斑岩铜矿与陆相火山活动  

PORPHYRY COPPER DEPOSITS AND CONTINENTAL VOLCANISM

作　　者：芮宗瑶[1] 张立生[2] 王龙生[1] 王义天[1] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]成都地质矿产研究所,成都610082

出　　处：《地震地质》2003年第B12期78-87,共10页Seismology and Geology

基　　金：国土资源部大地调项目 (199912 0 0 2 4 6 );国家重点基础研究发展规划项目 (2 0 0 2CB4 12 6 0 10 )资助

摘　　要：斑岩铜矿主要产于聚合板块的上盘 ,是岛弧和活动大陆边缘花岗岩质岩浆 -热液系统 (其中包括火山作用 )演化的产物 ,从斑岩铜矿带与近同期陆相火山岩的关系来看 ,可以归纳为 2种 :一种是斑岩铜矿床或矿田内有同期或稍早期的陆相火山活动 ,例如江西银山、内蒙古乌努格吐山和安徽沙溪等 ;另一种是斑岩铜矿床或矿田内缺少同期陆相火山活动 ,仅见到浅成 -超浅成侵入活动 ,例如江西德兴和西藏玉龙等。斑岩铜矿与陆相火山岩有关的矿床之间具有一定的联系 ,例如有时二者晚期都常发育浊沸石化和硅化 ,常与金等矿化伴生 ,以及常伴随爆破角砾岩和火山口陷落等。环太平洋带、古特提斯带和中亚 -蒙古带为世界斑岩铜矿最发育 ,地质工作最为活跃的地区。中国北部相当于中亚 -蒙古带的一部分 ,东部相当于环太平洋带的一部分 ,西南部相当于特提斯带的一部分 ,集中了许多聚合板块 ,随着洋盆的消减和陆 -陆碰撞的造山作用具有很长的构造 -岩浆 -热液活动的历史(其中包括陆相和海陆交互相火山活动 ) ,故找寻评价斑岩铜矿很有前景。文中重点讨论了东天山、德兴和冈底斯地区同时代的陆相火山活动与斑岩铜矿的关系 ,通过这一讨论 。Porphyry copper deposits are the result of the evolution of granitic magmatism-hydrothermal system (including volcanism) in island arc and on active continent margin, and occur mainly on the upper side of convergent plates. On the basis of the relationship of porphyry copper deposits with penecontemporaneous continental volcanic rocks, porphyry copper deposits may be divided into 2 types: 1) porphyry copper deposits associated with pre-ore or syn-ore continental volcanic rocks, such as the Yinshan deposit in Jiangxi Province, Wunugetu deposit in Inner Mongolia and Shaxi deposit in Anhui Province; 2) porphyry copper deposits associated with hypabyssal and near-surface intrusions rather than syn-ore continental volcanic rocks, such as the Dexing deposit in Jiangxi Province and Yulong deposit in Tibet. Porphyry copper deposits bear a relation to the deposits related to continental volcanic rocks; for example, both of them are suffered from laumontitization and silication, and often associated with Au mineralization and explosion breccia. Porphyry copper deposits were developed mostly in circum-Pacific belt, Paleo-Tethys belt and Central Asia-Mongolian belt. North China lies in the Central Asia-Mongolian belt, east China in the Circum-Pacific belt and southwest China in the Paleo-Tethys belt. Many convergent plates were developed within the three belts. These belts are characterized by a long history of tectonomagmatic-hydrothermal processes including continental and continental-oceanic alternating volcanisms related to oceanic plate subduction and continent-continent collision. Consequently, great potentialities to search for porphyry copper deposits exist in these three belts. This paper focuses mainly on the relationship between the mineralization of porphyry copper deposits and the continental volcanism in the eastern Tianshan, Dexing and Gangdise regions. The results of this study may provide scientific basis for the prospecting and assessment of porphyry copper deposits.

关 键 词：斑岩铜矿 陆相火山活动 聚合板块 浊沸石化 硅化 

分 类 号：P317.4[天文地球—固体地球物理学]