摘要
为探讨赣东北景德镇地区双桥山群的沉积时代与物质来源,对该区双桥山群安乐林组地层中发育的一套变火山碎屑凝灰岩夹层进行了年代学、地球化学及锆石Lu-Hf同位素研究。结果显示,该套火山碎屑凝灰岩的岩性主要为英安岩、安山岩,凝灰岩的LA-ICP-MS锆石U-Pb年龄为（809±2）Ma,表明该套岩石形成于新元古代。凝灰岩锆石的Hf同位素组成变化范围较广,其中二阶模式年龄为1426~2313 Ma,主要集中于1.7~2.3 Ga之间,其ε_（Hf）（t）均为负值-2.6^-16.5,t_（DM2）模式年龄远大于U-Pb年龄,表明该组岩石的岩浆来源于元古代地壳物质的再循环。
In order to explore the formation time and provenance of the Shuangqiaoshan Group in Jingdezhen,northeastern Jiangxi Province,we carried out zircon U-Pb geochronological,whole-rock geochemical and Hf isotopic analyses for the low-grade metamorphic volcanic clastic tuff.Petrology and whole-rock geochemistry show that these tuff is mainly composed of dacite and andesite.LA-ICP-MS zircon U-Pb isotope dating results indicate that low-grade metamorphic volcanic clastic tuff was formed at 809±2 Ma,suggesting that the Shuangqiaoshan Group were deposited at Neoproterozoic.Zircon grains have negative ε_（Hf）（t） values from-2.6 to-16.5 and t_（DM2） from 1423 to 2313 Ma,suggests that the parental magmas of these tuff were mainly originated from the melting of Paleo-proterozoic crust.
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2018年第1期103-110,共8页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
公益性行业科研专项(201411035-3)
国家自然科学基金项目(41772069,U1403292)
国家科技支撑计划项目(2015BAB05B04)
中国地质调查局地质调查项目(DD20160053)
