摘要
1∶25万班戈幅区域地质调查在班戈地区佳琼镇圈定出早白垩世去申拉组火山岩。在充分研究前人资料的基础上,对出露状况较好的棒那拉、恰当早白垩世火山岩进行了野外调研,它们均与中上侏罗统接奴群砂板岩呈断层接触,同时对其进行了LA-ICP-MS锆石U-Pb定年。获得的2组火山岩锆石为(161.3±1.3)Ma、(164.7±1.5)Ma,属于中—晚侏罗世,火山岩具活动大陆边缘火山弧环境特征,可能与班公湖—怒江洋壳俯冲有关。
Volcanic rock of Qushenla Formation in early Cretaceous is delineated by 1 ： 25 million regional geology investigation in Bange district in Jiaqiong town. Based on the full analysis of the previous study, the outcropping in good condition of Bangnala, Qiadang volcanic rocks of early Cretaceous volcanic rocks are investigated, they were contacted with Upper Jurassic Jienu group sand slate, also they were LA-ICP-MS zircon U-Pb dating. Two group volcanic rocks of zircon as 161.3 ＋ 1.3 Ma, 164.7 ＋ detailed ,belong to the middle -late Jurassic. The volcanic rocks with active continental margin volcanic arc environment characteristics, are related with Bangong Lake-Nujiang oceanic crust subduction.
出处
《资源环境与工程》
2015年第6期767-772,共6页
Resources Environment & Engineering
关键词
班—怒结合带
锆石U-PB年龄
地球化学
俯冲消减
Bangong Lake-Nujiang suture zone
Zircon U-Pb age
geochemistry
subducted collision
