摘要
西藏班公湖-怒江缝合带北缘多龙矿集区是青藏高原新近发现的具有超大型远景的、典型的富金斑岩型铜矿集区,其成岩成矿地质背景是解决班公湖-怒江洋构造演化的关键问题之一。近年来的区域地质调查研究发现,多龙矿集区南侧出露岩墙岭蛇绿岩残片,应该是班公湖-怒江蛇绿岩带的重要组成部分。岩墙岭蛇绿岩主要由席状岩墙群、枕状玄武岩和硅质岩组成,整体呈棱形或透镜体状断续分布于侏罗系复理石沉积内,构成典型的网结状构造。糜棱岩普遍发育在岩墙岭蛇绿岩和围岩的接触部位。综合前人研究成果,初步认为多龙矿集区早白垩世成岩成矿作用应该形成于增生楔之上伸展拉张的构造环境。岩墙岭蛇绿岩的发现和确定进一步约束了多龙矿集区成岩成矿地质背景,同时为班公湖-怒江缝合带的延伸及其构造演化的研究提供了新的线索。
The Duolong ore concentration area, located on the northern margin of Bangong Co-Nujiang River suture zone, possesses giant prospective typical gold-rich porphyry copper deposits in Tibet. The petrogenesis of the intrusions and the ore-forming processes of the Duolong ore concentration area are the key points for solving the tectonic evolution of Bangong Co-Nujiang River Ocean. Recently, Yanqiang Ling ophiolite belonging to Bangong Co-Nujiang River ophiolite belt was discovered on the southern side of the Duolong ore concentration area. Yanqiang Ling ophiolite which was tectonically emplaced in the Jurassic flysch sediments mainly consists of sheeted dykes, pillow basalt and silica rock. Mylonite is widely developed in the contact area between the country rock and the Yanqiang Ling ophiolite. Combined with previous studies, the authors hold that the Duolong ore concentration area developed on the basis of accretionary wedge and was in extensional setting during the Early Cretaceous. The discovery and determination of Yanqiang Ling ophiolite further constraint the geological setting of the Duolong ore concentration area and provide a newclue for extension and study of Bangong Co-Nujiang River suture zone.
出处
《地质通报》
CAS
CSCD
北大核心
2016年第5期642-647,共6页
Geological Bulletin of China
基金
国家自然科学基金项目(批准号:41272240)
中国地质调查局项目(编号:12120113036700)
中国地质科学院地质研究所基本科研业务费项目(编号:J1524)
关键词
青藏高原
班公湖-怒江缝合带
多龙矿集区
岩墙岭蛇绿岩
席状岩墙群
Tibetan Plateau
Bangong Co-Nujiang River suture zone
Duolong ore concentration area
Yanqiang Ling ophiolite
sheeted dykes
