中文摘要：

赣南大埠岩体缺乏精确的同位素定年证据。选择大埠岩体西南部的中粗粒黑云母二长花岗岩进行了锆石激光剥蚀-多接收器电感耦合等离子体质谱（LA—MC—ICPMS）U—Pb定年。研究结果显示，岩体中锆石的唧b／238U加权平均年龄为（423．3±3．5）Ma，表明该岩体形成于志留纪，对应加里东晚期岩浆热事件。加里东期花岗岩的形成与扬子陆块和华夏陆块的拼合有关，反映南岭加里东期岩浆活动的一个重要阶段。而703．2Ma的残留锆石年龄的发现,说明大埠岩体在成岩过程中至少有新元古代地层加入。

英文摘要：

Dabu pluton in the south of Jiangxi is lack of accurate isotope dating evidence. The medium-coarse-grained biotite monzogranite from south-west of Dabu pluton was used for zircon laser ablation-multiple collector inductively coupled plasma mass spectrometry（LA-MC-ICPMS）U-Pb dating. The results show that the weighted average ^206Pb/^238U age of the zircon in pluton is（423.3±3.5）Ma, which means the pluton forms in Silurian and corresponds to the magmatic activity in late Caledonian. The formation of the Caledonian granite is relative to the collision of Yangtze landmass and Cathaysia landmass, it reflects an important phase of the Nanling Caledonian magmation. The discoveries of the 703.2Ma age of remain zircon indicate that Neoproterozoic strata was involved in the diagenesis of Dabu intrusions.