摘要
本文采用锆石激光剥蚀法(LA-ICP-MS)对云南景洪南联山岩体闪长岩体进行了锆石U-Pb年龄测定,获得了两个年龄值300.0±2.6Ma和305.7±3.7Ma(1σ)。这一年龄体现了滇西地区古特提斯向东俯冲之岛弧岩浆活动的时代,说明滇西古特提斯在晚石炭世就开始了俯冲事件。结合澜沧江断裂带景洪-半坡一带相似的基性岩体年龄值,表明古特提斯洋俯冲开始于景洪一带,然后向北延伸。
In this paper, the zircon U-Pb dating of Nanlianshan rock body in Jinghong, Yunnan is by the zircon laser ablation method （LA-ICP-MS） , resulted in 300.0 ±2.6Ma and 305.7 ± 3.7Ma, which show the magmation age of island arc of eastward subduction of Tethys in W Yunnan and indicate that the subduction of Tethys in W Yunnan started in Late Carboniferous. In combination with the age of similar basic rock body in Jinghong-Banpo area of Lancangjiang fault zone, we think that the subduction of Tethys started in Jinghong area, then developed northwards.
出处
《云南地质》
2016年第2期131-136,共6页
Yunnan Geology
基金
中国地质调查局
1:25万澜沧县
景洪市
勐海县
勐腊县四幅区域地质调查修测(项目编号:1212011120593)
