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班公湖-怒江结合带横亘于青藏高原中部,俯冲方向和俯冲时间是目前人们争论的焦点之一。研究区位于班公湖-怒江缝合带中段,处于木嘎岗日雪山南麓,赛布措以北,构造复杂、岩浆活动强烈、成矿条件较为有利。高堡约石英闪长岩U-Pb锆石年代学及地球化学特征研究为班公湖-怒江洋北向俯冲期提供了年代学依据,还原了中侏罗世班公湖-怒江缝合带中段构造演化过程中的岩浆作用响应。研究结果显示,高堡约石英闪长岩锆石206Pb/238U加权平均年龄为154.46±0.71 Ma(MSWD=0.93),
The Bangong Lake-Nujiang junction belt lies in the central part of the Qinghai-Tibet Plateau, with subduction direction and subduction time being the focus of debate. The study area is located in the middle part of Bangong Lake-Nujiang suture zone, at the southern foot of Mount Hagasan in Mugagang, north of Cyclocarb, with complex structure and strong magmatic activity with favorable metallogenic conditions. The study on the geochronology and geochemical characteristics of the U-Pb zircons from the Quartet-diorite in the Gaobeao area provided a chronological evidence for the northward subduction of the Bangong-Nujiang Ocean, restoring the middle Jurassic Bangonghu-Nujiang suture Magmatic response during evolution. The results show that the weighted average age of 206Pb / 238U zircons from the Qiangpu quartzite is 154.46 ± 0.71 Ma (MSWD = 0.93)