岩石矿物学杂志2025，Vol.44Issue(5)：1071-1091,21.DOI:10.20086/j.cnki.yskw.2025.4149
粤北隘子黑云母花岗岩年代学、岩石矿物地球化学及成因
Geochronology,geochemistry and petrogenesis of biotitle granite from the Aizi,northern Guangdong Province
摘要
Abstract
The Aizi pluton in the north of Guangdong is located in the central-western part of the Guidong complex pluton and consists of biotite granite.Currently,research on the formation age and genesis of this rock mass is weak,which is helpful to perfect the magmatic activity pedigree in the eastern Guizhou area,and provide new con-straints on the petrogenesis and tectonic background.In this paper,LA-ICP-MS zircon U-Pb chronology,mineral-petrogeochemistry and Hf-Nd isotopes have been studied for Aizi biotite granite.The mineralogical characteristics indicate that the zircons in the Aizhi biotite granite are magmatic zircons,and the apatites are fluorapatites.The zir-con U-Pb dating results indicate that the emplacement age of the Aizhi biotite granite is 159±1 Ma,which is a product of the early Yanshanian in South China.The geochemical characteristics of the rocks reveal a SiO2 content ranging from 67.93％to 69.80％,a high total alkali content(K2O+Na2O=7.32％to 7.53％)and A/CNK ratio of 0.95 to 0.99.The rocks are enriched in Rb,Th,and U,while depleted in elements such as Ba,Nb,Ta,Sr,Zr,and Hf.The LREE/HREE ratio varies between 7.24 and 10.17,with a pronounced negative Eu anomaly(δEu=0.43 to 0.50).The εHf(t)values of the Aizizi biotite granite range from-8.7 to-5.4,while the εNd(t)values range from-9.3 to-9.1,corresponding to tDM2 values of 1 725～1 519 Ma and 1 711～1 689 Ma,respectively.The above geochemical and isotopic characteristics indicate that the Aizhi biotite granite belongs to the high-potassi-um calc-alkaline series,quasi-aluminous S-I transitional granite,which is mainly formed by partial melting of Pa-leo-mesoproterozoic crustal-derived arenite under medium to high temperature and low pressure.Comprehensive studies suggest that the Aizhi biotite granite formed in a tectonic setting of lithospheric extension and thinning caused by the subduction of the Pacific plate.关键词
隘子岩体/花岗岩成因/锆石U-Pb年代学/地球化学/Hf-Nd同位素Key words
Aizi pluton/granite genesis/zircon U-Pb chronology/geochemistry/Hf-Nd isotope分类
天文与地球科学引用本文复制引用
王海洋,潘家永,刘光华,吴静仪,黄淑婷,王文意,陈子涵..粤北隘子黑云母花岗岩年代学、岩石矿物地球化学及成因[J].岩石矿物学杂志,2025,44(5):1071-1091,21.基金项目
东华理工大学-中国铀业有限公司联合创新基金(NRE2021-05,NRE2021-09) （NRE2021-05,NRE2021-09）
江西省研究生创新基金(YC2022-s957) （YC2022-s957）
江西省研究项目(NCSTI-RMF20230218) Joint Innovation Fund of East China University of Technology and China Uranium Industry Co.,Ltd.(NRE2021-05,NRE2021-09) （NCSTI-RMF20230218）
Jiangxi Province Graduate Innovation Fund(YC2022-s957) （YC2022-s957）
Jiangxi Provin-cial Research Project(NCSTI-RMF20230218) （NCSTI-RMF20230218）
