新疆卡拉麦里蛇绿岩带中硅质岩的放射虫化石  

Late Devonian-Early Carboniferous Radiolarian Fossils from Siliceous Rocks of the Kelameili Ophiolite, Xinjiang

作　　者：舒良树[1] 王玉净[2] 

机构地区：[1]南京大学地球科学系,210093 [2]中国科学院南京地质古生物研究所,210008

出　　处：《地质论评》2003年第4期408-412,T002,共6页Geological Review

基　　金：国家973西部项目(编号2001CB409804);国家自然科学基金(编号40172004)

摘　　要：新疆卡拉麦里构造带在奇台县南明水地区可划分为三个岩石-构造单元:①北带,由中泥盆世复理石组成;②南带,由中泥盆世—早石炭世沉积岩-火山质碎屑岩组成;③蛇绿岩带。三者之间均为断裂接触。蛇绿岩套上部单元的红色硅质岩中发现丰富的放射虫化石,经鉴定,其时代确定为晚泥盆世法门期—早石炭世杜内期,代表卡拉麦里蛇绿岩形成的晚期年龄。The Kelameili ophiolite zone is located on the northern margin of the Tianshan orogenic belt, representing a suture between the Siberian and the Tarim continental blocks. The Nanmingshui area is a typical tectonic segment with continuous geologic outcrops and distinct petrological features. Based on the 1 : 50,000 mapping in the Nanmingshui area, the Kelameili zone can be divided into three petrotectonic units: the northern sub-zone consisting of Middle Devonian sedimentary rocks, the southern sub-zone consisting of Middle Devonian-Early Carboniferous sedimentary rocks and volcanoclastic rocks, and the ophiolitic melange sub-zone. These three sub-zones are divided each other by a fault. Red siliceous rocks, which overlie the basaltic layers of the Nanmingshui ophiolitic melange zone, contain rich radiolarians. The radiolarians are identified as of the Late Devonian Famenian in age, representing the age of the late stage forming the Kelameili ophiolite. From that, the closure time of the Tianshan Ocean should be no earlier than the Late Devonian.

关 键 词：新疆 卡拉麦里蛇绿岩带 硅质岩 放射虫化石 

分 类 号：Q915[天文地球—古生物学与地层学]