粤东宝山嶂地区早白垩世花岗斑岩锆石年代学、地球化学特征及其地质意义  

Zircon Choronology,and Geochemical Characteristics and Their Geological Significance of the Early Cretaceous Granite Porphyry in the Baoshanzhang Area,Eastern Guangdong

作　　者：陈南通 李媛 胡昆 何翔 叶升明 李锐 尼玛央金 Chen Nantong;Li Yuan;Hu Kun;He Xiang;Ye Shengming;Li Rui;Nimayangjin(School of Earth Science,East China University of Technology,Nanchang,Jiangxi,330000,China;Guangdong Geological Survey Institute,Guangzhou,Guangdong,510080,China)

机构地区：[1]东华理工大学地球科学学院,江西南昌330000 [2]广东省地质调查院,广东广州510080

出　　处：《化工矿产地质》2025年第1期11-20,共10页Geology of Chemical Minerals

基　　金：广东省地质勘查与城市地质专项广东东源地区1∶5万区域地质调查(编号:2022-17);广东1∶5万双江圩、义合圩、河源县、柏埔圩幅区域地质调查(编号:2023-16);广东1∶5万蓝塘、观音阁幅区域地质调查(编号:2023-19)。

摘　　要：粤东宝山嶂地区位于华南大陆边缘东南沿海火山-侵入岩带的西南端。本文对该地区出露的花岗斑岩进行了LA-ICP-MS锆石U-Pb年龄、微量元素、Lu-Hf同位素的地球化学研究,以揭示其成岩时代,并探讨锆石成因和岩浆源区。锆石U-Pb定年显示宝山嶂花岗斑岩加权平均年龄为108.71±0.83Ma(MSWD=3.5,n=22),属早白垩世晚期岩浆产物;通过锆石的Th/U含量、明显的震荡环带及Pr_(N)-La_(N)和La_(N)-(Sm/La)_(N)等图解判断锆石为岩浆锆石。结合宝山嶂花岗斑岩Lu-Hf同位素特征,判断宝山嶂花岗斑岩为壳源岩石重熔的产物,岩浆物质主要源于下地壳的改造及再循环。The Baoshanzhang area in eastern Guangdong is located at the southwest end of the volcanic-intrusive rock zone along the southeast coast of the south China continent.In this paper,the zircon LA-ICP-MS U-Pb age,trace elements and Lu-Hf isotopes of the granite porphyry exposed in this area are studied to reveal the formation age,and to explore the genesis of zircon and magma source area.Zircon U-Pb dating shows that the weighted average age of the Baoshanzhang granite porphyry is 108.71±0.83Ma(MSWD=3.5,n=22),which belongs to the Late Early Cretaceous magmatic product.Through the Th/U contents of zircon,obvious oscillatory circle belts,as well as the Pr_(N)-La_(N) and La_(N)-(Sm/La)_(N) plots,show that zircon is magmatic zircon.Combined with the Lu-Hf isotope characteristics of the Baoshanzhang granite porphyry,it is judged that the Baoshanzhang granite porphyry is the product of remelting of crustal rocks,and the magmatic material mainly comes from the transformation and reworking of the lower crust.

关 键 词：早白垩世 锆石U-PB定年 微量元素 LU-HF同位素 

分 类 号：P597[天文地球—地球化学]