甘肃北山地区基本构造格局和成矿系列特征  

Basic tectonic framework and features of metallogenic series in Beishan area,Gansu Province

作　　者：杨建国[1] 谢春林[1] 王小红[1] 谢燮[1] 王磊[1] 王静平[1] 

机构地区：[1]中国地质调查局西安地质调查中心,陕西西安710054

出　　处：《地质通报》2012年第2期422-438,共17页Geological Bulletin of China

基　　金：中国地质调查局战略性矿产远景调查专项<甘肃营毛沱地区矿产远景调查>和地质矿产调查专项<甘肃北山营毛沱-玉石山地区铁铜多金属矿产调查>(编号:1212011085090)

摘　　要：甘肃北山地区并不存在具分割洋-陆板块构造意义的缝合带或蛇绿岩带,主体由东天山和塔里木两大古陆系统构成。两大古陆系统的碰撞拼合带或界线大体位于方山口—黑山—碱泉子一线,以北归属东天山古陆系统,以南归属于塔里木古陆系统。按其内的地层时代、沉积建造、岩浆作用、地壳结构等特征,可将东天山古陆系统从北往南划分为北山岛弧带、北山(白山)晚古生代弧后盆地裂陷(谷)带和北山中央古陆断隆带3个Ⅱ级结构单元,空间上三者构成一个从岛弧—弧后盆地—前陆基底带的洋-陆过渡性的地壳结构。南侧的塔里木古陆系统则经历了初始陆核向成熟陆壳发展演化的地史过程,按不同地段的地壳结构和构造作用特征将其划分为(从北往南)塔里木古陆陆缘早古生代裂陷带、红柳园-大奇山-天仓古生代多旋回裂谷带和塔里木前陆基底带3个Ⅱ级构造单元。在此基础上,根据相关的成矿响应特征综述了不同构造单元的成矿系列。In Beishan area,the suture zone or ophiolite belt that represents the dividing of ocean-continent tectonic plate is nonexistent,and the main body is composed of East Tianshan and Tarim old land systems.Their collision boundary is generally located along Fangshankou-Heishan-Jianquanzi line;the area north of this line belongs to Dongtianshan old land system,and that south of this line is assigned to Tarim old land system.According to stratigraphic age,sedimentary formation,magmatism and crustal structure,the Dongtianshan old land system is divided into three second-grade tectonic units from north to south,i.e.,Beishan island arc belt,Late Paleozoic back-arc rift zone and fault-uplift zone of central old land.They spatially make up an ocean-continent transitional framework of island arc-back-arc basin-foreland basement.The southern Tarim old land system experienced the evolution from the original continental nucleus to mature continental crust.Based on characteristics of crustal structure and tectonism,the authors also divided this old land system into three second-grade tectonic units from north to south,namely Early Paleozoic depression zone of Tarim old land margin,Hongliuyuan-Daqishan-Tiancang Paleozoic multicyclic rift zone and Tarim old land basement.Besides,the metallogenic series of different tectonic units are summarized in this paper.

关 键 词：甘肃北山 构造格局 构造单元划分 古陆系统归属 成矿系列特征 

分 类 号：P54[天文地球—构造地质学] P611[天文地球—地质学]