碰撞造山作用期后伸展体制下的成矿作用——以小秦岭金矿集中区为例  

Mineralization in the post-collisional orogenic extensional regime:A case study of the Xiaoqinling gold deposit clustering area

作　　者：王义天[1] 毛景文[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037

出　　处：《地质通报》2002年第8期562-566,共5页Geological Bulletin of China

基　　金：国家重点基础研究发展规划(G1999043211)项目资助。

摘　　要：小秦岭在中生代期间经历了强烈的构造活动变迁,区域构造体制由挤压向伸展过渡,并最终在伸展体制下于晚燕山期形成小秦岭变质核杂岩,其深部过程为中国东部大陆岩石圈拆沉作用而引起软流圈物质上涌。小秦岭是中国重要的金矿集中区,主要产出3种类型的金矿床,其空间分布规律和成矿时代特征表明,本区金的成矿作用奏始于碰撞造山作用的后期,主成矿期发生在造山作用期后以伸展体制为主导的晚燕山期。碰撞造山带在造山作用期后常常发育伸展构造,伸展体制下的变形变质演化和多源流体活动使大规模成矿作用成为可能。As a component part of the Qinling oro gen,the Xiaoqinling area,located on the south mar-gin of the North China plate,underwent strong tectonic changes during the Mesozoic.The regional tec-tonic regime changed from compressional to extensional,and finally the Xiaoqinling metamorphic core complex originated in the extensional regime in the late Yanshanian,whose deep process was the up-welling of asthenospheric material caused by the delamination of the continental lithosphere in eastern Chi-na.The Xiaoqinling area is an important gold deposit clustering area in China,and three types of gold deposits occur in this area.The spatial distribution characteristics and metallogenic ages of gold deposits in-dicate that gold mineralization was initiated in the late stage of collisional orogeny and that the main met-allogenic epoch took place in the late Yanshanian when the extensional regime predominated.Extensional tectonics often developed in the collisional orogenic belt during post-collisional orogeny,and the defor-mation -metamorphism evolution and the activity of multi -source fluids controlled by the extensional regime can result in large-scale mineralization.

关 键 词：碰撞造山作用 成矿作用 造山带 伸展体制 成矿作用 金矿床 空间分布 成矿时代 

分 类 号：P618.51[天文地球—矿床学]