Zijinshan copper-gold deposit is rare epithermal hydrothermal-porphyry copper-gold deposit in the world. The upper of deposit is gold and the lower copper in spatial zonation. Zijinshan Complex massif is one of the most important host rocks of the upper gold deposit. However, the report about the era of Zijinshan Complex massif is poor at present. In order to determine their ages of Zijinshan Complex massif accurately, the three groups of LA-ICP-MS U-Pb dating of situ zircon from Zijinshan Complex massif are tested. Results show that 206Pb/238U weighted average ages of the first Jingmei pluton is (157.9 ± 1.2) Ma (n = 13 , MS WD = 0. 92) , the second Wu-longzi pluton is (149.3 ±1.6) Ma(n = 13,MSWD =1.2) , and the latest Jinlongqiao pluton is (146.3 ±1.6) Ma(n =8,MSWD =0. 39). Zijinshan Complex massif intrusived in late Jurassic, and provide an important new material for epoch of host rock.%本文以赣西西部米级旋回层序研究为基础,依据其平面展布及垂向叠加形式进行三级旋回层序划分,从中二叠世的鸡公岭组至晚二叠世的长兴组共划分出6个三级旋回层序,其时限约5.5 Ma.通过中二叠世米级旋回层序的统计,它可能与地球轨道黄赤交角旋回相当(4万年).该区米级旋回层序相序特征,反映出4次明显的拉张期,即栖霞早期、小江边期、南港期及乐平晚期.依据其空间展布,它们均为陆表海中的裂隙槽或深海沟,表明印支运动作用非常强烈,同时也为钦州造山带“开、合”运动在该区的表现.
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