广西钦州地区那丽花岗岩LA-ICP-MS锆石U-Pb定年及其地质意义

LA-ICP-MS zircon U-Pb age of the Nali granite in Qinzhou area of southern Guangxi and its geological significance

摘要: 位于广西南部钦州地区的那丽岩体是华南地区（除海南岛外）报道的、具精确同位素年龄的海西期花岗岩岩体，LA-ICP-MS锆石U-Pb定年结果显示其形成时代为262Ma。二叠纪时期，羌塘-中缅Sibumasu地块与印支地块碰撞拼合，导致华南陆块俯冲于印支陆块之下，那丽花岗岩可能形成于这种俯冲作用的较晚阶段——弧后伸展环境。

Abstract: This paper reported the recent discovery of Hercynian granite at Nali of Qinzhou in Guangxi. The Nali granitic body has crystallization ages of 262Ma obtained by LA-ICP-MS zircon U-Pb method. In Permian period, the collision between Qiangtang-Sibumasu block and Indochina block resulted in the thrusting of South China block beneath Indochina block. The Nali granites were generated at the late stage of this subduction, probably in a back-arc extension setting.