作　　者： ; ; ; ; ; ; (邓雄业）;

机构地区： 中国科学院广州地球化学研究所边缘海地质重点实验室

出　　处： 《大地构造与成矿学》 2008年第2期238-242,共5页

摘　　要： 对冈底斯岩带中部,谢通门唐河电站花岗闪长岩中锆石进行SHRIMP U-Pb定年,结果为45.1±1.7Ma(始新世),岩体的形成时代相当于印度和欧亚两个大陆碰撞的峰期时间,说明谢通门花岗闪长岩为同碰撞花岗岩。 The Xietongmen pluton is located between Xietongmen County and Rikaze City, which belongs to middle part of the Gangdise belt in southern Tibet. The pluton invades in the Carboniferous and Cretaceous in the north; and is covered by the Quaternary sandstones in the south. The pluton is composed mostly of granodiorites and porphyritic biotite granites. Chemically, the granodiorite is peraluminous series. SHRIMP zircon U-Pb dating technique is applied to the granodiorites of the Xietongmen pluton. The result shows that the formation time of the Xietongmen pluton is 45.1 ± 1.7Ma. Most geologists think the Indian-Asian collision began 50Ma ago, so the Xietongmen pluton is syn-collision granodiorite. This result provides a significant evidence for accurately ascertaining the time of the Indian-Asian continental collision.

关 键 词： 定年 碰撞型花岗闪长岩 冈底斯岩带 西藏南部

领　　域： [天文地球] [天文地球]