江西高陂地区沙坝黄组火山岩夹层地球化学、锆石U-Pb年龄及其地质意义  

Geochemistry,Zircon U-Pb Ages and Geological Significance of Volcanic Interbedded Rocks of the Shabahuang Formation in the Gaopi Area,Jiangxi

作　　者：李凯 杨细浩 李业兴 楼法生 苏莱曼 LI Kai;YANG Xihao;LI Yexing;LOU Fasheng;SU Laiman(Jiangxi Institute of Geological Prospecting and Mineral Resource for Nonferrous Metal,Nanchang 330030,China;Jiangxi Institute of Geological Survey and Exploration,Nanchang 330009,China)

机构地区：[1]江西有色地质矿产勘查开发院,江西南昌330030 [2]江西省地质调查勘查院,江西南昌330009

出　　处：《东华理工大学学报(自然科学版)》2025年第1期30-39,共10页Journal of East China University of Technology(Natural Science)

基　　金：中国地质调查局国家大调查项目(12120114024401)。

摘　　要：为查明南华系沙坝黄组的沉积环境及时代,对江西高陂地区新发现的火山岩开展野外地质调查、薄片鉴定、岩石地球化学、锆石U-Pb同位素年代学等研究。结果显示,新发现的变质酸性火山岩锆石LA ICP MS U-Pb测定年龄为(727±5)Ma,确定其形成时代为南华纪早世,具有高硅、富碱、低镁、低磷、贫钛、过铝质等特征,富集Rb、K、Ba、Zr、Hf等大离子亲石元素,亏损Nb、Ta、Ti等高场强元素,轻重稀土分异明显,中等负Eu异常,具有陆相火山岛弧的地球化学特征,暗示其可能形成于造山晚期岛弧海盆拉张环境。In order to find out the sedimentary environment and age of the Shabahuang Formation of the Nanhua System,field geological investigation,thin section identification,lithogeochemistry,and zircon U-Pb isotopic chronology were carried out on newly discovered volcanic rocks in the Gaopi area,Jiangxi.LA-ICP-MS U-Pb dat-ing of zircon from the newly discovered metamorphic acidic volcanic rocks is(727±5)Ma,and the age of its for-mation is determined to be the Early Nanhua,with the characteristics of high silicon,rich alkali,low magnesium,low phosphorus,poor titanium and peraluminous.It is rich in Rb,K,Ba,Zr,Hf and deficient in high field strength elements such as Nb,Ta,Ti.The heavy and light rare earth elements are obviously different,and the medium negative Eu anomaly has the geochemistry characteristics of continental volcanic island arc,which sug-gests that it may have been formed in the extension environment of island arc basin during the late orogenic peri-od.

关 键 词：锆石U-PB年龄 岩石地球化学 变质火山岩 沙坝黄组 高陂地区 

分 类 号：P588[天文地球—岩石学] P597[天文地球—地质学]