皖东南黄片麻岩的锆石U-Pb年龄

U-Pb dating of zircon from gneiss at Nanhuang in East Anhui.

在皖东嘉山南黄地区新元古代张八岭岩群之下 ,隐伏一套角闪岩相的 TTG质片麻岩类。单颗锆石 U - Pb法年龄测定得到其不一致线上交点年龄为 2 493± 19Ma,代表了片麻岩原岩的形成年龄。这是扬子陆块北东缘首次发现的新太古代基底 。

There is a suboutcrop of amphibolite facies TTG gneiss overlain by Neoproterozoic Zhangbaling Group at Nanhuang region in Jiashan, East Anhui. U Pb dating was carried out for the single grains of zircon from the gneiss. The results show an age of 2493±19Ma for the upper intersect of discordia with concordia, which is interpreted to represent the formation age of the Nanhuang gneiss. In this regard, there is the Neoarchean rock in the northeastern margin of the Yangtze plate, doucmenting the widespread presence of Neoarchean to Paleoproterozoic basements in the northern margin of the Yangtze plate.