩、辉石岩、辉长岩、玄武岩及硅质岩等。基质为志留系中上统公婆泉群,主要是一套变凝灰质砂岩夹碳酸盐岩和少量安山岩。野外调查及室内鉴定结果显示蛇绿岩岩块和基质遭受了较强的变质变形。火石山蛇绿混杂岩位于红柳河、牛圈子蛇绿岩之间,且该蛇绿岩地球化学特征显示其同红柳河蛇绿岩相似,因此认为红柳河—牛圈子蛇绿混杂岩是通过火石山相连接。火石山蛇绿混杂岩的发现对研究该带洋陆时空演化提供了新的线索,对北山古生代构造背景研究具有重要意义。This paper aims to introduce the strange Mountains. The authors discovered the ophiolite ophiolite mélange of the Huoshishan area of Beishan mrlange in the fieldwork in 2006, which are composed of exotic blocks and schiefers such as serpentinization peridotite schiefers, pyroxenite schiefers, basalt schiefers, siliceous-rocks and matrix. The matrix is located in Gongpoquan Group, which is made up of lots of metamorphic tuffaceous sandstones, little andesite and carbonate. Most of exotic blocks and matrix have metamorphosed. The Huoshishan ophiolite mélange occurs between the Hongliuhe and Niujuanzi ophiolite mélange, and the petrochemical and geochemical characteristics are similar to that of Honliuhe. Consequently, this research indicates that Huoshishan ophiolite mélange perhaps belong to Hongliuhe-Niujuanzi ophiolite mélange belt. The discovery of ophiolite mélange is important for study of the Paleozoic tectonic background of Beishan area

关 键 词：红柳河-牛圈子 火石山 蛇绿混杂岩 北山 

分 类 号：P588.1[天文地球—岩石学]