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福建政和地区铜盆庵花岗岩位于政和-大埔断裂带内,与夏山矽卡岩型铅锌矿的形成关系密切,研究程度不高。本文报导了铜盆庵岩体的锆石LA-ICP-MS U-Pb年代学研究结果及其稀土元素组成,岩体中间相锆石的206Pb/238 U加权平均年龄为153.54 Ma±1.8Ma(MSDW=1.8),岩体边缘相锆石的206Pb/238 U加权平均年龄为152.97Ma±0.79Ma(MSDW=3.4),两个样品的锆石的稀土元素配分图均表现为亏损轻稀土、富集重稀土,明显的正Ce异常及负Eu异常,说明其壳源锆石特征。综合区域地质背景认为其形成于古太平洋俯冲下的活动大陆边缘环境,为挤压到伸展过渡构造背景下的产物,并提出夏山铅锌矿的成矿年代与铜盆庵岩体成岩年代相近,成岩成矿关系密切。
The Tongpenan granite in the Zhenghe area of Fujian Province is located in the Zhenghe-Dabu fault zone and is closely related to the formation of the Xiasha skarn-type lead-zinc ore, with a low degree of research. This paper reports the zircon U-Pb zircon dating from the copper deposit at the copper deposit in the Anmian, and the 206Pb / 238 U weighted average age of the mesophase zircons is 153.54 Ma ± 1.8Ma MSDW = 1.8). The 206Pb / 238 U weighted average age of the zircons on the margins of the rock mass is 152.97Ma ± 0.79Ma (MSDW = 3.4). The REE maps of zircons from both samples show depleted LREE, The heavy rare earth elements, obvious positive Ce anomaly and negative Eu anomaly, indicate the characteristics of crust-derived zircon. The comprehensive regional geological background suggests that it formed in active continental marginal environment under the subduction of the Paleo-Pacific Ocean and is a product under the background of extrusion to extensional transitional structure. It is suggested that the mineralization age of Xiasha Pb-Zn deposit is similar to the diagenesis age of the copper basins, Diagenesis and mineralization are closely related.